阅读说明：本技术 具有锁定检测机构的电子致动的锁定差速器 (Electronically actuated locking differential with lock detection mechanism ) 是由 鲁佩什·马杜卡尔·苏尔夫 斯瓦普尼尔·希瓦吉·卡达姆 查德·罗伯特·希尔曼 于 2018-03-03 设计创作，主要内容包括：根据本公开构造的电子锁定差速器组件包括差速器壳体、第一侧齿轮和第二侧齿轮、锁定致动组件和锁定检测机构。第一齿轮限定第一轴开口,该第一轴开口被配置成提供与被接纳在第一输出轴开口内的第一输出轴的第一扭矩传递连接。第二侧齿轮限定第二输出轴开口,该第二输出轴开口被配置成提供与接纳在第二输出轴开口内的第二输出轴的第二扭矩传递连接。锁定致动机构在其中侧齿轮被固定以同时旋转的锁定状态和其中侧齿轮相对于彼此旋转的解锁状态之间选择性地移动。锁定检测机构检测锁定致动机构是处于锁定状态还是解锁状态。(An electronic locking differential assembly constructed in accordance with the present disclosure includes a differential housing, first and second side gears, a lock actuation assembly, and a lock detection mechanism. The first gear defines a first shaft opening configured to provide a first torque transmitting connection with a first output shaft received within the first output shaft opening. The second side gear defines a second output shaft opening configured to provide a second torque-transmitting connection with a second output shaft received within the second output shaft opening. The lock actuation mechanism is selectively movable between a locked state in which the side gears are fixed for simultaneous rotation and an unlocked state in which the side gears rotate relative to each other. The lock detection mechanism detects whether the lock actuation mechanism is in the locked state or the unlocked state.)

1. An electronic locking differential assembly comprising:

a differential housing defining a first output shaft opening and a second output shaft opening, the first and second output shaft openings being coaxially aligned along an axis of rotation of the differential housing;

A first side gear and a second side gear rotatably mounted within the differential housing, the first side gear and the second side gear coaxially aligned along the rotational axis of the differential housing, the first side gear defining a first shaft opening configured to provide a first torque transfer connection with a first output shaft received within the first output shaft opening, the second side gear defining a second output shaft opening configured to provide a second torque transfer connection with a second output shaft received within the second output shaft opening;

A lock actuation mechanism selectively movable between a locked state in which the side gears are fixed for simultaneous rotation and an unlocked state in which the side gears rotate relative to each other; and

A lock detection mechanism that detects whether the lock actuation mechanism is in the locked state or the unlocked state.

2. the electronic locking differential assembly of claim 1 wherein the lock actuation mechanism includes an armature and a stator assembly, the stator assembly having an electromagnetic coil.

3. The electronic locking differential assembly of claim 2 wherein the lock detection mechanism includes a first member fixed to move simultaneously with the armature and relative to a second member.

4. The electronic locking differential assembly of claim 3 wherein the first member is coupled to a carrier that is fixed to move with the armature.

5. The electronic locking differential assembly of claim 4 wherein the first member has a first terminal and the second member has a second terminal, wherein the first and second terminals move to predetermined positions relative to each other until a switch changes state and sends a signal to a controller indicating the locked state.

6. The electronic locking differential assembly of claim 5, wherein the armature is configured to translate along a first distance, whereby the switch remains in a first state, and subsequently translate along a second distance, whereby the switch remains in a second state.

7. the electronic locking differential of claim 6, wherein the switch is normally open.

8. the electronic locking differential of claim 6, wherein the switch is normally closed.

9. The electronic locking differential of claim 4, wherein the first member rotates as the carrier translates.

10. The electronic locking differential of claim 9, further comprising a biasing member that biases the first member toward an open position indicating an unlocked state.

11. The electronic locking differential of claim 10, wherein the first member includes pawls that rotate into contact with the second member.

12. the electronic locking differential of claim 11, wherein the pawl is fixed for rotation with a shaft that is caused to rotate upon rotation of a swing arm configured on the lock detection mechanism.

13. The electronic locking differential of claim 12, further comprising a post coupled to a carrier, the post engaging and forcing the swing arm to rotate as the carrier translates.

14. The differential gear assembly according to claim 1, wherein a pair of pinion gears intermesh with the first and second side gears to form a torque transmitting arrangement configured for transmitting torque between the pinion gears and the first and second side gears to rotate the first and second side gears about the axis of rotation, the torque transmitting arrangement further configured for allowing the first and second side gears to rotate about the axis of rotation at different rotational speeds relative to one another in the unlocked state.

15. the differential gear assembly according to claim 1, wherein said lock-up detection mechanism includes a normally open mechanical switch.

16. An electronic locking differential assembly comprising:

A differential housing defining a first output shaft opening and a second output shaft opening, the first and second output shaft openings being coaxially aligned along an axis of rotation of the differential housing;

A first side gear and a second side gear rotatably mounted within the differential housing, the first side gear and the second side gear coaxially aligned along the rotational axis of the differential housing, the first side gear defining a first shaft opening configured to provide a first torque transfer connection with a first output shaft received within the first output shaft opening, the second side gear defining a second output shaft opening configured to provide a second torque transfer connection with a second output shaft received within the second output shaft opening;

A lock actuation mechanism selectively movable between a locked state in which the side gears are fixed for simultaneous rotation and an unlocked state in which the side gears rotate relative to each other, the lock actuation mechanism having an armature configured to translate when an electromagnetic coil is energized; and

a lock detection mechanism that detects whether the lock actuation mechanism is in the locked state or the unlocked state, the lock detection mechanism further including:

a normally open switch that moves between an open position corresponding to the unlocked state and a closed position corresponding to the locked state, the normally open switch having a first member configured to move with the armature relative to a second member:

Along a first distance corresponding to the open position; and

Along a second distance corresponding to the closed position.

17. the electronic locking differential assembly as defined in claim 16, further comprising a first terminal disposed on the first member and a second terminal disposed on the second member, wherein the first and second terminals are a sufficient distance apart along the first distance whereby the normally open switch remains open.

18. The electronic locking differential assembly of claim 17 wherein the first member is coupled to a carrier that is fixed to move with the armature.

19. the electronic locking differential of claim 17, wherein the first member includes a pawl that rotates into contact with the second member, wherein the pawl is fixed to rotate with a shaft that is caused to rotate when a swing arm configured on the lock detection mechanism rotates, the lock detection mechanism further comprising a post coupled to a carrier that engages and forces the swing arm to rotate when the carrier translates.

20. An electronic locking differential assembly comprising:

A differential housing defining a first output shaft opening and a second output shaft opening, the first and second output shaft openings being coaxially aligned along an axis of rotation of the differential housing;

A first side gear and a second side gear rotatably mounted within the differential housing, the first side gear and the second side gear coaxially aligned along the rotational axis of the differential housing, the first side gear defining a first shaft opening configured to provide a first torque transfer connection with a first output shaft received within the first output shaft opening, the second side gear defining a second output shaft opening configured to provide a second torque transfer connection with a second output shaft received within the second output shaft opening;

a lock actuation mechanism selectively movable between a locked state in which the side gears are fixed for simultaneous rotation and an unlocked state in which the side gears rotate relative to each other, the lock actuation mechanism having an armature configured to translate when an electromagnetic coil is energized; and

A lock detection mechanism that detects whether the lock actuation mechanism is in the locked state or the unlocked state, the lock detection mechanism further including:

A normally closed switch that moves between a closed position corresponding to the unlocked state and an open position corresponding to the locked state, the normally closed switch having a first member configured to move with the armature relative to a second member:

Along a first distance corresponding to the closed position; and

Along a second distance corresponding to the open position.

Technical Field

the present disclosure relates generally to differential gear assemblies and, more particularly, to an electronically actuated locking differential having a lock detection mechanism.

Background

a differential gear mechanism can be disposed in the axle wheel assembly and used to transmit torque from the drive shaft to the pair of output shafts. The drive shaft can drive the differential through the use of bevel gears that mesh with a ring gear mounted to the housing of the differential. In automotive applications, differentials allow tires mounted at either end of an axle wheel assembly to rotate at different speeds. This is important when the vehicle is turning, as the tire casing travels over an arc of greater distance than the tire tube. Therefore, the tire casing must rotate at a faster speed than the tire tube to compensate for the greater travel distance. The differential includes a differential housing and a gear arrangement that allows torque to be transmitted from the drive shaft to the output shaft while allowing the output shaft to rotate at different speeds as desired. The gear arrangement can generally include a pair of side gears mounted for rotation with respective output shafts. A series of cross pins or pinion shafts are fixedly mounted to the differential case for rotation therewith. A corresponding plurality of pinion gears are mounted for rotation with the pinion shaft and are in meshing relationship with the two side gears.

some differential gear mechanisms include traction modifying differentials, such as those that provide a locking function. The locking differential includes some sort of locking mechanism to prevent rotation of one of the side gears relative to the gear housing, the engagement of the locking mechanism being initiated by some sort of actuator. By way of example only, the actuator can include a ball ramp mechanism in which rotation of the ramp plate is delayed relative to the gear housing, which initiates the ramp in response to a signal being transmitted to an electromagnetic coil disposed adjacent the ramp plate. Other configurations are direct acting and utilize a dog clutch that is moved into interlocking with the side gears by a push-in rod that is moved by the movement of the armature when the coil is energized. In this regard, a number of configurations are available. Examples of locking differentials of the type described above are shown in U.S. Pat. Nos. 6,083,134 and 6,551,209, both assigned to the assignee of the present disclosure and incorporated herein by reference. In such examples, transmitting the input signal to the electromagnetic coil causes the locking member to engage a mating portion associated with a differential side gear disposed adjacent the actuator arrangement. In some cases, the differential can remain locked after the solenoid is turned off, such as due to a torque trap between the dog teeth.

the background description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.

Disclosure of Invention

An electronic locking differential assembly constructed in accordance with the present disclosure includes a differential housing, first and second side gears, a lock actuation assembly, and a lock detection mechanism. The differential housing defines a first output shaft opening and a second output shaft opening, the first output shaft opening and the second output shaft opening being coaxially aligned along an axis of rotation of the differential housing. The first gear defines a first shaft opening configured to provide a first torque transmitting connection with a first output shaft received within the first output shaft opening. The second side gear defines a second output shaft opening configured to provide a second torque-transmitting connection with a second output shaft received within the second output shaft opening. The lock actuation mechanism is selectively movable between a locked state in which the side gears are fixed for simultaneous rotation and an unlocked state in which the side gears rotate relative to each other. The lock detection mechanism detects whether the lock actuation mechanism is in the locked state or the unlocked state.

According to an additional feature, the lock actuation mechanism includes an armature and a stator assembly. The stator assembly has an electromagnetic coil. The lock detection mechanism includes a first member fixed to move simultaneously with the armature and to move relative to a second member. The first member can be coupled to a carriage that is fixed to move with the armature. The first member has a first terminal and the second member has a second terminal. The first and second terminals move to predetermined positions relative to each other until the switch changes state and sends a signal to a controller indicating a locked state.

in other features, the armature is configured to translate along a first distance, whereby the switch remains in the first state, and subsequently translate along a second distance, whereby the switch remains in the second state. In one example, the switch is normally open. In another example, the switch is normally closed. The first member rotates as the carriage translates.

According to other features, the lock detection mechanism further includes a biasing member that biases the first member toward an open position indicating the unlocked state. The first member can include a pawl that rotates into contact with the second member. The pawl can be fixed to rotate with a shaft that is caused to rotate when a swing arm disposed on the lock detection mechanism rotates. The post can be coupled to the bracket. The post is able to engage and force the swing arm to rotate as the carriage translates. The pair of pinion gears are configured to intermesh with the first and second side gears to form a torque transfer arrangement configured to transfer torque between the pinion gears and the first and second side gears to rotate the first and second side gears about the axis of rotation. The torque transmitting arrangement is further configured for allowing the first and second side gears to rotate at different rotational speeds relative to each other about the rotational axis in the unlocked state. The lock detection mechanism includes a mechanical switch that is normally open.

An electronic locking differential assembly constructed in accordance with the present disclosure includes a differential housing, first and second side gears, a lock actuation assembly, and a lock detection mechanism. The differential housing defines a first output shaft opening and a second output shaft opening, the first output shaft opening and the second output shaft opening being coaxially aligned along an axis of rotation of the differential housing. The first gear defines a first shaft opening configured to provide a first torque transmitting connection with a first output shaft received within the first output shaft opening. The second side gear defines a second output shaft opening configured to provide a second torque-transmitting connection with a second output shaft received within the second output shaft opening. The lock actuation mechanism is selectively movable between a locked state in which the side gears are fixed for simultaneous rotation and an unlocked state in which the side gears rotate relative to each other. The lockout actuation mechanism has an armature configured to translate when the electromagnetic coil is energized. The lock detection mechanism detects whether the lock actuation mechanism is in the locked state or the unlocked state. The lock detection mechanism includes a normally open switch that moves between an open position corresponding to an unlocked state and a closed position corresponding to a locked state. The normally open switch has a first member configured to move with the armature relative to a second member along a first distance corresponding to an open position and along a second distance corresponding to a closed position.

According to other features, the first and second terminals disposed on the respective first and second members are spaced apart a sufficient distance along the first distance such that the normally open switch remains open. The first member can be coupled to a carriage that is fixed to move with the armature. The first member can include a pawl that rotates into contact with the second member, wherein the pawl is fixed to rotate with a shaft that is caused to rotate upon rotation of a swing arm configured on the lock detection mechanism. The lock detection mechanism also includes a post coupled to the carriage that engages and forces the swing arm to rotate as the carriage translates.

An electronic locking differential assembly constructed in accordance with the present disclosure includes a differential housing, first and second side gears, a lock actuation assembly, and a lock detection mechanism. The differential housing defines a first output shaft opening and a second output shaft opening, the first output shaft opening and the second output shaft opening being coaxially aligned along an axis of rotation of the differential housing. The first gear defines a first shaft opening configured to provide a first torque transmitting connection with a first output shaft received within the first output shaft opening. The second side gear defines a second output shaft opening configured to provide a second torque-transmitting connection with a second output shaft received within the second output shaft opening. The lock actuation mechanism is selectively movable between a locked state in which the side gears are fixed for simultaneous rotation and an unlocked state in which the side gears rotate relative to each other. The lockout actuation mechanism has an armature configured to translate when an electromagnetic coil is energized. The lock detection mechanism detects whether the lock actuation mechanism is in the locked state or the unlocked state. The lock detection mechanism includes a normally closed switch that moves between a closed position corresponding to the unlocked state and an open position corresponding to the locked state. The normally closed switch has a first member configured to move with the armature relative to a second member along a first distance corresponding to a closed position and along a second distance corresponding to an open position.

Drawings

the present disclosure will become more fully understood from the detailed description and the accompanying drawings, wherein:

FIG. 1 is a cross-sectional view of an electronic locking differential gear mechanism according to one example of the present disclosure;

FIG. 2 is a detailed cross-sectional view of the electronic locking differential gear mechanism of FIG. 1, showing a lock detection sensor assembly constructed in accordance with one example of the present disclosure;

FIG. 3 is a perspective view of a normally closed lock detection sensor assembly constructed in accordance with another example of the present disclosure;

FIG. 4A is a cross-sectional view of the lock detection sensor assembly taken along line 4-4 of FIG. 3 and shown in an open position;

FIG. 4B is a side view of the lock detection sensor assembly of FIG. 4A and shown in a closed position;

FIG. 5 is a perspective view of a normally open lock detection sensor assembly constructed in accordance with another example of the present disclosure and shown in a closed locked position;

FIG. 6 is a cross-sectional view of the lock detection sensor assembly taken along line 6-6 of FIG. 5;

FIG. 7 is a perspective view of the normally open lock detection sensor assembly of FIG. 5, and shown with the cover removed for illustration;

FIG. 8 is a cross-sectional view of the lock detection sensor assembly taken along line 8-8 of FIG. 7;

FIG. 9 is a perspective view of the lock detection sensor assembly of FIG. 5 and shown in an open, unlocked position;

FIG. 10 is a cross-sectional view of the lock detection sensor assembly taken along line 10-10 of FIG. 9; and is

Fig. 11 is a perspective view of the normally open lock detection sensor assembly of fig. 9, and shown with the cover removed for illustration.

Detailed Description

referring initially to FIG. 1, an electronic locking differential assembly constructed in accordance with the present disclosure is illustrated and generally identified at reference 10. The electronic locking differential assembly 10 can generally include a differential gear assembly or mechanism 20 disposed in a differential housing 22. The electronic locking differential assembly 10 is receivable in a housing (not shown) and is operative to drive a pair of axle shafts (not shown) connected to drive wheels (not shown).

The differential gear assembly 20 includes a pair of side gears 40 and 42 mounted for rotation with the axle shafts (and the first and second drive wheels). The side gears 40 and 42 define a first axle shaft opening 44 and a second axle shaft opening 46. A cross pin or pinion shaft 50 can be fixedly mounted to the differential case 22 for rotation therewith. A corresponding pair of pinion gears 52 are mounted for rotation with the pinion shaft 50 and are in meshing relationship with the two side gears 40 and 42.

it should be appreciated that under certain operating conditions, such as when the vehicle is turning or there is a slight difference in tire size, a certain amount of differentiating action may be permitted to occur between the side gears 40 and 42. However, according to the electronic locking differential assembly 10 of the present application, there is no clutch pack or other mechanism that merely delays or limits the differentiating action. In contrast, the electronic locking differential assembly 10 operates in either an unactuated, unlocked mode (effectively acting as an "opening differential") or an actuated, locked mode.

The electronic locking differential assembly 10 includes a locking actuation mechanism 70 that generally includes an armature 74 and a stator assembly 78. Armature 74 is guided by stator assembly 78. Stator assembly 78 includes an electromagnetic coil 80. The armature 74 is coupled to translate with the locking plate 84. The electronic locking differential assembly 10 is shown in an open state in FIG. 1, wherein the electromagnetic coil 80 is not energized (corresponding to an unactuated, unlocked state). When the solenoid coil 80 is energized, the armature 74 is caused to translate toward the solenoid coil 80, moving the locking plate 84 to the left as viewed in FIG. 1. The locking plate 84 causes the side gear 42 to be locked for simultaneous rotation with the side gear 40 corresponding to the locked state of actuation. Solenoid 80 is energized by a pair of electrical leads 90, also referred to herein as electrical input signals identifying lock actuation mechanism 70.

Referring now further to fig. 2 and 3, additional features of the electronic locking differential assembly 10 will be described. The electronic locking differential assembly 10 according to the present disclosure includes a lock detection mechanism 110. The lock detection mechanism 110 generally includes a first member 112 coupled to a carriage 116 that moves relative to a second member 120. In the example shown, the first member 112 is fixed for translation with the carriage 116. The carriage 116 is fixed for movement with the armature 74.

it can be appreciated that when the armature 74 is moved toward the electromagnetic coil 80 (i.e., when moving the differential gear assembly 20 to the actuated locked position), so is the carrier 116 and the first member 112. The first member 112 has a first terminal 130. The second member 120 includes a second terminal 132. When the first and second terminals 130, 132 are moved to predetermined positions relative to each other, the switch 140 closes and sends a signal to the controller 142 indicating the locked state of the electromagnetic locking differential assembly 10. The controller 142 can send a signal to the vehicle's instrument cluster 144 that the electromagnetic locking differential assembly 10 is locked to the driver. As identified above, in some examples, the electronic locking differential assembly 10 can remain locked even after de-energizing the coil 80 (in some examples, the driver is not known). In this regard, the electromagnetic locking differential 10 is able to remain locked, although the driver may have switched the electromagnetic locking differential 10 to the unlocked position. It can be appreciated that with the lock detection mechanism 110 of the present configuration, real-time assurance is provided that the electromagnetic locking differential assembly 10 is in the unlocked state for the drive.

According to an additional feature, the armature 74 is able to translate a first distance 150, whereby the switch 140 remains open. In one exemplary configuration, the first distance 150 can be 1.25 mm. The armature 74 is also able to translate a second distance 154 whereby the switch 140 is closed. In some examples, the switch 140 can be closed throughout the travel along the second distance 154. In one exemplary configuration, the second distance 154 can be 1.25 mm. Thus, the total gap 156 of the first and second distances 150, 154 is 2.5 mm. Other distances are contemplated and are within the scope of the present disclosure.

the shoulder bolt 170 can be threaded into a press pin pressed into the lock plate 84. Other configurations are contemplated that enable direct coupling of the armature 74 to the locking plate 84. The shoulder bolt 170 can produce direct translation to the locking plate 84 when the armature 74 is urged toward the electromagnetic coil 80. The biasing member 180 biases the first member 112 in a direction to the right toward the open position as viewed in fig. 2.

Turning now to fig. 3-4B, a lock detection mechanism 210 constructed in accordance with additional features is shown. The lock detection mechanism 210 is a mechanical switch that is normally closed. The lock detection mechanism 210 generally includes a first member 212 coupled to a carriage 216 that moves relative to a second member 220. The first member 212 is fixed for translation with the carriage 216. The carrier 216 is fixed for movement with the armature 74. It can be appreciated that when the armature 74 moves toward the electromagnetic coil 80, so does the carrier 216 and the first member 212. The first member 212 has a first terminal 230. The second member 220 includes a second terminal 232. When the first and second terminals 230, 232 are moved to predetermined positions relative to each other, the switch 240 opens and sends a signal to the controller 242 indicating the locked state of the electromagnetic locking differential assembly. The controller 242 is configured to send a signal to the vehicle's instrument set 244 conveying to the driver that the electromagnetic locking differential assembly 10 is locked.

According to an additional feature, the armature 74 is able to translate a first distance 250, whereby the switch 240 remains closed. In one exemplary configuration, the first distance 250 can be 1.25 mm. The armature 74 is also able to translate a second distance 254 whereby the switch 240 is opened. In some examples, the switch 240 can be open throughout travel along the second distance 254. In one exemplary configuration, the second distance 254 can be 1.25 mm. Thus, the total gap 256 of the first and second distances 150, 154 is 2.5 mm. Other distances are contemplated and are within the scope of the present disclosure. The biasing member 280 biases the first member 212 in a rightward direction toward the closed position as viewed in fig. 2.

Turning now to fig. 5-11, a lock detection mechanism 310 constructed in accordance with additional features is shown. The lock detection mechanism 310 is a mechanical switch that is normally open. The lock detection mechanism 310 is shown in the closed position in fig. 5-8 (corresponding to the differential assembly 10 in the actuated locked position). The lock detection mechanism 310 is in the open position of fig. 9-11 (corresponding to the differential assembly 10 being in the unactuated, unlocked position). The lock detection mechanism 310 generally includes a first member 312 in the form of a pawl that moves relative to a second member 320. The first member 312 is configured to rotate as the carriage 324 translates. In the example shown, a post 326 coupled to the bracket 324 forces a swing arm 328 fixed to a shaft 330 to rotate. The first member 312 then rotates with the shaft 330 and makes contact with the second member 320 when the switch 336 is closed in the closed position. The biasing member 334 forces the shaft 330 to rotate in a counterclockwise direction to the open position, as viewed in fig. 7. In this regard, the first member 312, the second member 320, and the biasing member 334 can collectively include a spring-loaded terminal 338.

The bracket 324 is fixed for movement with the armature 74. It can be appreciated that when the armature 74 moves toward the electromagnetic coil 80, so does the bracket 324 and the first member 312. When the switch 336 is closed, a signal is sent to the controller 342 indicating the locked state of the electromagnetic locking differential assembly 10. The controller 342 can send a signal to the vehicle's instrument cluster 344 that communicates to the driver that the electromagnetic locking differential assembly 10 is locked.

The foregoing description of these examples has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. Individual elements or features of a particular example are generally not limited to that particular example, but, where applicable, are interchangeable and can be used in a selected example, even if not specifically shown or described. Which can also be varied in many ways. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure.