JPH08145134A - Troidal type continuously variable transmission - Google Patents

Abstract

PURPOSE: To allow installation of a continuously variable transmission in a restricted space by lessening its outside dimensions. CONSTITUTION: When the gearing ratio is to be changed, a turnnion 6 is displaced in the axial direction of pivots 5, 5 by an actuator which is composed of a drive piston 37a and a hydraulic cylinder 38a. The peripheral shape of the drive piston 37a and the bore shape of the cylinder 38a are made in a long circle or ellipse. Increase in the outside dimensions caused by actuator is suppressed by locating the minor diameter on the side where the amount of protrusion is to be inhibited.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The toroidal type continuously variable transmission according to the present invention is used, for example, as a transmission for an automobile.

[0002]

2. Description of the Related Art The use of a toroidal type continuously variable transmission as schematically shown in FIGS. 8 to 9 has been studied as a transmission for an automobile. This toroidal type continuously variable transmission supports an input side disk 2 concentrically with the input shaft 1 as disclosed in, for example, Japanese Utility Model Laid-Open No. 62-71465, and the input shaft 1
At the end of the output shaft 3 arranged concentrically with the output side disk 4
Is fixed. Inside the casing (not shown) in which the toroidal type continuously variable transmission is housed, the trunnions 6, 6 swinging around the pivots 5, 5 which are in a twisted position with respect to the input shaft 1 and the output shaft 3. Is provided. The center axes of the input shaft 1 and the output shaft 3 are the center axes of the input side and output side disks 2 and 4.

Each trunnion 6, 6 is provided with the above-mentioned pivots 5, 5 on the outer surface of both ends. Further, the base half of the displacement shafts 7, 7 is supported at the center of each trunnion 6, 6, and each trunnion 6, 6 is swung about the pivot shafts 5, 5, so that each displacement shaft 7, The inclination angle of 7 can be freely adjusted. Power rollers 8, 8 are rotatably supported around the front half of the displacement shafts 7, 7 supported by the trunnions 6, 6, respectively. And, each power roller 8,8,
It is sandwiched between the input side and output side disks 2 and 4.

The inner surfaces 2a, 4a of the input-side and output-side disks 2, 4 facing each other have a cross-section of a concave surface obtained by rotating an arc about the pivot 5. Then, the peripheral surfaces 8a, 8a of the power rollers 8, 8 formed in the spherical convex surface are brought into contact with the inner side surfaces 2a, 4a.

A loading cam type pressing device 9 is provided between the input shaft 1 and the input side disc 2, and the input side disc 2 is elastically directed toward the output side disc 4 by the pressing device 9. Pressing. This pressing device 9
Is a cam plate 10 that rotates together with the input shaft 1, and a retainer 11.
A plurality of (for example, four) rollers 12 held by
It is composed of 12 and. A cam surface 13, which is an uneven surface extending in the circumferential direction, is formed on one side surface (right side surface of FIGS. 8 to 9) of the cam plate 10, and an outer surface (left side of FIGS. 8 to 9) of the input side disk 2 is formed. The same cam surface 14 is also formed on the surface). Then, the plurality of rollers 12, 12 are rotatably supported around a shaft in the radial direction with respect to the center of the input shaft 1.

When the toroidal type continuously variable transmission constructed as described above is used, when the cam plate 10 rotates as the input shaft 1 rotates, the cam surface 13 causes the plurality of rollers 12, 1 to rotate.
2 is pressed against the cam surface 14 on the outer surface of the input side disk 2. As a result, the input side disk 2 is pressed by the plurality of power rollers 8, 8 and at the same time, based on the pressing of the pair of cam surfaces 13, 14 and the plurality of rollers 12, 12. The input side disk 2 rotates. And
The rotation of the input side disk 2 is transmitted to the output side disk 4 via the plurality of power rollers 8 and the output shaft 3 fixed to the output side disk 4 rotates.

When the rotational speeds of the input shaft 1 and the output shaft 3 are changed, and when deceleration is first performed between the input shaft 1 and the output shaft 3, the trunnions 6, 6 centering on the pivot shafts 5, 5 are used.
As shown in FIG. 8, the peripheral surfaces 8a and 8a of the power rollers 8 and 8 are moved toward the center of the inner side surface 2a of the input side disk 2 and the outer peripheral side portion of the inner side surface 4a of the output side disk 4. The displacement shafts 7, 7 are tilted so as to abut with and respectively.

On the other hand, when increasing the speed, the trunnions 6, 6 are swung so that the peripheral surfaces 8a, 8a of the power rollers 8, 8 of the input side disk 2 as shown in FIG. The outer peripheral portion of the inner side surface 2a and the inner side surface 4 of the output side disk 4
The displacement shafts 7, 7 are tilted so that they are brought into contact with the central portions of a. By setting the inclination angles of the displacement shafts 7, 7 in the middle between FIG. 8 and FIG. 9, an intermediate gear ratio can be obtained between the input shaft 1 and the output shaft 3.

Further, FIGS. 10 to 11 show Japanese Patent Application No. Sho 63-69.
1 shows a more specific toroidal type continuously variable transmission described in a microfilm of No. 293 (Actual Kaihei No. 1-173552). The input side disk 2 and the output side disk 4 are rotatably supported around a circular tubular input shaft 15 via needle bearings 16 and 16, respectively.
The cam plate 10 is spline-engaged with the outer peripheral surface of the end portion (the left end portion in FIG. 10) of the input shaft 15 and is prevented from moving in the direction away from the input side disk 2 by the collar portion 17. The cam plate 10, the rollers 12 and 12 and the cam surface 14 on the outer surface of the input side disk 2 constitute a loading cam type pressing device 9. An output gear 18 is connected to the output side disk 4 by keys 19 and 19 so that the output side disk 4 and the output gear 18 rotate in synchronization with each other.

Both ends of the pair of trunnions 6, 6 are supported by the pair of support plates 20, 20 so as to be swingable and displaceable in the axial direction (front and back directions in FIG. 10, left and right directions in FIG. 11). There is. Then, the base halves of the displacement shafts 7, 7 are supported by the circular holes 23, 23 formed in the intermediate portions of the trunnions 6, 6. Each of these displacement shafts 7, 7 has a supporting shaft portion 21, 21 and a pivot shaft portion 22, 22 that are parallel to each other and are eccentric. Of these, the support shaft portions 21 and 21 forming the base half of the displacement shafts 7 and 7 are connected to the circular holes 23 and
Inside 23, it is rotatably supported via radial needle bearings 24, 24. In addition, the displacement shafts 7 and 7 described above
The power rollers 8, 8 are rotatably supported around the respective pivot shafts 22, 22 constituting the first half of the above through radial needle bearings 25, 25.

The pair of displacement shafts 7, 7 are provided at positions opposite to the input shaft 15 by 180 degrees. or,
The direction in which the pivot shafts 22, 22 of the displacement shafts 7, 7 are eccentric with respect to the support shafts 21, 21 is the same as the rotation direction of the input side and output side disks 2, 4. In FIG. 11, the left and right directions are reversed. Also, the eccentric direction is
The direction is substantially orthogonal to the arrangement direction of the input shaft 15. Therefore, the power rollers 8, 8 are supported so as to be slightly displaceable in the arrangement direction of the input shaft 15.

Further, between the outer side surface of each of the power rollers 8 and 8 and the inner side surface of the intermediate portion of each of the trunnions 6 and 6, in order from the outer surface side of each of the power rollers 8 and 8, there is a thrust ball bearing. 26, 26 and thrust needle bearings 27, 2
7 and are provided. Of these, thrust ball bearings 26, 2
Reference numeral 6 allows the power rollers 8 and 8 to rotate while bearing the load in the thrust direction applied to the power rollers 8 and 8. Such thrust ball bearings 26, 26 are each provided with a plurality of balls 29, 29 and each ball 29, 29.
It is composed of an annular retainer 28, 28 for rotatably holding and an annular outer ring 30, 30. The inner ring races of the thrust ball bearings 26, 26 are formed on the outer side surfaces of the power rollers 8, 8 and the outer ring races are formed on the inner side surfaces of the outer rings 30, 30 respectively.

The thrust needle bearings 27, 27 are also provided.
Is composed of a race 31, a retainer 32, and needles 33, 33. Of these, the race 31 and the cage 32 are combined so as to be slightly displaceable in the rotational direction. Such thrust needle bearings 27, 27 are provided between the inner surfaces of the trunnions 6 and 6 and the outer surfaces of the outer rings 30, 30 in a state where the races 31, 31 are in contact with the inner surfaces of the trunnions 6, 6. It is sandwiched. The thrust needle bearings 27 and 27 as described above support the thrust load applied from the power rollers 8 and 8 to the outer rings 30 and 30, while the pivot shafts 22 and 22 and the outer rings 30 and 30 are supported by the thrust bearings 27 and 27. It is allowed to swing around the support shaft portions 21, 21.

Further, drive rods 36, 36 are provided at one end (the left end in FIG. 11) of each trunnion 6, 6 respectively.
And drive pistons 37, 37 are fixedly provided on the outer peripheral surfaces of the intermediate portions of the drive rods 36, 36. The drive pistons 37, 37 are oil-tightly fitted in the drive hydraulic cylinders 38, 38, respectively. Hydraulic cylinders 38, 3 fitted with the respective drive pistons 37, 37
Reference numeral 8 constitutes an actuator for displacing the trunnions 6, 6.

In the case of the toroidal type continuously variable transmission configured as described above, the rotation of the input shaft 15 is transmitted to the input side disk 2 via the pressing device 9. Then, the rotation of the input side disk 2 is transmitted to the output side disk 4 via the pair of power rollers 8, 8 and further the output side disk 4
Rotation is taken out from the output gear 18.

When the rotation speed ratio between the input shaft 15 and the output gear 18 is changed, the pair of drive pistons 37,
37 is displaced in opposite directions. As the drive pistons 37, 37 are displaced, the pair of trunnions 6,
6 are displaced in opposite directions, for example, the lower power roller 8 in FIG. 11 is displaced to the right side in FIG. 11, and the upper power roller 8 in FIG. 11 is displaced to the left side in FIG. As a result,
The peripheral surfaces 8a, 8a of each of the power rollers 8, 8 and the inner side surfaces 2a, 4 of the input side disk 2 and the output side disk 4, respectively.
The direction of the tangential force acting on the contact portion with a changes. The trunnions 6, 6 are pivotally supported by the support plates 20, 20 in accordance with the change in the direction of the force.
It swings in directions opposite to each other with 5 as the center. As a result,
As shown in FIGS. 8 to 9 described above, each of the power rollers 8,
The abutting positions of the peripheral surfaces 8a, 8a of 8 and the respective inner side surfaces 2a, 4a change, and the rotation speed ratio between the input shaft 15 and the output gear 18 changes.

In this way, in order to change the rotation speed ratio between the input shaft 15 and the output gear 18, the displacement shafts 7, 7 are
When the inclination angle of is changed, the displacement shafts 7, 7 slightly rotate about the support shaft portions 21, 21.
As a result of this rotation, the outer side surfaces of the outer rings 30, 30 of the thrust ball bearings 26, 26 and the inner side surfaces of the trunnions 6, 6 are relatively displaced. Since the thrust needle bearings 27, 27 are present between the outer side surface and the inner side surface, the force required for this relative displacement is small.

[0018]

When the toroidal type continuously variable transmission constructed and operated as described above is used as a transmission for an automobile, it is necessary to make the outer diameter as small as possible. This is because the transmission for an automobile must be installed in a limited installation space in the engine room (for example, in the case of FF vehicles) or in the tunnel formed in the floor panel (for example, in the case of FR vehicles). is there. When looking at the structure of the toroidal type continuously variable transmission from the aspect of reducing the outer dimensions, the hydraulic cylinders, which are actuators for displacing the trunnions 6 and 6, respectively, are fitted with the drive pistons 37 and 37, respectively. Parts 38 and 38 become a bottleneck for miniaturization.

The main reason why the hydraulic cylinders 38, 38 become a bottleneck in downsizing the toroidal type continuously variable transmission is as follows.
Although the installation positions of the hydraulic cylinders 38, 38 are outside the other components because the trunnions 6, 6 need to be displaced in the axial direction of the pivots 5, 5, the hydraulic cylinders 38, 38 are not installed. This is because the capacity of must be sufficiently large. That is, when the toroidal type continuously variable transmission is in operation, a large load is applied to each trunnion 6, 6 from each power roller 8, 8 via the displacement shaft 7, 7 in the axial direction of the pivot shafts 5, 5. In each of the hydraulic cylinders 38, 38,
A capacity is required to prevent the trunnions 6, 6 from being displaced by the large load.

For example, let T _e be the torque of the power to be transmitted by the toroidal type continuously variable transmission, and let R ₁ be the radius of rotation of the contact point between the inner surface 2 a of the input side disk 2 and the peripheral surface 8 a of the power roller 8. , When the total number of the power rollers 8, 8 constituting the toroidal type continuously variable transmission is n, the capacity (supportable force) F _p required for each of the hydraulic cylinders 38, 38 is ) Is represented by the formula. F _p = 2T _e / n · R ₁ --- (1)

The value of F _p expressed by the equation (1) becomes considerably large. In order to obtain such a large capacity,
When the pressure in the high pressure chamber of the hydraulic cylinder 38 fitted with the drive piston 37 having an effective area of A _p is P _H and the pressure in the low pressure chamber is P _L , the following equation (2) is established. F _p = A _p (P _H −P _L ) −−− (2)

As is apparent from the equation (2), in order to secure the capacity F _p , the effective area A _p is increased or the pressure P _{H of the} high pressure chamber and the pressure P _{L of the} low pressure chamber are set. The difference (P _H −P _L ) must be increased. (P _H −
Increasing P _L ) has a limit in terms of the ability of the pump to generate hydraulic pressure, or to suppress the power loss accompanying driving this pump to a low level. For this reason, the effective area A _p must be increased, and as described above, the hydraulic cylinders 38, 38 become a bottleneck for miniaturization. The toroidal type continuously variable transmission of the present invention was invented in view of such circumstances.

[0023]

All of the toroidal type continuously variable transmissions according to the present invention, like the above-mentioned conventional toroidal type continuously variable transmission, have an input side disk whose inner surface has a concave curved surface of a rotating arc shape. And an output side disk whose inner side surface facing the inner side surface of this input side disk is a concave curved surface of a rotating arc shape, and each peripheral surface is a spherical convex surface, and this peripheral surface and the input side,
A plurality of power rollers provided between the input side and output side discs and the respective power rollers can be rotatably attached to the respective first halves while the inner side faces of the output side discs are in contact with each other. The same number of displacement shafts as the power rollers to be supported, the same number of trunnions as the power rollers to support the base half of each of these displacement shafts, and the trunnions provided at both ends of each of the trunnions. It is provided with pivots arranged in a twisted positional relationship with respect to the central axes of both the input side and output side disks, and actuators for displacing the trunnions along the axial direction of these pivots.

Particularly, in the toroidal type continuously variable transmission of the present invention, in the toroidal type continuously variable transmission according to claim 1, the actuator is a fixed hydraulic cylinder and an inside of the hydraulic cylinder. An oiltightly fitted drive piston and a rod member connecting the drive piston and the pivot are provided. The cross-sectional shapes of the inner peripheral surface of the hydraulic cylinder and the outer peripheral surface of the drive piston are oval or elliptical.

Further, in the toroidal type continuously variable transmission according to a second aspect of the present invention, the actuator includes a rod member whose one end is coupled to the pivot and an axial direction at a plurality of intermediate positions of the rod member. A plurality of drive pistons which are fixed to each other at a distance from each other, and a fixed hydraulic cylinder which is provided independently of each other and in which these drive pistons are oil-tightly fitted.

[0026]

In the toroidal type continuously variable transmission of the present invention configured as described above, even if the drive piston and the hydraulic cylinder forming the actuator have sufficient cross-sectional areas in order to increase the capacity of the actuator, The diametrical dimension of the hydraulic cylinder can be made small (in the case of claim 1) or entirely (in the case of claim 2). 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 miniaturized.

[0027]

1 to 3 show a first embodiment of the present invention corresponding to claim 1. The feature of the present invention resides in that a hydraulic cylinder that constitutes an actuator for displacing the trunnion 6 in the axial direction of the pivots 5 and 5 (vertical direction in FIG. 1) in order to downsize the toroidal type continuously variable transmission. The point is that the cross-sectional shapes of the inner peripheral surface and the outer peripheral surface of the drive piston are devised.
Since the configuration and operation of the other parts are the same as those of the conventional structure described above, duplicate description will be omitted or simplified, and the characteristic part of the present invention will be mainly described below.

In order to support the trunnion 6, the toroidal type continuously variable transmission is fixed in a housing 39 (see FIGS. 4 to 6 showing a concrete structure of the present invention, omitted in FIGS. 1 to 3). A hydraulic cylinder 38a is provided in the frame 40. The frame 40 includes a plurality of (three in the illustrated example) fixing plates 41a and 41 each having sufficient rigidity, such as an aluminum alloy plate material and a die cast molding material.
b and 41c are overlapped. Among them, the fixed plate 41a facing the trunnion 6 and the intermediate fixed plate 41b constitute the hydraulic cylinder 38a. The sectional shape of the inner peripheral surface 42 of the hydraulic cylinder 38a is the same as the sectional shape of the outer peripheral surface of the drive piston 37a described below. Further, circular holes 43, 43 are formed in a part of each of the fixing plates 41a, 41b, 41c. The central axes of these circular holes 43, 43 are the same as those of the hydraulic cylinder 38.
It is aligned with the central axis of a.

A drive piston 37a is fitted in the hydraulic cylinder 38a so as to be displaceable in the axial direction (vertical direction in FIG. 1). The cross-sectional shape of the outer peripheral surface of the drive piston 37a is an elliptical shape as shown in FIG.
It has an elliptical shape as shown in. Also, this drive piston 3
The outer peripheral edge of the seal ring 44 mounted on the outer peripheral surface of 7a is brought into sliding contact with the inner peripheral surface 42 of the hydraulic cylinder 38a, so that the inner side of the hydraulic cylinder 38a is paired with a pair of chambers 45a which are oil-tightly separated from each other. It is divided into 45b. When displacing the trunnion 6 in the axial direction of the pivot shafts 5 and 5, these chambers 45a, 4a
Supply and discharge pressure oil to 5b.

A circular pipe portion 46 is fixedly provided at the center of the drive piston 37a.
It has been inserted in 3, 43. The seal rings 47, 47 locked to the outer peripheral surface of the circular pipe portion 46 ensure oil-tightness between the outer peripheral surface of the circular pipe portion 46 and the inner peripheral surfaces of the circular holes 43, 43. ing. Further, a bolt 48, which is a rod member for connecting the drive piston 37a and the pivot 5 to each other, is inserted inside the circular pipe portion 46 so that the bolt 48 can freely rotate with respect to the circular pipe portion 46. The tip of the bolt 48 is screwed into a screw hole 49 formed at the center of the pivot 5 at one end (lower end in FIG. 1) of the trunnion 6.

Further, between the one end surface (the upper end surface in FIG. 1) of the circular pipe portion 46 and the pivot shaft 5, in order from the pivot shaft 5 side, the sleeve 50 also serving as the lock nut and the thrust rolling bearing 51a. And are provided. On the other hand, a thrust rolling bearing 51b is provided between the other end surface (the lower end surface in FIG. 1) of the circular pipe portion 46 and the head portion 52 of the bolt 48. Therefore, the bolt 48 and the pivot 5 and the trunnion 6 to which the ends of the bolt 48 are connected are the same as the drive piston 37.
It is rotatable with respect to a.

The reason why the pivot shaft 5 and the trunnion 6 are made rotatable with respect to the drive piston 37a is as follows. When changing the gear ratio by the toroidal type continuously variable transmission, the trunnion 6 swings around the pivots 5 and 5. Since the outer peripheral surface of the drive piston 37a and the inner peripheral surface 42 of the hydraulic cylinder 38a are oval or elliptical, the drive piston 37a cannot rotate. Therefore, the pivot 5 and the trunnion 6 are made rotatable with respect to the drive piston 37a as described above, so that the shift operation can be performed. Incidentally, the thrust rolling bearings 51a, 51b described above.
For this, a thrust roller bearing as shown in detail in FIG. 3 is used.

In the toroidal type continuously variable transmission of the present invention constructed as described above, in order to support the large thrust load applied to the trunnion 6, the capacity of the actuator is increased. Therefore, the drive piston 37a constituting this actuator is formed.
Also, even when the cross-sectional area of the hydraulic cylinder 38a is sufficiently secured, the dimension of the hydraulic cylinder 38a in the diametrical direction 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 miniaturized.

For example, FIGS. 4 to 5 show the input side disks 2 and 2 and the output side disks 4 and 4 in order to transmit a large torque.
1 shows a state in which the present invention is applied to a so-called double cavity type toroidal type continuously variable transmission having two sets of and.
In such a double-cavity type toroidal continuously variable transmission, a pair of input side disks 2 and 2 are provided at both ends of one input shaft 54 which is rotationally driven through the pressing device 9. It is locked so that it can rotate with it. A pair of output side disks 4, 4 are provided around the middle of the input shaft 54.
Are rotatably supported with respect to the input shaft 54.
During operation of the toroidal type continuously variable transmission, the pair of output side disks 2, 2 to the pair of output side disks 4, 4,
Power is transmitted via two power rollers 8 each. Then, these output side disks 4, 4
The power transmitted to the motor is taken out through the sleeve 55 and the output gear 56.

In the double-cavity type toroidal type continuously variable transmission as described above, a plurality of hydraulic cylinders 38a, 38a corresponding to the number of trunnions 6, 6 are provided on the lower side of the main body of the toroidal type continuously variable transmission. Are arranged in 2 columns and 2 rows. This is to prevent the hydraulic cylinders 38a, 38a having a large cross-sectional area from projecting upward or laterally and enabling installation in a limited space such as a floor tunnel. The interval (pitch) between the adjacent hydraulic cylinders 38a, 38a is narrow in the width direction (left and right direction in FIG. 4, front and back direction in FIG. 5) of the toroidal type continuously variable transmission, and the length direction (FIG. 4). It becomes wider in the front and back direction, and in the left and right direction in FIG. Therefore, the drive piston 3 whose peripheral surface has an oval or elliptical cross section
If the actuators 7a and 37a and the hydraulic cylinders 38a and 38a are arranged so that the major axis direction of the oval or elliptical shape is aligned with the above length direction, the external dimensions of the toroidal type continuously variable transmission can be increased. In addition, the capacity of the actuator can be sufficiently increased. Then, the pressure difference between the high pressure chamber and the low pressure chamber (“P _H −P _L ” in the equation (2) can be reduced by the increase in the capacity of the actuator. As a result, the toroidal type continuously variable transmission is driven. The hydraulic pump can be made smaller to reduce the power loss due to the hydraulic pump, in other words, the efficiency of the toroidal type continuously variable transmission can be improved.

Further, FIG. 6 also shows a toroidal type continuously variable transmission in which three power rollers 8 and 8 are provided between the input side disc and the output side disc in order to transmit a large torque. In the case of such a toroidal type continuously variable transmission, as is apparent from FIG. 6, three trunnions 6, 6 are provided.
Hydraulic cylinders 38a, 38a that constitute an actuator for displacing the are disposed in the outer peripheral portion. Therefore, if these hydraulic cylinders 38a, 38a are arranged so that the major axis direction of the oval or elliptical shape and the axial direction of the toroidal type continuously variable transmission (front and back directions in FIG. 6) are aligned, the toroidal type continuously variable transmission is performed. The capacity of the actuator can be sufficiently increased without increasing the outer dimensions of the machine.

Next, FIG. 7 shows a second embodiment of the present invention corresponding to claim 2. In the case of this embodiment, the drive piston 3 is located at two intermediate positions of a bolt 48, which is a rod member having one end coupled to the pivot 5 of the trunnion 6.
7b and 37b are fixed while being separated from each other in the axial direction. Then, the three fixing plates 41a, 41b, 41
The hydraulic cylinders 38b, 38b provided independently of each other on the inside of c are provided with respective drive pistons 37b, 3b.
7b is oil-tightly fitted. Each of these drive pistons 37
The outer peripheral surfaces of b and 37b and the inner peripheral surfaces 42 and 42 of the hydraulic cylinders 38b and 38b are circular in cross section.

The drive pistons 37b, 37
The pressure oil can be freely supplied to and discharged from the two pairs of chambers 45a and 45b, which are formed by partitioning the insides of the hydraulic cylinders 38b and 38b with oil-tightness by b. In the case of this embodiment, the drive pistons 37b, 37b are
Can rotate inside the respective hydraulic cylinders 38b, 38b, so that the thrust rolling bearing 51 as in the first embodiment described above can be rotated.
a and 51b (FIGS. 1 and 3) are not provided.

In the toroidal type continuously variable transmission constructed as described above, the drive pistons 37b, 37b and the hydraulic cylinders constituting the actuator are designed to increase the capacity of the actuator in order to support a large load applied to the trunnion 6. Even when the total cross-sectional area of 38b, 38b is sufficiently secured, the size of each of the hydraulic cylinders 38b, 38b in the diametrical direction can be reduced as a whole. As a result,
For example, when the toroidal type continuously variable transmission as shown in FIGS. 4 to 6 is incorporated, the outer dimensions of the toroidal type continuously variable transmission can be reduced to reduce the size of the toroidal type continuously variable transmission. The same operational effects as those of the above-described first embodiment can be obtained.

[0040]

Since the toroidal type continuously variable transmission of the present invention is constructed and operates as described above, it can be installed in a limited space by reducing the external dimensions, and the toroidal type continuously variable transmission can be installed. This can contribute to the practical application of the multi-stage transmission as a transmission for automobiles.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a first embodiment of the present invention with only a main part taken out.

2 is an AA view of FIG. 1 showing two examples of the shape of the piston.

FIG. 3 is an enlarged view of part B in FIG.

FIG. 4 is a partial cross-sectional view showing a first example of a specific structure incorporating the present invention.

5 is a sectional view taken along line CC of FIG.

FIG. 6 is a partial sectional view showing a second example of a specific structure incorporating the present invention.

FIG. 7 is a cross-sectional view showing a second embodiment of the present invention in a state where only essential parts are taken out.

FIG. 8 is a side view showing a basic configuration of a conventionally known toroidal type continuously variable transmission in a state of maximum deceleration.

FIG. 9 is a side view showing the same state at the time of maximum acceleration.

FIG. 10 is a cross-sectional view showing an example of a conventionally known specific structure.

11 is a cross-sectional view taken along the line DD of FIG.

[Explanation of symbols]

 1 Input Shaft 2 Input Side Disk 2a Inner Side Surface 3 Output Shaft 4 Output Side Disk 4a Inner Side Surface 5 Axis 6 Trunnion 7 Displacement Axis 8 Power Roller 8a Circumferential Surface 9 Pressing Device 10 Cam Plate 11 Cage 12 Roller 13, 14 Cam Surface 15 Input shaft 16 Needle bearing 17 Collar 18 Output gear 19 Key 20 Support plate 21 Support shaft 22 Pivot shaft 23 Circular hole 24, 25 Radial needle bearing 26 Thrust ball bearing 27 Thrust needle bearing 28 Cage 29 Ball 30 Outer ring 31 Race 32 Retainer 33 Needle 36 Drive rod 37, 37a, 37b Drive piston 38, 38a, 38b Hydraulic cylinder 39 Housing 40 Frame 41a, 41b, 41c Fixing plate 42 Inner peripheral surface 43 Circular hole 44 Seal ring 45a, 45b Chamber 46 Yen Pipe 47 Seal ring 8 bolts 49 threaded hole 50 sleeve 51a, 51b thrust rolling bearing 52 head 54 input shaft 55 sleeve 56 Output gear

Claims (2)

[Claims] 1. An input side disk having an inner side surface having a rotating arcuate concave curved surface, and an output side disk having an inner side surface facing the inner side surface of the input side disk having a rotating arcuate concave curved surface,
Each peripheral surface is made into a spherical convex surface, and a plurality of powers provided between both the input side and output side disks with the peripheral surface abutting the inner side surfaces of both the input side and output side disks. Rollers, and rotatably supporting each of these power rollers on their respective first halves, displacement shafts of the same number as the power rollers, and trunnions of the same number as the power rollers, supporting the base halves of these displacement shafts. , Pivot shafts provided at both ends of each of these trunnions and having their respective axial centers arranged in a twisted positional relationship with respect to the central axes of the input side and output side discs, and the trunnions described above in the axial direction of these pivot axes. In a toroidal-type continuously variable transmission equipped with an actuator for displacing the actuator, the actuator includes a fixed hydraulic cylinder and a drive piston that is oil-tightly fitted inside the hydraulic cylinder. Ton and a rod member that connects the drive piston to the pivot, and the inner peripheral surface of the hydraulic cylinder and the outer peripheral surface of the drive piston are oval or elliptical in cross section. Toroidal type continuously variable transmission. 2. An input side disk having an inner side surface having a rotating arcuate concave curved surface, and an output side disk having an inner side surface facing the inner side surface of the input side disk having a rotating arcuate concave curved surface,
Each peripheral surface is made into a spherical convex surface, and a plurality of powers provided between both the input side and output side disks with the peripheral surface abutting the inner side surfaces of both the input side and output side disks. Rollers, and rotatably supporting each of these power rollers on their respective first halves, displacement shafts of the same number as the power rollers, and trunnions of the same number as the power rollers, supporting the base halves of these displacement shafts. , Pivot shafts provided at both ends of each of these trunnions and having their respective axial centers arranged in a twisted positional relationship with respect to the central axes of the input side and output side discs, and the trunnions described above in the axial direction of these pivot axes. In a toroidal type continuously variable transmission including an actuator for displacing the rod member, the actuator includes a rod member whose one end is coupled to the pivot and a plurality of intermediate portions of the rod member. It is characterized by comprising a plurality of drive pistons which are axially separated from each other and fixed at certain positions, and a fixed hydraulic cylinder which is provided independently of each other and in which these drive pistons are oil-tightly fitted. Toroidal type continuously variable transmission.