JPS61232934A - Safety device for rear dump door opening-closing device of damp truck - Google Patents

Abstract

PURPOSE:To prevent a rear dump door from falling even when a cargo box is dumped down by providing a stopping member on an operating device which rotates a hook by means of lifting up and down of said cargo box and restraining said stopping member from moving. CONSTITUTION:A stopping member 18 is fixed to the lock 14 of an operating device 9, and a swinging member 19 which is engaged and disengaged with this stopping member 18 is rotatably provided on the lower part of a cargo box 1. When an operating lever 20 is rotated clockwise, the bell-crank 21C of a dead point mechanism 21 is also rotated clockwise causing the dead point mechanism 21 to be in a locked condition, and a rotary member 24 and a swinging member 19 rotate counterclockwise via a rod 23, causing the stopping member 18 to be engaged with the swinging member 19.

Description

Detailed Description of the Invention (al. Industrial Field of Application) The present invention is characterized in that the locking pin is held between a hook and a holding piece that receives the locking pin at the bottom of the sliding door, and in this state, the locking pin is held at the center. When the sliding door was moved downward, (E'J) prevented the hook from disengaging from the locking pin, and the cargo box was dumped while the sliding door was moved downward. It is used in the field of safety devices for dump truck door opening/closing devices designed to prevent the door from falling even in the event of an accident.

(b) Conventional technology Conventionally, as shown in FIG. In the door opening/closing device,
If you remove the upper hinge (not shown) of the fan door and move the fan door (04) downward around the lower locking pin (05),
Due to the weight of the door (04), the door (04) becomes a cargo box (06).
The hook (01) violently collides with the lower end of the sliding door (04), and a moment acts on the lower part of the sliding door (04) centering around the collision part (07), resulting in a large force acting on the hook (01) in the opening direction.

At this time, the spring in the buffer cylinder (03) is compressed by the acting force, and the distance between the operating arm and the hook (01) becomes longer, and the hook (01) is rotated to the opening side, causing the locking pin to be rotated. (05) comes off the hook (01) and the fan door (
04) will fall.

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

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

[C] Problems to be Solved by the Invention The present invention has been made in order to solve the above-mentioned problems. By restricting the movement of the hook, the rotation of the hook is restricted, and even when the upper hinge of the sliding door is removed and the sliding door is moved downward, or when the cargo box is dumped from this state, the sliding door can be prevented from moving. This is to ensure that it does not fall.

(d3 Means for Solving the Problems) The present invention is characterized in that the hook that 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 fan door is automatically opened and closed around the upper hinge part, the upper hinge part is held between the hook and the holding piece provided on the cargo box side that receives the locking pin. In a tipper door opening/closing device for a dump truck that allows the door to be moved downward by being removed, a locking member is fixed to an appropriate location on the actuating device, and an operating lever and the locking member are provided on the cargo box side. A swinging member that engages and disengages is rotatably provided, and the operating lever and the swinging member are connected via a link mechanism having a dead point mechanism.

(el example Hereinafter, one embodiment will be described 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), and (4) is a removable hinge provided at the top of the rear end of the cargo box (1). A sliding door that swings around the sliding door (5), and a cargo box (4) at the bottom of this sliding door (4).
While fitting into the holding piece (6) provided on the rear surface of the bottom,
A locking pin (8) with a circular cross section is provided for engaging the hook (7).

Next, the actuating device (9) that rotates the hook (7) by lifting and lowering the cargo box (1) will be explained. αω is the hook (7)
At the bottom of the front cargo box (1), there is a pivot support (11) that can swing back and forth.
The actuating arm aω and the hook (7) are connected by a rod (14) in which a buffer tube (13) inside a spring (12) is interposed.

(15) is a guide piece that guides the roller (16) at the tip of the operating arm αω, and is attached to the chassis frame (2) side.

(17) is a spring that is connected to the rod (14) side and the cargo box (11 side) and springs the rod (14) rearward.

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

An operating lever (20) is rotatably provided at the bottom of the cargo box (11) in front of the swinging member (19), and the operating lever (20) and the swinging member (19) are connected to each other by a dead point mechanism. (21) through a link mechanism (22), and the swinging member (19) is interlocked with 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), and the dead point mechanism (21) is roughly shaped like a dogleg. The base of the shape (21a), the connecting part (
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, when the operating lever (20) is rotated counterclockwise, the bell crank (21C) of the dead point mechanism (21) is Rotate clockwise, the dead point mechanism (21) is unlocked, and the rod (23)
The rotating piece (24) and the swinging member (19) are rotated clockwise through the locking member (18) and the swinging member (19) are disengaged from each other.

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

Next, as shown in Fig. 3, when the operating lever (20) is rotated clockwise, the bell crank (21c) of the dead point mechanism (21) also rotates clockwise, and the dead point mechanism (21) is activated. In the locked state, the rotating piece (24) and the swinging member (19) rotate counterclockwise via the rod (23), 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 swing door (4) rotates approximately 180 degrees, it collides with the end of the floorboard that constitutes the cargo box (1).

At this time, the attachment part of the locking pin (8) is located at the collision part (25).
A moment acts in a clockwise direction around , and this force acts as a large force on the tip of the hook (7).

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

Furthermore, 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) Since the hook (7) is engaged with the swinging member (19), the hook (7) does not rotate.
The sliding door (4) is prevented from falling.

Furthermore, it is also possible to drain water from a load such as earth and sand, and in this case, the locking member (18) and the swinging member (19) are engaged in the same manner as described above to remove the cargo box (1). When the cargo box (1) and the door (4) are dumped a little, the hook (7) does not rotate, so the fan door (4) is kept closed, and only moisture is drained from the gap between the cargo box (1) and the fan door (4).

(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 also possible to drain the contents of 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. An overall view of the device of the present invention showing the state in which the swinging member is engaged. FIG. 4 is a sectional view showing the state when the sliding door is moved downward, and FIG. 5 is a cross-sectional view showing the state when the sliding door is moved downward. , a state diagram when dumped, and FIGS. 6 and 7 are sectional views showing the conventional device. (1) is the packing box, (4) is the sliding door, (5) is the 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. Applicant Kyokuto Kaihatsu Kogyo Co., Ltd. Figure 5

Claims (1)

[Claims] A hook that engages with a locking pin provided at the bottom of the fan door is rotated by an actuating device that rotates as the cargo box goes up and down, and the fan door is automatically opened and closed around the upper hinge part, while the door is automatically opened and closed on the upper hinge part. A swing door for a dump truck, in which the swing door can be moved downward by removing the upper hinge part while the locking pin is held between a holding piece and a hook that are provided to receive the locking pin. In the opening/closing device, a locking member is fixed to an appropriate location 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 lever and a 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 of the hook is restricted and the dead point mechanism is set to the unlocked state by rotation of the operation lever, the engagement between the swinging member and the locking member is released, and the rotation of the hook is freed. Features safety device for dump truck door opening/closing device.