JP6329643B2 - Transmission pulley - Google Patents

Description

  According to the present invention, a pulley disposed on a rotation shaft supported by a transmission case via a bearing and on which an endless belt is wound is fixed to a stationary pulley half fixed to the rotation shaft, and the rotation shaft. A movable pulley half supported so as not to be relatively rotatable and movable in the axial direction, a cylindrical cylinder protruding in the axial direction from the back surface of the movable pulley half, and immovable in the axial direction with respect to the rotating shaft The present invention relates to a transmission pulley including an annular piston that is supported and has an outer peripheral portion slidably fitted into the cylinder, and a pulley oil chamber defined between the cylinder and the piston.

  The transmission pulley described in FIG. 3 of the following Patent Document 1 has a pulley on the movable side of a pulley between a step portion formed in the middle in the axial direction of the rotating shaft and a nut screwed to the shaft end of the rotating shaft. The piston and the gear are fixed to the rotating shaft by sandwiching the inner peripheral portion of the piston that drives the body and the boss portion of the power transmission gear and fastening them in the axial direction.

Japanese Patent No. 4048453

  By the way, in the above-mentioned conventional one, the inner peripheral part of the piston and the boss part of the gear are sandwiched and fastened between the step part of the rotary shaft and the nut. Not only does the axial dimension increase, but a large bending moment acts in the vicinity of the inner periphery of the piston that is fixed to the rotating shaft by the oil pressure in the pulley oil chamber. It was necessary to use a strong material.

  The present invention has been made in view of the above circumstances, and by integrating the piston of the transmission pulley and the transmission gear, the axial dimension of the transmission is reduced and the bending moment acting on the piston is reduced. It aims at reducing.

  In order to achieve the above object, according to the present invention, a pulley on which a pulley that is disposed on a rotating shaft supported by a transmission case via a bearing and on which an endless belt is wound is fixed to the rotating shaft. A half body, a movable pulley half supported so as not to be rotatable relative to the rotating shaft and axially movable, a cylindrical cylinder projecting in the axial direction from the back surface of the movable pulley half, and An annular piston that is supported so as not to move in the axial direction with respect to the rotating shaft and whose outer peripheral portion is slidably fitted to the inner peripheral surface of the cylinder; a pulley oil chamber defined between the cylinder and the piston; A pulley for a transmission comprising: a nut bossed between the step formed on the rotating shaft and the inner race of the bearing and screwed to the rotating shaft; Between the inner And a protruding portion that protrudes in the axial direction toward the cylinder on the side wall portion of the gear, and an inner peripheral portion of the piston is fitted to an outer peripheral surface of the protruding portion to A transmission pulley having a first feature of being attached to a side wall is proposed.

  According to the present invention, in addition to the first feature, there is proposed a transmission pulley having a second feature that the piston is made of synthetic resin.

  According to the invention, in addition to the first or second feature, a third feature is that a plurality of first ribs extending radially in the radial direction are provided on the back surface of the piston. A pulley is proposed.

  Further, according to the present invention, in addition to the third feature, a fourth aspect is that the annular second rib extending in the circumferential direction on the back surface of the piston and connecting the plurality of first ribs is provided. A transmission pulley having the following characteristics is proposed.

  The first auxiliary input shaft 13A of the embodiment corresponds to the rotating shaft of the present invention, the first pulley 21 of the embodiment corresponds to the pulley of the present invention, and the first fixed-side pulley half of the embodiment. 21A corresponds to the fixed pulley half of the present invention, the first movable pulley half 21B of the embodiment corresponds to the movable pulley half of the present invention, and the second reduction gear 26 of the embodiment corresponds to this Corresponding to the gear of the invention, the ball bearing 42 of the embodiment corresponds to the bearing of the invention.

  According to the first feature of the present invention, a pulley disposed on a rotating shaft supported by a transmission case via a bearing and on which an endless belt is wound is a fixed pulley half fixed to the rotating shaft, A movable pulley half supported so as not to be rotatable relative to the rotating shaft and movable in the axial direction, a cylindrical cylinder protruding in the axial direction from the back surface of the movable pulley half, and an axial direction relative to the rotating shaft Since it includes an annular piston that is supported so as not to move and whose outer peripheral portion is slidably fitted to the cylinder, and a pulley oil chamber defined between the cylinder and the piston, the hydraulic pressure supplied to the pulley oil chamber is controlled. Thus, the gear ratio can be changed by moving the movable pulley half closer to or away from the fixed pulley half.

  The gear boss is sandwiched between the step formed on the rotating shaft and the inner race of the bearing, and the inner race and the boss are fastened between the nut and the step that are screwed to the rotating shaft. Since the projecting part that protrudes in the axial direction toward the cylinder is provided on the part, and the inner peripheral part of the piston is fitted to the outer peripheral surface of the projecting part and applied to the side wall part, the inner peripheral part of the piston is It is no longer necessary to sandwich the gap between the gear and the boss of the gear, and the axial dimension of the transmission can be shortened by the thickness of the inner peripheral portion of the piston, and the number of parts fastened by the nut is reduced. This improves the reliability against loosening of the nut.

  Moreover, not only can the piston be made smaller and lighter by the reduction in the diameter of the inner periphery of the piston, but the load acting on the inner periphery of the piston applied to the side wall of the gear is Since the bending moment decreases mainly due to the axial force, it is possible to reduce the cost by using a low-strength material for the piston.

  According to the second feature of the present invention, since the piston is made of synthetic resin, it is possible to reduce the weight of the piston and increase the degree of freedom in shape.

  According to the third feature of the present invention, since the plurality of first ribs extending radially in the radial direction are provided on the back surface of the piston, the rigidity of the piston can be increased by the first rib.

  According to the fourth aspect of the present invention, since the annular second rib that extends in the circumferential direction and connects the plurality of first ribs is provided on the back surface of the piston, the first rib and the second rib The rigidity of the piston can be further increased by cooperation.

FIG. 1 is a skeleton diagram of a continuously variable transmission. (First embodiment) FIG. 2 is a detailed view of part 2 of FIG. (First embodiment) FIG. 3 corresponds to FIG. (Second Embodiment)

13A First auxiliary input shaft (rotary shaft)
13Aa Step 21 First pulley (pulley)
21A First fixed pulley half (fixed pulley half)
21B First movable pulley half (movable pulley half)
23 Endless belt 26 Second reduction gear (gear)
26a Boss part 26b Side wall part 26d Protrusion part 41 Transmission case 42 Ball bearing (bearing)
42a Inner race 44 Nut 48 Cylinder 49 Piston 49a Outer peripheral part 49b Inner peripheral part 49c First rib 49d Second rib 52 Pulley oil chamber

  Hereinafter, a first embodiment of the present invention will be described with reference to FIG. 1 and FIG.

First embodiment

  As shown in FIG. 1, a continuously variable transmission T mounted on a vehicle is arranged in parallel to a main input shaft 13 connected to a crankshaft 11 of an engine E via a torque converter 12 and to the main input shaft 13. The first auxiliary input shaft 13A, the second auxiliary input shaft 13B, the auxiliary shaft 14, the output shaft 15 and the idle shaft 16 are provided. The cylindrical auxiliary shaft 14 is fitted on the outer periphery of the main input shaft 13 so as to be relatively rotatable. The cylindrical output shaft 15 is fitted to the outer periphery of the first auxiliary input shaft 13A so as to be relatively rotatable.

  A first reduction gear 25 supported on the main input shaft 13 so as to be relatively rotatable and a second reduction gear 26 fixed to the first auxiliary input shaft 13A mesh with each other, and the first reduction gear 25 is a LOW friction clutch 24A. Can be coupled to the main input shaft 13. Further, a first induction gear 27 fixed to the main input shaft 13 and a second induction gear 28 supported so as to be relatively rotatable with respect to the second auxiliary input shaft 13B mesh with each other, and the second induction gear 28 is HI friction clutch 24B. Can be coupled to the second auxiliary input shaft 13B via

  The belt-type continuously variable transmission mechanism 20 disposed between the first sub input shaft 13A and the second sub input shaft 13B includes a first pulley 21 provided on the first sub input shaft 13A and a second sub input shaft 13B. A provided second pulley 22 and an endless belt 23 wound around the first and second pulleys 21 and 22 are provided. The groove widths of the first and second pulleys 21 and 22 are increased or decreased in opposite directions by hydraulic pressure, and the gear ratio between the first auxiliary input shaft 13A and the second auxiliary input shaft 13B can be continuously changed. The first pulley 21 is supported by a first fixed-side pulley half 21A fixed to the first sub-input shaft 13A and a first fixed-side pulley supported by the first sub-input shaft 13A so as not to be relatively rotatable and axially movable. The first movable-side pulley half 21B that approaches / separates from the half 21A. The second pulley 22 is supported by the second fixed-side pulley half 22A fixed to the second sub-input shaft 13B and the second sub-input shaft 13B so as not to be relatively rotatable and axially movable. The second movable-side pulley half 22B approaches and separates from the pulley half 22A.

  Further, the third reduction gear 39 fixed to the second input shaft 13B meshes with the fourth reduction gear 40 fixed to the auxiliary shaft 14, and the fifth reduction gear 29 and the fifth reduction gear 29 supported relatively rotatably on the auxiliary shaft 14 are output. The sixth reduction gear 30 fixed to the shaft 15 meshes, and the final drive gear 31 integral with the sixth reduction gear 30 and the final driven gear 32 provided on the differential gear 33 mesh. A reverse drive gear 34 supported relatively rotatably on the countershaft 14 meshes with a reverse idle gear 35 fixed to the idle shaft 16, and a reverse driven gear 36 fixed to the idle shaft 16 meshes with the sixth reduction gear 30. .

  A first output switching mechanism 37 comprising a dog clutch is provided on the outer periphery of the countershaft 14. The first output switching mechanism 37 can switch between a neutral position, a right movement position, and a left movement position. When the first output switching mechanism 37 moves to the right from the neutral position, the fifth reduction gear 29 is coupled to the countershaft 14, and when it moves left from the neutral position, the reverse drive is performed. A gear 34 is coupled to the countershaft 14. A second output switching mechanism 38 composed of a dog clutch is provided on the outer periphery of the first auxiliary input shaft 13A. The second output switching mechanism 38 can switch between a neutral position and a right movement position. When the second output switching mechanism 38 moves to the right from the neutral position, the sixth reduction gear 30 and the final drive gear 31 are coupled to the first sub input shaft 13A.

  The rotation of the main input shaft 13 is decelerated by the first and second reduction gears 25 and 26 and transmitted to the first sub input shaft 13A. On the other hand, the rotation of the main input shaft 13 is accelerated by the first and second induction gears 27 and 28 and transmitted to the second sub input shaft 13B.

  In the LOW mode of the continuously variable transmission T, the LOW friction clutch 24A is engaged, the HI friction clutch 24B is disengaged, the first output switching mechanism 37 is operated to the right movement position (LOW position), and the second output The switching mechanism 38 is operated to the neutral position.

  As a result, the driving force of the engine E is crankshaft 11 → torque converter 12 → main input shaft 13 → LOW friction clutch 24A → first reduction gear 25 → second reduction gear 26 → first auxiliary input shaft 13A → first pulley 21. → Endless belt 23 → Second pulley 22 → Second auxiliary input shaft 13B → Third reduction gear 39 → Fourth reduction gear 40 → Sub shaft 14 → First output switching mechanism 37 → Fifth reduction gear 29 → Sixth reduction gear 30 → output shaft 15 → final drive gear 31 → final driven gear 32 is transmitted to the differential gear 33 through a path.

  In the LOW mode, the belt type continuously variable transmission mechanism 20 transmits driving force from the first auxiliary input shaft 13A side to the second auxiliary input shaft 13B side, and the overall transmission of the continuously variable transmission T is changed in accordance with the change of the transmission gear ratio. The ratio is changed.

  In the HI mode of the continuously variable transmission T, the LOW friction clutch 24A is disengaged, the HI friction clutch 24B is engaged, the first output switching mechanism 37 is operated to the neutral position, and the second output switching mechanism 38 is moved to the right. It is operated to the moving position (HI position).

  As a result, the driving force of the engine E is: crankshaft 11 → torque converter 12 → main input shaft 13 → first induction gear 27 → second induction gear 28 → HI friction clutch 24B → second auxiliary input shaft 13B → second pulley 22 It is transmitted to the differential gear 33 through the path of the endless belt 23, the first pulley 21, the first auxiliary input shaft 13 A, the second output switching mechanism 38, the output shaft 15, the final drive gear 31, and the final driven gear 32.

  In the HI mode, the belt-type continuously variable transmission mechanism 20 transmits driving force from the second auxiliary input shaft 13B side to the first auxiliary input shaft 13A side, and the overall transmission of the continuously variable transmission T is changed according to the change in the gear ratio. The ratio is changed.

  In the reverse mode of the continuously variable transmission T, the LOW friction clutch 24A is engaged, the HI friction clutch 24B is disengaged, the first output switching mechanism 37 is operated to the left movement position (RVS position), and the second output The switching mechanism 38 is operated to the neutral position.

  As a result, the driving force of the engine E is crankshaft 11 → torque converter 12 → main input shaft 13 → LOW friction clutch 24A → first reduction gear 25 → second reduction gear 26 → first auxiliary input shaft 13A → first pulley 21. → Endless belt 23 → second pulley 22 → second auxiliary input shaft 13B → third reduction gear 39 → fourth reduction gear 40 → sub shaft 14 → first output switching mechanism 37 → reverse drive gear 34 → reverse idle gear 35 → It is transmitted in reverse rotation to the differential gear 33 through the path of the idle shaft 16 → the reverse driven gear 36 → the sixth reduction gear 30 → the output shaft 15 → the final drive gear 31 → the final driven gear 32.

  In the reverse mode, the belt-type continuously variable transmission mechanism 20 transmits driving force from the first auxiliary input shaft 13A side to the second auxiliary input shaft 13B side, and the overall transmission of the continuously variable transmission T is changed according to the change in the transmission gear ratio. The ratio is changed.

  Next, the structure of the first pulley 21 will be described in detail with reference to FIG.

  A ball bearing 42 that rotatably supports the shaft end of the first auxiliary input shaft 13A on the transmission case 41 is provided in an inner race 42a that fits on the outer periphery of the first auxiliary input shaft 13A and a recess 41a of the transmission case 41. An outer race 42b to be fitted and a plurality of balls 42c arranged between the inner race 42a and the outer race 42b. The second reduction gear 26 disposed adjacent to the first movable-side pulley half 21B of the first pulley 21 has a boss portion 26a that is spline-fitted to the outer periphery of the first auxiliary input shaft 13A, and a diameter from the boss portion 26a. A disk-shaped side wall part 26b extending outward in the direction and a plurality of gear teeth 26c formed on the outer periphery of the side wall part 26b.

  The boss portion 26a of the second reduction gear 26, the shim 43, and the inner race 42a of the ball bearing 42 are inserted in this order from the shaft end side of the first sub input shaft 13A, and the middle of the first sub input shaft 13A in the axial direction. The inner race of the boss portion 26a of the second reduction gear 26, the shim 43, and the ball bearing 42 is interposed between the step portion 13Aa formed on the nut and the nut 44 screwed onto the shaft end of the first auxiliary input shaft 13A. 42a is pinched and fastened. The outer race 42b of the ball bearing 42 is held in the recess 41a so as not to drop off by a retainer 46 fixed to the transmission case 41 with a bolt 45.

  The first movable pulley half 21B of the first pulley 21 supported on the outer periphery of the first sub-input shaft 13A so as not to be relatively rotatable and axially movable projects from the radially outer end toward the shaft end side. A cylindrical cylinder 48 is provided, and an outer peripheral portion 49 a extending in the radial direction of an annular piston 49 abuts on the inner peripheral surface of the cylinder 48 via a seal member 50 so as to be slidable in the axial direction.

  A cylindrical protruding portion 26d protrudes from the side wall portion 26b of the second reduction gear 26 toward the first movable pulley half 21B, and an inner peripheral portion 49b extending in the axial direction of the piston 49 on the outer peripheral surface of the protruding portion 26d. The inner peripheral surface is fitted through the seal member 51. The tip of the inner peripheral portion 49 b extending in the axial direction of the piston 49 abuts against the side wall portion 26 b of the second reduction gear 26 in the axial direction.

  Thus, the pulley oil chamber closed by the first movable pulley half 21B, the cylinder 48, the piston 49, and the side wall portion 26b sandwiched between the boss portion 26a and the protruding portion 26d of the second reduction gear 26. 52 is partitioned. The oil passage 13Ab formed inside the first sub input shaft 13A communicates with the pulley oil chamber 52 via the oil hole 13Ac of the first sub input shaft 13A and the oil hole 21Ba of the first movable pulley half 21B. The first movable-side pulley half 21B is biased toward the first fixed-side pulley half 21A by the hydraulic pressure supplied to the pulley oil chamber 52.

  The piston 49 of the present embodiment is made of synthetic resin, and the back surface (the surface opposite to the pulley oil chamber 52) has a plurality of first extending radially outward from the first auxiliary input shaft 13A. Ribs 49c are formed.

  Next, the operation of the embodiment of the present invention having the above configuration will be described.

  When hydraulic pressure is supplied from the oil passage 13Ab and the oil hole 13Ac of the first auxiliary input shaft 13A to the pulley oil chamber 52 via the oil hole 21Ba of the first movable pulley half 21B of the first pulley 21, the first movable pulley half The body 21B and the cylinder 48 are urged away from each other, but the piston 49 is fixed to the first auxiliary input shaft 13A via the second reduction gear 26, so the first movable pulley half 21B Moves on the first auxiliary input shaft 13A toward the first stationary pulley half 21A, and the groove width of the first pulley 21 decreases.

  The second reduction gear 26, the shim 43, and the inner race 42a of the ball bearing 42 are sandwiched between the step portion 13Aa of the first sub-input shaft 13A and the nut 44, and the inner peripheral portion 49b of the piston 49 is connected to the first sub-input shaft 13A. Since it is supported by the protruding portion 26d of the side wall portion 26b of the second reduction gear 26 without being sandwiched between the step portion 13Aa of the input shaft 13A and the nut 44, the thickness of the inner peripheral portion 49b of the piston 49 Not only can the axial dimension of the continuously variable transmission T be shortened, but the number of parts fastened by the nut 44 is reduced, so that the reliability of the nut 44 against loosening is improved.

  In addition, the position of the inner peripheral portion 49b of the piston 49 of the present embodiment is shifted radially outward from the first auxiliary input shaft 13A, and is more radial than the protruding portion 26d in the side wall portion 26b of the second reduction gear 26. Since the inner portion fulfills a part of the function of the piston 49, the size of the piston 49 can be reduced by that amount and the weight can be reduced.

  If the inner peripheral portion 49b of the piston 49 extends radially inward and is sandwiched between the step portion 13Aa of the first auxiliary input shaft 13A and the second reduction gear 26, the oil pressure in the pulley oil chamber 52 acts on the piston 49. There is a possibility that a large bending moment acts in the vicinity of the inner peripheral portion 49b of the piston 49. However, according to the present embodiment, the inner peripheral portion 49b of the piston 49 fitted to the outer peripheral surface of the protruding portion 26d of the second reduction gear 26 extends in the axial direction to the side wall portion 26b of the second reduction gear 26. Since the contact is applied, the load acting on the inner peripheral portion 49b of the piston 49 is mainly an axial force, and the bending moment is reduced, so that a low-strength material can be used for the piston 49 to reduce the cost.

  Further, since the piston 49 is made of synthetic resin, the weight can be further reduced. However, the synthetic resin piston 49 has a problem that the strength is lower than that of a metal one. However, according to the present embodiment, since the plurality of first ribs 49c extending radially in the radial direction are provided on the back surface of the piston 49, the strength of the piston 49 can be increased by the first ribs 49c.

  Further, when the piston 49 is made of a different material with respect to the second reduction gear 26 and the cylinder 48, if the piston 49 is rigidly joined to the projecting portion 26d of the second reduction gear 26 and the cylinder 48, the joint portion is caused by the difference in thermal expansion coefficient. May cause damage due to excessive stress.

  In order to absorb the difference in coefficient of thermal expansion due to different materials, the dimensional relationship between the piston 49 and the protruding portion 26d of the second reduction gear 26 and the cylinder 48 is a fitting relationship having an appropriate clearance when warm. Since the hydraulic pressure pressing the piston 49 against the second reduction gear 26 always acts when the engine E is driven, the piston 49 does not come out of the second reduction gear 26.

  In addition, the piston 49 is sealed with a seal member 51 at a contact surface of the second reduction gear 26 with respect to the protruding portion 26d. By adopting such a structure, it is not necessary to integrate the piston 49 and the second reduction gear 26 by welding, and the gear tooth profile of the second reduction gear 26 is kept in a good state by avoiding a decrease in accuracy due to welding distortion. be able to. Moreover, even if the piston 49 is made of a material having a different coefficient of thermal expansion, an excessive thermal stress is not generated in the fitting portion, so that the thickness can be reduced.

  Next, a second embodiment of the present invention will be described with reference to FIG.

Second embodiment

  The piston 49 according to the first embodiment includes a plurality of first ribs 49c that extend radially outwardly about the first auxiliary input shaft 13A on the back surface, but the piston 49 according to the second embodiment. Are provided with four annular second ribs 49d extending in the circumferential direction so as to connect the plurality of first ribs 49c to each other.

  According to the second embodiment, the rigidity of the piston 49 can be further increased by the cooperation of the first ribs 49c and the second ribs 49d orthogonal to each other.

  Further, since the piston 49 is made of synthetic resin, the degree of freedom of the shape is increased, and it is easy to set the shape of the piston 49 to a shape in which stress concentration is less likely to occur compared to the first embodiment. In addition, since it is easy to reduce the volume of the pulley oil chamber 52 by increasing the size of the piston 49, the required oil amount can be reduced and the entire continuously variable transmission T can be reduced in weight.

  The embodiments of the present invention have been described above, but various design changes can be made without departing from the scope of the present invention.

  For example, although the present invention is applied to the first pulley 21 in the embodiment, the present invention may be applied to the second pulley 22.

  The framework of the transmission to which the pulley of the present invention is applied is not limited to the continuously variable transmission T of the embodiment.

  Further, the bearing of the present invention is not limited to the ball bearing 42 of the embodiment, and may be another type of bearing such as a roller bearing.

  The number of the second ribs 49d is not limited to the four in the embodiment.

Claims (4)

A pulley (21), which is arranged on a rotating shaft (13A) supported by a transmission case (41) via a bearing (42) and on which an endless belt (23) is wound, is fixed to the rotating shaft (13A). A stationary pulley half (21A), and a movable pulley half (21B) supported so as to be relatively non-rotatable and axially movable at a cylindrical inner peripheral support portion with respect to the rotating shaft (13A). A cylindrical cylinder (48) protruding in the axial direction from the back surface of the movable pulley half (21B) and an outer peripheral portion (49a) supported by the rotational shaft (13A) so as not to be axially movable. An annular piston (49) slidably fitted to the inner peripheral surface of the cylinder (48), and a pulley oil chamber (52) defined between the cylinder (48) and the piston (49). A transmission pulley comprising:
A gear (26) is provided on the rotating shaft (13A), and the gear (26) includes a boss portion (26a) and a disk-shaped side wall portion (26b) extending radially outward from the boss portion (26a). And a projecting portion (26d) projecting in the axial direction from the side wall portion (26b) toward the cylinder (48), and the side wall portion (26b) is in the cylinder (48) with respect to the boss portion (26a). ) Is axially offset toward
A boss portion (26a) of the gear (26) is sandwiched between a step portion (13Aa) formed on the rotating shaft (13A) and an inner race (42a) of the bearing (42),
The inner race (42a) and the boss portion (26a) are fastened between a nut (44) screwed to the rotating shaft (13A) and the step portion (13Aa),
By fitting the inner peripheral portion (49b) of the piston (49) to the outer peripheral surface of the protruding portion (26d) and hitting the side wall portion (26b), the protruding portion (26d) in the radial direction is A transmission pulley characterized by being arranged between an inner peripheral portion (49b) of a piston (49) and an inner peripheral side support portion of the movable pulley half (21B).   The transmission pulley according to claim 1, wherein the piston is made of a synthetic resin.   The transmission pulley according to claim 1 or 2, wherein a plurality of first ribs (49c) extending radially in a radial direction are provided on the back surface of the piston (49).   The annular second rib (49d) extending in the circumferential direction on the back surface of the piston (49) and connecting the plurality of first ribs (49c) to each other is projected. Pulley for transmission.

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