A preload setting mechanism, SCARA robot forearm structure and robot

Abstract

The present invention provides a preload setting mechanism, a SCARA robot forearm structure and a robot. The preload setting mechanism comprises a shaft mounting plate, a support seat, an adjusting screw, a thrust block, a spring and a preload scale. The SCARA robot forearm structure comprises a forearm, a J3 axis and a J4 axis. The preload setting mechanism is respectively added to the J3 axis and the J4 axis. The compression amount of the spring is adjusted by rotating the adjusting screw, so that the spring generates a corresponding elastic force to act on the synchronous belt, and the size of the preload is read through the position of the thrust block on the preload scale to achieve the purpose of accurately setting the preload. The present invention can accurately set the preload of the synchronous belt drive during installation, maintenance and debugging, thereby improving the performance of the whole machine.

Description

Technical Field

[0001] The present invention relates to the technical field of robots, and in particular to a preload setting mechanism, a SCARA robot forearm structure and a robot. Background Art

[0002] The three-joint and four-joint SCARA robots are generally driven by synchronous belts, and the preload of the synchronous belt has a great influence on the transmission accuracy of the synchronous belt, so the preload will affect the performance of the whole machine. When the preload is less than the lower limit, the synchronous belt will jump, and when the preload is greater than the upper limit, abnormal noise or vibration will be generated and the life of the operating parts will be reduced. At present, when installing the synchronous belt, the manufacturers of SCARA robots use elastic parts to push and pull the force gauge in the direction parallel to the center line of the forearm to apply a relatively accurate preload, and the accuracy of this force depends to a large extent on the operator's experience level and operation method. If the direction deviates or the reading is inaccurate, it will cause the preload to have an error, thereby affecting the relevant accuracy and causing the performance of the whole machine to deteriorate. Another way is to measure the preload of the synchronous belt through an ultrasonic tensile gauge, and continuously adjust the preload of the synchronous belt according to the measurement results until the preload meets the requirements. This method requires continuous measurement and adjustment, and the process is complicated and inefficient. Summary of the invention

[0003] In view of the deficiencies of the prior art, the present invention can accurately set the preload force on the synchronous belt through a preload force setting mechanism without using other auxiliary equipment such as a dynamometer, and has convenient operation and strong stability.

[0004] To achieve the above object, the present invention adopts the following technical solution:

[0005] A preload force setting mechanism comprises a mounting plate, a support seat, an adjusting member, a pushing member, an elastic member and a preload force scale. The support seat is also provided with a guide member, which is connected to the support seat by interference fit, expansion or welding, or is manufactured integrally with the support seat. The elastic member and the pushing member pass through the guide member in sequence front and back, and the adjusting member is assembled on the support seat. The preload force scale can be installed on the mounting plate by gluing or screw connection, or the preload force scale and the mounting plate are manufactured integrally, the preload force scale is parallel to the guide member, and the scale on the preload force scale is pre-set according to the stiffness of the elastic member and the required preload force calculation, and the support seat is installed in cooperation with the mounting plate through the guide member; the axis of the preload force setting mechanism is colinear with the axis of the mounting plate, thereby ensuring that no additional torque is generated when the preload force is applied.

[0006] Furthermore, a threaded hole is provided on the support seat, and the threaded hole is installed in cooperation with the adjusting member. The adjusting member cooperates with the threaded hole and can move spirally in the threaded hole, while driving the pushing member to move along the guide member to cause the elastic member to produce compression deformation.

[0007] Furthermore, an axis guide hole is provided on the mounting plate, and the axis guide hole is installed in cooperation with the guide member, and a partial length of the guide member is inserted into the axis guide hole, thereby ensuring that the mounting plate can move along the direction of the guide member when subjected to the preload force applied by the elastic member.

[0008] Furthermore, one end of the pushing member contacts the adjusting member, and the other end contacts the elastic member.

[0009] Furthermore, a block guide hole is provided on the pushing member, and the block guide hole is installed in cooperation with the guide member.

[0010] Furthermore, the adjusting member is an adjusting structure that can be screwed in and out.

[0011] A SCARA robot forearm structure comprises a forearm, a J3 axis and a J4 axis, and also comprises a plurality of the above-mentioned preload setting mechanisms. The compression amount of an elastic member is adjusted by rotating an adjusting member in the preload setting mechanism, so that the elastic member generates a corresponding elastic force to act on the synchronous belts of the J3 axis and the J4 axis, and the size of the preload is read by the position of a pushing member on a preload scale, thereby achieving the purpose of accurately setting the preload.

[0012] Furthermore, the preload force setting mechanism includes a first preload force setting mechanism arranged on the J3 axis and a second preload force setting mechanism arranged on the J4 axis.

[0013] A robot comprises the robot forearm structure described in any one of the above items.

[0014] The beneficial effects of a preload setting mechanism, a SCARA robot forearm structure and a robot provided by the present invention are as follows: the present invention adjusts the compression amount of the elastic member by rotating the adjusting member in the preload setting mechanism, so that the elastic member generates a corresponding elastic force to act on the synchronous belt, and reads the size of the preload by the position of the pushing member on the preload scale to achieve the purpose of accurately setting the preload; during installation, maintenance and debugging, the preload setting mechanism can be used to accurately set the preload of the synchronous belt drive of the J3 axis and J4 axis of the robot forearm, thereby improving the performance of the whole machine; the structure is compact, the operation is convenient, safe and reliable, and the work efficiency during installation, maintenance and repair is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a schematic diagram of the structure of the preload setting mechanism of Example 1 of the present invention;

[0016] Figure 2 This is a schematic diagram of the support base structure of Example 1 of the present invention;

[0017] Figure 3 This is a schematic diagram of the structure of the mounting plate of Embodiment 1 of the present invention;

[0018] Figure 4 This is a schematic diagram of the thrust block structure of Example 1 of the present invention;

[0019] Figure 5 This is a schematic diagram of the structure of Example 2 of the present invention.

[0020] In the figure: 1, mounting plate; 2, spring; 3, thrust block; 4, adjusting screw; 5, support seat; 6, guide rod; 7, threaded hole; 8, shaft guide hole; 9, preload scale; 10, block guide hole; 11, forearm; 101, first mounting plate; 102, second mounting plate; 201, first spring; 202, second spring; 301, first thrust block; 302, second thrust block; 401, first adjusting screw; 402, second adjusting screw; 501, first support seat; 502, second support seat; 601, first guide rod; 602, second guide rod; 901, first preload scale; 902, second preload scale. DETAILED DESCRIPTION

[0021] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary persons in the art without creative work are within the scope of protection of the present invention.

[0022] Embodiment 1: A preload setting mechanism, see Figures 1 to 4 .

[0023] A preload setting mechanism comprises a mounting plate 1, a support seat 5, an adjusting screw 4, a thrust block 3, a spring 2 and a preload scale 9. A guide rod 6 is also provided on the support seat 5. The spring 2 and the thrust block 3 pass through the guide rod 6 in sequence front and back. The adjusting screw 4 is a hexagon socket screw and is assembled on the support seat 5. The preload scale 9 and the mounting plate 1 are an integrated structure and the preload scale 9 is parallel to the guide rod 6. The support seat 5 is installed in cooperation with the mounting plate 1 through the guide rod 6. The axis of the preload setting mechanism is colinear with the axis of the mounting plate 1, thereby ensuring that no additional torque is generated when the preload force is applied. The mounting plate 1 is fixed to the equipment used by screws.

[0024] The support seat 5 is provided with a threaded hole 7, which is installed in cooperation with the adjusting screw 4. The adjusting screw 4 cooperates with the threaded hole 7 and can move spirally in the threaded hole 7, while driving the thrust block 3 to move along the guide rod 6 so that the spring 2 is compressed and deformed.

[0025] There are two guide rods 6 symmetrically arranged on the upper end of the support base 5, and the threaded hole 7 is located in the middle of the two guide rods 6. The guide rod 6 is cylindrical and fixed to the support base 5 by welding.

[0026] The mounting plate 1 is provided with an axis guide hole 8, which is clearance-matched with the guide rod 6, and a part of the length of the guide rod 6 is inserted into the axis guide hole 8, thereby ensuring that the mounting plate 1 can move along the direction of the guide rod 6 when the preload force applied by the spring 2, and the position of the thrust block 3 on the preload force scale 9 indicates the size of the preload force.

[0027] One end of the thrust block 3 is in contact with the adjusting screw 4, and the other end is in contact with the spring 2; preferably, the cross section of the thrust block 3 is a trapezoid.

[0028] The thrust block 3 is provided with a block guide hole 10 , which is installed in cooperation with the guide rod 6 , and the thrust block 3 can move smoothly on the guide rod 6 through the block guide hole 10 .

[0029] In the above embodiment, when using, first loosen the set screws of the mounting plate 1. To prevent the mounting plate 1 from falling, do not completely unscrew the set screws of the mounting plate 1, and ensure that the mounting plate 1 is in a freely movable state. Rotate the adjusting screw 4 to make the adjusting screw 4 move spirally in the threaded hole 7, so that the other end of the adjusting screw 4 pushes the thrust block 3 to move on the guide rod 6, so that the thrust block 3 pushes the spring 2 to compress and deform to generate a preload, and pushes the mounting plate 1 to move, thereby driving the synchronous pulley installed on the mounting plate 1 to move in the tensioning direction, so that the synchronous belt generates a preload. The size of the preload is read by the position of the thrust block 3 on the preload scale 9. When the preload reaches the required appropriate value, the set screws of the mounting plate 1 can be tightened and fixed. In the above manner, the required preload can be accurately set for the synchronous belt.

[0030] To summarize, the working principle of the preload setting mechanism is as follows: the compression of the spring is adjusted by rotating the preload adjustment screw, so that the spring generates a corresponding elastic force to act on the synchronous belt, and the preload is read by the position of the thrust block on the preload scale to achieve the purpose of accurately setting the preload.

[0031] Example 2: A SCARA robot arm structure, see Figure 5 .

[0032] A SCARA robot forearm structure includes a forearm 11, a J3 axis and a J4 axis, wherein the J3 axis and the J4 axis are driven by a synchronous belt and are arranged on the forearm 11, and also includes a preload setting mechanism as described in Example 1, wherein the preload setting mechanism includes a first preload setting mechanism arranged on the J3 axis and a second preload setting mechanism arranged on the J4 axis, and the preload setting mechanism is used to accurately set the required preload for the synchronous belts of the J3 axis and the J4 axis.

[0033] The first preload force setting mechanism includes a first mounting plate 101, a first support seat 501, a first adjusting screw 401, a first thrust block 301, a first spring 201 and a first preload force scale 901. A first guide rod 601 is also provided on the first support seat 501. The first spring 201 and the first thrust block 301 pass through the first guide rod 601 in sequence from front to back. The first adjusting screw 401 is a hexagon socket screw and is assembled on the first support seat 501. The first preload force scale 901 and the first mounting plate 101 are an integrated structure and the first preload force scale 901 is parallel to the first guide rod 601. The first support seat 501 is installed in cooperation with the first mounting plate 101 through the first guide rod 601.

[0034] The second preload force setting mechanism includes a second mounting plate 102, a second support seat 502, a second adjusting screw 402, a second thrust block 302, a second spring 202 and a second preload force scale 902. A second guide rod 602 is also provided on the second support seat 502. The second spring 202 and the second thrust block 302 pass through the second guide rod 602 in sequence front and back. The second adjusting screw 402 is a hexagon socket screw and is assembled on the second support seat 502. The second preload force scale 902 and the second mounting plate 102 are an integrated structure and the first preload force scale 902 is parallel to the first guide rod 602. The second support seat 502 is installed in cooperation with the second mounting plate 102 through the second guide rod 602.

[0035] When setting the preload force of the synchronous belt of the J3 axis, first loosen the fixing screw of the first mounting plate 101. To prevent the first mounting plate 101 from falling, do not completely unscrew the fixing screw of the first mounting plate 101, and ensure that the first mounting plate 101 is in a freely movable state. Rotate the first adjusting screw 401 to make the first adjusting screw 401 move spirally in the first threaded hole, so that the other end of the first adjusting screw 401 pushes the first thrust block 301 to move on the first guide rod 601, thereby pushing the first spring 201 to compress and deform to generate preload force, and push the first mounting plate 101 to move, thereby driving the synchronous belt wheel installed on the first mounting plate 101 to move in the tensioning direction, so that the synchronous belt of the J3 axis generates preload force. The size of the preload force is read by the position of the first thrust block 301 on the first preload force scale 901. When the preload force reaches the required appropriate value, the fixing screw of the first mounting plate 101 can be tightened and fixed. In the above manner, the required preload force can be accurately set for the synchronous belt of the J3 axis.

[0036] When setting the preload force of the synchronous belt of the J4 axis, first loosen the fixing screw of the second mounting plate 102. To prevent the second mounting plate 102 from falling, do not completely unscrew the fixing screw of the second mounting plate 102, and ensure that the second mounting plate 102 is in a freely movable state. Rotate the second adjusting screw 402 to make the second adjusting screw 402 move spirally in the second threaded hole, so that the other end of the second adjusting screw 402 pushes the second thrust block 302 to move on the second guide rod 602, thereby pushing the second spring 202 to compress and deform to generate preload force, and push the second mounting plate 102 to move, thereby driving the synchronous belt wheel installed on the second mounting plate 102 to move in the tensioning direction, so that the synchronous belt of the J4 axis generates preload force. The size of the preload force is read by the position of the second thrust block 302 on the second preload force scale 902. When the preload force reaches the required appropriate value, the fixing screw of the second mounting plate 102 can be tightened and fixed. In the above manner, the required preload force can be accurately set for the synchronous belt of the J4 axis.

[0037] Embodiment 3: A robot.

[0038] A robot comprises the SCARA robot forearm structure described in Example 2.

[0039] The above description is only a preferred embodiment of the present invention, but the present invention should not be limited to the contents disclosed in the embodiment and the drawings, so any equivalent or modification completed without departing from the spirit disclosed in the present invention shall fall within the scope of protection of the present invention.

Claims

1. A preload setting mechanism, characterized in that: It includes a mounting plate, a support seat, an adjusting member, a pushing member and an elastic member, the support seat is also provided with a guide member, the elastic member and the pushing member pass through the guide member in sequence, the adjusting member is assembled on the support seat and connected with the pushing member, a preload scale is provided on the mounting plate, and the preload scale is parallel to the guide member, and the support seat is installed in cooperation with the mounting plate through the guide member; The preload force scale and the mounting plate are an integrated structure; The mounting plate is provided with a shaft guide hole, and the shaft guide hole is mounted in cooperation with the guide member.

2. The preload setting mechanism according to claim 1, characterized in that: The pushing member is provided with a block guide hole, and the block guide hole is installed in cooperation with the guide member.

3. The preload setting mechanism according to claim 1, characterized in that: One end of the pushing member contacts the adjusting member, and the other end contacts the elastic member.

4. The preload setting mechanism according to claim 1, characterized in that: The adjusting member is an adjusting structure that can be screwed in and out.

5. The preload setting mechanism according to claim 1, characterized in that: The elastic member is a spring.

6. The preload setting mechanism according to claim 1, characterized in that: The guide member is a guide rod.

7. A SCARA robot arm structure, comprising an arm, a J3 axis and a J4 axis, wherein the J3 axis and the J4 axis are driven by a synchronous belt and are arranged on the arm, characterized in that: It also includes multiple preload setting mechanisms as described in any one of claims 1-6, wherein the preload setting mechanisms include a first preload setting mechanism arranged on the J3 axis and a second preload setting mechanism arranged on the J4 axis, and the preload setting mechanisms are used to accurately set the required preload for the synchronous belts of the J3 axis and the J4 axis.

8. The SCARA robot arm structure as claimed in claim 7, characterized in that: The preload setting mechanism and the forearm are an integrated structure.

9. A robot, characterized in that: It comprises a robot forearm structure as described in any one of claims 7 to 8.

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