阅读说明：本技术 一种无级变速器 (Stepless speed variator ) 是由 包木仁 王勇 梁文涛 于 2019-12-25 设计创作，主要内容包括：本发明公开了一种无级变速器,包括主动部分和从动部分以及设置在所述主动部分和从动部分之间的挠性元件,所述主动部分包括主动轴以及传动设置在所述主动轴上并用于夹持所述挠性元件的一对主动锥盘,所述从动部分包括从动轴以及传动设置在所述从动轴上用于夹持所述挠性元件的一对从动锥盘；在所述主动动锥盘的背面与轴向固定的限位件之间设置有弹性件,在所述从动定锥盘的背面设置有可轴向推动所述从动动锥盘的弹性调速机构,所述弹性件的倔强系数为K1,所述弹性调速机构的倔强系数为K2,且K1≥K2。本发明简化了无级变速器的调速方式,且提高调速速率,降低了成本。(The invention discloses a continuously variable transmission, which comprises a driving part, a driven part and a flexible element arranged between the driving part and the driven part, wherein the driving part comprises a driving shaft and a pair of driving conical disks which are arranged on the driving shaft in a transmission manner and used for clamping the flexible element; be provided with the elastic component between the back of initiative movable cone dish and the axially fixed locating part the back of driven fixed cone dish is provided with but axial promotion the elastic speed control mechanism of driven movable cone dish, the stubborn coefficient of elastic component is K1, the stubborn coefficient of elastic speed control mechanism is K2, and K1 is more than or equal to K2. The invention simplifies the speed regulation mode of the stepless speed changer, improves the speed regulation speed and reduces the cost.)

1. A continuously variable transmission comprises a driving part, a driven part and a flexible element arranged between the driving part and the driven part, wherein the driving part comprises a driving shaft and a pair of driving conical disks which are arranged on the driving shaft in a transmission mode and used for clamping the flexible element, and the driven part comprises a driven shaft and a pair of driven conical disks which are arranged on the driven shaft in a transmission mode and used for clamping the flexible element; one driving cone disk is a driving fixed cone disk fixed on the driving shaft, and the other driving cone disk can be axially fixed along the driving shaftGliding initiative moves the awl dish, and one of them driven awl dish is for fixing driven fixed cone dish on the driven shaft and relative with initiative fixed cone dish, and another driven awl dish is for can following driven shaft axial slip's driven cone dish and relative with initiative movable cone dish, its characterized in that: be provided with the elastic component between the back of initiative movable cone dish and axially fixed locating part the back of driven movable cone dish is provided with but axial promotion the elasticity speed adjusting mechanism of driven movable cone dish, the stubborn coefficient of elastic component is K₁The coefficient of stiffness of the elastic speed regulating mechanism is K₂And K is₁≥K₂。

2. The variable transmission of claim 1, wherein: the elastic speed regulating mechanism is wrapped by a hollow speed regulating screw and a speed regulating nut; the hollow speed regulation screw rod is connected with the driven shaft through a first bearing, one end of a speed regulation nut is connected with the driven cone disc through a second bearing, the other end of the speed regulation nut is provided with an internal thread and is in threaded connection with the external thread of the hollow speed regulation screw rod, the hollow speed regulation screw rod is limited in circumferential rotation through a fixed limiting block, the speed regulation nut is driven to rotate through a driving mechanism, and a disc spring assembly is sleeved on the driven shaft between the first bearing and the second bearing.

3. The continuously variable transmission according to claim 1 or 2, characterized in that: the elastic part is a disc spring assembly, the limiting part is a shaft sleeve fixed on the driving shaft, and the disc spring assembly is sleeved on the driving shaft.

4. The variable transmission of claim 3, wherein: the elastic member is composed of n disc springs, and has the following relationship that n is more than or equal to 4.

5. The continuously variable transmission of claim 3 or 4, wherein: the inner diameter of the disc spring is D, the outer diameter of the disc spring is D, the thickness of the disc spring is t, and the outer diameter of the conical disc is D₀And has the following relation, D < D₀+1，D/d<1.6，t>(D₀+1)/d。

6. The continuously variable transmission of claim 3, 4 or 5, wherein: a retainer ring is arranged between the disc springs with opposite openings, and the diameter of the retainer ring is d₀And the following conditions are satisfied: t/10 < d₀＜t。

7. The continuously variable transmission of claim 3, 4, 5 or 6, wherein: the speed regulating nut and the hollow speed regulating screw are of rolling spiral or sliding spiral structure, and the pitch diameter of the spiral structure is D_LAnd satisfies the following relationship: d_L＞D₀/2。

8. The continuously variable transmission of claim 2, 3, 4, 5, 6 or 7, wherein: the thread length L of the hollow speed regulating screw or the speed regulating nut meets the following relation: l > 2 (D)₀/2- D₀/3）tan(11π/180)。

9. The continuously variable transmission of claim 2, 3, 4, 5, 6, 7 or 8, wherein: the driving mechanism comprises a driving shaft, a driving gear is arranged at one end of the driving shaft, driven teeth meshed with the driving gear are arranged on the outer wall of the speed regulating nut, and the other end of the driving shaft is driven by a motor and a worm and gear mechanism.

10. The continuously variable transmission of claim 2, 3, 4, 5, 6, 7 or 8, wherein: the driving mechanism comprises a driving shaft, a turbine is arranged on the driving shaft, transmission teeth which are meshed with each other are arranged on the outer wall of the turbine and the outer wall of the speed regulating nut, and the turbine is driven by a motor and a worm.

Technical Field

The invention relates to a speed change mechanism, in particular to a continuously variable transmission.

Background

The Chinese patent CN201110193407.7 discloses a continuously variable transmission, and specifically discloses two parallel transmission shafts, wherein each of the two transmission shafts is provided with at least one pair of conical discs with conical surfaces oppositely arranged, at least one flexible transmission element is clamped between the conical discs, one conical disc in each pair of conical discs can axially move on the transmission shaft, and the other conical disc cannot axially move on the transmission shaft and can rotate along with the transmission shaft; the back of a conical disc which can axially move between a transmission shaft and the shaft is connected with a screw mechanism (a motor-driven speed regulating mechanism), the screw mechanism consists of a hollow screw and a nut matched with the hollow screw, and the transmission shaft is arranged in the hollow screw; one of the hollow screw rod and the nut of the screw mechanism is connected with the transmission shaft which belongs to the screw mechanism through a bearing which can bear axial load and radial load at the same time, and is directly connected with the conical disc which belongs to the screw mechanism and can move axially; the other one of the hollow screw and the nut is connected with the cone disc which is axially movable and belongs to the hollow screw and the nut through a bearing which can bear axial load and radial load simultaneously, and is directly connected with the transmission shaft which belongs to the hollow screw and the nut; one of the hollow screw and the nut is connected … … with a motor through a speed reducing mechanism, two cone discs which can move axially and are respectively positioned on the two transmission shafts are respectively connected with the cone discs through at least one end directly or indirectly, and the other end is directly or indirectly connected with a spring or a spring group on the transmission shaft of the cone disc and is pressed on the flexible transmission element and the fixed cone disc; wherein, the coefficient of stiffness or the total coefficient of stiffness of the conical disc connected with the speed-adjusting spiral mechanism and the spring or the spring group on the transmission shaft is larger than the coefficient of stiffness or the total coefficient of stiffness of the spring or the spring group on the other transmission shaft.

The above patent further provides one embodiment, in which a driven shaft pressing spring is arranged on the back of the driven shaft moving conical disc, and a motor driving speed regulating mechanism, namely a spiral speed regulating mechanism, is arranged on the back of the driving shaft moving conical disc. The coefficient of stiffness of the compression spring of the spiral speed regulating mechanism on the driving shaft is larger than that of the compression spring on the driven shaft.

With the continuously variable transmission in the above patent, there are the following problems: 1. the compression spring needs to be large in size and large in elasticity, and further the cone disc is too large in size. 2. When the speed is regulated, the speed is regulated by driving the spiral speed regulating mechanism with the motor no matter the transmission ratio is from large to small or from small to large, so that the motor with positive and negative rotation must be adopted, and the speed regulation is too slow by overcoming the elasticity of the spring. 3. The speed regulation system needs to coordinate the stiffness coefficients of the two groups of disc springs at the same time, so that the speed regulation is complex; and the speed regulation cone disc is subjected to bidirectional stress, so that the speed regulation is too slow for the speed regulation with small transmission ratio, and the bearing structure is complex, the cost is high and the space is large. 4. The change of the clamping force of the flexible transmission element during transmission is opposite to the change of the elastic force of the compression spring on the driven shaft, so that the speed regulation is slow and the speed regulation force is large.

Disclosure of Invention

The invention aims to provide a continuously variable transmission which is low in cost and simple and quick in speed regulation.

In order to achieve the above object, the present invention is realized by: a continuously variable transmission comprises a driving part, a driven part and a flexible element arranged between the driving part and the driven part, wherein the driving part comprises a driving shaft and a pair of driving conical disks which are arranged on the driving shaft in a transmission mode and used for clamping the flexible element, and the driven part comprises a driven shaft and a pair of driven conical disks which are arranged on the driven shaft in a transmission mode and used for clamping the flexible element; wherein a initiative awl dish is for fixing the initiative fixed cone dish on the driving shaft, and another initiative awl dish moves the awl dish for can following the initiative of driving shaft endwise slip, and one of them driven awl dish is for fixing driven fixed cone dish on the driven shaft and relative with initiative fixed cone dish, and another driven awl dish is for can following driven shaft endwise slip driven movable cone dish and relative with initiative fixed cone dish, its characterized in that: be provided with the elastic component between the back of initiative movable cone dish and axially fixed locating part the back of driven movable cone dish is provided with but axial promotion the elasticity speed adjusting mechanism of driven movable cone dish, the stubborn coefficient of elastic component is K₁The coefficient of stiffness of the elastic speed regulating mechanism is K₂And K is₁≥K₂. The stepless speed changer arranged in the mode has the advantages that the elastic speed regulating mechanism is arranged on the driven shaft, the elastic piece is arranged on the driving shaft, and the stiffness coefficient of the elastic speed regulating mechanism is set to be less than or equal to the stiffness coefficient of the elastic piece. When the speed is regulated from a large transmission ratio to a small transmission ratio, the driven movable conical disc is only pushed by the elastic speed regulation mechanismThe axial movement is enough, and the force applied by the flexible element is consistent with the change direction of the clamping force of the flexible element, so that the speed regulation speed is improved. When the speed is regulated from a small transmission ratio to a large transmission ratio, the elastic speed regulating mechanism does not need to apply force and only needs to push the driven movable conical disc to realize speed regulation through the axial return force of the elastic piece on the driving shaft. The speed regulating mechanism is simple, the speed regulating force requirement is low, and the speed regulating efficiency is high. In the continuously variable transmission arranged in the mode, the elastic speed regulating mechanism does not need to overcome the elastic force of the elastic speed regulating mechanism when returning, so that the elastic speed regulating mechanism and the elastic part can be designed to be smaller in volume and elastic force, the conical disc can be designed to be smaller, more parts can be saved, the cost of the continuously variable transmission is reduced, and the volume of the continuously variable transmission is reduced.

Preferably, the elastic speed regulating mechanism comprises a hollow speed regulating screw and a speed regulating nut; the hollow speed regulation screw rod is connected with the driven shaft through a first bearing, one end of a speed regulation nut is connected with the driven cone disc through a second bearing, the other end of the speed regulation nut is provided with an internal thread and is in threaded connection with the external thread of the hollow speed regulation screw rod, the hollow speed regulation screw rod is limited in circumferential rotation through a fixed limiting block, the speed regulation nut is driven to rotate through a driving mechanism, and a disc spring assembly is sleeved on the driven shaft between the first bearing and the second bearing.

Preferably, the elastic part is a disc spring assembly, the limiting part is a shaft sleeve fixed on the driving shaft, and the disc spring assembly is sleeved on the driving shaft.

In order to further realize the speed regulation range of the transmission ratio, the elastic element is composed of n disc springs, and the relation n is more than or equal to 4. This way a range of 0.5-2 four times the transmission ratio requirement can be achieved.

In order to further realize the speed regulation range of the transmission ratio, the inner diameter of the disc spring is D, the outer diameter of the disc spring is D, the thickness is t, and the outer diameter of the conical disc is D₀And has the following relation, D < D₀+1，D/d<1.6，t>(D₀+ 1)/d. By such an arrangement, a curve of axial force requirements can be achieved, achieving maximum to minimum gear ratios.

To further ensure the speed regulation range and the stability of the disc spring, the openingA retainer ring is arranged between the disc springs with opposite openings, and the diameter of the retainer ring is d₀And the following conditions are satisfied: t/10 < d₀< t. The thickness of the retainer ring is too large to affect the transmission ratio range, resulting in a reduction of the transmission ratio range, and too small to affect the force stability of the disc spring, so that selection of a particular thickness is required.

In order to further prolong the service life of the transmission, the speed regulating nut and the hollow speed regulating screw are of rolling spiral or sliding spiral structures, wherein the diameter is D_LAnd satisfies the following relationship: d_L＞D₀/2。

In order to further realize the speed regulation range, the thread length L of the hollow speed regulation screw or the speed regulation nut meets the following relationship: l > 2 (D)₀/2- D₀/3）tan(11π/180)。

In order to further reduce the space of the transmission, the driving mechanism comprises a driving shaft, one end of the driving shaft is provided with a driving gear, driven teeth meshed with the driving gear are arranged on the outer wall of the speed regulating nut, and the other end of the driving shaft is driven by a motor and a worm and gear mechanism. The motor drives the worm, the worm drives the worm wheel to rotate, the worm wheel further drives the driving gear on the driving shaft to rotate, and the speed regulating nut is driven due to meshing with the driving gear.

In order to further reduce the space of the transmission, the driving mechanism comprises a driving shaft, a turbine is arranged on the driving shaft, the outer wall of the turbine and the outer wall of the speed regulating nut are provided with transmission teeth which are meshed with each other, and the turbine is driven by a motor and a worm. The motor drives the worm, the worm drives the worm wheel to rotate, and the worm wheel further drives the speed regulating nut to rotate, so that the axial movement of the speed regulating nut is realized.

Has the advantages that:

according to the invention, through structure adjustment, the elastic speed regulating mechanism is arranged on the back of the driven movable conical disc of the driven shaft, and the disc spring assembly is arranged on the back of the driving movable conical disc of the driving shaft for matching, so that the speed adjustment of the whole transmission is realized. And the coefficient of stiffness of the disc spring assembly of the elastic speed regulating mechanism is set to be less than or equal to the coefficient of stiffness of the disc spring assembly on the driving shaft. Therefore, the speed regulation mode of the stepless speed changer is simplified, the speed regulation speed is improved, the speed regulation force required by the elastic speed regulation mechanism is reduced, and the power required by the speed regulation motor is further reduced. The space arrangement of the transmission is optimized, the size and parts of the transmission are reduced, and the cost is reduced.

Specifically, the method comprises the following steps: 1. in the stepless speed changer, in the speed regulation process of which the transmission ratio is reduced from high to low, only the elastic speed regulation mechanism is needed to pressurize the driven dynamic conical disc, and the force applied by the elastic speed regulation mechanism is consistent with the change direction of the clamping force required by the flexible element, so that the speed regulation speed is improved, and the force required by a speed regulation motor is reduced. In the speed regulation process of the transmission ratio from small to large, the elastic speed regulation mechanism does not need to apply force, and only needs to transmit the axial return force of the disc spring assembly on the driving movable conical disc to the driven movable conical disc through the flexible element, so that the driven movable conical disc is axially pushed to realize the increase of the transmission ratio. In the process, additional stress is not required to be applied to the elastic speed regulating mechanism through the speed regulating motor, and the elastic force of a disc spring on the elastic speed regulating mechanism is not required to be overcome, so that the speed regulating speed is high. Therefore, the speed regulation force is reduced by reasonably configuring the disc spring, and the speed regulation is faster for small transmission ratio and direction.

2. Through the design of the speed regulating mechanism and the disc spring assembly, the force required to be overcome by the driven dynamic cone disc is small in the speed regulating process, the stress condition of the driven dynamic cone disc is consistent with the change direction of the clamping force of the flexible element, and overlarge elastic force does not need to be designed for the disc spring, so that the design volume of the cone disc is further reduced, and the overall volume of the continuously variable transmission is reduced.

3. The stepless speed changer has simple speed regulation structure, the conical disc driven by the speed regulation mechanism is changed into unidirectional stress from bidirectional stress, the bearing type is simplified, the positioning mode is simplified, and the cost is reduced.

Drawings

FIG. 1 is a block diagram of a continuously variable transmission of the present invention;

fig. 2 is a partially enlarged view of fig. 1.

Detailed Description

The following detailed description of the embodiments of the present invention will be made with reference to the accompanying drawings, but the present invention is not limited to these embodiments, and any modifications or substitutions in the basic spirit of the embodiments will still fall within the scope of the present invention as claimed in the claims.