Surface mounting head assembly for aligning rotation center based on direct drive technology

Abstract

The invention discloses a mounting head assembly based on direct-drive technology rotation center alignment, which comprises a shell, a direct-drive rotating platform is arranged in the shell, and the direct-drive rotating platform is connected with a force control mounting head; the force control mounting head comprises a first connecting block, a suction nozzle mounting seat and at least one elastic piece, and the first connecting block and the suction nozzle mounting seat are connected to two opposite ends of the elastic piece; the first connecting block is fixedly connected to the direct-driven rotating platform; a suction nozzle assembly is arranged below the suction nozzle mounting base, a sensing block is arranged at the position, protruding out of the elastic piece, of the suction nozzle mounting base, and a displacement sensor which is connected to the direct-drive rotating platform and electrically connected with a controller of a mounting force control system is arranged over the sensing block. The displacement sensor is used for detecting the deformation displacement amount of the elastic piece connected with the mounting head and feeding back the deformation displacement amount to the controller, and only the suction nozzle mounting seat and the suction nozzle assembly are arranged on the elastic piece, so that the load pressure of the elastic piece is reduced, and the mounting pressure is controlled more accurately.

Description

Technical Field

[0001] The invention relates to a mounting head assembly for slewing center alignment based on direct drive technology, belonging to the technical field of automatic mounting equipment. Background Art

[0002] Most of the existing chip suction methods use vacuum nozzle suction. The common structure for realizing this function is: the rotary actuator is installed on the linear guide rail as a whole, the pressure control component connects the rotary actuator and the guide rail base, and the nozzle is installed at the front end of the rotary actuator. When the nozzle carries the chip and contacts the carrier, the nozzle end will be pressed into the entire placement head assembly through the linear rail guide, generating a small displacement; the scale in the same direction as the linear rail feeds back the displacement information to the controller of the micro voice coil motor (in the pressure control component), and then uses the corresponding algorithm to control the voice coil motor to output the force pressing against the chip. In the above structure, since the movable part installed on the linear guide rail includes components such as the motor driving the rotation and the scale for feedback of the rotation angle, the pressure control component needs to drive a heavy load. When the entire placement device moves at high speed, the pressure control component needs to output a reverse torque to prevent the load on the linear guide rail from moving due to high-speed operation, thereby keeping the load relatively still. However, the high inertia of the load requires the reverse output torque to match it, which leads to the pressure control component requiring a higher specification motor to meet the demand.

[0003] This structure ultimately results in a large mass of the overall device, slow force control response speed, poor force control accuracy, and poor control accuracy of the height position of the nozzle end feedback during force control. In addition, in order to reduce the weight impact, the nozzle head with a rotating function needs to adopt an extremely light and complex design structure. Such harsh conditions make it difficult to meet the requirements of high-precision rotation.

[0004] Secondly, in the actual production process, a visual system is required to observe the position of the patch area and compare it with the real-time position of the chip on the nozzle head determined through the nozzle observation window for high-precision alignment and placement. However, the observation window component needs to be placed closest to the nozzle end, which has a certain volume and occupies space, and the rotation of the nozzle also requires a motor or belt drive rotation, which will also occupy the best space near the nozzle end. Therefore, in the existing solution, these two structures have a certain conflict and it is difficult to take both into account. A common solution is to use a special nozzle and nozzle seat mechanism with an observation window to replace the rotary actuator of the aforementioned structure, but such a structure loses the ability of the placement device to compensate for the chip angle error during the placement process.

[0005] In addition, the above structures all use micro linear guides as motion guides to guide the nozzle to move up and down. The placement accuracy of this type of structure is not only affected by the accuracy of the motion axis, but also by the gap interference of the micro linear guide, making the final placement accuracy unsatisfactory. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to provide a mounting head assembly for aligning the center of rotation based on direct drive technology. The rotation of the mounting head is driven by a direct drive rotating platform. A displacement sensor is used to detect the deformation displacement of an elastic member connected to the mounting head and feedback it to the controller. Only a nozzle mounting base and a nozzle assembly are provided on the elastic member, which maximally reduces the load pressure on the elastic member, so that the mounting pressure can be controlled more precisely.

[0007] In order to solve the above technical problems, the technical solution adopted by the present invention is as follows:

[0008] A mounting head assembly for aligning the center of rotation based on direct drive technology, including a housing. A direct drive rotating platform is arranged inside the housing, and a force-controlled mounting head is connected to the direct drive rotating platform. The force-controlled mounting head includes a first connection block, a nozzle mounting base and at least one elastic member. Among them, the first connection block and the nozzle mounting base are connected to opposite ends of the elastic member; the first connection block is fixedly connected to the direct drive rotating platform; a nozzle assembly is arranged below the nozzle mounting base, and an induction block is arranged at a position where the nozzle mounting base protrudes from the elastic member. A displacement sensor fixedly connected to the direct drive rotating platform is arranged directly above the induction block, and the displacement sensor is electrically connected to the controller of the mounting force control system.

[0009] The aforementioned mounting head assembly for aligning the center of rotation based on direct drive technology is characterized in that: the force-controlled mounting head includes two elastic members with the same shape, and the elastic members are metal shrapnel. The first connection block and the nozzle mounting base are clamped between the two elastic members with the same shape, and gaskets are arranged at the connection positions of the upper surface of the upper elastic member, the lower surface of the lower elastic member with the first connection block and the nozzle mounting base for fixed connection.

[0010] The aforementioned mounting head assembly for aligning the center of rotation based on direct drive technology is characterized in that: a limiting block located on the nozzle mounting base is arranged below the induction block, and a support block connected to the direct drive rotating platform and in contact with the limiting block is arranged directly below the limiting block.

[0011] The aforementioned mounting head assembly for aligning the center of rotation based on direct drive technology is characterized in that: a second connection block is fixedly connected to the direct drive rotating platform, a turntable is fixedly connected to the second connection block, a third connection block is arranged on the turntable, the support block is arranged on the third connection block, and the support block can be adjusted up and down relative to the third connection block.

[0012] The foregoing pick-and-place head assembly for aligning the center of rotation based on direct drive technology is characterized in that: the elastic member is of a square frame structure, a through hole is provided in the part of the nozzle mounting seat located inside the square of the elastic member, the upper end of the through hole is sealed by a lens, a suction hole paired with the through hole is provided at the top of the nozzle assembly, a first vacuum suction hole communicated with the through hole is provided on the nozzle mounting seat, a cover plate connected to the housing is provided above the direct drive rotary platform, the direct drive rotary platform is of a hollow annular structure, and an observation hole corresponding to the position of the lens is provided on the cover plate.

[0013] The foregoing pick-and-place head assembly for aligning the center of rotation based on direct drive technology is characterized in that: the shapes and sizes of the top of the nozzle assembly and the bottom of the nozzle mounting seat are the same, and a cavity is provided outside the suction hole, and a second vacuum suction hole capable of communicating with the cavity is provided at the bottom of the nozzle mounting seat.

[0014] The foregoing pick-and-place head assembly for aligning the center of rotation based on direct drive technology is characterized in that: adjusting bolts for adjusting its level relative to the housing are respectively provided at the diagonal corners of the direct drive rotary platform.

[0015] The foregoing pick-and-place head assembly for aligning the center of rotation based on direct drive technology is characterized in that: the displacement sensor is fixedly connected to the direct drive rotary platform through a fourth connecting block, and a waist-shaped groove is provided on the connecting surface of the fourth connecting block.

[0016] The foregoing pick-and-place head assembly for aligning the center of rotation based on direct drive technology is characterized in that: an angle position feedback grating scale structure for detecting its rotation angle is provided above the direct drive rotary platform.

[0017] The beneficial effects of the present invention are:

[0018] 1. By adopting a direct drive rotary platform to drive the rotation of the pick-and-place head assembly, when pick-and-place is performed, the deformation amount of the elastic member connected to the nozzle mounting seat is detected by the sensor, and the minute displacement amount of the nozzle each time is detected in real time, so as to well control the pick-and-place pressure, and each time it can stably and accurately return to the original position by using the elastic force of the elastic member, and this drive structure fundamentally solves the problem of reduced accuracy caused by mechanical clearances introduced by linear guide rails in traditional pick-and-place heads;

[0019] 2. By using two elastic members with the same shape to clamp and fix the nozzle mounting seat, when the chip on the nozzle assembly connected below the nozzle mounting seat is subjected to pick-and-place pressure, since one end of the two elastic members is fixed, it is ensured that the nozzle mounting seat moves up and down horizontally under the clamping of the elastic members, so as to also ensure that the chip on the nozzle assembly always remains horizontal during the pick-and-place process, ensuring uniform pick-and-place pressure;

[0020] 3. Only the nozzle mounting base and the nozzle assembly are fixedly connected to the elastic member, which minimizes the load on the elastic member, enables the mobile end of the force control system to be extremely lightweight, and improves the response speed of force control.

[0021] 4. By using a direct drive rotary platform to drive the rotation of the placement head assembly, combined with the observation lens on the nozzle mounting base, it is easy to observe the surface characteristics of the adsorbed chip from inside the nozzle assembly. Moreover, the nozzle assembly is adsorbed onto the nozzle mounting base using vacuum adsorption, ensuring that the observation window of the nozzle mounting base remains relatively stationary with respect to the nozzle assembly. At the same time, the placement head is mounted below the direct drive rotary platform, aligning the nozzle center with the rotation center to ensure that the chip does not exceed the field of view of the vision system during rotation. Additionally, a high-precision angular position feedback grating scale structure is used to feedback the rotation state of the direct drive rotary platform, achieving high-precision rotation and visual real-time alignment. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 is the front view of a placement head assembly for aligning the rotation center based on direct drive technology according to the present invention;

[0023] Figure 2 is the front elevation view of a placement head assembly for aligning the rotation center based on direct drive technology according to the present invention;

[0024] Figure 3 is Figure 2 the sectional view taken along A-A in

[0025] Figure 4 is Figure 3 the enlarged schematic view of A in

[0026] Figure 5 is the schematic structural view of a placement head assembly for aligning the rotation center based on direct drive technology according to the present invention with the cover plate hidden;

[0027] Figure 6 is the exploded schematic view of a placement head assembly for aligning the rotation center based on direct drive technology according to the present invention with the cover plate hidden;

[0028] Figure 7 is the schematic structural view of the placement component part of a placement head assembly for aligning the rotation center based on direct drive technology according to the present invention;

[0029] Figure 8 is the front view of the force control part of the placement component part of a placement head assembly for aligning the rotation center based on direct drive technology according to the present invention;

[0030] Figure 9 is the bottom view of the force control part of the placement component part of a placement head assembly for aligning the rotation center based on direct drive technology according to the present invention;

[0031] Figure 10 This is the front view of the nozzle assembly of a pick-and-place head assembly for aligning the center of rotation based on direct drive technology in the present invention.

[0032] In the figure,

[0033] 10. Housing;

[0034] 20. Direct drive rotary platform; 21. Adjusting bolt;

[0035] 30. Force control pick-and-place head; 31. First connecting block; 32. Elastic member; 33. Nozzle mounting seat; 331. Induction block; 332. Limit block; 333. Second vacuum suction hole; 34. Nozzle assembly; 36. Lens; 37. Second connecting block; 38. Turntable; 39. Third connecting block; 391. Support block;

[0036] 40. Angle position feedback grating scale structure;

[0037] 50. Cover plate; 51. Observation hole;

[0038] 60. Displacement sensor; 61. Fourth connecting block. Detailed implementation manner

[0039] The present invention will be further described below in conjunction with the accompanying drawings of the specification.

[0040] As Figures 1 - 10 shown, a pick-and-place head assembly for aligning the center of rotation based on direct drive technology includes a housing 10. A direct drive rotary platform 20 is provided inside the housing 10, and a force control pick-and-place head 30 is connected to the direct drive rotary platform 20. The force control pick-and-place head 30 includes a first connecting block 31, a nozzle mounting seat 33, and at least one elastic member 32. Among them, the first connecting block 31 and the nozzle mounting seat 33 are connected to opposite ends of the elastic member 32. The first connecting block 31 is fixedly connected to the direct drive rotary platform 20. A nozzle assembly 34 is provided below the nozzle mounting seat 33, and an induction block 331 is provided at a position where the nozzle mounting seat 33 protrudes from the elastic member 32. A displacement sensor 60 fixedly connected to the direct drive rotary platform 20 is provided directly above the induction block 331. The displacement sensor 60 is electrically connected to the controller of the pick-and-place force control system.

[0041] During the chip mounting process, the movement of the entire mounting head assembly is driven by a three-axis drive mechanism. Inside the mounting head assembly, a direct drive rotary platform 20 is provided to drive the rotation of the nozzle assembly 34. When the nozzle assembly 34 picks up the chip to be mounted, the three-axis drive mechanism drives it to a set position. After adjusting the angle through the direct drive rotary platform 20, the three-axis drive mechanism drives the entire mounting head assembly to press down. During the pressing process, the elastic member 32 on the nozzle mounting seat 33 deforms, generating a small displacement. Then, a displacement sensor 60 is used to detect the displacement of the induction block 331 and feedback it to the mounting control system in real time, thereby controlling the three-axis drive mechanism to ensure precise control of the mounting pressure.

[0042] In the present invention, the direct drive rotary platform 20 drives the direct drive rotary platform 20. At the same time, only the nozzle mounting seat 33 and the nozzle assembly 34 are connected to the elastic member 32, reducing other loads such as rotating shafts, linear rails, and motors, minimizing the load on the elastic member 32, enabling the mobile end of the force control system to be extremely lightweight, and improving the response speed of the force control.

[0043] In this embodiment, the force control mounting head 30 includes two elastic members 32 with the same shape. The elastic member 32 is a metal spring sheet, and the first connection block 31 and the nozzle mounting seat 33 are clamped between the two elastic members 32 with the same shape. Gaskets are provided at the connection points between the upper surface of the upper elastic member 32, the lower surface of the lower elastic member 32, and the first connection block 31 and the nozzle mounting seat 33 for fixed connection.

[0044] The nozzle mounting seat 33 is clamped and fixed by two elastic members 32 with the same shape. The other end of the elastic member 32 is clamped to the first connection block 31 and then fixedly connected to the direct drive rotary platform 20, always maintaining a horizontal state. It should be noted that the thicknesses of the part of the first connection block 31 and the part of the nozzle mounting seat 33 clamped between the two elastic members 32 with the same shape are the same. In the initial state, neither of the upper and lower elastic members 32 undergoes any deformation. When the chip on the nozzle assembly 34 connected below the nozzle mounting seat 33 is subjected to a mounting pressure, since one end of the two elastic members 32 is completely fixed, it is ensured that the nozzle mounting seat 33 can only move up and down horizontally under the clamping of the upper and lower elastic members 32 (if the nozzle mounting seat 33 tilts, the nozzle mounting seat 33 needs to move relative to at least one elastic member 32 or the elastic member 32 is stretched. However, in this embodiment, the nozzle mounting seat 33 is fixedly connected to the elastic member 32, and the elastic member 32 is made of metal and will not be stretched under a small pressure). Thus, it is also ensured that the chip on the nozzle assembly remains horizontal during the mounting process, ensuring uniform mounting pressure.

[0045] A limiting block 332 is provided on the nozzle mounting base 33 below the induction block 331, and a support block 391 connected to the direct drive rotary platform 20 and in contact with the limiting block 332 is provided directly below the limiting block 332. Specifically, a second connecting block 37 is fixedly connected to the direct drive rotary platform 20, a turntable 38 is fixedly connected to the second connecting block 37, a third connecting block 39 is provided on the turntable 38, the support block 391 is provided on the third connecting block 39, and the support block 391 can be adjusted up and down relative to the third connecting block 39. Through the connection of the second connecting block 37, the turntable 38 and the third connecting block 39, the support block 391 provided on the third connecting block 39 rotates synchronously with the direct drive rotary platform 20. Since the first connecting block 31 and the nozzle mounting base 33 also rotate synchronously with the direct drive rotary platform 20, the support block 391 and the limiting block 332 are relatively stationary. By adjusting the position of the support block 391, it is ensured that in the initial state, under the action of the support block 391 and the limiting block 332, the elastic member 32 is not subjected to any force and does not undergo any deformation, facilitating subsequent displacement detection and rapid resetting.

[0046] The elastic member 32 is of a square frame structure. A through hole is provided in the part of the nozzle mounting base 33 located inside the square frame of the elastic member 32. The upper end of the through hole is sealed by a lens 36. A suction hole 341 paired with the through hole is provided at the top of the nozzle assembly 34. A first vacuum suction hole communicating with the through hole is provided on the nozzle mounting base 33. A cover plate 50 connected to the housing 10 is provided above the direct drive rotary platform 20. The direct drive rotary platform 20 is a hollow annular structure. An observation hole 51 corresponding to the position of the lens 36 is provided on the cover plate 50. The vision detection system above the pick-and-place head assembly can observe the situation of the surface of the chip sucked by the nozzle assembly 34 through the observation hole 51 and the lens 36. When it is determined that angle compensation is required, the direct drive rotary platform 20 is rotated, and the rotation angle is accurately controlled by using the angle position feedback grating scale structure 40 provided above the direct drive rotary platform (20).

[0047] The shape and size of the top of the nozzle assembly 34 are consistent with those of the bottom of the nozzle mounting base 33, and a cavity 342 is provided outside the suction hole 341. A second vacuum suction hole 333 that can communicate with the cavity 342 is provided at the bottom of the nozzle mounting base 33. By means of pumping air through the second vacuum suction hole 333, the nozzle assembly 34 can be quickly connected to the bottom of the nozzle mounting base 33 by means of vacuum adsorption.

[0048] Therefore, by adopting the direct-drive rotary platform 20 to drive the rotation of the placement head assembly, combined with the observation lens 36 on the nozzle mounting seat 33, it is easy to observe the surface features of the adsorbed chip from inside the nozzle assembly 34. Moreover, the nozzle assembly is adsorbed on the nozzle mounting seat by vacuum, ensuring that the observation window of the nozzle mounting seat remains relatively stationary with the nozzle assembly. At the same time, the placement head is mounted below the direct-drive rotary platform, aligning the nozzle center with the rotation center, ensuring that the chip will not exceed the visual field range of the vision system during rotation. And a high-precision angular position feedback grating scale structure is used to feedback the rotation state of the direct-drive rotary platform, achieving high-precision rotation and visual real-time alignment.

[0049] Adjusting bolts 21 for adjusting its level relative to the housing 10 are respectively provided at the diagonal corners of the direct-drive rotary platform 20. In the initial state, the level of the direct-drive rotary platform 20 can be adjusted through the adjusting bolts 21, thereby adjusting the level of the nozzle assembly 34.

[0050] The displacement sensor 60 is fixedly connected to the direct-drive rotary platform 20 through the fourth connecting block 61 to achieve synchronous rotation of the two. And a waist-shaped groove is provided on the connecting surface of the fourth connecting block 61, facilitating the adjustment of the installation height during assembly.

[0051] A placement method for a placement head assembly with rotary center alignment based on direct-drive technology includes the following steps:

[0052] (1) After the placement head assembly picks up the chip to be placed, it is moved to directly above the placement position under the drive of the three-axis drive mechanism.

[0053] (2) After detecting the position of the chip to be placed through the vision detection mechanism, the direct-drive rotary platform is used to adjust its angle.

[0054] (3) Control the placement head assembly to move down rapidly to the pre-press position and then slowly press down. Use the displacement sensor to detect the displacement of the elastic member, and feedback the displacement signal to the controller for real-time monitoring. Stop moving until the detected displacement reaches the preset value, and perform pressure holding processing.

[0055] (4) Control the placement head assembly to release the chip and reset.

[0056] Among them, in step (3), the displacement sensor used is an eddy current sensor. When the displacement of the elastic member changes, the current signal of the eddy current sensor will also change accordingly. When processing this current signal, a second-order lag filter is used to smooth the step command current signal. The PI controller realizes the tracking of the filtered command current, and on this basis, an integral saturator is added to reduce the overshoot of the actual current, and a variable proportional gain control is added to reduce the current jitter during the pressure holding stage.

[0057] The specific implementation process is as follows:

[0058] The step command current is smoothed by a second-order lag filter, and the transfer function of the second-order lag filter is:

[0059] ;

[0060] where, is the time constant, is the damping ratio.

[0061] The inverse Laplace transform and time-domain discretization are performed on the transfer function to obtain the difference equation:

[0062] ;

[0063] is the discrete-time variable, , indicating the sampling time sequence number of the command current. When , the discrete-time variable in is negative, the initial values , are taken;

[0064] where, is the filtered command current, is the command current before filtering, , , , , .

[0065] The current error is defined as:

[0066] ;

[0067] where, is the actual current.

[0068] The current loop adopts PI control, and the output of the PI controller is:

[0069] ;

[0070] where, is the proportional gain coefficient, is the integral gain coefficient.

[0071] In PI control, the integrator accumulates the error amount to eliminate the steady-state error, but too large an integral term will cause overshoot. Therefore, an anti-windup integrator is introduced to reduce the overshoot:

[0072] ;

[0073] where, is output clipping, is the output after passing through the limiter, is the anti-saturation coefficient.

[0074] When the output saturates, the anti-saturation integrator can significantly weaken the integral accumulation. After the position error reverses, it quickly desaturates, achieving the effect of reducing the overshoot.

[0075] During the pressure-holding stage, the commanded current remains unchanged, but the actual current often has static jitter caused by noise. Excessive may cause amplification of high-frequency noise and exacerbate static jitter. Therefore, variable proportional gain control is introduced. When the current error reaches a certain range, is reduced, considering the case where the output of the PI controller is not saturated.

[0076] ;

[0077] and are the proportional gain coefficients at different stages ([[]] ), is the current error threshold for variable proportional gain control.

[0078] In summary, a pick-and-place head assembly for aligning the center of rotation based on direct drive technology according to the present invention drives the rotation of the pick-and-place head through a direct drive rotary platform, uses a displacement sensor to detect the deformation displacement of an elastic member connected to the pick-and-place head and feeds it back to the controller, and only sets a nozzle mounting seat and a nozzle assembly on the elastic member, minimizing the load pressure on the elastic member, thereby enabling more precise control of the pick-and-place pressure.

[0079] The above shows and describes the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments. The above embodiments and the descriptions in the specification only illustrate the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention will have various changes and improvements, and these changes and improvements all fall within the scope of the present invention claimed. The scope of protection claimed by the present invention is defined by the appended claims and their equivalents.

Claims

1. A pick-and-place head assembly for aligning the center of rotation based on direct drive technology, characterized in that: It includes a housing (10), a direct-drive rotary platform (20) is arranged inside the housing (10), and a force-controlled mounting head (30) is connected to the direct-drive rotary platform (20); The force-controlled mounting head (30) includes a first connecting block (31), a nozzle mounting seat (33) and at least one elastic member (32). Among them, The first connecting block (31) and the nozzle mounting seat (33) are connected to opposite ends of the elastic member (32); The first connecting block (31) is fixedly connected to the direct-drive rotary platform (20); A nozzle assembly (34) is arranged below the nozzle mounting seat (33), and an induction block (331) is arranged at a position where the nozzle mounting seat (33) protrudes from the elastic member (32). A displacement sensor (60) fixedly connected to the direct-drive rotary platform (20) is arranged directly above the induction block (331), and the displacement sensor (60) is electrically connected to the controller of the mounting force control system.

2. The mounting head assembly for aligning the center of rotation based on direct drive technology according to claim 1, characterized in that: The force-controlled mounting head (30) includes two elastic members (32) with the same shape, and the elastic members (32) are metal shrapnel. The first connecting block (31) and the nozzle mounting seat (33) are clamped between the two elastic members (32) with the same shape, and gaskets are arranged at the connection positions between the upper surface of the upper elastic member (32), the lower surface of the lower elastic member (32) and the first connecting block (31) and the nozzle mounting seat (33) for fixed connection.

3. The pick-and-place head assembly for aligning the center of rotation based on direct drive technology according to claim 1 or 2, characterized in that: A limit block (332) located on the nozzle mounting seat (33) is arranged below the induction block (331), and a support block (391) connected to the direct-drive rotary platform (20) and in contact with the limit block (332) is arranged directly below the limit block (332).

4. The pick-and-place head assembly for aligning the center of rotation based on direct drive technology according to claim 3, wherein: A second connecting block (37) is fixedly connected to the direct-drive rotary platform (20), a turntable (38) is fixedly connected to the second connecting block (37), a third connecting block (39) is arranged on the turntable (38), the support block (391) is arranged on the third connecting block (39), and the support block (391) can be adjusted up and down relative to the third connecting block (39).

5. The pick-and-place head assembly for aligning the center of rotation based on direct drive technology according to claim 1 or 2, characterized in that: The elastic member (32) is of a square frame structure. A through hole is arranged in the part of the nozzle mounting seat (33) located inside the square frame of the elastic member (32). The upper end of the through hole is sealed by a lens (36). A suction hole (341) paired with the through hole is arranged at the top of the nozzle assembly (34). A first vacuum suction hole communicated with the through hole is arranged on the nozzle mounting seat (33). A cover plate (50) connected to the housing (10) is arranged above the direct-drive rotary platform (20). The direct-drive rotary platform (20) is of a hollow annular structure, and an observation hole (51) corresponding to the position of the lens (36) is arranged on the cover plate (50).

6. The pick-and-place head assembly for aligning the center of rotation based on direct drive technology according to claim 5, wherein: The top of the nozzle assembly (34) is consistent with the shape and size of the bottom of the nozzle mounting base (33), and a cavity (342) is provided outside the suction hole (341). A second vacuum suction hole (333) that can communicate with the cavity (342) is provided at the bottom of the nozzle mounting base (33).

7. A pick-and-place head assembly for aligning the center of rotation based on direct drive technology according to claim 6, characterized in that: Adjusting bolts (21) for adjusting the levelness of the direct drive rotary platform (20) relative to the housing (10) are respectively provided at the diagonal corners of the direct drive rotary platform (20).

8. A pick-and-place head assembly for aligning a center of rotation based on a direct drive technology according to claim 1, characterized in that: The displacement sensor (60) is fixedly connected to the direct drive rotary platform (20) through a fourth connecting block (61), and a waist-shaped groove is provided on the connecting surface of the fourth connecting block (61).

9. The pick-and-place head assembly for aligning the center of rotation based on direct drive technology according to claim 1, characterized in that: An angular position feedback grating scale structure (40) for detecting the rotation angle of the direct drive rotary platform (20) is provided above the direct drive rotary platform (20).

Images