JPS582085B2 - Dump Kayunadoniokel Aorido Kaihei Sousasouchi - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a door opening/closing device for electrically operating a rear door of a dump truck or the like.

A general dump truck is equipped with an opening/closing device that opens or locks the rear sliding door in relation to the ups and downs of the cargo box.

Furthermore, the opening/closing device has a structure that allows the sliding door to be always secured by manual operation when draining the cargo loaded in the cargo box, regardless of the ups and downs of the cargo box.

However, after draining the loaded material, when discharging the loaded material to a predetermined location, the operator forgets to release the manual operation for draining and dumps the cargo box to discharge the loaded material. There are many.

As a result, the loaded object is not ejected and the center of gravity moves backwards, causing the vehicle to roll backwards and damaging the hinges of the cargo box, which is extremely dangerous.

The present invention solves the above-mentioned drawbacks, and even if there is an error in the operation of the opening/closing device, if the cargo box is dumped at a predetermined angle or more, the sliding door will be automatically opened by electrical control. .

The embodiment will be described below with reference to the drawings. 1 is a driver's cab of a dump truck, 2 is a cargo box mounted on a subframe 3 of an automobile body, and the rear part is pivoted to the subframe 3 by a hinge pin 4.

Reference numeral 5 denotes a sliding door which is pivoted at the upper part of the rear end of the cargo box 2, and a horizontal shaft 7 is provided at the lower end thereof, which is engaged by a lashing claw 6 which is pivoted at the rear end of the bottom of the cargo box 2. be.

The lashing claw 6 is attached to the base end of the lashing claw 6 by moving it up and down.
When engaged, one end of the transmission link 8 is connected by a dead point method to prevent disengagement due to vibration etc., and the other end of the transmission link 8 is connected to a piston rod 10 of an air chamber device 9, which will be described later. It has been done.

The air chamber device 9 has a casing 11 fixed to the bottom of the cargo box 2, and a front chamber 1 inside the casing 11 with a diaphragm 12.
3 and a rear chamber 14, and the rear chamber 14 is provided with a piston rod 10 whose base end is fixed to the diaphragm 12 and whose other end protrudes from the casing 11, and a spring 15 that pushes the diaphragm 12 toward the front chamber 13 is installed inside. However, the front chamber 13 has a structure in which it communicates with an air tank 16 mounted on the vehicle body through an air pipe 17.

Reference numeral 18 denotes a solenoid valve interposed on the air pipe 17, which opens and closes the passage of the air pipe 17 by connecting and disconnecting current.

A first cord 20 from a DC power supply 19 is connected to the solenoid valve 18, and a first limit switch 21, which will be described later, is connected to the first cord 20 from the DC power supply 19 side by manual operation. , a main switch 22 for turning off the power is sequentially provided.

The first limit switch 21 is fixed to the subframe 3 so that it is closed when the cargo box 2 is in its lowest position and closed when it is in a dumped state.

The first cord 20 between the first limit switch 21 and the main switch 22 has a second cord 23 and a third cord 24.
are branched and connected to the solenoid valves 18 in parallel with the first cord 20.

The second cord 23 is led to the hinge pin 4 side, and a dump angle detection switch 26 is interposed at a position close to a cam 25 attached to the hinge pin 4.

The dump angle detection switch 26 is set so that the cargo box 2 is at a predetermined angle α.
If the dump is more than that, it will be connected, and the main switch 22 will be connected,
The solenoid valve 18 is made to be energized regardless of whether it is turned off or not.

Further, the cargo box 2 is cut off when it descends below a predetermined angle α.

The third cord 24 is led into the operator's cab 1 passing by the air chamber device 9, and next to the air chamber device 9 is a protrusion piece 27 attached to the tip of the piston rod 10.
A second limit switch 28 is installed in which the piston rod 10 is connected when the piston rod 10 is extended and disconnected when the piston rod 10 is contracted. A diode 30 is provided between the lamp 29 and the solenoid valve 18 so that current flows only to the solenoid valve 18 side.

The present invention has the above configuration, and its operation will be explained next.

When the cargo box 2 is at its lowest storage position, the first limit switch 21 is always turned off and the solenoid valve 1 is turned off.
8 is cut off.

Therefore, air is not supplied to the front chamber 13 of the air chamber device 9, and the piston rod 10 is pushed toward the front chamber 13 by the force of the spring 15, so that the transmission link 8
The lashing claw 6 engages with the horizontal shaft 7 via the latching claw 6 to secure the sliding door.

Now, in order to dump the cargo box 2 and discharge earth and sand, etc., first turn on the main switch 22, and when dumping the cargo box 2, the first limit switch 21 turns on, and the solenoid is connected through the first cord 20. The valve 18 is energized.

As a result, the air pipe 17 is opened, and the air in the air tank 16 is supplied to the front chamber 13 of the air chamber device 9.
5 and pushes it toward the rear chamber 14 side, whereby the lashing claw 6 is transferred via the piston rod 10 and the transmission link 8.
is rotated upward to release the engagement with the horizontal shaft 7.

As a result, the sliding door 5 opens and the earth and sand inside the cargo box 2 can be discharged.

Next, when the cargo box 2 is lowered, the first limit switch 21 is turned off at the lowest position, thereby cutting off the power supply to the solenoid valve 18, and the air pipe 17 is "closed".

As a result, the air in the front chamber 13 of the air chamber device 9 is released to the atmosphere, and the piston rod 10 is pushed toward the front chamber 13 by the force of the spring 15, and the horizontal shaft 7 is engaged with the lashing pawl 6 to open the fan door. 5 is tied up.

If you forget to turn the main switch 22 on and dump the cargo box 2, the first limit switch 21 will first turn on, and then the cargo box 2 will be dumped until the dump angle reaches the predetermined angle α or more. Then, the dump angle detection switch 26 of the second cord 23 is pressed by the cam 25 and becomes connected, and the solenoid valve 18 is energized through the second cord 23.

Accordingly, the air pipe 17 is opened, and the air in the air tank 16 is supplied to the air chamber device 9.
The engagement of the horizontal shaft 7 by the lashing pawl 6 is released, the sliding door opens, and the loaded object is discharged.

At the same time, the second limit switch 28 of the third cord 24 is connected due to the extension of the piston rod 10 of the air chamber device 9, the lamp 29 lights up, and the third cord 24 also energizes the solenoid valve 18. .

Next, when the cargo box 2 is lowered, the dump angle detection switch 26 is turned off when the dump angle of the cargo box 2 becomes less than the predetermined angle α, but the second limit switch 2 of the third cord 24
8 is in contact, the solenoid valve 18 is kept energized, and the locking claw 6 maintains the disengagement of the horizontal shaft 7.

Further, when the cargo box 2 is lowered and reaches the lowest position, the first
Limit switch 21 is disconnected and solenoid valve 1
8 is cut off, and the air pipe 17 becomes "closed".

Thereby, the horizontal shaft 7 engages with the lashing pawl 6.

At the same time, the piston rod 10 contracts, so the second limit switch 28 is turned off.

When draining soil, sand, etc., press the main switch 22.
If the dumper is dumped to the angle required for draining (approximately 10 degrees) with the water cut off, the horizontal shaft 7 is kept engaged with the lashing claws 6 because it is less than the predetermined angle α, without discharging dirt, etc. You can drain the water.

As described above, even if the main switch is operated incorrectly, the sliding door is opened when the dump angle of the cargo box exceeds a predetermined angle. There is no risk of damage at all.

[Brief explanation of the drawing]

Figure 1 is an overall view of a dump truck equipped with the present invention, Figure 2 is a circuit diagram of the present invention, Figures 3 and 4 are enlarged views of the dump angle detection switch, 2 is a cargo box, 5 is a sliding door, 6 is a lashing claw, 9 is an air chamber device, 16 is an air tank, 17 is an air pipe, 18 is a solenoid valve, 19 is a DC power supply, 21 is a first limit switch, 22 is a main switch, 26 is a dump angle detection switch, 28 is a second limit switch.

Claims (1)

[Claims] 1 Connect the lashing claw of the cargo box door and the air chamber device with a transmission link, connect the air chamber device and the air tank with an air pipe, and insert a solenoid valve in the middle of the air pipe to connect the solenoid valve. In a device that opens and closes the fan door by operating a valve, there is a main switch that can be switched inside the operator's cab, a dump angle detection switch that switches when the cargo box is tilted at a predetermined angle, and an air chamber device. A parallel circuit is constructed by arranging a second limit switch that is switched in relation to the undulation of the cargo box, and one end of this parallel circuit is connected to the first limit switch that is switched in relation to the ups and downs of the cargo box. A fan door opening/closing device for dump trucks etc. whose end is connected to a solenoid valve.