JP3235518B2 - Hydraulic switching device for friction wheel type continuously variable transmission - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic switching device for switching a supply pressure to a servo piston for controlling a speed change of a friction wheel type continuously variable transmission by moving the vehicle forward and backward.

[0002]

2. Description of the Related Art A friction wheel type continuously variable transmission is realized by making a power roller frictionally engaged between an input and output disk into a stroke by a servo piston and tilting the power roller on the input and output disk surface. The speed change is performed steplessly. Therefore, when the rotation of the input / output disk is switched between forward rotation and reverse rotation, the tilt of the power roller needs to be reversed.
As described in Japanese Patent Publication No. 3562, there is proposed a hydraulic switching device including a forward / backward hydraulic switching valve having two control valves, and switching a supply pressure to a servo piston in accordance with forward or reverse rotation of a counter shaft. ing.

FIG. 8 is a partial cross-sectional view illustrating a friction wheel type continuously variable transmission. The servo piston 10 is housed in the cylinder body 1, and the cylinder body 1 has two members 1.
a and 1b are united. The valve body 5 is
It consists of an upper body 5a and a lower body 5b. The upper body 5a accommodates a forward / backward hydraulic switching valve B for switching the supply pressure to the servo piston 10 in accordance with the forward / backward travel of the vehicle. This is done by moving. Cylinder body 1
A countershaft 2 that is offset with respect to the input / output shaft of the friction wheel type continuously variable transmission is disposed between the valve shaft 5 and the one-way clutch C.
Attach the arm member 3 via o.

The forward / backward hydraulic switching valve B has, for example, a control valve for forward traveling and a reverse traveling, as described in Japanese Patent Application Laid-Open No. Hei 2-163562, and responds to forward or reverse rotation of a counter shaft. Thus, the supply pressure to the servo piston 10 is switched. For simplicity of description, the forward / backward hydraulic switching valve B has at least an upper body 5a provided with a spool 4, one end of which is supported by a spring 7 and the other end is pressed by an arm member 3. And

When the vehicle advances (countershaft 2 rotates forward), the one-way clutch Co rotates together with the countershaft 2 to the side where the one-way clutch Co idles on the countershaft 2 (arrow F), and the arm member 3 moves to the spool 4. Release the pressure. Thereby, the forward / backward hydraulic switching valve B switches the supply pressure to the servo piston 10 so that the speed change control during forward movement can be performed.

The arm member 3 locks the one-way clutch Co together with the counter shaft 2 when the vehicle moves backward (counter shaft 2 rotates backward) (arrow L).
To press the spool 4. As a result, the forward / backward hydraulic switching valve B switches the supply pressure to the servo piston 10 so that the speed change control during reverse travel can be performed.

That is, the arm member 3 functions as a forward / reverse switching sensor, and when the vehicle is moving forward, the arm member 3 releases the pressing of the forward / backward hydraulic switching valve B against the spool 4 so that the servo piston moves forward. When the vehicle travels backward, the arm member 3 presses the spool 4 to supply hydraulic pressure for reverse travel to the servo piston, thereby enabling speed change control corresponding to forward and backward travel of the vehicle.

FIG. 9 is a schematic view showing the friction wheel type continuously variable transmission shown in FIG. This figure shows a state in which the cylinder body 1 and the valve body 5 are assembled in a transmission case 6. When this transmission is mounted on a vehicle, the transmission case 6
Is sealed with an oil pan 8 (not shown), and is arranged as shown in FIG.

As is apparent from FIGS. 8 and 9, the hydraulic switching device of the friction wheel type continuously variable transmission generally has a servo piston 10
In order to prevent the reaction force of the hydraulic pressure acting on the cylinder body 1 from affecting the valve body 5 via the cylinder body 1, the cylinder body 1 and the valve body 5 are separated from each other, and the cylinder body 1 of the servo piston 10 and the valve are separated. This is a layout in which the body 5 is separated. Incidentally, such a conventional example is described in, for example, Japanese Patent Application Laid-Open No. 4-29659.

For this reason, the transmission case 6 is assembled into the cylinder body 1, the counter shaft 2, the valve body 5,
Assemble in order. In addition, the valve body 5 has a recess 5i.
A stopper S is provided on the side surface of the portion. When the arm member 3 comes into contact with the stopper S, the arm member 3 idles on the counter shaft 2 by the one-way clutch Co.

[0011]

As shown in FIGS. 8 and 9, when the cylinder body 1 and the valve body 5 are formed separately and mounted on the transmission case 6, a recess 5i provided in the valve body 5 is provided. First, the arm member 3 must be stored.

However, since the arm member 3 is mounted on the countershaft 2 via the one-way clutch Co, when the valve body 5 is mounted on the transmission case 6, the mounting angle of the arm member 3 cannot be restricted. Therefore, before assembling the valve body 5, the operator must adjust the arm angle in advance by a certain amount, but this operation is very difficult. For this reason, for example, it is conceivable to make the recess 5i large in the spool axis direction to facilitate the assembly. However, since the arm angle β from the stopper S to the spool 4 becomes large, a time lag occurs when switching from forward to reverse. As a result, a gear ratio deviation occurs.

After the valve body 5 is assembled,
The arm member 3 is hidden behind the valve body 5 and cannot be seen.
Therefore, it is not possible to confirm whether or not the arm member 3 is in a correct position at the time of assembling, and it is difficult to adjust the arm member while assembling or after assembling. For this reason, it is conceivable to provide an opening in the valve body 5 and adjust the arm member 3 visually therefrom, but this is not preferable because it is necessary to change the oil passage layout in the valve body 5.

SUMMARY OF THE INVENTION An object of the present invention has been made in view of the above-mentioned facts, and facilitates adjustment of an arm member which becomes invisible when assembling a valve body of a forward / reverse hydraulic directional control valve. To improve the performance.

[0015]

SUMMARY OF THE INVENTION To this end, a hydraulic switching device for a friction wheel type continuously variable transmission according to the present invention, which is the present invention, controls the speed change of a friction wheel type continuously variable transmission. A cylinder body of a servo piston, a valve body of a hydraulic switching valve for forward / backward movement that switches supply pressure to the servo piston in accordance with forward / backward movement of the vehicle by pressing a spool, a cylinder body of the servo piston, and the forward / backward movement. An arm member which is rotatably fitted via a one-way clutch to a counter shaft between the valve bodies of the hydraulic switching valve, and the arm member is moved forward and backward by turning the one-way clutch on the locking side. Of the hydraulic switching valve for forward and backward movement by rotating the arm member on the side on which the one-way clutch idles on the counter shaft. In a hydraulic pressure switching device for a friction wheel type continuously variable transmission that switches a supply pressure to the piston by releasing a pressure on a pool, a stopper that restricts rotation of the arm member on the idling side is provided on a cylinder body of the servo piston. Is provided.

According to a second aspect of the present invention, in the hydraulic switching device for the friction wheel type continuously variable transmission according to the second aspect, an elastic member for elastically supporting the arm member at a rotation limit position on the idling side is added to the first aspect. It is characterized by having been provided.

According to a third aspect of the present invention, there is provided a hydraulic switching device for a friction wheel type continuously variable transmission, wherein the elastic member is a tension element.

According to a fourth aspect of the present invention, there is provided a hydraulic switching device for a friction wheel type continuously variable transmission, wherein the elastic member is a pressing element in the second aspect.

According to a fifth aspect of the present invention, there is provided a hydraulic switching device for a friction wheel type continuously variable transmission according to the first or fourth aspect, wherein the lock side rotation of the arm member is provided on the cylinder body of the servo piston. A stopper for restricting the pressure is provided.

According to a sixth aspect of the present invention, there is provided a hydraulic switching device for a friction wheel type continuously variable transmission, comprising: a cylinder body of a servo piston which controls a speed change of the friction wheel type continuously variable transmission; A valve body of a forward / backward hydraulic switching valve for switching the supply pressure to the piston in response to forward / backward travel of the vehicle by pressing a spool, and a counter shaft between the cylinder body of the servo piston and the valve body of the forward / backward hydraulic switching valve. And an arm member that is rotatably fitted via a one-way clutch to the arm member.
When the one-way clutch locks, the arm member is pressed against the spool of the forward / reverse hydraulic switching valve, and the arm member is rotated by the one-way clutch idling on the counter shaft. In a hydraulic switching device for a friction wheel type continuously variable transmission, which switches a supply pressure to the piston by releasing the pressing of a hydraulic switching valve against a spool, a valve body of the cylinder body of the servo piston and the hydraulic switching valve for forward and backward movement is provided. A stopper is provided on a partition wall of a transmission case for housing the body, the stopper restricting rotation of the arm member on the idling side.

Further, according to claim 7, which is the present invention,
The hydraulic switching device of the friction wheel type continuously variable transmission is characterized in that, in claim 6, the partition wall of the transmission case is a gear housing that houses an output gear that transmits power from an output disk to a counter shaft. Is what you do.

[0022]

As described above, the hydraulic switching device of the friction wheel type continuously variable transmission according to the first aspect of the present invention has an arm mounted on a cylinder body of a servo piston assembled earlier than a valve body. Since the stopper for restricting the rotation of the member on the idling side is provided, the arm member can be positioned by the stopper before the valve body is assembled. Therefore, the angle adjustment of the arm member is facilitated, and assembling workability is improved. Further, the arm angle can be finely adjusted by changing the stopper.

According to a second aspect of the present invention, in the hydraulic switching device for the friction wheel type continuously variable transmission according to the first aspect, an elastic member for elastically supporting the arm member at a rotation limit position on the idling side is added to the first aspect. With this arrangement, the positioning of the arm member performed by the stopper is further stabilized.

According to a third aspect of the present invention, in the hydraulic pressure switching device for a friction wheel type continuously variable transmission, since the elastic member is a tension element in the second aspect, the function and effect according to the second aspect are easily achieved. Is obtained.

According to a fourth aspect of the present invention, in the hydraulic pressure switching device for a friction wheel type continuously variable transmission, since the elastic member is a pressing element in the second aspect, the same operation and effect as in the third aspect are provided. Is obtained.

According to a fifth aspect of the present invention, in the hydraulic switching device for a friction wheel type continuously variable transmission according to the first or the fourth aspect, the cylinder body of the servo piston is provided with a rotation of the arm member on the lock side. Is provided, the same operation and effect as in claim 2 can be obtained.

According to the hydraulic switching device of the friction wheel type continuously variable transmission according to the present invention, the transmission houses the cylinder body of the servo piston and the valve body of the hydraulic switching valve for forward / reverse travel. Since the stopper that regulates the rotation of the arm member on the idling side is provided on the partition wall of the case, the same operation and effect as the first aspect can be obtained.

Further, according to claim 7, which is the present invention,
According to the hydraulic switching device for the friction wheel type continuously variable transmission, claim 6 is provided.
In the above, since the partition wall of the transmission case is a gear housing for accommodating an output gear, the operation and effect of claim 1 can be achieved without having to change a conventionally used case, thereby increasing production costs. Can be suppressed.

[0029]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A hydraulic switching device for a friction wheel type continuously variable transmission according to the present invention will be described in detail with reference to the accompanying drawings. The following description is based on the above-cited references JP-A-2-163562 and JP-A-4-29659.

FIG. 1 is a partial cross-sectional view showing the first embodiment of the present invention viewed from the axial direction of an input / output disk. However, when this transmission is mounted on a vehicle, the upper opening of the transmission case 6 is sealed with an oil pan 8, and the transmission case 6 is arranged upside down in the drawing. FIG. 2 is a schematic diagram showing the first embodiment of FIG. In FIG. 2, the same parts as those in FIG.

Hereinafter, a first embodiment of the present invention will be described in detail with reference to FIGS. Inside the transmission case 6, first, the cylinder body 1 of the servo piston 10 which controls the shift control of the toroidal-type continuously variable transmission is mounted, and then, the countershaft having an offset arrangement for transmitting power from an output disk (not shown). Attach 2. The countershaft 2 is described in Japanese Patent Laid-Open No. 2-163.
As disclosed in Japanese Patent Publication No. 562, the arm member 3 is fitted so as to be relatively rotatable via a one-way clutch Co.

Reference numeral 5 denotes a valve body provided with various control valves and oil passages, which is constituted by combining an upper body 5a and a lower body 5b.
Is performed after the arm member 3 is mounted.

The servo piston 10 is housed in the cylinder body 1, and this cylinder body 1 has two members 1a,
1b. In this embodiment, in order to prevent the reaction force of the hydraulic pressure acting on the servo piston 10 from affecting the valve body 5, the cylinder body 1 is separated from the valve body 5, and the cylinder body 1 of the servo piston 10 is separated from the cylinder body 1. And the valve body 5 as a separate body.

The forward / backward hydraulic switching valve B for switching the supply pressure to the servo piston 10 in accordance with the forward / backward movement of the vehicle is housed in the upper body 5a of the valve body 5. Switching is performed by moving the spool 4. The forward-backward hydraulic switching valve B is disclosed in
As shown in Japanese Patent No. 163562, a control valve for forward traveling and reverse traveling is provided, and the supply pressure to the servo piston is switched according to forward or reverse rotation of the counter shaft. In order to simplify the explanation, the forward / backward hydraulic switching valve B has at least an upper body 5a provided with a spool 4, one end of which is supported by a spring 7 and the other end is pressed by an arm member 3. And

When the vehicle moves forward (countershaft 2 rotates forward), the arm member 3 moves to the one-way clutch Co.
To rotate in the direction of the arrow F integrally with the counter shaft 2 via the, and does not press the spool 4. However, when the arm member 3 comes into contact with the side surface of the depression 5i and the reaction force in the arrow direction L acts on the arm member 3 by a predetermined amount or more by the one-way clutch Co, the rotation of the counter shaft 2 It turns into an idling above. Further, when the vehicle moves backward (counter shaft 2 rotates reversely), arm member 3 rotates integrally with counter shaft 2 in the direction of arrow L with one-way clutch Co locked, and pushes spool 4. Note that the arm member 3 is the same as that described in Japanese Unexamined Patent Application Publication No.
As disclosed in JP-A-163562, one-way clutch Co
And the arm member 3
Is pressed when the spool 4 is pressed to overcome the frictional force with the one-way clutch Co.

That is, the arm member 3 serves as a switching sensor, and when the vehicle moves forward, the arm member 3 rotates together with the counter shaft 2 in the direction of arrow F to the spool 4 of the forward / backward hydraulic switching valve B. By releasing the pressing of
The forward / backward hydraulic switching valve B is switched so that the control pressure of a forward control valve (not shown) can be supplied to the servo piston 10. When the vehicle moves backward, the arm member 3 moves together with the counter shaft 2 in the direction of the arrow. By turning to L and pushing the spool 4, the forward / backward hydraulic switching valve B can be switched so that the control pressure of the reverse control valve (not shown) can be supplied to the servo piston 10. As a result, the servo piston 10 housed in the cylinder body 1 strokes by an amount necessary for shifting, thereby enabling shift control of the friction wheel type continuously variable transmission.

However, in order to protect the valve body 1, when the cylinder body 1 and the valve body 5 are separately formed and attached to the transmission case 6 as disclosed in Japanese Patent Application Laid-Open No. Hei 4-29659, the valve body 5 is provided on the valve body 5. The arm member 3 must be accommodated in the recess 5i. However, when assembling the valve body 5,
Since the mounting angle of the arm member 3 is not restricted,
There is a problem that workability when assembling the valve body 5 is deteriorated.

Therefore, in this embodiment, as shown in FIGS. 1 and 2, a stopper S1 is provided on the cylinder body 1 to restrict the range in which the arm member 3 can rotate in the direction of the arrow F, and before the valve body 5 is assembled. Arm member 3 with stopper S
1 enables positioning on the cylinder body 1.

The arm member 3 has a protruding portion 3p. When the bottom surface of the protruding portion 3p contacts the stopper S1, the arm member 3 rotates together with the counter shaft 2 in the direction of arrow F. Can be regulated.

Therefore, according to the present invention, the valve body 5
Since the arm member 3 can be positioned by the stopper S1 before assembling, the angle adjustment of the arm member 3 is facilitated and the assembling workability is improved. in addition,
According to the present invention, since it is not necessary to adjust the angle of the arm member 3 while assembling the valve body 5 or after assembling, for example, an opening for visually checking the arm member 3 in the valve body 5 having a complicated structure. There is no need to make any design changes such as providing parts. Further, if the position and shape of the stopper S1 are changed, as shown in FIG.
Can be fine-tuned. That is, the arm angle α from the position regulated by the stopper S1 to the contact with the spool 4 can be reduced as compared with the conventional example shown in FIG. Therefore, a time lag does not occur at the time of switching due to an increase in the arm angle, so that a shift in the gear ratio does not occur.

FIG. 3 is a partial sectional view showing the second embodiment of the present invention viewed from the axial direction of the input / output disk. In this embodiment, there is provided an elastic member 11 for elastically supporting the arm member 3 at the rotation limit position on the idling side. At this time, the elastic member 11
Is a tension spring for preventing the arm member 3 from rotating due to friction generated at the time of assembling the valve body 5 or contact with another member. This tension force is generated when the one-way clutch Co idles on the counter shaft 2. In the direction of arrow F. However, the spring constant of the tension spring 11 is set so that the tension force can be made sufficiently smaller than the torque limiter force (valve driving force), that is, the force required to drive the spool 4.

In the second embodiment, the provision of the tension spring 11 for elastically supporting the arm member 3 at the idling-side rotation limit position further stabilizes the positioning of the arm member 3 performed by the stopper S1.

FIG. 4 is a partial sectional view showing the third embodiment of the present invention viewed from the axial direction of the input / output disk. In this embodiment, together with the stopper S1, a stopper S2 is provided on the lock side of the arm member 3 on which the arm member 3 rotates integrally with the counter shaft 2, that is, on the arrow L side.

The arm member 3 has a projection 3po together with the projection 3p. The contact between the bottom surface of the protruding portion 3po and the stopper S2 prevents the arm member 3 from rotating together with the counter shaft 2 in the direction of the arrow L, and moves the arm member 3 from before the valve body 5 is assembled. Positioning can be performed by the stopper S1.

Therefore, in the third embodiment, since the rotation on the idling side of the arm member 3 is restricted and the rotation on the lock side of the arm member 3 is also restricted, the operation and effect obtained in the first embodiment are more remarkable. Become something.

FIG. 5 is a partial sectional view showing the fourth embodiment of the present invention viewed from the axial direction of the input / output disk. In this embodiment, an elastic member 12 that elastically supports the arm member 3 at the rotation limit position on the idling side is provided. At this time, the elastic member 12
Is a compression spring for preventing the arm member 3 from rotating due to friction generated at the time of assembling the valve body 5 or contact with another member. The repulsive force of the spring 12 is such that the arm member 3 is driven by the one-way clutch Co. As a result, it acts as a pressing force in the direction of arrow F that runs idle on the counter shaft 2. However, the spring constant of the compression spring 12 is set so that the pressing force in the direction of arrow F can be made sufficiently smaller than the torque limiter force (valve driving force), that is, the force required to drive the spool 4.

Therefore, in the fourth embodiment provided with the compression spring 12 for elastically supporting the arm member 3 at the idling-side rotation limit position,
The same operation and effect as in the second embodiment can be obtained. If the compression spring 12 is used together with the stopper S2 for restricting the rotation of the arm member 3 on the lock side described in the third embodiment, the effect is more remarkable.

FIG. 6 is a schematic view showing the fifth embodiment of the present invention viewed from the axial direction of the input / output disk. The arm member 3 is provided on a partition wall 6w of a transmission case 6 accommodating the cylinder body 1 and the valve body 5. Is provided with a stopper S3 for restricting rotation in the arrow direction F. FIG. 7 is a partial sectional view of FIG. 6 viewed from the direction of arrow D, and a hole H is a portion through which the stroke axis of the servo piston 10 penetrates.

Since the stopper S3 is provided on the partition wall 6w, the same operation and effect as in the case where the stopper S1 is provided on the cylinder body 1 can be obtained with respect to the positioning of the arm member 3 and the adjustment of the arm angle α.

It is common practice to house an output gear (not shown) for transmitting the power from the output disk to the countershaft 2 in a gear housing integral with the transmission case 6. Therefore, if this gear housing is used for the partition wall 6w, the stopper S3 can be provided without changing the transmission case 6 conventionally used, and the increase in production cost can be suppressed.

[Brief description of the drawings]

FIG. 1 is a partial sectional view showing a first embodiment according to the present invention.

FIG. 2 is a schematic sectional view of the same embodiment.

FIG. 3 is a partial sectional view showing a second embodiment according to the present invention.

FIG. 4 is a partial sectional view showing a third embodiment according to the present invention.

FIG. 5 is a partial sectional view showing a fourth embodiment according to the present invention.

FIG. 6 is a schematic sectional view of a fifth embodiment according to the present invention.

FIG. 7 is a partial cross-sectional view in the same embodiment.

FIG. 8 is a partial sectional view showing a conventional hydraulic switching device for a friction wheel type continuously variable transmission.

FIG. 9 is a schematic sectional view of the same example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cylinder body 1a, 1b Cylinder body member 2 Counter shaft 3 Arm member 3p Projection part (idling side) 3po Projection part (lock side) 4 Spool 5 Valve body 5a Upper body 5b Lower body 6 Transmission case 6w Partition wall (gear housing) 7 Spring 8 Oil pan 10 Servo piston 11 Tension spring 12 Compression spring B Hydraulic switching valve for forward / backward movement Co One-way clutch S Stopper S1, S3 Stopper (idle side) S2 Stopper (lock side)

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) F16H 15 / 38,61 / 00

Claims (7)

(57) [Claims] 1. A forward / backward hydraulic pressure switch for switching a supply pressure to a servo piston in accordance with a forward / backward movement of a vehicle by pressing a spool, the cylinder body being a servo piston which controls a shift of a friction wheel type continuously variable transmission. The valve body of the valve,
An arm member rotatably fitted via a one-way clutch to a counter shaft between the cylinder body of the servo piston and the valve body of the forward-backward hydraulic switching valve, the one-way clutch locking the arm member When the one-way clutch idles on the counter shaft, the arm member is pressed against the spool of the forward / reverse hydraulic switching valve. In a hydraulic pressure switching device for a friction wheel type continuously variable transmission that switches a supply pressure to the piston by releasing a pressure on a spool, a stopper that restricts idle rotation of the arm member on a cylinder body of the servo piston. A hydraulic switching device for a friction wheel type continuously variable transmission, comprising: 2. A hydraulic switching device for a friction wheel type continuously variable transmission according to claim 1, wherein said arm member is provided with an elastic member for elastically supporting said arm member at a rotation limit position on the idling side. 3. The hydraulic switching device for a friction wheel type continuously variable transmission according to claim 2, wherein the elastic member is a tension element. 4. The hydraulic switching device for a friction wheel type continuously variable transmission according to claim 2, wherein the elastic member is a pressing element. 5. The hydraulic switching of a friction wheel type continuously variable transmission according to claim 1, wherein a stopper for restricting rotation of the arm member on the lock side is provided on a cylinder body of the servo piston. apparatus. 6. A forward / backward hydraulic pressure switch for switching a supply pressure to the servo piston in response to a forward / backward movement of the vehicle by pressing a spool, the cylinder body being a servo piston for controlling a shift of a friction wheel type continuously variable transmission. The valve body of the valve,
An arm member rotatably fitted via a one-way clutch to a counter shaft between the cylinder body of the servo piston and the valve body of the hydraulic switching valve for forward / reverse movement, and the one-way clutch locks the arm member When the one-way clutch idles on the counter shaft, the arm member is pressed against the spool of the forward / reverse hydraulic switching valve. A hydraulic switching device for a friction wheel type continuously variable transmission that switches the supply pressure to the piston by releasing the pressure on the piston, wherein a transmission accommodating a cylinder body of the servo piston and a valve body of the hydraulic switching valve for forward and backward movement. A stopper is provided on a partition wall of the case to restrict rotation on the idling side of the arm member. Hydraulic switching device that friction wheel continuously variable transmission. 7. The continuously variable transmission according to claim 6, wherein the partition wall of the transmission case is a gear housing that houses an output gear that transmits power from an output disk to a counter shaft. Hydraulic switching device.