Control valve

Abstract

To provide a control valve preventing slipping of a clutch due to oil leakage.SOLUTION: A control valve 100 is equipped with a first rack 10, a second rack 20, a pinion gear 30 disposed so as to move in a longitudinal direction around a neutral position, and a valve body 40. The valve body is configured to be in a blocking state when the pinion gear is at the neutral position, and to be in a communication state when the pinion gear moves from the neutral position in a longitudinal direction. The valve body is configured to communicate an air chamber C with the outside so as to operate a release piston 210 in the communication state, and to block the air chamber so as to stop the release piston in the blocked state. The first rack is configured to move a predetermined amount with a clutch operation to move the pinion gear from the neutral position in a longitudinal direction. The second rack is configured to move a predetermined amount in the opposite direction to the first rack, with the movement of the release piston.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a control valve.

Background Art

[0002] In a clutch device for a vehicle, a clutch release device is provided to perform an operation for releasing the power transmission state (hereinafter referred to as a release operation). The release device operates a slave cylinder by operating a clutch pedal, for example, and thereby a release bearing moves in the axial direction. By this movement of the release bearing, the central portion of the diaphragm spring constituting the clutch device is pressed, and the pressing force of the pressure plate against the clutch disc is released. That is, the power transmission state in the clutch device is released.

[0003] Further, in order to reduce the stepping force during the release operation without increasing the size of the clutch release device, a Concentric Slave Cylinder (CSC) type release device is used. The CSC type release device has a release cylinder and a release piston provided coaxially with the input shaft of the transmission. Then, by supplying hydraulic pressure or pneumatic pressure to the release cylinder to operate the release piston, the release bearing moves in the axial direction. Hereinafter, a CSC type release device operated by pneumatic pressure is referred to as a pneumatic CSC.

[0004] A clutch device having a pneumatic CSC includes a control valve that controls a release bearing device. The control valve is connected to an air source and controls the position of the clutch release device by adjusting the amount of air supplied to the clutch release device according to the depression amount of the clutch pedal.

[0005] Japanese Patent Application Laid-Open No. 10-47381 ( Patent Document 1) discloses a control valve using a hydraulic valve cylinder in a pneumatic CSC.

Prior Art Documents

Patent Document

[0006]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0007] When controlling a clutch release device with a control valve using a hydraulic valve cylinder, oil leakage from the hydraulic cylinder may occur, and the clutch may slip.

[0008] An object of the present invention is to provide a control valve that prevents clutch slip due to oil leakage.

Means for Solving the Problems

[0009] (1) A control valve according to one aspect of the present invention is a control valve for controlling a clutch release device having a release piston, a cylinder, and an air chamber. The control valve includes a first rack, a second rack, a pinion gear, and a valve body. The first rack is arranged to be movable in the longitudinal direction. The second rack is arranged to be movable in the longitudinal direction. The pinion gear is arranged between the first rack and the second rack. The pinion gear meshes with the first rack and the second rack. The pinion gear is arranged to be movable in the longitudinal direction about a neutral position. The valve body is configured to be in a closed state when the pinion gear is in the neutral position, and to be in a communicating state when the pinion gear moves in the longitudinal direction from the neutral position. The valve body is configured to communicate the air chamber with the outside to operate the release piston in the communicating state, and to close the air chamber to stop the release piston in the closed state. The first rack is configured to move by a predetermined displacement amount by a clutch operation to move the pinion gear in the longitudinal direction from the neutral position. The second rack is configured to move by a predetermined displacement amount in a direction opposite to the first rack as the release piston moves.

[0010] In the control valve configured as described above, by the clutch operation, the first rack moves by a predetermined displacement amount. Since the pinion gear meshes with the first rack, the pinion gear also moves longitudinally from the neutral position. As a result, the valve body also changes from the closed state to the communicating state. Thereby, the air chamber communicates with the outside, and the release piston moves. As the release piston moves, the second rack moves by the predetermined displacement amount in the direction opposite to the first rack. Since the pinion gear meshes with the second rack, the pinion gear also moves longitudinally and returns to the neutral position. As a result, the valve body also changes from the communicating state to the closed state, and the movement of the release piston stops.

[0011] By the above operation, the control valve can control the position of the release piston with respect to the clutch operation to control the clutch release device. Further, since the control valve configured as described above does not use a hydraulic valve cylinder, it is possible to prevent clutch slip due to oil leakage from the hydraulic cylinder.

[0012] (2) Preferably, the communicating state includes a first communicating state in which the air chamber communicates with the air source. When the pinion gear moves to a first position on the first side in the longitudinal direction from the neutral position, the valve body becomes the first communicating state. The first rack moves the pinion gear from the neutral position to the first position when the clutch operation is in the on state.

[0013] (3) Preferably, the communicating state includes a second communicating state in which the air chamber communicates with the atmospheric pressure portion. When the pinion gear moves to a second position on the second side in the longitudinal direction from the neutral position, the valve body becomes the second communicating state. The first rack moves the pinion gear from the neutral position to the second position when the clutch operation is in the off state.

[0014] (4) Preferably, the control valve further includes a valve piston. The valve piston is arranged to be movable longitudinally together with the pinion gear. The valve piston presses the valve body to switch the valve body between the communicating state and the closed state.

[0015] (5) Preferably, the valve body has a first sleeve and a second sleeve. The first sleeve opens when the pinion gear moves from the neutral position to a first position on the first longitudinal side. The second sleeve opens when the pinion gear moves from the neutral position to a second position on the second longitudinal side.

[0016] (6) Preferably, the valve body includes a silencer structure. The silencer structure suppresses the sound when air is discharged. [Advantages of the Invention]

[0017] In the present invention as described above, it is possible to provide a control valve that prevents slippage of the clutch due to oil leakage. [Brief Description of the Drawings]

[0018]

Figure 1

Figure 2

[0019] [Overall Configuration] FIG. 1 is a cross-sectional view of a control valve 100 and a clutch release device 200 according to an embodiment of the present invention. The control valve 100 is used for the clutch release device 200. The clutch device is a device for transmitting and interrupting torque from a flywheel (not shown) on the engine side to a transmission input shaft (not shown). The control valve 100 and the clutch release device 200 are connected via an air pipe (not shown). A clutch device is disposed above the clutch release device 200. A transmission (not shown) is disposed below the clutch release device 200.

[0020] In the cross-sectional view of FIG. 1, the line O-O is the rotation axis. In the following description, the "longitudinal direction" refers to the direction in which the first rack 10 described later extends. The lower side of FIG. 1 is defined as the "first longitudinal side", and the upper side of FIG. 1 is defined as the "second longitudinal side". The "axial direction" refers to the direction in which the rotation axis O extends. The "radial direction" means the radial direction of a circle centered on the rotation axis O.

[0021] [Clutch release device 200] The clutch release device 200 is a device for performing a release operation on a clutch device disposed between an engine and a transmission. That is, by this clutch release device 200, the power transmission state in the clutch device is released.

[0022] The clutch release device 200 includes a cylinder 220, a release piston 210, and an air chamber C.

[0023] [Cylinder 220] The cylinder 220 has an inner peripheral cylindrical portion 221, an outer peripheral cylindrical portion 222, and a bottom portion 223.

[0024] The inner peripheral cylindrical portion 221 is disposed coaxially with the input shaft (not shown) of the transmission on the outer side in the radial direction. The outer peripheral cylindrical portion 222 extends from the outer periphery of the bottom portion 223 to the second axial side. The outer peripheral cylindrical portion 222 extends substantially parallel to the inner peripheral cylindrical portion 221. An air supply port 224 for supplying air to the air chamber C is formed in the bottom portion 223.

[0025] [Release piston 210] The release piston 210 is disposed coaxially with the input shaft between the inner peripheral cylindrical portion 221 and the outer peripheral cylindrical portion 222 of the cylinder 220. The release piston 210 is movable axially along the inner peripheral cylindrical portion 221 and the outer peripheral cylindrical portion 222 of the cylinder 220.

[0026] A release bearing 211 is fitted onto the end of the release piston 210 on the second axial side. A cylindrical release member 230 is mounted on the release bearing 211. The release member 230 is in contact with the inner peripheral end of the diaphragm spring 300 of the clutch device.

[0027] The release piston 210 is arranged to be longitudinally movable between a non-operating position and an operating position. The operating position is the final position when air enters the air chamber C and the release piston 210 has finished moving. That is, the operating position is the position of the release piston 210 when the clutch device is in the clutch-off state. The non-operating position is the final position when air is discharged from the air chamber C and the release piston 210 has finished moving. That is, the non-operating position is the position of the release piston 210 when the clutch device is in the clutch-on state. The non-operating position is on the first axial side of the release axis direction relative to the operating position.

[0028] <Air chamber C> The air chamber C is defined by the cylinder 220 and the release piston 210. Specifically, the air chamber C is formed by the inner peripheral cylindrical portion 221, the bottom portion 223, the outer peripheral cylindrical portion 222 of the cylinder 220, and the release piston 210.

[0029] A spring 301 for biasing the release piston 210 toward the second axial side is provided in the air chamber C. By the spring 301, the release member 230 is pressed against the inner peripheral end of the diaphragm spring 300 with a predetermined pressure. A preload acts between the release member 230 and the diaphragm spring 300 when no air is supplied to the air chamber C.

[0030] [Control valve 100] The control valve 100 is attached to the clutch release device 200. The control valve 100 is arranged such that the axial direction of the clutch release device 200 and the axial direction of the control valve 100 are parallel. The control valve 100 controls the clutch release device 200.

[0031] The control valve 100 includes a first rack 10, a second rack 20, a pinion gear 30, a valve piston 42, and a valve body 40.

[0032] <The first rack 10> The first rack 10 is in the shape of an elongated plate. The first rack 10 is connected to the clutch pedal. The first rack 10 is arranged such that its longitudinal direction is parallel to the axial direction of the clutch release device 200 and is movable in the longitudinal direction. In this embodiment, when the clutch pedal is depressed, the first rack 10 moves to the first side in the longitudinal direction, and when the depression of the clutch pedal is released, the first rack 10 is configured to move to the second side in the longitudinal direction.

[0033] The first rack 10 has a plurality of grooves 11 arranged in the longitudinal direction on the surface facing the second rack 20.

[0034] <The second rack 20> The second rack 20 is in the shape of an elongated plate. The second rack 20 is attached to a member that moves together with the release piston 210. The second rack 20 may be directly attached to the release piston 210 of the clutch release device 200. The second rack 20 is arranged such that its longitudinal direction is parallel to the axial direction of the clutch release device 200 and is movable in the longitudinal direction. That is, the second rack 20 is arranged parallel to the first rack 10.

[0035] The second rack 20 has a plurality of grooves 21 arranged in the longitudinal direction on the surface facing the first rack 10.

[0036] <The pinion gear 30> The pinion gear 30 is disposed between the first rack 10 and the second rack 20. The pinion gear 30 meshes with the first rack 10 and the second rack 20. More specifically, the pinion gear 30 has a disk-shaped main body 31 and a plurality of teeth 32 on the outer peripheral portion of the main body 31. The plurality of teeth 32 mesh with the plurality of grooves 11 of the first rack 10 and the plurality of grooves 21 of the second rack 20.

[0037] The pinion gear 30 is disposed so as to be movable in the longitudinal direction about a neutral position. More specifically, the pinion gear 30 is disposed so as to be movable in the longitudinal direction between a first position on the first side in the longitudinal direction and a second position on the second side in the longitudinal direction about the neutral position.

[0038] The pinion gear 30 is rotatable. When the first rack 10 moves in the longitudinal direction due to the rotation of the pinion gear 30, the second rack 20 can move in a direction opposite to that of the first rack 10.

[0039] <Valve piston 42> The valve piston 42 is cylindrical. The valve piston 42 is movable in the release axial direction. The valve piston 42 is disposed so as to be movable in the longitudinal direction within the valve cylinder 41. The valve piston 42 is disposed coaxially with the valve cylinder 41. The valve piston 42 is operated by the pinion gear 30.

[0040] The end portion on the second side in the longitudinal direction of the valve piston 42 is connected to the pinion gear 30. Thereby, the valve piston 42 moves axially in conjunction with the pinion gear 30. The valve piston 42 rotatably supports the pinion gear 30.

[0041] <Valve body 40> The valve body 40 is fixed to the cylinder 220 of the clutch release device 200. More specifically, the valve body 40 is fixed to the outer peripheral cylindrical portion 222 of the cylinder 220. An air source (not shown) is connected to the valve body 40.

[0042] The valve body 40 can be switched between a closed state and a communication state. The communication state includes a first communication state and a second communication state. That is, in the present embodiment, the valve body 40 can be switched to any one of a closed state, a first communication state, and a second communication state. When the pinion gear 30 is in the neutral position, the valve body 40 is in the closed state. In the closed state, the valve body 40 closes the air chamber C so as to stop the release piston 210.

[0043] When the pinion gear 30 moves in the longitudinal direction from the neutral position, the valve body 40 is in the communication state. In the communication state, the valve body 40 communicates the air chamber C with the outside so as to operate the release piston 210. The outside is an air source and an atmospheric pressure part. The atmospheric pressure part is a part that communicates with the atmosphere. The communication state includes a first communication state and a second communication state. In the first communication state, the valve body 40 communicates the air chamber C with the air source. In the second communication state, the valve body 40 communicates the air chamber C with the atmospheric pressure part. Here, the air source and the atmospheric pressure part correspond to the above-mentioned outside. The atmospheric pressure part is a part that communicates with the atmosphere.

[0044] The valve body 40 is connected to the air supply port 224 of the clutch release device 200 via an air pipe. Thereby, in the first communication state, the valve body 40 can send air to the air chamber C of the clutch release device 200. The valve body 40 also communicates with an atmospheric pressure part (not shown). Thereby, in the second communication state, the valve body 40 can exhaust the air in the air chamber C.

[0045] The valve body 40 includes a valve cylinder 41, a first sleeve 43, a second sleeve 44, and a silencer structure 45. The first sleeve 43 and the second sleeve 44 are arranged to be movable in the longitudinal direction within the valve cylinder 41.

[0046] The valve cylinder 41 is cylindrical. The valve cylinder 41 is arranged coaxially with the valve piston 42. The valve cylinder 41 has an air supply port 41a for supplying air to the clutch release device 200.

[0047] The valve cylinder 41 further has a protrusion 41b between the first sleeve 43 and the second sleeve 44. The protrusion 41b abuts against the end of the first sleeve 43 on the second side in the longitudinal direction when the valve body 40 is in the closed state, blocking the air communication.

[0048] The first sleeve 43 is hollow and cylindrical. When the valve body 40 is in the closed state, the first sleeve 43 is biased toward the second side in the longitudinal direction by the first valve spring 43a. The end of the first sleeve 43 on the second side in the longitudinal direction abuts against the end of the second sleeve 44 on the first side in the longitudinal direction and the protrusion 41b of the valve cylinder 41.

[0049] When the valve body 40 is in the first communication state, the protrusion 41b is separated from the end of the first sleeve 43 on the second side in the release axial direction. This state is the state where the air supply circuit is open, and air is supplied to the air chamber C of the clutch release device 200.

[0050] The first sleeve 43 is connected to the silencer structure 45 at the end on the first side in the longitudinal direction. The silencer structure 45 provides a space. The silencer structure 45 also functions as an exhaust port. The silencer structure 45 suppresses the sound when air is discharged.

[0051] The second sleeve 44 is cylindrical. The second sleeve 44 has a recess extending in the longitudinal direction at the central portion. The valve piston 42 is inserted into this recess. Therefore, when the valve piston 42 moves to the first side in the longitudinal direction, Second sleeve 44 it can move together with the valve piston 42.

[0052] When the valve body 40 is in the closed state, the second sleeve 44 is biased toward the second side in the longitudinal direction by the second valve spring 44a. The end of the second sleeve 44 on the first side in the longitudinal direction abuts against the end of the first sleeve 43 on the second side in the longitudinal direction.

[0053] When the valve body 40 is in the second communication state, a gap is formed between the end of the first sleeve 43 on the second side in the release axial direction and the end of the second sleeve 44 on the first side in the release axial direction. This state is the state where the exhaust circuit is open. At this time, the air of the clutch release device 200 is exhausted through the hollow portion of the first sleeve 43.

[0054] [Operation] The clutch device takes a clutch-on state and a clutch-off state. When the clutch device is in the clutch-on state, the clutch disc is clamped between the pressure plate and the flywheel by the pressing force of the diaphragm spring 300. Therefore, the power from the engine is transmitted to the transmission. On the other hand, when the clutch device is in the clutch-off state, the clutch disc separates from the flywheel. Therefore, the transmission of power from the engine to the transmission is cut off.

[0055] The clutch operation includes a clutch-on operation for putting the clutch device in the clutch-on state and a clutch-off operation for putting the clutch device in the clutch-off state. Note that the clutch-off operation is an operation of stepping on the clutch pedal, and the clutch-on operation is an operation of releasing the clutch pedal. That is, the clutch device is normally in the clutch-on state.

[0056] Hereinafter, the operation will be described with reference to FIG. 2.

[0057] When the clutch device is in the clutch-on state, the clutch release device 200 is biased against the diaphragm spring 300 by the biasing force of only the spring 301. At this time, as shown in FIG. 2(1), the pinion gear 30 is in the neutral position.

[0058] When the clutch-off operation is performed, the first rack 10 moves a predetermined displacement amount to the first side in the longitudinal direction. At this time, since the second rack 20 has not moved yet and the pinion gear 30 is engaged with the first rack 10, the pinion gear 30 moves from the neutral position to the first side in the longitudinal direction. The final position where the pinion gear 30 has finished moving due to this clutch-off operation is defined as the first position.

[0059] As a result, the pinion gear 30 moves the valve piston 42 to the first side in the longitudinal direction. Therefore, the second sleeve 44 moves integrally with the valve piston 42 and presses the end portion on the second side in the longitudinal direction of the first sleeve 43. Thereby, the first sleeve 43 moves to the first side in the longitudinal direction and opens, and as shown in (2) of FIG. 2, the valve body 40 is in the first communication state. In the first communication state, the valve body 40 communicates the air chamber C with the air source. When communicated with the air source, air is supplied to the air chamber C. When air is supplied to the air chamber C, the release piston 210 moves from the non-operating position to the second side in the longitudinal direction and takes the operating position. As a result, the release member 230 presses the central portion of the diaphragm spring 300, releasing the pressing force of the pressure plate. As a result, the clutch disc separates from the flywheel, and the power transmission from the engine to the transmission is interrupted.

[0060] Also, as the release piston 210 moves from the first position of release to the operating position, the second rack 20 moves to the second side in the longitudinal direction by the same displacement amount as the displacement amount by which the first rack 10 has moved. At this time, the first rack 10 does not move. Since the pinion gear 30 is engaged with the second rack 20, as shown in (3) of FIG. 2, the pinion gear 30 also moves to the second side in the longitudinal direction and returns to the neutral position. Thereby, the valve body 40 also changes from the first communication state to the closed state, and the movement of the release piston 210 stops.

[0061] On one hand, when the clutch on is operated, the first rack 10 moves a predetermined displacement amount toward the second side in the longitudinal direction. At this time, since the second rack 20 has not moved yet and the pinion gear 30 is engaged with the first rack 10, the pinion gear 30 moves toward the second side in the longitudinal direction from the neutral position. Let the final position where the pinion gear 30 has finished moving due to this clutch on operation be the second position.

[0062] As a result, the pinion gear 30 moves the valve piston 42 toward the second side in the longitudinal direction. Therefore, the second sleeve 44 opens, and as shown in Fig. 2(4), the valve body 40 enters the second communication state. In the second communication state, the valve body 40 communicates the air chamber C with the atmospheric pressure portion. By communicating with the atmospheric pressure portion, air is exhausted from the air chamber C. When the air pressure in the air chamber C decreases, the release piston 210 moves from the operating position toward the first side in the longitudinal direction by the pressing force of the diaphragm spring 300 and takes the non-operating position. Thereby, the clutch disc presses the flywheel, and the power from the engine is transmitted to the transmission.

[0063] As the release piston 210 moves from the operating position to the non-operating position, the second rack 20 moves toward the first side in the longitudinal direction by the same displacement amount as the displacement amount by which the first rack 10 has moved. At this time, the first rack 10 does not move. Since the pinion gear 30 is engaged with the second rack 20, as shown in Fig. 2(1), the pinion gear 30 also moves toward the first side in the longitudinal direction and returns to the neutral position. Thereby, the valve body 40 also changes from the second communication state to the closed state, and the movement of the release piston 210 stops.

[0064] By the above operations, the control valve 100 can control the position of the release piston 210 of the clutch release device 200 with respect to the clutch operation, and thus control the clutch release device 200. Further, since the control valve 100 according to one aspect of the present invention does not use a hydraulic cylinder, it is possible to prevent clutch slip due to oil leakage from the hydraulic cylinder.

[0065] [Other Embodiments] The present invention is not limited to the above-described embodiments, and various modifications or corrections can be made without departing from the scope of the present invention.

[0066] Modification example 1 In the above embodiment, in both the clutch-off operation and the clutch-on operation, when the first rack 10 moves in the longitudinal direction via the pinion gear 30, the second rack 20 moves in the direction opposite to the first rack 10 by the same displacement amount as the displacement amount of the first rack 10. However, it is not particularly limited thereto. Only in the clutch-off operation, the first rack 10 and the second rack 20 may move. Also, only in the clutch-on operation, the first rack 10 and the second rack 20 may move.

[0067] Modification example 2 In the above embodiment, the control valve 100 controlled the position of the release piston 210 in response to the clutch operation by the clutch pedal. However, it is not particularly limited thereto. The control valve 100 may control the position of the clutch release device 200 in response to the clutch operation by other means.

[0068] Modification example 3 In the above embodiment, the second rack 20 is fixed to the release piston 210. However, it is not particularly limited thereto. For example, the second rack 20 may be fixed to another part of the release piston 210.

[0069] Modification example 4 In the above embodiment, the valve body 40 includes the first sleeve 43 and the second sleeve 44. However, it is not particularly limited thereto. For example, the valve body 40 may have only one valve.

[0070] Modification example 5 The shape and configuration of the clutch release device 200 are not limited to the above embodiment, and various modifications are possible.

Explanation of Reference Numerals

[0071] 10 First Rack 20 Second Rack 30 Pinion Gear 40 Valve Body 42 Valve Piston 43 First Sleeve 44 Second Sleeve 100 Control Valve 200 Clutch Release Device 210 Release Piston C Air Chamber

Claims

1. A control valve for controlling a clutch release device having a release piston, a cylinder, and an air chamber, comprising: a first rack extending in a longitudinal direction and arranged to be movable in the longitudinal direction; a second rack extending in the longitudinal direction and arranged to be movable in the longitudinal direction; a pinion gear disposed between the first rack and the second rack, meshing with the first rack and the second rack, and arranged to be movable in the longitudinal direction about a neutral position; a valve body configured to be in a closed state when the pinion gear is at the neutral position and in a communicating state when the pinion gear moves in the longitudinal direction from the neutral position; wherein the valve body is configured to communicate the air chamber with the outside to operate the release piston in the communicating state, and to close the air chamber to stop the release piston in the closed state; the first rack is configured to move by a predetermined displacement amount by a clutch operation to move the pinion gear in the longitudinal direction from the neutral position; the second rack is configured to move the predetermined displacement amount in a direction opposite to the first rack as the release piston moves; a control valve.

2. The communicating state includes a first communicating state in which the air chamber communicates with an air source, the valve body enters the first communicating state when the pinion gear moves to a first position on a first longitudinal side which is one side of the longitudinal direction from the neutral position, the first rack moves the pinion gear from the neutral position to the first position when the clutch operation is in an on state; The control valve according to claim 1.

3. The communicating state includes a second communicating state in which the air chamber communicates with an atmospheric pressure portion, the valve body enters the second communicating state when the pinion gear moves to a second position on a second longitudinal side which is the other side of the longitudinal direction from the neutral position, the first rack moves the pinion gear from the neutral position to the second position when the clutch operation is in an off state; The control valve according to claim 2.

4. further comprising a valve piston arranged to be movable in the longitudinal direction together with the pinion gear and pressing the valve body to switch the valve body between the communicating state and the closed state. The control valve according to any one of claims 1 to 3.

5. The valve body has a first sleeve and a second sleeve. The first sleeve opens when the pinion gear moves to a first position on a first side in the longitudinal direction, which is one side of the longitudinal direction from the neutral position. The second sleeve opens when the pinion gear moves to a second position on a second side in the longitudinal direction, which is the other side of the longitudinal direction from the neutral position. The control valve according to any one of claims 1 to 4.

6. The valve body includes a silencer structure that suppresses the sound when air is discharged. The control valve according to any one of claims 1 to 5.

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