JPH0356444Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) This invention relates to a parking brake system for a vehicle equipped with two driver seats.

(Prior Art) For example, there are known vehicles such as alternating cars that have a driver's seat in the driver's seat on the upper side in addition to the driver's seat on the bogie side. The brake can be activated and released at will from either driver's seat.
Utility Application No. 57-177809 and No. 57-
Proposed in No. 195216.

For example, as shown in FIG. 4, an air pressure passage 3 connecting an air pressure tank 1 and a spring brake chamber 2
A solenoid valve 4 is interposed in the middle.

The solenoid valve 4 has a position 4A that closes the air pressure passage 3 and a position 4B that opens the air pressure passage 3 to the atmosphere, and is designed to maintain the position 4a when energized.

Reference numeral 5 denotes a drive circuit for the electromagnetic valve 4, and in the middle of the drive circuit are installed changeover switches 7 and 8, which are respectively disposed on the driver's seats 6A and 6B on the truck side and the upper part side.

9 is a compressor that supplies air pressure to the air pressure tank 1; 10 is a brake operation indicator lamp 11 when the air pressure in the downstream passage 3 of the solenoid valve 4 is below a set value;
and 12 circuits 13 are shown.

In the illustrated brake released state, when either one of the changeover switches 7 and 8 is operated, the solenoid valve 4 is switched to release the air pressure in the spring brake chamber 2 to the atmosphere at position 4B. In other words, the parking brake is activated.

To release the parking brake, it is only necessary to switch either switch 7 or 8 again. In this case, the solenoid valve 4 switches to position 4A and supplies air pressure to the spring brake chamber 2, thereby releasing the spring brake. be done.

Therefore, since the parking brake can be operated arbitrarily from either driver's seat 6A, 6B, there is no need to transfer from the driver's seat 6B on the upper side to the driver's seat 6A on the trolley side each time the parking brake is operated. Workability can be improved.

(Problem to be solved by the invention) However, in the case of such a parking brake device, for example, when parking, the switch 7 is switched to the opposite side as shown in the figure to release the air pressure and apply the parking brake. There was a concern that if an operator other than the driver inadvertently touched the changeover switch in the cockpit, the parking brake would be released.

This invention was developed in view of these problems, and aims to propose a parking brake device that prevents the driver's seat on the engine key switch-off side from releasing the parking brake.

(Means for solving the problem) Therefore, this invention provides a parking brake device that allows the parking brake to be operated arbitrarily from either the driver's seat on the bogie side or the driver's seat on the upper object side.
The working pressure passage from the working pressure supply source is branched in the middle, a manual switching valve is installed on one side, and a first solenoid valve is installed on the other side, and these are joined downstream to form a second solenoid valve. In addition to connecting to the parking brake actuating section through the merging section, a differential pressure-responsive directional switching valve is provided at the merging section, and the engine key switch is connected to the driver's seat on at least the upper side of the upper side and the bogie side. a first drive circuit that supplies current to the first solenoid valve; and a second drive circuit that supplies switching current to the second solenoid valve via a switch provided on the driver's seat on the upper side. will be established.

(Function) That is, when the engine key switch on one driver's seat is turned on, the first solenoid valve is in the cutoff state and the second solenoid valve is in the cutoff state.
The solenoid valve becomes in communication, and in this case, the parking brake is activated and released by operating the manual switching valve.

In addition, when the engine key switch of the other driver's seat is on, the first solenoid valve is in communication state, and in this case, the parking brake is activated by switching the second solenoid valve via the changeover switch. Can be canceled.

(Example) In FIG. 1, 20 is an air pressure passage connecting the air pressure tank 1 and the spring brake chamber 2, and the air pressure passage 20 is branched into 20A and 20B in the middle, and a manual switching valve 21 is installed in one of them. , and a first electromagnetic valve 22 is interposed on the other side, and these are formed so as to join 20C downstream and reach the spring brake chamber 2.

At the confluence of the air pressure passages 20A and 20B,
A directional switching valve 23 is provided which switches depending on the internal pressure of each passage.

This directional switching valve 23 connects the voltage side of the passages 20A and 20B to the downstream merging passage 20C,
It is a pressure-responsive valve that shuts off the other. Further, a second electromagnetic valve 2 is interposed downstream of the directional switching valve 23.

The first and second solenoid valves 22 and 24 each have a position in which the upstream and downstream sides of the air pressure passages 20A and 20C are communicated, and a position in which the upstream side is shut off and the downstream side is opened to the atmosphere. Excitation coils 22A, 24A for switching to the side position and excitation coil 22 for switching to the cutoff side position.
B, 24B, and once the position is switched, the excitation coils 22A, 22B and 24A,
It is designed to maintain its position even if the power supply to 24B is cut off (so-called lock type).
The manual switching valve 21 is disposed on the driver's seat 6A on the truck side, and has a communication side and a cutoff (atmospheric release) side position, like the first and second solenoid valves 22 and 24.
The switching position is maintained by manual operation.

25 is a drive circuit for the first and second solenoid valves 22, 24, and this drive circuit 25 is connected to a first drive circuit 25A that supplies battery current via an engine key switch 26 disposed in the driver's seat 6A on the bogie side. and a second drive circuit 25 that supplies battery current via the engine key switch 27 of the driver's seat 6B on the upper side.
It consists of B.

When the engine key switch 26 is turned on, the first drive circuit 25A energizes the excitation coil 22B on the cutoff side of the first solenoid valve 22, and also energizes the excitation coil 22B on the communication side of the second solenoid valve 24 via a pressure switch 28, which will be described later. The excitation coil 24A is energized.

On the other hand, when the engine key switch 27 is on, the second drive circuit 25B operates the first solenoid valve 25B.
The excitation coil 22A on the communication side of the second electromagnetic valve 24 is energized, and the excitation coils 24A and 24B on the communication side and cutoff side of the second solenoid valve 24 are selectively energized via the changeover switch 29.

The pressure switch 28 causes the air pressure between the manual switching valve 21 and the directional switching valve 23 to exceed the set value, that is, the air pressure from the air pressure tank 1 reaches the manual switching valve 21.
It turns on when supplied through the .

The changeover switch 29 is disposed on the driver's seat 6B on the upper side, and when the changeover switch 29 is manually changed over, the second solenoid valve 24 is changed over between a communication position and a cutoff position.

In addition, 30 is a pressure switch that is turned on when the air pressure between the spring brake chamber 2 and the second solenoid valve 24 is below a set value, and 12 is a driver's seat 6 on the upper side.
Parking brake operation indicator lamp installed in B, 13
is a parking brake operation display lamp provided on the driver's seat 6A on the bogie side, and these lamps 11 and 12 light up when the engine key switches 26 and 27 are turned on and the pressure switch 30 is turned on (that is, when the brake is activated).

31 indicates a diode.

Next, the effect will be explained.

When the parking brake switch is released from the driver's seat 6A on the truck side, the engine key switch 26 is turned on and the manual changeover valve 21 is switched to the communication position. At the same time, the air pressure from the air pressure tank 1 passes through the manual switching valve 21 and cuts off the air pressure passage 20 on the side of the directional switching valve 23 (low pressure first solenoid valve 22). , which connects the passage 20 on the high-pressure manual switching valve 21 side to the downstream side) to reach the second electromagnetic valve 24.

The second solenoid valve 24 is energized via the pressure switch 28 (turned on by switching the manual switching valve 21) to the excitation coil 24A on the communication side, and in the communication position, air pressure is applied to the spring brake via the directional switching valve 23. The parking brake is then released.

In this state (engine key switch 26 on the truck side
is on), in order to operate the parking brake, it is sufficient to switch the manual switching valve 21 to the cutoff position; in this case, the spring brake chamber 2
The air pressure inside is controlled by the second solenoid valve 24 and the directional control valve 23.
It is opened to the atmosphere through a manual switching valve 21, thereby operating the parking brake.

Note that the pressure switch 28 is turned on when the air pressure of the manual switching valve 21 is released, but the pressure switch 28 is turned on when the air pressure of the manual switching valve 21 is released.
4 is a lock type and maintains the communication position.

When the air pressure in the spring brake chamber 2 falls below the set value, the pressure switch 30 is turned on and the brake operation indicator lamp 11 lights up.After the driver confirms this, the engine key switch 26 is turned on. Just cut it.

On the other hand, when releasing the parking brake from the driver's seat 6B on the upper side, when the engine key switch 27 is turned on, the first solenoid valve 22 is switched to the communication side, and the air pressure in the air pressure tank 1 is accordingly changed. is (when the manual switching valve 21 is on the cutoff side) the first solenoid valve 2
2. A second electromagnetic valve 24 via a directional switching valve 23 (connecting the high-pressure side upstream passage 20B to the downstream passage 20C)
reach.

In this state, when the changeover switch 29 is set to the travel side (brake release side), the second solenoid valve 24 is in the communication position and supplies air pressure from the direction changeover valve 23 to the spring brake chamber 2, thereby causing the parking The brake is released.

To operate the parking brake, turn on the engine key switch 27 and press the changeover switch 29.
It is sufficient to switch to the parking side (brake activation side), and at this time, the second solenoid valve 24 is switched to the cutoff side to release the air pressure in the spring brake chamber 2 to the atmosphere and operate the spring brake.

Then, when the pressure switch 30 is turned on in the same manner as described above, the brake operation indicator lamp 12 lights up.

In addition, when releasing the parking brake, temporarily release the manual switching valve 2.
1 is in communication, and even if the directional switching valve 23 is not switched as the first electromagnetic valve 22 is communicated, air pressure from the manual switching valve 21 side is supplied to the second electromagnetic valve 24 side. Therefore, the parking brake is released by operating the changeover switch 29.

With this configuration, for example, even if a worker who enters the upper cockpit operates the changeover switch 29 while the driver is operating the parking brake in the driver's seat 6A on the bogie side, the engine key switch will not be activated. The parking brake will not be released unless the engine key 27 is turned on, and since the engine key is usually in the possession of the driver, the brake cannot be released by mischief or by mistake.

Incidentally, in this embodiment, when both the engine key switches 26 and 27 are off, the parking brake may not be activated even if the manual changeover valve 21 and the changeover switch 29 are operated.

For example, even if you operate the manual switching valve 21 to operate the parking brake after turning off the engine key switch 27 and getting out of the driver's seat 6B on the upper side, the spring brake chamber 2 will not be connected to the first solenoid valve 2.
2. When communicating with the air pressure tank 1 via the directional control valve 23 and the second solenoid valve 24, the brake cannot be operated unless the engine key switch 26 is turned on.

Therefore, in the second embodiment shown in FIG. 2, the first electromagnetic valve 22 is changed to a lock type so that the parking brake can be operated by operating the manual switching valve 21 even when the engine key switches 26 and 27 are both off. The air pressure passage 20 on the upstream side is shut off and the air pressure passage 2 on the downstream side is connected only when energized.
A normally closed type (opening 0 to the atmosphere) is adopted.

The first solenoid valve 22 is not interlocked with the engine key switch 26 on the truck side, and is energized only when the engine key switch 27 on the upper truck side is turned on.

According to this, the upper engine key switch 2
7 is off, the first electromagnetic valve 22 is in the cutoff state, so even if the engine key switch 26 on the bogie side is off, when the manual changeover valve 21 is switched to the cutoff side, the air inside the spring brake chamber 2 is turned off. The air pressure passes through the second solenoid valve 24 and the directional switching valve 23 and is released to the atmosphere at the manual switching valve 21, so that the parking brake can be operated.

Of course, when the manual switching valve 21 is on the cutoff side, the parking brake is activated at the same time as the engine key switch 27 is turned off.

In the third embodiment shown in FIG.
is connected to the engine key switch 2.
The parking brake can also be operated by operating the changeover switch 32 after turning off the parking brake.

However, a relay 34 is interposed in the drive circuit 25B to prevent the brake from being released even if the changeover switch 32 is switched to the brake release side when the engine key switch 27 is off.

Note that the changeover switch 32 is automatically returned to the neutral position by the action of a spring.

(Effects of the invention) In summary, according to this invention, in a parking brake device that allows the parking brake to be operated arbitrarily from either the driver's seat on the bogie side or the driver's seat on the upper part, the actuation from the operating pressure supply source is provided. The pressure passage is branched in the middle, a manual switching valve is installed on one side, and a first solenoid valve is installed on the other side, and these are merged downstream and then connected to the parking brake actuating section via the second solenoid valve. At the same time, a differential pressure-responsive directional control valve is provided at the merging section, and the first electromagnetic valve is connected to the first solenoid valve via an engine key switch installed in the driver's seat on at least the upper side of the upper side and the truck side. A first drive circuit that supplies current and a second drive circuit that supplies switching current to the second electromagnetic valve via a switch installed on the driver's seat on the upper side are provided, so the engine key Even if a worker operates the parking brake from the driver's seat on the off-side of the switch, the parking brake will not be released, thus significantly improving the operational safety of vehicles equipped with this type of parking brake device. You can get the effect that you can.

[Brief explanation of drawings]

Fig. 1 is a schematic diagram showing the first embodiment of this invention, Fig. 2 is a schematic diagram of the second embodiment, Fig. 3 is a schematic diagram of the third embodiment, and Fig. 4 is a conventional example. FIG. DESCRIPTION OF SYMBOLS 1... Air pressure tank, 2... Spring brake chamber, 6A, 6B... Driver's seat, 20... Air pressure passage, 21... Manual switching valve, 22... First solenoid valve, 23... Direction switching Valve, 24... Second electromagnetic valve, 25A... First drive circuit, 25B... Second drive circuit, 26, 27... Engine key switch, 29... Changeover switch.

Claims (1)

[Scope of utility model registration request] In a parking brake device that allows the parking brake to be operated arbitrarily from either the driver's seat on the bogie side or the driver's seat on the upper side, the operating pressure passage from the operating pressure supply source is branched midway, and one side is operated manually. A switching valve is installed on the other side, and a first solenoid valve is installed on the other side, and these are connected downstream and further connected to the parking brake actuating part via the second solenoid valve. a first drive circuit that supplies a current to the first electromagnetic valve via an engine key switch provided in a driver's seat on at least the upper side of the upper side and the truck side; A parking brake device comprising: a second drive circuit that supplies a switching current to the second electromagnetic valve via a switching switch provided on a side driver's seat.