JPH036632Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a jack that is frequently used by carpenters at construction sites.

[Problems to be solved by conventional techniques and ideas]

With conventional jacks, the lifting object is placed on a rotatable support plate installed at the top of the lifting rod, so if a large load is applied to the jack, the lifting rod will not rotate smoothly and the handle will not operate smoothly. There was a drawback that it was not done.

[Means for solving problems]

The present invention solves these drawbacks, and its structure will be described in detail with reference to the accompanying drawings.

In a jack a in which a lifting rod 2 is raised and lowered by rotating a handle 1, a small diameter rod 3 is provided at the upper end of the lifting rod 2 to enable vertical movement and rotation of a set screw 9. 3, a ball receiving surface 5 is formed on the top surface of the small diameter rod 3, a ball 6 is placed on the ball receiving surface 5, and a coil spring 7 is supported by the spring receiving collar 4. A rotating tube 8 with a built-in interior is fitted onto the upper part of the lifting rod 2, a ball receiving surface 5' is formed on the lower surface of the top wall of the rotating tube 8, and a set screw 9 is provided on one side of the rotating tube 8. It is characterized by:

[Effect]

For example, when a push-up object 10 is placed on the upper surface of the rotating cylinder 8, the coil spring 7 is slightly compressed.

When the handle 1 is rotated, the lifting rod 2 is raised by the principle of a screw.

When a large load is applied to this rise, the coil spring 7 gradually contracts and presses the ball receiving surface 5' on the lower surface of the top wall of the rotating tube 8 against the ball 6 placed on the ball receiving surface 5 on the top surface of the small diameter rod 3. do.

In other words, the rotating tube 8 is connected to the ball 6 with respect to the lifting rod 2.
It is maintained in a freely rotatable state through the .

The interposition of this ball 6 facilitates the rotation of the rotating cylinder 8 and the smooth operation of the handle 1.

〔Example〕

Although the ball receiving surfaces 5, 5' in the drawings are shown to have a ∧ or ∨ shape in cross section, they may have any other shape as long as they can rotatably support the ball 6.

The coil spring 7 in the drawing prevents damage to the ball 6,
In addition, in order to cushion the push-up object 10, it is desirable that the spring be a relatively strong coil spring.

In the figure, numeral 11 is a slip prevention groove, 12 is a screw portion,
13 is a nut portion, 14 is a jack base cylinder, 15 is a base plate, 16 is a fixing screw hole, 17 is a support plate, and b is a fastener.

[Effect of idea]

Since the present invention is configured as described above, when a push-up object is placed on the upper surface of the rotating tube and the handle is rotated, the lifting rod rotates upward, and the push-up object is pushed up through the rotating tube. It turns out.

At this time, if the push-up object hits the ceiling and resistance is applied, the coil spring contracts, and the lower surface of the ceiling wall of the rotating tube comes into contact with the ball, causing it to rotate even though it is under load due to the interposition of the ball. This allows the lifting rod to rotate smoothly with respect to the moving tube.

Therefore, the turning operation of the handle becomes smooth as well, resulting in a jack that is very easy to turn.

At this time, since the coil spring is interposed, it is easy to attach the push-up object, and damage to the ball is also prevented.

Further, since the ball has a ball receiving surface on both the upper and lower bearing surfaces, the ball interposition effect is further improved.

In addition, the rotating barrel is formed in the small diameter rod part with a screw to prevent it from coming off while allowing the rotating barrel to rotate and move up and down, making it possible to carry the entire jack by holding the rotating barrel. It is an architectural jack that exhibits excellent practical effects.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention; FIG. 1 is a perspective view of the product, FIG. 2 is a front cross-sectional view, and FIG. 3 is a cross-sectional view of the main parts in use. a... Jacket, 1... Handle, 2... Elevating rod, 3... Small diameter rod, 4... Spring receiving tsuba, 5, 5'...
... Ball receiving surface, 6 ... Ball, 7 ... Coil spring, 8 ... Rotating cylinder, 9 ... Stop screw.

Claims (1)

[Scope of utility model registration request] In a jack where the lifting rod goes up and down by rotating the handle, a small diameter rod is installed at the top end of the lifting rod to enable the vertical movement and rotation of the set screw, and a spring receiving flange is installed at the top of this small diameter rod. A ball receiving surface is formed on the top surface of the small diameter rod, a ball is placed on the ball receiving surface, and a rotating tube containing a coil spring supported by the spring receiving collar is fitted onto the upper part of the lifting rod. A construction jack characterized in that a ball receiving surface is formed on the lower surface of the ceiling wall of the rotating tube, and a set screw is provided on one side of the rotating tube.