阅读说明：本技术 用于驱动电动车辆的设备 (Apparatus for driving electric vehicle ) 是由 成昌佑 安永赞 李正九 朴龙植 于 2020-04-28 设计创作，主要内容包括：本公开涉及用于驱动电动车辆的设备。该用于驱动电动车辆的设备包括驱动马达、马达轴、第一马达齿轮、第二马达齿轮、第一驱动齿轮、第二驱动齿轮、驱动轴、第一离合器和第二离合器。所述第二离合器是选择性单向离合器,所述选择性单向离合器基于致动器的操作用作轴承或者用作被配置为基于相对速度来约束所述第二驱动齿轮和所述驱动轴的单向离合器。(The present disclosure relates to an apparatus for driving an electric vehicle. The apparatus for driving an electric vehicle includes a drive motor, a motor shaft, a first motor gear, a second motor gear, a first drive gear, a second drive gear, a drive shaft, a first clutch, and a second clutch. The second clutch is a selective one-way clutch that functions as a bearing based on operation of an actuator or as a one-way clutch configured to constrain the second drive gear and the drive shaft based on relative speed.)

1. An apparatus for driving an electric vehicle, the apparatus comprising:

a drive motor and a motor shaft connected to the drive motor;

a first motor gear and a second motor gear coupled to an outer side of the motor shaft, spaced apart from each other;

a first drive gear and a second drive gear spaced apart from and engaged with the first motor gear and the second motor gear, respectively;

a drive shaft disposed outside the first drive gear and the second drive gear and connected to an axle;

a first clutch configured to connect the first drive gear to the drive shaft; and

a second clutch configured to connect the second drive gear to the drive shaft,

wherein the second clutch is a selective one-way clutch that functions as a bearing based on operation of an actuator or as a one-way clutch configured to constrain the second drive gear and the drive shaft based on relative speed.

2. The apparatus of claim 1, the apparatus further comprising:

a controller configured to operate the actuator to cause the second clutch to function as the one-way clutch when a first driving mode in which power is transmitted from the first driving gear to the driving shaft is switched to a second driving mode in which power is transmitted from the second driving gear to the driving shaft.

3. The apparatus of claim 2, wherein the controller controls the drive motor to operate at a first speed W1 in the first drive mode and a third speed W3 in the second drive mode; and is

Wherein, when the first driving mode is switched to the second driving mode, the controller controls the driving motor to operate at a second speed W2 lower than the first and third speeds, W2< W1 and W2< W3.

4. The apparatus of claim 1, wherein the first clutch is a one-way clutch configured to constrain the first drive gear and the drive shaft based on relative speed.

5. The apparatus of claim 1, wherein the first clutch is a selective one-way clutch that functions as a bearing or as a one-way clutch configured to constrain the first drive gear and the drive shaft based on relative speed,

wherein the drive shaft rotates at a different speed than the first drive gear and the second drive gear when the first clutch and the second clutch function as the bearing.

6. An apparatus for driving an electric vehicle, the apparatus comprising:

a drive motor and a motor shaft connected to the drive motor;

a first motor gear and a second motor gear coupled to an outer side of the motor shaft, spaced apart from each other;

a first drive gear and a second drive gear spaced apart from and engaged with the first motor gear and the second motor gear, respectively;

a drive shaft disposed outside the first and second drive gears and having a hollow portion formed therein;

a propeller shaft spline-coupled to the drive shaft and integrally rotated with the drive shaft; and

an actuator configured to move the drive shaft in an axial direction relative to the drive shaft,

wherein when the actuator moves the transmission shaft in an axial direction, the transmission shaft is coupled to any one of the first drive gear and the second drive gear and transmits power to the drive shaft.

7. The apparatus of claim 6, wherein the drive shaft comprises:

a drive shaft main body disposed inside the drive shaft; and

first and second drive shaft connectors extending from the drive shaft main body in an outward direction of a radial direction and provided on opposite sides of the drive shaft in an axial direction.

8. The apparatus of claim 7, wherein when the actuator moves the drive shaft in an axial direction, the first drive shaft connector is coupled to the first drive gear or the second drive shaft connector is coupled to the second drive gear, and the drive shaft transmits power to the drive shaft.

9. The apparatus of claim 7, wherein the drive shaft further comprises a drive shaft extension extending from the drive shaft body in an axial direction to connect to the actuator.

10. The apparatus according to claim 7, wherein the propeller shaft is formed by sequentially arranging the second propeller shaft connector, the propeller shaft main body, and the first propeller shaft connector from one side in an axial direction; and is

Wherein the drive shaft, the first drive gear and the second drive gear are disposed in an axial direction between the second driveshaft connector and the first driveshaft connector.

Technical Field

The present disclosure relates to an apparatus for driving an electric vehicle and a control method thereof.

Background

Recently, electric vehicles using electric power as a power source have been actively developed to replace vehicles using petroleum, which causes pollution. Hybrid vehicles using both oil and electricity as power sources are also being developed. In this case, the hybrid vehicle is classified as one type of electric vehicle. Accordingly, the hybrid vehicle is understood to be incorporated into an electric vehicle.

The electric vehicle includes a battery for supplying electric power and a drive device operated by the battery to rotate an axle. The drive device includes a drive motor for generating power by electric power supplied from a battery, and a transmission (or a gear box) for connecting the drive motor and the axle to each other.

A transmission is understood to be a device for decelerating or changing speed. In detail, the power generated by the driving motor is transmitted to the transmission, and the power transmitted from the transmission is decelerated or shifted and transmitted to the axle.

With regard to the transmission, the references cited below have been disclosed and registered.

1. Registration number 10-1532834 (published in 2015, 1 month and 12 days)

2. The invention name is as follows: two-step reduction drive apparatus for hybrid and electric vehicles

The cited reference discloses a two-speed reduction drive apparatus for hybrid and electric vehicles, which includes an input shaft connected to a drive motor, a counter shaft, and an output shaft, and includes a first gear and a second gear mounted on the output shaft.

In particular, the output shaft provides a shift sleeve (or synchronizer) that is selectively coupled to the first or second gear, and thus, the shift sleeve slides according to a shift command to shift the gear to first or second gear.

In this case, the gear reduction drive apparatus has the following problems.

First, the conventional gear reduction driving apparatus for an electric vehicle does not include a clutch for blocking power between a motor and a transmission during gear shifting, and thus has a problem in that when a previously closed gear is disengaged for gear shifting, a shock is generated due to an input torque of the motor.

Second, in order to overcome this problem, a friction clutch for blocking power between the motor and the transmission is additionally included in the apparatus, but there are problems in that controlling the friction clutch is complicated and the overall volume is increased, and the manufacturing cost is increased due to the addition of a clutch part.

Third, the conventional synchronizer for shifting includes a plurality of components such as a hub, a sleeve, a ring, a yoke, a cone, and a friction member, and thus there are problems in that the structure of the synchronizer is complicated and it is difficult to assemble the components. Therefore, there is a problem in that the assembly of the parts is not correct, resulting in product defects.

Disclosure of Invention

It is an object of the present disclosure to provide an electric vehicle driving apparatus for shifting gears using a selective one-way clutch.

Another object of the present disclosure is to provide an electric vehicle driving apparatus that separates a drive shaft and a propeller shaft to reduce the force required for gear shifting.

Another object of the present disclosure is to provide an electric vehicle driving apparatus that controls a speed of a driving motor during a shifting process and reduces a shock generated during the shifting process to shift using a speed synchronization process.

Another object of the present disclosure is to provide an electric vehicle driving apparatus having simplified components and a simple structure.

An electric vehicle drive apparatus according to the concepts of the present disclosure may apply a selective one-way clutch to the second gear. The selective one-way clutch may be used as a one-way clutch or a bearing.

The electric vehicle drive apparatus may include a drive shaft spline-coupled to a drive shaft configured as a hollow shaft to rotate integrally with each other while being to be relatively moved in an axial direction by an actuator.

According to one embodiment (first embodiment) shown in fig. 1 to 10, a one-way clutch may be applied to the first gear, and according to another embodiment (second embodiment) shown in fig. 11, a selective one-way clutch may also be applied to the first gear.

An electric vehicle driving apparatus according to an idea of the present disclosure may include: a drive motor and a motor shaft connected to the drive motor; a first motor gear and a second motor gear coupled to an outer side of the motor shaft, spaced apart from each other; a first drive gear and a second drive gear spaced apart from and engaged with the first motor gear and the second motor gear, respectively; and a drive shaft that is disposed outside the first drive gear and the second drive gear and is connected to an axle.

The electric vehicle driving apparatus may include: a first clutch configured to connect the first drive gear to the drive shaft; and a second clutch configured to connect the second drive gear to the drive shaft.

In this case, the second clutch may be a selective one-way clutch that functions as a bearing based on the operation of an actuator or as a one-way clutch configured to restrain the second drive gear and the drive shaft based on a relative speed.

The first clutch may be configured as a one-way clutch or a selective one-way clutch.

Another embodiment of an electric vehicle driving apparatus according to the idea of the present disclosure may include: a drive motor and a motor shaft connected to the drive motor; a first motor gear and a second motor gear coupled to an outer side of the motor shaft, spaced apart from each other; a first drive gear and a second drive gear spaced apart from and engaged with the first motor gear and the second motor gear, respectively; a drive shaft disposed outside the first and second drive gears and having a hollow portion formed therein; a transmission shaft spline-coupled to the drive shaft to rotate integrally with each other while being relatively moved in an axial direction by an actuator; and an actuator configured to move the drive shaft in an axial direction relative to the drive shaft.

When the actuator moves the transmission shaft in the axial direction, the transmission shaft may be coupled to any one of the first drive gear and the second drive gear and may transmit power to the drive shaft.

In this case, the electric vehicle driving apparatus may further include a first drive bearing and a second drive bearing provided between the first drive gear and the drive shaft and between the second drive gear and the drive shaft, respectively, to rotate the first drive gear and the second drive gear separately from the drive shaft.

That is, the first and second driving gears and the driving shaft may not directly transmit power, and may indirectly transmit power through a transmission shaft.

Drawings

Fig. 1 is a schematic view showing an electric vehicle driving apparatus according to an embodiment of the present disclosure.

Fig. 2 is a diagram illustrating a first driving mode of an electric vehicle driving apparatus according to one embodiment of the present disclosure.

Fig. 3 is a diagram illustrating a second driving mode of the electric vehicle driving apparatus according to one embodiment of the present disclosure.

Fig. 4 is a diagram showing a control configuration for switching the drive mode of the electric vehicle drive apparatus according to one embodiment of the present disclosure.

Fig. 5 is a control flowchart of the electric vehicle driving apparatus according to one embodiment of the present disclosure switching from the first driving mode to the second driving mode.

Fig. 6 and 7 are diagrams illustrating the second clutch in the first driving mode of the electric vehicle driving apparatus according to one embodiment of the present disclosure.

Fig. 8 to 10 are diagrams illustrating a second clutch in a second driving mode of an electric vehicle driving apparatus according to an embodiment of the present disclosure.

Fig. 11 is a schematic diagram of an electric vehicle driving apparatus according to another embodiment of the present disclosure.

Fig. 12 is a schematic diagram of an electric vehicle driving apparatus according to another embodiment of the present disclosure.

Fig. 13 is a diagram showing a configuration of an electric vehicle driving apparatus according to another embodiment of the present disclosure.

Fig. 14 is a diagram showing a first state of an electric vehicle driving apparatus according to another embodiment of the present disclosure.

Fig. 15 is a diagram illustrating a second state of an electric vehicle driving apparatus according to another embodiment of the present disclosure.

Fig. 16 is a diagram showing a part of a propeller shaft of an electric vehicle driving apparatus according to another embodiment of the present disclosure.

Fig. 17 is a diagram illustrating one side surface of a drive gear of an electric vehicle drive apparatus according to another embodiment of the present disclosure.

Fig. 18 is a diagram illustrating a coupling between a propeller shaft and a drive gear of an electric vehicle drive apparatus according to another embodiment of the present disclosure.

Detailed Description

Hereinafter, some embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. It should be noted that when parts in the drawings are designated by reference numerals, the same parts have the same reference numerals as much as possible even if the parts are illustrated in different drawings. In addition, in describing the embodiments of the present disclosure, when it is determined that detailed description of well-known configurations or functions interferes with understanding of the embodiments of the present disclosure, the detailed description will be omitted.

In addition, in describing embodiments of the present disclosure, terms such as first, second, A, B, (a) and (b) may be used. Each of these terms is used only to distinguish the corresponding component from other components and does not define the nature, order, or sequence of the corresponding components. It will be understood that when an element is "connected," "coupled," or "engaged" to another element, it can be directly connected or engaged to the other element or it can be "connected," "coupled," or "engaged" to the other element with a third element disposed between the element and the other element.

Fig. 1 is a schematic view showing an electric vehicle driving apparatus according to an embodiment of the present disclosure.

As shown in fig. 1, the electric vehicle driving apparatus according to the concept of the present disclosure may include a driving motor 10 and a transmission (or a gear box) for connecting the driving motor 10 to the axle 5.

The drive motor 10 may be understood as a device for generating power by supplying electric power from a battery. The axle 5 may be understood as a part directly connected to a wheel or the like. Fig. 1 illustrates axle 5 as one gear connected to the transmission and as a shaft extending on opposite sides of the gear. This is exemplary, and the axle 5 may be configured in various ways.

The transmission may include various gears and shafts. In detail, the power generated by the driving motor 10 may be transmitted to the transmission, and the power transmitted from the transmission may be decelerated or shifted and may be transmitted to the axle 5. Therefore, the transmission may be configured in various ways so as to connect the drive motor 10 and the axle 5 to each other. Hereinafter, the configuration of the transmission according to the idea of the present disclosure will be described in detail.

The electric vehicle driving apparatus according to the concept of the present disclosure may include a motor shaft 20 connected to the driving motor 10 and a driving shaft 30 connected to the axle 5. As shown in fig. 1, the motor shaft 20 and the drive shaft 30 may be spaced apart from each other and may each extend in an axial direction.

In this case, the motor shaft 20 and the drive motor 10 may be directly connected to each other, and the drive shaft 30 and the axle 5 may be indirectly connected to each other through a gear. For example, the drive shaft 30 may include a shaft connecting gear 32, and the axle 5 may include a drive shaft connecting gear 7 engaged with the shaft connecting gear 32.

The axle connecting gear 32 and the drive shaft connecting gear 7 may be installed at the drive shaft 30 and the axle 5, respectively, to rotate integrally with the drive shaft 30 and the axle 5, respectively. The rotational power of the drive shaft 30 can be transmitted to the axle 5 through the axle connecting gear 32 and the drive shaft connecting gear 7.

The connection between the motor shaft 20 and the drive motor 10 and the connection between the drive shaft 30 and the axle 5 are exemplary, and the present disclosure is not limited thereto. That is, the motor shaft 20 and the drive motor 10, and the drive shaft 30 and the axle 5 may have various coupling configurations for transmitting power.

An electric vehicle driving apparatus according to the concept of the present disclosure may include first and second motor gears 22 and 24, and first and second driving gears 42 and 44 engaged with the first and second motor gears 22 and 24, respectively.

In this case, the first motor gear 22 and the first driving gear 42 may be referred to as a first gear, and the second motor gear 24 and the second driving gear 44 may be referred to as a second gear. That is, the first motor gear 22 and the first drive gear 42 and the second motor gear 24 and the second drive gear 44 may engage with each other at different gear ratios. In this case, the gear ratio between the first gear and the second gear may be changed according to design.

The first and second motor gears 22 and 24 may be coupled to the outside of the motor shaft 20, spaced apart from each other. Accordingly, the motor shaft 20, the first motor gear 22, and the second motor gear 24 may be rotated integrally with each other by the driving motor 10.

That is, the motor shaft 20, the first motor gear 22, and the second motor gear 24 may have the same speed. In this case, the speed may be understood as an angular speed w corresponding to an angle corresponding to a rotation angle per unit time. Any speed described hereinafter refers to angular velocity.

In summary, when the drive motor 10 is operated at the predetermined speed w, the motor shaft 20, the first motor gear 22 and the second motor gear 24 may be understood to be rotated at the predetermined speed w.

The first and second drive gears 42, 44 may be disposed outside of the drive shaft 30, spaced apart from each other. In this case, the drive shaft 30, the first drive gear 42, and the second drive gear 44 may rotate at different speeds. To this end, the electric vehicle driving apparatus according to the concept of the present disclosure may include the first clutch 50 and the second clutch 40.

In particular, the drive shaft 30 may be rotated integrally with the first and second drive gears 42, 44 by the first and second clutches 50, 40. In this case, the case where the drive shaft 30 rotates integrally with the first drive gear 42 may be referred to as a first drive mode or a first-stage drive mode. In addition, the case where the drive shaft 30 rotates integrally with the second drive gear 44 may be referred to as a second drive mode or a second stage drive mode.

Hereinafter, the first driving mode and the second driving mode will be described in detail.

Fig. 2 is a diagram illustrating a first driving mode of an electric vehicle driving apparatus according to one embodiment of the present disclosure. Fig. 3 is a diagram illustrating a second driving mode of the electric vehicle driving apparatus according to one embodiment of the present disclosure. For ease of understanding, the transmission path of power is indicated by oblique lines in fig. 2 and 3.

As shown in fig. 2 and 3, in the first driving mode, power may be transmitted through the first gear, and in the second driving mode, power may be transmitted through the second gear. In detail, in the first driving mode shown in fig. 2, the driving shaft 30 may be integrally rotated with the first driving gear 42, and in the second driving mode shown in fig. 3, the driving shaft 30 may be integrally rotated with the second driving gear 44.

The first clutch 50 may perform a function of transmitting power of the first driving gear 42 to the driving shaft 30 in the first driving mode. The second clutch 40 may perform a function of transmitting power of the second driving gear 44 in the second driving mode.

In this case, the first clutch 50 of the electric vehicle driving apparatus according to the concept of the present disclosure may be configured as a one-way clutch, and the second clutch 40 may be configured as a selective one-way clutch. The one-way clutch may be a one-way clutch, and may refer to a connection member configured to transmit power in one direction.

The one-way clutch may be configured in various shapes and perform various functions. One-way clutches according to the present disclosure may be configured to connect one shaft and a gear. In addition, the gear and the shaft may be constrained to each other when the speed of the gear is higher than the speed of the shaft, and the gear and the shaft may not be constrained to each other when the speed of the shaft is higher than the speed of the gear. In this case, the constraint means to transmit power, that is, the shaft and the gear rotate integrally with each other.

A selective one-way clutch may refer to a connecting member that is selected to act as or not to act as a one-way clutch. That is, when the selective one-way clutch is used as a one-way clutch, the selective one-way clutch can transmit power according to the speeds of the shaft and the gear. Conversely, when the selective one-way clutch is not acting as a one-way clutch, the selective one-way clutch may transmit power regardless of the speed of the tube shaft and the gears.

The first clutch 50 may be a one-way clutch, and may be configured to transmit power in one direction. That is, in the first driving mode and the second driving mode, the first clutch 50 may be configured to transmit power in one direction.

In detail, the first clutch 50 may be configured to transmit power from the first driving gear 42 to the driving shaft 30 in the first driving mode. That is, in the first driving mode, the speed of the first driving gear 42 is higher than the speed of the driving shaft 30, and therefore, the first driving gear 42 and the driving shaft 30 may be constrained to each other and may rotate integrally with each other.

The first clutch 50 may be configured not to transmit power from the first drive gear 42 to the drive shaft 30 in the second drive mode. That is, in the second driving mode, when the speed of the first driving gear 42 is lower than the speed of the driving shaft 30, the first driving gear 42 and the driving shaft 30 may not be restricted from each other and may rotate at different speeds. In this case, the first driving gear 42 may be understood as being idle, not transmitting power.

The second clutch 40 may transmit power in one direction as the first clutch 50, or may be configured not to transmit power. In the first driving mode, the second clutch 40 may be configured not to transmit power, and in the second driving mode, the second clutch 40 may be configured to transmit power in one direction.

In this case, when the second clutch 40 is configured not to transmit power, the second clutch 40 may be understood to function as a bearing. In other words, when the second clutch 40 is not used as a one-way clutch, the second clutch 40 may be used as a bearing. To distinguish between the two, fig. 2 and 3 show a differently shaped second clutch 40. This is illustrated for ease of understanding, and the present disclosure is not limited thereto.

In detail, the second clutch 40 may be configured not to transmit power from the second driving gear 44 to the driving shaft 30 in the first driving mode. In this case, the second clutch 40 may correspond to a state in which the second clutch 40 is not used as a one-way clutch, i.e., a state in which the second clutch 40 is used as a bearing.

That is, in the first drive mode, second drive gear 44 and drive shaft 30 may rotate at different speeds, regardless of how the speeds of second drive gear 44 and drive shaft 30 are constrained to one another. In this case, the second driving gear 44 may be understood as being idle, not transmitting power.

Second clutch 40 may be configured to transmit power from second drive gear 44 to drive shaft 30 in the second drive mode. In this case, the second clutch 40 may be used as a one-way clutch. That is, in the second driving mode, the speed of the second driving gear 44 may be higher than the speed of the driving shaft 30, and thus, the second driving gear 44 and the driving shaft 30 may be constrained to each other and may rotate integrally with each other.

Based on this configuration, the drive shaft 30 may receive power using the first drive gear 42 or the second drive gear 44. That is, the electric vehicle driving apparatus may be driven, i.e., shifted at different speeds. Hereinafter, the shift corresponding to switching between the first drive mode and the second drive mode will be described in detail.

Fig. 4 is a diagram showing a control configuration for switching the drive mode of the electric vehicle drive apparatus according to one embodiment of the present disclosure.

As shown in fig. 4, the electric vehicle driving apparatus according to the concept of the present disclosure may include a controller 100. The controller 100 may be included in an electric vehicle in which the electric vehicle driving apparatus is installed, or may be installed outside the electric vehicle. For the electric vehicle driving apparatus, the controller 100 may be configured separately.

The controller 100 may control the driving motor 10. In detail, the controller 100 may control ON/OFF of the driving motor 10. Therefore, the controller 100 can control ON/OFF of the electric vehicle driving apparatus when the driving motor 10 operates and stops operating.

The controller 100 may control the speed of the drive motor 10. For example, the controller 100 may change the drive motor 10 from any one of the first speed W1, the second speed W2, and the third speed W3 to another, and may operate the drive motor 10. In this case, the first speed W1, the second speed W2, and the third speed W3 may be understood as different speed values.

The electric vehicle driving apparatus according to the concept of the present disclosure may further include an actuator 400, and the actuator 400 is included in the second clutch 40. The actuator 400 may be understood to be a part of the second clutch 40. The actuator 400 may be understood as a member configured to enable the second clutch 40 to function as a one-way clutch or as a bearing.

The controller 100 may control the operation of the actuator 400. That is, the controller 100 may control the second clutch 40 to function as a one-way clutch or as a bearing. As such, the controller 100 may switch between the first driving mode and the second driving mode.

An electric vehicle driving apparatus according to the concept of the present disclosure may include a power supply 110, a switching unit 120, a first sensor 130, and a second sensor 140. The power supply 110, the switching unit 120, the first sensor 130, and the second sensor 140 may correspond to components for transmitting predetermined signals or information to the controller 100. These components are distinguished from each other for convenience of description, and may be configured in various ways.

The power supply 110 may be understood as a means for receiving an ON/OFF signal of the electric vehicle driving apparatus and transmitting the ON/OFF signal to the controller 100. For example, the power supply 110 may correspond to a starting apparatus of an electric vehicle in which the electric vehicle driving apparatus is installed.

The switching unit 120 may be understood as a means for receiving a switching signal (i.e., a changeover signal of the first driving mode and the second driving mode) and transmitting the switching signal to the controller 100. For example, the switch unit 120 may correspond to a transmission of an electric vehicle in which the electric vehicle driving apparatus is installed.

The first sensor 130 and the second sensor 140 may correspond to a speed sensor for measuring a speed. In detail, the first sensor 130 may correspond to a sensor for measuring the speed of the driving shaft 30, and the second sensor 140 may correspond to a sensor for measuring the speed of the second driving gear 44.

The first sensor 130 and the second sensor 140 may be configured in various forms and may measure the speed. This is a description of the conventional speed sensor, and thus a description thereof is omitted. The electric vehicle driving apparatus according to the present disclosure may include various sensors.

Hereinafter, the shifting process will be described in detail based on the above configuration.

Fig. 5 is a control flowchart showing the electric vehicle driving apparatus according to one embodiment of the present disclosure switching from the first driving mode to the second driving mode.

As shown in fig. 5, the drive motor 10 may be operated at the first speed W1 (S10), and may be operated in the first drive mode (S20). In other words, when the drive motor 10 operates in the first drive mode, the drive motor 10 may be understood to be operating at the first speed W1. In this case, the first speed W1 may be determined according to the torque and speed appropriate for the first gear.

Referring to fig. 2, in the first driving mode, power may be transmitted to the axle 5 through the driving motor 10, the first motor gear 22, the first driving gear 42, and the driving shaft 30. That is, the first drive gear 42 and the drive shaft 30 may be constrained to each other by the first clutch 50 and may rotate integrally with each other.

As described above, in the first driving mode, the second clutch 40 functions as a bearing, and thus, the drive shaft 30 can rotate independently of the second drive gear 44. This may be understood as a state in which the actuator 400 is not operated or an OFF state of the actuator 400.

When the switching signal is input through the switching unit 120 (S30), switching to the second driving mode is started in the first driving mode. First, the drive motor 10 may be changed from the first speed W1 to the second speed W2 lower than the first speed W1 (W2 < W1) and may be operated (S40). That is, the drive motor 10 can be decelerated and operated as compared to the first drive mode.

As the drive motor 10 decelerates, the first motor gear 22 and the first drive gear 42 may also decelerate. In this case, the drive shaft 30 may be maintained at the original speed due to inertia. That is, the speed of the first drive gear 42 may become lower than the speed of the drive shaft 30. Therefore, the first drive gear 42 and the drive shaft 30 may not be constrained to each other by the first clutch 50 and may rotate at different speeds.

In this case, as the drive motor 10 decelerates, the second motor gear 24 and the second drive gear 44 may also decelerate. The second drive gear 44 may be configured to have a higher speed than the first drive gear 42 (speed of second drive gear > speed of first drive gear).

For example, as shown in fig. 1-3, the first drive gear 42 may be configured as a larger gear than the first motor gear 22. The second drive gear 44 may be configured as a similar gear as the second motor gear 24. Therefore, even if the first motor gear 22 and the second motor gear 24 are driven at the same speed, the second drive gear 44 can rotate faster than the first drive gear 42.

However, this is exemplary, and the second drive gear 44 may be configured in various forms to have a higher speed than the first drive gear 42. In other words, the first drive gear 42 may have a higher reduction ratio than the second drive gear 44.

Accordingly, the speed of the drive shaft 30 in the first drive mode may be lower than the speed of the second drive gear 44. However, in the first driving mode, the second clutch 40 functions as a bearing, and thus, the second driving gear 44 and the driving shaft 30 may not be constrained to each other.

As the change signal is input and the speed of the drive motor 10 is gradually reduced, the speed of the second drive gear 44 may become lower than the drive shaft 30. In other words, the drive motor 10 may be decelerated compared to the speed of the drive shaft 30 to reduce the speed of the second drive gear 44. Therefore, the second speed W2 may be understood as the speed of the drive motor 10, in which the speed of the second drive gear 44 becomes lower than the speed of the drive shaft 30.

When the speed of the second drive gear 44 becomes lower than the speed of the drive shaft 30 (S50), the actuator 400 may be operated (S60). That is, the second clutch 40 may be used as a one-way clutch by the actuator 400.

The drive motor 10 may be changed from the second speed W2 to the third speed W3 higher than the second speed W2(W2 < W3) and may be operated (S70). That is, the drive motor 10 can be accelerated and can be operated.

As the drive motor 10 accelerates, the second motor gear 24 and the second drive gear 44 may also accelerate. Therefore, the second drive gear 44 rotates faster than the drive shaft 30, and the second drive gear 44 and the drive shaft 30 may be constrained to each other by the second clutch 40 and may rotate integrally with each other.

As described above, the first drive gear 42 may be designed to rotate more slowly than the second drive gear 44. Therefore, the first drive gear 42 and the drive shaft 30 may not be constrained to each other by the first clutch 50 and may rotate at different speeds.

As a result, the drive motor 10 may be operated at the third speed W3 (S70), and may be operated in the second drive mode (S80). In other words, when the drive motor 10 operates in the second drive mode, the drive motor 10 may be understood to be operated at the third speed W3. In this case, the third speed W3 may be determined according to the torque and speed suitable for the second gear.

Referring to fig. 3, in the second driving mode, power may be transmitted to the axle 5 through the driving motor 10, the second motor gear 24, the second driving gear 44, and the driving shaft 30. That is, the second drive gear 44 and the drive shaft 30 may be constrained to each other and may rotate integrally with each other.

Through this process, the first drive mode can be switched to the second drive mode. In this case, with respect to the rotation of the drive shaft 30, the drive shaft 30 may be continuously accelerated rather than decelerated during the process of switching from the first drive mode to the second drive mode. That is, the shift shock may not be transmitted to the drive shaft 30 and the axle 5.

In the second driving mode, switching to the first driving mode may be performed in reverse in the same manner as the first driving mode. That is, the shift shock may not be transmitted to the drive shaft 30 and may be continuously reduced.

Regarding the operation of the drive motor 10, the speed of the drive motor 10 may be continuously changed without removing the motor torque. In particular, when the speed of the drive motor 10 is appropriately controlled, the speed of the drive motor 10 can be changed as continuously as possible, that is, the shift shock can be reduced.

Hereinafter, the second clutch 40 corresponding to the selective one-way clutch will be described in detail. In this case, the first clutch 50 corresponding to the one-way clutch has a conventional configuration, and thus a detailed description thereof is omitted.

Fig. 6 and 7 are diagrams illustrating the second clutch in the first driving mode of the electric vehicle driving apparatus according to one embodiment of the present disclosure. Fig. 8 to 10 are diagrams illustrating a second clutch in a second driving mode of an electric vehicle driving apparatus according to an embodiment of the present disclosure. For ease of understanding, the second clutch 40 and the second drive gear 44 are illustrated together.

As shown in fig. 6 to 9, the second clutch 40 may include an actuator 400. In this case, the actuator 400 may be coupled to one side of the driving shaft 30. That is, the actuator 400 may be fixed to the drive shaft 30 and may rotate together.

For example, referring to fig. 1 to 3, the drive shaft 30 may extend in the axial direction and may have one end on which an axle connecting gear 32 connected with the axle 5 is mounted. In addition, the first and second drive gears 42, 44 may be coupled to the outside of the drive shaft 30, spaced apart from each other in the axial direction.

In this case, the first drive gear 42 may be disposed adjacent to the axle connecting gear 32 as compared to the second drive gear 44. Thus, the axle connecting gear 32, the first drive gear 42, and the second drive gear 44 may be sequentially disposed in the axial direction. Additionally, the actuator 400 may be coupled to the other end of the drive shaft 30 adjacent to the second drive gear 44.

The second clutch 40 may include an outer ring 440 and an inner ring 420 disposed radially inward of the second drive gear 44. In this case, the outer ring 440 may be configured in an annular shape, and may be fixed to the inner circumference of the second driving gear 44. That is, the outer ring 440 may rotate integrally with the second drive gear 44.

The inner ring 420 may be disposed inside the outer ring 440 in a radial direction. The inner ring 420 may be disposed outside the drive shaft 30 in the radial direction. The inner ring 420 may be configured to move in an axial direction under the action of the actuator 400.

The second clutch 40 may also include a ball bearing 430 disposed between the outer race 440 and the inner race 420. A plurality of ball bearings 430 may be disposed between the outer ring 440 and the inner ring 420 to be spaced apart from each other in a circumferential direction. Although six ball bearings 430 are illustrated in the drawings, this is merely exemplary.

The inner ring 420 may rotate at a different speed than the outer ring 440 via the ball bearings 430. In summary, the inner ring 420 is connected to the actuator 400 and thus can rotate integrally with the drive shaft 30. The outer ring 440 may rotate integrally with the second drive gear 44.

Accordingly, the drive shaft 30 and the second drive gear 44 may rotate at different speeds by the ball bearing 430. That is, this may correspond to a state in which the second clutch 40 functions as a bearing. As shown in fig. 6 and 7, in the first driving mode, the driving shaft 30 and the second driving gear 44 may be connected to each other to be freely rotated by the ball bearing 430.

With operation of the actuator 400, the inner race 420 may move and the second clutch 40 may act as a one-way clutch. As shown in fig. 8 and 9, inner ring 420 may be inserted into second drive gear 44, extending therethrough. Thus, ball bearings 430 may be provided as shown in fig. 10.

As shown in fig. 10, a ball bearing receiver 424 on which ball bearings 430 are received and a ball bearing protrusion 422 for partitioning the ball bearing receiver 424 may be formed on the inner ring 420. The inner ring 420 may include a ball bearing support 450 for elastically supporting the ball bearing 430.

The ball bearing protrusion 422 may be bent in one direction. Accordingly, one side and the other side of the ball bearing receiver 424 may be formed to have different angles. The ball bearing support 450 may be obliquely disposed and may support the ball bearing 430.

In this case, the outer ring 440 may be constrained by the inner ring 420 when the outer ring 440 rotates in the direction a, and the outer ring 440 may not be constrained by the inner ring 420 when the outer ring 440 rotates in the direction B. Directions a and B may refer to relative rotation as the sum of rotations.

For example, when the outer ring 440 and the inner ring 420 both rotate in direction a, if the speed of the outer ring 440 is higher than the speed of the inner ring 420, the outer ring 440 may be instructed to rotate in direction a. When the speed of the inner ring 420 is higher than the speed of the outer ring 440, the outer ring 440 may be instructed to rotate in direction B.

When the outer ring 440 rotates in direction a, the ball bearings 430 may be spaced apart from the ball bearing supports 450. Ball bearings 430 may be interposed between the outer ring 440 and the inner ring 420. Accordingly, as the outer ring 440 rotates, a rotational force may be transmitted to the inner ring 420 through the ball bearings 430.

When the outer ring 440 rotates in the direction B, the ball bearing 430 may be elastically supported by the ball bearing support 450. As the outer ring 440 rotates, the ball bearing 430 may rotate while moving in a direction in which the ball bearing support 450 is compressed. That is, the rotational force of the outer ring 440 may not be transmitted to the inner ring 420.

In summary, in the first drive mode, the second clutch 40 may be provided as shown in fig. 6 and 7 and may function as a bearing. In the second driving mode, the second clutch 40 may be provided as shown in fig. 8 to 10 and may function as a one-way clutch. Therefore, in the second driving mode, when the speed of the second driving gear 44 is higher than the speed of the driving shaft 30, the second driving gear 44 and the driving shaft 30 may be restricted from each other and may rotate integrally with each other.

Fig. 11 is a schematic diagram of an electric vehicle driving apparatus according to another embodiment of the present disclosure.

As shown in fig. 11, both the first clutch 50 and the second clutch 40 of the electric vehicle driving apparatus according to the concept of the present disclosure may be configured as a selective one-way clutch. That is, unlike the description of fig. 1 to 11, the first clutch 50 may also be configured as a selective one-way clutch instead of a one-way clutch. Hereinafter, only the differences from the above description will be described, and the entire description except for the contradiction is cited.

The first clutch 50, which functions as a selective one-way clutch, may function as a one-way clutch or a bearing. In this case, the first clutch 50 may function as a one-way clutch in the first driving mode. Therefore, when the speed of the first drive gear 42 is higher than the speed of the drive shaft 30, the first drive gear 42 and the drive shaft 30 may be constrained to each other and may rotate integrally with each other.

In the second drive mode, the first clutch 50 may act as a bearing or a one-way clutch. When the first clutch 50 functions as a bearing, the first clutch 50 and the drive shaft 30 may not be constrained to each other regardless of the speed.

When the first clutch 50 functions as a one-way clutch, the drive shaft 30 may not be restrained by the first drive gear 42. This is because the drive shaft 30 restrained by the second drive gear 44 rotates faster than the first drive gear 42.

In summary, in the first drive mode, the first clutch 50 may function as a one-way clutch and the second clutch 40 may function as a bearing. In the second drive mode, the first clutch 50 may act as a one-way clutch or bearing and the second clutch 40 may act as a one-way clutch.

In other words, the second drive mode may be performed when the first clutch 50 functions as a bearing and the second clutch 40 functions as a one-way clutch. The first drive mode may be performed when the first clutch 50 functions as a one-way clutch and the second clutch 40 functions as a bearing. The second drive mode may be performed when the first clutch 50 and the second clutch 40 function as one-way clutches.

Both the first clutch 50 and the second clutch 40 may be used as bearings. That is, this may correspond to a state in which the drive shaft 30 is not constrained by the first drive gear 42 and the second drive gear 44. This state may be understood as a third drive mode or a neutral state.

Fig. 12 is a schematic diagram of an electric vehicle driving apparatus according to another embodiment of the present disclosure.

In the electric vehicle driving apparatus according to another embodiment shown in fig. 12, the first motor gear 22 and the second motor gear 24 may be coupled to an outer side of the motor shaft 20 to be spaced apart from each other. The first and second drive gears 42, 44 may be coupled to the outside of the drive shaft 30, spaced apart from each other. In this case, the first motor gear 22 and the second motor gear 24 may be integrally rotated with the motor shaft 20. Instead, the first and second drive gears 42 and 44 may rotate integrally with the drive shaft 30.

In other words, the first and second motor gears 22 and 24 may be coupled to the outside of the motor shaft 20 and may be rotated according to the rotation of the motor shaft 20. Conversely, the first and second driving gears 42 and 44 may be coupled to the outside of the driving shaft 30 to rotate differently from each other.

Therefore, the power of the first and second drive gears 42 and 44 engaged and rotated with the first and second motor gears 22 and 24 may not be directly transmitted to the drive shaft 30. With this configuration, the drive shaft 30 of the electric vehicle drive apparatus according to the concept of the present disclosure may be coupled to any one of the first drive gear 42 and the second drive gear 44 to receive power therefrom. Hereinafter, this will be described in detail.

Fig. 13 is a diagram showing a configuration of an electric vehicle driving apparatus according to another embodiment of the present disclosure. In fig. 13, a portion including the axle 5 is omitted for convenience of description. The size of the gears, shafts, etc. are exemplary and the disclosure is not limited thereto.

As shown in fig. 13, an electric vehicle driving apparatus according to the concept of the present disclosure may include a propeller shaft 70 and an actuator 400. In this case, the drive shaft 30 may be configured as a hollow shaft having a hollow formed therein.

The drive shaft 70 may be splined to the drive shaft 30. In detail, the transmission shaft 70 may rotate integrally with the drive shaft 30, and may be coupled to the drive shaft 30 to move in an axial direction with respect to the drive shaft 30. In this case, the actuator 400 may correspond to a member for moving the transmission shaft 70 in the axial direction with respect to the drive shaft 30.

When the actuator 400 moves the transmission shaft 70 in the axial direction, the transmission shaft 70 may be coupled to any one of the first and second drive gears 42 and 44. Accordingly, power may be transmitted from either of the first drive gear 42 and the second drive gear 44 to the drive shaft 30.

The drive shaft 70 may include a drive shaft body 72 and first and second drive shaft connectors 74 and 76, respectively, extending from the drive shaft body 72. In detail, the transmission shaft body 72 may extend in an axial direction. The first driveshaft connector 74 and the second driveshaft connector 76 may extend from the driveshaft body 72 in an outward direction in the radial direction.

The drive shaft body 72 may be disposed inside the drive shaft 30. In particular, the drive shaft body 72 may correspond to a portion splined to the drive shaft 30. That is, the outer circumference of the propeller shaft main body 72 and the inner circumference of the drive shaft 30 may be spline-coupled to each other. The spline coupling may be formed in various manners, for example, the outer circumference of the transmission shaft main body 72 and the inner circumference of the driving shaft 30 may include an uneven structure press-fitted to each other.

The first transmission shaft connector 74 and the second transmission shaft connector 76 may be disposed on opposite sides in the axial direction of the drive shaft 30. That is, the drive shaft 30 may be understood as being disposed between the second driveshaft connector 76 and the first driveshaft connector 74 in the axial direction. The first drive gear 42 and the second drive gear 44, which are arranged outside the drive shaft 30 in the radial direction, can also be understood as being arranged between the second driveshaft connector 76 and the first driveshaft connector 74 in the axial direction.

The first drive shaft connector 74 and the second drive shaft connector 76 may be shaped like circular plates. In this case, the first and second driveshaft connectors 74 and 76 may be configured to have a larger diameter than the drive shaft 30. However, first driveshaft connector 74 and second driveshaft connector 76 may have a smaller diameter than first drive gear 42 and second drive gear 44.

Accordingly, as shown in fig. 13, the propeller shaft 70 formed by the propeller shaft body 72 and the propeller shaft connectors 74 and 76 may be configured to have a dumbbell shape or "H" shape. In summary, the propeller shaft 70 may be formed by sequentially arranging the second propeller shaft connector 76, the propeller shaft main body 72, and the first propeller shaft connector 74 from one side in the axial direction.

The first and second driveshaft connectors 74, 76 may be spaced apart from the driveshaft 30 in the axial direction. This is because, when the transmission shaft 70 is moved in the axial direction by the actuator 400, it is necessary to prevent interference with the driven shaft 30.

In this case, when the actuator 400 moves the transmission shaft 70 in the axial direction, the first transmission shaft connector 74 and the first driving gear 42 may be coupled to each other, or the second transmission shaft connector 76 and the second driving gear 44 may be coupled to each other. Accordingly, power may be transmitted from either of the first drive gear 42 and the second drive gear 44 to the drive shaft 30.

In particular, one of the first drive shaft connector 74 and the first drive gear 42 may be inserted into the other to be coupled therewith, or one of the second drive shaft connector 76 and the second drive gear 44 may be inserted into the other to be coupled therewith. The coupling between the first driveshaft connector 74 and the first drive gear 42 and between the second driveshaft connector 76 and the second drive gear 44 will be described in detail below.

The drive shaft 70 may also include a drive shaft extension 78 connected to the actuator 400. The drive shaft extension 78 may extend from the drive shaft body 72 in an axial direction. That is, the actuator 400 may be installed at one side in the axial direction of the transmission shaft 70, and may move the transmission shaft 70 in the axial direction.

The driveshaft extension 78 may be understood to extend in an outer axial direction from either of the first driveshaft connector 74 and the second driveshaft connector 76. For example, as shown in fig. 13, the drive shaft extension 78 may extend from the first drive shaft connector 74 in an outer axial direction.

In other words, the first driveshaft connector 74 can be formed between the driveshaft body 72 and the driveshaft extension 78. Accordingly, the propeller shaft 70 may be understood as sequentially arranging the second propeller shaft connector 76, the propeller shaft main body 72, the first propeller shaft connector 74, and the propeller shaft extension 78 in the axial direction.

The drive shaft 70 may further include drive bearings 73 and 75, the drive bearings 73 and 75 being disposed between the drive shaft 70 and the drive shaft 30 to move in the axial direction while being spline-coupled to the drive shaft 30. The drive bearings 73 and 75 may be understood to guide the movement of the drive shaft 70 in the axial direction.

The drive bearings may include a first drive bearing 73 and a second drive bearing 75 spaced apart from each other in the axial direction. In particular, the first and second transmission bearings 73 and 75 may be disposed at opposite sides in the axial direction based on the portions spline-coupled with the drive shaft 30 and the transmission shaft 70. Therefore, the driving bearings 73 and 75 can stably support the driving shaft 70.

As described above, the first and second drive gears 42, 44 may be configured to rotate separately from the drive shaft 30. Accordingly, drive bearings 34 and 36 may be disposed between first and second drive gears 42 and 44 and drive shaft 30.

The drive bearing may include a first drive bearing 34 and a second drive bearing 36 spaced apart from each other in the axial direction. In this case, the first drive bearing 73 and the second drive bearing 75 may be provided inside the first drive bearing 34 and the second drive bearing 36 in the radial direction, respectively.

In summary, the transmission shaft 70, the first transmission bearing 73, the drive shaft 30, the first drive bearing 34, and the first drive gear 42 may be sequentially disposed in an outward direction from the inner radial direction. The transmission shaft 70, the second transmission bearing 75, the drive shaft 30, the second drive bearing 36, and the second drive gear 44 may be sequentially disposed in an outward direction from the inner radial direction.

This structure is exemplary, and the present disclosure is not limited thereto. Hereinafter, the power transmission in the arrangement state based on the movement of the transmission shaft 70 will be described in detail.

Fig. 14 is a diagram showing a first state of an electric vehicle driving apparatus according to another embodiment of the present disclosure. Fig. 15 is a diagram illustrating a second state of an electric vehicle driving apparatus according to another embodiment of the present disclosure. In this case, fig. 13 corresponds to the neutral state or the stop state. In other words, in the state of fig. 13, power may not be transmitted to the axle 5.

The first state shown in fig. 14 may correspond to a state in which the actuator 400 moves the transmission shaft 70 to one side in the axial direction. In detail, this may correspond to a state in which the actuator 400 moves the transmission shaft 70 in a direction away from the actuator 400.

The first state may correspond to a state in which first drive gear 42 is coupled to first driveshaft connector 74. As described above, the first driving gear 42 may correspond to the first gear connected with the first motor gear 22. Thus, the first state may be understood as a first level state.

When the drive motor 10 operates in the first state, the motor shaft 20 may be rotated and the first motor gear 22 and the second motor gear 24 may be removed. In addition, the first drive gear 42 and the second drive gear 44, which are engaged with the first motor gear 22 and the second motor gear 24, respectively, may rotate.

In this case, the first and second drive gears 42 and 44 may be configured to have a different gear ratio than the first and second motor gears 22 and 24, and thus, the first and second drive gears 42 and 44 may rotate at a different speed than the first and second motor gears 22 and 24.

First drive shaft connector 74 coupled to first drive gear 42 may rotate and drive shaft 70 may rotate. The drive shaft 30 coupled to the propeller shaft 70 may rotate and may transmit power to the axle 5. In summary, power may be transmitted to the drive motor 10, the first motor gear 22, the first drive gear 42, the transmission shaft 70, and the drive shaft 30.

In this case, the power transmitted to the driving motor 10, the second motor gear 24, and the second driving gear 44 may not be transmitted to the driving shaft 30. That is, the second drive gear 44 may rotate at a different speed than the drive shaft 30 through the second drive bearing 36.

The second state shown in fig. 15 may correspond to a state in which the actuator 400 moves the transmission shaft 70 toward the other side of the axial direction. In detail, this may correspond to a state in which the actuator 400 moves the transmission shaft 70 in a direction to approach the actuator 400.

The second state may refer to a state in which the second drive gear 44 and the second transmission shaft connector 76 are coupled to each other. As described above, the second driving gear 44 may correspond to a second gear coupled with the second motor gear 24. Thus, the second state may be understood as a second level state.

When the drive motor 10 operates in the second state, the motor shaft 20 may be rotated and the first motor gear 22 and the second motor gear 24 may be removed. The first and second drive gears 42, 44 engaged with the first and second motor gears 22, 24 may rotate.

The second drive shaft connector 76 coupled to the second drive gear 44 may rotate and the drive shaft 70 may rotate. The drive shaft 30 coupled to the propeller shaft 70 may rotate and may transmit power to the axle 5. In summary, power may be transmitted to the drive motor 10, the second motor gear 24, the second drive gear 44, the transmission shaft 70, and the drive shaft 30.

In this case, the power transmitted to the driving motor 10, the first motor gear 22, and the first driving gear 42 may not be transmitted to the driving shaft 30. That is, the first drive gear 42 may rotate at a different speed than the drive shaft 30 through the first drive bearing 34.

As such, when the actuator 400 moves the transmission shaft 70 toward one side or the other side in the axial direction, power may be differently transmitted to the drive shaft 30. Hereinafter, the coupling between the drive gears 42 and 44 and the transmission shaft 70 will be described in detail.

Fig. 16 is a diagram showing a part of a propeller shaft of an electric vehicle driving apparatus according to another embodiment of the present disclosure. Fig. 17 is a diagram illustrating one side surface of a drive gear of an electric vehicle drive apparatus according to another embodiment of the present disclosure.

For convenience of description, fig. 16 shows a portion of the transmission shaft 70 in the axial direction, and fig. 17 shows one side surface of the first drive gear 42 or the second drive gear 44.

The coupling between first drive gear 42 and first drive shaft connector 74 and the coupling between second drive gear 44 and second drive shaft connector 76 may be accomplished in the same manner. That is, the transmission shaft 70 may have the same coupling form at opposite sides in the axial direction. Therefore, the coupling form of one side of the transmission shaft 70 is illustrated and described, and the description thereof can also be applied to the coupling form of the other side.

Hereinafter, the first drive gear 42 or the second drive gear 44 will be described as the drive gears 42 and 44, and the first propeller shaft connector 74 or the second propeller shaft connector 76 will be described as the propeller shaft connectors 74 and 76.

As shown in fig. 16, the propeller shaft connectors 74 and 76 may include a connection protrusion 500, and the connection protrusion 500 is formed to be inserted into the driving gears 42 and 44. In this case, the connection protrusion 500 may include a first connection protrusion formed on the first transmission shaft connector 74 to be inserted into the first drive gear 42 and a second connection protrusion formed on the second transmission shaft connector 76 to be inserted into the second drive gear 44.

The connection protrusion 500 may protrude from the propeller shaft connectors 74 and 76 toward the propeller shaft main body 72 in the axial direction. The connection protrusion 500 may be formed on one side surface of the propeller shaft connectors 74 and 76 adjacent to the propeller shaft main body 72 in the axial direction.

Although fig. 16 illustrates only one connection protrusion 500, a plurality of connection protrusions 500 may be formed. For example, the plurality of connection protrusions 500 may be formed to be spaced apart from each other in the circumferential direction based on the transmission shaft main body 72.

The propeller shaft connectors 74 and 76 may also include a connection ball bearing 502 protruding from the connection protrusion 500. In this case, the connection ball bearing 502 may include a first connection ball bearing protruding from the first connection protrusion and a second connection ball bearing protruding from the second connection protrusion.

In detail, the connection protrusion 500 may be formed in a hollow cylindrical shape and may extend in an axial direction. One extended end of the connection protrusion 500 may be open. At least a portion of the connection ball bearing 502 may be inserted into the connection protrusion 500. In this case, the inner space of the connection protrusion 500 may be configured to correspond to the size of the connection ball bearing 502.

Therefore, the connecting ball bearing 502 may be disposed on the outermost side in the axial direction of the propeller shaft connectors 74 and 76. In detail, the connecting ball bearings 502 may be disposed on the driveshaft connectors 74 and 76, closest to the drive gears 42 and 44. That is, the connection ball bearing 502 may be understood to protrude on the connection protrusion 500 to contact the driving gears 42 and 44.

As shown in fig. 17, the driving gears 42 and 44 may include a coupling groove 602 that is recessed to allow the coupling protrusion 500 to be inserted therein. The coupling groove 602 may include a first coupling groove recessed in the first driving gear 42 to allow the first coupling protrusion to be inserted therein and a second coupling groove recessed in the second driving gear 44 to allow the second coupling protrusion to be inserted therein.

The connecting groove 602 may extend in the circumferential direction on one side in the axial direction of the drive gears 42 and 44. That is, the coupling groove 602 may be understood as a curved groove recessed in an arc shape.

In this case, the coupling groove 602 may be received with a depth varying in the circumferential direction. In particular, the coupling groove 602 may be formed with a recess depth linearly varying in a circumferential direction.

In detail, the coupling groove 602 may include a first coupling groove end portion 606 and a second coupling groove end portion 608 corresponding to opposite ends in a circumferential direction. In this case, the second coupling groove end 608 may be recessed by a maximum depth to have a step difference with the ends of the driving gears 42 and 44. The first connecting slot end 606 may be smoothly connected to the ends of the driving gears 42 and 44.

That is, first connection slot end 606 may be formed with an increased receiving depth toward second connection slot end 608. In addition, the first coupling groove end 606 may have a linearly varying recess depth without forming a step toward the second coupling groove end 608.

The driving gears 42 and 44 may include a connection protrusion 600 having a connection groove 602 formed therein. Referring to the cross-sections of the drive gears 42 and 44 shown in fig. 13-15, the drive gears 42 and 44 may have an outer circumference in contact with the motor gears 22 and 24 and an inner circumference in contact with the drive bearings 34 and 36. The connection protrusion 600 may protrude between the inner circumference and the outer circumference in the axial direction.

In particular, the connection protrusions 600 may protrude from the drive gears 42 and 44 in an axial direction toward the driveshaft connectors 74 and 76. The connection protrusion 600 may be formed on one side surface of the driving gears 42 and 44 in the axial direction adjacent to the transmission shaft connectors 74 and 76.

The coupling process of the drive gears 42 and 44 and the propeller shaft connectors 74 and 76 using the above-described configuration will be described.

Fig. 18 is a diagram illustrating a coupling between a propeller shaft and a drive gear of an electric vehicle drive apparatus according to another embodiment of the present disclosure. For convenience of description, fig. 18 (a), fig. 18 (b), fig. 18 (c), and fig. 18 (d) show a process in which the drive shaft 70 is moved toward one side in the axial direction (the right side in fig. 18) by the actuators 400 divided according to the distance.

Fig. 18 (a) corresponds to a state in which the drive gears 42 and 44 and the propeller shaft connectors 74 and 76 are not coupled to each other. In this case, it can be assumed that the drive gears 42 and 44 are rotated by the operation of the drive motor 10. The drive gears 42 and 44 and the propeller shaft connectors 74 and 76 are not coupled to each other, and thus, power cannot be transmitted to the drive shaft 30.

When the actuator 400 moves the transmission shaft 70, the drive gears 42 and 44 and the transmission shaft connectors 74 and 76 may contact each other, as shown in (b) of fig. 18. In detail, the connection ball bearing 502 and the connection protrusion 600, which are formed to be closest to each other in the axial direction, may contact each other. Accordingly, the rotational force of the driving gears 42 and 44 may be transmitted to the connecting ball bearing 502, and the connecting ball bearing 502 may rotate.

In this case, the connection groove 602 and the connection ball bearing 502 may also be contacted according to the rotational positions of the drive gears 42 and 44. For convenience of description, fig. 18 shows a case in which the connection ball bearing 502 contacts the connection protrusion 600 in which the connection groove 602 is not formed.

The propeller shaft connectors 74 and 76 may further include connection elastic members 504, and the connection elastic members 504 are installed in the connection protrusions 500 to elastically support the connection ball bearings 502. The connection elastic member 504 may include a first connection elastic member mounted in the first connection protrusion to elastically support the first connection ball bearing and a second connection elastic member mounted in the second connection protrusion to elastically support the second connection ball bearing.

The connection elastic member 504 may be installed to extend or compress in the axial direction, and may elastically support the connection ball bearing 502 in the axial direction. Accordingly, the connection ball bearing 502 may contact the connection protrusion 600 and may be compressed by the connection elastic member 504, and the connection ball bearing 502 may be inserted into the connection protrusion 500.

As the actuator 400 continuously moves the transmission shaft 70, the connection protrusion 500 may be inserted into the connection groove 602, as shown in (c) of fig. 18. In particular, drive gears 42 and 44 may rotate to allow first connection slot end 606 to pre-contact connection tab 500 as compared to second connection slot end 608.

Accordingly, the coupling protrusion 500 may be inserted into the coupling groove 602 from the first coupling groove end 606 along the second coupling groove end 608. As a result, as shown in (d) of fig. 18, the connection protrusion 500 may be inserted into the second connection groove end 608, and the driving gears 42 and 44 and the transmission shaft connectors 74 and 76 may be coupled to each other.

When the actuator 400 moves the transmission shaft 70 toward the other side in the axial direction (the left side in fig. 18), the drive gears 42 and 44 and the transmission shaft connectors 74 and 76 can be separated from each other by the state of (d) in fig. 18, (c) in fig. 18, (b) in fig. 18, and (a) in fig. 18.

In this case, (a) in fig. 18 shows the disengaged state and (d) in fig. 18 shows the coupled state. Fig. 18 (b) and 18 (c) can be understood as based on the buffer state of disconnection or connection. That is, the driving gears 42 and 44 and the transmission shaft connectors 74 and 76 may be coupled and decoupled without a large impact by the shape of the connection ball bearing 502, the connection elastic member 504, and the connection groove 602.

As such, the electric vehicle driving apparatus according to the idea of the present disclosure can switch the first stage state and the second stage state without a large impact. For example, when the first stage state is switched to the second stage state, the state in which the first drive gear 42 and the first driveshaft connector 74 are coupled to each other may be switched to the state in which the second drive gear 44 and the second driveshaft connector 76 are coupled to each other.

In a state where the first drive gear 42 and the first transmission shaft connector 74 are coupled to each other as shown in fig. 14, the actuator 400 may move the transmission shaft 70 toward one side (the right side of fig. 14). Accordingly, the first coupling protrusion may be separated from the first coupling groove, and the first coupling ball bearing may be rotated by the first driving gear 42 to reduce the impact.

The first coupling groove may be completely separated from the first coupling protrusion, and the second coupling ball bearing and the second driving gear 44 may contact each other to reduce the impact. The second connection protrusion may be inserted into the second connection groove, and the second driving gear 44 and the second driving shaft connector 76 may be coupled to each other.

As such, the present disclosure may provide a configuration that reduces the force required for shifting by separating the drive shaft and the propeller shaft and reduces the speed synchronization time using a connecting ball bearing or the like. Therefore, with a relatively simple structure, the shift shock can be reduced and the speed can be changed.

The electric vehicle driving apparatus according to the embodiments of the present disclosure configured as above may have the following effects.

The speed change may be continuously performed by a clutch and a driving motor included in the driving gear, and thus, it may be advantageous that the change shock is not transmitted to the user through the driving shaft and the axle.

The one-way clutch may be configured without a complicated structure, and it may be advantageous that the speed change may be performed by a relatively simple structure according to the speed control of the driving motor.

In particular, when the selective one-way clutch is switched to the one-way clutch or the bearing by the actuator, it may be advantageous that the change time required for the gear shift can be significantly reduced and the operational reliability can be enhanced.

A component (synchronizer) required for shifting can be omitted from the conventional device, and therefore, it may be advantageous to simplify the configuration of the transmission and minimize shift shock generated during shifting.

It may be advantageous to perform the gear change relatively simply by a drive shaft configured as a hollow shaft and a transmission shaft splined to the drive shaft to rotate integrally with each other while being to be relatively moved in an axial direction by an actuator.

In particular, the transmission shaft may reciprocate straightly to be coupled to the driving gear and may shift gears, and thus, it may be advantageous to significantly reduce a shifting time required for shifting gears and enhance operational reliability.

Since the first drive gear (or the first gear) or the second drive gear (or the second gear) is smoothly coupled to the transmission shaft by speed synchronization, it may be advantageous to further reduce shift shock and noise.