JPH02180373A - Actuator for friction engaging device - Google Patents

Abstract

PURPOSE:To reduce the load of a torque generation mechanism by connecting the connection means operating at least two friction engaging devices to the movable part of a thrust force generation mechanism via a rolling bearing. CONSTITUTION:Torque is generated from a torque generation mechanism 1 with the electric signal from a control part C, the torque is converted into a thrust force with a thrust force generation mechanism 15 or 16, and friction engaging devices B2 and C1, or B1 and C2 are driven via connection means 4 and 6, or 7 and 8. These connection means 4 and 6, and 7 and 8 are rotatably connected to the movable parts (male screw parts) 12 and 13 of the mechanisms 15 and 16 via rolling bearings 17 and 22. Thus durability can be improved with friction resistance reduced, and also the load of a torque generation mechanism can be lightened.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Industrial Application Field The present invention relates to an actuator for operating a friction engagement device such as a friction clutch or a friction brake, and particularly to a forward/reverse drive actuator used in combination with a belt-type continuously variable transmission. It is suitable for use as an actuator for a switching device or an actuator for a low-high speed mode switching device, and specifically relates to an actuator for a friction engagement device that mechanically converts rotational force from a drive source such as a motor into thrust force.

(b) Conventional technology In general, power transmission devices such as automobiles, such as transmissions or
The wheel drive device includes a multi-disc clutch and a multi-disc (or band) brake that control each element of the planetary gear mechanism.
Also, differential lock clutch (full time system) or 2.4
A friction engagement device is used as a wheel switching clutch (part-time method).

These frictional engagement devices use a hydraulic actuator (hydraulic pressure-thrust force conversion mechanism) consisting of a piston and a cylinder to press or release the operating plate and the passive plate. There are various problems such as oil leakage, delayed response, and difficulty in fine control.

Therefore, as shown in Japanese Unexamined Patent Publication No. 63-203958, the present applicant has developed a torque generating mechanism that converts the electrical energy of an AC or DC electric motor into torque, and a screw mechanism (including a ball screw mechanism) or a cam mechanism. A torque-to-thrust force conversion mechanism (thrust force generation mechanism) that converts torque into thrust force with an increase in force, such as We have devised an actuator for frictional engagement devices configured to act on frictional engagement devices such as plate clutches, multi-disc brakes, and band brakes.

Furthermore, the present applicant operates one friction engagement device by the movement of one side of the thrust force generating mechanism, and operates the other friction engagement device by the movement of the other side, thereby operating the forward clutch and the forward clutch of the forward/reverse switching device. We have proposed an actuator suitable for use as an actuator for two frictional engagement devices that operate differently from each other, such as a reverse brake, or a high clutch and low coast/reverse brake of a low/high speed mode switching device (patent application). Showa 62-33048
No. 2; unpublished) As shown in FIG. 5, the actuator for the friction engagement device includes a ball screw mechanism 44 that constitutes a thrust force generation mechanism
or an electric motor 1 whose female screw portion 54 is fixed to the case 49 and whose male screw portion 64 constitutes a torque generation mechanism;
2, and therefore the male threaded portion 64
is screwed into the female threaded portion 54 to rotate and move in the axial direction.

And a brake connecting member 68 for operating the reverse brake B2 or the low coast reverse brake B1.
74 is connected to the male threaded portion 64 via a ball bearing 17'22', and is a clutch connecting member 84 that operates the forward clutch C1 or the high clutch C2.
．． 85 is in contact with the female threaded portion 64 with springs 88 and 94.

(c) Problems to be Solved by the Invention For this reason, based on the fact that the male threaded portion 64 constituting the movable portion of the thrust force generation mechanism moves in the axial direction while rotating, the clutch connecting member 84, 85 and the female Due to the fact that relative rotation occurs between the connecting member and the male threaded portion 64, and a relatively large pressing force is required to release the clutches C1 and C2, Relatively large frictional resistance occurs.

As a result, the load on the electric motors 1 and 2 increases, requiring a large-capacity motor, and there is a risk of delay in operation. In addition, the contact portion between the connecting members 84 and 85 and the male threaded portion 64 may be worn out. There is a risk that this may occur, resulting in decreased durability.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide an actuator for a friction engagement device that is configured to transmit thrust force from a thrust force generation mechanism to all connecting members via rolling bearings, thereby solving the above-mentioned problems. That is.

(d) Means for Solving the Problems The present invention has been made in view of the above-mentioned circumstances, and for example, as shown with reference to FIG.
5) at least two frictional engagement devices (B2.
C1) (or Bl, C2) is controlled by an actuator (lla) (or 1
1b), which includes a torque generation mechanism (2) (or 1) that converts electrical energy into torque, and a thrust force generation mechanism (15) such as a ball screw mechanism that converts the torque generated by the torque generation mechanism into thrust force. ) (or 16), and a connecting means (4, 6) that is connected to the movable part (12) (or 13) of the thrust force generating mechanism and moves in the axial direction to operate the at least two frictional engagement devices. ) (or 8.7), and the connecting means connects the thrust force generating mechanism (15) (
or 16) is connected to the movable part (12) (or 13).

Specifically, the thrust force generating mechanism (15) (or 16)
) includes a female screw portion (9) (or 10) which is fixed to the fixing member (49) in the axial and rotational directions, the torque generating mechanism (2) (or 1), and the gear (34a) (or 30).
a) Externally threaded part (12), (or 1
3), and the male screw portion is screwed into the female screw portion (9) (or 10) to constitute the movable portion that moves in the axial direction.

Moreover, the actuator (11a) for the frictional engagement device (
or 11b) is an actuator (3) for a forward/reverse switching device having a reverse brake (B2) and a forward clutch (C1), and the connecting means is an actuator (3) for a forward/reverse switching device having a reverse brake (B2) and a forward clutch (C1); Consisting of a connecting member (6) (or 7), the brake connecting member is
The clutch connecting member is provided integrally with the race of the rolling bearing (17) (or 22), and the clutch connecting member is (6).
(or 7), and comes into contact with the race.

Further, a spring means (23) for holding the clutch in an engaged state is interposed between the forward clutch (C1) and the clutch connecting member (6), and a spring means (23) is provided between the forward clutch (C1) and the clutch connecting member (6). , a return spring means (19) having a strong urging force opposing the spring means (23) is applied.

Furthermore, the frictional engagement device actuator is an actuator (1l b) for a low-high speed mode switching device having a low (coast and reverse) brake (B1) and a high clutch (C2), and the connecting means is a brake The brake connecting member (8) is provided integrally with the race of the paper bearing (22), and the clutch connecting member (7) is provided integrally with the race of the paper bearing (22). ) comes into contact with the race.

The high clutch (C2) and the connecting member (7)
) is interposed between the clutch connecting member (8) and a spring means (24) for holding the clutch in an engaged state.
A return spring means (20) having a strong urging force opposing the spring means is applied to the spring means.

Furthermore, the actuator for the forward/reverse switching device (lla
) and the actuator for the low-high-speed mode switching device (l
lb) are arranged adjacent to each other with the fixed sides of the return spring means (19) and (20) facing back to back.

(E) Effect Based on the above configuration, when the torque generating mechanism (2, 1) is in a predetermined position, one of the frictional engagement devices (C1, C2) is in an engaged state, and the other frictional engagement device ( B2.Bl
) is in a released state, and the power transmission device (3, 5) is in a predetermined state. From this state, electric energy is applied to the torque generating mechanism (2, 1) by an electric signal from the control unit (C) to generate a predetermined torque, and based on the torque, the thrust force generating mechanism (15, 1) such as a ball screw mechanism 16) When a thrust force is generated in the - direction, one of the frictional engagement bags fi (C1
, C2) is released, and the other frictional engagement device (B2
．． Bl) is engaged and the power transmission bag! (3, 5) is switched to a state different from the predetermined state.

As an example, an explanation will be given based on a specific example applied to the forward/reverse switching device (3) and the low/high speed mode switching device (5) shown in FIG. 1. When the torque generating mechanism (1) is at the home position, the spring means ( 24), the high clutch (C2) is in the released state and the four-coast and reverse brake (B1
) is also in the released state, and the row one-way clutch (F)
only in working condition.

In this state, the sun gear (3S) is fixed by the one-way clutch (F), and the low-high-speed mode switching device M (5) is in the low-speed mode consisting of a simple speed reduction mechanism. When the torque generating mechanism (1) is rotated in one direction from the home position, the male threaded portion (13) compresses the return spring means (20) and the spring means (24)
engages the high clutch (C2) and enters high speed mode. Further, when the torque generating mechanism (1) is rotated in the other direction from the home position, the male threaded portion (13) engages the low coast and reverse brake (B1). Then, when the high clutch (C2) or the brake (B1) is engaged, the electromagnetic brake is energized and the torque generating mechanism (1
) is maintained in this state.

During the above-mentioned operation, on the low-high-speed mode switching device (5) side, the connecting members (8) and (7) are connected to the male threaded portion (13) via the rolling bearing (22), so that the male Since relative rotation is freely performed between the threaded portion (13) and the connecting members (8) and (7), the high clutch (C2) can be released even when the low coast and reverse brake (B1) is engaged. Even when the brake (B1) or clutch (C2) and the connecting member (8), (
7) allows smooth contact without rubbing, and
No wear occurs between the male threaded portion (13) and the connecting members (8), (7).

This is the same on the forward/reverse switching device (3) side, and both when the reverse brake (B2) is engaged and when the forward clutch (C1) is released.
These reverse brake (B2) or forward clutch (C1) and the connecting members (4), (6) can smoothly contact each other without sliding, and the male threaded portion (12) and the connecting members (4), (8) No wear occurs between the two.

Note that the numbers in parentheses above are used to refer to Fig. 1, but they do not limit equivalent configurations, and even if they indicate the same parts, they may be given different names from those in the example. Some are listed.

In addition, this frictional engagement actuator is applicable not only to the above-mentioned forward/reverse switching device and low/high speed mode switching device, but also to other power transmission devices such as a transmission that changes the transmission path by engaging or disengaging each element such as a planetary gear mechanism. Of course, it can also be applied to devices.

B) Embodiment An embodiment in which the present invention is applied to an automatic continuously variable transmission for a vehicle will be described below with reference to the drawings.

First, the outline of the present automatic continuously variable transmission will be explained with reference to FIG. 3. The present automatic continuously variable transmission A includes a belt type continuously variable transmission 31, a single planetary gear mechanism 40, a transfer device 80. Output member 7 consisting of reduction gear device 71 etc.
0 and a forward/reverse switching device 3 consisting of a dual planetary gear mechanism A, and a starting device 100 consisting of a fluid coupling 101, a centrifugal lock-up clutch 102, and a slip clutch 103.

The planetary gear mechanism 40 has a ring gear 4
0R is interlocked with the secondary shaft 33 of the continuously variable transmission 31, the carrier 40C is interlocked with the output member 70, and the sun gear 40S is connected via a transfer device 80 to a row one-way clutch F and a low coast system that constitute a locking means. It is connected to the reverse brake B1 and also to the input shaft 60 via the high clutch C2.

Further, in the dual planetary gear mechanism 3, the sun gear 3S is connected to the input shaft 60, and the carrier 3C is connected to the primary shaft 32 of the continuously variable transmission 31 and connected to the input shaft 60 via the forward clutch C1,
It is also connected to ring gear 3R or reverse brake B2.

Based on the above configuration, each clutch, brake, and one-way clutch in the present automatic continuously variable transmission A operate as shown in FIG. 4 at each position. Note that * indicates that the lock-up clutch 102 can be operated appropriately by centrifugal force.

To explain in detail, in low speed mode L in D range,
In addition to the forward clutch C1 being connected, the row one-way clutch F is activated. In this state, the rotation of the engine crankshaft is transmitted to the human power shaft 60 via the link-up clutch 102 and the slip clutch 103 or via the fluid coupling 101, and further directly transmitted to the sun gear 3S of the dual planetary gear device 3. At the same time, it is transmitted to the carrier 3C via the forward clutch C1. Therefore, the dual planetary gear mechanism 3 rotates integrally with the input shaft 60, and the forward rotation is transferred to the belt type continuously variable transmission 3.
The rotation is transmitted to the primary shaft 32 of the single planetary gear 40, and the rotation, which is appropriately changed in speed by the continuously variable transmission 31, is transmitted from the secondary shaft 33 to the ring gear 40R of the single planetary gear device 40. On the other hand, in this state, the sun gear 40S, which is a reaction force support element that receives reaction force, is stopped by the row one-way clutch F via the transfer device 80, and therefore the rotation of the ring gear 40R is taken out from the carrier 40C as decelerated rotation. , and further reduction gear device 7
1, etc., to the axle shaft 73.

Furthermore, in high-speed mode H in the D range, the high clutch C2 is connected in addition to the forward clutch C1. In this state, in the same manner as described above, the forward rotation that has been appropriately shifted by the continuously variable transmission 31 is taken out from the secondary shaft 33 and transferred to the ring gear 40 of the single planetary gear device 40.
input to R. Meanwhile, at the same time, the rotation of the input shaft 60 is transmitted to the sun gear 40S of the single planetary gear mechanism 40 via the high clutch C2 and the transfer device 80, whereby the torques of the ring gear 40R and the sun gear 40S are combined in the planetary gear mechanism 40. The signal is output from the carrier 40C. At this time, sun gear 4
Since the rotation that resists the reaction force is transmitted to 08 via the transfer device 80, torque circulation does not occur, and
A predetermined positive torque is transmitted via the transfer device 80. Then, the combined torque from the carrier 4°C is transmitted to the axle shaft 73 via the reduction gear device 71, etc.
transmitted to.

In addition, in the operation in the D range, it is free when reverse torque is applied (during engine braking) based on the one-way clutch F, but in the S range, in addition to the low one-way clutch F, the low coast reverse brake B1 is activated.
operates and transmits power even when reverse torque is applied.

Further, 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 reversely rotated by the belt-type continuously variable transmission 3 from the carrier 3C based on the ring gear 3R being fixed by the dual planetary gear mechanism 3.
1 is input. On the other hand, based on the operation of the low coast reverse brake B1, the single planetary gear device 40
The sun gear 408 is fixed, so the reverse rotation from the continuously variable transmission 31 is decelerated by the planetary gear mechanism 40 and taken out to the output member 70.

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

This continuously variable transmission A has a transmission case 49 that is divided into three parts, and an input shaft 60 and a primary shaft 32 of the continuously variable transmission 31 are rotatably supported on the same axis by the case 49. In addition to forming the axis,
Secondary shaft 33 and gear shaft 7 of continuously variable transmission 31
0a is coaxially and rotatably supported to constitute a second shaft.

Further, on the first shaft, a starting device 100, an operating section 50 consisting of a forward clutch C1, a high clutch C2, a low coast reverse brake B1, a reverse brake B2, and a row one-way clutch F, and a forward/reverse switching device are configured. A dual planetary gear mechanism 3 and a hydraulic pump 61 are disposed, and a single planetary gear mechanism 40 is disposed on the second shaft.

The starting device 100 includes a fluid coupling 101, a lock-up clutch 102 consisting of a centrifugal clutch, and a slip clutch 103. And slip clutch 103
is a cam mechanism 105 that generates an axial force corresponding to the load torque.
It has a cam machine'! fI1105 presses the clutch plate and disc of the slip clutch 103.
This increases the torque capacity of the slip clutch 103 in response to an increase in load torque.

Further, a protrusion 49a protrudes from the case 49 on the engine side of the input shaft 60, and an input sprocket 81 of the transfer device 80 is supported by the protrusion 49a via a bearing. Furthermore, the hub portion 81a of the sprocket 81 is connected to the case protrusion 49a via a one-way clutch F, and the sprocket 81
The input shaft 60 is connected to the inner circumferential surface of the flange extending radially outward from the flange via a high clutch C2 consisting of a multi-disc clutch, and the input shaft 60 is connected to the flange extending from the outer circumferential surface to the case 49. A low coast reverse brake B1 consisting of a multi-disc brake is interposed between the two.

Further, a sun gear 3S (see FIG. 3) of the dual planetary gear mechanism 3 is spline-coupled to the tip of the input shaft 60, and a flange extends in the outer diameter direction. In addition, the tip of the input shaft 60 is connected to the belt type continuously variable transmission device 3.
1 primary shaft 32 is fitted through a bushing,
The carriers 3C are aligned and splined to the shaft 32. Further, the carrier 3C supports a first pinion 3P1 and a second pinion 3P2, and a connecting member 6.7 extends in the outer diameter direction,
A forward clutch C1 consisting of a multi-plate clutch is interposed between the inner diameter side of the connecting member 6.7 and the outer diameter side of the flange 60a (FIG. 1) from the input shaft 60. Further, a reverse brake B2 consisting of a multi-disc brake is interposed between the outer peripheral side of the support member fixing the ring gear 3R and the case 49. A frictional engagement device actiniator unit 11 is disposed in the operating section 50 between the low coast reverse brake B1 and high clutch C2 and the reverse brake B2 and forward clutch C1.

, and the actuator unit 1 for the frictional engagement device.
1, as shown in FIG.
1b has a forward/reverse switching device motor 2 (not shown) and a low/high speed mode switching device motor 1 spaced apart from each other by a predetermined interval in the circumferential direction. These motors 1 and 2 are commutator motors,
The motor 1 is composed of a rotating magnetic field motor such as a step motor, an electric motor such as a servo motor, and an ultrasonic motor, and is provided with holding means such as an electromagnetic brake to hold the motor at a predetermined rotational position. 2 is the control unit C
It is configured to rotate and stop based on control signals issued from the controller.

The output gear 1a of the electric motor 1 is a counter gear 5.
It is connected to the shaft 30 via 5a and 55b,
A gear 30a is fixed to the shaft 30 and is also connected from another electric motor 2 (not shown) to a shaft 34 having a gear 34a. Furthermore, the actuator lla for the forward/reverse switching device and the actuator llb for the low/high speed mode switching device are clutches CI and C2, respectively.
Connecting members 6.7 for operation are arranged back-to-back and are each provided with a ball screw mechanism 15.16 having a female threaded portion 9.10 and a male threaded portion 12.13. Both ball screw mechanisms 15.1
The female threaded parts 9 and 10 of 6 are held in a case 49 so as not to be rotatable or axially movable, and a large number of disc springs 19 whose axial movements are prevented by a snap ring 59 are provided in the middle part thereof. , 20 are arranged extending left and right. A connecting member 6 for the clutch C1 is in contact with the tip of the disc spring 19 on the left side, that is, on the forward/reverse switching device side.
Further, the connecting member 7 for the clutch C2 is in contact with the tip of the disc spring 20 on the right side, that is, on the side of the low-high-speed mode switching device.

Furthermore, the inner diameter side ends of these connecting members 6.7 are connected to ball bearings 21.22, and these bearings are rotatably supported by the input shaft 60 via needle bearings, and each of them is connected to a ball bearing 21.22 for clutch operation. It is in contact with the disc springs 23 and 24. In addition, the disc spring 23.24
are supported at their intermediate portions by the support ends of the support members 26 and 27, respectively, and in a natural state where no force is applied from the connection member 6.7, the disc spring 23 on the forward/reverse switching device side operates the forward clutch C1. The high clutch C2 is biased to be connected, and the disc spring 24 on the low/high speed mode switching device side is biased to connect the high clutch C2.

In addition, the connection members 6 and 7 are connected to each other by these disc springs 23 and 24.
The biasing force of the return circumferential spring 19.20 located on the outer diameter side of the ball screw device is set to be large, so that the return circumferential spring 19,2 is
In the no-load state (home position) where no thrust force is acting on the forward clutch C, the return circumferential springs 19 and 20 overcome the engagement disc springs 23 and 24, and the forward clutch C
1 and high clutch C2 are held in a released state.

On the other hand, the gears 34a and 30a are attached to the male screw portions 12.13, which are the movable portions of the ball screw mechanism 15.16, respectively.
Gears 28, 29 that mesh with the gears 28, 29 are fixed, and connecting members 4, 8, 8, 7 are connected to the inner diameter side of the gears via ball bearings 17, 22. The connecting member 4.8 has protrusions 4a, 8a extending parallel to the axis toward the reverse brake B2, low coast and reverse brake B1, respectively, and these protrusions 4a.

8a are based on the axial movement of the externally threaded portions 12, 13, respectively, the brakes B2.8a. The brake can be locked by contacting the disc springs 14 and 18 of Bl. That is, the connecting member 4 engages the forward clutch C1 via the connecting member 6 by moving axially in one direction, and engages the reverse brake B2 by moving axially in the other direction. 8 engages the high clutch C2 via the connecting member 7 by moving in the axial direction in one direction, and engages the low coast and reverse brake B1 by moving in the axial direction in the other direction.

In addition, when the electric motor 1.2 is in the home position, the male threaded portion 12.13 is in the return position and the circumferential spring 19.20 is in the return position, and the protrusions 4a, 8a of the connecting member 4.8 are used for brake operation. Therefore, the forward/reverse switching device 3 is in a neutral position N where both the forward clutch C1 and the reverse brake B2 are released, and the low/high speed mode switching device 5 is in a high/high state. Both the clutch C2 and the low coast reverse brake B1 are in a released state, and the row one-way clutch F is in a low speed mode position in which it is activated. The electric motor 1.2 is also equipped with electromagnetic brakes that hold the motor in place, these electromagnetic brakes releasing the brakes when the current is turned off and releasing the brakes when the current is turned on. When the electric motors are de-energized, ie when the engine is not rotating, the electric motors 1, 2 are in their home position.

On the other hand, the continuously variable transmission 31, as shown in FIG. It consists of sheaves 35b and 36b. Further, the belt 37 includes a large number of metal pieces, and these pieces contact both the primary and secondary pulleys 35 and 36 in a lubricated state to transmit torque. Further, the pressure regulating cam mechanism 39 includes a fixed side cam portion 39a which is spline connected to the primary shaft 32 and whose axial movement is restricted by a flange portion, and a fixed side cam portion 39a which is spline connected to the fixed sheave 35a and has a disc spring. It consists of a movable cam part 39b that is pressed into contact with the movable cam part 39b, and a roller that is interposed between both cam parts, and applies an axial force corresponding to the transmitted torque to the fixed sheave 35b. The boss portion of the fixed sheave 35a extends toward the movable sheave 35b, and its inner circumferential surface fits into the primary shaft 32, and its outer circumferential surface has multiple rows of ball spline mechanisms (linear ball bearing links). ) 66 movable sheave 3
The boss portion 5b is supported so as to be movable only in the axial direction.

That is, the movable sheave 35b is fitted into the fixed sheave boss portion only through the balls without receiving any sliding resistance. Further, a ball screw device 42 is disposed at the back of the movable sheave 35b, and the ball screw device 42 is composed of a male screw portion, a female screw portion, and balls, and is of a circulette type in which the balls are circulated in a return passage. Become. In addition, 50 in the figure is an adjustment member.

Further, an automatic centering mechanism 62 is fixed to the female threaded portion of the ball screw device 42. Furthermore, primary shaft 3
A flange portion 67 is fixed to the distal end of 2 by screw connection, and an automatic centering mechanism 53 is connected to the flange portion. On the other hand, the fixed sheave 36a of the secondary pulley 36 is connected to the case 49 integrally with the secondary shaft 33.
The movable sheave 36b is rotatably supported by the movable sheave 36b.
A ball screw mechanism 43 and the like are disposed on the back side of the main body as well as on the primary side.

An electric motor 45 for speed change operation is fixed outside the case 49, and the electric motor 45 is
Similar to the electric motor in the operating section 50 described above, it has an electromagnetic brake 145 that can hold the motor in a predetermined position when the motor is not energized. The output gear of the motor 45 transmits power via the reduction gear 143 to the torque transmission device 63 that interlocks both of the ball screw devices described above.

The gears of the torque transmitting device 63 and the deceleration bag W143 are spur gears or helical gears, and are capable of reversible transmission and highly efficient power transmission.

Further, 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 the flange portion 46 of the secondary shaft 33 of the belt type continuously variable transmission 31. Further, the gear shaft 70a has a sprocket 82 integrated with the sun gear 40S.
is rotatably supported, and furthermore, on the gear shaft 70a,
Carrier 40 rotatably supports pinion 40P
C is fixed. Furthermore, the sun gear 4 on the second shaft
A silent chain 83 is wound between the sprocket 82 integrated with the 0S and the sprocket 81 supported by the row one-way clutch F, and these sprockets and chains connect the transfer device 80.
It consists of Further, the gear shaft 70a is a gear 71a.
are integrally configured to constitute the output member 70, and the gear 71a meshes 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, so that the reduction gear device 7
1. Furthermore, left and right front axle shafts 73 extend from the differential device 75.

The operation of this embodiment will now be explained.

In the operation unit 50, when the engine is stopped, that is, when the ignition switch is in the OFF position and the electric motors 1 and 2 are in a de-energized state, the electromagnetic brake is in a released state and the female screw portions 9 of the ball screw mechanisms 15 and 16 are in a released state. .10 is in a state in which no thrust force is applied to the disc springs 19, 14 and 20.18. Therefore, the forward/reverse switching device 3 is in the neutral position, and in this state, the biasing force of the return circumferential spring 19 overcomes the biasing force of the actuating disc spring 23.
The forward clutch C1 is in a released state, the protrusion 4a of the connecting member 4 does not come into contact with the disc spring 14, and the reverse brake B2 is also in a released state. Similarly, the low/high speed mode switching device 5 overcomes the biasing force of the return peripheral spring 20 or the biasing force of the actuating disc spring 24, and the high clutch C1
is in the released state, and the connecting member 8 is in its protrusion 8a.
does not come into contact with the disc spring 18, the low coast stall reverse brake B1 is in the released state, and the row one-way clutch F
It is in the low speed mode L state of the D range in which only the motor is in operation.

When the engine is started in this state, the electric motor 1.2 remains de-energized and the starter motor rotates the engine. Even if the input shaft 6o rotates through the fluid coupling based on the rotation of the engine, the forward/reverse switching device 3 is in a neutral state, and no power is transmitted to the continuously variable transmission 31, and the forward/reverse switching device 3 is in a neutral state. No power is transmitted from clutch C2 to transfer device 780, and therefore output member 70 of automatic continuously variable transmission 31 does not rotate. Furthermore, the rotation of the engine crankshaft is transmitted to the input shaft 60 via the fluid coupling 101 when the vehicle is started, and thereafter via the centrifugal lock-up clutch 102 and the slip clutch 103. The rotation of the input shaft 60 is changed to forward or reverse rotation by switching the forward/reverse switching device 3 through the operation of the forward clutch C1 or reverse brake B2 based on the actuator lla for the forward/reverse switching device. Fixed side cam part 39a of
transmitted to.

That is, when the shift lever is operated to the D (or S) range and the electric motor 2 for the forward/reverse switching device is rotated in one direction by a signal from the control unit C based on the operation, the gears 34a, 28
The male threaded portion 12 of the ball screw mechanism 15 rotates via. Then, the male threaded portion 12 is fixed to the female threaded portion 9.
1 and moves to the right in FIG. 1, so that the male threaded portion 12 abuts one of the connecting members 6 (via the other connecting member 4) and engages the return peripheral spring 19 and the actuating spring 19. The connecting member 6 is moved to the right against the difference between the disc springs 23.

When the predetermined position is reached, the actuating disc spring 23 begins to act on the forward clutch C1, and after that, the actuating disc spring 23 applies an engaging force to the clutch C1, so that the external threaded portion 12 returns to the peripheral spring 19. It moves due to a large thrust force that resists. Further, when the male threaded portion 12 moves in one direction, the clutch C1 is fully engaged and the return circumferential spring 19
This results in an overshoot condition that resists the predetermined characteristics of . In the D range (and S range), the electric motor 2
When the forward clutch C1 is engaged, the electromagnetic brake is turned on and held in this state. Note that when returning from the D range to the neutral range N, the electromagnetic brake is released and the electric motor 2 rotates in the opposite direction in accordance with the disk spring 19.

Furthermore, when the shift lever is operated to the reverse (R) range, the electric motor 2 (not shown) for the forward/reverse switching device rotates in the other direction from the neutral position ylN, which is the home position, by a signal from the control unit C based on the operation. Then, the male threaded portion 12 of the ball screw mechanism 15 moves to the left in FIG. 1, and the protruding portion 4a of the connecting member 4 contacts and compresses the disc spring 14 of the reverse brake B2. The connecting member 4 then moves further and engages the reverse brake B2.

In the R range, the electromagnetic brake of the electric motor 2 is operated while the reverse brake B2 is engaged, and the electric motor 2 is maintained in this state. Note that when the R range is returned to the neutral range N, the electromagnetic brake is released and the electric motor 2 is returned to the home position.

During the above-mentioned operation, since the connecting members 4 and 6 are connected to the male threaded portion 12 via the ball bearing 17, the protrusion 4a of the connecting member 4 comes into contact with the disc spring 14 and locks the reverse brake B2. Even when the other end of the connecting member 4 is brought into contact with the connecting member 6 to engage the forward clutch C1, the connecting member 4.6 and the male threaded portion 12 can freely rotate relative to each other. No wear occurs between the connecting member 4.6 and the male threaded portion 12, and the connecting member 4 can smoothly contact the protruding portion 4a with the disc spring 14 to lock the brake B2. The opposite side of the protruding portion 4a contacts the connecting member 6 to smoothly engage the clutch C1.

Further, when the shift lever is in the D range and the vehicle is in a low speed state, the electric motor 1 for the low/high speed mode switching device is in the home position, and the high clutch C2 and low coast reverse brake B1 are both in the released state. Yes, only the row one-way clutch F is in operation. When the vehicle reaches a predetermined high speed state, the electric motor 1 rotates in one direction in response to a signal from the control unit C, and connects the male threaded portion 13 of the ball screw device 16 (via the other connecting member 8) to one of the connections. The connecting member 7 is brought into contact with the member 7 and moved to the left in FIG. 1 against the difference between the return circumferential spring 20 and the actuating disk spring 24. Then, the actuating disc spring 24 acts on the high clutch C2 and engages the clutch C2. When the clutch C1 is fully engaged, the electromagnetic brake is turned on to hold the electric motor 1 in the position, and the input shaft 6
High speed mode H in which rotation of 0 is transmitted to the output member 70 by the belt type continuously variable transmission 31 and the transfer device 80
becomes. In addition, when the vehicle is in a low speed state or an accelerated state,
The electromagnetic clutch is turned off and the electric motor 1 is released, and the electric motor 1 rotates in the opposite direction and returns to the home position.

Further, when the shift lever is operated to the R range or the S range, the electric motor 1 for the low/high speed switching device rotates in the other direction from the home position, moves the male threaded portion 13 to the right in FIG. The protrusion 8a of 8 is brought into contact with the disc spring 18 of the low coast reverse brake B1, and the brake B1 is engaged. Then, with the brake B1 completely locked, the electromagnetic brake is turned on to hold the electric motor 1. Note that when the shift lever is in the S range and the vehicle reaches a predetermined high speed state, the electric motor 1 releases the electromagnetic brake and rotates in the opposite direction, releases the low coast reverse brake B1, and then shifts the high clutch. Engage C1.

During the above-mentioned operation, since the connecting member 8.7 is connected to the male threaded portion 13 via the ball bearing 22, the protrusion 8a of the connecting member 8 comes into contact with the disc spring 18, causing the low coast reverse brake B1 Even when locking the high clutch C2, the other end of the connecting member 8 is brought into contact with the connecting member 7.
Even when the connecting member 6 and the male threaded portion 13 are engaged, since the connecting member 6 and the male threaded portion 13 can freely rotate relative to each other, there is no wear between the connecting member 6 and the male threaded portion 13, and the connecting member 8 The protrusion 8a can smoothly contact the disc spring 18 to lock the brake B1, and the protrusion 8a
The opposite side can be brought into contact with the connecting member 7 to smoothly engage the clutch C1.

(g) As described in detail of the invention, according to the present invention, there is provided a torque generation mechanism (2) (or 1) that converts electrical energy into torque, and a thrust force generation mechanism (15) that converts torque into thrust force.
) (or 16) and the connecting means (4, 6) (or 8.7)
The connecting means is connected to the thrust force generating mechanism (15) (or 1) via the rolling bearing (17) (or 22).
Since it is connected to the movable part (12) (or 13) of 6), it has a simple configuration and can be directly and responsively controlled by electric signals from the control part (C), (4, 6) (or 87) and the male thread part (12
) (or 13) can be freely rotated to reliably prevent frictional resistance from occurring between them, thereby preventing wear and improving the durability of the device. By reducing the load on the torque generator fiJ (2) (or 1), the device can be configured compactly without requiring a large-capacity motor, and it is a highly reliable friction device that does not cause operational delays. It can be used as an actuator for a combination device.

Further, the thrust force generation mechanism (15) (or 16) includes a female screw portion (9) (or 10) that is fixed to the fixing member (49) in the axial direction and rotational direction, and a torque generation mechanism (
2) (or 1) and a male threaded part (12) (or 13) interlocked via a gear (34a) (or 30a), and the male threaded part is connected to the female threaded part. When the movable part is screwed together and moves in the axial direction,
It is possible to convert the force into a thrust force with an increase in force, and the friction engagement device can be easily and reliably operated simply by controlling the torque generating mechanism, and the structure of the device can be simplified.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an actuator for a frictional engagement device according to the present invention, FIG. 2 is a sectional view showing the entire continuously variable transmission, FIG. 3 is a schematic diagram thereof, and FIG. FIG. 6 is a diagram showing the operation of the elements. FIG. 5 is a sectional view showing an actuator for a frictional engagement device, which is the basis of the present invention. 1.2... Torque generation mechanism (electric motor) 3.5...
・Power transmission device (forward/reverse switching device, low/high speed mode switching device) 4.8... Connecting means (brake connecting member) 6,7... Connecting means (clutch connecting member) 9.10... Female thread part 11a, ll
b... Actuator for friction engagement device (actuator for forward/reverse switching device, actuator for low/high speed mode switching device), 12.13... Movable part (male thread part), 15.16... Thrust force generation Mechanism (ball screw mechanism) 17.22...Bearing (rolling bearing) 19.20...Returning spring means, 23.24...Spring means, 34a, 30a.
...Gear, 49...Fixing member (transmission case) Bl, B2. C1, C2...Frictional engagement device (low coast reverse brake, reverse brake, forward clutch, high clutch)
C...control unit (C). Figure 3

Claims (1)

[Scope of Claims] 1. An actuator that controls at least two frictional engagement devices interposed in a power transmission device using electrical signals from a control unit, the torque generating mechanism converting electrical energy into torque; a thrust force generation mechanism that converts the torque generated by the torque generation mechanism into thrust force; and a thrust force generation mechanism that is connected to a movable part of the thrust force generation mechanism and moves in the axial direction to operate the at least two frictional engagement devices. An actuator for a friction engagement device, comprising: a connecting means, and the connecting means is connected to a movable part of the thrust force generating mechanism via a rolling bearing. 2. The thrust force generation mechanism includes a ball screw mechanism having a female screw portion that is fixed to a fixed member in the axial direction and rotational direction, and a male screw portion that is interlocked with the torque generation mechanism via a gear. 2. The actuator for a frictional engagement device according to claim 1, wherein the male threaded portion is screwed into the female threaded portion to constitute the movable portion that moves in the axial direction. 3. The frictional engagement device actuator is an actuator for a forward/reverse switching device having a reverse brake and a forward clutch, and the connecting means includes a brake connecting member and a clutch connecting member, and the brake connecting member The actuator for a friction engagement device according to claim 1, wherein the clutch is integrally provided with a race of the rolling bearing, and the clutch connecting member is in contact with the race. 4. Spring means for holding the clutch in an engaged state is interposed between the forward clutch and the clutch connecting member, and the clutch connecting member has a strong urging force that opposes the spring means. The actuator for a frictional engagement device according to claim 3, wherein a return spring means is activated. 5. The actuator for a frictional engagement device is an actuator for a low-high speed mode switching device having a low brake and a high clutch, and the connecting means includes a connecting member for a brake and a connecting member for a clutch, and the connecting member for the brake The actuator for a friction engagement device according to claim 1, wherein the member is integrally provided with a race of the rolling bearing, and the clutch connecting member is in contact with the race. 6. A spring means for holding the clutch in an engaged state is interposed between the high clutch and the connecting member, and a returning member having a strong biasing force opposing the spring means on the clutch connecting member. The actuator for a frictional engagement device according to claim 5, wherein the actuator is actuated by a spring means. 7. The actuator for a forward/reverse switching device according to claim 4 and the actuator for a low/high speed mode switching device according to claim 6 are arranged adjacently with the fixed sides of the return spring means facing each other. , actuator unit.