JP2544110B2 - Break control device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a brake control device for a brake device equipped with a device that facilitates a starting operation on an uphill road of a vehicle or the like.

[Conventional technology and its problems]

For example, in the brake device disclosed in Japanese Utility Model Laid-Open No. 55-43905, by depressing a clutch pedal, a valve device interlocked with the clutch pedal is closed, and hydraulic pressure is applied to a wheel cylinder of an automobile on an uphill road. Hold it and hold the brake. That is, the driver can stop the vehicle on an uphill road even if he releases his foot from the brake pedal, but he must continue to depress the clutch pedal.

When the vehicle is started, the clutch pedal is gradually returned, that is, in the half-clutch state, the accelerator pedal is stepped on to increase the engine speed to start the vehicle.

As described above, when stopping an automobile on an uphill road, the clutch pedal is depressed to close the valve device, and the clutch pedal is opened by returning at the start,
When various members related to the valve device and the clutch pedal, such as wear of the clutch facing, occur, the timing of opening the valve with respect to the position of the clutch pedal is constant, but the engine moves from the engine to the wheels via the clutch facing. Because of this, it will be out of time when a sufficient driving force is transmitted. That is, the brake that releases the sufficient driving force to the wheels is released.

In the above-mentioned conventional one, the brake pedal is set to be released when the position of the clutch pedal is in a so-called half-clutch state at the clutch position, and the clutch facing is worn. Then, the position is changed so as to be in the half-clutch state, and the release timing is not changed according to this change.

In this way, when the time when the sufficient driving force is transmitted to the wheels and the time when the brake is released deviate so that the latter is early and the former is late, the vehicle moves backward when starting on an uphill road. Will cause an accident.

In view of the above problems, the present applicant has previously proposed a brake control device capable of performing an appropriate operation according to the state of a wheel or a vehicle body when the vehicle is stopped or started, and a rear wheel. Detection device that detects the action of the rotational force in the reverse direction of the vehicle by the change in the action direction of the brake friction force on the rear wheel, and the action of the brake device that produces the braking force on the wheel in response to the driver's operation. A brake control device provided with a holding device capable of holding the device even if the operation is released based on the detection of the device is proposed.

However, this is not a problem in the normal case where the car stops on a slope, but depending on the slope angle of the slope or the suspension mechanism of the car body of the car, when a sudden brake is applied, the switch provided as the above-mentioned detection device on the rear wheel is turned on. In some cases, it may not be maintained.

That is, in the above-mentioned case, when the brake is suddenly applied, the so-called nose dive is reduced in the vehicle, and the rear wheel side of the vehicle body is in a posture of floating from the ground. After that, it sank by rocking back, and nose dive by rocking again. On the first nose dive, the switch remains off, but it turns on with the retraction subsidence. However, the switch is turned off at the next nose dive.
The switch does not turn on steadily when the car is stopped.

Eventually, the vehicle is kept stopped by the back torque on the front wheels due to the repeated swinging of the vehicle body, so that the back torque sufficient to turn on the switch does not act on the rear wheels, and the holding device does not operate. When the brake operation is released in this state, the vehicle will move backward.

Therefore, in order to deal with such a situation, the applicant previously proposed, in the proposal, to a holding device that disconnects the brake device side of the rear wheel from the master cylinder when the switch (detection device) is turned on, and a brake device for the front wheel. A valve device is provided to move forward and backward between the holding device and the master cylinder in response to a change in the pressure supplied to the holding device, and delay the pressure release on the holding device side from the brake device side on the front wheels when the brake operation is released. I decided.

That is, when pressure is rapidly supplied from the master cylinder to the brake device of each wheel, the valve device blocks only the flow from the holding device side to the master cylinder side,
By maintaining this state until the brake operation is released and the pressure of the front wheel braking device falls below a predetermined value from the holding device side (rear wheel side), the back torque application ratio on the front wheel side is reduced during this period. I tried to increase it on the rear wheel side, so that the switch was turned on, and this was maintained thereafter.

However, in order to turn on the switch stably,
Providing the valve device as described above causes a high cost because the structure of the valve device itself is considerably complicated and the piping of the pressure transmission system is complicated due to the intervention of the valve device. was there.

[Problems to be solved by the invention]

The present invention has been made in view of the above problems, and an object of the present invention is to provide a brake control device capable of reliably holding a brake with a simple configuration.

[Means for solving problems]

The above-mentioned object is to provide a second detection device for detecting the operation from the start time to the release time in the above configuration, and to continue the holding while one of the detection device and the second detection device detects the operation. This is achieved by the brake control device.

[Action]

Car suddenly brakes uphill and nose dive
Even if the direction of action of the brake frictional force on the rear wheels repeatedly changes due to repeated rocking back and the detection output of the first detection device fluctuates, the second detection device releases and closes from the start of the driver's operation. The braking force is maintained as long as it is detected up to.

〔Example〕

First, before explaining the embodiments of the present invention, the operating principle as the background of the present invention will be described with reference to FIG.

In FIG. 1, it is assumed that the automobile is traveling on a slope S in the direction of arrow F. Therefore, the wheel (1) is rotating in the direction of arrow A. As is well known, a wheel cylinder (2) is fixed to a back plate (3) fixed to the vehicle body side, and upper ends of a pair of bow-shaped shoes (4a) (4b) are pivotally attached to the wheel cylinder (2). . Further, the lower end portion is in contact with both end portions (6a) (6b) of the sliding anchor (6). The sliding anchor (6) can be freely inserted into the through hole of the anchor body (7) fixed to the back plate (3), and has both ends (6a) (6).
By contacting b) with the anchor body (7), the left and right forward movement positions and the left and right forward movement positions of the sliding anchor (6) are restricted. The left and right forward movement positions are shown in the figure. A switch actuating rod (8) is fixed to one end (6b), which abuts on an actuator (9a) of a switch (9) fixed to the anchor body (7). The actuator (9a) is biased to the left and right by a spring, not shown, and is off in the state shown. (10a) and (10b) are return springs that bias the shoes (4a) and (4b) inward. Also, shoe (4a) and bark plate (3)
A spring (10c) for tensioning the shoe (4a) in a direction in which the shoe (4a) is always in contact with one end (6a) of the sliding anchor (6) is stretched between the shoe and the shoe (4a) (4b). The switch (9) is prevented from malfunctioning due to backlash.

The brake configured as described above is called a so-called LT type drum brake, one shoe (4a) is called a leading shoe, and the other shoe (4b) is called a trailing shoe. Now, when a brake pedal (not shown) is depressed to stop the automobile, pressure fluid is supplied to the wheel cylinders (2), and the brake linings of the shoes (4a) (4b) rotate with the wheels (1) (5).
Is pressed against. A frictional force is generated between the shoes (4a) (4b) and the rotating body (5) in a direction opposite to the rotating direction of the rotating body (5) (direction of arrow A), and thereby a braking force is obtained. However, a reaction force of the same magnitude as the friction force but in the opposite direction acts as a brake reaction force as indicated by arrows B and C, and the leading shoe (4a) is pressed by the piston in the wheel cylinder (2). And reaction force B are added together and abut on one end (6a) of the sliding anchor (6), and the trailing shoe (4b) abuts on the other end (6b) by the difference. In addition, the leading side shoe (4a) is
It comes into stronger contact with the one end (6a). As a result, the force pushing the sliding anchor (6) to the right in the figure is larger, so that the sliding anchor (6) continues to assume the rightward reciprocating position shown, and the switch (9) remains off.

When the vehicle is stopped and the clutch is disengaged, the wheel (1) receives rotational force in the direction opposite to arrow A due to the action of gravity. That is, it receives back torque that tends to move the vehicle to the lowlands. The direction of the frictional force acting between the shoes (4a) (4b) and the rotating body (5) is reversed and becomes the direction of arrow B or C, but the magnitude of the frictional force on the trailing side shoe (4b) side. It becomes larger and the sliding anchor (6) slides to the left in the figure and takes a left-right reciprocating position. As a result, the actuator (9a) of the switch (9) is pressed and turned "on". The solenoid valve, which will be described later, is closed by this "on" signal, the master cylinder side and the wheel cylinder (2) side are cut off, and the brake is held even if the foot is released from the brake pedal. The clutch pedal may be kept away from the foot in the neutral position.

When the vehicle is started, when the clutch pedal is stepped into the half-clutch state and the accelerator pedal is stepped on, the driving torque is transmitted in the direction of arrow A to the wheel (1), that is, the rotating body (5). As a result, the frictional force between the shoes (4a) (4b) and the rotating body (5) is reversed again, and the brake reaction force shown by the arrows B and C acts on the shoes (4aa) (4b), and The dynamic anchor (6) moves to the right and assumes the right forward position shown. That is, the switch (9) is “off”.
The solenoid valve (not shown) is opened, and the master cylinder side and the wheel cylinder (2) side are in communication with each other. Thus, the hydraulic pressure in the wheel cylinder (2) is released to the master cylinder side, the brake is released, and the automobile starts.

Hereinafter, a brake control device according to an embodiment of the present invention will be described with reference to FIGS. 2 to 4. The parts corresponding to those in FIG. 1 are designated by the same reference numerals, and detailed description thereof will be omitted.

FIG. 2 shows the piping system. In the figure, the brake pedal (12) is connected to the tandem master cylinder (11),
The first hydraulic pressure generating chamber is connected to the front wheel (14a) via the pipe line (13).
It is connected to the wheel cylinder of (14b). Disc brakes are used for these front wheels (14a) (14b). The second hydraulic pressure generating chamber includes a pipe (15), a solenoid valve (18) and a pipe (1
It is connected to the wheel cylinders (2) of the rear wheels (20a) (20b) via 9). Drum brakes are adopted for these rear wheels (20a), (20b), and one rear wheel (20a) has the structure shown in FIG. 1 and is equipped with a switch (9). The other rear wheel (20b) is a normal drum brake.

The solenoid valve (18) is a two-position solenoid directional control valve. When the solenoid (28) is not energized, the spring (29) works to set the position D to connect the pipelines (15) and (19). However, when the solenoid (28) is energized, it takes the E position,
The conduits (15) and (19) are made non-conductive. A check valve (16) is connected in parallel with the solenoid valve (18).

FIG. 3 shows the brake control circuit including the switch (9) and the solenoid (28) of the solenoid valve (18). In the figure, the ignition switch (31) and the room lamp (44) are connected to the positive electrode of the battery (30). ) Is connected. The fixed contact side of the ignition switch (31) is connected to the gearback switch (32), the handbrake switch (33) and the normally closed contact (39) of the relay (36). Gear back switch (32) and hand brake switch (33)
Are switches that close when they are moved backward, and switches that close when you apply the handbrake. The fixed contact side of the gear back switch (32) has a back lamp (3
4) and via a diode (37) to a relay (36). The handbrake switch (33) is connected to the handbrake lamp (35) and to the relay (36) via the diode (38).

The normally closed contact (39) opens when the relay (36) is excited, and one fixed contact of the solenoid (28) of the solenoid valve (18), the pilot lamp (40) and the relay (41) has a fixed contact. The brake switch (42) is connected to the parallel connection circuit, which further serves as a second detection device of the present invention.
And tilt switch (43) in series circuit, and the rear wheel (20
It is connected to a parallel connection circuit with a switch (9) (hereinafter also referred to as a torque detection switch) provided in a). One fixed contact of the normally closed contact (39) is further connected to the connection point between the room lamp (44) and the door switch (45) via the contact (46), the buzzer (47) and the diode (48). Connected.

The contact (46) is a switch that is closed when the relay (41) is excited, and the brake switch (42) is a switch that is closed when the brake pedal (12) is depressed.

The tilt detection switch (43) has the structure shown in FIG. 4, but a tilt space (71) is formed in the switch body (74), and a magnet roll (72) is rotatably arranged therein. ing. The inclination angle α of the bottom surface of the sloping void (71) with respect to the horizontal line H-H is set to about 2 degrees, and when the vehicle is traveling on the road surface which is horizontal or nearly horizontal, the magnetic roll (72 ) Is in contact with the lower inner wall surface of the inclined space (71).

In the switch body (74), there is also a reed switch (73).
Is embedded and is open in the state shown in the figure, but when the car is traveling on an uphill road, the magnet roll (72)
Is configured to roll so as to come into contact with the upper inner wall surface of the inclined space (71) and close the reed switch (73).

The left side is the forward direction of the vehicle as shown by arrow F in FIG.

Further, the door switch (45) is a switch that closes when the door is opened, and FIG. 3 shows a state when the door is closed.

The embodiment of the present invention is configured as described above. Next, the operation, effect and the like will be described.

Now assume that the car is climbing a hill and has stepped on the brake pedal (12) to stop. The ignition switch (31) is already closed. As the car is climbing a slope, the magnet roll (72) rolls to the right in FIG. 4 and closes the reed switch (73). That is, the tilt switch (43) is closed in FIG. Further, the brake switch (42) is closed by depressing the brake pedal (12). Since the gearback switch (32) and the handbrake switch (33) are open as shown in the figure, the relay (36) is not energized and therefore its normally closed contact (39) remains closed. Current flows from the battery (30) to the ignition switch (31) → normally closed contact (39) → solenoid (28) → brake switch (42) → tilt switch (43), and the solenoid (28).
Is excited. In FIG. 2, the solenoid valve (18) is in the E position. On the other hand, a current also flows through the pilot lamp (40) and the relay (41) in parallel with the solenoid (28), the pilot lamp (40) lights up, and the solenoid valve (18) is in the shut-off state, that is, the braking force. Informs the driver that can be held. When the relay (41) is excited, the contact (4
Although 6) is closed, the door switch (45) is off because the door is closed, and the buzzer (47) and the room lamp (44) are not energized and remain inactive.

The pressure liquid from the master cylinder (11) is supplied to the wheel cylinders of the front wheels (14a) (14b) through the pipe line (13), and the pipe line (15), the check valve (16) (the solenoid valve (18 ) Solenoid (28) is energized to position E), conduit (1
It is supplied to the wheel cylinders (2) of the rear wheels (20a) (20b) through 9).

All wheels (14a) (14b) (20a) (20b) are braked and the vehicle slows down. In the rear wheel (20a), the shoes (4a) and (4b) are pressed against a rotating body (which is rotating in the direction of arrow R) not shown, and a frictional force is generated between them,
Leading shoe (4a) as described in Fig. 1.
The brake reaction force acting on the sliding force is greater than the sliding anchor (6).
Is the right forward position shown in the figure. That is,
Since the torque detection switch (9) remains off, the current for exciting the solenoid (28) of the solenoid valve (18) flows exclusively through the brake switch (42) and the tilt detection switch (43).

When the car stops on a slope, the rotating body that was rotating with the wheels generates turning force in the opposite direction when the vehicle is running,
The frictional force acting between the rotating body and the shoes (4a) (4b) is reversed. As a result, the brake reaction force to the shoe (4b) on the trailing side becomes larger, and the sliding anchor (6) is pushed to the left to take the left forward movement position.
The switch actuating rod (8) pushes the actuator (9a) of the switch (9). The switch (9) is turned on.
When the driver releases the pedal force on the brake pedal (12) in this state, brake fluid flows back from the front wheel (14a) (14b) wheel cylinders to the master cylinder (11), but the solenoid valve (18) is shut off. Since it is in a state, rear wheels (20a) (20b)
The brake fluid does not flow back from the wheel cylinder (2), and the pressure fluid is retained there. This allows the car to remain stationary on the slope. Conventionally, the clutch pedal must be kept depressed to maintain the braking force, but in the present embodiment, the foot can be kept away from the pedal.

Since the pilot lamp (40) continues to light up, the driver can recognize that the solenoid valve (28) is operating and the braking force is maintained.

However, it is conceivable that the driver may ignore this or forget to leave the driver's seat and leave the vehicle without applying the parking brake. In this embodiment, in such a case, the buzzer (47) sounds to warn the driver. That is, the handbrake switch (33) remains open, and when the door is opened, the door switch (45) is closed and the buzzer (47) is energized. When the parking brake is applied, the handbrake switch (33) is closed and the contact (39) is opened.
7) does not ring.

When the vehicle is started, the gears are switched and the clutch pedal is in the half-clutch state, and the accelerator pedal is depressed, the driving force is transmitted to the rotating body (not shown) of the rear wheel (20a), and the rotating body and the shoe (4a) ( The frictional force with 4b) is reversed again, the braking reaction force to the shoe (4a) on the leading side becomes larger, the sliding anchor (6) is pushed to the right, and the position shown in the figure is reached. To take. Switch (9) is off,
Since the brake switch (42) is also off, the solenoid valve (18) is de-energized. The solenoid valve (18) takes the D position again and is communicated with the wheel cylinder (2) side of the master cylinder (11) side. The pressure liquid held in the wheel cylinder (2) flows back to the master cylinder (11) through the electromagnetic valve (18) in the illustrated state. Thus the brakes are released and the car starts.

After stopping on a slope, you may want to move backward. In this case, when the gear is switched to move backward, the gear back switch (32) is closed and the relay (36) is excited. This causes its contact (39) to contact the solenoid (2
The energization to 8) is cut off, the solenoid valve (18) is set to the D position, and the pressure liquid in the wheel cylinders (2) of the rear wheels (20a) (20b) flows back to the master cylinder (11) side. Therefore, the car can move backward freely.

The normal case where the car stops on a slope has been described above. However, depending on the slope angle of the slope and the suspension mechanism of the car body, when the sudden braking is applied, the switch (9) of the rear wheel (20a) turns on. In some cases, it may not be maintained.

That is, in the above-described case, when the brake is suddenly applied, a so-called nose dive phenomenon occurs in the vehicle, and the rear wheel side of the vehicle body is in a posture of floating from the ground. After that, it sank by rocking back, and nose dive by rocking again. On the first nose dive, switch (9) remains off, but it turns on when the swingback sinks.
However, the switch (9) is turned off at the next nose dive. The switch (9) does not turn on stably when the car is stopped. Since the back torque of the front wheels almost always keeps the vehicle stopped, if the brake pedal (12) is released in this state, the vehicle would move backward and it was dangerous. This embodiment can deal with such a situation.

That is, when the pedal force on the brake pedal (12) is released after sudden braking, the pressure liquid in the wheel cylinders of the front wheels (14a) (14b) immediately returns to the master cylinder (11) through the pipe line (13). Begin to. However, the rear wheels (20
a) The hydraulic fluid in the wheel cylinder (2) of (20) is
It does not flow back to the master cylinder (11) as soon as a) (14b). The brake switch (42) remains closed until the brake pedal returns from the depressed position to the initial position. Therefore, during this period, regardless of whether the torque detection switch (9) is closed or open, the solenoid (2
8) continues to be excited. That is, the rear wheels (20a) (20b)
The hydraulic fluid is retained in the wheel cylinder (2) of the.

When the brake pedal (12) returns to the initial position, the brake switch (42) opens. However, during this time, the front wheels (14
The hydraulic fluid from the wheel cylinders of (a) and (14b) is sufficiently returned to the master cylinder (11), the ratio of the back torque applied to the front wheels is sufficiently small, and the back torque of the rear wheels is smaller. It is getting bigger. Therefore, the switch (9) maintains the ON state before the brake pedal (12) returns to the initial position. After the brake pedal (12) returns to the initial position, the direct current from the battery (30) flows exclusively through the torque switch (9) side, so that the solenoid (28) is excited. Therefore, since the solenoid valve (18) is in the closed state, the brake fluid is retained from the wheel cylinders (2) of the rear wheels (20a) (20b) without the pressure fluid returning to the master cylinder (11) side. To be done. The vehicle is started in the same manner as described above.

Although the embodiments of the present invention have been described above, needless to say, the present invention is not limited to these, and various modifications can be made based on the technical idea of the present invention.

For example, although the sliding anchor (6) is used in the embodiment, it is used as a fixed anchor and a strain gauge is attached to it.
The switch may be opened / closed by this output.
Further, although the change in the direction of the frictional force in the drum brake has been described above, the change in the direction of the frictional force in the pad in the disc brake may be detected.

Further, various circuit configurations are possible without being limited to the circuit (FIG. 3) described in the above embodiments. For example, in the above embodiment, the brake switch (42) and the inclination detection switch (43) are connected in series, and the torque switch (9) is connected in parallel to this series circuit. The tilt detection switch (43) may be connected in series to a parallel circuit of the torque switch (9) and the parallel switch 42). This prevents the solenoid (28) from being excited even if the vehicle is running on a flat ground and is suddenly braked and turned on for some reason. Further, in the above-mentioned embodiment, the accelerator switch which is turned off when the pedal is further stepped on the torque detection switch (9) and is turned on when it is not stepped on may be connected in parallel.

Further, in the above embodiment, the buzzer (47) sounds when the door is opened without applying the handbrake while holding the braking force on the uphill road, and the buzzer (47) sounds when the door is opened with the handbrake. 47) does not ring. However, at this time the normally closed contact (39)
Is opened to de-energize the solenoid (28) and the pressure fluid is circulated from the wheel cylinder to the master cylinder (11). That is, although the vehicle is braked only by the hand brake, the hydraulic fluid may still be held in the wheel cylinders even if the hand brake is applied depending on the circuit configuration.

〔The invention's effect〕

As described above, according to the brake control device of the present invention, instead of holding / releasing the brake by the clutch disengagement / connection operation by the driver, the turning force generated in the rear wheel itself is generated when the vehicle is stopped on an uphill road and moved forward. Paying attention to the fact that it is in the opposite direction to the time, the brake is held / released by detecting the change in the direction of action of the brake friction force corresponding to this, so that after the vehicle is stopped until the vehicle starts, The brake holding state can be maintained regardless of human operation. Then, at the time of starting, the brake held when the turning force in the forward direction is generated on the rear wheels is released,
Since the braking force does not decrease before the driving force required for starting to be transmitted to the wheels, it is possible to reliably prevent the vehicle from slipping backward when starting on an uphill road.

In addition to this, a second detection device that detects the braking operation by the driver from the start to the release is provided, and the brake holding state is continued as long as the detection is made. Immediately after the vehicle suddenly stops at, for example, even if the action direction of the brake frictional force on the rear wheels changes due to a change in the suspension and the detection device for this changes and switches, the turning force (back torque) in the backward direction is applied to the rear wheels. The brake will not be released before it continues to operate. Therefore,
It is possible to reliably prevent the vehicle from moving backward due to the release of the brake operation after the vehicle is stopped.

[Brief description of drawings]

FIG. 1 is a schematic side view of a wheel on a slope for explaining an operating principle which is a background of the present invention, FIG. 2 is a piping system diagram of a brake control device according to an embodiment of the present invention, and FIG. 3 is the same. A circuit diagram of the electric circuit of the control device and FIG. 4 are cross-sectional views of a specific configuration of the tilt detection switch in FIG. In the figure, (9) …… torque detection switch (18) …… solenoid valve (28) …… solenoid (42) …… brake switch

Claims (1)

(57) [Claims] 1. A detection device for detecting an action of a rotational force of a rear wheel in a backward direction by a change in an action direction of a brake frictional force on the rear wheel, and a braking force generated on the wheel according to an operation of a driver. In a brake control device comprising a holding device capable of holding the operation of the brake device based on the detection of the detection device despite the release of the operation,
A brake control device which is provided with a second detection device that detects the operation from the start to the release and continues the holding while one of the detection device and the second detection device detects the operation.