JPH0147341B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a vehicular brake device that issues a brake command as an electric signal and applies the brake using fluid at a pressure corresponding to this signal.

BACKGROUND OF THE INVENTION Conventionally, there is a brake device of this type as shown in FIG. 1, and the conventional device will be described below with reference to FIG.

The lead-in line 10 is the first vehicle 11 and the second vehicle
12. It is wired sequentially to the third and subsequent vehicles (not shown), and is connected to the output terminal of the command device 1 in the leading vehicle 11. The command device 1 is the brake handle 1
a and a cam switch (not shown), and is configured to issue a brake command consisting of a 3-bit digital signal to the lead-in line 10 by operating the brake handle 1a. Each vehicle is provided with a receiver 2 and an electro-pneumatic conversion valve 3, the input end of the receiver 2 is connected to the lead-in line 10, and the output end is connected to the solenoid of the electro-pneumatic conversion valve 3. 3
connected to a. The receiver 2 is connected to the lead-in line 10
The electro-pneumatic conversion valve 3 is configured to include a D-A conversion circuit and an amplifier circuit (not shown) for converting a digital signal from the digital signal into an analog signal, and to transmit a brake command consisting of an analog signal to the electro-pneumatic conversion valve 3. 3
is configured to send air at a pressure corresponding to an input brake command to a brake cylinder (not shown). Incidentally, the reference numeral 5 in FIG. 1 is a power supply line for the receiver.

This conventional device had the following problems.

(a) Since all cars in the train set are equipped with receivers, maintenance and inspection of the receivers is not only complicated, but also heavy and expensive.

(b) Each vehicle requires a power source for the receiver;
A power line for a receiver must be connected to a vehicle that does not have a power source, which increases the number of lead-through lines and complicates the wiring. Since the lead-through lines are usually connected via couplers between vehicles, if the number of lead-through lines increases, the couplers may have to be replaced.

(c) Since each vehicle is equipped with a receiver and the wiring is complicated due to the large number of lead-in lines, these receivers and lead-in lines consume a large amount of energy.

The present invention was devised in view of the above-mentioned problem, and a receiver that amplifies and outputs the electrical signal is installed only in the leading vehicle equipped with a command device that issues a brake command using an electrical signal. An electro-pneumatic conversion valve that sends fluid at a pressure according to the electrical signal from the meter is installed in each vehicle, and the solenoids of these electro-pneumatic conversion valves are connected in parallel to the lead-in line from the meter. By further providing the receiver with a compensation circuit that changes the output of the receiver in accordance with temperature changes so as to maintain a constant current flowing through the solenoid of the electro-pneumatic conversion valve, the vehicle, in particular, The aim is to reduce the weight of vehicle brake systems, simplify rigging, facilitate maintenance and inspection, and save energy.

The following description will be made based on the embodiments of the present invention shown in FIGS. 2 and 3.

A command device 1 and a receiver 6 are installed in the leading vehicle 11, and the output end of the command device 1 is connected to the input end of the receiver 6. The command device 1 includes a brake handle 1a and a cam switch (not shown), and is configured to transmit a brake command consisting of a 3-bit digital signal to the receiver 6 by operating the brake handle 1a. It is something.
The lead-in line 20 connected to the output end of the receiver 6 is wired to each vehicle, and the electro-pneumatic conversion valve 3 is installed in each vehicle, and the solenoids of the electro-pneumatic conversion valve 3 are pulled in parallel with each other. It is connected to the through wire 20. The receiver 6, as shown in FIG. 3, converts the digital signal from the command unit 1 into an analog signal.
It consists of an A conversion circuit 6a, a compensation circuit 6b whose resistance changes with temperature changes, and an amplifier circuit 6c that amplifies the analog signal. The compensation circuit 6b includes resistors R1,
R2 is connected in series, and a thermistor RT having a negative temperature coefficient is connected in parallel to the resistor R1,
Solenoid 3a of electropneumatic conversion valve 3 due to temperature change.
Even if the resistance value of the solenoid 3a changes, the current flowing through the solenoid 3a is kept constant. That is, this is to maintain the fluid pressure delivered from the electro-pneumatic conversion valve 3 constant regardless of temperature changes in response to a brake command of the same level issued from the command unit 1.

Next, the operation of the above embodiment will be explained.

In the leading vehicle 11, when the brake handle 1a of the command device 1 is operated to the brake position, a brake command in the form of a digital signal corresponding to the brake position is transmitted to the receiver 6, and the receiver 6 receives the D-A signal.
A conversion circuit 6a converts the digital signal into an analog signal, this signal is input to an amplifier circuit 6c via a compensation circuit 6b, and the amplifier circuit 6c outputs an amplified analog signal. This analog signal is transmitted to the electro-pneumatic conversion valve 3 of each vehicle via the lead-in line 20, and the electro-pneumatic conversion valve 3 directly or indirectly supplies fluid at a pressure corresponding to the current flowing through the solenoid 3a to the brake cylinder (not shown). ). In this way, the brake cylinder is activated and brakes are applied to each vehicle.

When the ambient temperature changes due to changes in weather conditions, for example, when the ambient temperature rises, the resistance value of the solenoid 3a of the electro-pneumatic conversion valve 3 increases.

At this time, if the output voltage of the receiver 6 decreases or remains constant in response to the same brake command from the controller 1, the current flowing through the solenoid 3a decreases, and the voltage of the electro-pneumatic conversion valve 3 decreases. The delivery fluid pressure will decrease, and therefore, even though the same brake command is issued from the command unit 1, the braking force acting on the vehicle will decrease.

However, in the embodiment of the present invention, the problem of brake force fluctuations due to temperature changes as described above is solved by the action of the compensation circuit 6b of the receiver 6.

For example, when the ambient temperature decreases, the resistance value of the solenoid 3a of the electro-pneumatic conversion valve 3 decreases.At this time, the resistance value of the resistors R1 and R2 of the compensation circuit 6b also decreases, but on the other hand, the resistance value of the thermistor RT decreases. Since this thermistor RT has a larger absolute value of the temperature coefficient than the resistors R1 and R2, the combined resistance value as the compensation circuit 6b will eventually increase.
Therefore, the input voltage of the amplifier circuit 6c drops and the output voltage also drops. In this way, as the resistance value of the solenoid 3a decreases, the output voltage of the receiver 6 also decreases, so the current flowing through the solenoid 3a remains constant regardless of the decrease in ambient temperature. The braking force relative to the command is held constant.

When the brake handle 1a of the command device 1 is returned to the release position, the brake command is released and the brakes of each vehicle are released.

In the above embodiment, the command device 1 used is one that issues a brake command using a digital signal, but a command device that issues a brake command using an analog signal may also be used. −
The A conversion circuit 6a can be deleted.

Furthermore, in the above explanation, we have ignored the change in the resistance value of the lead-through line due to temperature change, but this is because it is very small compared to the change in the resistance value of the solenoid 3a of the electro-pneumatic conversion valve 3, so it cannot be ignored. In this case, a compensation circuit may be connected to each solenoid 3a, but this becomes more complicated than the above embodiment.

Furthermore, in the above description, although the configuration of the electropneumatic conversion valve 3 is not explained in detail, the valve may be any valve that delivers fluid at a pressure corresponding to the current flowing through the solenoid 3a. For example, an electro-pneumatic conversion valve with a built-in permanent magnet may be used to increase the gain, but since this electro-pneumatic conversion valve is easily affected by the ambient temperature,
The present invention is particularly effective for a brake device using such an electropneumatic conversion valve.

As is clear from the above description, the present invention provides for receiving a receiver that amplifies and outputs a brake command from a command device only to a leading vehicle equipped with a command device, and applying pressure according to the output of the receiver. An electro-pneumatic conversion valve that sends out fluid is installed in each vehicle, and the solenoid of this electro-pneumatic conversion valve is connected in parallel to the lead-in line from the receiver, and the electro-pneumatic converter is connected to the receiver in parallel. Since the present invention includes a compensation circuit that changes the output of the receiver according to temperature changes so as to maintain a constant current flowing through the solenoid of the conversion valve, the following effects can be obtained according to the present invention. .

(i) Each vehicle except the lead vehicle is not equipped with a receiver, which makes maintenance and inspection of the receiver easier, and makes it possible to reduce the weight and cost of the vehicle.

(ii) There is no need for a power source for the receiver of each vehicle except the first vehicle, and its power supply wires, and fewer lead-in lines are required, simplifying the wiring and other equipment, and at the same time, making maintenance and inspection easier. Furthermore, since fewer lead-through lines are required, the structure of the connecting portion (coupler) between each vehicle becomes simpler.

(iii) Since there are far fewer receivers and lead-through lines than in the past, energy consumption in these can be suppressed.

[Brief explanation of drawings]

Figure 1 is a schematic diagram of a conventional vehicle brake system.
FIG. 2 is a schematic diagram of an embodiment of a vehicle brake system according to the present invention, and FIG. 3 is a receiver 6 in FIG. 2.
FIG. 1... Command device, 3... Electro-pneumatic conversion valve, 3a... Solenoid, 6... Receiver, 6b... Compensation circuit, 2
0... Leading line.

Claims (1)

[Claims] 1. A command device that generates a brake command as an electrical signal, a receiver that amplifies and outputs the electrical signal from this command device, and an electro-pneumatic device that sends fluid at a pressure according to the electrical signal from this receiver. A conversion valve is provided, and the command device and the receiver are provided in the leading car of the train set, and the electro-pneumatic conversion valve is provided in each car of the train set, and the solenoid of the electro-pneumatic conversion valve is connected to the receiver. A compensation device that is connected in parallel to the lead-in line from the receiver, and changes the output of the receiver in response to temperature changes so as to maintain a constant current flowing through the solenoid of the electro-pneumatic conversion valve. A vehicle brake device characterized by being provided with a circuit.