JPH0516244B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a brake abnormality monitoring device used in electric vehicles and the like, which accurately detects a lack of regular braking force.

[Prior Art] FIG. 2 is a partial block diagram of a conventional brake abnormality monitoring device and its peripheral circuitry.

In the figure, 1 indicates abnormality detection command 1 during braking.
This is a brake controller that outputs a brake command 1b and a brake command 1b. Normally, the brake command 1b has a command amount of 7 steps from the initial stage of braking to the completion of braking, and the abnormality detection command 1a has a command amount of 6 steps from the initial stage of braking to the completion of braking.
The signal is set to "H" only at the step. 2 is an on-timer connected to the brake controller 1, and when an abnormality detection command 1a is input, it outputs a signal 2a with a time delay. 3 is a brake relay connected to on-timer 2, and output 2a of on-timer 2
The b contact 3a is opened.

Reference numeral 4 denotes a brake abnormality monitoring device to which a 100V DC power signal Vd, a 100V DC power signal Vb via the b contact 3a, and a normally-excited 100V DC emergency brake power signal Ve are input. Reference numeral 5 denotes an electric brake control device having a chopper device, etc., which operates in response to a brake command 1b, and controls a motor current 5a proportional to the electric brake force by a brake force pattern corresponding to a brake step to a current relay (not shown). ) is output to the brake abnormality monitoring device 4 via the contact point 9. 6 is an air brake control device, which, like the electric brake control device 5, outputs a cylinder pressure 6a proportional to the air brake force to the brake abnormality monitoring device 4 in a pattern corresponding to the steps of the brake command 1b. ing.

7 is an abnormality detection relay that opens each A contact 7a, 7b when demagnetized, and has a diode _D1 at one end.
A power signal Vb is applied through the terminal, and the other end is grounded. 8 is a CR circuit connected between both ends of the abnormality detection relay 7 and consisting of a resistor R and a capacitor C, and each a contact 7a, 7 of the abnormality detection relay 7
This is to provide a time delay in opening b. Reference numeral 9 denotes a current relay contact that closes when a current exceeding a predetermined value is detected, and one end is connected to the electric brake control device 5, and the other end is connected to one end of the abnormality detection relay 7 via a diode _D2 . . 1
0 is a barometric pressure switch that is activated by the cylinder pressure 6a and closes when pressure above a predetermined value is detected;
A power signal Vd is applied to one end, and the other end is connected to one end of the abnormality detection relay 7 via an a contact 7b. 40 is a device output terminal, to which an emergency brake power signal Ve is applied via the a contact 7a of the abnormality detection relay 7.

11 is an emergency solenoid valve that opens a valve (not shown) and operates an emergency brake (not shown) when demagnetized; one end is connected to the device output terminal 40;
The other end is grounded.

Next, the operation of the conventional device shown in FIG. 2 will be explained.

During normal power running, the abnormality detection command 1a and the brake command 1b are not output, so the electric brake control device 5 and the air brake control device 6
is not activated, so both current relay contacts 9 and pneumatic switch 10 are open. Also, since the brake relay 3 is not excited and its b contact 3a is closed, the power signal is not transmitted through this b contact 3a.
The abnormality detection relay 7 is excited by Vb and closes each a contact 7a, 7b. Therefore, the emergency brake power signal Ve is output from the device output terminal 40, and the emergency solenoid valve 11 is energized, so that the emergency brake is not activated.

During braking, the electric brake control device 5 and the air brake control device 6 are activated by the brake command 1b.
are motor current 5a and cylinder pressure 6, respectively.
a is output to the brake abnormality monitoring device 4. When the brake command 1b reaches the sixth step, the on-timer 2 excites the brake relay 3 with a predetermined time delay in response to the abnormality detection command 1a, and opens the b contact 3a. Therefore, the power signal Vb is cut off from the abnormality detection relay 7. However, if the service brake is normal, the motor current 5a and the cylinder pressure 6a are
has risen sufficiently, current relay contact 9
and the barometric switch 10 are closed, and the motor current 5a via the current relay contact 9 and the barometric switch 1
Abnormality detection relay 7 by power signal Vd via 0
continues to be excited. In this way, when the service brake is normal (FIG. 2 shows this state), the a contact 7a continues to be closed, so the emergency solenoid valve 11 remains energized, and therefore the emergency brake does not operate.

An abnormality occurs in the service brake, and the cylinder pressure 6a of the air brake control device 6 does not rise normally, and the motor current 5a of the electric brake control device 5
If the current does not exceed a predetermined value, the current relay contact 9 and the air pressure switch 10 are opened, so at the same time as the b contact 3a is opened by the abnormality detection command 1a,
The abnormality detection relay 7 is demagnetized by cutting off all inputs, and the a-contacts 7a and 7b are opened after a predetermined time delay by the CR circuit 8. Therefore, the emergency brake command E is output from the device output terminal 40, in other words, the emergency brake power signal Ve is no longer output, so the emergency solenoid valve 11 is demagnetized. As a result, the emergency brake is activated, making it possible to back up the lack of regular braking force.

Incidentally, even if the cylinder pressure 6a increases due to the activation of the emergency brake and the air pressure switch 10 is closed, the a contact 7b is already open.
Unless the abnormality detection command 1a is canceled and the b contact 3a is closed, the abnormality detection relay 7 will not be energized again. Therefore, until the abnormality detection command 1a is canceled, the a contact 7a remains open and the emergency brake continues to operate.

Also, the reason why the non-applying (cutting off) signal of the emergency brake power signal Ve output from the device output terminal 40 is set as the emergency brake command E is because the abnormality detection relay 7 and each power signal Ve, Vb, and Vd have expired. When,
This is to provide a fail-safe effect so that the emergency solenoid valve 11 is demagnetized and the emergency brake is activated.

[Problems to be Solved by the Invention] Since the conventional brake abnormality monitoring device is configured as described above, the motor current 5a of the electric brake control device 5 and the cylinder pressure 6a of the air brake control device 6 are separately controlled. Moreover, the detection level is fixed, that is, point detection, so the detection accuracy is poor. Furthermore, the detection level must be set when the braking force is at its minimum, for example, according to the empty car load condition, so even if the required braking force is large, such as when the car is full, even if the actual service braking force is insufficient. However, there was a problem in that brake abnormalities could not be detected.

This invention was made to solve the above-mentioned problems, and detects brake abnormalities based on the total braking force, which is the addition of electric braking force and air braking force. An object of the present invention is to obtain a brake abnormality monitoring device that can accurately detect abnormalities in a service brake by changing its detection level.

[Means for Solving the Problems] A brake abnormality monitoring device according to the present invention includes a comprehensive brake signal generation circuit including an operational amplifier, a brake calculator, an abnormality command circuit including a comparator, and an emergency brake command generation circuit. The operational amplifier inputs a signal corresponding to electric brake force and a signal corresponding to air brake force, outputs a total brake signal by adding the two, and performs brake calculation. The device inputs a brake command and a load signal and outputs a necessary brake signal according to these brake commands and load signals,
The comparator inputs the total brake signal and the required brake signal, and when the deviation between these signals exceeds a predetermined value, outputs a brake abnormality signal indicating that the regular braking force from the electric brake and air brake is insufficient. The abnormality command circuit outputs an abnormality command based on the abnormality detection command and the brake abnormality signal, and the emergency brake command generation circuit is driven in response to the abnormality command and outputs an emergency brake command to operate the emergency brake. It is something that makes you

[Function] In this invention, when a brake command is issued, that is, when a brake command is input, the operational amplifier in the general brake signal generation circuit detects the total brake force of the service brake, and the brake calculator calculates the brake command step and load. A comparator in the abnormality command circuit compares the total brake force with the required brake force, and outputs a brake abnormality signal when the deviation exceeds a predetermined value. As a result, the abnormality command circuit generates an abnormality command based on the abnormality detection command and the brake abnormality signal, and in response to this abnormality command, the emergency brake command generation circuit outputs an emergency brake command and operates the emergency brake. .

[Example] Hereinafter, an example of the present invention will be described with reference to the drawings. FIG. 1 is a partial block diagram of a brake abnormality monitoring device and its peripheral circuitry according to the present invention. In the figure, 1-3, 5-7, 9, 1
1 and 40 are the same conventional devices as described above,
4A is a brake abnormality monitoring device similar to 4.

20 is a pneumatic converter that converts the cylinder pressure 6a into an air control signal 20a, and 21 is a pneumatic converter that converts the air spring pressure P proportional to the vehicle load into a load signal 21a. Reference numeral 22 denotes an operational amplifier, into which a signal corresponding to the electric brake force, that is, a motor current 5a, and an air control signal 20a corresponding to the air brake force are input, and outputs a total brake signal 22a. 23 is a brake calculator having a ROM table, etc., to which the brake command 1b and load signal 21a are input, and outputs the necessary brake signal to obtain a predetermined deceleration according to the brake step and load. There is. Although not shown, the brake calculator 23 receives information from the electric brake control device 5 and the air brake control device 6.
A brake force pattern signal corresponding to a brake step may be input, and a necessary brake signal 23a corresponding to each brake force pattern may be output.

24 is a comparator to which the total brake signal 22a and the required brake signal 23a are input, and when the deviation between the two signals exceeds a predetermined value, the output 24a becomes a brake abnormality signal, that is, "H". A second contact 7b, which is the a contact of the abnormality detection relay 7, is connected in series between the comparator 24 and the operational amplifier 22, and a receiving relay 25, which will be described later, is connected in parallel with the second contact 7b.
A second contact 25b, which is an a contact, is connected. 25 is a receiving relay to which the power signal Vb is applied to one end and the other end is grounded; during braking, it is demagnetized and closes the first contact 25a, which is the B contact, and the second contact 25b, which is the A contact. Third contact 2
5c is now open. Receiving relay 2
A power signal is always connected to one end of the first contact 25a of 5.
Vd is applied, and the third contact 25c is connected in parallel with the first contact 7a of the abnormality detection relay 7. 26 is a power signal via the b contact 25a
This is a NAND element into which Vd and the output 24a of the comparator 24 are input. 27 is the output 2 of the NAND element 26
It is a transistor with a grounded emitter and whose base input is 6a, and whose collector is connected to one end of the abnormality detection relay 7. A power signal Vd is always applied to the other end of the abnormality detection relay 7. The operational amplifier 22, the second contact 7b of the abnormality detection relay 7, and the second contact 25b of the reception relay 25 constitute a comprehensive brake signal generation circuit X that outputs a comprehensive brake signal 22a. The operational amplifier 22 inputs the motor current 5a corresponding to the electric brake force and the air control signal 20a corresponding to the air brake force.
A total brake signal 22a obtained by adding the two is output, and the signal is output to the comparator 2 via each second contact 7b and 25b.
Enter 4.

The comparator 24, the NAND element 26, the abnormality detection relay 7, and the transistor 27 constitute an abnormality command circuit Y that outputs the abnormality command YE. Comparator 24
inputs the total brake signal 22a and the required brake signal 23a, and when the deviation between these signals exceeds a predetermined value, generates a brake abnormality signal 24a indicating that the regular braking force by the electric brake and the air brake is insufficient. Output. Receiving relay 25
The power signal Vd via the b contact 25a is inputted to the NAND element 26 as an abnormality detection signal e.
The abnormality detection relay 7 is demagnetized via the transistor 27 which is turned off by the output signal 26a of the NAND element based on the abnormality detection signal e and the brake abnormality signal 24a. First contact 7a from abnormality detection relay 7
The release signal for this becomes the abnormality command YE.

The third contact 25c of the reception relay 25 and the first contact 7a of the abnormality detection relay 7 constitute an emergency brake command generation circuit Z that generates an emergency brake command E in response to the abnormality command YE. activates the emergency brake.

Next, the operation of one embodiment of the present invention will be explained.

During normal power running, both the abnormality detection command 1a and the brake command 1b are not output, so
B contact 3a of brake relay 3 is closed,
The receiving relay 25 is in an energized state. Therefore, the second contact 25b and the third contact 25c are closed,
Since the first contact 25a is open, the first contact 25a cuts off the power signal Vd, and the NAND element 26
``L'' is input to one end of . Therefore, the output 26a of the NAND element 26 becomes "H", the transistor 27 is turned on, and the abnormality detection relay 7 is energized, so the first contact 7a of the abnormality detection relay 7 is closed together with the second contact 7b. . Therefore, the emergency brake power signal Ve is applied to the device output terminal 40, and the emergency solenoid valve 11 is energized, so that the emergency brake does not operate.

During braking, the electric brake control device 5 and the air brake control device 6 are activated by the brake command 1b.
is activated, and outputs signals corresponding to the respective braking forces, that is, motor current 5a and air control signal 20a, to the brake abnormality monitoring device 4A. The operational amplifier 22 adds the motor current 5a and the air control signal 20a and outputs a total brake signal 22a proportional to the total brake force. Also, based on the brake command 1b and the load signal 21a, the brake calculator 23 generates a necessary brake signal 23a according to the command amount of the brake command 1b, that is, the step, and the load at the time of the brake command.
Output.

The comparator 24 compares the total brake signal 22a and the required brake signal 23a, and if the deviation exceeds a predetermined value, it determines that the regular brake force is insufficient (brake abnormality) and sets the output 24a to "H".
to output a brake abnormal signal. The predetermined value of the comparator 24 is determined based on the performance of the brake system, etc., and is set to prevent malfunction. Normally, the service brake is normal, so set it to "L".
The output 24a of is input to one end of the NAND element 26.

On the other hand, the receiving relay 25 is demagnetized by opening the b contact 3a based on the abnormality detection command 1a, and the first
Switch the contact 25a to closed. Therefore, the power signal
Vd is applied to the other end of the NAND element 26 as an abnormality detection signal e. At the same time, the second contact 25b and the third contact 25c are switched to open, but since the first contact 7a and the second contact 7b of the abnormality detection relay 7 continue to be closed, the general brake signal 22a and the emergency brake signal are Comparator 2 of the power signal Ve, respectively
4. The application state to the device output terminal 40 remains unchanged. Note that the demagnetizing operation of the reception relay 25 has a time delay from the output timing of the brake command 1b as described above, so the contacts 25a to 25c do not switch until the service brake is fully activated.

When the service brake force is normal (FIG. 1 shows this state), the output 24a of the comparator 24 is "L", so the NAND element output 26a becomes "H", and the first Since the contact point 7a continues to be closed, the emergency brake power signal Ve output from the device output terminal 40 continues to excite the emergency solenoid valve 11, so that the emergency brake is not activated.

When the comparator 24 detects an abnormality in the service brake force, its output 24a becomes "H", that is, a brake abnormality signal, and the output 26a of the NAND element 26 becomes "L".
becomes. Then, since the transistor 27 is turned off and the abnormality detection relay 7 is demagnetized, both the first contact 7a and the second contact 7b are opened, and the total brake signal 2 is output from the operational amplifier 22 to the comparator 24.
At the same time as the input of 2a is cut off, the device output terminal 4
Emergency brake power signal from 0 to emergency solenoid valve
The application of Ve is cut off. Therefore, the device output terminal 4
0 is due to no application signal, that is, emergency brake command E,
The emergency solenoid valve 11 is demagnetized and the emergency brake is activated. Even if the cylinder pressure 6a increases after the emergency brake is activated, the contacts 25b and 7b are already open and the comprehensive brake signal 22a from the operational amplifier 22 is not input to the comparator 24, so the abnormality detection command 1a is not canceled. The emergency brake will continue to operate as long as possible.

When the abnormality detection command 1a is released, the first contact 25a of the receiving relay 25 is opened, and the second contact 25
b and the third contact 25c are closed. Then, the output 26a of the NAND element 26 becomes "H" and the emergency brake is released.

According to the present invention, the output 26a of the NAND element 26 is used to normally drive the abnormality detection relay 7, so even if the power signal Vd expires, the emergency brake is activated and a fail-safe function can be achieved as before. . Also, if there is no abnormality detection command 1a,
By closing the third contact 25c of the receiving relay 25,
This prevents unnecessary operation of the emergency brake.

[Effects of the Invention] As described above, according to the present invention, there is provided a brake having a comprehensive brake signal generation circuit including an operational amplifier, a brake calculator, an abnormality command circuit including a comparator, and an emergency brake command generation circuit. In the abnormality monitoring device, an operational amplifier inputs a signal corresponding to electric brake force and a signal corresponding to air brake force, and outputs a total brake signal by adding the two. The comparator inputs the command and load signal and outputs the required brake signal according to these brake commands and load signals. , a brake abnormality signal indicating that the regular braking force from the electric brake and air brake is insufficient is output, and the abnormality command circuit outputs an abnormality command based on the abnormality detection command and the brake abnormality signal, and The brake command generation circuit is driven in response to the abnormality command and outputs an emergency brake command to activate the emergency brake, thereby making the total braking force of the service brake the subject of brake abnormality detection, and also detecting the load and brake command. Since the brake abnormality detection level is changed in accordance with the required braking force that differs depending on the step, there is an effect that a brake abnormality monitoring device with high brake abnormality detection accuracy can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram partially showing a brake abnormality monitoring device and its peripheral circuit according to an embodiment of the present invention, and FIG. 2 is a partial block diagram showing a conventional brake abnormality monitoring device and its peripheral circuit. It is a circuit diagram. 1a... Abnormality detection command, 1b... Brake command, 4
A... Brake abnormality monitoring device, 5... Electric brake control device, 5a... Motor current, 6... Air brake control device, 7... Abnormality detection relay, 7a... First contact,
7b...Second contact, 11...Emergency solenoid valve, 20a...Air control signal, 21a...Load signal, 22...Operation amplifier,
22a... General brake signal, 23... Brake calculator, 23a... Necessary brake signal, 24... Comparator,
24a...Brake abnormal signal, 25...Receiving relay,
25a...first contact, 25b...second contact, 25c...
3rd contact, 26...NAND element, 40...device output terminal, E...emergency brake command, Vd, Vb...power signal, Ve...power signal for emergency brake, e...abnormality detection signal, YE...abnormality command, X...general Brake signal generation circuit, Y...Abnormal command circuit, Z...Emergency brake command generation circuit. In each figure, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Scope of Claims] 1. Brake abnormality monitoring device having a comprehensive brake signal generation circuit X including an operational amplifier 22, an abnormality command circuit Y including a brake calculator 23, a comparator 24, and an emergency brake command generation circuit Z The operational amplifier 22 outputs a signal 5a corresponding to the electric brake force and a signal 20 corresponding to the air brake force.
The brake calculator 23 inputs the brake command 1b and the load signal 21a, and outputs the total brake signal 22a by adding the two together. The comparator 24 outputs the brake signal 23a, and inputs the total brake signal 22a and the required brake signal 23a, and when the deviation between these signals exceeds a predetermined value, the comparator 24 determines that the regular braking force by the electric brake and the air brake is insufficient. The abnormality command circuit Y outputs the abnormality command YE based on the abnormality detection command 1a and the brake abnormality signal 24a, and the emergency brake command generation circuit Z outputs the abnormality command YE.
It is driven in response to the emergency brake command E and outputs the emergency brake command E to operate the emergency brake. Brake abnormality monitoring device. 2. The abnormality command circuit Y outputs an abnormality command YE in response to the first contact 25a of the receiving relay 25, a NAND element 26 that inputs the brake abnormality signal 24a and the abnormality detection signal e, and the output signal 26a of the NAND element 26.
The receiving relay 25 is deenergized in response to the abnormality detection command 1a, and the first contact 25a is closed when the receiving relay 25 is deenergized to output the abnormality detection signal. The brake abnormality monitoring device according to claim 1, wherein the emergency brake command generation circuit Z has a first contact 7a that is closed by an abnormality command YE from the abnormality detection relay 7. 3 The comprehensive brake signal generation circuit
The brake according to claim 1 or 2, comprising a contact 7b and a second contact 25b that is connected in parallel to the second contact 7b of the abnormality detection relay 7 and is opened when the receiving relay 25 is deenergized. Abnormality monitoring device. 4 Emergency brake generation circuit Z is the receiving relay 25
It has a third contact 25c that is opened when the power is de-energized, and the third contact 25c is connected in parallel to the first contact 7a of the abnormality detection relay 7. Brake abnormality monitoring device as described.