JP2956190B2 - Clutch shock torque prevention valve - Google Patents

Description

The present invention relates to a clutch anti-shock torque valve.

(B) Conventional technology In a manually operated vehicle, when shifting gears, the clutch pedal is depressed to temporarily disconnect the connection between the engine and the transmission, and the shift lever is operated to change the gear ratio of the gear. Thereafter, a series of shift operations of releasing the depression of the clutch pedal and restoring the connection between the engine and the transmission are performed.
If the clutch is not properly returned among these operations, the so-called clutch shock torque causes the engine to stop, the vehicle to be shocked, or the clutch to wear abnormally. Tokiko 46-6242
Japanese Patent Application Laid-Open Publication No. H11-163873 discloses that after depressing a clutch pedal to apply hydraulic pressure from the master cylinder to the operating cylinder to disengage the clutch, switch the transmission gear, and then move the operating cylinder at an appropriate speed when the clutch pedal is released. A throttle valve mechanism is shown. As a result, the throttle effect can be obtained only when the hydraulic fluid flows from the operating cylinder side to the master cylinder side, the shock torque of the clutch can be prevented, and the clutch can be connected smoothly.

In order to achieve a similar object, a needle valve having a cylindrical cylinder body, a valve body having one end fixed to the other end thereof, and a cross-sectional area of a shaft gradually changing at the other end side, is provided. There is a throttle mechanism in which an inner diameter portion is slidably fitted to a diameter portion and an outer diameter portion is slidably fitted to a cylinder body, and a piston forms a liquid passage together with a needle valve. In this throttle mechanism, the cross-sectional area of the throttle changes as the piston moves with respect to the needle valve.
In this case, the same effect as above can be obtained.

(C) Problems to be Solved by the Invention However, according to the above-described conventional shock torque prevention mechanism of the clutch, the minimum throttle area of the liquid passage is:
It depends on the processing dimensions of each part when the cylinder body, needle valve and piston are combined. In other words, the position where the restriction of the liquid passage is minimized is a position where one end of the piston is in contact with the end face of the hole of the cylinder body, and the minimum area of the restriction is determined by the related dimension of the needle valve and the piston at this time. Therefore, the minimum area of the throttle cannot be determined only from the related dimensions of the needle valve and the piston, and the depth of the hole of the cylinder body that accommodates them is related. For this reason, even if these components are manufactured under certain quality control conditions, there is a problem in that when these components are randomly combined, the function of preventing the shock torque of the clutch varies. An object of the present invention is to solve such a problem.

(D) Means for Solving the Problems According to the present invention, the position where the liquid passage is most narrowed is determined only by the length dimension of the relevant portion of the needle valve and the piston, and the length direction of the cylinder body accommodating these components is determined. The above-mentioned problem is solved by making it not related to the size of. That is, the present invention provides a clutch pedal (2).
The anti-shock torque valves (6, 6 ', 6 ") arranged in the hydraulic circuit between the master cylinder (4) operated by the actuator and the operating cylinder (8) for operating the withdrawal lever (10) There is a cylindrical chamber inside (12
b) having a cylinder body (12) and a cylindrical chamber (12
b) It is fixed to the cylinder body (12) and the piston (16) which is slidably fitted inside and separates it into two liquid chambers of the first liquid chamber (6a) and the second liquid chamber (6b). And a spring (18) for pushing the piston (16) toward the second liquid chamber (6b). The first liquid chamber (6a) is connected to the master cylinder (4). The second liquid chamber (6b) is connected to the operating cylinder (8),
The piston (16) is provided with a through hole (16a) for communicating the two liquid chambers (6a, 6b) with each other.
4) extends into the through hole (16a), and the piston (16) pushes the liquid passage formed between the through hole (16a) and the needle valve (14) to the stop position by the spring (18). The piston (16) is the first liquid chamber (6a)
The needle valve (14) has a stopper (14c) at a position facing the end of the piston (16), and the needle valve (1)
A part of 4) was cut out, and a flow path connecting the master cylinder (4) and the first liquid chamber (6a) was formed between the cylinder body (11) and the cylinder body (11).

Incidentally, both or one of the piston (16) and the needle valve (14) may be made of plastic.

Further, when the piston (16) is made of metal, a buffer member (22a or 22b) made of a soft material such as rubber is provided in the second liquid chamber (6a) at a position facing the piston (16). You may do so. In addition, the code | symbol in a parenthesis shows the corresponding member of an Example.

(E) Operation When the clutch pedal (2) is depressed from the state in which the clutch is disengaged by depressing the clutch pedal (2), the hydraulic fluid from the operating cylinder (8) receives the shock torque prevention valves (6, 6 '). , 6 ") and returns to the master cylinder (4). The flow rate of this hydraulic fluid is formed by the through hole (16a) at the center of the piston (16) and the valve body of the needle valve (14). It is determined by the area of the restrictor in the liquid passage, the pressure difference acting before and after the restrictor, etc. The liquid passage is most restricted when the end of the piston (16) contacts the stopper of the needle valve (14). The minimum throttle area is regulated by the relation between the needle valve (14) and the piston (16).
Does not matter. With this configuration, it is possible to reduce the variation in the shock torque prevention function of the shock torque prevention valves (6, 6 ', 6 ").

(F) Embodiment FIG. 1 shows an embodiment of the present invention. The operation of the clutch pedal 2 is transmitted to the master cylinder 4 connected thereto, and the hydraulic fluid sent out therefrom flows into the operating cylinder 8 through the shock torque prevention valve 6. One end of a withdrawal lever 10 is connected to the operating cylinder 8.
The other end of 10 is connected to a clutch (not shown).
Cylinder body 12 constituting shock torque prevention valve 6
Is formed in a cylindrical shape having a small-diameter hole 12a and a larger-diameter hole 12b, and a connection port 12c communicating with the small-diameter hole 12a is provided at one end. The needle valve 14 has a valve body 14a at one end, and a collar-shaped stopper 1 at an intermediate portion.
4c, and a fixed portion on the other end side is fixed to a small-diameter hole 12a of the cylinder body 12. The valve body portion 14a has a shape in which a part of the shaft is cut off so as to be larger at the tip obliquely in the axial direction, and the other end of the needle valve 14 and the outer diameter of the stopper 14c are partially notched in the axial direction. Thus, a flow path 14b is formed. The stopper 14c of the needle valve 14 is
The second hole 12b is fitted. Further, the outer diameter portion of a piston 16 formed in a double cylindrical shape is slidably fitted in the hole 12b of the cylinder body 12. The through hole 16a inside the piston 16 is slidably fitted in the valve body 14a of the needle valve 14. The piston 16 is formed of a plastic material such as engineering plastic. As the piston 16 moves with respect to the needle valve 14, the throttle area of the liquid passage formed by the valve body 14c of the needle valve 14 and the through hole 16a of the piston 16 changes. Stopper part 14c of needle valve 14
Functions as a stopper member that regulates the rightward stroke of the piston 16 in the figure. That is, the stopper
The minimum throttle area of the liquid passage is determined in a state where the left end of the piston 16 in the figure contacts the piston 14c. The recess provided in the stopper portion 14c of the needle valve 14 and the piston 16
A spring 18 is arranged between the spring 18 and the cylindrical hole. The spring 18 pushes the piston 16 in the direction to increase the throttle area in the right direction in FIG. The space in which the spring 18 is arranged is formed in the first liquid chamber 6a. Cylinder body 12
A female screw is provided on the right end side in the figure
A joint 20 having 20a is screwed. In FIG.
The left end of the joint 20 also serves as a positioning member for setting the stop position of the piston 16 in the right direction in the drawing. Also fittings
Operating cylinder 8 between 20 and piston 16
The second liquid chamber 6b is formed so that the hydraulic fluid flowing from the piston 16 presses the right end of the piston 16 in the drawing. A seal member 24 is provided between the inner diameter portion of the cylinder body 12 and the outer diameter portion of the screw of the joint 20, and the cylinder body 12 is fixed to a vehicle body (not shown) by a bracket 26. It has become. In this assembled state, a gap H is formed between the right end of the stopper portion 14c of the needle valve 14 and the left end of the piston 16 in the drawing. When the piston 16 is pushed to the left in the figure and the clearance H is 0, the minimum throttle area of the liquid passage already described is the needle valve
It is determined by the relative size of the piston 14 and the piston 16, and is not related to the depth of the hole 12b of the cylinder body 12. That is,
With this configuration, the minimum throttle area of the liquid passage can be determined only by the relational size of the needle valve 14 and the piston 16.

Next, the operation of this embodiment will be described. When the clutch pedal 2 is depressed for shifting, the piston of the master cylinder 4 is pushed and the hydraulic fluid is discharged. The discharged hydraulic fluid flows into the first liquid chamber 6a from the connection port 12c of the anti-shock torque valve 6 via the flow path 14b, and pushes the piston 16 rightward in the drawing, and the valve body 14a of the needle valve 14 and the piston 16 The throttle of the liquid passage formed by the through hole 16a is opened, and the second
It flows into the operating cylinder 8 from the connection port 20 via 6b. With this liquid pressure, the piston of the operating cylinder 8 is pushed rightward in the drawing, and the withdrawal lever
10 is pushed rightward in the figure. As a result, the clutch (not shown) is disengaged, and the shift gear is switched by operating the shift lever (not shown). After the switching is completed, when the depression of the clutch pedal is released, the withdrawal lever 10 is pushed leftward in the drawing by the return spring of the clutch (not shown), and the piston of the operating cylinder 8 is pushed in the same direction. Further, the piston of the master cylinder 4 is also about to be returned to the initial position by a return spring (not shown). At this time, if the release of the clutch pedal 2 is abrupt, the pressure in the first liquid chamber 6a of the cylinder body 12 becomes negative, so that
The piston 16 is pushed to the left in the figure against the force of the spring 18 due to the pressure difference between the piston 16 and the second liquid chamber 6b, thereby reducing the restriction of the liquid passage. This allows the working fluid to flow while the flow rate is adjusted.
After passing through 14d, it returns to the master cylinder 4. By doing so, the movements of the piston of the operating cylinder 8 and the withdrawal lever 10 become gentle, and the generation of the shock torque of the clutch can be prevented, so that the clutch can be connected smoothly. The minimum throttle area of the liquid passage is obtained when the clearance H is zero, but is determined only by the relational dimension between the needle valve 14 and the piston 16 having the minimum throttle area, and is not affected by the dimensions of the cylinder body. Therefore, by controlling the dimensions of the needle valve 14 and the piston 16, the magnitude of the shock torque of the clutch can be reduced within a predetermined range. Even if the piston 16 moves to the left in the figure and collides with the stopper 14c, the piston 16 is made of plastic, so that noise due to the collision hardly occurs. The same applies to the case where the right end of the piston 16 in the figure collides with the left end of the joint 20.

In the above description, the piston 16 is made of plastic, but the piston 16 may be made of metal and both or one of the joint 20 and the needle valve 14 may be made of plastic.

The needle valve 14 is made of plastic, and the piston
16 and the joint 20 are made of metal, and the piston 16 is
The shock torque preventing valve 6 'or 6 "having a structure as shown in FIG.
It can also be. In these embodiments, the metal coupling 20 incorporates a cushioning member 22a or 22b made of a soft material such as plastic or rubber, which is generated when the metal piston 16 collides with these members. Noise can be reduced.

(G) Effects of the present invention As described above, according to the present invention, among the components constituting the shock torque prevention valve, only the related dimensions of the needle valve and the piston are managed so as to be within a predetermined range. The clutch shock when switching the clutch from the disengaged state to the connected state can be reduced to a predetermined value or less, and the number of parts requiring strict dimensional control can be reduced.

[Brief description of the drawings]

FIG. 1 is a sectional view of a clutch anti-shock valve according to an embodiment of the present invention, FIG. 2 is a cross-sectional view of a clutch anti-shock valve according to another embodiment of the present invention, and FIG. FIG. 2 is a cross-sectional view of the clutch shock prevention valve according to the embodiment of the present invention. 2 ... Clutch pedal, 4 ... Master cylinder, 6,6 ',
6 ″… Clutch anti-shock valve, 6a …… First liquid chamber, 6b
…… Second liquid chamber, 8 …… Operating cylinder, 12…
... Cylinder body, 14 ... Needle valve, 16 ... Piston, 16a ... Through hole, 18 ... Spring, 22a, 22b ... Buffer member.

Claims (3)

(57) [Claims] An anti-shock torque valve disposed in a hydraulic circuit between a master cylinder operated by a clutch pedal and an operating cylinder for operating a withdrawal lever, having a cylindrical chamber therein. A cylinder body, a piston which is slidably fitted into a cylindrical chamber and divides the two into a first liquid chamber and a second liquid chamber, a needle valve fixed to the cylinder body, and a piston. A spring pushing in the direction of the second liquid chamber;
And the first liquid chamber is connected to the master cylinder,
The second fluid chamber is connected to the operating cylinder, and the piston is provided with a through hole for communicating the two fluid chambers with each other. The needle valve extends into the through hole and is formed between the through hole and the needle valve. The liquid passage is largest when the piston is pushed to the stop position by the spring, and becomes narrower as the piston moves toward the first liquid chamber. A stopper portion, a part of the needle valve is cut out, and a flow passage connecting the master cylinder and the first liquid chamber is formed between the needle valve and the cylinder body. 2. The anti-shock torque valve for a clutch according to claim 1, wherein at least one of the piston and the needle valve is made of plastic. 3. The shock torque prevention valve for a clutch according to claim 1, wherein a buffer member made of a soft material is provided in the second liquid chamber at a position facing the piston.