Grinding clamp capable of being automatically lifted and overturned

Abstract

The grinding clamp comprises a lifting mechanism, a turnover mechanism, a clamp body and a supporting driving arm, the lifting mechanism is provided with a moving platform, the moving platform drives the turnover mechanism to ascend and descend, and the turnover mechanism is connected with the moving platform through a transverse turnover shaft; a supporting driving arm is fixedly arranged on the overturning mechanism and overturns with an overturning shaft as the axis, the supporting driving arm comprises a supporting base plate, a center hole is formed in the supporting base plate, the clamp body is provided with a driving ring, a liftable adsorption face is arranged in the middle of the driving ring, an upper fixing plate is arranged at the top of the driving ring, and the diameter of the upper fixing plate is larger than that of the center hole; the diameter of the driving ring is smaller than that of the center hole, the supporting driving arm is provided with a locking mechanism and a friction driving mechanism, the locking mechanism is used for clamping the upper fixing plate and fixing the upper fixing plate and the supporting base plate, and the friction driving mechanism is used for driving the driving ring to rotate so as to drive the clamp body to rotate. The turnover device is good in turnover stability, and the labor intensity of workers is relieved.

Description

Technical Field

[0001] This invention relates to a grinding fixture, belonging to the technical field of grinding equipment. Background Technology

[0002] During the wafer grinding and polishing process, a fixture holds the wafer / material on a grinding and polishing machine for precision machining. Simultaneously, the fixture needs to apply pressure to the surface of the wafer / material to ensure proper machining. When the wafer / material size is 8 inches in diameter or larger, a significant downward pressure needs to be applied to its surface to achieve a certain removal rate. Taking 8-inch silicon as an example, at 100 g / cm²... 2 Calculations show that approximately 32 kg of downward pressure is required during grinding. This large size and high pressure result in a relatively large and heavy precision grinding fixture, with large fixtures typically weighing over 40 kg. Furthermore, during grinding and polishing, the fixture needs to be flipped for wafer / material adsorption, cleaning, etc., requiring manual flipping, which is labor-intensive and poses safety risks. Chinese patent CN117655912A discloses a grinding fixture with a flipping mechanism. This mechanism uses a lifting pin to connect the polishing head. When flipping is needed, the lifting pin limits the grinding fixture head, facilitating manual flipping and keeping the head in the flipped state for easy cleaning and maintenance. However, this existing technology only applies to grinding fixtures driven by direct rotation; currently, there is no flipping mechanism suitable for grinding fixtures driven by lateral friction. Summary of the Invention

[0003] To address the shortcomings of the prior art, this invention provides an automatically lifting and flipping grinding fixture, solving the problem of stable flipping of heavy grinding fixtures driven by lateral friction.

[0004] The technical solution of this invention is as follows: A grinding fixture capable of automatic lifting and flipping includes a lifting mechanism, a flipping mechanism, a fixture body, and a support drive arm. The lifting mechanism is provided with a motion platform, which drives the flipping mechanism to rise and fall. The flipping mechanism and the motion platform are connected by a transverse flipping shaft. The support drive arm is fixedly mounted on the flipping mechanism. The flipping mechanism drives the support drive arm to flip about the flipping shaft. The support drive arm includes a support base plate with a central hole. The fixture body is provided with a drive ring with a liftable adsorption surface in the middle. The top of the drive ring is provided with an upper fixing plate. The diameter of the upper fixing plate is larger than the diameter of the central hole, and the diameter of the drive ring is smaller than the diameter of the central hole. The support drive arm is provided with a locking mechanism and a friction drive mechanism. The locking mechanism is used to clamp the upper fixing plate and fix the upper fixing plate to the support base plate. The friction drive mechanism is used to frictionally drive the drive ring to rotate, thereby causing the fixture body to rotate about a vertical axis.

[0005] Furthermore, the locking mechanism includes a locking bracket and a cylinder for driving the locking bracket to move vertically up and down. The locking bracket is disposed on the periphery of the central hole, and the upper fixing plate can be clamped and fixed by the locking bracket and the supporting base plate.

[0006] Furthermore, the locking brackets are evenly distributed around the central hole, and there are no fewer than three of them.

[0007] Furthermore, an L-shaped protective bracket is provided around the central hole on the support base plate, the protective bracket being used to prevent the upper fixing plate from vertically detaching.

[0008] Furthermore, the friction drive mechanism includes a drive motor, a main drive wheel, a limit wheel, a secondary drive wheel, and a drive belt. The drive motor drives the main drive wheel to rotate, and the main drive wheel drives the secondary drive wheel to rotate via the drive belt. The limit wheel cooperates with the secondary drive wheel to restrict the position of the drive ring, and the secondary drive wheel frictionally drives the drive ring to rotate.

[0009] Furthermore, a support column is fixed to the upper fixing plate, an upper plate is fixed to the upper part of the support column, and a weight block is detachably connected to the upper plate.

[0010] Furthermore, the upper plate is provided with a rotary joint, and the rotary joint is connected to a pipeline that provides vacuum and compressed gas to the clamp body. The weight block is provided with a notch to avoid the rotary joint and the pipeline.

[0011] Furthermore, a height sensor is provided on the bottom surface of the support substrate.

[0012] Furthermore, the lifting mechanism is fixedly provided with an upper adapter plate, the flipping mechanism is provided with a rear adapter plate and a side adapter block, the pipe of the clamping body is connected to the interface of the side adapter block, the interface of the side adapter block is transferred to the rear adapter plate in the flipping mechanism, and the rear adapter plate is connected to the upper adapter plate through a flexible flat cable.

[0013] Furthermore, the center height of the clamp body is the same as that of the flipping axis.

[0014] Compared with existing technologies, the advantages of the technical solution provided by this invention are as follows: This invention enables a friction-driven, self-rotating clamp to be lifted and flipped using a mechanical device, reducing manual labor intensity. The locking mechanism is independent of the friction drive mechanism that drives the clamp's rotation; vertical locking does not affect the circumferential positioning and driving of the friction drive mechanism. The structure is simple and offers good flipping stability. Attached Figure Description

[0015] Figure 1 This is a three-dimensional structural diagram of a grinding fixture that can be automatically lifted and flipped.

[0016] Figure 2 A structural diagram of the lifting mechanism.

[0017] Figure 3 This is a schematic diagram of the front structure of the flipping mechanism.

[0018] Figure 4 This is a schematic diagram of the rear structure of the flipping mechanism.

[0019] Figure 5 This is a schematic diagram of the three-dimensional structure of the clamping body.

[0020] Figure 6 This is a schematic diagram of the main structure of the clamping body.

[0021] Figure 7 A schematic diagram of the upper structure supporting the drive arm.

[0022] Figure 8 A schematic diagram of the lower structure supporting the drive arm.

[0023] Figure 9 This is a schematic diagram of an automatically lifting and flipping grinding fixture in its original position.

[0024] Figure 10 This is a schematic diagram of the tilting process of the fixture of an automatically lifting and tilting grinding jig.

[0025] Figure 11 This is a schematic diagram of the fixture body of an automatically lifting and rotating grinding jig that rotates 180 degrees. Detailed Implementation

[0026] The present invention will be further described below with reference to embodiments. It should be understood that these embodiments are only for illustrating the present invention and are not intended to limit the scope of the present invention. After reading this description, any modifications of this description in various equivalent forms by those skilled in the art will fall within the scope defined by the appended claims.

[0027] Please combine Figure 1 As shown in Figure 5, the grinding fixture that can be automatically lifted and flipped according to the embodiment of the present invention includes a lifting mechanism 1, a flipping mechanism 2, a fixture body 3 and a support drive arm 4.

[0028] The lifting mechanism 1 is fixed at its bottom to a (rotatable / left-right movable / fixed) platform, and has an internal Z-axis motion mechanism, including an internal motor slide rail (not shown) and a Z-axis motion platform 11. The tilting mechanism 2's tilting shaft 23 is connected and fixed to the lifting mechanism 1's fixed flange 12. During tilting, the tilting shaft 23 does not rotate, but the tilting mechanism 2 can rotate around the tilting shaft 23. The clamping body 3 is supported and driven by the support drive arm 4. The rear of the support drive arm 4 is fixed to the bottom of the tilting mechanism 2 with screws, forming an integral part with the tilting mechanism 2.

[0029] Please combine Figures 1 to 4 As shown, the Z-axis motion platform 11 of the lifting mechanism 1 has a fixed flange 12, which is connected to the flange of the tilting shaft 23 of the tilting mechanism 2. The tilting mechanism 2 has a high-torque reduction motor inside, which can drive the tilting mechanism 2 to rotate around the tilting shaft 23. The upper right corner of the lifting mechanism 1 has an upper adapter plate 13, the left rear side of the tilting mechanism 2 has a rear adapter plate 27, and the right side of the tilting unit 2 has a side adapter block 24, which has an upper adapter interface 25 and a lower adapter interface 26. The vacuum and CDA (compressed air) lines from the top of the clamping body 3 are first connected to the upper adapter interface 25, and then transferred to the rear adapter plate 27 inside the tilting mechanism 2; the air lines from the cylinder 42b of the locking mechanism 42 on the support drive arm 4, the control lines of the drive motor 43 and the height sensor 44 are first connected to the lower adapter interface 26, and then transferred to the rear adapter plate 27 inside the tilting mechanism 2. All these pipelines converge at the rear adapter plate 27, which is then connected to the upper adapter plate 13 via a flexible, supportable flat cable (not shown). Before the flipping mechanism 2, carrying the clamping body 3, flips the plate, the flexible, supportable flat cable connecting the rear adapter plate 27 and the upper adapter plate 13 forms an n-shape; after flipping 180 degrees, the cable forms a C-shape. This effectively prevents the pipelines from knotting and tangling during the flipping process. The flexible, supportable flat cable can also be protected using a bendable nylon cable chain, ensuring operational safety and extending the pipeline's lifespan.

[0030] Please combine Figure 5 and Figure 6As shown, a rotary joint 301 is fixed at the center of the upper plate 314 at the top of the clamp body 3, to which a vacuum inlet / outlet tube and a CDA tube are connected. The vacuum tube provides a vacuum to the adsorption surface 309, and the CDA provides a gas source to the cylinder inside the pressurization unit 304. The inlet tubes (vacuum and CDA) of the rotary joint 301 are bundled together and connected to the upper rotating interface 25 at the upper right corner of the flipping mechanism 2. The upper plate 314 of the clamp body 3 is connected to the upper fixed plate 307 by two support columns 311. The upper plate 314 is locked with a removable weight 302 by two quick-release pins 303 on the left and right sides, and the weight 302 has a notch to facilitate bypassing the upper vacuum tube and CDA tube when removing the weight 302. A vacuum joint 306 (one or more) is connected to the vacuum outlet line of the rotary joint 301 (not shown), and the other end is fixed to the adsorption surface 309. The vacuum adsorption surface 309 is connected to the spindle 310, which can move up and down within the spindle sleeve 305. A cylinder is fixed inside the pressurizing unit 304, connected to the outlet CDA line of the rotary joint 301. The end of the cylinder push rod is connected to the spindle 310, applying pressure to the spindle 310 during grinding and polishing. At the end of grinding and polishing, the adsorption surface 309 is raised, so that the surface of the processed wafer / material is lower than the surface of the drive ring 308, thus protecting the wafer / material. The pressure applied to the spindle 310 by the cylinder is indirectly applied to the adsorption surface 309, and the wafer / material is adsorbed onto the adsorption surface 309.

[0031] The upper plate 314 is fixed to two support columns 311, so the detachable weight 302 is supported by the support columns 311. The pressure is transmitted to the upper fixed plate 307 and the drive ring 308 through the support columns 311, and finally to the grinding and polishing pad. When the pressure required on the wafer surface is greater than the weight of the fixture itself, the weight of the weight 302 can be increased to increase the overall weight of the fixture; when the required pressure is less, the weight of the weight 302 can be reduced. Therefore, weights 302 of different weights can be used (the outer diameter or height of the weight can be changed to increase or decrease the weight, or different density materials can be used) to meet the different pressure requirements of the fixture (different processing materials have different processing pressure ranges, for example, the processing pressure of SiC and InP materials is very different). Moreover, the detachable weight also facilitates manual installation and maintenance of the fixture.

[0032] Please combine Figure 1 , Figure 7 and Figure 8As shown, the support drive arm 4 mainly consists of a support base plate 40, protective brackets 41, locking mechanisms 42, a drive motor 43, a height sensor 44, a main drive wheel 45, a limit wheel 46, a secondary drive wheel 47, a tension wheel 48, and a drive belt 49. The diameter of the upper fixed plate 307 of the clamp body 3 is larger than the diameter of the central hole of the support base plate 40, while the diameter of the drive ring 308 is smaller than the diameter of the central hole. Therefore, the entire large clamp can be placed in the central hole of the support base plate 40. Three protective brackets 41 limit the vertical movement range of the upper fixed plate 307 of the clamp body 3 and provide protection during flipping to prevent the upper fixed plate 307 from directly detaching vertically. Three locking mechanisms 42 are evenly distributed around the central hole. The locking mechanism 42 includes a locking bracket 42a and a cylinder 42b, and the cylinder drives the locking bracket 42a to move vertically. When pressure is applied, the locking mechanism 42 can press the upper fixing plate 307 onto the support base plate 40 through the locking bracket 42a to prevent the clamp body 3 from loosening during the flipping process.

[0033] The friction drive mechanism consists of a drive motor 43, a main drive wheel 45, a limiting wheel 46, a secondary drive wheel 47, a tensioning wheel 48, and a drive belt 49. Except for the drive motor 43, which is mounted above the support base plate 40, all other components are mounted below the support base plate 40. The two limiting wheels 46 and the secondary drive wheel 47 at the lower part of the support drive arm 4 limit and center the clamping body 3. The drive motor 43 directly drives the main drive wheel 45 to rotate. Driven by the main drive wheel 45 and the drive belt 49, the two secondary drive wheels 47 can drive the clamping body 3 (the secondary drive wheels 47 directly rub against the friction drive ring 308) to rotate on the grinding and polishing disc.

[0034] The lifting mechanism 1 has two main positions: the home position and the working position. In the home position, the clamping body 3 is lifted, away from the grinding and polishing disk. When the lifting mechanism 1 moves from the home position to the working position via the Z-axis, the clamping body 3 descends, and the height sensor 45 on the support drive arm 4 measures the distance to the surface of the grinding and polishing disk in real time. As it approaches, the descent speed slows down until the bottom surface of the drive ring 308 contacts the disk surface. During contact and the aforementioned descent, the overall weight of the clamping body 3 is pressed against the support base plate 40 of the support drive arm 4 by the upper fixing plate 307. After contact, the clamping body 3 falls onto the grinding and polishing disk, the drive ring 308 contacts the disk surface, and the adsorption surface 309 is in a state of being pulled upwards by the cylinder inside the pressurization unit 304. Therefore, the wafer / material processing surface does not contact the disk surface. The support drive arm 4 continues to move downward a short distance, causing the upper fixing plate 307 of the clamp body 3 to disengage from the support base plate 40 of the support drive arm 4, maintaining a certain distance. The upper fixing plate 307 is also a certain distance from the protective bracket 41. Thus, the bottom surface of the drive ring 308 of the clamp body 3 only contacts the disk surface, and the sides of the drive ring 308 only contact the two limit wheels 46 and the two secondary drive wheels 47. Other parts of the clamp body 3 do not contact the support drive arm 4 and can rotate freely on the disk surface. At this time, the cylinder inside the pressurizing unit 304 can release the adsorption surface 309, causing it to fall and contact the surface of the grinding and polishing disk. When the grinding and polishing is finished, the lifting mechanism 1 moves the support drive arm 4 upward until the upper fixing plate 307 of the clamp body 3 contacts the support base plate 40. The support drive arm 4 continues to move upward, at which point the three locking mechanisms 42 begin to work, pressing down to clamp the upper fixing plate 307 onto the support base plate 40. The support drive arm 4 continues to move upward until it stops in its original position. Once it is confirmed that the three locking mechanisms 42 have locked the clamp body 3, the flipping mechanism 2 can perform a leftward flipping motion. The flipping mechanism 2 has an internal flipping angle sensor (not shown) that detects the flipping angle in real time and can stop flipping at any time, with a maximum flipping angle of 180 degrees. For example, it can stop at 45 degrees to rinse and dry the surface of the processed material. It stops at 180 degrees, and the flipping mechanism 2 has an internal stop mechanism (not shown) to prevent exceeding 180 degrees. To minimize the torque generated by the clamp body 3 on the flipping mechanism 2 during flipping, the center of gravity of the clamp body 3 is designed and controlled to be approximately at the same height as the axis 22 of the flipping shaft 23.

[0035] Figures 9 to 11 The flipping process is shown. Figure 9 In order to lift the plate from the surface back to its original position, the three locking mechanisms 42 press down to press the upper fixing plate 307 onto the support base plate 40. Figure 10 This is the state where the rotation begins to the left. Figure 11This is the position after rotating 180 degrees and stopping. In this position, the cylinder in the pressurizing unit 304 of the clamp body 3 acts to push the upper adsorption surface 309 out above the lower surface of the drive ring 308. This facilitates the placement and removal of the workpiece. After the workpiece is placed on the adsorption surface 309, it is vacuum-adsorbed. Then, the cylinder in the pressurizing unit 304 is controlled to pull the adsorption surface 309 back below the working surface of the drive ring 309. After confirming that the three locking mechanisms 42 have locked the clamp body 3, the flipping mechanism 2 can perform a reverse flip until it is rotated 180 degrees and the working surface of the drive ring 309 faces downward. Then, following the aforementioned actions, the lifting mechanism 1 can be controlled to move towards the working position, so that the clamp body 3 falls completely onto the grinding and polishing disc.

Claims

1. A grinding fixture capable of automatic lifting and tilting, characterized in that, The device includes a lifting mechanism, a flipping mechanism, a clamping body, and a support drive arm. The lifting mechanism has a motion platform that drives the flipping mechanism to rise and fall. The flipping mechanism is connected to the motion platform via a transverse flipping shaft. The support drive arm is fixedly mounted on the flipping mechanism. The flipping mechanism drives the support drive arm to flip around the flipping shaft. The support drive arm includes a support base plate with a central hole. The clamping body has a drive ring with a liftable suction surface in the middle. The top of the drive ring has an upper fixing plate with a diameter larger than the diameter of the central hole and a diameter smaller than the diameter of the central hole. The support drive arm has a locking mechanism and a friction drive mechanism. The locking mechanism clamps the upper fixing plate and fixes it to the support base plate. The friction drive mechanism drives the drive ring to rotate, causing the entire clamping body to rotate around a vertical axis.

2. The automatically lifting and rotating grinding fixture according to claim 1, characterized in that, The locking mechanism includes a locking bracket and a cylinder that drives the locking bracket to move vertically up and down. The locking bracket is disposed on the periphery of the central hole, and the upper fixing plate can be clamped and fixed by the locking bracket and the supporting base plate.

3. The automatically lifting and rotating grinding fixture according to claim 2, characterized in that, The locking brackets are evenly distributed around the central hole, and there are no fewer than three of them.

4. The automatically lifting and rotating grinding fixture according to claim 1, characterized in that, The support base plate is provided with an L-shaped protective bracket around the central hole, which is used to prevent the upper fixing plate from detaching vertically.

5. The automatically lifting and rotating grinding fixture according to claim 1, characterized in that, The friction drive mechanism includes a drive motor, a main drive wheel, a limit wheel, a secondary drive wheel, and a drive belt. The drive motor drives the main drive wheel to rotate, and the main drive wheel drives the secondary drive wheel to rotate via the drive belt. The limit wheel cooperates with the secondary drive wheel to limit the position of the drive ring, and the secondary drive wheel frictionally drives the drive ring to rotate.

6. The automatically lifting and rotating grinding fixture according to claim 1, characterized in that, A support column is fixed to the upper fixing plate, and an upper plate is fixed to the upper part of the support column. A weight block is detachably connected to the upper plate.

7. The automatically lifting and rotating grinding fixture according to claim 6, characterized in that, The upper plate is provided with a rotary joint, and the rotary joint is connected to a pipeline that provides vacuum and compressed gas to the clamp body. The weight block is provided with a notch to avoid the rotary joint and the pipeline.

8. The automatically lifting and rotating grinding fixture according to claim 1, characterized in that, A height sensor is provided on the bottom surface of the support substrate.

9. The automatically lifting and rotating grinding fixture according to claim 1, characterized in that, The lifting mechanism is fixedly provided with an upper adapter plate, the flipping mechanism is provided with a rear adapter plate and a side adapter block, the pipe of the clamping body is connected to the interface of the side adapter block, the interface of the side adapter block is transferred to the rear adapter plate in the flipping mechanism, and the rear adapter plate is connected to the upper adapter plate through a flexible flat cable.

10. The automatically lifting and rotating grinding fixture according to claim 1, characterized in that, The center height of the clamp body is the same as that of the flipping shaft.

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