A displacement processing method and tooling for elliptical inner cavity special-shaped parts

Abstract

The present invention relates to a displacement processing method for elliptical inner cavity special-shaped parts, which comprises the following steps: turning the elliptical inner cavity of the workpiece into a rotating body according to the minor axis size of the ellipse; rotating the axis of the workpiece to a set angle with the main axis direction of the machine tool, and removing the amount of the side wall of the elliptical inner cavity of the workpiece in the major axis direction by a milling cutter following a predetermined trajectory; using an arc cutter to perform contour processing according to the shape of the elliptical inner cavity of the workpiece; processing a process hole on the end face of the workpiece, and installing a displacement tool through the process hole; aligning the shape of the displacement tool, and processing the shape of the workpiece along the axial direction of the workpiece. The process is simple and reasonable, easy to operate, and can be processed and formed in one step. It can realize the shape processing of special-shaped parts and produce products that usually require a five-axis machine tool to manufacture; the processing method of the outer shape and the inner cavity can reduce tool wear and improve processing efficiency while ensuring that the same coordinate system is used inside and outside.

Description

Technical Field

[0001] The present invention relates to the field of mechanical processing technology, and in particular to a displacement processing method and tooling for an elliptical inner cavity special-shaped part. Background Art

[0002] The machining of irregularly shaped parts with elliptical internal cavities is challenging, especially for those with elliptical inner and outer cavities and high surface quality requirements. These parts are typically processed using five-axis machining centers or milling / turning centers. Five-axis machining allows for both rough and finish machining of parts in a single setup, reducing setup times while ensuring product quality. If you need to quickly and accurately machine irregularly shaped parts, a five-axis machine is undoubtedly a reliable and convenient option. However, given the high cost of these machines, purchasing such high-precision tools specifically for a particular irregular part is extremely cost-effective and generally not an option for businesses. However, using conventional boring and milling machines with general-purpose fixtures is difficult because positioning and clamping the workpiece is challenging, and clamping can easily cause deformation, resulting in issues with surface quality and dimensions. Summary of the Invention

[0003] (1) Technical issues to be resolved

[0004] In view of the above-mentioned shortcomings and deficiencies of the prior art, the present invention provides a displacement processing method and tooling for elliptical inner cavity special-shaped parts, which solves the technical problem that ordinary boring and milling machines are difficult to process special-shaped elliptical inner cavity parts.

[0005] (2) Technical solution

[0006] In order to achieve the above-mentioned object, the displacement processing method of the elliptical inner cavity special-shaped part of the present invention comprises:

[0007] S1. The elliptical inner cavity of the workpiece is turned into a rotational body according to the minor axis size of the ellipse;

[0008] S2. Rotate the axis of the workpiece to form a set angle with the main axis direction of the machine tool, and remove the side wall of the elliptical inner cavity of the workpiece in the long axis direction by using the milling cutter to follow a predetermined trajectory;

[0009] S3, using a circular cutter to perform profiling according to the shape of the elliptical inner cavity of the workpiece;

[0010] S4. Processing a process hole on the end face of the workpiece and installing a displacement tool through the process hole;

[0011] S5. Align the shape of the displacement tooling and process the shape of the workpiece along the axial direction of the workpiece.

[0012] Optionally, the elliptical inner cavity of the workpiece is turned according to the size of the minor axis, and the outer shape of the workpiece is turned according to the size of the major axis. After the processing is completed, it is a rotating body, and a processing allowance of 1-3 mm is left on one side;

[0013] At the end of the workpiece, use a T-type cutter to turn the elliptical inner cavity contour into place, and the processing distance is S;

[0014] The angle between the workpiece and the main axis of the machine tool is adjusted according to the eccentricity of the elliptical inner cavity of the workpiece, and the machining allowance in the long axis direction of the elliptical inner cavity is removed by using a milling cutter.

[0015] Optionally, the elliptical inner cavity of the workpiece is roughly machined into place along the contour trajectory in a spiral feed manner.

[0016] Optionally, the angle between the machine tool spindle and the axis of the workpiece is determined according to the tool size, machining allowance, hole size, and the depth of the elliptical cavity of the same elliptical trajectory, and the angle is α;

[0017] The workpiece is translated simultaneously in the X and Z directions, and the tool rotates with the machine spindle and mills a circle on the section perpendicular to the machine spindle. α satisfies:

[0018]

[0019] Wherein, L is the depth of the elliptical cavity, d is the diameter of the tool, M is the opening width of the elliptical cavity at the end face of the workpiece, and e is the eccentricity of the elliptical cavity;

[0020] H=S+L; where H is the depth of the workpiece cavity;

[0021] The diameter of the circle milled by the tool is R, and R satisfies:

[0022]

[0023] Where a is half of the major axis of the elliptical cavity.

[0024] Optionally, the process hole includes two positioning holes and a plurality of threaded holes;

[0025] The major axis of the cross axis of the elliptical inner cavity is taken as the 0-180° line, and the central axes of the two pin holes intersect the 0-180° line perpendicularly.

[0026] Optionally, positioner fixtures are installed on both ends of the workpiece, and the workpiece is mounted on the machine tool in such a way that the length direction of the workpiece is perpendicular to the machine tool spindle. The machine tool spindle moves in the axial direction of the workpiece to process the workpiece shape within the set angle range. After processing, the workpiece is rotated to the set angle, and the axial direction of the workpiece is corrected before continuing processing. This is repeated until the workpiece shape is roughly processed in place.

[0027] Among them, the displacement tooling includes two positioning blocks respectively used to connect the two ends of the elliptical special-shaped parts. The positioning blocks are all regular polygonal or circular. There are multiple lightening holes, multiple through holes and multiple pin holes on the positioning blocks. The multiple lightening holes, multiple through holes and multiple pin holes are evenly arranged with the symmetry center of the positioning blocks; two of the multiple pin holes correspond one-to-one to the two positioning holes and are connected by pins, and the multiple threaded holes correspond one-to-one to the multiple through holes and are connected by screws.

[0028] Optionally, after step S5, the method further includes: performing heat treatment on the processed workpiece.

[0029] Optionally, after the workpiece is heat treated, the deformation of the workpiece is measured, and the cross axis of the elliptical inner cavity of the workpiece is corrected with reference to the process hole left on the end face by rough processing. The inner cavity of the workpiece is face milled using the method of step S2 to remove the machining amount in the heat treatment deformation area. The elliptical inner cavity is fine-machined into place by performing multiple passes according to the shape of the elliptical inner cavity.

[0030] Optionally, after the elliptical inner cavity is processed, the process hole on the end face is trimmed, and conversion tooling is installed at both ends. The method of step S5 is used to fine-tune the shape of one half side. After the processing is completed, the tooling is flipped 180°, and the method of step S5 is continued to be used to fine-tune the shape of the other half side.

[0031] Optionally, after the workpiece shape is finely machined, the workpiece is raised from the middle using a contouring tool, and the process heads at both ends are milled.

[0032] (3) Beneficial effects

[0033] The process is simple and reasonable, easy to operate, and can be formed in one step. It can realize the shape processing of special-shaped parts and produce products that usually require five-axis machine tools. The processing method of the outer shape and the inner cavity can reduce tool wear and improve processing efficiency while ensuring the same coordinate system inside and outside. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 This is a flow chart of the displacement processing method of the elliptical inner cavity special-shaped part of the present invention;

[0035] Figure 2 Schematic diagram of step 2 of the displacement processing method for an elliptical inner cavity special-shaped part according to the present invention;

[0036] Figure 3 Schematic diagram of tool milling circle in the displacement processing method of the elliptical inner cavity special-shaped part of the present invention;

[0037] Figure 4 Schematic diagram of step 3 of the displacement processing method for an elliptical inner cavity special-shaped part according to the present invention;

[0038] Figure 5 Schematic diagram of workpiece shape finishing of the displacement processing method of the elliptical inner cavity special-shaped part of the present invention;

[0039] Figure 6 This is a front view of a displacement tool for the displacement processing method of an elliptical inner cavity special-shaped part of the present invention;

[0040] Figure 7 It is a side view of the displacement tooling of the displacement processing method of the elliptical inner cavity special-shaped part of the present invention.

[0041] [Description of Reference Numerals]

[0042] 1: workpiece;

[0043] 2: Machine tool spindle;

[0044] 3: Displacement tooling; 31: Lightening hole; 32: Through hole; 33: Pin hole. DETAILED DESCRIPTION

[0045] In order to better explain the present invention and facilitate understanding, the present invention is described in detail below through specific implementation methods in conjunction with the accompanying drawings.

[0046] Although exemplary embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to enable a clearer and more thorough understanding of the present invention and to fully convey the scope of the present invention to those skilled in the art.

[0047] like Figure 1-7 As shown, the present invention provides a displacement processing method for an elliptical inner cavity special-shaped part, which includes the following steps:

[0048] Step 1: The elliptical inner cavity of the workpiece 1 is turned into a body of revolution according to the length of the minor axis of the ellipse. The elliptical inner cavity of the workpiece 1 refers to the shape of the inner cavity in the cross section of the workpiece 1 being elliptical.

[0049] Step 2: Rotate the axis of the workpiece 1 to form a set angle with the direction of the machine tool spindle 2, and remove the side wall of the elliptical inner cavity of the workpiece 1 in the long axis direction by using the milling cutter to follow a predetermined trajectory, and the predetermined trajectory is set according to the shape of the elliptical inner cavity;

[0050] Step 3: After removing the amount of the side wall of the elliptical cavity in the long axis direction, use a circular arc cutter to further contour the shape of the elliptical cavity of the workpiece 1 to improve the accuracy of the elliptical cavity;

[0051] Step 4: After the elliptical inner cavity is processed, the outer shape of the workpiece 1 is processed. Before processing, multiple process holes are processed on the end faces of both ends of the workpiece 1, and the displacement tooling 3 is installed at both ends of the workpiece 1 through the process holes;

[0052] Step 5: Install the workpiece 1 on the machine tool through the positioner 3, align the shape of the positioner 3 so that the axial direction of the workpiece 1 coincides with the axial direction of the machine tool, and machine the shape of the workpiece 1 along the axial direction of the workpiece 1.

[0053] The process is simple and reasonable, easy to operate, and can be formed in one step. It can realize the shape processing of special-shaped parts and produce products that usually require five-axis machine tools. The processing method of the outer shape and the inner cavity can reduce tool wear and improve processing efficiency while ensuring the same coordinate system inside and outside.

[0054] Furthermore, in step one, a blind hole much smaller than the short axis of the inner cavity is first processed with a deep hole drill for quick measurement; then the inner cavity and the outer shape are turned and formed on a machine tool, the inner cavity is cut according to the short axis section, and the outer shape is cut according to the long axis section; after processing, the workpiece 1 is a rotating body, and a single side of the workpiece 1 is reserved with a processing allowance of 1-3mm to ensure the processing allowance for subsequent milling.

[0055] At the end of workpiece 1, a T-shaped tool is used to turn the elliptical inner cavity contour into place, with a processing distance of S. A section of the bottom is pre-processed into place to ensure that there is no interference with the end when the subsequent tool is tilted into place.

[0056] like Figure 2 and Figure 3 As shown, the angle between the workpiece 1 and the machine tool spindle 2 is adjusted according to the eccentricity of the elliptical inner cavity of the workpiece 1, and the machining allowance in the long axis direction of the elliptical inner cavity is removed using a milling cutter. The elliptical inner cavity of the workpiece 1 is roughly machined into place along the contour trajectory using a spiral feed method.

[0057] Specifically, when selecting a milling cutter for machining, the angle between the machine tool spindle 2 and the axis of the workpiece 1 is determined based on the tool size, machining allowance, the size of the elliptical cavity opening on the end face of the workpiece 1, and the depth of the elliptical cavity along the same elliptical trajectory. The angle is α. During machining, the workpiece 1 translates simultaneously in the X and Z directions, and the cutter rotates with the machine tool spindle 2 and mills a circle on a section perpendicular to the machine tool spindle 2. α satisfies:

[0058]

[0059] Wherein, L is the depth of the elliptical cavity, d is the diameter of the tool, M is the opening width of the elliptical cavity at the end face of the workpiece 1, and e is the eccentricity of the elliptical cavity;

[0060] H=S+L;wherein, H is the depth of the cavity of workpiece 1;

[0061] The diameter of the circle milled by the tool is R, and R satisfies:

[0062]

[0063] Where a is half of the major axis of the elliptical cavity.

[0064] Furthermore, the process holes opened on the end faces of both ends of the workpiece 1 include two positioning holes and multiple threaded holes. Among them, the major axis of the cross axis of the ellipse presented by the cross section of the elliptical inner cavity is the 0-180° line, the central axis of the two pin holes 33 intersects the 0-180° line perpendicularly, and the two pin holes 33 are respectively located at both ends of the 0-180° line. The corresponding displacement fixtures 3 are installed on both ends of the workpiece 1, and the workpiece 1 is installed on the machine tool in a position where the length direction of the workpiece 1 is perpendicular to the machine tool spindle 2. The machine tool spindle 2 moves in the axial direction of the workpiece 1 to process the shape of the workpiece 1 within the set angle range. After the processing is completed, the workpiece 1 is rotated to the set angle, and the axial direction of the workpiece 1 is corrected and the processing is continued. The shape of the workpiece 1 is repeatedly rough-machined in place. In one embodiment, the machine tool spindle 2 moves in the axial direction of the workpiece 1 to process the shape within the 60° angle range. After the processing is completed, the workpiece 1 is rotated 60°, and the axial direction of the workpiece 1 is corrected and the processing is continued. This is repeated 6 times to rough-machine the shape.

[0065] like Figure 6 and Figure 7 As shown, the displacement fixture 3 includes two positioning blocks for connecting the two ends of the elliptical special-shaped part. The positioning blocks are both regular polygonal or circular. The positioning blocks are provided with multiple lightening holes 31, multiple through holes 32, and multiple pin holes 33. The multiple lightening holes 31, multiple through holes 32, and multiple pin holes 33 are evenly arranged around the symmetry center of the positioning block. Two of the multiple pin holes 33 correspond one-to-one with the two positioning holes and are connected by pins, and the multiple threaded holes correspond one-to-one with the multiple through holes 32 and are connected by screws. In one embodiment, the displacement fixture 3 is mainly composed of positioning blocks, pins, and screws. The positioning blocks are regular polygonal or circular, preferably regular hexagonal, and are provided with three different types of holes, specifically: six identical lightening holes 31 distributed on the positioning blocks; four through holes 32 smaller than the lightening holes 31 distributed on the same axis of the positioning blocks for screw connection; and eight pin holes 33 smaller than the through holes 32 distributed on the other two oblique symmetric axes of the positioning blocks for pin connection. Because the hexagonal positioning block and pin hole 33 play a primary positioning role, strict requirements are placed on the surface profile and surface roughness of the positioning block, as well as the position and verticality of the pin hole 33, which facilitates the connection and positioning of the tooling. However, the position requirements for the through hole 32 are not as high. The present invention uses a displacement tool 3 to process elliptical products. The structure is reasonable and the positioning is precise. Only a few flips of the processing displacement tool 3 are required to process the special-shaped part, producing a product that usually requires a five-axis machine tool. The use of the displacement tool 3 can save companies a huge amount of hardware equipment investment costs.

[0066] After step five, the following steps are also included:

[0067] Step 6: heat-treating the processed workpiece 1 to reduce the strength of the workpiece 1;

[0068] Step 7: After the heat treatment of the workpiece 1 is completed, the deformation of the workpiece 1 is measured, and the cross axis of the elliptical inner cavity of the workpiece 1 is corrected with reference to the process hole left on the end face by rough processing. If the elliptical inner cavity is deformed, the workpiece 1 is mounted on the machine tool. After the workpiece 1 is aligned, the workpiece 1 is set at an angle to the main axis in the length direction, and the inner cavity of the workpiece 1 is face milled using the method of step S2 to remove the machining amount of the heat treatment deformation area, reduce the loss of tool processing, and pass the tool 3-4 times according to the shape of the elliptical inner cavity to fine-machine the elliptical inner cavity into place;

[0069] Step 8: After the elliptical inner cavity is processed, the process hole of the end face is trimmed, the pin hole 33 is enlarged, and conventional small conversion tooling is installed at both ends. Figure 5 After finishing the shape of one half of the side by the method of step S5, the tool is turned 180 degrees and the shape of the other half of the side is finished by the method of step S5;

[0070] Step 9: After the shape of the workpiece 1 is finely machined, the workpiece 1 is raised from the middle using a contour tool, and the process heads at both ends are milled.

[0071] The process of the present invention is simple and reasonable, easy to operate, and can be processed and formed in one step. It can realize the shape processing of special-shaped parts and produce products that usually require five-axis machine tools to manufacture; the processing method of the outer shape and the inner cavity can reduce tool wear and improve processing efficiency while ensuring the same coordinate system inside and outside.

[0072] In the description of the present invention, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of the technical features indicated. Therefore, a feature specified as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, "plurality" means two or more, unless otherwise specifically defined.

[0073] In the present invention, unless otherwise expressly specified or limited, the terms "mounted," "connected," "connect," "fixed," etc. should be understood broadly. For example, they may refer to fixed connection, detachable connection, or integration; mechanical connection or electrical connection; direct connection or indirect connection through an intermediate medium; and internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0074] In the present invention, unless otherwise expressly specified or limited, when a first feature is "above" or "below" a second feature, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Furthermore, when a first feature is "above," "above," or "above" a second feature, it may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is "below," "below," or "below" a second feature, it may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0075] In the description of this specification, the terms "one embodiment", "some embodiments", "embodiments", "examples", "specific examples" or "some examples" refer to the specific features, structures, materials or characteristics described in conjunction with the embodiment or example and included in at least one embodiment or example of the present invention. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine different embodiments or examples described in this specification and features of different embodiments or examples, unless they are mutually inconsistent.

[0076] Although the embodiments of the present invention have been shown and described above, it will be understood that the above embodiments are illustrative and are not to be construed as limitations on the present invention. A person skilled in the art may alter, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A displacement processing method for an elliptical inner cavity special-shaped part, characterized in that: The displacement processing methods of elliptical inner cavity special-shaped parts include: S1. The elliptical inner cavity of the workpiece is turned into a rotational body according to the minor axis size of the ellipse; S2. Rotate the axis of the workpiece to form a set angle with the main axis direction of the machine tool, and remove the side wall of the elliptical inner cavity of the workpiece in the long axis direction by using the milling cutter to follow a predetermined trajectory; S3, using a circular cutter to perform profiling according to the shape of the elliptical inner cavity of the workpiece; S4. Processing a process hole on the end face of the workpiece and installing a displacement tool through the process hole; S5. Align the shape of the displacement tooling and process the shape of the workpiece along the axial direction of the workpiece.

2. The displacement processing method of the elliptical inner cavity special-shaped part according to claim 1, characterized in that: The elliptical inner cavity of the workpiece is turned according to the size of the minor axis, and the outer shape of the workpiece is turned according to the size of the major axis. After processing, it is a rotating body with a processing allowance of 1-3mm on one side; At the end of the workpiece, use a T-type cutter to turn the elliptical inner cavity contour into place, and the processing distance is S; The angle between the workpiece and the main axis of the machine tool is adjusted according to the eccentricity of the elliptical inner cavity of the workpiece, and the machining allowance in the long axis direction of the elliptical inner cavity is removed by using a milling cutter.

3. The displacement processing method of the elliptical inner cavity special-shaped part according to claim 2, characterized in that: The elliptical inner cavity of the workpiece is roughly machined into place according to the contour trajectory in a spiral feed manner.

4. The displacement processing method of the elliptical inner cavity special-shaped part according to claim 3, characterized in that: The included angle between the machine tool spindle and the workpiece axis is determined according to the tool size, machining allowance, hole size, and the depth of the elliptical cavity of the same elliptical trajectory. The included angle is α. The workpiece is translated simultaneously in the X and Z directions, and the tool rotates with the machine spindle and mills a circle on the section perpendicular to the machine spindle. α satisfies: Wherein, L is the depth of the elliptical cavity, d is the diameter of the tool, M is the opening width of the elliptical cavity at the end face of the workpiece, and e is the eccentricity of the elliptical cavity; H=S+L; where H is the depth of the workpiece cavity; The diameter of the circle milled by the tool is R, and R satisfies: Where a is half of the major axis of the elliptical cavity.

5. The displacement processing method of an elliptical inner cavity special-shaped part according to claim 1, characterized in that: The process holes include two positioning holes and multiple threaded holes; The major axis of the cross axis of the elliptical inner cavity is taken as the 0-180° line, and the central axes of the two pin holes intersect the 0-180° line perpendicularly.

6. The displacement processing method of an elliptical inner cavity special-shaped part according to claim 5, characterized in that: Install the positioner on both ends of the workpiece, and install the workpiece on the machine tool in a way that the length direction of the workpiece is perpendicular to the machine tool spindle. The machine tool spindle moves in the axial direction of the workpiece to process the workpiece shape within the set angle range. After processing, rotate the workpiece to the set angle, correct the axial direction of the workpiece and continue processing. Repeat this process until the workpiece shape is roughly processed in place. Among them, the displacement tooling includes two positioning blocks respectively used to connect the two ends of the elliptical special-shaped parts. The positioning blocks are all regular polygonal or circular. There are multiple lightening holes, multiple through holes and multiple pin holes on the positioning blocks. The multiple lightening holes, multiple through holes and multiple pin holes are evenly arranged with the symmetry center of the positioning blocks; two of the multiple pin holes correspond one-to-one to the two positioning holes and are connected by pins, and the multiple threaded holes correspond one-to-one to the multiple through holes and are connected by screws.

7. The displacement processing method of an elliptical inner cavity special-shaped part according to claim 1, characterized in that: After step S5, the following further steps are performed: heat treatment is performed on the processed workpiece.

8. The displacement processing method of an elliptical inner cavity special-shaped part according to claim 7, characterized in that: After the workpiece is heat treated, the deformation of the workpiece is measured. The cross axis of the elliptical inner cavity of the workpiece is corrected with reference to the process hole left on the end face by rough machining. The inner cavity of the workpiece is face milled using the method of step S2 to remove the machining amount in the heat treatment deformation area. The elliptical inner cavity is fine-machined into place in multiple passes according to the shape of the elliptical inner cavity.

9. The displacement processing method of an elliptical inner cavity special-shaped part according to claim 8, characterized in that: After the elliptical inner cavity is processed, the process hole on the end face is trimmed, and the conversion tooling is installed at both ends. The method of step S5 is used to fine-tune the shape of one half side. After processing is completed, the tooling is turned 180°, and the method of step S5 is continued to be used to fine-tune the shape of the other half side.

10. The displacement processing method of an elliptical inner cavity special-shaped part according to claim 9, characterized in that: After the workpiece shape is finely machined, the workpiece is raised from the middle using a contouring tool, and the process heads at both ends are milled.

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