JP2879759B2 - Side-runout prevention jack - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a manually operated screw jack.

[0002]

2. Description of the Related Art FIG. 4 is a perspective external view of a conventional screw type jack. FIG. 4 (a) shows a state of the jack 21 when the jack 21 is not used, and FIG. It is a figure which shows the state of the jack 21 when an object is lifted using.

In FIG. 4A, an inner cylinder 23 is lifted and housed in an outer cylinder 22 and inserted into a pin insertion hole 24 of the inner cylinder 23 so that the inner cylinder 23 does not slide downward due to gravity. The pin 25 is hooked on the upper end 22 a of the outer cylinder 22, and the screw shaft 26 with the handle is almost entirely screwed into the inner cylinder 23.

When an object (not shown) to which the outer cylinders 22 of a plurality of jacks 21 are usually mounted by the mounting bracket 27 is lifted by the jack 21, first, as shown in FIG. The inner cylinder 23 is slid downward so that the pin 2 is passed through the pin insertion hole 28 of the outer cylinder 22 through the pin insertion hole 24 of the inner cylinder 23.
5, the outer cylinder 22 and the inner cylinder 23 are fitted and fixed to each other. Thereafter, the object is lifted to a required position by rotating the screw shaft 26 by rotating the handle 29.

[0005]

FIG. 5 is a sectional view of the screw jack shown in FIG. 4, and FIG. 5 (a) is FIG. 4 (b).
5A is a sectional view taken along the line BB 'in FIG.
It is sectional drawing.

The inner cylinder 23 is slid downward, and the outer cylinder 22 and the inner cylinder 23 are mutually moved at the position where the pin insertion hole 28 of the outer cylinder 22 and the pin insertion hole 24 of the inner cylinder 23 coincide with each other. The operation of fitting and fixing is simpler than the operation of moving the screw shaft 26 up and down by rotating the handle 29, and
The outer cylinder 2 up to the height position before the load for lifting the object is applied
After the inner cylinder 23 is slid with respect to
Lifting an object by the rotation operation of is a very general operation and causes no problem.

However, here, the inner cylinder 23 with respect to the outer cylinder 22
Is impossible without a slight gap 30 between the outer cylinder 22 and the inner cylinder 23, but the existence of the gap 30 causes the wobble phenomenon of the entire jack 21 around the pin 25. Cause.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and to provide a jack in which the outer cylinder and the inner cylinder are automatically tightly and stably fixed automatically by a load, and the wobble phenomenon does not occur.

[0009]

In order to achieve the above object, the present invention provides an inner cylinder slidably disposed in an outer cylinder, and projects downward from the inner cylinder to vertically move with respect to the inner cylinder. A screw shaft is screwed into the inner cylinder so as to be movable in the direction, a leg is provided at a lower end of the screw shaft, and a pin is removably inserted into a pin insertion hole provided on each of the side surfaces of the outer cylinder and the inner cylinder. In the screw type jack, the pin insertion hole of the outer cylinder is formed larger than the pin insertion hole of the inner cylinder, and a part of the edge of the pin insertion hole of the outer cylinder is formed on the pin when a load is applied. It is characterized in that it is shaped so as to be brought into contact and to be moved laterally.

[0010]

FIG. 1 is an external view of a lateral shake prevention jack according to an embodiment of the present invention. In FIG. 1, an outer cylinder 2 and an inner cylinder 3 of an anti-sway jack 1 attached to a not-shown object at a plurality of places by screws or the like are formed in a rectangular cylinder shape. FIG.
A female screw (not shown) is attached to the
The upper end 5a of the screw shaft 5 to which is attached is screwed. A leg 6 is attached to the lower end 5b of the screw shaft 5 with a screw or the like so as to be slightly rotatable about the screw shaft 5 in a swinging manner.

In the inner cylinder 3, a circular pin insertion hole 8 into which the pin 7 is inserted is formed at a required height position at the center of the opposing surface.

At the tip 7a of the pin 7, the inserted pin 5
So that the stopper 9 does not come off due to vibration or the like.
Is mounted so as to be rotatable in the axial direction of the pin 7 by cutting off the tip 7 a of the pin 7. A bore 10 is attached at one end to the rear end 7 b of the pin 7, and the other end of the bore 10 is fixed to the outer cylinder 2.

FIG. 2 is a side view of the outer cylinder 2 and the inner cylinder 3 of the lateral shake prevention jack 1. Pin insertion holes 11 are formed on opposite sides of the outer cylinder 2 in plane symmetry, but the center position is not at the center of both sides of the outer cylinder 2 but as shown in FIG. It is formed as a circular hole eccentric to the pin insertion hole 8.

When a load is applied to the anti-lateral shake jack 1,
The pin 7 is guided by the edge of the pin insertion hole 11 of the eccentric outer cylinder 2 and moves from the position shown in FIG.
Move to the position shown in (b). As a result, the inner cylinder 3 moves rightward with respect to the outer cylinder 2, the right gap 12 is eliminated, and the inner cylinder 3 comes into close contact with the inner surface of the outer cylinder 2, and the inner cylinder 3 fluctuates with respect to the outer cylinder 2. Is prevented. Note that the outer cylinder 2 and the inner cylinder 3 may be cylindrical. However, the degree of prevention of the wobble phenomenon is somewhat inferior to that of the square tube type.

FIG. 3 is a side view of the outer cylinder 2 shown as another embodiment of the present invention. In this embodiment, the pin insertion holes 13 formed on the opposing surface of the outer cylinder 2 are symmetrical with each other. Are formed in a trapezoidal shape in which the opposite side becomes narrower from bottom to top. When a load is applied to the anti-vibration jack 1, the pin 7 moves in the direction of the arrow along the oblique side of the trapezoid that gradually narrows the pin insertion hole 13, whereby the inner cylinder 3 moves rightward with respect to the outer cylinder 2. The inner cylinder 3 moves close to the inner surface of the outer cylinder 2 by eliminating the right gap 12, and the phenomenon that the inner cylinder 3 fluctuates with respect to the outer cylinder 2 is prevented. Note that the pin insertion hole 13 may be triangular.

As described above, the pin insertion hole 11 formed in the outer cylinder 2 is punched with the center position deviated, or the pin insertion hole 13 is formed in a trapezoidal shape. Further, it is possible to provide an economical screw-type jack that does not require a complicated operation such as tightly fixing the outer cylinder 2 and the inner cylinder 3 with bolts or the like.

The anti-sway jack according to the present invention is provided with a mobile lightning evacuated shelter, a mobile toilet, a mobile warehouse, a mobile rest area, a mobile store, or the like having mobile wheels on an installation surface. It is particularly suitable for raising and lowering.

[0018]

As described above, according to the present invention,
The pin insertion hole of the outer cylinder is formed larger than the pin insertion hole of the inner cylinder, and a part of the edge of the pin insertion hole of the outer cylinder is moved laterally by contacting the pin when a load is applied. When the load is applied to the inner cylinder via the outer cylinder and the pin, the pin is guided by a part of the edge of the pin insertion hole of the outer cylinder, and moves in the lateral direction, so that the inner cylinder is guided. Since the cylinder moves laterally in the outer cylinder and comes into close contact with the inside of the outer cylinder, the outer cylinder can be stably fixed to the inner cylinder, and the occurrence of the wobble phenomenon can be eliminated.

[Brief description of the drawings]

FIG. 1 is a perspective external view of a lateral shake prevention jack according to an embodiment of the present invention.

FIG. 2 is a side view of the outer cylinder of the jack for preventing the lateral shake.

FIG. 3 is a side view of an outer cylinder of a lateral shake prevention jack according to another embodiment of the present invention.

FIG. 4 is a perspective external view of a conventional screw-type jack.

FIG. 5 is a cross-sectional view of the conventional screw jack shown in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Side-runout prevention jack 2 Outer cylinder 3 Inner cylinder 4 Handle 5 Screw shaft 5a Upper end 5b Lower end 6 Leg 7 Pin 7a Tip 7b Rear end 8 Pin insertion hole 9 Stopper 10 Hole 11 Pin insertion hole 12 Gap 13 Pin insertion hole

Claims (4)

(57) [Claims] 1. An inner cylinder is slidably disposed in an outer cylinder, and a screw shaft is screwed to the inner cylinder so as to project downward from the inner cylinder and move vertically with respect to the inner cylinder. In a screw jack in which a leg is provided at a lower end of the screw shaft and a pin is removably inserted into a pin insertion hole provided on each of the side surfaces of the outer cylinder and the inner cylinder, the pin insertion hole of the outer cylinder is inserted into the inner cylinder. It is formed so as to be larger than the pin insertion hole of the cylinder, and a part of the edge of the pin insertion hole of the outer cylinder is shaped so as to abut on the pin and move laterally when a load is applied. A jack that prevents sideways swing. 2. The anti-lateral shake jack according to claim 1, wherein the pin insertion hole of the outer cylinder has a circular shape and is provided at a position eccentric with respect to the center of the side surface of the outer cylinder. 3. The anti-vibration jack according to claim 1, wherein the pin insertion hole of the outer cylinder is trapezoidal or triangular. 4. The anti-vibration jack according to claim 1, wherein both the outer cylinder and the inner cylinder are formed in a rectangular cylinder shape.