JPH01164655A - Brake pressure control device for trailer - Google Patents

Abstract

PURPOSE:To make a load sensing valve with a complex structure unnecessary and reduce the cost by changing the feed pressure to a relay valve with a limiting valve via the control pressure fed through solenoid valves switched by the electrical command from a tractor side. CONSTITUTION:An air reservoir is connected to the input port side of a brake valve 1 operated by a driver via a pipeline 2, and a service port is connected to solenoid valves 4 and 5 via a pipeline 3. The solenoid valves 4 and 5 are connected to limiting quick release valves 8 and 9 via pipelines 6 and 7, output ports of the valves 8 and 9 are connected to brake chambers 16 and 17 via a check valve device 10 and a relay emergency valve 13. The solenoid valves 4 and 5 are on or off-controlled when a driver selectively operates a switch device 19 in response to the load condition, thereby the maximum pressure at the check valve device 10 is changed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application 1] The present invention relates to a brake pressure control device for a trailer towed by a tractor.

[Prior art and its problems 1 For example, in Japanese Patent Application Laid-Open No. 52-111126'i'J',
The piping system for a trailer is disclosed, but the degree of braking force required varies depending on the size of the cargo on the trailer.
It is conceivable to install a load sensing valve as shown in Publication No. 24709 in the brake piping of the trailer as disclosed in the above publication, but it is difficult to obtain an appropriate braking force by adjusting the mounting accuracy of this load sensing valve. It's becoming difficult (ru).

[Problem to be Solved by the Invention 1] The present invention has been made in view of the above points, and provides a brake pressure control device for a trailer that can obtain an appropriate braking force according to the load when the trailer is full. The purpose is to

Means for Solving Problem E 1 The purpose of the above is to supply pressure supplied from the tractor side to the relay valve to operate the relay valve, and to supply air from the trailer side burner to the relay valve. In the river brake pressure control device, the relay valve is controlled through a solenoid valve that is switched by an electric command from the tractor side on the tractor side of the relay valve. This is achieved by a trailer brake pressure control device that is provided with a restriction valve that is supplied with pressure and changes the supply pressure of relay I in accordance with the supplied pressure.

[Effect 1] The control pressure supplied through the solenoid valve, which is switched by an electric command from the tractor side, is used to change the supply pressure to the relay valve from the limit valve, which eliminates the need for conventional load sensing bells with a complicated structure. There is no need to provide a brake, and the braking force can be changed appropriately according to the load.

[Embodiment 1] Fig. 1 shows a piping system and wiring system diagram of a brake pressure control device for l/railer according to an embodiment of the present invention. Indicates each member provided on the trailer side. Brake valve (1) on the tractor side
is equipped with a brake petal (la) operated by the driver, and an air reservoir is connected to the human-powered boat side of the harbour, via conduit c2), and the service boat connects to conduit (3). through the solenoid valves (4) and (5), the solenoid valve (lυ(5) also connects to the conduits (6) and (7)
via similarly configured limiting quick release valves (8) (9), the details of which are shown in FIG.
) are connected, and these output boats are connected to two check valves (1
1) and (12) are connected to the brake chambers (16) and (17) via a relay emergency valve (13) and a conduit (15). The brake chambers (16x17) have a known construction and are connected to the wheels to be braked.

The solenoid valves (4 x 5) usually take the A or C position, respectively, and in the A position of the solenoid valve (4), the boats on both sides, that is, the pipes (3) and (6) are cut off. However, the pipe (6) is connected to a solenoid valve (
In 5), the C position is taken, and the pipe line (3) side and the pipe line (7) side are communicated with each other. Also, each solenoid valve (
4) When the solenoids S1 and S2 in (5) are energized with enough current to operate the solenoid valve, the solenoid valve (1
1) takes position B, and pipes (3) and (6) are communicated. The other solenoid valve (5) takes the C position, and the pipes (3) and (7) are cut off, but the pipe (7) is allowed to communicate with the atmosphere. The details of the limiting quick release valves (8) and (9) are shown in Figure 2, and the pipe line (6) connected to the solenoid valve (4) is connected to the input chamber of the quick release valve (8). The conduit (7) connected to the solenoid valve (5) is connected to the control chamber of the limiting quick release valve (9), and the input chamber of this valve (9) has a conduit (7) connected to the solenoid valve (5). The above-mentioned conduit (3) is connected via the line (30). In addition, the check valves (11) and (12) in the check valve device qO are connected to the emergency valve (8) and (9) respectively from the valve (8) and (9) sides.
13) side is the forward direction, and this relay emergency valve (13) has an air reservoir l<(14
> is connected. Relay emergency valve (
13) has a well-known configuration, so a detailed explanation thereof will be omitted, but an emergency line is connected to it even though it is not shown in the drawings.

Next, to explain the wiring system, a 24V DC power supply is connected to a switch device (19) via a wiring (18) on the tractor side, and this movable contact (20) is connected to one of three fixed contacts (21822X23). It is possible to switch. The first fixed contact (21) is connected to the solenoid S1 of the solenoid valve (4) via a wiring (24), and is also connected to a constant voltage circuit (26) on the trailer side consisting of a transistor, a resistor, and a Zener diode. be done. Further, the second fixed contact (22) is in an OFF state, in other words, no voltage is supplied to the trailer side. Further, the third fixed contact (23) is connected to a constant voltage circuit (25) on the tractor side, which includes a transistor, a resistor, and a Zener diode. That is, when connecting the movable contact (20) to the first fixed contact (21) in the switching device (■9), 24V is applied to the solenoid S.
T-S! in this case both solenoid valves (4X
5) takes the B position and the C position. Furthermore, when the contact is switched to the second fixed contact (22), both of the solenoid valves (4) and (5) remain in the normal A position and C position. Also, when connected to the third fixed contact (23), the solenoid Sl of the solenoid valve (4) (5)
, S2 are each supplied with a voltage of 12V, but at this voltage, one solenoid valve (4) does not operate and remains at the 7~ position, but the other solenoid valve (5) takes the B position. It looks like this.

In addition, by applying voltages of 0124V and 12V to the solenoids Sl and S2 of the solenoid valves (4) and (5), each solenoid valve (4) and (5) can be switched (operation - 0N), non-operation = OFF.
, the pressure is exerted on these output boats (aXb)
The maximum pressure of the check valve device q■ when these are activated or not activated (however, the brake valve (1
), the maximum pressure of 6 kg f / c + j is written as follows.

Next, details of the limiting quick release valves (8) and (9) in FIG. 1 will be explained with reference to FIGS. 2 and 3. In addition, these valves (8) (9
) have the same configuration, so only one valve (9) will be described.

In Figures 2 and 3, the main body of the quick release valve (9) consists of an upper body (31) and a lower body (37), which are connected to a seal plate (38) by a bolt (39).
integrated through. A stepped hole (32) is formed in the main body thus formed, and the upper main body (31)
An input boat (33) is connected to the input boat (33) in communication with the stepped hole (32), and the pipe line (30) in FIG. 1 is connected to this. A control boat (34) is connected to the left end of the upper body (31), and the conduit (7) in FIG.
is connected. An exhaust port 35) is connected to the lower end of the lower body (37), and is communicated with the atmosphere via an exhaust vibrator (not shown in FIG. 1). As shown in FIG. 3, a service boat (36) is formed in the lower body (37) in communication with an output chamber (48) formed within the lower body, and this is connected to the filter pipe in FIG. (90). That is, it is connected to the check valve device (1).A stepped piston (40) fitted with seal rings (41) and (42) is slidable in the stepped hole (32) in the upper body (31). It is mated to
This is urged upward by a spring (45,) which is received by a spring receiver (46) fitted to the lower body (37), and is normally applied to the earthen wall of the upper body (31) as shown in the figure. It is in a position of contact.

A plurality of small holes (47) are formed in the spring receiver (46), and these provide constant communication between the space (49) in which the spring is disposed and the above-mentioned output chamber (48).

The stepped piston (40) has a tapered stepped hole (40
a) is formed, which defines an input chamber (44). A valve seat (40b) is formed in the tapered diameter-reduced portion of the tapered stepped hole (40a), and a valve seat (40b) is formed on this tapered stepped hole (40a).
An upper valve member (51) made of rubber fitted to the upper end of the valve rod (54) of 50) is seated in the normal position shown, and is fitted to the lower end of this rod (54). In the illustrated state, the valve member (52) made of rubber is separated from the valve seat of the tapered part (53) of the tapered stepped hole formed in the lower body (37). The main body of the release valve (9) is attached to a part of the vehicle body by a bolt (not shown) inserted into the attachment hole (55).The trailer brake pressure control device according to the embodiment of the present invention is constructed as described above. However, this effect will be explained next.

Now, when the driver of this trailer determines that the trailer is fully loaded, the movable contact (20) in the switching device (19) remains connected to the second fixed contact (22) as shown in the figure. put. If you drive in this state and now apply the brakes (depress the pedal (la) at the valve (1), the compressed air will pass through the pipe (3) to the solenoid valve (4) and then to the pipe (30). ) to the input port (33) of one quick release valve (9).Now, in the switching device (19), the movable contact (2
Since solenoid valve 0) is in the OFF position, no voltage is applied to either solenoid Sl or S2 of solenoid valves (4) and (5).
It remains in position A and C. In other words, a solenoid valve (
In 4), the compressed air from the brake valve (1) is now cut off by this solenoid valve (4) in position A, and is routed to the conduit (j), i.e. the quick release valve (8). ) side. Therefore, from this valve (8), check valve (7) flll
No compressed air is supplied to ll. On the other hand,
Since the solenoid valve (5) is in the CTL position, the compressed air from the valve (]) passes through the pipe line σ) to the quick
It is input to the control boat (34) of the release valve (9). This allows the quick release shown in Figure 2.
The stepped piston (40) in the valve (9) is lowered to provide an unrestricted pressure effect.

On the other hand, compressed air from the brake valve (1) flows through the pipe (3).
) and (30) to the quick release valve (
9) is supplied to the input chamber (44). This pressure is transmitted to the supply port (36) of this valve (9) in an unrestricted state, so the pressure at the input port (33) remains unchanged at the check valve (
I2) side. Therefore, this is the relay valve (
13) as an input, and compressed air from the reservoir (I4) is co-supplied to the brake chambers (16) and (17) via the conduit (15) according to this input, so that the brake valve In the unrestricted state of pressure (1), the output pressure corresponding to the input of the maximum pressure of 6 krf/cJ is supplied from the relay <13) to the brake chamber <16> (17), and the wheels connected thereto. The brakes are applied.

When releasing the brake, the brake chamber (1
6) The compressed air supplied to the input chamber (17) is released to the atmosphere from the outlet of the relay emergency valve (13), and the relay emergency valve (13)
The compressed air serving as the signal pressure is also released into the atmosphere from another outlet. Therefore, the brake is released.

Next, when the driver determines that the vehicle is loaded on the trailer, the switching device 19) switches the movable contact (20) to the first fixed contact (21). As a result, due to the action of the constant voltage circuit (26), the solenoid valve (
5) solenoid S2 is energized. In addition, since 24y is directly supplied to the solenoid S1 of the other solenoid valve (11), both solenoid valves (4) and (5) operate, and the solenoid valve (4)
takes the B position, and the other solenoid valve (5) takes the D position. Therefore, in the solenoid valve (4), compressed air from the brake valve (1) passes through the pipe line (3) and the passage at position B of the solenoid valve (4), and passes through the pipe line (6) to one quick - Supplied to the input port of the release valve (8). On the other hand, the compressed air from the brake valve (1) is transferred to the pipe (3).
The compressed air is supplied to the solenoid valve (5) through the pipe line (, 7), but since this solenoid valve (5) is now in position D, this compressed air
) side, the control chamber (43) of the other quick release valve (9) is in communication with the atmosphere, and this valve (9) is not in an unrestricted state. Therefore, by depressing the pedal (la) of the brake valve (1), compressed air passes through the solenoid valve (4) and the pipe (6).
Pressure of up to 2 kg/ctl is limited by the quick release valve (8) and the check valve (7)
as an input to the relay valve (13).

On the other hand, it is also supplied via conduits (3) and (30) to the input chamber (44) of the other quick-release valve (9), and now in these limiting conditions a pressure of up to 2 kg/c- is supplied to the other Relay valve (1) via check valve (12)
3). In the end, the maximum input is 4 kg/
ctl pressure is supplied (j%), and compressed air with a corresponding pressure is supplied from the relay valve (13) to the brake chamber (
16x17) and brakes the wheels connected to it.

Next, when the driver determines that the trailer is empty or nearly empty, the driver uses the switching device (19) to switch the movable contact (20) to the third fixed contact (23).
Switch to As a result, the constant voltage circuit (25) (26)
Due to this action, one of the solenoid valves (4) is also energized, but the current is not strong enough to switch it to the B position. The other solenoid valve (5) is switched to the D position. That is,
Since one solenoid valve (4) is in the on position, compressed air from the brake valve (1) is not supplied to the pipe (6), that is, one quick release bell (8) side. ζ, the other solenoid valve (5) is switched to position D, so the quick release valve (9)
acts as a restriction, and the pressure from the brake valve (1) is supplied to the input chamber (44), which receives the restriction action and transfers compressed air at a pressure of up to 2 kg/ci to the check valve (
12) to the relay valve (13). Therefore, a corresponding pressure is supplied to the brake chambers (16) and (17) via the pipe (I5). In other words, in this case, the maximum compressed air of 2 kg/cnf is supplied to the relay valve (13), so at the maximum, the lowest pressure is supplied to the brake chamber (16) (■7), and the load at this time Brakes can be applied to heavy wheels depending on the situation. .

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

For example, in the embodiment described above, two solenoid valves are used, and by selectively switching them, the quick release valve connected downstream can be operated in a restricted state or in a non-restricted state. We tried to obtain brake pressure in stages, but we also added two or more of these solenoid valves.
For example, three solenoids may be arranged, and by controlling each of these solenoids, the quick release valve connected thereto can be operated in a restricted state or in a non-restricted state, for example, as in the embodiment, to further increase the number of stages. The brake pressure may be controlled by

[Advantageous Effects of the Invention 1] As described above, the trailer brake pressure control device of the present invention does not use a mechanical load detection mechanism as in the past and control the brake pressure accordingly. Therefore, there is no need to install a complicated mechanical mechanism to the trailer piping system, and there is no fear that the appropriate braking force may not be obtained depending on the person. It is possible to supply appropriate braking force.

[Brief explanation of the drawing]

Fig. 1 is a piping system and wiring system diagram of a trailer brake pressure control device according to an embodiment of the present description, Fig. 2 is an enlarged sectional view of one quick release valve in Fig. 1, and Fig. 3 is an enlarged cross-sectional view of one of the quick release valves in Fig. 1. FIG. In addition, in the figure

Claims (1)

[Claims] Pressure supplied from the tractor side is supplied to the relay valve to operate the relay valve, and pressure proportional to the pressure supplied to the relay valve from the trailer side reservoir is supplied to the trailer side brake actuation device. In a trailer brake pressure control device, control pressure is supplied to the tractor side of the relay valve through a solenoid valve that is switched by an electric command from the tractor side, and the supply pressure to the relay valve is changed according to the supplied pressure. Brake pressure control device for trailers equipped with a limiting valve.