JPS61140663A - V belt type stepless speed change gear - Google Patents

Abstract

PURPOSE:To prevent wrong functioning by driving a servomechanism comprising of two screws and their flanks under control made by a driver and a fluid pressure actuator. CONSTITUTION:In a V-belt type stepless speed change gear having servo- mechanisms 6, 7 and a cam mechanism 8, running is done at constant reduced speed and pressure by bringing a first screw 37 and a second screw 61 into contact with a second flank 102 without a ball 37a, and the speed is changed by causing the stroke of a movable flange 3B through driving means composed of an oil pressure servo 9A and a driver. Consequently the inserting pressure of the V-belt in changing the speed can be properly adjusted by controlling the pressure in the oil pressure servo, and quick speed change becomes possible. In addition, the buffer effect of the oil pressure servo can relieve the sudden action of the driver.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a continuously variable transmission with a cam mechanism using a V-belt.

[Prior Art] In general, a vehicle power transmission device 100, as shown in FIG. The mechanism 150, the input shaft 111 and output shaft 112 of the V-belt continuously variable transmission 140, the idler shaft 113 provided between the output shaft 112 and the differential mechanism 150, and the case 1 that houses these.
The belt type continuously variable transmission t11140 consists of an input shaft 111, an output shaft 112 arranged parallel to the input shaft 111, fixed flanges 103A and 104A, and The fixed flanges 103A, 10 are displaceable and the fixed flanges 103A, 10
Movable flange 103B rotates integrally with 4A.

104B, an input pulley 103 and an output pulley 104, and these input pulley 103 and output pulley 91.
04 and the input pulley 1.
An input side servo mechanism 106 includes a hydraulic servo 109A, which is a fluid pressure actuator that displaces the movable flange 103B of the output pulley 104 in the axial direction, and a hydraulic servo 109B, which is a fluid pressure actuator that displaces the movable flange 104B of the output pulley 104 in the axial direction. The output side servo mechanism 107 consists of an output side servo mechanism 107, and the change of the speed ratio (or reduction ratio) and the increase/decrease of the clamping force between the pulley and the V-belt 105 are performed only by hydraulic pressure.

[Problems to be Solved by the Invention] The V-belt type continuously variable transmission 140 having the above configuration generates high hydraulic pressure to ensure the torque transmission capacity of the V-belt 105 when running in the electric range speed ratio. The hydraulic pressure on the output side was balanced with the hydraulic pressure on the output side, and the movable flange stroke was fixed. Therefore, if the balance between the two was not stabilized, there was a risk of malfunction. Further, when the oil pressure decreases, there is a risk that the V-belt 105 may slip. Additionally, high oil pressure was constantly generated during driving, which was disadvantageous for transmission efficiency.

The object of the present invention is to provide an efficient and highly reliable V-belt type continuously variable transmission that prevents malfunctions and can run without hydraulic pressure.

[Means for Solving the Problems] The V-belt continuously variable transmission of the present invention includes an input shaft, an output shaft arranged parallel to the input shaft, a fixed flange, and an effective diameter for the fixed flange. an input pulley and an output pulley, each consisting of a movable flange that is movable in the axial direction and rotates integrally with the fixed flange; a V-belt that transmits power between the input and output pulley; and the input pulley. In a belt-type continuously variable transmission comprising an input side servo mechanism that displaces the movable flange of the output pulley in the axial direction, and an output side servo mechanism that displaces the movable flange of the output pulley in the axial direction, at least one of the servo mechanisms , a first screw formed on the movable flange or a member interlocking with the movable flange, and a second screw screwed into the first screw, the first screw and the second screw being connected to the ball. a first flank in contact through the ball, and a second flank in direct contact without the ball;
A drive element that displaces the movable flange in the axial direction by relative rotation between the screw and the second screw, a control means for the drive element that causes the movable flange to relatively rotate the drive element in the axial direction such that the movable flange has a reduced effective diameter, and a movable flange. Alternatively, it is composed of a fluid pressure actuator provided between a member that interlocks the movable flange and the driver, and a cam mechanism that makes the clamping force between the movable flange and the fixed flange and the V-belt proportional to the transmission torque of the V-belt. shall be.

[Operations and Effects of the Invention] With the above configuration, the V-belt type continuously variable transmission of the present invention has the following operations and effects.

When running in the electric range speed ratio, the first and second screws come in contact with each other at their second flanks without balls, resulting in an automatic tightening state, and the movable flange stroke is fixed, and the cam mechanism responds to the transmitted torque. to generate clamping force. This makes it possible to run with a stable foot speed ratio without applying hydraulic pressure.

When changing gears, the movable flange is stroked by a hydraulic servo, the first screw, the second screw, and a driving element, thereby changing the speed.

By applying pressure from the hydraulic servo to the side, the V-belt clamping force during gear shifting can be made appropriate, the torque capacity of the V-belt is improved, and the driving force of the drive element is also reduced, allowing for quick gear shifting.

In addition, the damping effect of the hydraulic servo can alleviate the sudden operation of the drive element, making stable gear changes possible.

In this way, efficiency is improved and reliability is improved.

[Example] Next, the V-belt type continuously variable transmission of the present invention will be explained based on the example shown in the drawings.

FIG. 1 shows a first embodiment of the V-belt type continuously variable transmission of the present invention.

1 is an input shaft of a V-belt type continuously variable transmission, 2 is an output shaft of the V-belt type endlessly variable transmission arranged parallel to the input shaft 1, 3 is an input pulley provided on the input shaft 1, and 4 is an input shaft of the V-belt type continuously variable transmission. An output pulley provided on the output shaft 2, 5 a V-belt that transmits power between the input pulley 3 and output pulley 4, 6 a servo mechanism that changes the effective diameter of the input pulley 3, 7 an effective diameter of the output pulley 4 A servo mechanism 8 is a cam mechanism provided on the input pulley 3.

The input shaft 1 has an axial oil passage 11 formed therein, and an annular plate-shaped member 18 connected to the outer periphery of the left end in the figure by welding or the like.
A cylindrical member 19 is provided which is fixed to the annular plate member 18 by spline fitting and a snap ring 19a, and the cylindrical member 19 is rotatably supported by the V-belt type continuously variable transmission case 10 by a bearing 14a. ing. Oil road 11
has radial oil passages 11a and llb.

In this embodiment, the output shaft 2 is formed integrally with a sleeve-shaped portion of a fixed flange, which will be described later, and has a radial oil passage 21a inside.
, 21b, an outer spline 22 and a tip screw 23, and bearings 24 and 25 to form a V-belt continuously variable transmission case 10.
is rotatably supported.

The input pulley 3 has one end (the right end in the drawing) rotatably supported by the V-belt type continuously variable transmission case 10 by a bearing 14, and the other end is supported by the V-belt by a bearing 14a via a cam race 82 and a cylindrical member 19. It is rotatably supported by a continuously variable transmission case 10, and the outer periphery of the other end is provided with screws 15, 7 Uta splines 16, and the radial oil passages 11a, 11.
a radial oil passage 31a formed at a position corresponding to b;
3tb and a sleeve-shaped portion 33 provided with a keyway 32;
A fixed flange 3A consisting of a sleeve-shaped portion 33 and a flange portion 35 integrally formed.

The sleeve-like portion 33 of the fixed flange 3 is fitted onto the sleeve-shaped portion 33 so as to be freely displaceable in the axial direction, and a key groove 36 corresponding to the key groove 32 of the fixed flange 3A is formed on the inner circumferential wall, and a ball 37a is formed on the outer circumferential wall. The first flank 1 that contacts through
01 and a second flank 102 that contacts without a ball on the slope opposite to the first flank 101. 38 and a flange portion 39 integrally formed with the hub portion 38.
, and a ball key 30 which is inserted into the keys @32 and 36, allows the fixed flange 3A and the movable flange 3B to be displaced in the axial direction, and rotates around the axis integrally.

The output pulley 4 has a keyway 41, an outer spline 42, and a screw 43 formed on the outer periphery, and a sleeve-shaped portion 44 formed integrally with the output shaft 2; A fixed flange 4^ consisting of a flange portion 45 and a sleeve-shaped portion 44 of the fixed flange 4A are fitted onto the outside so as to be freely displaceable in the axial direction, and a 4;-groove 450 corresponding to the key groove 41 is provided on the inner peripheral wall. , ball 4 on the outer wall
A first screw 46 is formed, consisting of a first flank 301 that contacts via 6a and a second flank 302 that contacts without a ball on the opposite slope of the first flank 301,
A sleeve-shaped hub portion 47 in which a radial oil passage 21c is formed.
A movable flange 4B consisting of a flange portion 48 formed integrally with the hub portion 47, and keys 41 and 45.
0, fixed flange 4A and movable flange 4B
It consists of a ball key 40 for integrally rotating with.

■The belt 5 comes into contact with the working surfaces of the V-shapes 1M3b and 4b formed by the fixed flanges 3A and 4A of the input pulley 3 and the output pulley 4, and the movable flanges 3B and 4B, respectively, to form a friction surface. Working surfaces 51 and 52 are provided on both sides.

The servo mechanism 6 of the input pulley 3 is screwed into the first screw 37 of the movable flange 3B of the input pulley 3, and the ball 37
A first flank 201 that contacts via a, and a second flank that contacts without a ball on the opposite slope of the first flank 201.
A second screw (drive screw) 61 consisting of a flank 202
is formed on the inner circumference, and one end 621 is a thrust bearing 6
A sleeve 62, which is a driver of a movable flange, is brought into contact with the other cam race 87 of the cam mechanism, which will be described later, through 5;
An eddy current downshift brake 63 is provided between the guide portion 262 of the sleeve 62 and the V-belt continuously variable transmission case 10 and brakes the sleeve 62, the movable flange 3B and the other end 623 of the sleeve 62. It consists of a hydraulic servo 9A which is a fluid pressure actuator provided between the two.

The hydraulic servo 9A has an axial side wall 91a and a radial side wall 92.
a and a wall 3a of a movable flange 3B.
3a, the radial side wall 92a, and the thrust bearing 94.
The hydraulic piston 95a is rotatably supported by the hydraulic piston 95a, and a return spring 96a for the hydraulic piston 95a.

The servo mechanism 7 of the output pulley 4 is connected to the movable flange 4B.
A first flank 401 that is threadedly engaged with the first screw 46 and makes contact via the ball 46a, and a second flank 402 that makes contact without the ball on the slope opposite to the first flank 401.
A sleeve 12, which is a driver, has a second screw 71 formed on its inner periphery, and a guide portion 272 of the sleeve 72.
and the V-belt continuously variable transmission case 10,
An eddy current type upshift brake 73 that brakes the sleeve 72 and a spline that fits with the outer spline 42 of the output shaft 2 are formed, and one surface on the movable flange 4B side is connected to the sleeve 72 via the thrust bearing 15.
The support ring 77 that supports the sleeve 72 in the axial direction, the other surface is locked with the nut 76 through the bearing 24, the movable flange 4B and the other end 723 of the sleeve 72 are in contact with the end surface 721 of the sleeve 72. It consists of a hydraulic nervo 9B which is a fluid pressure actuator provided in between.

The hydraulic servo 9B has an axial side wall 91b and a radial side wall 92.
cylinder 9 consisting of wall portion 4a of movable flange 4B
3b, radial side wall 92b and thrust bearing 94
The hydraulic piston 95b is rotatably supported by the hydraulic piston 95b, and a return spring 96b for the hydraulic piston 95b.

The cam 114i48 is supported in the axial direction by a nut 17 screwed into the screw 15 formed at the end of the sleeve-shaped portion 33, and also has an inner spline 81 spline-fitted with an outer spline 16 of the sleeve-shaped portion 33. The other cam race 87 is formed with a sleeve-shaped portion 33.
one cam race 82 that is slidable on the outer periphery of the cam race, and a tapered roller 88 that is interposed between these cam races;
a covering ring 89 of the roller 88, which covers the working surfaces 82A and 87A of the cam races 82 and 87;
sandwiched between the input shaft 1, the annular plate member 18, the cylindrical member 19, the cam race 82, the taper roller 88,
The pressing force for pressing the movable flange 3B in the right direction in the drawing is changed in accordance with the torque transmitted to the cam race 8T.

Next, the operation of this continuously variable transmission will be explained.

(a) When traveling at constant speed, all brakes 63 and 13 are released.

Torque is transmitted through the input shaft 1 → one cam race 82 of the force ram mechanism 8 → the taper roller 88 → the other cam race 87 → the input coupler 3 → ■ belt 5 → the output output boule 4
→This is done in the order of output shaft 2. At this time, the second flank 102 of the first screw 37 of the movable flange 3B of the input coupler 3 comes into contact with the second flank 202 of the second screw 61 of the sleeve 62, and the stroke of the movable flange 3B becomes fixed. The second flank 302 of the first screw 46 of the movable flange 4B of the output pulley 4 comes into contact with the second flank 402 of the second screw 71 of the sleeve 12, and the movable flange 4B
The stroke of is also fixed. In this state, the cam mechanism 8 generates an axial force proportional to the transmitted torque, and this axial force is applied to the movable flange 3B via the sleeve 62. The clamping force of the V-belt 5 acts due to the contact pressure with the working surface of ^, and on the other hand, the V-belt 5 also acts on the output pulley 4.
A clamping force is applied through the surface pressure between the working surface of the belt 50 and the working surfaces of the movable flange 4B and the fixed flange 4A.

In this way, a clamping force proportional to the transmission torque of the V-belt 5 is generated, and the vehicle runs at a constant speed.

(b) Upshift is done by brake 73 and hydraulic servo 9
This is done by applying A and 9B.

The brake 73 applies a braking force to the sleeve 72 to rotate the movable flange 4B relative to the sleeve-shaped hub 47, thereby displacing the movable flange 4B in a direction that reduces the effective diameter of the output pulley 4 (toward the right in the figure). At the same time, when the ball screw is subjected to an axial load, the hydraulic servo 9A
When the relative rotation and stroke occur, a force is generated to spread the space between the movable flange 3B and the sleeve 62, and the sleeve 6
2 and the sleeve-shaped hub 38 of the movable flange 3B are rotated relative to each other, and the movable flange 3B is displaced in a direction that increases the effective diameter of the input pulley 3 (to the right in the figure). On the other hand, the belt clamping force (2) at this time is ensured by the force of the hydraulic servo 9A that pushes the space between the movable flange 3B and the sleeve 62 apart. The brake 73 is released when the reduction ratio reaches the set value of 11tIl.

(c) Downshift is done by brake 63 and hydraulic servo 9
A, 9B is applied.

The brake 63 applies a braking force to the sleeve 62 to rotate the movable flange 3B relative to the sleeve-shaped hub 38, thereby displacing the movable flange 3B in a direction that reduces the effective diameter of the input pulley 3 (to the left in the figure). At the same time, when the ball screw is subjected to an axial load, the hydraulic servo 9B
Similarly to the relative rotation and stroke, the movable flange 4B
A force is generated to spread the gap between the sleeve 72 and the sleeve 72, relatively rotating the sleeve 72 and the sleeve-shaped hub 41 of the movable flange 4B, and displacing the movable flange 4B in the direction of increasing the effective diameter of the output pulley 4 (to the left in the figure). let On the other hand, the belt clamping force (1) at this time is ensured by the force of the hydraulic servo 9B that pushes apart the space between the movable flange 4B and the sleeve 72. When the reduction ratio reaches the serial control setting value, the brake 63 is released.

FIG. 2 shows a second embodiment of the V-belt type continuously variable transmission of the present invention.

This embodiment is based on the outer circumference 6 of the sleeve 62.12 of the first embodiment.
24.724, a spring guide part 1625.725 is provided between the brakes 63.73, the cover ring 89 of the cam mechanism 8 is extended radially outward to form a spring guide part 89a, and the outer periphery of the support ring 11 is A spring guide member 77a is provided in the spring guide member 625.
The torsion coil spring 64A is placed between the spring guide portion 89a and the torsion coil spring 74A between the spring guide member 725 and the spring guide member 77a, and the sleeves 62 and 72 are rotated relative to each other. 62.72 are arranged so as to make an extension stroke, and at the end of the gear shift, the first screw 31.46 and the second screw 61.71 are securely brought into contact with the second flank 102.202.302.402. It is characterized by

FIG. 3 shows a third embodiment of the V-belt type continuously variable transmission of the present invention.

In this embodiment, the servo mechanism 6 of the input pulley 3 of the second embodiment
The hydraulic servo 9A is eliminated and a spring guide member 626 provided on the outer periphery of the movable flange 3B and the sleeve 62 is used.
A torsion coil spring 64A and a compression coil spring 64B having a rectangular cross section are arranged between the two to control the speed change.

The operation of this embodiment will be explained.

b) When running at low speed, it functions in the same way as the first embodiment.

O) Upshift is done by brake 73 and hydraulic servo 9B
This is done by applying

As in the first embodiment, the effective diameter of the output pulley 4 is reduced,
At the same time, the compression coil spring 64B and the torsion coil spring 64A move the movable flange 3B.
A force is generated to spread the gap between the sleeve 62 and the sleeve 62, causing the sleeve 62 and the sleeve-shaped hub 38 of the movable flange 3B to rotate relative to each other, displacing the movable flange 3B in a direction that increases the effective diameter of the input pulley 3, and reducing speed. When the ratio reaches the control set value, the brake 73 is released.

c) Downshift is done by brake 63 and hydraulic servo 9B
This is done by applying

As in the first embodiment, the brake 63 accumulates energy in the compression coil spring 64B and the torsion coil spring 64A while applying braking force to the sleeve 162 to reduce the effective diameter of the input pulley 3, and at the same time, the hydraulic servo 9B causes the output pulley to Increase the effective diameter of 4. When the reduction ratio reaches the control set value, the brake 63 is released.

This embodiment has the following effects: 1) On the input pulley 3 side, the required clamping force relative to the transmitted torque is large when the effective diameter of the belt is small, and vice versa. Since this relationship substantially matches the load generated by the spring, an appropriate belt clamping force can be obtained with these simple spring configurations.

2) Since only the pressure control of the hydraulic servo on the output pulley 4 side is required, the control circuit etc. are simplified.

FIG. 4 shows a fourth embodiment of the V-belt type continuously variable transmission of the present invention.

In this embodiment, the servo mechanism 6 of the input pulley 3 has a second screw 661 formed on the inner periphery, which is screwed into the first screw 337 of the movable flange 3B of the input pulley 3, and the end portion of the servo mechanism 6 has an annular guide portion. 268 and a sleeve 662 which is a driver of the movable flange 3B which is in contact with the other cam race 87 of the cam mechanism 8 via a thrust bearing 665, and a cylindrical member 265 fixed to the outer periphery 264 of the guide portion 266 of the sleeve 662. and a V-belt type continuously variable transmission case 10, an eddy current type downshift brake 663 that brakes the sleeve 662, and a fluid pressure actuator provided between the movable flange 3B and the guide part 266. It consists of a certain hydraulic servo 90A.

The hydraulic servo 90Δ is connected to the outer peripheral wall 991a of the sleeve 662.
and an inner peripheral wall 992a of the guide portion 266, and one end 951a is a thrust bearing 952.
It includes a hydraulic piston 953a rotatably supported by the movable flange 3B via a, and a return spring 954a for the hydraulic piston 953a.

Further, the servo mechanism 7 of the output pulley 4 has a second screw 71 formed on the inner periphery to be screwed into the first screw 46 of the movable flange 4B of the output pulley 4, and the end thereof is connected to the annular guide portion 276.
and support ring 7 via thrust bearing 775.
A sleeve 772 that is a driver of the movable flange 4B that is in contact with the outer periphery 2 of the guide portion 276 of the sleeve 772
An eddy current upshift brake 773 is provided between the cylindrical member 275 fixed to the cylindrical member 74 and the V-belt continuously variable transmission case 10 to brake the sleeve 772, and an eddy current upshift brake 773 is provided between the movable flange 4B and the sleeve 772. It consists of a hydraulic servo 90B which is a hydraulic actuator provided.

The hydraulic servo 90B is connected to the outer peripheral wall 991b of the sleeve 772.
and an inner peripheral wall 992b of the guide portion 276, and one end 951b is a thrust bearing 952.
The hydraulic piston 953b is rotatably supported by the movable flange 4B via the hydraulic piston 953b, and a return spring 954b for the hydraulic screws 1 to 953b. Further, 1A indicates an input shaft, and 2A indicates an output shaft.

In this embodiment, a hydraulic servo is used as the fluid pressure actuator, but other types may be used.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a first embodiment of the V-belt continuously variable transmission of the present invention, and FIG. 2 is a cross-sectional view of a second embodiment of the V-belt continuously variable transmission of the present invention.
3 is a sectional view of the third embodiment of the V-belt continuously variable transmission of the present invention, and FIG. 4 is a sectional view of the fourth embodiment of the V-belt continuously variable transmission of the present invention. FIG. 5 is a sectional view of a power transmission device for a vehicle using a conventional V-belt type continuously variable transmission.

Claims (1)

[Claims] 1) An input shaft, an output shaft disposed parallel to the input shaft, a fixed flange, and the fixed flange, which is movable in the axial direction to change the effective diameter with respect to the fixed flange. An input pulley and an output pulley consisting of a movable flange that rotates integrally with the flange, a V-belt that transmits power between the input pulley and the output pulley, and an input side servo mechanism that displaces the movable flange of the input pulley in the axial direction. , an output side servo mechanism that displaces the movable flange of the output pulley in the axial direction, a clamping force between the movable flange and fixed flange provided on at least one of the input shaft or the output shaft, and the V belt, and the transmission torque of the V belt. In a belt-type continuously variable transmission comprising a cam mechanism proportional to the first and second screws have a first flank in contact through a ball and a second flank in direct contact without a ball; A drive element that displaces the movable flange in the axial direction by relative rotation between the screw and the second screw, a control means for the drive element that causes the movable flange to relatively rotate the drive element in the axial direction such that the movable flange has a reduced effective diameter, and a movable flange. Alternatively, a V-belt continuously variable transmission characterized by comprising a fluid pressure actuator provided between a member that interlocks a movable flange and a driver. 2) The V-belt according to claim 1, wherein at least one of the servo mechanisms has a torsion coil spring inserted between the movable flange or a member that interlocks the movable flange and the driver. Continuously variable transmission.