JPH0630796Y2 - Fixed lift hydraulic lift device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a lift device, and more particularly to a constant lift hydraulic lift device.

[Prior Art] A conventional hydraulic lift device includes a flat base and a table movable relative to the base. A guide device is provided between the base and the table to guide the table so that the table can move in a direction perpendicular to the base while maintaining a parallel relationship with the base. The guide device is usually a scissor link or pantograph mechanism. An actuator, which is a hydraulic cylinder, is also provided between the base and the table so that the table can be moved with respect to the base.

[Problems to be Solved by the Invention] In such a conventional hydraulic lift device, when oil leakage occurs in the hydraulic cylinder, the table gradually descends.

Therefore, an object of the present invention is to provide a constant lift device that can prevent the table from lowering even if oil leaks in the hydraulic cylinder of the actuator.

[Means for Solving the Problem] An actuator for a fixed-lift lift device according to the present invention has one end pivotally attached to a base and the other end in rolling contact with a table to bring the table into a low position and a table in a high position. And a hydraulic cylinder for moving the operating arm between the inverted position and the standing position, the operating arm being substantially vertical to the base in the standing position. It stops at a position.

[Embodiment] FIGS. 1 to 3 show an embodiment of a constant lift hydraulic lift device according to the present invention. The constant lift hydraulic lift device of the present invention includes a base 1 which is a rectangular frame assembled by welding in a flat plate shape. Above the base 1, a rectangular table 2 provided parallel to the base 1 is provided.
A guide device 3 is provided between the base 1 and the table 2 to guide the table 2 so that the table 2 can move in a direction perpendicular to the base 1 while maintaining a parallel relationship with the base 1. ing.

In the illustrated embodiment, the guiding device 3 is a combination of two sets of links, each of which is formed by intersecting each other so as to be rotatable with respect to each other.
It is composed of two pantograph mechanisms. The first link 4 of each pantograph mechanism has a lower end pivotally attached to the base 1 by a pin 5, and an upper end via a roller 6 to the table 2.
Is in contact with. The second link 7 is about half the length of the first link 4, and the lower end is a pin 8 in the middle of the first link 4.
And the upper end is pivotally attached to the table 2 by a pin 9.

The constant lift hydraulic lift device is further provided between the base 1 and the table 2 and includes an operating device 10 for moving the table 2 with respect to the base 1. The actuating device 10 comprises a pair of first and second actuating arms 13 and 14 pivotally attached to the base 1 at one end by a pin 11 and rollingly in contact with the table 2 via a roller 12 at the other end. ing.

The upper ends of the first and second actuating arms 13 and 14 are connected to each other by a rod 15 so as to interlock with each other.
Therefore, the table 2 has two actuating arms 13 and 14
It is supported by and is extremely stable. First and second
The operating arms 13 and 14 of FIG. 1 rotate about the pin 11 to raise the table 2 to a low position (broken line in FIG. 1) and to raise the table 2 to a high position (solid line in FIG. 1). Can operate to and from position.

A hydraulic cylinder 16 is connected to the first actuating arm 13, and the first and second actuating arms 13 and 1 are connected to each other.
4 can be rotated between the above-mentioned inverted position and standing position. The hydraulic cylinder 16 is a double-acting type, and the tip of the plunger 17 is a pin 18 which serves as a first operating arm 13.
And the tail end of the cylinder 19 is attached to the base 1 by a pin 20.
Are connected by.

In the standing position shown by the solid line in FIG. 1, the first and second actuating arms 13 and 14 of the actuating device 10 have a line of action 21, which is a line connecting the pin and the center of the roller, perpendicular to the surface of the base 1. Very close to 22, but stopped at a slight overshoot. Therefore, the load of the table 2 is received by the substantially upright first and second operating arms 13 and 14, and the hydraulic cylinder 16 receives almost no load. Therefore, the chance of oil leakage of the hydraulic cylinder 16 is extremely small. Further, even when the hydraulic cylinder 16 expands or contracts to a certain extent due to oil leakage or the like, the slight change in the length hardly affects the change in the height of the table 2.

The base 1 is provided with stoppers 23 at the four corners so as to prevent the table 2 from further descending when the table 2 is at a low position (position indicated by a broken line).

The present invention is not limited to the above-mentioned embodiment. For example, the first and second actuating arms 13, 1
Even if the plungers 4 can be rotated synchronously about the pin 11 by the respective plungers, the initial purpose can be suitably achieved.

In addition, the first operating arm 1 that constitutes the operating device 10
3 is L-shaped or V-shaped, the distal end of the operating arm 13 is rotatably connected to the rod 15, and the rear end thereof is
An elbow portion that is connected to the plunger 17 via a pin 18 and forms the lowermost end intermediate between the front end portion and the rear end portion of the first operating arm 13 is pivoted to the base 1 via the pin 11. Even when worn, the initial purpose can be suitably achieved.

Furthermore, the first actuating arm 13 and the second actuating arm 14 are respectively configured in the L-shape or the V-shape,
It may be configured to be controlled and driven by a separate plunger rotatably connected to the base 1.

[Advantages of the Invention] The actuator of the constant lift hydraulic lift device of the present invention is pivotally attached to the base at one end and rollingly contacts the table at the other end to set the table in the low position and the table in the high position. Equipped with an operating arm that operates between the upright position and a hydraulic cylinder that moves the operating arm between the inverted position and the upright position, and the operating arm stops at a position that is substantially vertical to the base in the upright position. To do. Therefore, the load of the table is received by the substantially upright operating arm, and the hydraulic cylinder receives almost no load. Therefore, there is very little chance of oil leaking from the hydraulic cylinder, and even if the hydraulic cylinder expands or contracts slightly beyond the prescribed length due to oil leaks, etc., the slight change in length almost affects the change in table height. Instead, the table can be maintained in place.

[Brief description of drawings]

FIG. 1 is a side view showing a constant lift hydraulic lift device of the present invention,
FIG. 2 is a front view of the constant lift hydraulic lift device of FIG. 1, and FIG.
The drawing is a plan view of the constant-lift hydraulic lift device of FIG. 1 ... Base 2 ... Table 3 ... Guiding device 10 ... Actuating device 13 ... Actuating arm 16 ... Hydraulic cylinder

Claims (1)

[Scope of utility model registration request] 1. A flat plate-shaped base, a table, and a base provided between the base and the table, the table being parallel to the base while maintaining a parallel relationship with the base. A pantograph-type guide device for guiding so as to be movable in a right angle direction; and an operating device provided between the base and the table and moving the table with respect to the base, wherein the operating device is An operating arm that is pivotally attached to the base at one end and rolls into contact with the table at the other end and that operates between an inverted position that sets the table in a low position and an upright position that sets the table in a high position, A hydraulic cylinder is provided for moving the operating arm to the inverted position and the standing position, and the operating arm stops at a position substantially vertical to the base in the standing position. To Fixed lift hydraulic lift device.