JPS646969B2 - - Google Patents

Description

[Detailed Description of the Invention] (a) Industrial Application Field The present invention involves holding the locking pin between a holding piece that receives the locking pin at the bottom of the sliding door and a hook, and in this state, the locking pin is centered. When the fan door is moved downward,
This dump truck prevents the hook from disengaging from the locking pin due to the impact at this time, and also prevents the door from falling even when the cargo box is dumped with the door moved downward. It is used in the field of safety devices for sliding door opening/closing devices.

(b) Prior Art Conventionally, as shown in FIG. 6, in a fan door opening/closing device in which a buffer cylinder 03 containing a spring is provided in the middle of a rod 02 between an operating arm (not shown) and a hook 01, If the upper hinge (not shown) is removed and the sliding door 04 is moved downward around the lower locking pin 05, the sliding door 04 will violently collide with the lower end of the cargo box 06 due to its own weight. However, a moment acts on the lower part of the sliding door 04 centering on the collision part 07, and a large force acts on the hook 01 in the opening direction.

At this time, the spring in the buffer cylinder 03 is compressed by the acting force, the distance between the operating arm and the hook 01 is lengthened, and the hook 01 is rotated toward the opening side, and the locking pin 05 is disengaged from the hook 01. This causes the fan door 04 to fall.

In this state, if the fan door 04 were to fall onto the feet of the worker, a serious accident would occur.

Furthermore, with the sliding door 04 moved downward, the cargo box 06
When dumped as shown in Figure 7, the hook is 0.
1 rotates as the cargo box 06 rises and engages the locking pin 05.
Since the engagement with the hook 01 is disengaged, the sliding door 04 falls due to its own weight. Therefore, there was a problem in that the heavy fan door 04 had to be lifted and installed.

(c) Problems to be Solved by the Invention The present invention has been made to solve the above-mentioned problems. By restricting the movement of the hook, the rotation of the hook is restricted,
To surely prevent the sliding door from falling even when the upper hinge of the sliding door is removed and the sliding door is moved downward or when a cargo box is dumped from this state.

(d) Means for Solving Problems The present invention is characterized in that the hook, which engages with the locking pin provided at the bottom of the sliding door, is rotated by an actuating device that rotates as the cargo box is raised and lowered. While the sliding door is automatically opened and closed around the upper hinge part, the locking pin is held between a holding piece provided on the cargo box side that receives the locking pin, and a hook. In a tipper door opening/closing device for a dump truck in which the door can be moved downward by removing the locking member, a locking member is fixed to an appropriate location on the actuating device, and an operating lever and the locking member are attached to the loading box side. A swinging member that engages and disengages from the member is rotatably provided, and the operating lever and the swinging member are connected via a link mechanism having a dead point mechanism.

(e) Example An example will be described below based on the drawings.

1 is a cargo box that tilts rearward around a hinge 3 at the rear end of the chassis frame 2; 4 is a sliding door that swings around a removable hinge 5 provided at the upper part of the rear end of the cargo box 1; A locking pin 8 having a circular cross section is provided at the bottom of the sliding door 4 to fit into a holding piece 6 provided on the rear surface of the bottom of the cargo box 4 and to engage a hook 7.

Next, the actuating device 9 that rotates the hook 7 by raising and lowering the cargo box 1 will be described. Reference numeral 10 is an actuating arm 11 that is pivoted at the bottom of the cargo box 1 in front of the hook 7 so as to be able to swing back and forth. A rod 14 is connected to the hook 7 and has a buffer tube 13 interposed inside a spring 12.

A guide piece 15 guides the roller 16 at the tip of the operating arm 10, and is attached to the chassis frame 2 side.

A spring 17 is connected to the rod 14 side and the cargo box 1 side and springs the rod 14 rearward.

A rectangular plate-shaped locking member 18 is fixed to the lock 14 of the actuating device 9, and a swinging member 19 that engages and disengages from the locking member 18 is rotatably provided at the bottom of the cargo box 1. be.

An operating lever 20 is rotatably provided at the lower part of the cargo box 1 in front of the swinging member 19, and the operating lever 20 and the swinging member 19 are connected via a link mechanism 22 having a dead point mechanism 21. The swinging member 19 is linked to the operation of the operating lever 20. This link mechanism 22 is composed of a dead point mechanism 21 and a rod 23 extending from the operating lever 20 to the swinging member 19.
The dead point mechanism 21 has a roughly doglegged base 2.
1a, a connecting portion 21b, and a bell crank 21c.

The present invention has the above-mentioned structure, and the operation will be explained next. As shown in FIG. 1, the operation lever 20
Dead point mechanism 21 that rotates counterclockwise.
The bell crank 21c also rotates counterclockwise, and the locked state of the dead point mechanism 21 is released.
The rotating piece 24 and the swinging member 19 are connected via the rod 23.
rotates clockwise, and the locking member 18 and the swinging member 1
The engagement with 9 is released.

However, when the cargo box 1 is raised, the operating arm 1
Since the roller 16 at the tip moves away from the guide piece 15, the rod 14 is pulled backward by the force of the spring 17, and the hook 7 and the locking pin 8 are disengaged, and the fan door 4 is released from the upper hinge. The sliding door 4 is opened by swinging rearward around the part 5.

Next, when the operating lever 20 is rotated clockwise as shown in FIG. Then, the swinging member 19 rotates counterclockwise, and the locking member 18 and the swinging member 19 engage with each other.

In this state, if you remove the hinge part 5 at the top of the fan door 4,
The sliding door 4 moves downward around the locking pin 8, and the sliding door 4 is opened.

As shown in FIG. 4, when the sliding door 4 rotates approximately 180 degrees, it collides with the end of the floorboard that constitutes the cargo box 1.
At this time, a clockwise moment acts on the mounting portion of the locking pin 8 with the collision tube 25 as the center, and this force acts on the tip of the hook 7 as a large force.

However, even if this acting force is generated, since the locking member 18 and the swinging member 19 are engaged, the hook 7
does not rotate, and the sliding door 4 is prevented from falling.

Furthermore, as shown in FIG. 5, even if the sliding door 4 is moved downward around the locking pin 8 and the cargo box 1 is dumped in this state, the locking member 18 and the swinging member 19 are not engaged. Since they are aligned, the hook 7 does not rotate and the swing door 4 is prevented from falling.

Furthermore, it is also possible to drain water from the load, such as earth and sand, which contains water. In this case as well, when the locking member 18 and the swinging member 19 are engaged and the cargo box 1 is slightly dumped, the hook is lifted. 7 does not rotate, the fan door 4 remains closed, and only moisture flows into the cargo box 1 and the fan door 4.
Water is drained from the gap between the holes and drained.

(f) Effects of the Invention As described above, the present invention provides a locking member in the actuating device that rotates the hook by raising and lowering the cargo box, and restricts the rotation of the hook by restricting the movement of the locking member. Therefore, even when the upper hinge of the sliding door is removed and the sliding door is moved downward, and even when the cargo box is dumped from this state, the sliding door is reliably prevented from falling, making it extremely safe.

Furthermore, it is possible to perform draining work for the person loading the cargo box.

[Brief explanation of the drawing]

FIG. 1 is an overall view of the device of the present invention showing a state in which the engagement between the locking member and the swinging member is released, FIG. 2 is a view taken in the direction of arrow A in FIG. 1, and FIG. FIG. 4 is an overall view of the device of the present invention showing the state in which the swinging member is engaged; FIG. 4 is a cross-sectional view showing the state when the sliding door is moved downward;
FIG. 5 is a state diagram when the sliding door is moved downward and then dumped, and FIGS. 6 and 7 are sectional views showing the conventional device. 1 is a packing box, 4 is a sliding door, 5 is a hinge part, 6 is a holding piece, 7 is a hook, 8 is a locking pin, 9 is an actuating device,
18 is a locking member, 19 is a swinging member, 20 is an operating lever, 21 is a dead point mechanism, and 22 is a link mechanism.

Claims (1)

[Claims] 1 An actuating device that rotates a hook that engages a locking pin provided at the bottom of the sliding door as the cargo box goes up and down automatically opens and closes the sliding door around the upper hinge part, while A tipping mechanism for a dump truck in which the tipping door can be moved downward by removing the upper hinge section while the locking pin is held between a holding piece provided on the side for receiving the locking pin and a hook. In the door opening/closing device, a locking member is fixed to an appropriate position of the actuating device, and an operating lever and a swinging member that engages and disengages from the locking member are rotatably provided on the cargo box side, and the operating device The lever and the swinging member are connected via a link mechanism having a dead point mechanism, and when the dead point mechanism is locked by rotating the operating lever, the swinging member and the locking member engage and lock the hook. When the rotation is regulated and the dead point mechanism is unlocked by rotation of the operating lever, the engagement between the swinging member and the locking member is released, allowing the hook to rotate freely. A safety device for the door opening/closing device of dump trucks.