A circuit board welding positioning fixture

Abstract

This utility model belongs to the field of welding fixture technology, specifically relating to a circuit board welding positioning fixture, comprising: a negative pressure positioning base, with multiple upper and lower mounting slots on the side for rotatably mounting an upper and lower adjusting shaft, each upper and lower mounting slot being connected to multiple negative pressure suction holes, which are equidistantly spaced along the axial direction of the upper and lower mounting slots; vent holes on the lower and upper adjusting shafts, each vent hole being connected to a negative pressure suction hole; and a lower housing, which covers the bottom of the negative pressure positioning base and is equipped with an exhaust fan. By combining and rotating the upper and lower adjusting shafts to appropriate positions, the air path of the negative pressure suction hole is precisely opened at a single point, enabling this fixture to achieve negative pressure positioning of flexible circuit boards of different shapes with low power consumption, effectively reducing processing costs.

Description

Technical Field

[0001] This utility model belongs to the field of welding tooling technology, specifically relating to a circuit board welding positioning tooling. Background Technology

[0002] In the welding process of flexible circuit boards, the accuracy and stability of positioning directly affect the welding quality and production efficiency. Due to the softness of the material and the variety of shapes (such as irregular notches, multi-branch structures, etc.), traditional mechanical clamping positioning methods are prone to board deformation and edge damage, and are difficult to adapt to the rapid switching of different shaped circuit boards. Therefore, they have been gradually replaced by negative pressure adsorption positioning fixtures.

[0003] Existing negative pressure positioning fixtures typically employ a design approach of full-area negative pressure adsorption. This involves creating dense negative pressure suction holes on the positioning base and using an air extraction device to form a negative pressure zone across the entire base surface, thereby adsorbing and fixing the flexible circuit board. However, this design has significant drawbacks in practical applications:

[0004] First, the energy consumption and cost are too high. To ensure full coverage of circuit boards of different shapes, the negative pressure suction holes are often fully open. Even for small or irregularly shaped circuit boards, many areas that do not need to be suctioned remain under negative pressure, forcing the suction device to maintain high power operation continuously, resulting in energy waste. At the same time, the full-area negative pressure design places high demands on the power of the suction device, significantly increasing equipment procurement and operating costs. Especially in mass production, long-term high energy consumption will significantly increase the company's production costs.

[0005] Secondly, the positioning accuracy is insufficient. During full-area negative pressure adsorption, the negative pressure suction holes not covered by the circuit board will continuously draw in external air, causing the negative pressure value of the effective adsorption area to be unstable, which can easily lead to insufficient local adsorption force. For flexible circuit boards, this negative pressure fluctuation may cause micro-movement of the board, especially in precision welding processes (such as chip pin welding). Even a small displacement can cause quality problems such as poor soldering and mis-soldering, reducing the product qualification rate.

[0006] Furthermore, it suffers from poor adaptability. The required locations of the negative pressure suction holes vary significantly depending on the shape of the flexible circuit board. Existing fixtures, to achieve targeted suction, require a complex solenoid valve control system to individually open and close each suction hole. This not only results in a complex structure and a high failure rate, but also lengthy debugging times when switching between different circuit board models, severely impacting production efficiency. In addition, the addition of solenoid valves and other electronically controlled components increases the difficulty and cost of fixture maintenance. In high-temperature, dusty welding environments, component aging can easily lead to negative pressure control failure. Utility Model Content

[0007] To address the above problems, the purpose of this utility model is to provide a circuit board welding positioning fixture that solves the problems of high energy consumption and cost, and insufficient positioning accuracy of existing negative pressure positioning fixtures due to their full-area negative pressure adsorption design.

[0008] To achieve the above objectives, the present invention adopts the following technical solution: a circuit board welding positioning fixture, comprising:

[0009] A negative pressure positioning base has multiple upper and lower mounting slots horizontally extending through its side. These upper and lower mounting slots are spaced vertically apart. Each upper and lower mounting slot is connected to multiple negative pressure suction holes, which are vertically extending through the negative pressure positioning base and equidistantly spaced along the axial direction of the upper and lower mounting slots.

[0010] The upper adjusting shaft is rotatably mounted in the upper mounting groove.

[0011] The lower adjusting shaft and the upper adjusting shaft both include a main shaft. The main shaft is rotatably mounted in the upper mounting groove and the lower mounting groove. Multiple vent holes are provided along the radial direction of the main shaft, and each vent hole is adapted to connect to a negative pressure suction hole.

[0012] The lower housing is fitted onto the bottom of the negative pressure positioning base. An exhaust fan is installed on the lower housing, and a slot is provided that is opposite to the air duct of the exhaust fan.

[0013] The beneficial effects of this utility model are as follows: by combining the upper and lower adjustment shafts at appropriate positions, the air passage of the negative pressure suction hole can be precisely opened at a single point, enabling this tooling to achieve negative pressure positioning of flexible circuit boards of different shapes with low power consumption, effectively reducing processing costs.

[0014] To ensure the airtightness of the cavity formed between each vent hole and the negative pressure suction hole;

[0015] As a further improvement to the above technical solution: annular grooves for fitting O-rings are provided on the outer sides of the main shafts on both sides of the vent hole, and the O-rings are interference-fitted with the upper mounting groove and the lower mounting groove.

[0016] The beneficial effects of this improvement are: the O-rings act as a seal, effectively isolating the cavity formed between each vent hole and the negative pressure suction hole.

[0017] To ensure the stability of the spindle when mounted on the negative pressure positioning base;

[0018] As a further improvement to the above technical solution: the main shaft has an annular groove for fitting a C-shaped retaining spring at one end located outside the negative pressure positioning base, and one side of the C-shaped retaining spring slides against the side of the negative pressure positioning base. The other end of the main shaft is connected to a knob, which slides against the other side of the negative pressure positioning base.

[0019] The beneficial effects of this improvement are: the knob and C-shaped retaining ring act as limiters, effectively ensuring the axial stability of the spindle.

[0020] To facilitate personnel to rotate and position the ventilation holes at an angle to accurately block or connect the negative pressure suction holes;

[0021] As a further improvement to the above technical solution: a positioning groove is provided on the side of the knob facing the negative pressure positioning base. The positioning groove has a fan-shaped annular groove structure. A limiting block is formed protruding from the side of the negative pressure positioning base. A limiting block is provided around the hole end of each upper mounting groove and lower mounting groove. The limiting block is located inside the positioning groove.

[0022] The beneficial effect of this improvement is that when the vent hole is rotated to the point where its axis is collinear with or perpendicular to the axis of the negative pressure suction hole, the limiting block connects with the two inner end faces of the positioning groove, thereby achieving rapid positioning of the vent hole angle.

[0023] In order to effectively improve the safety of tooling use;

[0024] As a further improvement to the above technical solution: a safety valve is installed on the lower housing.

[0025] The beneficial effect of this improvement is that when the number of negative pressure suction holes that can be connected to the lower housing is small, resulting in excessively low negative pressure inside the lower housing, the safety valve opens to prevent insufficient air intake from affecting the normal operation of the exhaust fan.

[0026] This tooling is used to provide stable support.

[0027] As a further improvement to the above technical solution: supports are installed on both sides of the bottom of the lower housing.

[0028] The beneficial effects of this improvement are: the support can be used to support the lower housing, so that the exhaust fan and the tooling support surface are kept at a certain distance, thereby allowing the air in the lower housing to be smoothly delivered to the outside by the exhaust fan.

[0029] The parts of the device not covered herein are the same as or can be implemented using existing technologies. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the structure of the present invention. Figure 1 ;

[0031] Figure 2 This is a schematic diagram of the structure of the present invention. Figure 2 ;

[0032] Figure 3 This is a cross-sectional view of the negative pressure positioning base in this utility model;

[0033] Figure 4 This is a schematic diagram of the upper adjusting shaft in this utility model;

[0034] Figure 5 This is an enlarged view of A in this utility model;

[0035] In the diagram: 1. Negative pressure positioning base; 11. Upper mounting slot; 12. Lower mounting slot; 13. Limiting block; 2. Negative pressure suction hole; 3. Upper adjusting shaft; 31. Main shaft; 32. Vent hole; 33. O-ring; 34. C-type retaining ring; 35. Knob; 36. Positioning slot; 4. Lower adjusting shaft; 5. Lower housing; 6. Exhaust fan; 7. Safety valve; 8. Support. Detailed Implementation

[0036] To enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be described in detail below with reference to the accompanying drawings. The description in this part is only exemplary and explanatory, and should not be used to limit the scope of protection of the present invention in any way.

[0037] Example 1:

[0038] like Figure 1 As shown in Figure 5: A circuit board welding positioning fixture, comprising:

[0039] A negative pressure positioning base 1 has multiple upper mounting slots 11 and lower mounting slots 12 horizontally extending through its side. The upper mounting slots 11 and lower mounting slots 12 are spaced vertically apart. Each upper mounting slot 11 and lower mounting slot 12 is connected to multiple negative pressure suction holes 2. The negative pressure suction holes 2 are vertically extending through the negative pressure positioning base 1 and are equidistantly spaced along the axial direction of the upper mounting slots 11 and lower mounting slots 12.

[0040] Upper adjusting shaft 3 is rotatably mounted in upper mounting groove 11.

[0041] The lower adjusting shaft 4 and the upper adjusting shaft 3 both include a main shaft 31. The main shaft 31 is rotatably mounted in the upper mounting groove 11 and the lower mounting groove 12. Multiple vent holes 32 are provided through the main shaft 31 along the radial direction of the main shaft 31. Each vent hole 32 is adapted to connect to a negative pressure suction hole 2.

[0042] The lower housing 5 is fitted onto the bottom of the negative pressure positioning base 1. An exhaust fan 6 is mounted on the lower housing 5, and a slot is provided corresponding to the air duct of the exhaust fan 6. By combining and rotating the upper adjusting shaft 3 and the lower adjusting shaft 4 to appropriate positions, the air passage of the negative pressure suction hole 2 can be precisely opened at a single point. This allows the fixture to achieve negative pressure positioning of flexible circuit boards of different shapes with low power consumption, effectively reducing processing costs. The outer sides of the main shaft 31 on both sides of the vent 32 are provided with annular grooves for fitting O-rings 33. The upper mounting groove 11 and lower mounting groove 12 are interference fits, and the O-ring 33 acts as a seal, effectively isolating the cavity formed between each vent hole 32 and the negative pressure suction hole 2. The main shaft 31 has an annular groove at one end located outside the negative pressure positioning base 1 for fitting a C-type retaining spring 34, and one side of the C-type retaining spring 34 slides against the side of the negative pressure positioning base 1. The other end of the main shaft 31 is connected to a knob 35, which slides against the other side of the negative pressure positioning base 1. The knob 35 and the C-type retaining spring 34 act as a limit... The knob 35 has a positioning groove 36 on the side facing the negative pressure positioning base 1. The positioning groove 36 has a fan-shaped annular groove structure. The side of the negative pressure positioning base 1 has a protruding limiting block 13. Each upper mounting groove 11 and lower mounting groove 12 has a limiting block 13 around its hole end. The limiting block 13 is located inside the positioning groove 36. When the vent hole 32 is rotated to the point where its axis is collinear with or perpendicular to the axis of the negative pressure suction hole 2, the limiting block 13 is respectively positioned in the positioning groove 36. The two inner end faces meet to achieve rapid positioning of the vent hole 32 angle. A safety valve 7 is installed on the lower housing 5. When the number of negative pressure suction holes 2 that can connect to the lower housing 5 is small, resulting in the negative pressure inside the lower housing 5 being too low, the safety valve 7 opens to prevent insufficient air intake from affecting the normal operation of the exhaust fan 6. Supports 8 are installed on both sides of the bottom of the lower housing 5. The supports 8 can be used to support the lower housing 5, so that the exhaust fan 6 and the tooling support surface are kept at a certain distance, so that the air inside the lower housing 5 can be smoothly sent to the outside by the exhaust fan 6.

[0043] The working principle of this technical solution is as follows: Based on the shape of the flexible circuit board to be welded, determine the position of the negative pressure suction hole 2 that needs to be opened: Rotate the knob 35 of the upper adjustment shaft 3 in the corresponding mounting groove 11 to align the vent hole 32 on the main shaft 31 with the target negative pressure suction hole 2. When the limiting block 13 contacts the inner end face of one side of the positioning groove 36, the axis of the vent hole 32 is collinear with the axis of the negative pressure suction hole 2, and the air path is open. For the negative pressure suction holes 2 that do not need to be opened, rotate the knob 35 in the opposite direction until the limiting block 13 contacts the inner end face of the other side of the positioning groove 36. At this time, the axis of the vent hole 32 is perpendicular to the axis of the negative pressure suction hole 2, and the air path is closed. Adjust the lower adjustment shaft 4 in the same way to ensure that all areas that need to be adsorbed have corresponding negative pressure suction holes 2 in the open state, and all irrelevant suction holes are closed to reduce ineffective air extraction.

[0044] The flexible circuit board is laid flat on the upper surface of the negative pressure positioning base 1, so that the area of ​​the circuit board to be adsorbed corresponds to the position of the open negative pressure suction hole 2. The exhaust fan 6 is turned on, and the exhaust fan 6 draws in the internal air through the slot of the lower housing 5, so that the lower housing 5, the open negative pressure suction hole 2, and the ventilation hole 32 form a closed negative pressure cavity. Under the action of air pressure difference, the flexible circuit board is firmly adsorbed on the surface of the base. At this time, the adsorption effect can be judged by observing whether the circuit board is flat.

[0045] During the welding process, if the negative pressure is too low due to too few suction holes, the safety valve 7 will automatically open to replenish air, preventing the exhaust fan 6 from being damaged due to excessive load. If the circuit board position needs to be temporarily adjusted, the exhaust fan 6 can be turned off. After the negative pressure disappears, the circuit board can be moved and the exhaust fan 6 can be restarted.

[0046] When switching between flexible circuit boards of different shapes, there is no need to disassemble the tooling. Simply readjust the position of the vent 32 of the upper adjustment shaft 3 and the lower adjustment shaft 4 by turning knob 35, and repeat the above steps to complete the quick changeover, which greatly shortens the debugging time.

[0047] It should be noted that, in this document, the terms “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0048] This article uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only for the purpose of helping to understand the method and core ideas of the present invention. The above descriptions are only preferred embodiments of the present invention. It should be noted that due to the limitations of textual expression, there are objectively infinite specific structures. For those skilled in the art, several improvements, modifications, or changes can be made without departing from the principles of the present invention, and the above technical features can also be combined in an appropriate manner. These improvements, modifications, changes, or combinations, or the direct application of the inventive concept and technical solution to other situations without modification, should all be considered within the scope of protection of the present invention.

Claims

1. A circuit board welding positioning fixture, characterized in that: include: A negative pressure positioning base (1) has multiple upper mounting slots (11) and lower mounting slots (12) horizontally extending through its side. The upper mounting slots (11) and lower mounting slots (12) are spaced vertically apart. Both the upper mounting slots (11) and lower mounting slots (12) are connected to multiple negative pressure suction holes (2). The negative pressure suction holes (2) are vertically extending through the negative pressure positioning base (1) and are equidistantly spaced along the axial direction of the upper mounting slots (11) and lower mounting slots (12). The upper adjusting shaft (3) is rotatably mounted in the upper mounting groove (11). The lower adjusting shaft (4) and the upper adjusting shaft (3) both include a main shaft (31). The main shaft (31) is rotatably mounted in the upper mounting groove (11) and the lower mounting groove (12). Multiple vent holes (32) are provided on the main shaft (31) along the radial direction of the main shaft (31). Each vent hole (32) is adapted to connect to a negative pressure suction hole (2). The lower housing (5) is fitted over the bottom of the negative pressure positioning base (1). An exhaust fan (6) is installed on the lower housing (5) and a slot is provided that is opposite to the air duct of the exhaust fan (6).

2. The circuit board welding positioning fixture according to claim 1, characterized in that: The outer side of the main shaft (31) on both sides of the vent (32) is provided with an annular groove adapted to fit the O-ring (33), and the O-ring (33) is interference-fitted with the upper mounting groove (11) and the lower mounting groove (12).

3. The circuit board welding positioning fixture according to claim 1, characterized in that: The main shaft (31) has an annular groove for fitting a C-type retaining spring (34) at one end outside the negative pressure positioning base (1), and one side of the C-type retaining spring (34) slides against the side of the negative pressure positioning base (1). The other end of the main shaft (31) is connected to a knob (35), which slides against the other side of the negative pressure positioning base (1).

4. The circuit board welding positioning fixture according to claim 3, characterized in that: The knob (35) has a positioning groove (36) on the side facing the negative pressure positioning base (1). The positioning groove (36) has a fan-shaped annular groove structure. The side of the negative pressure positioning base (1) has a protruding limiting block (13). A limiting block (13) is provided around the hole end of each upper mounting groove (11) and lower mounting groove (12). The limiting block (13) is located inside the positioning groove (36).

5. The circuit board welding positioning fixture according to claim 1, characterized in that: A safety valve (7) is installed on the lower housing (5).

6. The circuit board welding positioning fixture according to claim 1, characterized in that: Supports (8) are installed on both sides of the bottom of the lower housing (5).

Images