Curved surface self-adaptive soldering flux printing method and printing device

Abstract

The invention relates to a curved surface self-adaptive soldering flux printing method, which comprises the following steps of: 1, arranging a guide needle in a through hole of a printing plate, and pushing the guide needle for the first time through air pressure; 2, the guide needle moves along the through hole and extends out of the through hole to reach the dipping position, air pressure pushing is stopped, and the guide needle dips the soldering flux; 3, pushing the guide pin for the second time through air pressure, and stopping pushing the guide pin after the guide pin touches the substrate; and 4, the printing plate is moved to the top plate and pressed downwards, the guide needle is reset upwards to the dipping position so as to dip the scaling powder again, and printing operation is circulated. A curved surface self-adaptive soldering flux printing device comprises a printing plate, a guide needle and a guide needle contraction transmission piece. The coating device has the advantages that an efficient coating solution suitable for the large-warping substrate is provided, the coating quality of the scaling powder is effectively improved, the problem of uneven coating or waste caused by warping of the substrate is solved through the telescopic design of the printing salient points, and the coating device can be suitable for scaling powder printing of various curved surfaces.

Description

Technical Field

[0001] This invention relates to the field of semiconductor packaging technology, and in particular to a method and apparatus for printing flux on curved surfaces in an adaptive manner. Background Technology

[0002] In electronics manufacturing, when applying flux to large or uneven substrates, traditional planar stencils sometimes fail to effectively adapt to the curved shape of the substrate, resulting in uneven coating or unsatisfactory results. Existing technologies for improving substrate flux coating processes do not consider the practical problems of substrates with large warpages, and mostly focus on solving accuracy and efficiency issues.

[0003] Therefore, further improvements are needed to the flux coating process and equipment for irregularly shaped substrates to address the quality issue of uneven flux coating. Summary of the Invention

[0004] The purpose of this invention is to provide a curved surface adaptive flux printing method and printing apparatus, which can adapt to substrate surfaces with different warpages by using controllable bumps on a stencil, thereby achieving high-quality flux coating.

[0005] A first aspect of the present invention provides a method for adaptive flux printing on curved surfaces, comprising the following steps:

[0006] Step 1: Insert a pin into the through hole of the printed circuit board and push the pin for the first time using air pressure;

[0007] Step 2: Move the pin along the through hole. After the bottom of the pin extends out of the through hole and reaches the dipping position, stop the air pressure push and dip the bottom of the pin into the flux.

[0008] Step 3: Push the pin a second time using air pressure. The pin continues to move downwards. Stop pushing the pin after the bottom of the pin touches the substrate.

[0009] Step 4: After completing the printing of a single substrate, move the printed circuit board to the top plate and press it down. Reset the pins upward to the dip position to dip them in flux again and perform a cycle of printing.

[0010] In steps 1-4 above, the extension and retraction of the probe are monitored using an optical detection system.

[0011] In steps 1-4 above, the printing plate is spaced out with pins to perform step-by-step printing.

[0012] In step 1 above, the bottom of the printed circuit board is masked according to the distribution of the solder pads on the substrate to shield excess holes.

[0013] Based on the above-mentioned surface adaptive flux printing method, a second aspect of the present invention provides a surface adaptive flux printing apparatus for operating the above-mentioned surface adaptive flux printing method, specifically including a printing plate, a pin, and a pin retraction transmission component.

[0014] The printed circuit board has several through holes, the pin is located in the through holes, and the head of the pin is provided with a slider; the pin retraction transmission component is located above the printed circuit board.

[0015] The printing plate has a top plate on one side;

[0016] The printed circuit board is used for setting the pins in step 1;

[0017] The lead pin is used for dipping and coating flux in steps 2-4;

[0018] The needle retraction transmission component is used for the extension of the needle in steps 1-3;

[0019] The top plate is used for pin reset in step 4.

[0020] Preferably, the bottom of the through hole is provided with a stop block, the stop block is provided with a limiting hole, and the guide pin is coaxially arranged with the limiting hole.

[0021] As a further improvement to the invention, the needle retraction transmission component is provided with an optical detection mechanism.

[0022] As a further improvement to the invention, the various through holes are spaced apart on the printed circuit board.

[0023] As a further improvement to the invention, a mask is provided at the locations of the excess through holes.

[0024] The key point of this invention is a printing bump telescopic scheme for flux coating in electronic manufacturing, replacing traditional stencil coating. It involves setting up pins adapted to the substrate. First, air pressure generated by a pin retraction drive pushes the pin downward for the first time. When the pin slightly protrudes from the through-hole, the pin retraction drive stops operating. Using existing mobile equipment, the printed circuit board and the pin retraction drive are moved together to the flux tank for flux dipping. Then, the flux-dipped pin is moved above the substrate, and air pressure generated by the pin retraction drive pushes the pin downward for the second time. When the pin touches the solder pad, the pin retraction drive stops operating. The duration of the pin touching the solder pad can be set according to the size of the solder pad and coating requirements. During the contact time, flux is applied to the solder pad. After the duration is reached, the pin retraction drive stops working, completing the flux printing operation for a single batch of substrates. The pin then returns to the dipping position, and the flux dipping and printing are repeated cyclically to achieve mass production.

[0025] The advantages of the curved surface adaptive flux printing method and printing apparatus of the present invention compared with the prior art are as follows:

[0026] This invention provides an efficient coating solution for substrates with large warpage, which effectively improves flux coating quality. By utilizing the telescoping design of the printed bumps, it reduces the problem of uneven coating or waste caused by substrate warpage and can be applied to flux printing on various curved surfaces. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of a curved surface adaptive flux printing method according to the present invention;

[0028] Figure 2 This is a schematic diagram of the connection of a curved surface adaptive flux printing device according to the present invention;

[0029] Figure 3 This is a schematic diagram of the needle structure;

[0030] Figure 4 A schematic diagram of flux coating on the pilot pin;

[0031] Figure 5 This is a schematic diagram of a printed circuit board mask.

[0032] Figure 6 Diagram showing pin reset. Detailed Implementation

[0033] The specific embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

[0034] like Figure 1 As shown, in a first aspect, the present invention provides a method for printing adaptive flux on curved surfaces, comprising the following steps:

[0035] Step 1: Insert a pin into the through hole of the printed circuit board and push the pin for the first time using air pressure;

[0036] Step 2: Move the pin along the through hole. After the bottom of the pin extends out of the through hole and reaches the dipping position, stop the air pressure push and dip the bottom of the pin into the flux.

[0037] Step 3: Push the pin a second time using air pressure. The pin continues to move downwards. Stop pushing the pin after the bottom of the pin touches the substrate.

[0038] Step 4: After completing the printing of a single substrate, move the printed circuit board to the top plate and press it down. Reset the pins upward to the dip position to dip them in flux again and perform a cycle of printing.

[0039] In steps 1-4 above, the extension of the probe is monitored using an optical detection system.

[0040] In steps 1-4 above, the printing plate is spaced out with pins to perform step-by-step printing.

[0041] In step 1 above, the bottom of the printed circuit board is masked according to the distribution of the solder pads on the substrate to shield excess holes.

[0042] like Figure 2-4 As shown, based on the above-mentioned surface adaptive flux printing method, a second aspect of the present invention provides a surface adaptive flux printing apparatus, which operates the above-mentioned surface adaptive flux printing method, specifically including a printing plate 1, a pin 2, and a pin retraction transmission component 3.

[0043] The printing plate 1 has several through holes 11, the pin 2 is located in the through holes 11, and the head of the pin 2 is provided with a slider 21; the pin retraction transmission component 3 is located above the printing plate 1.

[0044] A top plate 5 is provided on one side of the printing plate 1.

[0045] Printed plate 1, used for setting the pins in step 1;

[0046] Pin 2 is used for dipping and coating flux in steps 2-4;

[0047] The needle retraction transmission component 3 is used for the extension of the needle in steps 1-3;

[0048] Top plate 5 is used for resetting the pin in step 4.

[0049] The pin retraction drive 3 can be an existing air pump, which provides air pressure to move the pins 2 in each through hole 11, and the slider 21 moves up and down along the through hole 11. The air pressure value can be adjusted by the air pump according to the warping of the substrate 4, thereby adjusting the extension stroke of the pins 2.

[0050] A stop 12 is provided at the bottom of the through hole 11. The stop 12 has a limiting hole 13. The pin 2 is coaxially arranged with the limiting hole 13. The pin 2 passes through the limiting hole 13, while the slider 21 is blocked by the stop 12, which limits the maximum distance that the pin 2 can move downward, and prevents the pin 2 from falling too far, causing the pin tip to collide with the solder pad 41 of the substrate 4.

[0051] Due to the unique nature of the semiconductor packaging industry, the flux printing area is extremely small and difficult to observe with the naked eye. The pin retraction transmission component 3 is equipped with an optical inspection mechanism 31, which can be an existing camera device. This mechanism uploads a three-dimensional image of the pin 2 after it extends out of the printed circuit board 1 to a terminal display, facilitating administrator observation and ensuring that the bottoms of each pin 2 remain on the same plane, thereby improving printing accuracy.

[0052] After the flux is printed on the first substrate 4, the printed circuit board 1 can be moved to the top plate 5 using existing mobile equipment, and the printed circuit board 1 can be pressed down, such as... Figure 6 As shown, the slider 21 is interference-fitted with the through hole 11. When the printed circuit board 1 is pressed down, the extended pin 2 abuts against the top plate 5 and moves upward along the through hole 11 to reset the pin 2 to the flux dipping position. The top plate 5 can be set near the flux dipping tank. After the pin 2 is reset by the top plate 5, it immediately dips in flux and proceeds to the printing of the next substrate.

[0053] The number and position of each pin 2 on the printed circuit board 1 are matched with the number of solder pads 41 on the target substrate 4. After dipping in flux, synchronous printing of the substrate 4 can be achieved. When the spacing between the solder pads 41 on the substrate 4 is too small, synchronous printing is difficult and may even affect the flux coating quality. Relative to the position of the solder pads 41, the through holes 11 are spaced apart on the printed circuit board 1 for step-by-step printing to ensure the printing quality of the substrate 4 with dense solder pads 41.

[0054] like Figure 5 As shown, when the solder pads 41 on the substrate are asymmetrically distributed, a mask 5 can be set at the position of the extra through holes 11 on the printed circuit board 1 to shield the extra holes.

[0055] This invention relates to a curved surface adaptive flux printing apparatus, which provides a printing bump extension and retraction scheme for flux coating in electronic manufacturing, replacing traditional stencil coating. It features pins adapted to the substrate. First, air pressure generated by the pin retraction drive 3 pushes the pin 2 downward for the first time. When the pin 2 slightly protrudes from the through-hole 11, the pin retraction drive 3 stops operating. Using existing mobile equipment, the printing plate 1 and the pin retraction drive 3 are moved as a whole to the flux tank for flux dipping. Then, the flux-dipping pin 2 is moved to the substrate. Above 4, the air pressure generated by the pin retraction drive 3 pushes the pin 2 to move downward for the second time. When the pin 2 touches the solder pad 41, the pin retraction drive 3 stops operating. The duration of the pin 2 touching the solder pad 41 can be set according to the size of the solder pad 41 and the coating requirements. During the contact time, flux is applied to the solder pad 41. After the duration is reached, the pin retraction drive 3 stops working, completing the flux printing operation of a single batch of substrates. Then the pin 2 returns to the dip position, and the flux dipping and printing are repeated to achieve mass production.

[0056] The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited to the embodiments described. Those skilled in the art can make various equivalent modifications or substitutions without departing from the spirit of the present invention, and these equivalent modifications or substitutions are all included within the scope defined by the claims of this application.

Claims

1. A curved surface adaptive solder flux printing method, characterized in that: The steps include: Step 1: A lead pin is set in the through hole of the printed board, and the lead pin is pushed for the first time by air pressure; Step 2: The lead pin moves along the through hole, and after the bottom of the lead pin extends out of the through hole, it reaches the dipping position, and the air pressure push is stopped, and the bottom of the lead pin dips into the flux; Step 3: The guide needle is pushed for the second time by air pressure, and the guide needle continues to move downward. After the bottom of the guide needle touches the substrate, the pushing of the guide needle stops; Step 4: After completing the printing of a single substrate, move the printing plate to the top plate and press it down, and reset the lead pin upward to the dipping position to dip the flux again for a cyclic printing operation.

2. A curved surface adaptive solder flux printing method as claimed in claim 1, characterized in that: The extension and retraction of the guide needle is monitored through an optical detection system.

3. A curved surface adaptive solder flux printing method as claimed in claim 1, characterized in that: The printing plate is provided with lead pins at intervals for step-by-step printing.

4. A curved surface adaptive solder flux printing method as claimed in claim 1, characterized in that: The bottom of the printed circuit board is masked according to the distribution of the solder pads on the substrate to shield the redundant holes.

5. A curved surface adaptive solder flux printing device, characterized in that: Running the above-mentioned curved surface adaptive solder flux printing method, specifically including a printing plate, a lead pin, and a lead pin retracting transmission member; The printing plate is provided with a plurality of through holes, the lead pins are located in the through holes, and the heads of the lead pins are provided with sliders; the lead pin retracting transmission member is located above the printing plate; A top plate is provided on one side of the printing plate; The printed board is used for setting the lead pins in step 1; The lead pin is used for dipping and coating the soldering flux in steps 2-4; The needle introduction retraction transmission member is used for extending the needle introduction in steps 1-3; The top plate is used for resetting the lead pin in step 4.

6. A curved surface adaptive solder flux printing device as claimed in claim 5, characterized in that: A stopper is provided at the bottom of the through hole, the stopper is provided with a limiting hole, and the guide pin is coaxially arranged with the limiting hole.

7. A curved surface adaptive solder flux printing device as claimed in claim 5, characterized in that: The needle-introducing retracting transmission member is provided with an optical detection mechanism.

8. The curved surface adaptive solder flux printing device according to claim 5, characterized in that: The through holes are arranged on the printed board at intervals.

9. The curved surface adaptive solder flux printing device according to claim 5, characterized in that: Masks are set at the redundant through-hole positions.

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