JPS6240833Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a rear sliding door opening/closing device for a freight vehicle, and in particular, when a lower hinge, top-opening type rear sliding door is opened to a hanging position, dirt and sand accumulated at the lower end of the rear sliding door. This is to ensure that the opening and closing operations of the rear sliding door will not be hindered by the loaded objects.

Although the applicant has already proposed a solution to this problem (Japanese Patent Application No. 56-214845), the present invention can also be sufficiently applied to the discharge of highly viscous loaded materials.

The present invention will be explained below with reference to examples. FIG. 1 shows a side view of an embodiment of the rear sliding door opening/closing device according to the present invention.

In this embodiment, the freight vehicle is configured as a dump truck, and a cargo box 3 is mounted on the frame of the dump truck via a subframe 1 so as to be tilted rearward along with a main girder 2 about a horizontal dump shaft 4. has been done. The rear sliding door 5 of the cargo box can be pivoted rearward from the rear end surface of the cargo box around a horizontal pivot 7 provided at the rear of the cargo box 3 by means of a bracket 6 fixed to it and a bracket 6' fixed to the rear end of the cargo box 3. supported.

A bell crank 8 is rotatably supported around a pivot 9 near the front side of the main girder 2, and a rearward arm 8
The roller 8B at the tip of A is arranged so as to contact the lower stopper 10, and the upper end of the upward arm 8C is pivotally connected to the tip of the operating lever 11 by a pin 12.

The operating lever 11 has a spring buffer cylinder 13 in the middle thereof, and is pulled rearward by a return spring 14 suspended from the bottom of the cargo box.

The rear end of the actuating lever 11 is pivotally connected to one end of a relay bell crank 16 whose center is pivotally supported to the main girder 2 by a pin 15 through a pin 17.
The other end of 6 is pivotally connected to the front end of the connecting link 18 by a pin 19. The other end of the connecting link 18 is connected to the main girder 2
The front end of the floating link 20A of the four-bar link 20 is pivoted by a pin 21, and the floating link 20A is
The rear end is pivotally connected to one end of the connecting link 22 by a pin 2, and the other end of the connecting link 22 is pivotally connected to another bracket 24 fixed to the rear fan door 5 by a pin 25.

According to the above-described configuration of the opening/closing link mechanism and the operating section connected thereto, when the cargo box 3 starts to tilt backward about the dump shaft 4, the roller 8B balances the traction force of the return spring 14 and stops at the initial stage. 10 is maintained and the rear fan door is kept closed. When the tilt angle of the cargo box exceeds a certain angle, the roller 8B separates from the stopper 10, and the operating lever 11 is pulled by the return spring 14 and moves to the right in FIG.
The floating link 20A of the four-bar linkage mechanism 20 moves to the left, the rear sliding door 5 is opened, and the rear sliding door 5 moves to a state where it hangs down beyond the angle at which it lines up with the bottom surface of the cargo box. When returning from the tilted state, the rear sliding door is closed by performing the operation opposite to the above.

By the way, when the rear sliding door 5 moves to a hanging state in conjunction with the tilting of the loading box 3, loaded materials such as earth and sand get caught between the rear sliding door 5 and the rear end of the loading box 3, making it difficult to open and close the rear sliding door. Operation may be impaired. The shielding member A for preventing this will be explained below with reference to FIGS. 2 and 3.

The shielding member A is formed of an arc-shaped cover body 2 that is fixed to the cargo box 3 through a bracket 26 above the pivot shaft 7 with a certain gap from the rear end of the cargo box 3 . This shielding member A includes a connecting link 22 between the left and right ends of the cargo box 3, and brackets 6, 6'.
It is arranged except for the area near the area.

Reference numeral 28 denotes a through hole, which is provided in the vicinity of the gap at the lower rear end of the packing box 3 where the shielding member A does not exist, that is, in the vicinity of the connecting link 22 and the brackets 6 and 6'.

Therefore, as the cargo box 3 tilts, the load such as earth and sand falls from the rear end of the cargo box 3 to the ground through the rear sliding door 5, but at this time, the arcuate cover body 27 protects the cargo box. 3 and the rear fan door 5 is covered, and earth and sand etc. slide down on this arcuate cover body 27.
Loaded materials such as earth and sand will not accumulate between the rear fan door 5 and the rear end of the cargo box 3.

Note that some of the earth and sand accumulated on the arc-shaped cover body 27 and the lower end of the rear fan door 5 is removed when the rear fan door 5 is raised and closed as the cargo box 3 is laid down. As a result of moving on the cover body 27, the rear sliding door 5
It will be scraped off at the bottom edge.

Therefore, the earth and sand move on the cover body 27 and enter the gap formed between the rear end of the packing box 3 and the cover body 27, and the through hole 2 formed at the rear end of the packing box opposite to the pivot part.
Falling through 8.

At this time, if the load is clay, etc., the rear fan door 5
When the lower end scrapes the load on the cover body 27 and compresses it between it and the rear end of the packing box 3, most of it falls through the gap formed between the cover body 27 and the rear end of the packing box 3, as described above. However, a part of it is pressed by the lower part of the rear fan door 5 and is discharged from the through hole 28.

That is, unlike the case where the through hole 28 is not formed, the loaded object that has no place to escape will not clog the pivot portion.

As described above, in the present invention, the shielding member is installed with a certain gap between it and the rear end of the packaging box, and a through hole is provided at the rear end of the packaging box facing the pivot part. When the rear sliding door is raised and closed, the loaded items accumulated on the shielding member fall reliably through the above-mentioned gap and through hole, and there is no problem in the opening and closing operation of the rear sliding door.

[Brief explanation of the drawing]

Fig. 1 is a side view of the rear sliding door opening/closing device according to the present invention, Fig. 2 is a rear view showing the main parts, and Fig. 3 is an enlarged vertical sectional view of the main parts. 3... Loading box, 4... Dump shaft, 5... Rear sliding door, 7... Pivot, 28... Through hole, A... Shielding member.

Claims (1)

[Scope of utility model registration request] In a freight vehicle in which a rear sliding door is pivotally supported at the lower part of a rear end of a cargo box so that the rear sliding door can be opened and closed, the cargo box has a certain gap from the rear end of the cargo box, and the rear sliding door is positioned above the rear end of the cargo box except for the pivot part. A rear sliding door opening/closing device for a freight vehicle, characterized in that a shielding member is installed and a through hole is formed at the rear end of the cargo box facing the pivot portion.