JPS5826188Y2 - Loading platform opening/closing device in cargo handling lifting equipment - Google Patents

Description

[Detailed description of the invention] This invention relates to the improvement of a loading platform opening/closing device in a loading/unloading device that is installed on the loading platform of a truck, a loading box of a pan-type truck, etc., for loading and unloading cargo, and is particularly concerned with the improvement of the loading platform opening/closing device for loading and unloading cargo. A safety device is installed to prevent the loading platform from being accidentally raised.

In recent years, in order to load and unload cargo onto the loading platform of a lorry or the loading box of a pan-type lorry, a loading platform held almost horizontally is installed at the opening of the loading platform or loading box. 2. Description of the Related Art Equipment equipped with a cargo handling lifting device that moves up and down between the floor surface of a cargo box or the like and the road surface is being put into practical use.

The loading platform of this loading/unloading lifting device is designed to be stored standing up almost vertically except during cargo handling, but the loading platform itself is heavy and requires considerable effort to stand up manually. Since this requires labor, it is necessary to raise the cargo tray by rotating it using a hydraulic cylinder device, or to install a guide cam on the cargo platform or the cargo box side and an operating cam on the cargo receiving platform side to raise the cargo tray. There was one in which the loading platform was raised by an operating cam coming into contact with a guide cam when the platform was raised.

By the way, in the latter loading/unloading platform opening/closing device that uses a guide cam and an operating cam to raise and lower the loading platform when the loading platform is raised or lowered, it is necessary to prevent the guide cam and operating cam from coming into contact with each other during normal cargo handling. This operation had to be performed manually by the operator.

However, if the worker forgets to do this, or if the load hits the guide cam, operating cam, etc., the worker may not be aware that the guide cam and operating cam are in contact with each other, and the load may fall onto the loading platform. If the loading platform is raised with a worker or a worker on it, there is a risk that the loading platform will stand up and the cargo or the worker will fall down and be damaged.

This invention uses the above-mentioned guide cam and operating cam,
This loading platform opening/closing device is capable of opening and closing the loading platform at the same time as raising and lowering the loading platform, and is equipped with a safety device to prevent damage to cargo or workers as described above. This is a cargo handling lifting device in which a loading platform is movably provided at the lower end of a runner that is driven up and down along a pair of columns erected in parallel at a predetermined interval, and a guide cam is installed on the column side. is provided, and on the other hand, an operating cam is installed on the loading platform; The cam is pivotally connected to the cam so that contact or separation can be selected, and when the load receiving platform is raised or lowered, the ID cam and the operating cam come into contact with each other and the load receiving platform rises and falls to open and close due to the cam action. None, the actuating cam is always urged to rotate in a direction away from the guide cam, and a stopper that holds the actuating cam in a position of contact with the guide cam is automatically activated by raising the loading platform. This is because it is designed to be removable.

Hereinafter, this invention will be explained in detail based on the embodiments shown in the drawings.

Fig. 1 is an overall perspective view of a cargo handling lifting device that is attached to an opening at the rear of a cargo box of a bread-type truck. A pair of vertically installed columns, the column 1 is formed into a substantially C-shaped cross section with a longitudinal notch on one side of a hollow rectangular cross section, and a hydraulic cylinder device (not shown) is installed in the column 1. A runner 2 is provided which is driven and moves up and down along the column 1.

The runner 2 has a T-shaped cross section, and a plate-shaped part of the runner 2 is provided so as to protrude outward from the notched groove of the column 1, and a bracket 3 attached to the lower end of the runner 2 is provided.
A pair of connecting rods 5, 5 protruding from the base end of the cargo receiving platform 4 are pivotally connected by a pivot 6, so that the cargo receiving platform 4 can be raised and lowered.

When the loading platform 4 is laid down, the upper edges of the tips of the connecting rods 5, 5 come into contact with the lower edges of the plate-shaped portions of the runners 2, so that the loading platform 4 is held in a substantially horizontal state. When it is stood up, it is almost vertical.

While the loading platform 4 is held substantially horizontally, the loading platform 4 is moved from a raised position where the upper surface of the lower frame 7, which is attached to the same plane as the floor of the loading box, and the upper surface of the loading platform 4 are approximately on the same plane. stand 4
Loading and unloading of cargo is carried out by moving up and down to the lowered position where the lower surface touches the road surface.

In FIG. 1, the upper door 9, whose base end is pivoted to the upper frame 8 at the upper end of the opening, is rotated downward and hangs down almost vertically, and when the loading platform 4 is in the raised position, the loading platform 4 is By raising the opening, the opening is closed by the upper door 9 and the loading platform 4, and the closed state is maintained by the locking devices 10a and 10b.

Next, referring to FIGS. 2 to 4, the opening/closing device for the loading platform 4 will be explained. A cam surface 11a is formed along the inner side of one of the pair of columns 1 with its lower end inclined rearward. On the other hand, the base end of a plate-shaped actuating cam 12 is pivotally attached to the base end of the loading platform 4 inside the connecting rod 5 by a shaft 13.
The tip of the operating cam 12 is rotatable in the direction of coming into contact with and separating from the guide cam 11, and a rod-shaped locking piece 14 with a lower end cut out is protruding from the outer surface of the operating cam 12. Locking piece 1
A locking member 15 having a notch 4 fixed to the side surface of the connecting rod 5.
The actuating cam 12 is moved by contacting the loading platform 4.
It is substantially parallel to the upper surface, and rotation of the operating cam 12 in the counterclockwise direction in FIG. 4 is inhibited.

A rod-shaped contact member 16 with a circular cross section is welded to the upper end surface of the operating cam 12, so that when the operating cam 12 is rotated clockwise about the shaft 13 in FIG. As shown by the two-dot chain line, when the contact member 16 comes into contact with the loading platform 4, the actuating cam 12 stands up almost at right angles to the upper surface of the loading platform 4, and no further rotation is possible. Deterred.

The actuating cam 12 is connected to the shaft 13 by a pin 17 passing through the shaft 13 in the diametrical direction at its fitting portion, and the actuating cam 12 and the shaft 13 rotate integrally.

In addition, the shaft 13 is extended inward of the cargo receiving platform 4,
A torsion coil spring 18 is fitted and biased to rotate the shaft 13 clockwise in FIG.
The tip of the operating cam 12 is biased in a direction to always stand up, that is, in a direction in which the tip of the actuating cam 12 is moved away from the guide cam 11.

Note that the device that biases the actuating cam 12 to rotate is not limited to the above-described torsion coil spring 18, but may be a tension coil spring, a torsion bar, or the like.

Further, on the upper surface of the loading platform 4, there is provided a substantially triangular stopper 20 which is pivoted near the operating cam 12 with its base end deviated from the center of gravity by a shaft 19 perpendicular to the upper surface of the loading platform 4. The stopper 20 lowers the operating cam 12 against the elastic force of the torsion coil spring 18 so as to be substantially parallel to the upper surface of the loading platform 4, as shown by solid lines in FIGS. 2 to 4. Afterwards, when the loading platform 4 is rotated to the side, the lower surface of the stopper 20 comes into contact with the upper end of the contact member 16 provided on the upper end surface of the operating cam 12, and the rotation of the operating cam 12 is prevented. 2 or 4, when the stopper 20 is rotated toward the front of the loading platform 4, the operating cam 12
The actuating cam 12 is rotated about the shaft 13 by the elastic force of the torsion coil spring 18, and stands upright on the upper surface of the loading platform 4.

Next, to explain the operation of the loading platform opening/closing device of this invention constructed as described above, first, the loading platform 4 is lowered in an almost horizontally laid down state, and then the loading platform 4 is lowered as shown by the solid line in FIG. Then, the actuating cam 12 is rotated counterclockwise about the shaft 13 against the elastic force of the torsion coil spring 18 to lie down almost parallel to the upper surface of the loading platform 4, and the stopper 20 is As shown by the solid line in Figure 2,
By rotating it laterally around the shaft 19, the upper end of the contact member 16 provided on the upper end surface of the actuating cam 12 comes into contact with the lower surface of the stopper 20, and the actuating cam 12 is twisted and coiled. The elastic force of the spring 18 holds it in a substantially horizontal state.

In this state, when the hydraulic cylinder device is operated to raise the loading platform 4, the tip of the operating cam 12 comes into contact with the cam surface 11a of the guide cam 11, and is guided while sliding on the cam surface 11a. Since the locking member 15 fixed to the connecting rod 5 and the locking piece 14 protruding from the operating cam 12 are in contact with each other, the loading platform 4 is integrated with the operating cam 12. The runner 2 gradually rises as shown by the dashed-dotted line in FIG. becomes.

While the loading platform 4 is rising, the actuating cam 12 comes into contact with the cam surface i1a of the guide cam 11, so that the locking piece 14 and the locking member 15 are in contact with each other, so that the stopper 20 The stopper 20 is spaced apart from the contact member 16 provided on the upper end surface of the actuating cam 12, and as the loading platform 4 rises, the stopper 20 is pivoted away from the center of gravity, so that the shaft 19 is moved by its own weight. When the load receiving platform 4 is rotated about the center and stands up almost vertically, the stopper 20 is moved toward the operating cam 12 as shown by the two-dot chain line in FIG.
The rotation of the actuating cam 12 is no longer restricted.

Then, the actuating cam 12 tries to stand up against the cargo receiving platform 4 due to the elastic force of the torsion coil spring 18.
The tip of the operating cam 12 is connected to the cam surface 1 of the guide cam 11.
Since the actuating cam 12 is in contact with 1a, the actuating cam 12 does not stand up.

In this state, the loading platform 4 is pressed against the opening side, and the locking device 10a is closed.

By locking with 10b, the loading platform 4 is held in a closed state.

Next, after releasing the locking devices 10a and 10b, the hydraulic cylinder device is activated to lower the loading platform 4, which operates in the exact opposite manner to the above, causing the loading platform 4 to gradually fall down. As shown by the solid line in FIG. 5, when the load receiving platform 4 is further lowered and the tip of the operating cam 12 no longer contacts the guide cam 11, the operating cam 12 is stopped by the stopper 20 as described above. Since its rotation is not regulated, due to the elastic force of the torsion coil spring 18,
As shown by the solid line in FIG. 6, the actuating cam 12 is rotated to stand up against the loading platform 4, and the contact member 16 provided on the upper end surface of the operating cam 12 is held in contact with the loading platform 4. .

When moving up and down the loading platform 4 to load and unload cargo, the actuating cam 12 moves against the guide cam 1 as shown in FIG.
Since the loading platform 4 is held at a position where it does not come into contact with the loading platform 1, the loading platform 4 does not stand up, but is held almost horizontally and moves up and down.

In this embodiment, the rotation of the actuating cam 12 is released from the rotation restriction due to the weight of the stopper 20 when the loading platform 4 stands up; however, the present invention is not limited to the structure of this embodiment. In short, the stopper may be configured to automatically release the restriction on the rotation of the actuating cam when the cargo receiving platform is erected.

As described in detail above, the loading platform opening/closing device for the loading/unloading device according to this invention can lift, lower, open and close the loading platform by simply raising and lowering the loading platform, and is simple in structure and operation. , and its operation is reliable, and it also reliably prevents the danger of the loading platform inadvertently standing up while cargo or workers are placed on the loading platform, causing damage to the cargo or workers. can do.

That is, when the loading platform is raised to close it, the stopper that restricts the rotation of the operating cam automatically releases the restriction on the rotation of the operating cam as the loading platform rises. Next, when the loading platform is lowered, the operating cam is always held in a position where it does not contact the guide cam by the elastic force of the torsion coil spring, and is in a state where cargo can be loaded and unloaded. This is an extremely safe system in which the loading platform will not stand up even if the loading platform is raised unless the cam is lowered almost parallel to the loading platform and the stopper holds the cam in that state. It is excellent and also practically useful.

[Brief explanation of drawings]

The drawings show one embodiment of this invention. Fig. 1 is an overall perspective view of the cargo handling lifting device, Fig. 2 is an enlarged plan view of section A in Fig. 1, and Fig. 3 is a section (■) in Fig. 2. 4 is a left side view of FIG. 2, 5 is a side view showing the operation of the loading platform opening/closing device, and 6 is a side view showing the operation as a loading/unloading device. It is a diagram. 1...Column, 2...Runner, 4...
... Loading platform, 11 ... Guide cam, 12.
...Operating cam, 18...Torsion coil spring, 20...Stopper.

Claims (1)

[Scope of utility model registration request] In a cargo handling/elevating device in which a cargo receiving platform is provided in a vertically movable manner at the lower end of a runner that is driven up and down along a pair of columns erected in parallel at a predetermined interval, a guide cam is provided on the column side, and a guide cam is provided on the column side; An actuating cam is pivotally mounted on the cargo receiving platform so that it can be selectively brought into contact with or separated from the guide cam,
When the load receiving platform is raised and lowered, the guide cam and the operating cam come into contact with each other so that the load receiving platform rises and falls to open and close due to cam action, and the operating cam is rotated in a direction away from the guide cam. A load receiving platform opening/closing device characterized in that a stopper which is always energized and which holds a talking cam in a position of contact with the guide cam is provided so as to be automatically released when the load receiving platform is raised.