JPS6358449B2 - - 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 you move the fan door downwards,
This dump truck prevents the hook from disengaging from the locking pin due to the impact, 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 to the opening side, and the hook 01 is released from the locking pin 05. This causes the fan door 04 to fall.

In this state, if the sliding 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 rises, and the locking pin 05 disengages from the hook 01, so that the sliding door 04 falls due to its own weight. Therefore, there was a drawback 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, and includes a stopper piece provided at the rear lower part of the cargo box, and a guide pin provided on the mounting piece at the lower part of the sliding door. When the locking pin is fixed and the sliding door is moved downward around the lower hinge part, the locking pin and the stopper piece engage to prevent the engaging pin from coming off from the fitting hole of the holding piece. The purpose is to

(d) Means for Solving the Problems The present invention is characterized by rotating the hook that engages with the locking pin provided on the mounting piece at the bottom of the sliding door as the cargo box is raised and lowered. is opened and closed around the upper hinge part, while the locking pin is held between the holding piece provided on the cargo box side and having a fitting hole for receiving the locking pin, and the hook. In a tipper door opening/closing device for a dump truck in which the door can be moved downward by removing an upper hinge portion, a stopper piece rotatably supported by a shaft is provided at the rear lower part of the cargo box, and the above-mentioned mounting When a guide pin is fixed to the piece and the sliding door is moved downward around the locking pin supported by the holding piece, the locking pin and the stopper piece engage with each other due to the abutment of the guide pin. The present invention provides a safety device for a swing door opening/closing device for a dump truck, in which the stopper piece is formed with a pressing surface for upward rotation to a certain position.

(e) Example An example will be explained below with reference to the drawings. 1 is a cargo box that tilts rearward around a hinge part 3 at the rear end of a chassis frame 2; 4 is a cargo box provided at the upper part of the rear end of the cargo box 1; This sliding door swings around a removable upper hinge part 5, and a hook 7 is attached to the lower part of the sliding door 4, which fits into a holding piece 6 provided on the rear surface of the lower part of the cargo box 1. The locking pin 8 to be matched is attached to a pair of left and right mounting pieces 9, 9.
The holding piece 6, hook 7, and locking pin 8 constitute a lower hinge portion 10.

The holding piece 6 is formed with a fitting hole 11 that opens rearward, and the lower surface of the fitting hole 11 is substantially horizontal, and the upper surface thereof is inclined rearward and upward. The hook 7 is rotatably supported by a shaft 12 at the rear end of the bottom of the cargo box 1, and the tip of the hook 7 is disposed on the side of the one attachment piece 9 with the holding piece 6 as a boundary.

The mounting pieces 9, 9 are provided to protrude downward from the lower end of the sliding door 4, and have an L-shape in horizontal section. Reference numeral 13 designates a guide pin provided via the pair of left and right mounting pieces 9, 9, and is mounted above the locking pin 8.

14 is a stopper piece 15 rotatably supported between the mounting pieces 9, 9 at the rear lower part of the cargo box 1;
This stopper piece 14 rotates downward under its own weight,
The lower end 17 of the cutout hole 16 provided at the rear lower part of the cargo box 1 prevents downward rotation. Further, a pressing surface 18 is provided below the stopper piece 14, and is rotated upward to a position where the locking pin 8 and the stopper piece 14 are engaged by contact with the guide pin.

Reference numeral 19 denotes an operating arm 20 that is pivotably supported at the bottom of the cargo box 1 in front of the hook 7 so as to be able to swing back and forth.The operating arm 19 and the hook 7 are connected by a rod 23 that has a buffer tube 22 inside a spring 21 interposed therebetween. has been done.

A guide piece 24 guides the roller 25 at the tip of the operating arm 19, and is attached to the chassis frame 2 side.

Incidentally, 26 is a spring connected to the rod 23 side and the cargo box 1 side to spring the rod 23 rearward.

The present invention has the above-described structure, and its operation will now be described. First, when the cargo box 1 is raised, the roller 25 at the tip of the operating arm 19 separates from the guide piece 24, so the force of the spring 26 causes the rod 23 to move upward.
is pulled rearward, thereby disengaging the hook 7 from the locking pin 8. By the way, in this state, the locking pin 8 and the stopper piece 14 do not engage with each other, so the sliding door 4 swings rearward about the upper hinge portion 5, and the sliding door 14 is opened.

On the other hand, with the locking pin 8 being held between the holding piece 6 and the engaging claw 7, the upper hinge part 5 is removed and the fan door 4 is removed.
When the sliding door 4 is rotated approximately 180 degrees, it collides with the lower end of the cargo box 1 as shown in FIG. 4.

At this time, the attachment portion 9 of the locking pin 8 is attached to the collision portion 2.
A clockwise moment acts around 7,
This force acts on the tip of the hook 7 as a large force.

When this acting force is generated, the spring 21 in the buffer cylinder 22 is compressed and the distance between the operating arm 19 and the hook 7 is lengthened, so the hook 7 is rotated in a direction to disengage from the locking pin 8. However, at this time, the guide pin 13 touches the pressing surface 1 of the stopper piece 14.
8, the stopper piece 14 is rotated upward, and the locking pin 8 and the stopper piece 14 are engaged, so the locking pin 8 is rotated along the fitting hole 11.
This prevents the sliding door 4 from falling off.

Furthermore, if the sliding door 4 is moved downward around the lower hinge part 10 and the cargo box 1 is dumped in this state, the hook 7 will be rotated in the opening direction as shown in FIG. Since the locking pin 8 and the stopper piece 14 are engaged at this time as well, the locking pin does not come off from the fitting hole 11, and the sliding door 4 can be reliably prevented from falling.

Incidentally, in the present invention, the stopper piece 14 is attached between the attachment pieces 9, 9, but the locking pin 8 may be made to protrude from the attachment piece 9, and the stopper piece 14 may be attached to the outside of the attachment piece 9.

(f) Effects of the Invention As described above, the present invention provides a stopper piece having a pressing surface on the cargo box side, and a guide pin is fixed to the sliding door side, so that the sliding door can be guided when the sliding door is moved downward. By bringing the pin into contact with the pressing surface and rotating the stopper piece upward, the locking pin and the stopper piece are engaged with each other. This prevents the engaging pin from coming out of the fitting hole of the holding piece. This can reliably prevent the sliding door from falling.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing the overall view of the sliding door opening/closing device of the present invention, Fig. 2 is a sectional view when the opening of the cargo box is closed with the sliding door, and Fig. 3 is a rear view of Fig. 2. , 4th
The figure is a sectional view when the sliding door is moved downward, Figure 5 is a sectional view when the sliding door is moved downward to dump the cargo box, and Figures 6 and 7 are the conventional sliding door. It is a sectional view showing a switchgear. 1 is the packing box, 4 is the sliding door, 5 is the upper hinge part, 6
is a holding piece, 7 is a hook, 8 is a locking pin, 9 is a mounting piece, 10 is a lower hinge part, 11 is a fitting hole, 13
14 is a guide pin, 14 is a stopper piece, and 18 is a pressing surface.

Claims (1)

[Claims] 1 The hook that engages with the locking pin provided on the mounting piece at the bottom of the sliding door is rotated as the loading box is raised and lowered, and the sliding door is opened and closed around the upper hinge part. A dump truck in which the sliding door can be moved downward by removing the upper hinge part while the locking pin is held between the holding piece having a fitting hole for receiving the locking pin and the hook. In the fan door opening/closing device, a stopper piece rotatably supported by the shaft is provided at the rear lower part of the cargo box, and a guide pin is fixed to the mounting piece, and a locking pin supported by the holding piece is fixed to the mounting piece. A tipper for a dump truck, wherein the stopper piece has a pressing surface that rotates the stopper piece upwardly to a position where the locking pin and the stopper piece engage when the guide pin comes into contact with the guide pin when the door moves downward. Safety device in door opening/closing device.