KR101223960B1 - The multistage screw jack - Google Patents

Abstract

PURPOSE: A multistage screw jack is provided to prevent a buckling phenomenon as stress on deflection load is increased by increasing parts where a shaft and a boundary part of the shaft are overlapped by a reinforcing sleeve. CONSTITUTION: A multistage screw jack comprises a primary shaft(10), a secondary shaft(20), a third shaft(30), a secondary shaft sleeve(23), and a third shaft sleeve(33). The secondary shaft sleeve and the third shaft sleeve connect the bottom outer face of the secondary shaft and the top inner face of the primary shaft and the bottom outer face of the third shaft and the top inner face of the secondary shaft to prevent bending deflection when the secondary shaft and the third shaft are protruded to the hilt. An inward protrusion(26) is formed on the top inner face of the secondary sleeve so that the secondary shaft sleeve can support the secondary shaft inside the primary shaft in a state where the inward protrusion is hung on an outward protrusion(25) formed on the bottom outer face of the secondary shaft. An inward protrusion(36) is formed on the top inner face of the third shaft sleeve so that the third shaft sleeve can support the third shaft inside the secondary shaft in a state where the inward protrusion is hung on an outward protrusion(35) formed on the bottom outer face of the third shaft.

Description

Multistage screw jack {The multistage screw jack}

The present invention relates to a multi-stage screw jack, and more particularly, a plurality of hollow shafts are fitted in the same center, the rotational force is transmitted in the lead screw method so that the multi-stage screw unfolded in a multi-stage antenna type gearbox gearbox By coupling to the hollow shaft of the, it is possible to reduce the installation height of the multi-stage screw, and also to provide a wrench fastener for turning the hollow shaft with a manual wrench or an electric wrench to the outside of the gear box can be easily used in the field, Shafts are easy to add as many as needed, and worn or broken shafts are easily replaceable.These shafts relate to a multi-stage screw jack that has a built-in reinforcement sleeve and expands to compensate for flexural deformation and improve vertical accuracy. .

In general, a jack for transferring a heavy object from a low place to a high place mainly uses a hydraulic cylinder. However, while the hydraulic cylinder has the advantage of outputting a high load, there are many difficulties in maintenance and repair. In order to operate the hydraulic cylinder, there are many elements to be provided. There are a hydraulic unit for discharging the hydraulic oil, a cylinder, a valve for controlling the speed and pressure, a hydraulic hose and various connectors, and a hydraulic oil requiring periodic replacement. It is also a device that needs a lot of management such as oil leakage of hydraulic cylinder in long term use. Therefore, in the semiconductor and clean room processes requiring high cleanliness, the application of oil vapors due to leakage is a serious cause of failure.

So, we adopt screw type screw device that can replace hydraulic cylinder, but commercially produced screw is one-stage structure that simply connects screw and nut, so its own height is high, but its climbing height (transfer distance) is small. There is a limit to the situation.

In the prior patent No. 464620 and No. 199262 for the registration room has been proposed a multi-stage screw type transfer device. However, these methods simply screw the screw shaft in two stages so that it will appear. Therefore, it is not possible to increase the screw shaft more than two stages. Especially, if the screw shafts that are overlapped and lower in height are unfolded upward and the height is increased, the overlapping part of the boundary between the primary and secondary shafts is reduced, making them vulnerable to bending load. There was a technical problem.

In addition, Korean Patent No. 241595 and Korean Utility Model Publication No. 1989-16328 are multistage screw type feeders, but these methods are also susceptible to flexural loads due to the reduced overlap of the boundary between the primary and secondary shafts. Since the gear part directly connected to the motor has to be directly formed, there are technical disadvantages such as complicated structure.

The present invention has been developed in view of the conventional problems, an object of the present invention is to insert a plurality of hollow shafts in the same center, the rotational force is transmitted in a lead screw method, the multiple stages are unfolded in multiple stages of the antenna type By coupling the screw to the hollow shaft of the gearbox, the installation height of the multi-stage screw can be reduced, and a wrench fastener for turning the hollow shaft with a manual wrench or an electric wrench can be provided outside the gearbox for easy use in the field. The shafts can be easily expanded as many times as necessary, and worn or broken shafts can be easily replaced, and the shafts have a built-in reinforcement sleeve to be expanded to compensate for bending deformation and to increase vertical precision. In providing the jack.

To this end, the present invention is provided with a hollow shaft in which the upper and lower ends are supported by bearings in the portable gearbox, the hollow shaft penetrates the upper portion of the gearbox, and a worm wheel is provided in the gearbox on the outer circumferential surface of the hollow shaft. The worm wheel is meshed with a worm gear supported by a bearing, and one side of the worm gear is provided with a wrench fastener exposed to the side of the gearbox, so that the hollow shaft rotates by rotating the wrench fastener manually or by electric. The hollow shaft has a multi-stage screw, the multi-stage screw is a hollow primary shaft coupled to the hollow shaft to rotate in place; A hollow secondary shaft inserted into the hollow phase of the primary shaft and having a secondary shaft screw portion engaged with the primary shaft nut portion formed on the upper inner circumferential surface of the primary shaft; The third axis screw portion is inserted into the hollow inside of the secondary shaft, and the third axis screw portion engaged with the secondary shaft nut portion formed on the upper inner circumferential surface of the secondary shaft is formed on the outer circumferential surface of the hollow shaft to support the heavy object. A reinforcing sleeve is provided to connect a lower outer circumferential surface, an upper inner circumferential surface of the first axle, and a lower outer circumferential surface of the third axle, and an upper inner circumferential surface of the second axle, so that bending deformation is compensated for when the secondary and third axles protrude as much as possible. There is this.

According to the present invention, there is provided a gear box which is rotated by a manual handle or a power tool, and a hollow shaft is provided inside the gear box to be exposed to the outside. Therefore, when the multi-stage screw is fastened to the hollow shaft by a key and keyway coupling method, the rotational force can be easily transmitted, and assembly and disassembly are convenient. The hollow shaft is provided with a worm wheel on the outer circumferential surface and the worm wheel is meshed with the worm gear, the worm gear has a wrench fastener to be coupled to the wrench of the manual handle or power tool.

Therefore, if the hex wrench or square wrench of the manual handle or the power tool is inserted into the wrench fastener at the work site and rotates manually or by electric power, the multi-stage screw is operated while the hollow shaft is rotated. The multi-stage screw is composed of a hollow primary shaft coupled to the hollow shaft in a key and keyway manner, a hollow secondary shaft fitted to the primary shaft, and a hollow triaxial shaft fitted to the secondary shaft.

And the shafts are fitted with a reinforcement sleeve at the bottom. The reinforcement sleeve can be lowered because the shafts are superimposed with each other when the height is lowered, and the height of the shafts is increased when the axes are fully deployed and the height is increased, and the bottom length of the shaft is increased while being pulled out from the bottom of the corresponding shafts. Therefore, the portion where the axis and the boundary portion of the shaft overlap by the reinforcing sleeve is increased, so the stress against the bending load is increased, so that the buckling phenomenon does not occur, and the vertical precision is improved, so that shaking is suppressed.

1 is a perspective view of a screw jack of one embodiment of the present invention
Figure 2 is a cross-sectional plan view of a screw jack of one embodiment of the present invention
3 is a cross-sectional view of a multi-stage screw in one embodiment of the present invention
Figure 4 is a multi-stage screw operating state of one embodiment of the present invention

1 to 3, the screw jack of one embodiment of the present invention is provided with a portable gearbox 40 that is easy to move. Inside the gear box 40 is provided with a hollow shaft 41, the upper and lower ends are supported by a bearing 42, the hollow shaft 41 is penetrated to the upper portion of the gear box 40. The outer circumferential surface of the hollow shaft 41 is provided with a worm wheel 43 into the gearbox 40, the worm wheel 43 is meshed with the worm gear 44 supported by the bearing 46. And one side of the worm gear 44 is provided with a wrench fastener 45 exposed to the side of the gear box 40. The wrench fastening hole 45 is fitted with a hexagonal or square wrench 60, the wrench 60 is rotated by a manual handle 61 or a power tool 62.

The multi-stage screw is fastened to the hollow shaft 41 in a key and keyway manner. The multi-stage screw is composed of a hollow primary shaft 10, a hollow secondary shaft 20 and a hollow tertiary shaft 30 which are sequentially fitted. Another fourth and fifth axles may be inserted into the third axle 30 in order. The primary shaft 10 is provided with a space for accommodating the secondary shaft 20 therein, and the upper inner peripheral surface of the primary shaft nut portion 11 engaged with the secondary shaft screw portion 21 formed on the outer peripheral surface of the secondary shaft 20. ) Is formed.

The second axle 20 has a space for accommodating the third axle 30 therein, and an upper inner circumferential surface of the second axle 20 which is engaged with the third axle screw portion 31 formed on the outer circumferential surface of the third axle 30. 22) is formed. In addition, a reinforcement sleeve is provided below the secondary shaft 20 and the tertiary shaft 30 to reinforce the stress against the bending load.

The secondary shaft 20 is fitted with a hollow secondary shaft sleeve 23 on the lower outer periphery, the outward engaging jaw 25 is formed on the lower outer peripheral surface of the secondary shaft 20 and the secondary shaft sleeve 23 An inward locking jaw 26 is formed on the upper inner circumferential surface. In addition, the inside of the secondary shaft sleeve 23 is provided with a secondary shaft spring 24 that supports the lower end of the secondary shaft 20. In addition, the third axle 30 is fitted with a hollow third axle sleeve 33 on the lower outer circumference, the outward engaging jaw 35 is formed on the bottom outer peripheral surface of the third axle 30 and the third axle sleeve 33 Inwardly engaging jaw 36 is formed on the upper inner peripheral surface of the. In addition, the third axle sleeve 33 is provided with a third axle spring 34 that supports the lower end of the third axle 30. Reference numeral 32 is a third axis nut portion formed on the upper inner circumferential surface of the third axle 30, it is used to connect the four axle further, or to combine the plate for supporting the heavy material.

Screw jack of one embodiment of the present invention configured as described above is provided with a gearbox 40 having a hollow shaft 41 exposed to the outside. The hollow shaft 41 is attached to the multi-stage screw, as shown in Figure 3 when the primary shaft 10, the secondary shaft 20 and the tertiary shaft 30 is overlapped, the height is lowered. In this state, the wrench 60 of the manual handle 61 or the power tool 62 is inserted into the wrench fastening hole 45 of the side of the gearbox 40 and rotated through the worm gear 44 and the worm wheel 43. The shaft 41 is rotated. Since the hollow shaft 41 is connected to the primary shaft 10 in a key and keyway manner, the primary shaft 10 only rotates in place.

The third axle 30 is in a fixed state in contact with the weight 50, and the second axle 20 is rotated in place with the primary axle 10, so the secondary shaft nut portion 22 according to the principle of the lead screw The third axle screw portion 31 raises the weight 50 by rotating the third axle 30 while the linear motion is rotated. The secondary shaft nut portion 22 has a diameter smaller than that of the primary shaft nut portion 11, and the rotational friction force of the secondary shaft nut portion 31 with the primary shaft nut portion 11 and the secondary shaft screw portion 21 is reduced. Is less than Therefore, when the primary shaft 10 is rotated, the rotational force is transmitted to the secondary shaft 20 engaged with the primary shaft nut part 11, and the secondary shaft 20 rotates together with the primary shaft 10. The third axle 30 engaged with the secondary axle nut part 22 is raised.

As shown in FIG. 4, when the third axle 30 is raised as much as possible, the inward locking jaw 36 of the third axle sleeve 33 provided at the lower end of the third axle 30 is the second axle nut of the upper end of the second axle 20. The secondary axle 20 stops rotating while reaching the bottom of the part 22 and is no longer raised. From this time, the second axle 20 and the third axle 30 are connected to the heavy object 50 in a rotational stop state as a single column. Subsequently, when the primary shaft 10 is rotated, the secondary shaft screw portion 21 linearly moves while the primary shaft nut portion 11 is rotated according to the principle of the lead screw. Raising the axle 30 continues to lift the weight 50. When the inward locking jaw 26 formed at the upper end of the secondary shaft sleeve 23 contacts the primary shaft nut part 11 of the upper end of the primary shaft 10, the rotation of the primary shaft 10 is stopped and the weight ( 50) is raised as much as possible.

According to an embodiment of the present invention, when the secondary shaft 20 is raised, the secondary shaft sleeve 23 provided at the lower portion thereof extends into the primary shaft 10, thereby compensating for the stress on the bending load. In addition, the third axle 30 also extends to the inside of the second axle 20 so that the stress on the flexural load is compensated for, even if the second axle 20 and the third axle 30 protrude long. There is no In addition, when the first axle 10 is rotated in the reverse direction when the weight 50 is raised, the second axle 20 and the third axle 30 are lowered in the reverse order when they are raised to each sleeve 23, 33. Since the falling distance of the corresponding secondary shaft 20 and the third shaft 30 is restricted while the prepared secondary shaft spring 24 and the third shaft spring 34 are compressed, the effect of preventing wear and damage of the screw part due to excessive lowering have.

10: 1st axle 11: 1st axle nut part
20: 2 axle 21: 2 axle thread
22: secondary shaft nut 23: secondary shaft sleeve
24: 2 axle spring 30: 3 axle
31: 3 axle screw part 32: 3 axle nut part
33: 3 axle sleeve 34: 3 axle spring
40: gearbox 41: hollow shaft
42: bearing 43: worm wheel
44: worm gear 45: wrench fastener
46: bearing 50: heavy
60: wrench 61: manual handle
62: power tools

Claims (3)

delete The inside of the portable gear box 40 is provided with a hollow shaft 41, the upper and lower ends are supported by a bearing 42, the hollow shaft 41 is penetrated to the upper portion of the gear box 40, the hollow shaft The outer circumferential surface of the 41 is provided with a worm wheel 43 in the gearbox 40, the worm wheel 43 is engaged with the worm gear 44 supported by the bearing 46, one side of the worm gear 44 Is provided with a wrench fastener (45) exposed to the side of the gear box 40 to rotate the wrench fastener (45) by manual or electric drive so that the hollow shaft 41 is rotated; The hollow shaft 41 has a multi-stage screw, the multi-stage screw is a hollow primary shaft (10) coupled to the hollow shaft 41 to rotate in place; The hollow secondary shaft (10) which is inserted into the hollow inside of the primary shaft (10) and is engaged with the primary shaft nut portion (11) formed on the upper inner circumferential surface of the primary shaft (10) on the outer circumferential surface ( 20); It is inserted into the hollow inside of the secondary shaft 20, the third shaft screw portion 31 is formed on the outer circumferential surface and engaged with the secondary shaft nut portion 22 formed on the upper inner circumferential surface of the secondary shaft 20 to support the heavy object In the multi-stage screw jack composed of a hollow triaxial shaft (30),
Secondary axle sleeves 23 and 3 connecting the lower outer circumferential surface of the second axle 20 and the upper inner circumferential surface of the first axle 10 and the lower outer circumferential surface of the third axle 30 with the upper inner circumferential surface of the secondary axle 20. An axle sleeve 33 is provided, so that the bending deformation is compensated for when the second axle 20 and the third axle 30 protrude as much as possible,
The secondary shaft sleeve 23 has an inward protrusion 26 formed on the upper inner circumferential surface thereof so that the secondary shaft sleeve 23 is in the state of being caught by the outward protrusion 25 formed on the lower outer circumferential surface of the secondary shaft 20. 10 supports the secondary axle 20 therein,
The third axle sleeve 33 has an inward protrusion 36 formed on the upper inner circumferential surface thereof so that the third axle sleeve 33 is caught on the outward protrusion 35 formed on the lower outer circumferential surface of the third axle 30. (20) Multi-stage screw jack characterized in that to support the third axle inside. The method of claim 2,
A secondary shaft spring 24 is built in the secondary shaft sleeve 23 to elastically support the secondary shaft 20 when it is lowered to the maximum.
Multistage screw jack, characterized in that the third axle sleeve (33) inside the third axle spring (34) is built to support the elastically when the third axle (30) is lowered to the maximum.

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