SU979269A2 - Manually driven screw jack - Google Patents

Description

(54) SCREW SWITCH WITH MANUAL DRIVE

one

This invention relates to lifting mechanisms.

P6 main author. St. No. 737354 is known for a manually operated screw jack, comprising a housing, a retractable stem with a self-aligning nut, a screw and a ratchet cooperating with a pawl, the ratchet crown being made with a profiled, open annular protrusion with bevels jg on the flange side of the cap forming the cavity with a diameter smaller than a diameter the teeth of the ratchet and the width of the ratchet is greater than the thickness of the ratchet pawl, which is mounted in the flywheel, and the flywheel with (5 pawl mounted on the screw with the possibility of limited longitudinal movement tim and biased relative to the cap body 1.

The disadvantage of the known jack is relatively low reliability during operation.

The purpose of the invention is to increase the reliability of the jack during operation.

To achieve this goal, the jack is provided with a flywheel stopper in the form of a spring-loaded lever fixed on the housing so that it can be rotated in a vertical plane to interact with the flywheel end face.

FIG. 1 shows a screw jack, a longitudinal section; FIG. 2 shows section A-A in FIG. 1, in FIG. 3 is a view B in FIG. one; in fig. 4 - off position of the braking device 5a.

Screw jack consists of body 1, pull-out slit 2 with a cargo shaped head, fixed nut

3 interacting with screw 4. On the case there is a cover with a veneer, made in the form of a screw 5. On the screw

4 A flywheel 6 is mounted, spring-loaded with a spring 7 and held by a pin 8.

In the flywheel is installed 1lep ratchet dog 9 on the axis 10, spring-loaded spring 11 mounted on the axis 12.

On the case there is a lever 13 on the axis 14, with a spring 15 which is podruzhknn1niy1.

Screw jack works as follows.

When the flywheel is rotated in a clockwise direction, the rotation through the pin 8 is transmitted to the screw 4. The screw 4 interacts with the fixed nut 3, which gives the forward stem 2 to the forward stem 2. Pull-out rod 2 pushes the load, lifting the load.

At the same time, the ratchet pawl 9 snaps across the teeth of the ratchet 5. When the flywheel is refined to rotate, the pawl 9 under the action of the spring 11 drops the ac of the bottom of the teeth of the ratchet 5 and slows down the screw of the reverse rotation. Brake device is on.

Lowering the load is made by turning the flywheel 6 counterclockwise after the braking device is turned off by pressing the flywheel and moving it in the axial direction. Lever 13, which rests against the end of the flywheel 6, prevents this movement.

When the lever is pressed with 13 with a finger and the handwheel 6 is pressed, the lever 13 enters the cavity 7 of the flywheel and after loosening under the action of the spring 15, the lever rests against the surface b on which it slides as the flywheel rotates.

At the same time, the dog 9 is removed from the bed with the ratchet 5 and under the influence of the spring 11, the hooks drop into the groove and are held in this position by a profiled protrusion. The braking device is off.

Turning the handwheel 6 counterclockwise lowers the load.

The doggie 9 slides along the jtc surface without allowing an opportunity to engage the braking device.

The brake device is automatically activated when the handwheel is rotated b clockwise, while the dog 9 slides over the surface 3, comes to the level with the teeth of the ratchet 5 and under the influence of the spring 7 the flywheel returns to its original position, the dog 7 engages the ratchet 5 the brake the device is turned on; the lever 13 under the influence of the spring 14 also occupies the initial position, preventing the axial movement of the flywheel 6 when pressed on it. The invention will improve the reliability of operation of the jack.

Claims (1)

Invention Formula Screw jack with manual drive. By aut. St. No. 737354, characterized by the fact that, in order to increase its reliability in operation, it. equipped with a flywheel stopper in the form of a spring-loaded lever fixed on the housing so that it can be rotated in the vergic plane to interact with the end of the flywheel. Sources of information taken into account in the examination 1, USSR Author's Certificate No. 737354, cl. Bbb F 3 / O8, 1977 (prototype).