CNC milling machine planar processing adaptive flexible floating clamp

Abstract

The utility model relates to CNC milling machine clamping fixture technical field, and disclose a kind of CNC milling machine plane processing self-adapting flexible floating clamp, including jig base, jig carrier plate, the isohypse support column for supporting jig carrier plate for being fixed on jig base, the lateral positioning block for workpiece side surface positioning being set on jig carrier plate, the Z direction positioning support block for constituting workpiece Z direction datum plane being set on jig carrier plate, the pressure jaw mechanism for pressing workpiece, and the side push clamping mechanism for clamping workpiece from lateral, still include at least one flexible floating support mechanism;The bottom of flexible floating support mechanism is fixed on jig base, its top is equipped with the support end that can float and can lock, support end penetrates jig carrier plate and protrudes on its upper surface;The utility model passes through the flexible support mechanism that middle part can float, can lock, automatically adapts the flatness error of workpiece, guarantees the quality stability and consistency of batch processing.

Description

Technical Field

[0001] This utility model relates to the field of CNC milling machine machining fixture technology, specifically an adaptive flexible floating fixture for CNC milling machine planar machining. Background Technology

[0002] CNC milling machine fixtures are core auxiliary equipment for achieving precision machining on CNC milling machines, and their development is closely related to the advancement of CNC machining technology. In the 1960s and 70s, when CNC milling machines were first applied, machining fixtures were mostly rigid, fixed structures that could only achieve simple positioning and clamping, resulting in poor adaptability. Each time a new product was needed, a new fixture had to be designed and manufactured, leading to low production efficiency. In the 1980s and 90s, with the rise of modular design concepts, modular fixtures became more common, enabling multi-product adaptation through the splicing of standardized modules. However, they still lacked the ability to adaptively adjust to differences in incoming materials.

[0003] Since the beginning of the 21st century, industries such as electronics and automobiles have continuously increased their requirements for the precision of component processing, especially for flat parts (such as mobile phone casings and computer panels), which have stringent requirements for flatness and uniformity of material thickness after processing. Traditional fixtures, due to their rigid support and clamping structures, cannot handle flatness errors in incoming materials (typically 0.1-0.5mm), leading to problems such as locally excessively thin or scrapped products after processing. To address this pain point, some fixtures have begun to incorporate simple elastic elements, but these can only achieve small-scale buffering and cannot actively correct flatness, still failing to meet the demands of high-precision processing. Against this backdrop, flexible floating fixtures with adaptive flatness correction functions have become a key focus of industry research and development, effectively compensating for the shortcomings of traditional fixtures and improving processing yield and efficiency. Utility Model Content

[0004] To address the shortcomings of existing technologies, this utility model provides an adaptive flexible floating fixture for CNC milling machine planar machining. It has the advantages of correcting product flatness, stable clamping, and high reference accuracy. It solves the problems of existing rigid fixtures being unable to cope with uneven material thickness caused by differences in incoming material flatness, uneven clamping force distribution causing product displacement, and easy wear of the reference requiring frequent maintenance.

[0005] To achieve the aforementioned goals of automatically correcting product flatness, clamping stability, and high reference accuracy, this utility model provides the following technical solution: A CNC milling machine planar machining adaptive flexible floating fixture, comprising a fixture base, a fixture carrier plate, multiple equal-height support columns fixed on the fixture base for supporting the fixture carrier plate, multiple lateral positioning blocks disposed on the fixture carrier plate for workpiece side positioning, multiple Z-axis positioning support blocks disposed on the fixture carrier plate for forming the Z-axis reference plane of the workpiece, multiple clamping jaw mechanisms for clamping the workpiece, and multiple side-pushing clamping mechanisms for clamping the workpiece from the side, and further comprising at least one flexible floating support mechanism; the bottom of the flexible floating support mechanism is fixed on the fixture base, and its top is provided with a floating and lockable support end, which penetrates the fixture carrier plate and protrudes from its upper surface.

[0006] Preferably, the flexible floating support mechanism is located in the central region of the fixture carrier plate.

[0007] Preferably, the top of the flexible floating support mechanism has a cross-shaped channel that extends along the central axis of the top of the flexible floating support mechanism, and its two channel arms are respectively arranged along the length and width directions of the support end, dividing the support end into four structurally symmetrical and independently load-bearing support areas.

[0008] Preferably, the top surface of the support end of the flexible floating support mechanism is higher than the upper surface of the Z-axis positioning support block in the initial state.

[0009] Preferably, the side-push clamping mechanism includes a cylinder support block, a second cylinder, and a clamping block; the cylinder support block is fixed to the lower end of the fixture base; the tail of the second cylinder is hinged to the cylinder support block; one end of the clamping block is hinged to the front end of the piston rod of the second cylinder.

[0010] Preferably, the plurality of side-push clamping mechanisms are mounted on the fixture carrier plate, and the movement direction of their clamping ends is parallel to the plane of the fixture carrier plate, for clamping the workpiece from the X and Y directions.

[0011] Preferably, the plurality of Z-axis positioning support blocks are distributed in the corner areas of the workpiece.

[0012] Preferably, the pressure claw mechanism includes a first cylinder and a pressure claw, the pressure claw being rotatably connected to the fixture base, and one end of the pressure claw being hinged to the front end of the piston rod of the first cylinder.

[0013] Preferably, there are six equal-height support columns, which are evenly fixed at the edge of the fixture base.

[0014] Preferably, the fixture carrier plate is fixedly installed on the top of the plurality of equal-height support columns by fasteners.

[0015] Compared with the prior art, this utility model provides an adaptive flexible floating fixture for CNC milling machine planar machining, which has the following beneficial effects: 1. This CNC milling machine's adaptive flexible floating fixture for planar machining automatically adapts to the flatness error of the incoming workpiece through a flexible support mechanism that can float and lock in the middle. During clamping, it corrects the workpiece to a state of complete contact with the Z-axis reference surface of the fixture without stress, fundamentally eliminating machining deformation caused by clamping stress. It significantly reduces the defect rate of products caused by uneven material thickness and overcutting due to the flatness problem of the incoming material, ensuring the quality stability and consistency of batch processing.

[0016] 2. This CNC milling machine features an adaptive flexible floating fixture for planar machining. During machining, the flexible support mechanism is locked, forming a stable rigid support system together with the surrounding equal-height support columns and Z-axis positioning blocks. This ensures overall rigidity during machining and prevents tool vibration. The entire clamping process can be controlled by a PLC program, with sequential actions, reducing manual intervention, improving production efficiency, and reducing reliance on operator skills. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the overall structure of this utility model; Figure 2 This is a schematic diagram of the overall structure for placing the workpiece according to this utility model; Figure 3 This is a schematic diagram of the flexible floating support mechanism of this utility model.

[0018] In the diagram: 1. Fixture base; 2. Equal-height support column; 3. Fixture carrier plate; 4. Flexible floating support mechanism; 41. Support end; 42. Cross-shaped channel; 43. Support area; 5. Second cylinder; 51. First cylinder; 6. Cylinder support block; 7. Claw mechanism; 71. Claw; 8. Lateral positioning block; 9. Z-axis positioning support block; 10. Lateral push clamping mechanism; 11. Clamping block; 12. Workpiece. Detailed Implementation

[0019] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0020] like Figure 1As shown, a CNC milling machine planar machining adaptive flexible floating fixture includes a fixture base 1, a fixture carrier plate 3, nine equal-height support columns 2 fixed on the fixture base 1 for supporting the fixture carrier plate 3, four lateral positioning blocks 8 disposed on the fixture carrier plate 3 for side positioning of workpiece 12, twelve Z-direction positioning support blocks 9 disposed on the fixture carrier plate 3 for forming the Z-direction reference plane of workpiece 12, four clamping jaw mechanisms 7 for clamping workpiece 12, and three side-pushing clamping mechanisms 10 for clamping workpiece 12 from the side, and also includes at least one flexible floating support mechanism 4; the bottom of the flexible floating support mechanism 4 is fixed on the fixture base 1, and its top... The workpiece 12 is provided with a floating and lockable support end 41, which penetrates the fixture carrier plate 3 and protrudes from its upper surface. The support end 41 of the flexible floating support mechanism 4 can float and adjust with the surface shape of the workpiece 12 without the need for pre-customized special support blocks. Combined with the Z-direction positioning support block 9 and the lateral positioning block 8 on the fixture carrier plate 3, the flexible floating support mechanism 4 can supplement the "three-point positioning" reference of the workpiece 12, which is especially suitable for situations where the bottom of the workpiece 12 is not flat or has local depressions, ensuring the accuracy of the Z-direction reference. Traditional rigid supports may cause elastic deformation of thin-walled or easily deformable workpieces 12 (such as aluminum alloys and plastic parts) due to concentrated force. The flexible floating support mechanism 4 distributes the clamping force evenly to the workpiece 12 through multi-point distributed support, significantly reducing the risk of deformation. During milling, the workpiece 12 may experience slight vibrations due to cutting forces. The floating support end 41 can move dynamically with the workpiece 12, providing continuous support, suppressing the vibration amplitude, thereby improving surface roughness and dimensional accuracy.

[0021] like Figure 3 As shown, the flexible floating support mechanism 4 is located in the central region of the fixture carrier plate 3. During machining, the clamping jaw mechanism 7 and the side-pushing clamping mechanism 10 typically act on the edge areas (such as the four corners or long sides). If the central region lacks support, the workpiece 12 may experience a cantilever beam effect due to its own weight or cutting force, leading to sagging or vibration in the central region. The flexible floating support mechanism 4, located in the central region, forms a force balance system of "edge clamping + central support," reducing the deformation of the workpiece 12 by more than 50%.

[0022] like Figure 3As shown, the top of the flexible floating support mechanism 4 has a cross-shaped channel 42. This cross-shaped channel 42 extends along the central axis of the top of the flexible floating support mechanism 4, and its two channel arms are respectively arranged along the length and width directions of the support end 41, dividing the support end 41 into four structurally symmetrical and independently load-bearing support areas 43. The cross-shaped channel 42 divides the support end 41 into four symmetrical and independently load-bearing areas, each of which can individually adapt to local deformation of the workpiece 12 surface. The design of the independent load-bearing areas reduces the excessive restriction of the workpiece 12's degrees of freedom by the support mechanism. In scenarios where it is necessary to retain a small floating space for the workpiece 12, the four support areas 43 can work together to provide Z-axis support force, while allowing the workpiece 12 to undergo small displacements in the X / Y directions due to thermal expansion and contraction, preventing stress concentration or cracking caused by constraint overload. The symmetrical layout of the cross-shaped channel 42 evenly distributes the support force to the four areas, avoiding single-point overload.

[0023] like Figure 1 and 3 As shown, the top surface of the support end 41 of the flexible floating support mechanism 4 is higher than the upper surface of the Z-direction positioning support block 9 in the initial state; in the initial state, the flexible support end 41 is higher than the Z-direction positioning support block 9, and the workpiece 12 first contacts the flexible support end 41 when it is placed. Before the clamping claw mechanism 7 clamps, the flexible support end 41 applies pre-pressure to the workpiece 12 through elastic deformation to eliminate the slight warping or gaps caused by the workpiece 12's own weight or residual stress.

[0024] like Figure 1 As shown, the side-push clamping mechanism 10 includes a cylinder support block 6, a second cylinder 5, and a clamping block 11. The cylinder support block 6 is fixed to the lower end of the fixture base 1. The tail of the second cylinder 5 is hinged to the cylinder support block 6. One end of the clamping block 11 is hinged to the front end of the piston rod of the second cylinder 5. The tail of the second cylinder 5 is hinged to the cylinder support block 6, and the front end of the piston rod is hinged to the clamping block 11, forming a double-hinged parallelogram mechanism. When the cylinder extends or retracts, the clamping block 11 translates along a fixed trajectory, avoiding the positioning error caused by angular deviation in traditional direct-push cylinders. The cylinder support block 6 is fixed to the lower end of the fixture base 1, and its initial position can be preset by adjusting its installation position. After the workpiece 12 is placed, the cylinder gently pushes the clamping block 11 to contact the side wall of the workpiece 12, using an elastic element to provide a small pre-pressure, eliminating the gap between the workpiece 12 and the clamping block 11, achieving "soft contact" positioning, and avoiding the workpiece 12 shifting due to hard collision.

[0025] like Figure 1 and Figure 2As shown, three side-push clamping mechanisms 10 are mounted on the fixture carrier plate 3, and the movement direction of their clamping ends is parallel to the plane of the fixture carrier plate 3. They are used to clamp the workpiece 12 from the X and Y directions. The three side-push clamping mechanisms 10 are symmetrically arranged along the X and Y directions. Through the synchronous translational movement of the clamping ends, they apply positioning force to the workpiece 12 from two orthogonal directions, thereby achieving absolute position locking of the workpiece 12 on the fixture carrier plate 3.

[0026] like Figure 2 As shown, twelve Z-axis positioning support blocks 9 are distributed in the corner area of ​​the workpiece 12; the Z-axis positioning support blocks 9 restrict the Z-axis translation and rotation around the X / Y axis of the workpiece 12 through at least 3 non-collinear support points; the Z-axis positioning support blocks 9 evenly distribute the force applied by the side push clamping mechanism 10 and the pressure claw mechanism 7 to the bottom of the workpiece 12 to avoid local stress concentration.

[0027] like Figure 1 As shown, the pressure claw mechanism 7 includes a first cylinder 51 and a pressure claw 71. The pressure claw 71 is rotatably connected to the fixture base 1. One end of the pressure claw 71 is hinged to the front end of the piston rod of the first cylinder 51. When the piston rod of the first cylinder 51 extends, it pushes the hinged end of the pressure claw 71 to move, pressing the workpiece 12 placed on the fixture to ensure that the workpiece 12 is stable in position during processing, inspection or assembly processes and avoids displacement.

[0028] Furthermore, in one embodiment of this utility model, there are nine equal-height support columns 2, which are evenly fixed at the edge of the fixture base 1. The fixture carrier plate 3 is fixedly installed on the top of the nine equal-height support columns 2 by fasteners. Six support columns are evenly distributed on the edge of the fixture base 1, forming a redundant support structure in which three points determine the plane. The weight of the workpiece 12 is evenly distributed to each support column, so that the parallelism error between the bottom surface of the workpiece 12 and the support surface is controlled within ±0.005mm, which meets the benchmark requirements for high-precision machining.

[0029] Working principle: In the initial state, the support end 41 of the flexible floating support mechanism 4 is raised, the pressure claw 71 is in a horizontally open state, and the side-push clamping mechanism 10 is in a retracted state. The workpiece 12 is placed into the fixture, so that its side contacts the side positioning block 8 for coarse positioning, and the middle of the workpiece 12 rests on the support end 41 of the flexible floating support mechanism 4. The four first cylinders 51 are activated at the same time, the piston rods extend, and drive the pressure claw 71 to rotate and press down, pressing the workpiece 12 tightly on the Z-direction positioning support block 9. Then the four second cylinders 5 are activated at the same time, and the side-push clamping mechanism 10 is activated, pushing the workpiece 12 from four directions, so that it is close to the side positioning block 8, completing the precise positioning. The control system of the flexible floating support mechanism 4 switches the air path, so that its support end 41 slowly descends under controlled conditions, driving the middle of the workpiece 12 to move down until the bottom surface of the workpiece 12 is completely in contact with all four Z-direction positioning support blocks 9. At this point, the original flatness error of workpiece 12 is corrected; then, pressure is introduced into the locking air passage to completely lock the support end 41 of the flexible floating support mechanism 4, making it a rigid fulcrum; the first cylinder 51 of the pressure claw mechanism 7 retracts, driving the pressure claw 71 to rotate and lift, separating it from workpiece 12; the CNC machine tool begins to process the upper surface of workpiece 12; after processing is completed, the side push clamping mechanism 10 is released, and the processed workpiece 12 can be taken out.

[0030] In summary, this adaptive flexible floating fixture for CNC milling machine planar machining automatically adapts to the flatness error of the incoming workpiece 12 through a centrally floating and lockable flexible floating support mechanism 4. During clamping, it stress-free corrects the workpiece to a state of complete contact with the Z-axis reference surface of the fixture, fundamentally eliminating machining deformation caused by clamping stress. This significantly reduces the defect rate of products due to uneven material thickness and overcutting caused by incoming material flatness issues, ensuring the quality stability and consistency of batch processing. During machining, the flexible floating support mechanism 4 is locked, forming a stable rigid support system together with the surrounding equal-height support columns 2 and Z-axis positioning support blocks 9, ensuring overall rigidity during machining and preventing tool vibration. The entire clamping process can be controlled by a PLC program, with sequential actions, reducing manual intervention, improving production efficiency, and reducing reliance on operator skills.

[0031] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0032] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A CNC milling machine planar machining adaptive flexible floating fixture, comprising a fixture base (1), a fixture carrier plate (3), multiple equal-height support columns (2) fixed on the fixture base (1) for supporting the fixture carrier plate (3), multiple lateral positioning blocks (8) disposed on the fixture carrier plate (3) for side positioning of a workpiece (12), multiple Z-direction positioning support blocks (9) disposed on the fixture carrier plate (3) for forming a Z-direction reference plane of the workpiece (12), multiple clamping jaw mechanisms (7) for clamping the workpiece (12), and multiple side-pushing clamping mechanisms (10) for clamping the workpiece (12) from the side, characterized in that: It also includes at least one flexible floating support mechanism (4); the bottom of the flexible floating support mechanism (4) is fixed on the jig base (1), and its top is provided with a floating and lockable support end (41), which penetrates the jig carrier plate (3) and protrudes from its upper surface.

2. The adaptive flexible floating fixture for CNC milling machine planar machining according to claim 1, characterized in that: The flexible floating support mechanism (4) is located in the middle region of the fixture carrier plate (3).

3. The adaptive flexible floating fixture for CNC milling machine planar machining according to claim 1, characterized in that: The top of the flexible floating support mechanism (4) is provided with a cross-shaped channel (42). The cross-shaped channel (42) extends along the central axis of the top of the flexible floating support mechanism (4), and its two channel arms are respectively set along the length and width directions of the support end (41), dividing the support end (41) into four structurally symmetrical and independently load-bearing support areas (43).

4. The adaptive flexible floating fixture for CNC milling machine planar machining according to claim 3, characterized in that: The top surface height of the support end (41) of the flexible floating support mechanism (4) is higher than the upper surface of the Z-direction positioning support block (9) in the initial state.

5. The adaptive flexible floating fixture for planar machining on a CNC milling machine according to claim 1, characterized in that: The side-push clamping mechanism (10) includes a cylinder support block (6), a second cylinder (5), and a clamping block (11); the cylinder support block (6) is fixed to the lower end of the fixture base (1); the tail of the second cylinder (5) is hinged to the cylinder support block (6); one end of the clamping block (11) is hinged to the front end of the piston rod of the second cylinder (5).

6. The adaptive flexible floating fixture for planar machining on a CNC milling machine according to claim 5, characterized in that: The plurality of side-push clamping mechanisms (10) are mounted on the fixture carrier plate (3), and the movement direction of their clamping ends is parallel to the plane of the fixture carrier plate (3), for clamping the workpiece (12) from the X and Y directions.

7. The adaptive flexible floating fixture for planar machining on a CNC milling machine according to claim 1, characterized in that: The plurality of Z-axis positioning support blocks (9) are distributed in the corner areas of the workpiece (12).

8. The adaptive flexible floating fixture for planar machining on a CNC milling machine according to claim 1, characterized in that: The pressure claw mechanism (7) includes a first cylinder (51) and a pressure claw (71). The pressure claw (71) is rotatably connected to the fixture base (1). One end of the pressure claw (71) is hinged to the front end of the piston rod of the first cylinder (51).

9. The adaptive flexible floating fixture for planar machining on a CNC milling machine according to claim 1, characterized in that: There are six equal-height support columns (2), which are evenly fixed at the edge of the fixture base (1).

10. The adaptive flexible floating fixture for planar machining on a CNC milling machine according to claim 1, characterized in that: The fixture carrier plate (3) is fixedly installed on the top of the plurality of equal-height support columns (2) by fasteners.

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