Clamping tool for finish machining of workpiece appearance and machining method

Abstract

The invention provides a clamping tool for finish machining of the appearance of a workpiece and a machining method, and belongs to the technical field of machining. The problems that in the prior art, four faces of the periphery of a workpiece cannot be machined and formed at a time, and it is guaranteed that the profile tolerance of the workpiece meets design indexes are solved. A tool base comprises a second bearing, a fixed base and a tool installation base, the tool installation base is horizontally fixed to the surface of a machine tool, the fixed base is of a U-shaped structure, a through hole is formed in a bottom plate, the fixed bottom plate is installed on a cylindrical protrusion of the tool installation base in a sleeving mode through the second bearing, and a threaded hole is formed in the upper surface of a side plate of the fixed base; the tool top cover comprises a first bearing, a gland, a top cover shaft and a screw, a center hole is formed in the middle of the gland, the gland is coaxially connected with the top cover shaft through the first bearing, and the gland is connected with the threaded hole in the fixed base through the screw. The problems that in the prior art, the four faces of the periphery of a workpiece cannot be machined and formed at a time, and it is guaranteed that the profile tolerance of the workpiece meets design indexes are solved.

Description

Technical Field

[0001] This invention relates to the field of machining technology, and in particular to a clamping fixture and machining method for precision machining of workpiece shape. Background Technology

[0002] In mechanical design, some high-precision mounting blocks require individual machining and small-clearance fit design. Therefore, the workpiece's external shape accuracy is critical, ensuring a contour tolerance of less than 0.03mm on all four sides and a perpendicularity to the bottom surface of less than 0.03mm. Conventional machining typically employs the following two methods:

[0003] Method 1: Using clamping plates, first process two diagonal straight edges, then use a series of clamping plates to process the other two straight edges to ensure the workpiece's external dimensions.

[0004] Method 2: The bottom surface of the workpiece is bonded with adhesive, allowing the workpiece to be clamped in one go, and the outer shape is processed by a single CNC machining program.

[0005] The existing technology has the following drawbacks: Method 1 requires a series of pressing plates, during which the workpiece is prone to movement, resulting in joints in the shape processing and thus causing the contour to exceed the tolerance; Method 2 requires adhesive bonding and adhesive removal time, resulting in poor workpiece processing smoothness and slow overall progress.

[0006] In summary, there is an urgent need to propose a clamping fixture and machining method for precision machining of workpiece shapes, in order to solve the problem that the four sides of the workpiece cannot be machined in one go in the existing technology, and to ensure that the outline of the workpiece meets the design specifications. Summary of the Invention

[0007] A brief overview of the invention is given below to provide a basic understanding of certain aspects of it. It should be understood that this overview is not an exhaustive summary of the invention. It is not intended to identify key or essential parts of the invention, nor is it intended to limit the scope of the invention. Its purpose is merely to present certain concepts in a simplified form as a prelude to the more detailed description that follows.

[0008] In view of this, in order to solve the problem that the four sides of a workpiece cannot be machined in one go in the prior art and to ensure that the outline of the workpiece meets the design specifications, the present invention provides a clamping fixture and machining method for precision machining of the workpiece outline.

[0009] Option 1: A clamping fixture for precision machining of workpiece shape, comprising a fixture base and a fixture top cover;

[0010] The tooling base includes a second bearing, a fixed base, and a tooling mounting base. The tooling mounting base is horizontally fixed on the machine tool surface. The upper surface of the tooling mounting base is provided with a cylindrical protrusion. The fixed base has a U-shaped structure and a through hole on the base plate. The fixed base plate is mounted on the cylindrical protrusion of the tooling mounting base through the second bearing. The upper surface of the side plate of the fixed base is provided with a threaded hole.

[0011] The tooling top cover includes a first bearing, a pressure cover, a top cover shaft, and screws. The pressure cover has a central hole in the middle. The pressure cover is coaxially connected to the top cover shaft through the first bearing. The pressure cover is connected to the threaded hole on the fixed base through screws.

[0012] Furthermore, the second bearing and the cylindrical protrusion of the tooling mounting base, as well as the first bearing and the top cover shaft, are both interference fits.

[0013] Option 2: A method for machining the outer shape of a workpiece for precision machining, which is accomplished using the clamping fixture for precision machining of the outer shape of a workpiece as described in Option 1, specifically including the following steps:

[0014] S1. Place the tooling mounting base horizontally on the machine tool surface and tighten it with screws. Check that the flatness of the upper surface of the tooling mounting base is less than 0.01mm.

[0015] S2. Place the workpiece on the upper surface of the fixture base, check that the flatness of the upper surface of the workpiece is less than 0.01mm, place the top cover of the fixture on the upper surface of the workpiece, and check that the fixture can rotate freely by screwing it in two places.

[0016] S3. Use UG to create a CNC machining program for milling the workpiece shape;

[0017] S4. Machining the workpiece shape: During the process of machining the workpiece shape by executing the CNC machining program, the machine tool tool holder contacts the outer contour of the fixture to realize the function of driving the fixture to rotate, ensuring that the workpiece shape is formed in one clamping.

[0018] S5. After the workpiece is machined, remove two screws and check that the workpiece's outline is less than 0.02mm, which meets the design requirements.

[0019] The present invention has the following advantages over the prior art:

[0020] 1. This invention enables the one-time machining and forming of all four sides of a workpiece in a single clamping operation, reducing the number of clamping operations and steps, and simplifying the machining process;

[0021] 2. This invention effectively avoids problems such as clamping misalignment and splicing in the prior art, ensuring that the workpiece's outline conforms to the design specifications and meets high precision requirements;

[0022] 3. While ensuring stable product processing quality, this invention optimizes the processing flow through innovative clamping tooling, thereby significantly improving processing efficiency. Attached Figure Description

[0023] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this invention, illustrate exemplary embodiments of the invention and are used to explain the invention, but do not constitute an undue limitation of the invention. In the drawings:

[0024] Figure 1 This is a schematic diagram of a clamping fixture for precision machining of workpiece shape.

[0025] In the diagram: 1-workpiece, 2-first bearing, 3-second bearing, 4-pressure cover, 5-fixed base, 6-tool mounting seat, 7-screw, 8-top cover shaft. Detailed Implementation

[0026] To make the technical solutions and advantages of the embodiments of the present invention clearer, the exemplary embodiments of the present invention will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not an exhaustive list of all embodiments. It should be noted that, unless otherwise specified, the embodiments and features in the embodiments of the present invention can be combined with each other.

[0027] Example 1, Reference Figure 1 This embodiment describes a clamping fixture for finishing the shape of a workpiece, comprising a fixture base and a fixture top cover.

[0028] The tooling base includes a second bearing 3, a fixed base 5, and a tooling mounting base 6. The tooling mounting base 6 is horizontally fixed on the machine tool surface. The upper surface of the tooling mounting base 6 is provided with a cylindrical protrusion. The fixed base 5 has a U-shaped structure and a through hole on the base plate. The fixed base plate 5 is mounted on the cylindrical protrusion of the tooling mounting base 6 through the second bearing 3. The upper surface of the side plate of the fixed base 5 is provided with a threaded hole.

[0029] The tooling top cover includes a first bearing 2, a pressure cover 4, a top cover shaft 8, and screws 7. The pressure cover 4 has a central hole in the middle. The pressure cover 4 is coaxially connected to the top cover shaft 8 through the first bearing 2. The pressure cover 4 is connected to the threaded hole on the fixed base 5 through the screws 7.

[0030] Furthermore, the second bearing 3 and the cylindrical protrusion of the tooling mounting seat 6, and the first bearing 2 and the top cover shaft 8 are both interference fits.

[0031] Example 2, Reference Figure 1 This embodiment describes a method for machining the outer shape of a workpiece, which is accomplished using the clamping fixture described in Embodiment 1 for machining the outer shape of a workpiece.

[0032] S1. Place the tooling mounting base 6 horizontally on the machine tool surface and tighten it with screws. Check that the flatness of the upper surface of the tooling mounting base 6 is less than 0.01mm.

[0033] S2. Place workpiece 1 on the upper surface of the fixture base, check that the flatness of the upper surface of workpiece 1 is less than 0.01mm, place the fixture top cover on the upper surface of workpiece 1, and screw it in with two screws 7. Check that the fixture 1 can rotate freely.

[0034] S3. Use UG to create a CNC machining program for milling the outline of workpiece 1;

[0035] S4. Machining the outer shape of workpiece 1: During the CNC machining process of machining the outer shape of workpiece 1, the tool holder of the machining machine tool contacts the outer contour of the fixture to realize the function of driving the fixture to rotate, ensuring that the outer shape of workpiece 1 is formed in one clamping. The cutting speed and feed should not be too high to prevent the spindle from hitting the fixture with excessive force.

[0036] S5. After the workpiece 1 is processed, remove the two screws 7 and check that the outline of workpiece 1 is less than 0.02mm, which meets the design requirements.

[0037] This invention enables the one-time machining and forming of all four sides of a workpiece with a single clamping, reducing the number of clamping operations and simplifying the machining process. At the same time, it effectively avoids problems such as clamping misalignment and splicing in existing technologies, ensuring that the workpiece's outline conforms to the design specifications and meets high precision requirements.

[0038] This invention not only ensures stable product processing quality but also optimizes the processing flow through innovative clamping fixtures, thereby significantly improving processing efficiency.

[0039] Although the invention has been described with reference to a limited number of embodiments, those skilled in the art will understand from the foregoing description that other embodiments are conceivable within the scope of the invention described herein. Furthermore, it should be noted that the language used in this specification has been chosen primarily for readability and instructional purposes, and not for the purpose of interpreting or limiting the subject matter of the invention. Therefore, many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the appended claims. The disclosure of the invention is illustrative and not restrictive, and the scope of the invention is defined by the appended claims.

Claims

1. A clamping fixture for precision machining of workpiece shape, characterized in that, Includes the tooling base and the tooling top cover; The tooling base includes a second bearing (3), a fixed base (5) and a tooling mounting seat (6). The tooling mounting seat (6) is horizontally fixed on the machine tool surface. The upper surface of the tooling mounting seat (6) is provided with a cylindrical protrusion. The fixed base (5) has a U-shaped structure and a through hole on the bottom plate. The fixed base (5) is mounted on the cylindrical protrusion of the tooling mounting seat (6) through the second bearing (3). The upper surface of the side plate of the fixed base (5) is provided with a threaded hole. The tooling top cover includes a first bearing (2), a pressure cover (4), a top cover shaft (8), and screws (7). The pressure cover (4) has a central hole in the middle. The pressure cover (4) is coaxially connected to the top cover shaft (8) through the first bearing (2). The pressure cover (4) is connected to the threaded hole on the fixed base (5) through the screws (7).

2. The clamping fixture for finishing the shape of a workpiece according to claim 1, characterized in that, The second bearing (3) and the tooling mounting base (6) and the first bearing (2) and the top cover shaft (8) are both interference fit.

3. A method for machining the shape of a workpiece for precision machining, wherein the method employs the clamping fixture for precision machining of the workpiece shape as described in claim 1, characterized in that, Specifically, the following steps are included: S1. Place the tooling mounting base (6) horizontally on the machine tool surface and tighten it with screws. Check that the flatness of the upper surface of the tooling mounting base (6) is less than 0.01mm. S2. Place the workpiece (1) on the upper surface of the fixture base, check that the flatness of the upper surface of the workpiece (1) is less than 0.01mm, place the fixture top cover on the upper surface of the workpiece (1), and screw it in with two screws (7) to check that the fixture can rotate freely. S3. Compile a CNC machining program for the shape of the workpiece (1) using UG; S4. Machining the outline of workpiece (1): During the machining process of workpiece (1) by executing the CNC machining program, the tool holder of the machining machine tool contacts the outer contour of the tooling to realize the function of driving the tooling to rotate, ensuring that the outline of workpiece (1) is formed in one clamping. S5. After the workpiece (1) is processed, remove two screws (7) and check that the outline of the workpiece (1) is less than 0.02mm, which meets the design requirements.

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