A motor screw clearance eliminating device with adjustable preload force

Abstract

A motor screw clearance elimination device with adjustable preload force comprises a screw, a first nut and a second nut, the first nut and the second nut are correspondingly assembled on the screw, and further comprises a first pressure block, a second pressure block, an elastic member and a connecting mechanism; the first pressure block is fixedly connected to the first nut, the second pressure block is fixedly connected to the second nut, the first pressure block and the second pressure block are connected via the connecting mechanism, the two ends of the elastic member abut against the first pressure block and the second pressure block respectively, the connection between the first pressure block and the second pressure block prevents the relative movement of the first nut and the second nut, the connection between the first pressure block and the second pressure block forms an extrusion on the elastic member, and the elastic force of the elastic member eliminates the gap between the first nut, the second nut and the screw. The present invention eliminates the gap between the screw and the nut by the method of elastic preload, and can conveniently adjust the preload force and replace the elastic member.

Description

Technical Field

[0001] The invention belongs to the field of mechanical transmission, and in particular relates to a motor lead screw clearance eliminating device with adjustable preload force. Background Art

[0002] The lead screw is a transmission component that converts rotary motion into linear motion. It is a very high-precision component that can accurately determine the coordinate position of the workbench, convert rotary motion into linear motion, and transmit a certain amount of power. Therefore, there are very high requirements in terms of accuracy, strength and wear resistance.

[0003] As the degree of precision becomes higher and higher, especially for motion control systems, the gap between the nut and the screw, and the gap caused by the wear of the nut after running for a period of time, will cause position error when the nut changes its direction of movement.

[0004] In existing situations, screw transmissions are often equipped with double nuts, but this can cause axial displacement or rotation of the nuts when the two nuts are pushed apart or pulled together.

[0005] Some use a double-nut gasket adjustment method, but the adjustment is very troublesome after using it for a period of time.

[0006] Furthermore, some methods of eliminating gaps by using elastic preload cannot adjust the preload during use. When the spring wears out and needs to be adjusted and replaced, the adjustment and replacement process is cumbersome, wastes work hours, increases production costs, and reduces production efficiency. Summary of the Invention

[0007] The present invention aims to provide a motor lead screw clearance eliminating device with adjustable preload force, so as to solve the technical problems of eliminating the lead screw nut clearance, conveniently adjusting the preload force and replacing the elastic member.

[0008] To achieve the above-mentioned purpose, the specific technical solution of the motor screw clearance elimination device with adjustable preload force of the present invention is as follows:

[0009] A motor screw gap elimination device with adjustable preload force includes a screw, a first nut and a second nut, the first nut and the second nut are correspondingly assembled on the screw, and also includes a first pressure block, a second pressure block, an elastic member and a connecting mechanism; the first pressure block is fixedly connected to the first nut, the second pressure block is fixedly connected to the second nut, the first pressure block and the second pressure block are connected by the connecting mechanism, the two ends of the elastic member are respectively abutted against the first pressure block and the second pressure block, the connection between the first pressure block and the second pressure block prevents the first nut and the second nut from moving relative to each other, the connection between the first pressure block and the second pressure block forms an extrusion on the elastic member, and the elastic force of the elastic member after being extruded eliminates the gap between the first nut, the second nut and the screw.

[0010] In order to make the connection between the first pressing block and the second pressing block tighter, a groove is provided at the upper end of the first pressing block, and one end of the connecting mechanism is fixed in the groove; a connecting block is provided at the upper end of the second pressing block, which extends toward the first pressing block and can be embedded in the groove of the first pressing block, and the other end of the connecting mechanism is connected to the connecting block.

[0011] In order to make the connection mechanism itself have an adjustment function, the connection mechanism is a pair of guide rail components with a certain contact stiffness and capable of relative movement.

[0012] Furthermore, the guide rail assembly includes a first guide rail and a second guide rail, the first guide rail is connected in the groove, and the second guide rail is connected to the connecting block, and the relative movement of the first guide rail and the second guide rail realizes the adjustment of the pressure of the elastic member.

[0013] In order to facilitate the adjustment of the preload force and replacement of the elastic member, a plurality of adjustment holes are provided on the outer side of the first pressure block at positions corresponding to the grooves. Bolts pass through the adjustment holes and abut against the first guide rail. The tightness of the guide rail assembly is adjusted by tightening the bolts. The relative position of the first guide rail and the second guide rail can be adjusted by loosening the bolts, and the position of the guide rail assembly can be fixed by tightening the bolts.

[0014] Furthermore, the guide rail assembly is a cross roller guide rail.

[0015] Furthermore, the elastic member is a spring.

[0016] In order to more stably place the elastic member, placement holes are provided at corresponding positions of the first pressing block and the second pressing block, and both ends of the elastic member abut against the placement holes.

[0017] In order to drive the screw rod through the motor module, one end of the screw rod is connected to the motor module. Beneficial effects

[0018] By setting up double nuts and elastic members between the nuts, elastic force is used to eliminate the gap between the nuts and the screw rod, thereby ensuring the accuracy of the screw rod in converting rotational motion into linear motion. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a structural schematic diagram of a motor screw clearance elimination device with adjustable preload force according to the present invention;

[0020] Figure 2 This is a structural schematic diagram of a motor screw clearance elimination device with adjustable preload force according to the present invention;

[0021] Figure 3 This is a partially enlarged view of a motor screw clearance elimination device with adjustable preload force according to the present invention;

[0022] Explanation of the marks in the figure: 100, screw rod; 200, first nut; 300, second nut; 400, first pressure block; 500, second pressure block; 600, elastic member; 700, connecting mechanism; 800, motor module; 401, groove; 402, adjustment hole; 501, connecting block; 502, placement hole; 601, spring; 710, guide rail assembly; 711, first guide rail; 712, second guide rail. DETAILED DESCRIPTION

[0023] In order to better understand the purpose, structure and function of the present invention, the following is a further detailed description of a motor screw clearance elimination device with adjustable preload force according to the present invention in conjunction with the accompanying drawings.

[0024] Implementation example:

[0025] like Figure 1-3 As shown, a motor screw gap elimination device with adjustable preload force, the screw 100 is connected to the motor module 800, the motor module 800 drives the screw 100 to rotate, and two nuts are equipped on the screw 100, namely the first nut 200 and the second nut 300, and two corresponding pressure blocks are set, the first pressure block 400 is a "┌" type, and the second pressure block 500 is a "┃" type. The two nuts are fixedly connected to the two pressure blocks by bolts respectively. When the two pressure blocks are connected, they cannot move relative to each other, that is, the two nuts cannot move relative to each other, thereby ensuring the integrity of the two nuts.

[0026] A groove 401 is provided at the upper end of the first pressing block 400, and a connecting block 501 is provided at the upper end of the second pressing block 500. The connecting block 501 is fixedly connected to the upper end of the second pressing block 500 by bolts. The connecting block 501 extends in the direction of the first pressing block 400. The size of the connecting block 501 is smaller than the groove 401 and can be embedded in the groove 401.

[0027] In order to achieve connection between the two pressure blocks with adjustable distance, this embodiment selects a cross roller guide as the connection mechanism 700, but is not limited to a cross roller guide. All connection mechanisms with certain rigid contact and relative movement are acceptable.

[0028] The first guide rail 711 of the cross roller guide rail is connected to the first pressure block 400 in the groove 401, and the second guide rail 712 is connected to the connecting block 501 at the top of the second pressure block 500. This embodiment uses two sets of cross roller guide rails to make the connection more stable.

[0029] Placement holes 502 are provided at corresponding positions of the two pressure blocks. In this embodiment, both ends of the spring 601 serving as the elastic member 600 are provided in the placement holes 502. The size of the placement holes 502 matches the size of the spring 601. The two pressure blocks are connected by the cross roller guide rail to squeeze the spring 601 and eliminate the gap between the nut and the screw rod 100 by elastic pre-tightening.

[0030] An adjustment hole 402 is provided on the outer side surface of the first pressure block 400, corresponding to the position of the first guide rail 711 of the cross roller guide in the groove 401. The bolt abuts against the first guide rail 711 of the cross roller guide through the adjustment hole 402. When the bolt is tightened, the first guide rail 711 and the second guide rail 712 are locked and cannot move relative to each other; when the bolt is loosened, the relative position between the first guide rail 711 and the second guide rail 712 can be adjusted, that is, the distance between the two pressure blocks is adjusted to achieve the effect of adjusting the elastic force of the spring 601.

[0031] When responding to the production needs of different products, the preload force can be adjusted by tightening the bolt in the adjustment hole 402, and the gap between the nut and the screw rod 100 can be adjusted. If the preload force obtained by adjusting the elastic force of the spring 601 cannot meet the production requirements, the spring 601 needs to be replaced. The purpose of replacing the spring 601 can also be achieved by controlling the position of the guide rail to increase the distance between the two pressure blocks.

[0032] During use, the motor module 800 is powered off, the bolts of the adjustment hole 402 are loosened, and the pressure block is pulled to adjust the preload force. If necessary, the pressure block is pulled to a sufficient distance to remove the spring 601 and replace it with a new spring 601. After adjusting the position of the pressure block, the bolts are tightened to lock the two guide rails of the cross roller guide rail, and the motor module 800 is restored to power.

[0033] It will be understood that the present invention is described by way of some embodiments, and it will be appreciated by those skilled in the art that various changes or equivalent substitutions may be made to these features and embodiments without departing from the spirit and scope of the present invention. In addition, under the teachings of the present invention, these features and embodiments may be modified to adapt to specific circumstances and materials without departing from the spirit and scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application are intended to be protected by the present invention.

Claims

1. A motor screw backlash elimination device with adjustable preload force, comprising a screw, a first nut and a second nut, wherein the first nut and the second nut are correspondingly assembled on the screw, characterized in that: The invention also includes a first pressure block, a second pressure block, an elastic member and a connecting mechanism; the first pressure block is fixedly connected to the first nut, the second pressure block is fixedly connected to the second nut, the first pressure block and the second pressure block are connected by the connecting mechanism, the two ends of the elastic member are respectively in contact with the first pressure block and the second pressure block, the connection between the first pressure block and the second pressure block prevents the first nut and the second nut from moving relative to each other, the connection between the first pressure block and the second pressure block forms an extrusion on the elastic member, and the elastic force of the elastic member after being squeezed eliminates the gap between the first nut, the second nut and the screw rod; A groove is provided at the upper end of the first pressing block, and one end of the connecting mechanism is fixed in the groove; A connecting block is provided at the upper end of the second pressing block, the connecting block extends toward the first pressing block and can be embedded in the groove of the first pressing block, and the other end of the connecting mechanism is connected to the connecting block; The connecting mechanism is a pair of guide rail assemblies having a certain contact stiffness and capable of relative movement; The guide rail assembly includes a first guide rail and a second guide rail, the first guide rail is connected to the groove, and the second guide rail is connected to the connecting block, and the relative movement of the first guide rail and the second guide rail realizes the adjustment of the pressure of the elastic member; A plurality of adjustment holes are provided on the outer surface of the first pressure block at positions corresponding to the grooves. Bolts pass through the adjustment holes and abut against the first guide rail. The tightness of the guide rail assembly can be adjusted by turning the bolts. The relative position of the first guide rail and the second guide rail can be adjusted by loosening the bolts, and the position of the guide rail assembly can be fixed by tightening the bolts.

2. The motor screw clearance eliminating device with adjustable preload force according to claim 1, characterized in that: The guide rail assembly is a cross roller guide rail.

3. The motor screw backlash elimination device with adjustable preload force according to claim 1, characterized in that: The elastic member is a spring.

4. The motor screw backlash elimination device with adjustable preload force according to claim 1, characterized in that: Accommodation holes are provided at corresponding positions of the first pressing block and the second pressing block, and both ends of the elastic member abut against the accommodation holes.

5. The motor screw backlash elimination device with adjustable preload force according to claim 1, characterized in that: One end of the screw rod is connected to the motor module.

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