Adjustable clamp for high-precision plane part machining of single-shaft polishing machine

Abstract

The adjustable clamp for high-precision plane part machining of the single-shaft polishing machine comprises a rotating disc, a sliding groove disc, an extension rod and a fixing block, and the rotating disc and the sliding groove disc are coaxially arranged and can rotate relative to each other; a screw hole for mounting a set screw is formed in the turntable; the sliding groove disc is provided with sliding grooves in the radial direction, correspondingly, the rotary disc is provided with arc grooves, the arc grooves and the sliding grooves are arranged in pairs to form composite track grooves, and the composite track grooves are arranged in groups in the circumferential direction. The extension rod is arranged in the sliding groove, a fixing block is arranged at the outer end of the extension rod, and the fixing block is rotationally connected with the extension rod. Cylindrical rods are arranged at the inner ends of the extension rods and matched with the arc grooves. The clamp can meet the machining requirements of workpieces of different sizes and different shapes, and operation is easy. In the machining process, the non-pressure polishing effect can be achieved, meanwhile, the movement track of a workpiece on the grinding disc can be controlled, and the machining technology can be adjusted easily.

Description

Technical Field

[0001] The invention relates to the technical field of precision machining, in particular to an adjustable fixture used for machining high-precision plane parts of a single-axis polishing machine. Background Art

[0002] High-precision, large-size flat parts are widely used in the fields of semiconductors, national defense, aerospace, etc. For the final processing of high-precision flat parts, the current main process is to use a single-axis polishing machine or a ring polishing machine for grinding and polishing.

[0003] Chinese patent CN111414685A discloses a coordinate mapping control method in the polishing process of a numerically controlled single-axis polishing machine, wherein the structure of the single-axis polishing machine is described, wherein the numerically controlled single-axis polishing machine includes a stylus, a swing arm, a translation arm, a single-axis machine bed platform, and a grinding disc, wherein an optical element is arranged on the single-axis machine bed platform, the stylus is connected to the single-axis machine bed platform through a swing arm link and a translation arm link, and the grinding disc is arranged at the end of the stylus. When a single-axis polishing machine is used to process planar parts, a pressure head is usually used to be pasted on the back of the workpiece, and then a swing shaft (stylus) is placed in the inner hole of the pressure head, and high-precision processing of the workpiece is achieved by the swing of the swing shaft (stylus), and the pressure head is removed after processing. Due to the deadweight of the pressure head and the bonding effect of glue, the shape of thin planar parts is very easy to change after the pressure head is removed. When the workpiece has high surface accuracy requirements, it is often necessary to repeat multiple processing for shaping, which is difficult to process and inefficient.

[0004] Chinese patent CN109664179A discloses a ring polishing machine, including a frame fixed with a polishing disc, a polishing mold cast on the upper surface of the polishing disc, a connecting rod fixed on the cantilever of the polishing machine frame, and a bearing-type correction disc connected to the connecting rod and placed on the polishing mold. When the ring polishing machine is used to process planar parts, the workpiece is placed in the workpiece ring (bearing-type correction disc), and is driven by the caliper and the swing mechanism (connecting rod) to rotate synchronously with the direction of rotation of the polishing disc. The workpiece ring of the ring polishing machine is slightly larger than the workpiece. During the processing, it can be determined whether to apply pressure on the workpiece according to the needs, so that pressure-free polishing can be achieved. However, due to the limitation of the swing mechanism of the ring polishing machine, the motion trajectory of the workpiece is relatively fixed, and the range of motion trajectory movement is small, which is not conducive to the process adjustment of the processing process. At the same time, when the ring polishing machine is used to process workpieces of different sizes, it is necessary to use a workpiece ring of matching size. If the diameter of the workpiece ring is much larger than the size of the workpiece, the workpiece will move freely in the workpiece ring, and it is difficult to control the motion trajectory of the workpiece. To process a circular workpiece, workpiece rings of different diameters are required; to process special-shaped workpieces, such as polygonal, elliptical or irregularly shaped workpieces, specific fixtures need to be made, which is inefficient and costly. Due to the limitations of the ring polishing machine structure, the workpiece ring can only play a limiting role, and the workpiece ring cannot be controlled to swing on the polishing disc. The movement trajectory of the workpiece on the polishing machine has a small range of movement, making it difficult to achieve a high surface accuracy. Summary of the invention

[0005] In order to overcome the deficiencies in the prior art, the present invention provides an adjustable fixture for high-precision flat parts processing of a single-axis polishing machine, which can adapt to the processing requirements of workpieces of different sizes and shapes, limit them, and achieve higher processing efficiency and reduce processing costs. The present invention combines the characteristics of ring polishing and single-axis processing, so that flat parts can achieve the effect of pressureless polishing when processed by a single-axis polishing machine, thereby improving the processing effect; at the same time, it can control the motion trajectory of the workpiece on the grinding disc, which is conducive to the process adjustment of the processing process.

[0006] The technical solution of the present invention is as follows:

[0007] The adjustable fixture for high-precision flat parts processing of a single-axis polishing machine comprises a coaxially arranged turntable and a slide plate, wherein the turntable and the slide plate can rotate relative to each other; a screw hole for installing a set screw is provided on the turntable, and when clamping a workpiece, the set screw is installed and tightened in the screw hole so that it abuts against the slide plate, thereby limiting the rotation between the turntable and the slide plate; a pressure head is provided on the turntable, and a mounting hole for connecting a swing shaft of a single-axis machine is provided on the pressure head; a slide groove is radially provided on the slide plate, and correspondingly, an arc groove is provided on the turntable, and the arc groove and the slide groove are arranged in pairs to form a composite track groove, and the composite track groove is arranged in groups in the circumferential direction; a slidable extension rod is provided in the slide groove, and a fixed block is provided at the outer end of the extension rod, and the fixed block is rotatably connected to the extension rod; a cylindrical rod is provided at the inner end of the extension rod, and the cylindrical rod cooperates with the arc groove. When the turntable rotates, the cylindrical rod moves along the arc groove and drives the extension rod to move linearly in the slide groove.

[0008] Compared with the prior art, the adjustable fixture for high-precision flat parts processing of a single-axis polishing machine of the present invention realizes the adjustability of the fixture through a specific structure, and can adjust the clamping size and angle of the fixture according to the size and shape of the workpiece to fix the workpiece. At the same time, the fixture is used to bear the weight, thereby realizing pressure-free polishing, and has made significant progress, as follows:

[0009] 1) Wide application range; the fixture of the present invention can adjust the fixed size and angle, and is suitable for workpieces of different sizes. There is no need to prepare multiple fixtures separately, which reduces the processing cost.

[0010] 2) Good processing effect; the clamp of the present invention can be directly connected to the swing shaft of the single-axis machine, and the pressure is borne by the clamp. After clamping, a gap will be retained between the clamp and the workpiece, so that the workpiece reaches an unconstrained state, and pressure-free polishing is achieved, thereby ensuring the processing effect; at the same time, the movement trajectory of the workpiece on the grinding wheel is controlled by the swing shaft of the single-axis machine. During polishing, the workpiece can not only rotate on the grinding wheel, but also swing on the grinding wheel. The surface shape of the entire grinding wheel can be utilized during polishing, thereby improving the processing efficiency and realizing high-precision processing of the surface shape of planar parts.

[0011] 3) Easy to operate; the clamp of the present invention is used to limit the position of the workpiece. In the process of clamping the workpiece, the workpiece is placed on the grinding disc, and then the clamp is placed on the periphery of the grinding disc. The turntable on the clamp is rotated to adjust the angle of the fixed block according to the shape of the workpiece. After meeting the processing requirements, the bolts are tightened to complete the clamping of the workpiece.

[0012] Furthermore, in the above-mentioned adjustable fixture for high-precision flat parts processing of a single-axis polishing machine, the slide groove plate is evenly provided with slide grooves at equal angles along the radial direction, and correspondingly, the turntable is evenly provided with arc grooves at equal angles around the axis.

[0013] Furthermore, in the above-mentioned adjustable fixture for high-precision flat parts processing of a single-axis polishing machine, the shape of the fixing block is an arc. Setting the fixing block in an arc shape can quickly locate the workpiece, reduce adjustment time, thereby improving work efficiency, and at the same time has strong adaptability, which is conducive to clamping workpieces of different shapes.

[0014] Furthermore, in the above-mentioned adjustable fixture for high-precision flat parts processing of a single-axis polishing machine, a PEEK block is provided on the fixed block. The PEEK block has the characteristics of self-lubricity, corrosion resistance, hydrolysis resistance, fatigue resistance, high temperature resistance, high mechanical strength, etc., wherein the self-lubricity can reduce the deformation and wear of the grinding disc of the ring polishing machine, and the corrosion resistance and hydrolysis resistance ensure the service life of the fixture when it is in contact with the grinding fluid for a long time. Further, the PEEK block is provided with a groove for the flow of the polishing liquid. Through the groove, the polishing liquid can quickly enter the contact surface between the workpiece and the grinding disc during polishing, thereby ensuring the polishing effect.

[0015] Furthermore, in the above-mentioned adjustable fixture for high-precision flat parts processing of a single-axis polishing machine, the turntable and the slide plate are connected by bolts. By connecting the turntable and the slide plate by bolts, the bolts can be tightened after clamping the workpiece to further limit the relative rotation between the turntable and the slide plate.

[0016] Furthermore, in the above-mentioned adjustable fixture for high-precision flat parts processing of a single-axis polishing machine, the turntable is provided with screw holes distributed in groups along the circumference of the turntable to form a screw hole group; the screw hole group has multiple groups, and each screw hole group is staggered in the circumference of the turntable. The staggered distribution of the screw hole groups in the circumference of the turntable can avoid the screw holes and the slide grooves in the slide groove plate from overlapping when clamping the workpiece, resulting in the phenomenon that the turntable and the slide groove plate rotate during the processing. Further, the screw hole group can be composed of 3-5 screw holes.

[0017] Furthermore, in the above-mentioned adjustable fixture for high-precision flat parts processing of a single-axis polishing machine, the fixed block and the extension rod are fixedly connected by threads. The threaded connection method can facilitate the installation and removal of the fixed block. When the workpiece is small, the fixed block can be removed to clamp the small workpiece, avoiding interference between the fixed blocks.

[0018] Furthermore, in the above-mentioned adjustable fixture for high-precision planar parts processing of a single-axis polishing machine, the number of the compound trajectory grooves may be 6-10. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a structural schematic diagram of an adjustable fixture for high-precision flat parts processing of a single-axis polishing machine according to the present invention;

[0020] Figure 2It is a schematic diagram of the bottom structure of the adjustable fixture used for high-precision flat parts processing of a single-axis polishing machine of the present invention;

[0021] Figure 3 This is a schematic diagram of the structure of the turntable in the adjustable fixture used for high-precision flat parts processing of a single-axis polishing machine of the present invention.

[0022] Figure 4 It is a schematic diagram of a large-sized disc clamped by an adjustable fixture for high-precision flat parts processing of a single-axis polishing machine according to the present invention;

[0023] Figure 5 It is a schematic diagram of a clamping medium-sized disc of an adjustable fixture for high-precision flat parts processing of a single-axis polishing machine according to the present invention;

[0024] Figure 6 It is a schematic diagram of a small-sized disc clamped by an adjustable fixture for high-precision flat parts processing of a single-axis polishing machine according to the present invention;

[0025] Figure 7 It is a schematic diagram of clamping a polygonal workpiece by an adjustable fixture for high-precision flat parts processing of a single-axis polishing machine according to the present invention;

[0026] Figure 8 It is a surface accuracy diagram of the polished ceramic disc held by a traditional indenter measured using a laser interferometer;

[0027] Fig. 9 The invention discloses a surface accuracy diagram of a ceramic disc after being polished which is clamped by an adjustable clamp and is used for machining high-precision flat parts of a single-axis polishing machine by using a laser interferometer.

[0028] The markings in the attached drawings are: 1-turntable; 101-arc groove; 102-screw hole; 2-slide plate; 201-slide; 3-extension rod; 4-fixing block; 5-bolt; 6-cylindrical rod; 7-PEEK block; 701-groove; 8-pressing head. DETAILED DESCRIPTION

[0029] The present invention is further described below in conjunction with the accompanying drawings and embodiments, but they are not intended to serve as the basis of the present invention.

[0030] Example (see Figure 1-9 ):

[0031] The adjustable fixture for high-precision flat parts processing of a single-axis polishing machine comprises a coaxially arranged turntable 1 and a slide plate 2, wherein the turntable 1 and the slide plate 2 can rotate relative to each other; the turntable 1 is provided with a screw hole 102 for installing a set screw, and when clamping a workpiece, the set screw is installed and tightened in the screw hole 102 so that it abuts against the slide plate 2, thereby limiting the rotation between the turntable 1 and the slide plate 2; the turntable 1 is provided with a pressure head 8, and the pressure head 8 is provided with a mounting hole for connecting the swing shaft of the single-axis machine; the slide plate 2 is provided with a slide groove 201 in the radial direction, and the corresponding The turntable 1 is provided with an arc groove 101, and the arc groove 101 and the slide groove 201 are arranged in pairs to form a compound track groove, and the compound track grooves are arranged in groups in the circumferential direction; a slidable extension rod 3 is arranged in the slide groove 201, and a fixed block 4 is arranged at the outer end of the extension rod 3, and the fixed block 4 is rotatably connected to the extension rod 3; a cylindrical rod 6 is arranged at the inner end of the extension rod 3, and the cylindrical rod 6 cooperates with the arc groove 101. When the turntable 1 rotates, the cylindrical rod 6 moves along the arc groove 101 and drives the extension rod 3 to make a linear motion in the slide groove 201.

[0032] like Figure 3 , Figure 5 , Figure 6 As shown, when clamping a workpiece, the angle of the fixing block 4 can be adjusted to make the clamp adapt to workpieces of different sizes and shapes.

[0033] In this embodiment, the fixing block 4 is in an arc shape, which can quickly locate the workpiece and reduce the adjustment time, thereby improving the work efficiency, and has strong adaptability, which is conducive to the clamping of workpieces of different shapes.

[0034] In this embodiment, a PEEK block 7 is provided on the fixed block 4. The PEEK block 7 has the characteristics of self-lubrication, corrosion resistance, hydrolysis resistance, fatigue resistance, high temperature resistance, high mechanical strength, etc., wherein the self-lubrication can reduce the deformation and wear of the grinding disc of the ring polishing machine, and the corrosion resistance and hydrolysis resistance ensure the service life of the fixture when it is in contact with the grinding fluid for a long time.

[0035] In this embodiment, the PEEK block 7 is provided with grooves 701 for the polishing liquid to flow. The grooves allow the polishing liquid to quickly enter the contact surface between the workpiece and the grinding disc during polishing, thereby ensuring the polishing effect.

[0036] In this embodiment, the rotating disk 1 is connected to the chute disk 2 by bolts 5. By connecting the rotating disk 1 and the chute disk 2 by bolts 5, the bolts 5 can be tightened after clamping the workpiece to further limit the relative rotation between the rotating disk 1 and the chute disk 2.

[0037] In this embodiment, the turntable 1 is provided with screw holes 102 distributed in groups along the circumference of the turntable to form screw hole groups; the screw hole groups include multiple groups, and the screw hole groups are staggered in the circumference of the turntable 1. The staggered distribution of the screw hole groups in the circumference of the turntable 1 can avoid the screw holes 102 and the slide grooves 201 in the slide groove plate 2 from overlapping after the workpiece is clamped, resulting in the phenomenon that the turntable 1 and the slide groove plate 2 rotate during the processing.

[0038] In this embodiment, the screw hole group consists of four screw holes 102 .

[0039] In this embodiment, the fixing block 4 is fixedly connected to the extension rod 3 by means of threads. The threaded connection method can facilitate the installation and removal of the fixing block 4. Figure 4 As shown, when the workpiece is small, the fixing blocks 4 can be disassembled to clamp the workpiece and avoid interference between the fixing blocks 4.

[0040] In this embodiment, the number of the compound track grooves is 8.

[0041] The ceramic disc is clamped by the adjustable fixture of the present invention and the iron pressure head is pasted on the ceramic disc. The ceramic disc is processed by a single-axis polishing machine. The final surface accuracy of the two ceramic discs is observed to verify the processing effect of the adjustable fixture for high-precision flat parts processing of the single-axis polishing machine of the present invention. The experimental steps are as follows:

[0042] S1: Use the same process to grind two ceramic discs to similar surface accuracy.

[0043] S2: Take one of the ceramic discs and clamp it with the adjustable clamp of the present invention, and use a resin adhesive to fix the iron pressure head at the center of the ceramic disc for control.

[0044] S3: Set the same spindle speed, swing shaft speed, and polishing liquid flow rate to process two ceramic discs.

[0045] S4: After the processing is completed, remove the indenter from the ceramic disc with the iron indenter, and remove the resin adhesive adhering to the surface of the ceramic disc. Use a laser interferometer to measure the surface shapes of the two ceramic discs respectively.

[0046] The test results show that the surface accuracy of the ceramic plate processed by the adjustable fixture of the present invention is PV = 0.561 μm, and the surface accuracy of the ceramic plate clamped by the traditional pressure head is PV = 0.877 μm. Figure 8 , Fig. 9As shown, by comparing the measured images, it can be found that the ceramic disc processed by the adjustable fixture of the invention has a more uniform surface shape, and the ceramic disc clamped by the traditional pressure head presents a convex shape with a high middle and low sides after processing. It can be concluded that the adjustable fixture for high-precision flat parts processing of the single-axis polishing machine of the present invention can obtain higher surface accuracy when processing flat parts, the surface shape is more uniform, and the processing efficiency is higher. The present invention enables flat parts to achieve the effect of pressure-free polishing when processed by a single-axis polishing machine, avoiding the influence of the deadweight of the pressure head and the bonding effect of glue on the surface shape of flat parts during the processing process, and has certain advantages compared to traditional pressure head fixtures.

[0047] The above general description of the invention involved in this application and the description of its specific implementation methods should not be understood as limiting the technical solutions of the invention. Based on the disclosure of this application, those skilled in the art can add, reduce or combine the disclosed technical features in the above general description and / or specific implementation methods (including examples) without violating the constituent elements of the invention involved, to form other technical solutions within the scope of protection of this application.

Claims

1. An adjustable fixture for high-precision flat parts processing on a single-axis polishing machine, characterized by: The invention comprises a coaxially arranged turntable (1) and a slide plate (2), wherein the turntable (1) and the slide plate (2) can rotate relative to each other; the turntable (1) is provided with a screw hole (102) for installing a set screw, and when clamping a workpiece, the set screw is installed and tightened in the screw hole (102) so that it abuts against the slide plate (2), thereby limiting the rotation between the turntable (1) and the slide plate (2); the turntable (1) is provided with a pressure head (8), and the pressure head (8) is provided with a mounting hole for connecting the swing shaft of a single-axis machine; the slide plate (2) is provided with a slide groove (201) in the radial direction, and correspondingly, the turntable (1) is provided with a circular arc groove (102) 01), the circular arc groove (101) and the slide groove (201) are arranged in pairs to form a composite track groove, and the composite track grooves are arranged in groups in the circumferential direction; a slidable extension rod (3) is arranged in the slide groove (201), and a fixed block (4) is arranged at the outer end of the extension rod (3), and the fixed block (4) and the extension rod (3) are rotatably connected; a cylindrical rod (6) is arranged at the inner end of the extension rod (3), and the cylindrical rod (6) and the circular arc groove (101) cooperate with each other. When the turntable (1) rotates, the cylindrical rod (6) moves along the circular arc groove (101) and drives the extension rod (3) to make a linear motion in the slide groove (201).

2. The adjustable fixture for high-precision flat parts processing of a single-axis polishing machine according to claim 1 is characterized in that: The slide groove plate (2) is provided with slide grooves (201) at uniform angles along the radial direction, and correspondingly, the rotating disk (1) is provided with arc grooves (101) at uniform angles around the axis.

3. The adjustable fixture for high-precision flat parts processing of a single-axis polishing machine according to claim 1 is characterized in that: The fixing block (4) is in the shape of an arc.

4. The adjustable fixture for high-precision flat parts processing of a single-axis polishing machine according to claim 1 is characterized in that: A PEEK block (7) is provided on the fixed block (4).

5. The adjustable fixture for high-precision flat parts processing of a single-axis polishing machine according to claim 2 is characterized in that: The PEEK block (7) is provided with a groove (701) for the polishing liquid to flow.

6. The adjustable fixture for high-precision flat parts processing of a single-axis polishing machine according to claim 1 is characterized in that: The rotating disk (1) is connected to the chute disk (2) via bolts (5).

7. The adjustable fixture for high-precision flat parts processing of a single-axis polishing machine according to claim 1 is characterized in that: The turntable (1) is provided with screw holes (102) distributed in groups along the circumference of the turntable to form screw hole groups; the screw hole groups include a plurality of groups, and the screw hole groups are staggered in the circumference of the turntable (1).

8. The adjustable fixture for high-precision flat parts processing of a single-axis polishing machine according to claim 7 is characterized in that: The screw hole group consists of 3-5 screw holes (102).

9. The adjustable fixture for high-precision flat parts processing of a single-axis polishing machine according to claim 1 is characterized in that: The fixing block (4) is fixedly connected to the extension rod (3) via threads.

10. The adjustable fixture for high-precision flat parts processing of a single-axis polishing machine according to claim 1 is characterized in that: The number of the composite track grooves is 6-10.

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