JPH0241101Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a brake fluid pressure control device used in a hydraulic brake device of an automobile.

[Technical Background and Problems] As a conventional brake fluid pressure control device, there is, for example, one disclosed in Japanese Patent Application Laid-open No. 103648/1983. In this type of brake fluid pressure control device, a load sensor detects the load on the vehicle, and the control means outputs a command signal to the motor according to the detected load value, and the load sensing proportioning valve (LSPV)
The set load of the spring was adjusted.

However, in the brake fluid pressure control device configured as described above, the control system for controlling the pressure reduction start point of the LSPV calculates the pressure reduction start point of the LSPV based on the detection signal from the load sensor, It was a so-called open loop control system that outputs output to the motor. Therefore, the command signal output from the control means is affected by radio noise from outside the vehicle, static electricity generated inside the vehicle, etc., and there is an error between the command signal from the control means and the rotational drive amount of the motor actually driven. Not only will this error occur, but the error will also accumulate.
There was a problem that the control of the LSPV's depressurization start point was not compatible with the vehicle.

[Purpose] Therefore, the present invention is intended to improve the above-mentioned problems of the conventional technology, and its purpose is to eliminate the problem even if there is radio noise from outside the vehicle or static electricity generated inside the vehicle.
An object of the present invention is to provide a brake fluid pressure control device that can always adapt control of a pressure reduction start point of an LSPV to a vehicle.

[Configuration] The fourth feature of the present invention to achieve the above purpose is
As shown in the figure, a master cylinder 201 that generates hydraulic pressure in response to brake pedal force, a wheel cylinder 205 that operates by the hydraulic pressure generated in this master cylinder 201, and a space between the master cylinder 201 and the wheel cylinder 205. a control valve 203 that is interposed in the control valve 203 to reduce the outlet hydraulic pressure in response to the inlet hydraulic pressure, a control valve adjustment means 207 that adjusts the pressure reduction start point of the control valve 203, and a load detection means that detects the vehicle load. 211 and this load detection means 2
The control valve adjusting means 20 adjusts the pressure reduction start point of the control valve 203 to the target pressure reduction start point according to the detected load of the control valve 11.
control means 20 that performs a certain amount of drive control for 7;
9, a detection means 215 for detecting the drive position of the control valve adjustment means 207, and a correction means 213 for replacing the control amount with a control amount determined by the control means 209 in accordance with the actual control amount. Located in the control device.

[Operation] In the above configuration, the control means outputs an output to the control valve adjusting means so that the pressure reduction start point of the control valve becomes the target pressure reduction start point based on the load detection value output from the load detection means. The control valve adjusting means starts to be driven by the output from the control means. On the other hand, when the detection means detects that the control valve adjustment means has been driven and moved to the installation position of the means, it outputs an output to the correction means, and the correction means is set in advance in accordance with the installation position of the detection means. Compare the drive control amount of the control valve adjusting means and the actual control amount by the control means, and if it is recognized that a difference has occurred between the two, the output value from the control means is adjusted to the preset control valve adjustment amount. This will be replaced by the drive control amount of the means. Therefore, even if the signal output from the control means to the control valve adjustment means is affected by radio noise from outside the vehicle, static electricity generated inside the vehicle, etc., the drive control amount of the control valve adjustment means by the signal will not change. Since the correction means replaces the actual control amount with a control amount determined corresponding to the actual control amount, it is possible to improve the control of the pressure reduction start point of the control valve.

[Example] Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic diagram of a brake fluid pressure control device according to an embodiment of the present invention, FIG. 2 is a diagram showing a hydraulic pressure control actuator of the brake fluid pressure control device according to an embodiment of the present invention, and FIG. A flowchart of the configuration of FIG. 1 is shown.

In FIG. 1, a master cylinder 5 is connected to a brake pedal 1 via a booster 3.

The master cylinder 5 has a first hydraulic chamber 7 and a second hydraulic chamber 9.
It is constructed such that equal hydraulic pressure is generated in both chambers 7 and 9 via the booster 3 as the brake pedal 1 is operated. Said first hydraulic chamber 7
are connected to the front wheel cylinders 11 and 13 of the front disc brake of the front wheel brake,
The second hydraulic chamber 9 is connected to rear wheel cylinders 15 and 17 of a rear drum brake, respectively, via a hydraulic pressure control actuator 19.

The hydraulic control actuator 19 is constructed as shown in detail in FIG. 2, and includes a control valve 21, a detection means, ie, a micro switch 50, and a control valve adjustment means, ie, a pulse motor 25. . The control valve 21 is provided between the inlet port 29 and the outlet port 31 of the actuator main body 27, and is configured to reduce the outlet hydraulic pressure in response to the inlet hydraulic pressure. That is, the control valve 21 has a plunger 23 whose large diameter portion is slidably fitted into a valve chamber 33 having an inner diameter cross-sectional area _A1 , and a valve seat 35 is integrally formed on one end side of the plunger 23. When installed, the valve seat 35 is brought into contact with the actuator main body 27, and a first chamber 37 is defined.

The smaller diameter portion of the other end of the plunger 23 is slidably supported by a valve holder 39 having an inner diameter cross-sectional area A ₂ , and a second chamber 41 communicating with the inlet port 29 is provided between the valve holder 39 and the plunger 23 . Further, the end side of the small diameter portion is provided with a spring storage chamber 4 formed in the actuator main body 27.
3 is on the way. A valve body housing chamber 45 is formed in the plunger 23, and a poppet valve body 47 is housed within the valve body housing chamber 45. A first spring 49 is interposed between the poppet valve body 47 and the plunger 23, and the poppet valve body 47 is brought into contact with the actuator body 27. In the state shown in FIG. 2 in which both the valve seat 35 and the poppet valve body 47 are in contact with the actuator body 27 in this way, the poppet valve body 47 is in an open state away from the valve seat 35. The valve body storage chamber 45 is communicated with the first chamber 37 through a first through hole 51 and with the second chamber 41 through a second through hole 53 .

A spring receiving portion 55 is fitted into a portion of the small diameter portion on the other end side of the plunger 23 facing the spring storage chamber 43, and the other end of the spring receiving portion 55 is fitted with a flange portion 58 of the spring receiving member 57.
One end of the second spring 59, which is engaged with the second spring 59, is received. The flange 58 side of the spring receiving member 57 is connected via a ball 61 to a bolt 63 whose outer periphery is formed with a male thread. The inner peripheral surface of the bolt 63 and the rotating shaft 65 of the pulse motor 25 are prevented from rotating by a key 66, and the bolt 63 receives the rotational force of the pulse motor 25 and converts it into a stroke. It is configured such that the force is transmitted to the spring receiving portion 55. The spring receiving member 57 is slightly moved by the pulse motor 25 and the bolt 63 described above to adjust the elastic force of the second spring 59.

As shown in the figure, a plurality of micro-switches 50 are provided in the spring storage chamber 43 at predetermined intervals, and each of the micro-switches 50 has an operating member 52 attached to the spring storage chamber 43 so as to be freely retractable. . Each of the above-mentioned actuating members 52 has an end portion connected to a spring storage chamber 43 as shown in the figure.
By contacting the collar portion 58 which is moved by the rotational force of the pulse motor 25 while in contact with the inner wall surface of the micro switch 50, the contacts of the respective micro switches 50 are closed and a predetermined signal is output. It is composed of The micro switch 50 is connected to the input side of the control unit 67 via a signal line, and a position detection signal of the flange 58 is output from the micro switch 50 to the control unit 67 via the signal line. be.

The pulse motor 25 is connected to the output side of a control unit 67 shown in FIG. 1 via a signal line, and a drive command signal is sent to the pulse motor 25 from the output side of the control unit 67 via the signal line. Output.

One end of the shock absorber 69 is the shock absorber 69.
1, and the other end is fixed to the central axle 7.
3 and is locked at both ends to a leaf spring 75 supported by the chassis 71. The shock absorber 69 is provided with a load sensor 77 that detects the relative displacement between the sprung and unsprung parts of the vehicle and converts it into a load, and is connected to the input side of the control unit 67 via a signal line. ing. The brake pedal 1 is provided with a brake operation sensor 79 for detecting whether the brake pedal 1 is operated or not, and is connected to the input side of the control unit 67 via a signal line.

The control unit 67 is composed of an electronic circuit control device such as a microcomputer, and includes an arithmetic control section such as a CPU, a ROM,
It consists of a storage section such as RAM. The arithmetic control section performs arithmetic and logical operations and comparison operations. The arithmetic control section finally takes in the detection signal output from the load sensor 77 when the detection signal is not output from the brake operation sensor 79, determines the pressure reduction start point, and calculates the number of output pulses to obtain a stroke corresponding to the pressure reduction start point. The pulses are read from the storage section and outputted to the pulse motor 25 via the signal line by the number of pulses. When the arithmetic control unit recognizes that a predetermined signal has been output from the micro switch 50 provided at a position corresponding to the preset length of the second spring 59, it stops the output to the pulse motor 25, and , reads out from the storage section the count value of the pulses that have been output so far and the count value data of the number of output pulses that is preset corresponding to the set length of the second spring 59 at the installation position of the micro switch 50. compare. When recognizing that there is a difference between the two as a result of the comparison, the arithmetic control section resets the count value of the number of output pulses in the internal counter immediately before stopping the output to the pulse motor 25, and also sets the count value in the internal counter. Set numerical data.

The storage unit contains control programs and the like, and also stores necessary data. The data stored in the storage unit includes, for example, the count value data calculation control of the number of output pulses that is preset corresponding to the set length of the second spring 59 at the set value position of each microswitch 50 as described above. There is data regarding the appropriate split point calculated by the department.

The operation of the above structure will be explained below mainly with reference to the flowchart of FIG.

When a passenger such as a driver operates a switch to start supplying power to the control unit 67 from a drive power source (not shown), the control unit 67
starts driving. The arithmetic control unit determines whether or not a detection signal is being output from the brake operation sensor 77 (step 101), and if it recognizes that it is not being output, it sequentially captures the load detection value output from the load sensor 77 (step 103). ). After calculating the appropriate split point corresponding to the detected load value taken in step 103 (step 105), the calculation control section calculates the stroke (or the first spring 49) determined from the calculated appropriate split point. , the set load on the second spring 59) is output to the pulse motor 25 to drive the pulse motor 25 by a desired step (step 107). Step 1
After outputting a command to the pulse motor 25 in step 07, it is determined whether a detection signal is output from any of the microswitches 50 (step 1).
09) When it is recognized that the pulse has been output, the pulse output to the pulse motor 25 is stopped and the drive of the pulse motor 25 is stopped (step 111).

After the pulse output is stopped in step 111, the arithmetic control section outputs the output set in accordance with the counted value of the number of output pulses when the detection signal is output from the micro switch 50 and the installation position of the micro switch 50. The count data of the number of pulses is compared, and when it is determined that the two do not match (step 113), the count value is reset and the count data stored in the storage section is set in an internal counter (step 113). Step 1
15). In order to obtain the set length of the second spring 59 corresponding to the appropriate split point determined in step 107, the arithmetic control section uses the count value data of the number of output pulses set in the internal counter in step 115 as a reference value, and compares this with the reference value. A drive command signal is output to the pulse motor 25 by the difference between the output pulse count and the count value calculated in step 107 (step 117).

Note that when the counted value of the number of output pulses from the arithmetic control section matches the preset number of output pulses in step 113, step 115,
Of course, the operation of step 117 is not performed.

As explained above, according to an embodiment according to the present invention, at least one micro switch 50 is arranged at arbitrary intervals so as to face the spring storage chamber 43 in the hydraulic control actuator 27, so that it can be easily accessed from the calculation control section. The output pulse signal is affected by disturbance, and there is a difference between the set length set by driving the pulse motor 25 by this pulse signal and the desired set length calculated in step 107. Even if this occurs, the count value data of the number of output pulses preset at the installation location of each micro switch 50 is set instead of the count value data of the number of output pulses.
Errors can be reduced. Furthermore, since it is possible to use a DC motor with an extremely slow rotational speed in place of the pulse motor, it is also possible to reduce the cost of the hydraulic control actuator.

It should be noted that the above-mentioned contents are only related to one embodiment according to the present invention, and it goes without saying that the present invention is not limited to only the above-mentioned contents.

[Effects] As explained above, according to the present invention, the detection means for detecting the drive position of the control valve adjustment means and the correction means for replacing the actual control amount with a predetermined control amount corresponding to the control amount by the control means are provided. By providing this, it is possible to provide a brake fluid pressure control device that can improve the control of the pressure reduction start point of the control valve even if there is radio noise from outside the vehicle or static electricity generated inside the vehicle.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of a brake fluid pressure control device according to an embodiment of the present invention, FIG. 2 is a diagram showing a hydraulic pressure control actuator of the brake fluid pressure control device according to an embodiment of the present invention, and FIG. FIG. 1 is a diagram showing a flowchart of the configuration, and FIG. 4 is a diagram corresponding to claims. 5...Master cylinder, 11, 13...Front wheel cylinder of front disc brake, 1
5, 17... Rear wheel cylinder of rear drum brake, 19... Hydraulic pressure control actuator, 21...
Control valve, 25...Pulse motor, 50
...Micro switch, 52... Operating member, 67... Control unit, 77... Load sensor.

Claims (1)

[Scope of utility model registration request] A master cylinder that generates hydraulic pressure in response to brake pedal force; a wheel cylinder that operates using the hydraulic pressure generated by the master cylinder; A control valve that controls the pressure reduction, an adjustment means that adjusts the pressure reduction start point of the control valve by changing the set load position of a spring, a load detection means that detects the load of the vehicle, and a detection means for the load detection means. a control means for controlling the drive of the adjustment means by a certain amount so that the pressure reduction start point of the control valve becomes a target pressure reduction start point according to the loaded load; and a predetermined position on the drive path of the adjustment means. at least one detecting device installed in the position and detecting and outputting that the adjusting means is driven and passes through the position.
The fixed amount of drive of the adjustment means is compared with the drive control amount determined corresponding to the installation position of the detection means based on the output of this detection means, and if the two are different, the fixed amount of the former is used. A brake fluid pressure control device comprising a correction means that replaces and corrects the latter control amount.