Resistance spot welding C-type direct-drive electric cylinder
The C-type direct-drive electric cylinder for resistance spot welding, driven by a servo motor and ball screw, solves the problem of low electrode movement accuracy, achieves high-precision electrode movement, improves welding quality, and reduces maintenance costs.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-31
- Publication Date
- 2026-03-03
AI Technical Summary
The existing resistance spot welding machine uses an electric cylinder as the driving mechanism to move the electrode. The large impact force results in low clamping accuracy between the electrode and the thin plate, which can easily damage the thin plate and affect the processing quality.
A servo motor directly drives the ball screw to rotate, which converts the radial rotation into the linear motion of the push rod. The linear motion accuracy of the push rod is ensured by the ball nut and guide limit structure. The servo motor and cylinder are combined into one unit to improve the transmission accuracy.
It improves the accuracy of electrode movement position, ensures welding quality, saves installation space, reduces usage and maintenance costs, and facilitates widespread application.
Smart Images
Figure CN223960686U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of resistance spot welding, and in particular to a C-type direct-drive electric cylinder for resistance spot welding. Background Technology
[0002] Resistance spot welding is a type of resistance welding, mainly suitable for welding thin plate parts, such as automotive panels, aerospace, and shipbuilding. The process involves clamping the assembled plate parts with two symmetrical electrodes. After the plates are assembled, pressure is applied through the two symmetrical electrodes. The resistance heating effect generated by the current flowing through the contact surface and adjacent areas of the workpiece heats the corresponding parts of the electrodes to a melting or plastic state, so that the parts of the assembled plates form a metal bond at the corresponding electrode locations, thus achieving welding.
[0003] In a resistance spot welding machine, one of the two corresponding electrodes is usually fixed, while the other electrode is driven by a linear drive mechanism to move relative to the fixed electrode. The thin plate to be welded is placed between the two corresponding electrodes, and the drive mechanism drives the electrode connected to it to move towards the fixed electrode, clamping the thin plate for spot welding.
[0004] In existing resistance spot welding machines, the driving mechanism for driving the electrode movement uses an electric cylinder. However, the existing electric cylinder has a relatively large impact force, and the clamping accuracy between the electrode and the thin plate is not high. This can easily cause the connected electrode to crush the thin plate, i.e., the workpiece, resulting in product defects and affecting the processing quality of the thin plate. Summary of the Invention
[0005] The technical problem to be solved by this utility model is to provide a resistance spot welding C-type direct drive electric cylinder with high transmission accuracy and the ability to ensure the accuracy of electrode movement position.
[0006] To solve the above-mentioned technical problems, this utility model is achieved through the following technical solution:
[0007] A C-type direct-drive electric cylinder for resistance spot welding includes a cylinder barrel. A transmission cavity is located at the center of the bottom of the cylinder barrel, and a hollow cavity extending downwards through the transmission cavity is located at the center of the top of the cylinder barrel. A servo motor is fixedly connected to the bottom of the cylinder barrel, and the transmission shaft of the servo motor extends upwards into the transmission cavity. A radially rotatable bearing seat is located within the transmission cavity, and a coupling is located at the bottom of the bearing seat. The bearing seat is connected to the transmission shaft via the coupling, and the servo motor can drive the bearing seat to rotate via the coupling. A ball screw is located at the center of the hollow cavity along its height direction, and the lower end of the ball screw is fixedly connected to the bearing seat, allowing the bearing seat to drive the ball screw to rotate synchronously. A ball nut with threaded engagement is located outside the ball screw, and rotation of the ball screw can drive the ball nut to move linearly along its axial direction. A push rod is fixedly connected to the ball nut, and the push rod is coaxially arranged with the ball screw, its top extending above the top of the cylinder barrel. A connector is fixedly connected to the upper end of the push rod.
[0008] Furthermore, a guide seat is provided at the top of the cylinder, and a cover plate is provided at the top of the guide seat to fix it to the cylinder; a guide limiting hole with vertical communication is provided at the center of the cover plate and the guide seat, and the push rod passes through the guide limiting hole and slides with the guide limiting hole.
[0009] Furthermore, the push rod has a radial limiting surface along its length, which has two sides and is symmetrically arranged with the axis of the push rod as the center. The end face shape of the guide limiting hole matches the cross-sectional shape of the push rod.
[0010] Furthermore, a dustproof sealing ring is provided between the guide seat and the push rod, and the dustproof sealing ring is fixed inside the guide seat.
[0011] Furthermore, the bottom center of the push rod is provided with a nut connection hole that fits into the ball nut, and the top center is provided with a screw connection hole that connects to the bottom nut connection hole. The diameter of the screw connection hole is larger than the outer diameter of the ball screw.
[0012] Furthermore, the bearing housing and the cylinder are movably connected by a bearing, the bearing is sleeved on the outside of the bearing housing, and the outer ring of the bearing is embedded in the transmission cavity.
[0013] Furthermore, a round nut is provided at the upper end of the bearing housing for threaded connection with the nut, and a threaded limiting sleeve with clearance fit is fitted at the lower end of the bearing housing. The threaded limiting sleeve is threadedly connected to the cylinder.
[0014] Furthermore, the cylinder barrel is provided with an integrally formed fixed connection part, and the fixed connection part is provided with a threaded connection hole.
[0015] Furthermore, the outer side of the cylinder is provided with heat dissipation holes that communicate with the hollow cavity.
[0016] Furthermore, a limiting nut is provided at the lower end of the ball screw for threaded connection.
[0017] Compared with the prior art, the advantages of this utility model are: this resistance spot welding C-type direct drive electric cylinder uses a servo motor to directly drive the ball screw to rotate. The ball screw converts the radial rotation into the linear motion of the push rod, resulting in a high transmission conversion rate and high motion accuracy of the push rod. This ensures the positional accuracy during electrode welding and guarantees the processing quality of the product. Furthermore, the servo motor and cylinder are combined into one unit, making maintenance convenient, saving installation space, expanding the application range, reducing usage and maintenance costs, and facilitating widespread application. Attached Figure Description
[0018] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this utility model and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.
[0019] Figure 1 This is a three-dimensional structural diagram of a C-type direct-drive electric cylinder for resistance spot welding according to this utility model;
[0020] Figure 2 This is a top view schematic diagram of a C-type direct-drive electric cylinder for resistance spot welding according to this utility model;
[0021] Figure 3 yes Figure 2 Structural cross-sectional view of AA;
[0022] Figure 4 This is a schematic diagram of the cross-sectional structure of the guide seat in a C-type direct-drive electric cylinder for resistance spot welding according to this utility model.
[0023] In the diagram: 1. Servo motor; 11. Drive shaft; 2. Cylinder; 21. Fixed connection part; 211. Threaded connection hole; 22. Hollow cavity; 221. Heat dissipation hole; 23. Transmission cavity; 3. Guide seat; 31. Cover plate; 32. Guide limit hole; 33. Dustproof sealing ring; 4. Push rod; 41. Radial limit surface; 42. Screw connection hole; 43. Nut connection hole; 5. Joint; 6. Coupling; 7. Bearing seat; 71. Bearing; 72. Round nut; 73. Threaded limit sleeve; 74. Limit block; 8. Ball screw; 81. Ball nut; 82. Limit nut. Detailed Implementation
[0024] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. The components of the embodiments of this utility model described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.
[0025] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention. It should be noted that similar reference numerals and letters in the following drawings denote similar items; therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings. In the description of the embodiments of the present invention, it should be noted that if terms such as "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer" indicate orientation or positional relationships based on the orientation or positional relationships shown in the drawings, or the orientation or positional relationships commonly used when the product of the present invention is in use, they are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention. Furthermore, the terms "first," "second," etc., are used only to distinguish descriptions and should not be interpreted as indicating or implying relative importance.
[0026] Furthermore, the use of terms such as "horizontal" or "vertical" does not imply that the component must be absolutely horizontal or vertical, but rather that it can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure or component must be completely horizontal, but can be slightly tilted.
[0027] In the description of the embodiments of this utility model, "a plurality of" means at least two.
[0028] In the description of the embodiments of this utility model, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.
[0029] Example:
[0030] Please refer to the instruction manual attached. Figures 1 to 3 As shown, the instruction manual is attached. Figures 1 to 3 The image shows a C-type direct-drive electric cylinder for resistance spot welding, used for moving the electrode post in a C-type welding clamp with high positioning accuracy. In this embodiment, the C-type direct-drive electric cylinder for resistance spot welding includes a cylinder barrel 2, which has a columnar structure. To facilitate installation and connection, a fixed connection part 21 integrally formed with the cylinder barrel 2 is provided on its exterior. At least one surface of the fixed connection part 21 is flat for easy installation and connection. Furthermore, to facilitate installation and connection, a threaded connection hole 211 is provided on the fixed connection part 21. On the plane, bolts facilitate the subsequent fixed connection between the sleeve 2 and other components; a transmission cavity 23 is provided at the bottom center of the cylinder 2, and a hollow cavity 22 extending downward through the transmission cavity 23 is provided at the top center. To facilitate the dissipation of heat generated during the operation of the resistance spot welding C-type direct drive electric cylinder of this utility model without affecting the performance of internal components, heat dissipation holes 221 communicating with the hollow cavity 22 are provided on the outer side of the cylinder 2. There are multiple heat dissipation holes 221, which are arranged in a circular array with the axis of the cylinder 2 as the center; see the appendix of the specification. Figure 1 and 3As shown, a servo motor 1 is fixedly connected to the bottom of the cylinder 2. The servo motor 1 and the bottom of the cylinder 2 are fixed together by bolts to form a whole, which is convenient for disassembly and assembly. The drive shaft 11 of the servo motor 1 extends upward into the transmission cavity 23. A radially rotatable bearing seat 7 is provided in the transmission cavity 23. In order to facilitate the radial rotation of the bearing seat 7 relative to the cylinder 2, the bearing seat 7 and the cylinder 2 are movably connected by a bearing 71. The bearing 71 is sleeved on the outside of the bearing seat 7, and the outer ring of the bearing 71 is embedded in the transmission cavity 23. In order to ensure the stability of the radial rotation of the bearing seat 7, there are two bearings 71, which are sleeved on the outside of the bearing seat 7. In order to limit the position of the bearing 71 on the bearing seat 7, a round nut 72 is provided on the bearing seat 7 at the upper end of the top bearing 71, which is threaded to it. The bottom of the round nut 72 The bearing seat 7 has a threaded limiting sleeve 73 fitted onto the lower end of the lower bearing 71, with its top surface abutting against the outer circumferential surface of the inner ring of the upper bearing 71. The two bearings 71 on the bearing seat 7 are positioned by the round nut and the threaded limiting sleeve 73. An outer nut is provided on the outside of the threaded limiting sleeve 73. An internal thread is provided near the lower end of the transmission cavity 23. The threaded limiting sleeve 73 is screwed into the transmission cavity 23 and threadedly connected to the cylinder 2. To prevent the threaded limiting sleeve 73 from loosening, a limiting hole with internal and external communication is provided on the outer side of the guide seat 3. The limiting hole corresponds horizontally to the bottom of the threaded limiting sleeve 73 installed in the transmission cavity 23. A limiting block 74 is provided in the limiting hole, with its head inserted into the limiting hole and extending beyond the threaded limiting sleeve 73. Below the bottom, the bottom surface of the threaded limiting sleeve 73 is defined. The outside of the limiting block 74 is fixedly connected to the sleeve 2 by screws. A coupling 6 is provided at the bottom of the bearing seat 7. The bearing seat 7 is connected to the transmission shaft 11 through the coupling 6. The servo motor 1 can drive the bearing seat 7 to rotate through the coupling 6. The coupling 6 drives the bearing seat 7, which is fixedly connected to it, to rotate synchronously.A ball screw 8 is disposed at the center of the hollow cavity 22 along its height direction. The lower end of the ball screw 8 is fixedly connected to the bearing seat 7. Specifically, the bearing seat 7 has a connecting hole at the bottom center and a connecting hole at the top that extends downward through the connecting hole. The diameter of the connecting hole is smaller than the diameter of the bearing seat 7. The lower end of the ball screw 8 is sleeved with the connecting hole. The lower end of the ball screw 8 extends through the connecting hole on the bearing seat 7 and into the connecting hole. The portion of the ball screw 8 near the lower end has an external thread. A limiting nut 82 that engages with the thread is disposed on the portion of the ball screw 8 that passes through the connecting hole on the bearing seat 7 and enters the connecting hole. The diameter of the section of the ball screw 8 connected to the ball nut 81 is smaller than the main body diameter of the ball screw 8. The portion of the ball screw 8 near the lower end is connected to the ball nut 82. The bearing housing 7 is fixedly connected to the bearing spool 8, which can drive the ball screw 8 to rotate synchronously. A ball nut 81 with a threaded engagement is provided on the outside of the ball screw 8. Rotation of the ball screw 8 drives the ball nut 81 to move linearly along its axial direction. A push rod 4 is fixedly connected to the outside of the ball nut 81. The push rod 4 is coaxial with the ball screw 8, and its top extends above the top of the cylinder 2. To facilitate the connection between the lower end of the push rod 4 and the ball nut 81, a nut connection hole 43 is provided at the center of the bottom of the push rod 4, which engages with the ball nut 81. The lower end of the push rod 4 is fitted onto the outside of the ball nut 81 through the nut connection hole 43, forming a tight fit. They are fixedly connected together by a horizontally arranged screw. A screw connection hole 42 is provided at the center of the top of the push rod 4, with its bottom communicating with the nut connection hole 43. The diameter is larger than the outer diameter of the ball screw 8, and the upper end of the ball screw 8 can extend into the screw connection hole 42 to ensure that the push rod 4 is not interfered with by the ball screw 8 when it moves up and down. In order to limit the stability of the axial movement of the push rod 4 and maintain the straightness of the movement, a guide seat 3 is provided on the top of the cylinder 2, and a cover plate 31 is provided on the top of the guide seat 3 to fix it to the cylinder 2. The center of the cover plate 31 and the guide seat 3 is provided with a guide limiting hole 32 that is connected vertically. The push rod 4 passes through the guide limiting hole 32 and slides in the guide limiting hole 32. The cover plate 31, the guide seat 3 and the cylinder 2 are provided with threaded connection holes that are connected vertically. The cover plate 31 and the guide seat 3 are fixedly connected to the cylinder 2 by bolts passing through the threaded connection holes. In order to limit the radial position of the push rod 4 and prevent its radial rotation from causing inaccurate position deviation, please refer to the appendix of the instruction manual. Figure 4As shown, a radial limiting surface 41 is provided on the side of the push rod 4 along its length. The radial limiting surface 41 has two sides and is symmetrically arranged with the axis of the push rod 4 as the center. The end face shape of the guide limiting hole 32 matches the cross-sectional shape of the push rod 4. The radial limiting surface 41 can limit the radial position of the push rod 4, ensuring the accuracy of the push rod 4's movement. In order to automatically remove dust adhering to the outside of the push rod 4, a dustproof sealing ring 33 is provided between the guide seat 3 and the push rod 4. A sealing groove is provided on the inner wall of the guide limiting hole 32 of the guide seat 3. The dustproof sealing ring 33 is fixed in the sealing groove of the guide seat 3 and sleeved on the outside of the push rod 4. In order to facilitate the connection of the electrode, a connector 5 is provided at the upper end of the push rod 4 and is fixedly connected thereto. The connector 5 is threadedly connected to the upper end of the lead screw connection hole 42.
[0031] During operation, the servo motor 1 drives the coupling 6 to rotate forward or backward via the transmission shaft 11. The coupling 6 drives the bearing seat 7 to rotate synchronously, and the bearing seat 7 drives the ball screw 8 fixedly connected to it to rotate synchronously. When the ball screw 8 rotates, it can drive the ball nut 81 outside it to move upward or downward along its axis. The ball nut 81 drives the push rod 4 connected to it to move synchronously. The radial position of the push rod 4 is limited by the guide limiting hole 32 to ensure the straightness of its movement, thereby ensuring the positional accuracy of the axial movement of the push rod 4, and further ensuring the movement accuracy of the electrode connected to the end connector 5 of the push rod 4.
[0032] This C-type direct-drive electric cylinder for resistance spot welding uses a servo motor 1 to directly drive the ball screw 8 to rotate. The ball screw 8 converts the radial rotation into the linear motion of the push rod 4. The transmission conversion rate is high, and the motion accuracy of the push rod 4 is also very high, which ensures the positional accuracy during electrode welding and guarantees the processing quality of the product. Furthermore, the servo motor 1 and the cylinder 2 are combined into one unit, which is convenient for maintenance, saves installation space, has a wider range of applications, reduces the cost of use and maintenance, and facilitates promotion and application.
[0033] It should be emphasized that the above are merely preferred embodiments of this utility model and are not intended to limit the scope of this utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this utility model should be included within the protection scope of this utility model.
Claims
1. A C-type direct drive electric cylinder for resistance spot welding, characterized by: The cylinder (2) includes a cylinder barrel (2), with a transmission cavity (23) at the bottom center and a hollow cavity (22) extending downward through the transmission cavity (23) at the top center; a servo motor (1) is fixedly connected to the bottom of the cylinder barrel (2), and the transmission shaft (11) of the servo motor (1) extends upward into the transmission cavity (23); a radially rotatable bearing seat (7) is provided in the transmission cavity (23), and a coupling (6) is provided at the bottom of the bearing seat (7). The bearing seat (7) is connected to the transmission shaft (11) via the coupling (6), and the servo motor (1) can drive the bearing seat (7) to rotate via the coupling (6); the hollow cavity (22) A ball screw (8) is provided at the center along its height direction. The lower end of the ball screw (8) is fixedly connected to the bearing seat (7). The bearing seat (7) can drive the ball screw (8) to rotate synchronously. A ball nut (81) with its thread is provided on the outside of the ball screw (8). The rotation of the ball screw (8) can drive the ball nut (81) to move linearly along its axial direction. A push rod (4) is fixedly connected to the outside of the ball nut (81). The push rod (4) is coaxially arranged with the ball screw (8). Its top extends above the top of the cylinder (2). A connector (5) is fixedly connected to the upper end of the push rod (4).
2. The electric resistance spot welding C-type direct drive electric cylinder according to claim 1, characterized in that: The top of the cylinder (2) is provided with a guide seat (3), and the top of the guide seat (3) is provided with a cover plate (31) that is fixedly connected to the cylinder (2); the center of the cover plate (31) and the guide seat (3) is provided with a guide limiting hole (32) that is connected vertically; the push rod (4) passes through the guide limiting hole (32) and slides with the guide limiting hole (32).
3. The electric resistance spot welding C-type direct drive electric cylinder according to claim 2, characterized in that: The radial limiting surface (41) is provided on the side of the push rod (4) along its length direction. The radial limiting surface (41) has two sides and is symmetrically arranged with the axis of the push rod (4) as the center. The end face shape of the guide limiting hole (32) matches the cross-sectional shape of the push rod (4).
4. The electric resistance spot welding C-type direct drive electric cylinder according to claim 2, characterized in that: A dustproof sealing ring (33) is provided between the guide seat (3) and the push rod (4), and the dustproof sealing ring (33) is fixed inside the guide seat (3).
5. The electric resistance spot welding C-type direct drive electric cylinder according to claim 1, characterized in that: The bottom center of the push rod (4) is provided with a nut connection hole (43) that fits with the ball nut (81), and the top center is provided with a screw connection hole (42) that connects to the bottom nut connection hole (43). The diameter of the screw connection hole (42) is larger than the outer diameter of the ball screw (8).
6. The electric resistance spot welding C-type direct drive electric cylinder according to claim 1, characterized in that: The bearing housing (7) and the cylinder (2) are movably connected by a bearing (71). The bearing (71) is sleeved on the outside of the bearing housing (7), and the outer ring of the bearing (71) is embedded in the transmission cavity (23).
7. The electric resistance spot welding C-type direct drive electric cylinder according to claim 6, characterized in that: A round nut (72) is provided on the bearing housing (7) at the upper end of the bearing (71) and is threadedly connected to it. A threaded limiting sleeve (73) with clearance fit is fitted on the lower end of the bearing (71). The threaded limiting sleeve (73) is threadedly connected to the cylinder (2).
8. The electric resistance spot welding C-type direct drive electric cylinder according to claim 1, characterized in that: The cylinder (2) is externally provided with a fixed connecting part (21) integrally formed with the cylinder (2), and the fixed connecting part (21) is provided with a threaded connecting hole (211).
9. The electric resistance spot welding C-type direct drive electric cylinder according to claim 1, characterized in that: The cylinder (2) is externally provided with a heat dissipation hole (221) in communication with the hollow cavity (22).
10. The electric resistance spot welding C-type direct drive electric cylinder according to claim 1, characterized in that: The lower end of the ball screw (8) is provided with a limiting nut (82) threadedly connected with the ball screw (8).