Chuck mechanism

Abstract

A chuck mechanism enables downsizing of the device with a simple structure, has a wide open/close width of clamps, and hardly causes a dent or scar on pipes. The chuck mechanism includes a horizontally arranged shaft, a frame, a pair of dog leg shaped link members, parallel link members, a pair of clamp members, and a swing drive mechanism.

Claims

1. A system comprising: a chuck mechanism and a swivel drive mechanism; the chuck mechanism comprising: a horizontally arranged shaft; a frame provided at a distal end of the shaft and extending transversely to a longitudinal axis of the shaft, the frame inducting opposing ends provided on opposite sides of the longitudinal axis of the shaft; a pair of link members each having a bent portion protruding inwardly toward the longitudinal axis of the shaft and being swingably supported at the bent portions respectively on opposite sides of the frame, and each of the link members having a front part and a rear part extending from the bent portion; parallel link members each having a rear end rotatably supported on the opposite sides of the frame and each extending parallel to one of the front parts of the pair of link members; a pair of clamp members having clamp surfaces arranged opposite each other, each clamp member being rotatably supported at a distal end of one of the link members and at a distal end of one of the parallel link members; the swing drive mechanism configured to swing the rear parts of the pair of link members in directions where the rear parts move apart from and closer to each other, wherein the swing drive mechanism comprises a cylindrical member fitted on and sliding along an outer surface of the shaft in the longitudinal axis of the shaft and having connecting link members extending outwardly, short link members extending between and rotatably coupled to respective rear ends of the pair of link members and to the connecting link members, and an electric cylinder configured to slide the cylindrical member along the shaft, and a swing rod having a lower end, an upper end and a midpoint; the electric cylinder includes a rod that drives lineally a the lower end of the swing rod having the upper end rotatably supported at the midpoint, swing motion of the swing rod is received by a flange provided on an outer periphery of the cylindrical member so that the cylindrical member slides along the shaft.

2. The system according to claim 1, wherein the clamp surfaces of the pair of clamp members are formed as V-shaped grooves.

3. The system according to claim 1, wherein start-up, stop, forward rotation, reverse rotation, and torque of the electric cylinder are controlled by control means.

4. The system according to claim 1, wherein the system is provided with a rotary drive mechanism rotating the chuck mechanism around the longitudinal axis of the shaft.

5. The system according to claim 1, wherein the system is provided with a transfer drive mechanism causing the chuck mechanism to move along an axial direction of the shaft.

6. The system according to claim 1, wherein the system is provided with a swivel drive mechanism swiveling the chuck mechanism around a vertical axis.

Description

BRIEF DESCRIPTION OF DRAWINGS

(1) FIG. 1 is a conceptual diagram of major parts of one embodiment of chuck mechanism according to the present invention, or a side view illustrating a state in which the chuck mechanism is open.

(2) FIG. 2 is a conceptual diagram of major parts of one embodiment of chuck mechanism according to the present invention, or a side view illustrating a state in which the chuck mechanism is closed.

(3) FIG. 3 is a conceptual diagram of major parts of one embodiment of chuck mechanism according to the present invention, or a front view illustrating a state in which a large-diameter pipe is clamped.

(4) FIG. 4 is a conceptual diagram of major parts of one embodiment of chuck mechanism according to the present invention, or a front view illustrating a state in which a small-diameter pipe is clamped.

(5) FIG. 5 is a perspective view illustrating one embodiment of chuck mechanism according to the present invention in its entirety.

(6) FIG. 6 is a backside view illustrating one embodiment of chuck mechanism according to the present invention in its entirety.

(7) FIG. 7 is an exploded perspective view illustrating a swivel drive mechanism in one embodiment of chuck mechanism according to the present invention.

DESCRIPTION OF EMBODIMENT

(8) Hereinafter, one embodiment of chuck mechanism according to the present invention will be described in detail with reference to the drawings.

(9) FIG. 1 and FIG. 2 are conceptual diagrams illustrating major parts of one embodiment of chuck mechanism according to the present invention. FIG. 1 and FIG. 2 are side views, respectively illustrating a state in which the chuck mechanism is open, and a state in which the chuck mechanism is closed.

(10) In these drawings, reference numeral 1 denotes a shaft that is arranged horizontally, and 2 denotes a frame provided at a distal end of the shaft 1 and protruding in the up and down direction of the shaft 1. To an upper part 2a and a lower part 2b of the frame 2, are provided, respectively, a pair of dog leg shaped link members 3 and 4 having bent portions 3a and 4a protruded inward and swingably supported at the respective bent portions 3a and 4a, and at parallel link members 5 and 6 having respectively rear ends 5a and 6a rotatably supported on the frame 2 so as to be parallel to front parts of the pair of dog leg shaped link members 3 and 4, respectively.

(11) A pair of clamp members 7 and 8, arranged to have clamp surfaces 7a and 8a facing each other, are rotatably supported respectively at the distal end 3b of the dog leg shaped link member 3 on the upper part 2a of the frame 2 and the distal end 5b of the parallel link member 5 disposed parallel to the link member 3, and the distal end 4b of the dog leg shaped link member 4 on the lower part 2b of the frame 2 and the distal end 6b of the parallel link member 6 disposed parallel to the link member 4. The clamp surfaces 7a and 8a are formed as V-shaped grooves, as shown in FIG. 3 or FIG. 4.

(12) Short link members 9 and 10 are rotatably supported at rear ends 3c and 4c of the pair of dog leg shaped link members 3 and 4, respectively. A connecting link member 11 is rotatably coupled to the short link members 9 and 10 to connect them. A cylindrical member 12 fitted on the shaft 1 and slides along the shaft 1 is fixedly attached to a central portion 11a of the connecting link member 11. An electric cylinder 13 is provided for causing the cylindrical member 12 to slide along the shaft 1.

(13) The electric cylinder 13 includes a rod 13a that provides linear drive by rotation of a ball screw with the use of a stepping motor. The rod 13a causes a swing rod 14 having an upper end 14a rotatably supported at a fixed point to swing, and the swing motion of the swing rod 14 is received by a flange 12a provided on an outer periphery of the cylindrical member 12 so that the cylindrical member 12 slides along the shaft 1. Start-up, stop, forward rotation, reverse rotation, rotation speed, torque, etc. of the stepping motor that constitutes the electric cylinder 13 are controlled by way of control means (not shown), based on detection of pulses generated in accordance with the rpm with the use of an encoder and the like.

(14) In the present invention, the short link members 9 and 10 rotatably supported respectively on the rear ends 3c and 4c of the pair of dog leg shaped link members 3 and 4, the connecting link member 11 connecting the short link members 9 and 10, the cylindrical member 12 provided to the connecting link member 11 and fitted on the shaft 1 to slide along the shaft 1, and the electric cylinder 13 for causing the cylindrical member 12 to slide along the shaft, may sometimes be referred to as a swing drive mechanism for swinging the rear parts of the pair of dog leg shaped link members 3 and 4 in directions in which the rear parts move apart from and closer to each other.

(15) The chuck mechanism according to the present invention configured as described above clamps a pipe that is a workpiece as follows.

(16) First, the electric cylinder 13 is driven to rotate forward by control means (not shown) to advance the rod 13a of the electric cylinder, so that the swing rod 14 swings forward around the fixed point at the upper end 14a. The swing motion of the swing rod 14 is received by the flange 12a provided on the outer periphery of the cylindrical member 12 so that the cylindrical member 12 is slid forward along the shaft 1. When the cylindrical member 12 slides forward, the connecting link member 11 fixed to the cylindrical member 12 moves forward to cause the rear parts of the pair of dog leg shaped link members 3 and 4 to swing around the bent portions 3a and 4a in directions in which they move apart from each other, via the short link members 9 and 10.

(17) When the rear parts of the pair of dog leg shaped link members 3 and 4 swing in directions in which they move apart from each other, the front parts of the pair of dog leg shaped link members 3 and 4 swing around the bent portions 3a and 4a in directions in which they move closer to each other. This swing motion of the front parts of the pair of dog leg shaped link members 3 and 4 causes the pair of clamp members 7 and 8, which have the clamp surfaces 7a and 8a facing each other and are rotatably supported respectively at the distal end 3b of the dog leg shaped link member 3 and the distal end 5b of the parallel link member 5 disposed parallel to the link member 3, and the distal end 4b of the dog leg shaped link member 4 and the distal end 6b of the parallel link member 6 disposed parallel to the link member 4, to move in directions in which they approach as shown in FIG. 2 to clamp the pipe.

(18) Since the upper part 2a of the frame 2, the front part of the dog leg shaped link member 3, the parallel link member 5, and the clamp member 7, and the lower part 2b of the frame 2, the front part of the dog leg shaped link member 4, the parallel link member 6, and the clamp member 8 each form a structure known as a parallel link, the clamp surfaces 7a and 8a remain parallel as the clamp members 7 and 8 approach each other to clamp the pipe. Therefore, they make surface contact, or at least line contact with the pipe when clamping the pipe, so that they will hardly cause a dent, scar, etc. on the pipe.

(19) In the embodiment described above, the clamp surfaces 7a and 8a are formed as V-shaped grooves, so that the pipe moves along the V-shaped grooves of the clamp surfaces 7a and 8a when being clamped. Pipe centering has been achieved by the end of clamping so that the pipe can be clamped correctly. As shown in FIG. 3 and FIG. 4, pipes P of different diameters can be clamped from above and below uniformly in line contact at least at two locations, so that dents, scars etc. can hardly be formed on the pipe. Moreover, when the electric cylinder 13 that causes the clamp members 7 and 8 to approach each other via the link mechanism as described above is of a type that can control not only the start-up, stop, forward rotation, and reverse rotation but also the torque by way of control means, the chuck can clamp the pipe with an optimal clamping force in accordance with the pipe diameter and pipe material.

(20) When releasing the pipe that has been clamped, the electric cylinder 13 is driven to rotate reversely by control means (not shown), so that the rod 13a of the electric cylinder moves backward. The link mechanism described above then moves in opposite directions from those mentioned above to cause the clamp members 7 and 8 to move apart from each other to release the pipe.

(21) A rotary drive mechanism 20 may be provided to the chuck mechanism according to the present invention described above for rotating the horizontally arranged shaft 1 mentioned above around its axis.

(22) The rotary drive mechanism 20 may be configured as shown in FIG. 5 and FIG. 6, with a driving motor 21 set above the chuck mechanism. A pulley 22 mounted to a rotary shaft of the driving motor 21 and a pulley 23 provided to the shaft 1 of the chuck mechanism may be connected with a belt 24, so that, by rotating the driving motor 21, the shaft 1 is rotated around its axis, which in turn rotates the chuck mechanism provided at the distal end of the shaft 1.

(23) With such a rotary drive mechanism 20 provided to the chuck mechanism, the pipe clamped by the chuck mechanism can be rotated around its axis, so that the pipe can be bent to any direction by means of a supplementary pipe bending machine.

(24) Moreover, a transfer drive mechanism 30 may be provided to the chuck mechanism according to the present invention for moving the chuck mechanism along the axial direction of the shaft 1.

(25) As shown in FIG. 5 and FIG. 6, the transfer drive mechanism 30 may be configured with a table 31 on which the chuck mechanism is placed, guide rails 32 that movably support the table 31, a feed motor 33 provided on the underside of the table 31, a drive pinion 34 mounted to a rotary shaft of the feed motor 33, and a rack member 35 that is provided parallel to the guide rails 32 and receives the drive force from the feed motor 33 as the drive pinion 34 meshes therewith to cause the table 31 to move along the guide rails 32.

(26) With the transfer drive mechanism 30 described above provided to the chuck mechanism, the pipe clamped by the chuck mechanism can be moved along its axial direction, so that the pipe can be bent or cut at any position by means of a supplementary pipe bending machine or cutting machine.

(27) Furthermore, a swivel drive mechanism 40 may be provided to the chuck mechanism according to the present invention for swiveling the chuck mechanism around a vertical axis.

(28) As shown in FIG. 7, the swivel drive mechanism 40 may be configured as a hollow rotary actuator 41 interposed between the chuck mechanism and the table 31 the former is placed on, so that the hollow rotary actuator 41 directly swivels the chuck mechanism around a vertical axis. For the hollow rotary actuator 41, a device that has a hollow rotary table 42 and a stepping motor 43 for rotating the hollow rotary table 42 integral with the former may be used.

(29) With the swivel drive mechanism 40 described above provided to the chuck mechanism, the chuck mechanism can be swiveled around a vertical axis, so that various operations are possible such as retrieving a pipe to be processed, or discharging a processed pipe to a discharge chute on one side, etc.

(30) While one embodiment of the chuck mechanism according to the present invention has been described, it goes without saying that the present invention is not limited to the embodiment described above and various modifications and changes are possible.

(31) For example, the swing drive mechanism for swinging the rear parts of the pair of dog leg shaped link members 3 and 4 shown in the embodiment above is only one example. The present invention can adopt swing drive mechanisms of various configurations, as long as the mechanism can swing the rear parts of the pair of dog leg shaped link members 3 and 4 to move them apart from or closer to each other.

(32) The configurations of the rotary drive mechanism 20 for rotating the chuck mechanism around the axis of the shaft 1, the transfer drive mechanism 30 for moving the chuck mechanism along the axial direction of the shaft 1, and the swivel drive mechanism 40 for swiveling the chuck mechanism around the vertical axis shown in the embodiment above are only examples, and the present invention shall not be limited in any way by these configurations.

INDUSTRIAL APPLICABILITY

(33) The chuck mechanism according to the present invention described above enables downsizing of the device with a simple structure and has a wide open/close width of clamps so that it is capable of handling pipes of various diameters. The chuck mechanism can clamp pipes in surface contact or at least in line contact therewith, so that it hardly causes a dent, scar, etc. on the pipe. Therefore, the chuck mechanism is widely applicable as a device that clamps a pipe when cutting or bending the pipe.

REFERENCE SIGNS LIST

(34) 1 Shaft 2 Frame 2a Upper part of frame 2b Lower part of frame 3, 4 Pair of dog leg shaped link members 3a, 4a Respective bent portions of the pair of dog leg shaped link members 3b, 4b Respective distal ends of the pair of dog leg shaped link members 3c, 4c Respective rear ends of the pair of dog leg shaped link members 5, 6 Parallel link member 5a, 6a Respective rear ends of parallel link members 5b, 6b Respective front ends of parallel link members 7, 8 Pair of clamp members 7a, 8a Respective clamp surfaces of the pair of clamp members 9, 10 Short link member 11 Connecting link member 11a Central portion of connecting link member 12 Cylindrical member 12a Flange provided on outer periphery of cylindrical member 13 Electric cylinder 13a Rod of electric cylinder 14 Swing rod 14a Upper end of swing rod 20 Rotary drive mechanism 21 Drive motor 22, 23 Pulley 24 Belt 30 Transfer drive mechanism 31 Table 32 Guide rail 33 Feed motor 34 Drive pinion 35 Rack member 40 Swivel drive mechanism 41 Hollow rotary actuator 42 Hollow rotary table 43 Stepping motor