A clamping method and device suitable for complex trajectory motion

Abstract

The present invention discloses a clamping method and device suitable for complex trajectory motion. The clamping mechanism uses a purely mechanical method to achieve complex trajectory motion of the clamped material. The clamping mechanism includes a guide rail for guiding the mechanism to perform complex trajectory motion, an upper roller and a lower roller used in pairs, a propulsion cylinder and a push-pull rod for transmitting motion, a support frame for carrying all parts and components, a clamping head assembly for clamping the material, and a travel switch for controlling stopping or reversing during motion. The guide rail is a non-linear guide rail or a circular arc guide rail, or a simple combination of a non-linear guide rail and a circular arc guide rail, and has complex trajectory characteristics. The concave arc surface of the upper roller rolls on the convex arc surface of the guide rail, and the cylindrical surface of the lower roller rolls on the plane of the guide rail. The push-pull rod is connected to the piston rod of the propulsion cylinder, and the propulsion cylinder swings around a swing pin shaft as the center. The clamping jaws in the clamping head assembly open and clamp the clamped material under the meshing motion of the double-toothed gear rod and the fan-shaped gear block.

Description

Technical Field

[0001] The present invention belongs to the field of mechanical automation control, and in particular relates to a clamping method and device suitable for complex trajectory motion. Background Art

[0002] In the automated manufacturing process, robots are often used to transfer materials between workbenches and to load and unload materials. Robots achieve material transfer and loading and unloading through linear motion, rotation, or a combination of these two motions.

[0003] When the material clamped by the robot needs to perform complex trajectory movement, simple motion combinations cannot meet the requirements. For example, for automatic welding of complex curves, a six-degree-of-freedom robot is often used, and automatic welding of complex curves is achieved through programming operations. However, the hardware cost of multi-degree-of-freedom robots and their corresponding control systems is relatively high, and the software programming is technically difficult.

[0004] At the same time, due to the complex mechanical structure and the large number of sensor devices, it cannot work effectively for a long time under harsh working conditions. The sensor equipment and bearing equipment have been damaged, and the maintenance cost is high. Summary of the Invention

[0005] Technical problem to be solved by the present invention: The purpose of the present invention is to solve the deficiencies in the prior art and to provide a clamping device which has a simple structure and is applicable to harsh working conditions and is suitable for complex trajectory motion.

[0006] The technical solution of the present invention: The present invention provides a clamping method suitable for complex trajectory motion, selects the optimal path for material transportation, plans a non-linear guide rail matching the optimal path for material transportation in a two-dimensional plane, and arranges a clamping mechanism on the non-linear guide rail that can reciprocate along the non-linear guide rail; after the clamping mechanism clamps the material, it moves along the non-linear guide rail to complete the material transportation.

[0007] The present invention also discloses a clamping device suitable for complex trajectory motion, comprising the above-mentioned non-linear guide rail, on which a clamping mechanism that can move along the guide rail is provided; the clamping mechanism reciprocates along the guide rail through a driving mechanism.

[0008] Furthermore, the driving mechanism includes a propulsion lever; the propulsion lever is hinged to a fixed support; the piston rod of the propulsion lever is hinged to one end of a push-pull rod; the other end of the push-pull rod is hinged to the clamping mechanism;

[0009] The clamping mechanism includes a support frame and a clamping assembly arranged at the lower end of the support frame; the support frame is provided with an upper roller located at the upper end of the guide rail and a lower roller arranged at the lower end of the guide rail;

[0010] The upper end surface of the guide rail is provided with a flange; the end surface of the upper roller is provided with a concave arc surface matching the flange;

[0011] The clamping mechanism is provided with a clamping cylinder at the lower end, and a double-toothed gear rod is provided at the end of the clamping cylinder piston rod of the clamping cylinder; sector-shaped gear blocks are provided along both sides of the tooth surface of the double-toothed gear rod; the sector-shaped gear blocks are connected to the clamping claws;

[0012] When the clamping cylinder is in a normal state, that is, when the piston rod of the clamping cylinder is in its original position, the double-toothed gear rod is in its original position, and the two symmetrical clamping jaws are closest to each other and are in a clamping state;

[0013] When the piston rod of the clamping cylinder is extended, the double-toothed gear rod is extended, driving the sector-shaped gear block to rotate around the pin shaft, the distance between the two clamping jaws increases, and the clamping jaws are in an open state.

[0014] Furthermore, the propulsion bar is arranged on a swing bracket, and the end of the swing bracket is hinged to the fixed support.

[0015] Furthermore, the concave arc radius of the upper roller end surface is greater than the flange radius of the upper end surface of the guide rail; the inner hole of the upper roller is movably matched with the upper roller shaft;

[0016] The lower roller is a cylinder with an inner hole, the outer cylindrical surface of the lower roller contacts the lower end surface of the guide rail, and the cylindrical inner hole of the lower roller is movably matched with the lower roller shaft;

[0017] Under the action of the push-pull rod, the upper roller and the lower roller roll along the guide rail.

[0018] Furthermore, the two sector-shaped tooth blocks are symmetrically distributed about the axis of the double-toothed gear rod and are fixedly connected to the clamping claw; during the extension and retraction of the double-toothed gear rod, the drive

[0019] Furthermore, the clamping cylinder is arranged in the support frame and fixed on the lower base plate of the support frame. The clamping cylinder piston rod passes through the support frame and is connected to the double-toothed gear rod.

[0020] Furthermore, the sector-shaped tooth blocks are symmetrically mounted on the clamping jaw support block; and a clamping spring is provided between the two clamping jaws.

[0021] Beneficial effects:

[0022] The beneficial effects of the present invention compared with the prior art are as follows:

[0023] 1. The present invention directly adopts a guide rail with a non-linear, two-dimensional planar complex trajectory that matches the material path planning. The clamping mechanism is installed on the guide rail, and completes the movement of the planar complex trajectory under the external force of the push-pull rod and the swingable propulsion cylinder; the present invention uses a purely mechanical method to realize the complex trajectory movement of the clamping mechanism on the plane. Compared with existing equipment, the cost is lower and the load-bearing capacity is better. At the same time, it has a simple structure, high reliability, low cost and low technical difficulty.

[0024] 2. The front and rear ends of the propulsion bar are hinged to the push-pull rod and the fixed support respectively. At the same time, the push-pull rod is hinged to the clamping mechanism. The three-stage hinge ensures that the propulsion bar can drive the push-pull rod and drive the clamping mechanism to move forward or backward at any position of the guide rail. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 Schematic diagram of the overall structure of the clamping device in the present invention;

[0026] Figure 2 Schematic diagram of the motion state of the clamping device in the present invention;

[0027] Figure 3 for Figure 1 Schematic cross-section of the middle AA;

[0028] Figure 4 for Figure 1 Schematic cross-section of the BB.

[0029] Reference numerals: 101-push-pull rod, 102-advance cylinder, 103-swing bracket, 104-swing pin, 105-sliding bearing, 106-advance cylinder piston rod, 107-fixed support, 108-pin nut, 109-cylinder fixing screw, 201-guide rail, 202-travel switch, 301-washer, 302-upper roller, 303-upper roller shaft, 304-lower roller, 305- Lower roller shaft, 306-support frame, 307-clamping cylinder, 308-clamping cylinder piston rod, 309-sector gear block, 310-double-toothed gear rod, 311-clamping spring, 312-clamping jaw, 313-gasket, 314-nut, 315-fixing screw, 316-cylinder fastening screw, 401-pin shaft, 402-clamping jaw support block, 403-clamping material, 404-pin shaft fastening screw. DETAILED DESCRIPTION

[0030] In order to deepen the understanding of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings. The embodiments are only used to explain the present invention and do not constitute a limitation on the scope of protection of the present invention.

[0031] like Figure 1-4As shown, one end of the push-pull rod 101 is connected to the support frame 306 through a fixing screw 315, and the other end is threadedly connected to the piston rod 106 of the propulsion cylinder and tightened with a nut. After the propulsion cylinder 102 is connected to high-pressure air, it drives the piston rod 106 to move back and forth, and at the same time drives the push-pull rod 101 and the support frame 306 to complete the movement of a complex trajectory on the guide rail 201.

[0032] On the opposite side of the piston rod 106, the thrust cylinder 102 is equipped with a swing bracket 103 through a cylinder fixing screw 109. An inner hole is machined on the swing bracket 103, and a sliding bearing 105 is installed in the inner hole with an interference fit. The sliding bearing 105 is assembled with the swing pin 104 in a dynamic fit. The swing pin 104 passes through the swing bracket 103 and the fixed support 107 and is tightly connected with a pin nut 108. When the clamping mechanism is in motion, the thrust cylinder 102 is subjected to the reaction force of the push-pull rod 101 and swings around the swing pin 104.

[0033] Combine Figure 2 As can be seen, guide rail 201 is a non-linear guide rail designed based on the material path planning. In the present invention, the material path, non-linear guide rails, or non-circular guide rails, are not simply a combination of linear and circular guide rails. Instead, they are designed based on the complex motion trajectory of the clamped material. Guide rail 201 is machined from a casting or welded from multiple steel sections. Guide rail 201 is fixedly mounted on the equipment's work surface or can be fixed to the ground using a bracket. Its working height can be adjusted using the guide rail bracket.

[0034] The limit switch 202 is installed and fixed at the starting position, midway working point and end position of the clamping mechanism to control the pause and reversal of the clamping mechanism during complex trajectory movement. The limit switch 202 adopts mechanical contact or photoelectric non-contact type. When a mechanical limit switch is used, the clamping mechanism is installed with a bump block. When the limit switch 202 contacts the bump block, a signal is sent to control the gas distribution system to reverse.

[0035] Combine Figure 3 It can be seen that the support frame 306 is the skeleton of the clamping mechanism, and its appearance is [-shaped. The upper plane is connected to the push-pull rod 101 with a fixing screw 315; the upper roller 302, the upper roller shaft 303, the lower roller 304, and the lower roller shaft 305 are installed and fixed on the middle vertical surface, and are fixed to the support frame 306 through the gasket 313 and the nut 314; the clamping cylinder 307 is installed on the lower plane, and the clamping claw support block 402 is installed on the other side.

[0036] The upper surface of the guide rail 201 is processed into a convex semi-arc surface and contacts the surface of the upper roller 302. The radius of the convex arc is smaller than the radius of the concave arc surface of the upper roller 302. The lower surface of the guide rail is processed into a plane and contacts the cylindrical surface of the lower roller 304.

[0037] The guide rail 201 is clamped up and down by the upper roller 302 and the lower roller 304 to ensure that the clamping mechanism can reciprocate on the guide rail 201 .

[0038] A pair of upper rollers 302 are symmetrically mounted on support frame 306. The outer surface of the upper rollers 302 is a concave arc, ensuring contact with the upper rail surface of guide rail 201 during installation. The radius of the concave arc of the upper rollers 302 is larger than the radius of the convex arc of the upper rail surface. The upper roller shaft 303 is inserted through the inner hole. Under the external force of the push-pull rod 101, the upper rollers 302 roll on the upper rail surface of guide rail 201.

[0039] A pair of lower rollers 304 are symmetrically mounted on a support frame 306. The lower rollers 304 are cylindrical in shape, and when installed, their outer cylindrical surfaces maintain contact with the lower rail surface of the guide rail 201. Lower roller shafts 305 are inserted through the inner bores of the lower rollers 304 and are in a flexible fit. Under the external force of the push-pull rod 101, the lower rollers 304 roll on the lower rail surface of the guide rail 201.

[0040] The clamping cylinder 307 is fixedly mounted on the lower plane of the support frame 306 by the cylinder fastening screw 316. The clamping cylinder piston rod 308 and the double-toothed gear rod 310 are connected to each other by threads. When the clamping cylinder 307 is connected to high-pressure air, the piston rod 308 is driven and the double-toothed gear rod 310 is driven to reciprocate.

[0041] A pair of sector-shaped tooth blocks 309 are symmetrically mounted on the jaw support block 402. The sector-shaped tooth blocks 309 and the double-flank gear rod 310 mesh together to form a gear rack with the same module. The reciprocating motion of the double-flank gear rod 310 drives the sector-shaped tooth blocks 309. A clamping jaw 312 is fixedly mounted on each sector-shaped tooth block 309. The clamping jaw 312 opens and closes around the clamping jaw pin 401 under the meshing motion of the sector-shaped tooth block 309 and the double-flank gear rod 310.

[0042] A clamping spring 311 is installed on a pair of clamping jaws 312 to ensure that the meshing surfaces of the double-toothed gear rod 310 and the sector-shaped gear block 309 have good contact. When the clamping jaws 312 are opened, they overcome the clamping spring force and maintain moderate clamping force when closed.

[0043] Combine Figure 4 As can be seen, a pair of sector-shaped tooth blocks 309 are assembled with the jaw support block 402 via the jaw pins 401. The jaw pins 401 are a pair, each secured with two pin-tightening screws 404 to prevent axial movement and circumferential rotation. Driven by the meshing engagement between the sector-shaped tooth blocks 309 and the double-toothed gear rod 310, the jaws 312 rotate around the jaw pins 401 to open and clamp the material 403.

[0044] The basic principles, main features, and advantages of the present invention are shown and described above. Those skilled in the art should understand that the present invention is not limited to the specific embodiments described above. The specific embodiments and descriptions in the specification are merely intended to further illustrate the principles of the present invention. Various changes and modifications may be made to the present invention without departing from the spirit and scope of the present invention. Such changes and modifications are intended to fall within the scope of the present invention. The scope of the present invention is defined by the claims and their equivalents.

Claims

1. A clamping method suitable for complex trajectory motion, characterized by: An optimal material transport path is selected, a non-linear guide rail is planned in a two-dimensional plane to match the optimal material transport path, and a clamping mechanism is provided on the non-linear guide rail that can reciprocate along the non-linear guide rail; after the clamping mechanism clamps the material, it moves along the non-linear guide rail to complete the material transport; The clamping mechanism reciprocates along the guide rail through a driving mechanism; the driving mechanism includes a propulsion lever (102); the propulsion lever (102) is hinged to a fixed support (107); a piston rod (106) of the propulsion lever (102) is hinged to one end of a push-pull rod (101); the other end of the push-pull rod (101) is hinged to the clamping mechanism; The clamping mechanism comprises a support frame (306) and a clamping assembly arranged at the lower end of the support frame (306); an upper roller (302) located at the upper end of the guide rail (201) and a lower roller (304) arranged at the lower end of the guide rail (201) are provided in the support frame (306); The upper end surface of the guide rail (201) is provided with a flange; the end surface of the upper roller (302) is provided with a concave arc surface matching the flange; The clamping mechanism has a clamping cylinder (307) at the lower end thereof, and a double-toothed gear rod (310) is provided at the end of the clamping cylinder piston rod (308) of the clamping cylinder (307); sector-shaped gear blocks (309) are provided along both sides of the tooth surface of the double-toothed gear rod (310); and the sector-shaped gear blocks (309) are connected to the clamping claw (312). When the clamping cylinder (307) is in a normal state, that is, the clamping cylinder piston rod (308) is in its original position, the double-toothed gear rod (310) is in its original position, and the two symmetrical clamping jaws (312) are closest to each other and are in a clamping state; When the clamping cylinder piston rod (308) is extended, the double-toothed gear rod (310) is extended, driving the sector-shaped gear block (309) to rotate around the pin shaft (401), and the distance between the two clamping jaws (312) increases, and the clamping jaws (312) are in an open state; The concave arc radius of the end surface of the upper roller (302) is greater than the flange radius of the upper end surface of the guide rail (201); the inner hole of the upper roller (302) is in dynamic cooperation with the upper roller shaft (303); The lower roller (304) is a cylinder with an inner hole, the outer cylindrical surface of the lower roller (304) contacts the lower end surface of the guide rail (201), and the cylindrical inner hole of the lower roller (304) is in dynamic cooperation with the lower roller shaft (305); Under the action of the push-pull rod (101), the upper roller (302) and the lower roller roll along the guide rail (201).

2. The clamping method suitable for complex trajectory motion according to claim 1, characterized in that: The propulsion lever (102) is arranged on a swing bracket (103), and the end of the swing bracket (103) is hinged to the fixed support (107).

3. The clamping method suitable for complex trajectory motion according to claim 1, characterized in that: The two sector-shaped tooth blocks (309) are symmetrically distributed about the axis of the double-toothed gear rod (310) and are fixedly connected to the clamping claw (312).

4. The clamping method suitable for complex trajectory motion according to claim 3, characterized in that: The clamping cylinder (307) is arranged in the support frame (306) and fixed on the lower base plate of the support frame (306); the clamping cylinder piston rod (308) passes through the support frame (306) and is connected to the double-toothed gear rod (310).

5. The clamping method suitable for complex trajectory motion according to claim 3, characterized in that: The sector-shaped tooth block (309) is symmetrically mounted on the clamping jaw support block (402); a clamping spring (311) is provided between the two clamping jaws (312).

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