A fixture and method for machining the outer profile of a non-rotating conical thin-walled part

Abstract

The present invention discloses a fixture and method for processing the outer profile of a non-rotating conical thin-walled part. The fixture includes an external support unit, an internal support unit, and a tailstock unit. The external support unit is used to contact and position the outer profile of the workpiece, the internal support unit is used to contact and position the inner profile of the workpiece, and the tailstock unit is used to contact and position the spherical end face of the left end of the outer profile of the workpiece. Since the present invention adopts a central push rod, a first support member and a flexible support, a second support member and a flexible support, an external bracket and a flexible support, a tail top cone and its accessory parts to support and clamp the non-rotating conical thin-walled part from multiple locations on both the inside and outside sides, the non-rotating conical thin-walled part can be firmly and reliably clamped. The present invention adopts a flexible support that can be precisely formed according to the shape of the workpiece to position the workpiece over a large area, achieving a high efficiency in the positioning and adjustment process and high positioning accuracy.

Description

Technical Field

[0001] The invention belongs to the field of mechanical processing fixtures, and relates to a fixture and a method for machining the outer profile of a non-rotating conical thin-walled part. Background Art

[0002] The radome is a large conical thin-walled part used in aircraft. It is made of fused quartz with a Mohs hardness of 7, a Vickers hardness of HV260, and an elastic modulus of approximately 72.4×10 3 MPa, and a tensile strength of 34.4 MPa. It has the characteristics of high hardness, low elastic modulus, high compressive strength and low tensile strength, as well as poor plastic toughness and good heat resistance. The shape characteristics of the conical thin-walled parts make the parts have strong axial compressive resistance and are easy to deform when clamped in the radial direction. The traditional positioning method for such parts uses scattered cover plates for combination. After the workpiece (3) is restricted in freedom, the relative positions of each cover plate need to be adjusted continuously. This clamping method makes the positioning accuracy of the clamped parts low. In addition, during the measurement or processing process, the position of the antenna cover needs to be frequently changed to meet the test posture at different positions. The fixture needs to be manually disassembled, the antenna cover needs to be re-positioned, and then the corresponding fixture is installed and re-marked. This operation process makes the processing efficiency extremely low. The traditional processing method uses manual fixed-point measurement, and then uses a grinding wheel to process until the local area close to the interference, and then replaces the tool in sequence and re-changes the position of the part relative to the fixture. This processing method makes the processing accuracy low and the consistency poor. With the development of radar technology, the corresponding radome needs to be mass-produced. At this time, it is also necessary to invent new fixtures to meet the demand for radar system radome parts. 。

[0003] Chinese patent CN112207465B discloses a “fixture and clamping method for laser processing the inner and outer wall surfaces of a tapered thin-walled rotating part”, which uses a clamping component to clamp and position the large end of the tapered thin-walled part, and uses the rotation of the workbench to drive the fixture to achieve processing of the outer surface of the workpiece (3). However, this clamping method only clamps and positions the large end of the workpiece (3), which easily causes the workpiece (3) to be greatly deformed during the processing process.

[0004] Chinese patent CN112338831B discloses a "clamp suitable for tapered thin-walled parts." This clamp utilizes a clamping rod and a stopper rod to clamp and support the part from both the inside and outside of the tapered thin-walled part. The clamping rod and stopper rod swing with the tapered thin-walled part's taper angle, making them suitable for machining tapered thin-walled parts with a variety of taper angles. However, this clamping method cannot fully machine the entire outer surface of a tapered thin-walled part due to interference between the grinding wheel and the clamp. Therefore, it does not effectively address the machining issues associated with tapered thin-walled parts. Summary of the Invention

[0005] In order to solve the above problems existing in the prior art, the present invention designs a fixture and method for machining the outer profile of non-rotating conical thin-walled parts, which has firm and reliable clamping, high positioning accuracy and high machining efficiency.

[0006] In order to achieve the above object, the technical solution of the present invention is as follows:

[0007] A fixture for machining the outer profile of a non-rotating tapered thin-walled part, comprising an external support unit, an internal support unit, and a tailstock unit. The external support unit is used to contact and position the outer profile of the workpiece, the internal support unit is used to contact and position the inner profile of the workpiece, and the tailstock unit is used to contact and position the spherical end surface at the left end of the outer profile of the workpiece. The tailstock unit, the external support unit, and the internal support unit are all fixed to a bed base.

[0008] The tailstock unit includes a tailstock, a tail cone, a guide rail clamp B and a slider B;

[0009] The tailstock is fixedly connected to the left end of the tail cone by threaded engagement; the bottom of the tailstock is fixedly connected to the guide rail clamp B and the slider B by bolts respectively; the slider B is slidably connected to the guide rail and moves back and forth along the guide rail, and the guide rail is fixed to the bed base by bolts; when the tailstock is limited, the guide rail clamp B locks the tailstock to the guide rail;

[0010] The tail cone is a tubular structure with a tapered hole at the right end for contact and positioning with the workpiece;

[0011] The external support unit includes an upper flexible support connecting plate, an upper flexible support, an external bracket, a guide rail clamp A, a slider A, a lower flexible support, a lower flexible support connecting plate, a left flexible support, a left flexible support connecting plate, a right flexible support and a right flexible support connecting plate;

[0012] The external bracket is an L-shaped structure, including a trapezoidal plate and a fixed plate;

[0013] A through hole is provided on the upper portion of the trapezoidal plate, and the diameter of the through hole is the same as the maximum dimension of the workpiece at a length of / - / from the left end;

[0014] An upper flexible support connecting plate, a left flexible support connecting plate, a lower flexible support connecting plate, and a right flexible support connecting plate are fixedly connected in sequence along the circumference of the through hole on the trapezoidal plate outside the through hole; an upper flexible support, a lower flexible support, a left flexible support, and a right flexible support are fixed on the inner sides of the upper flexible support connecting plate, the lower flexible support connecting plate, the left flexible support, and the right flexible support, respectively, and the inner ends of the upper flexible support, the lower flexible support, the left flexible support, and the right flexible support are all in contact with the outer contour surface of the workpiece;

[0015] The lower portion of the fixing plate is fixedly connected to the guide rail clamp A and the slider A by bolts; the slider A is slidably connected to the guide rail and moves back and forth along the guide rail; when the external bracket is limited, the guide rail clamp A locks the external bracket on the guide rail;

[0016] The internal support unit includes a mandrel rotation spindle, a central mandrel, a second support member, a second flexible support A, a second flexible support connecting plate A, a first support member, a first flexible support A, a first flexible support connecting plate A, a limiting ring fastening bolt, a first support member fastening bolt A, a key, a CNC turntable, a mandrel fixing bolt, an internal support tube, a limiting ring, a mandrel connecting nut, a ball bearing A, a ball bearing B, an outer spacer, an inner spacer, a ball bearing C, a rear spacer, a mandrel locking nut, a second flexible support connecting plate B, a second flexible support B, a second flexible support connecting plate C, a second flexible support C, a second flexible support D, a second flexible support connecting plate D, a first support member fastening bolt B, a first flexible support connecting plate B, a first flexible support B, a first flexible support connecting plate C, a first flexible support C, a first flexible support connecting plate D and a first flexible support D;

[0017] The internal support tube is a circular tube structure, with the left end fixedly connected to the second support member, the middle part connected to the first support member, and a boss provided at the right end, which is fixedly connected to the CNC turntable by bolts and nuts;

[0018] The first support member is connected to the inner support tube via a key, so as to limit the circumferential rotation of the first support member;

[0019] The limiting ring is located on the right side of the first support member, and the limiting ring is connected to the internal support tube through a key to limit the circumferential rotation of the limiting ring;

[0020] The left section of the first support member is a circular tube, the inner diameter of the circular tube is equal to the outer diameter of the internal support tube, and the inner circular surface of the circular tube is connected to the outer circular surface of the internal support tube; the right section of the first support member is a plate-like structure, the shape and taper of its outer contour surface match the inner contour surface at the corresponding position of the workpiece, and is in contact and positioned with the inner contour surface of the workpiece; the right end surface of the plate-like structure is fixedly connected to the first flexible support connecting plate A, the first flexible support connecting plate B, the first flexible support connecting plate C and the first flexible support connecting plate D respectively; the outer sides of the first flexible support connecting plate A, the first flexible support connecting plate B, the first flexible support connecting plate C and the first flexible support connecting plate D are fixedly connected to the first flexible support A, the first flexible support B, the first flexible support C and the first flexible support D respectively, and the outer ends of the first flexible support A, the first flexible support B, the first flexible support C and the first flexible support D are all in contact with the inner contour surface of the workpiece;

[0021] The second support member is a plate-like structure, the shape and taper of its outer profile match the inner profile of the corresponding position of the workpiece, and is in contact with and positioned on the inner profile of the workpiece; the left end surface of the second support member is fixedly connected to the second flexible support connecting plate A, the second flexible support connecting plate B, the second flexible support connecting plate C, and the second flexible support connecting plate D respectively; the outer sides of the second flexible support connecting plate A, the second flexible support connecting plate B, the second flexible support connecting plate C, and the second flexible support connecting plate D are fixedly connected to the second flexible support A, the second flexible support B, the second flexible support C, and the second flexible support D respectively, and the outer ends of the second flexible support A, the second flexible support B, the second flexible support C, and the second flexible support D are all in contact with the inner profile of the workpiece;

[0022] The central push rod is nested in the internal support tube, with both ends extending out of the internal support tube; the central push rod is fixedly connected to the internal support tube by a push rod fixing bolt;

[0023] The center of the left end of the central mandrel is provided with three stepped holes. The left section is a threaded hole, which is connected to the mandrel connecting nut by a thread; the middle section is a smooth hole, which is connected to the outer circumference of ball bearing A, ball bearing B, outer spacer and ball bearing C in sequence; the right section is a smooth hole, the diameter of which is larger than the maximum circumscribed circle diameter of the mandrel locking nut; the annular end face of the left end of the central mandrel is in contact with the outer annular end face of the right end of ball bearing C for positioning;

[0024] The left end of the push rod rotating spindle is a spherical surface, which contacts and positions with the spherical end surface of the left end of the inner contour of the workpiece; the right end of the push rod rotating spindle is fixedly connected to the push rod locking nut; the left section of the push rod rotating spindle is a cylinder; the middle section of the push rod rotating spindle is a cylinder, and is connected to the inner side of the push rod connecting nut; the right section of the push rod rotating spindle is a cylinder, which is nested in ball bearing A, ball bearing B, outer spacer, inner spacer, ball bearing C and rear spacer from left to right; the diameter of the left section of the push rod rotating spindle is greater than the diameter of the middle section of the cylinder, and the diameter of the middle section of the cylinder is greater than the diameter of the right section of the cylinder; the right side annular end surface of the left end of the push rod rotating spindle and the left end surface of the push rod connecting nut are contacted and positioned.

[0025] Furthermore, the first flexible support connecting plate A, the first flexible support connecting plate B, the first flexible support connecting plate C, the first flexible support connecting plate D, the second flexible support connecting plate A, the second flexible support connecting plate B, the second flexible support connecting plate C and the second flexible support connecting plate D have the same structure, and are all square blocks with holes;

[0026] The upper flexible support, lower flexible support, left flexible support, right flexible support, first flexible support A, first flexible support B, first flexible support C, first flexible support D, second flexible support A, second flexible support B, second flexible support C and second flexible support D have the same structure, including a support block and a pin. The pin is a pin with an independent rebound function, and the pin is installed on the outside of the support block for contacting the surface of the workpiece.

[0027] Furthermore, flexible gaskets are respectively provided between the first support member and the workpiece, between the second support member and the workpiece, and between the tail cone and the workpiece to prevent damage to the workpiece during the positioning process.

[0028] Furthermore, a countersunk through hole is provided on the top of the limiting ring, a through hole is provided at a position corresponding to the key and the countersunk through hole of the limiting ring, a threaded hole is provided at a position corresponding to the through hole of the key on the internal support tube, and the limiting ring fastening bolts pass through the countersunk through hole of the limiting ring and the through hole of the key and are fixedly connected to the threaded hole of the internal support tube to perform axial and radial positioning of the limiting ring.

[0029] Furthermore, threaded holes are symmetrically provided on both sides of the limiting ring key groove, and the first support member fastening bolt A and the first support member fastening bolt B are fixedly connected to the threaded holes of the limiting ring and press against the first support member to axially position the first support member.

[0030] Furthermore, the mandrel rotation spindle rotates around the axis, preventing the workpiece from being damaged by friction between the mandrel spindle and the workpiece when the workpiece rotates around the axis.

[0031] A method for machining the outer profile of a non-rotating tapered thin-walled part, using a fixture for machining the outer profile of a non-rotating tapered thin-walled part for positioning, specifically comprising the following steps:

[0032] A. Install the workpiece

[0033] Move the tailstock and the external support to the far left end of the guide rail to leave space for lifting the workpiece. Lift the workpiece so that the inner cavity of the large end of the workpiece passes through the second support and the first support in sequence until the workpiece contacts the outer contour of the second support and the pin on the top of the second flexible support on the second support. At this time, hold the workpiece by hand and push the first support until the workpiece cannot rotate in a circumferential direction. Tighten the first support fastening bolt A and the first support fastening bolt B, lock the first support, push the center push rod until the spherical surface of the push rod rotating spindle contacts the spherical end surface of the inner contour of the workpiece, tighten the push rod fixing bolt, lock the center push rod, move the tailstock to the right, so that the tail top cone contacts the spherical end surface of the outer contour of the workpiece, lock the tailstock to the guide rail through the guide rail clamp B, and now process the outer contour of the workpiece except the spherical end surface.

[0034] B. Move the tailstock and external bracket to process the spherical end surface of the workpiece

[0035] Move the external bracket to the right until the inner ends of the upper flexible support, lower flexible support, left flexible support and right flexible support contact the outer contour surface of the workpiece, lock the external bracket on the guide rail through the guide rail clamp A, release the lock of the guide rail clamp B on the tailstock, move the tailstock to the far left end, and then process the spherical end face of the workpiece.

[0036] Compared with the prior art, the present invention has the following beneficial effects:

[0037] 1. The present invention uses a central push rod, a first support member and a flexible support, a second support member and a flexible support, an external bracket and a flexible support, a tail cone and its accessories to support and clamp the non-rotating conical thin-walled parts from multiple locations on both the inside and outside sides, thereby firmly and reliably clamping the non-rotating conical thin-walled parts.

[0038] 2. Because the present invention utilizes a flexible support that can be precisely formed to the workpiece's shape to position a large workpiece area, the axially adjustable first support, external bracket, and tail cone each contact and position the workpiece's inner and outer contours, as well as its spherical end face, enabling precise positioning of non-rotating conical, thin-walled parts. This results in a highly efficient positioning and adjustment process with high positioning accuracy.

[0039] 3. Since the present invention adopts a tail top cone and an external bracket that can alternately perform contact positioning on the non-rotating outer contour surface, as well as a first support member and its flexible support and a second support member and its flexible support that can rotate with the CNC turntable, it can meet the different posture requirements during measurement and processing, and achieve improved processing efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 This is a full cross-sectional view of a non-rotating conical thin-walled part being clamped by a fixture.

[0041] Figure 2 This is a partial enlarged view of the first support part.

[0042] Figure 3 This is a partial enlarged view of the left end of the center push rod.

[0043] Figure 4 It is a transverse cross-sectional view along the large end of a non-rotating conical thin-walled part.

[0044] Figure 5 This is the second support tooling view.

[0045] Figure 6 This is the tooling view of the external support unit.

[0046] Figure 7 yes Figure 1 Axonometric drawing of .

[0047] In the figure: 1. Tailstock, 2. Tail cone, 3. Workpiece, 4. Mandrel rotating spindle, 5. Upper flexible support connecting plate A, 6. Upper flexible support, 7. External bracket, 8. Center mandrel, 9. Second support, 10. Second flexible support connecting plate A, 11. Second flexible support A, 12. First support, 13. First flexible support A, 14. First flexible support connecting plate A, 15. Limiting ring fastening bolt, 16. First support fastening bolt A, 17, key, 18, CNC turntable, 19, push rod fixing bolt, 20, internal support tube, 21, limit ring, 22, guide rail clamp A, 23, slider A, 24, lower flexible support, 25, lower flexible support connecting plate, 26, guide rail, 27, guide rail clamp B, 28, slider B, 29, bed base, 30, left flexible support, 31, left flexible support connecting plate, 32, right flexible support, 33, right flexible support connecting plate, 34. Push rod connecting nut, 35. Ball bearing A, 37. Ball bearing B, 37. Outer spacer, 38. Inner spacer, 39. Ball bearing C, 40. Rear spacer, 41. Push rod locking nut, 42. Second flexible support connecting plate B, 43. Second flexible support B, 44. Second flexible support connecting plate C, 45. Second flexible support C, 46. Second flexible support D, 47. Second flexible support connecting plate D, 48. First support member fastening bolt B, 49. First flexible support connecting plate B, 50. First flexible support B, 51. First flexible support connecting plate C, 52. First flexible support C, 53. First flexible support connecting plate D, 54. First flexible support D. DETAILED DESCRIPTION

[0048] The present invention will be further described below in conjunction with the accompanying drawings. Figure 1-7 As shown, a fixture for machining the outer profile of a non-rotating tapered thin-walled part comprises an external support unit, an internal support unit, and a tailstock unit. The external support unit is used to contact and position the outer profile of a workpiece 3, the internal support unit is used to contact and position the inner profile of the workpiece 3, and the tailstock unit is used to contact and position the spherical end surface at the left end of the outer profile of the workpiece 3. The tailstock unit, the external support unit, and the internal support unit are all fixed to a bed base 29.

[0049] The tailstock unit includes a tailstock 1, a tail cone 2, a guide rail clamp B27 and a slider B28;

[0050] The tailstock 1 is fixedly connected to the left end of the tail cone 2 by threaded engagement; the bottom of the tailstock 1 is fixedly connected to the guide rail clamp B27 and the slider B28 by bolts respectively; the slider B28 is slidably connected to the guide rail 26 and moves back and forth along the guide rail 26, and the guide rail 26 is fixed to the bed base 29 by bolts; when the tailstock 1 is limited, the guide rail clamp B27 locks the tailstock 1 to the guide rail 26;

[0051] The tail cone 2 is a tubular structure with a tapered hole at the right end for contacting and positioning with the workpiece 3;

[0052] The external support unit includes an upper flexible support connecting plate 5, an upper flexible support 6, an external bracket 7, a guide rail clamp A22, a slider A23, a lower flexible support 24, a lower flexible support connecting plate 25, a left flexible support 30, a left flexible support connecting plate 31, a right flexible support 32 and a right flexible support connecting plate 33;

[0053] The external bracket 7 is an L-shaped structure, including a trapezoidal plate and a fixed plate;

[0054] A through hole is provided on the upper portion of the trapezoidal plate, and the diameter of the through hole is the same as the maximum dimension of the workpiece 3 at a distance of 1 / 4-1 / 3 from the left end;

[0055] On the trapezoidal plate outside the through hole, an upper flexible support connecting plate 5, a left flexible support connecting plate 31, a lower flexible support connecting plate 25 and a right flexible support connecting plate 33 are fixedly connected in sequence along the circumference of the through hole; an upper flexible support 6, a lower flexible support 24, a left flexible support 30 and a right flexible support 32 are fixed to the inner sides of the upper flexible support connecting plate 5, the lower flexible support connecting plate 25, the left flexible support connecting plate 31 and the right flexible support connecting plate 33 respectively, and the inner ends of the upper flexible support 6, the lower flexible support 24, the left flexible support 30 and the right flexible support 32 are all in contact with the outer contour surface of the workpiece 3;

[0056] The lower portion of the fixing plate is fixedly connected to the guide rail clamp A22 and the slider A23 by bolts; the slider A23 is slidably connected to the guide rail 26 and moves back and forth along the guide rail 26; when the external bracket is limited, the guide rail clamp A22 locks the external bracket on the guide rail 26;

[0057] The internal support unit includes a mandrel rotating spindle 4, a central mandrel 8, a second support member 9, a second flexible support A10, a second flexible support connecting plate A11, a first support member 12, a first flexible support A13, a first flexible support connecting plate A14, a limiting ring fastening bolt 15, a first support fastening bolt A16, a key 17, a CNC turntable 18, a mandrel fixing bolt 19, an internal support tube 20, a limiting ring 21, a mandrel connecting nut 34, a ball bearing A35, a ball bearing B36, an outer spacer 37, and an inner spacer 38. 8. Ball bearing C39, rear spacer 40, push rod locking nut 41, second flexible support connecting plate B42, second flexible support B43, second flexible support connecting plate C44, second flexible support C45, second flexible support D46, second flexible support connecting plate D47, first support member fastening bolt B48, first flexible support connecting plate B49, first flexible support B50, first flexible support connecting plate C51, first flexible support C52, first flexible support connecting plate D53, and first flexible support D54;

[0058] The internal support tube 20 is a circular tube structure, with the left end fixedly connected to the second support member 9, the middle part connected to the first support member 12, and a boss provided on the right end, which is fixedly connected to the CNC turntable 18 by bolts and nuts;

[0059] The first support member 12 is connected to the inner support tube 20 via a key 17 to limit the circumferential rotation of the first support member 12;

[0060] The limiting ring 21 is located to the right of the first support member 12 and is connected to the internal support tube 20 via a key 17 to limit the circumferential rotation of the limiting ring 21;

[0061] The left section of the first support member 12 is a circular tube, the inner diameter of the circular tube is equal to the outer diameter of the internal support tube 20, and the inner circular surface of the circular tube is connected to the outer circular surface of the internal support tube 20; the right section of the first support member 12 is a plate-like structure, the shape and taper of its outer contour surface match the inner contour surface of the corresponding position of the workpiece 3, and is in contact and positioned with the inner contour surface of the workpiece 3; the right end surface of the plate-like structure is fixedly connected to the first flexible support connecting plate A14, the first flexible support connecting plate B49, the first flexible support connecting plate C51 and the first flexible support connecting plate D53 respectively; the outer sides of the first flexible support connecting plate A14, the first flexible support connecting plate B49, the first flexible support connecting plate C51 and the first flexible support connecting plate D53 are fixedly connected to the first flexible support A13, the first flexible support B50, the first flexible support C52 and the first flexible support D54 respectively, and the outer ends of the first flexible support A13, the first flexible support B50, the first flexible support C52 and the first flexible support D54 are all in contact with the inner contour surface of the workpiece 3;

[0062] The second support member 9 is a plate-like structure, the shape and taper of its outer profile match the inner profile of the corresponding position of the workpiece 3, and is in contact with and positioned on the inner profile of the workpiece 3; the left end face of the second support member 9 is fixedly connected to the second flexible support connecting plate A11, the second flexible support connecting plate B42, the second flexible support connecting plate C44, and the second flexible support connecting plate D47 respectively; the outer sides of the second flexible support connecting plate A11, the second flexible support connecting plate B42, the second flexible support connecting plate C44, and the second flexible support connecting plate D47 are fixedly connected to the second flexible support A10, the second flexible support B43, the second flexible support C45, and the second flexible support D46, and the outer ends of the second flexible support A10, the second flexible support B43, the second flexible support C45, and the second flexible support D46 are all in contact with the inner profile of the workpiece 3;

[0063] The central push rod 8 is nested in the internal support tube 20, with both ends extending out of the internal support tube 20; the central push rod 8 is fixedly connected to the internal support tube 20 by a push rod fixing bolt 19;

[0064] The center of the left end of the central push rod 8 is provided with three stepped holes. The left section is a threaded hole, which is connected to the push rod connecting nut 34 by a threaded hole; the middle section is a smooth hole, which is connected to the outer circumference of the ball bearing A35, the ball bearing B36, the outer spacer 37 and the ball bearing C39 in sequence; the right section is a smooth hole, the diameter of which is larger than the maximum circumscribed circle diameter of the push rod locking nut 41; the annular end surface of the left end of the central push rod 8 is in contact with the outer annular end surface of the right end of the ball bearing C39 for positioning;

[0065] The left end of the push rod rotating spindle 4 is a spherical surface, which contacts and positions with the spherical end surface of the left end of the inner contour of the workpiece 3; the right end of the push rod rotating spindle 4 is fixedly connected to the push rod locking nut 41; the left section of the push rod rotating spindle 4 is a cylinder; the middle section of the push rod rotating spindle 4 is a cylinder, and is connected to the inner side of the push rod connecting nut 34; the right section of the push rod rotating spindle 4 is a cylinder, which is nested in the ball bearing A35, ball bearing B36, outer spacer 37, inner spacer 38, ball bearing C39 and rear spacer 40 from left to right; the diameter of the left section of the push rod rotating spindle 4 is greater than the diameter of the middle section of the cylinder, and the diameter of the middle section of the cylinder is greater than the diameter of the right section of the cylinder; the right side annular end surface of the left end of the push rod rotating spindle 4 is in contact and positioned with the left end surface of the push rod connecting nut 34.

[0066] Furthermore, the first flexible support connecting plate A14, the first flexible support connecting plate B49, the first flexible support connecting plate C51, the first flexible support connecting plate D53, the second flexible support connecting plate A11, the second flexible support connecting plate B42, the second flexible support connecting plate C44 and the second flexible support connecting plate D47 have the same structure, and are all square blocks with holes;

[0067] The upper flexible support 6, the lower flexible support 24, the left flexible support 30, the right flexible support 32, the first flexible support A13, the first flexible support B50, the first flexible support C52, the first flexible support D54, the second flexible support A10, the second flexible support B43, the second flexible support C45 and the second flexible support D46 have the same structure, including a support block and a pin, and the pin is a pin with an independent rebound function, which is installed on the outside of the support block and is used to contact the surface of the workpiece 3.

[0068] Furthermore, flexible gaskets are respectively provided between the first support member 12 and the workpiece 3 , between the second support member 9 and the workpiece 3 , and between the tail cone 2 and the workpiece 3 to prevent damage to the workpiece 3 during the positioning process.

[0069] Furthermore, a countersunk through hole is provided on the top of the limiting ring 21, a through hole is provided at a position corresponding to the key 17 and the countersunk through hole of the limiting ring 21, a threaded hole is provided at a position corresponding to the through hole of the key 17 on the internal support tube 20, and the limiting ring fastening bolt 15 passes through the countersunk through hole of the limiting ring 21 and the through hole of the key 17 and is fixedly connected to the threaded hole of the internal support tube 20, thereby performing axial and radial positioning of the limiting ring 21.

[0070] Furthermore, threaded holes are symmetrically provided on both sides of the keyway of the limiting ring 21, and the first support member fastening bolt A16 and the first support member fastening bolt B48 are fixedly connected to the threaded holes of the limiting ring 21 and press against the first support member 12 to axially position the first support member.

[0071] Furthermore, the mandrel rotating spindle 4 rotates around the axis, thereby preventing the workpiece 3 from being damaged by friction between the mandrel spindle and the workpiece 3 when the workpiece 3 rotates around the axis.

[0072] A method for machining the outer profile of a non-rotating tapered thin-walled part, using a fixture for machining the outer profile of a non-rotating tapered thin-walled part for positioning, specifically comprising the following steps:

[0073] A. Install workpiece 3

[0074] Move the tailstock 1 and the external support 7 to the far left of the guide rail 26 to leave space for lifting the workpiece 3. Lift the workpiece 3 so that the inner cavity of the large end of the workpiece 3 passes through the second support 9 and the first support 12 in sequence until the workpiece 3 contacts the outer contour of the second support 9 and the pin on the top of the second flexible support on the second support 9. At this time, hold the workpiece 3 by hand and push the first support 12 until the workpiece 3 cannot rotate in the circumferential direction. Tighten the first support fastening bolt A16 and the first support fastening bolt B48, lock the first support 12, push the center push rod 8 until the spherical surface of the push rod rotating spindle 4 contacts the spherical end surface of the inner contour of the workpiece 3, tighten the push rod fixing bolt 19, lock the center push rod 8, move the tailstock 1 to the right, so that the tail top cone 2 contacts the spherical end surface of the outer contour of the workpiece 3, and lock the tailstock 1 on the guide rail 26 through the guide rail clamp 27. At this time, the outer contour of the workpiece 3 except the spherical end surface is processed.

[0075] B. Move the tailstock 1 and the external support to process the spherical end surface of the workpiece 3

[0076] Move the external support 7 to the right until the inner ends of the upper flexible support 6, the lower flexible support 24, the left flexible support 30, and the right flexible support 32 contact the outer contour surface of the workpiece 3, lock the external support 7 on the guide rail 26 through the guide rail clamp 22, release the lock of the guide rail clamp 27 on the tailstock 1, move the tailstock 1 to the far left end, and then process the spherical end surface of the workpiece 3.

[0077] The present invention is not limited to this embodiment, and any equivalent concepts or modifications within the technical scope disclosed by the present invention are included in the protection scope of the present invention.

Claims

1. A fixture for machining the outer profile of a non-rotating tapered thin-walled part, characterized by: The machine comprises an external support unit, an internal support unit and a tailstock unit, wherein the external support unit is used to contact and position the outer profile of the workpiece (3), the internal support unit is used to contact and position the inner profile of the workpiece (3), and the tailstock unit is used to contact and position the spherical end surface at the left end of the outer profile of the workpiece (3), and the tailstock unit, the external support unit and the internal support unit are all fixed on the bed base (29); The tailstock unit comprises a tailstock (1), a tail cone (2), a guide rail clamp B (27) and a slider B (28); The tailstock (1) is fixedly connected to the left end of the tail cone (2) by threaded engagement; the bottom of the tailstock (1) is fixedly connected to the guide rail clamp B (27) and the slider B (28) by bolts; the slider B (28) is slidably connected to the guide rail (26) and moves back and forth along the guide rail (26), and the guide rail (26) is fixed to the bed base (29) by bolts; when the tailstock (1) is limited, the guide rail clamp B (27) locks the tailstock (1) on the guide rail (26); The tail cone (2) is a tubular structure, with a conical hole provided at the right end for contact and positioning with the workpiece (3); The external support unit comprises an upper flexible support connecting plate (5), an upper flexible support (6), an external bracket (7), a guide rail clamp A (22), a slider A (23), a lower flexible support (24), a lower flexible support connecting plate (25), a left flexible support (30), a left flexible support connecting plate (31), a right flexible support (32) and a right flexible support connecting plate (33); The external bracket (7) is an L-shaped structure, comprising a trapezoidal plate and a fixed plate; A through hole is provided on the upper portion of the trapezoidal plate, the diameter of the through hole being the same as the maximum dimension of the workpiece (3) at a distance of 1 / 4 to 1 / 3 of the length from the left end; An upper flexible support connecting plate (5), a left flexible support connecting plate (31), a lower flexible support connecting plate (25) and a right flexible support connecting plate (33) are fixedly connected in sequence along the circumference of the through hole on the trapezoidal plate outside the through hole; an upper flexible support (6), a lower flexible support (24), a left flexible support (30) and a right flexible support (32) are fixed on the inner sides of the upper flexible support connecting plate (5), the lower flexible support connecting plate (25), the left flexible support connecting plate (31) and the right flexible support connecting plate (33), respectively, and the inner ends of the upper flexible support (6), the lower flexible support (24), the left flexible support (30) and the right flexible support (32) are in contact with the outer profile surface of the workpiece (3); The lower portion of the fixing plate is fixedly connected to the guide rail clamp A (22) and the slider A (23) by bolts; the slider A (23) is slidably connected to the guide rail (26) and moves back and forth along the guide rail (26); when the external bracket is limited, the guide rail clamp A (22) locks the external bracket on the guide rail (26); The internal support unit comprises a mandrel rotating spindle (4), a central mandrel (8), a second support member (9), a second flexible support A (10), a second flexible support connecting plate A (11), a first support member (12), a first flexible support A (13), a first flexible support connecting plate A (14), a limiting ring fastening bolt (15), a first support member fastening bolt A (16), a key (17), a CNC turntable (18), a mandrel fixing bolt (19), an internal support tube (20), a limiting ring (21), a mandrel connecting nut (34), a ball bearing A (35), a ball bearing B (36), an outer spacer (37), an inner spacer sleeve (38), ball bearing C (39), rear spacer (40), push rod locking nut (41), second flexible support connecting plate B (42), second flexible support B (43), second flexible support connecting plate C (44), second flexible support C (45), second flexible support D (46), second flexible support connecting plate D (47), first support member fastening bolt B (48), first flexible support connecting plate B (49), first flexible support B (50), first flexible support connecting plate C (51), first flexible support C (52), first flexible support connecting plate D (53) and first flexible support D (54); The internal support tube (20) is a circular tube structure, the left end of which is fixedly connected to the second support member (9), the middle portion of which is connected to the first support member (12), and the right end of which is provided with a boss, which is fixedly connected to the CNC turntable (18) via bolts and nuts; The first support member (12) is connected to the internal support tube (20) via a key (17), limiting the circumferential rotation of the first support member (12); The limiting ring (21) is located to the right of the first support member (12), and the limiting ring (21) is connected to the internal support tube (20) via a key (17), limiting the circumferential rotation of the limiting ring (21); The left section of the first support member (12) is a circular tube, the inner diameter of the circular tube is equal to the outer diameter of the internal support tube (20), and the inner circular surface of the circular tube is connected to the outer circular surface of the internal support tube (20); the right section of the first support member (12) is a plate-like structure, the shape and taper of its outer profile match the inner profile of the corresponding position of the workpiece (3), and is in contact with the inner profile of the workpiece (3) for positioning; the right end surface of the plate-like structure is fixed to the first flexible support connecting plate A (14), the first flexible support connecting plate B (49), the first flexible support connecting plate C (51) and the first flexible support connecting plate D (53) respectively. fixed connection; the outer sides of the first flexible support connecting plate A (14), the first flexible support connecting plate B (49), the first flexible support connecting plate C (51) and the first flexible support connecting plate D (53) are respectively fixedly connected to the first flexible support A (13), the first flexible support B (50), the first flexible support C (52) and the first flexible support D (54), and the outer ends of the first flexible support A (13), the first flexible support B (50), the first flexible support C (52) and the first flexible support D (54) are in contact with the inner profile surface of the workpiece (3); The second support member (9) is a plate-like structure, the shape and taper of its outer profile match the inner profile of the corresponding position of the workpiece (3), and is in contact with and positioned on the inner profile of the workpiece (3); the left end face of the second support member (9) is fixedly connected to the second flexible support connecting plate A (11), the second flexible support connecting plate B (42), the second flexible support connecting plate C (44) and the second flexible support connecting plate D (47) respectively; the outer sides of the second flexible support connecting plate A (11), the second flexible support connecting plate B (42), the second flexible support connecting plate C (44) and the second flexible support connecting plate D (47) are fixedly connected to the second flexible support A (10), the second flexible support B (43), the second flexible support C (45) and the second flexible support D (46) respectively, and the outer ends of the second flexible support A (10), the second flexible support B (43), the second flexible support C (45) and the second flexible support D (46) are in contact with the inner profile of the workpiece (3); The central push rod (8) is nested in the internal support tube (20), with both ends extending out of the internal support tube (20); the central push rod (8) is fixedly connected to the internal support tube (20) via a push rod fixing bolt (19); The center of the left end of the center push rod (8) is provided with three stepped holes. The left section is a threaded hole, which is connected to the push rod connecting nut (34) by a threaded hole; the middle section is a light hole, which is connected to the outer cylindrical surface of the ball bearing A (35), the ball bearing B (36), the outer spacer (37) and the ball bearing C (39) in sequence; the right section is a light hole, the diameter of which is larger than the maximum circumscribed circle diameter of the push rod locking nut (41); the left end annular end face of the center push rod (8) and the outer end annular end face of the right end of the ball bearing C (39) are in contact and positioned; The left end of the mandrel rotating spindle (4) is a spherical surface, which contacts and positions the spherical end surface of the left end of the inner contour surface of the workpiece (3); the right end of the mandrel rotating spindle (4) is fixedly connected to the mandrel locking nut (41); the left section of the mandrel rotating spindle (4) is a cylinder; the middle section of the mandrel rotating spindle (4) is a cylinder, and is connected to the inner side of the mandrel connecting nut (34); the right section of the mandrel rotating spindle (4) is a cylinder, which is nested in the ball bearing A (35), ball bearing B (36), outer spacer (37), inner spacer (38), ball bearing C (39) and rear spacer (40) from left to right; the diameter of the left section of the mandrel rotating spindle (4) is larger than the diameter of the middle section of the cylinder, and the diameter of the middle section of the cylinder is larger than the diameter of the right section of the cylinder; the right annular end surface of the left end of the mandrel rotating spindle (4) and the left end surface of the mandrel connecting nut (34) are contacted and positioned.

2. A fixture for machining the outer profile of a non-rotating tapered thin-walled part according to claim 1, characterized in that: The first flexible support connecting plate A (14), the first flexible support connecting plate B (49), the first flexible support connecting plate C (51), the first flexible support connecting plate D (53), the second flexible support connecting plate A (11), the second flexible support connecting plate B (42), the second flexible support connecting plate C (44) and the second flexible support connecting plate D (47) have the same structure and are all square blocks with holes; The upper flexible support (6), the lower flexible support (24), the left flexible support (30), the right flexible support (32), the first flexible support A (13), the first flexible support B (50), the first flexible support C (52), the first flexible support D (54), the second flexible support A (10), the second flexible support B (43), the second flexible support C (45) and the second flexible support D (46) have the same structure, including a support block and a pin, wherein the pin is a pin with an independent rebound function, and the pin is installed on the outside of the support block and is used to contact the surface of the workpiece (3).

3. The fixture for machining the outer profile of a non-rotating tapered thin-walled part according to claim 1, characterized in that: Flexible gaskets are respectively provided between the first support member (12) and the workpiece (3), between the second support member (9) and the workpiece (3), and between the tail cone (2) and the workpiece (3) to prevent damage to the workpiece (3) during the positioning process.

4. A fixture for machining the outer profile of a non-rotating tapered thin-walled part according to claim 1, characterized in that: A countersunk through hole is provided on the top of the limiting ring (21), a through hole is provided at a position corresponding to the key (17) and the countersunk through hole of the limiting ring (21), a threaded hole is provided at a position corresponding to the through hole of the key (17) in the internal support tube (20), and a limiting ring fastening bolt (15) passes through the countersunk through hole of the limiting ring (21) and the through hole of the key (17) and is fixedly connected to the threaded hole of the internal support tube (20), thereby axially and radially positioning the limiting ring (21).

5. The fixture for machining the outer profile of a non-rotating tapered thin-walled part according to claim 1, characterized in that: Threaded holes are symmetrically provided on both sides of the keyway of the limiting ring (21), and the first support member fastening bolt A (16) and the first support member fastening bolt B (48) are fixedly connected to the threaded holes of the limiting ring (21) and press against the first support member (12) to axially position the first support member.

6. The fixture for machining the outer profile of a non-rotating tapered thin-walled part according to claim 1, characterized in that: The mandrel rotating spindle (4) rotates around the axis, preventing the workpiece (3) from being damaged by friction between the mandrel spindle and the workpiece (3) when the workpiece (3) rotates around the axis.

7. A method for machining the outer profile of a non-rotating tapered thin-walled part, characterized in that: Positioning is performed using the fixture for machining the outer profile of a non-rotating tapered thin-walled part as claimed in claim 1, specifically comprising the following steps: A. Installing the workpiece (3) Move the tailstock (1) and the external support (7) to the leftmost end of the guide rail (26) to leave space for the workpiece (3) to be hoisted. Hoist the workpiece (3) so that the inner cavity of the large end of the workpiece (3) passes through the second support (9) and the first support (12) in sequence until the workpiece (3) contacts the outer profile of the second support (9) and the pin on the top of the second flexible support on the second support (9). At this time, hold the workpiece (3) by hand and push the first support (12) until the workpiece (3) cannot rotate in the circumferential direction. Tighten the first support fastening bolt A (1 6) and the first support fastening bolt B (48), lock the first support (12), push the center push rod (8) until the spherical surface of the push rod rotating spindle (4) contacts the spherical end surface of the inner profile of the workpiece (3), tighten the push rod fixing bolt (19), lock the center push rod (8), move the tailstock (1) to the right, so that the tail top cone (2) contacts the spherical end surface of the outer profile of the workpiece (3), and lock the tailstock (1) on the guide rail (26) through the guide rail clamp B (27). At this time, the outer profile of the workpiece (3) except the spherical end surface is processed; B. Move the tailstock (1) and the external support to process the spherical end surface of the workpiece (3) Move the external support (7) to the right until the inner ends of the upper flexible support (6), the lower flexible support (24), the left flexible support (30), and the right flexible support (32) contact the outer contour surface of the workpiece (3), lock the external support (7) to the guide rail (26) through the guide rail clamp A (22), release the lock of the tailstock (1) by the guide rail clamp B (27), move the tailstock (1) to the leftmost end, and then process the spherical end surface of the workpiece (3).

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