Flexible fixture clamp for numerical control machining of metal parts

Abstract

This application discloses a flexible tooling fixture for CNC machining of metal parts, belonging to the technical field of machining tooling fixtures. It includes a base, multiple sets of support blocks, lateral limiting components, workpiece clamping components, support blocks, and a guide limiting assembly. The support blocks have elongated holes and are assembled to the base using fastening bolts. The guide limiting assembly includes a fixed support, a guide rod, a spacer sleeve, an elastic preload component, and an end locking component. The fixed support is detachably mounted on the base, and the guide rod is mounted on the fixed support. Two adjacent support blocks are sequentially fitted onto the guide rod, with a spacer sleeve sandwiched between each pair of adjacent support blocks. The elastic preload component and the end locking component are respectively fitted at both ends of the guide rod. The end locking component is located on the side of the elastic preload component away from the support blocks, causing the elastic preload component to press against the support blocks. This enables synchronous displacement of adjacent support blocks, improving workpiece machining positioning accuracy.

Description

Technical Field

[0001] This application relates to the field of machining tooling fixtures, and in particular to a flexible tooling fixture for CNC machining of metal parts. Background Technology

[0002] Unlike rigid special fixtures that can only hold a single type of workpiece, flexible tooling fixtures are a set of clamping fixtures that can be quickly adjusted and switched to adapt to a variety of workpieces with different shapes and sizes. Flexible tooling fixtures are mainly composed of a base, lateral limiting components, workpiece clamping components, and support pads. Flexible tooling fixtures rely on the cooperation of each component to complete the workpiece support, positioning constraint, and clamping fixation.

[0003] To balance the structural strength of the tooling with lightweight heat dissipation, the base and support pads are often made of dissimilar metals with different coefficients of thermal expansion. Ordinary round hole locking installation will generate compressive internal stress due to the difference in thermal expansion and contraction between the two, causing the pads to be skewed, fasteners to loosen, and positioning accuracy to decrease. The industry generally adopts the method of opening elongated holes in the pads, using the gap in the hole to achieve small sliding, in order to compensate for the difference in thermal deformation of dissimilar materials.

[0004] However, when each support pad is arranged independently, the sliding direction and displacement of each support pad are dispersed, and the multi-point support position is prone to shift. The relative position between each support point of the workpiece changes, and the relative dimensions of various processed structural features on the workpiece are prone to deviation, affecting the processing accuracy. Summary of the Invention

[0005] The purpose of this application is to provide a flexible tooling fixture for CNC machining of metal parts, which solves the problem of asynchronous thermal sliding and misalignment of support pads with elongated holes, resulting in poor workpiece machining dimensional accuracy, and improves workpiece machining accuracy and long-term tooling stability.

[0006] A flexible tooling fixture for CNC machining of metal parts is provided, including a base, multiple sets of support pads, lateral limiting components, and workpiece clamping components. The support pads are arranged above the base; the lateral limiting components are located at the lateral position of the workpiece; the workpiece clamping components are pressed onto the workpiece; the bottom of the support pads has an elongated hole, and a fastening bolt passes through the elongated hole and is threaded to the base; the base and the support pads are made of dissimilar materials with different coefficients of thermal expansion.

[0007] It also includes a guide and limit assembly, which includes a fixed support, a guide rod, a spacer sleeve, an elastic preload component, and an end locking component. The length direction of the elongated hole is consistent with the axial direction of the guide rod. The fixed support is detachably installed on the base, and the guide rod is mounted on the fixed support. Two adjacent support pads are sequentially fitted onto the guide rod, and a spacer sleeve is clamped between each pair of adjacent support pads. The elastic preload component and the end locking component are respectively fitted at both ends of the guide rod. The end locking component is located on the side of the elastic preload component away from the support pad, so that the elastic preload component presses against the support pad.

[0008] Furthermore, the end locking component includes a threaded bushing and a locking nut. The threaded bushings are respectively arranged at both ends of the guide rod, and the threaded bushings and the guide rod are connected by an interference fit. The outer wall of the threaded bushing is provided with an external thread, and the locking nut is threadedly assembled on the outer side of the threaded bushing. The inner end face of the locking nut is in contact with the elastic preload component.

[0009] Furthermore, both ends of the spacer sleeve are provided with annular flanges, the annular flanges have flange positioning holes, and the end face of the support pad has a pad pin hole, with the positioning pin passing through the flange positioning hole and the pad pin hole.

[0010] Furthermore, the fixed support includes a lower support part and an upper limiting part; the base surface is provided with a matrix of threaded mounting holes, the support part has an assembly through hole, and the fastening bolt passes through the assembly through hole and connects to the threaded mounting hole; the limiting part abuts against the guide rod and forms a limiting support for the guide rod.

[0011] Furthermore, buffer blocks are provided at both ends of the elongated hole at the bottom of the support pad.

[0012] Furthermore, a wear-resistant gasket is sandwiched between the end face of the support pad and the annular flange of the spacer sleeve, with the two sides of the wear-resistant gasket respectively attached to the end face of the support pad and the end face of the annular flange.

[0013] Furthermore, the elastic preload component is a disc spring.

[0014] Furthermore, the base is made of cast iron, and the support pads are made of aluminum alloy.

[0015] Beneficial technical effects

[0016] All support pads are locked in series by guide rods, spacer sleeves, and elastic pre-tightening components. When heated and deformed, adjacent pads slide synchronously, and the relative positions of adjacent support points remain unchanged. This avoids independent displacement and skew of individual support pads, stabilizes the workpiece support datum, and improves the dimensional accuracy of parts.

[0017] By using threaded bushings with interference fit at both ends of the guide rod, and in conjunction with the locking component at the outer end, the limit clamping is completed. The bushings can be replaced individually to adapt to guide rods of different specifications, making the spacing adjustment convenient and the tooling more versatile.

[0018] By inserting and engaging the annular flanges at both ends of the spacer sleeve with the support pad and the positioning pin, the support pad and the sleeve are circumferentially limited and locked. During operation, the support pad cannot deflect circumferentially on its own, further improving the dimensional accuracy of the parts. Attached Figure Description

[0019] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 A schematic diagram of the connection structure between the support pad with an elongated hole and the base provided in an embodiment of this application;

[0021] Figure 2 This is a schematic diagram of the overall structure of the flexible tooling fixture for CNC machining of metal parts provided in the embodiments of this application;

[0022] Figure 3 This is an assembly diagram of a pad block with a guide rod inserted through it, according to an embodiment of this application.

[0023] Figure 4 This is a schematic diagram of the internal structure of the guide and limit assembly according to an embodiment of this application;

[0024] Figure 5 for Figure 4 A magnified view of a portion of point a;

[0025] Figure 6 for Figure 4 A magnified view of a portion at point b in the middle;

[0026] Figure 7 This is a schematic diagram of the installation of the fixed support and the base in an embodiment of this application;

[0027] Figure 8 This is a schematic diagram of the structure of the buffer block in an embodiment of this application.

[0028] Figure label:

[0029] 1. Base; 11. Threaded mounting holes;

[0030] 2. Support pad; 21. Oblong hole; 22. Buffer block; 23. Step avoidance;

[0031] 3. Lateral limiting components;

[0032] 4. Workpiece clamping components;

[0033] 5. Tighten the bolts;

[0034] 61. Fixed support; 611. Support part; 612. Limiting part; 62. Guide rod; 63. Spacer sleeve; 631. Annular flange; 64. Elastic preload component; 65. End locking component; 651. Threaded bushing; 652. Locking nut;

[0035] 7. Wear-resistant gaskets;

[0036] 8. Positioning pins;

[0037] 9. Workpiece. Detailed Implementation

[0038] The technical solutions of the embodiments of this application will be described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments.

[0039] In embodiments of this application, 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 limitation, 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 that element.

[0040] In the embodiments of this application, unless otherwise explicitly specified and limited, the term "connection" should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral part; it can be a direct connection or an indirect connection through an intermediate medium.

[0041] See Figure 1 In various CNC machining applications, to balance the two different requirements of overall tooling structural stability and local support for heat dissipation and lightweighting, the industry typically selects dissimilar metal materials with different coefficients of thermal expansion for the base 1 and the support pad 2. Because the two components are made of different materials, their elongation and deformation after heating will also differ.

[0042] If the support pad 2 uses a standard circular mounting hole, and the fastening bolt 5 locks the support pad 2 in place, the two materials have different thermal expansion and contraction rates but no room to move, causing them to compress each other and generate a suffocating force. This can easily cause the support pad 2 to warp or tilt, resulting in a deterioration in the flatness of the support surface. Long-term repeated thermal compression can also cause the fastening connectors to loosen, leading to a continuous decrease in the overall positioning accuracy of the tooling. After the support pad 2 undergoes continuous deformation, the workpiece positioning will shift, and the stability of the final machining dimensions cannot be guaranteed.

[0043] The current industry standard solution is to open an elongated hole 21 on the support pad 2 and fix the fastening bolt 5 on the base 1. Relying on the gap reserved between the inner wall of the elongated hole 21 and the rod of the fastening bolt 5, the support pad 2 can slide slightly relative to the fastening bolt 5, thereby accommodating the thermal deformation of different materials.

[0044] For example, the fastening bolt 5 is a countersunk bolt, and an avoidance step 23 is provided on the inner side of the elongated hole 21 to accommodate the bolt head of the countersunk bolt. The minor diameter of the elongated hole 21 is consistent with the mounting hole diameter of the base 1. After the countersunk bolt passes through the mounting hole and the elongated hole 21 of the base, the bolt head is engaged with the avoidance step 23, thereby achieving a stable connection between the base 1 and the support pad 2.

[0045] In actual machining, the entire fixture usually selects a single support block 2 as the reference for all machining dimensions. Once the support blocks 2 move randomly and misaligned, the original reference correspondence is disrupted, and the overall positioning structure changes. If all the support blocks 2 can slide synchronously as a whole, the relative features of the internal structure of the workpiece can remain stable.

[0046] Example 1

[0047] See Figures 1-2This embodiment provides a flexible tooling fixture for CNC machining of metal parts, including a base 1, multiple sets of support pads 2, lateral limiting members 3, and workpiece clamping members 4. The support pads 2 are arranged above the base 1; the lateral limiting members 3 are located at the lateral position of the workpiece 9; the workpiece clamping members 4 are pressed onto the workpiece 9; the bottom of the support pads 2 has an elongated hole 21, and a fastening bolt 5 passes through the elongated hole 21 and is threaded to the base 1; the base 1 and the support pads 2 are made of dissimilar materials with different coefficients of thermal expansion; it also includes a guide and limiting assembly, which includes a fixed support 61, a guide rod 62, and a fixed distance. The guide rod 62 is equipped with a sleeve 63, an elastic pre-tightening member 64, and an end locking member 65. The length direction of the elongated hole 21 is consistent with the axial direction of the guide rod 62. The fixed support 61 is detachably installed on the base 1, and the guide rod 62 is mounted on the fixed support 61. Two adjacent support pads 2 are sequentially sleeved on the guide rod 62, and a fixed sleeve 63 is sandwiched between each of the two adjacent support pads 2. The elastic pre-tightening member 64 and the end locking member 65 are respectively fitted at both ends of the guide rod 62. The end locking member 65 is located on the side of the elastic pre-tightening member 64 away from the support pad 2, so that the elastic pre-tightening member 64 presses the support pad 2.

[0048] Understandably, base 1 serves as the overall support base for the tooling, accommodating the support pad 2, lateral limiting member 3, and workpiece clamping member 4. The support pad 2 is positioned above base 1 to support the workpiece 9 from below. The lateral limiting member 3 is positioned laterally on the workpiece 9 to prevent lateral displacement. The workpiece clamping member 4 is pressed onto the workpiece 9 to press it firmly against the support pad 2. The workpiece 9 is clamped between the lateral limiting member 3, the workpiece clamping member 4, and the support pad 2.

[0049] Understandably, the guide limit assembly is an integrated component that provides axial guidance, spacing positioning, and pre-tightening constraint for adjacent support pads 2; the length direction of the elongated hole 21 is the same as the axial direction of the guide rod 62, so that the support pads 2 can only slide along the direction of the guide rod 62 for thermal compensation, avoiding free sliding in any direction; the spacer sleeve 63 is a hollow sleeve part that is fitted on the outside of the guide rod 62 and strictly controls the center distance between two adjacent support pads 2; the elastic pre-tightening member 64 is an elastic element that can continuously output axial elastic force; the end locking member 65 is installed at both ends of the guide rod 62 to lock the overall axial pre-tightening force.

[0050] For example, multiple support pads 2 are sequentially strung along the guide rod 62, with a spacer sleeve 63 placed between each pair of adjacent support pads 2 for interval positioning. The elastic pre-tightening members 64 at both ends of the guide rod 62 continuously press the support pads 2, and the adjacent support pads 2 are tightly pressed against the spacer sleeves 63 without gaps. Each support pad 2 is individually fitted onto the outside of the fastening bolts 5 of the base 1 by its own elongated hole 21, and has directional sliding allowance.

[0051] Understandably, the elastic preload member 64 applies a moderate preload force to the end face of the support pad 2, and a small sliding gap is maintained between the components; under the constraint of the spacer sleeve 63, the spacing between the support pads 2 remains constant. When thermal expansion occurs, the entire assembly can slide slightly in the same direction synchronously, and the spacing between adjacent support pads 2 is constantly constrained by the spacer sleeve 63, preventing loosening and separation.

[0052] It is worth noting that the elongated hole 21 of the support pad 2 is aligned with the direction of the guide rod 62, ensuring that adjacent support pads 2 move synchronously along the guide rod 62. The end locking member 65 remains fixed relative to the base 1, and the elastic pre-tightening member 64 is in a compressed state to provide a certain pre-tightening force. At this time, the elastic pre-tightening member 64 still has some room for movement, and the support pad 2 can still slide along the guide rod 62. If the support pad 2 slides closer to the end locking member 65, the elastic pre-tightening member 64 can be further compressed to match the movement stroke of the support pad 2.

[0053] The guide rod 62 uniformly limits the sliding path of adjacent support pads 2, allowing them to move only along the axial direction of the guide rod 62, preventing arbitrary lateral and radial offsets. The spacer sleeve 63 locks the fixed distance between adjacent support pads 2, ensuring that the relative positions of various processed structural features of the workpiece 9 remain unchanged. Simultaneously, the elongated hole 21 effectively releases the internal stress caused by the thermal expansion difference between the base 1 and the support pads 2, preventing the support pads 2 from warping and detaching from the reference surface, while ensuring that the multi-point support reference changes synchronously, resulting in stable and uniform processing dimensions for the workpiece 9.

[0054] Example 2

[0055] See Figures 4-5 The end locking member 65 includes a threaded bushing 651 and a locking nut 652. The threaded bushing 651 is respectively arranged at both ends of the guide rod 62, and the threaded bushing 651 and the guide rod 62 are connected by interference fit. The outer wall of the threaded bushing 651 is provided with external thread, and the locking nut 652 is threadedly fitted to the outer side of the threaded bushing 651. The inner end face of the locking nut 652 is attached to the elastic preload member 64.

[0056] Understandably, the threaded bushing 651 is an annular assembly with a complete external thread machined on the outside. It is fastened to both ends of the guide rod 62 by interference fit, forming a stable threaded installation base. The locking nut 652 meshes with the external thread of the threaded bushing 651, and the end face of the locking nut 652 presses against the elastic preload member 64.

[0057] For example, interference fit can be achieved using various conventional processes such as room temperature press fitting, hot fitting with heated expansion holes, and cold shrinking shaft, to ensure that there is no relative rotation or axial movement between the threaded bushing 651 and the guide rod 62.

[0058] For example, after heating the threaded bushing 651, it is fitted onto both ends of the guide rod 62. After cooling and shrinking, a firm interference fit is achieved. Then, the locking nut is screwed in, and the overall preload pressure is adjusted by the depth of the locking nut.

[0059] The guide rod 62 and the threaded bushing 651 adopt a split interference fit structure, which eliminates the need to machine threads on the guide rod 62. The spacing of the support pads 2 can be flexibly adjusted, which can adapt to various specifications of workpieces. The tooling is highly versatile and easy to disassemble, assemble, and debug. The clamping force can be continuously finely adjusted by locking the nut 652 to ensure that the preload at both ends of the guide rod 62 is symmetrical and uniform. The interference fit connection is reliable, and various assembly processes can be realized. The overall locking structure is stable and durable.

[0060] Alternatively, external threads can be machined directly at both ends of the guide rod 62, eliminating the independent threaded bushing 651, and the locking nut 652 can be directly screwed onto the threaded section of the guide rod 62 to press the elastic preload member 64.

[0061] Example 3

[0062] See Figure 6 Both ends of the spacer sleeve 63 are provided with annular flanges 631, and the annular flanges 631 are provided with flange positioning holes. The end face of the support pad 2 is provided with pad pin holes, and the positioning pin passes through the flange positioning holes and the pad pin holes.

[0063] For example, the annular flange 631 is integrally formed at both ends of the spacer sleeve 63, and its outer diameter is larger than that of the spacer sleeve 63 body; the positioning pin 8 is a cylindrical positioning structure protruding on the mating end face of the support pad 2. When the adjacent support pad 2 and the spacer sleeve 63 are mated, the positioning pin 8 on the support pad 2 is accurately inserted into the flange positioning hole and the pad pin hole, so that the support pad 2 and the spacer sleeve 63 are locked in circumferential position.

[0064] The annular flange 631 increases the pressure-bearing contact area between the support pad 2 and the spacer sleeve 63, reducing local compressive stress; the positioning pin 8 is inserted into the flange positioning hole and the pad pin hole to prevent the support pad 2 from circumferentially twisting relative to the spacer sleeve 63, so that the posture of the entire support assembly remains consistent.

[0065] Adjacent support pads 2 are tightly connected to the elastic preload member 64 via spacer sleeves to form an integral unit, creating mutual constraints between the components. When a support pad 2 deforms due to heat, even if it tends to deflect, it will deflect synchronously and in the same direction as the adjacent support pads 2, preventing any individual support pad 2 from tilting or misaligning. The relative dimensions and positional relationships between the components within the entire structure remain unchanged, ensuring a stable geometric layout of the workpiece's support points, maintaining long-term positioning accuracy, and further reducing machining errors.

[0066] Example 4

[0067] See Figure 7 The fixed support 61 includes a lower support part 611 and an upper limiting part 612; the base 1 has a matrix of threaded mounting holes 11 on its surface, the support part 611 has an assembly through hole, and the fastening bolt 5 passes through the assembly through hole and is connected to the threaded mounting hole 11; the limiting part 612 abuts against the guide rod 62 and forms a limiting support for the guide rod 62.

[0068] Understandably, the base 1 has a number of threaded mounting holes 11 evenly arranged in a matrix pattern, allowing the fixed supports 61 to freely choose their mounting points; the limiting part 612 supports the guide rod 62 by means of a groove structure. For example, based on the overall length of the support pads 2, threaded mounting holes 11 at appropriate positions on the base 1 are selected to fix each fixed support 61, and the upper limiting part 612 holds the guide rod 62 in a slot. Multiple fixed supports 61 can be provided to be installed on the base 1.

[0069] The matrix-arranged threaded mounting holes 11 of the base 1 can flexibly change the installation position of the fixed support 61, and adapt to support pad 2 components with different total lengths and different arrangement spacings, making the tooling more versatile; the support part 611 ensures that the fixed support 61 is firmly fixed on the base 1, and the upper limiting part 612 restricts the guide rod 62 from swaying up and down and left and right, making the entire set of guide references stable and reliable, and ensuring that the sliding direction of adjacent support pads 2 is accurate and uniform.

[0070] Example 5

[0071] See Figure 8 The support pad 2 has buffer blocks 22 at both ends of the elongated hole 21 at the bottom.

[0072] Understandably, the buffer block 22 is installed on the inner wall of the two extreme ends of the elongated hole 21, in an area where the screw of the fastening bolt 5 is prone to collide with the inner wall of the elongated hole 21. For example, when the support pad 2 slides to the maximum stroke position of the elongated hole 21 after being heated, the buffer block 22 contacts the screw of the fastening bolt 5 first, rather than the base of the support pad 2 directly hitting the screw.

[0073] For example, the buffer block 22 is made of a soft, elastic material such as silicone, which serves to cushion and absorb shock. The buffer block 22 and the support pad 2 with the elongated hole 21 can be connected by any method such as bonding, embedding, or snap-fitting, and this embodiment does not specifically limit this.

[0074] The buffer block 22 can absorb the impact force when the support pad 2 is displaced to the limit position, eliminate the impact vibration caused by metal collision, and prevent the support pad 2 from shifting its posture due to instantaneous force. At the same time, it can reduce the slight back-and-forth movement of the support pad 2 under cutting vibration, resulting in better dynamic stability of the support reference and higher machining dimensional accuracy of the workpiece 9.

[0075] Example 6

[0076] A wear-resistant gasket 7 is sandwiched between the end face of the support block 2 and the annular flange 631 of the spacer sleeve 63. The two sides of the wear-resistant gasket 7 are respectively pressed against the end face of the support block 2 and the end face of the annular flange 631.

[0077] Understandably, the wear-resistant gasket 7 is a thin, wear-resistant part, separately installed between the end face of the support pad 2 and the two mating surfaces of the spacer sleeve 63 and the annular flange 631. For example, when the support pad 2 and the annular flange 631 are pressed together, the wear-resistant gasket 7 is sandwiched between them, separating the end face of the spacer sleeve 63 from the end face of the support pad 2.

[0078] The wear-resistant pad 7 separates the contact surfaces of the spacer sleeve 63 and the support pad 2, preventing long-term friction between the two parts from causing end face wear. When the support pad 2 slides slightly along the axial direction, the wear-resistant pad 7 has low friction characteristics, slides smoothly without jamming, and after long-term use, the distance between the support pad 2 and the spacer sleeve 63 remains accurate, and the relative dimensional relationship of the entire assembly remains stable over a long period of time.

[0079] Example 7

[0080] See Figure 5 The elastic preload component 64 is a butterfly spring.

[0081] Understandably, the disc spring is a disc-shaped conical elastic washer that can be used individually or in combination of multiple pieces, and is fitted onto the outer sides of both ends of the guide rod 62. For example, multiple sets of disc springs are stacked and placed between the locking nut 652 and the support pad 2, relying on their own elastic deformation to continuously provide clamping force.

[0082] The disc spring occupies little axial space and can output a stable and large clamping load. When the axial dimension of the entire assembly changes slightly after heating, the disc spring can adaptively compensate for the slight expansion and contraction, maintaining the overall linkage synchronization.

[0083] Optionally, the elastic preload member 64 can also be a wave spring, cylindrical spring, etc.

[0084] Example 8

[0085] The base 1 is made of cast iron, and the support pad 2 is made of aluminum alloy.

[0086] It is understandable that cast iron has high rigidity and excellent vibration reduction performance, making it suitable as the base for bearing the entire tooling; aluminum alloy is lighter and has a faster heat dissipation during cutting, so it is often used to make multi-point support pads. The two have different coefficients of thermal expansion.

[0087] Alternatively, in addition to cast iron paired with aluminum alloy, any two dissimilar metal materials with a difference in thermal expansion coefficients can be selected for use depending on the actual working conditions.

[0088] The cast iron base 1 has a small amount of thermal deformation, and the overall basic reference of the tooling is stable and reliable; the aluminum alloy support pad 2 is lightweight, with a lower overall load and high heat dissipation efficiency; the stress generated by the thermal expansion difference between the two materials is released by the directional synchronous sliding structure of the elongated hole 21, which can give full play to the performance advantages of the two materials respectively, and will not cause the single-point support to warp or the reference to be disordered due to the inconsistent deformation of different materials.

[0089] The above are merely preferred embodiments of this application and are not intended to limit the scope of protection of this application. Any modifications, equivalent substitutions, improvements, etc., made within the concept and principles of this application should be included within the scope of protection of this application.

[0090] In the description of the embodiments of this application, specific features, structures, materials or characteristics may be combined in any suitable manner in one or more embodiments or examples.

[0091] The above are merely specific embodiments of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A flexible tooling fixture for CNC machining of metal parts, comprising a base, multiple sets of support pads, lateral limiting components, and workpiece clamping components, wherein the support pads are arranged above the base; the lateral limiting components are located at the lateral position of the workpiece; the workpiece clamping components are pressed onto the workpiece; the bottom of each support pad has an elongated hole, and a fastening bolt passes through the elongated hole, the fastening bolt being threaded to the base; the base and the support pads are made of dissimilar materials with different coefficients of thermal expansion; Its features are, It also includes a guide and limiting assembly, which includes a fixed support, a guide rod, a spacer sleeve, an elastic preload member, and an end locking member. The length direction of the elongated hole is consistent with the axial direction of the guide rod. The fixed support is detachably installed on the base, and the guide rod is mounted on the fixed support. Two adjacent support pads are sequentially sleeved on the guide rod, and the spacer sleeve is sandwiched between each pair of adjacent support pads. The elastic preload member and the end locking member are respectively fitted at both ends of the guide rod. The end locking member is located on the side of the elastic preload member away from the support pad, so that the elastic preload member presses against the support pad.

2. The flexible tooling fixture for CNC machining of metal parts according to claim 1, characterized in that, The end locking component includes a threaded bushing and a locking nut. The threaded bushing is respectively arranged at both ends of the guide rod, and the threaded bushing and the guide rod are connected by an interference fit. The outer wall of the threaded bushing is provided with an external thread, and the locking nut is threadedly assembled on the outer side of the threaded bushing. The inner end face of the locking nut is in contact with the elastic preload component.

3. The flexible tooling fixture for CNC machining of metal parts according to claim 1, characterized in that, Both ends of the spacer sleeve are provided with annular flanges, the annular flanges are provided with flange positioning holes, and the end face of the support pad is provided with a pad pin hole. The positioning pin passes through the flange positioning hole and the pad pin hole.

4. The flexible tooling fixture for CNC machining of metal parts according to claim 1, characterized in that, The fixed support includes a lower support part and an upper limiting part; the base surface is provided with a matrix of threaded mounting holes, the support part has an assembly through hole, the fastening bolt passes through the assembly through hole and is connected to the threaded mounting hole; the limiting part abuts against and supports the guide rod, forming a limiting support for the guide rod.

5. The flexible tooling fixture for CNC machining of metal parts according to claim 1, characterized in that, The support pad has buffer blocks at both ends of the elongated hole at the bottom.

6. The flexible tooling fixture for CNC machining of metal parts according to claim 3, characterized in that, A wear-resistant gasket is sandwiched between the end face of the support pad and the annular flange of the spacer sleeve, with the two sides of the wear-resistant gasket respectively attached to the end face of the support pad and the end face of the annular flange.

7. The flexible tooling fixture for CNC machining of metal parts according to claim 1, characterized in that, The elastic preload component is a disc spring.

8. The flexible tooling fixture for CNC machining of metal parts according to claim 1, characterized in that, The base is made of cast iron, and the support pad is made of aluminum alloy.

Images