Special-shaped shaft clamp tool and manufacturing method thereof and method for machining special-shaped shaft

Abstract

This invention provides a fixture for irregularly shaped shafts, its manufacturing method, and a method for machining irregularly shaped shafts. The fixture includes a positioning shaft assembly and a bushing. The positioning shaft assembly includes a first positioning shaft and a second positioning shaft connected together. One end of the second positioning shaft passes through a hole in the irregularly shaped shaft and is detachably connected to the bushing. A clamping space for holding the irregularly shaped shaft is formed between the inner surface of the first positioning shaft and the inner surface of the bushing. Machine tool ejector holes are respectively provided on the outer end face of the first positioning shaft and the outer end face of the bushing. The central axes of the two machine tool ejector holes located on the outer end faces of the first and bushings coincide. This central axis intersects the central axis of the second positioning shaft at the center of the hole in the irregularly shaped shaft, forming an acute angle. Twice the angle value is complementary to the bending angle value of the irregularly shaped shaft. This fixture simplifies the machining and forming steps of irregularly shaped bent shaft workpieces, improves the positioning accuracy during machining, increases machining efficiency, and reduces the scrap rate of the workpiece.

Description

Technical Field

[0001] This invention relates to the field of auxiliary clamping equipment, and more specifically, to a fixture for irregularly shaped shafts, a method for manufacturing the fixture, and a method for machining irregularly shaped shafts. Background Technology

[0002] Turning and grinding the outer diameter of irregularly shaped shaft parts are quite difficult, resulting in a high scrap rate. For irregularly shaped parts, machining generally requires auxiliary tooling. Currently, the design and manufacturing scheme is often implemented with one tooling per product, which has significant advantages, achieving specialization of tooling fixtures.

[0003] For example, patent application CN115781338A discloses a clamping fixture and method for irregularly shaped parts, including a fixed base plate, a machinable positioning block, a machinable positioning shaft, and a cam-side clamping block. The fixed base plate has multiple rows of threaded holes arranged in an array at its upper end, with positioning grooves around the upper periphery of the threaded holes. The machinable positioning block includes a first machinable positioning block and a second machinable positioning block. The machinable positioning shaft includes a first pin at its lower end and a machinable frustum at its upper end. The cam-side clamping block includes a second pin at its lower end and a polygonal clamping block at its upper end. Designers first arrange the positioning blocks and cam-side clamping block according to the characteristics of the part being processed, and then carve out the contour positioning groove, surface, etc. Production personnel can then process the general-purpose fixture according to the arrangement diagram. This clamping fixture for irregularly shaped parts can effectively save on tooling materials and manufacturing costs, and improve production efficiency. However, the clamping fixture for this irregular part requires pre-cutting out contour positioning grooves and surfaces, and the processing steps are relatively complicated, making it unsuitable for machining irregular shaft parts with symmetrical structures. Summary of the Invention

[0004] In order to simplify the machining and forming steps of irregular shaft parts with symmetrical structure, improve the positioning accuracy during the machining process, improve the machining efficiency, and reduce the scrap rate of workpieces, the technical solution adopted by the present invention is: an irregular shaft fixture, including a positioning shaft assembly and a bushing, wherein the positioning shaft assembly includes a first positioning shaft and a second positioning shaft connected to each other; One end of the second positioning shaft passes through the irregular shaft hole and is detachably connected to the bushing. A clamping space for clamping the irregular shaft is formed between the inner side of the first positioning shaft and the inner side of the bushing. Machine tool ejector pin holes are respectively formed on the outer end face of the first positioning shaft and the outer end face of the bushing. The central axes of the two machine tool ejector pin holes located on the outer end face of the first positioning shaft and the outer end face of the bushing coincide. The central axis intersects the central axis of the second positioning shaft at the center of the irregular shaft hole and the included angle formed is an acute angle. Twice the included angle value is complementary to the bending angle value of the irregular shaft.

[0005] Based on the above, in order to prevent misalignment and shaking of the irregular shaft workpiece during processing, a first positioning pin hole is provided along the radial direction of the second positioning axis for cooperating with the part limiting groove at one end of the irregular shaft, and a second positioning pin hole is provided along the inner axial direction of the bushing for cooperating with the part limiting groove at the other end of the irregular shaft. Positioning pins are respectively provided in the first positioning pin hole and the second positioning pin hole.

[0006] That is, the locating pin on the second locating shaft can be used to engage with the part limiting groove on one end of the irregular shaft to position the irregular shaft by circumferential displacement. The locating pin on the bushing can be used to engage with the part limiting groove on the other end of the irregular shaft to position the bushing by circumferential displacement.

[0007] Based on the above, in order to improve the connection between the second positioning shaft and the bushing and to facilitate installation and positioning, a shaft mounting hole is provided at the inner end of the bushing, and one end of the second positioning shaft is clearance-fitted with the shaft mounting hole and connected to the bushing by a fastening screw.

[0008] During the actual machining process, the diameter of one end of the second positioning shaft can be reduced, and the diameter of the shaft mounting hole can be designed to be smaller than the diameter of the second positioning shaft.

[0009] Based on the above, in order to facilitate the machining of the machine tool ejector pin hole, and to facilitate rotation operation and determine the included angle between the central axis and the central axis of the second positioning axis, a process hole is provided along the radial direction of the second positioning axis, and the process hole passes through the center of the irregular shaft hole.

[0010] Specifically, in order to facilitate turning during the machining of the outer diameter of the first positioning shaft and to prevent the cutting tool from colliding with the irregular shaft simulation sleeve fitted on the second positioning shaft, a clearance groove is provided at the inner end of the first positioning shaft. In actual machining, the clearance groove is formed by pre-machining a stepped surface on the contact surface between the first and second positioning shafts, and then forming it during the subsequent machining of the outer diameter of the first positioning shaft.

[0011] This invention also provides a method for manufacturing an irregularly shaped shaft fixture, comprising the following steps: The irregular shaft simulated sleeve is machined with reference to the shaft hole diameter and horizontal projection length of the irregular shaft. The blank of the irregular shaft simulated sleeve is machined so that the inner diameter of the hollow straight cylinder and the length of the blank are the same as the shaft hole diameter and horizontal projection length of the irregular shaft, respectively. A simulated positioning hole is machined along the radial direction of the irregular shaft simulated sleeve blank, and the simulated positioning hole passes through the center of the hollow straight cylinder of the irregular shaft simulated sleeve blank. The pre-machined positioning shaft assembly is used to machine a stepped shaft with a second positioning shaft at the inner end; A bushing is machined to be detachably connected to one end of the second positioning shaft. The assembly involves passing one end of the second positioning shaft through the irregular shaft simulation sleeve and detachably connecting it to the bushing to form a temporary assembly tooling. The temporary assembly fixture is placed horizontally with the machine tool ejector pin hole as the horizontal rotation axis. The temporary assembly fixture is rotated around the center axis of the simulated positioning hole. After it is rotated into place, it is fixed. The machine tool ejector pin hole is machined along the same horizontal axis on the outer end face of the bushing and the outer end face of the stepped shaft, respectively. The horizontal axis intersects the center axis of the second positioning axis at the center of the hollow straight cylinder of the irregular shaft simulated sleeve blank. The rotation angle value of the temporary assembly fixture is twice that of the bending angle value of the irregular shaft. The machining positioning shaft assembly is respectively pressed against the machine tool ejector pin holes located on the outer end face of the bushing and the outer end face of the stepped shaft, and the outer end of the stepped shaft is machined into a first positioning shaft, so that the central axis of the first positioning shaft coincides with the central axis of the two machine tool ejector pin holes.

[0012] In this case, the center of the hollow straight cylinder in the shaped shaft simulation sleeve blank is at the same position as the center of the shaped shaft hole, and the center of the simulation positioning hole is at the same position as the center of the shaped shaft hole.

[0013] Based on the above, in order to limit the irregular shaft simulation sleeve and to position the irregular shaft simulation sleeve and the irregular shaft using positioning pins to prevent movement during processing, the step of processing the irregular shaft simulation sleeve further includes: referring to the position of the part limiting grooves at both ends of the irregular shaft, machining contour limiting grooves radially on the side walls at both ends of the irregular shaft simulation sleeve blank. The pre-processing positioning shaft assembly step further includes: referring to the position of the contour limiting groove at one end of the irregular shaft simulated sleeve blank, machining a first positioning pin hole along the radial direction of the second positioning shaft; The machining bushing step further includes: referring to the position of the contour limiting groove at the other end of the irregular shaft simulated sleeve blank, machining a second positioning pin hole along the inner axis of the bushing.

[0014] Based on the above, in order to facilitate the installation and positioning between the second positioning shaft and the bushing, the bushing processing step further includes: machining a shaft mounting hole that is clearance-fitted with one end of the second positioning shaft and a bolt hole for connecting one end of the second positioning shaft in sequence from the inner side to the outer end of the bushing along the central axis direction of the bushing; The pre-processing of the positioning shaft assembly further includes: machining a threaded hole along the central axis of one end of the second positioning shaft to match the bolt hole.

[0015] Based on the above, the assembly step further includes machining a process hole in the radial direction of the second positioning axis with reference to the position of the simulated positioning hole, the process hole passing through the center of the simulated positioning hole.

[0016] Specifically, for ease of operation, after machining the process hole, the step of machining the machine tool ejector pin hole can be as follows: On a reference platform, use a V-block to horizontally support the outer circle of the irregular shaft simulating the sleeve of the temporary assembly fixture. Ensure the outer circle of the irregular shaft simulating the sleeve is level, determine the height from the center of the process hole to the reference platform, then rotate the temporary assembly fixture around the process hole as the rotation center, adjusting the support height of the temporary assembly fixture to ensure the height from the center of the process hole to the reference platform remains constant, and clamp and fix the temporary assembly fixture. Then, machine tool ejector pin holes are machined along the same horizontal axis at the outer end of the bushing and the other end of the round bar, ensuring that this horizontal axis intersects the central axis of the second positioning axis at the center of the process hole. The rotation angle value of the temporary assembly fixture is twice the bending angle value at both ends of the irregular shaft.

[0017] That is, when installing and machining the irregular shaft in the later stage, the center of the shaft hole of the irregular shaft coincides with the center of the process hole.

[0018] When machining the machine tool ejector hole along the same horizontal axis at the outer end of the bushing and the other end of the round bar, in order to make the horizontal axis intersect the center axis of the second positioning axis at the center of the process hole, a pair of machine tool ejectors can be used in advance to find the center of the outer end face of the cylindrical bushing and the center of the outer end face of the positioning axis assembly, and keep the position of the machine tool ejectors unchanged. Then, after rotating the temporary assembly fixture by a certain angle, the pair of machine tool ejectors are moved horizontally again. At this time, the point where the pair of machine tool ejectors contacts the outer end face of the cylindrical bushing and the point where they contact the outer end face of the positioning axis assembly are the machining center points of the machine tool ejector hole.

[0019] Alternatively, the positions of the two machine tool ejector pin holes can be found using a fitter's scribing method. First, draw the diameter passing through the center point on the outer end face of the cylindrical bushing and the outer end face of the positioning shaft assembly, respectively, in the vertical direction. Then, after rotating the temporary assembly fixture by a certain angle, using the height from the center of the process hole to the reference platform as the standard, draw corresponding height lines on the outer end faces of the cylindrical bushing and the positioning shaft assembly, respectively. The intersection of the height lines and the diameters is the machining center point of the two machine tool ejector pin holes.

[0020] The present invention also provides a method for machining irregular shafts using the above-mentioned irregular shaft fixture, comprising the following steps: In one assembly process, one end of the second positioning shaft is passed through the shaft hole of the irregular shaft blank and detachably connected to the bushing, so that the irregular shaft blank is clamped between the inner side of the first positioning shaft and the inner side of the bushing. Then, the machine tool ejector pin is used to lift the machine tool ejector pin holes located on the outer end face of the first positioning shaft and the outer end face of the bushing respectively, and the outer circle of one end of the irregular shaft blank is machined. The bushing and the second positioning shaft are disassembled for secondary assembly processing to remove the irregular shaft blank from the second positioning shaft. Then, the left and right ends of the irregular shaft blank are interchanged, and the assembly processing steps are repeated once. The outer circle of the other end of the irregular shaft blank is machined.

[0021] Based on the above, in order to prevent the irregular shaft blank from moving during the processing, before turning the outer circle of one end of the irregular shaft blank, the part limiting groove of one end of the irregular shaft blank is aligned with the first positioning pin hole on the second positioning shaft, and the part limiting groove of the other end of the irregular shaft blank is aligned with the second positioning pin hole inside the bushing. Then, positioning pins are installed in the first positioning pin hole and the second positioning pin hole respectively.

[0022] The irregularly shaped shaft in this invention comprises a left-sloping stepped shaft, a right-sloping stepped shaft, and a central partition. The left and right-sloping stepped shafts are respectively connected to both sides of the central partition. A transversely penetrating shaft hole is formed inside the left-sloping stepped shaft, the right-sloping stepped shaft, and the central partition. The central partition is a near-circular plate, thicker at the top and thinner at the bottom, with a straight edge at the bottom. The bending angle at both ends of the irregularly shaped shaft refers to the angle between the axis of the left-sloping stepped shaft and the axis of the right-sloping stepped shaft. Part limiting grooves are radially distributed at both ends of the left-sloping stepped shaft and the right-sloping stepped shaft.

[0023] Specifically, the center of the irregular shaft hole is located at the center point on the central axis of the irregular shaft hole. The center of the hollow straight cylinder of the irregular shaft simulated sleeve blank is located at the center point on the central axis of the hollow straight cylinder of the irregular shaft simulated sleeve blank.

[0024] This invention possesses significant substantive features and remarkable advancements compared to existing technologies. Specifically, the irregular shaft fixture, its manufacturing method, and the method for machining irregular shafts provided by this invention, based on the symmetrical structure and the inherent characteristics of the irregular shaft part—its left and right inclined stepped shafts—are designed as a positioning shaft assembly and a bushing connected by fastening screws. This facilitates clamping and the turning and forming of the irregular shaft part. Furthermore, considering the internal shaft hole of the irregular shaft part, and the fact that the centerline of the shaft hole deviates from the center of the end face of the irregular shaft part, the positioning shaft assembly is designed as a three-section structure. A machine tool ejector pin hole is opened at one end of the first section to ensure that the inclined stepped shaft of the irregular shaft part coincides with the machining center axis of the machine tool during machining. The platform between the second and first sections forms a positioning step surface for positioning the irregular shaft part. Simultaneously, the diameter of one end of the second positioning shaft is reduced to form the third section, which is inserted into the bushing to effectively position the other end of the irregular shaft part.

[0025] Meanwhile, machine tool ejector pin holes are provided on the positioning axis assembly to ensure the machining position of the irregular shaft parts. Simulated workpieces are used in advance to assist in machining the machine tool ejector pin holes on the positioning axis and bushing, thereby improving the machining accuracy and consistency of the irregular shaft parts.

[0026] Therefore, the fixture and tooling for irregular shafts, as well as the method for manufacturing and machining irregular shafts, simplify the machining and forming steps of irregular shaft parts with symmetrical structures, improve the positioning accuracy during machining, increase machining efficiency, and reduce the scrap rate of workpieces. Attached Figure Description

[0027] Figure 1 , Figure 2 and Figure 3 This is a schematic diagram of the structure of an irregularly shaped shaft part.

[0028] Figure 4 and Figure 5 This is a schematic diagram of the irregular shaft fixture and irregular shaft parts assembly structure provided by the present invention.

[0029] Figure 6 This is a schematic diagram of the cross-sectional structure of the irregular shaft fixture and irregular shaft parts assembly provided by the present invention.

[0030] Figure 7 This is a schematic diagram of the overall structure of the positioning shaft assembly in the irregular shaft fixture provided by the present invention.

[0031] Figure 8 This is a cross-sectional structural diagram of the positioning shaft assembly in the irregular shaft fixture provided by the present invention.

[0032] Figure 9 This is a schematic diagram of the irregular shaft fixture and irregular shaft simulation sleeve assembly structure provided by the present invention.

[0033] Figure 10 This is a schematic diagram of the blank structure of the positioning shaft assembly in the irregular shaft fixture provided by the present invention.

[0034] Figure 11 and Figure 12 This is a schematic diagram of the assembly structure of the positioning shaft assembly blank and the irregular shaft simulation sleeve in the irregular shaft fixture tooling provided by the present invention.

[0035] Figure 13 This is a schematic diagram of the assembly structure of the positioning shaft assembly and the simulated sleeve of the irregular shaft in the irregular shaft fixture provided by the present invention.

[0036] In the diagram: 1. Middle partition; 2. Left inclined stepped shaft; 3. Right inclined stepped shaft; 4. Shaft hole; 5. Part limiting groove; 6. Edge; 7. First positioning shaft; 8. First machine tool ejector pin hole; 9. Relief groove; 10. Second positioning shaft; 11. Process hole; 12. First positioning pin hole; 13. Positioning step surface; 14. Second machine tool ejector pin hole; 15. Bushing; 16. Fastening screw; 17. Second positioning pin hole; 18. Shaft mounting hole; 19. Screw assembly hole; 20. Threaded hole; 21. Irregular shaft simulation sleeve; 22. Simulated positioning hole; 23. Positioning pin. Detailed Implementation

[0037] The technical solution of the present invention will be further described in detail below through specific embodiments.

[0038] Example 1 This embodiment provides a fixture for irregularly shaped shafts, such as... Figure 6 , Figure 7 , Figure 8 , Figure 9 As shown, it includes a positioning shaft assembly and a bushing 15. The positioning shaft assembly includes a first positioning shaft 7 and a second positioning shaft 10 connected to each other.

[0039] One end of the second positioning shaft 10 passes through the shaft hole 4 of the irregular shaft and is detachably connected to the bushing 15. A clamping space for clamping the irregular shaft is formed between the inner side of the first positioning shaft 7 and the inner side of the bushing 15.

[0040] Machine tool ejector pin holes are respectively formed on the outer end face of the first positioning shaft 7 and the outer end face of the bushing 15. The central axes of the two machine tool ejector pin holes located on the outer end faces of the first positioning shaft and the bushing 15 coincide. This central axis intersects the central axis of the second positioning shaft 10 at the center of the irregular shaft hole, and the included angle formed is an acute angle. Twice the value of this included angle is complementary to the bending angle value of the irregular shaft.

[0041] For ease of distinction, the two machine tool ejector pin holes are respectively designated as the first machine tool ejector pin hole 8 and the second machine tool ejector pin hole 14. The first positioning axis and the second positioning axis table form the positioning step surface 13 for positioning irregularly shaped shaft parts.

[0042] Specifically, such as Figure 1 , Figure 2 , Figure 3 and Figure 6 As shown, the angle between the central axis of the two machine tool ejector pin holes and the axis of the second positioning axis is denoted as angle α. The bending angle at both ends of the irregular shaft is denoted as angle β. Specifically, the bending angle at both ends of the irregular shaft refers to the angle between the axis of the left inclined stepped shaft 2 and the axis of the right inclined stepped shaft 3.

[0043] Specifically, the irregularly shaped shaft part structure processed in this embodiment is as follows: Figure 1 , Figure 2 and Figure 3 As shown, it specifically includes a left-sloping stepped shaft 2, a right-sloping stepped shaft 3, and a middle partition plate 1. The left-sloping stepped shaft 2 and the right-sloping stepped shaft 3 are respectively connected to both sides of the middle partition plate 3. The left-sloping stepped shaft 2, the right-sloping stepped shaft 3, and the middle partition plate 1 have transversely penetrating shaft holes 4 inside. The middle partition plate 1 is a roughly circular plate that is thicker at the top and thinner at the bottom, and the lower part of the middle partition plate 1 forms a straight edge 6. The left-sloping stepped shaft 2 and the right-sloping stepped shaft 3 have radially distributed part limiting grooves 5 at both ends.

[0044] Example 2 This embodiment provides a fixture for irregularly shaped shafts. The main difference between this embodiment and Embodiment 1 is that, in this embodiment: Figure 1 , Figure 2 , Figure 3 , Figure 7 , Figure 8 and Figure 11 In order to prevent misalignment and shaking of the irregular shaft workpiece during processing, a first positioning pin hole 12 is provided along the radial direction of the second positioning shaft 10 for cooperating with the part limiting groove 5 at one end of the irregular shaft.

[0045] A second locating pin hole 17 is provided along the inner axial direction of the bushing 15 for engaging with the part limiting groove 5 at the other end of the irregular shaft. Locating pins 23 are respectively provided in the first locating pin hole 12 and the second locating pin hole 17.

[0046] That is, the locating pin on the second locating shaft can be used to engage with the part limiting groove on one end of the irregular shaft to position the irregular shaft by circumferential displacement. The locating pin on the bushing can be used to engage with the part limiting groove on the other end of the irregular shaft to position the bushing by circumferential displacement.

[0047] Example 3 This embodiment provides a fixture for irregularly shaped shafts. The main difference between this embodiment and Embodiment 1 is that, in this embodiment: Figure 6 , Figure 8 and Figure 9 As shown, in order to facilitate the installation and positioning between the second positioning shaft 10 and the bushing 15, the inner end of the bushing 15 is provided with a shaft mounting hole 18 and a screw assembly hole 19, and the outer end of the second positioning shaft 10 is provided with a threaded hole 20. One end of the second positioning shaft 10 is inserted into the shaft mounting hole 18 and connected to the bushing 15 by a fastening screw 16.

[0048] Example 4 This embodiment provides a non-circular shaft fixture. The main difference from Embodiment 1 is that, to facilitate the machining of the machine tool ejector pin hole and to facilitate rotational operation and determining the angle between the central axis and the central axis of the second positioning axis, this embodiment includes a process hole 11 formed radially along the second positioning axis 10. The process hole 11 passes through the center of the shaft hole 4 of the non-circular shaft. This process hole is subsequently formed by contour machining based on the simulated positioning hole 22 on the non-circular shaft simulation sleeve 21 fitted onto the second positioning axis.

[0049] Specifically, in order to facilitate turning during the machining of the outer diameter of the first positioning shaft and to prevent the cutting tool from colliding with the irregular shaft simulation sleeve fitted on the second positioning shaft, a relief groove 9 is provided at the inner end of the first positioning shaft 7. In actual machining, the relief groove 9 is formed by pre-machining a stepped surface on the contact surface between the first and second positioning shafts, and then forming it during the subsequent machining of the outer diameter of the first positioning shaft.

[0050] Example 5 This embodiment provides a method for manufacturing the irregular shaft fixture described in Embodiment 1, such as... Figure 10 , Figure 11 , Figure 12 and Figure 13 As shown, it includes the following steps: A hollow bar stock is provided for machining a non-circular shaft simulated sleeve. Referring to the shaft hole diameter and horizontal projection length of the non-circular shaft, a non-circular shaft simulated sleeve blank is machined such that the inner diameter of the hollow straight cylinder and the length of the blank are the same as the shaft hole diameter and horizontal projection length of the non-circular shaft, respectively. A simulated positioning hole is machined along the radial direction of the non-circular shaft simulated sleeve blank, and the simulated positioning hole passes through the center of the central axis of the non-circular shaft simulated sleeve blank. The pre-machined positioning shaft assembly is used to machine a stepped shaft with a second positioning shaft at the inner end; A bushing is machined to be detachably connected to one end of the second positioning shaft. The assembly involves passing one end of the second positioning shaft through the irregular shaft simulation sleeve and detachably connecting it to the bushing to form a temporary assembly tooling. The temporary assembly fixture is placed horizontally with the machine tool ejector pin hole as the horizontal rotation axis. The temporary assembly fixture is rotated around the center axis of the simulated positioning hole. After it is rotated into place, it is fixed. The machine tool ejector pin hole is machined along the same horizontal axis on the outer end face of the bushing and the outer end face of the stepped shaft, respectively. The horizontal axis intersects the center axis of the second positioning axis at the center of the hollow straight cylinder of the irregular shaft simulated sleeve blank. The rotation angle value of the temporary assembly fixture is twice that of the bending angle value of the irregular shaft. The machining positioning shaft assembly is respectively pressed against the machine tool ejector pin holes located on the outer end face of the bushing and the outer end face of the stepped shaft, and the outer end of the stepped shaft is machined into a first positioning shaft, so that the central axis of the first positioning shaft coincides with the central axis of the two machine tool ejector pin holes.

[0051] In this case, the center of the hollow straight cylinder in the shaped shaft simulation sleeve blank is at the same position as the center of the shaped shaft hole, and the center of the simulation positioning hole is at the same position as the center of the shaped shaft hole.

[0052] Specifically, in this embodiment, when machining the machine tool ejector hole along the same horizontal axis at the outer end of the bushing and the other end of the round bar, in order to achieve the intersection of the horizontal axis with the central axis of the second positioning axis at the center of the process hole, a pair of machine tool ejectors can be used in advance to find the center of the outer end face of the cylindrical bushing and the center of the outer end face of the positioning axis assembly, and keep the position of the machine tool ejectors unchanged. Then, after rotating the temporary assembly fixture by a certain angle, the pair of machine tool ejectors are moved horizontally again. At this time, the point where the pair of machine tool ejectors contacts the outer end face of the cylindrical bushing and the point where they contact the outer end face of the positioning axis assembly are the machining center points of the machine tool ejector hole.

[0053] Alternatively, in other embodiments, the positions of the two machine tool ejector pin holes can be found using a fitter's scribing method. Specifically, first, draw the diameter passing through the center point on the outer end face of the cylindrical bushing and the outer end face of the positioning shaft assembly, respectively, in the vertical direction. Then, after rotating the temporary assembly fixture by a certain angle, using the height from the center of the process hole to the reference platform as a standard, draw corresponding height lines on the outer end faces of the cylindrical bushing and the positioning shaft assembly, respectively. The intersection of the height lines and the diameters is the machining center point of the two machine tool ejector pin holes.

[0054] Example 6 This embodiment provides a method for manufacturing a fixture for an irregular shaft. The main difference from Embodiment 5 is that, in order to limit the irregular shaft simulation sleeve and to position the irregular shaft simulation sleeve and the irregular shaft using positioning pins to prevent movement during processing, the step of processing the irregular shaft simulation sleeve includes, with reference to the positions of the part limiting grooves 5 at both ends of the irregular shaft, machining contour limiting grooves radially on the side walls at both ends of the irregular shaft simulation sleeve blank.

[0055] The pre-processing positioning shaft assembly step further includes machining a first positioning pin hole along the radial direction of the second positioning shaft, referring to the position of the contour limiting groove at one end of the irregular shaft simulated sleeve blank.

[0056] The machining bushing step also includes machining a second positioning pin hole along the inner axis of the bushing, referring to the position of the contour limiting groove at the other end of the irregular shaft simulated sleeve blank.

[0057] Example 7 This embodiment provides a method for manufacturing an irregular shaft fixture. The main difference from Embodiment 5 or Embodiment 6 is that, in this embodiment, in order to facilitate the installation and positioning between the second positioning shaft and the bushing, the bushing processing step further includes: sequentially processing a shaft mounting hole that is clearance-fitted with one end of the second positioning shaft and a bolt hole for connecting one end of the second positioning shaft along the central axis direction of the bushing from the inner side to the outer end.

[0058] The pre-processing positioning shaft assembly step further includes: machining a threaded hole 20 along the central axis of one end of the second positioning shaft to be used in conjunction with the bolt hole.

[0059] The assembly step further includes machining a process hole along the radial direction of the second positioning axis, with reference to the position of the simulated positioning hole, and the process hole passing through the center of the simulated positioning hole.

[0060] Specifically, for ease of operation, after machining the process hole, the step of machining the machine tool ejector pin hole can be as follows: On a reference platform, use a V-block to horizontally support the outer circle of the irregular shaft simulating the sleeve of the temporary assembly fixture. Ensure the outer circle of the irregular shaft simulating the sleeve is level, determine the height from the center of the process hole to the reference platform, then rotate the temporary assembly fixture around the process hole as the rotation center, adjusting the support height of the temporary assembly fixture to ensure the height from the center of the process hole to the reference platform remains constant, and clamp and fix the temporary assembly fixture. Then, machine tool ejector pin holes are machined along the same horizontal axis at the outer end of the bushing and the other end of the round bar, ensuring that this horizontal axis intersects the central axis of the second positioning axis at the center of the process hole. The rotation angle value of the temporary assembly fixture is twice the bending angle value at both ends of the irregular shaft.

[0061] That is, when installing and machining the irregular shaft in the later stage, the center of the shaft hole of the irregular shaft coincides with the center of the process hole.

[0062] Example 8 This embodiment provides a method for machining irregularly shaped shafts using the irregularly shaped shaft fixture provided in any of embodiments 1 to 4, such as... Figure 4 , Figure 5 and Figure 6 As shown, it includes the following steps: In one assembly process, one end of the second positioning shaft is passed through the shaft hole of the irregular shaft blank and detachably connected to the bushing, so that the irregular shaft blank is clamped between the inner side of the first positioning shaft and the inner side of the bushing. Then, the machine tool ejector pin is used to lift the machine tool ejector pin holes located on the outer end face of the first positioning shaft and the outer end face of the bushing respectively, and the outer circle of one end of the irregular shaft blank is machined. The bushing and the second positioning shaft are disassembled for secondary assembly processing to remove the irregular shaft blank from the second positioning shaft. Then, the left and right ends of the irregular shaft blank are interchanged, and the assembly processing steps are repeated once. The outer circle of the other end of the irregular shaft blank is machined.

[0063] Example 9 This embodiment provides a method for machining irregular shafts using the above-mentioned irregular shaft fixture tooling. The main difference from Embodiment 8 is that, in order to prevent the irregular shaft blank from moving during the machining process, the first assembly machining step further includes, before turning the outer circle of one end of the irregular shaft blank, aligning the part limiting groove at one end of the irregular shaft with the first positioning pin hole on the second positioning shaft, and aligning the part limiting groove at the other end of the irregular shaft with the second positioning pin hole inside the bushing, and then installing positioning pins in the first positioning pin hole and the second positioning pin hole respectively.

[0064] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them; although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications can still be made to the specific implementation of the present invention or equivalent substitutions can be made to some technical features without departing from the spirit of the technical solutions of the present invention, and all such modifications and substitutions should be covered within the scope of the technical solutions claimed in the present invention.

Claims

1. A method for manufacturing an irregularly shaped shaft fixture, characterized in that: The irregular shaft fixture includes a positioning shaft assembly and a bushing. The positioning shaft assembly includes a first positioning shaft and a second positioning shaft connected together. One end of the second positioning shaft passes through the irregular shaft hole and is detachably connected to the bushing. A clamping space for clamping the irregular shaft is formed between the inner side of the first positioning shaft and the inner side of the bushing. Machine tool ejector holes are respectively provided on the outer end face of the first positioning shaft and the outer end face of the bushing. The central axes of the two machine tool ejector holes located on the outer end face of the first positioning shaft and the outer end face of the bushing coincide. The central axis of the machine tool ejector hole intersects the central axis of the second positioning shaft at the center of the irregular shaft hole, and the included angle formed is an acute angle. Twice the included angle value is complementary to the bending angle value of the irregular shaft. A shaft mounting hole is provided at the inner end of the bushing. One end of the second positioning shaft is clearance-fitted with the shaft mounting hole and connected to the bushing by a fastening screw. A process hole is provided along the radial direction of the second positioning shaft, and the process hole passes through the center of the irregular shaft hole. Includes the following steps: Machining the irregular shaft simulation sleeve: Referring to the diameter of the irregular shaft hole and the horizontal projection length of the hole, a blank for the irregular shaft simulation sleeve is machined. The inner diameter of the hollow straight cylinder and the length of the blank are the same as the diameter of the irregular shaft hole and the horizontal projection length of the hole, respectively. A simulated positioning hole is machined along the radial direction of the irregular shaft simulation sleeve blank, and the simulated positioning hole passes through the center of the hollow straight cylinder of the irregular shaft simulation sleeve blank. Pre-machined positioning shaft assembly: Machining a stepped shaft with a second positioning shaft at the inner end; Machining bushing: Machining a bushing that can be detachably connected to one end of the second positioning shaft; Assembly: Pass one end of the second positioning shaft through the irregular shaft simulation sleeve and detachably connect it to the bushing to form a temporary assembly fixture; Machining machine tool ejector pin holes: The temporary assembly fixture is placed horizontally, and rotated around the central axis of the simulated positioning hole as the horizontal rotation axis. After rotation into place, it is fixed. Machine tool ejector pin holes are machined along the same horizontal axis on the outer end face of the bushing and the outer end face of the stepped shaft, respectively. The horizontal axis of the machine tool ejector pin hole intersects the central axis of the second positioning axis at the center of the hollow straight cylinder of the irregular shaft simulated sleeve blank. The rotation angle value of the temporary assembly fixture is twice that of the bending angle value of the irregular shaft. Machining the positioning shaft assembly: respectively pressing the machine tool ejector pin holes located on the outer end face of the bushing and the outer end face of the stepped shaft, machining the outer end of the stepped shaft into a first positioning shaft, the central axis of the first positioning shaft coincides with the central axis of the two machine tool ejector pin holes.

2. The method for manufacturing the irregular shaft fixture according to claim 1, characterized in that: A first positioning pin hole is provided along the radial direction of the second positioning axis for cooperating with the part limiting groove at one end of the irregular shaft, and a second positioning pin hole is provided along the inner axial direction of the bushing for cooperating with the part limiting groove at the other end of the irregular shaft. The step of processing the irregular shaft simulation sleeve further includes: referring to the position of the part limiting groove at both ends of the irregular shaft, machining the contour limiting grooves radially on the side walls at both ends of the irregular shaft simulation sleeve blank; The pre-processing positioning shaft assembly step further includes: referring to the position of the contour limiting groove at one end of the irregular shaft simulated sleeve blank, machining a first positioning pin hole along the radial direction of the second positioning shaft; The machining bushing step further includes: referring to the position of the contour limiting groove at the other end of the irregular shaft simulated sleeve blank, machining a second positioning pin hole along the inner axis of the bushing.

3. The method for manufacturing the irregular shaft fixture according to claim 2, characterized in that: The machining bushing step further includes: machining a shaft mounting hole that is clearance-fitted with one end of the second positioning shaft and a bolt hole for fixing and connecting one end of the second positioning shaft along the central axis direction of the bushing from the inner side to the outer end of the bushing. The pre-processing of the positioning shaft assembly further includes: machining a threaded hole along the central axis of one end of the second positioning shaft to match the bolt hole.

4. The method for manufacturing the irregular shaft fixture according to claim 3, characterized in that: The assembly step further includes: referring to the position of the simulated positioning hole, machining a process hole in the radial direction of the second positioning axis, the process hole passing through the center of the hollow straight cylinder of the irregular shaft simulated sleeve blank.

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