A welding head mechanism for a chip placement machine

Abstract

The present invention discloses a welding head mechanism for a chip placement machine, comprising a welding head unit and a visual unit, wherein the welding head unit comprises a mounting base, a rotating assembly and a suction nozzle, the rotating assembly being a hollow structure, and the visual unit being located above the welding head unit and arranged facing the hollow portion of the rotating assembly. The rotating assembly can drive the suction nozzle to rotate, and at the same time, the rotating assembly can reciprocate relative to the mounting base in a direction parallel to the axis of rotation, so that the suction nozzle can adjust its position in space. The present invention utilizes the cooperation between the rotating assembly and the mounting base to improve the movement accuracy of the welding head unit and ensure the smooth progress of chip placement; in addition, the rotating assembly is a hollow structure, the working end of the suction nozzle is located below the hollow portion of the rotating assembly, and the visual unit is located above the hollow portion of the rotating assembly, so that the visual assembly can face the suction nozzle and the chip to obtain an image, thereby improving the visual compensation accuracy, and combining the welding head unit to drive the suction nozzle to move accurately, thereby improving the chip placement accuracy.

Description

Technical Field

[0001] The present invention relates to the technical field of integrated circuit packaging equipment and peripheral supporting facilities thereof, in particular to a chip placement machine welding head mechanism. Background Art

[0002] High-precision chip mounters are essential equipment in the integrated circuit packaging process, primarily used to complete the chip placement step in the packaging process. Chip placement is the process of assembling the chip onto the lead frame.

[0003] The bond head mechanism is the most critical component of a chip placement machine, removing the chip from the wafer and attaching it to the lead frame. The bond head must possess vacuum suction capabilities, the ability to rotate an angle, precisely control the force applied to the chip, and be able to compensate for chip placement deviations using vision components.

[0004] Most existing visual compensation methods for welding head structures use photographic compensation, and the image is obtained from one side of the welding head. The obtained image has deviations that affect the compensation effect. At the same time, it is constrained by the lack of overall structural motion accuracy, which further reduces the patch accuracy.

[0005] Therefore, how to change the current situation in the existing technology where the visual component compensation effect of the placement machine is poor and the movement accuracy of the welding head structure is insufficient, which reduces the placement accuracy, has become an urgent problem to be solved by technical personnel in this field. Summary of the Invention

[0006] The purpose of the present invention is to provide a chip placement machine welding head mechanism to solve the problems existing in the above-mentioned prior art and improve the chip placement accuracy of the chip placement machine.

[0007] To achieve the above-mentioned object, the present invention provides the following solution: The present invention provides a placement machine welding head mechanism, comprising:

[0008] The welding head unit includes a mounting base, a rotating assembly and a suction nozzle, the rotating assembly is slidably arranged on the mounting base, the suction nozzle is arranged on the rotating assembly, the rotating assembly can drive the suction nozzle to rotate, the rotating assembly is a hollow structure, and the rotation axis of the rotating assembly is located in the hollow of the rotating assembly, and the rotation axis of the rotating assembly is parallel to the reciprocating sliding direction of the rotating assembly; the suction nozzle has a working end, and in a plane perpendicular to the rotation axis of the rotating assembly, the projection of the working end is located in the projection area of ​​the hollow of the rotating assembly; the working end can pick up the chip;

[0009] A visual unit is located above the welding head unit and is arranged facing the hollow part of the rotating component. The visual unit can acquire images.

[0010] Preferably, the rotating assembly includes a mounting disk, a bearing seat and a driver, the mounting disk is rotatably disposed on the bearing seat, the bearing seat is slidably disposed on the mounting seat, the suction nozzle is disposed on the mounting disk, the driver is fixed on the bearing seat, the driver is transmission-connected to the mounting disk, and the bearing seat and the mounting disk are both hollow structures.

[0011] Preferably, the suction nozzle is an inclined structure, one end of the suction nozzle is connected to the mounting plate, and the other end of the suction nozzle extends to the rotation axis of the mounting plate.

[0012] Preferably, a disc bearing is provided between the mounting plate and the bearing seat.

[0013] Preferably, the rotating assembly further includes a bushing, the output end of the driver is transmission-connected to the bushing, the bushing is connected to the mounting plate, and the bushing is a hollow structure.

[0014] Preferably, the rotating assembly further includes a driving wheel and a driven wheel, the driver is connected to the driving wheel, the driving wheel drives the driven wheel to rotate using a transmission belt, the driven wheel is connected to the bushing, and the driven wheel is a hollow structure.

[0015] Preferably, the rotation axis of the rotating assembly coincides with the axis of the hollow structure of the rotating assembly.

[0016] Preferably, the soldering head mechanism of the chip placement machine further includes an air circuit component, and the suction nozzle is connected to an external air source via the air circuit component, and the suction nozzle can adsorb the chip.

[0017] Preferably, the air circuit assembly includes a low-friction cylinder, the suction nozzle is connected to the external air source via the low-friction cylinder, and a control valve is provided between the low-friction cylinder and the external air source.

[0018] Preferably, an air bearing is provided between the rotating assembly and the mounting seat, the air bearing is connected to the external air source, and an elastic member is further provided between the rotating assembly and the mounting seat.

[0019] Compared with the prior art, the present invention has achieved the following technical effects:

[0020] The welding head mechanism of the chip placement machine of the present invention comprises a welding head unit including a rotating assembly, which can drive the suction nozzle to rotate, thereby adjusting the position of the suction nozzle in a plane perpendicular to the rotation axis of the rotating assembly. At the same time, the rotating assembly can reciprocate relative to the mounting seat in a direction parallel to the rotation axis, so that the suction nozzle can adjust its position in space, and the suction nozzle can pick up the chip, thereby realizing the movement of the chip. The present invention utilizes the cooperation between the rotating assembly and the mounting seat to improve the movement accuracy of the welding head unit and ensure the smooth progress of the chip placement; at the same time, the rotating assembly of the present invention is a hollow structure, the working end of the suction nozzle is located below the hollow part of the rotating assembly, and the visual unit is located above the hollow part of the rotating assembly, so that the visual assembly can acquire images facing the suction nozzle and the chip, thereby improving the visual compensation accuracy, and combining with the welding head unit to drive the suction nozzle to move precisely, thereby improving the chip placement accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0022] Figure 1 This is a schematic diagram of the disassembled structure of the soldering head mechanism of the placement machine disclosed in an embodiment of the present invention;

[0023] Figure 2 This is a front view of the soldering head mechanism of the chip placement machine disclosed in an embodiment of the present invention;

[0024] Figure 3 A top view of the soldering head mechanism of a chip placement machine disclosed in an embodiment of the present invention;

[0025] Figure 4 This is a schematic diagram of the control valve of the patch welding head mechanism disclosed in an embodiment of the present invention.

[0026] Among them, 1 is the mounting seat, 2 is the rotating assembly, 3 is the suction nozzle, 4 is the mounting plate, 5 is the bearing seat, 6 is the driver, 7 is the disc bearing, 8 is the bushing, 9 is the driving wheel, 10 is the driven wheel, 11 is the low-friction cylinder, 12 is the external air source, 13 is the first electrical proportional valve, 14 is the first solenoid valve, 15 is the second electrical proportional valve, 16 is the second solenoid valve, 17 is the third electrical proportional valve, 18 is the third solenoid valve, 19 is the pressure sensor, 20 is the air bearing, 21 is the elastic part, 22 is the vacuum joint, 23 is the adapter joint, and 24 is the adjustment mounting plate. DETAILED DESCRIPTION

[0027] The following will clearly and completely describe 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 the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0028] The purpose of the present invention is to provide a chip placement machine welding head mechanism to solve the problems existing in the above-mentioned prior art and improve the chip placement accuracy of the chip placement machine.

[0029] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0030] The present invention provides a welding head mechanism of a placement machine, comprising a welding head unit and a visual unit (not shown in the figure), wherein the welding head unit comprises a mounting base 1, a rotating component 2 and a suction nozzle 3, the rotating component 2 is slidably arranged on the mounting base 1, the suction nozzle 3 is arranged on the rotating component 2, the rotating component 2 can drive the suction nozzle 3 to rotate, the rotating component 2 is a hollow structure, and the rotation axis of the rotating component 2 is located in the hollow of the rotating component 2, and the rotation axis of the rotating component 2 is parallel to the reciprocating sliding direction of the rotating component; the suction nozzle 3 has a working end, and in a plane perpendicular to the rotation axis of the rotating component 2, the projection of the working end of the suction nozzle 3 is located in the hollow projection area of ​​the rotating component 2; the working end of the suction nozzle 3 can pick up the chip; the visual unit is located above the welding head unit and is arranged opposite to the hollow of the rotating component 2, and the visual unit can obtain an image.

[0031] The welding head mechanism of the chip placement machine of the present invention, the welding head unit includes a rotating component 2, the rotating component 2 can drive the suction nozzle 3 to rotate, thereby adjusting the position of the suction nozzle 3 in a plane perpendicular to the rotation axis of the rotating component 2, and at the same time, the rotating component 2 can reciprocate relative to the mounting base 1 in a direction parallel to the rotation axis, so that the suction nozzle 3 can adjust its position in space, and the suction nozzle 3 can pick up the chip, thereby realizing the movement of the chip. The present invention utilizes the rotating component 2 and the mounting base 1 to cooperate with each other to improve the movement accuracy of the welding head unit and ensure the smooth progress of the patch; at the same time, the rotating component 2 of the present invention is a hollow structure, the working end of the suction nozzle 3 is located below the hollow part of the rotating component 2, and the visual unit is located above the hollow part of the rotating component 2, so that the visual component can obtain images of the suction nozzle 3, the chip and the patch position, thereby improving the visual compensation accuracy, and combining with the welding head unit to drive the suction nozzle 3 to move precisely, thereby effectively improving the patch accuracy.

[0032] Specifically, the rotating assembly 2 includes a mounting plate 4, a bearing seat 5, and a driver 6. The mounting plate 4 is rotatably mounted on the bearing seat 5. The bearing seat 5 is slidably mounted on the mounting seat 1. The suction nozzle 3 is mounted on the mounting plate 4. The driver 6 is fixed to the bearing seat 5. The driver 6 is connected to the mounting plate 4 by transmission. The driver 6 drives the mounting plate 4 to rotate, and then uses the mounting plate 4 to drive the suction nozzle 3 to rotate, adjusting the position of the working end of the suction nozzle 3. The bearing seat 5 and the mounting plate 4 are both hollow structures, so that the visual unit can use the hollow structure of the rotating assembly 2 to acquire images. The driver 6 can be a motor. In this specific embodiment, a hollow cup motor is selected. In actual applications, other types of drive structures can also be selected according to specific working conditions to meet different production requirements.

[0033] In other specific embodiments of the present invention, the mounting base 1 is connected to an adjustment mounting plate 24 to facilitate the connection of the welding head mechanism with other structures of the placement machine, and the connection position of the mounting base 1 and the adjustment mounting plate 24 can be adjusted, reducing the difficulty of assembly and improving the flexibility and adaptability of the mechanism.

[0034] In this specific embodiment, the suction nozzle 3 is an inclined structure, one end of the suction nozzle 3 is connected to the mounting disk 4, and the other end of the suction nozzle 3 extends to the rotation axis of the mounting disk 4. The suction nozzle 3 is set to an inclined structure, which facilitates the connection between the suction nozzle 3 and the mounting disk 4 while allowing the working end of the suction nozzle 3 to extend into the projection area of ​​the hollow structure of the rotating component 2, so that the visual unit can smoothly obtain images of the working end, chip and patch position, thereby facilitating the patch work and improving the patch accuracy.

[0035] In order to improve the rotation smoothness of the mounting disk 4, a disc bearing 7 is provided between the mounting disk 4 and the bearing seat 5. The disc bearing 7 is also a hollow structure. In practical applications, a suitable type of bearing can be selected according to actual working conditions.

[0036] At the same time, the rotating assembly 2 also includes a bushing 8. The output end of the driver 6 is transmission-connected to the bushing 8. The bushing 8 is connected to the mounting plate 4. The provision of the bushing 8 ensures smooth transmission of power. The bushing 8 is a hollow structure.

[0037] In addition, the rotating assembly 2 further includes a driving wheel 9 and a driven wheel 10. The driver 6 is connected to the driving wheel 9. The driving wheel 9 drives the driven wheel 10 to rotate using a transmission belt. The driven wheel 10 is connected to the bushing 8 and has a hollow structure. In other specific embodiments of the present invention, a transmission mechanism such as a sprocket chain or a gear ring can also be selected to improve the flexibility and adaptability of the rotating assembly 2.

[0038] It should also be noted that the rotation axis of the rotating component 2 coincides with the axis of the hollow structure of the rotating component 2, so that in the process of the rotating component 2 driving the suction nozzle 3 to rotate, the working end of the suction nozzle 3 is always located at the center of the hollow projection area of ​​the rotating component 2, which is convenient for the visual unit to obtain the image; in other specific embodiments of the present invention, the specifications of the hollow structure of the rotating component 2 and the relationship between it and the rotation axis of the rotating component 2 can also be reasonably set according to the patch requirements to further improve the adaptability of the mechanism.

[0039] More specifically, the SMT welding head mechanism of the present invention also includes an air circuit component, and the suction nozzle 3 is connected to the external air source 12 via the air circuit component. The suction nozzle 3 can adsorb the chip, and the external air source 12 uses the air circuit component to vacuum the suction nozzle 3 so that it can adsorb and pick up the chip.

[0040] Among them, the air circuit component includes a low-friction cylinder 11, and the suction nozzle 3 is connected to the external air source 12 by means of the low-friction cylinder 11. The low-friction cylinder 11 is used to output the chip-picking pressure and transmit it to the suction nozzle 3, so that the pressure of the suction nozzle 3 when picking up the chip can be controlled. The use of the low-friction cylinder 11 can also reduce the friction of the mechanism. A control valve is set between the low-friction cylinder 11 and the external air source 12. The control valve includes an electric proportional valve and a solenoid valve. The compressed gas delivered by the external air source 12 is pressure-regulated by the electric proportional valve, and then the compressed gas is opened by the solenoid valve to allow the compressed gas to enter the low-friction cylinder 11, and the low-friction cylinder 11 delivers the chip-picking pressure to the suction nozzle 3. It should be emphasized that in this specific embodiment, the number of control valves is multiple groups, and each group of control valves includes an electric proportional valve and a solenoid valve. The parameters of the electric proportional valve of each group of control valves are different. Multiple groups of control valves are set in parallel to facilitate the adjustment of the chip-picking pressure of the suction nozzle 3. See for details. Figure 4The compressed air delivered by the external air source 12 is adjusted to the pressure when the welding head mechanism picks up the chip through the first electrical proportional valve 13, the compressed air is adjusted to the pressure when the welding head mechanism is running through the second electrical proportional valve 15, and is adjusted to the pressure when the welding head mechanism is pasting the chip through the third electrical proportional valve 17. When the welding head mechanism picks up the chip, the first solenoid valve 14 opens, the second solenoid valve 16 and the third solenoid valve 18 are closed, and the low friction cylinder 11 outputs the chip picking pressure to the suction nozzle 3 to achieve the pressure when the welding head mechanism picks up the chip; when the chip is picked up, the welding head mechanism moves to the chip pasting position, the second solenoid valve 16 opens, the first solenoid valve 14 and the third solenoid valve 18 are closed, and the low friction cylinder 11 outputs the welding head mechanism movement pressure to the suction nozzle 3 to achieve the pressure when the welding head mechanism is running; when the welding head mechanism pastes the chip, the third solenoid valve 18 opens, the first solenoid valve 14 and the second solenoid valve 16 are closed, and the low friction cylinder 11 outputs the chip pasting pressure to the suction nozzle 3 to achieve the pressure when the welding head mechanism pastes the chip. The device utilizes multiple control valves, with the solenoid valves switching to electrical signals. The air path connecting the solenoid valves to the low-friction cylinder 11 is very short, enabling force switching during high-speed motion and ensuring the proper operation of the welding head mechanism. Prior art welding head patch pressure control often utilizes spring control or single cylinder control. Switching patch pressure is not only complex but also time-consuming. The welding head mechanism of the present invention utilizes three control valves to enable rapid switching between different operating pressures.

[0041] In order to facilitate the monitoring of the working pressure of the welding head mechanism, the air circuit assembly also includes a pressure sensor 19, which uses the pressure sensor 19 to provide real-time feedback on the working pressure and closed-loop control, thereby accurately controlling the welding head patch pressure, making it convenient for the operator to monitor in real time whether the pressure situation meets production requirements, and further improving the controllability of the welding head mechanism.

[0042] It should also be noted that an air bearing 20 is arranged between the rotating component 2 and the mounting seat 1. The air bearing 20 is connected to the external air source 12. The air bearing 20 is used to drive the rotating component 2 to reciprocate along the axial direction of the rotating component 2 to adjust the position. Using the air bearing 20 to adjust the position can also reduce the friction of the welding head mechanism. There are two air bearings 20, which improves the force uniformity of the rotating component 2; an elastic member 21 is also provided between the rotating component 2 and the mounting seat 1 to assist in controlling the patch pressure and facilitate reset. The elastic member 21 can be a compression spring, which is easy to install and the spring is inexpensive, which is conducive to saving production costs.

[0043] In actual application, in order to facilitate the connection between the external gas source 12 and the welding head mechanism, a vacuum joint 22 and an adapter joint 23 can be set. The suction nozzle 3 is connected to the external gas source 12 using the vacuum joint 22, and the air bearing 20 is connected to the external gas source 12 using the adapter joint 23 to ensure pressure transmission.

[0044] The soldering head mechanism of the chip mounter of the present invention has a hollow structure of the rotating assembly 2 as a whole, so that the visual unit can obtain images of the chip and the patch position, and the soldering head unit can pick up the chip and adjust the position of the chip. At the same time, according to the obtained images of the chip and the patch position, the position information of the chip is corrected in real time to improve the patch accuracy. At the same time, the present invention controls the working pressure of the soldering head mechanism through multiple groups of control valves, realizes seamless switching of the patch pressure, and solves the problem in the prior art that the cylinder cannot quickly adjust the input pressure. In addition, the friction of the mechanism is reduced by using the low-friction cylinder 11 and the air bearing 20, so that the patch pressure can be controlled more accurately, and in actual application, the accuracy of ±1g (here g is the unit of pressure) can be achieved.

[0045] The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only intended to help understand the method and core concept of the present invention. At the same time, those skilled in the art will find that the specific implementation methods and application scopes may vary based on the concept of the present invention. In summary, the contents of this specification should not be construed as limiting the present invention.

Claims

1. A chip placement machine welding head mechanism, characterized in that: include: The welding head unit includes a mounting base, a rotating assembly and a suction nozzle, the rotating assembly is slidably arranged on the mounting base, the suction nozzle is arranged on the rotating assembly, the rotating assembly can drive the suction nozzle to rotate, the rotating assembly is a hollow structure, and the rotation axis of the rotating assembly is located in the hollow of the rotating assembly, and the rotation axis of the rotating assembly is parallel to the reciprocating sliding direction of the rotating assembly; the suction nozzle has a working end, and in a plane perpendicular to the rotation axis of the rotating assembly, the projection of the working end is located in the hollow projection area of ​​the rotating assembly; the working end can pick up the chip; A visual unit, located above the welding head unit and facing the hollow portion of the rotating assembly, capable of acquiring images; The rotating assembly includes a mounting plate, a bearing seat and a driver. The mounting plate is rotatably arranged on the bearing seat, the bearing seat is slidably arranged on the mounting seat, the suction nozzle is arranged on the mounting plate, the driver is fixed on the bearing seat, and the driver is transmission-connected to the mounting plate. The bearing seat and the mounting plate are both hollow structures. The suction nozzle is an inclined structure, one end of the suction nozzle is connected to the mounting plate, and the other end of the suction nozzle extends to the rotation axis of the mounting plate; An elastic member is further provided between the rotating assembly and the mounting seat.

2. The chip placement machine welding head mechanism according to claim 1, characterized in that: A disc bearing is arranged between the mounting plate and the bearing seat.

3. The chip placement machine welding head mechanism according to claim 2, characterized in that: The rotating assembly further includes a bushing, the output end of the driver is transmission-connected to the bushing, the bushing is connected to the mounting plate, and the bushing is a hollow structure.

4. The chip placement machine welding head mechanism according to claim 3, characterized in that: The rotating assembly further includes a driving wheel and a driven wheel. The driver is connected to the driving wheel. The driving wheel drives the driven wheel to rotate using a transmission belt. The driven wheel is connected to the bushing and is a hollow structure.

5. The chip placement machine welding head mechanism according to any one of claims 1 to 4, characterized in that: The rotation axis of the rotating assembly coincides with the axis of the hollow structure of the rotating assembly.

6. The chip placement machine welding head mechanism according to any one of claims 1 to 4, characterized in that: It also includes an air circuit component, and the suction nozzle is connected to an external air source through the air circuit component, and the suction nozzle can adsorb the chip.

7. The chip placement machine welding head mechanism according to claim 6, characterized in that: The air circuit assembly includes a low-friction cylinder, the suction nozzle is connected to the external air source via the low-friction cylinder, and a control valve is provided between the low-friction cylinder and the external air source.

8. The chip placement machine welding head mechanism according to claim 6, characterized in that: An air bearing is provided between the rotating assembly and the mounting seat, and the air bearing is connected to the external air source.

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