A double force control placement head based on cylinder force control and control method

Abstract

The present invention discloses a dual force control placement head based on cylinder force control and a control method, which comprises a mounting plate, a mounting cylinder seat fixed below the mounting plate, a motor fixed above the mounting plate, a diaphragm bracket driven by the motor to rotate, an elastic diaphragm fixedly mounted on the diaphragm bracket, a connecting rod hung at the top of the elastic diaphragm center, a cylinder assembly mounted in the mounting cylinder seat and surrounding the connecting rod, a rotating placement shaft located below the cylinder assembly and fixedly connected to the bottom of the connecting rod, an air-floating sleeve mounted in the mounting cylinder seat and surrounding the rotating placement shaft, a force transmission member located above the air-floating sleeve and fixed on the rotating placement shaft, and a micro-pressure sensing module fixed on the mounting cylinder seat and monitoring the axial pressure and axial displacement of the force transmission member. The present invention can directly act on the axis placement pressure control of the rotating placement shaft, and effectively solve the problem of overpressure caused by the time required for the pressure sensor to respond.

Description

Technical Field

[0001] The invention belongs to the technical field of mounting equipment, and in particular relates to a double-force-controlled mounting head based on cylinder force control and a control method. Background Art

[0002] In recent years, with the increase in communication speed requirements, chip components have been miniaturized, products have been integrated with high density, and production process requirements and reliability have become increasingly higher. The continuous innovation of various packaging and patch process technologies has also provided a basis for the integrated manufacturing of smaller and thinner chips. Among them, surface mount technology is a comprehensive technology that has emerged with the development, involving electronic component welding and assembly technology. In the placement equipment, the most important key component is the placement head. In order to monitor the placement pressure in real time, a pressure control device that monitors the placement pressure in the placement head is essential.

[0003] In order to control the mounting pressure for various precision ranges, CN116981244B in the prior art discloses a dual-pressure controlled mounting head, which uses a micro-pressure sensing module to control the axial tiny pressure of the mounting rotating shaft, and uses a pressure sensor with a large measuring range to control the axial large force, thereby realizing dual force control. However, when performing large force control, during the mounting process, when the mounting pressure is greater than the set threshold, the pressure sensor first collects the mounting pressure and then transmits it to the control system. The control system performs command control of the mounting action by comparing the feedback output, and stops further increasing the mounting force. However, the entire process also takes time to process, which makes the control response speed slow and prone to overpressure.

[0004] Therefore, it is necessary to provide a new dual-force-controlled placement head based on cylinder force control to solve the above technical problems. Summary of the invention

[0005] One of the main purposes of the present invention is to provide a dual force control placement head based on cylinder force control, which can directly act on the axis placement pressure control of the rotating placement axis, and effectively solve the problem of overpressure caused by the time required for the pressure sensor to respond.

[0006] The present invention achieves the above-mentioned purpose through the following technical scheme: a double force control placement head based on cylinder force control, which includes a mounting plate, a mounting cylinder seat fixed below the mounting plate, a motor fixed above the mounting plate, a diaphragm bracket rotatably arranged on the mounting plate and driven to rotate by the motor, an elastic diaphragm fixedly mounted on the diaphragm bracket, a connecting rod hung at the top at the center of the elastic diaphragm and capable of axially floating up and down, a cylinder assembly installed in the mounting cylinder seat and surrounding the connecting rod, a rotating placement shaft located below the cylinder assembly and fixedly connected to the bottom of the connecting rod, an air-floating sleeve installed in the mounting cylinder seat and surrounding the rotating placement shaft, a force transmission part located above the air-floating sleeve and fixed on the rotating placement shaft, and a micro-pressure sensing module fixed on the mounting cylinder seat and monitoring the axial pressure and axial displacement of the force transmission part, wherein a suction nozzle is provided at the end of the rotating placement shaft.

[0007] Furthermore, the cylinder assembly includes a cylinder barrel and a piston movably arranged up and down in the cylinder barrel, the lower surface of the piston presses the force transmission component downward, and the cylinder barrel has a movable space for the piston to move up and down.

[0008] Furthermore, the piston is a hollow structure and a channel is formed inside for the connecting rod to pass through.

[0009] Furthermore, the piston includes a piston body that cooperates with the interior of the cylinder and a cylinder body that extends upward from the upper surface of the piston body; the channel runs through the piston body and the cylinder body; the cylinder body extends upward to the outside of the cylinder and is sealed and connected to the top opening of the cylinder through a sealing ring.

[0010] Furthermore, a limit plate is provided below the cylinder barrel to limit the downward movement range of the piston.

[0011] Furthermore, the piston body and the internal cavity of the cylinder barrel form a sealed space, and the cylinder barrel is provided with an air nozzle connected to an external air source; the air nozzle is connected to the sealed space.

[0012] Furthermore, a pressure regulating valve is provided on a pipeline connecting the gas nozzle and the external gas source to ensure that the pressure value in the sealed space is maintained at a stable set pressure value state.

[0013] Furthermore, the force transmission component includes a disc portion that cooperates with the micro-pressure sensing module and a boss portion that cooperates with and interferes with the lower surface of the piston body; the upper surface of the disc portion forms a first contact surface that contacts the sensing end of the micro-pressure sensing module, and the upper surface of the boss portion forms a second contact surface that contacts the lower surface of the piston body, and the second contact surface has a height difference with the first contact surface and is located above the first contact surface.

[0014] Furthermore, in the initial state, the piston is located in a low position, and there is a set height difference between the second contact surface and the lower surface of the piston; before the rotating mounting shaft is axially compressed upward by the set height difference, the elastic diaphragm exerts force on the rotating mounting shaft, and the mounting pressure is monitored by the micro-pressure sensing module; when the upward displacement of the rotating mounting shaft exceeds the set height difference, the force transmission part fixed on the top of the rotating mounting shaft contacts the lower surface of the piston, and the cylinder assembly exerts force on the rotating mounting shaft, and the mounting pressure is controlled by the cylinder assembly.

[0015] Another object of the present invention is to provide a control method for the dual-force control placement head as described above, comprising:

[0016] (1) First range mounting pressure control: When the maximum allowable mounting pressure is within the first set range, the mounting pressure is monitored by monitoring the axial micro pressure of the rotating mounting shaft through the micro pressure sensing module;

[0017] (2) Second range mounting pressure control: When the maximum allowable mounting pressure is within the second set range, the axial pressure of the rotating mounting axis is controlled by the pressure inside the cylinder assembly, and the micro-pressure sensing module is used to monitor the axial displacement of the rotating mounting axis to ensure that it is within the allowable range.

[0018] Compared with the prior art, the beneficial effects of the dual-force-controlled placement head and control method based on cylinder force control of the present invention are: within the placement force range of, for example, 0~200g, the axial pressure of the rotating placement shaft is sensed by the spring structure extending from the micro-pressure sensing module, so as to realize precise monitoring of the placement pressure within the small force range; within the placement force range of, for example, 2kg-20kg, the axial placement pressure of the rotating placement shaft is controlled by the stable air pressure inside the cylinder assembly, and when the placement pressure exceeds the set value, the piston inside the cylinder assembly will be pushed upward instantly to release the axial placement pressure of the rotating placement shaft, effectively solving the placement overpressure problem, and at the same time, the micro-pressure sensing module is used to monitor the axial displacement of the rotating placement shaft in real time to ensure that the placement pressure is always within the stable control range of the cylinder assembly, to ensure the stability of the output force of the cylinder assembly, and to realize the dual-force control function of the placement head. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a structural schematic diagram of an embodiment of the present invention;

[0020] Figure 2 It is a schematic diagram of the explosion structure of an embodiment of the present invention;

[0021] Figure 3 It is a structural schematic diagram of a force transmission component and a micro-pressure sensing module in an embodiment of the present invention;

[0022] Figure 4 It is a partial cross-sectional structural schematic diagram of an embodiment of the present invention;

[0023] The numbers in the figure represent:

[0024] 100-Dual force control placement head based on cylinder force control;

[0025] 1-mounting plate; 2-mounting cylinder seat; 3-motor; 4-diaphragm bracket; 5-elastic diaphragm; 6-connecting rod; 7-cylinder assembly, 71-cylinder barrel, 72-piston, 721-channel, 722-piston body, 723-cylinder body, 73-sealed space, 74-air nozzle; 8-rotating mounting shaft; 9-air floating sleeve; 10-force transmission part, 101-disc part, 102-boss part, 103-first contact surface, 104-second contact surface; 11-micro pressure sensing module; 12-motor support; 13-coupling; 14-bearing; 15-sealing ring; 16-limiting plate; 17-suction nozzle. DETAILED DESCRIPTION

[0026] Embodiment 1:

[0027] Please refer to Figure 1-Figure 4 This embodiment is a dual force control placement head 100 based on cylinder force control, which includes a mounting plate 1, a mounting cylinder seat 2 fixed below the mounting plate 1, a motor 3 fixed above the mounting plate 1, a diaphragm bracket 4 rotatably arranged on the mounting plate 1 and driven to rotate by the motor 3, an elastic diaphragm 5 fixedly mounted on the diaphragm bracket 4, a connecting rod 6 suspended at the top at the center of the elastic diaphragm 5 and capable of axially floating up and down, a cylinder assembly 7 mounted in the mounting cylinder seat 2 and surrounding the connecting rod 6, a rotating placement shaft 8 located below the cylinder assembly 7 and fixedly connected to the bottom of the connecting rod 6, an air-floating sleeve 9 mounted in the mounting cylinder seat 2 and surrounding the rotating placement shaft 8, a force transmission member 10 located above the air-floating sleeve 9 and fixed on the rotating placement shaft 8, and a micro-pressure sensing module 11 fixed on the mounting cylinder seat 2 and monitoring the axial pressure of the force transmission member 10. A suction nozzle 17 is provided at the end of the rotating placement shaft 8.

[0028] The cylinder assembly 7 includes a cylinder 71 and a piston 72 that is movably arranged up and down in the cylinder 71. The lower surface of the piston 72 presses the force transmission member 10 downward, and there is a movable space in the cylinder 71 for the piston 72 to move up and down. A set amount of gas is filled into the cylinder 71 so that the inside of the cylinder 71 reaches a set air pressure, thereby generating a set pressure F1 for the piston 72. The set pressure F1 can be set according to the maximum mounting pressure during mounting, and F1 will be maintained above the force transmission member 10. When the rotating mounting shaft 8 is used for chip mounting, it is subjected to an axial upward counter pressure. If the counter pressure is greater than the set maximum mounting pressure, the piston 72 will be pushed upward by the force transmission member 10 to immediately release the axial upward counter pressure on the rotating mounting shaft 8, thereby improving the response speed of the overpressure control, thereby effectively avoiding the occurrence of overpressure during mounting.

[0029] The mounting plate 1 is provided with a motor support 12. The motor 3 is fixed on the motor support 12, and its rotating end is fixedly connected with the top end of the diaphragm support 4 through a coupling 13, thereby driving the diaphragm support 4 to rotate.

[0030] The diaphragm support 4 is rotatably mounted on the mounting plate 1 via the bearing 14. The structures of the diaphragm support 4 and the elastic diaphragm 5 are the same as those in the prior art patent CN116981244B, and will not be described in detail in this embodiment. The elastic diaphragm 5 mainly provides the axial floating function for the rotating mounting shaft 8.

[0031] The piston 72 is a hollow structure, and a vertically penetrating passage 721 is formed inside the piston 72 for the connecting rod 6 to pass through. In order to ensure the sealing of the internal cavity of the cylinder 71, the structure of the piston 72 is optimized in this embodiment. The piston 72 includes a piston body 722 that cooperates with the inside of the cylinder 71 and a cylinder body 723 that extends upward from the upper surface of the piston body 722. The cylinder body 723 extends upward to the outside of the cylinder 71 and is sealed with the top opening of the cylinder 71 through a sealing ring 15. A limit plate 16 is provided below the cylinder 71 to limit the downward range of movement of the piston 72. The piston body 722 and the internal cavity of the cylinder 71 form a sealed space 73. Under the action of the air pressure inside the sealed space 73, the piston body 722 is pressed against the limit plate 16. The cylinder 71 is provided with an air nozzle 74 connected to an external air source, and a pressure regulating valve is provided on the pipeline connecting the air nozzle 74 and the external air source to ensure that the pressure value in the sealed space 73 is maintained at a stable set pressure value state; the air nozzle 74 is connected to the sealed space 73.

[0032] The force transmission member 10 includes a disc portion 101 that cooperates with the micro-pressure sensing module 11 and a boss portion 102 that cooperates with and contacts the lower surface of the piston body 722. The upper surface of the disc portion 101 forms a first contact surface 103 that contacts the sensing end of the micro-pressure sensing module 11, and the upper surface of the boss portion 102 forms a second contact surface 104 that contacts the lower surface of the piston body 722. The second contact surface 104 has a height difference with the first contact surface 103 and is located above the first contact surface 103, ensuring that the micro-pressure sensing module 11 and the cylinder assembly 7 can successively achieve mounting pressure control within different force ranges.

[0033] The structure of the micro-pressure sensing module 11 is the same as that in the prior art patent CN116981244B, and will not be described in detail in this embodiment. The air-floating sleeve 9 can adopt the existing structure on the market, and will not be described in detail in this embodiment. The air-floating sleeve 9 provides axial sliding support for the rotating mounting shaft 8. Compared with the slide rail slider structure, the friction force is eliminated. With the micro-pressure sensing module 11, the pressure generated by a weight within 10g can be controlled with a small force, which is about 0.098N, expanding the scope of application.

[0034] In the initial state, the piston 72 is located in a low position, and there is a set height difference between the second contact surface 104 and the lower surface of the piston 72. For example, the set height difference is 0.5 mm. Before the rotating mounting shaft 8 is axially compressed upward by 0.5 mm, the elastic diaphragm 5 exerts force on the rotating mounting shaft 8, and the mounting pressure is accurately monitored by the micro-pressure sensing module 11.

[0035] When the rotating mounting shaft 8 is displaced upward beyond the set height difference, the boss portion 102 in the force transmission member 10 fixed on the top of the rotating mounting shaft 8 contacts the lower surface of the piston body 722, and the cylinder assembly 7 exerts force on the rotating mounting shaft 8, and the mounting pressure is accurately monitored by the cylinder assembly 7. The cylinder assembly 7 can realize the pressure control generated by weights in the range of 2kg to 20kg, which greatly improves the pressure control range of the mounting head. Since the greater the axial compression of the elastic diaphragm 5, the greater the elastic axial pressure generated, in order to prevent the elastic diaphragm 5 from being over-compressed, therefore, in the pressure control process of the cylinder assembly 7, this embodiment uses the micro-pressure sensing module 11 to simultaneously monitor the axial displacement distance of the rotating mounting shaft 8 to prevent the elastic diaphragm 5 from being compressed excessively, thereby ensuring the stability of the output force of the cylinder assembly 7.

[0036] This embodiment also provides a control method for a dual force control placement head based on cylinder force control, which includes:

[0037] (1) First range mounting pressure control: When the maximum allowable mounting pressure is within the first range, the mounting pressure is monitored by monitoring the axial micro pressure of the rotating mounting shaft 8 through the micro pressure sensing module 11;

[0038] (2) Second range mounting pressure control: When the maximum allowable mounting pressure is within the second range, the axial pressure of the rotating mounting shaft 8 is controlled by the pressure inside the cylinder assembly 7, and the micro-pressure sensing module 11 is used to monitor the axial displacement of the rotating mounting shaft 8 within the allowable range.

[0039] For those skilled in the art, several modifications and improvements can be made without departing from the inventive concept of the present invention, all of which fall within the protection scope of the present invention.

Claims

1. A dual force control placement head based on cylinder force control, characterized in that: The utility model comprises a mounting plate, a mounting cylinder seat fixed below the mounting plate, a motor fixed above the mounting plate, a diaphragm bracket rotatably arranged on the mounting plate and driven to rotate by the motor, an elastic diaphragm fixedly arranged on the diaphragm bracket, a connecting rod with a top hung at the center of the elastic diaphragm and capable of axially floating up and down, a cylinder assembly mounted in the mounting cylinder seat and surrounding the connecting rod, a rotating mounting shaft located below the cylinder assembly and fixedly connected to the bottom of the connecting rod, an air-floating sleeve mounted in the mounting cylinder seat and surrounding the rotating mounting shaft, a force transmission part located above the air-floating sleeve and fixed on the rotating mounting shaft, and a micro-pressure sensing module fixed on the mounting cylinder seat and monitoring the axial pressure and axial displacement of the force transmission part, wherein a suction nozzle is arranged at the end of the rotating mounting shaft; The cylinder assembly comprises a cylinder and a piston movably arranged in the cylinder, the lower surface of the piston presses the force transmission member downward, and the cylinder has a movable space for the piston to move up and down; the piston is a hollow structure and has a channel formed inside for the connecting rod to pass through; the piston comprises a piston body matched with the inside of the cylinder and a barrel extending upward from the upper surface of the piston body; the channel runs through the piston body and the barrel; the barrel extends upward to the outside of the cylinder and is sealed and connected to the top opening of the cylinder through a sealing ring; The force transmission member includes a disc portion matched with the micro-pressure sensing module and a boss portion matched with and in conflict with the lower surface of the piston body; the upper surface of the disc portion forms a first contact surface contacting the sensing end of the micro-pressure sensing module, and the upper surface of the boss portion forms a second contact surface contacting the lower surface of the piston body, and the second contact surface has a height difference with the first contact surface and is located above the first contact surface; In the initial state, the piston is located in a low position, and there is a set height difference between the second contact surface and the lower surface of the piston; before the rotating mounting shaft is axially compressed upward by the set height difference, the elastic diaphragm exerts force on the rotating mounting shaft, and the mounting pressure is monitored by the micro-pressure sensing module; when the rotating mounting shaft is displaced upward by more than the set height difference, the force transmission part fixed on the top of the rotating mounting shaft contacts the lower surface of the piston, and the cylinder assembly exerts force on the rotating mounting shaft, and the mounting pressure is controlled by the cylinder assembly.

2. The dual force control placement head based on cylinder force control as claimed in claim 1, characterized in that: A limit plate is arranged below the cylinder barrel to limit the downward movement range of the piston.

3. The dual force control placement head based on cylinder force control as claimed in claim 1, characterized in that: The piston body and the inner cavity of the cylinder barrel form a sealed space, and the cylinder barrel is provided with an air nozzle connected to an external air source; the air nozzle is connected to the sealed space.

4. The dual force control placement head based on cylinder force control as claimed in claim 3, characterized in that: A pressure regulating valve is arranged on the pipeline connecting the air nozzle and the external air source to stabilize the pressure value in the sealed space at a set pressure value.

5. A control method for a dual force control placement head as claimed in claim 1, characterized in that: It includes: (1) First range mounting pressure control: When the maximum allowable mounting pressure is within the first set range, the mounting pressure is monitored by monitoring the axial micro pressure of the rotating mounting shaft through the micro pressure sensing module; (2) Second range mounting pressure control: When the maximum allowable mounting pressure is within the second set range, the axial pressure of the rotating mounting axis is controlled by the pressure inside the cylinder assembly, and the micro-pressure sensing module is used to monitor the axial displacement of the rotating mounting axis to ensure that it is within the allowable range.

Images