Multi-degree-of-freedom self-adaptive positioning clamp for machining special-shaped mechanical parts

Abstract

The invention relates to the technical field of positioning clamps, in particular to a multi-degree-of-freedom self-adaptive positioning clamp for machining special-shaped mechanical parts, which comprises a base, a bottom plate and a clamping connecting assembly, the clamping connecting assembly comprises an air cylinder, a push rod, a moving plate, a connecting base, a ball, a buffer pad, a controller, four sets of reset components, a monitoring component, a horizontal adjusting component and a scanning auxiliary component, the scanning auxiliary component obtains initial three-dimensional point cloud data of a workpiece, the horizontal adjusting component adjusts the levelness of a bottom plate, and the controller controls the air cylinder to act according to the point cloud data; the push rod is driven to extend out, so that the ball pushes the connecting seat to drive the moving plate to move towards the workpiece; the reset component provides pulling force and reset force for the connecting base to overturn around the ball, the buffer cushion can be attached to the curved surface of the workpiece in a self-adaptive mode, through cooperation of the clamping connecting assembly, the base and the bottom plate, uniform stress is achieved, workpiece deformation is prevented, and therefore the adaptability problem of a traditional rigid positioning element is solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of positioning clamps, in particular to a multi-degree-of-freedom self-adaptive positioning clamp for machining of special-shaped mechanical parts. BACKGROUND

[0002] With the development of high-end equipment manufacturing industry, special-shaped mechanical parts (such as aerospace engine blades, precision hydraulic valve bodies, complex molds and other parts with free-form surfaces, multiple datum features or irregular structures) are increasingly widely used. The machining quality of such parts directly affects the performance and reliability of the overall equipment. However, efficient and high-precision clamping and positioning of such parts during numerical control machining has always been a bottleneck problem restricting production efficiency and process level.

[0003] At present, the clamping of special-shaped parts mainly uses general combined clamps, which include general clamps such as vices and three-jaw chucks or modular combined clamps, and can achieve clamping of special-shaped mechanical parts.

[0004] However, in the foregoing prior art, the rigid positioning elements are difficult to adaptively fit the complex curved surface of the workpiece, and are prone to point contact or line contact, resulting in unstable positioning, poor repeatability, and workpiece deformation or stress concentration during locking, which causes damage to the workpiece. SUMMARY

[0005] The present application aims to provide a multi-degree-of-freedom self-adaptive positioning clamp for machining of special-shaped mechanical parts, which solves the problem of rigid positioning elements in the prior art being difficult to adaptively fit the complex curved surface of the workpiece, prone to point contact or line contact, resulting in unstable positioning, poor repeatability, and workpiece deformation or stress concentration during locking, which causes damage to the workpiece.

[0006] In order to achieve the above object, the application provides a multi-degree-of-freedom self-adaptive positioning clamp for special-shaped mechanical accessory machining, which comprises a base, a bottom plate and a clamping connecting assembly, the clamping connecting assembly comprises a pneumatic cylinder, a push rod, a moving plate, a connecting seat, a ball, a buffer pad, a controller, four sets of reset components, a monitoring component, a horizontal adjusting component and a scanning auxiliary component, the bottom plate is arranged above the base, and the clamping connecting assembly is connected with the bottom plate and the base respectively; the pneumatic cylinder is detachably connected with the base and located above the bottom plate, the push rod is fixedly connected with the pneumatic cylinder and located at the output end of the pneumatic cylinder, the ball is fixedly connected with the push rod and located at one end of the push rod, the moving plate is arranged on one side of the ball, the connecting seat is fixedly connected with the moving plate and located on one side of the moving plate, and the connecting seat is rotationally matched with the ball, the buffer pad is fixedly connected with the moving plate and located on the other side of the moving plate, the controller is arranged on one side of the base, the monitoring component is connected with the buffer pad, four sets of the reset components are connected with the moving plate and the push rod respectively, the horizontal adjusting component is connected with the base and the bottom plate respectively, and the scanning auxiliary component is connected with the base.

[0007] The clamping connecting assembly further comprises a roller seat, the roller seat is rotationally connected with the moving plate and located below the moving plate, and the roller seat is in contact with the bottom plate.

[0008] The reset component comprises a first fixed ring, a second fixed ring and a tension spring, the first fixed ring is fixedly connected with the moving plate and located on one side of the moving plate, the second fixed ring is fixedly connected with the push rod and located on the outer side wall of the push rod, and the two ends of the tension spring are detachably connected with the first fixed ring and the second fixed ring respectively.

[0009] The monitoring component comprises a pressure sensor and a displacement sensor, the pressure sensor is arranged on the inner side wall of the buffer pad, the displacement sensor is fixedly connected with the moving plate and located below the moving plate, and the pressure sensor and the displacement sensor are electrically connected with the controller respectively.

[0010] The horizontal adjusting component comprises a support ball rod, a universal seat and four sets of adjusting pieces, the support ball rod is fixedly connected with the base and located above the base, the universal seat is fixedly connected with the bottom plate and located below the bottom plate, the universal seat is rotationally matched with the support ball rod, and four sets of the adjusting pieces are connected with the base and the bottom plate respectively.

[0011] The adjusting piece comprises a base, a hydraulic cylinder and a top seat, the base is fixedly connected with the base and located above the base, the top seat is fixedly connected with the bottom plate and located below the bottom plate, the bottom end of the hydraulic cylinder is rotationally connected with the base, and the output end of the hydraulic cylinder is rotationally connected with the top seat.

[0012] The scanning auxiliary member comprises a support and a visual sensor, the support is fixedly connected with the base and located above the base, the visual sensor is detachably connected with the support and located below the support, and the visual sensor is electrically connected with the controller.

[0013] The application discloses a multi-freedom-degree self-adaptive positioning clamp for special-shaped mechanical accessory machining. BRIEF DESCRIPTION OF DRAWINGS

[0014] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced.

[0015] Figure 1 FIG. 1 is a structural schematic diagram of the multi-freedom-degree self-adaptive positioning clamp for special-shaped mechanical accessory machining.

[0016] Figure 2 FIG. 2 is a front view of the multi-freedom-degree self-adaptive positioning clamp for special-shaped mechanical accessory machining.

[0017] Figure 3 FIG. 3 is a sectional view of the A-A line of the multi-freedom-degree self-adaptive positioning clamp for special-shaped mechanical accessory machining. Figure 2

[0018] FIG. 4 is an enlarged view of the local structure at B of the multi-freedom-degree self-adaptive positioning clamp for special-shaped mechanical accessory machining. Figure 4 Figure 3 FIG. 5 is a sectional view of the B-B line of the multi-freedom-degree self-adaptive positioning clamp for special-shaped mechanical accessory machining.​

[0019] 101-Base, 102-Base plate, 103-Cylinder, 104-Push rod, 105-Moving plate, 106-Connecting seat, 107-Spherical ball, 108-Buffer pad, 109-Controller, 110-Roller seat, 111-First fixing ring, 112-Second fixing ring, 113-Tension spring, 114-Pressure sensor, 115-Displacement sensor, 116-Supporting ball rod, 117-Universal seat, 118-Base, 119-Hydraulic cylinder, 120-Top seat, 121-Bracket, 122-Vision sensor, 123-Fixing rod, 124-Right angle plate, 125-Locking bolt. Detailed Implementation

[0020] The embodiments of the present invention are described in detail below. Examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, but should not be construed as limiting the present invention.

[0021] Please see Figures 1-4 , Figure 1 This is a schematic diagram of the multi-degree-of-freedom adaptive positioning fixture for machining irregularly shaped mechanical parts according to the present invention. Figure 2 This is a front view of the multi-degree-of-freedom adaptive positioning fixture for machining irregularly shaped mechanical parts according to the present invention. Figure 3 This is the invention Figure 2 AA-line sectional view, Figure 4 This is the invention Figure 3 Enlarged view of the local structure at point B.

[0022] This invention provides a multi-degree-of-freedom adaptive positioning fixture for machining irregularly shaped mechanical parts, comprising a base 101, a base plate 102, and a clamping connection assembly. The clamping connection assembly includes a cylinder 103, a push rod 104, a moving plate 105, a connecting seat 106, a ball 107, a buffer pad 108, a controller 109, a roller seat 110, four sets of reset components, a monitoring component, a leveling adjustment component, and a scanning auxiliary component. The reset components include a first fixing ring 111, a second fixing ring 112, and a tension spring 113. The monitoring component includes a pressure sensor 114 and a displacement sensor 115. The horizontal adjustment component includes a support ball rod 116, a universal joint 117, and four sets of adjustment components. The adjustment components include a base 118, a hydraulic cylinder 119, and a top seat 120. The scanning auxiliary component includes a bracket 121 and a vision sensor 122. The multi-degree-of-freedom adaptive positioning fixture for processing irregularly shaped mechanical parts also includes an installation assembly. The installation assembly includes a fixing rod 123, a right-angle plate 124, and a locking bolt 125.

[0023] The base plate 102 is disposed above the base 101, and the clamping connecting assembly is connected to both the base plate 102 and the base 101. The cylinder 103 is detachably connected to the base 101 and is located above the base plate 102. The push rod 104 is fixedly connected to the cylinder 103 and is located at the output end of the cylinder 103. The ball 107 is fixedly connected to the push rod 104 and is located at one end of the push rod 104. The moving plate 105 is disposed on one side of the ball 107, and the connecting seat 106 is fixedly connected to the moving plate 105. The connecting seat 106 is located on one side of the moving plate 105, and the connecting seat 106 is rotatably engaged with the ball 107. The buffer pad 108 is fixedly connected to the moving plate 105 and located on the other side of the moving plate 105. The controller 109 is located on one side of the base 101. The monitoring component is connected to the buffer pad 108. The four sets of reset components are respectively connected to the moving plate 105 and the push rod 104. The horizontal adjustment component is respectively connected to the base 101 and the bottom plate 102. The scanning auxiliary component is connected to the base 101.

[0024] In this embodiment, firstly, the scanning auxiliary component acquires the initial three-dimensional point cloud data of the irregularly shaped workpiece to be clamped and transmits the data to the controller 109; then, the leveling component adjusts the levelness of the base plate 102 to ensure the processing reference; during the clamping process, the controller 109 controls the cylinder 103 to move according to the point cloud data, driving the push rod 104 to extend, causing the ball 107 to push the connecting seat 106, thereby moving the moving plate 105 toward the workpiece; at this time, the reset component is located on one side of the moving plate 105. The connecting seat 106 rotates around the sphere 107 to provide tension and restoring force, enabling the buffer pad 108 to adaptively conform to the complex curved surface of the workpiece, avoiding rigid point contact or line contact. At the same time, the monitoring component provides real-time pressure and displacement data feedback to the controller 109 to assist in dynamically adjusting the clamping force, ensuring stable positioning and high repeatability. Finally, through the cooperation of the clamping connecting assembly, the base 101, and the base plate 102, uniform force is achieved, preventing workpiece deformation or stress concentration, thereby solving the compatibility problem of traditional rigid positioning elements.

[0025] Furthermore, the roller seat 110 is rotatably connected to the movable plate 105 and is located below the movable plate 105, and the roller seat 110 is in contact with the base plate 102.

[0026] In this embodiment, the roller seat 110 is used to support the movement of the movable plate 105 and ensure the stability of the movement of the movable plate 105.

[0027] Furthermore, the first fixing ring 111 is fixedly connected to the moving plate 105 and is located on one side of the moving plate 105, the second fixing ring 112 is fixedly connected to the push rod 104 and is located on the outer side wall of the push rod 104, and the two ends of the tension spring 113 are detachably connected to the first fixing ring 111 and the second fixing ring 112 respectively.

[0028] In this embodiment, when the buffer pad 108 contacts the outer wall of the irregularly shaped workpiece, the connecting seat 106 will rotate around the sphere 107 in multiple directions to adapt to the curved surface. At this time, the tension spring 113 located on the upper side of the moving plate 105 and connected by the first fixing ring 111 is stretched, while the corresponding tension spring 113 on the lower side will contract. At the same time, the tension springs 113 on the left and right sides will adaptively extend and retract according to the curvature of the workpiece surface. The mechanism of the four sets of tension springs 113 working together provides the necessary tension and multi-directional restoring force for the rotation of the connecting seat 106, ensuring that the buffer pad 108 can dynamically and flexibly maintain multi-point and multi-directional contact with the complex curved surface, thereby effectively dispersing pressure and avoiding local stress concentration.

[0029] Furthermore, the pressure sensor 114 is disposed on the inner sidewall of the buffer pad 108, the displacement sensor 115 is fixedly connected to the moving plate 105 and located below the moving plate 105, and the pressure sensor 114 and the displacement sensor 115 are electrically connected to the controller 109 respectively.

[0030] In this embodiment, the pressure sensor 114 is built into the inner wall of the buffer pad 108 to directly measure the normal pressure when it contacts the curved surface of the workpiece. The displacement sensor 115 is fixed below the moving plate 105 to accurately detect the overall displacement of the moving plate 105. The pressure and displacement signals collected by both sensors are transmitted to the controller 109 in real time.

[0031] Furthermore, the support rod 116 is fixedly connected to the base 101 and located above the base 101, the universal joint 117 is fixedly connected to the base plate 102 and located below the base plate 102, and the universal joint 117 is rotatably engaged with the support rod 116, and the four sets of adjusting components are respectively connected to the base 101 and the base plate 102.

[0032] In this embodiment, the support rod 116 is fixed above the base 101, and the universal joint 117 is fixed below the base plate 102. The two form a rotating pair through spherical engagement, allowing the base plate 102 to rotate freely during adjustment. The four sets of adjustment components are evenly distributed between the base 101 and the base plate 102. Through coordinated lifting and fine-tuning, the posture of the base plate 102 around the center point of the support rod 116 and the universal joint 117 is precisely controlled. During the clamping initialization phase, the controller 109 drives the adjustment components to move based on horizontal sensing data, so that the base plate 102 quickly reaches and locks into the required high level state, laying a solid foundation for subsequent adaptive clamping and processing based on three-dimensional point clouds.

[0033] Furthermore, the base 118 is fixedly connected to the base 101 and is located above the base 101, the top seat 120 is fixedly connected to the bottom plate 102 and is located below the bottom plate 102, the bottom end of the hydraulic cylinder 119 is rotatably connected to the base 118, and the output end of the hydraulic cylinder 119 is rotatably connected to the top seat 120.

[0034] In this embodiment, the controller 109 drives four sets of hydraulic cylinders 119 to extend and retract in coordination. Through the rotational connection at the top, the angle of the base plate 102 is adapted to change, thereby precisely adjusting the posture of the base plate 102 around the center of the ball joint to ensure that it reaches the required high level and is locked.

[0035] Furthermore, the bracket 121 is fixedly connected to the base 101 and is located above the base 101, the vision sensor 122 is detachably connected to the bracket 121 and is located below the bracket 121, and the vision sensor 122 is electrically connected to the controller 109.

[0036] In this embodiment, the vision sensor 122 located below the bracket 121 is used to acquire the initial three-dimensional point cloud data of the irregularly shaped workpiece to be clamped.

[0037] Furthermore, the multi-degree-of-freedom adaptive positioning fixture for processing irregularly shaped mechanical parts also includes an installation assembly. The installation assembly includes a fixing rod 123, a right-angle plate 124, and a locking bolt 125. The fixing rod 123 is fixedly connected to the base 101 and is located above the base 101. The right-angle plate 124 is rotatably connected to the fixing rod 123 and is located on the outer side wall of the fixing rod 123. The locking bolt 125 is threadedly connected to the right-angle plate 124.

[0038] In this embodiment, the base 101 is placed on the processing table, the right-angle plate 124 is rotated to rotate around the fixing rod 123, and then the locking bolt 125 is used to lock and fix it, which is convenient for installation and easy for workers to use.

[0039] The above-disclosed embodiments are merely one or more preferred embodiments of this application and should not be construed as limiting the scope of this application. Those skilled in the art can understand that all or part of the processes for implementing the above embodiments and equivalent changes made in accordance with the claims of this application still fall within the scope of this application.

Claims

1. A multi-degree-of-freedom adaptive positioning fixture for machining irregularly shaped mechanical parts, characterized in that, It includes a base, a bottom plate, and a clamping connection assembly. The bottom plate is disposed above the base, and the clamping connection assembly is connected to both the bottom plate and the base. The clamping and connecting assembly includes a cylinder, a push rod, a movable plate, a connecting seat, a ball, a buffer pad, a controller, four sets of reset components, a monitoring component, a leveling adjustment component, and a scanning auxiliary component. The cylinder is detachably connected to the base and is located above the base plate. The push rod is fixedly connected to the cylinder and is located at the output end of the cylinder. The ball is fixedly connected to the push rod and is located at one end of the push rod. The movable plate is disposed on one side of the ball. The connecting seat is fixedly connected to the movable plate and is located on one side of the movable plate, and the connecting seat and the ball are rotatably engaged. The buffer pad is fixedly connected to the movable plate and is located on the other side of the movable plate. The controller is disposed on one side of the base. The monitoring component is connected to the buffer pad. The four sets of reset components are respectively connected to the movable plate and the push rod. The leveling adjustment component is respectively connected to the base and the base plate. The scanning auxiliary component is connected to the base.

2. The multi-degree-of-freedom adaptive positioning fixture for machining irregularly shaped mechanical parts as described in claim 1, characterized in that, The clamping connection assembly further includes a roller seat, which is rotatably connected to the movable plate and located below the movable plate, and the roller seat is in contact with the base plate.

3. The multi-degree-of-freedom adaptive positioning fixture for machining irregularly shaped mechanical parts as described in claim 1, characterized in that, The reset component includes a first fixing ring, a second fixing ring, and a tension spring. The first fixing ring is fixedly connected to the movable plate and is located on one side of the movable plate. The second fixing ring is fixedly connected to the push rod and is located on the outer side wall of the push rod. The two ends of the tension spring are detachably connected to the first fixing ring and the second fixing ring, respectively.

4. The multi-degree-of-freedom adaptive positioning fixture for machining irregularly shaped mechanical parts as described in claim 1, characterized in that, The monitoring component includes a pressure sensor and a displacement sensor. The pressure sensor is disposed on the inner sidewall of the buffer pad, and the displacement sensor is fixedly connected to the moving plate and located below the moving plate. The pressure sensor and the displacement sensor are electrically connected to the controller, respectively.

5. The multi-degree-of-freedom adaptive positioning fixture for machining irregularly shaped mechanical parts as described in claim 4, characterized in that, The horizontal adjustment component includes a support ball rod, a universal joint, and four sets of adjustment components. The support ball rod is fixedly connected to the base and located above the base. The universal joint is fixedly connected to the base plate and located below the base plate. The universal joint and the support ball rod are rotatably engaged. The four sets of adjustment components are respectively connected to the base and the base plate.

6. The multi-degree-of-freedom adaptive positioning fixture for machining irregularly shaped mechanical parts as described in claim 5, characterized in that, The adjusting component includes a base, a hydraulic cylinder, and a top seat. The base is fixedly connected to the base plate and located above the base plate. The top seat is fixedly connected to the bottom plate and located below the bottom plate. The bottom end of the hydraulic cylinder is rotatably connected to the base, and the output end of the hydraulic cylinder is rotatably connected to the top seat.

7. The multi-degree-of-freedom adaptive positioning fixture for machining irregularly shaped mechanical parts as described in claim 6, characterized in that, The scanning auxiliary component includes a bracket and a vision sensor. The bracket is fixedly connected to the base and located above the base. The vision sensor is detachably connected to the bracket and located below the bracket. The vision sensor is electrically connected to the controller.

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