Positioning jig with preset gold-tin cover plate

Abstract

The utility model relates to the technical field of chip packaging, and discloses a positioning jig of a preset gold-tin cover plate, which comprises a limiting plate, the bottom of the limiting plate is fixedly connected with a cavity plate, and the bottom of the cavity plate is fixedly connected with a bottom plate. Threaded holes are formed in the surface of the edge part of the limiting plate, threaded holes are formed in the surface of the edge part of the cavity plate, the number of the threaded holes is eight, and the threaded holes of the cavity plate and the threaded holes of the limiting plate coincide in position. Cavity grooves are formed in the surface of the cavity plate, and the number of the cavity grooves is eighteen. The jig is simple and reliable in structure, convenient to machine, low in cost and short in period, the longitudinal dimensional deviation between the Kovar cover plate and the preformed soldering lug and the angle deviation between the Kovar cover plate and the preformed soldering lug are greatly reduced through the jig, the alignment qualification rate exceeds 99%, and the actual using effect is economical, practical and good in stability.

Description

Technical Field

[0001] The utility model relates to the technical field of positioning jigs, in particular to a positioning jig for pre-setting a gold-tin cover plate. Background Art

[0002] The pre-set gold-tin cover is to precisely position and spot-weld the gold-tin preformed solder sheet and fix it on the alloy cover, which simplifies the packaging process. This product has been widely used in the hermetic packaging of microwave radio frequency modules, FPGA special circuits, MEMS devices, and optoelectronics.

[0003] Gold-tin cover plate (Kovar alloy) welding, package cover plate welding pre-welding process: The cover plate (Kovar alloy) and solder (gold-tin alloy) are spot welded through a precise intelligent spot welding process, with one point welded at each of the four corners, for a total of four points, to achieve the positioning and pre-setting of the gold-plated cover plate and the gold-tin solder preformed solder sheet. The realization of this process requires precise welding energy control equipment, and a complete set of pressure mechanisms and positioning mechanisms. On the one hand, it solves the problem of alignment between the two, and on the other hand, the two are firmly combined.

[0004] The process requires that the position accuracy between the general alloy cover plate and the gold-tin preformed solder sheet is ±0.1mm, that is, the misalignment cannot exceed 0.1mm. This invention solves the alignment problem in the mass production of pre-set gold-tin cover plates, and achieves a position accuracy pass rate of more than 99% during use. Utility Model Content

[0005] 1. Technical issues to be resolved

[0006] In view of the deficiencies of the prior art, the utility model provides a positioning fixture for pre-setting a gold-tin cover plate.

[0007] (II) Technical solution

[0008] To achieve the above purpose, the utility model provides the following technical solution: a positioning fixture for pre-setting a gold-tin cover plate, comprising a limit plate, the bottom of which is fixedly connected to a cavity plate, and the bottom of which is fixedly connected to a bottom plate. By setting the limit plate, the top block can be stuck in the cavity groove.

[0009] Preferably, the edge surface of the limiting plate is provided with threaded holes, and the edge surface of the cavity plate is provided with threaded holes, the number of the threaded holes is eight, and the positions of the threaded holes of the cavity plate and the limiting plate overlap with each other. By providing threaded holes at the edge positions of the limiting plate and the cavity plate, the cavity plate, the limiting plate and the bottom plate can be screwed together, and by providing eight threaded holes, the cavity plate and the limiting plate can be more firmly connected together.

[0010] Preferably, the surface of the cavity plate is provided with cavity grooves, the number of the cavity grooves is eighteen, and the inner wall of the cavity groove is fixedly connected with a spring. By providing the cavity grooves, the top block and the cover plate can be limited.

[0011] Preferably, one end of the spring away from the inner wall of the cavity groove is fixedly connected with a top block, and the outer shape of the top block is L-shaped. By arranging the spring, the spring can exert a thrust on the top block to move it forward.

[0012] Preferably, one end of the top block is fixedly connected to a cover plate, the outer wall of the top block is slidably connected to the cavity groove, and the outer wall of the top block is in contact with a limiting strip of the limiting plate.

[0013] Preferably, a welding ring is fixedly mounted on the outer wall of the cover plate, and the shape and size of the cover plate and the welding ring are adapted to the cavity groove. By arranging the cover plate and the welding ring with adapted sizes, the cover plate and the welding ring can be exactly placed in the cavity groove.

[0014] (III) Beneficial effects

[0015] Compared with the prior art, the utility model provides a positioning fixture for pre-setting chip packaging, which has the following beneficial effects:

[0016] 1. A positioning fixture for pre-setting the gold-tin cover plate, by opening eight threaded holes on the edge parts of the limit plate and the cavity plate, and then screwing screws in the threaded holes, the limit plate and the cavity plate can be firmly fixed on the bottom plate, by setting the limit plate and the L-shaped top block, the limit strip on the limit plate can clamp the top block in the cavity plate to prevent it from falling off, and by setting the cavity plate and opening the cavity groove on the surface of the cavity plate, a limit and placement space can be provided for the cover plate and the welding ring.

[0017] 2. This positioning fixture for pre-set gold-tin cover plate can make the top block be pushed forward by the thrust of the spring by setting a spring, so that the welding plate and welding ring are pushed to the inner wall of the groove to complete the limit and fixation. The fixture structure is simple and reliable, easy to process, low cost, short cycle, and the fixture greatly reduces the longitudinal size deviation between the Kovar cover plate and the preformed welding sheet, as well as the angular deviation between the Kovar cover plate and the preformed welding sheet. The alignment pass rate exceeds 99%, and the actual use effect is economical, practical and stable. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0019] Figure 1 This is a main stereoscopic view of the utility model;

[0020] Figure 2 It is a detailed structural diagram of the utility model;

[0021] Figure 3 This is a schematic diagram of the top block of the utility model;

[0022] Figure 4 It is a schematic diagram of the welding ring of the utility model.

[0023] In the figure: 1. limit plate; 2. cavity plate; 3. top block; 4. spring; 5. cover plate; 6. welding ring; 7. bottom plate. DETAILED DESCRIPTION

[0024] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments.

[0025] Example 1

[0026] like Figure 1-4 As shown, the utility model provides a positioning fixture for pre-setting a gold-tin cover plate, including a limit plate 1, a cavity plate 2 is fixedly connected to the bottom of the limit plate 1, and a bottom plate 7 is fixedly connected to the bottom of the cavity plate 2. By setting the limit plate 1, the top block 3 can be stuck in the cavity groove.

[0027] The edge of the limiting plate 1 is provided with threaded holes, and the edge of the cavity plate 2 is provided with threaded holes. There are eight threaded holes, and the positions of the threaded holes of the cavity plate 2 and the threaded holes of the limiting plate 1 overlap with each other. By providing threaded holes at the edge of the limiting plate 1 and the cavity plate 2, the cavity plate 2, the limiting plate 1 and the bottom plate 7 can be screwed together, and by providing eight threaded holes, the cavity plate 2 and the limiting plate 1 can be more firmly connected together.

[0028] The surface of the cavity plate 2 is provided with cavity grooves, the number of which is eighteen, and the inner wall of the cavity groove is fixedly connected with a spring 4. By providing the cavity grooves, the top block 3 and the cover plate 5 can be limited.

[0029] In this embodiment, by opening eight threaded holes on the edge portions of the limit plate 1 and the cavity plate 2 and then screwing screws into the threaded holes, the limit plate 1 and the cavity plate 2 can be firmly fixed on the base plate 7. By setting the limit plate 1 and setting the L-shaped top block 3, the limit strip on the limit plate 1 can clamp the top block 3 in the cavity plate 2 to prevent it from falling off. By setting the cavity plate 2 and opening a cavity groove on the surface of the cavity plate 2, a limiting and placement space can be provided for the cover plate 5 and the welding ring 6.

[0030] Example 2

[0031] like Figure 1-4 As shown, based on Example 1, the utility model provides a technical solution: preferably, one end of the spring 4 away from the inner wall of the cavity groove is fixedly connected to the top block 3, and the top block 3 has an L-shaped shape. By setting the spring 4, the spring 4 can exert a thrust on the top block 3 to move it forward.

[0032] One end of the top block 3 is fixedly connected with a cover plate 5 , the outer wall of the top block 3 is slidably connected to the cavity groove, and the outer wall of the top block 3 is in contact with the limiting strip of the limiting plate 1 .

[0033] The outer wall of the cover plate 5 is fixedly mounted with a welding ring 6, and the shape and size of the cover plate 5 and the welding ring 6 are adapted to the cavity groove. By arranging the cover plate and the welding ring 6 with adapted sizes, the cover plate 5 and the welding ring 6 can be exactly placed in the cavity groove.

[0034] In this embodiment, by providing the spring 4, the top block 3 can be pushed forward by the thrust of the spring 4, so that the welding plate 5 and the welding ring 6 are pushed to the inner wall of the groove to complete the limiting and fixing. The fixture has a simple and reliable structure, convenient processing, low cost, and short cycle. The fixture greatly reduces the longitudinal dimensional deviation between the Kovar cover plate 5 and the preformed welding piece, as well as the angular deviation between the Kovar cover plate 5 and the preformed welding piece. The alignment qualified rate exceeds 99%, and the actual use effect is economical, practical, and stable.

[0035] The following is a detailed description of the working principle of the positioning fixture for pre-set gold-tin cover plate.

[0036] like Figure 1-4 As shown, when in use, first use bolts to tightly connect the threaded holes on the periphery of the bottom plate 7, the cavity plate 2, and the limit plate 1. After the three are connected, install the top block 3 into the slide groove of the cavity plate 2, push it to the front, and install the spring 4. The cavity size of the cavity plate 2 where the cover plate 5 is placed in the figure is 10.05x11mm. The size of the matching cover plate 5 is 10x10mm, and the outer contour size of the welding ring 6 is 10x10mm. At this time, pull the top block 3 to the back, and then use tweezers or a vacuum suction pen to put the cover plate 5 and the welding ring 6 into the cavity groove on the cavity plate 2 in turn. Then relax the top block 3, which will be pushed forward by the force of the spring 4, and the cover plate 5 and the welding ring 6 will be pushed to the inner wall of the groove to complete the limiting and fixing. The cavity plate 2 and the limiting plate 1 in the figure are processed by CNC. The cavity plates 2 and limiting plates 1 of various sizes can be adapted to the cover plates 5 of various sizes. The theoretical maximum value of the left-right clearance of the cover plate 5 in the cavity plate 2 is equal to 10.05-10=0.05mm, which is much better than the technical standard requirements. The cavity plates 2 of other sizes are also widened by 0.05mm on the basis of the outer contour of the cover plate 5 for adaptation. The top block 3 and the spring 4 are universal parts, which are adapted to the cover plates 5 of various sizes.

Claims

1. A positioning fixture for pre-setting a gold-tin cover plate, comprising a limit plate (1), characterized in that: The bottom of the limiting plate (1) is fixedly connected to a cavity plate (2), and the bottom of the cavity plate (2) is fixedly connected to a bottom plate (7).

2. A positioning fixture for pre-setting a gold-tin cover plate according to claim 1, characterized in that: The edge surface of the limiting plate (1) is provided with threaded holes, and the edge surface of the cavity plate (2) is provided with threaded holes. The number of the threaded holes is eight, and the positions of the threaded holes of the cavity plate (2) and the threaded holes of the limiting plate (1) overlap with each other.

3. The positioning fixture for pre-setting the gold-tin cover plate according to claim 1, characterized in that: The surface of the cavity plate (2) is provided with cavity grooves, the number of which is eighteen, and the inner walls of the cavity grooves are fixedly connected with springs (4).

4. The positioning fixture for pre-setting the gold-tin cover plate according to claim 3, characterized in that: One end of the spring (4) away from the inner wall of the cavity groove is fixedly connected to a top block (3), and the top block (3) has an L-shaped appearance.

5. The positioning fixture for pre-setting the gold-tin cover plate according to claim 4, characterized in that: One end of the top block (3) is fixedly connected to a cover plate (5), the outer wall of the top block (3) is slidably connected to the cavity groove, and the outer wall of the top block (3) is in contact with the limiting strip of the limiting plate (1).

6. A positioning fixture for pre-setting the gold-tin cover plate according to claim 5, characterized in that: A welding ring (6) is fixedly mounted on the outer wall of the cover plate (5); the shape and size of the cover plate (5) and the welding ring (6) are compatible with the cavity groove.

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