JP2002211370A - Erroneous start prevention system of trailer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an erroneous start prevention system of a trailer capable of avoiding danger due to erroneous start. SOLUTION: This tank-type trailer is provided with a spring brake chamber 10 consisting of a service brake part 10A and a spring brake part 10B and an antilock brake system adjusting a brake pressure. This erroneous start prevention system of the trailer has a parking brake valve 42 connected to the spring brake part 10B to release air in the spring brake part 10B in the interlocking relationship with opening of a door 45 of a valve easing 44, a solenoid valve 41 connected between the spring brake part 10B and the parking brake valve 42 to switch the communication between both of them and shutting-off of the communication, and a relay part 50 receiving a control signal from a computer 51 to control current carrying and non-current carrying of the solenoid valve 41 with power supply.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a trailer having a tank in which various oils and other liquids are loaded.
The present invention relates to a false start prevention system during unloading and other operations.

[0002]

2. Description of the Related Art FIG. 5 is a side view showing a tank type trailer connected to a tractor. Trailer 100
Is connected to a tractor 200, which is a towing vehicle, at a mounting portion 202 of a rear frame 201 so as to be able to swing right and left. The trailer 100 has a tank 102 integrally mounted on a frame 101 by welding or the like, and rear wheels 103, 1 behind the frame 101.
03. The tank 102 constitutes a closed space in which the front and rear ends are cylindrical with a head plate.
A protector 104 for protecting the safety valve is formed at the top,
Below, a valve box 105 with a main valve for unloading cargo
Is provided. On the other hand, a tractor 200 which is a towing vehicle provided with a cab 203 has a rear frame 201 extending behind the cab 203 and has wheels 204 and 204 in front and rear.

[0003]

However, such a conventional trailer 100 does not have a system for preventing erroneous starting, so that it is necessary to immediately consider measures for the following situations. Usually, trailer 1
To unload the liquid loaded in 00, open the door of the valve box 105, extend the attached hose 106, connect to the supply destination, open the main valve, perform unloading, and then close the main valve. The hose 106 is stored in the hose case 107 again, and the operation is completed. However, if the trailer 100 is started by mistake while discharging the loaded liquid, the hose 106 comes off and the liquid leaks out. In such a case, it is not difficult to imagine that the situation would be dangerous because the liquids handled are petroleum and liquefied gas.

It is an object of the present invention to provide a trailer erroneous start prevention system that avoids danger caused by erroneous start.

[0005]

SUMMARY OF THE INVENTION A trailer erroneous start prevention system according to the present invention has a service brake unit for a service brake for operating a brake by air supplied by depressing a brake pedal, and a pressurized state. A spring brake chamber consisting of a spring brake section that operates a brake by the restoring force of the spring by bleeding air, and a pulse signal from a wheel speed sensor is sent to a computer to determine the rotation state of the wheel and to determine the rotation state of the wheel, and An anti-lock brake system for adjusting air pressure, a tank-type trailer for opening a main valve that stores a liquid mounted in a tank in a valve box and unloading the tank, wherein the spring brake unit is provided. Connected to the valve box, A parking brake valve that releases air in a ring brake unit, a solenoid valve that is connected between the spring brake unit and the parking brake valve to switch between communication and shutoff between the two, and a control signal from the computer. receive,
A relay section for controlling energization and non-energization of the solenoid valve with a power supply.

Therefore, according to the present invention, when the door of the valve box is opened, the air is released by the parking brake valve associated therewith, and the spring brake operates to apply the parking brake. Therefore, when unloading the liquid loaded on the trailer, the door of the valve box is always opened, so that the erroneous start can be reliably prevented. In addition, the vehicle's speed signal from the anti-lock brake system is used to provide an interlock function that shuts off the connection between the spring brake and the parking brake valve during driving. Even in the event of an accident, it is possible to avoid the danger of unexpected sudden braking that has nothing to do with the driver's will.

Further, the system for preventing a false start of a trailer according to the present invention includes a second parking brake valve connected downstream of the parking brake valve, wherein the upstream parking brake valve is connected to an atmosphere release port and a second port. The second parking brake valve is a normally-closed on-off valve that opens and closes to an atmosphere release port. Therefore, according to the present invention, when unloading the liquid loaded on the trailer, erroneous starting can be reliably prevented, and even in the case of normal parking with the valve box door closed without unloading, etc. The parking brake can be applied by opening the second parking brake valve.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of a system for preventing erroneous starting of a trailer according to the present invention will be described below with reference to the drawings. FIG. 1 is a partial sectional view showing a general brake device of a trailer using a spring brake chamber. The trailer uses a drum brake using air as a working fluid for obtaining a strong braking force. In the brake device, a brake drum 2 is rotatably attached to an axle tube 1, a brake shoe 3 is expanded from the inside, and a braking force is applied by a frictional force with a lining (not shown). In order to extend the brake shoe 3, the linear motion output of the push rod 11 protruding from the spring brake chamber 10 is transmitted to the camshaft 5 instead of the rotary motion by the slack adjuster 4, and fixed to the tip of the camshaft 5. A mechanism is performed by rotating the cam 6.

FIG. 2 shows the spring brake chamber 10.
It is sectional drawing which showed. The spring brake chamber 10 operates for a service brake and for a parking brake.
0A and a spring brake portion 10B. In one service brake unit 10A, a push rod 11 is fixed to a diaphragm 13 mounted in a body 12, and a spring 14 for urging the diaphragm 13 in a direction to contract the push rod 11 is mounted.

Further, the other spring brake unit 1
0B is the spring 1 mounted in the body 15 thereof.
A piston 17 that slides under a load of 6 is inserted, and a release 18 is fixed through the center of the piston 17. Further, the piston 17 is abutted on the diaphragm 13 which is bent upward as shown in FIG. And these upper and lower bodies 1
The ports 2 and 15 are formed with ports 19 and 20 for supplying and exhausting air to the side where both springs 14 and 16 are compressed.

Next, this trailer has an anti-lock brake system (hereinafter referred to as "A") for detecting the rotational speed of the wheels.
BS "), and as shown in FIG.
The wheel speed sensor 7 is mounted so as to face a sensor ring (not shown) in which irregularities of a fixed number of teeth are cut. A
The BS sends a pulse signal from the wheel speed sensor 7 to the ABS computer because the frequency of the pulse signal generated by electromagnetic induction between the BS and the sensor ring is proportional to the wheel speed, and determines the rotation state of the wheel. The electronic control is performed such that the air pressure of the brake is adjusted according to various road surface conditions.

FIG. 3 is a block diagram showing a trailer erroneous start prevention system (hereinafter simply referred to as an "erroneous start prevention system") according to the present embodiment. This false start prevention system utilizes the existing brake system and ABS in the trailer. Therefore, first, a general brake system of a trailer will be described.
Since the configuration of both the left and right wheels shown in FIG. 3 is symmetrical, in the following description, only the configuration on one side will be described for overlapping parts. The brake system of the trailer is controlled in conjunction with the tractor's spring brake operating air system, and operates the drum brake via a spring brake chamber 10 as shown in FIG. is there. Currently,
Those equipped with such a spring brake chamber 10 are becoming popular.

First, AB for adjusting the brake pressure of the wheels
It has a modulator 30 for S, in which a relay valve 31 is connected to the port 19 of the service brake unit 10A constituting the spring brake chamber 10 (see FIG. 2).
Is connected to The relay valve 31 is connected to an air tank 32 so that air of a predetermined pressure can be constantly supplied to the service brake unit 10A, and further connected to a relay emergency valve 33 that controls the supply of a brake operation signal pressure. An air tank 32 is connected to the relay emergency valve 33, and a service line 34 for sending a brake operation signal pressure from a brake valve on the tractor side.
And an emergency line 35 for sending air from the tractor side and controlling the operation of the emergency brake in an emergency.

Subsequently, in this embodiment, in addition to such a brake system, a spring brake chamber 10 is provided.
(See FIG. 2). In particular, the present embodiment is characterized not only by simply preventing erroneous starting during work, but also by providing an interlock mechanism using ABS as a fail-safe structure as an emergency stop prevention measure during normal traveling. Have. Therefore, the main configuration of the false start prevention system will be described with reference to FIG.

A solenoid valve 41 for switching between two positions is connected to a port 20 (see FIG. 2) of the spring brake section 10B of the spring brake chamber 10, and an air tank 32 connected through the solenoid valve 41 constantly supplies air. Is supplied to the spring brake section 10B. On the other hand, to another port of the solenoid valve 41, two parking brake valves 42 and 43 for discharging air in the spring brake portion 10B to the atmosphere are connected in series. The upstream parking brake valve 42 is provided with a valve box 44 (FIG. 5).
, And the downstream parking brake valve 43 is installed outside the valve box 44.

FIG. 4 is a diagram conceptually showing a partial configuration of the present system in the valve box 44. As shown in FIG. The valve box 44 is provided with a door 45. Therefore, when unloading the liquid loaded on the trailer, the door 45 is always opened, so that the unloading operation can be confirmed by opening and closing the door 45. In this system, such a door 45
The parking brake valve 42 is operated in conjunction with the opening and closing of the vehicle. An arm 46 that swings about a fulcrum S is mounted in the valve box 44, and one of the arms 46 is urged toward the door 45 by a spring 47, and the other is connected to a plunger of a parking brake valve 42 that operates a valve element. Have been.

As described above, the parking brake valve 4
Reference numeral 2 denotes a three-port valve which operates by indirectly receiving opening / closing information of the door 45 via the arm 46, and operates when the door 45 is opened, and when the door 45 is closed, a downstream parking brake is provided. The valve is switched to a port on the valve 43 side. on the other hand,
The downstream parking brake valve 43 is an open / close valve having an atmosphere release port, and is a normally closed type in which the valve is normally closed.

Next, the interlock mechanism of the erroneous start prevention system includes a CPU (hereinafter referred to as "ABS C
The solenoid valve 41 is driven and controlled based on a vehicle speed signal from the PU 51). That is, the solenoid valve 41 is disposed upstream of the parking brake valve 42, and the spring brake unit 10B
Acts to prevent unexpected air bleeding. The solenoid valve 41 is connected to a power supply via a relay unit 50, and the relay unit 50
The solenoid valve 41 is controlled by a control signal from the PU 51.
And a power supply. The control signal is
A power ON / OFF signal for receiving a signal from the wheel sensor 7 that senses a vehicle speed equal to or higher than a predetermined value and operating the relay unit 50. The solenoid valve 41 shuts off the flow path on the side of the parking brake valve 42 when power is supplied, as shown in the figure.

Next, the operation of the erroneous start prevention system according to the present embodiment will be described. First, the spring brake chamber 10 has its spring brake portion 10B
The air is constantly supplied from an air tank 32 to the spring 17 and the spring 16 is compressed and contracted as shown in FIG.
Is located above. On the other hand, the service brake unit 10
The air to A is shut off, and the push rod 11 is pushed up by the spring 14. During traveling, the spring brake chamber 10 is in such a state, and the trailer is in a no-brake state.

For example, when the brake pedal is depressed on the tractor side during traveling, a brake operation signal pressure is supplied through the service line 34, and the air in the air tank 32 flows by the operation of the relay emergency valve 33. The air is supplied to the service brake unit 10A of the spring brake chamber 10 via the relay valve 31. Therefore, in the service brake unit 10A in the state shown in FIG. 2, the diaphragm 13 is pressurized by the supplied air, the spring 14 is pressed and contracted, and the push rod 11 extends downward. The linear motion output of the push rod 11 is changed into a rotational motion by the slack adjuster 4, and rotation is given to the cam 6 fixed to the tip of the cam shaft 5 (see FIG. 1).
Then, the brake shoe 3 is expanded by the movement of the cam 6, and a braking force is exerted by a frictional force of the lining (not shown) with the brake drum 2, thereby applying a brake to the trailer.

On the other hand, when the brake pedal is released on the tractor side, the air of the brake operation signal pressure in the service line 34 is released from the tractor side brake valve to the atmosphere. Therefore, the relay emergency valve 33 and the relay valve 31 operate in conjunction therewith, and the air in the service brake unit 10A is released from the relay valve 31. And the spring brake chamber 10
In this case, since the push rod 11 is pulled upward by the restoring force of the spring 14, the reverse rotation is given to the cam 6 at the tip of the cam shaft 5 via the slack adjuster 4, and the brake is released (see FIGS. 1 and 2). ).

In this brake system, ABS / CP
The rotation state of the wheel 9 based on the wheel speed signal from the wheel speed sensor 7 is monitored by U51. Therefore, when it is determined that the wheels 9 have a tendency to lock when the trailer is suddenly braked, an ABS control signal is output from the ABS / CPU 51 to the modulator 30, and the control valve of the modulator 30 controls the inside of the service brake unit 10A. The brake pressure is adjusted by increasing or decreasing or maintaining the brake pressure. In this brake system, the emergency line 35 is released to the atmosphere in an emergency such as when the tractor and the trailer are separated. In this case, the relay emergency valve 33 is actuated, and the service brake unit 10A is connected from the air tank 32 via the relay valve 31.
Is supplied to the air. Therefore, the service brake unit 10A functions in the same manner as described above in which the brake pedal is depressed, and the emergency braking is applied to the separated trailer.

Next, a case where the liquid loaded on the trailer is unloaded will be described. As described above, the rotation status of the wheels 9 of the trailer is monitored by the ABS CPU 51, and the traveling speed is confirmed. Therefore, during traveling, a wheel speed signal is transmitted from the wheel speed sensor 7, whereby a power-off signal is transmitted from the ABS / CPU 51 to the relay unit 50. Therefore, the solenoid valve 41, which is powered and de-energized by the relay unit 50, connects the spring brake unit 10B and the parking brake valve 4
2 is in a state of blocking the flow path. On the other hand, when the wheel speed signal is not transmitted from the wheel speed sensor 7 by stopping the trailer at the unloading place or the like, a power ON signal is transmitted from the ABS / CPU 51 to the relay unit 50, and the power is supplied to the power source. The solenoid valve 41 is connected to the spring brake unit 10.
The valve is switched so as to communicate the flow path between B and the parking brake valve 42.

Next, when the liquid is unloaded from the trailer, the valve box 44 is opened, and the provided hose 106 is extended from the hose case 107 shown in FIG. 5 and connected to the supply destination. At that time, when the door 45 of the valve box 44 is opened, the spring 47 which has been compressed and contracted by the door 45 expands, and the arm 46 swings about the fulcrum S (the state shown in FIG. 4), and the opposite side. The plunger of the parking brake valve 42 connected to is pressed. At this time, the parking brake valve 42 is connected to the downstream parking brake valve 4.
The valve is switched so as to change the flow path from the port connected to the third side to the atmosphere release port side. Then, the air in the spring brake portion 10B communicated via the solenoid valve 41 is discharged as shown by an arrow F1 in FIG.

In the spring brake chamber 10 in the state shown in FIG. 2 due to the air pressure, the spring 16 is extended by the release of air, and the piston 17
, The push rod 11 is pushed down via the sleeve 21. Then, since the cam 6 that has been rotated through the slack adjuster 4 expands the brake shoe 3, a parking brake is applied to the trailer (see FIG. 1). Therefore, in the past, the parking brake was applied to the trailer by manually rotating the slack adjuster 4, but according to this erroneous start prevention system, the same parking can be performed only by opening the door 45 of the valve box 44. Action will be taken.

Subsequently, when the door 45 of the valve box 44 is closed after the work is completed, the arm 46 swings about the fulcrum S so as to press and contract the spring 47, and the parking brake valve 42
Is switched again to the port on the parking brake valve 43 side. Thereby, the air from the air tank 32 is supplied to the spring brake portion 10B, and the piston 17 pressurized by the air compresses the spring 16 and rises again. And in the service brake unit 10A,
Since the push rod 11 is pushed up by the spring 14, the parking brake is released.

Thereafter, when the trailer starts moving and the traveling speed exceeds a certain level, a wheel speed signal is sent from the wheel speed sensor 7 as described above, and the relay
0, a power OFF signal is sent to the solenoid valve 41 that has been de-energized with the power.
Switching is performed so as to shut off the flow path between the parking brake valve 42 and the parking brake valve 42. Therefore, during traveling, the valve box 4
Even if the door 45 is opened, the air in the spring brake section 10B is not released, so that the emergency braking is not suddenly applied regardless of the driver's intention.

In the case where the vehicle is simply parked instead of unloading the liquid, the door 45 of the valve box 44 cannot be left open to apply the parking brake to the trailer. Therefore, in such a case, the flow path connected to the spring brake unit 10B is released to the atmosphere by operating the parking brake 43 on the downstream side. When the door 45 of the valve box 44 is closed, the flow path of the downstream parking brake valve 4 is controlled by the parking brake valve 42.
It communicates with 3. Therefore, when the parking brake valve 43 is opened, the air in the spring brake portion 10B is released as shown by the arrow F2 in FIG. 3, and the trailer is operated similarly to the case where the parking brake valve 42 is operated. The parking brake is applied. When the parking brake valve 43 is closed again, the parking brake is released.

As described above, according to the erroneous starting prevention system of the present embodiment, the brake is applied in conjunction with the opening and closing of the door 45. Therefore, when the liquid loaded on the trailer is unloaded, the door of the valve box 44 is unloaded. Since the opening 45 is always opened, the erroneous start can be surely prevented. In addition, since the erroneous start prevention system is configured by using the spring brake unit 10B provided for parking, it can function safely. That is, if the service brake unit 10A for the service brake is used, when a trouble occurs, sudden braking may be applied,
Conversely, there is a risk of no braking, but such a problem cannot occur with this system.

As described above, the ABS / CPU
By providing the interlock function using the trailer's vehicle speed signal from 51, the door 45 of the valve box 44 should be
Even if the vehicle is opened, there is no risk of causing a dangerous situation in which sudden braking is suddenly applied regardless of the driver's will. Further, since the parking brake is linked to the opening and closing of the door 45 of the valve box 44, a special operation for parking the trailer is not required, and the means for preventing erroneous starting can be reliably functioned. Therefore, by summarizing the above, it is possible to secure the safe operation of the trailer, the unloading operation, and the like by the false start prevention system of the present embodiment.

Although an embodiment of the erroneous start prevention system according to the present invention has been described, the present invention is not limited to this, and various modifications can be made without departing from the spirit of the present invention. For example, although the solenoid valve 41 is a two-position switching valve, the air tank 32 may be directly connected to the spring brake unit 10B to be an on-off valve.

[0032]

According to the present invention, there is provided a parking brake valve which is connected to a spring brake portion and releases air in the spring brake portion in response to opening of a valve box door, a spring brake portion and a parking brake valve. A solenoid valve connected between the solenoid valves for switching between communication and cutoff between the two, and a relay unit that receives a control signal from a computer and controls energization and de-energization with a power supply of the solenoid valve. As a result, it is possible to provide a system for preventing a trailer from mis-starting, which avoids danger caused by a wrong start.

[Brief description of the drawings]

FIG. 1 is a partial sectional view showing a general brake device of a trailer using a spring brake chamber.

FIG. 2 is a sectional view showing a spring brake chamber.

FIG. 3 is a block diagram showing one embodiment of a system for preventing a false start of a trailer.

FIG. 4 is a diagram conceptually showing a partial configuration of the present system in a valve box.

FIG. 5 is a side view showing a tank type trailer connected to a tractor.

[Explanation of symbols]

 7 Wheel speed sensor 10 Spring brake chamber 10A Service brake unit 10B Spring brake unit 41 Solenoid valve 42 Parking brake valve 44 Valve box 45 Door 50 Relay unit 51 ABS / CPU

Claims (2)

[Claims] 1. A service brake portion for a service brake for operating a brake by air supplied by depressing a brake pedal, and a spring brake for operating a brake by restoring force of a spring by releasing air in a pressurized state. And an anti-lock brake system that sends a pulse signal from a wheel speed sensor to a computer, determines the rotation state of the wheel, and adjusts the air pressure in the service brake unit. A tank-type trailer for opening and unloading a main valve storing a liquid mounted in a tank in a valve box, wherein the trailer is connected to the spring brake unit and interlocks with opening of the valve box door. Parking brake valve that releases air from the spring brake section A solenoid valve connected between the spring brake portion and the parking brake valve for switching between communication and shutoff between the two; and energization of a power supply for the solenoid valve in response to a control signal from the computer. And a relay unit for controlling non-energization. 2. The system according to claim 1, further comprising a second parking brake valve connected downstream of the parking brake valve, wherein the upstream parking brake valve is connected to an atmosphere release port. Erroneous starting of a trailer, wherein the second parking brake valve is a normally closed on-off valve having an atmosphere release port. Prevention system.