Lead frame scraping device for non-welding process

Abstract

This invention discloses a non-soldering lead frame solder paste scraping device, belonging to the field of lead frame technology. The device includes a scraping box, a conveyor belt rotatably connected inside the scraping box, a scraping frame slidably connected inside the scraping box, and a template detachably connected to the bottom of the scraping frame. A slider is slidably connected inside the scraping frame, and a scraper is provided at the bottom of the slider for scraping solder paste. A pressure cylinder is fixedly connected to one side of the scraping frame and is connected to the inside of the scraping frame through a connecting pipe. A piston rod is slidably connected inside the pressure cylinder. The slider drives the scraper to move and scrape solder paste onto the lead frame. Then, the slider abuts against the piston rod, pushing the piston rod to deliver air from the pressure cylinder into the scraping frame. The air pressure applies pressure to the solder paste in the slots on the template, improving the ease of solder paste removal from the template and preventing solder paste residue in the slots on the template.

Description

Technical Field

[0001] This invention relates to the field of lead frame technology, and more specifically to a lead frame adhesive scraping device using a non-welding process. Background Technology

[0002] To improve semiconductor productivity, save raw materials, and facilitate processing, it is usually necessary to stamp the semiconductor onto copper or aluminum plates. The intermediate product obtained by stamping is the lead frame.

[0003] Existing chips are typically soldered to the corresponding node positions on the leadframe using solder paste. During soldering, the end of a probe is usually placed in a solder paste bath to adhere the solder paste to the end. The probe with solder paste is then transferred to the corresponding point on the leadframe, and the end of the probe is brought into contact with the leadframe to transfer the solder paste onto the leadframe before the core is bonded. This method suffers from missed solder points and is slow and inefficient. To improve solder paste transfer efficiency, existing technologies use a stencil with slots corresponding to the solder joints on the leadframe. Solder paste is applied to the stencil, and a scraper is used to scrape the solder paste into the slots on the stencil to connect with the solder joints on the leadframe. The stencil is then removed from the leadframe, completing the solder paste transfer in one step. However, this scraping method also has the following problems: 1) Manual scraping is labor-intensive; 2) Alignment between the leadframe and the stencil is slow, and the slots on the stencil...

[0004] 3) When the solder paste detaches from the slot in the stencil and adheres to the lead frame, some residue remains on the stencil, resulting in uneven adhesion of the solder paste to the solder joints and reducing the quality of the solder paste application. Summary of the Invention

[0005] To overcome the aforementioned technical problems, the present invention aims to provide a lead frame adhesive scraping device for a non-soldering process. The lead frame is transported to the bottom of the template by a conveyor belt, and then the scraper is moved downward by a lifting cylinder to bring the template into contact with the lead frame. The scraper is then moved by a slider to scrape solder paste onto the lead frame, thereby improving the convenience of lead frame adhesive scraping, reducing the labor intensity of manual adhesive scraping, and improving the efficiency of adhesive scraping.

[0006] The objective of this invention can be achieved through the following technical solutions:

[0007] A non-welding process lead frame adhesive scraping device includes an adhesive scraping box, a conveyor belt rotatably connected inside the adhesive scraping box, an adhesive scraping frame slidably connected inside the adhesive scraping box, a template detachably connected to the bottom of the adhesive scraping frame, a slider slidably connected inside the adhesive scraping frame, a scraper at the bottom of the slider for scraping adhesive, a pressure cylinder fixedly connected to one side of the adhesive scraping frame, the pressure cylinder communicating with the inside of the adhesive scraping frame through a connecting pipe, a piston rod slidably connected inside the pressure cylinder, one end of the piston rod passing through the pressure cylinder and the adhesive scraping frame and cooperating with the slider.

[0008] As a further embodiment of the present invention: the two ends of the conveyor belt pass through both sides of the scraper box and extend to the outside, two sets of rotating shafts are rotatably connected to both sides of the scraper box, the conveyor belt is driven and connected to the outer wall of the two sets of rotating shafts, a transmission motor is fixedly connected to one side of the outer wall of the scraper box, and the output end of the transmission motor 202 is connected to one set of the rotating shafts.

[0009] As a further aspect of the present invention: a lifting cylinder is fixedly connected to the top of the glue scraper box, and the output end of the lifting cylinder passes through the glue scraper box and is connected to the top of the glue scraper frame.

[0010] As a further aspect of the present invention: a scraping motor is fixedly connected to one side of the outer wall of the scraping frame, the output end of the scraping motor passes through the scraping frame and is fixedly connected to a lead screw, the lead screw is rotatably connected inside the scraping frame, the slider is threadedly connected to the outer wall of the lead screw, and the two ends of the slider are in contact with the inner walls on both sides of the scraping frame.

[0011] As a further aspect of the present invention: an inclined surface is provided on one side of the scraper, a glue storage cavity is provided inside the scraper, a plurality of glue outlet holes penetrating the scraper are provided on one side of the glue storage cavity, and a glue inlet pipe is fixedly connected to one side of the glue storage cavity.

[0012] As a further aspect of the present invention: two sets of fixing plates are symmetrically arranged on both sides of the glue scraper, and a trapezoidal block is fixedly connected to the bottom of the fixing plate for correcting the lead frame.

[0013] As a further aspect of the present invention: a sliding rod is slidably connected to the bottom of the slider, the scraper is fixedly connected to the bottom of the sliding rod, and a pressure spring is sleeved on the outer wall of the sliding rod, with the two ends of the pressure spring abutting against the slider and the scraper respectively.

[0014] As a further aspect of the present invention: a fixing block is fixedly connected inside the scraper, a collection groove is provided inside the fixing block, and a triangular block is fixedly connected to one side of the fixing block.

[0015] As a further embodiment of the present invention: a support plate is fixedly connected inside the glue scraper box, the top of the support plate is flush with the top surface of the conveyor belt, a positioning cylinder is fixedly connected to the bottom inner wall of the glue scraper box, and a positioning plate is fixedly connected to the output end of the positioning cylinder.

[0016] As a further aspect of the present invention: two sets of baffles are fixedly connected to the inner wall of the glue scraper box, the two sets of baffles are respectively located on both sides of the conveyor belt, the side wall of the baffle is provided with a groove, and multiple sets of guide wheels are rotatably connected inside the groove.

[0017] The beneficial effects of this invention are:

[0018] 1. In this invention, the lead frame is transported to the bottom of the template by a conveyor belt, and then the scraper is moved downward by a lifting cylinder so that the template is in contact with the lead frame. Then, the scraper is moved by a slider to scrape the solder paste onto the lead frame, which improves the convenience of scraping the lead frame, reduces the labor intensity of manual scraping, and improves the efficiency of scraping.

[0019] 2. In this invention, when the squeegee moves downward, the trapezoidal blocks on both sides of the squeegee abut against the two sides of the lead frame, pushing the lead frame to move and align with the template, thereby improving the accuracy of the solder paste application position on the lead frame.

[0020] 3. In this invention, the piston rod is pushed by the slider to slide inside the pressure cylinder, and the air in the pressure cylinder is sent into the squeegee frame, which increases the air pressure inside the squeegee frame. When the squeegee frame moves the template out of the lead frame, the air pressure pushes the solder paste out of the template, which improves the adhesion of the solder paste on the lead frame and reduces the amount of solder paste residue in the template. Attached Figure Description

[0021] The invention will now be further described with reference to the accompanying drawings.

[0022] Figure 1 This is a schematic diagram of the main structure of the present invention;

[0023] Figure 2 This is a schematic diagram of the internal structure of the glue scraper of the present invention;

[0024] Figure 3 This is a schematic diagram of the three-dimensional structure of the glue scraper frame of the present invention;

[0025] Figure 4 This is a schematic diagram of the scraper structure of the present invention;

[0026] Figure 5 This is the present invention. Figure 1 A magnified schematic diagram of the central part of the structure;

[0027] Figure 6 This is a schematic diagram of the conveyor belt structure in this invention.

[0028] In the diagram: 1. Glue scraper box; 101. Baffle; 1011. Groove; 1012. Guide wheel; 2. Conveyor belt; 201. Rotary shaft; 202. Conveyor motor; 203. Support plate; 3. Glue scraper frame; 301. Glue scraper motor; 302. Lead screw; 4. Template; 5. Slider; 501. Sliding rod; 502. Pressure spring; 6. Scraper; 601. Glue storage chamber; 602. Glue outlet hole; 603. Glue inlet pipe; 7. Pressure cylinder; 701. Connecting pipe; 702. Piston rod; 703. Return spring; 8. Connecting plate; 801. Adjusting rod; 802. Clamping plate; 9. Fixing plate; 901. Trapezoidal block; 10. Positioning cylinder; 11. Positioning plate; 12. Lifting cylinder; 13. Fixing block; 131. Collection trough; 132. Triangular block. Detailed Implementation

[0029] The following will provide a clear and complete description of the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention.

[0030] like Figures 1-6 As shown, a non-welding process for scraping glue onto a lead frame includes a scraping box 1, a conveyor belt 2 rotatably connected inside the scraping box 1 for conveying the lead frame, a scraping frame 3 slidably connected inside the scraping box 1, and a template 4 detachably connected to the bottom of the scraping frame 3; a lifting cylinder 12 is fixedly connected to the top of the scraping box 1, and the output end of the lifting cylinder 12 passes through the scraping box 1 and is connected to the top of the scraping frame 3, driving the scraping frame 3 to move up and down to contact the top of the lead frame on the conveyor belt 2.

[0031] The squeegee frame 3 has a slider 5 slidably connected inside. A squeegee motor 301 is fixedly connected to the outer wall of one side of the squeegee frame 3. The output end of the squeegee motor 301 passes through the squeegee frame 3 and is fixedly connected to a lead screw 302. The lead screw 302 is rotatably connected inside the squeegee frame 3. The slider 5 is threaded to the outer wall of the lead screw 302, and the two ends of the slider 5 are in contact with the inner walls of both sides of the squeegee frame 3 for movement. A scraper 6 is provided at the bottom of the slider 5 and moves on the template 4 to scrape the solder paste through the corresponding slots on the template 4 and the lead frame, smoothing the solder paste onto the lead frame. At the same time, a pressure cylinder 7 is fixedly connected to one side of the squeegee frame 3. The pressure cylinder 7 is connected to a connecting pipe 701. The pressure cylinder 7 is connected to the inside of the squeegee 3. A piston rod 702 is slidably connected inside the pressure cylinder 7. When the slider 5 moves, it abuts against the piston rod 702, pushing the piston rod 702 to move. The piston rod 702 sends the air in the pressure cylinder 7 into the squeegee 3 through the connecting pipe 701, which increases the air pressure in the squeegee 3. The air pressure applies pressure to the solder paste in the slot on the template 4, improving the ease with which the solder paste can be removed from the template 4 and preventing solder paste from remaining in the slot on the template 4. A return spring 703 is provided inside the pressure cylinder 7. When the squeegee 3 is separated from the template 4, the return spring 703 drives the piston rod 702 to return to its original position.

[0032] like Figure 1 As shown, in order to facilitate the transport of the lead frame, the two ends of the conveyor belt 2 pass through both sides of the glue scraper box 1 and extend to the outside to input and output the lead frame. Two sets of rotating shafts 201 are rotatably connected to both sides of the glue scraper box 1. The conveyor belt 2 is driven and connected to the outer wall of the two sets of rotating shafts 201. A transmission motor 202 is fixedly connected to one side of the outer wall of the glue scraper box 1. The output end of the transmission motor 202 is connected to a set of rotating shafts 201 to drive the conveyor belt 2 to rotate and transport the lead frame.

[0033] like Figure 2 and Figure 4 As shown, in order to facilitate the supply of solder paste, the squeegee 6 has an inclined surface on one side to retain the solder paste. The squeegee 6 has a glue storage cavity 601 inside. The glue storage cavity 601 has multiple sets of glue outlet holes 602 that penetrate the squeegee 6 on one side. A glue inlet tube 603 is fixedly connected to one side of the glue storage cavity 601 to deliver the solder paste into the glue storage cavity 601. Then, the solder paste flows out through the glue outlet holes 602 to one side of the inclined surface of the squeegee 6. When the squeegee 6 moves, the solder paste is evenly applied to the solder joints of the lead frame through the slots on the template 4.

[0034] like Figure 2 and Figure 3 As shown, in order to facilitate the alignment between the template 4 and the lead frame, two sets of symmetrical fixing plates 9 are provided on both sides of the aforementioned squeegee 3. A trapezoidal block 901 is fixedly connected to the bottom of the fixing plate 9. The inclined surfaces of the trapezoidal block 901 are used to correct the two sides of the lead frame, so that the lead frame is aligned with the template 4, thereby improving the accuracy of the solder paste application position on the lead frame.

[0035] like Figure 2 As shown, in order to improve the solder paste application effect, the bottom of the slider 5 is slidably connected to the slide rod 501, and the scraper 6 is fixedly connected to the bottom of the slide rod 501. The outer wall of the slide rod 501 is fitted with a pressure spring 502. The two ends of the pressure spring 502 abut against the slider 5 and the scraper 6 respectively. The tension of the pressure spring 502 pushes the scraper 6 to abut against the top of the template 4, so that the bottom of the scraper 6 is always in contact with the top of the template 4, avoiding wear caused by repeated scraping of the solder paste by the scraper 6, which would prevent the solder paste from being completely applied to the lead frame.

[0036] like Figure 2 and Figure 5 As shown, in order to facilitate the collection of residual solder paste on the template 4, a fixing block 13 is provided inside the aforementioned scraper 3. The fixing block 13 has a collection groove 131 inside. A triangular block 132 is fixedly connected to one side of the fixing block 13. After the scraper 6 scrapes the solder paste off the lead frame, it continues to push the solder paste to move. The solder paste is pushed onto the fixing block 13 by the inclined surface of the triangular block 132. The solder paste falls into the collection groove 131 through the top of the fixing block 13 for collection.

[0037] like Figure 1 As shown, in order to improve the accuracy of the lead frame conveying position, a support plate 203 is fixedly connected inside the glue scraper box 1. The support plate 203 is located in the middle of the conveyor belt 2, and its top is flush with the top surface of the conveyor belt 2 to support the lead frame. A positioning cylinder 10 is fixedly connected to the bottom inner wall of the glue scraper box 1. A positioning plate 11 is fixedly connected to the output end of the positioning cylinder 10. The positioning plate 11 is attached to one side of the lead frame to limit the position of the lead frame. The conveyor belt 2 is a split belt with a hollow center.

[0038] like Figure 1 and Figure 6 As shown, in order to avoid wear on the lead frame, two sets of baffles 101 are fixedly connected to the inner wall of the glue scraper box 1. The two sets of baffles 101 are located on both sides of the conveyor belt 2 to limit the lead frame conveyed on the conveyor belt 2. At the same time, the side wall of the baffle 101 is provided with a groove 1011. Multiple sets of guide wheels 1012 are rotatably connected inside the groove 1011. The guide wheels 1012 contact the two sides of the lead frame for conveying, thereby reducing the wear on the two sides of the lead frame.

[0039] like Figure 3 As shown, in order to increase the convenience of use, the present invention uses connecting plates 8 fixed on both sides of the glue scraper 3. The connecting plates 8 are threaded with adjusting rods 801. The bottom of the adjusting rods 801 is fixedly connected with clamping plates 802. The template 4 is installed and fixed by the top of the two sets of clamping plates 802 being attached to the bottom of the template 4, thereby improving the convenience of installation and disassembly.

[0040] The working principle of this invention is as follows: When using the device, the user places the lead frame onto the conveyor belt 2, then starts the conveyor motor 202 to drive the rotating shaft 201 to rotate. The rotating shaft 201 drives the conveyor belt 2 to rotate, transporting the lead frame. When the lead frame moves to the bottom of the template 4 and abuts against the positioning plate 11, the conveyor belt 2 stops. Then, the lifting cylinder 12 is activated, which drives the scraper 3 to move downwards. The inclined surfaces of the trapezoidal blocks 901 on both sides of the scraper 3 abut against the sides of the lead frame, causing the lead frame to move towards the center and align with the template 4. Then, the scraper 3 drives the bottom mold... The board 4 is attached to the top of the lead frame. Solder paste is then pumped into the storage chamber 601 through the glue inlet pipe 603 by the glue supply pump. It then flows out onto the template 4 through multiple glue outlet holes 602 on the inclined side of the scraper 6. The scraper motor 301 is then activated, driving the lead screw 302 to rotate. The slider 5, threaded to the outer wall of the lead screw 302, moves, causing the scraper 6 at the bottom to move. The scraper 6 scrapes the solder paste from the template 4 into the slots on the template 4 that match the lead frame, thus achieving solder paste application to the lead frame. The slider 5 continues to drive the scraper 6, with one end of the slider 5 connected to the piston rod 702. The piston rod 702 slides within the pressure cylinder 7, causing air to enter the squeegee 3 through the connecting pipe 701. This increases the air pressure inside the squeegee 3, making it easier for the solder paste inside the slot on the template 4 to detach from the template 4, preventing it from sticking and improving the solder paste application effect. Simultaneously, the scraper 6 moves, pushing the solder paste onto the inclined surface of the triangular block 132, and then onto the fixed block 13, where it falls into the collection groove 131, preventing solder paste from accumulating on the template 4. Then, the lifting cylinder 12 is activated again. Step 12 moves the squeegee 3 away from the lead frame. At this time, the air pressure inside the squeegee 3 pushes the solder paste in the slot of the template 4 to adhere to the lead frame, improving the integrity of the solder paste detachment. Then, the positioning cylinder 10 is started to move the positioning plate 11 downward. Then, the conveyor motor 202 is started to drive the rotating shaft 201 to rotate. The rotating shaft 201 drives the conveyor belt 2 to rotate, conveying the lead frame after squeegee application. Then, the squeegee motor 301 is started to drive the squeegee 6 to reset. Then, the conveyor belt 2 sends the next set of lead frames to be squeegeed into the space below the template 4. The above operation is repeated to squeegee the lead frame, improving the efficiency of squeegee application.

[0041] The foregoing has provided a detailed description of one embodiment of the present invention, but this description is merely a preferred embodiment and should not be construed as limiting the scope of the invention. All equivalent variations and modifications made within the scope of the claims of this invention should still fall within the patent coverage of this invention.

Claims

1. A non-welding process lead frame adhesive scraping device, comprising an adhesive scraping box (1), characterized in that, The glue scraper box (1) is rotatably connected to a conveyor belt (2), and the glue scraper frame (3) is slidably connected to the inside of the glue scraper box (1). The bottom of the glue scraper frame (3) is detachably connected to a template (4). The scraper frame (3) has a slider (5) slidably connected inside. The bottom of the slider (5) is provided with a scraper (6) for scraping glue. A pressure cylinder (7) is fixedly connected to one side of the scraper frame (3). The pressure cylinder (7) is connected to the inside of the scraper frame (3) through a connecting pipe (701). A piston rod (702) is slidably connected inside the pressure cylinder (7). One end of the piston rod (702) passes through the pressure cylinder (7) and the scraper frame (3) and cooperates with the slider (5). A scraper motor (301) is fixedly connected to one side of the outer wall of the scraper frame (3). The output end of the scraper motor (301) passes through the scraper frame (3) and is fixedly connected to a lead screw (302). The lead screw (302) is rotatably connected inside the scraper frame (3). The slider (5) is threadedly connected to the outer wall of the lead screw (302), and both ends of the slider (5) are in contact with the inner walls on both sides of the scraper frame (3). The scraper (6) has an inclined surface on one side, and a glue storage cavity (601) is opened inside the scraper (6). Multiple sets of glue outlet holes (602) penetrating the scraper (6) are opened on one side of the glue storage cavity (601). A glue inlet pipe (603) is fixedly connected to one side of the glue storage cavity (601). The bottom of the slider (5) is slidably connected to a slide rod (501), and the scraper (6) is fixedly connected to the bottom of the slide rod (501). A pressure spring (502) is sleeved on the outer wall of the slide rod (501), and the two ends of the pressure spring (502) abut against the slider (5) and the scraper (6) respectively. The scraper (3) has a fixed block (13) inside, and a collection groove (131) is opened inside the fixed block (13). A triangular block (132) is fixedly connected to one side of the fixed block (13).

2. The lead frame adhesive scraping device for a non-welding process according to claim 1, characterized in that, The two ends of the conveyor belt (2) pass through both sides of the glue scraper box (1) and extend to the outside. Two sets of rotating shafts (201) are rotatably connected to both sides of the glue scraper box (1). The conveyor belt (2) is driven to the outer wall of the two sets of rotating shafts (201). A transmission motor (202) is fixedly connected to the outer wall of one side of the glue scraper box (1). The output end of the transmission motor (202) is connected to one set of the rotating shafts (201).

3. The lead frame adhesive scraping device according to claim 1, characterized in that, A lifting cylinder (12) is fixedly connected to the top of the glue scraper box (1). The output end of the lifting cylinder (12) passes through the glue scraper box (1) and is connected to the top of the glue scraper frame (3).

4. The lead frame adhesive scraping device according to claim 1, characterized in that, The glue scraper (3) has two sets of fixing plates (9) symmetrically arranged on both sides. The bottom of the fixing plate (9) is fixedly connected to a trapezoidal block (901) for correcting the lead frame.

5. The lead frame adhesive scraping device according to claim 1, characterized in that, The glue scraper box (1) is fixedly connected to a support plate (203). The top of the support plate (203) is flush with the top surface of the conveyor belt (2). The bottom inner wall of the glue scraper box (1) is fixedly connected to a positioning cylinder (10). The output end of the positioning cylinder (10) is fixedly connected to a positioning plate (11).

6. The lead frame adhesive scraping device for a non-welding process according to claim 5, characterized in that, The inner wall of the glue scraper box (1) is fixedly connected to two sets of baffles (101). The two sets of baffles (101) are located on both sides of the conveyor belt (2). The side wall of the baffle (101) is provided with a groove (1011). Multiple sets of guide wheels (1012) are rotatably connected inside the groove (1011).

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