JP2744038B2 - Belt-type continuously variable transmission - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (A) Industrial application field The present invention relates to a belt formed by winding a belt made of metal or the like (including a chain type) around primary and secondary pulleys each comprising a movable sheave and a fixed sheave. The present invention relates to a continuously variable transmission (CVT), and more particularly to a structure of an operating device of a mechanical actuator such as a ball screw device that moves a movable sheave of a primary and a secondary pulley in an axial direction.

(B) Conventional technology Recently, automatic transmissions incorporating a belt-type continuously variable transmission have been attracting attention as automobile transmissions due to demands for improving the fuel consumption rate and the like.

Conventionally, as disclosed in JP-A-62-159848 and JP-A-63-158353, an axial force corresponding to a transmission torque is applied to a pulley by a pressure adjusting cam mechanism and a ball screw is used. A belt-type continuously variable transmission in which the effective diameter of the pulley is adjusted by the device has been devised.

When the movable sheaves of the primary and secondary pulleys are moved in the same axial direction by the same amount in the axial direction, the movable sheave of the belt type continuously variable transmission differs from the original movement amount of the movable sheave defined by the belt. The rotating portions of the primary and secondary ball screw devices are linked via a non-circular gear, and the movement amount of the movable sheave by the ball screw device is corrected so as to match the original movement amount of the movable sheave.

(C) Problems to be Solved by the Invention By the way, since the above-mentioned non-circular gear lacks continuation of one or more rotations, the meshing of a pair of non-circular gears is suppressed to one or more rotations. In the above-described conventional device in which the circular gear and the non-circular gear are fixed, the circular gear meshes with the circular gear mounted on one ball screw device, and the non-circular gear meshes with the non-circular gear mounted on the other ball screw device. The rotation of the ball screw device is also limited to one rotation. For this reason, in the ball screw device, it is necessary to select a lead that can perform a full stroke of the sheave in one rotation or less, and in order to secure a predetermined load capacity, the axial dimension becomes long, and shortening is required. As a result, the number of balls is reduced, and there is a possibility that a sufficient load capacity cannot be secured.

Also, if the circular and non-circular gears fixed to the countershaft are reduced in size to make them compact, the gears meshing with the gears on the ball screw device side have a relatively large diameter because they are fixed to the outer peripheral portion of the female screw portion. Therefore, the rotation of the counter shaft is increased and transmitted to the rotating portion of the ball screw device, and the rotation of the non-circular gear is limited to one rotation or less, so that it is necessary to further increase the lead of the ball screw device. As a result, it is difficult to achieve compactness by reducing the gear diameter of the countershaft.

Therefore, the present invention provides a belt-type continuously variable transmission that can transmit a plurality of rotations to a mechanical actuator such as a ball screw device while using a non-circular gear, thereby solving the above-described problems. It is intended to do so.

(D) Means for Solving the Problems The present invention has been made in view of the above circumstances, and for example, as shown in FIGS. 1 and 2, the shafts (2) and (3) are respectively provided. A primary pulley (5) and a secondary pulley (6) comprising two sheaves (5a), (5b), (6a) and (6b) supported and capable of relative movement in the axial direction, and both pulleys (5) , (6) and the movable sheave (5
b) and (6b) in a belt-type continuously variable transmission (1) including mechanical actuators (10) and (11) such as ball screw devices that move in the axial direction. Mechanical actuator (10), (1
The rotating parts (for example, female threaded parts) (10b) and (11b) of 1) are interlocked with each other by a torque transmitting device (12), and are connected to the torque transmitting device by a rotary driving device (13) (see FIG. 3). And a pair of non-circular gears (15) and (16) meshing with each other are interposed in the torque transmitting device (12).
Then, the one non-circular gear (15) is connected to a speed increasing device (12a).
And interlocked with the one rotating part (11b) via
The other non-circular gear (16) is interlocked with the other rotating part (10b) via a speed increasing device (12b).

As an example, the pair of non-circular gears (15) and (16) are fixed to counter shafts (17) and (19), respectively, and large gears (20a) and
(21a) and the gear units (20) and (21) composed of small gears (20b) and (21b) are rotatably supported, and the gear unit (21 or 21) supported on the one counter shaft (17 or 19) is provided. The large gear (21a or 20a) of (20) is engaged with the gear (22b or 22'b) fixed to the other rotating part (10 or 11), and the small gear (21b or 20b) is connected to the other counter. Gears (19a or 17) fixed to a shaft (19 or 17)
a).

(E) Operation Based on the above configuration, the rotation of the primary pulley (5) is transmitted to the secondary shaft (3) via the belt (7) and the secondary pulley (6). The torque from the rotary drive device (13) such as an electric motor is transmitted to the primary and secondary mechanical actuators (for example, ball screw devices) (10) and (10) via the torque transmission device (12).
(11) are transmitted to the rotating parts (10b) and (11b), and the mechanical actuator is moved in the axial direction based on the rotation of these rotating parts to move the movable sheaves (5b) and (6b), respectively.
The belt-type continuously variable transmission (1) is continuously variable by changing the effective belt diameter of the primary and secondary pulleys (5) and (6).

At this time, a pair of non-circular gears (15) and (16) intervene in the torque transmission device (12) that interlocks the primary and secondary mechanical actuator rotating parts (10b) and (11b). The amount of rotation of the rotating part has been corrected to match the amount of axial movement of the sheave with the original amount of movement defined by the belt (7), but one rotation of the non-circular gears (15) and (16). The rotation (see FIG. 6) inside the motor also transmits the rotation accelerated by the speed increasing devices (12a) and (12b) to the rotating unit, and the mechanical actuator (10) based on a plurality of rotations of the rotating unit. , (11), the movable sheave is moved in the axial direction.

Specifically, the rotation from the rotary drive device (13) is transmitted to the gear (22b) of one (eg, primary side) ball screw device (10), and the female screw portion (10b) is rotated a plurality of times to move the movable sheave. (5b) is moved in the axial direction, and the gear (22b)
Is greatly reduced through a gear unit (21) composed of a large gear (21a) and a small gear (21b) and further transmitted through a gear (19a) to the other counter shaft (19), and the speed is reduced. In this state, the non-circular gears (16) and (17) mesh at a rotation angle within one rotation. The rotation corrected by the non-circular gear is increased in speed from one of the countershafts (17) via the gear (17a) and the gear unit (20), and the other (for example, on the secondary side) of the ball screw device (11). It is transmitted to the gear (22'b) and the internal thread (11b)
Is rotated several times to move the movable sheave (6b) in the axial direction.

Note that the reference numerals in parentheses are for comparison with the drawings for easy understanding, and do not limit the configuration in any way. Due to the relationship described above, some of the embodiments have different names from those of the following embodiments.

(F) Example An example in which the present invention is applied to an automatic continuously variable transmission for vehicles will be described below with reference to the drawings.

First, the automatic continuously variable transmission A will be briefly described with reference to FIG. 4. The automatic continuously variable transmission A includes a belt-type continuously variable transmission 1, a single planetary gear mechanism 40, a transfer device 80, and a reduction gear. Output member 70 comprising a device 71 and the like, and a forward / reverse switching device comprising a dual planetary gear mechanism
90, fluid coupling 101, centrifugal lock-up clutch 102
And a starting device 100 including a slip clutch 103.

Then, the planetary gear mechanism 40
R interlocks with the secondary shaft 3 of the continuously variable transmission 1,
In addition, the carrier 40C is linked to the output member 70, and the sun gear 40S is connected to the low one-way clutch F and the low coast & reverse brake B1 which constitute locking means via the transfer device 80, and the high clutch C2
And is connected to the input shaft 60 via the.

In the dual planetary gear mechanism 90, the sun gear 90S is connected to the input shaft 60, and the carrier 90C is connected to the primary shaft 2 of the continuously variable transmission 1 and connected to the input shaft 60 via the forward clutch C1. Ring gear 90R is connected to reverse brake B2.

Based on the above configuration, each clutch, brake and one-way clutch in the automatic continuously variable transmission A operate at each position as shown in FIG. Note that * indicates that the lock-up clutch 102 can be appropriately operated by centrifugal force.

More specifically, in the low speed mode L in the D range, the low one-way clutch F operates in addition to the connection of the forward clutch C1. In this state, the rotation of the engine crankshaft is transmitted to the input shaft 60 via the lock-up clutch 102 and the slip clutch 103 or via the flow coupling 101, and further the dual planetary gear device 90
And transmitted to the carrier 90C via the forward clutch C1. Therefore, the dual planetary gear mechanism 90 rotates integrally with the input shaft 60, transmits the forward rotation to the primary shaft 2 of the belt-type continuously variable transmission 1, and further rotates the rotation appropriately shifted by the continuously variable transmission 1. The power is transmitted from the secondary shaft 3 to the ring gear 40R of the single planetary gear device 40. On the other hand, in this state, the sun gear
40S is stopped by the low one-way clutch F via the transfer device 80, so that the rotation of the ring gear 40R is taken out of the carrier 40C as decelerated rotation, and further transmitted to the axle shaft 73 via the deceleration gear device 71 and the like. .

In the high speed mode H in the D range, the high clutch C2 is connected in addition to the forward clutch C1.
In this state, similarly to the above, the forward rotation appropriately shifted by the continuously variable transmission 1 is taken out from the secondary shaft 3 and input to the ring gear 40R of the single planetary gear device 40. On the other hand, at the same time, the rotation of the input shaft
The torque is transmitted to the sun gear 40S of the single planetary gear mechanism 40 via the transfer device 80, whereby the torque of the ring gear 40R and the sun gear 40S is combined by the planetary gear mechanism 40 and output from the carrier 40C. At this time, since rotation against the reaction force is transmitted to the sun gear 40S via the transfer device 80, a predetermined plus torque is transmitted via the transfer device 80 without causing torque circulation. Then, the combined torque from the carrier 40C is transmitted to the axle shaft 73 via the reduction gear device 71 and the like.

In the operation in the D range, the motor is free when the reverse torque is applied (during engine braking) based on the one-way clutch F. However, in the S range, in addition to the low one-way clutch F, the low coast & reverse brake B1 is used.
Operates to transmit power even when reverse torque is applied.

In the R range, the reverse brake B2 operates together with the low coast & reverse brake B1. In this state, the rotation of the input shaft 60 is input to the belt-type continuously variable transmission 1 as reverse rotation from the carrier 90C based on the ring gear 90R being fixed by the dual planetary gear mechanism 90. On the other hand, based on the operation of the low coast & reverse brake B1, the sun gear of the single planetary gear device 40
40S is fixed, so that the reverse rotation from the continuously variable transmission 1 is reduced by the planetary gear mechanism 40 and the output member 70
Is taken out.

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

The continuously variable transmission A has a transmission case 25 composed of three parts, and the input shaft 60 and the primary shaft 2 of the continuously variable transmission 1 are coaxially and rotatably supported by the case 25 so as to be rotatable. The secondary shaft 3 and the gear shaft 70a of the continuously variable transmission 1 are rotatably supported coaxially to form a second shaft. Further, on the first shaft, a starting device 100, an operation unit 50 including a forward clutch C1, a high clutch C2, a low coast and reverse brake B1, a reverse brake B2, and a low one-way clutch F, and the forward switching device are configured. A dual planetary gear mechanism 90 and a hydraulic pump 61 are provided,
A single planetary gear mechanism 40 is provided on the second shaft.

The starting device 100 includes a fluid coupling 101, a lock-up clutch 102 including a centrifugal clutch, and a slip clutch 103. The slip clutch 103 has a cam mechanism 105 that generates an axial force corresponding to the load torque.
The cam mechanism presses and acts on the slip plate and the disk of the slip clutch, and increases the torque capacity of the slip clutch 103 in response to an increase in load torque.

Also, on the engine side of the input shaft 60, a projecting portion 25
a is protruding, and a transfer device is provided on the protruding portion 25a.
80 input sprockets 81 are supported via bearings. Further, the hub portion of the sprocket 81 is connected to the case projecting portion 25a via a one-way clutch F, and a flange extending from the sprocket 81 in the outer radial direction has an inner peripheral surface thereof. The input shaft 60 is connected via a high clutch C2 formed of a multi-plate clutch, and a low coast and reverse brake B1 formed of a multi-plate brake is interposed between the outer peripheral surface and the case 25.

A sun gear 90S (see FIG. 4) of the dual planetary gear mechanism 90 is spline-coupled to a tip portion of the input shaft 60, and a flange extends in the outer diameter direction. The end of the input shaft 60 is fitted and aligned with the primary shaft 2 of the belt-type continuously variable transmission 1 via a bush, and a carrier 90C is spline-coupled to the shaft 2. Further, a first pinion 90P1 and a second pinion 90P2 are supported on the carrier 90C, and a connecting member is extended in an outer radial direction, and a flange between the inner side of the connecting member and the input shaft 60 is formed. A forward clutch C1 including a multi-plate clutch is interposed between the outer clutch and the outer diameter side. Further, a reverse brake B2 composed of a multi-plate brake is interposed between the outer peripheral side of the support member fixing the ring gear 90R and the case 25.

An actuator unit 51 is provided in a portion between the low coast & reverse brake B1 and the high clutch C2 and the reverse brake B2 and the forward clutch C1 in the operation unit 50, and the actuator unit 51 is adjacent to the actuator unit 51. And a low-speed mode switching device actuator 51b. The actuator unit 51 has a motor for a forward / reverse switching device and a motor for a low / high speed mode switching device which are arranged at a predetermined interval in the circumferential direction, and these motors include a commutator motor and a step motor. An electric motor such as a rotating magnetic field motor, a servo motor, and an ultrasonic motor is provided, and holding means such as an electromagnetic brake is provided so as to be able to hold the motor at a predetermined rotation position. Further, in the case 25, female screw portions of ball screw devices 52 and 53 for a front / rear switching device and a low-high speed mode switching device are fixedly provided in the case, and the male screw portions of the ball screw devices are respectively described above. It meshes with the output gear of the motor via a gear, and a connecting member is connected to each male screw portion. The connecting member connected to the ball screw device 52 for the forward / reverse switching device engages the forward clutch C1 by the axial movement in one direction and engages the reverse brake B2 by the axial movement in the other direction. The connecting member connected to the ball screw device 53 for the low / high speed mode switching device engages the high clutch C2 by the axial movement in one direction and the low coast & reverse brake by the axial movement in the other direction. Engage B1.

In addition, the continuously variable transmission 1 is, as shown in detail in FIG.
It comprises a primary pulley 5, a secondary pulley 6, and a belt 7 wound around these pulleys, and both pulleys comprise fixed sheaves 5a, 6a and movable sheaves 5b, 6b, respectively. The belt 7 has a large number of metal pieces,
These pieces contact the primary and secondary pulleys 5 and 6 in a lubricated state and transmit torque, so that the friction between the pieces and the pulleys 5 and 6 is relatively small, and as a result, the angle of the contact surface between the pieces and the pulleys Is set larger than the stop friction angle. That is, the belt 7 can move in the radial direction by the axial movement of the pulleys 5 and 6. The fixed sheave 5a of the primary pulley 5 is rotatably supported by the case 25 by a roller bearing 30, and the base end of the primary shaft 2 bulges in the outer diameter direction to form a flange 2a. A pressure adjusting cam mechanism 9 is interposed between the flange portion 2a and the rear surface of the fixed sheave 5a. And the pressure adjusting cam mechanism 9
The fixed side cam portion 9a, which is spline-coupled to the primary shaft 2 and whose axial movement is restricted by the flange portion 2a, is spline-coupled to the fixed sheave 5a and press-contacts via a disc spring. Movable side cam portion 9b,
It is composed of rollers interposed between both cam portions, and applies an axial force corresponding to the transmission torque to the fixed sheave 5b. The boss portion of the fixed sheave 5a extends toward the movable sheave 5b, the inner peripheral surface of which is fitted to the primary shaft 2, and the outer peripheral surface thereof has a plurality of rows of ball spline mechanisms (linear ball bearings). The boss portion of the movable sheave 5b is supported via the movable member 21 only in the axial direction. That is, movable sheave
5b is fitted to the fixed sheave boss portion only through the ball without receiving sliding frictional resistance.

A ball screw device 10 is provided on the back surface of the movable sheave 5b. The ball screw device 10 includes a male screw portion 10a, a female screw portion 10b, and a ball, and the circulate through which the ball is circulated in a return passage. Consists of type.
Further, the ball screw device is formed of a single thread, and the female screw portion 10b is formed with a concave groove for about one turn and a top return passage. The male screw portion 10a is more axially than the female screw portion. The adjustment member has a long configuration, and is axially and radially restrained and supported by the shoulder of the case 25.
The rear end is fixed to 26. The adjusting member 26 rotatably supports the primary shaft 2 along the rear cylindrical portion of the boss portion of the fixed sheave 5a by a roller bearing 33, and meshes with the worm 34, and rotates by the operation of the worm 34. The initial tension of the belt 7 and the running center of the belt 7 can be adjusted based on the relative rotation of the male screw 10a with respect to the female screw 10b. Also, its female screw part
An automatic alignment mechanism 22 is fixed to 10b, and a thrust ball bearing 23 is interposed between the automatic alignment mechanism 22 and the rear surface of the movable sheave 5b. The thrust bearing 23 is composed of a number of balls 23 held in a cage.
The ball 23b is in direct contact with a concave portion formed on the rear surface of the movable sheave 5b, and the opposite side of the movable sheave is in contact with the race 23a. The other side surface of the race 23a is formed of a spherical convex surface, and the spherical support surface of the automatic alignment mechanism 22 is in close contact with the spherical convex surface. The spherical support surface 22a
Consists of a concave surface facing obliquely downward and having a focal point at the axis of the primary shaft 2, and a self-aligning mechanism 22 formed at a protruding portion extending obliquely along the spherical support surface 22a, at the tip of the protruding portion. And a key fixing portion 22c integrally fixed to the gear 22b and the female screw portion 10b in the rotation direction and the axial direction. Also, a predetermined number of disc springs are provided between the support plate 35, which is prevented from moving in the axial direction by the inner race of the roller bearing 33 held by the adjusting member 31, and the rear surface of the movable sheave 5b. A biasing member 36 is provided, and the biasing member 36 carries a part of the belt narrow pressure load and lowers the support load of the ball screw device 10 and the bearing 23. A flange 27 is fixed to the tip of the primary shaft 2 by screw connection, and an automatic alignment mechanism 28 is fixed to the flange. The self-aligning mechanism 28 has a spherical support surface 28a having a convex surface facing obliquely outward and having a focal point on an extension of the axis of the shaft 2. Furthermore,
A thrust ball bearing 29 is interposed on the back of the self-centering mechanism 28 and the adjusting member 32, and the bearing 29 is composed of a number of balls 29b held by a gauge and one race 29a.
have. The ball 29b is in direct contact with the concave portion formed on the back surface of the adjusting member 26, and the race 29a in contact with the other side surface of the ball has a spherical shape closely contacting the spherical support surface 28a of the automatic alignment mechanism 28. It has a concave surface.

On the other hand, the secondary pulley 6 has its fixed sheave 6a integrally with the secondary shaft 3 and a roller bearing on the case 25.
30 'is rotatably supported through, and the boss portion 6b ₁ of the movable sheave 6b, similar ball spline 21 and the ball spline described above' by sliding only through only the ball to the secondary shaft 3 It is freely inserted. Further, a ball screw device 11 similar to that described above is disposed on the back surface of the movable sheave 6b, and its male screw portion 11a is fixed to an adjusting member 26 'similar to the adjusting member 26, and accordingly, The member 26 'supports the secondary shaft 3 via a roller bearing 33', and has a worm 34 '.
, The initial tension of the belt 7 and the running center line can be adjusted in cooperation with the adjustment member 26 on the primary side.
An automatic alignment mechanism 22 'is fixed to the female screw portion 11b, similarly to the primary side, and a thrust ball bearing 23' is provided on the back of the automatic alignment mechanism 22 'and the movable sheave 6b. Intervening. Further, between the support plate 35 'fixed to the shaft 3 and the rear surface of the movable sheave 6b, an elastic biasing member 36' similar to that on the primary side is provided. In addition, the secondary shaft 3 has a base end whose diameter is expanded and a hole 3a for receiving the gear shaft 70a is formed.
Further, an end of the shaft enlarged diameter portion 3b protrudes in the outer radial direction to form a flange portion 3cb. A fixed sheave 6a is fitted to a tip end of the shaft 3 via a key k, and a nut 38 Are screwed together to stop the fixed sheave 6a.
An automatic alignment mechanism 28 'having a spherical support surface 28'a having a convex surface and having a focal point on an extension of the axis of the shaft 3 is fixed to the flange portion 3c, similarly to the primary side, and The self-centering mechanism 28 'and the adjusting member 26'
A thrust ball bearing 29 'having a ball 29'b directly in contact with the back surface of the member and a race 29'a having a spherical concave surface in close contact with the spherical support surface 28'a is interposed.

In FIG. 1, those indicated by reference numerals 39, 39 '
Primary side and secondary side of the fixed sheave 5a, 6a is a groove for the detected formed on the tip of, by recessed grooves 39, 39 are counted to electromagnetic sensors S _1, S _2, the primary, respectively The rotation speeds of the shaft 2 and the secondary shaft 3 are detected.

As shown in FIG. 1, FIG. 2, and FIG. 6 to FIG. 8, an operation device 130 is provided at a portion where the primary shaft 2 and the secondary shaft 3 form a triangle. The operating device 130 includes bearings 132, 1 in the case 25.
32, the first and second countershafts 17 and 19 are supported by the first countershaft 17
A gear unit 21 having a large gear 21a and a small gear 21b is rotatably supported, and a large gear 17a
Are fixed integrally. A large gear 19a is integrally fixed to the second countershaft 19, and a gear unit 20 having a small gear 20b and a large gear 20a at the distal end.
Are rotatably supported. Further, as shown in FIG. 6, non-circular gears 15, 16 meshing with each other are fixed to the protruding portions of the counter shafts 17, 19, which protrude from the bearing 132, so that they are non-linearly related to each other. These non-circular gears 15 and 16 are
It is covered with a protective cover 131 fixed to 5. Then, as shown in detail in FIG. 7, the first counter shaft
The gear unit 21 rotatably supported on the gear 17 has a large gear 21a meshed with a gear 22b of the primary-side ball screw device 10 and a gear 136b from the electric motor 13, which will be described later. Second counter shaft 19
Meshes with a large gear 19a fixed to the second gear shaft to form a speed increasing device 12b in the transmission path from the second counter shaft 19 (accordingly, a reduction gear in the transmission path from the gear 22b of the ball screw device). As shown in detail in FIG. 8, the gear unit 20 rotatably supported on the second counter shaft 19 has its large gear 20a meshed with the gear 22'b of the secondary-side ball screw device 11. And the small gear 20b meshes with the large gear 17a fixed to the first counter shaft 17, and the speed increasing device 12a (accordingly, the gear 22'b of the ball screw device) in the transmission path from the first counter shaft 17 is used. (A reduction gear in a transmission path from the transmission). The large gears 21a, 21a have a wide meshing surface, and the meshing relationship is always maintained even if the narrow gears 22b, 22'b are moved in the axial direction by the ball screw device. .

On the other hand, as shown in FIG. 3 and FIG. 9, the electric motor 13 for gear shifting operation is fixed outside the case 25, and the electric motor 13 is similar to the electric motor in the operation unit 50 described above. And an electromagnetic brake 145 that can be held at a predetermined position when the motor is not energized. The output gear 133 of the motor 13 is a reduction gear 1 including a gear unit 135 having a large gear 135a and a small gear 135b and a gear unit 136 having a large gear 136a and a small gear 136b.
Via 43, the above-mentioned ball screw device is interlocked with the torque transmitting device 12, that is, the small gear 136b is meshed with the large gear 21a to transmit power.

Each of the gears of the torque transmission device 12 and the reduction device 143 is formed of a spur gear or a helical gear, and is capable of reversible transmission and highly efficient power transmission.

Further, the second counter shaft 19 is offset so that the large gear 20a of the gear unit 20 rotatably supported by the second counter shaft 19 does not wrap around the primary pulley 5 in a side view. .

As shown in FIG. 3, the single planetary gear mechanism 40 is disposed on a gear shaft 70a constituting a second shaft, and its ring gear 40R is connected to a flange of the secondary shaft 3 of the belt-type continuously variable transmission 1. It is connected to the part 19. A sprocket 82 is rotatably supported integrally with the sun gear 40S on the gear shaft 70a.
And a carrier 40C that rotatably supports the pinion 40P
Has been fixed.

On the other hand, a silent chain 83 is wound between a sprocket 82 integral with the sun gear 40S 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 the intermediate shaft 72. Further, a small gear 71d is formed on the intermediate shaft 72, and the gear 71d meshes with a ring gear 75a fixed to the differential gear device 75,
The reduction gear 71 is constituted. Further, left and right front axle shafts 73 extend from the differential gear device 75.

 Next, the operation of the present embodiment will be described.

The rotation of the engine crankshaft is transmitted to the input shaft 60 via the fluid coupling 101 when the vehicle starts, and thereafter via the centrifugal lock-up clutch 102 and the slip-slatch 103. The rotation of the input shaft 60 is switched by the forward / backward switching device 90 composed of a dual planetary gear mechanism by the operation of the forward clutch C1 or the reverse brake B2 based on the forward switching device actuator 51a in the operation section 50, and the forward rotation or The reverse rotation is transmitted to the fixed cam portion 9a of the pressure adjusting cam mechanism 9. The operation of the high clutch C2 or the low coast & reverse brake B1 based on the actuator 51b for the low / high speed mode switching device in the operation unit 50, and the engagement / disengagement of the low one-way clutch F
By the overrun, as described above, the low / high speed mode switching device 40 including the single planetary gear mechanism can be switched to the low speed mode L or the high speed mode H.

The torque transmitted to the fixed side cam portion 9 of the pressure adjusting cam mechanism 9 is transmitted to the movable sheave 5b of the primary pulley 5 via the roller and the movable side cam portion 9b, and the axial force corresponding to the transmitted torque. To the fixed sheave 5a and thus via a belt 7
An axial force corresponding to the transmission torque is applied to the whole. Further, the torque of the fixed sheave 5a is transmitted to the movable sheave 5b through the ball spline 21, and the belt 7 is pinched by the axial force based on the pressure adjusting cam mechanism 9, and the secondary pulley is 6 is transmitted. At this time, the axial reaction force from the belt 7 acts on the fixed sheave 5a and the movable sheave 5b, but the axial force from the fixed sheave 5a is carried by the flange portion 2a of the shaft via the pressure adjusting cam mechanism 9, and The axial force from the movable sheave 5b is applied to the thrust ball bearing 23, the automatic alignment mechanism 22, the ball screw device 10 in a predetermined state, the adjusting member 26, the thrust ball bearing 29, and the automatic alignment mechanism 28.
Through the flange portion 27 fixed to the shaft 2, whereby the axial force is received in a closed loop acting as a tensile stress of the primary shaft 2. A part of the axial force acting on the movable sheave 5b is directly transmitted from the back of the sheave via the elastic urging member 36 and the support plate 35 to the shaft 2.
The axial force acting on the thrust bearings 23 and 29 and the ball screw device 10 is reduced.

The torque from the belt 7 is applied to the secondary pulley 6
And transmitted to the secondary shaft 3 via the key k and the ball spline 21 '. At this time, the fixed sheave is used on the secondary side as well as on the primary side.
The axial reaction force acting on the movable sheave 6b is directly supported by the nut 3 on the shaft 3 while the axial reaction force acting on the movable sheave 6b is controlled by the thrust ball bearing 23 ', the ball screw device 11, the adjusting member 26', and the thrust ball bearing 29. 'And the flange 3c. Similarly, a part of the axial force acting on the movable sheave 6b is directly applied to the elastic urging member 36 'and the support plate 35'.
Through the shaft 3.

At this time, on the primary side and the secondary side, even if the movable sheaves 5b, 6b have a key, the thrust ball bearings 23, 23 'are automatically aligned by the automatic alignment mechanisms 22, 22', and the balls 23b, 23 'B is automatically adjusted so as to uniformly hit the rear surfaces of the movable sheaves 5b and 6b all around. The adjustment member supported by the shoulder of the case 25
Even if the primary or secondary shafts 2 and 3 form a key with respect to 26 and 26 ', the balls 29b and 29'b are automatically aligned by the automatic alignment mechanisms 28 and 28' so that the balls 29b and 29'b It is automatically adjusted to hit the back uniformly over the entire circumference.

In addition, based on a shift command from the control unit, the electric motor 13
Rotates, the large gear 21a engaged with the first counter shaft 17 via the reduction gear 143 rotates, and the gear 2
The self-aligning mechanism 22 and the female screw part 10b integral therewith are rotated by the gear part 22b meshing with 1a. Then, the adjustment member 2
The female screw portion 10b moves in the axial direction with respect to the male screw portion 10a whose rotation is prevented by 6, and the thrust ball bearing 23
Moving the movable sheave 5b through the primary pulley 5
Change the effective diameter of the belt. On the other hand, the rotation of the large gear 21a is greatly reduced by the meshing of the small gear 21b and the large gear 19a of the gear unit 21, transmitted to the second counter shaft 19, and further transmitted through the non-circular gears 16 and 15. 1 is transmitted to the counter shaft 17. The rotation of the first counter shaft 17 is increased through the large gear 17a, the small gear 20b of the gear unit 20, and the large gear 20a, and the rotation of the large gear 20a The power is transmitted to the gear portion 22'b. Due to the rotation of the gear portion 22'b, the female screw portion 11b integral with the gear portion 22'b rotates relative to the female screw portion 11a in a fixed state and moves in the axial direction.
The movable sheave 6b is moved via 23 'to change the effective belt diameter of the secondary pulley 6. At this time, the movement amounts of the primary and secondary pulleys 5 and 6 and the movement amount of the belt 7 do not linearly correspond to each other, but by transmitting through the non-circular gears 15 and 16, the difference between the two movement amounts is appropriate. Is absorbed by Also, from the structural point of view, the non-circular gears 15, 16 are pressed within one rotation, but by providing the non-circular gears on the first and second counter shafts 17, 19, which are reduced in speed, the non-circular gears 15, 16 are provided. The primary and secondary gear portions 22b, 2 are provided while 16 rotations are held within one rotation.
2′b is linked with the decelerated rotation, and the ball screw devices 10, 11
, So that the ball screw device can obtain a predetermined stroke with a predetermined lead.

At this time, for example, when the electric motor 13 is rotated in the upshift direction of the continuously variable transmission 1, the female screw portion 10b of the ball screw device 10 on the primary side is elongated, and the female screw portion 11b of the ball screw device 11 on the secondary side is expanded. Shrink. Then, the primary-side movable sheave 5b moves in the pulley radially expanding direction (rightward in the drawing axial direction) together with the female screw portion 10b. At this time, the boss portions of both movable sheaves 5b cause any frictional sliding due to the ball spline 21. Move in the axial direction. Further, the secondary shaft movable sheave 6b moves in the pulley diameter reduction direction (right side in the drawing axial direction) based on the force from the belt 7 caused by the pressure adjusting cam mechanism 9 as the female screw portion 11b moves. When the ball spline is
By 21 ', the movable sheave 6b moves in the axial direction without any frictional sliding. Further, the primary-side ball screw device 10 and the secondary-side ball screw device 11 are formed of a reversible transmission device that can convert a rotational force into an axial force and can convert an axial force into a rotational force.
Since 10b and 11b are linked by a reversible transmission device 12 composed of a spur gear or a helical gear, the axial force from the belt 7 on the secondary pulley 6 is converted and transmitted to the axial force of the primary pulley 5 via the reversible transmission device. Have been. Therefore, when shifting, the primary side ball screw device
The axial force that acts on the movable sheave 5b is
Of the primary side pulley 5 and the secondary pulley 6 on the belt 7 based on the fact that there is almost no axial movement resistance and the reversible transmission
13 has a small torque capacity and is capable of high-speed shifting operation. The pressure adjusting cam mechanism 9 also generates a relatively small axial force that does not require the moving resistance of the movable sheave 5b. Is enough. When the electric motor 13 rotates in the downshift direction, the secondary-side ball screw device 11
Is extended and the primary-side ball screw device 10 is contracted, and the speed change operation is performed in the same manner as described above.

Further, when the vehicle is in a high speed state, that is, when the belt-type continuously variable transmission 1 is in the speed increasing state and the vehicle is stopped by applying a sudden brake, the belt-type continuously variable transmission 1 may not be able to return to the minimum speed state. is there. In this case, as described above, the ball screw devices 10 and 11 have a relatively small lead angle, there is no sliding frictional resistance of the movable sheaves 5b and 6b, and the static friction angle between the belt 7 and the pulleys 5 and 6 is the same. Because it is smaller than the contact angle,
Even when the belt-type continuously variable transmission 1 is stopped, the movable sheave can move in the axial direction, so that even after the vehicle stops, the electric motor 13 continues to rotate and the movable sheaves 5b, 6b
In the axial direction to return the continuously variable transmission 1 to the lowest speed state.

And the rotation of the primary shaft 3
Ring gear 40R of single planetary gear mechanism 40 from 3c
As described above, the speed is simply reduced by the planetary gear mechanism or combined with the rotation from the transfer 80 and transmitted to the gear shaft 70a. Further, the rotation of the gear shaft 70a is transmitted to the differential gear device 75 via the reduction gear 71, and is transmitted to the left and right front axle shafts 73.

Next, a partially modified embodiment will be described with reference to FIG.

In this embodiment, the gear units 21 and 20 are rotatably supported by the counter shafts 17 and 19, respectively, whereas the gear units are separately supported. That is, the torque transmission device 12 has four counter shafts.
Non-circular gears 15 and 16 are fixed to two shafts 17 and 19 at the center, and large gears 17a and 19a are fixed to the two shafts 17 and 19, respectively. In addition, counter shaft 1
A large gear 21a and a small gear 21b are fixed to 7 ', and the large gear 21a is a female screw portion 10b of the primary side ball screw device 10.
Meshes with the gear 22b fixed to the
Meshes with the large gear 19a to form a gear unit 21 serving as a speed increasing device on a transmission path from the non-circular gear.
Also, the large gear 20a and the small gear 2
0b is fixed, and the large gear 20a is fixed to the female screw portion 11b of the secondary-side ball screw device 11.
And the small gear 20b meshes with the large gear 17a to form a gear unit 20 that functions as a speed increasing device on a transmission path from the non-circular gear.

In the above-described embodiment, the belt type continuously variable transmission 1 is applied to the automatic transmission A that switches between the low speed mode and the high speed mode in combination with the single planetary gear mechanism 40. Of course, the present invention may be applied to other types of automatic transmissions such as an automatic transmission in which a step transmission is combined.

(G) Advantages of the Invention As described above, according to the present invention, the non-circular torque transmission device (12) that interlocks the rotating parts (10b) and (11b) of both mechanical actuators (10) and (11). Gear (15),
With the interposition of (16), the moving amount of the movable sheaves (5b) and (6b) matches the original moving amount of the movable sheave specified by the belt (7), but the non-circular gear (15 ),
Although the meshing of (16) is limited to one rotation or less, one of the non-circular gears (15) is interlocked with one of the rotating parts (11b) via the speed increasing device (12a), and the other is non-circular. The non-circular gear (16) is connected to the other rotating part (10b) via the speed increasing device (12b).
, A plurality of rotations can be transmitted to the mechanical actuator, whereby the mechanical actuator can generate sufficient axial force with a predetermined lead or the like over the full stroke of the movable sheave.

In particular, mechanical actuators use ball screw devices (1
0) and (11), the ball screw device can optimally set its lead to the full stroke of the movable sheaves (5b) and (6b), and set the number of balls appropriately and Load capacity can be ensured, and the axial dimension can be reduced.

In addition, the gears on the countershafts (17) and (19) can be reduced in size by the intervention of the speed increasing devices (12a) and (12b), and the non-circular gears (15) and (1
The gear diameter of 6) can also be reduced, so that the entire belt-type continuously variable transmission 1 can be reduced in size.

The counter shafts (17) and (19), which fix the non-circular gears (16) and (15), respectively,
Gear unit (21), which constitutes the devices (12b) and (12a),
Since (20) is rotatably supported, the shaft support structure of these speed increasing devices can be simplified and the size of the devices can be reduced.

Further, one counter shaft (19) supporting a gear unit (20) meshing with a gear (22'b) fixed to a rotating part (11b) of one mechanical actuator (for example, a secondary side ball screw device) (11). Since the gear (20a) of the gear unit is offset from a pulley (for example, a primary pulley) (5) on which the other mechanical actuator (10) is mounted so as not to wrap in a side view,
The gear unit (20) can be arranged at a position where it wraps in the axial direction without being interfered by the other pulley (5), and the axial dimension can be reduced.

Further, the non-circular gears (16) and (15) are fixed to the protruding portions of the counter shafts (17) and (19), and the non-circular gears are protected by the cover (131) attached to the case (25). As a result, the non-circular gears (16) and (15) can be assembled outside the case (25), and the assembling performance and maintenance performance can be improved.

[Brief description of the drawings]

FIG. 1 is a developed sectional view showing a belt-type continuously variable transmission according to the present invention, and FIG. 2 is a schematic view thereof. FIG. 3 is an overall sectional view showing an automatic transmission to which the belt-type continuously variable transmission is applied, FIG. 4 is a schematic diagram showing an outline of the automatic transmission, and FIG. It is a figure which shows operation | movement. 6 to 9 are views of each gear train viewed from the rear (left side in FIG. 1) of the belt-type continuously variable transmission, FIG. 6 is a diagram showing a non-circular gear, and FIG. FIG. 8 is a diagram showing one speed increasing device (reduction device), FIG. 8 is a diagram showing the other amplifying device, and FIG. 9 is a diagram showing a reduction device from a rotary drive device. FIG. 10 is a schematic view of a belt-type continuously variable transmission that is partially modified. DESCRIPTION OF SYMBOLS 1 ... Belt-type continuously variable transmission, 2 ... Primary shaft, 3 ... Secondary shaft, 5 ... Primary pulley, 6 ... Secondary pulley, 5a, 6a ... Fixed sheave, 5
b, 6b ...... movable _{sheave, 5a 1, 5b 1, 6b} 1 ...... boss, 7 ......
(Metal) belt, 9 ... Pressure adjustment (cam) mechanism, 10,11 ...
Mechanical actuator (ball screw device), 10a, 11a…
... Fixed part (male screw part), 10b, 11b ... Rotating part (female screw part), 12 ... Torque transmission device, 12a, 12b ... Gear speed increasing device, 1
3… Rotary drive (electric motor), 15,16… Non-circular gear, 17,19… Counter gear, 20,21… Gear unit,
20a, 21a …… Large gear, 20b, 21b …… Small gear, 22b, 22′b…
... gear, 25 ... case, 131 ... cover.

Claims (5)

(57) [Claims] 1. A primary pulley and a secondary pulley each comprising two sheaves supported by a shaft and capable of moving relative to each other in an axial direction, a belt wound around the two pulleys, and a movable sheave of the two pulleys in an axial direction. Wherein the mechanical actuator comprises a fixed portion and a rotating portion, at least in which the rotating direction is blocked by a fixed member, and the primary and the secondary. The rotating parts of the two mechanical actuators on the two sides are interlocked with each other by a torque transmitting device, transmit torque from a rotary drive device to the torque transmitting device, and a pair of non-meshed gears mesh with each other. A circular gear is interposed, and the one non-circular gear is interlocked with the one rotating unit via a speed increasing device. A belt-type continuously variable transmission, wherein the other non-circular gear is linked to the other rotating part via a speed increasing device. 2. The mechanical actuator comprises a ball screw device, wherein a male screw portion of the ball screw device is connected to a fixed member in a rotationally and axially immovable manner to constitute the fixed portion, and a female screw portion is formed. 2. The belt-type continuously variable transmission according to claim 1, wherein the rotation unit is connected to the rotation driving device to form the rotation unit, and is screwed to the male screw portion to move in the axial direction. 3. A pair of non-circular gears are fixed to a counter shaft, respectively, and a gear unit composed of a large gear and a small gear is rotatably supported on each of the counter shafts, and is supported by the one counter shaft. The belt-type continuously variable transmission according to claim 1, wherein a large gear of the gear unit is meshed with a gear fixed to the other rotating portion, and the small gear is meshed with a gear fixed to the other counter shaft. apparatus. 4. A counter shaft for supporting a gear unit meshing with a gear fixed to a rotating part of said one mechanical actuator, a gear shaft of said gear unit and a pulley on which said other mechanical actuator is mounted. The belt-type continuously variable transmission according to claim 3, wherein the belt-type continuously variable transmission is arranged at a position where the belt does not wrap. 5. The non-circular gear is fixed to a protruding portion protruding from a bearing support surface of a countershaft supported on the case via a bearing, and these non-circular gears are fixed by a cover attached to the case. The belt-type continuously variable transmission according to claim 1, which is protected.