JPH0567467B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a brake control device equipped with a valve device that maintains and releases brake pressure in response to actuation of a clutch device by a hydraulically actuated clutch actuating device. .

(Prior art) As shown in, for example, Japanese Utility Model Publication No. 58-24615, this type of device is provided between a brake master cylinder and a brake wheel cylinder, and hydraulic fluid flows from the brake wheel cylinder to the brake master cylinder. The valve device includes a valve seat provided toward the brake wheel cylinder side, a valve body that can be seated on and taken off from the valve seat, and a valve device that engages and operates the valve body. A device is known that is equipped with an operating mechanism that allows the valve seat to be seated in accordance with the operation of the device, and when the clutch pedal is depressed while the brake is applied,
In response to the clutch being disconnected in the clutch device, the valve element in the valve device is seated on the valve seat to prevent brake pressure from being released, and even if the brake master cylinder stops operating, the brake pressure is maintained as it is. When going uphill, the brake is held with the clutch pedal depressed, and then when the clutch pedal is gradually released to start, when the clutch device is in a half-clutch state, the valve body of the valve device is pressed against the valve seat. The pressure that was being held is released by making the person leave the seat.

(Problems to be Solved by the Invention) In the above-mentioned valve device, a piston that receives the pressure of the clutch master cylinder at one end against the biasing force of the preload spring is used as the operating mechanism of the valve device. The time to release the pressure is when the piston serving as the operating mechanism has moved to a predetermined position when the pressure and the biasing force of the preload spring are balanced. Therefore, if the clutch device uses a diaphragm spring to ensure the frictional force of the clutch facing, the change in fluid pressure until the half-clutch state is reached is not constant; There is a problem in that the pressure becomes the same as the current state, causing a malfunction and prematurely releasing the brake pressure.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a brake control device that can release brake pressure at an appropriate time in response to a hydraulic clutch actuation device.

(Means for Solving Problems) In the present invention, the clutch master cylinder has a sub-pressure chamber that discharges hydraulic fluid in accordance with its operation, which is independent of the main pressure chamber that supplies hydraulic fluid to the clutch operating cylinder. The operating mechanism of the valve device includes a variable volume control chamber connected to the auxiliary pressure chamber, and a control chamber that completely connects the clutch in response to changes in the amount of hydraulic fluid supplied to the control chamber. A control piston is provided that is moved between a corresponding initial position and a maximum actuation position that corresponds to disengagement of the clutch, and a control piston is provided between the control piston and the valve body that allows the control piston to move beyond a predetermined position from the initial position. an actuation member that forcibly displaces the valve body from the valve seat until the valve body moves to the maximum operation position, and allows the valve body to sit on the valve seat when the control piston moves from the predetermined position to the maximum operation position; I decided to set it up.

(Function) The control piston moves not in proportion to the hydraulic pressure acting on it, but in proportion to the amount of pressure fluid supplied from the clutch master cylinder.
The control piston moves to a position according to the operation of the clutch master cylinder, and on the other hand, since the clutch master cylinder and clutch operating cylinder operate in conjunction with each other with a certain amount of fluid interposed between them, the clutch operating cylinder The inner piston and the control piston move in conjunction with each other with the master cylinder interposed. When the piston of the clutch operating cylinder is in the half-clutch position, the control piston is in a predetermined position, so that when the clutch device is engaged,
When the clutch is partially engaged, the control piston opens the valve system and releases the brake.

(Effects of the Invention) According to the present invention, the brake pressure is released when the clutch device is in the half-clutch state, so the brake pressure can be released at an appropriate time without having to release the brake pressure early. Furthermore, the present invention can be applied regardless of the type of clutch device. Furthermore, since the control is proportional to the amount of movement of the hydraulic fluid, even if the hysteresis of the clutch actuating device is large, proper control can be performed in proportion to the actuation of the clutch operating cylinder.

(Embodiment) FIG. 1 is a sectional view showing a clutch master cylinder in one embodiment of the present invention, and FIG. 2 is a sectional view showing a control valve used in combination with the master cylinder of FIG. 1. .

In FIG. 1, the clutch master cylinder is
1, this master cylinder 1 has a stepped hole 2
A stepped piston 4 is movably inserted into the stepped hole 2.

The stepped piston 4 has a head portion 5 that fits into the small diameter portion 2a of the stepped hole 2, and a main body portion 6 that fits into the large diameter portion 2b.
The tip small diameter part 6a of the main body part 6 is press-fitted into the small diameter part of the stepped hole 5a provided on the right side of the head part 5, and the small diameter part of the stepped hole 5a and the main body part are connected together. A cylindrical coupling member 7 is press-fitted across the hole 6b.

A lip-type sealing member 8 is attached to the left outer periphery of the head 5, and forms a main pressure chamber 10 that is connected to a clutch operating cylinder (not shown) through a discharge hole 9.
A loosening hole 11 formed slightly to the left of the sealing member 8 communicates with the interior of a boss portion 12 that communicates with the interior of a hydraulic fluid reservoir (not shown). Further, a small hole 5b is formed in the flange-shaped portion of the head 5 to connect the right end side of the sealing member 8 to the supply chamber 13.

The replenishment chamber 13 is formed on the outer periphery of the small diameter portion 6a of the main body portion 6 on the right side of the head portion 5, and is inserted into the boss portion 1 through a replenishment hole 14 formed so as to overlap the right end portion of the head portion 5.
2 and the small diameter portion 6 of the main body portion 6
A is communicated with the hole 6d through a through hole 6d provided at the left end of the continuation shaft portion 6c.

The main body part 6 has a lip-type sealing member 15 on the outer periphery of the right end.
, and a lip-type sealing member 17 that is supported by a back-upper 16 that engages with the stepped portion 2c of the stepped hole 2 and seals between the shaft portion 6c and the large diameter portion 2b, and an auxiliary pressure chamber 18 is formed between the lip-shaped sealing member 17 and the The auxiliary pressure chamber 18 is divided into the shaft portion 6
It communicates with the hole 6b through a loosening hole 6e formed in c, and also communicates with a control port 26 of a control valve 25 (valve device), which will be described later, through a discharge hole 19. A return spring 21 tensioned between the large diameter portion 6f of the main body portion 6 and a spring receiver 20 supported by the back up pad 16 via the sealing member 17 causes the push rod 2 to be
2 and an annular plate member 23 to a return position where it abuts against a stopper 24.

Next, the control valve 25 will be explained with reference to FIG.

The control valve 25 has a stepped hole 27 that penetrates in the left-right direction.
The opening of the stepped hole 27 is closed by a plug 29, 30, respectively.

A medium diameter part 27b is formed on the left side of the small diameter part 27a in the middle of the stepped hole 27, and a large diameter part 27c is formed on the right side.
A separator 32 is inserted between the plate 31 and the separator 32 and the plate 31.
A rod 33 is disposed movably through the plate 31, and the rod 33, which serves as an operating member, is biased to the right by a spring 35 stretched between a retaining ring 34 attached to the right end and the plate 31. . The left end of the rod 33 is connected to a support member 3 having an L-shaped half cross section and supported by a stepped portion 27e formed on the medium diameter portion 27b side of the small diameter portion 27a.
6 and a seat member 37 that is fitted onto the support body 36 while sealing the space between the support body 36 and the main body 28, and protrudes into the inside diameter portion 27b.

Inside the medium diameter portion 27b, a plug 29 and a medium diameter portion 27 are provided.
b. A ball guide 38 is provided which is fixed between the step part between the small diameter part 27a and fits onto the seat member 37,
A ball 39 is housed inside the ball 39, which is movable by its own weight on an uphill road and rolls to be seated on the seat member 37 and the support body 36. In addition, ball 39
On the other hand, the above movement is performed by aligning the traveling direction of the vehicle with the axis of the middle diameter portion 27b, and by arranging the left side of the middle diameter portion 27b to be on the front side in the traveling direction. .

The inside of the ball guide 38 is connected through the gap between the rod 33 and the support 36 and the notch 32a of the separator 32 to a connection hole 40 that is connected to a brake master cylinder (not shown). The notches 38a, 38a communicate with connection holes 41a, 41a, which are connected to brake wheel cylinders of a wheel brake device (not shown).

A control piston 43 is movably inserted into the large diameter portion 27c and is biased to contact the stepped portion 27f by a spring 42 disposed between the plug 30 and the control piston 43.
A control chamber 45 is partitioned by a lip-type sealing member 44 attached to the outer periphery of the small diameter portion 27a. This control chamber 45 is located in a notch 43 of the control piston 43.
a and the right end of the small diameter portion 27a through the control port 26.
is connected to. The control piston 43 is located in the control chamber 45
The step part 2 can be moved toward the plug 30 side against the spring 42 by the pressure fluid supplied to the control chamber 45, and when the pressure fluid is not supplied to the control chamber 45, the stepped part 2
7f and the rod 33, displacing the rod 33 to the farthest left, making the left end contact the ball 39, and moving the ball 39 to the seat member 3.
I'm keeping it away from 7. When pressurized fluid is supplied to the control chamber 45, it moves toward the plug 30, allowing the rod 33 to be displaced to the right, and if it moves a predetermined amount before coming into contact with the plug 30, the rod 33 is fully moved. the clutch device is fully engaged when the control chamber 45 is supplied with pressurized fluid until the control piston 43 abuts the plug 30. in the shut-off position (maximum operating position). Conversely, the control piston 43
When the amount of fluid corresponding to the decrease in the volume of the control chamber 45 from 0 to the small diameter portion 27a side returns to the clutch master cylinder side, the control piston 43 seats the ball 39 via the rod 33. It is designed to be separated from the member 37.

Additionally, in FIG. 2, a indicates a sealing member.

The operation of the above embodiment will be described below.

Assume that the vehicle is currently traveling on an uphill road. Then, since the brake is not applied and the clutch is also engaged, each member is in the position shown. That is, in the clutch master cylinder 1, the return spring 2
When the piston 4 is in the position where it engages with the stopper 24 with a biasing force of
e, hole 6b, through hole 6d, supply chamber 13, supply hole 14
Pressure is released through. Therefore, in the control valve 25, since there is no pressure in the control chamber 45, the spring 42
The control piston 43 comes into contact with the stepped portion 27f and the rod 33 due to the urging force, and the ball 39, which attempts to move due to its own weight, is blocked by the rod 33 and cannot be seated on the seat member 37.

When the brake is applied in this condition, pressure fluid from the master cylinder flows from the connection hole 40 to the notch 3.
2a, passing through the gap between the support body 36 and the rod 33, inside the ball guide 38, and through the notch 38a in order,
It is supplied to the brake wheel cylinder through the connection holes 41a and 41b, and the brake starts to be applied.

When the brake is sufficiently applied, the clutch master cylinder 1 is operated to disconnect the clutch, and the stepped piston 4 is moved to the left under pressure from the push rod 22, and the sealing member 8 is connected to the loosening hole 11. Communication with the main pressure chamber 10 is cut off, and the sealing member 17 cuts off communication between the loosening hole 6e and the sub-pressure chamber 18, thereby generating pressure in each pressure chamber. Main pressure chamber 1
The pressure fluid generated in the auxiliary pressure chamber 18 is supplied to the clutch operating cylinder to completely shut off the clutch device, and the pressure fluid generated in the auxiliary pressure chamber 18 is
The control piston 43 moves until it comes into contact with the plug 30, and as the rod 33 moves following the control piston 43, the ball 39 moves under its own weight, and the seat member 37 is moved. sit down.

If the operation of the brake master cylinder is stopped in this state, the pressure on the master cylinder side is released from the contact area between the ball 39 and the seat member 37, but the pressure on the wheel cylinder side is 36, it is held as it is.

In the operations up to this point, the vehicle operates the clutch master cylinder on an uphill road to shut off the clutch device and maintain the hydraulic pressure in the wheel cylinders to keep the vehicle stopped.

After this, when the operation of the clutch master cylinder 1 is gradually released for starting, the stepped piston 4 of the master cylinder 1 gradually moves from the operating position to the position where it engages with the stopper 24, and The volumes of the pressure chamber 10 and the sub-pressure chamber 18 are gradually increased.

Due to the increase in volume of the main pressure chamber 10, pressurized fluid returns from the clutch operating cylinder to the main pressure chamber 10 such that the piston of the clutch operating cylinder moves in the direction of clutch engagement.
And in proportion to this, the control chamber 45 of the control valve 25
The pressure liquid returns to the auxiliary pressure chamber 18 from the control piston 4
3 moves away from the plug 30 in proportion to the amount of liquid returned to the auxiliary pressure chamber 18. Main pressure chamber 1
As the volumes of the pressure chamber 18 and the pressure chamber 18 continue to increase, the clutch operating cylinder moves to the half-clutch position, and the control piston 43 contacts the rod 33 and releases the ball 39 via the rod 33.
The ball 39 is moved to a position where it comes into contact with the seat member 37, and the ball 39 is separated from the seat member 37. As a result, driving force is transmitted to the drive wheels and the brakes begin to loosen. After this, in the clutch operating cylinder, the piston advances the clutch connection, and the control valve 25 further loosens the brake, so that the vehicle can finally start without backing up on the uphill road, and the clutch master cylinder 1 When the clutch device is completely deactivated, the clutch device is fully connected, and the control valve 25 completely releases the brake fluid pressure, so the vehicle enters a normal running condition and each member shown is in the position shown. Return.

In these above-described embodiments, the master cylinder 1
, i.e., fluid movement between the master cylinder 1 and the clutch operating cylinder, and between the master cylinder 1 and the control valve 2.
5, and thereby the movement of the control piston 43 is linked to the movement of the piston of the clutch operating cylinder. , it can be matched accurately when the clutch is in a half-clutch state. Therefore, even if there is a large change in operating pressure when the clutch device is disconnected or connected,
Even if it is small, brake pressure can be released properly and performance is stabilized.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a clutch master cylinder according to an embodiment of the present invention, and FIG. 2 is a sectional view of a control valve used in combination with the clutch master cylinder of FIG. 1. 1...Clutch master cylinder, 18...Sub-pressure chamber, 25...Control valve, 33...Rod, 37...
... seat member, 39 ... ball, 43 ... control piston, 45 ... control chamber.

Claims (1)

[Claims] 1. A valve device is provided between a brake master cylinder and a brake wheel cylinder and is capable of blocking movement of hydraulic fluid from the brake wheel cylinder to the brake master cylinder, and this valve device is provided on the brake wheel cylinder side. A brake control device comprising: a valve seat provided in front of the valve; a valve element that can be seated on and removed from the valve seat; and an actuation mechanism that allows the valve element to be seated on the valve seat in accordance with the operation of a clutch actuating device. The clutch master cylinder is provided with an auxiliary pressure chamber that discharges hydraulic fluid in response to its operation, independent of the main pressure chamber that supplies hydraulic fluid to the clutch operating cylinder, and the operating mechanism includes A control chamber with a variable volume connected to the sub-pressure chamber is divided, and the initial position corresponds to full engagement of the clutch and the maximum position corresponds to disconnection of the clutch, depending on changes in the amount of hydraulic fluid supplied to this control chamber. A control piston is provided that is moved between the control piston and the valve body, and a control piston is provided between the control piston and the valve body until the control piston moves from the initial position beyond a predetermined position to the maximum operation position. A brake control device including an actuation member that forcibly separates the valve body from the valve seat and allows the valve body to sit on the valve seat when the control piston moves from the predetermined position to the maximum operating position side. .