Clamp for preventing turning deformation of nylon thin-wall disc part
By improving the fixture design, the rigidity and positioning of thin-walled nylon disc parts are enhanced, the deformation problem during turning is solved, and efficient machining results are achieved, making them suitable for mass production.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- SHANXI PINGYANG IND MACHINERY
- Filing Date
- 2025-04-25
- Publication Date
- 2026-04-24
AI Technical Summary
When machining thin-walled nylon disc-shaped parts on conventional lathes or CNC lathes, there are deformation problems caused by thermal expansion and cutting forces. Existing clamping methods cannot meet the requirements of the drawings and have low machining efficiency.
A fixture for preventing deformation of thin-walled nylon disc-shaped parts during turning is adopted, comprising a fixture body, a fixture cover, and a fixture sheet-like pressure plate. By enhancing the rigidity and positioning of the workpiece and changing the clamping method, deformation caused by cutting force is avoided. The fixture body and cover provide multi-point support and positioning for the workpiece.
It effectively reduces workpiece deformation, increases processing efficiency by 5-10 times, ensures product quality, and meets the needs of mass production.
Smart Images
Figure CN224158092U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of machining fixture technology, and specifically relates to a fixture for preventing deformation of thin-walled nylon disc-shaped parts during turning. Background Technology
[0002] When machining thin-walled nylon disc-shaped parts on conventional lathes or CNC lathes, using special tooling designed with existing process schemes to clamp the workpiece results in significant workpiece deformation during machining, failing to meet drawing requirements and exhibiting low machining efficiency, making it unsuitable for mass production.
[0003] Taking a product bracket as an example, the existing technical solution is explained below: The product bracket is made of nylon rods, and its structure is as follows... Figure 1 As shown, after machining the outer diameter and inner hole, the wall thickness is 2mm, and the wall thickness at the right end is 3mm, making it a typical thin-walled disc-type structural part. Through analysis of the workpiece's structural characteristics and the selected material, the following two machining difficulties exist when machining this workpiece on a conventional lathe or CNC lathe:
[0004] 1. Although the workpiece shape is simple, the part itself has poor heat dissipation and a large coefficient of thermal expansion, so the part is greatly affected by thermal deformation during the turning process.
[0005] 2. The part is made of nylon, which has low strength and poor rigidity, and the workpiece wall is extremely thin. During the processing, the cutting force has a great influence on the deformation of the workpiece.
[0006] Significant thermal expansion and cutting forces can cause substantial deformation of parts during turning, making it difficult to guarantee dimensional accuracy. Therefore, to reduce deformation, existing technologies employ the following solutions when machining supports on conventional or CNC lathes:
[0007] 1. First, machine the outer diameter φd2 0 -0.1 and thickness of the workpiece;
[0008] 2. Considering that the final wall thickness of the workpiece is only 2mm, an open-type clamping method is selected (e.g., ...). Figure 2 As shown, an inner hole of φD1+0.05 0mm is machined to reduce deformation during clamping and machining.
[0009] However, through practice, it was found that the original processing plan had the following two shortcomings, which affected the processing quality and efficiency of the products:
[0010] 1. The existing clamping sleeve 41 is an open elastic clamping sleeve. After clamping the workpiece, the outer diameter of the workpiece φd2 0 -0.1 will be subjected to radial clamping force. Furthermore, during machining, the support and positioning area between the right end face of the workpiece and the clamping sleeve is small. When turning the inner hole φD1+0.05 0 on the left end, as the hole diameter increases, the rigidity of the workpiece deteriorates, reducing the support provided by the workpiece to the open clamping sleeve. The radial clamping force of the sleeve causes the left end face to concave. After removing the clamping sleeve, the entire inner hole φD1 becomes trumpet-shaped. Simultaneously, the right end face, affected by the cutting force, will experience bending deformation of 0.2–0.7 mm. Ultimately, this results in the right end face of the machined workpiece exhibiting a thickness that is thicker in the middle and thinner at the outer edge, failing to guarantee the dimensional requirements of the part in the drawing. Figure 3 and Figure 4 As shown.
[0011] 2. Since there is no support point in the center of the right end face of the workpiece, in order to reduce the deformation of the workpiece caused by the cutting force, a large radial clamping force cannot be selected when clamping, and a large cutting depth cannot be selected when turning (the actual cutting depth is 0.1mm), so the machining efficiency is low.
[0012] It is evident that using existing processing methods to process workpieces results in processing quality that cannot meet the requirements of the drawings, and the processing efficiency is low, making it unsuitable for the needs of mass production. Utility Model Content
[0013] The purpose of this invention is to provide a fixture to prevent deformation of thin-walled nylon disc-shaped parts during turning, which solves the technical problem of deformation when turning thin-walled nylon disc-shaped parts on ordinary lathes or CNC lathes, and at the same time greatly improves the processing efficiency of the product and meets the needs of mass production.
[0014] This utility model is achieved using the following technical solution:
[0015] A fixture for preventing deformation during turning of thin-walled nylon disc-shaped parts includes a fixture body, a fixture cover, and a fixture sheet-like clamping plate. The fixture body includes a clamping cylinder, a supporting cylinder, and a central cylinder. One side of the central cylinder is the clamping cylinder, and the other side is the supporting cylinder. The diameters of the clamping cylinder and the supporting cylinder are smaller than those of the central cylinder. The central cylinder has external threads on its cylindrical surface. The fixture cover is an annular cylinder. One side of the fixture cover has an internal thread, and the other side has an inwardly tapering opening. The inner diameter of the unthreaded portion of the fixture cover is smaller than the inner diameter of the threaded portion, which is larger than the inner diameter of the inwardly tapering opening. The fixture sheet-like clamping plate has a clamping column on one side and a chuck cylinder on the other side.
[0016] In application, after machining a chuck on the right end face of the workpiece, first machine the inner hole (e.g., Figure 8 (As shown), then use the fixture body and fixture plate clamping plate to clamp the workpiece (such as...) Figure 9As shown), the outer diameter of the workpiece is machined, and finally the workpiece is clamped using the fixture body and fixture cover (as shown). Figure 10 As shown in the figure, the workpiece chuck is removed to complete the turning of the nylon thin-walled disc-shaped part.
[0017] More preferably, the diameter of the supporting cylinder is equal to the inner hole of the workpiece to be processed, which facilitates the supporting cylinder to provide radial support and positioning for the inner hole of the workpiece, and further protects the inner hole of the workpiece.
[0018] More preferably, the chuck cylinder has a center hole from the outer surface inward, which facilitates the clamping of the workpiece by means of the tailstock and the live center.
[0019] More preferably, the cylindrical surface of the accessory cover is provided with symmetrical locking holes, which facilitates the locking of the internal thread of the accessory cover with the external thread of the accessory body.
[0020] More preferably, the outer cylindrical surface of the accessory cover is provided with a textured surface to increase the friction when the accessory cover is screwed into the accessory body.
[0021] More preferably, the auxiliary fixture body is provided with an exhaust hole that passes through the clamping cylinder, the supporting cylinder and the intermediate cylinder. The exhaust hole facilitates the installation of the auxiliary fixture body and the inner hole of the workpiece.
[0022] More preferably, the vent is located at an off-center position on the auxiliary fixture body to prevent a bulge from appearing at the center of the end face when machining the workpiece clamp.
[0023] More preferably, the number of vent holes is at least one.
[0024] By analyzing the product structure and material properties, in order to improve the processing efficiency, reduce workpiece deformation, and ensure processing quality, this utility model avoids workpiece deformation caused by cutting force during processing. This utility model changes the existing workpiece clamping method. Attached Figure Description
[0025] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with the present invention and, together with the description, serve to explain the principles of the present invention.
[0026] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0027] Figure 1 This is a schematic diagram of the workpiece.
[0028] Figure 2 This diagram illustrates the existing clamping method.
[0029] Figure 3 This diagram illustrates the problem caused by the existing clamping method. Figure 1 .
[0030] Figure 4 This diagram illustrates the problem caused by the existing clamping method. Figure 2 .
[0031] Figure 5 This is a schematic diagram of the assistive device body structure of this utility model.
[0032] Figure 6 This diagram shows the structure of the auxiliary cover of this utility model.
[0033] Figure 7 This diagram illustrates the sheet-like compression structure of the assistive device of this utility model.
[0034] Figure 8 This is a schematic diagram showing that the workpiece of this utility model has a clamp.
[0035] Figure 9 This diagram shows the workpiece clamping method for machining the outer diameter of the workpiece according to this utility model.
[0036] Figure 10 This diagram illustrates the clamping of the workpiece chuck in this invention.
[0037] In the diagram: 1-Auxiliary fixture body, 11-Clamping cylinder, 12-Supporting cylinder, 13-Intermediate cylinder, 131-External thread, 2-Auxiliary fixture cover, 21-Internal thread, 22-Inward closing, 23-Locking hole, 3-Auxiliary fixture sheet, 31-Pressure column, 32-Chuck cylinder, 321-Center hole, 4-Workpiece. Detailed Implementation
[0038] To better understand the above-mentioned objectives, features, and advantages of this utility model, the solution of this utility model will be further described below. It should be noted that, unless otherwise specified, the embodiments of this utility model and the features thereof can be combined with each other.
[0039] In this description, it should be noted that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. It should also be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joint" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms according to the specific circumstances.
[0040] Many specific details are set forth in the following description in order to provide a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein; obviously, the embodiments in the specification are only some embodiments of the present invention, and not all embodiments.
[0041] The specific embodiments of this utility model will now be described in detail with reference to the accompanying drawings.
[0042] A fixture for preventing deformation of thin-walled nylon disc-shaped parts during turning includes a fixture body 1, a fixture cover 2, and a fixture sheet-like pressure plate 3. The fixture body 1 includes a clamping cylinder 11, a supporting cylinder 12, and a middle cylinder 13. One side of the middle cylinder 13 is the clamping cylinder 11, and the other side is the supporting cylinder 12. The diameters of the clamping cylinder 11 and the supporting cylinder 12 are smaller than those of the middle cylinder 13. The cylindrical surface of the middle cylinder 13 is provided with external threads 131. The fixture cover 2 is an annular cylinder. One side of the fixture cover 2 has an opening with internal threads 21, and the other side has an opening with an inwardly narrowing opening 22. The inner diameter of the unthreaded part of the fixture cover 2 is smaller than the inner diameter of the threaded part, which is larger than the inner diameter of the inwardly narrowing opening. The fixture sheet-like pressure plate 3 has a pressure column 31 on one side and a chuck cylinder 32 on the other side.
[0043] The diameter of the supporting cylinder 12 is equal to the inner hole of the workpiece 4 to be processed.
[0044] The chuck cylinder 32 has a center hole 321 facing inward from the outer surface.
[0045] The auxiliary cover 2 has symmetrical locking holes 23 on its cylindrical surface facing inward.
[0046] The outer cylindrical surface of the auxiliary cover 2 is provided with a mesh pattern.
[0047] The auxiliary body 1 is provided with an exhaust hole that passes through the clamping cylinder 11, the supporting cylinder 12 and the intermediate cylinder 13.
[0048] The vent is located off-center from the main body of the auxiliary device 1.
[0049] The number of vents must be at least one.
[0050] During implementation, after machining a 10mm long chuck on the right end face of workpiece 4, machine an inner hole of φD1+0.05 0mm (e.g. Figure 8 (As shown), then use the auxiliary body 1 and the auxiliary sheet-like clamping plate 3 to clamp the workpiece 4 (such as...). Figure 9 As shown), the outer diameter φd2 is machined to 0.1mm. Finally, the workpiece 4 is clamped using the auxiliary fixture body 1 and the auxiliary fixture cover 2 (as shown). Figure 10 As shown), the workpiece is removed by machining the 4 chucks.
[0051] The working principle is as follows:
[0052] 1. The addition of the right end face chuck to workpiece 4 is to enhance the rigidity of workpiece 4 and reduce the end face deformation caused by excessive cutting force when turning the bottom surface of the φD1+0.05 0mm inner hole.
[0053] 2. Directly clamp the right end face of workpiece 4 with a 10mm chuck and machine the inner hole φD1+0.05 0mm. This can avoid the radial clamping force acting on the inner hole φD1+0.05 0mm of workpiece 4, and prevent the inner hole φD1 from being flared after machining, as well as the phenomenon of the 2mm wall thickness being thin near the end face and thick at the root.
[0054] 3. Positioning is achieved using surface B of the auxiliary fixture body 1 and the outer circle φd1-0.01 -0.03 (e.g., Figure 9 As shown), the end face of the inner hole φD1+0.05 0mm of the workpiece 4 is tightly attached to the B surface of the auxiliary body 1.
[0055] 4. Using the center hole 321 of the auxiliary plate 3 and the tailstock live center, press the workpiece 4 against the chuck end face, so that the end face of the inner hole φD1+0.05 0mm of the workpiece 4 is tightly against the B surface of the auxiliary body 1 (e.g., Figure 9 As shown), the outer diameter φd2 0 -0.1mm is machined without radial clamping force, which can reduce the deformation of the inner hole and the outer diameter;
[0056] 5. The design of the auxiliary pressure cover 2 ensures that there is a support point when the right end of the workpiece 4 is chucked, which can reduce the deformation of the workpiece 4 during the processing, and the cutting depth can reach 0.5~1mm. In this embodiment, φD3=φD1-10mm.
[0057] The specific operation steps in this embodiment are as follows:
[0058] 1) First, machine the right end of the workpiece 4, then clamp the φd4 chuck and machine the inner hole of workpiece 4, φD1 + 0.050mm, controlling the total length of workpiece 4 to 16mm. Chuck φd4 = φD1 + 0.050mm - 15mm (e.g., ...). Figure 8 (as shown)
[0059] 2) Before removing the bracket chuck, first use a four-jaw chuck to clamp the outer circle of the auxiliary fixture body 1φd3 (see...). Figure 5 (Schematic diagram of assistive device body 1), then use a dial indicator to align surface B and the outer circle φd1-0.01-0.03, so that the dial indicator jump is less than 0.02mm;
[0060] 3) Place workpiece 4 ( Figure 9 and Figure 10 As shown in the figure, it is installed on the auxiliary body 1 and positioned by the B surface and the outer circle of φd1-0.01-0.03 on the auxiliary body 1;
[0061] 4) The auxiliary plate-shaped clamping plate 3 uses the tailstock and center to press the workpiece 4 clamping end face ( ). Figure 9 As shown in the figure, make the inner end face of the inner hole φD1+0.05 0 of the workpiece 4 tightly fit the body surface B, and machine the outer circle φd2 0 -0.1mm.
[0062] 5) Remove the tailstock live center and the auxiliary plate 3. Then, connect the auxiliary cover 2 with the M140×1.5 thread and screw the auxiliary cover 2 onto the auxiliary body 1. Use the bottom stepped end face of the inner hole of the auxiliary cover 2 φD2+0.05 0 to press the workpiece 4 against the left end face of the machined chuck. Figure 10 As shown in the figure, after the inner end face of the inner hole φD1+0.05 0 of the workpiece 4 is tightly attached to the surface of the auxiliary body 1B, tighten the pressure cap to press the workpiece 4.
[0063] 6) Remove the 4 chucks from the workpiece and connect them with... Figure 1 In the attached diagram, surface A is flush with the workpiece to complete the machining of the right end face of workpiece 4;
[0064] 7) Unscrew the auxiliary cover 2, remove the processed workpiece 4, reinstall workpiece 4, and then process the next workpiece 4.
[0065] Compared with the existing technology for processing workpiece 4, it has the following processing advantages:
[0066] 1) By adding a process chuck and using the inner hole and inner hole end face of workpiece 4 for positioning and machining, there are support points on both ends when turning the bottom surface of the φD1+0.05 0mm inner hole with the worst rigidity and the right end face of workpiece 4, which enhances the rigidity of workpiece 4. Furthermore, larger cutting parameters (depth of cut and feed rate) can be selected during machining, and the machining efficiency can be improved by 5-10 times.
[0067] 2) By using process chucks and axial clamping, the influence of radial clamping force on workpiece 4 is reduced, effectively controlling the deformation of workpiece 4 caused by clamping force and cutting force, and ensuring that the dimensional requirements of the product drawings are met.
[0068] 3) After aligning the automotive auxiliary tool once using a dial indicator, multiple workpieces can be processed 4, without the need to repeatedly align the workpieces 4 using a dial indicator;
[0069] 4) This machining scheme also provides a good reference for the turning of other workpieces 4 with poor rigidity and low strength.
[0070] This invention provides a convenient, economical, efficient, and reliable machining method for thin-walled nylon disc-shaped parts on ordinary lathes or CNC lathes, suitable for mass production.
[0071] The above description is merely a specific embodiment of this utility model, enabling those skilled in the art to understand or implement it. Although detailed descriptions have been provided with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments, and all should be covered by the protection scope of the claims.
Claims
1. A fixture for preventing deformation of a thin-walled nylon disc-like part during turning, characterized by: The device includes an auxiliary body (1), an auxiliary cover (2), and an auxiliary sheet-shaped pressure plate (3). The auxiliary body (1) includes a clamping cylinder (11), a supporting cylinder (12), and a middle cylinder (13). The middle cylinder (13) has a clamping cylinder (11) on one side and a supporting cylinder (12) on the other side. The diameters of the clamping cylinder (11) and the supporting cylinder (12) are smaller than those of the middle cylinder (13). The cylindrical surface of the middle cylinder (13) is provided with an external thread (131). The auxiliary cover (2) is an annular cylinder. The auxiliary cover (2) has an opening with an internal thread (21) on one side and an opening with an inward closing opening (22) on the other side. The inner diameter of the unthreaded part of the auxiliary cover (2) is smaller than that of the threaded part, which is larger than the inner diameter of the inward closing opening. The auxiliary sheet-shaped pressure plate (3) has a pressure column (31) on one side and a clamping cylinder (32) on the other side.
2. The fixture for preventing deformation of a thin-walled nylon disc-shaped part during turning according to claim 1, wherein: The diameter of the supporting cylinder (12) is equal to the inner hole of the workpiece (4) to be processed.
3. The fixture of claim 1, wherein: The chuck cylinder (32) has a top hole (321) facing inward from the outer surface.
4. The fixture of claim 1, wherein: The auxiliary cover (2) has symmetrical locking holes (23) on its cylindrical surface facing inward.
5. A fixture for preventing deformation during turning of thin-walled nylon disc-shaped parts according to claim 1, characterized in that: The outer cylindrical surface of the auxiliary cover (2) is provided with a mesh pattern.
6. The fixture of any one of claims 1-5, wherein: The auxiliary body (1) is provided with an exhaust hole that passes through the clamping cylinder (11), the supporting cylinder (12) and the intermediate cylinder (13).
7. The fixture of claim 6, wherein: The vent is located at an off-center position on the auxiliary body (1).
8. The fixture of claim 7, wherein: The number of exhaust ports is at least one.