Flexible fine positioning mechanism for switching welding fixture

Abstract

The invention discloses a welding fixture switching flexible fine positioning mechanism, and relates to the field of workpiece machining, the welding fixture switching flexible fine positioning mechanism comprises a fixture, a ground positioning mechanism is mounted below the fixture, a fixture wheel is fixedly arranged below the fixture, and the height of the fixture wheel is lower than that of the ground positioning mechanism; the ground positioning mechanism comprises a base BASE plate, a plurality of Z-direction air cylinders, a plurality of X-direction air cylinders and a Z-direction height adjusting mechanism, the X-direction air cylinders are used for driving the Z-direction height adjusting mechanism to slide in the X direction, the outer walls of the Z-direction air cylinders are fixedly connected with air cylinder connecting plates, and the lower surfaces of the air cylinder connecting plates are installed on the upper surface of the base BASE plate. Through Z-direction lifting of the fixture, sliding of the Z-direction height adjusting cushion block and Z-direction falling, accurate positioning of the switching fixture in the X direction, the Y direction and the Z direction is achieved, the positioning accuracy of fixture switching is guaranteed, repeated positioning accuracy guarantee of workpiece grabbing and welding of a robot is facilitated, and then welding quality stability or part grabbing consistency is guaranteed.

Description

Technical Field

[0001] This application relates to the field of workpiece processing technology, and in particular to a flexible precision positioning mechanism for switching welding fixtures. Background Technology

[0002] The two most common flexible switching methods for the loading port fixtures of multi-model automated welding production lines are: switching by lifting the fixtures with a forklift (or power lift vehicle) and switching by manually pushing the fixtures.

[0003] However, using a forklift for switching requires a separate forklift vehicle, and the repeated lifting and lowering of the gripper by the forklift can affect the accuracy of the gripper and the deformation of the base plate. Using manual force to push the gripper for switching is limited by the precision requirements of the welding or gripping of the robot at the gripper work position. It is necessary to lift the gripper wheels off the ground to avoid precision defects caused by uneven gripper wheels. The common mode is that there is a ramp angle at the gripper landing point, which requires one or more people to use great force to push in a "charge" style to achieve the purpose of lifting the gripper wheels off the ground. This method of operation is very labor-intensive and does not meet the requirements of easy operation. Summary of the Invention

[0004] The purpose of this invention is to provide a flexible precision positioning mechanism for switching welding fixtures, which at least solves one of the technical problems of the repeated lifting and lowering of fixtures by forklifts affecting the accuracy of the fixtures and the deformation of the base plate, and the use of manual force to push the fixture switching, which is limited by the accuracy requirements of the welding or gripping of the robot at the fixture work position and does not meet the requirements of lightweight operation.

[0005] This invention provides the following solution:

[0006] According to one aspect of the present invention, a flexible precision positioning mechanism for switching welding fixtures is provided, comprising a fixture, a ground positioning mechanism mounted below the fixture, a fixture wheel fixedly disposed below the fixture, and the height of the fixture wheel being lower than that of the ground positioning mechanism, the ground positioning mechanism comprising a base plate, a plurality of Z-axis cylinders, a plurality of X-axis cylinders and a Z-axis height adjustment mechanism, the X-axis cylinders being used to drive the Z-axis height adjustment mechanism to slide along the X direction, a cylinder connecting plate being fixedly connected to the outer wall of the Z-axis cylinder, the lower surface of the cylinder connecting plate being mounted on the upper surface of the base plate, and a positioning execution mechanism being fixedly mounted on the driving end of the Z-axis cylinder.

[0007] Furthermore, the positioning actuator includes multiple sets of positioning blocks and multiple sets of positioning pins, and cylinder connectors are fixedly connected inside the positioning blocks and positioning pins. The cylinder connectors are installed on the drive end of the Z-axis cylinder.

[0008] Furthermore, a clamp bottom BASE plate is fixedly connected to the bottom of the clamp, and multiple clamp support blocks are provided inside the clamp bottom BASE plate, with each of the multiple clamp support blocks corresponding to a set of positioning blocks.

[0009] Furthermore, the bottom BASE plate of the fixture is provided with multiple fixture positioning pin sleeves inside, and the multiple fixture positioning pin sleeves correspond one-to-one with multiple sets of positioning pins.

[0010] Furthermore, the Z-axis height adjustment mechanism includes a Z-axis height adjustment pad and a Z-axis height adjustment pad connecting shaft. The two ends of the Z-axis height adjustment pad connecting shaft are fixedly connected to the inside of the Z-axis height adjustment pad. The inside of the Z-axis height adjustment pad has multiple interconnected holes.

[0011] Furthermore, the ground positioning mechanism is divided into left and right side structures, and the distance between the left and right side structures can be adaptively adjusted according to the size of the clamp.

[0012] Furthermore, a clamp guide plate is provided at the bottom of the clamp, and a plurality of clamp entry and exit guide wheels are slidably connected to the outer wall of the clamp guide plate. The clamp entry and exit guide wheels are fixedly connected to the outer wall of the base plate.

[0013] Furthermore, a clamp positioning limit block and a positioning sensor are fixedly connected to the upper outer wall of the base plate, and the clamp positioning limit block and the positioning sensor are located on the same horizontal line.

[0014] Furthermore, the cylinder connecting plate is detachably connected to the base plate via bolts, and the cylinder connecting piece has a groove inside, the shape and size of which are adapted to the drive end of the Z-axis cylinder.

[0015] A method for operating a welding fixture switching flexible precision positioning mechanism, used in any one of claims 1-9, comprising:

[0016] S1. Push the fixture along the preset path, so that the fixture guide plate at the bottom of the fixture slides under the guidance of the fixture entry and exit guide wheels fixed on the base BASE plate until the fixture contacts the fixture position limit block and is mechanically limited. At the same time, the position sensor detects that the fixture has reached the preset position and sends a position signal to the external control system.

[0017] S2. After receiving the positioning signal, multiple Z-axis cylinders are activated, causing their drive ends to move upward. Through the cylinder connector, multiple sets of positioning blocks and multiple sets of positioning pins in the positioning actuator rise synchronously, further causing the positioning blocks to contact and lift the fixture support blocks in the bottom BASE plate of the fixture. At this time, the positioning pins are inserted into the corresponding fixture positioning pin sleeves in the bottom BASE plate of the fixture, thereby lifting the entire fixture and causing the fixture wheels below it to leave the ground.

[0018] S3. After the fixture is lifted, multiple X-axis cylinders are activated, and the X-axis cylinders drive the Z-axis height adjustment mechanism to slide along the X direction, further moving the Z-axis height adjustment pad to directly below the fixture support block. The Z-axis height adjustment pad is connected as one unit through the Z-axis height adjustment pad connecting shaft.

[0019] S4. Control the drive end of the Z-axis cylinder to retract downwards, causing the lifted clamp to fall until the clamp support block is stably supported on the Z-axis height adjustment pad.

[0020] The above solution achieves the following beneficial technical effects:

[0021] This application achieves precise positioning in the XYZ directions of the jig by lifting the jig in the Z direction, sliding the Z-direction height adjustment pad, and lowering it in the Z direction. This ensures the positioning accuracy of jig switching, which is beneficial to ensuring the repeatability of positioning accuracy in robot gripping and welding, thereby ensuring the stability of welding quality or the consistency of part gripping.

[0022] This application only requires manual pushing of the clamp to the working position with normal force, which perfectly solves the deformation effect caused by using a forklift to lift the clamp and the positioning pin hole, and avoids the method of multiple people using great force to push it into place, which greatly improves convenience and greatly reduces the labor intensity of the operator. Attached Figure Description

[0023] Figure 1 This is an overall structural diagram of a welding fixture switching flexible precision positioning mechanism provided in one or more embodiments of the present invention.

[0024] Figure 2 This is a front view structural diagram of a welding fixture switching flexible precision positioning mechanism provided in one or more embodiments of the present invention.

[0025] Figure 3 This is a partial structural diagram of the clamp wheel of a welding fixture switching flexible precision positioning mechanism provided in one or more embodiments of the present invention.

[0026] Figure 4 This is a top view of a flexible precision positioning mechanism for switching welding fixtures, provided in one or more embodiments of the present invention.

[0027] Figure 5 This is a partial structural diagram of the positioning pin of a flexible precision positioning mechanism for switching welding fixtures provided in one or more embodiments of the present invention.

[0028] Figure 6 This is a partial structural diagram of the Z-axis cylinder of a flexible precision positioning mechanism for switching welding fixtures provided in one or more embodiments of the present invention.

[0029] Figure 7 This is a partial structural diagram of the Z-axis height adjustment pad of a flexible precision positioning mechanism for switching welding fixtures provided in one or more embodiments of the present invention.

[0030] Figure 8 This is a partial structural diagram of the cylinder connector of a flexible precision positioning mechanism for switching welding fixtures provided in one or more embodiments of the present invention.

[0031] Figure 9 This is a partial structural diagram of the positioning block of a welding fixture switching flexible precision positioning mechanism provided in one or more embodiments of the present invention.

[0032] The components include: 1. Fixture; 2. Ground positioning mechanism; 3. Fixture wheel; 4. Fixture bottom base plate; 5. Fixture support block; 6. Fixture positioning pin sleeve; 7. Fixture guide plate; 8. Fixture positioning limit block; 9. Position sensor; 10. Fixture entry and exit guide wheel; 11. Positioning block; 12. Positioning pin; 13. Base plate; 14. Z-axis cylinder; 15. Cylinder connecting plate; 16. X-axis cylinder; 17. Z-axis height adjustment pad; 18. Z-axis height adjustment pad connecting shaft; 19. Cylinder connector. Detailed Implementation

[0033] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0034] Figures 1-9 This is a structural diagram of a welding fixture switching flexible precision positioning mechanism provided in one or more embodiments of the present invention.

[0035] like Figure 1 The welding fixture switching flexible precision positioning mechanism shown includes:

[0036] A clamp 1 is provided, and a ground positioning mechanism 2 is installed below the clamp 1. A clamp wheel 3 is fixedly installed below the clamp 1, and the height of the clamp wheel 3 is lower than that of the ground positioning mechanism 2. The ground positioning mechanism 2 includes a base plate 13, multiple Z-axis cylinders 14, multiple X-axis cylinders 16, and a Z-axis height adjustment mechanism. The X-axis cylinders 16 are used to drive the Z-axis height adjustment mechanism to slide along the X direction. A cylinder connecting plate 15 is fixedly connected to the outer wall of the Z-axis cylinder 14. The lower surface of the cylinder connecting plate 15 is installed on the upper surface of the base plate 13. A positioning execution mechanism is fixedly installed at the drive end of the Z-axis cylinder 14.

[0037] The welding fixture 1 with gripper wheels 3 is manually pushed to the fixture 1 switching position. When it reaches the designated position, the four sets of Z-axis telescopic cylinders 15 in the ground positioning mechanism 2 drive the two sets of positioning pins 12 and two sets of positioning blocks 11 to lift the fixture 1. After the fixture 1 is lifted, the horizontal X-axis cylinder 16 slides the Z-axis height adjustment pad 17 to the working position. Then, the Z-axis cylinder 14 drives the fixture to fall onto the Z-axis height adjustment pad 17, completing the precise positioning of the fixture 1. The precise positioning of the fixture 1 in the XYZ directions is achieved by lifting the fixture 1 in the Z direction, sliding the Z-axis height adjustment pad 17, and falling in the Z direction. This ensures the positioning accuracy of the fixture 1 switching, which is beneficial to the robot's gripping and welding repeatability accuracy, thereby ensuring the stability of welding quality or the consistency of part gripping.

[0038] Furthermore, the positioning actuator includes multiple sets of positioning blocks 11 and multiple sets of positioning pins 12. Cylinder connectors 19 are fixedly connected inside the positioning blocks 11 and positioning pins 12. The cylinder connectors 19 are installed on the drive end of the Z-axis cylinder 14. A clamp bottom BASE plate 4 is fixedly connected to the bottom of the clamp 1. Multiple clamp support blocks 5 are provided inside the clamp bottom BASE plate 4. The multiple clamp support blocks 5 correspond one-to-one with the multiple sets of positioning blocks 11.

[0039] By setting multiple sets of positioning blocks 11 and multiple sets of positioning pins 12, each set of positioning pins 12 and positioning blocks 11 is fixedly connected to the driving end of the corresponding Z-axis cylinder 14 through the cylinder connector 19, ensuring that the Z-axis cylinder 14 can drive the positioning pins 12 and positioning blocks 11 to move synchronously in the Z direction when it extends or retracts.

[0040] Furthermore, the bottom base plate 4 of the fixture is equipped with multiple fixture positioning pin sleeves 6, and the multiple fixture positioning pin sleeves 6 and multiple sets of positioning pins 12 correspond one-to-one.

[0041] By setting positioning pin sleeves 6 and positioning pins 12, and the two sets of positioning pins 12 are arranged symmetrically with one round pin and one diamond pin at the diagonal, they are respectively installed on the drive ends of the Z-direction cylinders 14 on the left and right sides of the ground positioning mechanism 2, and the diagonal spacing corresponds to the installation position of the two sets of clamp positioning pin sleeves 6 on the BASE plate 4 at the bottom of the clamp, thereby ensuring that the clamp 1 can move accurately in the X or Y direction.

[0042] Furthermore, the Z-axis height adjustment mechanism includes a Z-axis height adjustment pad 17 and a Z-axis height adjustment pad connecting shaft 18. The two ends of the Z-axis height adjustment pad connecting shaft 18 are fixedly connected to the inside of the Z-axis height adjustment pad 17. The inside of the Z-axis height adjustment pad 17 has multiple interconnected holes.

[0043] By setting up a Z-axis height adjustment pad 17 and a Z-axis height adjustment pad connecting shaft 18, the Z-axis height adjustment pad 17 is designed to be connected by a Z-axis height adjustment pad connecting shaft 18 to connect two Z-axis height adjustment pads 17 at the front and rear, and the Z-axis height adjustment pad 17 is designed to be connected by two circular holes of different diameters, so that the X-axis cylinder 16 can drive the Z-axis height adjustment pad 17 to slide back and forth through the positioning pin 12.

[0044] Furthermore, the ground positioning mechanism 2 is divided into left and right side structures, and the distance between the left and right side structures can be adaptively adjusted according to the size of the clamp 1.

[0045] The spacing between the ground positioning mechanisms 2 on the left and right sides can be adaptively adjusted according to the size of the clamp 1, thereby improving the high adaptability of the ground positioning mechanism 2.

[0046] Furthermore, a clamp guide plate 7 is provided at the bottom of the clamp 1, and a plurality of clamp entry and exit guide wheels 10 are slidably connected to the outer wall of the clamp guide plate 7. The clamp entry and exit guide wheels 10 are fixedly connected to the outer wall of the base plate 13.

[0047] By setting the clamp guide plate 7 and the clamp entry and exit guide wheel 10, the clamp entry and exit guide wheel 10 is used to limit the two sides of the clamp guide plate 7, which further ensures the smoothness of the clamp 1 when it moves, and can also effectively limit the lateral displacement of the clamp 1 when it moves.

[0048] Furthermore, a clamp positioning limit block 8 and a positioning sensor 9 are fixedly connected to the upper outer wall of the base plate 13, and the clamp positioning limit block 8 and the positioning sensor 9 are located on the same horizontal line.

[0049] When the clamp 1 is manually pushed to move under the guidance of the clamp entry and exit guide wheel 10, the side of the clamp 1 will gradually approach the clamp positioning limit block 8 until it is in contact with the limiting surface of the clamp positioning limit block 8, thereby achieving mechanical positioning of the clamp 1. At this time, the positioning sensor 9 senses that the clamp 1 has reached the preset position and then sends a positioning signal to trigger the Z-axis cylinder 14 to perform lifting operation. The sensing signal of the positioning sensor 9 provides a precise triggering time for each cylinder, thereby avoiding mutual interference between the structures.

[0050] Furthermore, the cylinder connecting plate 15 is detachably connected to the base plate 13 by bolts, and the cylinder connecting piece 19 has a groove inside, the shape and size of which are adapted to the drive end of the Z-axis cylinder 14.

[0051] The modular design facilitates the individual disassembly of each component for easy maintenance and replacement. The interlocking between the groove inside the cylinder connector 19 and the drive end of the Z-axis cylinder 14 ensures the stability of the connection and also facilitates the disassembly of the cylinder connector 19 by the operator.

[0052] A method for operating a welding fixture switching flexible precision positioning mechanism, used in any one of claims 1-9, comprising:

[0053] S1. Push the fixture 1 along the preset path, so that the fixture guide plate 7 at the bottom of the fixture 1 slides under the guidance of the fixture entry and exit guide wheel 10 fixed on the base BASE plate 13 until the fixture 1 contacts the fixture position limit block 8 and is mechanically limited. At the same time, the position sensor 9 detects that the fixture 1 has reached the preset position and sends a position signal to the external control system.

[0054] S2. After receiving the positioning signal, multiple Z-axis cylinders 14 are activated, causing their drive ends to move upward. Through the cylinder connector 19, multiple sets of positioning blocks 11 and multiple sets of positioning pins 12 in the positioning actuator rise synchronously, further causing the positioning blocks 11 to contact and lift the clamp support blocks 5 in the bottom BASE plate 4 of the clamp. At this time, the positioning pins 12 are inserted into the corresponding clamp positioning pin sleeves 6 in the bottom BASE plate 4 of the clamp, thereby lifting the entire clamp 1 and causing the clamp wheels 3 below it to leave the ground.

[0055] S3. After the fixture 1 is lifted, multiple X-axis cylinders 16 are activated. The X-axis cylinders 16 drive the Z-axis height adjustment mechanism to slide along the X direction, further moving the Z-axis height adjustment pad 17 directly below the fixture support block 5. The Z-axis height adjustment pad 17 is connected as one unit through the Z-axis height adjustment pad connecting shaft 18.

[0056] S4. Control the drive end of the Z-axis cylinder 14 to retract downwards, causing the lifted clamp 1 to fall until the clamp support block 5 is stably supported on the Z-axis height adjustment pad 17.

[0057] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A flexible precision positioning mechanism for switching welding fixtures, characterized in that, The device includes a clamp (1), a ground positioning mechanism (2) is installed below the clamp (1), a clamp wheel (3) is fixedly installed below the clamp (1), and the height of the clamp wheel (3) is lower than that of the ground positioning mechanism (2). The ground positioning mechanism (2) includes a base plate (13), multiple Z-axis cylinders (14), multiple X-axis cylinders (16) and a Z-axis height adjustment mechanism. The X-axis cylinder (16) is used to drive the Z-axis height adjustment mechanism to slide along the X direction. The outer wall of the Z-axis cylinder (14) is fixedly connected to a cylinder connecting plate (15). The lower surface of the cylinder connecting plate (15) is installed on the upper surface of the base plate (13). The driving end of the Z-axis cylinder (14) is fixedly installed with a positioning execution mechanism.

2. The flexible precision positioning mechanism for switching welding fixtures according to claim 1, characterized in that, The positioning actuator includes multiple sets of positioning blocks (11) and multiple sets of positioning pins (12). The positioning blocks (11) and positioning pins (12) are internally fixedly connected to cylinder connectors (19), which are installed at the drive end of the Z-axis cylinder (14).

3. The flexible precision positioning mechanism for switching welding fixtures according to claim 2, characterized in that, The bottom of the clamp (1) is fixedly connected to a clamp bottom BASE plate (4), and multiple clamp support blocks (5) are provided inside the clamp bottom BASE plate (4). The multiple clamp support blocks (5) correspond one-to-one with multiple sets of positioning blocks (11).

4. The flexible precision positioning mechanism for switching welding fixtures according to claim 2, characterized in that, The bottom BASE plate (4) of the fixture is provided with multiple fixture positioning pin sleeves (6), and the multiple fixture positioning pin sleeves (6) correspond one-to-one with multiple sets of positioning pins (12).

5. The flexible precision positioning mechanism for switching welding fixtures according to claim 1, characterized in that, The Z-axis height adjustment mechanism includes a Z-axis height adjustment pad (17) and a Z-axis height adjustment pad connecting shaft (18). The two ends of the Z-axis height adjustment pad connecting shaft (18) are fixedly connected to the inside of the Z-axis height adjustment pad (17). The inside of the Z-axis height adjustment pad (17) has multiple interconnected holes.

6. The flexible precision positioning mechanism for switching welding fixtures according to claim 1, characterized in that, The ground positioning mechanism (2) is divided into left and right side structures, and the distance between the left and right side structures can be adaptively adjusted according to the size of the clamp (1).

7. The flexible precision positioning mechanism for switching welding fixtures according to claim 1, characterized in that, The bottom of the clamp (1) is provided with a clamp guide plate (7), and the outer wall of the clamp guide plate (7) is slidably connected with a plurality of clamp entry and exit guide wheels (10), and the clamp entry and exit guide wheels (10) are fixedly connected to the outer wall of the base plate (13).

8. The flexible precision positioning mechanism for switching welding fixtures according to claim 1, characterized in that, The upper outer wall of the base plate (13) is fixedly connected to a clamp positioning limit block (8) and a positioning sensor (9), and the clamp positioning limit block (8) and the positioning sensor (9) are located on the same horizontal line.

9. The flexible precision positioning mechanism for switching welding fixtures according to claim 2, characterized in that, The cylinder connecting plate (15) is detachably connected to the base plate (13) by bolts. The cylinder connecting piece (19) has a groove inside, and the shape and size of the groove are adapted to the drive end of the Z-axis cylinder (14).

10. A method for operating a flexible precision positioning mechanism for switching welding fixtures, characterized in that, A flexible precision positioning mechanism for switching welding fixtures as described in any one of claims 1-9 includes: S1. Push the fixture (1) along the preset path, so that the fixture guide plate (7) at the bottom of the fixture (1) slides under the guidance of the fixture entry and exit guide wheel (10) fixed on the base BASE plate (13) until the fixture (1) contacts the fixture positioning limit block (8) and is mechanically limited. At the same time, the positioning sensor (9) detects that the fixture (1) has reached the preset position and sends a positioning signal to the external control system. S2. After receiving the positioning signal, multiple Z-axis cylinders (14) are activated, causing their drive ends to move upward. Through the cylinder connector (19), multiple positioning blocks (11) and multiple positioning pins (12) in the positioning actuator rise synchronously, further causing the positioning blocks (11) to contact and lift the fixture support blocks (5) in the bottom BASE plate (4) of the fixture. At this time, the positioning pins (12) are inserted into the corresponding fixture positioning pin sleeves (6) in the bottom BASE plate (4) of the fixture, thereby lifting the entire fixture (1) and causing the fixture wheels (3) below it to leave the ground. S3. After the fixture (1) is lifted, multiple X-direction cylinders (16) are activated. The X-direction cylinders (16) drive the Z-direction height adjustment mechanism to slide along the X direction, further moving the Z-direction height adjustment pad (17) directly below the fixture support block (5). The Z-direction height adjustment pad (17) is connected as one unit through the Z-direction height adjustment pad connecting shaft (18). S4. Control the drive end of the Z-axis cylinder (14) to retract downward, causing the lifted clamp (1) to fall until the clamp support block (5) is stably supported on the Z-axis height adjustment pad (17).

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