High-precision clamp

Abstract

The utility model relates to the technical field of clamps, and particularly discloses a high-precision clamp which can reduce stress and damage on the surface of a part during clamping, is favorable for controlling the mass production quality of products and can improve the clamping and machining efficiency of the part, and comprises a base fixed on a numerical control machine tool and a clamp body fixed on the top of the base, a negative pressure cavity is formed in the clamp body, an access port communicated with the negative pressure cavity and an external air pressure device is formed in one side face of the clamp body, a clamping work molded surface is formed on the top face of the clamp body, and at least one supporting ring is arranged in the clamping work molded surface. A negative pressure vent hole which penetrates through the clamping working molded surface and is communicated with the negative pressure cavity is formed in the space in the supporting ring, the outer ring face of the supporting ring is sleeved with a sealing ring, a plurality of supporting columns and a plurality of positioning columns are arranged on the side of the supporting ring, the positioning columns are used for being connected with holes in a part to be clamped in an inserted mode, and the supporting ring and the supporting columns jointly support a product.

Description

Technical Field

[0001] The utility model relates to the technical field of clamps, in particular to a high-precision clamp. Background Art

[0002] When processing high-precision, high-appearance precision plate parts with low material hardness, it is often necessary to clamp the parts with a fixture to achieve the positioning of the parts. At present, the industry mainly uses vises and pneumatic clamps to position parts. Due to the large clamping force of vises and pneumatic clamps, significant shear force will inevitably be generated, resulting in deformation of parts, surface crushing, and residual stress accumulation, which will affect the appearance of the product and is not conducive to controlling the quality of the product during mass production. In addition, when clamping with vises and pneumatic clamps, the position of the parts needs to be repeatedly adjusted to ensure the clamping alignment, and the efficiency of part clamping is low, which in turn affects the processing efficiency of the product. Utility Model Content

[0003] Based on this, it is necessary to provide a high-precision fixture that can reduce the force and damage on the surface of parts during clamping, help control the quality of mass production of products, and improve the efficiency of part clamping and processing in order to address the above-mentioned shortcomings.

[0004] A high-precision clamp comprises a base for fixing on a CNC machine tool and a clamp body fixed on the top of the base, a negative pressure chamber is provided in the clamp body, an access port connected to the negative pressure chamber and an external air pressure device is provided on one side of the clamp body, a clamping working surface is formed on the top surface of the clamp body, at least one support ring is provided in the clamping working surface, a negative pressure vent hole penetrating the clamping working surface and connected to the negative pressure chamber is provided in the inner space of the support ring, a sealing ring is provided on the outer ring surface of the support ring, a plurality of support columns and a plurality of positioning columns for plugging into holes on the parts to be clamped are provided on the sides of the support ring, the top surface of the support ring is flush with the top surface of the support column, and the support ring and the support column jointly support the product.

[0005] In one of the embodiments, a plurality of the support rings are arranged side by side on the clamping working surface to form a negative pressure adsorption area, and a row of the support columns are evenly arranged on both sides of the negative pressure adsorption area.

[0006] In one of the embodiments, four positioning columns distributed in a rectangular shape are arranged on the clamping working surface, and a supporting column is respectively arranged on both sides of each positioning column.

[0007] In one embodiment, an annular fixing groove is formed on the outer ring surface of the support ring adjacent to the top surface of the support ring, and the cross-section of the annular fixing groove is an arc-shaped structure. The sealing ring is nested in the annular fixing groove, and the sealing ring embedded in the annular fixing groove protrudes from the top surface of the support ring.

[0008] In one of the embodiments, the height difference between the top of the sealing ring embedded in the annular fixing groove and the top surface of the supporting ring is 0.08-0.12 mm.

[0009] In one of the embodiments, the inner space of the support ring forms a negative pressure cavity, and the depth of the negative pressure cavity is smaller than the height of the support ring.

[0010] In one of the embodiments, a trachea interface is installed at the access port, and the trachea interface is connected to an external air pressure device through a negative pressure air pipe.

[0011] In one embodiment, the base includes a pedestal and a support platform fixed on the top of the pedestal, the length of the support platform is greater than the length of the pedestal, the width of the support platform is equal to the width of the pedestal, and the clamp body is fixed on the support platform.

[0012] In one of the embodiments, at least one first mounting hole for bolt connection with a CNC machine tool is provided on the base, a plurality of second mounting holes are provided on the support platform, each second mounting hole passes through the top surface and the bottom surface of the support platform, and a plurality of mounting grooves corresponding to the second mounting holes are provided on the bottom surface of the clamp body, and the base is fixedly connected to the clamp body by a plurality of bolts that pass through the second mounting holes and are inserted into the mounting grooves in a one-to-one manner.

[0013] In one of the embodiments, a plurality of weight-reducing holes are respectively provided on the base and the supporting platform.

[0014] By implementing the high-precision clamp of the utility model, positioning columns are designed on the clamping working surface of the clamp, which can realize rapid alignment and clamping of parts and improve the clamping and processing efficiency of parts; by providing support rings and support columns, the contact area between the clamp and the surface of the part is reduced, and the extrusion force on the part during clamping is reduced, which can avoid part deformation and appearance compression defects caused by clamping, thereby effectively preventing debris from potentially affecting the positioning accuracy, which is beneficial to controlling the quality of products during mass production. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a schematic structural diagram of a high-precision fixture in one embodiment of the utility model;

[0016] Figure 2 This is a schematic diagram of the structure of a high-precision fixture after clamping a part in one embodiment of the utility model;

[0017] Figure 3 This is a schematic structural diagram of a base in one embodiment of the utility model;

[0018] Figure 4 It is a structural schematic diagram of a clamp body from one perspective in an embodiment of the utility model;

[0019] Figure 5 It is a structural schematic diagram of another viewing angle of a clamp body in one embodiment of the utility model;

[0020] Figure 6 The figure is a schematic cross-sectional structure diagram of a specific embodiment of the present invention. DETAILED DESCRIPTION

[0021] In order to make the above-mentioned purposes, features and advantages of the utility model more obvious and easy to understand, the specific implementation methods of the utility model are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the utility model. However, the utility model can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the utility model, so the utility model is not limited by the specific embodiments disclosed below.

[0022] The utility model aims to achieve high-precision clamping and positioning for plate-like parts made of low-hardness materials and with high requirements on appearance. The clamping repeat positioning accuracy needs to be controlled within 0.01mm to ensure processing accuracy. At the same time, special consideration is given to reducing the force during the clamping process during the design process to avoid deformation of parts and appearance defects caused by clamping. In response to this problem, the utility model proposes a high-precision fixture that can reduce the force and damage on the surface of parts during clamping, is conducive to controlling the mass production quality of products, and can improve the clamping and processing efficiency of parts. Its refined structure, high repeat positioning accuracy and uniform negative pressure distribution jointly ensure its excellent high-precision clamping and sealing performance. At the same time, its operation is intuitive and simple, and the contact area between the fixture and the processed parts is minimized to reduce damage to the surface of the parts.

[0023] For details, please combine Figure 1 , Figure 2 as well as Figure 6The high-precision fixture 10 of this embodiment includes a base 100 for fixing on a CNC machine tool and a clamp body 200 fixed on the top of the base 100. The clamp body 200 is used to provide a clamping portion for the part 20. A negative pressure chamber 210 is provided in the clamp body 200. An access port 220 connected to the negative pressure chamber 210 and an external air pressure device is provided on one side of the clamp body 200. The access port 220 is used to introduce external negative pressure into the negative pressure chamber 210 so as to provide an adsorption force for the part 20 to be adsorbed on the surface of the clamp body 200. The top surface of the clamp body 200 forms a clamping working surface, and at least one support ring 230 is arranged in the clamping working surface. The inner space of the support ring 230 is provided with a negative pressure vent 240 that penetrates the clamping working surface and communicates with the negative pressure chamber 210. The outer ring surface of the support ring 230 is sleeved with a sealing ring 250, and the inner space of the support ring 230 forms a negative pressure cavity 231. The negative pressure cavity 231 is used to increase the negative pressure contact area between the part 20 and the clamp body 200, so that the part 20 is tightly attached to the clamp body 200; the sealing ring 250 is used to ensure the stability of the air pressure in the negative pressure cavity 231, avoid the problem of the part 20 falling off the clamp body 200 due to air leakage in the negative pressure cavity 231, and improve the stability of the clamping of the part 20. A plurality of support columns 260 and a plurality of positioning columns 270 for plugging into holes on the part 20 to be clamped are arranged on the side of the support ring 230. The top surface of the support ring 230 is flush with the top surface of the support column 260, and the support ring 230 and the support column 260 jointly support the product. The combination of the support ring 230 and the support column 260 reduces the contact area between the part 20 and the clamp body 200 while ensuring that the negative pressure can be stably transmitted to the surface of the part 20 and the part 20 is adsorbed on the clamp body 200. In addition, by providing the support ring 230 and the support column 260, the distance between the part 20 and the top surface of the clamp body 200 is extended, so that there is a large avoidance space between the bottom surface of the part 20 and the clamping working surface, which can effectively avoid the surface of the part 20 from being crushed or bruised.

[0024] The above-mentioned high-precision clamp 10 is designed with a positioning column 270 on the clamping working surface of the clamp, which can realize the rapid positioning clamping of the part 20 and improve the clamping and processing efficiency of the part 20; by setting the support ring 230 and the support column 260, the contact area between the clamp and the surface of the part 20 is reduced, and the extrusion force on the part 20 during the clamping process is reduced, which can avoid the deformation of the part 20 and the appearance of the crushing defects caused by clamping. At the same time, the support ring 230 and the support column 260 are set in a raised structure, so that the operator can use tools such as air guns to efficiently and quickly remove the debris scattered on the clamping working surface during the processing and clamping process, thereby effectively preventing the debris from potentially affecting the positioning accuracy, which is beneficial to controlling the quality of the product during mass production and ensuring the processing stability and quality of the part 20, which is of great significance for improving processing efficiency and optimizing the production process.

[0025] The base 100 is used to support and install the clamp body 200, so as to fix the clamp body 200 and the parts on the CNC machine tool. Figure 1 as well as Figure 3-6 The base 100 includes a base 110 and a support platform 120 fixed on the top of the base 110. The length of the support platform 120 is greater than the length of the base 110, and the width of the support platform 120 is equal to the width of the base 110. The clamp body 200 is fixed on the support platform 120. Furthermore, the thickness of the support platform 120 is less than the thickness of the base 110. In this embodiment, the support platform 120 and the base 110 are integrally formed, and a plurality of weight-reducing holes 130 are respectively provided on the base 110 and the support platform 120. By providing the weight-reducing holes 130 on the base 110 and the support platform 120, the overall weight of the base 100 and the amount of material used in the processing of the base 100 can be reduced. In one embodiment, at least one first mounting hole 140 for bolt connection with a CNC machine tool is provided on the base 110, and a plurality of second mounting holes 150 are provided on the support platform 120, each of which penetrates the top and bottom surfaces of the support platform 120, and a plurality of mounting grooves 280 corresponding to each second mounting hole 150 are provided on the bottom surface of the clamp body 200, and the base 100 is fixedly connected to the clamp body 200 by a plurality of bolts passing through the second mounting holes 150 and inserted into the mounting grooves 280 in a one-to-one correspondence. In this embodiment, the first mounting hole 140 and the second mounting hole 150 are both threaded holes, and the mounting grooves 280 are threaded grooves. Preferably, two first mounting holes 140 are spaced apart at the bottom of the base 110, the support platform 120 is a rectangular plate-like structure, a second mounting hole 150 is respectively provided at the four corners of the support platform 120, the bottom surface of the clamp body 200 is a rectangular plane, a mounting groove 280 is respectively provided at the four corners of the bottom surface of the clamp body 200, the base 110 is fixed to the CNC machine tool by a No. 1 bolt 160 passing through the first mounting hole 140, and the support platform 120 is fixed to the clamp body 200 by a No. 2 bolt 170 passing through the second mounting hole 150 and inserted into the corresponding mounting groove 280.

[0026] In this embodiment, the clamp body 200 is made of aluminum or 45# stainless steel to extend the service life of the clamp body 200. Figure 1 as well as Figure 4-6In this embodiment, in order to increase the adsorption force of the clamp body 200 on the part, a plurality of support rings 230 are arranged side by side on the clamping working surface to form a negative pressure adsorption area, and a row of support columns 260 are evenly arranged on both sides of the negative pressure adsorption area. Preferably, three support rings 230 are evenly arranged on the clamping working surface along the length direction of the clamp body 200. In addition, in this embodiment, when a plurality of support rings 230 are arranged on the clamping working surface, the diameters of the support rings 230 can be the same or different; when the clamping working surface contains two or more support rings 230 of different diameters, the arrangement of the support rings 230 on the clamping working surface needs to meet the requirement that the negative pressure adsorption force on the bottom of the part is uniform, so as to ensure the stability of the part clamping. Furthermore, four positioning columns 270 distributed in a rectangular shape are arranged on the clamping working surface, and a support column 260 is arranged on both sides of each positioning column 270. A convex portion is provided on the top of the positioning column 270 for embedding into the corresponding hole on the part. The outer contour shape of the convex portion is adapted to the inner contour shape of the corresponding hole on the part, and the precision tolerance of the convex portion is within ±0.0025mm. It is mainly used for high-precision matching with the clamping positioning hole of the part to ensure the repeated installation positioning accuracy of the part.

[0027] In addition, in this embodiment, the support ring 230 and the support column 260 are the vertical downward positioning references of the parts during the clamping process. The contact area with the parts is small, which can effectively reduce the appearance defects caused by crushing. By evenly arranging the support columns 260 on the clamping working surface, the parts can be uniformly and stably subjected to force during clamping. In order to improve the positioning accuracy of the support columns 260 and the support ring 230 on the parts, when the parts are adsorbed on the surface of the clamp body 200, the distance between the bottom surface of the parts and the top surfaces of the support columns 260 and the support ring 230 is within 0.003mm, that is, the vertical positioning accuracy of the clamp body 200 of this embodiment is within 0.003mm.

[0028] In one embodiment, the outer ring surface of the support ring 230 is provided with an annular fixing groove 232 adjacent to the top surface of the support ring 230. The annular fixing groove 232 is used to define the position of the sealing ring 250. The cross section of the annular fixing groove 232 is an arc-shaped structure. The sealing ring 250 is nested in the annular fixing groove 232, and the sealing ring 250 embedded in the annular fixing groove 232 protrudes from the top surface of the support ring 230. The inner surface of the annular fixing groove 232 and the outer surface of the sealing ring 250 fit and restrain each other, so that the sealing ring 250 can be prevented from falling off from the annular fixing groove 232 to ensure the reliability of the seal. Further, the height difference between the top of the sealing ring 250 embedded in the annular fixing groove 232 and the top surface of the support ring 230 is 0.08-0.12mm. Preferably, the height difference between the top of the sealing ring 250 embedded in the annular fixing groove 232 and the top surface of the support ring 230 is 0.1 mm. In this way, when the part is adsorbed on the clamp body 200, the bottom surface of the part presses the sealing ring 250 under the action of negative pressure and fits with the top of the support ring 230. In this process, the sealing ring 250 is deformed and blocks the gap between it and the bottom surface of the part, which can effectively prevent the negative pressure cavity 231 from leaking during operation.

[0029] In one embodiment, the depth of the negative pressure cavity 231 is smaller than the height of the support ring 230, and the inner surface of the support ring 230 and the area on the clamping working surface located in the space inside the support ring 230 are provided with an anti-stick coating or an anti-stick surface. The anti-stick coating or the anti-stick surface surrounds the negative pressure cavity 231 to prevent the debris generated by the processing of the parts from sticking to the inner surface of the negative pressure cavity 231 when the parts are removed, thereby causing the problem of difficulty in cleaning the clamp body 200.

[0030] In one embodiment, a trachea interface 290 is installed at the access port 220, and the trachea interface 290 is connected to the external air pressure device through a negative pressure air pipe 291, and the trachea interface 290 is threadedly connected to the access port 220. In addition, in this embodiment, the negative pressure chamber 210 is a strip-shaped channel extending along the length direction of the clamp body 200, and the cross section of the strip-shaped channel is a circular structure. The cross section of the access port 220 is also a circular structure, which reduces the difficulty of machining the clamp body 200 and the difficulty of assembling the trachea interface 290. The upper part of the strip-shaped channel is connected to the negative pressure vent hole 240.

[0031] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0032] The above-mentioned embodiments only express several implementation methods of the utility model, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the utility model patent. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the utility model, which all belong to the protection scope of the utility model. Therefore, the protection scope of the utility model patent shall be based on the attached claims.

Claims

1. A high-precision fixture, characterized in that: It includes a base for fixing on a CNC machine tool and a clamping body fixed on the top of the base, a negative pressure chamber is opened in the clamping body, an access port connected to the negative pressure chamber and an external air pressure device is opened on one side of the clamping body, the top surface of the clamping body forms a clamping working surface, at least one support ring is arranged in the clamping working surface, a negative pressure vent hole penetrating the clamping working surface and connected to the negative pressure chamber is arranged in the inner space of the support ring, a sealing ring is arranged on the outer ring surface of the support ring, a plurality of support columns and a plurality of positioning columns for plugging into holes on the parts to be clamped are arranged on the side of the support ring, the top surface of the support ring is flush with the top surface of the support column, and the support ring and the support column jointly support the product.

2. The high-precision fixture according to claim 1, characterized in that: A plurality of the support rings are arranged side by side on the clamping working surface to form a negative pressure adsorption area, and a row of the support columns are evenly arranged on both sides of the negative pressure adsorption area.

3. The high-precision fixture according to claim 1, characterized in that: The clamping working surface is provided with four positioning columns distributed in a rectangular shape, and each positioning column is provided with a supporting column on both sides thereof.

4. The high-precision fixture according to claim 1, characterized in that: The outer ring surface of the support ring is provided with an annular fixing groove adjacent to the top surface of the support ring. The cross section of the annular fixing groove is an arc-shaped structure. The sealing ring is nested in the annular fixing groove, and the sealing ring embedded in the annular fixing groove protrudes from the top surface of the support ring.

5. The high-precision fixture according to claim 4, characterized in that: The height difference between the top of the sealing ring embedded in the annular fixing groove and the top surface of the supporting ring is 0.08-0.12mm.

6. The high-precision fixture according to claim 1, characterized in that: The inner space of the support ring forms a negative pressure cavity, and the depth of the negative pressure cavity is smaller than the height of the support ring.

7. The high-precision fixture according to claim 1, characterized in that: A trachea interface is installed at the access port, and the trachea interface is connected to an external air pressure device through a negative pressure air pipe.

8. The high-precision fixture according to claim 1, characterized in that: The base comprises a pedestal and a support platform fixed on the top of the pedestal, the length of the support platform is greater than the length of the pedestal, the width of the support platform is equal to the width of the pedestal, and the clamp body is fixed on the support platform.

9. The high-precision fixture according to claim 8, characterized in that: The base is provided with at least one first mounting hole for bolt connection with a CNC machine tool, and the support platform is provided with multiple second mounting holes, each of which passes through the top and bottom surfaces of the support platform, and the bottom surface of the clamp body is provided with multiple mounting grooves corresponding to the second mounting holes one by one, and the base is fixedly connected to the clamp body by multiple bolts that pass through the second mounting holes and are inserted into the mounting grooves one by one.

10. The high-precision fixture according to claim 8, characterized in that: The base and the supporting platform are respectively provided with a plurality of weight-reducing holes.

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