Parallel seam welding fixture and process method capable of realizing high-precision positioning of cover plate

Abstract

The application belongs to the technical field of packaging and discloses a parallel seam welding clamp capable of realizing high-precision positioning of a cover plate and a process method, which comprises a parallel seam welding base (1) and a positioning clamp (2); a shallow cavity matched with the size of a shell (3) is processed on the parallel seam welding base (1) to play the role of accurately fixing the shell (3); the parallel seam welding base (1) is used for fixing and mounting the shell (3) on a parallel seam welding machine; the positioning clamp (2) is arranged above the shallow cavity of the parallel seam welding base (1); a notch is arranged on the positioning clamp (2), and the side wall of the notch of the positioning clamp (2) is arranged as an inclined surface; the position of the notch corresponds to the position of the shallow cavity of the parallel seam welding base (1). When the parallel seam welding is performed, the cover plate is simultaneously aligned with the shell in the X and Y directions and is in the central position, the alignment accuracy is better than 0.05 mm, the quality consistency of the parallel seam welding is good, and the sealing welding reliability is higher.

Description

Technical Field

[0001] This invention belongs to the field of packaging technology, and in particular relates to a parallel seam welding fixture and process method that can achieve high-precision positioning of cover plates. Background Technology

[0002] Parallel seam welding is a common process for high-reliability hermetic sealing of semiconductor devices. It offers advantages such as low overall temperature rise, short duration of temperature rise, good sealing performance, and high reliability, and is widely used in high-reliability hermetic sealing of semiconductor devices in military, aerospace, and other fields. To reduce production costs and improve the reliability of sealing welding, a sealing pass rate of over 99.8% is generally required, which places high demands on the dimensional accuracy of the cover plate and the welding positioning accuracy.

[0003] When using manual parallel seam welding, the cover plate and the shell are easily assembled manually, which can easily cause large assembly errors. The cover plate is prone to being biased to one side or corner, resulting in discontinuous welds and air leakage. If an automatic parallel seam welding method is used, the assembly accuracy of the cover plate can be greatly improved by image alignment and robotic arm handling. However, the equipment cost is greatly increased. At present, parallel seam welding of devices in military and other fields mainly adopts manual parallel seam welding method.

[0004] To achieve automatic alignment during parallel seam welding of the cover plate, it is typically machined into a stepped structure. The raised section formed by the step fits into the shell or sealing ring and its inner wall to achieve positioning. The raised section thickness is 0.2-0.4 mm, the weld edge thickness is 0.08-0.12 mm, and the cover plate size is 0.1-0.2 mm smaller than the shell or welding ring size. The raised section is machined using chemical etching, and its bottom is rounded. Considering the yield rate and compatibility with the shell, the raised section size will be at least 0.4 mm smaller than the inner wall of the shell or sealing ring. During the welding process, the electrode wheel rolling on the cover plate generates friction, causing the cover plate to move. This can easily cause the cover plate to deviate from its sealing position, resulting in large quality fluctuations in the parallel seam weld, reduced yield, or poor sealing performance. Summary of the Invention

[0005] The purpose of this invention is to provide a parallel seam welding fixture and process method that can achieve high-precision positioning of the cover plate, so as to solve the technical problem of poor weld quality caused by cover plate misalignment in parallel seam welding.

[0006] To achieve the above objectives, the specific technical solution of the parallel seam welding fixture and process method for achieving high-precision positioning of the cover plate according to the present invention is as follows:

[0007] A parallel seam welding fixture for high-precision positioning of a cover plate includes a parallel seam welding base 1 and a positioning fixture 2. The parallel seam welding base 1 has a shallow cavity that matches the size of a housing 3, serving to precisely fix the housing 3. The parallel seam welding base 1 is used to fix and install the housing 3 on a parallel seam welding machine. The positioning fixture 2 is positioned above the shallow cavity of the parallel seam welding base 1. The positioning fixture 2 has a notch to avoid the electrode wheel and to accommodate the cover plate 4. The sidewall of the notch in the positioning fixture 2 is set as an inclined surface. The position of the notch corresponds to the position of the shallow cavity of the parallel seam welding base 1.

[0008] Furthermore, the notch of the positioning fixture 2 is also machined with a right-angle clearance hole.

[0009] Furthermore, the shallow cavity of the parallel seam welded base 1 is 0.01-0.03 mm larger than that of the shell 3.

[0010] Furthermore, the angle of the inclined plane is 70°.

[0011] Furthermore, the depth of the shallow cavity of the parallel seam welded base 1 is 0.5-1mm.

[0012] Furthermore, the parallel seam welding base 1 is provided with two pin holes for cooperating with the parallel seam welding equipment.

[0013] This invention also provides a parallel seam welding process method for achieving high-precision positioning of a cover plate. This method is based on the parallel seam welding fixture for achieving high-precision positioning of a cover plate as described in claim 6, and includes the following steps:

[0014] S1. Place the shell 3 to be welded into the shallow cavity of the parallel seam welding base 1, and then place the cover plate 4 on the welding surface of the shell 3.

[0015] S2. Place the positioning fixture 2 on the parallel seam weld base 1, so that the two inclined walls of the positioning fixture 2 simultaneously contact the edge of the housing from the X and Y directions, and simultaneously push the cover plate on the parallel seam weld base 1 to contact the two inclined walls of the positioning fixture. This ensures that the cover plate is aligned with the housing in the X and Y directions at the same time, and the cover plate 4 is moved back about 0.05mm from the outer walls of the housing 3 in the X and Y directions at the same time.

[0016] S3. Operate the parallel seam welding machine to control the electrode wheel to descend and complete the spot welding of the cover plate 4;

[0017] S4. Slide the positioning clamp 2 away in the direction opposite to the contact surface with the cover plate 4;

[0018] S5. Operate the parallel seam welding machine to perform roll welding on the four sides of the cover plate 4 to complete the seam welding process.

[0019] The parallel seam welding fixture and process method for achieving high-precision positioning of the cover plate of the present invention have the following advantages: during parallel seam welding, the cover plate 4 is simultaneously aligned with the shell 3 in the X and Y directions and is in the center position, with an alignment accuracy better than 0.05mm, good quality consistency of parallel seam welding, and higher reliability of sealing welding. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the parallel seam welding fixture structure for achieving high-precision positioning of the cover plate according to the present invention;

[0021] Figure 2 This is a schematic diagram of the parallel seam welded base structure;

[0022] Figure 3 This is a schematic diagram of the positioning fixture structure. Detailed Implementation

[0023] To better understand the purpose, structure, and function of this invention, the following detailed description, in conjunction with the accompanying drawings, provides a parallel seam welding fixture and process method for achieving high-precision positioning of a cover plate.

[0024] like Figures 1-3 As shown, the parallel seam welding fixture for high-precision positioning of the cover plate in this embodiment includes a parallel seam welding base 1 and a positioning fixture 2. The parallel seam welding base 1 is used to fix and install the housing 3 on the parallel seam welding machine. The positioning fixture 2 is set above the parallel seam welding base 1 and is used to position the cover plate 4 with high precision.

[0025] The parallel seam welding base 1 has a shallow cavity that matches the size of the shell 3, which serves to precisely fix the shell 3. The cavity is 0.5-1mm deep and 0.01-0.03mm larger than the shell 3. The two pin holes on the parallel seam welding base 1 are used to cooperate with the parallel seam welding equipment.

[0026] The two side walls of the positioning fixture 2 that contact the cover plate 4 are inclined surfaces, used to control the distance between the cover plate 4 and the outer wall of the housing 3. The inclined surface angle θ is preferably 70°, ensuring that the cover plate 4 retracts by approximately 0.05mm in both the X and Y directions relative to the outer walls of the housing 3. The positioning fixture 2 is also machined with a clearance electrode wheel and a notch for pushing the cover plate. This serves two purposes: first, it does not affect the spot welding of the electrode wheel; second, it ensures that the cover plate can fit tightly against the inclined surface of the positioning fixture when placed on the welding surface of the housing. The positioning fixture 2 is also machined with a right-angle clearance hole to prevent the inclined wall of the fixture from not fitting tightly against the housing and the cover plate. The width A and depth B of the notch in the positioning fixture 2 are approximately 3mm greater than the length and width of the housing, which facilitates that when the positioning fixture is slid away in the opposite direction to the contact surface after the cover plate is spot welded, it does not affect the position of the housing.

[0027] This embodiment also provides a parallel seam welding process method that can achieve high-precision positioning of the cover plate, including the following steps:

[0028] S1. Place the shell 3 to be welded into the shallow cavity of the parallel seam welding base 1, and then place the cover plate 4 on the welding surface of the shell 3.

[0029] S2. Place the positioning fixture 2 on the parallel seam weld base 1, so that the two inclined walls of the positioning fixture 2 simultaneously contact the edge of the housing from the X and Y directions, and simultaneously push the cover plate on the parallel seam weld base 1 to contact the two inclined walls of the positioning fixture. This ensures that the cover plate is aligned with the housing in the X and Y directions at the same time, and the cover plate 4 is moved back about 0.05mm from the outer walls of the housing 3 in the X and Y directions at the same time.

[0030] S3. Operate the parallel seam welding machine to control the electrode wheel to descend and complete the spot welding of the cover plate 4;

[0031] S4. Slide the positioning clamp 2 away in the direction opposite to the contact surface with the cover plate 4;

[0032] S5. Operate the parallel seam welding machine to perform roll welding on the four sides of the cover plate 4 to complete the seam welding process.

[0033] By adopting this invention, the cover plate 4 can be aligned with the shell 3 in both the X and Y directions during parallel seam welding, and the cover plate 4 can be centered. The alignment accuracy is better than 0.05mm, the quality consistency of parallel seam welding is good, and the reliability of sealing welding is higher.

[0034] Although embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art will be able to make various modifications and improvements without departing from the principles of the present invention, and these modifications and improvements should also be considered to fall within the scope of protection of the present invention.

Claims

1. A parallel seam welding fixture capable of achieving high-precision positioning of a cover plate, characterized in that, The system includes a parallel seam welding base (1) and a positioning fixture (2). The parallel seam welding base (1) has a shallow cavity that matches the size of the housing (3) to precisely fix the housing (3). The parallel seam welding base (1) is used to fix the housing (3) and install it on the parallel seam welding machine. The positioning fixture (2) is set above the shallow cavity of the parallel seam welding base (1). The positioning fixture (2) has a notch to avoid the electrode wheel and accommodate the cover plate (4). The side wall of the notch of the positioning fixture (2) is set as a slope. The slope is used to simultaneously contact the edge of the housing from the X and Y directions when the positioning fixture is placed on the parallel seam welding base (1) and push the cover plate so that the cover plate is aligned with the housing in the X and Y directions. The position of the notch corresponds to the position of the shallow cavity of the parallel seam welding base (1).

2. The parallel seam welding fixture for high-precision positioning of the cover plate according to claim 1, characterized in that, The positioning fixture (2) also has a right-angle clearance hole machined in the notch.

3. The parallel seam welding fixture for high-precision positioning of the cover plate according to claim 2, characterized in that, The shallow cavity of the parallel seam welded base (1) is 0.01-0.03 mm larger than that of the shell (3).

4. The parallel seam welding fixture for high-precision positioning of the cover plate according to claim 3, characterized in that, The angle of the inclined plane is 70°.

5. The parallel seam welding fixture for high-precision positioning of the cover plate according to claim 4, characterized in that, The shallow cavity of the parallel seam welded base (1) has a depth of 0.5-1mm.

6. The parallel seam welding fixture for high-precision positioning of the cover plate according to claim 5, characterized in that, The parallel seam welding base (1) is provided with two pin holes for use with parallel seam welding equipment.

7. A parallel seam welding process method for achieving high-precision positioning of cover plates, characterized in that, This method is based on the parallel seam welding fixture described in claim 6, which enables high-precision positioning of the cover plate, and includes the following steps: S1. Place the shell (3) to be welded into the shallow cavity of the parallel seam welding base (1), and then place the cover plate (4) on the welding surface of the shell (3); S2. Place the positioning fixture (2) on the parallel seam weld base (1) so that the two inclined walls of the positioning fixture (2) simultaneously contact the edge of the shell from the X and Y directions, and simultaneously push the cover plate on the parallel seam weld base (1) to contact the two inclined walls of the positioning fixture. This ensures that the cover plate is aligned with the shell in the X and Y directions at the same time, and the cover plate (4) moves back about 0.05mm from the outer walls of the shell (3) in the X and Y directions at the same time. S3. Operate the parallel seam welding machine to control the electrode wheel to descend and complete the spot welding of the cover plate (4); S4. Slide the positioning clamp (2) away in the opposite direction to the contact surface of the cover plate (4); S5. Operate the parallel seam welding machine to perform roll welding on the four sides of the cover plate (4) to complete the seam welding process.

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