Pressure-controllable chip mounting head

Abstract

The present invention provides a pressure-controllable chip mounting head, comprising a vertical drive assembly, a first-stage sliding assembly, and a second-stage sliding assembly. The first-stage sliding assembly comprises a first-stage sliding table, and the second-stage sliding assembly comprises a second-stage sliding table. A hollow rotating shaft is rotatably installed within the second-stage sliding table, and a suction head is fixed at the bottom of the hollow rotating shaft. A spring assembly is installed between the first-stage sliding table and the second-stage sliding table. A grating scale is fixed on the first-stage sliding table, and a read head is fixed on the second-stage sliding table at a position corresponding to the grating scale. The spring assembly comprises an extension spring and an adjustment spring assembly. The extension spring is connected to the first-stage sliding table and the second-stage sliding table, such that the second-stage sliding table is suspended below the first-stage sliding table. The adjustment spring assembly comprises a spring guide post, the top of the spring guide post being fixed to the first-stage sliding table, and the bottom of the spring guide post being slidably inserted into the second-stage sliding table. A large spring and a small spring are sleeved on the spring guide post. The present invention facilitates reduced difficulty and a low technical threshold for pressure control, and the chip mounting head has a compact overall structure and low cost.

Description

A pressure-controlled chip mounting head Technical Field

[0001] This invention relates to the field of chip mounting technology, and in particular to a pressure-controlled chip mounting head. Background Technology

[0002] In recent years, the semiconductor industry has flourished, leading to a surge in demand for related chip packaging technologies. Taking eutectic bonding machines, die bonders, and sintering machines as examples, they all share the common characteristic of requiring different pressures during chip mounting to achieve the desired process. In particular, chip mounting related to SiC chips requires even more precise control over pressure, which has resulted in the development of many chip mounting heads that control the pressure applied to pick up and mount chips.

[0003] There are two main types of existing chip mounting heads:

[0004] One type of chip placement head uses a multi-motor approach to control the force applied to pick up and place the chip. Typically, it uses two motors to control the large and small forces respectively. This technique forces the chip placement head to have an excessively large overall structure, shortened stroke, and increased cost, which is detrimental to the current demand for miniaturization and cost reduction in various placement equipment.

[0005] Another type of chip placement head uses strain gauges or pressure sensors to control pressure. However, due to the limitations of the strain gauge material, the pressure range that this type of chip placement head can control is very limited. Generally, multiple sensors or strain gauges with different ranges need to be used simultaneously to separately control excessively high or low pressures.

[0006] Existing chip mounting heads have an excessively large overall structure and high cost, and face challenges such as high pressure control difficulty and high technical barriers. Summary of the Invention

[0007] This invention proposes a pressure-controllable chip mounting head to solve the technical problems of existing chip mounting heads, such as excessively large overall structure, high cost, high difficulty in pressure control, and high technical threshold.

[0008] One aspect of the present invention is to provide a pressure-controllable chip mounting head, the chip mounting head including at least a fixed mounting base, a vertical drive assembly, a primary sliding assembly, and a secondary sliding assembly;

[0009] The vertical drive assembly is mounted on the fixed mounting base; the primary sliding assembly includes at least one primary slide table.

[0010] The vertical drive component is connected to the first-stage slide of the first-stage sliding component and is used to drive the first-stage slide to reciprocate in the vertical direction.

[0011] The secondary sliding assembly includes at least a secondary slide table; a hollow rotating shaft is rotatably mounted inside the secondary slide table in the vertical direction, and a suction head is fixed at the bottom of the hollow rotating shaft;

[0012] A spring assembly is installed between the primary slide and the secondary slide; a grating ruler is fixed on the primary slide, and a reading head is fixed on the secondary slide corresponding to the position of the grating ruler.

[0013] The spring assembly includes a tension spring, one end of which is fixed to the primary slide and the other end of which is fixed to the secondary slide, so that the secondary slide is suspended below the primary slide and that the secondary slide moves freely in the vertical direction relative to the primary slide.

[0014] The spring assembly further includes an adjusting spring assembly, which includes a spring guide post. The top of the spring guide post is fixed to the primary slide, and the bottom of the spring guide post is slidably inserted into the secondary slide.

[0015] Specifically, a limiting nut and a limiting sleeve are fixed on the spring guide post, with the limiting sleeve located below the limiting nut; a large spring is sleeved on the spring guide post, and the large spring is located between the limiting nut and the limiting sleeve;

[0016] A small spring is fitted onto the spring guide post, and the small spring is located between the limiting sleeve and the secondary slide.

[0017] In a preferred embodiment, the vertical drive assembly includes a first motor, a ball screw shaft, and a ball screw seat;

[0018] The first motor is fixed on the fixed mounting base, and the ball screw shaft is connected to the output shaft of the first motor; the ball screw seat is fixed to the first-stage slide, and the ball screw shaft is installed in the ball screw seat and passes through the first-stage slide;

[0019] When the first motor drives the ball screw shaft to rotate, the ball screw shaft drives the ball screw seat to reciprocate in the vertical direction, thereby driving the first-stage slide to reciprocate in the vertical direction.

[0020] In a preferred embodiment, the vertical drive assembly further includes a first motor mounting base, the first motor being fixed to the first motor mounting base, and the first motor mounting base being fixed to the fixed mounting base.

[0021] In a preferred embodiment, the output shaft of the first motor is connected to the ball screw shaft via a first coupling.

[0022] In a preferred embodiment, the primary sliding assembly further includes a slide rail and a slider;

[0023] The slider is fixed to the primary slide table, the slide rail is fixed to the fixed mounting base, and the slider is slidably connected to the slide rail;

[0024] When the primary slide table reciprocates in the vertical direction, the slider reciprocates along the slide rail.

[0025] In a preferred embodiment, a cross roller guide is installed between the primary slide and the secondary slide.

[0026] In a preferred embodiment, the chip mounting head further includes a rotation drive assembly;

[0027] The rotary drive assembly includes a second motor, a hollow ball spline shaft, and a ball spline seat;

[0028] The second motor is fixed to the fixed mounting base, and the ball spline seat is rotatably mounted in the fixed mounting base; the second motor is used to drive the ball spline seat to rotate.

[0029] The hollow ball spline shaft is installed in the ball spline seat. The hollow ball spline shaft is configured to reciprocate in the vertical direction relative to the ball spline seat, and to drive the hollow ball spline shaft to rotate when the ball spline seat rotates.

[0030] The hollow ball spline shaft passes through the fixed mounting base and the first-stage slide, and is connected to the hollow rotating shaft;

[0031] When the ball spline seat rotates, it drives the hollow ball spline shaft to rotate, which in turn drives the hollow rotating shaft and the suction head to rotate.

[0032] In a preferred embodiment, the outer surface of the hollow ball spline shaft is provided with a first ball groove extending in a vertical direction, and the inner surface of the ball spline seat is provided with a second ball groove extending in a vertical direction.

[0033] Balls are installed in the first ball groove and the second ball groove, so that the hollow ball spline shaft reciprocates in the vertical direction relative to the ball spline seat, and the hollow ball spline shaft rotates when the ball spline seat rotates.

[0034] In a preferred embodiment, the rotary drive assembly further includes a second motor mounting base, the second motor being fixed to the second motor mounting base, and the second motor mounting base being fixed to the fixed mounting base;

[0035] The output shaft of the second motor is connected to the first pulley, and the ball spline seat fixes the second pulley; a belt is arranged around the first pulley and the second pulley;

[0036] When the second motor drives the first pulley to rotate, the second pulley drives the ball spline seat to rotate.

[0037] In a preferred embodiment, an air extraction port is installed on the top of the hollow ball spline shaft;

[0038] The bottom of the hollow ball spline shaft is connected to the hollow rotating shaft via a second coupling.

[0039] Compared with the prior art, the present invention has the following beneficial effects:

[0040] The present invention proposes a pressure-controllable chip mounting head, which fixes a grating ruler on a primary slide, fixes a reading head on a secondary slide at the position corresponding to the grating ruler, and installs a spring assembly between the primary and secondary slides. The reading head reads the elongation of the tension spring and the compression of the large and small springs to obtain the pressure of the pick-up head on the chip, thereby controlling the pressure on the chip.

[0041] The present invention proposes a pressure-controllable chip mounting head, which has low pressure control difficulty and low technical threshold, small overall structure and low cost, and more convenient chip mounting head wiring. Attached Figure Description

[0042] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the accompanying drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without any creative effort.

[0043] Figure 1 is a perspective view of a pressure-controllable chip mounting head according to the present invention.

[0044] Figure 2 is a front view of a pressure-controllable chip mounting head according to the present invention.

[0045] Figure 3 is a perspective view of the interconnection of the primary sliding component, the secondary sliding component, and the spring component of the present invention.

[0046] Figure 4 is a front view of the interconnection of the primary sliding component, the secondary sliding component, and the spring component of the present invention.

[0047] Figure 5 is a side view (viewed from right to left in Figure 4) showing the interconnection of the first-stage sliding component, the second-stage sliding component, and the spring component of the present invention.

[0048] Figure 6 is a schematic diagram of the adjusting spring assembly of the present invention.

[0049] Figure 7 is a cross-sectional view along the AA direction in Figure 6.

[0050] Figure 8 is a schematic diagram of the hollow ball spline shaft of the present invention installed in the ball spline seat.

[0051] Figure 9 is a cross-sectional view along the BB direction in Figure 8. Detailed Implementation

[0052] To make the above and other features and advantages of the present invention clearer, the invention will be further described below with reference to the accompanying drawings. It should be understood that the specific embodiments given herein are for the purpose of explanation to those skilled in the art and are exemplary only, not restrictive.

[0053] Referring to Figures 1 to 9, according to an embodiment of the present invention, a pressure-controllable chip mounting head is provided. The chip mounting head includes a mounting adapter plate 1, a fixed mounting base 2, a vertical drive assembly 3, a primary sliding assembly 4, a secondary sliding assembly 5, a spring assembly 6, a rotary drive assembly 7, and a suction head 8.

[0054] The mounting adapter plate 1 is fixed to the machine base (not shown in the figure), and the fixed mounting base 2 is fixed to the mounting adapter plate 1, thereby fixing the fixed mounting base 2 to the machine base.

[0055] Referring to Figures 1 and 2, according to an embodiment of the present invention, the vertical drive assembly 3 is mounted on the fixed mounting base 2. Specifically, the vertical drive assembly 3 includes a first motor mounting base 301, a first motor 302, a ball screw shaft 303, a ball screw seat 304, and a first coupling 305.

[0056] The first motor 302 is fixed on the fixed mounting base 2, and the ball screw shaft 303 is connected to the output shaft of the first motor 302. Specifically, the first motor 302 is fixed on the first motor mounting base 301, and the first motor mounting base 301 is fixed on the fixed mounting base 2, thereby fixing the first motor 302 to the fixed mounting base 2. The output shaft of the first motor 302 is connected to the ball screw shaft 303 through the first coupling 305, thereby connecting the ball screw shaft 303 to the output shaft of the first motor 302.

[0057] The ball screw shaft 303 is installed inside the ball screw seat 304. When the first motor 302 drives the ball screw shaft 303 to rotate, the ball screw shaft 303 drives the ball screw seat 304 to reciprocate in the vertical direction.

[0058] Referring to Figures 1 and 2, according to an embodiment of the present invention, the primary sliding assembly 4 includes a primary slide table 401, a slide rail 402, a slider 403, and a grating ruler 404.

[0059] The vertical drive component 3 is connected to the first-stage slide 401 of the first-stage sliding component 4, and is used to drive the first-stage slide 401 to reciprocate in the vertical direction.

[0060] Specifically, the ball screw seat 304 of the vertical drive assembly 3 is fixed to the first-stage slide 401, and the ball screw shaft 303 is installed inside the ball screw seat 304 and passes through the first-stage slide 401.

[0061] When the first motor 302 drives the ball screw shaft 303 to rotate, the ball screw shaft 303 drives the ball screw seat 304 to reciprocate in the vertical direction, thereby driving the first-stage slide table 401 to reciprocate in the vertical direction.

[0062] The slider 403 is fixed to the primary slide table 401, and the slide rail 402 is fixed to the fixed mounting base 2. The slider 403 is slidably connected to the slide rail 402. When the primary slide table 401 reciprocates in the vertical direction, the slider 403 reciprocates along the slide rail 402.

[0063] A grating ruler 404 is fixed on the primary slide 401. When the primary slide 401 reciprocates in the vertical direction, the grating ruler 404 reciprocates synchronously in the vertical direction with the primary slide 401.

[0064] Referring to Figures 1 and 2, according to an embodiment of the present invention, the secondary sliding assembly 5 includes a secondary slide table 501, a cross roller guide 502, a reading head 503, and a hollow rotating shaft 504.

[0065] A cross roller guide 502 is installed between the primary slide 401 and the secondary slide 501. A hollow rotating shaft 504 is installed vertically inside the secondary slide 501 in a rotatable manner, and a suction head 8 is fixed to the bottom of the hollow rotating shaft 504.

[0066] Install a spring assembly 6 between the primary slide 401 and the secondary slide 501. Fix a grating ruler 404 on the primary slide 401, and fix a reading head 503 on the secondary slide 501 at the position corresponding to the grating ruler 404.

[0067] Referring to Figures 3, 4 and 5, according to an embodiment of the present invention, the spring assembly 6 includes a tension spring 601 and an adjusting spring assembly 602.

[0068] One end of the tension spring 601 is fixed to the primary slide 401, and the other end of the tension spring 601 is fixed to the secondary slide 501, so that the secondary slide 501 is suspended below the primary slide 401 and the secondary slide 501 moves freely in the vertical direction relative to the primary slide 401.

[0069] Specifically, tension spring posts 603 are fixed to both ends of tension spring 601. The tension spring posts 603 at both ends of tension spring 601 are fixed to the primary slide 401 and the secondary slide 501 respectively, thereby suspending the secondary slide 501 below the primary slide 401. With tension spring 601 suspending the secondary slide 501 below the primary slide 401, tension spring 601 is in a stretched state.

[0070] As shown in Figure 5, in this embodiment, two tension springs 601 are provided, so that the secondary slide 501 is stably suspended below the primary slide 401. The number of tension springs 601 is not specifically limited; there can be one or more tension springs, depending on actual needs.

[0071] Referring to Figures 3, 4, 5, 6 and 7, according to an embodiment of the present invention, the adjusting spring assembly 602 includes a spring guide post 6021, the top of which is fixed to the primary slide 401, and the bottom of which is slidably inserted into the secondary slide 501.

[0072] A limiting nut 6025 and a limiting sleeve 6023 are fixed on the spring guide post 6021, with the limiting sleeve 6023 located below the limiting nut 6025. A large spring 6022 is fitted onto the spring guide post 6021, and the large spring 6022 is located between the limiting nut 6025 and the limiting sleeve 6023.

[0073] A small spring 6024 is fitted onto the spring guide post 6021, and the small spring 6022 is located between the limiting sleeve 6023 and the secondary slide 501 (the upper surface of the secondary slide 501).

[0074] When the tension spring 601 suspends the secondary slide 501 below the primary slide 401, the tension spring 601 is in a stretched state, the large spring 6022 is in an initial state between the limiting nut 6025 and the limiting sleeve 6023 (the large spring 6022 is neither stretched nor compressed), and the small spring 6024 is in an initial state between the limiting sleeve 6023 and the secondary slide 501 (the small spring 6024 is neither stretched nor compressed).

[0075] Referring to Figures 1, 2, 8 and 9, according to an embodiment of the present invention, the rotary drive assembly 7 includes a second motor mounting base 701, a second motor 702, a hollow ball spline shaft 703, a first pulley 704, a belt 705, a second pulley 706, a ball spline seat 707 and a second coupling 708.

[0076] The second motor 702 is fixed on the fixed mounting base 2, and the ball spline seat 707 is rotatably mounted in the fixed mounting base 2. The second motor 702 is used to drive the ball spline seat 707 to rotate.

[0077] Specifically, the second motor 702 is fixed on the second motor mounting base 701, and the second motor mounting base 701 is fixed on the fixed mounting base 2, thereby fixing the second motor 702 on the fixed mounting base 2.

[0078] The output shaft of the second motor 702 is connected to the first belt pulley 704, the ball spline seat 707 fixes the second pulley 706, and the belt 705 is arranged around the first pulley 704 and the second pulley 706.

[0079] When the second motor 702 drives the first pulley 704 to rotate, the belt 705 drives the second pulley 706 to rotate, and the second pulley 706 drives the ball spline seat 707 to rotate.

[0080] As shown in Figures 8 and 9, the hollow ball spline shaft 703 is mounted inside the ball spline holder 707, which is rotatably mounted in the fixed mounting base 2. The hollow ball spline shaft 703 is configured to reciprocate vertically relative to the ball spline holder 707, and the rotation of the ball spline holder 707 drives the hollow ball spline shaft 703 to rotate.

[0081] Specifically, the outer surface of the hollow ball spline shaft 703 is provided with a first ball groove 7031 extending in the vertical direction, and the inner surface of the ball spline seat 707 is provided with a second ball groove 7071 extending in the vertical direction.

[0082] Balls 7072 are installed in the first ball groove 7031 and the second ball groove 7071, so that the hollow ball spline shaft 703 reciprocates in the vertical direction relative to the ball spline seat 707, and the hollow ball spline shaft 703 rotates when the ball spline seat 707 rotates.

[0083] Returning to Figures 1 and 2, the hollow ball spline shaft 703 passes through the fixed mounting base 2 and the first-stage slide 701, and is connected to the hollow rotating shaft 504.

[0084] When the ball spline seat 707 rotates, it drives the hollow ball spline shaft 703 to rotate, which in turn drives the hollow rotating shaft 705 and the suction head 8 to rotate, thereby adjusting the angle of the suction head 8.

[0085] Furthermore, a vacuum port 704 is installed on the top of the hollow ball spline shaft 703 for connecting to a vacuum generator. The vacuum generator draws a vacuum, which is then applied to the suction head 8 through the hollow channels inside the hollow ball spline shaft 703 and the hollow rotating shaft 504, thereby allowing the suction head 8 to adsorb the chip.

[0086] Furthermore, the bottom of the hollow ball spline shaft 703 is connected to the hollow rotating shaft 504 via a second coupling 708.

[0087] The chip picking and chip mounting process of a pressure-controllable chip mounting head according to the present invention will be described below with reference to Figures 1 to 9.

[0088] Chip pickup.

[0089] When picking up a chip, the first motor 302 drives the ball screw shaft 303 to rotate, and the ball screw shaft 303 drives the ball screw seat 304 to move downward in the vertical direction, thereby driving the first-stage slide 401 to move downward in the vertical direction. The slider 403 moves downward along the slide rail 402 to guide the first-stage slide 401.

[0090] During the downward vertical movement of the primary slide 401, the primary slide 401 drives the spring guide post 6021 to move downward vertically as well. The spring guide post 6021 transmits force to the limiting nut 6025, the limiting nut 6025 transmits force to the large spring 6022, the large spring 6022 transmits force to the limiting sleeve 6023, the limiting sleeve 6023 transmits force to the small spring 6024, and the small spring 6024 transmits force to the secondary slide 501. Thus, the secondary slide 501 moves downward vertically under the influence of the primary slide 401. During this process, the slight up-and-down sliding of the secondary slide 501 relative to the primary slide 401 is guided by the crossed roller guide rail 502.

[0091] As the secondary slide 501 moves vertically downward under the drive of the primary slide 401, it simultaneously drives the suction head 8, hollow rotating shaft 504, second coupling 708, hollow ball spline shaft 703, and air extraction port 704 to move vertically downward. During the downward vertical movement of the hollow ball spline shaft 703, relative motion occurs between it and the ball spline seat 707.

[0092] When the suction head 8 contacts the chip, the secondary slide 501 stops moving downward in the vertical direction. At this time, the tension spring 601 is in the tension state, the large spring 6022 is in the initial state (the large spring 6022 is neither stretched nor compressed), and the small spring 6024 is in the initial state (the small spring 6024 is neither stretched nor compressed).

[0093] At this time, the tension spring 601 is in a stretched state, suspending the secondary slide 501 below the primary slide 401. The tension of the tension spring 601 counteracts the overall weight of the suction head 8, hollow rotating shaft 504, secondary slide 501, second coupling 708, hollow ball spline shaft 703 and air extraction port 704, so the chip is not subjected to force (does not bear the pressure of the suction head 8).

[0094] The primary slide 401 continues to move downward in the vertical direction. Since the suction head 8 is in contact with the chip, the secondary slide 501 cannot continue to move downward in the vertical direction. The primary slide 401 and the secondary slide 501 generate relative movement. During this process, the relative movement of the primary slide 401 and the secondary slide 501 is guided by the cross roller guide 502.

[0095] As the first-stage slide 401 continues to move downwards in the vertical direction, the tension spring 601 shortens, and the spring guide post 6021 transmits the force to the limit nut 6025, the limit nut 6025 transmits the force to the large spring 6022, the large spring 6022 transmits the force to the limit sleeve 6023, and the limit sleeve 6023 transmits the force to the small spring 6024.

[0096] Since the elastic coefficient of the small spring 6024 is much smaller than that of the large spring 6022, the small spring 6024, located between the limiting sleeve 6023 and the secondary slide 501 (the upper surface of the secondary slide 501), is the first to compress.

[0097] The reading head 503 reads the reading of the grating ruler 404 and calculates the relative displacement between the first-stage slide 401 and the second-stage slide 501, which is the compression of the small spring 6024. At this time, the shortening of the tension spring 601 is equal to the compression of the small spring 6024.

[0098] The compressive force N1 of the small spring 6024 and the tensile force N2 of the tension spring 601 were calculated using Hooke's Law. Finally, the pressure N exerted by the suction head 8 on the chip was calculated using the following method:

[0099] The suction head 8 exerts pressure N on the chip, which is equal to the pressure N1 of the small spring 6024 plus the gravity G minus the tension N2 of the tension spring 601.

[0100] The gravity G is the total gravity of the suction head 8, hollow rotating shaft 504, secondary slide 501, second coupling 708, hollow ball spline shaft 703 and air extraction port 704.

[0101] When the pressure N generated by the suction head 8 on the chip reaches a certain value, the vacuum generator evacuates the suction port 704, and evacuates the suction head 8 through the hollow ball spline shaft 703 and the hollow rotating shaft 504, thereby causing the suction head 8 to adsorb the chip.

[0102] Chip mounting.

[0103] After the suction head 8 picks up the chip, the first motor 302 drives the ball screw shaft 303 to rotate. The ball screw shaft 303 drives the ball screw seat 304 to move upward in the vertical direction, thereby driving the first-stage slide 401 to move upward in the vertical direction.

[0104] During the upward movement of the primary slide 401 in the vertical direction, the primary slide 401 drives the secondary slide 501 to move upward in the vertical direction through the tension spring 601.

[0105] As the secondary slide 501 moves vertically upward under the drive of the primary slide 401, it drives the suction head 8, hollow rotating shaft 504, second coupling 708, hollow ball spline shaft 703 and air extraction port 704 to move vertically upward simultaneously, causing the chip to leave the working surface where the chip is placed.

[0106] The chip placement head is transferred to the working surface of chip placement. The second motor 702 drives the first pulley 704 to rotate, the belt 705 drives the second pulley 706 to rotate, and the second pulley 706 drives the ball spline seat 707 to rotate.

[0107] The rotation of the ball spline seat 707 drives the hollow ball spline shaft 703 to rotate, which in turn drives the hollow rotating shaft 705 and the suction head 8 to rotate, thereby adjusting the angle of the suction head 8 and the angle at which the suction head 8 picks up the chip.

[0108] The first motor 302 drives the ball screw shaft 303 to rotate, and the ball screw shaft 303 drives the ball screw seat 304 to move downward in the vertical direction, thereby driving the first-stage slide 401 to move downward in the vertical direction.

[0109] During the downward vertical movement of the primary slide 401, the primary slide 401 drives the spring guide post 6021 to move downward vertically. The spring guide post 6021 transmits force to the limit nut 6025, the limit nut 6025 transmits force to the large spring 6022, the large spring 6022 transmits force to the limit sleeve 6023, the limit sleeve 6023 transmits force to the small spring 6024, and the small spring 6024 transmits force to the secondary slide 501, thereby causing the secondary slide 501 to move downward vertically under the drive of the primary slide 401.

[0110] As the secondary slide 501 moves vertically downward under the drive of the primary slide 401, it drives the suction head 8, hollow rotating shaft 504, second coupling 708, hollow ball spline shaft 703 and air extraction port 704 to move vertically downward simultaneously.

[0111] When the chip adsorbed by the suction head 8 comes into contact with the product to be mounted (e.g., PCB board), the secondary slide 501 stops moving downward in the vertical direction. At this time, the tension spring 601 is in the tension state, the large spring 6022 is in the initial state (the large spring 6022 is neither stretched nor compressed), and the small spring 6024 is in the initial state (the small spring 6024 is neither stretched nor compressed).

[0112] At this time, the tension spring 601 is in a stretched state, suspending the secondary slide 501 below the primary slide 401. The tension of the tension spring 601 counteracts the overall weight of the suction head 8, hollow rotating shaft 504, secondary slide 501, second coupling 708, hollow ball spline shaft 703 and air extraction port 704, so the chip adsorbed by the suction head 8 does not put pressure on the product to be mounted (such as PCB board).

[0113] As the primary slide 401 continues to move downwards in the vertical direction, the secondary slide 501 cannot continue to move downwards in the vertical direction because the chip adsorbed by the suction head 8 is in contact with the product to be mounted (such as a PCB board). The primary slide 401 and the secondary slide 501 then move relative to each other.

[0114] As the primary slide 401 continues to move downwards in the vertical direction, the tension spring 601 shortens. The spring guide post 6021 transmits the force to the limit nut 6025, the limit nut 6025 transmits the force to the large spring 6022, the large spring 6022 transmits the force to the limit sleeve 6023, and the limit sleeve 6023 transmits the force to the small spring 6024. The small spring 6024, located between the limit sleeve 6023 and the secondary slide 501 (the upper surface of the secondary slide 501), is the first to begin to compress.

[0115] Since the elastic coefficient of the small spring 6024 is much smaller than that of the large spring 6022, the small spring 6024, located between the limiting sleeve 6023 and the secondary slide 501 (the upper surface of the secondary slide 501), is the first to compress.

[0116] When the compression of the small spring 6024 reaches its limit (the small spring 6024 stops compressing), the large spring 6022, located between the limit nut 6025 and the limit sleeve 6023, begins to compress.

[0117] The reading head 503 reads the reading of the grating ruler 404 and calculates the relative displacement between the first-stage slide 401 and the second-stage slide 501, which is the maximum compression of the small spring 6024 plus the compression of the large spring 6022. At this time, the shortening of the tension spring 601 is equal to the maximum compression of the small spring 6024 plus the compression of the large spring 6022.

[0118] The pressure N1' of the ultimate compression of the small spring 6024, the pressure N3 of the large spring 6022, and the tension N2' of the extension spring 601 are calculated using Hooke's Law. Finally, the pressure N' (i.e., mounting force) exerted by the chip held by the pick-up head 8 on the product to be mounted (e.g., a PCB board) is calculated using the following method:

[0119] The mounting force N' = the pressure of the limit compression of the small spring 6024 N1' + the pressure of the large spring 6022 N3 + the gravity G - the tension of the tension spring 601 N2'.

[0120] The gravity G is the total gravity of the suction head 8, hollow rotating shaft 504, secondary slide 501, second coupling 708, hollow ball spline shaft 703 and air extraction port 704.

[0121] This invention fixes a grating ruler 404 on a primary slide 401 and a reading head 503 on a secondary slide 501 at a position corresponding to the grating ruler. A spring assembly 6 is installed between the primary slide 401 and the secondary slide 501. The reading head reads the elongation of the tension spring 601 and the compression of the large spring 6022 and the small spring 6024 to obtain the pressure of the pick-up head 8 on the chip, thereby controlling the pressure on the chip. The pressure control is simple and has a low technical threshold. The chip placement head has a small overall structure and low cost. The chip placement head wiring is more convenient, and low-cost pressure precision control is achieved.

[0122] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A pressure-controllable chip mounter head characterized by comprising: The chip mounting head includes at least a fixed mounting base, a vertical drive assembly, a primary sliding assembly, and a secondary sliding assembly; The vertical drive assembly is mounted on the fixed mounting base; the primary sliding assembly includes at least one primary slide table. The vertical drive component is connected to the first-stage slide of the first-stage sliding component and is used to drive the first-stage slide to reciprocate in the vertical direction. The secondary sliding assembly includes at least a secondary slide table; a hollow rotating shaft is rotatably mounted inside the secondary slide table in the vertical direction, and a suction head is fixed at the bottom of the hollow rotating shaft; A spring assembly is installed between the primary slide and the secondary slide; a grating ruler is fixed on the primary slide, and a reading head is fixed on the secondary slide corresponding to the position of the grating ruler. The spring assembly includes a tension spring, one end of which is fixed to the primary slide and the other end of which is fixed to the secondary slide, so that the secondary slide is suspended below the primary slide and that the secondary slide moves freely in the vertical direction relative to the primary slide. The spring assembly further includes an adjusting spring assembly, which includes a spring guide post. The top of the spring guide post is fixed to the primary slide, and the bottom of the spring guide post is slidably inserted into the secondary slide. Specifically, a limiting nut and a limiting sleeve are fixed on the spring guide post, with the limiting sleeve located below the limiting nut; a large spring is sleeved on the spring guide post, and the large spring is located between the limiting nut and the limiting sleeve; A small spring is fitted onto the spring guide post, and the small spring is located between the limiting sleeve and the secondary slide.

2. The chip mounter head according to claim 1, characterized by The vertical drive assembly includes a first motor, a ball screw shaft, and a ball screw seat; The first motor is fixed on the fixed mounting base, and the ball screw shaft is connected to the output shaft of the first motor; the ball screw seat is fixed to the first-stage slide, and the ball screw shaft is installed in the ball screw seat and passes through the first-stage slide; When the first motor drives the ball screw shaft to rotate, the ball screw shaft drives the ball screw seat to reciprocate in the vertical direction, thereby driving the first-stage slide to reciprocate in the vertical direction.

3. The chip mounter head according to claim 2, characterized by The vertical drive assembly further includes a first motor mounting base, the first motor being fixed on the first motor mounting base, and the first motor mounting base being fixed on the fixed mounting base.

4. The chip mounter head according to claim 2, characterized by The output shaft of the first motor is connected to the ball screw shaft via a first coupling.

5. The chip mounter head according to claim 1, wherein The primary sliding assembly also includes a slide rail and a slider; The slider is fixed to the primary slide table, the slide rail is fixed to the fixed mounting base, and the slider is slidably connected to the slide rail; When the primary slide table reciprocates in the vertical direction, the slider reciprocates along the slide rail.

6. The chip mounter head according to Claim 1, wherein Cross roller guides are installed between the primary slide and the secondary slide.

7. The chip mounter head according to Claim 1, wherein The chip mounting head also includes a rotary drive assembly; The rotary drive assembly includes a second motor, a hollow ball spline shaft, and a ball spline seat; The second motor is fixed to the fixed mounting base, and the ball spline seat is rotatably mounted in the fixed mounting base; the second motor is used to drive the ball spline seat to rotate. The hollow ball spline shaft is installed in the ball spline seat. The hollow ball spline shaft is configured to reciprocate in the vertical direction relative to the ball spline seat, and to drive the hollow ball spline shaft to rotate when the ball spline seat rotates. The hollow ball spline shaft passes through the fixed mounting base and the first-stage slide, and is connected to the hollow rotating shaft; When the ball spline seat rotates, it drives the hollow ball spline shaft to rotate, which in turn drives the hollow rotating shaft and the suction head to rotate.

8. The chip mounter head according to claim 7, characterized by The outer surface of the hollow ball spline shaft is provided with a first ball groove extending in the vertical direction, and the inner surface of the ball spline seat is provided with a second ball groove extending in the vertical direction. Balls are installed in the first ball groove and the second ball groove, so that the hollow ball spline shaft reciprocates in the vertical direction relative to the ball spline seat, and the hollow ball spline shaft is driven to rotate when the ball spline seat rotates.

9. The chip mounter head according to claim 7, wherein The rotary drive assembly further includes a second motor mounting base, the second motor being fixed on the second motor mounting base, and the second motor mounting base being fixed on the fixed mounting base; The output shaft of the second motor is connected to the first pulley, and the ball spline seat fixes the second pulley; a belt is arranged around the first pulley and the second pulley; When the second motor drives the first pulley to rotate, the second pulley drives the ball spline seat to rotate.

10. The chip mounter head according to claim 7, wherein An air extraction port is installed on the top of the hollow ball spline shaft; The bottom of the hollow ball spline shaft is connected to the hollow rotating shaft via a second coupling.

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