JPS583849B2 - Operating device of dump truck etc. - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention makes it possible to control the connection and disconnection of a power take-off device and the lifting and lowering of cargo boxes, etc. using an electrical system. This relates to an operating device for a dump truck, etc. that can control the connection and disconnection.

Embodiments of the present invention will be described below with reference to the drawings. 1 is a power take-off device installed in the transmission of an automobile engine; 2 is an air cylinder connected to the shifter portion of the power take-off device 1; 3 is an air tank; air tank 3
and the air cylinder 2 are connected through an air pipe 4.

A first switching valve 6 operated by a solenoid 5 is interposed in the middle of the air pipe 4, and by switching the first switching valve 6, the pressurized air in the air tank 3 is transferred to the base chamber or the tip chamber of the air cylinder 2. The air cylinder is expanded and contracted by flowing into the air, and the power take-off device is connected and disconnected.

On the other hand, 7 is a hydraulic pump driven by the power extracted from the power extraction device 1, and 8 is a cargo box 9 and a frame 10.
A hydraulic cylinder for lifting and lowering the cargo box is connected between the hydraulic pump 7 and the hydraulic cylinder 8 and tilts the cargo box 9 rearward around a hinge part (not shown).The hydraulic pump 7 and the hydraulic cylinder 8 are connected by a hydraulic pipe 11. There is.

A pair of solenoids 12, 1 are installed in the middle of the hydraulic piping 11.
A second switching valve 14 operated by 3 is interposed, and this second switching valve 14 is operated by
By switching the switching valve, hydraulic oil discharged from the hydraulic pump 7 flows into and out of the hydraulic cylinder 8, causing the hydraulic cylinder 8 to expand and contract, thereby raising, lowering, and stopping the cargo box 9.

Next, the electrical system that controls the energization of the solenoids 5, 12, and 13, respectively, will be explained with reference to FIG. , one end is connected to the main circuit 15, the other end is connected to the main operation switch S for lifting and lowering the cargo box, one end is connected to the upper contact 17 of the main operation switch S, and the other end is connected to the first switching valve. A first operating circuit 20 is connected to the solenoid 5 of No. 6, and has a diode 18 and a first switch r1 for a first relay interlocked with a Kuradzuchi petal 19 (described later) interposed therebetween, and one end is connected to the upper contact 17 of the main operation switch S. and connect the other end to the second
A second operating circuit 21 is connected to one solenoid 12 of the switching valve 14, and a second operating circuit 21 has one end connected to the lower contact 22 of the main operation switch S and the other end to the other solenoid 13 of the second switching valve 14. 3 operating circuit 23 and one end connected to main circuit 1
5, the other end is connected to the first relay R1, and the first auxiliary circuit 24 is interposed with a limit switch LS that is switched in conjunction with the operation of the clutch pedal 19, and one end is connected to the main circuit 15. The other end is the second relay R2
The second auxiliary circuit 25 is connected to the second auxiliary circuit 25.

The second auxiliary circuit 25 includes a circuit 26 including a second switch r2 for the second relay which switches between disconnection and connection when the second relay R2 is operated, and a circuit 26 which is switched by the operation of the first relay R1. The third switch r'1 for the first relay, which has an operation opposite to the first switch r1 for the first relay, and the main operation switch S are disconnected only when they are switched to the lower contact 22 position; (neutral contact, upper contact), the first operating circuit 20 and the second auxiliary circuit 25, the second relay R2 is activated when the solenoid 5 is energized by the first operating circuit 20, and even if the first switch r1 for the first relay is subsequently disconnected, the second relay R2 is not activated. The solenoid 5 is connected through a circuit 28 so that the auxiliary circuit 25 can keep the solenoid 5 energized.

Although the second auxiliary circuit 25 of the embodiment uses the second relay R2 and the second relay switch r2, when the solenoid 5 is energized and the air cylinder 2 is operated, the air cylinder 2 It is also possible to use a limit switch that switches in conjunction with actuation.

The present invention has the above-described configuration, and next, the connection and disconnection of the power extraction device 1 and the lifting and lowering operations of the cargo box 9 will be explained.

First, when the main operation switch S for lifting and lowering the cargo box is switched to the upper contact 17 position, and then the clutch pedal 19 is operated,
Since the limit switch LS interlocked with the clutch pedal 19 is connected, the first relay R1 is activated, and the first relay R
The first switch r1 for the first relay corresponding to 1 is switched to close.

As a result, the current from the power source B passes through the first operating circuit 20, energizes the solenoid 5 of the first switching valve 6, and switches the first switching valve 6 to the upper position.

When the first switching valve 6 is switched, the pressurized air in the air tank 3 flows into the base chamber of the air cylinder 20 through the air pipe 4, extending the air cylinder 2 and bringing the power extraction device 1 into contact with it.

On the other hand, the current from the power source B passes through the second operating circuit 21 and energizes the solenoid 12 of the second switching valve 14.
4 to the right position.

When the second switching valve 14 is switched, the hydraulic pump 7 is driven by the contact of the power take-off device 1 as described above, and the hydraulic oil discharged from the hydraulic pump 7 flows into the hydraulic cylinder 8 through the hydraulic piping 11. to extend the hydraulic cylinder 8 and raise the cargo box 9.

Incidentally, when the solenoid 5 is energized during the operation, the current from the power source B flows through the first operating circuit 20 and the circuit 28 to the second relay R2, and operates the second relay R2. Even if the second switch r2 for the second relay corresponding to the relay R2 is connected, and furthermore, the operation of the clutch pedal 19 is stopped and the limit switch LS, the first relay R1, and the first relay switch r1 are respectively disconnected, the main operation cannot be performed. When the switch S is connected to the upper contact 17, the auxiliary operation switch S' is closed, so the solenoid 5 of the first switching valve 6 is energized by the second auxiliary circuit 25.
and held through circuit 28.

To stop the cargo box 9 in the raised position as appropriate, press the operation switch S.
When the switch is switched to a neutral contact position (not shown), the energization to the solenoid 12 of the second switching valve 14 is cut off, the second switching valve 14 is switched to the neutral position, and the lifting of the cargo box 9 is stopped.

Furthermore, when the main operation switch S is switched to the neutral contact,
The sonoid 5 of the first switching valve 6 has an auxiliary operation switch S/
, a third switch r'1 for the first relay and a second switch r2 for the second relay are energized through the second auxiliary circuit 25 and the circuit 28, respectively, which are connected, and the power take-off device 1 is connected. It has become.

Next, to lower the cargo box 9 in the raised position, use the operation switch S.
When the switch is switched to the lower contact 22 position, the current from the power source B passes through the third operating circuit 23, energizes the solenoid 13 of the second switching valve 14, and switches the second switching valve 14 to the left position.

When the second switching valve 14 is switched, the hydraulic oil in the hydraulic cylinder 8 flows out into the oil tank through the hydraulic pipe 11, and the cargo box 9 is lowered.

Note that when the main operation switch S is switched to the lower contact 22, the auxiliary operation switch S' is disconnected, but the third switch B1 for the first relay and the second switch R2 for the second relay are turned off.
are in contact with each other, so the solenoid 5 of the first switching valve 6 is energized through the second auxiliary circuit 25 and the circuit 28, so the power extraction device 1 is not disconnected.

After that, when the power take-off device 1 is to be replaced, the clutch pedal 19 is operated with the operating switch S switched to the lower contact 22, and the third switch r'1 for the first relay is
When it is turned off, the auxiliary operation switch S' in the second auxiliary circuit 25 and the third switch r'1 for the first relay are cut off, so the power supply to the solenoid 5 of the first switching valve 60 is cut off. The first switching valve 6 is switched to the lower position.

When the first switching valve 6 is switched, the pressurized air in the air tank 3 flows through the air piping 4 into the front chamber of the air cylinder 20, and the air in the base chamber of the air cylinder 20 is released into the atmosphere, and the air cylinder 2 As it contracts, the power take-off device 1 is disconnected.

As described above, the present invention enables the raising and lowering of a cargo box and the connecting/disconnecting of a power take-off device to be operated with a single operation switch, thereby eliminating erroneous operations and ensuring safe and reliable control. Furthermore, the device is simple and very inexpensive.

[Brief explanation of drawings]

FIG. 1 is a partial view of a dump truck equipped with the device of the present invention;
FIG. 2 is an electrical system diagram of the present invention. In the figure, 1 is a power take-off device, 2 is an air cylinder redder, 3 is an air tank, 6 is a first switching valve, 1 is a hydraulic pump, 8 is a hydraulic cylinder for lifting and lowering a cargo box, 14 is a second switching valve, 1
9 is the clutch petal, 20 is the first operating circuit, 21 is the second
Operating circuit, 25 is auxiliary circuit, S is main operation switch, r1
is the first switch, r2 is the second switch, r'1 is the third switch, and S' is the auxiliary operation switch.

Claims (1)

[Claims] 1 Air from the air tank flows into the air cylinder at the first switching valve, which is switched by the operation of the solenoid.
The power extraction device is connected and disconnected by the flow, and a second switching valve, which is switched by the operation of a pair of solenoids, uses the hydraulic fluid of the hydraulic pump driven by the power from the power extraction device to raise and lower cargo boxes, etc. In an actuating device for a dump truck or the like that allows inflow and outflow into a hydraulic cylinder, one end is connected to the upper contact of the operation switch, the other end is connected to the solenoid of the first switching valve, and the clutch is connected in conjunction with the clutch valve midway,
a first operating circuit interposed with a first switch that is disconnected; a second operating circuit that has one end connected to the upper contact and the other end connected to one solenoid of the second switching valve; A second auxiliary switch that operates when the solenoid of the valve is energized, and an auxiliary operation switch that is disconnected when the operation switch is switched to the lower contact position and connected in other positions. It mainly consists of a circuit,
The second auxiliary circuit is an actuating device for a dump truck or the like that can maintain energization when the first actuating circuit de-energizes the solenoid of the first switching valve.