A precision, easily detachable thread clamping device

Abstract

This utility model discloses a precision, easily disassembled threaded clamping device, including a threaded mandrel and a washer. The washer is mounted on the threaded mandrel with a clearance fit. The threaded mandrel includes a clamping outer circle, a positioning ring, a locking thread, and a positioning outer circle. The contact surface between the positioning ring and the washer is provided with a first uniformly distributed relief groove and a first positioning boss surface. The outer circle of the washer is provided with uniformly distributed adjustment holes. The contact surface between the washer and the positioning ring is provided with a second uniformly distributed relief groove and a second positioning boss surface. The other side of the washer is a positioning surface that contacts the machined part. This utility model not only ensures high positioning accuracy and reliable clamping without deformation during the machining of rotating parts using smooth hole positioning and threaded locking, but also allows for easy disassembly of the parts after machining.

Description

Technical Field

[0001] This utility model relates to a machining device, and more particularly to a precision, easily detachable thread clamping device. Background Technology

[0002] In the machinery manufacturing industry, there is a typical clamping method for cylindrical rotating parts with internal threads. For example, when machining a threaded mandrel, the cylindrical rotating part with internal threads is first screwed into the mandrel with the same pitch. Utilizing the characteristic that the direction of the machining force is consistent with the direction of thread insertion, a clamping method is achieved that becomes increasingly secure as machining progresses without any other clamping devices. This typical clamping method is widely used due to its simplicity and practicality. However, this clamping method has a significant drawback: because the cylindrical rotating part becomes increasingly tighter as machining progresses, it becomes impossible to disassemble after machining. The only recourse is to use tools like pipe wrenches with sandpaper underneath (to prevent scratching the part's surface) for disassembly. While this method can remove the part, it still inevitably scratches or damages the part's surface. More importantly, if the cylindrical rotating part is thin-walled, it will deform and become unusable.

[0003] For example, a cylindrical rotating part to be machined, such as Figure 1 As shown, the material is aluminum alloy 2A12-T4. The outer diameter is φ58, and the inner dimensions of the large end (M55×0.75-7H, φ53H6, φ28H6) have been precision machined. The inner and outer dimensions of the small end have a single-sided allowance of 0.5mm. Now it is necessary to turn the inner and outer dimensions of the small end, such as φ32h6, φ23H6 and 57±0.015. The wall thickness of the tapered part of the cylindrical rotating body part is only 1.5mm, and the part has high dimensional accuracy, high coaxiality of the inner and outer circles of the large and small ends and high perpendicularity of the end face.

[0004] The aforementioned parts to be machined are thin-walled cylindrical parts with poor rigidity and high precision. It is suitable to use the pre-machined φ28H6 hole for positioning and the M55×0.75-7H thread for locking, completing the finishing of the small end. Based on the structural characteristics of the parts, a conventional threaded mandrel tool is generally used, such as... Figure 2 As shown, the tooling manufacturing and usage process is as follows: First, select tempered steel to process the semi-finished mandrel. Except for the three pre-reserved precision machining allowances at the axial positioning surface 18, locking thread 3, and positioning outer circle 4 at the end of the positioning ring 2, the other parts are machined to the required position. Second, use a machine tool self-centering chuck with three jaws to clamp the outer circle 1, and precision machine the three positioning and locking parts: axial positioning surface 18, locking thread 3, and positioning outer circle 4. Third, screw the cylindrical rotating part 6 to be machined into the conventional threaded mandrel tooling 5, as shown. Figure 3 As shown, the turning process continues until the threaded end face of the cylindrical rotating part 6 is in full contact with the axial positioning surface 18 of the conventional threaded mandrel tool 5.

[0005] like Figure 2 As shown, the axial positioning surface 18, locking thread 3, and positioning outer circle 4 on the mandrel fixture are assembled and machined only during use, thus eliminating the error of the chuck's three-jaw clamping. The positional error between the axial positioning surface 18 and the centerline of the lathe spindle rotation is extremely small. By simply controlling the clearance between the positioning outer circle 4 and the workpiece's positioning hole within a certain range (in this example, within 0.01), the positional accuracy of each finished surface of the workpiece can be easily guaranteed. Figure 3 As shown, in the conventional threaded mandrel clamping method, the three jaws of the chuck are always in a clamping state during use, only clamping the cylindrical rotating part 6 from the top and bottom, without removing the mandrel fixture 5. The mandrel fixture 5 has a right-hand thread. When the lathe spindle rotates clockwise, the force direction of the cutting tool is exactly the tightening direction of the thread. This force condition achieves natural clamping during the turning process. The greater the force on the cutting tool, the tighter the thread end face of the cylindrical rotating part 6 contacts the axial positioning surface 18 of the mandrel fixture 5, which fully guarantees the machining accuracy of the axial dimension 57±0.015. Since there is no other clamping force on the thin-walled structure, the problems of poor part rigidity and easy clamping deformation affecting part accuracy are overcome.

[0006] like Figure 4 As shown, after turning, the threaded end face of the cylindrical rotating part 6 is in very close contact with the axial positioning surface 18 of the mandrel tool 5, the thread preload is large, and the surface of the part is smooth and it is a thin-walled aluminum part. Therefore, it is very difficult to remove the cylindrical rotating part 6 from the threaded mandrel tool 5. Even if tools such as pipe wrenches 9 are used with sandpaper 8 for disassembly, it is inevitable to scratch or damage the surface of the part, or cause the part to be deformed by extrusion during disassembly, which often leads to the scrapping of the part. Utility Model Content

[0007] To maximize the high precision of conventional threaded mandrels while addressing the challenge of disassembling rotating parts after machining, this invention provides a precision, easily disassembled threaded clamping device. This device not only ensures high positioning accuracy and reliable, deformation-free clamping for rotating parts using open-hole positioning and threaded locking, but also facilitates easy disassembly after machining.

[0008] This utility model adopts the following technical solution: a precision easy-to-disassemble threaded clamping device, including a threaded mandrel and a washer, wherein the washer is installed on the threaded mandrel with a clearance fit; the threaded mandrel includes a clamping outer circle, a positioning ring, a locking thread, and a positioning outer circle; the contact surface between the positioning ring and the washer is provided with a uniformly distributed relief groove and a positioning boss surface, and the relief groove and the positioning boss surface are spaced apart; the outer circle of the washer is provided with uniformly distributed adjustment holes; the contact surface between the washer and the positioning ring is provided with a uniformly distributed relief groove and a positioning boss surface, and the relief groove and the positioning boss surface are spaced apart; the other side of the washer is a positioning surface that contacts the machined part.

[0009] Furthermore, both the first relief groove and the first positioning boss are fan-shaped, and the fan-shaped area of ​​the first relief groove is larger than the fan-shaped area of ​​the first positioning boss.

[0010] Furthermore, both the second relief groove and the second positioning boss are fan-shaped, and the fan-shaped area of ​​the second relief groove is larger than the fan-shaped area of ​​the second positioning boss.

[0011] Furthermore, the relief groove one at the end of the positioning ring is the same size as the relief groove two on the washer, and the two have the same number.

[0012] Furthermore, the positioning boss surface one at the end of the positioning ring and the positioning boss surface two on the washer are the same size and have the same number.

[0013] This utility model has the following beneficial effects: when turning precision rotating thin-walled parts used for hole positioning and thread locking, it can ensure high positioning accuracy and reliable clamping without deformation, and can easily disassemble the parts without damaging them. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the structure of the part to be processed; Figure 2 This is a structural diagram of a conventional threaded mandrel tool. Figure 3 A schematic diagram of part clamping for a conventional threaded mandrel tool; Figure 4 A schematic diagram illustrating the use of pipe wrenches to disassemble parts using a conventional threaded mandrel tool; Figure 5 This is a schematic diagram of the structure of the threaded mandrel of this utility model; Figure 6 This is a first-view structural diagram of the gasket of this utility model; Figure 7 This is a second-view structural schematic diagram of the gasket of this utility model; Figure 8 This is a schematic diagram of the machining state of the present invention and the parts after clamping; Figure 9 for Figure 8 A cross-sectional view of the machining process; Figure 10 This is a schematic diagram showing the disassembled state of the present invention and its parts; Figure 11 for Figure 10 A cross-sectional view of the disassembled state.

[0015] In the diagram: 1. Clamping outer circle, 2. Locating ring, 3. Locking thread, 4. Locating outer circle, 5. Conventional threaded mandrel tooling, 6. Cylindrical rotating part, 7. Chuck three jaws, 8. Sandpaper, 9. Pipe wrench, 10. Threaded mandrel, 11. Washer, 12. Relief groove one, 13. Locating boss surface one, 14. Adjusting hole, 15. Relief groove two, 16. Locating boss surface two, 17. Locating surface, 18. Axial locating surface. Detailed Implementation

[0016] To make the objectives, technical solutions, and advantages of this utility model clearer, the technical solutions of this utility model will be clearly and completely described below in conjunction with specific embodiments and corresponding drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments.

[0017] like Figure 5-11 As shown, this utility model embodiment provides a precision easy-to-disassemble thread clamping device, including a threaded mandrel 10 and an easy-to-disassemble washer 11. The threaded mandrel 10 is the basic component of the clamping device, and the washer 11 mainly plays the role of transmitting and unloading the thread clamping force. The washer 11 is installed on the threaded mandrel 10 with a clearance fit.

[0018] like Figure 5 As shown, the threaded mandrel 10 has a similar structure to the existing conventional threaded mandrel tooling 5, including a clamping outer circle 1, a positioning ring 2, a locking thread 3, and a positioning outer circle 4. The difference is that the positioning ring 2 and the washer 11 are provided with uniformly distributed relief grooves 12 and positioning boss surfaces 13, and the relief grooves 12 and positioning boss surfaces 13 are distributed at intervals. The positioning boss surfaces 13 play a positioning role. Both the relief grooves 12 and the positioning boss surfaces 13 are fan-shaped, and the fan-shaped area of ​​the relief grooves 12 is larger than the fan-shaped area of ​​the positioning boss surfaces 13.

[0019] like Figure 6 and 7As shown, the outer circumference of the washer 11 is provided with evenly distributed adjustment holes 14. Even in the locked state, a hook wrench can be inserted into the adjustment holes 14 to easily rotate the washer 11 around the threaded spindle 10. The contact surface between the washer 11 and the positioning ring 2 is provided with evenly distributed relief grooves 15 and positioning boss surfaces 16, and the relief grooves 15 and positioning boss surfaces 16 are spaced apart. The positioning boss surfaces 16 play a positioning role. Both the relief grooves 15 and positioning boss surfaces 16 are fan-shaped, and the fan-shaped area of ​​the relief grooves 15 is larger than that of the positioning boss surfaces 16. The other side of the washer 11 is the positioning surface 17 that contacts the machined part.

[0020] In this embodiment, the relief groove 12 at the end of the positioning ring 2 is the same size as the relief groove 15 on the washer 11, and the two have the same number; the positioning boss surface 13 at the end of the positioning ring 2 is the same size as the positioning boss surface 16 on the washer 11, and the two have the same number.

[0021] The manufacturing process of this utility model is as follows: 1. Before machining the part, the threaded mandrel 10 of the clamping device needs to be prepared in advance, such as... Figure 5 As shown, semi-finished product processing is carried out. Except for the three reserved precision machining allowances at the locating boss surface 13 at the end of the locating ring 2, the locking thread 3, and the locating outer circle 4, the other parts are processed to the required condition. At the same time, all processing of the washer 11 is completed, such as... Figure 6 and Figure 7 As shown, the positioning surface 17 and the positioning boss surface 16 are ground to ensure that they have sufficient parallelism accuracy.

[0022] 2. When machining the parts, first use the machine tool's self-centering chuck to clamp the outer diameter 1 of the threaded mandrel 10 with three jaws, and then precision machine the three positioning and locking parts: the positioning boss surface 13, the locking thread 3, and the positioning outer diameter 4. Then install the washer 11, as follows. Figure 8 As shown, the mating shaft portion of the washer 11 and the threaded mandrel 10 has a clearance fit, allowing for relative free rotation and axial movement. During assembly, the locating boss surface 13 of the threaded mandrel 10 is aligned and in contact with the locating boss surface 16 of the washer 11, and the parts are locked. Finally, the cylindrical rotating part 6 is screwed into the threaded mandrel 10 until the threaded end face of the cylindrical rotating part 6 is in full contact with the locating surface 17 of the washer 11, and then machining is performed.

[0023] The working principle of this utility model: like Figure 8 and Figure 9As shown, when the clamping device is in use, the threaded mandrel 10 is always clamped in the three-jaw chuck of the machine tool, and only the part 6 is moved up and down without removing the threaded mandrel 10. The positioning boss surface 13, locking thread 3, and positioning outer circle 4 of the threaded mandrel 10 are all fixed on the machine tool chuck before being machined. This eliminates the error of the three-jaw clamping. The positional error between the positioning boss surface 13 and the rotation axis of the machine tool spindle is extremely small. As long as the clearance between the positioning outer circle 4 and the positioning hole of the part 6 is controlled within a certain range (in this example, it can be controlled within 0.01), the positional accuracy of each finished surface of the part 6 can be easily guaranteed. The threaded mandrel 10 has a right-hand thread. When the machine tool spindle rotates clockwise, the direction of the cutting force of the cutting tool is exactly the tightening direction of the thread. This force condition achieves natural clamping during the turning process. The greater the force on the cutting tool, the tighter the threaded end face of the cylindrical rotating part 6 contacts the positioning surface 17 of the washer 11. Because the parallelism between the positioning surface 17 of the intermediate transition part—the washer 11—and the positioning boss surface 16 is very small (within 0.008 in this embodiment), it can fully guarantee the dimensional accuracy of each axis in this embodiment, such as the machining accuracy of 57±0.015. Since there is no other clamping force on the thin-walled structure of part 6, the problem of poor rigidity and easy deformation of part 6 affecting the accuracy of the part is overcome.

[0024] like Figure 10 and Figure 11 As shown, after the part is turned, insert the hook wrench into the adjustment hole 14 of the washer 11 and rotate the washer 11 so that the positioning boss surface 16 of the washer 11 falls into the relief groove 12 of the threaded mandrel 10, resulting in a gap between the threaded end face of the part 6 and the positioning surface 17 of the washer 11. At this time, the threaded end face of the cylindrical rotating body part 6 is not under force, and the cylindrical rotating body part 6 can be easily disassembled, thus perfectly solving the problem of difficult disassembly of parts by conventional threaded mandrel tooling.

[0025] The above description is merely an embodiment of this utility model and is not intended to limit the scope of this utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principle of this utility model should be included within the scope of the claims of this utility model.

Claims

1. A precision, easily detachable threaded clamping device, characterized in that, The device includes a threaded mandrel (10) and a washer (11). The washer (11) is installed on the threaded mandrel (10) with a clearance fit. The threaded mandrel (10) includes a clamping outer circle (1), a positioning ring (2), a locking thread (3), and a positioning outer circle (4). The contact surface between the positioning ring (2) and the washer (11) is provided with a uniformly distributed relief groove (12) and a positioning boss surface (13), and the relief groove (12) and the positioning boss surface (13) are spaced apart. The outer circle of the washer (11) is provided with a uniformly distributed adjustment hole (14). The contact surface between the washer (11) and the positioning ring (2) is provided with a uniformly distributed relief groove (15) and a positioning boss surface (16), and the relief groove (15) and the positioning boss surface (16) are spaced apart. The other side of the washer (11) is a positioning surface (17) that contacts the machined part.

2. The precision easily detachable thread clamping device according to claim 1, characterized in that, Both the first relief groove (12) and the first positioning boss (13) are fan-shaped, and the fan-shaped area of ​​the first relief groove (12) is larger than the fan-shaped area of ​​the first positioning boss (13).

3. The precision easily detachable threaded clamping device according to claim 2, characterized in that, Both the second relief groove (15) and the second positioning boss (16) are fan-shaped, and the fan-shaped area of ​​the second relief groove (15) is larger than the fan-shaped area of ​​the second positioning boss (16).

4. The precision easily detachable thread clamping device according to claim 3, characterized in that, The relief groove 1 (12) at the end of the positioning ring (2) is the same size as the relief groove 2 (15) on the washer (11), and the two have the same number.

5. A precision easily detachable thread clamping device according to claim 4, characterized in that, The positioning boss surface one (13) at the end of the positioning ring (2) and the positioning boss surface two (16) on the washer (11) are the same size and have the same number.

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