JPH0126523Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) The present invention relates to a lifting device that is attached to a vehicle for loading and unloading cargo, wheelchairs, etc., and is particularly suitable for being attached to the rear of a box-shaped vehicle. Regarding a lifting device.

(Prior Art) Conventionally, as shown in FIG. 4, this type of elevating device has an upper arm 2 and a lower arm 3 which are pivotally connected to a base box 1 fixed on the vehicle floor F. A side frame 4 is provided at the tip to form a parallelogram link mechanism, and a platform 5 on which cargo or a wheelchair is placed is attached to the lower end of the side frame 4. It has been proposed that a hydraulic cylinder 6 is provided between the upper support shafts.

(Problem to be solved by the invention) By the way, considering that the platform 5 is stored inside the rear door of the vehicle when not in use, the position of the base box 1 is slightly inside the rear end of the vehicle floor surface F. becomes. Therefore, in the configuration shown in Fig. 4, the upper arm 2 and lower arm 3
If the tip of the cylinder 6 is lowered, it will hit the vehicle floor surface F when the cylinder 6 becomes substantially horizontal, and the working angle α cannot be made very large. Therefore, in order to obtain the required lift amount of the platform, each arm length has to be increased.

(Means for solving the problem) In view of the above points, the present invention is designed to increase the working angle of the arm by devising the pivot point of the cylinder with respect to the parallel link mechanism having the upper arm and the lower arm. Furthermore, the present invention aims to provide a lifting device that can increase the lift amount of the platform.

The present invention provides a parallel link mechanism having an upper arm and a lower arm in the opening of the vehicle, a side frame is pivotally connected to the tips of the upper arm and the lower arm, and a platform is attached to the lower end of the side frame. At the same time, one end of the cylinder is pivotally connected to the side frame pivot point on the front end side of the upper arm, and the cylinder is mounted on the lower arm, which is located away from the vehicle side pivot point of the lower arm, or with the lower arm. The other end of the cylinder is pivotally connected to a small arm that rotates together, and the pivot point of the other end of the cylinder is positioned above the vehicle-side pivot point of the lower arm when the tip of the lower arm is lowered. This solves the above-mentioned conventional problems.

(Example) Hereinafter, an example of the elevating device according to the present invention will be described with reference to the drawings.

1 and 2, a base box 1 is installed and fixed on the floor surface F of a box-shaped vehicle 10, and an upper arm 2 and a lower arm 3 having the same length are pivotally connected thereto. A side frame 4 is pivotally attached to the tips of the upper arm 2 and lower arm 3 with pins 21 and 22. Such a structure is provided on both left and right sides of the rear opening of the box-shaped vehicle 10, and a platform 5 on which cargo or a wheelchair is placed is attached to the lower end of the left and right side frames 4. Here, the pivoting intervals of the upper arm 2 and the lower arm 3 with respect to the base box 1 and the pivoting intervals with respect to the side frame 4 are set to be equal, thereby forming a parallelogram link mechanism.

Now, the shaft body 2 to which the lower arm 3 is fixed
3 is pivotally supported by the base box 1, and a small arm 24 is further fixed to the shaft body 23 thereof. That is, the small arm 24 rotates together with the lower arm 3. One end (on the main body side) of the hydraulic cylinder 6 for rotating each arm 2, 3 is pivotally connected to a pivot point between the upper arm 2 and the side frame 4, that is, a pin 21,
The other end (piston rod side) of the cylinder 6 is pivotally attached to the tip of the small arm 24.

(Operation of the embodiment) In the above configuration, the platform 5 attached to the side frame 4 performs the following operations during cargo handling (elevating and lowering).
Since the upper arm 2 and the lower arm 3 form a parallel link, the horizontal position is always maintained.

If hydraulic pressure is not applied to the cylinder 6, the tips of the upper arm 2 and lower arm 3 will be in a lowered state due to their own weight (i.e., landing on the platform as shown by the imaginary lines in Figure 1). There is. At this time, the cylinder 6 is already in a contracted state, and the tip of the small arm 24 is at the second
It is in the raised position as shown. Therefore, the pivot point on the piston rod side of the cylinder 6 is located at the lower arm 3.
The cylinder 6 and the floor F are less likely to interfere with each other. That is, the cylinder 6 interferes after passing through the horizontal plane and tilting considerably. Therefore, the operating angle α of the arm can be increased, and the lift amount can be increased with the same arm length.

When hydraulic pressure is applied to the cylinder 6, the piston rod extends and transmits torque to both the upper arm 2 and the lower arm 3. As a result, the upper arm 2 and the lower arm rotate counterclockwise to move the piston rod toward the platform 5. maintains a horizontal position and rises to the level of the vehicle floor. The lifting and lowering movement of the platform 5 is used to load and unload cargo and wheelchairs.

FIG. 3 shows another embodiment of the invention. In this figure, instead of the small arm, a small arm portion 25 may be formed integrally with the lower arm 3 itself, and one end of the cylinder 6 may be pivotally connected to this small arm portion 25. Note that the other configurations may be the same as those of the above-mentioned embodiments.

(Effect of the invention) As explained above, according to the elevating device of the invention, a parallel link mechanism having an upper arm and a lower arm is provided in the opening of the vehicle, and In a configuration in which a side frame is pivotally connected to the side frame, and a platform is provided at the lower end of the side frame, one end of the cylinder is pivotally connected to the side frame pivot point on the tip side of the upper arm, and the lower arm is connected to the vehicle side of the lower arm. Since the other end of the cylinder is pivoted on the lower arm that is off the pivot point or on a small arm that rotates together with the lower arm, the cylinder can be attached to the upper arm and the lower arm. When the tip of the lower arm is lowered, the pivot point of the other end of the cylinder is located above the vehicle side pivot point of the lower arm, and the cylinder and the vehicle floor surface are less likely to interfere with each other. Therefore, the operating angle α of arm rotation can be increased, and the lift amount can be increased with the same arm length. Further, there is no need to provide a cylinder box or the like for storing the cylinder on the vehicle floor, and the device can be configured compactly.

[Brief explanation of the drawing]

Fig. 1 is a side view of an embodiment of the lifting device according to the present invention, Fig. 2 is a side view of the main part when the tip of each arm is lowered,
FIG. 3 is a side view of main parts showing another embodiment of the present invention;
FIG. 4 is a side view of the conventional example. 1...Base box, 2...Upper arm, 3...Lower arm, 4...Side frame, 5...Platform, 6...Hydraulic cylinder, 10...Box-shaped vehicle, 24...Small arm, 25
...Small arm section.

Claims (1)

[Scope of utility model registration request] A parallel link mechanism having an atsupa arm and a lower arm is provided in the opening of the vehicle, and the atsupa
A side frame is pivotally attached to the tip side of the arm and the lower arm, a platform is provided at the lower end of the side frame, and one end of a cylinder is pivotally attached to the pivot point of the side frame on the tip side of the upper arm.・The other end of the cylinder is pivotally connected to the lower arm that is located away from the vehicle-side pivot point of the arm, or to a small arm that rotates together with the lower arm, so that when the tip of the lower arm is lowered, A lifting device characterized in that a pivot point of the other end of the cylinder is located above a pivot point of the lower arm on the vehicle side.