JPH0727194A - Toroidal type continuously variable transmission - Google Patents

Abstract

PURPOSE:To provide a toroidal type continuously variable transmission to provide excellent control precision through simple constitution. CONSTITUTION:A toroidal type continuously variable transmission comprises a plurality of power rollers 35 installed between an input disc and an output disc; a support member consisting of a trunnion 44 to rotatably support the power roller 35; a hydraulic mechanism consisting of a hydraulic cylinder 52 to axially displace the support member; and a change gear ratio control valve 62 to feed a control oil pressure to the hydraulic mechanism. An eccentric cam 80 having a downward narrowed cam surface formed on a peripheral surface is attached to the support member of the power roller 35, and the working part of the gear change ratio control valve 62 is brought into direct contact with the cam surface of the eccentric cam 80.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a toroidal type continuously variable transmission in which a plurality of power rollers are installed between an input disk and an output disk.

[0002]

2. Description of the Related Art Conventionally, for example, JP-A-61-119865.
As disclosed in Japanese Patent Laid-Open Publication No. 2004-242242, a pair of power rollers are arranged between an input disk to which driving torque is input from an automobile engine and an output disk for outputting driving torque to the driving wheels. There is known a toroidal type continuously variable transmission that is configured to adjust a gear ratio by displacing a supporting member that rotatably supports an axial direction of the supporting member to change a tilt angle of a power roller.

The supporting member of the power roller is provided with a hydraulic mechanism having a hydraulic piston and the like, and a three-layer structure in which a sleeve and a spool are arranged in a valve body for supplying control hydraulic pressure to the hydraulic mechanism. The gear ratio control valve of is installed. At both ends of the gear ratio control valve, a stepping motor that executes a gear shift control by moving a sleeve provided in the sleeve in the axial direction, and a spool that moves in the axial direction of the valve corresponding to the gear shifting operation. And a feedback means for causing the feedback.

As shown in FIG. 9, the feedback mechanism includes a shaft member 93 protruding from a support member composed of a trunnion 92 for supporting the power roller 91, and the shaft member 9
The precess cam 94 attached to the lower end of the No. 3 and the first arm 96 that comes into contact with the cam surface 95 that is a tapered surface formed on the lower surface of the precess cam 94 and the tip of the spool 98 of the gear ratio control valve 97 that comes into contact with the cam. And a lever member (bell crank) 100 having a second arm portion 99. The up-and-down displacement of the shaft member 93 and the rotational displacement of the shaft member 93, which are generated in accordance with the shift operation, are transmitted to the spool 98 via the lever member 100.

[0005]

As described above, the structure in which the movement of the precess cam is transmitted to the operating member such as the spool of the gear ratio control valve by the lever member has a complicated structure and a high manufacturing cost. In addition, there is a problem that unnecessary hysteresis and hunting occur due to rattling of the contact portion between the trunnion shaft member and the gear ratio control valve actuating member, and the lever member, and control accuracy deteriorates.

The present invention has been made to solve the above problems, and provides a toroidal type continuously variable transmission that can simplify the configuration and can effectively improve the control accuracy. The purpose is to do.

[0007]

The invention according to claim 1 is
A plurality of power rollers installed between the input disk and the output disk, a support member for rotatably supporting the power rollers, a hydraulic mechanism for displacing the support members in the axial direction thereof, and a control by the hydraulic mechanism. In a toroidal type continuously variable transmission having a gear ratio control valve for supplying hydraulic pressure,
An eccentric cam having a downwardly constricted cam surface formed on the peripheral surface is attached to a supporting member of the power roller, and the operating portion of the gear ratio control valve is directly contacted with the cam surface of the eccentric cam. .

According to a second aspect of the present invention, in the toroidal type continuously variable transmission according to the first aspect, the operating portion of the gear ratio control valve is provided with a ball bearing portion that comes into contact with the cam surface of the eccentric cam. .

According to a third aspect of the present invention, in the toroidal type continuously variable transmission according to the first aspect, the eccentric cam is provided with an inner peripheral portion attached to a supporting member of the power roller, and a bearing on the inner peripheral portion. The outer peripheral portion is attached to the outer peripheral portion, and the cam surface is formed on the peripheral surface of the outer peripheral portion.

[0010]

According to the invention described in claim 1, when the transmission is operated, the operating member of the shift control valve is directly pushed by the cam surface of the eccentric cam, so that the feedback control is mechanically performed. Become.

According to the second aspect of the present invention, when the transmission is operated, the ball bearing portion provided on the operating member of the shift control valve is directly pushed by the cam surface of the eccentric cam, thereby mechanically operating. Will be feedback controlled.

According to the third aspect of the present invention, when the support member of the power roller is rotationally displaced during operation of the transmission,
In response to this, the inner peripheral portion of the eccentric cam is rotationally displaced, and the movement is transmitted to the outer peripheral portion of the eccentric cam via the bearing.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a schematic structure of a transmission of an automobile having a toroidal type continuously variable transmission to which a preload pressure adjusting method according to the present invention is applied. This transmission includes first and second power transmission paths 3 and 4 which are switched by a path switching clutch 2 connected to the output side of the engine 1.
have. The first power transmission path 3 transmits the engine output to the wheels via the speed reducer 7. In this embodiment, power is transmitted from the torque converter 5 to the wheels via the forward / reverse switching device 6 and the speed reducer 7. Is configured to communicate. The second power transmission path 4 transmits the engine output to the wheels via the toroidal type continuously variable transmission 8.

The torque converter 5 has an input shaft 5
pump cover 11 connected to a and this pump cover 11
A pump impeller 12 integrally formed with the turbine, a turbine liner 13 installed so as to face the pump impeller 12, and a hollow fixed shaft 15 between the turbine liner 13 and a one-way clutch 16.
And a stator 14 attached thereto. And
The input shaft 5a is connected to the output shaft of the engine 1, and the turbine shaft 17 serving as the output shaft of the torque converter 5 is connected to the turbine liner 13.
The space inside the pump cover 11 is filled with oil as a working fluid. A hollow rotary shaft 18 is connected to the pump impeller 12, and an oil pump 19 is attached to the rear end of the shaft 18.

The speed reducer 7 includes a turbine shaft 17
And two planetary gear mechanisms 20 and 21 for backward and forward movement, which are arranged coaxially with each other, and both planetary gear mechanisms 20 and 2 are provided.
The sun gear 22 commonly used by No. 1 is the turbine shaft 1
It is connected to 7. The reverse planetary gear mechanism 20 is
It is a single pinion type, and the rotation of the sun gear 22 is transmitted to the ring gear 25 via the pinion 24 supported by the carrier 23. The carrier 23 is connected to the hollow fixed shaft 15 and fixed to the casing 10. The ring gear 25 is connected to the output shaft 30 of the transmission via the reverse clutch 6a.

On the other hand, the forward planetary gear mechanism 21 is a double pinion type, and the rotation of the sun gear 22 is transmitted to the ring gear 28 via the inner pinion 26 and the outer pinion 27 supported by the carrier 23. Has become. The ring gear 28 is connected to the output shaft 30 via a forward clutch 6b and a one-way clutch 29.

The reverse clutch 6a and the forward clutch 6b constitute a forward / reverse switching device 6. When the reverse clutch 6a is engaged, the input from the turbine shaft 17 is transmitted to the output shaft 30 of the transmission via the reverse planetary gear mechanism 20.
When the forward clutch 6b is engaged, the input from the turbine shaft 17 is transmitted to the output shaft 30 via the forward planetary gear mechanism 21.

On the other hand, the toroidal type continuously variable transmission 8 of the second power transmission path 4 includes a pair of continuously variable transmission units 31, 32.
Both continuously variable transmission units 31, 3
2 is the output shaft 30 at a position adjacent to the speed reducer 7.
It is placed on top. The continuously variable transmission unit 31, 3
Reference numeral 2 has a pair of disks 33 and 34 which are spaced apart from each other in the axial direction, and a pair of power rollers 35 which are arranged between these disks 33 and 34 and are in sliding contact with both disks 33 and 34. is doing. Both power rollers 35
Are installed to face each other with the output shaft 30 interposed therebetween.

One disc (output disc) 33 of the pair of discs is fixed to the output shaft 30.
The other disc (input disc) 34 is the output shaft 30.
It is supported so as to be rotatable relative to and axially movable. The power roller 35 is configured such that the tilt angle θ is changed by a hydraulic mechanism described later, and the gear ratios of the toroidal type transmission units 31 and 32 are changed accordingly.

That is, the speed ratio when the rotation of the input disk 34 is transmitted to the output disk 33 via the power roller 35 is as follows.
Is set in accordance with the ratio of the radius Ri of the portion slidingly contacting the disk to the radius Ro of the portion slidingly contacting the output disk 33, so that when the power roller 35 tilts and the sliding contacting point is displaced,
In response to this, the toroidal type continuously variable transmission unit 3
The gear ratios of 1 and 32 are changed.

The structure of the transmission units 31, 32 of the toroidal type continuously variable transmission 8 will be described with reference to FIGS. The output disc 33 of one of the transmission units 31 is spline-fitted to the output shaft 30 of the transmission, and the bearing 37 is attached to the output disc 30 while being positioned by a ring-shaped positioning member 36 provided on the output shaft 30. It is rotatably supported by the transmission case 38 via the. The output disc 33 of the other transmission unit 32 is positioned by a bearing 37 that is locked to a step formed on the output shaft 30 of the transmission.

An input cam 38, which is supported so as to be rotatable relative to the input disks 34 constituting the transmission units 31 and 32, is disposed between the input disks 34. The input cam 38 and the input disk 34
Between the cam roller 40 held by the retainer 39 and
Is installed. The cam roller 40 contacts the cam surfaces formed on the input disk 34 and the input cam 38, respectively, and transmits the driving torque input to the input cam 38 to the output disk 33 via the input disk 34 and the power roller 35. Is configured to.

Further, the support member 4 for supporting the input disc 34 of the transmission unit 32 and the input cam 38.
An urging member 42, which is a disc spring for urging the input disks 34 of both transmission units 31 and 32 toward the output disk 33, is installed between the first and second transmission units 31 and 32.
A preload pressure is applied between the input disk 34 and the output disk 33 according to the urging force of.

Further, the transmission units 31, 32 are provided with a trunnion 44 having an eccentric shaft 43 for rotatably supporting the power roller 35. The trunnion 44 has a shaft member 45 protruding downward. It is installed. The trunnion 44 has its upper end supported by the upper surface of the transmission casing 38 via a spherical bush 46 and a connecting member 47 supporting the spherical bush 46, and its lower end supports the spherical bush 48 and its support. It is supported by a partition wall 51 provided at the lower end of the transmission case 38 via a connecting member 49 and a support shaft 50.

A hydraulic cylinder 52 for operating the trunnion 44 is provided in the partition wall 51.
The hydraulic cylinder 52 has a pair of upper and lower hydraulic pressures defined by a pair of upper and lower pistons 53 and 54 supported by the shaft member 46 of the trunnion 44 and a wall plate 55 located between the pistons 53 and 54. It has chambers 56 and 57. When the hydraulic pressure is introduced into the upper hydraulic chamber 56, the trunnion 44 is pushed up by the upper piston 53, and when the hydraulic pressure is introduced into the lower hydraulic chamber 57, the trunnion 44 is pushed down by the lower piston 54. The power roller 35 is tilted accordingly.

A positioning hole 59 is formed in the central portion of the upper connecting member 47 so that a supporting shaft 58 projecting from the transmission case 22 and a supporting member 59 fitted onto the supporting shaft 58 can be installed. In addition, a positioning hole 61 is formed in the central portion of the lower connecting member 49, in which the spherical bearing 60 fitted on the support shaft 50 is installed. Also, both pistons 5
A lubricating oil supply port 55a communicating with a lubricating oil passage 45a provided in the shaft member 45 is formed in the partition wall plate 55 between the shafts 3 and 54. Then, the lubricating oil is led from the lubricating oil passage 45a to the oil passage 44a formed in the trunnion 44, so that the support portion of the power roller 35 is lubricated.

Hydraulic chambers 56 and 57 of the hydraulic cylinder 52.
As shown in FIG. 4, a gear ratio control valve 62 that controls a gear ratio by controlling the supply and discharge of hydraulic pressure to and from a valve body 64 attached to the lower surface of a housing 63,
A sleeve 65 fitted in the valve body 64,
A three-layer structure having a spool 66 slidably supported in the sleeve 65 is formed. At one end of the spool 66, a spring 67 that constitutes a control actuator, a rotating member 68, and a pin member 69.
And a stepping motor 70 are provided, and the spool 6
Mechanical feedback means 71 is installed at the other end of 6.

A source pressure receiving port P1, a shift-up control port P2, and a shift-down control port P3 are formed in the valve body 64, and the sleeve 67 has the ports P1 to P3. A main port 72, a first port 73, and a second port 74 that are in constant communication with each other are formed at corresponding positions.

Further, the spool 66 is formed with an annular groove 75 which is in constant communication with the main port 72, and first and second land portions 76 and 77 located on the left and right sides thereof. The above first and second land portions 76, 77
Is configured to close the first and second ports 73 and 74, respectively, during non-shifting in which neither upshifting nor downshifting is performed.

A rotary member 68 is attached to the drive shaft of the stepping motor 70, and a collar 78 is screwed onto the tip of the rotary member 68. A pin member 69 is locked to the collar 78, and both ends of the pin member 69 are locked to grooves (not shown) formed in the valve body 64, so that the collar 78 is The rotation is blocked. And
When the rotating member 68 is rotationally driven by the stepping motor 70, the collar 78 moves in its axial direction, and along with this, the sleeve 65 is slidably driven in the axial direction via the pin member 69. It is configured.

In response to the sliding displacement of the sleeve 65, the main port 72 of the sleeve 65 and the first port 73 of the valve body 65 via the groove 75 of the spool 66.
Alternatively, the source pressure receiving port P1 is communicated with the second port 74.
The shift control is executed by deriving the internal hydraulic pressure to the shift-up control port P2 or the shift-down control port P3.

The feedback means 71 is provided at the shaft member 45 projectingly provided on one trunnion 44, the recess cam 80 attached to the lower end thereof, and the tip of the spool 66 of the speed ratio control valve 62. It has a ball bearing portion 81. The precess cam 80 is composed of an eccentric cam having a downwardly constricted cam surface 82 formed on the peripheral surface thereof, and as shown in FIG. 5, the shaft member 45 is attached at a position offset from the central portion to one side. The ball bearing 81 provided at the tip of the spool 67 is pressed against the cam surface 81 of the recess cam 80 by the urging force of the spring 67 installed in the sleeve 65 of the gear ratio control valve 62. There is.

In the above configuration, when the stepping motor 70 is rotationally driven at an angle corresponding to the target tilt angle (target gear ratio) in response to a control signal output from a control unit (not shown) during gear shifting, this rotation angle The sleeve 65 moves in the axial direction by an amount corresponding to. As a result, the main port 72 of the sleeve 65 is
6 through the groove 75 to communicate with the first port 72 or the second port 74 of the valve body 65, whereby the hydraulic pressure is supplied to the predetermined hydraulic chambers 56, 57 and the power roller 35 is displaced to the target tilt angle. .

For example, when shifting up, when the stepping motor 70 rotates forward by a predetermined angle in response to the control signal, the sleeve 65 moves to the tip side, that is, the side where the feedback means 71 is installed. As a result, the main port 72 communicates with the first port 73 via the groove 75, the hydraulic pressure of the source pressure receiving port P1 is output to the shift-up port P2, and the shift-down port P3.
Is connected to the drain port, and this downshift port P
The hydraulic pressure in 3 is relieved.

Then, in accordance with the above hydraulic pressure, the hydraulic cylinder 5
By operating 2, the trunnion 44 and the shaft member 45 that support the power roller 35 are moved up and down, the power roller 36 is tilted accordingly, and the toroidal transmission 6 shifts to the speed increasing side. It has become.

On the other hand, at the time of downshifting, the stepping motor 70 reversely rotates by a predetermined angle according to the control signal, and the sleeve 65 moves to the base end side, that is, the installation side of the stepping motor 70. As a result, the main port 72 communicates with the second port 74 via the groove 75, the hydraulic pressure of the source pressure receiving port P1 is output to the shift down port P3, and the shift up port P is generated.
2 communicates with the drain port, and the hydraulic pressure in the shift-up port P2 is relieved.

Then, in accordance with the above hydraulic pressure, the hydraulic cylinder 5
When 2 is operated, the trunnion 44 and the shaft member 45 are displaced up and down in the opposite direction to the above-described upshift, and the power roller 36 is tilted accordingly and the toroidal transmission 6 shifts to the deceleration side. At the time of this downshift, the sleeve 65 is biased toward the tip end side by the spring 67, so that the biasing force causes the sleeve 65 to move quickly and the shift responsiveness is ensured.

When the trunnion 44 and the shaft member 45 are rotated in response to the rotation of the power roller 35, the precess cam 80 is rotated accordingly. The ball bearing 81 provided at the tip of the spool 66 slides in the circumferential direction along the cam surface 82 by the rotation of the recess cam 80, and the spool 66 moves in the same direction as the moving direction of the sleeve 65. Slide driven. Also,
When the recess cam 80 is displaced up and down in response to the vertical displacement of the shaft member 45, the tip of the spool 66 is pushed by the recess cam 80, sliding along the cam surface 82 in the up and down direction, and the spool 66 moves. Slide driven.

When the tilt angle of the power roller 35 reaches the target tilt angle, the movement amount of the spool 66 becomes equal to the movement amount of the sleeve 65, and the main port 72 is moved.
Then, the communication with the first port 73 or the third port 74 is blocked. As a result, the supply of hydraulic pressure to the hydraulic chambers 56 and 57 is stopped, the change of the tilt angle is prevented, and the power roller 35 is held at the target tilt angle.

As described above, the tip of the spool 66, which constitutes the operating member of the gear ratio control valve 62, is brought into contact with the cam surface 82 of the recess cam 80 attached to the shaft member 45 projecting from the trunnion 44. Since the spool 66 is directly driven by the recess cam 80,
It is possible to simplify the configuration of the feedback control means 71 and reduce its weight.

Further, according to the above-mentioned structure, the lever member and each portion abutting against the lever member, as in the conventional device in which the driving force of the recess cam is transmitted to the operating member of the gear ratio control valve through the lever member. Since there is no rattling between and, it is possible to effectively prevent the occurrence of unnecessary hysteresis and hunting, stabilize the control state, and improve the control response.

Further, in the above embodiment, the ball bearing portion 81 provided at the tip of the spool 66 is attached to the precess cam 8.
Since it is configured to come into contact with the cam surface 82 of No. 0, the spool 66 is slid along the cam surface 82 by sliding the ball bearing portion 81 smoothly.
It is possible to properly follow up and down and rotation operations of 0.

As shown in FIG. 6, a disc-shaped inner peripheral portion 83 eccentrically fixed to the shaft member 45 and the inner peripheral portion 83.
A precess cam 80 composed of an annular outer peripheral portion 85 attached via a bearing 84 to the outer peripheral portion 8
The tip of the spool 66 may be brought into contact with the cam surface 82 formed on the peripheral surface of the spool 5. According to this configuration, when the shaft member 45 is rotationally displaced, the outer peripheral portion 85
The spool 66 can be operated smoothly by moving it horizontally without rotating it. Therefore, the ball bearing 81 provided at the tip of the spool 66 can be omitted.

As shown in FIG. 7, when the gear ratio control valve 62 is installed along the central portion of the shaft member 45 of the trunnion 44 facing each other, the hydraulic piston 52 provided at the installation portion of the shaft member 45. In order to avoid interference with the gear ratio control valve 62, the recess cam 80 and the gear ratio control valve 62 need to be arranged offset below the installation portion of the hydraulic piston 52.

Further, in order to prevent the hydraulic piston 52 and the gear ratio control valve 62 from interfering with each other without offsetting the gear ratio control valve 62 downward, as shown by a solid line or an imaginary line in FIG. , Shaft members 45 facing each other
The shift control valve 62 may be arranged in a state of being offset to the side of the line α connecting the central portions of the.

[0046]

As described above, according to the present invention, the operating member of the gear ratio control valve is brought into contact with the cam surface of the eccentric cam attached to the supporting member of the power roller, and the spool is directly moved by the eccentric cam. Because it was configured to drive,
It is possible to simplify the configuration of the mechanical feedback control means that feedback-controls the gear ratio control valve and reduce its weight. Further, unlike the case where the lever member is provided between the eccentric cam and the operating member of the gear ratio control valve, rattling does not occur, so that unnecessary hysteresis and hunting are effectively prevented. However, there is an advantage that a stable control state can be obtained and the control response can be improved.

If a ball bearing portion is provided at the tip of the operating member of the gear ratio control valve and the ball bearing portion is brought into contact with the cam surface of the eccentric cam, the ball bearing portion is Since it can be slid smoothly along the cam surface, it can be operated by appropriately following the eccentric cam of the operating member.

Further, the eccentric cam is composed of an inner peripheral portion fixed to the support member and an outer peripheral portion attached to the inner peripheral portion via a bearing, and a cam formed on the peripheral surface of the outer peripheral portion. When the tip of the actuating member is brought into contact with the surface, the actuating member is moved by the cam surface of the saw outer circumference without rotating the outer circumference according to the rotational displacement of the support member. Since it can be operated, there is an advantage that this operation member can be operated smoothly.

[Brief description of drawings]

FIG. 1 is a schematic explanatory diagram showing an overall configuration of a transmission equipped with a toroidal type continuously variable transmission according to an embodiment of the present invention.

FIG. 2 is a front sectional view showing a specific example of the toroidal transmission.

FIG. 3 is a side sectional view of the toroidal transmission.

FIG. 4 is a side sectional view showing a configuration of a transmission control valve.

FIG. 5 is a bottom view showing the configuration of the eccentric cam.

FIG. 6 is a cross-sectional view showing another example of an eccentric cam.

FIG. 7 is a bottom view showing an example of installation of a transmission control valve.

FIG. 8 is a bottom view showing another installation example of the transmission control valve.

FIG. 9 is a perspective view showing a conventional example.

[Explanation of symbols]

 8 Toroidal Type Continuously Variable Transmission 33 Output Disc 34 Input Disc 35 Power Roller 44 Trunnion (Supporting Member) 60 Gear Ratio Control Valve 66 Spool (Operating Member) 80 Eccentric Cam (Precess Cam) 81 Ball Bearing 82 Cam Surface 83 Inner Circumference 84 Bearing 85 outer periphery

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Seiji Ezaki 3-1, Shinchi, Fuchu-cho, Aki-gun, Hiroshima Mazda Motor Corporation

Claims (3)

[Claims] 1. A plurality of power rollers installed between an input disk and an output disk, a support member for rotatably supporting the power rollers, and a hydraulic mechanism for displacing the support members in the axial direction thereof. In a toroidal type continuously variable transmission having a speed ratio control valve that supplies control hydraulic pressure to this hydraulic mechanism, an eccentric cam having a cam surface with a downward constriction formed on its peripheral surface is attached to a support member of the power roller, A toroidal-type continuously variable transmission characterized in that the operating portion of the gear ratio control valve is directly brought into contact with the cam surface of the eccentric cam. 2. The toroidal type continuously variable transmission according to claim 1, wherein the operating portion of the gear ratio control valve is provided with a ball bearing portion that abuts on the cam surface of the eccentric cam. 3. An eccentric cam is composed of an inner peripheral portion attached to a supporting member of a power roller and an outer peripheral portion attached to the inner peripheral portion via a bearing, and a cam surface is formed on a peripheral surface of an outer member. The toroidal type continuously variable transmission according to claim 1, wherein: