A thin-walled part positioning and clamping device

Abstract

This invention discloses a positioning and clamping device for thin-walled parts, including a hydraulic clamping module and a quick positioning module. The hydraulic clamping module includes a base, and an expansion sleeve is installed in the inner cavity of the base, forming a sealed hydraulic oil chamber between the expansion sleeve and the inner cavity sidewall of the base. The quick positioning module includes a positioning shaft, and a disc is coaxially arranged at the lower part of the positioning shaft. The bottom of the positioning shaft passes through the disc and mates with a central positioning hole on the bottom surface of the inner cavity of the base. The positioning shaft is assembled in the inner cavity of the base. An installation hole is opened on the side of the disc and extends into the disc. A positioning block is installed in the installation hole by a spring. The front end of the positioning block has a toothed structure, and the spring can push the front end of the positioning block to the outside of the disc. A connecting groove communicating with the installation hole is opened on the upper surface of the disc. The lower end of the handle is inserted into the connecting groove and connected to the positioning block by a pin. A through groove is opened on the positioning shaft. The handle passes through the through groove, and the middle part of the handle is installed in the through groove by a pin.

Description

Technical Field

[0001] This invention relates to the field of parts processing, and specifically to a positioning and clamping device for thin-walled parts. Background Technology

[0002] Thin-walled parts, due to their thin walls and poor rigidity, are prone to deformation during machining. This makes it difficult to maintain dimensional requirements after the parts have recovered from deformation. In particular, when machining precision thin-walled parts with angular positioning, relying solely on external clamping is insufficient to meet machining accuracy requirements. Currently, the common machining method is to align and clamp the workpiece before machining. However, this not only affects machining efficiency but also causes deformation of the parts under clamping force, impacting the dimensional accuracy, shape accuracy, and surface roughness of the workpiece.

[0003] Currently, when machining thin-walled parts that use internal teeth for angular positioning, a three-jaw chuck or other device is often used to clamp the outer circle of the part. The angular position is aligned before machining. However, in actual use, it is often difficult to control the clamping force. Excessive clamping force will cause deformation of the workpiece clamping part, while insufficient clamping force will cause the part to loosen during machining. In addition, thin-walled parts are prone to vibration and deformation during machining, resulting in a low machining pass rate.

[0004] Chinese invention patent application CN110227957A discloses a hydraulic clamp for milling shaft parts. The method involves placing an oil pipe and nut into the positioning holes of the clamp's elastic sleeve, positioning the oil pipe and nut axially and radially, and then injecting hydraulic oil into each cylinder to move the movable clamp's elastic sleeve downwards. The outer cone of the clamp's elastic sleeve contacts the inner cone of the clamp's spring body and tightens, thereby clamping the oil pipe and nut. This method lacks an angular limiting device and is not suitable for positioning and clamping thin-walled parts. Summary of the Invention

[0005] The purpose of this invention is to provide a positioning and clamping device for thin-walled parts, which can quickly position and clamp thin-walled parts, while significantly reducing the deformation of the workpiece during clamping and processing, thereby improving the processing accuracy and efficiency of thin-walled parts.

[0006] To achieve the above objectives, the present invention employs the following technical solution:

[0007] A positioning and clamping device for thin-walled parts, wherein the thin-walled parts are cylindrical parts with internal teeth, the device includes a hydraulic clamping module and a quick positioning module, the hydraulic clamping module includes a base, the inner cavity of the base is equipped with an expansion sleeve, and a cavity machined on the outer wall of the expansion sleeve and the inner cavity sidewall of the base form a sealed hydraulic oil cavity.

[0008] The base has one or more pressurization holes leading to the hydraulic oil chamber along the radial direction on its side, and an exhaust hole leading to the hydraulic oil chamber is also provided on its side.

[0009] The quick positioning module includes a positioning shaft, with a disc coaxially mounted on its lower part. The bottom of the positioning shaft passes through the disc and mates with a central positioning hole on the bottom surface of the base cavity. The positioning shaft is assembled in the inner cavity of the base. A mounting hole is formed on the side of the disc, extending into the disc. A positioning block is mounted in the mounting hole via a spring. The front end of the positioning block has a toothed structure, and the spring can push the front end of the positioning block to the outside of the disc. A connecting groove communicating with the mounting hole is formed on the upper surface of the disc. The lower end of the handle is inserted into the connecting groove and connected to the positioning block via a pin. A through groove is formed on the positioning shaft, through which the handle passes. The middle part of the handle is mounted in the through groove via a pin.

[0010] Furthermore, a positioning ring plate is provided at the upper end of the expansion sleeve, and annular grooves are provided at the bottom of the positioning ring plate and the lower end of the outer wall of the expansion sleeve. The cavity is machined on the outer wall of the expansion sleeve, and the cavity is located between the two annular grooves. A sealing ring and a sealing ring are respectively installed in the two annular grooves. When the expansion sleeve is assembled on the base, the positioning ring plate of the expansion sleeve is stuck on the upper edge of the inner cavity of the base. In this way, the cavity between the sealing ring and the sealing ring and the inner cavity side wall of the base form the hydraulic oil cavity.

[0011] Furthermore, the outer end of the pressure hole is provided with a stepped threaded hole, and a plunger is installed inside the pressure hole. The plunger has two annular grooves, and a sealing ring is installed in the annular grooves. A bolt is installed in the stepped threaded hole, and the bolt is connected to the plunger by a left-hand thread.

[0012] Furthermore, the outer end of the vent hole is a threaded hole, and a screw is installed in the threaded hole. A sealing gasket is installed at one end of the screw. When injecting oil into the hydraulic oil chamber, first pull out the bolt and plunger in a pressure hole, and inject oil through the pressure hole. When injecting oil, unscrew the screw in the vent hole and remove the sealing gasket.

[0013] Furthermore, the hydraulic oil chamber formed by the base, plunger, and expansion sleeve is filled with hydraulic oil.

[0014] Furthermore, during the initial assembly, first unscrew the screws in the vent hole and remove the gasket. Connect the expansion sleeve to the base with screws, add hydraulic oil through a pressure hole on the base, tighten the screws, connect the plunger to the screws, and insert it into the pressure hole of the base.

[0015] Furthermore, in use, first install the hydraulic clamping module onto the machine tool, align and fix the hydraulic clamping module, then install the thin-walled part to be processed, inserting the part into the expansion sleeve from top to bottom along the axial direction, with the outer surface of the side wall of the part mating with the expansion sleeve; then turn the handle to compress the spring at one end of the positioning block, moving the positioning block back into the mounting hole, then pass the quick positioning module through the part, so that the lower end of the positioning shaft of the quick positioning module is inserted into the center positioning hole on the bottom surface of the base cavity, then release the handle, and under the spring thrust, the positioning block extends out of the disc and meshes with the internal teeth of the part, playing a positioning role; rotate the screws on both sides of the base, the screws push the plunger to compress the hydraulic oil and generate pressure to squeeze the expansion sleeve to clamp the part, and after clamping, the tooth cutting operation can be performed on the end face of the part.

[0016] Furthermore, after processing, loosen the screws on the base. The bolts will cause the plunger to move outward together, eliminating the clamping force on the part. Move the handle to compress the spring of the positioning block, causing the positioning block to retract into the mounting hole. At this point, the part can be removed.

[0017] Compared with the prior art, the present invention has the following technical features:

[0018] This invention relates to a thin-walled part positioning and clamping device. It employs an internal gear positioning mechanism to quickly achieve angular positioning of the workpiece. After positioning, the part is clamped using a hydraulic expansion mechanism. This avoids problems associated with traditional clamping methods, such as easy deformation of thin-walled parts, poor positioning accuracy, and cumbersome clamping processes. Using this device allows for rapid workpiece positioning and clamping, improving the reliability and machining accuracy of thin-walled parts, and ensuring a high pass rate. It has significant potential for widespread application in the machining field. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of a positioning and clamping device for thin-walled parts;

[0020] Figure 2 yes Figure 1 A sectional view;

[0021] Figure 3 yes Figure 2 Side view;

[0022] Figure 4 yes Figure 1 A sectional view;

[0023] Figure 5 This is a schematic diagram of a thin-walled part.

[0024] The components include: 1. Hydraulic clamping module, 101. Base, 102. Bolt, 103. Piston, 104. Sealing ring, 105. Expansion sleeve, 106. Positioning ring plate, 107. Cavity, 108. Hydraulic oil chamber, 109. Center positioning hole, 112. Screw, 113. Sealing ring, 114. Sealing gasket, 115. Screw, 116. Sealing ring; 2. Quick positioning module, 206. Positioning shaft, 207. Pin, 208. Handle, 209. Orientation block, 210. Pin, 211. Spring, 212. Disc, 213. Disc, 214. Mounting hole, 215. Connecting groove, 216. Through groove. Detailed Implementation

[0025] This invention, through a comprehensive analysis of the shortcomings of thin-walled part machining processes and existing clamping methods, designs a novel positioning and clamping device. This fixture employs an internal gear rapid positioning mechanism to achieve rapid and accurate angular positioning of the workpiece, with a repeatability accuracy of 0.02mm. The clamping utilizes a hydraulic expansion sleeve, improving the reliability of the fixture's positioning and clamping, ensuring the mass production of thin-walled parts, and increasing the part's pass rate. It has significant application value in the field of machining. This invention is mainly applicable to the machining of high-precision thin-walled parts, and the applicable machining methods are gear shaping or milling with internal gear angular positioning and external circle clamping.

[0026] See appendix Figures 1 to 5 This invention provides a positioning and clamping device for thin-walled parts, wherein the thin-walled part is a cylindrical part with internal teeth. The device includes a hydraulic clamping module 1 and a quick positioning module 2. The hydraulic clamping module 1 includes a base 101, and an expansion sleeve 105 is installed in the inner cavity of the base 101. The expansion sleeve 105 is a cylindrical component, and a positioning ring plate 106 is provided at the upper end of the expansion sleeve 105. Annular grooves are provided at the bottom of the positioning ring plate 106 and the lower end of the outer wall of the expansion sleeve 105. A cavity 107 is machined on the outer wall of the sleeve 105, which is located between two annular grooves. A sealing ring 113 and a sealing ring 116 are respectively installed in the two annular grooves. When the expansion sleeve 105 is assembled on the base 101, the positioning ring plate 106 of the expansion sleeve 105 is stuck on the upper edge of the inner cavity of the base. The expansion sleeve 105 is fixed on the base by screws 112. In this way, a closed hydraulic oil cavity 108 is formed between the cavity 107 between the sealing rings 113 and 116 and the inner cavity sidewall of the base 101.

[0027] The base 101 has one or more pressure holes radially opened on its side, leading to the hydraulic oil chamber 108. The outer end of each pressure hole has a stepped threaded hole. A plunger 103 is installed inside the pressure hole. The plunger 103 has two annular grooves, and a sealing ring 104 is located within each annular groove. A bolt 102 is fitted into the stepped threaded hole, and the bolt 102 is connected to the plunger 103 via a left-hand thread. Figure 2 The example has two pressure holes, which are arranged symmetrically.

[0028] The base 101 has a vent hole on its side leading to the hydraulic oil chamber 108. The outer end of the vent hole is a threaded hole, and a screw 115 is installed inside the threaded hole. A sealing gasket 114 is installed at one end of the screw 115. Figure 3 As shown; when injecting oil into the hydraulic oil chamber 108, first pull out the bolt 102 and plunger 103 in one of the pressure holes, and inject oil through the pressure hole. When injecting oil, the screw 115 in the vent hole should be unscrewed and the sealing gasket 114 should be removed.

[0029] Rapid positioning module 2, as shown Figure 4 As shown, the system includes a positioning shaft 206, with a disc 213 coaxially mounted on its lower part. The bottom of the positioning shaft 206 passes through the disc 213 and engages with a central positioning hole 109 on the bottom surface of the inner cavity of the base 101. The positioning shaft 206 is assembled in the inner cavity of the base 101. A mounting hole 214 is provided on the side of the disc 213, extending into the disc 213. A positioning block 209 is mounted in the mounting hole 214 via a spring 211. The front of the positioning block 209... The end has a toothed structure, and the spring 211 can push the front end of the positioning block 209 to the outside of the disc 213; a connecting groove 215 communicating with the mounting hole 214 is provided on the upper surface of the disc 213, and the lower end of the handle 208 is inserted into the connecting groove 215 and connected to the positioning block 209 by a pin 210; a through groove 216 is provided on the positioning shaft 206, and the handle 208 passes through the through groove 216, and the middle part of the handle 208 is installed in the through groove 216 by a pin 207.

[0030] The hydraulic oil chamber 108, which is composed of the base 101, the plunger 103, and the expansion sleeve 105, is filled with hydraulic oil.

[0031] During initial assembly, first unscrew the screw 115 in the vent hole and remove the sealing gasket 114. Connect the expansion sleeve 105 to the base 101 through the screw 112. After adding hydraulic oil through a pressure hole on the base 101, tighten the screw 115. Connect the plunger 103 to the screw 102 and insert it into the pressure hole of the base 101.

[0032] In use, first install the hydraulic clamping module 1 onto the machine tool, align and fix it, then install the thin-walled part to be processed, inserting it into the expansion sleeve 105 from top to bottom along the axial direction, with the outer surface of the side wall of the part mating with the expansion sleeve 105; then turn the handle 208 to compress the spring at one end of the positioning block 209, moving the positioning block 209 back into the mounting hole 214, then pass the quick positioning module 2 through the part, so that the lower end of the positioning shaft 206 of the quick positioning module 2 is inserted into the center positioning hole 109 on the bottom surface of the inner cavity of the base 101, then release the handle 208, and under the thrust of the spring 210, the positioning block 208 extends out of the disc 213 and meshes with the internal teeth of the part, playing a positioning role; rotate the screws 102 on both sides of the base 101, and the screws 102 push the plunger 103 to compress the hydraulic oil, generating pressure to squeeze the expansion sleeve 105 to clamp the part, and after clamping, the tooth cutting operation can be performed on the end face of the part.

[0033] After processing, loosen the screw 102 on the base 101. The bolt 102 drives the plunger 103 to move outward together, and the clamping force on the part is eliminated. Move the handle 208 to drive the positioning block 209 to compress the spring 211, so that the positioning block 209 is retracted into the mounting hole 214. At this time, the part can be taken out.

[0034] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A positioning and clamping device for thin-walled parts, characterized in that, The thin-walled part is a cylindrical part with internal teeth. The device includes a hydraulic clamping module (1) and a quick positioning module (2). The hydraulic clamping module (1) includes a base (101). The inner cavity of the base (101) is equipped with an expansion sleeve (105). A closed hydraulic oil chamber (108) is formed between the recess (107) machined on the outer wall of the expansion sleeve (105) and the inner cavity side wall of the base (101). The base (101) has one or more pressurization holes that lead to the hydraulic oil chamber (108) along the radial direction on its side, and the base (101) has vent holes that lead to the hydraulic oil chamber (108) on its side. The quick positioning module (2) includes a positioning shaft (206), with a disc (213) coaxially arranged at the lower part of the positioning shaft (206). The bottom of the positioning shaft (206) passes through the disc (213) and engages with the central positioning hole (109) on the bottom surface of the inner cavity of the base (101). The positioning shaft (206) is assembled in the inner cavity of the base (101). An installation hole (214) is provided on the side of the disc (213) and extends into the disc (213). A positioning block (209) is installed in the installation hole (214) by means of a spring (211). The positioning block (209) has a... The front end has a toothed structure, and the spring (211) pushes the front end of the positioning block (209) to the outside of the disc (213). A connecting groove (215) communicating with the mounting hole (214) is provided on the upper surface of the disc (213). The lower end of the handle (208) is inserted into the connecting groove (215) and connected to the positioning block (209) through the second pin (210). A through groove (216) is provided on the positioning shaft (206). The handle (208) passes through the through groove (216), and the middle part of the handle (208) is installed in the through groove (216) through the first pin (207).

2. The thin-walled part positioning and clamping device according to claim 1, characterized in that, The upper end of the expansion sleeve (105) is provided with a positioning ring plate (106). The bottom of the positioning ring plate (106) and the lower end of the outer wall of the expansion sleeve (105) are provided with annular grooves. The cavity (107) is machined on the outer wall of the expansion sleeve (105). The cavity (107) is located between two annular grooves. The second sealing ring (113) and the third sealing ring (116) are respectively installed in the two annular grooves. When the expansion sleeve (105) is assembled on the base (101), the positioning ring plate (106) of the expansion sleeve (105) is stuck on the upper edge of the inner cavity of the base. In this way, the cavity (107) between the second sealing ring (113) and the third sealing ring (116) and the inner cavity side wall of the base (101) form the hydraulic oil cavity (108).

3. The thin-walled part positioning and clamping device according to claim 1, characterized in that, The outer end of the pressure hole is provided with a stepped threaded hole, and a plunger (103) is installed in the pressure hole. The plunger (103) has two annular grooves, and a first sealing ring (104) is installed in the annular grooves. A bolt (102) is installed in the stepped threaded hole, and the bolt (102) is connected to the plunger (103) by a left-hand thread.

4. The thin-walled part positioning and clamping device according to claim 3, characterized in that, The outer end of the vent hole is a threaded hole, and a first screw (115) is installed in the threaded hole. A sealing gasket (114) is installed at one end of the first screw (115). When injecting oil into the hydraulic oil chamber (108), first pull out the bolt (102) and plunger (103) in one of the pressure holes, and inject oil through the pressure hole. When injecting oil, unscrew the first screw (115) in the vent hole and remove the sealing gasket (114).

5. The thin-walled part positioning and clamping device according to claim 3, characterized in that, The hydraulic oil chamber (108) formed by the base (101), plunger (103), and expansion sleeve (105) is filled with hydraulic oil.

6. The thin-walled part positioning and clamping device according to claim 4, characterized in that, During initial assembly, first unscrew the first screw (115) in the vent hole and remove the gasket (114). Connect the expansion sleeve (105) to the base (101) through the second screw (112). After adding hydraulic oil through a pressure hole on the base (101), tighten the first screw (115). Connect the plunger (103) to the bolt (102) and insert it into the pressure hole of the base (101).

7. The thin-walled part positioning and clamping device according to claim 3, characterized in that, In use, first install the hydraulic clamping module (1) onto the machine tool and align and fix the hydraulic clamping module (1). Then install the thin-walled part to be processed, insert the part into the expansion sleeve (105) from top to bottom along the axial direction, and the outer surface of the side wall of the part mates with the expansion sleeve (105). Then turn the handle (208) to compress the spring at one end of the positioning block (209), and the positioning block (209) moves back into the mounting hole (214). Then pass the quick positioning module (2) through the part to achieve quick positioning. The lower end of the positioning shaft (206) of module (2) is inserted into the center positioning hole (109) on the bottom surface of the inner cavity of the base (101). Then, the handle (208) is released, and the positioning block (209) extends out of the disc (213) under the thrust of the spring (211) and meshes with the internal teeth of the part to play a positioning role. The bolts (102) on both sides of the base (101) are rotated, and the bolts (102) push the plunger (103) to compress the hydraulic oil and generate pressure to squeeze the expansion sleeve (105) to clamp the part. After clamping, the tooth cutting operation can be performed on the end face of the part.

8. The thin-walled part positioning and clamping device according to claim 3, characterized in that, After processing, loosen the bolt (102) on the base (101). The bolt (102) drives the plunger (103) to move outward together, and the clamping force on the part is eliminated. Move the handle (208) to drive the positioning block (209) to compress the spring (211) so that the positioning block (209) is retracted into the mounting hole (214). At this time, the part can be taken out.

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