Fixture for milling deep-cavity thin-wall part

Abstract

The clamp comprises a five-axis universal base matched with a machine tool workbench, a workpiece to be machined is clamped on the five-axis universal base, and a first side cavity, a second side cavity and a vertical cavity penetrating up and down are formed in the workpiece to be machined in a rough machining mode. A bottom plate is installed on the five-axis universal base, a workpiece to be machined is positioned on the bottom plate, a cover plate is fixed to the top of the workpiece to be machined, the cover plate is hollow and matched with the vertical cavity, a plurality of screw ejector blocks are embedded in the first side cavity, a pressing plate is arranged in the second side cavity, the pressing plate is connected with the bottom plate, and the bottom of the pressing plate abuts against the second side cavity. By additionally arranging the cover plate and the screw ejector block, the rigidity of the suspended thin-wall part on the workpiece to be machined is effectively improved, the requirements for improving the rotating speed and feeding of a cutter can be effectively met, and the surface smoothness of a machining inclined plane sealing surface is guaranteed.

Description

Technical Field

[0001] The utility model relates to the technical field of improved design of tooling fixtures for auxiliary machining, in particular to a fixture used for milling deep cavity thin-walled parts. Background Art

[0002] Currently, most of the tooling for processing thin-walled cavity workpieces is relatively simple. During operation, the workpiece must be pressed on the workbench with a simple pressing plate, and the position of the workpiece must be changed multiple times to complete one or several processes. In addition, multiple sets of tooling are required to process such parts, which increases the technical requirements for front-line operators and increases the secondary consumption cost of processing. On the other hand, the operator must re-align the part every time it is changed, and must pay attention to whether there is interference during the processing of such thin-walled parts, as well as deformation problems caused by different force clamping positions of the parts during processing, resulting in low processing efficiency.

[0003] Fixtures for machining deep-cavity, thin-walled parts typically use only a pressure plate without a cover plate or screw top block. The thin-walled areas of the first and second side cavities have low rigidity and a wall thickness of only 7.5mm. The tops of these thin-walled areas are completely suspended in the air, causing tool chatter when machining the inclined sealing surfaces of these side cavities with a T-cut. The surface finish and flatness during fine-flying of the cutter fail to meet the drawing requirements. Due to the tool chatter caused by the tool feed being at the weakest point of the thin-walled area, the machining process often results in overcutting by 1mm, resulting in a high product scrap rate. Furthermore, the tool feed speed is low, resulting in low machining efficiency and a rough sealing surface with unsatisfactory sealing effects.

[0004] Prior art patent publication CN215280992U discloses a fixture for machining thin-walled, hollow, and irregularly shaped parts. The fixture comprises a base, a vertical plate, several positioning assemblies, and several movable support assemblies mounted on the base. The vertical plate is secured to the base, and the positioning and movable support assemblies are movably connected to the base. The vertical plate is provided with several positioning pins and positioning bolts. This utility model improves the positioning and clamping methods of the existing fixture, providing technical support for high-precision machining of engine bracket parts.

[0005] Patent announcement number CN219212329U discloses a special fixture for multi-interference thin-walled cavity workpieces, comprising a base and a clamping workpiece assembly. The clamping workpiece assembly comprises a pressure rod, a fixed pin, a screw, a connecting column, a chassis, a threaded sleeve, a central shaft sleeve, a connecting pin, a central shaft, an inner joint, and an outer joint. The chassis is fixedly connected to the base, and the base is provided with a central shaft at its center. The top of the central shaft is threadedly connected to a threaded sleeve. Several connecting pins are provided in the middle of the central shaft. Each of the connecting pins is hingedly connected to an inner joint. Pressure rods are hingedly connected to each side of the base. The outer sides of the two pressure rods are each provided with a threaded hole, in which a screw is threadedly connected. The utility model makes clamping and tightening more convenient, and the clamping operation can be performed directly by tightening the bolts and sleeves. The force applied to the parts is more uniform, solving the problem of deformation caused by different force clamping positions during operation, thereby reducing deformation. Alignment is more convenient, reducing costs, and improving machine tool utilization.

[0006] The above technical solution cannot meet the clamping requirements of special deep-cavity thin-walled parts because their own rigidity is low, and the wall thickness is only 7.5mm. The bottom of the wall is completely suspended. When the T-knife is used to process the inclined sealing surface of the inner cavity, the tool will vibrate and the surface finish and flatness will not meet the processing requirements of the drawing.

[0007] In order to solve one of the above problems, the present application provides a fixture for milling deep cavity thin-walled parts. Utility Model Content

[0008] The purpose of the utility model is to solve the problems existing in the prior art, and to propose a fixture for milling deep-cavity thin-walled parts. By adding a cover plate and a screw top block, the rigidity of the suspended thin-walled part on the workpiece to be processed is effectively increased, which can effectively meet the requirements of increasing the tool speed and feed, and ensure the surface finish of the processed inclined sealing surface.

[0009] In order to achieve the above-mentioned purpose, the utility model adopts the following technical solutions: a fixture for milling deep-cavity thin-walled parts, comprising a five-axis universal base matched with a machine tool worktable, the machine tool is a conventional machine and will not be described in detail here, the five-axis universal base clamps the workpiece to be processed, and the workpiece to be processed is roughly processed to have a first side cavity, a second side cavity and a vertical cavity running through the top and bottom, a base plate is installed on the five-axis universal base, the workpiece to be processed is positioned on the base plate, and the workpiece to be processed is accurately positioned before clamping, a cover plate is fixed on the top of the workpiece to be processed, the cover plate is hollow and matches the vertical cavity, so as to increase the top structural strength of the workpiece to be processed and facilitate the milling of the vertical cavity, a plurality of screw top blocks are embedded in the first side cavity, the screw top blocks are used to assist in increasing the rigidity of the first side cavity and reduce its vibration and deformation during processing, a pressure plate is provided in the second side cavity, the pressure plate is connected to the base plate and the bottom of the pressure plate abuts against the second side cavity, so that the bottom structural strength of the workpiece to be processed is increased and the processing deformation is reduced.

[0010] Furthermore, the workpiece to be processed as described above is also roughly machined with a left cavity and a right cavity, and the left cavity and the right cavity respectively penetrate the top of the workpiece to be processed through vertical side holes, and the cover plate is fixed to the top of the workpiece to be processed by threaded connection through bolts passing through the vertical side holes.

[0011] Furthermore, the first side cavity as described above is close to the top of the workpiece to be processed, so that the top of the workpiece to be processed is a thin-walled portion, and the screw top block is located in the first side cavity and supports the upper and lower end surfaces of the first side cavity.

[0012] Furthermore, the screw top block as described above is composed of a bolt and a nut threadedly connected, and the components are simple and low-cost. In order to prevent the screw top block from directly contacting the completed fine-machined surface, buffer materials such as gaskets or silicone sheets can be placed on both ends of the screw top block.

[0013] Furthermore, the second side cavity as described above is close to the bottom of the workpiece to be processed, so that the bottom of the workpiece to be processed is a thin-walled portion, and the pressing plate is located in the second side cavity and pressed against the lower end surface of the second side cavity.

[0014] Furthermore, a rubber pad is provided between the pressing plate and the lower end surface of the second side cavity as described above. The rubber pad can prevent the pressing plate from directly contacting the completed fine-machined part, thereby playing a certain protective role.

[0015] Furthermore, the pressing plate as described above is fastened to the base plate by bolts so as to clamp and fix the workpiece to be processed on the base plate.

[0016] Furthermore, the workpiece to be processed as described above is provided with a positioning post, and the cover plate is provided with a positioning blind hole. The positioning post cooperates with the positioning blind hole to perform preliminary positioning on the cover plate.

[0017] Furthermore, as described above, a positioning through hole is machined on the side of the workpiece to be processed, and a positioning pin is provided on the bottom plate. The positioning pin cooperates with the positioning through hole to perform preliminary positioning of the workpiece to be processed when clamped on the bottom plate.

[0018] Furthermore, the base plate as described above is a boss structure, a hole is opened in the middle portion of the base plate and is connected and fixed to a five-axis universal base, so as to facilitate installation and use on a machine tool.

[0019] Compared with the prior art, the beneficial effects of the present invention are: by adding a cover plate and a screw top block, the device effectively increases the rigidity of the suspended thin-walled part of the workpiece to be processed, which can effectively meet the requirements of increasing the tool speed and feed, and ensure the surface finish of the processed inclined sealing surface. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a three-dimensional diagram of the utility model;

[0021] Figure 2 This is an explosion diagram of the utility model;

[0022] Figure 3 This is the main view of the utility model;

[0023] Figure 4 It is a top view of the utility model;

[0024] Figure 5 for Figure 4 Cross-sectional view along the AA direction.

[0025] In the figure: 1. Cover plate; 2. Workpiece to be processed; 20. Vertical cavity; 21. First side cavity; 22. Second side cavity; 23. Right side cavity; 24. Positioning column; 3. Screw top block; 4. Press plate; 5. Bottom plate; 51. Positioning pin; 6. Five-axis universal base. DETAILED DESCRIPTION

[0026] In the description of this utility model, it should be understood that the terms "upper," "lower," "front," "back," "left," "right," "top," "bottom," "inner," and "outer," etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings and are intended solely to facilitate the description of this utility model and simplify the description. They do not indicate or imply that the devices or components referred to must have a specific direction, be constructed, or operate in a specific direction. Therefore, they should not be construed as limitations on this utility model. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0027] In the description of the present utility model, it should be noted that, unless otherwise expressly specified and limited, the terms "fixed", "installed", "connected", "set", etc. should be understood in a broad sense. For example, when an element is referred to as being "fixed to" another element, it can be directly on the other element or there can be an intermediate element. When an element is considered to be "installed on" another element, it can be directly on the other element or there can be an intermediate element. When an element is considered to be "connected" to another element, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be a communication between the two elements.

[0028] For those skilled in the art, the specific meanings of the above terms in this utility model can be understood according to specific circumstances.

[0029] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0030] Example 1

[0031] Reference Figure 1-5 As shown, the present invention is a fixture for milling deep-cavity thin-walled parts, comprising a five-axis universal base 6 that cooperates with a machine tool worktable. The machine tool is a conventional milling machine and is not described in detail here. The five-axis universal base 6 clamps the workpiece 2 to be machined. The five-axis universal base 6 is a conventional component and is not described in detail here. The workpiece 2 to be machined is roughly machined with a first side cavity 21 and a second side cavity 22 and a vertical cavity 20 that passes through the upper and lower parts. Figure 3 and Figure 5 It can be seen that a base plate 5 is installed on the five-axis universal base 6, and a workpiece 2 to be processed is positioned on the base plate 5, which plays the role of preliminarily positioning the workpiece 2 to be processed. A cover plate 1 is fixed on the top of the workpiece 2 to increase the top structural strength of the workpiece 2 to be processed. The cover plate 1 is hollow and matches the vertical cavity 20. A plurality of screw top blocks 3 are embedded in the first side cavity 21. The screw top blocks 3 are used to assist in increasing the rigidity of the first side cavity 21 and reduce its vibration and deformation during machining. A pressure plate 4 is provided in the second side cavity 22. The pressure plate 4 is connected to the base plate 5 and the bottom of the pressure plate 4 is in contact with the second side cavity 22, so that the bottom structural strength of the workpiece 2 to be processed is increased and the deformation during milling is reduced.

[0032] During the machining process, the workpiece 2 to be machined on the device of the present invention is first clamped and fixed from different clamping directions using a pressing plate 4 and a vise to rough-machine the outer shape, inner cavity and deep cavity, with a single-side reserve of about 1 mm. The above clamping operation is then repeated for semi-finishing, followed by adding a cover plate 1 and a screw top block 3 to increase the structural strength and rigidity of the thin-walled portion of the side cavity, which is beneficial to improving the stability of the finishing operation and performing finishing operations on each side cavity.

[0033] Example 2

[0034] Reference Figure 1-5 As shown, based on the technical solution of embodiment 1, a fixture for milling deep-cavity thin-walled parts is provided. The workpiece 2 to be processed is also roughly machined with a left cavity and a right cavity 23. The left cavity and the right cavity 23 respectively penetrate the top of the workpiece 2 to be processed through vertical side holes. The cover plate 1 is fixed to the top of the workpiece 2 to be processed by threading bolts through the vertical side holes. Figure 1 and Figure 2 shown.

[0035] Furthermore, the first side cavity 21 is close to the top of the workpiece 2 to be processed, so that the top of the workpiece 2 to be processed is a thin-walled part. The screw top block 3 is located in the first side cavity 21 and supports the upper and lower end surfaces of the first side cavity 21. The number and position of the screw top blocks 3 are selected according to actual processing needs. Since the feed position is at the weakest position of the thin-walled part, the product may be scrapped if it is overcut by 1 mm due to the influence of the vibration generated by the feed. Adding the screw top block 3 can support the thin-walled part and increase its rigidity. Specifically, combined with Figure 2 and Figure 4 It can be seen that the screw top block 3 is composed of a bolt and a nut threaded connection, and the components are simple and low-cost. In order to prevent the screw top block 3 from directly contacting the completed finishing surface, buffer materials such as gaskets or silicone sheets can be placed on both ends of the screw top block 3.

[0036] Furthermore, the second side cavity 22 is close to the bottom of the workpiece 2 to be processed, so that the bottom of the workpiece 2 to be processed is a thin-walled part. The pressing plate 4 is located in the second side cavity 22 and pressed against the lower end surface of the second side cavity 22, which can increase the structural strength of the thin-walled part to avoid the vibration of the tool during milling. Figure 2 and Figure 4 As can be seen, a rubber pad is provided between the pressing plate 4 and the lower end surface of the second side cavity 22. The rubber pad can prevent the pressing plate 4 from directly contacting the finished part, thus playing a certain protective role. In addition, the pressing plate 4 is fastened to the base plate 5 by bolts to clamp and fix the workpiece 2 to the base plate 5.

[0037] Example 3

[0038] Reference Figure 1-5 As shown, based on the technical solution of embodiment 1, a fixture for milling deep cavity thin-walled parts is provided. Figure 2 As can be seen, the workpiece 2 is provided with positioning posts 24, and the cover plate 1 is provided with positioning blind holes. The positioning posts 24 cooperate with the positioning blind holes to provide preliminary positioning for the cover plate 1. Furthermore, positioning through holes are machined into the sides of the workpiece 2, and positioning pins 51 are provided on the base plate 5. These positioning pins 51 cooperate with the positioning through holes to provide preliminary positioning for the workpiece 2 when clamped on the base plate 5. Furthermore, the base plate 5 is a boss structure with a central opening for connection and fixation to a five-axis universal base 6, facilitating installation and use on the machine tool.

[0039] Before the improvement, the fixture structure for machining this deep-cavity, thin-walled part lacked a cover plate 1 and a screw top block 3. The thin-walled parts at the first side cavity 21 and the second side cavity 22 had low rigidity and a wall thickness of only 7.5 mm. The tops of the thin-walled parts were completely suspended in the air, and during machining, the T-cut tool would vibrate when machining the inclined sealing surfaces of the above-mentioned side cavities. The surface finish and flatness could not meet the drawing requirements during fine-flying. Due to the vibration caused by the tool feed at the weakest point of the thin-walled part, the machining process often resulted in overcutting by 1 mm, resulting in a high scrap efficiency. Furthermore, the tool feed speed was low, resulting in low machining efficiency, a rough sealing surface, and unsatisfactory sealing effects.

[0040] In response to the shortcomings of the above-mentioned fixture, improvements have been made. Based on the clamping operation of the above-mentioned fixture, the entire clamping process after the improvement is as follows: first lock the cover plate 1, process the vertical cavity 20, then add the screw top block 3 to support the first side cavity 21, perform the bevel sealing groove processing, and finally remove the cover plate 1 to fine-tune the surface flatness. The specific technical effects are as follows: adding the cover plate 1 and the screw top block 3 effectively increases the rigidity of the suspended thin-walled area of ​​the first side cavity 21, and the T-cut tool feed position can be changed from the middle to the two sides, increasing the rigidity of the feed position, which can effectively increase the tool speed and feed, and ensure the surface finish of the T-cut tool processed bevel sealing surface.

[0041] In the device of the present invention, the assembly and matching relationship of the various components involved, the five-axis universal base 6, gaskets and rubber pads, and bolts are existing technologies or materials. The relevant technical personnel can directly purchase or customize them from the market according to the required product models and specifications.

[0042] The electrical components mentioned in this article are all connected to an external main controller and 220V mains electricity or industrial electricity, and the main controller can be a conventional known device such as a computer that plays a control role.

[0043] The above description is only a preferred specific embodiment of the present invention. Common knowledge such as the specific structure and characteristics of the scheme is not described in detail here. For those skilled in the art, it is obvious that the present invention is not limited to the details of the above embodiment, and the present invention can be implemented in other specific forms without departing from the spirit or basic characteristics of the present invention. Therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive. Any person skilled in the art who is familiar with the technical field can make equivalent replacements or changes based on the technical solution and utility model concept of the present invention within the technical scope disclosed by the present invention, and they should be covered by the scope of protection of the present invention.

Claims

1. A fixture for milling deep-cavity thin-walled parts, comprising a five-axis universal base (6) matched with a machine tool worktable, the five-axis universal base (6) clamping a workpiece (2) to be machined, the workpiece (2) being roughly machined to have a first side cavity (21) and a second side cavity (22) and a vertical cavity (20) running through the workpiece (2), characterized in that: A base plate (5) is installed on the five-axis universal base (6), a workpiece (2) to be processed is positioned on the base plate (5), a cover plate (1) is fixed on the top of the workpiece (2), the cover plate (1) is hollow and matches the vertical cavity (20), a plurality of screw top blocks (3) are embedded in the first side cavity (21), a pressure plate (4) is provided in the second side cavity (22), the pressure plate (4) is connected to the base plate (5), and the bottom of the pressure plate (4) is in contact with the second side cavity (22).

2. A fixture for milling deep cavity thin-walled parts according to claim 1, characterized in that: The workpiece (2) to be processed is also roughly processed with a left cavity and a right cavity (23), and the left cavity and the right cavity (23) respectively penetrate the top of the workpiece (2) to be processed through vertical side holes, and the cover plate (1) is fixed to the top of the workpiece (2) to be processed by bolts passing through the vertical side holes and threaded connection.

3. The fixture for milling deep cavity thin-walled parts according to claim 1, characterized in that: The first side cavity (21) is close to the top of the workpiece (2) to be processed, and the screw top block (3) is located in the first side cavity (21) and supports the upper end surface and the lower end surface of the first side cavity (21).

4. A fixture for milling deep cavity thin-walled parts according to claim 3, characterized in that: The screw top block (3) is composed of a bolt and a nut threadedly connected.

5. The fixture for milling deep cavity thin-walled parts according to claim 1, characterized in that: The second side cavity (22) is close to the bottom of the workpiece (2) to be processed, and the pressing plate (4) is located in the second side cavity (22) and pressed against the lower end surface of the second side cavity (22).

6. A fixture for milling deep cavity thin-walled parts according to claim 5, characterized in that: A rubber pad is provided between the pressing plate (4) and the lower end surface of the second side cavity (22).

7. A fixture for milling deep cavity thin-walled parts according to claim 6, characterized in that: The pressing plate (4) is fastened to the base plate (5) by means of bolts.

8. The fixture for milling deep cavity thin-walled parts according to claim 1, characterized in that: The workpiece (2) to be processed is provided with a positioning column (24), and the cover plate (1) is provided with a positioning blind hole, and the positioning column (24) matches the positioning blind hole.

9. A fixture for milling deep cavity thin-walled parts according to claim 8, characterized in that: A positioning through hole is processed on the side of the workpiece (2) to be processed, and a positioning pin (51) is provided on the bottom plate (5), and the positioning pin (51) matches the positioning through hole.

10. A fixture for milling deep cavity thin-walled parts according to any one of claims 1 to 9, characterized in that: The bottom plate (5) is a boss structure, and a hole is opened in the middle of the bottom plate (5) and is connected and fixed to a five-axis universal base (6).

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