JPH11159596A - Automatic continuously variable transmission for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve restarting capability without the turning of a speed change mechanism into a top state even in the case of quick braking by providing a driving side shaft with a torque converter having starting function nearer an engine side than a driving side pulley, and providing an output shaft with a forward and backward movement changing over mechanism having a clutch function. SOLUTION: A transmission 2 is provided with a torque converter 10 arranged in the engine side end portion of a driving side shaft 6, and an output shaft, 48 is provided with a forward and backward movement changing over mechanism 52 having a clutch function. Since the torque converter having starting function nearer an input side than a speed change mechanism 12 is provided, and the forward and backward movement changing over mechanism 52 having the clutch function nearer an output side than the speed change mechanism 12 is provided, the speed change mechanism 12 is therefore not directly coupled with a driving shaft. Thus the speed change mechanism 12 is not kept in a top state in the case of quick braking or tire locking and restarting ability is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a continuously variable automatic transmission for a vehicle, and more particularly to a continuously variable automatic transmission for a vehicle having a forward / reverse switching mechanism.

[0002]

2. Description of the Related Art In a vehicle, a transmission is provided on a transmission path between an engine and driving wheels because the engine is not suitable for the same condition.

[0003] This transmission includes a drive-side fixed pulley piece fixed to a drive-side shaft disposed coaxially with an engine crankshaft, and a drive mounted in the drive-side shaft so as to be axially movable and non-rotatable. A driving pulley composed of a side movable pulley piece is provided, and the driven side fixed pulley piece fixed to a driven side shaft disposed in parallel with the driving side shaft and the driven side shaft are axially movable and non-rotatably mounted on the driven side shaft. A continuously variable automatic transmission for vehicles having a driven pulley including a driven movable pulley piece, a metal belt wound around a driving pulley and a driven pulley, and an output shaft provided on a driven shaft. is there.

In this continuously variable automatic transmission for a vehicle, a forward / reverse switching mechanism and a starting clutch are provided on the input side of a transmission mechanism including a driving pulley, a driven pulley, and a belt. There is a mechanism in which a forward / reverse switching mechanism is provided on the input side of the mechanism and a start clutch is provided on the output side of the transmission mechanism, or a forward / backward switching mechanism and a start clutch are provided on the output side of the transmission mechanism.

[0005] Such a continuously variable automatic transmission for a vehicle is disclosed, for example, in Japanese Patent Application Laid-Open No. Hei 9-126286. According to this publication, the driving force of an engine is input in parallel to two sets of belt-type continuously variable transmission mechanisms from a common input shaft, and a differential gear is transmitted from an output shaft of each belt-type continuously variable transmission mechanism. The transmission is transmitted from the ring gear to the wheel side via each side gear of the above, and at this time, even if there is a rotation difference between each output shaft of each belt type continuously variable transmission mechanism, the rotation difference is absorbed by a differential device, As a result, even if there is a speed ratio error between the belt-type continuously variable transmission mechanisms, this is mechanically permitted, and precise shift control of each belt-type continuously variable transmission mechanism is not required, and the control system is complicated. It is to avoid the conversion.

[0006]

However, conventionally, in a continuously variable automatic transmission for a vehicle, when a forward / reverse switching mechanism and a starting clutch are provided on the input side of the speed change mechanism, the speed change mechanism and the drive wheels are not provided. Is directly connected, so the gearshift mechanism remains in the top state during sudden braking or tire locking,
In addition to the inconvenience of low restartability, the inconvenience that when the engine is stalled with the transmission mechanism in the top state, the starting clutch is located on the input side of the transmission mechanism, making it difficult to restart. there were.

Also, a case where the forward / reverse switching mechanism is provided on the input side of the transmission mechanism and the starting clutch is provided on the output side of the transmission mechanism, and a case where the forward / backward switching mechanism and the starting clutch are provided on the output side of the transmission mechanism. However, since the forward / reverse switching mechanism and the starting clutch are independently separated from each other, the configuration is complicated and the space is disadvantageous.

[0008]

SUMMARY OF THE INVENTION In order to eliminate the above-mentioned disadvantages, the present invention provides a drive-side fixed pulley piece fixed to a drive-side shaft disposed coaxially with an engine crankshaft. A driven-side fixed pulley fixed to a driven-side shaft disposed in parallel with the drive-side shaft, the drive-side pulley comprising a drive-side movable pulley piece mounted on the drive-side shaft so as to be axially movable and non-rotatably mounted. A driven pulley comprising a piece and a driven side movable pulley piece mounted axially movably and non-rotatably on the driven side shaft is provided, and a belt is wound around the drive side pulley and the driven side pulley, In the continuously variable automatic transmission for a vehicle having an output shaft provided on the driven side shaft, a torque converter provided with a start function on the engine side relative to the drive side pulley is provided on the drive side shaft, and the output shaft is provided on the output shaft. Clutch function Characterized in that a reverse switching mechanism before provided.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention provides a torque converter having a start function on the input side of a transmission mechanism including a driving pulley, a driven pulley and a belt, and a clutch function on the output side of the transmission mechanism. Since the forward and reverse switching mechanism provided is provided, the transmission mechanism and the drive wheels are not directly connected,
The transmission mechanism does not go to the top state even during sudden braking, improving the re-startability.Also, even if an engine stall occurs when the transmission mechanism is in the top state, the transmission mechanism is always in the idle state, The vehicle can be easily restarted, and can be smoothly started and creeped by the torque converter.

Further, since the forward / reverse switching mechanism has a clutch function, it is not necessary to provide the forward / reverse switching mechanism and the starting clutch independently of each other. This simplifies the configuration and is advantageous in terms of space. Can be.

[0011]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing an embodiment of the present invention; 1 to 4 show an embodiment of the present invention. In FIG. 1, reference numeral 2 denotes a continuously variable automatic transmission for a vehicle (hereinafter referred to as a “transmission”) mounted on a vehicle;
Is a transmission case. The transmission case 4 includes first to first
It comprises three case parts 4-1 to 4-3 and a case cover 4-4.

The transmission 2 includes a driving side shaft 6 disposed coaxially with an engine crankshaft (not shown), a driven side shaft 8 disposed in parallel with the driving side shaft 6, Side shaft 6
Converter 1 arranged at the engine side end portion
0, and a speed change mechanism 12 disposed on the drive-side shaft 6 and the driven-side shaft 8.

A torque converter 10 provided at an end portion of the drive shaft 6 on the engine side has a starting function (lock-up function), and includes a pump impeller 14 and a turbine runner 1.
6 and the stator 18 are integrally formed.
The pump impeller 14 includes a drive plate (not shown).
And is directly connected to the crankshaft through the shaft. The turbine liner 16 is provided so as to be spline-fitted to the drive side shaft 6. The stator 18 is assembled to the transmission case 4 via a one-way clutch 20, and functions as a torque converter (torque converter) at the time of starting, accelerating, and climbing a hill, and as a fluid clutch (fluid coupling) at a constant running time. It works.

A drive pulley 22 constituting the transmission mechanism 12 is provided at an end of the drive shaft 6 remote from the engine.

The drive-side pulley 22 includes a drive-side fixed pulley piece 24 fixed to the drive-side shaft 6 and a drive-side movable pulley piece 2 mounted on the drive-side shaft 6 so as to be axially movable and non-rotatable.
6 On the back side of the driving side movable pulley piece 6,
A drive side housing 30 forming a drive side hydraulic chamber 28 is mounted.

The driving side shaft 6 has a driving side pulley 22.
An oil pump 32 is provided between the motor and the torque converter 10.

The driven side shaft 8 is provided with a driven side pulley 34 constituting the transmission mechanism 12 together with the driving side pulley 22.

The driven pulley 34 includes a driven-side fixed pulley piece 36 fixed to the driven-side shaft 8 and a driven-side movable pulley piece 3 mounted on the driven-side shaft 8 so as to be axially movable and non-rotatable.
8 A driven housing 42 forming a driven hydraulic chamber 40 is provided on the rear surface of the driven pulley piece 38.
Is installed. The driven hydraulic chamber 40 includes:
An adjustment spring 44 for pressing the driven-side movable pulley piece 38 toward the driven-side fixed pulley piece 36 is provided.

A metal belt 46 constituting the transmission mechanism 12 is wound around the driving pulley 22 and the driven pulley 34.

Therefore, the speed change mechanism 12 includes the drive pulley 2
2, a driven pulley 34 and a belt 46.

As a result, the transmission mechanism 12 is controlled by a hydraulic control mechanism (not shown). The transmission pulley 22 controls the speed change state, and the driven pulley 34 holds the clamping force of the belt 46. Is what you do.

The driven shaft 8 is provided with an output shaft 48.

A hub 50 is provided on the output shaft 48 by spline fitting.

The output shaft 48 is provided with a forward / reverse switching mechanism 52 having a clutch function.

The forward / reverse switching mechanism 52 includes a forward clutch 56 comprising a wet multi-plate start clutch 54 mounted on the hub 50, and a reverse clutch comprising a planetary gear 58 and a wet multi-plate reverse brake 60. 62
And are integrally combined.

The starting clutch 54 is mounted on a clutch support 64 of the hub 50.

The planetary gear 58 is, as shown in FIG.
The sun gear 66 is spline-fitted to the output shaft 48, the internal gear 68 is fixed to the output shaft 48, and three pinion components 70 revolve between the sun gear 66 and the internal gear 68. The pinion component 70 is configured by connecting a sun gear pinion 72 meshing with the sun gear 66 and an internal gear side pinion 74 smaller than the sun gear side pinion 72 and meshing with the internal gear 68 with a carrier 76. .

The brake joint 7 between the outer peripheral surface of the internal gear 68 and the case wall 4-2a of the second case 4-2.
A reverse brake 60 is interposed between the eight.

On the output side of the forward / reverse switching mechanism 52, primary and secondary reduction mechanisms 80 and 82 are provided as reduction mechanisms having a predetermined reduction ratio. A differential section 84 is provided on the output side of the primary and secondary reduction mechanisms 80 and 82.

That is, the first rotation shaft 86 of the primary reduction mechanism 80 is disposed coaxially with the driven shaft 8. This first
A first reduction gear 88 is fixedly provided on the rotating shaft 86, and a connecting housing 90 is joined and fixedly provided. This connection housing 90 is
A communication portion 92 arranged substantially parallel to the first rotating shaft 86 is located on the outer peripheral surface of the starting clutch 54 and is provided so as to be fitted to the carrier 76 of the planetary gear 58.

In parallel with the first rotation shaft 86, the second rotation shaft 94
Are arranged. The second rotating shaft 94 is provided with a second one-side reduction gear 96 meshing with the first reduction gear 88 by spline fitting.
8 is fixedly provided.

The second fixed reduction gear 98 has a differential portion 8
A ring gear 102 fixed to the fourth differential case 100 is provided in mesh therewith.

Next, the operation of this embodiment will be described.

In starting operation of the vehicle, as shown in FIG. 1, the driving force from the engine is applied to the driving shaft 6 and the transmission mechanism 1.
2 and the driven side shaft 8 to reach the hub 50 spline-fitted to the output shaft 48, and the starting clutch 54 frictionally engages the hub 50 with the connecting portion 92 of the coupling housing 90, It is transmitted to the primary reduction mechanism 80 side.

On the other hand, FIG.
As shown in FIG. 4, when the internal gear 68 fixed to the output shaft 48 and the brake joint 78 are frictionally engaged and fixed by the reverse brake 60, the pinion is formed by the sun gear 66 spline-fitted to the output shaft 48. Component 7
0 is transmitted to the internal gear 67 and the output shaft 48
, The pinion structure 70 revolves,
The rotation of the carrier 76 causes the carrier 76 to rotate.
The driving force is transmitted to the connecting portion 92 of the coupling housing 90 fitted to the first speed reduction mechanism 8.
It is transmitted to the 0 side.

As a result, the torque converter 10 having a starting function is provided on the input side of the transmission mechanism 12, and the forward / reverse switching mechanism 52 having the clutch function is provided on the output side of the transmission mechanism 12. Since the speed change mechanism 12 and the drive wheels are not directly connected, the speed change mechanism 12 does not remain in the top state at the time of sudden braking or tire lock, and the re-startability is improved.
Even if an engine stall occurs when the engine 2 is in the top state, the start clutch 54 is present on the output side of the transmission mechanism 12, so that the transmission mechanism 12 is always in an idle state, and restarting can be facilitated.

When the vehicle is started, the torque converter 10 is used, so that the vehicle can be started smoothly and creep can be provided.

Further, the forward / reverse switching mechanism 52 has a clutch function, and the forward clutch 56 and the reverse clutch 62
Is integrated, there is no need to separately provide the forward / reverse switching mechanism 52 and the clutch, and the configuration can be simplified and the space can be advantageously improved.

Further, since the primary and secondary reduction mechanisms 80 and 82 are provided on the output side (rear) of the forward / reverse switching mechanism 52, the reduction ratio can be changed to a predetermined value, and an appropriate reduction ratio can be easily obtained. Obtainable.

[0040]

As is apparent from the above detailed description, according to the present invention, the drive shaft is provided with a torque converter having a start function on the engine side of the drive pulley,
By providing a forward / reverse switching mechanism with a clutch function on the output shaft, the transmission mechanism will not be in the top state even during sudden braking, etc., improving re-startability and the transmission mechanism is in the top state. Therefore, even if an engine stall occurs, the transmission mechanism is always in the idle state, so that the vehicle can be easily restarted, and the torque converter can provide smooth start and creep.

Further, since the forward / reverse switching mechanism has a clutch function, it is not necessary to provide the forward / reverse switching mechanism and the starting clutch independently of each other, which can simplify the configuration and can be advantageous in terms of space.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a transmission during forward movement.

FIG. 2 is a cross-sectional view of the transmission during reverse travel.

FIG. 3 is an enlarged sectional view of a forward / reverse switching mechanism.

FIG. 4 is a diagram illustrating an operation state of a planetary gear at the time of reverse travel.

[Explanation of symbols]

 Reference Signs List 2 transmission 6 drive side shaft 8 driven side shaft 10 torque converter 12 transmission mechanism 22 drive side pulley 34 driven side pulley 46 belt 48 output shaft 50 hub 52 forward / reverse switching mechanism 56 forward clutch section 62 reverse clutch section 80 primary deceleration Mechanism 82 Secondary speed reduction mechanism 84 Differential part

Claims (3)

[Claims] 1. A drive-side fixed pulley piece fixed to a drive-side shaft arranged coaxially with a crankshaft of an engine, and a drive-side movable pulley mounted on the drive-side shaft so as to be axially movable and non-rotatable. A driven-side fixed pulley piece fixed to a driven-side shaft provided in parallel with the drive-side shaft, and a driven member mounted axially movably and non-rotatably on the driven-side shaft. In the continuously variable automatic transmission for a vehicle, a driven pulley comprising a side movable pulley piece is provided, a belt is wound around the drive side pulley and the driven side pulley, and an output shaft is provided on the driven side shaft. A vehicle provided with a torque converter provided with a start function on the drive side shaft on the engine side of the drive side pulley, and a forward / reverse switching mechanism provided with a clutch function on the output shaft; Stepless automatic change Speed machine. 2. The forward / reverse switching mechanism includes a combination of a forward clutch unit including a wet forward clutch and a reverse clutch unit including a planetary gear and a wet reverse brake. A continuously variable automatic transmission for vehicles according to claim 1. 3. The continuously variable automatic transmission according to claim 1, wherein a speed reduction mechanism having a predetermined reduction ratio is provided on an output side of the forward / reverse switching mechanism.