JPS61291258A - Brake device - Google Patents

Abstract

PURPOSE:To enable pads to move positively in accordance with change in the direction of a braking force by providing a low frictional member between brake pads and members which press the said pads in a braking device where a brake holding device is controlled by a detecting device which detects the time when a car is stopped on an uphill road with a brake applied. CONSTITUTION:While a car is running on an uphill road, if a brake pedal is pressed, a braking force is provided in such a way that fluid pressure from a master cylinder is applied to a cylinder 2 of a disc brake 80 allowing brake linings 9 and 12 of pad plates 8 and 11 to be pressed with pressure against both sides of a disc rotor 10. Accordingly, when the car is stopped, the disc rotor 10 which rotates together with wheels, intends to rotate reversely causing the pad plates 8 and 11 to move to the right overcoming the resilient force of a retainer 19. This allows a switch 20 for the actuation of a brake holding valve to be turned on. In this configuration, low frictional parts 82 and 84 in a sheet form is stuck on the surface opposite to the rotor (10) side of the pad plates 8 and 11 through shims 83 and 85 so as to make sure of the actuation of the switch 20 through the pad plates 8 and 11.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a brake system for automobiles, etc., and particularly to a brake system that allows easy starting on a road.

[Conventional technology and its problems]

For example, in the brake device disclosed in Utility Model Application No. 55-43905, when the clutch pedal is depressed, a valve device linked to the clutch pedal is closed, and hydraulic pressure is applied to the wheel cylinder of a car on the road. I'm trying to hold it and hold the brakes.

That is, the driver can keep the car stopped on the road even if he takes his foot off the brake pedal, but he must continue to press the clutch pedal.

When starting the car, the clutch pedal is gradually released, that is, the clutch is left in a half-clutch state, and the accelerator pedal is depressed to increase the engine speed and start the car.

As mentioned above, when a car is stopped on a road, the valve device is closed by depressing the clutch pedal, and the valve is opened by returning the clutch pedal to the time of starting. When various parts such as clutch 7 acing wear out, the valve opening timing is constant relative to the position of the clutch pedal, but sufficient driving force is not transmitted from the engine to the wheels via the clutch 7 acing to start the vehicle. The timing of transmission will vary. In other words, the brake is released before the driving force is sufficiently transmitted to the wheels.

This is because, in the above-mentioned conventional system, the brake is released when the clutch pedal is in a so-called half-clutch position in the clutch device, and if the clutch 7 acing is worn out, etc. (This occurs because the position where the clutch is in the half-clutch state changes, and the release timing is not changed in response to this change.)

In this way, when sufficient driving force is transmitted to the wheels,
If the timing at which the brakes are released is shifted so that the latter is earlier and the former is later, the vehicle will move backwards when starting on the slope, leading to all sorts of accidents.

In view of the above problems, at least one piping from the master cylinder to the wheel cylinder is provided for the purpose of providing a brake device that can perform appropriate operation depending on the condition of a single wheel or the vehicle body when stopping and starting an automobile, etc. The system is equipped with a brake holding valve that can maintain full pressure on the wheel cylinder side in response to external commands, and a detection system that operates by detecting movement of the disc brake pad pressed against the rotor based on a change in the direction of braking force. A brake device has previously been proposed in which a device is provided and the command is given to the brake holding valve based on the operation of the detection device.

However, in the above braking device, if the force that attempts to move the pad due to a change in the direction of braking force application is smaller than the frictional force between the pad and the member that presses the pad, the pad will not move. In this case, the detection device will not work,
It becomes impossible to maintain braking force.

[Problem that the invention seeks to solve]

The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a brake device that can be reliably moved in response to changes in the direction of action of the total brake force of the pad.

[Means for solving problems]

The above purpose is to provide at least one piping system from the master cylinder to the wheel cylinder with a brake holding valve that can maintain the pressure on the wheel cylinder side in response to an external command; The brake device is provided with a detection device that is activated by detecting a movement based on a change in the direction of brake force application of the pad, and is configured to apply the command to the brake holding valve based on the operation of the detection device, the pad and the pad concerned. This is achieved by a brake device that is provided with a low-friction member that reduces the movement resistance of the pad between the member that presses the pad and the member that presses the pad.

[For production]

When a car comes to a stop on the road by applying the brakes, one of the pads is moved in one direction. A detection device detects this movement and fully closes the holding valve, thereby maintaining hydraulic pressure in the brake device. When a rotational force is applied to the wheel, that is, the disc rotor, in the forward direction in order to start the automobile, the pad is moved in the other direction. The detection device detects this, opens the holding valve, and releases the hydraulic pressure of the brake device. In this way, the brake can be held and released depending on the condition of the wheels.

Since a low friction member is disposed between the pad and the member that presses the pad to reduce the movement resistance of the pad,
The pad is applied in the direction in which the braking force is applied.
This will be explained with reference to FIGS.

In the figure, the main body (1), which is shown as a whole by a square during a disc play, is composed of a cylinder part (2) and a caliber part (3), and has a known internal structure. Cylinder part (2)
is integrally formed with an input cap (4) that receives hydraulic pressure from the master cylinder, and the piston υ in the cylinder part (2) slides forward through the cylinder hole in response to the hydraulic pressure. , a cylinder part (2), and a caliper part (3).The main body (IJ) is configured to move in the opposite direction to the piston due to reaction force.

From the cylinder part (2), a pair of arm parts (5 m
) (5b) protrude, and these are each guided by a guide device (6Jl bar 6b) so as to be slidable in 9 front and rear directions. The guide devices (6a) (6b) are supported by arm portions (7a) (7b) of a bifurcated base member (7) fixed to the vehicle body.

A pad plate (8) is in contact with the tip of the piston member υ in the cylinder part (2) of the main body (II) via a low-friction member □ and a shim g!3t. The lining (9) is attached during play. Part of the caliber (
3) straddles the disc rotor 0Qt that rotates with the wheel, and its 7 oak-shaped arms (3a) (3b)
is in contact with the other pad's base via the low friction member (goods) and shim 4. A brake lining □□□ is also attached to this pad plate (6). Disc rotor aQ
is interposed between the brake linings (9) and (b) with a small gap between them. Since the guide devices (6a) and (6b) have the same configuration, only one part (6a) will be described.

In the guide device (6a), the arm portion (5) of the main body (1)
A sleeve (to) is fitted into the hole formed in a), and the bolt α4t is inserted through the sleeve and screwed onto and tightened to the arm portion (7a) of the base member (7). ), the bolt (141, sleeve (to) is the base member (7
).

Both ends of the sleeve are covered by elastic rubber boots (6).

The other guide device (6b) is configured similarly, and the main body (IJ
is slidably guided by these in the p-axis direction.

The pad plates (8) and (b) are an output side retainer A8 (to) and an input side retainer CII, which are made by bending leaf springs, respectively.
4, it is elastically supported by the arm portions (7a) and (7b) of the base member (7), and is movable by a predetermined amount in the axial direction and the circumferential direction indicated by arrow A. Note that the output side retainer (to) may be omitted in some cases in order to increase the amount of movement of the pad plate (8) in the circumferential direction.

A recess extending in the circumferential direction is formed in the arm portion (7b) of the base member (7), into which the switch 4 is fitted. The actuation rod (20a) of the switch (7) is inserted through a notch (19) formed in a bent part (19b) of a part of the retraction side retainer 4, and then inserted into the other bent part (19a) of the same retainer 4. ).The bent portion (19a) (1
9b) are in elastic contact with the side surface of the pad plate (8) αυ and the inner surface of the arm portion (7b) of the base member (7), respectively.

The operating rod (20a) of the switch (7) is biased to the left in FIG. 1 by a spring built into the switch 4, and is in elastic contact with the bent portion (19a) of the retainer.

The braking lining (9) of the pad plate (8) will cause the disc rotor (IQ) to drag even when inactive during play.
However, at this time, the pad plate (8) may be biased to the right in FIG. The sum of the elastic force of the portion (19a) and the spring force of the spring built into the switch and biasing the actuating rod (20a) to the left shall be sufficiently large.

A rubber strip and a rubber ring C23+ are interposed between the switch 4 and the inner wall surface of the recess @, so that the switch (E) is isolated from the vibration force that the base member (7) receives, and It is insulated from the member (7).

The base member (7) is equipped with a hole (
17a) and (17b), it is fixed to a part of the vehicle body (not shown). Note that ■ is a lead wire, and (c) is a bleeder.

As mentioned above, the pad plate (8) (for IIJ, there is a shim ta
n5) is adhered thereto, and a sheet-like low-friction material is further adhered thereon, and this low-friction member may be made of, for example, thiamin.

Sim g again! 3 (f) is obtained by coating both sides of a thin metal plate with rubber, as is known, and serves to prevent brake squeal.

The disc brake unit in this embodiment is constructed as described above. Next, the entire brake system including the disc brake unit will be explained with reference to FIG. 4.

In FIG. 4, a brake pedal C3 is connected to the tandem master cylinder Gll, and its first hydraulic pressure generating chamber is connected to the wheel cylinders of the rear wheels (34a) (34b) through a pipe connection. The second hydraulic pressure generation chamber is connected to a solenoid valve (
) and pipe 1.37) through the front wheel (38a) (,
38b) ID wheel cylinder is connected. Front wheel (3
The above-mentioned disc brake is used for the 8 wheel cylinders.

Disc brake:? The -100 lead wire c211 of the switch (e) in norlenoid (36a)
, the negative terminal of the battery (
Connected to 47J.

The solenoid valve (to) is a two-position solenoid switching valve, and when the solenoid (36a) is not energized, it assumes the D position under the action of the spring (36b,), thereby communicating the pipe line - with I3η. However, when the solenoid (36a) is energized, it takes the position E, and the pipe *c! Let a and 07) be out of communication.

Next, details of the solenoid valve (to) will be explained with reference to FIG.

A lid body (goods) equipped with a seal ring is fitted into the right end opening of the cylindrical body (43), and a master cylinder connection hole (c) is formed in it. A lid body 5υ equipped with a ring is fitted, and a wheel cylinder connection hole 6? is connected to this.The connection hole (451521 has a pipe field c in Fig.
Three forces are connected.

Inside the cylinder (43 is a piston (43) made of a magnetic material that can be slid freely).
4e is fitted, and is biased to the right by a spring disposed between this and the lid 511, and in the normal state shown, is in contact with the inner end surface of the lid 511. An axial passage A7) is formed in the piston μe in communication with the connection hole of the lid, and a plurality of passage decoys are further formed in the radial direction in communication with this.

The diameter of the left side of the piston (on the piston) has been reduced, and an annular master cylinder crown (63t) is formed around this.

This pressure chamber is always in communication with the master cylinder connecting hole (c) via the passage α7) decoy. The above-mentioned spring bar is arranged in this pressure chamber.

A recess (2) is formed in the radial direction of the lid (51), into which the valve casing (2) is fitted with a seal ring (55t). A spring (valve ball 6 ? which is urged against the lower blade by 50 ) is disposed inside the valve casing ( 2 ), and in the normal state shown in the figure, the through hole ( 5 ) formed in the valve casing ( b )
81 is closed.

The lid body 5]) is further formed with an axial passage diagram, and this right end opening is connected to the valve ball (4) fixed to the left end of the piston (46).
It is facing 9. In other words, it works as a valve seat for valve ball i4!1. The axial passage (to) is constantly in communication with the wheel cylinder connection hole 6z via a plurality of small holes formed in the peripheral wall of the valve casing 1541.
The through hole 5g formed at 541 is always in communication with the master cylinder pressure chamber via the groove (59) formed at the right end of the lid 6υ.

A coil 1611 is wound around the cylindrical body (43), and the lead wire from this is connected to the electric line (41a and 41b) in FIG. 4. That is, the coil 6υ is connected to the solenoid in FIG. (36a). Also, the spring 61 corresponds to the spring (36b).
In Figures W and 5, the splash (T) and the valve ball mark inside the valve casing 64 constitute a check valve, allowing liquid flow from the master cylinder side to the wheel cylinder side, but prohibiting the reverse. The function of this check valve is omitted from illustration in FIG.

The embodiment of the present invention is configured as described above, and its operation, effects, etc. will be explained next.

Now, it is assumed that the automobile is climbing the slope St-A shown in FIG. 6, and the brake pedal CC53T-mi is depressed to stop. In FIG. 6, arrow F is the direction of travel of the automobile, and arrow A is the direction of rotation of the single wheel.

The pressure fluid from the master cylinder 6υ passes through the pipe G1 to the rear wheel (
(34a
3'rIt- and is supplied to the front wheels (38a) (38b) O-wheel cylinders. That is, in FIG. 5, connection hole t45) - axial passage + 47) → radial passage (
Pressure fluid is supplied from the master cylinder side to the wheel cylinder side via 48 → master cylinder royal house 69 → axial passage (goods) → connection hole 5.

Brakes are applied to the wheels (34a), (34b), (38a), and (38b) to decelerate the vehicle. In the front wheel (38b), the gray bearing (9) U of the pad plate (8) ση comes into pressure contact with the disc rotor, and a frictional force is generated between them. As a result, a brake reaction force acts on the pad (8) in the direction of arrow B as shown in FIG. That is, in FIG. 1, the pad plate (8) receives a biasing force toward the left. Therefore, since the switch (A) remains off, the solenoid (36a,) of the electromagnetic valve (G) remains de-energized and continues to take the D position. That is, the fifth
In the figure, each part of the solenoid valve continues to take the position shown.

When the car stops on a slope, the disc rotor QO, which was rotating together with the wheels, receives a rotational force in the opposite direction to that when the car was running, and the disc rotor aQ and pad plate (8) qυ
The frictional force acting between the two is reversed. As a result, in FIG. 1, the pad plates (8) and (11) are pushed to the right by overcoming the sum of the elastic force of the retainer α and the spring force of the spring incorporated in the switch (E). The actuation a-rad (20a) is pushed in, the switch handle is turned on, the solenoid (36a) of the solenoid valve (to) is energized, and the solenoid valve (to) is switched to the E position.

That is, in FIG. 5, the coil is energized, and the piston (c) moves to the left under the magnetic attraction force, and the valve ball II is seated at the open end of the passage.

The wheel cylinder side and the master cylinder side are cut off. In this state, when the driver releases the pedal force on the brake pedal C33, the brake fluid flows back from the wheel cylinder of the rear wheel (34a and 34b) to the master cylinder 6υ, but the solenoid valve (to) is in a shut off state. Therefore, the front wheel (38a
) (The brake fluid does not flow back from the wheel cylinders 38b and 38l, and the pressurized fluid is held there. This allows the vehicle to remain stopped on a slope.

In order to start the car, when the gears are changed, the clutch pedal is in the half-clutch state, and the accelerator pedal is depressed, the driving force is transmitted to the disc rotor αQ of the front wheel (38b), and the drive force is transmitted to the disc rotor αQ of the front wheel (38b). The frictional force between them is reversed again, and the reaction force of the play cow becomes the input direction button, and the east pad plate (8) is pushed to the left and assumes the position shown in FIG. In other words, the switch...is turned off, and the solenoid (to) of the solenoid valve (to) is turned off.
The power supply to 36 is cut off. The solenoid valve (to) takes the position D again, and in FIG. 5, each part takes the position shown, and the master cylinder side υ side and the wheel cylinder side are communicated. The pressure fluid held in the cylinder part (2) passes through the solenoid valve (G) in the state shown in the figure and enters the master cylinder 6υ.
Reflux to. The brake is then released and the car starts.

In the above, when the brake pedal l3at- is depressed to further increase the braking force when the vehicle is stopped on a climbing road, the check valve in the valve casing (54) opens as shown in FIG. That is, the valve ball I5η is pushed upward against the spring force of the spring 15G by the hydraulic pressure from the master cylinder pressure chamber, and is separated from the valve seat, thereby communicating the master cylinder side and the wheel cylinder side. This allows the braking force to be further increased.

This embodiment operates as described above, but also has the following effects.

That is, in Fig. 2, when the brake is applied, the pad plate (8) (lυ) is pressed against the piston υ and arm parts (3a) (3b) via the low friction member @[4], so the brake is ! ? When the direction of action of the frictional force changes, the pad plate (8) east can easily move in the circumferential direction. Thereby, the switch (4) can be turned on and off reliably, and the operability of the device can be improved.

Conventionally, the piston and the arm part (38) (3b) and the t-pad plate (8) were pressed only through the shim can, so the frictional resistance between them was large and the friction force of the play ΦM changed. However, there was a risk that the pad plate (8) qη would not move accordingly. However, according to this embodiment, since the surfaces to be pressed by the piston g33J and the arm parts (3a) and (3b) are made of low friction members@2 (Incorporated), the frictional resistance between them is small and the pad plate (8) qη can easily move in the circumferential direction while being pressed.

The embodiments of the present invention have been described above, but of course the present invention is not limited thereto, and various modifications can be made based on the technical idea of the present invention.

For example, in the above embodiment, only the front wheels are held in play, but if this is insufficient, the braking force may be maintained on the rear wheels as well.

In this case, a valve device that receives the brake fluid pressure of the front wheels and closes the valve in response to the brake fluid pressure of the front wheels may be provided between the master cylinder and the rear wheels, as has already been proposed.

Further, in the above embodiment, the switch (2) was provided on the arm portion (7b) of the base member (7) in the disc brake field, that is, on the input side of the disc rotor αq, but it may be provided on the output side. . In this case, the actuating rod (20 m
) is pushed in, the switch (7) is turned off, but when the switch (7) is turned on, the circuit may be configured such that power to the solenoid of the electromagnetic valve (to) is cut off.

Further, in the above embodiments, movement of the pad plate in the circumferential direction is detected, but movement in the radial direction may also be detected.

〔Effect of the invention〕

As described above, according to the brake device of the present invention, it is possible to maintain a stopped state of the vehicle even if the clutch pedal is not continuously depressed, and even when the clutch plate is worn out, the pedal operation can be continued. It is possible to reliably obtain the effect that there is no timing difference between the timing and the actual movement of the wheels or the vehicle body in any case.

[Brief explanation of drawings]

FIG. 1 is a front view of a disc brake in a brake device according to an embodiment of the present invention, the second figure is a plan view of the same, FIG. 3 is a rear view of the same, FIG. 4 is a piping system diagram showing the entire brake device, FIG. 5 is a sectional view showing details of the solenoid valve in FIG. 4, and FIG. 6 is a schematic side view of a wheel on a slope to show the operation of the same embodiment. In the figure,

Claims (1)

[Claims] at least one from the master cylinder to the wheel cylinder
A brake holding valve that can maintain the pressure on the wheel cylinder side in response to an external command is installed in each piping system, and is activated by detecting movement based on a change in the direction of braking force applied to the disc brake pad that is pressed against the rotor. In the brake device, a detection device is provided, and the command is given to the brake holding valve based on the operation of the detection device, the movement resistance of the pad is reduced between the pad and a member that presses the pad. A brake device equipped with low-friction components.