High-precision chip mounting device with double elastic members

Abstract

The application discloses a double-elastic-piece high-precision chip mounting device, which comprises a movable platform and a rotary driving mechanism capable of moving along the z-axis direction, and a suction mechanism arranged on one side of the movable platform; the rotary driving mechanism is used for driving the suction mechanism to rotate; the suction mechanism comprises a suction shaft, a nut and a suction nozzle sleeved at the bottom end of the suction shaft; the nut is rotationally connected to the movable platform outside the suction shaft, and the suction shaft can move along the z-axis in the nut; a force control mechanism for supporting and balancing the weight of the suction mechanism and a guide mechanism for supporting the rotation and movement of the suction shaft are mounted outside the suction mechanism. The application can reduce the acting force on the force control mechanism, so that the stiffness coefficient k of the spring can be relatively smaller, the spring deformation is larger under the premise of achieving the same mounting force, the control difficulty of the force control precision is reduced, the frictional resistance is smaller during mounting, the mounting force of the mounted chip can be more accurately controlled, and the mounting quality is improved.

Description

Technical Field

[0001] This application relates to the field of chip mounting technology, and in particular to a high-precision chip mounting device with dual elastic elements. Background Technology

[0002] During chip mounting, chips are often highly precise and fragile components. Therefore, it is crucial to strictly control the mounting pressure to avoid damaging the chip and ensure that the solder joints on the bottom of the chip make full contact with the pads on the substrate. This is essential for improving the reliability and stability of chip mounting. This is especially true in applications with extremely high chip quality requirements, such as the packaging of high-frequency, high-power devices, where strict control of the mounting pressure is necessary to protect the chip.

[0003] Different package types and chip sizes require different placement force. Generally, as chip size decreases, the force control requirements become more stringent. This is because smaller chips are more fragile and require more precise force control technology to ensure they are not damaged during placement. Excessive or insufficient placement force can lead to chip damage, warping, scratches, and other problems, thus affecting placement yield.

[0004] The existing patent technology, CN117936421A, discloses a high-precision mounting force control device and method based on dual elastic elements. This technology uses dual elastic elements to control the force of chip mounting. The rotation angle of the motor is determined by the number of pulses, which controls the change in distance between the adjustment plate and the mounting plate, thus obtaining the set mounting force. This is unaffected by the weight of the solder head and offers high control precision. However, both the solder head and the vision mechanism are located on the mounting plate, which undoubtedly greatly increases the gravity acting on the dual elastic elements, often requiring additional... For springs with a relatively large spring constant, when the spring... When the value is large, only a small deformation is needed to achieve the required mounting force. However, when mounting chips, it is difficult to accurately control the mounting force with a small amount of deformation, making it more difficult to control the chip mounting force precisely. Summary of the Invention

[0005] To address the aforementioned shortcomings, this application provides a high-precision chip mounting device with dual elastic elements, which can more easily control force precision, improve mounting accuracy and quality, and adopts the following technical solution:

[0006] A high-precision chip mounting device with dual elastic elements includes a movable platform, a rotary drive mechanism, and an adsorption mechanism. The movable platform can move along the z-axis, and the adsorption mechanism is located on one side of the movable platform for picking up and mounting chips.

[0007] The rotary drive mechanism is used to drive the adsorption mechanism to rotate;

[0008] The adsorption mechanism comprises an adsorption shaft, a screw cap, and a suction nozzle sleeved at the bottom end of the adsorption shaft for adsorbing the chip, the screw cap is rotationally connected to the movable platform outside the adsorption shaft, and the adsorption shaft can move along the z-axis in the screw cap;

[0009] The force control mechanism is arranged outside the adsorption mechanism and is used for supporting and balancing the weight of the adsorption mechanism.

[0010] The guide mechanism is sleeved outside the adsorption shaft and is used for supporting the rotation and movement of the adsorption shaft.

[0011] Preferably, the adsorption shaft comprises a rotating shaft and a guide shaft, the suction nozzle is detachably connected to the two ends of the rotating shaft, respectively, and the guide mechanism is sleeved outside the rotating shaft.

[0012] Preferably, the guide mechanism is an air bearing.

[0013] Preferably, the force control mechanism comprises a limiting part, an upper elastic member, and a lower elastic member, which are sequentially sleeved outside the guide shaft from top to bottom, and the movable platform is respectively provided with the upper elastic member and the lower elastic member between the limiting part and the rotating shaft.

[0014] Preferably, the displacement detection part is further arranged for detecting the displacement of the movable platform after the chip contacts the substrate.

[0015] Preferably, the movable platform is provided with a rotating part, and the rotating part is respectively provided with a connecting part abutting against the upper elastic member and the lower elastic member on both sides.

[0016] Preferably, the rotating drive mechanism comprises a power part and a synchronous transmission assembly, and the synchronous transmission assembly is connected to the driving end of the power part and the adsorption shaft, respectively.

[0017] Preferably, the outer wall of the adsorption shaft is provided with at least one guide groove extending along the axial direction of the adsorption shaft, and the screw cap is provided with a plurality of rolling bodies capable of circulating and rolling in the guide groove.

[0018] Preferably, the adsorption shaft is provided with an air channel, and the air channel is in communication with the suction nozzle.

[0019] Compared with the prior art, the application has the following beneficial effects:

[0020] The force control mechanism is sleeved outside the adsorption mechanism, the overall structure is compact, the occupied space is relatively smaller, and more space can be saved; only the gravity of the adsorption mechanism acts on the force control mechanism, so that the force control mechanism can adopt a stiffness coefficient The elastic member with a relatively small value can greatly reduce the control difficulty of force control precision and improve the force control precision by increasing the deformation of the elastic member, i.e. increasing the distance that the elastic member needs to be compressed, under the premise of obtaining the same mounting force.

[0021] Secondly, the guiding mechanism cooperates with the force control mechanism, which can greatly reduce the friction resistance of the adsorption shaft during mounting, make the adsorption mechanism mount the chip more flexibly, reduce the influence of the friction resistance on the force control precision, and further improve the force control precision of mounting. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 is a three-dimensional schematic view of the present application;

[0023] Figure 2 is a schematic view of the present application in a normal state;

[0024] Figure 3 is a schematic view of the present application when the chip contacts the substrate;

[0025] Figure 4 is a schematic view of the present application after the chip applies a mounting force.

[0026] In the figure:

[0027] 1, movable platform;

[0028] 2, adsorption mechanism, 21, adsorption shaft, 211, guiding shaft, 212, rotating shaft;

[0029] 3, force control mechanism, 31, upper elastic member, 32, lower elastic member;

[0030] 4, guiding mechanism, 5, rotating driving mechanism, 6, connecting part, 7, limiting part, 8, rotating part. DETAILED DESCRIPTION

[0031] The technical solutions in the embodiments of the present application will be described clearly and completely in combination with the drawings of the present application. Obviously, the embodiments described in the present application are only some of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all the other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0032] Reference is made to Figure 1 and Figure 4 for further detailed description of the present application:

[0033] The application discloses a high-precision chip mounting device with double elastic members, which comprises a movable platform 1, a rotating driving mechanism 5 and an adsorption mechanism 2, wherein the adsorption mechanism 2 is arranged on one side of the movable platform 1; the movable platform 1 can move along the z-axis to drive the adsorption mechanism 2 to mount a chip; wherein the movable platform 1 is driven by a longitudinal moving mechanism to move up and down along the z-axis direction, and the longitudinal moving mechanism can be arranged on the movable platform 1 on the side opposite to the adsorption mechanism 2, that is, on the side of the movable platform 1 away from the adsorption mechanism 2; the longitudinal moving mechanism can be a servo motor matched with a screw rod mechanism to realize the movement of the movable platform 1, which is not limited herein.

[0034] The adsorption mechanism 2 comprises an adsorption shaft 21, a screw cap and a suction nozzle, wherein the suction nozzle is arranged at the bottom end of the adsorption shaft 21 and used for picking up a chip; the screw cap is sleeved outside the adsorption shaft 21 and rotationally connected to the movable platform 1; and the adsorption shaft 21 can move along the z-axis direction in the screw cap; and the adsorption shaft 21 is internally provided with an air channel connected to the suction nozzle.

[0035] The rotating driving mechanism 5 is arranged on the movable platform 1 and used for driving the adsorption mechanism 2 to rotate, controlling the mounting angle of the chip and further improving the mounting precision of the chip.

[0036] The outer side of the adsorption mechanism 2 is further sleeved with a force control mechanism 3 and a guide mechanism 4; the guide mechanism 4 is arranged on the movable platform 1 and used for guiding the movement and rotation of the adsorption shaft 21; in the embodiment, the guide mechanism 4 can be an air bearing which can form an air film on the surface of the adsorption shaft 21 to reduce the frictional resistance when the adsorption shaft 21 moves or rotates; and the force control mechanism 3 is connected between the movable platform 1 and the adsorption mechanism 2 and used for supporting and balancing the weight of the adsorption mechanism 2 to reduce the influence of the gravity of the adsorption mechanism 2 on the mounting precision.

[0037] In combination Figure 2 , in the embodiment, the adsorption shaft 21 comprises a rotating shaft 212 and a guide shaft 211; the suction nozzle and the guide shaft 211 are respectively detachably connected to the two ends of the rotating shaft 212; and the guide mechanism 4 is sleeved outside the rotating shaft 212. The guide mechanism 4 is used for controlling the round runout of the rotating shaft 212 during rotation, thereby ensuring the mounting precision of the suction nozzle.

[0038] The force control mechanism 3 comprises a limiting part 7, an upper elastic member 31 and a lower elastic member 32 which are sequentially sleeved outside the guide shaft 211 from top to bottom; the two ends of the upper elastic member 31 are respectively abutted against the movable platform 1 and the limiting part 7; and the two ends of the lower elastic member 32 are respectively abutted against the movable platform 1 and the rotating shaft 212. In the embodiment, the upper elastic member 31 and the lower elastic member 32 are both springs; and the limiting part 7 can be a clamp.

[0039] Further comprising a displacement detection component for detecting the displacement amount of the movable platform 1 after the suction nozzle contacts the substrate. Wherein the displacement detection component can be a displacement sensor, the displacement detection component can be arranged on the longitudinal movement mechanism, the movable platform 1 side is horizontally mounted with a baffle, and the end of the displacement sensor abuts the bottom of the baffle. The position of the displacement sensor on the longitudinal movement mechanism is adjusted when the suction nozzle contacts the substrate, and the end of the displacement sensor abuts the bottom of the baffle on the side of the movable platform 1 when the suction nozzle contacts the substrate. When the suction nozzle contacts the substrate, the end of the displacement detection component abuts the movable platform 1, thereby detecting the displacement amount of the movable platform 1. Of course, the photoelectric sensor in CN117936421A can also be used.

[0040] According to Hooke's law , wherein, is the stiffness coefficient, is the spring deformation amount.

[0041] The force applied on the elastic member in the prior art (such as the weight of the welding head, the visual mechanism) is large, in order to achieve the balance effect, a spring with a large stiffness coefficient value is needed; when the mounting force to be applied is certain, the larger the stiffness coefficient value is, the smaller the deformation amount is, and the resolution (motor control accuracy) of the motor is difficult to improve, and it is difficult to achieve accurate control of the mounting force through a small range of deformation amount , therefore, it is more difficult to control the force control accuracy, and the resolution requirement of the motor is higher.

[0042] In combination with Figure 4 , the upper elastic member 31 and the lower elastic member 32 are both in a compressed state; assuming that the initial compression amount of the upper elastic member 31 is , the initial compression amount of the lower elastic member 32 is , and the displacement detection component detects the displacement amount of the movable platform 1 after the chip contacts the substrate .

[0043] In combination with Figure 2 , under static state, the suction mechanism 2 and the limiting component 7 thereon are taken as the force analysis object, under the influence of gravity, the weight of each component acts on the force control mechanism 3, at this time, the chip sucked by the suction nozzle is not in contact with the substrate, and the lower elastic member 32 on one side is balanced with the lower elastic member 32 on the other side, that is, ; the left side of the equation is the force direction upward, the right side of the equation is the force direction downward. Wherein, Only the total weight of the suction mechanism 2 and the limiting component 7, so the gravity acting on the force control mechanism 3 is small.

[0044] In combination Figure 3 When the suction nozzle abuts against the surface of the substrate, at this time, the suction mechanism 2 is in a static state, and the end of the displacement sensor abuts against the movable platform 1 synchronously.

[0045] In combination Figure 4 In the working state, the movable platform 1 continues to move downward to exert the mounting force on the chip, in this process, the compression amount of the upper elastic member 31 continuously decreases, that is, the length of the upper elastic member 31 becomes longer; the compression amount of the lower elastic member 32 continuously increases, that is, the length of the lower elastic member 32 becomes shorter; the mounting force exerted on the chip also continuously increases, when the movable platform 1 moves , the downward mounting force exerted on the chip reaches the preset mounting force , the suction shaft 21 will be subjected to the reaction force equal in size and opposite in direction to the mounting force At this time, the compression amount of the upper elastic member 31 is , the compression amount of the lower elastic member 32 is That is, Finally, it can be deduced that That is, the displacement detection component detects that the displacement amount of the movable platform 1 and the mounting force are in a linear relationship.

[0046] Wherein, in the process of exerting the mounting force on the chip, the displacement amount of the movable platform 1 is always less than the initial compression amount of the upper elastic member 31. Under the same mounting force requirement, if the prior art adopts a spring with a smaller K value, the spring is more likely to be compressed, and the larger gravity may cause the upper spring to be compressed together in the initial state, and it is difficult to balance the weight of the suction mechanism 2.

[0047] The force control mechanism 3 of the present application only needs to balance the gravity of the suction mechanism 2, so a spring with a relatively small stiffness coefficient value can be adopted, at this time, the deformation amount of the spring will also increase accordingly, under the same mounting force, compared with the prior art, the present application can provide more accurate mounting force to the chip by increasing the spring deformation amount , and the overall structure is more compact, and the occupied space is relatively small, under the premise of the same resolution motor, the mounting force control is more accurate.

[0048] In order to avoid the torsion of the upper elastic member 31 and the lower elastic member 32 when the adsorption mechanism 2 rotates, affecting the force control accuracy, a rotating component 8 is arranged in the movable platform 1, and the two sides of the rotating component 8 are respectively provided with a connecting component 6 abutting against the upper elastic member 31 and the lower elastic member 32. The connecting component 6 can be a gasket, and the rotating component 8 can be a bearing. The outer ring of the rotating component 8 is connected to the movable platform 1, and the connecting component 6 abuts against the inner ring of the rotating component 8. The upper elastic member 31 and the lower elastic member 32 both abut against the connecting component 6. When the adsorption mechanism 2 rotates, the upper elastic member 31 and the lower elastic member 32 can rotate with the adsorption mechanism 2, thereby avoiding torsion.

[0049] The adsorption shaft 21 is provided with a gap between the rotating component 8 and the connecting component 6, that is, the adsorption shaft 21 does not contact the rotating component 8 and the connecting component 6 during rotation or movement, so as to reduce the frictional resistance.

[0050] The rotating driving mechanism 5 includes a power component and a synchronous transmission assembly. The power component can be a motor, and the synchronous transmission assembly is connected to the driving end of the power component and the guide shaft 211 respectively. The synchronous transmission assembly is a belt wheel transmission. The driving end of the power component and the screw cap are both provided with a belt wheel, and are connected through a transmission belt. The belt wheel is sleeved on the outside of the screw cap. The movable platform 1 is also provided with a tensioning component, which can tension the synchronous driving assembly.

[0051] The outer side wall of the guide shaft 211 is provided with at least one guide groove extending in the axial direction of the guide shaft 211. The screw cap is provided with a plurality of rolling bodies capable of rolling in the guide groove. The guide shaft 211 is supported and guided in the screw cap by the rolling bodies during movement. Compared with the face-to-face contact sliding between the guide rail and the sliding block in the prior art, the frictional resistance of the present application is smaller, thereby further reducing the influence of the frictional resistance of the guide shaft 211 during movement on the force control accuracy during mounting, and further improving the mounting accuracy. In the embodiment, the guide shaft 211, the rolling bodies and the screw cap can be a ball guide shaft structure.

[0052] In some embodiments, an adapter component is arranged on the end of the adsorption shaft away from the suction nozzle, for connecting a vacuum generating device.

Claims

1. A high-precision chip mounting device with dual elastic elements, characterized in that: The device comprises a movable platform, a rotating driving mechanism and an adsorption mechanism, the movable platform is movable along the z-axis direction, the adsorption mechanism is arranged on one side of the movable platform and used for sucking and mounting a chip; the rotating driving mechanism is used for driving the adsorption mechanism to rotate, and the rotating driving mechanism is arranged on the movable platform; the adsorption mechanism comprises an adsorption shaft, a screw cap and a suction nozzle arranged on the bottom end of the adsorption shaft and used for adsorbing a chip, the screw cap is arranged outside the adsorption shaft and is rotationally connected with the movable platform, and the adsorption shaft is movable along the z-axis direction in the screw cap; a force control mechanism is arranged outside the adsorption mechanism and used for supporting and balancing the weight of the adsorption mechanism; a guide mechanism is arranged outside the adsorption shaft and used for supporting the rotation and movement of the adsorption shaft; the adsorption shaft comprises a rotating shaft and a guide shaft, the suction nozzle is detachably connected with the guide shaft at two ends of the rotating shaft, and the guide mechanism is arranged outside the rotating shaft; the force control mechanism comprises a limiting part, an upper elastic member and a lower elastic member which are arranged outside the guide shaft in sequence from top to bottom, and the movable platform is respectively provided with the upper elastic member and the lower elastic member corresponding to the limiting part and the rotating shaft.

2. The dual-elastic member high-precision chip mounting apparatus according to claim 1, characterized by: The guide mechanism is an air bearing.

3. The dual-elastic member high-precision chip mounting device according to claim 1, characterized in that: A displacement detection part is further arranged and used for detecting the displacement of the movable platform after the chip contacts a substrate.

4. The dual-elastic member high-precision chip mounting apparatus according to claim 1, characterized by: A rotating part is arranged in the movable platform, and the rotating part is respectively provided with a connecting part abutting against the upper elastic member and the lower elastic member on two sides of the rotating part.

5. The dual-elastic member high-precision chip mounting apparatus according to claim 1, characterized by: The rotating driving mechanism comprises a power part and a synchronous transmission assembly, and the synchronous transmission assembly is connected with the driving end of the power part and the adsorption shaft.

6. The dual-elastic piece high-precision chip mounting device according to claim 1, characterized in that: At least one guide groove is arranged on the outer wall of the adsorption shaft and extends along the axial direction of the adsorption shaft, and a plurality of rolling bodies are arranged in the screw cap and can roll in the guide groove.

7. The dual-elastic piece high-precision chip mounting device according to claim 1, characterized in that: An air channel is arranged in the adsorption shaft and communicates with the suction nozzle.

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