JPH0436900B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an automatic parking brake system for a vehicle.

[Prior art]

Conventionally, in this type of automatic parking brake system, for example, as disclosed in Japanese Utility Model Application Publication No. 59-42749, an electromagnetic actuator is used to control a ratchet engaged with a rotatably supported ratchet wheel. There is a parking brake device that is disengaged from the ratchet wheel to release the braking action on the vehicle.

[Problem to be solved by the invention]

However, in such a configuration, if the above-mentioned ratchet wheel and ratchet are tightly engaged, it is impossible to dissociate the ratchet from the ratchet wheel using the electromagnetic actuator. This was one of the factors that made it impossible to release the braking action on the vehicle.

Therefore, in order to cope with this problem, the present invention attempts to facilitate the dissociation between the ratchet wheel and the ratchet lever that constitute the ratchet mechanism when releasing the brake in an automatic parking brake system for a vehicle. It is something to do.

[Means to solve the problem]

In order to solve the above problems, the present invention includes a parking brake mechanism that brakes a vehicle when placed in a braking operating state and releases the brake when placed in a releasing operating state; a ratchet wheel that puts the parking brake mechanism in the braking operating state in response to rotation in one rotational direction and puts the parking brake mechanism in the releasing operating state in response to rotation in the other rotational direction; and an outer periphery of the ratchet wheel. The ratchet wheel is pivotally supported in a suitable position on the vehicle in the vicinity of the surface thereof, and in response to rocking in the engagement direction along the one rotational direction, the tip engages with the outer circumferential surface of the ratchet wheel in the other rotational direction. a ratchet mechanism consisting of a ratchet lever that disengages from the outer circumferential surface of the ratchet wheel at its tip in response to rocking in a disengagement direction along A starting operation detection means 1 that generates a starting operation detection signal, a brake release detection means 2 that detects when the braking state of the vehicle is released and generates a brake release detection signal, and responds to the starting operation detection signal. rotational direction output signal generating means 3 which temporarily generates one rotational direction output signal, generates another rotational direction output signal, and eliminates the other rotational direction output signal in response to the brake release output signal; , a dissociation direction output signal generating means 4 for generating a dissociation direction output signal in response to the start operation detection signal, and extinguishing the dissociation direction output signal in response to the brake release output signal.
and driving the ratchet wheel to rotate in the one rotation direction while the same signal is being generated in response to the one rotation direction output signal, and generating the same signal in response to the other rotation direction output signal. a rotary drive means 5 for driving the ratchet wheel to rotate in the other rotational direction while the ratchet lever is being rotated in the other rotational direction; The present invention further includes a swing drive means 6 that drives the ratchet lever to swing in the engagement direction in response to disappearance of the release direction output signal.

[Operations and Effects of the Invention] By configuring the present invention as described above, when the starting operation mechanism is operated under braking operation in the braking operation state of the parking brake mechanism for the vehicle, the rotational direction output signal generating means 3 temporarily generates a one-rotation direction output signal in response to a start operation detection signal from the start operation detection means 1, and at the same time, the dissociation direction output signal generating means 4 generates a dissociation direction output signal. Then, the rotary drive means 5 responds to the one-rotation direction output signal and drives the ratchet wheel to temporarily rotate in the one-rotation direction while the same signal is generated, and the swing drive means 6 drives the ratchet lever to swing in the dissociation direction in response to the dissociation direction output signal. Therefore, the temporary rotation of the ratchet wheel in the one-rotation direction and the rocking of the ratchet lever in the disassembly direction are realized almost simultaneously in the same direction, so that the ratchet lever can Even if the ratchet lever is tightly engaged with the outer peripheral surface of the ratchet wheel, the ratchet lever can be easily and timely disengaged from the ratchet wheel.

Thereafter, when the rotational direction output signal generating means 3 generates another rotational direction output signal, the rotation driving means 5 drives the ratchet wheel to rotate in the other rotational direction. Therefore, when the ratchet lever is disengaged from the ratchet wheel as described above, the ratchet wheel rotates in the other rotational direction to place the parking brake mechanism in the release operating state. Therefore, the brakes on the vehicle can be released with good responsiveness.

Then, when the brake release detection means 2 generates a brake release detection signal in response to this brake release, the rotation direction output signal generation means 3 eliminates the other rotation direction output signal, and at the same time, the dissociation direction output signal generation means 4
causes the dissociation direction output signal to disappear. Therefore, the rotation drive means 5 stops the rotation of the ratchet wheel in the other rotational direction, and
A swing drive means 6 swings the ratchet lever in the engagement direction. Therefore, the end portion of the ratchet lever reliably engages with the outer peripheral surface of the ratchet wheel. As a result, the brake release state of the parking brake mechanism on the vehicle can be properly maintained through the ratchet wheel.

〔Example〕

Hereinafter, one embodiment of the present invention will be described with reference to the drawings. FIG. 2 shows an example in which the present invention is applied to an automatic parking brake system for a vehicle equipped with an automatic transmission (not shown). This automatic parking brake system includes a parking brake mechanism 10, an electric mechanism 20 that drives this parking brake mechanism 10, and this electric mechanism 2.
0. The parking brake mechanism 10 has a parking lever 11, which is pivotally supported on a floor surface near a console box in the passenger compartment of the vehicle so as to be tiltable in the vertical direction by a horizontal shaft 11a. There is.

A pulley 1 is provided at the base end of the parking lever 11.
2 is pivotally supported by a horizontal shaft 11a so as to integrally interlock with the parking lever 11. On the other hand, a cylindrical handle 13 is fixed to the tip of the parking lever 11. The handle 13 is a knob 13
a, and this knob 13a has a handle 1
The release lever (not shown), which is rotatably attached to the parking lever 11, is pushed against the coil spring (not shown) (provided in the hollow part of the handle 13) in the hollow part of the handle 13. Engagement part of bracket fixed to surface (not shown)
Dissociate from. When the knob 13a is opened, the coil spring urges the knob 13a outward, causing the release lever to engage with the engaging portion of the bracket, thereby keeping the parking lever 11 unrotatable.

The cable 14a is wound around the outer circumference of the pulley 12, and one end of the cable 14a is connected to a bolt 12b fitted into the metal fitting 12a of the pulley 12.
The other end of the cable 14a is loosely fitted into a long hole 15a (see FIG. 3) provided in the center of the equalizer 15.
Therefore, the cable 14a is connected to the second pulley 12.
Equalizer 1 according to the clockwise rotation shown in the figure.
5 to the left in FIG.
The equalizer 15 is rotated in the counterclockwise direction shown in the figure.
Allow to move to the right. Equalizer 15 is
Its both ends are connected to the respective brake shoes of both rear wheels Wl, Wr of the vehicle through respective rear cables 16a, 16b, and its leftward movement pulls both rear cables 16a, 16b to the left, while its The right movement allows both rear cables 16a, 16b to move to the right. The rear wheels Wl, Wr are braked by the respective brake shoes in response to the leftward pulling force of both rear cables 16a, 16b, and the leftward pulling force of both rear cables 16a, 16b disappears. The braking is released by each brake shoe. Further, in FIG. 2, reference numeral 12c indicates a nut for adjusting the position of the bolt 12b.

The electric mechanism 20 includes a rotary electric motor 21 and a reduction gear 2
2, pulley 23, and linear actuator 24
It is equipped with As shown in FIGS. 2, 4, and 5, the reducer 22 has a bearing (not shown) mounted on a support shaft 22a fixed within its casing.
It has a worm wheel 22b rotatably supported by a worm wheel 22b.
A worm 22c driven by a rotary electric motor 21 is engaged with b. In such a case, the worm wheel 22b and the worm 22c rotate normally (or reversely) in accordance with the normally (or reversely) rotation of the rotary electric motor 21.

The worm wheel 22b includes a ratchet wheel 22d that constitutes a ratchet mechanism together with a ratchet lever 22e.
The ratchet wheel 2 is provided integrally with the worm wheel 22b and coaxially with the worm wheel 22b.
2d, a one-way clutch 22f is coaxially connected to the ratchet wheel 22d and becomes engaged (or disengaged) when the ratchet wheel 22d rotates forward (or reversely). It's getting old. In such a case, the engaged state (or disengaged state) of the one-way clutch 22f is
This is achieved by engaging (or disengaging) each clutch member integrally formed with the pulley 2d and the pulley 23, respectively. The ratchet lever 22e is swingably supported within the casing by a support shaft 22g so that its pawl portion selectively engages with the toothed portion of the ratchet wheel 22d. is engaged with the L-shaped plunger 24a of the linear actuator 24. This means that the linear actuator 24
When the solenoid is de-energized, plunger 2
4a in its original position, and then turn the ratchet lever 22e.
and the ratchet wheel 22d,
This means that the energization of the solenoid attracts the plunger 24a and disengages the ratchet lever 22e from the ratchet wheel 22d.

The pulley 23 is rotatably supported by the outer end of the support shaft 22a from which the casing extends through a bush 23a press-fitted into its center hole, and is connected to the ratchet wheel 22d through a one-way clutch 22f. has been done. A link rod 22h is provided on the lower surface of the pulley 23, and the link rod 22h is connected to the knob 13a of the parking lever 13 via a cable 14c. As the knob 13a is pushed, the link rod 22h is pulled upward by the cable 14c and moves upward, causing the pulley 23 to move upward along the support shaft 22a and disengaging the one-way clutch 22f. On the other hand, in response to the opening of the knob 13a, the link rod 22h moves downward under the action of a spring (not shown), allowing the one-way clutch 22f to engage as the pulley 23 moves downward.

A cable 14 extending from the equalizer 15 in the same direction as the cable 14a is provided on the outer periphery of the pulley 23.
b is wound and connected to a part of the pulley 23 at its outer end. Therefore, the pulley 23 winds the cable 14b and pulls the equalizer 15 to the left in FIG. 2 by rotating in the normal direction when the one-way clutch 22f is engaged, and by rotating in the reverse direction when the one-way clutch 22f is disengaged, the pulley 23 twists the cable 14b. Rewinding allows the equalizer 15 to move to the right. In addition,
The one-way clutch 22f partially protrudes from the upper wall of the casing so as to be movable up and down. The cable 14b also has an equalizer 15 at its inner end.
It is loosely fitted into a long hole 15b (see FIG. 3) formed in the center of the hole.

The electric control circuit 30 includes a shift switch 31,
An accelerator switch 34, a release switch 33,
It has a vehicle speed sensor 34, a rotational speed sensor 35, an ignition switch SW and a DC power supply B of the vehicle, and a microcomputer 36 connected to each switch 31, 32, 33 and each sensor 34, 35, Ignition switch SW
generates a first (or second) closing signal by applying the movable contact to the ignition fixed contact IG (or starter fixed contact ST).

The shift switch 31 closes and generates a shift signal in response to a shift operation of the automatic transmission to a drive range or a reverse range, and generates a shift signal in response to a shift operation of the automatic transmission to a neutral range or a parking range. is opened to eliminate the shift signal. The accelerator switch 32 closes in response to depression of the accelerator pedal of the vehicle and generates a depression signal, and opens in response to release of the accelerator pedal to eliminate the depression signal. The release switch 33 is closed to generate a release signal when the braking by the electric mechanism 20 is released, and is opened to eliminate the release signal when a braking force is generated based on the operation of the electric mechanism 20. In addition, each switch 31~
33 is a permanently open type. Further, in FIG. 2, the symbol M indicates the starter motor of the vehicle.

Vehicle speed sensor 34 detects the vehicle speed of the vehicle and generates a series of vehicle speed pulses having a frequency proportional to this. A rotational speed sensor 35 detects the rotational speed N of the internal combustion engine of the vehicle and generates a series of rotational speed pulses having a frequency proportional to this. The microcomputer 36 is always in operation by being supplied with power from the DC power supply B, and executes a computer program stored in advance in accordance with the flowchart shown in FIG. As described above, various calculation processes necessary for controlling the rotary electric motor 21, the linear actuator 24, and the pilot lamp L are performed. Pilot lamp L is on (or off)
The execution status (or non-execution status) of the computer program by the microcomputer 36 is displayed.

In this embodiment configured as described above, the ratchet lever 22e when the vehicle is stopped
When the movable contact of the ignition switch SW is sequentially connected to the ignition fixed contact IG and the starter fixed contact ST while engaged with the ratchet wheel 22d, the microcomputer 36 connects the first contact from the ignition switch SW. In response to the closing signal, the computer program starts executing at step 40 according to the flowchart shown in FIG. 6, and at step 41, it is repeatedly determined as "YES" based on the second closing signal from the ignition switch SW. .
Then, the internal combustion engine is started under the drive of the starter motor M, and the second
When the closing signal disappears, the determination at step 41 becomes "NO". At this time, it is assumed that the one-way clutch 22f is in an engaged state.

Therefore, when the rotational speed N of the internal combustion engine determined by each rotational speed pulse from the rotational speed sensor 35 is larger than the predetermined rotational speed No, the microcomputer 36 determines "YES" in step 42,
At step 42a, a lighting signal necessary for lighting the pilot lamp L is generated. Then, the pilot lamp L lights up in response to the lighting signal from the microcomputer 36. Thereby, the driver can visually recognize that the microcomputer 36 has started executing the computer program. The above-described predetermined rotational speed No. is stored in advance in the microcomputer 36 as a value (for example, 400 rpm) that is greater than or equal to the cranking rotational speed of the internal combustion engine and less than or equal to the idling rotational speed.

Next, the microcomputer 36 generates an excitation signal necessary to excite the solenoid of the linear actuator 24 in step 42b, and
At 42c, a normal rotation signal necessary for normal rotation of the rotary motor 21 is generated for t seconds (for example, 1 second). Then, the solenoid of the linear actuator 24 is excited in response to the excitation signal from the microcomputer 36 and attracts the plunger 24a, and the rotary motor 21 is activated by the microcomputer 36.
It rotates in the normal direction in response to the normal rotation signal from the motor. In other words, when the ratchet lever 22e is pulled by the plunger 24a of the linear actuator 24 to separate from the ratchet wheel 22d, as shown by the broken line in FIG. Since the wheel 22b rotates slightly in the normal direction in response to the normal rotation of the rotating electric motor 21, the ratchet lever 22e
Even if the engagement between the pawl of the ratchet lever 22d and the bar of the ratchet wheel 22d is in a firm state, the ratchet lever 2
2e can be easily and timely separated from the ratchet wheel 22d.

Thereafter, during the cyclic calculation of both steps 43 and 44, if the automatic transmission is shifted to the drive range or reverse range and the accelerator pedal is depressed, the microcomputer 3
6 determines "YES" in step 43 based on the depression signal generated from the accelerator switch 32,
The switch 45 determines "YES" based on the shift signal generated from the shift switch 31, and the switch 45a generates a reversal signal necessary to reverse the rotating electric motor 21.

Then, during the cyclic calculation of both steps 46 and 45a, the rotating electric motor 21 is controlled by the microcomputer 3.
It reverses in response to the reversal signal from worm 2.
2c, the worm wheel 22b and the ratchet wheel 22d are reversed, and the pulley 23 is moved under the engagement of the one-way clutch 22f and the ratchet lever 22e.
The cables 14a, 14b and the equalizer 1 are reversed when released from the ratchet wheel 22d.
5 and both rear cables 16a and 16b are moved to the right by the elastic action of the coil springs of the two brake shoes to release the braking action on both rear wheels Wl and Wr. Next, when a release signal is generated from the release switch 33, the microcomputer 36 determines "YES" in step 46, and each step 46a,
At 46b, the reversal signal and the excitation signal are sequentially extinguished. Therefore, the rotating electric motor 21 stops when the reversal signal from the microcomputer 36 disappears, stopping the speed reducer 22 and the pulley 23, and the linear actuator 24 operates as a solenoid in response to the disappearance of the excitation signal from the microcomputer 36. When demagnetizing the ratchet lever 22e, the plunger 24a moves the ratchet lever 22e to the ratchet wheel 22.
d as shown by the solid line in FIG. As a result, the vehicle can be started while the electric mechanism 20 is released and held for braking under the engagement of the ratchet mechanism.

However, after such a start, both steps 47 and
48, if the level of the vehicle speed pulse from the vehicle speed sensor 34 changes for more than a predetermined time (for example, the change time of the level of the vehicle speed pulse at a vehicle speed of 1 km/h or less is 1 second) as the vehicle shifts to a stop. When it is gone, the microcomputer 36 determines "YES" in step 48, and proceeds to step 42b.
An excitation signal is generated at step 42c, and a normal rotation signal is generated for t seconds at step 42c. Then, the linear actuator 24 is activated by the plunger 24a under the excitation of the solenoid responsive to the excitation signal from the microcomputer 36.
At the same time, the rotary electric motor 21 rotates in the normal direction in response to a normal rotation signal from the microcomputer 36, causing the worm 22c, the worm wheel 22b, and the latchet wheel 22d to rotate in the normal direction. Under the engagement of the one-way clutch 22f, the pulley 23 is rotated in the normal direction, and the equalizer 15 and both rear cables 16a, 16b are pulled to the left by the cable 14b, and both rear wheels Wl,
Put Wr in braking state. Then, after the normal rotation signal from the microcomputer 36 disappears, the step
43, the first closing signal is extinguished from the ignition switch SW, and the microcomputer 36
44, a normal rotation signal is generated for t seconds in step 47a, and in step 47b, the power supply to each element of the electric control circuit 30 is cut off, and the execution of the computer program is stopped. This means that unnecessary power consumption in the electrical control circuit 30 can be reduced. In addition, in response to the power supply interruption described above, the pilot lamp L goes out and the linear actuator 24
When the solenoid is demagnetized, the plunger 24
By a, the ratchet lever 22e is engaged with the ratchet wheel 22d, and the rotating electric motor 21 is stopped. At this time, under the engagement of the ratchet mechanism, the reducer 22 rotates the pulley 2 based on its reduction ratio.
Since reversal from the third side is disabled, the braking force for the vehicle is maintained as is. In this embodiment, the ignition switch SW, shift switch 31, and accelerator switch 32 correspond to the start operation detection means 1, the release switch 33 corresponds to the brake release detection means 2, and the microcomputer 36
correspond to the rotation direction output signal generation means 3 and the dissociation direction output signal generation means 4, the rotary electric motor 21 corresponds to the rotation drive means 5, and the linear actuator 24 corresponds to the swing drive means 6.

In addition, when manually releasing the braking action of the electric mechanism 20, by pushing the knob 13a of the parking lever 11, the link rod 22h is pulled by the cable 14c and operates upward. Accordingly, the pulley 23 supports the support shaft 22a.
The one-way clutch 22f is disengaged. Next, when the parking lever 11 is tilted downward, the pulley 23 is reversed and the braking action of the electric mechanism 20 is released in the same manner as described above.

Further, in the above embodiment, an example in which the present invention is applied to the parking brake mechanism 10 having the parking lever 11 has been described, but the present invention is not limited to this, and the present invention can be applied to, for example, a pedal-type or stick-type parking brake mechanism. It may also be carried out.

Further, in carrying out the present invention, step 45
After determining "YES", an excitation signal is generated and a normal rotation signal is generated for t1 seconds (for example, 0.1 to 0.2 seconds) to excite the solenoid of the linear actuator 24 and rotate the rotary motor 21 for t1 seconds. Achieves substantially the same effect as described above under normal rotation,
The calculation in step 45a may be performed after that. Note that if you select "YES" in step 44,
After the determination, the excitation signal is made to disappear.

Further, in the embodiment, the rotary electric motor 21 is used as the drive source, but instead of this, a positive or negative pneumatic pressure source, a hydraulic pressure source, or the like may be used as the drive source.

[Brief explanation of drawings]

FIG. 1 is a diagram corresponding to the configuration of the claimed invention, FIG. 2 is an overall configuration diagram showing an embodiment of the present invention, and FIG. 3 is a plan view of the equalizer of the parking brake mechanism shown in FIG. 2. , FIGS. 4 and 5 are perspective views of essential parts showing the inside of the electric mechanism shown in FIG. 2, and FIG. 6 is a flowchart showing the operation of the microcomputer shown in FIG. 2. Explanation of symbols, 10... Parking brake mechanism, 20... Electric mechanism, 21... Rotating electric motor, 2
2...Reduction gear, 22d...Ratchet wheel,
22e... Ratchet lever, 24... Linear actuator, 36... Microcomputer.

Claims (1)

[Scope of Claims] 1. A parking brake mechanism that brakes a vehicle in a braking state and releases the brake in a releasing state; a ratchet wheel that puts the parking brake mechanism in the braking operating state in accordance with the rotation of the vehicle and puts the parking brake mechanism in the releasing operating state in response to rotation in the other rotational direction; The ratchet wheel is pivotally supported in a suitable position so that it can swing, and when the ratchet wheel swings in the engagement direction along the one rotational direction, the tip engages the outer circumferential surface of the ratchet wheel and moves in the dissociation direction along the other rotational direction. a ratchet mechanism consisting of a ratchet lever that dissociates from the outer circumferential surface of the ratchet wheel at its tip in response to the rocking of the ratchet; and a starting operation that detects when the starting operating mechanism of the vehicle is operated and generates a starting operation detection signal. a detection means; a brake release detection means for detecting when the braking state of the vehicle is released and generating a brake release detection signal; and a brake release detection means for temporarily generating a one rotation direction output signal in response to the starting operation detection signal. a rotational direction output signal generating means for generating another rotational direction output signal and extinguishing the other rotational direction output signal in response to the braking release output signal; and a dissociation direction output signal in response to the starting operation detection signal. dissociation direction output signal generating means for generating a dissociation direction output signal and extinguishing the dissociation direction output signal in response to the braking release output signal; Rotation driving means for driving the wheel to rotate in the one rotational direction and driving the ratchet wheel to rotate in the other rotational direction while the other rotational direction output signal is being generated in response to the other rotational direction output signal. and, in response to generation of the dissociation direction output signal, the ratchet lever is driven to swing in the dissociation direction, and in response to disappearance of the dissociation direction output signal, the ratchet lever is driven to swing in the engagement direction. An automatic parking brake system for a vehicle, comprising a swing drive means that drives the vehicle.