JP2548258B2 - Belt type continuously variable transmission - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a belt type continuously variable transmission, and particularly to a V belt type continuously variable transmission suitable for use in an automatic continuously variable transmission mounted on an automobile. The present invention relates to a device, and more particularly, to a mechanism for adjusting the belt initial tension after assembling a pulley and a belt.

(B) Conventional technology Generally, this type of V-belt continuously variable transmission (CVT)
Primary and secondary pulleys each including a movable sheave and a fixed sheave are provided, and these pulleys are wound around a metal belt, and the movable sheave is moved by a hydraulic piston to perform a speed change operation as appropriate.

Therefore, the continuously variable transmission requires an oil pump and a hydraulic circuit because of the use of hydraulic pressure, has a very complicated structure, is a large-sized device, and exerts excessive belt clamping pressure to transmit the transmission. This is disadvantageous in terms of efficiency and belt durability, and further, if the hydraulic pressure drops for any reason, transmission becomes impossible due to insufficient belt clamping pressure.

Therefore, as shown in FIG. 5, by the applicant, the metal belt 33 is wound around the primary pulley 31 and the second pulley 32, and the movable sheaves 31b and 32b of both pulleys 31 and 32 are attached to the ball screw devices 35 'and 36'. The belt-type continuously variable transmission 30 ′ is provided with a pressure adjusting cam mechanism 34 that moves axially by the fixed sheave 31 a and applies an axial force corresponding to the transmission torque to the fixed sheave 31 a.
Has been proposed (see JP-A-62-13853).

Then, the ball screw device 3 on the primal pulley side
In 5 ', a bolt portion 35'a is fitted to the retainer 4'via a ball spline A, and one end of the bolt portion 35'a is connected to the movable sheave 31b via a thrust bearing 3'b. Further, a nut portion 35'b, which is integral with the gear portion 35'c, is screwed into the bolt portion 35'a, and the rotation of the nut portion 35'b causes the bolt portion 35'a to swing in the axial direction, whereby the movable sheave 31b. The belt clamping pressure is applied by pressing. Here retainer 4 '
One end of the bolt is connected to the stepped portion 15b of the case 15 by a spline B so as to be movable in the axial direction so as to prevent rotation of the bolt portion 35'a. On the other hand, the ball screw device 36 'on the second pulley side has the same structure.

(C) Problems to be Solved by the Invention Therefore, the ball screw device 3 of the continuously variable transmission 30 'described above is
The 5'and 36 'have no means for adjusting the initial tension to the belt 33 after assembly. Therefore, if there is play or dimensional error in the axial direction of the shaft, bearing, bolts, and nuts, the belt 33 will be loosened or pulled more than necessary. The slack of the belt 33 causes backlash of the pressure adjusting cam mechanism, and excessive tension causes deterioration of transmission efficiency and shortening of belt and bearing life. Further, the initial position of the belt 33 is displaced, which causes misalignment of the belt 33, deterioration of transmission efficiency, and shortening of belt life.

Therefore, the present invention is provided with a belt tension adjusting mechanism that can be operated after assembling the constituent parts of the continuously variable transmission, and thereby applies proper initial tension to the belt against rattling and dimensional error of the parts. It is an object of the present invention to provide a belt-type continuously variable transmission that solves the above-mentioned problems by making the above adjustments.

(D) Means for Solving Problems The present invention has been made in view of the above circumstances, and, for example, as shown with reference to FIG.
b), supported by (30a) and capable of relative movement in the axial direction 2
Primary pulley and second pulley (31), (32) consisting of individual sheaves (31a), (31b), (32a), (32b)
And a pressure adjusting mechanism (34) for applying an axial force corresponding to the transmission torque to at least one of the pulleys (31) and (32).
A belt (33) wound around the pulleys (31) and (32), and bolts (35a) and (36a) provided on the back surfaces of the movable sheaves of the pulleys. There is a nut part (35b) (36b) that fits, and either one of these bolt parts and nut part (35b, 36b) is mutually rotated in the rotational direction via the gear part (35c, 36c, 102, 103, 101). The primary side and secondary side screw devices (35a, 36a) which are connected and the other side (35a, 36a) are connected to the fixing member (15) and which move in the movable sheave axial direction of both pulleys based on the relative rotation of the bolt part and the nut part. (36) and a speed change operation device (100) that is connected to the gear part and applies the relative rotation to the bolt part and the nut part of the screw device, the belt type continuously variable transmission (30) , The bolt portion in at least one of the both screw devices, and Tsu DOO portion of the other (35a), a fixed member (1 (36a)
5) and adjustment retainers (4), (8), which are rotatably arranged while being restricted from moving in the axial direction with respect to the fixed member, and are integrally connected to the other in the rotational direction, Holding means (4d) (7) for holding the adjustment retainer at an appropriate rotational position, and changing one axial relative position with respect to the other of the bolt portion and the nut portion based on the rotation of the adjustment retainer. And an adjusting mechanism (39) for adjusting the initial tension of the belt.

(E) Operation With the above configuration, the adjusting retainers (4) and (8) are appropriately rotated in a state where the respective components of the belt type continuously variable transmission (30) are incorporated in the case (15). Then, the other of the bolt portion and the nut portion integrated with the retainer, for example, the bolt portions (35a) and (36a) rotates, and the retainer is restricted from moving in the axial direction with respect to the fixing member (15). Based on the rotation of the other, one of the nuts (35b), (3
6b) moves in the axial direction to properly adjust the initial tension of the belt 32. Then, the adjusting retainer is held by the holding means (4d) (7) at an appropriate position where the adjusting retainer is appropriately rotated, and the belt tension is held in an appropriate state.

In this state, by rotating the gear shift operating device (100), one of the bolt parts and the nut parts of the screw devices (35), (36), for example, the nut parts (35b), (36) via the gear part.
b) is rotated, both screw devices expand and contract in the axial direction,
The effective diameter of both pulleys (31) and (32) is adjusted to control the gear ratio of the belt type continuously variable transmission.

Specifically, for example, the second pulley side screw device (36)
Bolt part (36a), nut part (36b), gear part (36
c), thrust bearings (3c), (3d), and retainer (8) of the belt tension / position adjustment mechanism (39), etc., and then hold the pulley (32) so that the gap is at an appropriate position. The teeth (7a) of the toothed ring (7) and the teeth (8c) of the retainer (8) that form the means are fitted and fixed to the fixing member (15). At the same time, the bolt part (35a), the nut part (35b), the gear part (35c) of the screw device (35) on the primer pulley side,
Thrust bearings (3a), (3b), and belt tension,
The retainer (8) of the position adjusting mechanism (39) and the like are assembled, the belt (33) is wound around these pulley assemblies, and is assembled to the fixing member (15), and a holding means such as a worm is installed. When the adjusting retainer (4) is appropriately rotated by operating the holding means (4d), the bolt portion (35a) rotates integrally with the retainer (4), and the nut portion (35b) with respect to the bolt portion (35a). ) Moves in the axial direction, and the initial tension of the belt (33) and the axial position of the pulley (31) associated with the spacing between the pulleys (31) are properly adjusted.

The reference numerals in the parentheses are for referring to FIG. 1 and do not limit the configuration at all.

(F) Embodiment First, an outline of an automatic continuously variable transmission to which the present invention can be applied will be described. As shown in FIG. 2, the automatic continuously variable transmission 12 includes a single planetary gear device 20 and a belt type gearbox. The continuously variable transmission 30, the transfer device 80, the input shaft 60, and the output member including the reduction gear device 71 and the differential gear device 72.
70, a fluid coupling 13 having a lock-up clutch CL and a forward / reverse switching transmission 90 comprising a dual planetary gear device. In the single planetary gear device 20, the element 20S (or 20R) serving as a reaction force supporting member when the single planetary gear device 20 is used as a reduction mechanism is provided with the transfer device 80.
And can be connected to and disconnected from the input shaft 60 via the high clutch C2.

Specifically, the ring gear 20R of the planetary gear unit 20.
Interlocks with the secondary shaft 30a of the continuously variable transmission 30,
Further, the carrier 20C is interlocked with the output member 70, and the sun gear 20S is interlocked with the low one-way clutch F and the low coast & reverse brake B1 which constitute the locking means via the transfer device 80 and the high clutch C2. .

Further, in the dual planetary gear device 90, the sun gear 90S is connected to the input shaft 60, the carrier 90C is connected to the primary shaft 30b of the continuously variable transmission device 30 and the input shaft 60 is connected via the forward clutch C1. Ring gear 90R is connected to reverse brake B2.

Based on the above configuration, the clutch, brake and one-way clutch in the automatic continuously variable transmission 12 operate as shown in FIG. 3 at each position. It should be noted that * indicates that the lockup clutch CL can be operated appropriately.

More specifically, on the low speed side L in the D range, the low one-way clutch F is operated in addition to the connection of the forward clutch C1. In this state, the rotation of the engine crankshaft causes the lockup clutch CL or the fluid coupling 13 to rotate.
Is transmitted to the input shaft 60 via the input shaft 60, is transmitted directly to the sun gear 90S of the dual planetary gear device 90, and is transmitted to the carrier 90C via the forward clutch C1.
Therefore, the dual planetary gear device 90 rotates integrally with the input shaft 60, transmits the positive rotation to the primary shaft 30b of the belt type continuously variable transmission 30, and further the rotation that is appropriately changed by the continuously variable transmission 30. It is transmitted from the secondary shaft 30a to the ring gear 20R of the single planetary gear device 20. On the other hand, in this state, the sun gear 20S, which is a reaction force supporting element that receives a reaction force, is stopped by the low one-way clutch F via the transfer device 80, and therefore the rotation of the ring gear 20R is taken out from the carrier 20C as decelerated rotation. Further, it is transmitted to the axle shaft 73 via the reduction gear device 71 and the differential gear device 72.

On the high-speed side H in the D range, the high clutch C2 is connected in addition to the forward clutch C1. In this state, the forward rotation, which has been appropriately shifted by the continuously variable transmission device 30 as described above, is taken out from the output portion 30a and input to the ring gear 20R of the single planetary gear device 20. On the other hand, at the same time, the rotation of the input shaft 60 is transmitted to the sun gear 20S by the single planetary gear device 20 via the high clutch C2 and the transfer device 80, whereby the torque of the ring gear 20R and the sun gear 20S is synthesized by the planetary gear device 20. Is output from the carrier 20C. At this time, since rotation against the reaction force is transmitted to the sun gear 20S via the transfer device 80, a predetermined positive torque is transmitted via the transfer device 80 without causing torque circulation. Then, the combined torque from the carrier 20C is transmitted to the axle shaft 73 via the reduction gear device 71 and the differential gear device 72.

In the operation in the D range, the reverse torque is applied (when the engine is braked) based on the one-way clutch F (when the engine is braked). However, in the S range, the low cost & reverse brake B1 operates in addition to the low one-way clutch F, and Power is transmitted even when torque is applied.

In the R range, the reverse brake B2 operates together with the low cost & reverse brake B1. In this state, the rotation of the input shaft 60 is controlled by the dual planetary gear system.
When the ring gear 90R is fixed at 90, it is input from the carrier 90C to the belt type continuously variable transmission 30 as a reverse rotation. On the other hand, the sun gear 20S of the single planetary gear unit 20 is operated based on the operation of the low cost & reverse brake B1.
Therefore, the reverse rotation from the continuously variable transmission 30 is decelerated by the planetary gear unit 20 and taken out to the output member 70.

Further, in the P range and the N range, the low cost & reverse brake B1 operates.

Next, an embodiment of the above-described automatic continuously variable transmission will be described with reference to FIG.

The automatic continuously variable transmission 12 has a transmission case 15 that is divided into three parts, and the input shaft 60 and the primary shaft 30b of the continuously variable transmission 30 are coaxially and rotatably supported by the case 15 so as to be rotatable. In addition to constituting one shaft, the secondary shaft 30a and the gear shaft 70a of the continuously variable transmission 30 are rotatably supported coaxially to constitute a second shaft. Further, on the first shaft, a fluid coupling 13 having a lockup clutch CL, a forward clutch C1, a high clutch C2, a low cost & reverse brake B1, a reverse brake B2, a control unit 40 including a low one-way clutch F, and a forward / reverse switching. A dual planetary gear device 90 and a hydraulic pump 17 that configure the device are provided, and a single planetary gear device 20 is provided on the second shaft.

Explaining the control unit 40 and the input portion further, the input side 60 has the lockup clutch CL and the output member of the fluid coupling 13 engaged at one end thereof, and the sun gear 90S of the dual planetary gear device 90 engaged at the other end thereof. Further, a sleeve portion 15a fixed to the case 15 is disposed on the input shaft 60. Also, the sleeve portion 15a
, A sprocket 81 is connected via a one-way clutch F, and a sleeve shaft 41 connected to the input shaft 60 is rotatably supported. Further, the sleeve shaft
A forward clutch C1 is arranged with its hydraulic actuator 42 on one side of the flange 41a rising from 41, and a high clutch C2 is installed with its hydraulic actuator 43 on the other side. The driven side of the high clutch C2 is connected to a boss of the sprocket 81, and the boss is connected to a low coast and reverse brake B1 disposed in the case 15 together with the hydraulic actuator 45. On the other hand, the forward clutch C1
The driven side of is the carrier 90 of the dual planetary gear unit 90.
C and dual planetary gear unit 90
Ring gear 90R of Case 1 with hydraulic actuator 46
It engages with the reverse brake B2 arranged at 5 (see FIG. 2). The carrier 90C meshes with the pinion 90P1 and the ring gear 90R meshing with each other and with the sun gear 90S.
It supports the pinion 90P2 meshing with.

The single planetary gear device 20 is disposed on a gear shaft (output shaft) 70a constituting a second shaft, and its ring gear 20R is formed integrally with a primary shaft 30a of a belt-type continuously variable transmission 30 described later. Flange part q
It is connected to. A sprocket 82 is rotatably supported on the gear shaft 70a integrally with the sun gear 20S, and a carrier 20C rotatably supporting the pinion 20P is spline-coupled to the gear shaft 70a.

On the other hand, a silent chain 83 is wound around a sprocket 82 integral with the sun gear 20S on the second shaft and a sprocket 81 supported by the low one-way clutch F. The transfer device 80 is configured.

The gear shaft 70a integrally forms a gear 71a to form an output member 70, and the gear 71a is engaged with a gear 71c fixed to an intermediate shaft 71b. Further, a small gear 71d is formed on the intermediate shaft 71b, and the gear 71d meshes with a ring gear 72a fixed to the differential gear device 72,
It constitutes the speed reducer 71. In addition, left and right front axle shafts 73l, 73r extend from the differential gear device 72.

Further, the belt-type continuously variable transmission 30 according to the present invention
As shown in detail in the drawing, it is composed of a primary pulley 31, a secondary pulley 32, and a belt 33 wound around these pulleys, and both pulleys are composed of fixed sheaves 31a, 32a and movable sheaves 31b, 32b, respectively.

The fixed sheave 31a of the primary pulley 31 has a long boss b that is fitted on the primary shaft 30b and extends toward the movable sheave 31b, and the cylindrical hub 2 is integrally formed on the back surface of the flange d. I have. The outer peripheral surface of the hub portion 2 is rotatably supported by the case 15 via the roller bearing 1, and the pressure adjusting cam mechanism 34 is disposed on the inner diameter side of the hub portion 2. The pressure adjusting cam mechanism 34 is composed of a fixed race 34a having a wavy end surface, a movable race 34c, and a roller 34b held between both end surfaces.
4a is screwed to the tip of the primary shaft 30b and is fixed by retaining with a snap ring or the like. The movable race 34c is connected to the spline 2a formed on the inner peripheral surface of the hub 2 so as to be movable only in the axial direction. ing. A predetermined distance c is formed between the fixed race 34a and the inner peripheral surface of the hub portion 2, and the movable case 34c and the primary shaft 30b are also provided.
A predetermined distance c is also formed between the fixed race 34 and the fixed race 34.
Torque is not transmitted by frictional contact between a, the fixed sheave 31a, the movable race 34c, and the shaft 30b. The fixed race 34a has a spline formed on the outer peripheral surface thereof, and serves as an input member, that is, a carrier of the dual planetary gear 90.
90C is connected, and movable race 34c is splined.
While transmitting torque to the fixed sheave 31a via 2a,
An axial force S proportional to the transmission torque is applied through a large number of disc springs 38 that are housed in the recess and that apply a preload.

On the other hand, the primary shaft 30b is formed with an oil hole g which extends through the center thereof and whose tip is closed by a cap f, and a large number of lateral holes for distributing the lubricating oil to necessary portions. Further, the base end thereof, that is, the side end of the dual planetary gear device 90 is an inlay portion h for fitting with the input shaft 60, the outer peripheral surface of the base end portion is a screw portion i, and the fixed sheave 31a. The portion that fits into the boss portion b of is an oil groove j. The tip end of the shaft 30b, that is, the side away from the gear device 90, has a large diameter and a large-diameter flange portion k is integrally formed, and the outer peripheral side inner peripheral surface of the flange portion is used for the thrust bearing 3a. It forms the retainer surface. On the other hand, a cap 15a is fixed to the case 15 by a bolt B so as to cover the large-diameter flange portion k, and the belt tension and the adjustment retainer 4 of the position adjusting mechanism 39 are applied to the stepped portion 15b of the case 15. Closely supported.

The adjusting retainer 4 is composed of an annular member having a U-shaped cross section, and the inner diameter flange portion 4a rotatably supports the tip of the fixed sheave 31a via the radial roller bearing 5a on the inner peripheral surface thereof.
Further, a spline m is formed on the outer peripheral surface thereof, and further, the thrust bearing 3a is held by the outer wall of the side wall portion 4b. Further, the outer flange portion 4e of the retainer 4 is the stepped portion 15b.
A worm wheel 4c is formed on the outer diameter flange 4e of the worm wheel 4c. A worm 4d meshes with the worm wheel 4c, and by rotating the worm 4d, the adjusting retainer 4 is rotated to a fixed position in the axial direction in contact with the bearing 3a, and is further held at a predetermined rotation position.

On the other hand, the movable sheave 31b has a boss n that is a fixed sheave 31a.
The ball screw device 35 is disposed at the back of the flange portion o while being slidably supported by the boss portion b via a ball spline 6a. The ball screw device 35 includes a bolt portion 35a and a nut portion 35b. The bolt portion 35a has a screw formed on one side of the inner diameter surface thereof so as to be screwed into the spline m of the adjusting retainer 4, and the nut portion 35b has an outer peripheral surface thereof. A circular gear portion 35c having a spline e formed on its outer peripheral portion and a circular gear formed spirally on the outer peripheral portion is spline-coupled, and the thrust bearing 3b is provided between the gear portion 35c and the flange portion o of the movable sheave 31b. Is intervening. Therefore, the bolt portion 35a of the ball screw device 35 is non-rotatably connected to the case 15 via the adjusting retainer 4 and axially immovable to the primary shaft 30b via the thrust bearing 3a, and its nut portion 35b is movable. It is connected to the sheave 31b via a thrust bearing 3b so as to move integrally in the axial direction.

On the other hand, the second pulley 32 has a fixed sheave 32a and a movable sheave 32a, the fixed sheave 32a is rotatably supported by the case 15 by the roller bearing 5b, and is non-rotatable via the key 6c on the secondary shaft 30b. The movable sheave 32b is connected to the secondary shaft 30a via the ball spline 6b so as to be slidable.

The secondary shaft 30a has a relatively large-diameter oil hole g ', which extends through the center of the secondary shaft 30a and is closed at its tip by a cap f', and supplies lubricating oil to a necessary portion. A large number of lateral holes are formed, and further, the base end side thereof, that is, the single planetary gear device 20 side is expanded to form a large-diameter flange portion q, and the flange portion q
The diameter of the oil hole g 'corresponding to the diameter becomes large in a stepped manner, and the output shaft 70a is fitted to this portion via the needle bearing 5c. The shaft 30a has a ball groove r, a key groove s, and a screw t formed at its tip in order from a large diameter flange portion q on its outer peripheral surface, and supports a movable sheave 32b and a fixed sheave 32a, respectively. 9 is screwed and retained.

Further, a fixing toothed ring 7 is fixed by a bolt B in substantially the same plane as the bearing 5c in the case 15, and a large number of teeth 7a are formed on the inner peripheral surface of the ring 7. Further, a belt tension / adjustment retainer 8 of a position adjusting mechanism 39 is supported in contact with a stepped portion 15c formed in the case 15, and the retainer 8 is made of an annular member having a U-shaped cross section and has an inner diameter flange. The part 8a has a roller bearing on its inner peripheral surface.
The secondary shaft 30a is rotatably supported via 5d, and a spline u is formed on the outer peripheral surface thereof.
Further, the thrust bearing 3c is held between the outer peripheral wall of the side wall portion 8b and the large-diameter flange portion q. And step 15
A tooth 8c capable of selectively meshing with the tooth 7a of the ring 7 is formed on the outer diameter flange portion 8d protruding outside c, and the retainer 8 is held by the ring 7 at a predetermined rotation position of the retainer 8.

Further, a ball screw device 36 is disposed on the back surface of the flange y of the movable sheave 32b, and the ball screw device 36 includes a bolt portion 36a and a nut portion 36b. The bolt portion 36a is formed with a screw on one side of the inner peripheral surface for screwing with the spline u of the adjusting retainer 8, and the nut portion 36b is formed with a spline x on the outer peripheral surface thereof and spirally formed on the outer peripheral portion. The non-circular gear portion 36c in which the non-circular gear is formed is spline-coupled, and the thrust bearing 3d is interposed between the gear portion 36c and the flange portion y. Therefore, the bolt portion 36a of the ball screw device 36 is non-rotatably connected to the case 15 via the fixing ring 7 and the adjusting retainer 8 and is axially immovable to the large-diameter flange portion q of the primary shaft 30a via the thrust bearing 3c. In addition, the nut portion 36b of the movable sheave 3 via the thrust bearing 3d.
It is connected so as to move integrally with 2b in the axial direction.

Then, the primary pulley 31 and the secondary pulley 32
As shown in FIG. 4, a speed change device 100 that adjusts the interval between the two sheaves is disposed in a triangular shape between the two pulleys 31 and 32. It has an operation shaft 101 that is freely supported. Since FIG. 4 is an exploded view, the operation shaft 101 is drawn upward, but actually, the operation shaft 101 is located at an intermediate portion between the primary shaft 30b and the secondary shaft 30a in a front view. A circular gear 102 and a non-circular gear 103 are fixed to the operation shaft 101, and the circular gear 102 is a circular gear 35c fixed to a nut portion 35b on the primary pulley 31 side.
The non-circular gear 103 meshes with the non-circular gear 36c fixed to the nut portion 36b on the secondary pulley 32 side. Further, on the opposite side of the circular gear 35c, the circular gear 102 is meshed with a small diameter gear 105a formed of a spur gear or a helical gear provided on the intermediate shaft 105, and the intermediate shaft 105 is formed with a different intermediate shaft 106. Small diameter gear 106a
It is fixed from a large-diameter gear 105b that meshes with, and these gears constitute a reduction gear transmission 107 with high transmission efficiency. A relatively small electric motor (or ultrasonic motor) 109 is installed on the case 15 so as to project to one side, and the output shaft 109a of the motor 109 is provided with a large-diameter gear 106b provided on the intermediate shaft 106. Shaft 110 having small diameter gear 110a that meshes with
Is fixed to the shaft 110, and the brake plate 111a is attached to the shaft 110.
Has been fixed. An electromagnetic coil member 111b is fixed to the case 15 with bolts.
Also, an electromagnetic brake 111 that holds the operation shaft 101 in a stopped state by the brake plate 111a is configured. When an ultrasonic motor is used, a special holding mechanism such as the above-mentioned electromagnetic brake is not required since the motor has a holding mechanism.

Next, assembly of the belt type continuously variable transmission 30 will be described.

On the primary side, the thrust bearing 3a is first installed in the primary shaft 30b from the screw i side, and then the movable sheave 31b and the thrust bearing 3a are attached to the fixed sheave 31a.
b, the assembly incorporating the ball screw device 35 and the adjusting retainer 4 is incorporated into the shaft 30b, and the disc spring 38, the movable race 34c and the roller 34b are fitted into the hub 2;
The fixed race 34a is screwed into the screw i to prevent and fix it, thereby completing the assembly. On the other hand, on the secondary side, the thrust bearing 3c, the adjusting retainer 8, the ball screw device 36, and the movable sheave are sequentially attached to the secondary shaft 30a from the screw t side.
32b and the fixed sheave 32a are assembled, and the nut part 9 is tightened to the screw t of the shaft 30a, and the assembly is completed.

Then, the primary-side sub-assembly assembled above is a state in which the belt 33 is disposed between the sheaves 31a and 31b,
The fixed sheave hub 2 is inserted into the roller bearing 1, and the adjusting retainer 4 is inserted into the step 15 b of the case 15, and is assembled to the split case 15. Further, the secondary side sub-assembly is assembled into the split case 15 by inserting the adjusting retainer 8 into the step portion 15c of the case 15 and the boss portion of the movable sheave 32a into the roller bearing 5b.

In this state, the initial tension of the belt is not accurate due to the dimensional tolerance of each member, and the stroke at the time of reversing the transmission torque of the pressure adjusting cam mechanism 34 is large. Therefore, the secondary side appropriately rotates the adjusting retainer 8. Then, the bolt portion 36a integrated with the retainer 8 is relatively rotated with respect to the nut portion 36b, the gap between the pulleys 32 is properly adjusted, and in this state, the teeth 7a of the fixing ring 7 become the teeth 8c of the retainer 8. Fit and fix the ring 7 with the bolt B. On the other hand, the primary side
Rotate the worm 4d to rotate the adjusting retainer 4. Then, the bolt portion 35a rotates integrally with the retainer 4, and the bolt portion 35a is axially positioned by the thrust bearing 3a. Therefore, the nut portion 35b moves in the axial direction to move the gap between the pulleys 31. Adjust properly. As a result, the initial tension of the belt is adjusted so that the stroke of the pressure adjusting cam mechanism 34 becomes appropriate, and the axial position of both pulleys 31, 32, that is, the belt running line is adjusted appropriately.

If the worm 4d is operated from the outside of the case 15, it is possible to make adjustments with the case assembled.
Further, a worm may be installed on the secondary side, or a worm may be installed on both the primary and secondary sides, and the primary may be provided with an adjustment retainer only on one of the secondary sides.

 Next, the operation of this embodiment will be described.

The rotation of the engine crankshaft is the lockup clutch CL
Alternatively, the power is transmitted to the input shaft 60 via the fluid coupling 13 and further transmitted to the sun gear 90S of the dual planetary gear device 90 and also transmitted to the sleeve shaft 41. In the D range and the S range, since the forward clutch C1 is connected and the reverse brake B2 is released, the dual planetary gear device 90 rotates with the sun gear 90S and the carrier 90C integrally, and the forward rotation starts from the carrier 90C. The power is transmitted to the fixed race 34a of the pressure adjusting cam mechanism 34 in the belt-type continuously variable transmission 30.

The rotation of the fixed race 34a rotates the primary shaft 30b that is screwed together i, and also rotates the fixed sheave 31a of the primary pulley 31 via the roller 34b and the movable race 34c located on the wavy end face and the spline 2a. The movable sheave 1b via the ball spline 6a.
To rotate. At this time, the fixed sheave 31a is supported by the case 15 at both ends thereof via the bearings 1 and 5a, and has a space between the fixed race 34a and the fixed sheave hub 2 and between the movable race 34c and the primary pulley 30b. Since it has c, torque is not transmitted from the fixed race 34a and the primary shaft 30b to the fixed sheave 31a via friction, and the entire amount of torque transmitted from the carrier (input member) 90C is transmitted via the pressure adjusting cam mechanism 34. Transmitted to the fixed sheave 31a. Then, in the pressure adjusting cam mechanism 34, an axial force corresponding to the input torque acting on the fixed race 34a acts on the back surface of the sheave 31a via the disc spring 38, while the other sheave 31b corresponds to a predetermined gear ratio. Since the ball screw device 35 is fixed in its length direction, an equivalent reaction force acts on the rear surface of the sheave 31b via the thrust bearing 3b, which causes the primary pulley 31 to have a holding force corresponding to the input torque. Hold the belt 33. The axial force S acting on the movable sheave 31b acts on the large-diameter flange portion k of the primary shaft b via the thrust bearing 3b, the ball screw device 35, the adjusting retainer 4 and the thrust bearing 3a,
On the other hand, the axial force S acting on the fixed sheave 31a acts on the shaft 30b from the fixed race 34a via the screw i, and is thus carried in the shaft 30b as a tensile force of the shaft 30b. Further, the rotation of the belt 33 is transmitted to the secondary pulley 32,
Further, it is transmitted to the secondary shaft 30a via the key 6c and the ball spline 6b.

In transmitting the belt, the motor 109 is controlled based on signals from sensors such as the throttle opening and the vehicle speed, and the operation shaft 101 is rotated via the reduction gear 107.
Then, the primary pulley via the circular gears 102 and 35c
The nut portion 35b of the 31-side ball screw device 35 rotates, and the nut portion 36b of the second pulley 32-side ball screw device 36 rotates via the non-circular gears 103 and 36c. As a result, the nut portions 35b and 36b rotate relative to the bolt portions 35a and 36a, which are stopped by the case 15 by the adjustment retainers 4 and 8, and the ball screw devices 35 and 36 rotate the thrust bearings 3b and 3d.
The movable sheaves 31b and 32b are moved via the to set the primary pulley 31 and the second pulley 32 to a predetermined effective diameter, and a set torque ratio is obtained. When the set torque ratio is reached, the motor 109 is de-energized and the electromagnetic brake 111 is actuated to hold the pulleys 31 and 32 in the torque ratio state. At this time, since both ball screw devices move linearly, there is a difference between the original movement amount of the movable sheave defined by the belt 33, but the secondary pulley 32 rotates through the non-circular gears 103 and 36c. The movable sheave is moved by an amount that matches the original movement amount. Also,
On the primary pulley 31 side, the belt clamping pressure by both pulleys 31a, 31b and 32a, 32b does not act on the case 15 by pulling the primary shaft 30b via the thrust bearing, and similarly the secondary pulley
Also on the 32 side, it does not act on the case 15 by pulling the secant shaft 30a.

Further, the secondary shaft of the belt type continuously variable transmission 30
The rotation of 30a is transmitted to the ring gear 20R of the single planetary gear unit 20, and further via the carrier 20C to the gear shaft 70a.
Is transmitted to

In the low range L in the D range, the low one-way clutch F is in the operating state as shown in FIG. 3, and therefore the sun gear 20S receives a reaction force when the torque is transmitted from the ring gear 20R to the carrier 20C. The sun gear 20S is prevented from rotating by the low one-way clutch F via the transfer device 80, and the single planetary gear device 20 constitutes a reduction mechanism. Therefore, the rotation of the secondary shaft 30a of the belt type continuously variable transmission 30 is
The single planetary gear device 20 simply reduces the speed, and further the gears 71a and 71c, the intermediate shaft 71b, the gear 71d, and the mount gear 72a.
Is further reduced through a reduction gear device 71 consisting of the left and right front axle shafts 72l, 72 through a differential gear device 72.
transmitted to r.

Also, when the throttle opening and vehicle speed reach a predetermined value,
The high clutch C2 is connected by a signal from the control unit and is switched to the high speed side. Then, the rotation of the input shaft 60 is transmitted to the belt-type continuously variable transmission 30 and the sleeve shaft
It is transmitted to the sprocket 81 via 41 and the high clutch C2, and further transmitted to the sun gear 20S of the single planetary gear unit 20 via the silent chain 83 and the sprocket 82. At this time, since the sprocket 81 on the input side of the transfer device 80 receives the reaction force from the sun gear 20S of the single planetary gear device by the low one-way clutch F, the shift shock due to the grip change is prevented, and the high clutch C2 is prevented. When connected, it starts rotating smoothly and transmits torque to the sun gear 20S. As a result, the torque continuously changed by the belt type continuously variable transmission 30, the torque through the transfer device 80, and the single planetary gear device 20 are combined, and the combined torque is generated by the carrier 20C.
Is transmitted to the gear shaft 70a. Further, similarly to the low-speed side, the power is transmitted to the left and right front axle shafts 72l and 72r via the reduction gear device 71 and the differential gear device 72.

Further, on the low speed side L in the S range, negative torque due to engine braking or the like is also received, so that the low cost & reverse brake B1 is engaged and the sprocket 81 is prevented from both forward and reverse rotation. The high-speed side H in the S range is D
Similar to the high speed side of the range.

On the other hand, in the R range, the forward clutch C1 is released and the reverse brake B2 is engaged. Accordingly, the rotation of the input shaft 60 transmitted to the sun gear 90S of the dual planetary gear device 90 is transmitted to the primary shaft 30b of the belt-type continuously variable transmission 30 as reverse rotation from the carrier 90C with the stop of the ring gear 90R. At this time, the reaction torque from the sun gear 20S of the single planetary gear device 20 acts on the sprocket 81 as a reverse rotation via the transfer device 80, so that the low cost & reverse brake is applied.
B1 operates to stop the sprocket 81.

(G) Effect of the Invention As described above, according to the present invention, with the belt type continuously variable transmission mounted, the adjustment retainer (4),
By rotating (8) appropriately and holding it by the holding means (4d), (7), the initial tension of the belt can be adjusted easily and accurately, thereby eliminating slack and overtension of the belt. It is possible to improve the service life, transmission efficiency and reliability of the belt and the bearing.

Further, when the adjusting retainer (4) is rotated by the holding means (4d) and held at the rotational position, the above adjustment can be extremely easily performed only by rotating the holding means (4d).

Further, the belt tension / position adjusting mechanism (39) is simplified in structure by using the retainers (4) and (8) that support the bolt portions (35a) and (36a) of the ball screw mechanisms (35) and (36). To do.

Furthermore, in the configuration provided with the worm gear mechanisms (4c) and (4d), the adjustment can be performed steplessly, and the accuracy is high,
Moreover, since it has a rotation and holding function, it has good workability.

When the toothed ring (7) is used as the holding means,
The adjustment retainer (8) is held securely and can be made compact.

Then, when the adjusting mechanism (39) is arranged on each of the screw devices (35) (36) on the primary side and the secondary side, the initial tension and position of the belt are properly adjusted by appropriately adjusting both adjusting mechanisms. It is possible to eliminate misalignment of the belt.

[Brief description of drawings]

FIG. 1 is a sectional view showing a belt type continuously variable transmission according to the present invention. 2 is a schematic diagram showing a continuously variable transmission to which the present invention can be applied, FIG. 3 is a diagram showing the operation of each element thereof, and FIG. 4 is a sectional view showing the continuously variable transmission. FIG. 5 is a sectional view showing a conventional example. 4,8 …… Adjustment retainer, 4c …… Warm wheel, 4d…
… Holding means (worm), 7 …… Toothed ring, 7a ……
Tooth, 8c …… Tooth, 30 …… Belt type continuously variable transmission, 30a ……
Secondary shaft, 30b …… Primary shaft, 31
…… Primary pulley, 32 …… Secondary pulley, 31a,
32a …… fixed sheave, 31b, 32b …… movable sheave, 33 …… belt, 34 …… pressure adjusting cam mechanism, 35,36 …… ball screw device, 35a, 36a …… bolt part, 35b, 36b …… nut part , 35c,
36c …… Gear part, 3b, 3c …… Thrust bearing, 15 ……
Case, 39 ... Adjustment mechanism, 100 ... Shift operation device.

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Shigekazu Ohara 10 Takane, Fujii-cho, Anjo City, Aichi Prefecture Aisin Warner Co., Ltd. (56) References JP-A-62-13853 (JP, A)

Claims (6)

(57) [Claims] 1. A primary and secondary pulley each comprising two sheaves supported by a shaft and capable of relative movement in the axial direction, and a pressure adjusting mechanism for applying an axial force corresponding to a transmission torque to at least one of these pulleys. A belt wound around the pulleys, a movable sheave rear surface of the pulleys, and a bolt portion and a nut portion screwed to the bolt portion. Either one of them is connected to each other in the rotational direction via a gear part and the other is connected to a fixed member, and the movable sheave of both pulleys is moved in the axial direction based on the relative rotation of the bolt part and the nut part. A side and a secondary side screw device, and a speed change operation device that is connected to the gear part and applies the relative rotation to the bolt part and the nut part of the screw device. In the belt type continuously variable transmission, between the other of the bolt portion and the nut portion of at least one of the screw devices and the fixing member, the axial movement of the fixing member is restricted and the rotation is made possible. An adjusting retainer that is disposed and integrally connected to the other in the rotational direction; and a holding unit that holds the adjusting retainer at an appropriate rotation position, and the bolt portion and the bolt portion based on the rotation of the adjusting retainer. By changing the axial relative position of one of the nut parts to the other,
A belt-type continuously variable transmission characterized by comprising an adjusting mechanism for adjusting the initial physical tension of the belt. 2. The belt type continuously variable transmission according to claim 1, wherein the screw device is a ball screw device. 3. The belt type continuously variable transmission according to claim 1, wherein the adjusting retainer is rotated by the holding means and is held at the rotating position. 4. The belt type non-use belt according to claim 3, wherein the adjusting retainer has a worm wheel on its outer diameter flange portion, and the holding means is a worm that meshes with the worm wheel. Gearbox. 5. The adjusting retainer has a large number of teeth on its outer diameter flange portion, and the holding means is a toothed ring which can be selectively meshed with the teeth and fixed in a predetermined position. 2. A belt type continuously variable transmission according to claim 1. 6. The belt type continuously variable transmission according to claim 1, wherein the adjusting mechanism is provided in each of the screw devices on the primary and secondary sides.