JPS62297564A - Automatic transmission employing toroidal continuously variable transmission - Google Patents

Abstract

PURPOSE:To block an engine from starting when a drive stage or a reverse stage is being selected by coupling between an input shaft and an output shaft through a toroidal continuously variable transmission and first and second power transmission systems associated respectively with first and second clutches. CONSTITUTION:When a starting clutch 4 is disconnected under a condition shifted to D-range, a vehicle backs and the driving force of a drive wheel 32 is transmitted through an output shaft 3 to an intermediate shaft 2. Consequently, when the intermediate shaft 2 is rotated reversely, a oneway clutch 27 functions to block the reverse rotation of the intermediate shaft 2. If an engine 5 stable at this time because of an abrupt increase of load, the control oil pressure drops to zero so as to disconnect a hydraulically functionable output side clutch 25 thus interrupting a power transmission system between the output shaft 3 and a second power transmission system. Consequently, a shift lever is made operationable so as to enable the shifting from D-range to N-range where the engine can be started. When a vehicle is driven, the oneway clutch 27 can be unlocked automatically.

Description

Detailed Description of the Invention 3. Detailed Description of the Invention [Field of Industrial Application] The present invention relates to an automatic transmission using a toroidal continuously variable transmission applied to vehicles such as automobiles.

[Conventional technology]

An example of a conventional toroidal continuously variable transmission is the one described in Japanese Patent Application Laid-Open No. 58-54262. When the toroidal continuously variable transmission is used as an automatic transmission for a car and a starting clutch is interposed between the engine's drive shaft and the input shaft of the toroidal continuously variable transmission, the forward/reverse switching gear moves forward. If the vehicle moves backwards when the starting clutch is disengaged with the gear shifted to reverse gear, or if the vehicle moves forward when the starting clutch is disengaged with the forward/reverse gear shifted to reverse gear, the drive wheel will When force is input, the input/output disk of the toroidal type continuously variable transmission is reversed, and as a result, there is a problem in that the hydraulic speed change control mechanism becomes uncontrollable.

In order to prevent the above problems, conventionally a one-way clutch is interposed between the starting clutch and the axle shaft,
The operation of this one-way clutch was designed to prevent the human output disc from reversing.

[Problems with conventional technology]

However, in this case, if the engine stalls with the one-way clutch locked due to the forward/reverse switching gear reversing as the car moves, the switching gear will not come out and the shift lever will be moved to the D (drive) range or R.
(Reverse) Range to N to Neutral) Range or P
(Parking) You will not be able to switch to the range. Generally, automatic transmissions for automobiles are designed so that the engine cannot be started unless it is in the N or P range in order to ensure safety when starting.
The problem with the device provided with the one-way clutch is that the engine cannot be restarted.

This invention was made in view of the problems of the conventional technology, and it is possible that when the starting clutch is disengaged with the forward/reverse switching mechanism shifted to the forward gear, the vehicle may move backwards.
Alternatively, if the vehicle moves forward when the starting clutch is disengaged with the forward/reverse switching mechanism shifted to reverse, the clutch connected between the drive wheels and the toroidal continuously variable transmission is disengaged. The above-mentioned problems are solved by preventing the toroidal continuously variable transmission from reversing and by making the forward/reverse switching mechanism movable from the forward gear or the reverse gear to another position where the engine can be started. The purpose is

[Failure to solve the problem]

In order to solve the above problems, the present invention connects an input shaft and a drive shaft of a traveling drive device via a starting clutch, and connects an output shaft connected to the drive shaft with a toroidal shaft. A first power transmission system having a continuously variable transmission and a first clutch is connected to a second power transmission system having a forward/reverse switching mechanism and a second clutch, and the toroidal continuously variable transmission A one-way clutch is provided to prevent reversal of the output side of the engine, and at least when forward gear or reverse gear is selected by the forward/reverse switching mechanism, the engine is prevented from starting, and by disengaging the starting clutch, the vehicle is When the one-way clutch is locked and the engine is stopped by moving in a direction opposite to the selection direction, the forward/reverse switching mechanism can be switched from the forward gear or the reverse gear to another position where the engine can be started. The present invention is characterized by providing a control device that selectively controls the first clutch and the second clutch.

[Effect]

Therefore, in this invention, when the vehicle moves backward because the starting clutch is disengaged while the forward gear is selected, or because the vehicle moves forward because the starting clutch is disengaged while the reverse gear is selected, When the one-way clutch locks and the engine stops, the first clutch prevents the toroidal continuously variable transmission from reversing and connects the drive wheels and the toroidal continuously variable transmission. The second clutch is selectively controlled to interrupt the power transmission system, and the forward/reverse switching mechanism is movable from the forward gear or the reverse gear to another position where the engine can be started, thereby restarting the engine. possible.

〔Example〕

Hereinafter, the present invention will be explained based on the attached drawings.

FIG. 1 shows one embodiment of the present invention, and is a schematic explanatory diagram applied to a front engine front wheel drive vehicle.

First, to explain the configuration, in the figure, 1 is an input shaft, 2 is an intermediate shaft, and 3 is an output shaft. They are each rotatably supported.

A drive shaft 6 of an engine 5, which is an example of a traveling drive device, is connected intermittently to one end of the input shaft 1 in the axial direction via a starting clutch 4. A toroidal drive gear 7 is fixed to the toroidal drive gear 7, and further,
An input end switching section A is provided on the other side in the coaxial direction. The toroidal drive gear 7 is always in mesh with the toroidal manual gear 8 of the toroidal continuously variable transmission B provided on the intermediate shaft 2.

The toroidal continuously variable transmission B includes a loading cam 9 that is rotatably supported by the intermediate shaft 2 and has the toroidal manual gear 8 integrally formed on its outer periphery, and an input disk 10 that is rotatably supported by the coaxial shaft 2. And this human power disk 10
and a plurality of loading rollers 11 interposed between circumferentially continuous wavy cam surfaces formed on opposing end surfaces of the loading cam 9, an output disk 12 fixed to the same shaft 2, and the output disk 12 and input disk 1
It consists of a pair of power rollers 13 and 14 interposed between the rollers 13 and 14. Opposing end surfaces of the input disk 10 and the output disk 12 are each formed into a toroidal surface so as to have a semicircular shape when viewed in an axial cross section, and the power roller 13, 14 is arranged so as to be freely tiltable, and both power rollers 1
3.degree. 14 is connected to both disks 10.12.

Further, the input side switching section A is connected to the forward gear 15 and the reverse gear 16, which are rotatably supported by the input shaft 1, and which is movably interposed between the two gears 15 and 16 in the axial direction. It is comprised of a sleeve 17 that is always in mesh with the reverse gear 16 and can be selectively engaged with the reverse gear 16, and a shift fork 18 for moving this sleeve 17 in the axial direction. Interposed between the forward gear 15 and the input shaft 1 is an input side clutch 19 as a second clutch consisting of, for example, a wet multi-disc clutch operated by hydraulic pressure. The input side clutch 19 consists of a drive plate 19a that rotates together with the input shaft 1 and a friction plate 19b that rotates together with the forward gear 15, and is turned on and off by hydraulic pressure supplied from the hydraulic device 40.
FF controlled.

Reference numeral 41 denotes a control device for driving and controlling the hydraulic device 40, and includes, for example, a microcomputer having a human output interface circuit, an arithmetic processing unit, a storage device, etc., and controls output from the control device 41. Based on the signal, the hydraulic device 40 applies hydraulic pressure to the input side clutch 19 and the output side clutch 25, which will be described later.

The microcomputer of the control device 41 includes, for example, a vehicle speed sensor 42 that detects the rotation speed of the output shaft of a transmission and outputs a vehicle speed signal corresponding to the vehicle speed, and an engine that detects the rotation speed of the engine 5 and indicates the driving state. An engine rotation speed sensor 43 that outputs a rotation speed signal, a throttle opening sensor 44 that detects the opening of a throttle valve and outputs a throttle opening signal corresponding to the throttle opening, and detects a shift position of a transmission. A shift position sensor 45 that outputs a shift position signal corresponding to the shift position is connected to the shift position sensor 45, and the control device 41 performs control based on these vehicle speed signals, engine rotation speed signals, throttle opening signals, and position signals. Output a signal.

Further, the input side switching section A is configured to operate in conjunction with an output side switching section C provided on the output shaft 3.

This output side switching section C includes a forward gear 20 and a reverse gear 21 rotatably supported by the output shaft 3, and both gears 20, 21.
A sleeve 22 is interposed so as to be movable in the axial direction, is moved together with the sleeve 17, is selectively engaged with one of the gears, and is integral with the input shaft 1 in the rotational direction; Shift fork 23 for moving to
It is composed of. The forward gear 20 is always in mesh with the direct input end forward gear 15, and the reverse gear 21 is an intermediate gear (not shown) (this gear is used to reverse the direction of rotation during forward movement). It is always in mesh with the input side reverse gear 16 via.

Further, a clutch manual gear 24 is rotatably supported on the output shaft 3, and this clutch input gear 24 and the output shaft 3
An output side clutch 25 consisting of a wet type multi-disc clutch similar to the input end clutch 19 is interposed between the input end clutch 19 and the input end clutch 19. This output side clutch 25 includes a drive plate 25a that rotates integrally with the output shaft 3, and a clutch input gear 24.
and a friction plate 25b that rotates together with the hydraulic pressure device 40.
N/OFF controlled.

Further, a toroidal output gear 26 that rotates integrally with the intermediate shaft 2 is always engaged with the clutch input gear 24.

The driving force of the engine 5 is transferred to the output shaft 3 to the intermediate shaft 2.
A one-way clutch 27 is provided that can transmit torque to the engine side, but cannot transmit torque input from the opposite output shaft 3 to the engine side. This prevents the gear transmission B from reversing. Furthermore, an output gear 28 is fixed to the output shaft 3, and a differential manual gear 29 is always meshed with the output gear 28. A differential gear 30 and an axle shaft 31 are interlocked with the differential input gear 29. The torque transmitted to the output shaft 3 is transmitted to the front wheels 32, which are the drive shaft 32, through the drive shaft 32.

The toroidal drive gear 7, the toroidal continuously variable transmission B, the intermediate shaft 2, the toroidal output gear 26,
The clutch input gear 24 and the output side clutch 25 constitute a first power transmission system through which power passes through the toroidal section, and the second clutch 19, the input side switching section A, and the output side switching section C and the intermediate gear constitute a second power transmission system in which power does not pass through the toroidal section. Further, the input end switching section A, the output side switching section C, and the intermediate gear constitute a forward/backward switching mechanism.

Next, the effect will be explained.

Now, in order to start the vehicle, when the ignition key switch (not shown) is turned on to drive the engine and the control device 41 is activated, a vehicle speed signal from the vehicle speed sensor 42 and an engine speed signal from the engine speed sensor 43 are output. A throttle opening signal from the throttle opening sensor 44 and a shift position signal from the shift position sensor 45 are supplied to the control device 41.

From this state, in order to move the vehicle forward, the input side shift fork 18 and the output side shift fork 23 which are linked to the shift lever (not shown) are operated, and the input side sleeve 17 and the input end forward gear 15 are moved. The output side sleeve 22 is connected to the output side forward gear 2 while ensuring engagement of the output side sleeve 22.
0, a shift position signal representing a state of being shifted to the forward gear is input to the control device 41, and the control device 41 outputs a control signal to the hydraulic device 40. As a result, the hydraulic device 40 outputs hydraulic pressure to actuate (ON) only the output side clutch 25, so the input side clutch 19 remains inactive (OFF), while the output side clutch 25 In the actuated state, the clutch input gear 24 and the output shaft 3 become integral in the rotational direction.

From this state, when the driver connects the starting clutch 4 to connect the drive shaft 6 of the engine 5 and the input shaft 1, the driving force generated by the engine 5 is transmitted to the input shaft 1 via the starting clutch 4. The human power 4Il111 is transmitted to the intermediate shaft 2 via the toroidal drive gear 7, toroidal manual gear 8, loading cam 9, loading roller 11, input disk 10, power roller 13° 14 and output disk 12, and then further to the output side. Since the clutch 25 is engaged, the toroidal output gear 26 integrated with the intermediate shaft 2 is connected to the clutch input gear 24 and the output side clutch 25.
is transmitted to the output shaft 3 via. At the same time, the drive plate 19 of the input side clutch 19 is integrated with the input shaft l.
a and the forward gears 15 and 20 also rotate, but since the input end clutch 19 is disengaged, no rotational force is transmitted to these rotating parts.

Therefore, the output shaft 3 is rotationally driven by the torque transmitted via the toroidal continuously variable transmission B, and the torque is transmitted from the output gear 28 to the differential input gear 29, the differential gear 30, and the axle shift 31 to the driving wheels. The signal is transmitted to the front wheels 32, which causes the vehicle to start moving forward. Then, tilt the power rollers 13 and 14,
If the distance from the center of contact with the human-powered disc 10 to the axial center line of the intermediate shaft 2 is longer than the distance from the center of contact with the output disc 12 to the axial center line of the intermediate shaft 2, the vehicle speed will increase depending on the amount of tilting. or rise. Such a shift state is generally referred to as the D (drive) range.

Thereafter, when the vehicle speed reaches a preset reference vehicle speed value, the control signal from the control device 41 changes to disengage the output side clutch 25, and then the input side clutch I9 is connected. Then, while torque transmission from the clutch manual gear 24 to the output shaft 3 becomes impossible, torque is transmitted from the drive plate 19a of the input side clutch 19, which rotates integrally with the input shaft 1, to the friction plate 19b. The signal is transmitted from the forward gear 15 of the input side switching section A, which is integrated with the forward gear 15, to the forward gear 20 of the output side switching section C, which meshes with the forward gear 15, and is further transmitted from the sleeve 22, which meshes with the forward gear 20, to the output shaft 3. Ru. Such a speed change state is a so-called OD (overdrive) range.

Next, when moving the vehicle backwards, move the shift lever to R (
Shift to reverse) range and shift fork 18.2
Through the operation of 3, each sleeve 1 of input/output switching parts A and C
7.22 mesh with the reverse gear 16°21, respectively. Then, a position signal representing the reverse gear is input to the control device 41, which causes the control device 41 to switch the hydraulic device 40.
The input side clutch 19 is disengaged and the output side clutch 25 is connected.

From this state, when the driver connects the starting clutch 4 to connect the drive shaft 6 of the engine 5 and the input shaft 1, the input shaft 1
The driving force transmitted from the input side clutch 19 to the input side switching section is transmitted to the reverse gear 16, and this reverse gear 16
The signal is transmitted from the reverse gear 21 of the output side switching section C via the intermediate gear, and is transmitted from the sleeve 22 meshing with the reverse gear 21 to the output shaft 3. As a result, the output shaft 3 is rotated through the second power transmission system in a direction opposite to that when moving forward, and this rotation is transmitted to the drive wheels 32, causing the vehicle to move backward.

The above is the normal operation of the automatic transmission according to the present invention.

In such an automatic transmission, when the vehicle moves backward by disengaging the starting clutch 4 while shifting to the D range, the driving force input from the drive wheels 32 is transferred to the axle shaft 31, differential gear 30, differential input gear 29, and It is transmitted to the output shaft 3 via the output gear 28 , and from the output shaft 3 to the intermediate shaft 2 via the output side clutch 25 , clutch input gear 24 , and toroidal output gear 26 . Therefore, when the intermediate shaft 2 reverses, the one-way clutch 27 provided thereon operates to prevent the intermediate shaft 2 from reversing.

At this time, if the engine 5 stops due to a sudden load, the control oil pressure becomes zero and the hydraulically operated output side clutch 2
5 is cut, and the connection between the output shaft 3 and the second power transmission system is cut off. As a result, a free state in which power is not transmitted becomes available, and the shift lever can be operated, allowing a shift from the D range to the N range or P range, where the engine can be started.

Therefore, by shifting from the D range to the N range or the P range, the engine 5 can be restarted thereafter. Thereafter, when the vehicle is shifted to the D range again and the vehicle is advanced to 1); I as described above, the one-way clutch 27 is automatically unlocked.

Also, when shifting to R range, start clutch 4
When the vehicle moves forward by switching the switch, the driving force transmitted from the drive wheels 32 to the output shaft 3 is transferred from the reverse gear 21, sleeve 22 and intermediate gear of the output side switching section C to the reverse gear 16 of the input side switching section A, and the sleeve. I7, input end clutch 19, input shaft l, toroidal output gear 7, toroidal manual gear 8
, the loading cam 9, the input disc 10, the power rollers 13, 14 and the output disc 12 to the intermediate shaft 2, thereby causing the intermediate shaft 2 to reverse.

As a result, the one-way clutch 27 provided on the intermediate shaft 2 is operated to prevent the intermediate shaft 2 from rotating in reverse.

At this time, when the engine 5 similarly stops due to a sudden load, the control oil pressure becomes zero, the hydraulically operated input side clutch 19 is disengaged, and the connection between the output shaft 3 and the input shaft 1 is cut off. As a result, the power transmission system is in a free state where it does not transmit power, so the shift lever can be operated and the R
It becomes possible to shift from range to N range or P range.

Therefore, when the engine 5 is restarted after shifting from the R range to the N range or the P range, and then the vehicle is moved backward by shifting to the R range again, the one-way clutch 27 is automatically unlocked.

In this embodiment, when the one-way clutch 27 that receives the driving force input from the driving wheels 32 and prevents the toroidal continuously variable transmission B from reversing is locked and the engine is stopped, the driving wheels 32 and Toroidal continuously variable transmission B
Because the clutch that connects the
The reverse switching mechanism can now switch from the forward gear or the reverse gear to the N range or P range, a position where the engine can be started. Therefore, by shifting to the N range or the P range, the engine can be restarted. Therefore, even if the vehicle moves backward by disengaging the starting clutch 4 with the forward/reverse switching mechanism in the forward gear, or if the vehicle moves backward by disengaging the starting clutch 4 with the forward gear in the reverse gear. The toroidal input/output disk is not reversed, and even if the engine stalls, the engine can be restarted quickly.

In the above embodiments, an example in which an engine is used as the traveling drive device has been described, but the present invention is not limited to this, and it goes without saying that an electric motor or other power generating device can be used.

〔Effect of the invention〕

As explained above, according to the present invention, the vehicle moves backward because the starting clutch is disengaged while the forward gear is selected, or the vehicle moves backward because the starting clutch is disengaged while the reverse gear is selected. When the one-way clutch locks and the engine stops as a result of moving forward, the first clutch and the second clutch that connect the drive wheels and the toroidal continuously variable transmission are selectively controlled. The power transmission system is cut off to prevent the toroidal continuously variable transmission from reversing, and the forward/reverse switching mechanism is configured to be able to move from forward gear or reverse gear to another position where the engine can be started. Therefore, it is possible to reliably prevent the toroidal continuously variable transmission from reversing, and even when the engine stalls, it is possible to respond quickly, restart the engine immediately, and restart the vehicle smoothly. You can get the effect that you can.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing an embodiment of the present invention.

Claims (1)

[Claims] The input shaft and the drive shaft of the travel drive device are connected via a starting clutch, and a toroidal continuously variable transmission and a first clutch are provided between the output shaft connected to the drive wheels and the input shaft. A one-way clutch is provided, which is connected to the first power transmission system and a second power transmission system having a forward/reverse switching mechanism and a second clutch, and prevents reversal of the output side of the toroidal continuously variable transmission. , at least said forward
When forward gear or reverse gear is selected by the reverse gear shift mechanism, the engine is prevented from starting, and by disengaging the starting clutch, the vehicle moves in the opposite direction to the selected direction, the one-way clutch is locked, and the engine is stopped. A control device that selectively controls the first clutch and the second clutch so that the forward/reverse switching mechanism can be switched from the forward gear or the reverse gear to another position where the engine can be started when the engine stops. A transmission device using a toroidal continuously variable transmission.