JP2002089645A - Toroidal type continuously variable transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a small-sized, lightweight and low-cost continuously variable transmission of toroidal type of such a structure that three trunnions and power rollers are installed in one cavity. SOLUTION: A trunnion 7c is displaced by a pair of single acting hydraulic actuators 73a and 73b. Two other trunnions 7a and 7b are displaced by respective double acting hydraulic actuators 60a and 60b. These actuators 60a and 60b have a section of an elliptic shape and their operations can be confirmed, if acceptable or not, prior to installation in a casing 5a.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The toroidal type continuously variable transmission according to the present invention is used, for example, as a transmission unit of a transmission for an automobile or as a transmission for various industrial machines.

[0002]

2. Description of the Related Art The use of a toroidal type continuously variable transmission as schematically shown in FIGS. 5 and 6 has been studied as a transmission for an automobile, and has been partially implemented. This toroidal type continuously variable transmission is called a half toroidal type, and supports an input side disk 2 concentrically with an input shaft 1 as disclosed in, for example, Japanese Utility Model Laid-Open Publication No. Sho 62-71465. An output disk 4 is fixed to an end of an output shaft 3 arranged concentrically with the shaft 1. Inside a casing 5 (see FIG. 8 to be described later) in which the toroidal type continuously variable transmission is housed, there are pivots 6, 6 which are twisted with respect to the input shaft 1 and the output shaft 3.
The trunnions 7, 7 swinging around the center are provided.

Each of the trunnions 7, 7 is provided with a pair of pivots 6, 6 on the outer surfaces of both ends thereof, concentric with each other and with each of the trunnions 7, 7.
The central axis of each of these pivots 6, 6 is
Does not intersect with the center axis of each of these discs 2,
4 is at a torsional position that is perpendicular or nearly perpendicular to the direction of the central axis. Also, each of the trunnions 7,
At the center of 7, the base half of the displacement shafts 8, 8 is supported, and by swinging the trunnions 7, 7 about the pivots 6, 6, the inclination angles of the displacement shafts 8, 8 are adjusted. Adjustable. Power rollers 9 and 9 are provided around the first half of the displacement shafts 8 and 8 supported by the trunnions 7 and 7, respectively.
Is rotatably supported. These power rollers 9, 9 are sandwiched between the inner surfaces 2a, 4a of the input and output disks 2, 4, respectively.

The inner surfaces 2a and 4a of the input and output disks 2 and 4 facing each other are obtained by rotating a circular arc centered on the pivot 6 or a curve close to such circular arc. It has an arc-shaped concave surface. Then, the peripheral surfaces 9a, 9a of the power rollers 9, 9 formed on the spherical convex surfaces are brought into contact with the inner side surfaces 2a, 4a. In addition, a loading cam device 10 is provided between the input shaft 1 and the input disk 2, and the loading cam device 10 is used to load the input disk 2.
, While being elastically pressed toward the output-side disk 4, can be rotationally driven.

When the toroidal-type continuously variable transmission configured as described above is used, the loading cam device 10 causes the input side disk 2 to move to the plurality of power rollers 9 with the rotation of the input shaft 1. Rotate while pressing. And
The rotation of the input disk 2 is transmitted to the output disk 4 via the plurality of power rollers 9, and the output shaft 3 fixed to the output disk 4 rotates.

When the rotational speed between the input shaft 1 and the output shaft 3 is changed, and when deceleration is first performed between the input shaft 1 and the output shaft 3, each of the trunnions 7, 7 and the peripheral surface 9 of each of the power rollers 9 and 9 described above.
As shown in FIG. 5, each of the displacement shafts 8 and 9a comes into contact with a portion of the inner surface 2a of the input disk 2 near the center and a portion of the inner surface 4a of the output disk 4 near the outer periphery. 8 is tilted.

On the other hand, in order to increase the speed, the trunnions 7, 7 are swung, and the power rollers 9, 9 are rotated.
As shown in FIG. 6, the peripheral surface 9a of the input side disk 2
Each of the displacement shafts 8 is inclined so as to abut against a portion of the inner side surface 2a near the outer periphery and a portion of the inner side surface 4a of the output side disk 4 near the center, respectively. Each of these displacement axes 8, 8
If the inclination angle is set between those in FIGS. 5 and 6, an intermediate speed ratio can be obtained between the input shaft 1 and the output shaft 3.

FIGS. 7 and 8 show Japanese Utility Model Application No. 63-6929.
3 shows a more specific toroidal-type continuously variable transmission described in Microfilm No. 3 (Japanese Utility Model Laid-Open No. 1-173552). Input disk 2 and output disk 4
Are rotatably supported around the input shaft 11 having a tubular shape. Further, a loading cam device 10 is provided between the end of the input shaft 11 and the input side disk 2. On the other hand, the output side disk 4 has the output gear 1
2 so that the output disk 4 and the output gear 12 rotate synchronously.

The pivots 6, 6 provided concentrically at both ends of the pair of trunnions 7, 7 swing and move in the axial direction (front and back directions in FIG. 7) on a pair of support plates 13, 13, which are support members. ,
(The left and right direction in FIG. 8). And
The base half of the displacement shafts 8, 8 is supported in the middle of each of the trunnions 7, 7. Each of these displacement shafts 8 and 8 makes the base half and the first half eccentric to each other. The base half of the trunnions 7 is rotatably supported in the middle of the trunnions 7, and the power rollers 9 are rotatably supported in the first half thereof.

The pair of displacement shafts 8, 8 are provided at positions opposite to the input shaft 11 by 180 degrees. or,
The directions in which the base half and the front half of each of the displacement shafts 8, 8 are eccentric are the same (the left and right opposite directions in FIG. 8) with respect to the rotation directions of the input side and output side disks 2, 4. .
Further, the eccentric direction is a direction substantially orthogonal to the direction in which the input shaft 11 is provided. Accordingly, the power rollers 9 are supported so as to be slightly displaceable in the direction in which the input shaft 11 is disposed.

A thrust ball bearing is provided between the outer surface of each of the power rollers 9 and 9 and the inner surface of the intermediate portion of each of the trunnions 7 and 7 in order from the outer surface of each of the power rollers 9 and 9. 14, 14 and thrust needle bearings 15, 1
5 are provided. Of these, thrust ball bearings 14, 1
4 allows the rotation of the power rollers 9 while supporting the load in the thrust direction applied to the power rollers 9. Further, each of the thrust needle bearings 15,
Reference numeral 15 denotes the first half of each of the displacement shafts 8 and 8 and the outer ring 16 while supporting the thrust load applied from the respective power rollers 9 and 9 to the outer rings 16 and 16 constituting the respective thrust ball bearings 14 and 14. , 16 are allowed to swing about the base half of each of the displacement shafts 8, 8. Further, each of the trunnions 7, 7 is provided with a hydraulic actuator 17, 1,
7, the pivots 6, 6 can be displaced in the axial direction.

In the case of the toroidal type continuously variable transmission configured as described above, the rotation of the input shaft 11 is transmitted to the input disk 2 via the loading cam device 10. And
The rotation of the input disk 2 is transmitted to the output disk 4 via a pair of power rollers 9, 9, and the rotation of the output disk 4 is extracted from the output gear 12.

When changing the rotational speed ratio between the input shaft 11 and the output gear 12, the above-mentioned actuators 17, 1
7, the pair of trunnions 7, 7 are respectively arranged in opposite directions, for example, the lower power roller 9 of FIG. 8 is on the right side of the figure, the upper power roller 9 of FIG. Displace each. As a result, the direction of the tangential force acting on the contact portions between the peripheral surfaces 9a, 9a of the power rollers 9, 9 and the inner surfaces 2a, 4a of the input disk 2 and the output disk 4 changes. I do. Then, with the change in the direction of the force, the trunnions 7, 7 swing in opposite directions about the pivots 6, 6 pivotally supported by the support plates 13, 13, respectively. As a result, as shown in FIGS. 5 and 6 described above, the contact positions between the peripheral surfaces 9a and 9a of the power rollers 9 and the inner surfaces 2a and 4a change, and the input shaft 11 The rotation speed ratio with the output gear 12 changes.

During power transmission by the toroidal type continuously variable transmission, the power rollers 9 are displaced in the axial direction of the input shaft 11 based on the elastic deformation of the components. Then, the respective displacement shafts 8 supporting the respective power rollers 9 slightly rotate about the respective base halves. As a result of this rotation, each of the thrust ball bearings 14, 1
4 and the outer surfaces of the outer races 16, 16 and the respective trunnions 7, 7
Relatively displaces with the inner surface. Since the thrust needle bearings 15, 15 exist between the outer surface and the inner surface, the force required for the relative displacement is small.

In the case of the toroidal type continuously variable transmission constructed and operated as described above, the input shaft 11 and the output gear 12 are used.
Is transmitted by two power rollers 9, 9. Therefore, the peripheral surface 9 of each power roller 9
a, 9a and the inner surface 2 of both the input and output disks 2, 4
a and 4a, the force per unit area transmitted becomes large, and the limit of transmittable power is relatively low. In view of such circumstances, it has been conventionally considered to increase the number of power rollers 9 in order to increase the power that can be transmitted by the toroidal-type continuously variable transmission.

As an example of a structure for increasing the number of power rollers 9 for such purpose, conventionally, three power rollers 9 between a pair of input side disk 2 and output side disk 4 are provided. 9 is disposed, and power is transmitted by the three power rollers 9, 9, for example, as disclosed in Japanese Unexamined Patent Application Publication No.
As described in JP-A-67-67, it has been conventionally known. In the case of the structure described in this publication, as shown in FIG. 9, support members, each of which is a support member and is bent at 120 degrees, are provided at three positions at equal intervals in the circumferential direction of the fixed frame 18. , 19 in the middle. The trunnions 7, 7 are supported between the adjacent support pieces 19, 19 so as to swing and be displaceable in the axial direction.

Each of the trunnions 7, 7 can be displaced in the axial direction of a pivot 6 provided concentrically at both ends by hydraulic actuators 17, 17, respectively. The hydraulic cylinders 20, 20 constituting the actuators 17, 17 are connected to the discharge port of a pump 22, which is a hydraulic source, via a control valve 21. The control valve 21 includes a sleeve 23 and a spool 24 that are each displaceable in the axial direction (the left-right direction in FIG. 9). Each of the actuators 17, 17 is of a double-acting type that generates an axial force in any direction with respect to the axial direction by switching the supply / discharge direction of the pressure oil.

When the inclination angle of the power rollers 9, 9 pivotally supported by the displacement shafts 8, 8 is changed to the respective trunnions 7, 7, the sleeve 23 is moved in the axial direction by the control motor 25 (FIG. 9). Left and right directions). As a result, the pressure oil discharged from the pump 22 is sent to each of the hydraulic cylinders 20, 20 through a hydraulic pipe. The drive pistons 26, 26 fitted on the hydraulic cylinders 20, 20 for displacing the trunnions 7, 7 in the axial direction of the pivot shaft are connected to the input side disk 2
And, it is displaced in the same direction with respect to the rotation direction of the output side disk 4 (see FIGS. With this displacement, the trunnions 7, 7 are displaced in the axial direction of the pivot 6, and
Swinging about the same as in the case of the structure shown in FIGS. In addition, each drive piston 2
With the displacement of the hydraulic cylinders 6, 26,
The hydraulic oil pushed out from the oil tank is returned to the oil reservoir 27 through a hydraulic pipe (not shown) also including the control valve 21.

On the other hand, the displacement of the drive piston 26 and the trunnion 7 connected to the drive piston 26 accompanying the feeding of the pressure oil are transmitted to the spool 24 via a precess cam 28 and a link 29, and the spool 24 is moved in the axial direction. To be displaced. As a result, with the drive piston 26 displaced by a predetermined amount, the flow path of the control valve 21 is closed, and the supply and discharge of pressure oil to and from the hydraulic cylinders 20 and 20 are stopped. Therefore, the amount of displacement of each of the trunnions 7, 7 in the axial direction is determined by the
3 only corresponds to the amount of displacement.

In the case of the conventional toroidal-type continuously variable transmission configured and operated as described above, the installation space for the actuators 17 and 17 increases, and the size of the apparatus increases. On the other hand, Japanese Patent Application Laid-Open No. 8-145134 describes a structure for reducing the installation space of the actuator by a structure as shown in FIGS. In the case of this conventional structure, the frame 3 fixed in the casing 5 (see FIG. 8) for accommodating the toroidal type continuously variable transmission in order to support the trunnion 7.
A hydraulic actuator 31 is provided in the area 0. The cross-sectional shape of the inner peripheral surface of the cylinder chamber 32 constituting the hydraulic actuator 31 and the outer peripheral surface of the drive piston 33 that is oil-tightly fitted in the cylinder chamber 32 has an elliptical shape as shown in FIG. The shape is an ellipse as shown in FIG.

The outer peripheral edge of a seal ring 34 mounted on the outer peripheral surface of the drive piston 33 is slidably contacted with the inner peripheral surface of the cylinder chamber 32 so that the inside of the cylinder chamber 32 is oil-tightly separated from each other. And a pair of hydraulic chambers 35a, 35b. When the trunnion 7 is displaced in the axial direction of the pivots 6, 6, pressure oil is supplied to and discharged from each of the hydraulic chambers 35 a, 35 b through a supply / discharge path (not shown).

A circular pipe 36 provided at the center of the driving piston 33 and a pivot 6 provided at an end of the trunnion 7 are provided.
A sleeve 37 also serving as a lock nut and a thrust rolling bearing 38a are provided in this order from the pivot 6 side. On the other hand, a bolt 39 for connecting and fixing the other end surface of the circular pipe portion 36 to the pivot shaft 6 is provided.
A thrust rolling bearing 38b is provided between the head and the head 40. Therefore, the bolt 39 and the pivot 6 and the trunnion 7 to which the ends of the bolt 39 are connected are rotatable with respect to the drive piston 33.

In the conventional toroidal-type continuously variable transmission configured as described above, in order to support a large thrust load applied to the trunnion 7, the capacity of the hydraulic actuator 31 is increased. Even if the cross-sectional areas of the chamber 32 and the drive piston 33 are increased, the diametrical dimension of the hydraulic actuator 31 can be partially reduced. As a result, the outer dimensions of the toroidal-type continuously variable transmission can be reduced, and the toroidal-type continuously variable transmission can be downsized.

[0024]

In the case of the conventional structure shown in FIGS. 10 to 11, the installation space for the hydraulic actuator 31 can be reduced to reduce the size and weight, but consideration is given to the case of actual commercialization. In the case, the hydraulic actuator 31
The following problems occur with the non-circular cross-sectional shape. That is, the operation of forming the inner peripheral surface of the cylinder chamber 32 and the outer peripheral edge of the piston 33 into an oval shape as shown in FIG. 11A or an elliptical shape as shown in FIG.
The possibility that these shapes and dimensions are different from the design values is higher than in the case of a circular shape. As a result, the possibility of malfunction of the assembled hydraulic actuator 31 is increased as compared with the case of a hydraulic actuator having a circular cross section.

In the case of the conventional structure shown in FIG. 10, the operation state of the hydraulic actuator 31 can be confirmed only by the trunnion 7 and the hydraulic actuator 3 with respect to the frame 30.
After assembling 1 etc. If the operation of the hydraulic actuator 31 is found to be defective in this state, the frame 30 and the trunnion 7 already assembled must be disassembled and reassembled with appropriate parts. Such a work is extremely time-consuming and undesirably deteriorates the manufacturing efficiency of the toroidal-type continuously variable transmission and increases the cost of the toroidal-type continuously variable transmission. The toroidal-type continuously variable transmission of the present invention has been invented in view of such circumstances.

[0026]

A toroidal-type continuously variable transmission according to the present invention has a casing, an input shaft, and an input-side disk similarly to the above-described conventionally known toroidal-type continuously variable transmission. , An output disk, a trunnion, a displacement shaft, a power roller, and an actuator. The input shaft is rotatably supported in the casing. The input side disk is supported around the input shaft so as to be rotatable together with the input shaft.
The output-side disk is arranged concentrically with the input-side disk with its inner surface facing the inner surface of the input-side disk, and is rotatable relative to the input-side disk. In addition, the trunnion has a plurality of pivots between the input side disk and the output side disk, each of which is provided in a pair with the input side disk and the output side disk, and which is in a twisted position with respect to the center axis of these two disks. It is provided swingably as the center. Also, one displacement shaft is provided for each trunnion so as to protrude from the inner surface of each trunnion. The power rollers are provided one for each trunnion so as to be rotatably supported on each of the displacement shafts, and are sandwiched between inner surfaces of the input side disk and the output side disk. ing. Further, the actuator displaces each of the trunnions in the axial direction of a pivot provided at each end.

In particular, in the toroidal-type continuously variable transmission according to the present invention, the actuator for displacing at least a part of the trunnions among the trunnions is provided on an extension of a pivot about the trunnions. Based on the supply and discharge of pressure oil to a pair of hydraulic chambers provided on both sides of
This is a double-acting hydraulic actuator that pushes and pulls a rod whose base end is connected to the piston. The cross-sectional shape of the piston constituting the hydraulic actuator and the cylinder in which the piston is oil-tightly fitted are elliptical or oval. The base end of the rod is coupled to the piston via a pair of thrust rolling bearings disposed on both sides of the piston so as to rotate freely relative to the piston and to be displaceable in the axial direction in synchronization with the piston. ing. Further, the double-acting hydraulic actuator is
The operation can be freely checked in a state where the cylinder, the rod, and each of the thrust rolling bearings are assembled.

[0028]

In the case of the toroidal type continuously variable transmission of the present invention constructed as described above, since the double-acting hydraulic cylinder has an elliptical or elliptical cross-sectional shape, a multiple cylinder for displacing each trunnion is provided. It is possible to reduce the installation space for the dynamic hydraulic actuator to reduce the size and weight. Also, since the operation of this hydraulic actuator can be checked before being incorporated into the toroidal type continuously variable transmission, it is possible to prevent the assembling work of the toroidal type continuously variable transmission from being troublesome and to prevent the toroidal type continuously variable transmission. The cost can be reduced by increasing the efficiency of the manufacturing operation.

[0029]

1 to 4 show an example of an embodiment of the present invention. This embodiment is a so-called double cavity type in which two input disks 2 and two output disks 4 are provided in parallel with each other in the power transmission direction. The figure shows a case where the present invention is applied to a toroidal-type continuously variable transmission in which three power rollers 9 are provided in total, three in each.
FIG. 2 shows only one of the cavities (portion for arranging the input side disk 2, the output side disk 4, and the power rollers 9, 9 to transmit power), but on the right side of FIG. Even there is another cavity. The basic structure and operation of such a double-cavity toroidal-type continuously variable transmission are well known in the related art, and therefore, illustration and description of the entire configuration are omitted.

Mounting part 41 provided on the inner surface of casing 5a
The frame 18 has studs 43, 4 which are inserted through mounting holes 42, 42 at three positions on the outer diameter side end of the frame 18.
3 and a nut 4 screwed onto each of these studs 43
4 and fixed. In the illustrated example, the gear housing 45 is fixed between the mounting portion 41 and the frame 18 by the studs 43 and 43 and the nut 44. On the inner diameter side of the gear housing 45, 1
An output sleeve 46 in which a pair of output side disks 4 are spline-engaged at both ends thereof is connected to a pair of rolling bearings 47, 47.
And the output sleeve 4
The output gear 48 provided on the outer peripheral surface of the intermediate portion 6 is housed inside the gear housing 45.

The frame 18 is formed in a star shape as a whole, and its radially intermediate portion or outer diameter side portion is formed in a forked shape, so that three holding portions 49, 49 are formed in a circumferential direction or the like. It is formed at intervals. And these holding parts 49, 4
9, the intermediate portions of the support pieces 19b, 19b are pivotally supported by the second pivots 50, 50 via needle bearings 51, 51, respectively. Each support piece 19
b, 19b are a cylindrical mounting portion 52 disposed around the second pivots 50, 50, and a pair of support plate portions 53 projecting radially outward from the outer peripheral surface of the mounting portion 52; 53. The crossing angle between the pair of support plate portions 53 is 120 degrees. Therefore, the support plate portions 53 of the support pieces 19b, 19b adjacent to each other in the circumferential direction are parallel to each other.

The support plates 53 have circular holes 54, 54, respectively. Each support piece 19
When b and 19b are in the neutral state, the circular holes 54 and 54 formed in the support plate portions 53 and 53 of the support pieces 19b and 19b adjacent in the circumferential direction are concentric with each other. Each trunnion 7a, 7b, 7 is inserted into each of the circular holes 54, 54.
The pivots 6, 6 provided at both ends of c are supported by radial needle bearings 55, 55. The outer peripheral surfaces of the outer rings 56, 56 constituting these radial needle bearings 55, 55 are spherical convex surfaces. The outer rings 56, 56 are fitted in the respective circular holes 54, 54 so as to be free from backlash and to be swingably displaceable.

Studs 58, 58 are screwed into the screw holes 57, 57 provided in the support plate portions 53, 53, and the end faces of the studs 58, 58 are connected to the trunnions 7a, 7b and 7c are in contact with both end faces. The tip surfaces of the studs 58, 58 are spherical convex surfaces, and the trunnions 7a, 7 between the pair of studs 58, 58 provided at positions facing each other.
The swing displacement of b and 7c is enabled. Lock nuts 59, 59 are provided at the base ends of these studs 58, 58.
Are screwed together so that these studs 58 do not inadvertently loosen. In addition, such studs 58, 58
Are three trunnions 7a provided in a single cavity,
It is provided to synchronize the displacement of the input side and output side discs 2 and 4 in the circumferential direction of the discs 7 and 7c via the support pieces 19b and 19b. The studs 58, 58 and the lock nuts 59, 59 may be omitted as long as the displacement can be sufficiently synchronized by a hydraulic actuator described later.

The above three trunnions 7a, 7b, 7c
As described above, the displacement of the discs 2 and 4 in the circumferential direction due to the swing of the support pieces 19b and 19b about the second pivots 50 and 50, respectively, Swing displacement about pivots 6, 6 provided at both ends is freely supported. In order to displace the trunnions 7a, 7b, 7c in the axial direction of the pivots 6, 6 provided at both ends thereof in order to perform a shift operation,
In the case of the toroidal type continuously variable transmission of the present invention, the following actuator is provided.

First, trunnions 7 provided on both upper sides in an inclined direction, corresponding to some trunnions described in the claims.
a and 7b are provided with double-acting hydraulic actuators 60a and 60b as shown in detail in FIG. 3 on the extension of the pivots 6 and 6 for these trunnions 7a and 7b, one for each of these trunnions 7a and 7b. Are provided. The trunnions 7a, 7b can be displaced in the axial direction of the pivots 6, 6 provided at both ends by supplying and discharging the pressure oil to and from the hydraulic actuators 60a, 60b.

Each of the above hydraulic actuators 60a, 60b
As shown in FIG. 4, the base end of the rod 63 (the lower end in FIG. 3) is oil-tightly fitted in a cylinder 61 having an oval cross section, )
Are rotatably connected in a state where the backlash in the axial direction (up and down direction in FIG. 3) is prevented. In the illustrated example, the piston 62 is sandwiched between a pair of thrust needle bearings 64, 64 in order to make the rotation freely. Since both surfaces of the piston 62 function as raceways of the thrust needle bearings 64, 64 are hardened and hardened, and the surface is finished to a smooth surface. In the illustrated example, in order to prevent backlash in the axial direction, the piston 62 and a pair of thrust needle bearings 64, 64 are connected to an outward flange-like flange 65 provided at an intermediate portion of the rod 63. The rod 63 is sandwiched between a tapered snap ring 66 locked at a portion near the base end of the rod 63. In addition, this taper snap ring 66
Instead, a male screw portion is provided at a portion near the base end of the rod 63, and a nut is screwed into the male screw portion, so that the pair of thrust needle bearings 64, 64 can be connected to the flange portion 65. It can also be sandwiched between.

Each of the hydraulic actuators 60a as described above,
A male screw is formed on the outer peripheral surface of the first half (upper half of FIG. 3) of the rod 63 constituting the 60b. The distal end of such a rod 63 is screwed into a screw hole 67 provided at the center of the pivot 6 projecting from one end face (lower end face in FIG. 1) of each of the trunnions 7a and 7b. It is fixed by. In this state, the trunnions 7a, 7b are displaced in the axial direction of the pivots 6, 6 provided at both ends thereof by supplying and discharging pressure oil to and from the hydraulic actuators 60a, 60b. Each of the hydraulic actuators 60
a and 60b are assembled as shown in FIG. 3, and before and after being assembled into the toroidal-type continuously variable transmission, supply and discharge pressure oil into and out of a pair of hydraulic chambers partitioned by the piston 62, thereby performing the operation. You can check the status.

In the illustrated example, the rod 63 constituting each of the hydraulic actuators 60a and 60b has a circular tubular shape. Then, the base end of the rod 63 (FIG. 1,
3 is connected to a downstream end of an oil supply hose (not shown) having flexibility, so that lubricating oil can be fed into the rod 63. During operation of the toroidal-type continuously variable transmission, lubricating oil (traction oil) is fed into the rod 63 from an oil feed pump (not shown). The lubricating oil fed into the rod 63 is used for lubricating the rolling contact portions and the like of the toroidal type continuously variable transmission. That is, a part of this lubricating oil is
a, 7b, which are ejected from the nozzle holes 69, 69 provided on the inner surfaces 2 of the input side disk 2 and the output side disk 4.
a, 4a and lubricating a rolling contact portion between the peripheral surface 9a of the power roller 9 supported by each of the trunnions 7a, 7b.

The remainder of the lubricating oil is passed through lubricating oil passages 70 provided inside the trunnions 7a and 7b.
It is sent to each rolling bearing and the sliding contact portion.
First, the lubricating oil can be sent through the throttle plug 71 to the radial needle bearings 55 supporting the pivots 6. Also, a sliding contact portion between the tip end surface of the stud 58 and each of the trunnions 7a and 7b,
It can be fed through another aperture plug 72.
Further, the remaining lubricating oil is used to support the power roller 9 for each of the trunnions 7a and 7b, the thrust needle bearing 15 and the thrust ball bearing 14, the displacement shaft 8, the trunnions 7a and 7b, and the power roller 9 It can be fed into the radial needle bearing provided between them.

On the other hand, the remaining trunnion 7c provided in the lower center in the horizontal direction is displaced by a pair of hydraulic actuators 73a and 73b provided below both ends of the trunnion 7c via link arms 74a and 74b, respectively. It is free. Each of these hydraulic actuators 73a,
73b pushes the rod 76 by supplying the pressure oil into the cylinder 75. Even if the supply of the pressure oil to the cylinder 75 is stopped, this rod 76
Is not drawn into the cylinder 75, and is of a single-acting type. Each of the above hydraulic actuators 73
a and 73b concentrically move the rods 76 in opposite directions to each other, and more specifically, move the rod 76 based on the supply of pressure oil to another hydraulic actuator 73a.
(Or 73b), and is supported and fixed in the casing 5a so as to be pushed away from the casing 5a.

Each of the link arms 74a and 74b has an intermediate portion supported by a hollow cylindrical third pivot 77 so as to be swingable. Each of these third pivots 77, 77 is parallel to said second pivot 50, 50,
The inside communicates with a discharge port of a fuel pump (not shown).

In the illustrated example, each of the link arms 74
Cylindrical convex portions 78 are formed on the mutually facing surfaces of the distal ends of a and 74b. On the other hand, the trunnion 7
A circular hole 79 having an inner diameter larger than the outer diameter of the cylindrical projection 78 is formed at the center of the pivots 6 provided at both ends of the cylindrical projection 78.
Are formed in such a manner as to open at the end faces of the pivots 6 and 6. The cylindrical projections 78 of the link arms 74a and 74b are loosely inserted into the circular holes 79. In this state, the inner peripheral edge of the O-ring 80 engaged with the inner peripheral surface of the circular hole 79 is elastically brought into contact with the outer peripheral surface of the intermediate portion of the cylindrical convex portion 78 over the entire periphery. Oil tightness is maintained between the inner peripheral surface of the hole 79 and the outer peripheral surface of the cylindrical projection 78.

A thrust needle bearing 81 is provided between the end surfaces of the pivots 6 and 6 and the side surfaces of the distal ends of the link arms 74a and 74b. Of the pair of races constituting the thrust needle bearing 81, one surface of the race 82 on the side of each of the link arms 74a and 74b, which is in contact with the side surface of the distal end of each of the link arms 74a and 74b is spherical. It has a convex surface. With such a structure, the transmission of the displacement between the link arms 74a, 74b and the trunnion 7c can be freely performed, and the link arms 74a, 74b centered on the third pivots 77, 77, respectively. Smooth swing displacement and smooth swing displacement of the trunnion 7c around the pivots 6, 6 are allowed.

Each of the link arms 74a, 7 whose respective intermediate portions are pivotally supported by such third pivots 77, 77.
4b, one side of each base end (lower end in FIG. 1) abuts against the front end of a rod 76 constituting each of the hydraulic actuators 73a and 73b, and one side of each front end (upper end in FIG. 1). The side is engaged with ends of pivots 6 provided at both ends of the trunnion 7c. A portion of the base end of each of the link arms 74a and 74b that abuts on the distal end surface of the rod 76 is a partially cylindrical convex curved surface so that the swinging displacement of the abutting portion is smoothly performed.

Further, lubricating oil can be freely fed from an oil feed pump (not shown) into the third pivots 77, 77, and the inside of the third pivots 77, 77 and the cylindrical projections. The inside of the portion 78 is connected to each of the link arms 74a,
A concave groove 83 formed at an axially intermediate portion of the center hole of the central hole 74b;
These link arms 74a and 74b communicate with each other via an oil passage hole 84 formed inside the first half (upper half of FIG. 1). The downstream end opening of the oil passage hole 84 is closed by a plug 85. Accordingly, the entire amount of the lubricating oil fed from the oil feed pump (not shown) into each of the third pivots 77 is sent into the circular hole 79 provided at the center of each of the pivots 6. . The lubricating oil sent into the circular hole 79 in this manner is supplied to each of the actuators 60 described above.
As in the case of the lubricating oil fed into the rods 63a and 60b, the lubricating oil is used for lubricating each part.

The supply and discharge of pressure oil to and from the hydraulic actuators 60a and 60b, each of which is a double-acting type, and the supply and discharge of hydraulic oil to the pair of hydraulic actuators 73a and 73b, each of which is a single-acting type. The supply and discharge of the pressure oil are performed by a single control valve 21 (see FIG. 9) in synchronization with each other. And, the three trunnions 7a, 7b, 7c
Are displaced by the same length in the same direction with respect to the rotation direction of both the input side and output side disks 2, 4. The displacement of the trunnions 7a, 7b, 7c is also mechanically synchronized by the studs 58, 58, as described above.
Also, the trunnions 7a, 7b, 7c are provided with hydraulic actuators 73a, 73b, 60a, 6
0b, each member is elastically deformed by transmitting a force for displacement, and each trunnion 7a, 7b, 7
There is no difference in the displacement of c. Therefore, the displacement amounts of these trunnions 7a, 7b, 7c are strictly matched.

Each of these trunnions 7a, 7b, 7c
On the basis of the displacements synchronized in this manner, the swinging motions are made about the pivots 6 provided at both ends. That is, based on this displacement, as described above, the force applied in the tangential direction to the rolling contact portion between the peripheral surfaces 9a, 9a of the power rollers 9, 9 and the inner surfaces 2a, 4a of the discs 2, 4 is determined. The direction changes. Due to this change, the trunnions 7a, 7b, 7c are oscillated about the pivots 6, 6 provided at both ends thereof. The displacement of each of the trunnions 7a, 7b, 7c performed in this manner is performed by any of the trunnions 7a (upper left side in FIG. 1).
The rod 63 is taken out by a precess cam 28 fixed around a portion near the base end of the rod 63 connected to the rod. And
The displacement of the precess cam 28 via the link 29
The control signal is transmitted to the spool 24 of the control valve 21 (FIG. 9), and the opening and closing of the control valve 21 is controlled. The control of this portion is the same as in the case of the conventional structure shown in FIG.

In the toroidal type continuously variable transmission of the present invention constructed and operated as described above, the hydraulic actuators 60a and 60b provided on the left and right, each of which is a double-acting type, have an oval cross section. Actuator 60
a, 60b, while securing the pressure receiving area of the piston 62, these hydraulic actuators 60a, 60b
The amount of protrusion in the radial direction from the outer peripheral edges of both the input side and output side disks 2, 4 can be reduced. That is, if the hydraulic actuators 60a and 60b are arranged in such a manner that the front and back directions in FIG. 1 coincide with the major axis direction, the amount of protrusion can be reduced. In other words, the hydraulic actuators 60a and 60b can be efficiently arranged, and the outer dimensions of the casing 5a that houses the toroidal-type continuously variable transmission can be reduced. As a result, the size and weight of the toroidal type continuously variable transmission can be reduced, so that the degree of freedom in designing a vehicle incorporating the toroidal type continuously variable transmission can be increased.

Further, each of the above hydraulic actuators 60a,
As described above, the operation of the No. 60b can be confirmed before being incorporated in the toroidal type continuously variable transmission. For this reason, the hydraulic actuators 60a and 60b that do not operate normally are incorporated into the casing 5a together with other components as shown in FIG.
This eliminates the need to disassemble this later. As a result,
The assembly work of the toroidal-type continuously variable transmission can be prevented from being troublesome, and the cost can be reduced by increasing the efficiency of the manufacturing operation of the toroidal-type continuously variable transmission.

[0050]

Since the present invention is constructed and operates as described above, the present invention can reduce the cost of a toroidal type continuously variable transmission which can transmit a large amount of power and can be assembled in a small and limited installation space. Thus, it is possible to contribute to the practical use of such a toroidal type continuously variable transmission.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating an example of an embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a sectional view showing a double-acting hydraulic actuator taken out therefrom.

FIG. 4 is a view as seen from above in FIG. 3;

FIG. 5 is a side view showing a basic configuration of a conventionally known toroidal type continuously variable transmission in a state of maximum deceleration.

FIG. 6 is a side view similarly showing a state at the time of maximum speed increase.

FIG. 7 is a sectional view showing an example of a conventional specific structure.

FIG. 8 is a sectional view taken along line BB of FIG. 7;

FIG. 9 is a fragmentary front view showing an example of a conventionally known structure for increasing the power that can be transmitted, with a part thereof cut off.

FIG. 10 is a cross-sectional view of a main part showing an example of a conventionally known structure that can reduce the assembly dimensions of an actuator.

FIG. 11 is a schematic sectional view taken along the line CC of FIG. 10;

[Explanation of symbols]

 Reference Signs List 1 input shaft 2 input side disk 2a inner surface 3 output shaft 4 output side disk 4a inner surface 5, 5a casing 6 pivot 7, 7, 7a, 7b, 7c trunnion 8 displacement shaft 9 power roller 9a peripheral surface 10 loading cam device 11 input shaft Reference Signs List 12 output gear 13 support plate 14 thrust ball bearing 15 thrust needle bearing 16 outer ring 17 actuator 18 frame 19, 19a, 19b support piece 20 hydraulic actuator 21 control valve 22 pump 23 sleeve 24 spool 25 control motor 26 drive piston 27 oil reservoir 28 precess cam 29 Link 30 Frame 31 Hydraulic Actuator 32 Cylinder Chamber 33 Drive Piston 34 Seal Ring 35a, 35b Hydraulic Chamber 36 Circular Tube Part 37 Sleeve 38a, 38b Thrust Rolling Bearing 39 Bolt 4 Head 41 Mounting part 42 Mounting hole 43 Stud 44 Nut 45 Gear housing 46 Output sleeve 47 Rolling bearing 48 Output gear 49 Holding part 50 Second pivot 51 Needle bearing 52 Mounting part 53 Support plate part 54 Circular hole 55 Radial needle bearing 56 Outer ring 57 Screw hole 58 Stud 59 Lock nut 60a, 60b Hydraulic actuator 61 Cylinder 62 Piston 63 Rod 64 Thrust needle bearing 65 Flange 66 Taper snap ring 67 Screw hole 68 Lock nut 69 Nozzle hole 70 Lubricating oil passage 71 Throttle plug 72 Throttle Plug 73a, 73b Hydraulic actuator 74a, 74b Link arm 75 Cylinder 76 Rod 77 Third pivot 78 Cylindrical projection 79 Circular hole 80 O-ring 81 Thrust needle bearing 82 Track ring 8 3 concave groove 84 oil passage hole 85 plug

Claims (1)

[Claims] 1. A casing, an input shaft rotatably supported in the casing, an input disk rotatably supported around the input shaft together with the input shaft, and an inner surface thereof connected to the input side. An output disk disposed concentrically with the input disk in a state facing the inner surface of the disk, and rotatable relative to the input disk, and provided between the input disk and the output disk. A plurality of trunnions provided for each of a pair of input-side disks and an output-side disk that swing about a pivot axis which is twisted with respect to the center axis of the two disks, and inner surfaces of the respective trunnions. And one input shaft and one output disk which are rotatably supported by each of these trunnions. Between the inner surfaces of the
In a toroidal-type continuously variable transmission having one power roller for each trunnion and an actuator for displacing each trunnion in the axial direction of a pivot provided at each end of the trunnion, An actuator for displacing at least a part of the trunnion is provided on an extension of a pivot about the trunnion,
A double-acting hydraulic actuator for pushing and pulling a rod having a base end connected to the piston based on the supply and discharge of hydraulic oil to a pair of hydraulic chambers provided on both sides of the piston. The cross-sectional shape of the piston and the cylinder in which the piston is oil-tightly fitted is elliptical or elliptical, and the base end of the rod is a pair of a pair disposed on both sides of the piston with respect to the piston. Via a thrust rolling bearing, the piston is rotatably coupled to the piston and axially displaceable in synchronism with the piston.The double-acting hydraulic actuator comprises the cylinder, the rod, and each of the thrust rolling bearings. A toroidal-type continuously variable transmission characterized in that the operation can be freely checked in the assembled state.