Accurate positioning device for workpiece machining

Abstract

The utility model belongs to the technical field of machining, and particularly relates to an accurate positioning device for workpiece machining. The precise positioning device for workpiece machining comprises a bottom plate; a positioning mechanism is arranged on at least one side surface of the bottom plate; the positioning mechanism comprises a first supporting seat and a second supporting seat which are oppositely arranged and used for supporting the two ends of a workpiece respectively, and the supporting faces of the supporting seats are X-direction positioning faces. A Y-direction positioning block is arranged on the first supporting seat; the Y-direction side pushing assembly is used for enabling one side face of the workpiece to abut against the Y-direction positioning face of the Y-direction positioning block; the grading positioning pin assembly is arranged between the first supporting base and the second supporting base and used for conducting primary positioning and secondary profiling positioning on the bottom face of the workpiece. And the first pressing assembly and the second pressing assembly are used for pressing the two ends of the workpiece on the first supporting seat and the second supporting seat respectively. According to the precise positioning device for workpiece machining, the precise positioning technology of multiple references, graded guiding and automatic centering is adopted, the positioning reference is matched with the product reference, defective products caused by machining positioning precision are eliminated, the machining yield is greatly improved, meanwhile, workpieces are easy to clamp, cost is low, efficiency is high, and the machining precision is high. The method has important technical and economic values.

Description

Technical Field

[0001] This utility model belongs to the field of machining technology, specifically relating to a precise positioning device for workpiece machining. Background Technology

[0002] Currently, based on the structural characteristics of typical workpieces, machining positioning devices typically select the workpiece's design 3D datum, adjust the dimensions to the median value according to datums such as A, B, and C, and simultaneously use conical pins and workpiece side positioning, cylinder clamping for precision cutting to meet the technical requirements of the workpiece drawing.

[0003] Production practice shows that the following problems usually exist during the machining of workpiece blanks:

[0004] 1. During the die casting process, uneven shrinkage in all directions is generally caused by specific structure and fluctuations in die casting process parameters. Heat treatment deformation and other factors lead to random dimensional deviations. Using a single side of the workpiece blank for positioning can easily result in dimensions exceeding the tolerance range after machining due to unreasonable tolerance allocation, which may even lead to scrap.

[0005] 2. Due to the parting surface of the mold, there are usually burrs and flash on the side of the blank. The flatness and dimensional accuracy after grinding are directly affected by the positioning of the side of the blank, which directly affects the machining accuracy of the workpiece.

[0006] 3. The side positioning of the positioning device uses a side-push cylinder for fixing, which is easily affected by air pressure fluctuations and cylinder parameters, thus affecting the positioning accuracy of the workpiece;

[0007] 4. If residual metal shavings on the workpiece bearing surface of the positioning device are not cleaned properly, it is also an important reason affecting the positioning accuracy and machining accuracy of the workpiece;

[0008] 5. The tapered pin on the positioning device only serves to position the workpiece in the thickness direction. Due to the large gap between the pin and the inner wall of the matching hole in other directions, the workpiece is prone to displacement during machining due to cutting force and vibration, which in turn affects the dimensional accuracy of the workpiece.

[0009] Given that the root cause of the above factors lies in the inadequacy of the workpiece positioning device, the inability to guarantee workpiece positioning accuracy, and fluctuations in machining dimensional accuracy, leading to dimensional instability, problems such as black skin, dimensions exceeding the required range, and even scrapping, seriously affecting product quality and causing significant economic losses, it is of great significance to optimize and improve the workpiece machining positioning device based on typical structural features. Utility Model Content

[0010] The purpose of this invention is to provide a precise positioning device for workpiece processing. It adopts multiple references, hierarchical guidance, and automatic centering precision positioning technology to solve the problems that existing workpiece processing positioning devices are prone to dimensional accuracy fluctuations during the machining of blanks, resulting in unstable dimensions, black skin, dimensions exceeding the required tolerance range, or even scrapping.

[0011] This utility model provides a precise positioning device for workpiece machining. The precise positioning device for workpiece machining includes:

[0012] A base plate; a positioning mechanism is provided on at least one side of the base plate;

[0013] The positioning mechanism includes:

[0014] The first and second support seats are arranged opposite to each other and are used to support the two ends of the workpiece, respectively, and the support surface of the support seats is the X-direction positioning surface; the first support seat is provided with a Y-direction positioning block.

[0015] The Y-axis side push assembly is used to press one side of the workpiece against the Y-axis positioning surface of the Y-axis positioning block;

[0016] A tiered positioning pin assembly, disposed between the first and second support seats, is used to position the bottom surface of the workpiece; and

[0017] The first pressing assembly and the second pressing assembly are used to press the two ends of the workpiece onto the first support and the second support, respectively.

[0018] In one embodiment of this utility model, the Y-axis lateral thrust assembly includes:

[0019] Side push block, with a rotating shaft installed in its middle;

[0020] The Y-axis lateral push driver has its moving end hinged to one end of the lateral push block;

[0021] The Y-axis side push driver is used to drive the side push block to rotate around the rotating shaft, so that the other end of the side push block can press one side of the workpiece against the Y-axis positioning surface of the Y-axis positioning block.

[0022] In one embodiment of this utility model, the rotating shaft is mounted on a second support base;

[0023] The Y-axis lateral push driver is located within the second support base.

[0024] In one embodiment of this utility model, a Z-axis driver is provided on the base plate;

[0025] The graded positioning pin assembly is fixed on the moving end of the Z-axis driver.

[0026] In one embodiment of this utility model, the graded positioning pin assembly includes a plurality of conical positioning pins and a plurality of contour positioning pins; the taper of the conical positioning pins and the contour positioning pins is 0.5° to 3°.

[0027] In one embodiment of this utility model, the fitting clearance between the conical locating pin and the workpiece is 0.3mm to 1.5mm, and the top surface height of the conical locating pin is 5mm to 10mm higher than that of the contour locating pin; the fitting clearance between the contour locating pin and the workpiece is 0.1mm to 0.3mm.

[0028] In one embodiment of this utility model, both the first pressing component and the second pressing component include:

[0029] The pressure driver is located on one side of the support base;

[0030] The pressure rod is hinged to the base plate in the middle, connected to the pressure driver at one end, and used to press down the end of the workpiece at the other end.

[0031] In one embodiment of this utility model, the base plate is further provided with several air blowing devices for blowing air onto the positioning surface to remove residual metal shavings on the positioning surface.

[0032] In one embodiment of this utility model, the air blowing device is mounted on a support base.

[0033] In one embodiment of this utility model, the upper end of the air blowing device is provided with a plurality of air blowing holes.

[0034] The beneficial effects of this utility model are:

[0035] Unlike existing technologies, this utility model provides a precise positioning device for workpiece processing. The device includes: a base plate; a positioning mechanism disposed on at least one side of the base plate; the positioning mechanism includes: a first support seat and a second support seat disposed opposite to each other, respectively used to support both ends of the workpiece, and the support surface of the support seat is an X-axis positioning surface; a Y-axis positioning block disposed on the first support seat; a Y-axis side-pushing assembly for pressing one side of the workpiece against the Y-axis positioning surface of the Y-axis positioning block; a graded positioning pin assembly disposed between the first and second support seats for contour positioning of the bottom surface of the workpiece; and a first pressing assembly and a second pressing assembly for pressing both ends of the workpiece onto the first and second support seats respectively. In other words, this utility model's precise positioning device for workpiece processing achieves precise positioning through multiple references, graded guidance, and automatic centering, ensuring that the positioning reference matches the product reference, eliminating defective products caused by machining positioning inaccuracies, and effectively improving the processing yield; simultaneously, the workpiece is easy to clamp, with low cost and high efficiency, possessing significant technical and economic value.

[0036] Other features and advantages of this invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objectives and other advantages of this invention are realized and obtained through the structures particularly pointed out in the description and the accompanying drawings.

[0037] To make the above-mentioned objectives, features and advantages of this utility model more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0038] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0039] Figure 1 This is a three-dimensional view of the workpiece machining precision positioning device of this utility model after the workpiece is assembled;

[0040] Figure 2 This is a perspective view of the workpiece machining precision positioning device of this utility model;

[0041] Figure 3 This is a partial side view of the workpiece machining precision positioning device of this utility model;

[0042] Figure 4 This is a partial cross-sectional view of the workpiece machining precision positioning device of this utility model;

[0043] Figure 5 This is a schematic diagram of the air blowing device of this utility model.

[0044] In the picture:

[0045] Base plate 100, positioning mechanism 200, workpiece 300, first support seat 1, X-direction positioning surface 101, Y-direction positioning block 102, Y-direction positioning surface 103, second support seat 2, Y-direction side push assembly 3, side push block 31, rotating shaft 32, Y-direction side push driver 33, graded positioning pin assembly 4, conical positioning pin 41, contour positioning pin 42, first pressing assembly 5, pressing driver 51, pressing rod 52, second pressing assembly 6, Z-direction driver 7, air blowing device 8, air blowing hole 81. Detailed Implementation

[0046] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0047] The selection of positioning datum for machined parts generally follows these principles: (1) Datum coincidence principle: Select the design datum as the positioning datum as much as possible to reduce errors caused by datum non-coincidence; (2) Unified datum (datum unchanged) principle: Select as many surfaces on the workpiece as possible using the same set of precision datums to ensure that the surfaces being machined have the correct relative positional relationship; (3) Mutual datum principle: When the positional accuracy requirement between two machined surfaces on the workpiece is relatively high, the two machined surfaces can be used as mutual datums for machining; (4) Self-datum principle: For some surface finishing processes, the machining allowance is required to be small and uniform, and the machining surface itself is often used as the precision datum for machining. This utility model, based on the typical structure of the workpiece, adopts a unified datum, selects multiple datum surfaces, and provides graded guidance to achieve precise positioning and ensure the accuracy requirements of key dimensions.

[0048] Traditional workpiece clamping techniques typically employ mechanical clamping, using threaded rods or pneumatic devices to hold the workpiece on a worktable. This method suffers from inconsistent workpiece force and difficulty in precise control. When using side positioning at one end, it's challenging to guarantee a reasonable distribution of critical dimension medians and dimensional tolerances, leading to dimensions exceeding tolerance requirements after machining and failing to meet the dimensional accuracy requirements of the drawings. Currently, while there are successful applications using probe-based centering to ensure critical dimension medians and tolerances, this approach is costly and economically unsustainable, hindering widespread adoption. Therefore, a solution that combines typical workpiece structural characteristics and machining dimensional accuracy requirements, selecting appropriate positioning datums, guiding methods, and positioning structures, can guarantee critical dimension medians and tolerances while offering advantages such as convenience and economy, facilitating widespread application and possessing significant technical and economic implications. The workpiece machining precision positioning device involved in this utility model adopts a precision positioning technology with multiple references and graded guidance. In particular, the guide pin and the positioning hole are set with a reasonable gap and a certain taper, which has an automatic centering function, realizes the matching of positioning reference with product reference, eliminates defective products caused by machining positioning accuracy, and can significantly improve the machining yield. At the same time, the workpiece is easy to clamp, with low cost and high efficiency, and has important technical and economic value.

[0049] Based on the aforementioned precise positioning device, a zero-defect product rate of 10,000 parts has been achieved in the high-precision CNC machining process of typical die-cast parts. Production practice has proven that it has high technical and economic value.

[0050] This utility model provides a precise positioning device for workpiece processing, which will be described in detail below. It should be noted that the order of description of the following embodiments is not intended to limit the preferred order of the embodiments of this utility model. Furthermore, in the following embodiments, the descriptions of each embodiment have their own emphasis; parts not described in detail in a certain embodiment can be referred to in the relevant descriptions of other embodiments.

[0051] See Figure 1 , Figure 2 and Figure 3 In one embodiment, a base plate 100 is provided; a positioning mechanism 200 is provided on at least one side of the base plate 100; the positioning mechanism 200 includes: a first support seat 1 and a second support seat 2 disposed opposite to each other, respectively used to support the two ends of the workpiece 300, and the support surface of the support seat is an X-direction positioning surface 101; a Y-direction positioning block 102 is provided on the first support seat 1; a Y-direction side push assembly 3 is used to press one side of the workpiece against the Y-direction positioning surface 103 of the Y-direction positioning block 102; a graded positioning pin assembly 4 is disposed between the first support seat 1 and the second support seat 2, used to position the bottom surface of the workpiece; and a first pressing assembly 5 and a second pressing assembly 6 are used to press the two ends of the workpiece onto the first support seat 1 and the second support seat 2 respectively.

[0052] In this embodiment, the first pressing component 5 and the second pressing component 6 press the two ends of the workpiece onto the first support base 1 and the second support base 2 respectively, which can position the workpiece 300 in the X direction; the side of the Y-direction positioning block 102 facing the workpiece 300 can be the Y-direction positioning surface 103, and the Y-direction side pushing component 3 can press one side of the workpiece against the Y-direction positioning surface 103 of the Y-direction positioning block 102, thereby positioning the workpiece 300 in the Y direction; the bottom surface of the workpiece 300 has some holes, and the graded positioning pin component 4 can make the draft angle according to the product shape, so that the positioning is firm and reliable.

[0053] Optionally, positioning mechanisms 200 may be provided on both opposite sides of the base plate 100.

[0054] In this embodiment, the graded positioning pin assembly 4 can achieve precise positioning of the bottom surface of the workpiece by using multiple references and graded guidance.

[0055] Specifically, the graded positioning pin assembly 4 includes several conical positioning pins 41 and several contour positioning pins 42; the taper of the conical positioning pins 41 and the contour positioning pins 42 is 0.5° to 3°. The taper of the conical positioning pins 41 and the contour positioning pins 42 can be consistent with the draft angle of the positioning hole of the workpiece blank, and has an automatic centering function.

[0056] Furthermore, the top surface height of the conical locating pin 41 can be higher than that of the contour locating pin 42. In this way, the conical locating pin 41 first serves as a positioning guide, and then the contour locating pin 42 can perform contour-following precise positioning of the hole, achieving graded guidance and precise positioning. Optionally, the top surface height of the conical locating pin 41 can be 5mm to 10mm higher than that of the contour locating pin 42.

[0057] Furthermore, the clearance between the conical locating pin 41 and the workpiece can be 0.3mm to 1.5mm, and the clearance between the contour locating pin 42 and the workpiece can be 0.1mm to 0.3mm.

[0058] See Figure 4 Optionally, the Y-axis side-push assembly 3 includes: a side-push block 31, in which a rotating shaft 32 is mounted; a Y-axis side-push driver 33, the moving end of which is hinged to one end of the side-push block 31; the Y-axis side-push driver 33 is used to drive the side-push block 31 to rotate around the rotating shaft 32, so as to drive the other end of the side-push block 31 to press one side of the workpiece against the Y-axis positioning surface 103 of the Y-axis positioning block 102.

[0059] Preferably, in order to save space occupied by the clamp, the rotating shaft 32 is mounted on the second support base 2; the Y-axis side push driver 33 is disposed inside the second support base 2.

[0060] See Figure 2 In this embodiment, a Z-axis driver 7 is provided on the base plate 100; the graded positioning pin assembly 4 is fixed on the moving end of the Z-axis driver 7. The Z-axis driver 7 can drive the graded positioning pin assembly 4 to move and position.

[0061] See Figure 2 As an optional implementation, both the first pressing component 5 and the second pressing component 6 include: a pressing driver 51, which is disposed on one side of the support base; and a pressing rod 52, the middle part of which is hinged to the base plate 100, one end of which is connected to the pressing driver 51, and the other end of which is used to press down the end of the workpiece 300.

[0062] See Figure 2 and Figure 5 Preferably, the base plate 100 is further provided with a plurality of air blowing devices 8 for blowing air onto the positioning surface to remove residual metal shavings.

[0063] For example, see Figure 5The air blowing device 8 can be provided with 4 units. The upper end of the air blowing device 8 is provided with 2 air blowing holes 81. The air blowing holes 81 can be aligned with the X-direction positioning surface 101, the Y-direction positioning surface 103, and the sides of the conical positioning pin 41 and the contour positioning pin 42, etc. (the thick lines in the figure indicate the orientation of the air blowing holes 81). It is used to blow away the metal chips remaining on each positioning surface 101 and prevent the metal chips from interfering with the positioning.

[0064] Optionally, the air blowing device 8 is mounted on a support base, and the interior of the first support base 1 and the second support base 2 may be provided with an air passage communicating with the air blowing device 8.

[0065] In summary, the workpiece machining precision positioning device of this utility model can blow air onto the positioning bearing surface before clamping to keep it clean and free from interference; the contour positioning pin can position and guide the contouring, making it easy to pick up and put down the product; the contour positioning pin is symmetrically distributed along the center line to fix the Y-axis limit; the positioning pin is fixed to meet the product's cutting rigidity requirements; the X-axis clamping fixes the X-axis limit; the product clamping and positioning method is simple, precise and practical, and the shape and position dimensions are effectively controlled; the rigidity of the positioning pin meets the product's repeated cutting performance, ensuring the consistency of machining dimensional accuracy of different batches of workpieces.

[0066] It should be noted that all components selected in this utility model (components whose specific structures are not described) are general standard parts or components known to those skilled in the art, and their structures and principles can be learned by those skilled in the art through technical manuals or conventional experimental methods.

[0067] In the description of the embodiments of this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0068] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0069] Based on the above-described preferred embodiments of this utility model, and through the foregoing description, those skilled in the art can make various changes and modifications without departing from the technical concept of this utility model. The technical scope of this utility model is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. A precise positioning device for workpiece machining, characterized in that, include: A base plate (100); a positioning mechanism (200) is provided on at least one side of the base plate (100); The positioning mechanism (200) includes: The first support base (1) and the second support base (2) are arranged opposite to each other and are used to support the two ends of the workpiece (300), and the support surface of the support base is the X-direction positioning surface (101); the first support base (1) is provided with a Y-direction positioning block (102); The Y-direction side push assembly (3) is used to press one side of the workpiece against the Y-direction positioning surface (103) of the Y-direction positioning block (102); A tiered positioning pin assembly (4) is disposed between the first support (1) and the second support (2) for positioning the bottom surface of the workpiece; and The first pressing assembly (5) and the second pressing assembly (6) are used to press the two ends of the workpiece onto the first support (1) and the second support (2) respectively.

2. The workpiece machining precision positioning device according to claim 1, characterized in that, The Y-axis lateral thrust assembly (3) includes: Side push block (31), with a rotating shaft (32) installed in its middle; Y-axis side push driver (33), the moving end of which is hinged to one end of side push block (31); The Y-axis side push driver (33) is used to drive the side push block (31) to rotate around the rotating shaft (32), so that the other end of the side push block (31) will press one side of the workpiece against the Y-axis positioning surface (103) of the Y-axis positioning block (102).

3. The workpiece machining precision positioning device according to claim 2, characterized in that, The rotating shaft (32) is mounted on the second support base (2); The Y-axis lateral push drive (33) is disposed within the second support base (2).

4. The workpiece machining precision positioning device according to claim 1, characterized in that, A Z-axis driver (7) is provided on the base plate (100); The graded positioning pin assembly (4) is fixed on the moving end of the Z-axis driver (7).

5. The workpiece machining precision positioning device according to claim 1, characterized in that, The graded positioning pin assembly (4) includes a plurality of conical positioning pins (41) and a plurality of contour positioning pins (42); The taper of the conical locating pin (41) and the contour locating pin (42) is 0.5° to 3°.

6. The workpiece machining precision positioning device according to claim 5, characterized in that, The clearance between the conical locating pin (41) and the workpiece is 0.3mm to 1.5mm, and the top surface height of the conical locating pin (41) is 5mm to 10mm higher than that of the contour locating pin (42). The clearance between the contour positioning pin (42) and the workpiece is 0.1mm to 0.3mm.

7. The workpiece machining precision positioning device according to claim 1, characterized in that, Both the first pressing component (5) and the second pressing component (6) include: A pressure drive (51) is located on one side of the support base; The pressure rod (52) is hinged to the base plate (100) at one end, connected to the pressure driver (51) at the other end, and used to press down the end of the workpiece.

8. The workpiece machining precision positioning device according to claim 1, characterized in that, The base plate (100) is also provided with several air blowing devices (8) for blowing air onto the positioning surface to remove residual metal shavings on the positioning surface.

9. The workpiece machining precision positioning device according to claim 8, characterized in that, The air blowing device (8) is mounted on the support.

10. The workpiece machining precision positioning device according to claim 9, characterized in that, The upper end of the air blowing device (8) is provided with a plurality of air blowing holes (81).

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