Automatic feeding and discharging mechanism and multi-station projection welding machine

By setting two feeding mechanical claws and a correction mechanical claw in the projection welding equipment, synchronous loading and unloading are achieved using the same moving drive mechanism, and the workpiece posture is corrected by a vision inspection mechanism. This solves the problems of low production efficiency and high cost in the existing technology and realizes efficient and precise welding operation.

CN121945948APending Publication Date: 2026-05-01DALIAN YUANYANG TECH CO LTD
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Patent Information

Authority / Receiving Office
CN · China
Patent Type
Applications(China)
Current Assignee / Owner
DALIAN YUANYANG TECH CO LTD
Filing Date
2026-03-20
Publication Date
2026-05-01

AI Technical Summary

Technical Problem

In existing projection welding equipment, the robot gripper needs to perform loading and unloading operations sequentially, resulting in low production efficiency, and adding more robots will increase equipment costs.

Method used

It employs two feeding mechanical grippers and one correction mechanical gripper, all linked by the same moving drive mechanism, to achieve synchronous execution of loading and unloading, and uses a vision inspection mechanism to correct the workpiece posture.

Benefits of technology

It effectively shortens the waiting time at the projection welding station, improves production efficiency, ensures accurate workpiece welding positioning, and reduces equipment costs and maintenance difficulty.

✦ Generated by Eureka AI based on patent content.

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Abstract

The invention belongs to the technical field of projection welding equipment, and discloses an automatic feeding and discharging mechanism and a multi-station projection welding machine which comprises the automatic feeding and discharging mechanism and a projection welding mechanism arranged on one side of the automatic feeding and discharging mechanism. A projection welding station matched with the projection welding station automatic feeding and discharging mechanism is formed between an upper electrode and a lower electrode of the projection welding mechanism. The automatic feeding and discharging mechanism comprises two feeding mechanical claws and a moving driving mechanism. Wherein one feeding mechanical claw is configured to release an unwelded workpiece in the projection welding station between the upper electrode and the lower electrode, and the other feeding mechanical claw is configured to pick up a welded workpiece in the projection welding station between the upper electrode and the lower electrode; and the movement driving mechanism is connected with the two feeding mechanical claws and is configured to drive the two feeding mechanical claws to move in the parallel direction and / or the vertical direction in a linkage mode so that the two feeding mechanical claws can alternately move into the projection welding station.
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Description

An automatic loading and unloading mechanism and a multi-station projection welding machine Technical Field

[0001] This invention belongs to the technical field of projection welding equipment, specifically relating to an automatic loading and unloading mechanism and a multi-station projection welding machine. Background Technology

[0002] Projection welding is a highly efficient welding process widely used in automobile manufacturing, home appliances and other fields. It is often used to weld fasteners such as nuts to the surface of workpieces.

[0003] In existing projection welding equipment, such as the projection welding workstation disclosed in patent CN223603637U, the workpiece is grasped and transported using a robot and grippers. However, in actual operation, the robot's grippers need to perform loading and unloading operations sequentially. That is, the grippers must first place the workpiece to be welded into the projection welding station, then exit and wait for the welding to complete, and then re-enter the projection welding station to pick up the welded workpiece. During this process, both the robot and the projection welding station need to wait for a certain amount of time, resulting in low equipment production efficiency. In addition, increasing the number of robots to improve production efficiency would significantly increase the equipment's usage and maintenance costs. Summary of the Invention

[0004] In view of this, in order to solve the problems mentioned in the background art, the purpose of the present invention is to provide an automatic loading and unloading mechanism and a multi-station projection welding machine.

[0005] To achieve the above objectives, the present invention provides the following technical solution: an automatic loading and unloading mechanism for a multi-station projection welding machine, comprising: two feeding mechanical claws, one of which is configured to release an unwelded workpiece within a projection welding station between an upper electrode and a lower electrode, and the other of which is configured to pick up a welded workpiece within the projection welding station between the upper electrode and the lower electrode; a movement drive mechanism connected to the two feeding mechanical claws, configured to drive the two feeding mechanical claws to move in a parallel direction and / or in a vertical direction, so that the two feeding mechanical claws alternately move into the projection welding station; wherein the upper electrode and the lower electrode weld a workpiece and a nut at the projection welding station.

[0006] In the above technical solution, by setting up two clearly defined feeding mechanical claws and driving them together by the same moving drive mechanism, the synchronous execution of loading and unloading is realized, thereby effectively shortening the waiting time of the projection welding station and improving production efficiency.

[0007] Preferably, the automatic loading and unloading mechanism further includes a correction mechanical claw mounted on the mobile drive mechanism, the correction mechanical claw being configured to correct the posture of the unwelded workpiece on the upstream side of the feeding mechanical claw.

[0008] Preferably, a bracket is mounted on the mobile drive mechanism, and a rotary cylinder for driving the correction mechanical gripper to rotate around the Z-axis is mounted on the bracket.

[0009] In the above technical solution, by introducing a correction mechanical gripper into the feeding path and synchronously driving it with the same moving drive mechanism, the problem of workpiece posture deviation is pre-processed before loading, thereby ensuring that the feeding mechanical gripper can accurately transport the workpiece to the projection welding station. Furthermore, synchronous driving achieves effective coordination of correction, loading, and unloading.

[0010] Preferably, the moving drive mechanism includes an X-axis moving mechanism, a Y-axis moving mechanism, and a Z-axis moving mechanism. The two feeding mechanical claws and the correcting mechanical claw are arranged side by side in the X-axis direction, and the central axis of the correcting mechanical claw extends along the Z-axis direction, while the central axes of the two feeding mechanical claws extend along the Y-axis direction.

[0011] Preferably, the automatic loading and unloading mechanism further includes an X-axis feeding channel and a Y-axis feeding channel connected end to end. A calibration station and a loading station are set in the X-axis feeding channel. The calibration mechanical claw is configured to calibrate the unwelded workpiece at the calibration station and then transport it to the loading station. One of the feeding mechanical claws is configured to pick up the unwelded workpiece at the loading station.

[0012] Preferably, the calibration station is provided with first blocks symmetrically distributed on both sides of the X-axis feeding channel, and a material picking channel that cooperates with the calibration mechanical claw is formed between the two sets of first blocks; the loading station is provided with second blocks that form a loading positioning groove, and the loading positioning groove has slots on both sides that cooperate with the feeding mechanical claw.

[0013] In the above technical solution, the setting of the first stop ensures that the workpiece can be accurately positioned to the calibration station, and is also compatible with the operation of the calibration mechanical claw picking up the workpiece from above the X-axis feeding channel; the setting of the second stop ensures that the workpiece can be accurately positioned to the loading station, and is also compatible with the operation of the feeding mechanical claw picking up the workpiece from the horizontal side of the X-axis feeding channel.

[0014] Preferably, the automatic loading and unloading mechanism further includes a pushing mechanism, which is arranged along the X-axis at the beginning of the X-axis feeding channel, for pushing the unwelded workpiece at the junction of the X-axis feeding channel and the Y-axis feeding channel to the calibration station; the pushing mechanism includes a pushing cylinder and a pushing rod.

[0015] Preferably, a vision inspection mechanism is provided at the connection between the X-axis feeding channel and the Y-axis feeding channel. The rotary cylinder drives the correction mechanical claw to rotate around the Z-axis to correct the unwelded workpiece in response to the detection result of the vision inspection mechanism. The vision inspection mechanism includes a cover plate fixed at the connection between the X-axis feeding channel and the Y-axis feeding channel and a vision camera mounted on the cover plate by a support frame. The cover plate has a detection through hole that cooperates with the vision camera.

[0016] In the above technical solution, the cover plate provides basic support for the installation of the vision camera and ensures that the workpiece can be smoothly transported at the connection between the X-axis feeding channel and the Y-axis feeding channel, thus preventing the workpiece from falling out of the feeding channel.

[0017] Preferably, the automatic loading and unloading mechanism further includes a vibrating loading plate connected to the first end of the Y-axis feeding channel and a unloading guide groove that cooperates with the feeding mechanical claw.

[0018] Furthermore, the present invention also provides a multi-station projection welding machine, including any of the automatic loading and unloading mechanisms described in any one of the claims and a projection welding mechanism disposed on one side of the automatic loading and unloading mechanism. The upper electrode and the lower electrode of the projection welding mechanism form a projection welding station adapted to the automatic loading and unloading mechanism of the projection welding station. The upper end of the unloading guide groove is connected to a support plate extending into the projection welding station. A welding through groove is formed on the support plate to cooperate with the upper electrode and the lower electrode. When the workpiece is welded in the projection welding station, it is supported on the top of the support plate.

[0019] In the above technical solution, the support plate provides stable support for the workpiece at the projection welding station, ensuring the stability of workpiece welding and conveying positioning. At the same time, the welding through groove ensures that the upper and lower electrodes can effectively contact each other, ensuring the effective execution of projection welding.

[0020] Compared with the prior art, the present invention has the following beneficial effects: The present invention provides an automatic loading and unloading mechanism and a multi-station projection welding machine, which specifically sets up a calibration station, a loading station and a projection welding station, etc., and drives the calibration mechanical claw and two feeding mechanical claws to perform loading and unloading operations synchronously at each station through a moving drive mechanism, realizing effective coordination of calibration, loading and unloading, thereby greatly shortening the waiting time of the projection welding station, improving processing efficiency, and the overall structure is simple, low in cost and convenient for inspection and maintenance.

[0021] In addition, the correction of the mechanical gripper, in conjunction with the vision inspection mechanism, enables active correction of the workpiece posture, further ensuring the accuracy of workpiece welding positioning, thereby significantly improving welding quality. Attached Figure Description

[0022] Figure 1 is a structural schematic diagram of the multi-station projection welding machine of the present invention; Figure 2 is a structural schematic diagram of the automatic loading and unloading mechanism of the present invention; Figure 3 is a structural schematic diagram of the assembly of the feeding mechanical claw, the moving drive mechanism and the correcting mechanical claw in the automatic loading and unloading mechanism; Figure 4 is a structural schematic diagram of the assembly of the X-axis feeding channel, the Y-axis feeding channel and the pushing mechanism in the automatic loading and unloading mechanism; Figure 5 is a structural schematic diagram of the assembly of the X-axis feeding channel and the pushing mechanism in the automatic loading and unloading mechanism; Figure 6 is an enlarged view of point A in Figure 1; Figure 7 is an enlarged view of point B in Figure 4; In the figures: Automatic loading and unloading mechanism -100; Projection welding mechanism -200; Feeding mechanical claw -1; Moving drive mechanism -2; X-axis moving mechanism -21; Y-axis moving mechanism -22; Z-axis moving mechanism -23; Correction mechanical claw -3; Mounting bracket -31; Rotary cylinder -32; X-axis feeding channel -4; First stop -41; Second stop -42; Y-axis feeding channel -5; Pushing mechanism -6; Pushing cylinder -61; Pushing rod -62; Vision inspection mechanism -7; Cover plate -71; Support frame -72; Vision camera -73; Inspection through hole -74; Vibrating feeder -8; Unloading guide groove -9; Support plate -91. Detailed Implementation

[0023] To further understand the content of this invention, a detailed description of the invention is provided in conjunction with the accompanying drawings and embodiments. The structures, proportions, sizes, etc., depicted in the accompanying drawings are merely for illustrative purposes and to aid those skilled in the art, and are not intended to limit the implementation conditions of the invention. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to size, without affecting the effects and objectives of the invention, should still fall within the scope of the technical content disclosed in this invention. Furthermore, terms such as "upper," "lower," "left," "right," and "middle" used in this specification are merely for clarity and not intended to limit the scope of implementation. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of the invention. It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate for the embodiments of this application described herein.

[0024] As shown in Figure 1, the present invention provides a multi-station projection welding machine equipped with an automatic loading and unloading mechanism 100 and a projection welding mechanism 200, wherein the automatic loading and unloading mechanism 100 is disposed on one side of the projection welding mechanism 200. The projection welding mechanism 200 includes a frame and an upper electrode and a lower electrode disposed on the frame, and a projection welding station adapted to the automatic loading and unloading mechanism 100 is formed between the upper electrode and the lower electrode.

[0025] Referring again to Figures 2-7, the automatic loading and unloading mechanism 100 includes two feeding mechanical claws 1, a moving drive mechanism 2, a correcting mechanical claw 3, an X-axis feeding channel 4, a Y-axis feeding channel 5, a pushing mechanism 6, a vision inspection mechanism 7, a vibrating loading tray 8, and a unloading guide chute 9. The two feeding mechanical claws 1 and the correcting mechanical claw 3 are arranged side-by-side in the X-axis direction, with the central axis of the correcting mechanical claw 3 extending along the Z-axis direction, and the central axes of the two feeding mechanical claws 1 extending along the Y-axis direction. In this structural design, the correcting mechanical claw 3 performs the workpiece picking operation above the X-axis feeding channel 4; the feeding mechanical claws 1 perform the workpiece picking operation on the horizontal side of the X-axis feeding channel 4. Furthermore, one of the feeding mechanical claws 1 is configured to pick up unwelded workpieces at the loading station and release unwelded workpieces in the projection welding station between the upper and lower electrodes; the other feeding mechanical claw 1 is configured to pick up welded workpieces in the projection welding station between the upper and lower electrodes; the correction mechanical claw 3 is configured to correct the unwelded workpieces at the correction station and then transport them to the loading station.

[0026] The following is a detailed description of each structure according to the workpiece feeding sequence: Continuing to refer to Figure 2, the vibrating feeding plate 8 is connected to the first end of the Y-axis feeding channel 5, so as to facilitate the orderly transportation of unwelded workpieces to the Y-axis feeding channel 5.

[0027] Referring again to Figures 2 and 4, the first end of the X-axis feeding channel 4 is perpendicularly connected to the end of the Y-axis feeding channel 5, and the pushing mechanism 6 is arranged at the first end of the X-axis feeding channel 4, extending along the X-axis. Therefore, when a workpiece is conveyed from the Y-axis feeding channel 5 to the X-axis feeding channel 4, the pushing mechanism 6 enables intermittent conveying of the workpiece within the X-axis feeding channel 4. Specifically, the pushing mechanism 6 includes a pushing cylinder 61 and a pushing rod 62. Taking the rectangular cross-section workpiece shown in Figure 4 as an example, the Y-axis feeding channel 5 is adapted to the workpiece width, and the X-axis feeding channel 4 is adapted to the workpiece length. When a workpiece at the very front of the Y-axis feeding channel 5 is conveyed to the connection point between the X-axis feeding channel 4 and the Y-axis feeding channel 5, the pushing cylinder 61 is activated, so that the pushing rod 62 pushes the workpiece to move along the X-axis direction within the X-axis feeding channel 4.

[0028] It should be noted that, as shown in Figures 4 and 5, a calibration station and a loading station are provided in the X-axis feeding channel 4, and the pushing mechanism 6 is used to push the unwelded workpiece at the connection between the X-axis feeding channel 4 and the Y-axis feeding channel 5 to the calibration station.

[0029] Furthermore, to improve the positioning accuracy of the workpiece at the calibration station and the loading station, as shown in Figure 5, the calibration station is provided with first blocks 41 symmetrically distributed on both sides of the X-axis feeding channel 4, and a material picking channel that cooperates with the calibration mechanical claw 3 is formed between the two sets of first blocks 41; the loading station is provided with second blocks 42 forming a loading positioning groove, and the loading positioning groove has slots on both sides that cooperate with the feeding mechanical claw 1, thereby facilitating the material picking operation of the calibration mechanical claw 3 and the feeding mechanical claw 1.

[0030] Referring again to Figures 4 and 7, the vision inspection mechanism 7 is located at the connection between the X-axis feed channel 4 and the Y-axis feed channel 5. Specifically, the vision inspection mechanism 7 includes a cover plate 71 fixed at the connection between the X-axis feed channel 4 and the Y-axis feed channel 5, and a vision camera 73 mounted on the cover plate 71 via a support frame 72. The cover plate 71 has a detection through hole 74 that cooperates with the vision camera 73. The cover plate 71 provides a basic support for the installation of the vision camera 73 and ensures that the workpiece can be smoothly conveyed at the connection between the X-axis feed channel 4 and the Y-axis feed channel 5, preventing the workpiece from falling out of the feed channel.

[0031] Referring again to Figure 3, both the feeding mechanical gripper 1 and the correcting mechanical gripper 3 include an actuating cylinder and two grippers that can clamp or release towards each other under the drive of the actuating cylinder. The grippers of the feeding mechanical gripper 1 include a clamping arm and a connecting arm that connects the clamping arm to the actuating cylinder drive arm. The connecting arm includes a straight arm and a slanted arm, so that the height of the clamping arm in the Z-axis direction is lower than that of the drive arm. This ensures effective clamping of the workpiece by the clamping arm and avoids structural interference between the horizontal installation of the feeding mechanical gripper 1 and the moving drive mechanism 2. The correcting mechanical gripper 3 is cantilevered via a bracket 31 to ensure that the correcting mechanical gripper 3 can perform effective posture correction on the workpiece.

[0032] Referring again to Figure 3, the moving drive mechanism 2 includes an X-axis moving mechanism 21, a Y-axis moving mechanism 22, and a Z-axis moving mechanism 23, thereby effectively realizing three-axis linkage during the operation of the feeding mechanical claw 1 and the correcting mechanical claw 3. Specifically, the Z-axis moving mechanism 23 serves as the overall support base, the X-axis moving mechanism 21 is mounted on the lifting slider of the Z-axis moving mechanism 23, and the Y-axis moving mechanism 22 is mounted on the moving slider of the X-axis moving mechanism 21. Simultaneously, a mounting plate extending along the X-axis direction is fixed to the moving slider of the Y-axis moving mechanism 22. The actuator cylinders of the two feeding mechanical claws 1 and the bracket 31 of the correcting mechanical claw 3 are all mounted on the mounting plate, thus achieving integrated installation of the overall structure, resulting in a simple and compact structure.

[0033] It should be noted that a rotary cylinder 32 for driving the correction mechanical gripper 3 to rotate around the Z-axis is installed on the bracket 31. Thus, when the correction mechanical gripper 3 is used to correct the workpiece posture, the workpiece can be rotated 180° around the Z-axis to ensure that the preset welding points on the workpiece are precisely aligned with the upper and lower electrodes.

[0034] Referring again to Figures 1 and 2, the unloading guide groove 9 is located at the end of the X-axis feed channel 4 to receive the welded workpiece unloaded by the feeding mechanical claw 1. Furthermore, as shown in Figure 7, the upper end of the unloading guide groove 9 is connected to a support plate 91 extending into the projection welding station. The support plate 91 has welding slots that mate with the upper and lower electrodes, ensuring that when the workpiece is welded in the projection welding station, it is supported on top of the support plate 91. The upper and lower electrodes are aligned and contacted with the workpiece through the welding slots, thereby welding the nut to the workpiece. The nut can be fed by an automatic nut feeding mechanism (not shown in the figure), which is a known and publicly disclosed technology and will not be described in detail here.

[0035] In summary, the specific working process of the projection welding machine provided by this invention includes: feeding: the vibrating feeding plate 8 orderly conveys the unwelded workpiece to the Y-axis feeding channel 5, and the workpiece moves along the Y-axis feeding channel 5 to the connection point with the X-axis feeding channel 4; visual inspection: after the workpiece reaches the connection point between the Y-axis feeding channel 5 and the X-axis feeding channel 4, the visual camera 73 takes pictures of the workpiece through the detection through hole 74 on the cover plate 71 to identify the current posture of the workpiece (mainly the rotation angle in the horizontal plane); pushing: the pushing cylinder 61 The drive pusher 62 pushes the workpiece along the X-axis to the calibration station. Calibration, loading, and unloading: After the workpiece reaches the calibration station, it is blocked by two sets of first stops 41. The Z-axis moving mechanism 23 drives the two feeding mechanical claws 1 and the calibration mechanical claw 3 to descend synchronously, so that the grippers of the two feeding mechanical claws 1 are positioned at the loading station and the projection welding station respectively, while the grippers of the calibration mechanical claw 3 are positioned at the calibration station. The two feeding mechanical claws 1 and the calibration mechanical claw 3 synchronously pick up the workpiece at the corresponding station, and then the Z-axis moving mechanism 23 rises and resets. The X-axis moving mechanism 21 drives the two feeding mechanical claws 1 and the calibration mechanical claw 3 to move synchronously along the X-axis. One feeding mechanical claw 1, which picks up the welded workpiece at the projection welding station, moves above the unloading guide 9; the other feeding mechanical claw 1, which picks up the unwelded workpiece at the loading station, moves above the projection welding station; and the calibration mechanical claw 3 moves above the loading station. The Z-axis moving mechanism 23 drives the downward movement, and the two feeding mechanical claws 1 and the correction mechanical claw 3 synchronously release the workpiece, thereby synchronously correcting, loading, and unloading the complete workpiece. Specifically, the workpiece correction operation is as follows: during the movement of the correction mechanical claw 3 from the correction station to the loading station, based on the detection results of the vision camera 73, the rotary cylinder 32 drives the correction mechanical claw 3 to rotate around the Z-axis by a corresponding correction angle (calculated by a program written in the controller). For the rectangular cross-section product shown in the figure, the correction angle is 180°. Welding: the workpiece and nut at the projection welding station are welded using the upper and lower electrodes of the projection welding mechanism 200. Simultaneously, the Y-axis moving mechanism 22 drives the two feeding mechanical claws 1 and the correction mechanical claw 3, after releasing the workpiece, to move along the Y-axis, so that the grippers of the feeding mechanical claws 1 move away from the upper and lower electrodes of the projection welding mechanism 200. Then, the Z-axis moving mechanism 23 rises and resets, and the X-axis moving mechanism 21 moves back and resets, so as to perform the synchronous operation of correction, loading, and unloading again.

[0036] By repeating the above steps, continuous automated production can be achieved.

[0037] This invention sets up two feeding mechanical claws 1 and one correction mechanical claw 3, which are driven by the same moving drive mechanism 2 to realize the synchronous execution of workpiece correction, loading and unloading. This effectively solves the problems of low loading and unloading efficiency, inaccurate workpiece positioning and high equipment cost in the prior art. As a result, the projection welding machine of this invention has the advantages of high production efficiency, good positioning accuracy, simple and compact structure and stable operation.

[0038] In the description of this invention, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0039] Note that the above description is merely a preferred embodiment of the present invention and the technical principles employed. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and various obvious changes, readjustments, and substitutions can be made without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments, and may include many other equivalent embodiments without departing from the concept of the present invention, the scope of which is determined by the scope of the appended claims.

Claims

1. An automatic loading and unloading mechanism for a multi-station projection welding machine, characterized in that, include: Two feeding mechanical claws (1), one of which is configured to release an unwelded workpiece in a projection welding station between the upper and lower electrodes, and the other of which is configured to pick up a welded workpiece in a projection welding station between the upper and lower electrodes; a moving drive mechanism (2) is connected to the two feeding mechanical claws (1) and configured to drive the two feeding mechanical claws (1) to move in a parallel direction and / or in a vertical direction, so that the two feeding mechanical claws (1) alternately move into the projection welding station; wherein the upper and lower electrodes weld the workpiece and the nut in the projection welding station.

2. The automatic loading and unloading mechanism for a multi-station projection welding machine according to claim 1, characterized in that: It also includes a correction mechanical gripper (3) mounted on the mobile drive mechanism (2), the correction mechanical gripper (3) being configured to correct the posture of the unwelded workpiece on the upstream side of the feeding mechanical gripper (1).

3. The automatic loading and unloading mechanism for a multi-station projection welding machine according to claim 2, characterized in that: A bracket (31) is mounted on the mobile drive mechanism (2), and a rotary cylinder (32) for driving the correction mechanical claw (3) to rotate around the Z-axis is mounted on the bracket (31).

4. The automatic loading and unloading mechanism for a multi-station projection welding machine according to claim 3, characterized in that: The moving drive mechanism (2) includes an X-axis moving mechanism (21), a Y-axis moving mechanism (22) and a Z-axis moving mechanism (23). The two feeding mechanical claws (1) and the correction mechanical claw (3) are arranged side by side in the X-axis direction, and the central axis of the correction mechanical claw (3) extends along the Z-axis direction, while the central axis of the two feeding mechanical claws (1) extends along the Y-axis direction.

5. The automatic loading and unloading mechanism for a multi-station projection welding machine according to claim 4, characterized in that: It also includes an X-axis feeding channel (4) and a Y-axis feeding channel (5) connected end to end. The X-axis feeding channel (4) is equipped with a calibration station and a loading station. The calibration mechanical claw (3) is configured to calibrate the unwelded workpiece at the calibration station and then transport it to the loading station. One of the feeding mechanical claws (1) is configured to pick up the unwelded workpiece at the loading station.

6. The automatic loading and unloading mechanism for a multi-station projection welding machine according to claim 5, characterized in that: The calibration station is provided with first blocks (41) symmetrically distributed on both sides of the X-axis feeding channel (4), and a material picking channel is formed between the two sets of first blocks (41) to cooperate with the calibration mechanical claw (3); the loading station is provided with second blocks (42) forming a loading positioning groove, and the loading positioning groove has slots on both sides to cooperate with the feeding mechanical claw (1).

7. The automatic loading and unloading mechanism for a multi-station projection welding machine according to claim 5, characterized in that: It also includes a pusher mechanism (6), which is set at the beginning of the X-axis feed channel (4) along the X-axis and is used to push the unwelded workpiece at the connection between the X-axis feed channel (4) and the Y-axis feed channel (5) to the correction station; the pusher mechanism (6) includes a pusher cylinder (61) and a pusher rod (62).

8. The automatic loading and unloading mechanism for a multi-station projection welding machine according to claim 5, characterized in that: A vision inspection mechanism (7) is provided at the connection between the X-axis feed channel (4) and the Y-axis feed channel (5). The rotary cylinder (32) drives the correction mechanical claw (3) to rotate around the Z-axis to correct the unwelded workpiece in response to the detection result of the vision inspection mechanism (7). The vision inspection mechanism (7) includes a cover plate (71) fixed at the connection between the X-axis feed channel (4) and the Y-axis feed channel (5) and a vision camera (73) mounted on the cover plate (71) by a support frame (72). The cover plate (71) is provided with a detection through hole (74) that cooperates with the vision camera (73).

9. The automatic loading and unloading mechanism for a multi-station projection welding machine according to claim 5, characterized in that: It also includes a vibrating feeder (8) connected to the beginning of the Y-axis feed channel (5) and a discharge guide (9) that cooperates with the feeding mechanical claw (1).

10. A multi-station projection welding machine, characterized in that: The automatic loading and unloading mechanism (100) as described in any one of claims 1-9 and the projection welding mechanism (200) disposed on one side of the automatic loading and unloading mechanism (100) are included. The upper electrode and the lower electrode of the projection welding mechanism (200) form a projection welding station adapted to the automatic loading and unloading mechanism (100) of the projection welding station. The upper end of the unloading guide groove (9) is connected to a support plate (91) extending into the projection welding station. A welding through groove is opened on the support plate (91) to cooperate with the upper electrode and the lower electrode. When the workpiece is welded in the projection welding station, it is supported on the top of the support plate (91).