Self-adaptive aligning and clamping device for lead screw workpiece and using method of self-adaptive aligning and clamping device

Abstract

The invention discloses a lead screw workpiece self-adaptive aligning and clamping device and a using method, the device comprises a fixing rack, an automatic aligning mechanism and a self-adaptive clamping mechanism, a center supporting plate and a plurality of supporting cross beams matched with the center supporting plate in a positioning mode are installed on the fixing rack, and linear guide rails in the front-back direction are fixed to the supporting cross beams; the automatic alignment mechanism comprises a rotating arm, a centering rotating shaft, two centering connecting rods and two centering driving plates, the self-adaptive clamping mechanism comprises a transmission air cylinder, an extension spring and chucks, and the clamping centers of the two chucks are located on the axis of the centering rotating shaft. The device can automatically align and clamp a lead screw workpiece at the same time under the combined action of the transmission air cylinder and the extension spring, the clamping force can be adaptively adjusted according to the outer contour of the workpiece, and the device can effectively improve the clamping efficiency and precision of the lead screw workpiece.

Description

Technical Field

[0001] The invention belongs to the technical field of numerical control machining, and relates to a screw workpiece self-adaptive alignment clamping device and a use method thereof. Background Art

[0002] Before using CNC machine tools to process shaft-type workpieces such as lead screws, the workpieces need to be manually aligned, positioned, and clamped. The manual alignment process is cumbersome and the centering accuracy is insufficient, resulting in low quality of part processing. At the same time, special fixtures are only suitable for single size or shape features. When facing multi-specification batch processing needs, it is necessary to frequently replace the jaws, adjust the limit blocks, or replace the fixture as a whole. On the other hand, the clamping force control relies on manual tightening of bolts or hydraulic valves, and the quantitative setting of the clamping force cannot be achieved. In addition, under the influence of multi-source displacement disturbances caused by machining deformation, workpiece tilt, and spindle vibration during the machining process, there is a lack of dynamic compensation capability, which further aggravates the machining error. Summary of the Invention

[0003] In response to the defects in the prior art, the purpose of the present invention is to solve the problem in the prior art that it is difficult to synchronously align, position and clamp workpieces such as shafts and rods during CNC machining, and propose a screw workpiece adaptive alignment and clamping device and a method of use. The present invention can automatically align and clamp workpieces of various diameters, and the clamping force can be adaptively adjusted according to the outer contour of the workpiece. This device can effectively improve the clamping efficiency and accuracy of the workpiece.

[0004] In order to achieve the above technical objectives, the technical solution adopted by the present invention is:

[0005] A screw workpiece adaptive alignment clamping device comprises a fixed platform, an automatic alignment mechanism and an adaptive clamping mechanism, wherein a center support plate and a plurality of support beams positioned and matched with the center support plate are installed on the fixed platform, and a linear guide rail running forward and backward is fixed on the support beam, and the automatic alignment mechanism comprises a rotating arm, a centering rotating shaft, two centering connecting rods and two centering drive plates, a centering rotating shaft is installed at the center hole of the rotating arm, the centering rotating shaft is rotatably installed at the center of the center support plate, the centering drive plates are respectively located in front and behind the centering rotating shaft, the two centering drive plates are arranged in parallel and are both slidably installed on the linear guide rail, one end of a centering connecting rod is rotatably installed on one side of the rotating arm, and the other end is installed on the front center On the driving plate, one end of another centering connecting rod is rotatably mounted on the other side of the rotating arm, and the other end is mounted on the rear centering driving plate. The adaptive clamping mechanism includes a transmission cylinder, a tension spring and a chuck. The transmission cylinder is fixedly mounted on the supporting beam. The cylinder guide rod of the transmission cylinder is connected to a centering driving plate. The transmission cylinder can push the centering driving plate to slide on the linear guide rail in the direction away from the centering rotating axis. The two ends of the tension spring are respectively connected to the centering driving plate and the center support plate. The tension spring can pull the centering driving plate to slide on the linear guide rail in the direction close to the centering rotating axis. The two chucks are respectively mounted on the side of the two centering driving plates facing the centering rotating axis, and the clamping center of the two chucks is located on the axis center line of the centering rotating axis.

[0006] To optimize the above technical solutions, specific measures taken also include:

[0007] There are two transmission cylinders, one on the left and one on the right, which are fixed on the support beams on both sides of the central support plate. The cylinder guide rods of the two transmission cylinders are fixedly connected or hinged to the left and right ends of a centering drive plate through adapters.

[0008] The adaptive clamping mechanism also includes a spring support base and a clamp fixing base. The spring support base is fixed to the left and right sides of the center support plate by bolts, and the clamp fixing base is fixed to the two centering drive plates respectively. One end of the tension spring is fixed to the spring support base, and the other end is fixed to the clamp fixing base. The chuck is fixed to the clamp fixing base.

[0009] The spring support base and the fixture fixing base are both provided with threaded positioning pins with holes, and both ends of the tension spring are respectively fixedly connected to the corresponding threaded positioning pins with holes.

[0010] The chuck includes a chuck mounting base and an arc chuck. The chuck mounting base is fixed to the fixture fixing base by bolts. The chuck mounting base is connected to the arc chuck with screws. There are many types of arc chucks, and the curvature of different types of arc chucks is different. By selecting different types of arc chucks to connect with the chuck mounting base, the curvature of the arc chuck is adapted to the curvature of the outer contour of the screw workpiece.

[0011] A plurality of positioning holes are provided on the fixture fixing base along the left and right directions, and the chuck mounting base is fixedly connected to the fixture fixing base by means of bolts passing through the positioning holes.

[0012] A ball bearing is fixed at the center hole of the center support plate through a bearing base. The bottom end of the centering rotating shaft is installed in the ball bearing, and the top end is fastened to the rotating arm through bolts and nuts.

[0013] A plurality of movable slide blocks are fixed to the lower end surface of the centering drive plate by screws, and the movable slide blocks are slidably mounted on the linear guide rail.

[0014] A cylinder base is fixed on the supporting crossbeam by screws, and a cylinder body of the transmission cylinder is fixed on the cylinder base.

[0015] A method for using a screw workpiece adaptive alignment clamping device, using the screw workpiece adaptive alignment clamping device, includes the following steps:

[0016] Step 1: Select two chucks that match the outer diameter of the screw workpiece, and symmetrically assemble the two chucks in the middle of the side of the two centering drive plates facing the centering rotating shaft, with the clamping centers of the two chucks located on the axis of the centering rotating shaft;

[0017] Step 2: Use a transmission cylinder to push a centering drive plate to slide on the linear guide rail in a direction away from the centering rotation axis. The centering drive plate pushes the rotating arm to rotate around the centering rotation axis through the centering connecting rod, thereby driving another centering connecting rod to pull the other centering drive plate away from the centering rotation axis synchronously. The two chucks move away from each other, and the tension spring is stretched at this time.

[0018] Step 3: Place the screw workpiece on the centering rotating shaft, then the transmission cylinder is depressurized and reset, the tension spring retracts, and the centering drive plate slides on the linear guide rail toward the centering rotating shaft. The two chucks approach each other, clamping the screw workpiece, and applying a slight circumferential swing to the screw workpiece to make the surface of the screw workpiece and the contact surface of the chuck slide relative to each other until a multi-point uniform surface contact state is formed, finally completing the alignment and clamping of the screw workpiece;

[0019] Step 4: When you need to remove the screw workpiece, repeat step 2 and remove the screw workpiece on the centering rotating shaft.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] 1. The present invention adopts the linkage design of the rotating arm, the centering rotary shaft and the centering connecting rod. When the transmission cylinder pushes the centering drive plate on one side, the centering drive plate on the other side moves synchronously in the opposite direction through the connecting rod mechanism, forcing the two chucks to always move symmetrically with the axis of the centering rotary shaft as the reference, eliminating manual centering errors, achieving automatic coincidence of the workpiece axis and the device reference axis, and thus realizing adaptive alignment.

[0022] 2. The elastic reset function of the tension spring of the present invention combined with the contour matching design of the arc chuck enables the clamping force to be dynamically adjusted according to the outer diameter of the workpiece:

[0023] Small diameter workpiece: The spring retraction is small, providing moderate clamping force;

[0024] Large diameter workpiece: The spring stretch increases, the clamping force increases linearly, and the adaptive clamping force function is realized.

[0025] 3. The chuck mounting base of the present invention is adjustably connected to the fixture fixing base through the positioning hole, supporting the rapid replacement of arc chucks of different specifications.

[0026] 4. The transmission cylinder of the present invention adopts a double-cylinder symmetrical layout to provide balanced thrust, ensuring that the centering drive plate slides stably back and forth without tilting or swinging. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is the front view of the present invention.

[0028] Figure 2 It is a three-dimensional structural diagram of the present invention.

[0029] Figure 3 Schematic diagram of the screw clamping of the present invention.

[0030] The figures are marked as follows: 1. Fixed stand, 2. Centering drive plate, 3. Linear guide rail, 4. Centering connecting rod, 5. Fixture fixing base, 6. Chuck mounting base, 7. Arc chuck, 8. Tension spring, 9. Spring support base, 10. Threaded positioning pin with hole, 11. Cylinder base, 12. Transmission cylinder, 13. Cylinder guide rod, 14. Adapter, 15. Center support plate, 16. Ball bearing, 17. Centering rotating shaft, 18. Rotating arm, 19. Moving slider, 20. Screw workpiece. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical solutions and advantages of this application more clearly understood, the present application is described and illustrated below in conjunction with the accompanying drawings and examples. It should be understood that the specific embodiments described herein are merely used to explain this application and are not intended to limit this application. Based on the embodiments provided in this application, all other embodiments obtained by those of ordinary skill in the art without making any creative efforts are within the scope of protection of this application.

[0032] Obviously, the drawings described below are merely examples or embodiments of the present application. Those skilled in the art can, without inventive effort, apply the present application to other similar scenarios based on these drawings. Furthermore, it is also understood that, although the effort involved in such a development process may be complex and lengthy, for those skilled in the art related to the content disclosed in this application, changes in design, manufacturing, or production based on the technical content disclosed in this application are merely conventional technical means and should not be construed as an insufficiency of the content disclosed in this application.

[0033] References to "embodiments" in this application mean that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it refer to independent or alternative embodiments that are mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described in this application may be combined with other embodiments unless there is a conflict.

[0034] like Figures 1 to 3 The self-adaptive alignment and clamping device for a screw workpiece shown comprises a fixed stand 1, an automatic alignment mechanism and a self-adaptive clamping mechanism.

[0035] A central support plate 15 and several supporting beams are mounted on the upper end surface of the fixed gantry 1. Several linear guide rails 3 are bolted to the ends of the central beam. An automatic alignment mechanism is mounted on the central support plate 15 and includes a rotating arm 18, a centering rotating shaft 17, a centering connecting rod 4, and a centering drive plate 2. The centering rotating shaft 17 is mounted in the center hole of the rotating arm 18. One end of the two centering connecting rods 4 is rotatably mounted in the through holes on both sides of the rotating arm 18 via bolts and nuts, and the other end is rotatably mounted on the centering drive plate 2. The adaptive clamping mechanism includes a transmission cylinder 12, a spring support base 9, a tension spring 8, and a fixture fixing base 5. The transmission cylinder 12 is mounted on the supporting beams on both sides of the fixed gantry 1. The front end of the cylinder guide rod 13 is connected to the centering drive plate 2 via an adapter 14. The spring support base 9 is bolted to both sides of the central support plate 15. The tension spring 8 is mounted on the support base 9 and connected to the fixture fixing base 5 via a threaded, holed locating pin 10.

[0036] In order to realize the rotational movement of the rotating arm 18, the central support plate 15 is installed on the support platform. A ball bearing 16 is fixed at the center hole of the central support plate 15 through a bearing base. The bottom end of the centering rotating shaft 17 is installed in the above-mentioned ball bearing 16, and the top end is tightly connected to the rotating arm 18 through bolts and nuts. The mounting holes on both sides of the rotating arm 18 are symmetrical with each other with the centering rotating shaft 17 as the center.

[0037] In order to further realize the conversion of the rotational motion of the above-mentioned rotating arm 18 into the linear motion of the centering drive plate 2, the mounting holes on both sides of the rotating arm 18 are rotatably connected with the centering link 4, and the other end of the centering link 4 is rotatably connected to the centering drive plate 2. The lower end surface of the centering drive plate 2 is fixed with a number of movable sliders 19 by screws. The movable sliders 19 cooperate with the linear guide rails 3 fixed on the middle supporting beam. The rotational motion of the above-mentioned rotating arm 18 can be transmitted to the centering drive plates 2 on both sides through the centering link 4, and converted into the opposite and opposite motions of the centering drive plates 2 along the linear guide rails 3.

[0038] In order to achieve the back-to-back synchronous movement of the two centering drive plates 2, cylinder bases 11 are fixed to the supporting beams on both sides of the fixed platform 1 with screws. The end of the transmission cylinder 12 in the clamping device is fixed on the cylinder base 11, and the front end of the cylinder's transmission guide rod 13 is firmly connected to the centering drive plate 2 through the adapter 14.

[0039] In order to further realize the synchronous movement of the two centering drive plates 2 toward each other, several clamp fixing bases 5 are installed on the centering drive plate 2. A threaded hole is opened at the lower part of the clamp fixing base 5, and a matching threaded hole positioning pin 10 is installed in the threaded hole. Several spring support bases 9 are installed on both sides of the center support plate 15. A threaded hole is opened on the spring support base 9, and a threaded hole positioning pin 10 is also installed in the threaded hole, which is coaxial with the threaded hole at the lower part of the clamp fixing base 5. The two ends of the tension spring 8 are respectively connected to the threaded hole positioning pins 10 installed on the above-mentioned clamp fixing base 5 and the spring support base 9.

[0040] In order to realize the adaptive alignment, clamping and expansion action of the arc chuck 7, a plurality of positioning holes are opened on the upper part of the clamp fixing base 5, and a plurality of chuck mounting bases 6 are fixed at the positioning holes with bolts. The front end of the chuck mounting base 6 is connected with arc chucks 7 of different models with screws. All the arc chucks 7 in the device can realize synchronous alignment, clamping and expansion action under the thrust of the transmission cylinder 12 and the tension of the tension spring 8.

[0041] During actual use of the present invention, the transmission cylinder 12 located on the supporting beams on both sides of the fixed platform 1 first drives the cylinder guide rod 13 to extend, pushing the centering drive plate 2 connected thereto to move along the linear guide rail 3. The centering drive plate 2 pulls the rotating arm 18 to rotate around the axis through the centering link 4. Then the rotational force of the above-mentioned rotating arm 18 is converted into the linear motion of another centering drive plate 2 through the centering link 4, and can realize the synchronous back-to-back movement of the two centering drive plates 2 under the design of the centering structure, and then can drive the clamp fixed base 5 installed on the centering drive plate 2 to move outward synchronously with the centering rotating axis 17 as the center. At this time, when the device starts to position and clamp the screw workpiece 20, the transmission cylinder 12 is pneumatically reset, and its cylinder guide rod 13 loses thrust. The two centering drive plates 2 will move toward each other along the linear guide rail 3 under the tension of the tension spring 8, and can achieve synchronous centering movement under the joint action of the centering rotating arm 18 and the centering connecting rod 4, thereby driving the fixture fixed base 5 fixed on the centering drive plate 2 to perform synchronous centering movement. At this time, a pair of arc chucks 7 installed on the above-mentioned fixture fixed base 5 also retract with the centering rotating arm 18 as the center until the arc chucks 7 are tightly fitted with the screw workpiece 20 to be measured, and finally the alignment and clamping operation is completed. The present invention has an ingenious structure. Under the joint action of the transmission cylinder 12 and the tension spring 8, the screw workpiece 20 can be automatically aligned and clamped at the same time, and the clamping force can be adaptively adjusted according to the outer contour of the screw workpiece 20. The present device can effectively improve the clamping efficiency and accuracy of the workpiece.

[0042] The present invention also provides a method for using a screw workpiece adaptive alignment clamping device, comprising the following steps:

[0043] S1. Base positioning and installation: Fix the center support plate 15 to the preset installation position of the workbench, and ensure that the axis of the centering rotation shaft 17 is coaxial with the theoretical clamping axis of the screw workpiece 20 through the calibration fixture;

[0044] S2. Collet matching adjustment: Select a circular arc collet 7 that matches the outer diameter of the workpiece, symmetrically assemble the collet mounting base 6 in the center area of ​​the fixture fixed base 5, and use positioning pins to ensure that the center of curvature of each circular arc collet 7 coincides with the axis of the centering rotation shaft 17;

[0045] S3. Adaptive clamping operation: The bilateral centering drive plates 2 are driven to move in opposite directions by the transmission cylinder 12, and the centering drive plates 2 slide along the linear guide rails 3 through the movable slider 19 at the bottom thereof, and the screw workpiece 20 is placed directly above the centering rotating shaft 17 between the two chucks to complete the initial alignment; then the external driving force is removed, and the stretched tension spring 8 drives the alignment component to produce adaptive displacement through the release of elastic potential energy, thereby realizing a flexible clamping action on the screw workpiece 20; in this process, a controllable circumferential micro-swing is applied to the workpiece by hand, causing the surface of the screw workpiece 20 and the contact surface of each arc chuck 7 to slide relative to each other until a multi-point uniform surface contact state is formed, and finally completing the composite action of high-precision automatic alignment and adaptive rigid clamping.

[0046] S4, workpiece unloading: Perform a synchronous reverse pulling operation on the double-sided chuck mounting base 6 to directly remove the clamped lead screw workpiece 20.

[0047] The above embodiments are preferred implementations of the present invention, but the implementation of the present invention is not limited to the described embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be considered equivalent replacement methods and are included in the scope of protection of the present invention.

Claims

1. A screw workpiece adaptive alignment clamping device, characterized by: The invention comprises a fixed platform (1), an automatic alignment mechanism and an adaptive clamping mechanism. The fixed platform (1) is provided with a central support plate (15) and a plurality of support beams positioned and matched with the central support plate (15). A linear guide rail (3) running forward and backward is fixed on the support beam. The automatic alignment mechanism comprises a rotating arm (18), a centering rotating shaft (17), two centering connecting rods (4) and two centering drive plates (2). The center hole of the rotating arm (18) is provided with a centering rotating shaft (17). The centering rotating shaft (17) is rotatably mounted at the center of the central support plate (15). The centering drive plates (2) are respectively located in front of and behind the centering rotating shaft (17). The two centering drive plates (2) are arranged in parallel and are both slidably mounted on the linear guide rail (3). One end of a centering connecting rod (4) is rotatably mounted on one side of the rotating arm (18), and the other end is mounted on the previous centering drive plate (2). The other centering connecting rod (4) is rotatably mounted on the center hole of the rotating arm (18). One end is rotatably mounted on the other side of the rotating arm (18), and the other end is mounted on the rear centering drive plate (2). The adaptive clamping mechanism includes a transmission cylinder (12), a tension spring (8) and a chuck. The transmission cylinder (12) is fixedly mounted on the supporting beam. The cylinder guide rod (13) of the transmission cylinder (12) is connected to a centering drive plate (2). The transmission cylinder (12) can push the centering drive plate (2) to slide on the linear guide rail (3) in a direction away from the centering rotation axis (17). The two ends of the tension spring (8) are respectively connected to the centering drive plate (2) and the center support plate (15). The tension spring (8) can pull the centering drive plate (2) to slide on the linear guide rail (3) in a direction close to the centering rotation axis (17). The two chucks are respectively mounted on one side of the two centering drive plates (2) facing the centering rotation axis (17). The clamping centers of the two chucks are located on the axis center line of the centering rotation axis (17).

2. The screw workpiece adaptive alignment clamping device according to claim 1, characterized in that: There are two transmission cylinders (12), one on the left and one on the right, which are fixed on the support beams on both sides of the central support plate (15). The cylinder guide rods (13) of the two transmission cylinders (12) are fixedly connected or hinged to the left and right ends of a centering drive plate (2) through adapters (14).

3. The screw workpiece adaptive alignment clamping device according to claim 2, characterized in that: The adaptive clamping mechanism further comprises a spring support base (9) and a clamp fixing base (5), wherein the spring support base (9) is fixed to the left and right sides of the central support plate (15) by bolts, and the clamp fixing base (5) is respectively fixed to the two centering drive plates (2), one end of the tension spring (8) is fixed to the spring support base (9), and the other end is fixed to the clamp fixing base (5), and the clamp is fixed to the clamp fixing base (5).

4. The screw workpiece adaptive alignment clamping device according to claim 3, characterized in that: The spring support base (9) and the clamp fixing base (5) are both provided with threaded positioning pins with holes (10), and the two ends of the tension spring (8) are respectively fixedly connected to the corresponding threaded positioning pins with holes (10).

5. The screw workpiece adaptive alignment clamping device according to claim 1, characterized in that: The chuck comprises a chuck mounting base (6) and an arc chuck (7). The chuck mounting base (6) is fixed to the fixture fixing base (5) by bolts. The chuck mounting base (6) is connected to the arc chuck (7) by screws. There are many types of arc chucks (7). Different types of arc chucks (7) have different curvatures. By selecting different types of arc chucks (7) to connect with the chuck mounting base (6), the curvature of the arc chuck (7) is adapted to the curvature of the outer contour of the screw workpiece (20).

6. The screw workpiece adaptive alignment clamping device according to claim 5, characterized in that: The clamp fixing base (5) is provided with a plurality of positioning holes along the left and right directions, and the clamp mounting base (6) is fixedly connected to the clamp fixing base (5) by means of bolts passing through the positioning holes.

7. The screw workpiece adaptive alignment clamping device according to claim 1, characterized in that: A ball bearing (16) is fixed to the center hole of the center support plate (15) through a bearing base, the bottom end of the centering rotating shaft (17) is installed in the ball bearing (16), and the top end is fastened to the rotating arm (18) through bolts and nuts.

8. The screw workpiece adaptive alignment clamping device according to claim 1, characterized in that: A plurality of movable slide blocks (19) are fixed to the lower end surface of the centering drive plate (2) by screws, and the movable slide blocks (19) are slidably mounted on the linear guide rail (3).

9. The screw workpiece adaptive alignment clamping device according to claim 1, characterized in that: A cylinder base (11) is fixed on the supporting crossbeam by screws, and a cylinder body of the transmission cylinder (12) is fixed on the cylinder base (11).

10. A method for using a screw workpiece adaptive alignment clamping device, using the screw workpiece adaptive alignment clamping device according to any one of claims 1 to 9, characterized in that: The steps include: Step 1: Select two chucks that match the outer diameter of the screw workpiece (20), and symmetrically assemble the two chucks at the middle position of one side of the two centering drive plates (2) facing the centering rotating shaft (17), with the clamping centers of the two chucks located on the axis of the centering rotating shaft (17); Step 2: Push a centering drive plate (2) on the linear guide rail (3) to slide away from the centering rotation axis (17) through the transmission cylinder (12). The centering drive plate pushes the rotating arm (18) to rotate around the centering rotation axis (17) through the centering connecting rod (4), thereby driving another centering connecting rod (4) to pull the other centering drive plate (2) away from the centering rotation axis (17) synchronously. The two chucks move away from each other, and at this time, the tension spring (8) is stretched. Step 3: Place the screw workpiece (20) on the centering rotating shaft (17), then the transmission cylinder (12) is depressurized and reset, the tension spring (8) is retracted, and the centering drive plate (2) is pulled to slide on the linear guide rail (3) toward the centering rotating shaft (17), the two chucks are close to each other, clamping the screw workpiece (20), applying a circumferential slight swing to the screw workpiece (20), so that the surface of the screw workpiece (20) and the contact surface of the chuck slide relative to each other until a multi-point uniform surface contact state is formed, and finally the alignment and clamping of the screw workpiece (20) are completed; Step 4: When the screw workpiece (20) needs to be removed, repeat step 2 to remove the screw workpiece (20) on the centering rotating shaft (17).

Images