KR100476945B1 - Speed ratio control mechanism of a variator - Google Patents

Abstract

The present invention relates to a speed ratio control apparatus of a continuously variable transmission.

In order to change the effective radius of the driving pulley and the driven pulley, the linear movement of the movable pulley piece is used as the ball screw, and the rotation of the ball screw is controlled by using one or more planetary gear units and two motors. The force in the same direction is transmitted to bring the belt into close contact at the same time, and the other motor transmits the force in the opposite direction to the two pulleys.

The speed ratio control apparatus as described above has high efficiency due to low power consumption, and can cope with a change in direction of power transmission.

Description

Speed ratio control mechanism of a continuously variable transmission

The present invention relates to a speed ratio control device for adjusting the width ratio of a pulley of a continuously variable transmission consisting of a pulley and a belt, and consequently adjusting the speed ratio.

The pulley is composed of a fixed pulley piece fixed to a rotating shaft and having an inclined surface, and a movable pulley piece facing the same axis as the fixed pulley piece and movable in the axial direction, and moving the movable pulley piece in the axial direction between the inclined surfaces of the two pulley pieces. The effective radius of the belt caught on the side will change. By controlling the effective radii of the two pulleys respectively provided on the drive shaft and the driven shaft, the rotational speed ratio of the two shafts can be controlled.

One of the methods for moving the movable pulley piece along the axis is a converter mechanism using the ball screw 8 as shown in FIG. The ball screw 8 is composed of a screw that is a fixing part 82, a nut that is a rotating part 81, and a spherical or cylindrical roller 83 that is placed between the fixing part and the rotating part to perform a frictional friction, and the rotating part 81 Rotating moves the rotating part also in the axial direction. The first intermediate gear 15 is formed as one body in the rotating unit 81, and the rotation of the first motor 61 is transmitted through the reducer 27 and the second intermediate gear 17. You can also rotate the screw and secure the nut. When the housing of the bearing 9 supporting the movable pulley piece 4 in the axial direction and the rotary part 81 are integrated, the force for rotating the rotary part 81 is independent of the rotational speed of the pulley. ) Is converted into a pushing force. A spring 28 is used instead of the ball screw 8 to prevent the belt 1 from loosening.

In the conventional speed ratio control apparatus as described above, the power of the first motor 61 is determined by the speed of moving the movable pulley piece 4 and the force pushing the movable pulley piece. Therefore, heavy and large motors must be used and power consumption is high. In addition, it is difficult to change the functions of the drive shaft and the driven shaft because the pulley is generated in a way that the pulley close to the belt in the drive shaft and the driven shaft.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a control device capable of controlling the speed ratio with a small power and changing the function of the drive shaft and the coaxial shaft.

In order to achieve the above object, the present invention is composed of two shafts and a belt parallel to each other provided with two pulleys each consisting of a fixed pulley piece fixed in the axial direction and a movable pulley piece movable in the axial direction and between the two shafts A speed ratio control apparatus for a continuously variable transmission that transmits power at a continuous speed ratio, comprising: a bearing for supporting the movable pulley piece in an axial direction; Two converter mechanisms each comprising a rotating part for supporting the bearing, a fixed part fixed to the housing, and a roller placed between the rotating part and the fixed part, respectively provided on the two shafts; A planetary gear device comprising a sun gear, a first reduction element, and a second reduction element, wherein the first and second reduction elements are respectively connected to rotate the rotation parts of the two converter mechanisms; A first motor connected to rotate the sun gear; And a second motor connected to rotate the first deceleration element, wherein the first motor causes the two pulleys to simultaneously apply a force for close contact with the belt, and the second motor has only one pulley belt. It is characterized in that to apply a force close to the.

In addition, a bearing for supporting the movable pulley piece in the axial direction; Two converter mechanisms each comprising a rotating part for supporting the bearing, a fixed part fixed to the housing, and a roller placed between the rotating part and the fixed part, respectively provided on the two shafts; A first planetary gear device comprising a sun gear, a first reduction element, and a second reduction element, wherein the first and second reduction elements are respectively connected to rotate the rotating portions of the two converter mechanisms; A second planetary gear device comprising a sun gear, a first reduction element, and a second reduction element, wherein the first and second reduction elements are respectively connected to rotate the first and second reduction elements of the first planetary gear device; A first motor connected to rotate the sun gear of the first planetary gear device; And a second motor connected to rotate the sun gear of the second planetary gear device, wherein the first motor causes the two pulleys to simultaneously apply a force for close contact with the belt, and the second motor has one It is characterized in that the pulley only to apply a force to close the belt.

In addition, the speed ratio control device of a continuously variable transmission comprising two shafts and a belt parallel to each other provided with a pulley composed of two movable pulley pieces that can move in the axial direction, and transfers power at a continuous speed ratio between the two shafts. An internal gear that rotates integrally with one axis; An external gear which rotates integrally with one movable pulley piece; A first planetary gear device comprising a first reduction element for engaging the internal gear, a second reduction element for engaging the external gear, and a sun gear; A third planetary gear device configured on the other axis in the same manner as the first planetary gear device; A first motor assembled to drive the sun gear of the first planetary gear device; A second planetary gear device including a first reduction element that is integrally rotated with the sun gear of the third planetary gear device, a second reduction element that receives rotation of the first motor through an intermediate gear, and a sun gear; And a second motor assembled to drive the sun gear of the second planetary gear device, wherein the second motor causes the two pulleys to simultaneously apply a force for close contact with the belt, and the first motor has only one pulley. It is characterized by applying a force for close contact with the belt.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

2 is a configuration diagram showing the outline of the first embodiment. The fixed pulley pieces 3 and 5 and the movable pulley pieces 4 and 6 are provided in the drive shaft 1 and the driven shaft 2 which are parallel to each other, and the movable pulley pieces 4 and 6 are bearings 9, respectively. And the ball screw 8 in the axial direction. The first intermediate gears 15 and 16 are fixed to the rotating portion of the ball screw 8. There is a planetary gear device 10 composed of a sun gear 11, a pinion gear 12, a ring gear 13 and a carrier 14, the second intermediate gear 17 integral with the carrier 14 is a drive shaft ( An external gear meshed with the first intermediate gear 15 of 1) and integral with the ring gear 13 meshes with the third intermediate gear 19 and rotates integrally with the third intermediate gear 19. The dual intermediate gear 18 meshes with the first intermediate gear 16 of the driven shaft 2. The first motor 61 is connected to the sun gear 11 through the speed reducer 26 as needed, and the second motor 62 is connected to the sun gear 11 through the speed reducer 27 as necessary. Is connected to. It is preferable that the respective reduction ratios from the sun gear 11 to the two first intermediate gears 15 and 16 are the same.

When a driving force is generated in the first motor 61, the amplified force is transmitted to the sun gear 11 through the reducer 26, and the amplified force is further transmitted to the first gear via the carrier 14 and the second intermediate gear 17. It acts as a force to rotate the intermediate gear 15. Further, the force of the sun gear 11 is weaker than that of the carrier 14 and is amplified by the force to rotate in the opposite direction to act on the ring gear 13. The force of the ring gear 13 acts on the first intermediate gear 16 via the third and second intermediate gears 19 and 18. When the screw directions of the two ball screws 8 are reversed, the force of the first motor 61 acts simultaneously in the direction in which the pulley is in close contact with the belt 7 on the two movable pulley pieces 4, 6. In order to equalize the screw direction of the two ball screws 8, two gears which add or engage one more intermediate gear in one of the power transmission processes from the sun gear 11 to the two first intermediate gears 15 and 16. It can be replaced by a belt instead.

When the second motor 62 rotates, the two movable pulley pieces 4 and 6 simultaneously move, and it is preferable to select the number of teeth of the gears so that the two moving amounts are the same. When driving the second motor 62 to change the speed ratio from minimum to maximum, the effective radius of the driving pulley increases and the effective radius of the driven pulley decreases, but the movement amount of the two movable pulley pieces 4 and 6 is not the same. Instead, the movement amount of the smaller radius can be maintained to be in close contact with the pulley. The rotation of the first motor 61 compensates for the difference in movement amount generated at this time. The force of the second motor 62 is amplified through the reduction gear 27 and added to the force of the third intermediate gear 19. The axial force acting on the movable pulley piece 6 of the driven shaft 2 is the sum of the two forces if the directions of the forces generated by the first motor 61 and the second motor 62 are the same, If the direction is reversed, it is the difference between the two forces. The moving speed of the two movable pulley pieces 4, 6 is determined by the rotational speed of the second motor 62, and the force depends on the speed ratio and the inclination of the pulley, It is about one third of the maximum force acting in the direction. Therefore, the size of the second motor 62 is approximately one third of the conventional motor.

The difference in the movement amount of the two movable pulley pieces 4 and 6 is approximately 1/20 of the movement amount of the movable pulley piece, and the maximum magnitude of the force by the first motor 61 is equal to the maximum force acting in the axial direction on the pulley. The size of the first motor 61 is approximately 1/20 of the motor used conventionally.

The planetary gear apparatus 10 described above uses the sun gear 11 as an input means, and uses the ring gear 13 and the carrier 14 as decelerated output means. In order to achieve a large reduction ratio, the pinion gear can have two teeth on one body, the sun gear can be engaged with the larger diameter, and the ring gear can be engaged with the smaller diameter. If the positions of the carrier 14 and the ring gear 13 are interchanged with each other, the same result can be obtained by changing the rotation direction of the motor or the screw direction of the ball screw. Call it an element. As shown in FIG. 4, two sun gears, two pinion gears, and two ring gears are rotated integrally, two sun gears rotate integrally, and two pin gears have two ring gears without carriers. It functions as the first and second deceleration elements.

3 is a configuration diagram showing an outline of a second embodiment. With all the components shown in FIG. 2, the second sun gear 21, the second pinion gear 22, the second ring gear 23 and the second between the second motor 62 and the third intermediate gear 19. A second planetary gear device 20 composed of a carrier 24 is added, and a fourth intermediate gear 25 formed integrally with the first carrier 14 of the first planetary gear device is configured. The second carrier 24 is integrally formed with the third intermediate gear 19, and the external gear formed on the second ring gear 23 passes through the fourth intermediate gear 25 via another intermediate gear not shown in the drawing. ). The first motor 61 is connected to the first sun gear 11 via the reducer 26, and the second motor 62 is connected to the second sun gear 21 via the reducer 27. In most cases driven by electricity, the first motor 61 requires the speed reducer 26, but the second motor 62 may not need the speed reducer 27. It is preferable that the two reduction ratios from the first sun gear 11 to the first intermediate gears 15 and 16 are equal to each other, and the two reduction ratios from the second sun gear 21 to the first intermediate gears 15 and 16 are equal to each other. It is preferable that the sign is different. Since the carrier and the ring gear have the concept of the first and second reduction elements as described above, their positions can be changed.

When the driving force is generated in the first motor 61, the pulley acts on the two moving pulley pieces 4 and 6 in the direction in which the belt 7 is in close contact with each other as in the first embodiment. Since the maximum magnitude of the force by the first motor 61 is smaller than the maximum force acting on the pulley by the second motor 62 and the movement amount is the same, the magnitude of the first motor 61 is equal to It can be smaller than the motor used in the first embodiment.

The force of the second motor 62 is amplified and added to the force of the third intermediate gear 19 via the second carrier 24, and the force of the second ring gear 23 is in the opposite direction and thus is not shown in the figure. It is added to the fourth intermediate gear 25 via another intermediate gear. The force generated by the second motor 62 and transmitted to the two pulleys is added to the force generated by the first motor 61 on one axis and reduced on the other axis. The size of the second motor 62 is approximately one third of the motor conventionally used as in the first embodiment.

In the first and second embodiments, the screw direction of the ball screw 8 is preferably a direction in which the rotational resistance of the bearing 9 is converted into a force pushing the movable pulley pieces 4 and 6.

4 is a cross-sectional view showing the configuration of the third embodiment. The drive shaft 1 is provided with a first movable pulley piece 41 that rotates like a drive shaft and is movable in the axial direction, and the second movable pulley piece 41 is rotatable with a drive shaft and is movable in the axial direction. The movable pulley piece 42 is installed and the fixing part 82 of the ball screw 8 is fixed. The rotating part 81 of the ball screw 8 applies the axial force to the said 2nd movable pulley piece through the bearing 9 as a medium. The first external gear 51 is formed at one end of the rotary part 81, and the second internal gear 53 is formed at one end of the drive shaft 1. Two first sun gears 11-1 and 11-2 formed in one body and two first pinion gears 12-1 and 12-2 meshing with the first sun gear 11 and sharing the rotation axis, respectively. ) And a first planetary gear device 10 composed of two first ring gears 13-1 and 13-2 engaged with the first pinion gear 12. 13-1) is formed with a first internal gear 52 meshing with the first external gear 51, and the second internal gear 53 on the outside of the other first ring gear 13-2. ) Is engaged with the second external gear 54. The driven shaft 2 arranged parallel to the drive shaft 1 also has a pulley, a bearing 9, a ball screw 8, an internal gear 53, an external gear 51 and a third planetary gear in the same manner as the drive shaft. The device 30 is installed. The second planetary gear device 20 having the same configuration as the first planetary gear device 10 is disposed on the same line as the driven shaft 2, and one second ring gear 23-2 is connected to the third sun gear ( 31 is integrally coupled with the other second ring gear 23-1 so as to interlock with the rotation of the first sun gear 11 via the intermediate gear 55. The first motor 61 is connected to drive the first sun gear 11, and the second motor 62 is connected to drive the second sun gear 21.

The number of gears of the first planetary gear device described above includes 16 first sun gears 11-1, 18 first pinion gears 12-1, 52 first ring gears 13-1, and first sun gears. (11-2) Assuming 18, 16 first pinion gears 12-2 and 50 first ring gears 13-2, the other when one first ring gear 13-1 is fixed The first ring gear 13-2 has a reduction ratio of -25 with respect to the first sun gear 11, and one first ring gear 13-1 when the other first ring gear 13-2 is fixed. Has a reduction ratio of 26 with respect to the first sun gear 11. The number of teeth of the first internal gear 52 is 52, the number of teeth of the first external gear 51 is 51, the number of teeth of the second external gear 54 is 50 and the number of teeth of the second internal gear 53 is 53. If 51 is assumed, when the drive shaft 1 rotates without the relative rotation of the ball screw 8, the speed of one first ring gear 13-1 is different from the first ring gear 13-2. It's 25/26 of speed. Therefore, the rotation of the first sun gear 11 is independent regardless of the rotation of the drive shaft 1, and when the first motor 61 rotates, the rotation part 81 of the ball screw 8 has a reduction ratio of 25.5 (= 51/52). The relative rotation of the speed decelerated by * 26 occurs, and the effective radius of the pulley is changed.

The number of teeth of the gear of the second planetary gear device is the same as the number of teeth of the gear of the first planetary gear device, and the rotation of the first sun gear 11 is reduced to -26/25 by one second ring gear 23-1. If transmitted, when the second motor 62 is stopped, the rotation of the third sun gear 31 rotates in the opposite direction to the first motor 61 and the rotation speed is the same. Therefore, the rotation of the first motor 61 changes the effective radius of the two pulleys in the opposite direction, and when the pulley acts as a force for close contact with the belt at one pulley, the other pulley acts as a force to isolate the belt. When the second sun gear 21 rotates, the force amplified by the reduction gear ratio of -25 by one second ring gear 23-2 is amplified by the reduction gear ratio of 25.5 to act on the rotating part 81 of the driven shaft 1. The force amplified by the reduction gear ratio of 26 to the other second ring gear 23-1 is transmitted to the reduction gear ratio of -25/26 to the first sun gear 11, and amplified by the reduction gear ratio of 25.5 to the rotating part of the drive shaft 1. Acts on (81). Therefore, the force of the second motor 62 acts simultaneously on both axes in the direction in which the pulley is in close contact with the belt.

The ring gears of the first, second, and third planetary gear devices 10, 20, and 30 are decelerated output means as described above, and thus may be replaced with other types of planetary gear devices. Further, the first movable pulley piece may be integrally formed with the shaft, the driving shaft and the driven shaft may be replaced with each other, or the positions of the second internal gear 53 and the first external gear 51 may be changed to perform the same function. It can also be configured. Although the ball screw and the first planetary gear device respectively installed in the driving pulley and the driven pulley are not the same, it is disadvantageous because the parts cannot be shared.

Therefore, the speed ratio control apparatus as in the above embodiment greatly reduces the power consumption and heat generation, thereby increasing the overall efficiency, and it is possible to cope even if the power flow direction is changed from the driven shaft 2 to the drive shaft 1.

As mentioned above, although this invention was demonstrated in detail through the specific Example, this invention is not limited to the said Example, A various deformation | transformation is possible for a person with ordinary knowledge within the scope of the technical idea of this invention.

The speed ratio control device as described above has a low power consumption, high efficiency, and can cope with a change in direction of power transmission.

1 is a view showing a conventional speed ratio control device.

2 is a view showing a speed ratio control apparatus according to a first embodiment of the present invention.

3 is a view showing a speed ratio control apparatus according to a second embodiment of the present invention.

4 is a view showing a speed ratio control apparatus according to a third embodiment of the present invention.

<Explanation of symbols for the main parts of the drawings>

1: drive shaft 2: driven shaft

3, 5: fixed pulleys 4, 6: movable pulleys

7: belt 8: ball screw

9: bearing 10: first planetary gear unit

11: First Sun Gear 12: First Pinion Gear

13: First Ring Gear 14: First Carrier

15,16: 1st intermediate gear 17,18: 2nd intermediate gear

19: 3rd intermediate gear 20: 2nd planetary gear device

21: 2nd Sun Gear 22: 2nd Pinion Gear

23: second ring gear 24: second carrier

25: 4th intermediate gear 26, 27: Reducer

28: spring 30: third planetary gear device

31: 3rd Sun Gear 32: 3rd Pinion Gear

33: third ring gear 41: first movable pulley

42: second movable pulley 51: first external gear

52: 1st internal gear 53: 2nd internal gear

54: second external gear 55: intermediate gear

61: first motor 62: second motor

81: rotating part 82: fixed part

83: roller

Claims (3)

An endless pulley composed of two parallel shafts and a belt provided with two pulleys each comprising a fixed pulley piece fixed in the axial direction and a movable pulley piece movable in the axial direction, and transferring power between the two axes at a continuous speed ratio. In the speed ratio control apparatus of the transmission, A bearing for supporting the movable pulley piece in an axial direction; Two converter mechanisms each comprising a rotating part for supporting the bearing, a fixed part fixed to the housing, and a roller placed between the rotating part and the fixed part, respectively provided on the two shafts; A planetary gear device comprising a sun gear, a first reduction element, and a second reduction element, wherein the first and second reduction elements are respectively connected to rotate the rotation parts of the two converter mechanisms; A first motor connected to rotate the sun gear; A second motor connected to rotate the first deceleration element, The first motor causes the two pulleys to simultaneously apply a force for close contact with the belt, The second motor is a speed ratio control device, characterized in that to apply a force to close the belt only one pulley. An endless pulley composed of two parallel shafts and a belt provided with two pulleys each comprising a fixed pulley piece fixed in the axial direction and a movable pulley piece movable in the axial direction, and transferring power between the two axes at a continuous speed ratio. In the speed ratio control apparatus of the transmission, A bearing for supporting the movable pulley piece in an axial direction; Two converter mechanisms each comprising a rotating part for supporting the bearing, a fixed part fixed to the housing, and a roller placed between the rotating part and the fixed part, respectively provided on the two shafts; A first planetary gear device comprising a sun gear, a first reduction element, and a second reduction element, wherein the first and second reduction elements are respectively connected to rotate the rotating portions of the two converter mechanisms; A second planetary gear device comprising a sun gear, a first reduction element, and a second reduction element, wherein the first and second reduction elements are respectively connected to rotate the first and second reduction elements of the first planetary gear device; A first motor connected to rotate the sun gear of the first planetary gear device; It is composed of a second motor connected to rotate the sun gear of the second planetary gear device, The first motor causes the two pulleys to simultaneously apply a force for close contact with the belt, The second motor is a speed ratio control device, characterized in that to apply a force to close the belt only one pulley. In the speed ratio control apparatus of the continuously variable transmission comprising two shafts and a belt parallel to each other provided with a pulley composed of two movable pulley pieces that can move in the axial direction and transmits power at a continuous speed ratio between the two shafts. , A bearing for supporting one movable pulley piece in an axial direction; Two converter mechanisms each of which comprises a rotating part for supporting the bearing, a fixed part fixed to the other movable pulley piece, and rollers disposed between the rotating part and the fixed part; An internal gear that rotates integrally with the shaft; An external gear which rotates integrally with one movable pulley piece; A first planetary gear device comprising a first reduction element for engaging the internal gear, a second reduction element for engaging the external gear, and a sun gear; A third planetary gear device configured on the other axis in the same manner as the first planetary gear device; A first motor assembled to drive the sun gear of the first planetary gear device; A second planetary gear device including a first reduction element that is integrally rotated with the sun gear of the third planetary gear device, a second reduction element that receives rotation of the first motor through an intermediate gear, and a sun gear; A second motor assembled to drive the sun gear of the second planetary gear device; The second motor causes the two pulleys to simultaneously apply a force for close contact with the belt, The first motor is a speed ratio control device, characterized in that to apply a force to close the belt only one pulley.