JP2006334736A - Flexural arm - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily provide a flexural arm capable of simply setting a desired flexural state at low cost. <P>SOLUTION: This flexural arm is constituted of a hollow cylindrical first arm 1, a core shaft 2 to be inserted through the inside of the first arm 1 free to advance and retreat and a second arm 3 on an end part of which a pair of bearing pieces 4, 4 is formed in a forked state and an outer periphery of which is formed in a spherical surface shape or in a circular arc surface shape with its center positioned between fork ends of the bearing pieces , a tip end part 8 of the core shaft is projected from a tip end surface of the first arm, the second arm is connected to the tip end part free to rotate by inserting a support shaft 10 through into the tip end part and an outer peripheral surface of the bearing pieces is made pressure contact with the tip end surface of the first arm and the second arm is fixed on the first arm at a desired bending angle by tracking the core shaft at the rear of the first arm. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a bendable arm that can be set to a desired refraction state.

  FIG. 5 shows, for example, a part of a transfer device such as a robot conventionally used to transfer a workpiece w between pressing processes in a steel sheet press forming line in an automobile factory, and is supported by an arm r. A plurality of mounting portions b are provided on one side of the reciprocating body a, and an articulated arm d having a vacuum suction pad c at the tip is fixed by inserting a base portion e into each mounting portion, and f is a vacuum suction A hose g is a fastening screw provided to fix the position and angle of the vacuum suction pad. As is well known, this transfer device is configured to hold the workpiece by adsorbing the vacuum suction pad c to the flat surface of the workpiece w.

On the other hand, the work auxiliary arm shown in the following Patent Document 1 is formed by providing a locking means on a universal joint having a spherical body so that a grasped object is held and fixed at a desired angle. Further, in the vacuum suction pad assembly shown in the following Patent Document 2, the vacuum suction pad for holding the workpiece is directed in a free direction by two spherical joints, and both spherical joints are formed at a desired angle by one fastening bolt. It is comprised so that it can hold | maintain and fix to. Furthermore, in the following Patent Document 3 relating to the patent application of the present applicant, a vacuum suction pad is provided at the tip of a multi-joint arm, and the vacuum suction pad is directed in a required direction by bending the multi-joint arm. A vacuum suction pad setting device that can be set is disclosed.
JP-A-9-130934 U.S. Pat. No. 4,957,318 JP 2003-181786 A

By the way, in the conventional articulated arm, for example, if the vacuum suction pad is to be fixed at a required position and angle, several fixing screws must be tightened, and the tightening operation or the tightening releasing operation is troublesome. There was a problem that the position and angle of the vacuum suction pad were likely to fluctuate while operating one fixing screw.
Further, any of the bendable arms described in the above-mentioned patent documents can realize the flexibility in the direction of refraction of the joint part by a spherical body, but it is generally expensive to process the spherical body by metal. In addition to the disadvantages, there was a disadvantage that the weight increased.
Accordingly, the present invention aims to provide a bendable arm that can be easily tightened or released, and can be set in a desired refraction state without using a spherical body as an essential component. .

For this purpose, the bendable arm described in claim 1 has a hollow cylindrical first arm, a core shaft that is slidably inserted into the first arm, and a pair of bearing pieces formed in a bifurcated shape at the end. And the outer periphery of the bearing piece comprises a second arm formed in a spherical or arcuate shape centered between the two forks of the bearing piece, and the tip of the core shaft projects from the tip of the first arm The distal end is loosely inserted between the two forks of the bearing piece of the second arm, and a support shaft is inserted through the distal end to rotatably connect the second arm to the distal end. By pulling to the rear of one arm, the outer peripheral surface of the bearing piece is pressed against the tip surface of the first arm, and the second arm is fixed to the first arm at a desired refraction angle. Features.
The invention described in claim 2 is characterized in that, in the bendable arm, a core shaft is inserted into the first arm so as to be movable forward and backward and rotatable.
According to a third aspect of the present invention, in the bendable arm, a bolt is screwed into the rear end portion of the core shaft, the head portion of the bolt projects from the rear end surface of the first arm, and the bolt is connected to the core shaft. It is characterized in that the core shaft is pulled backward by being screwed into.
According to a fourth aspect of the present invention, in the bendable arm, a spring washer is interposed between the rear end surface of the first arm and the head of the bolt.

In the bendable arm described in claim 1, the vacuum suction pad or the like can be easily set to a desired refraction state by moving the core shaft forward and backward, and the spherical body is not an essential component. Cost is reduced.
In the bendable arm described in the second aspect, the second arm can be refracted in a 360 ° free direction by rotating the core shaft.
In the bendable arm described in the third aspect, the tightening operation and the tightening releasing operation can be easily performed by the bolt.
In the bendable arm described in the fourth aspect, the core shaft can always be held in an appropriate traction state by the elasticity of the spring washer.

  In this embodiment, the position and angle of the vacuum suction pad can be freely set by a refracting arm according to the present invention. FIG. 1 is an external perspective view, FIG. 2 is a longitudinal sectional view of a main part, and FIG. FIG. In the figure, 1 is a hollow cylindrical first arm, 2 is a core shaft that is inserted into the first arm so as to be able to advance and retract, and 3 is a pair of bearing pieces 4 and 4 at the end. A second arm is formed and the outer periphery of the bearing piece is formed in a spherical shape centered between the two forks of the bearing piece. In addition, 5 is a vacuum suction pad fixed to the tip of the second arm 3, 6 is an intake plug provided on one side of the second arm 3, 7 is an intake hose connected to the intake plug, A work (not shown) is adsorbed to the vacuum suction pad 5 by causing the vacuum suction pad 5 to suck air through the intake hose.

  The distal end portion 8 of the core shaft 2 protruding from the distal end surface of the first arm 2 is formed flat and a through hole 9 is formed in the distal end portion. Then, the tip 8 is loosely inserted between the forks of the bearing pieces 4 and 4 of the second arm, and the support shaft 10 supported by the bearing piece is inserted into the through hole 9 to thereby insert the tip 8 into the tip 8. Two arms 3 are rotatably connected. In addition, 11 is a plain washer that is inserted through the support shaft 10, and 12 is a clip that is engaged with the tip of the support shaft 10 to prevent the support shaft from being removed. Reference numeral 13 denotes a washer interposed between the front end surface of the first arm 1 and the bearing pieces 4, 4. The surface of the washer facing the bearing pieces 4, 4 has a spherical shape along the spherical surface of the outer periphery of the bearing piece. Is formed.

  Further, as shown in FIG. 2, a screw hole 14 is formed at the rear end portion of the core shaft 2, and a bolt 15 is screwed into the screw hole. 16 is a bush loosely fitted to the rear end of the first arm 1, and 17 is a spring washer disposed on the outer surface of the bush. The bolt 15 penetrates the bush and the spring washer, and the head 18 of the bolt protrudes from the rear end surface of the first arm 1. Therefore, by engaging the head 18 with a hexagon wrench or the like and screwing the bolt into the core shaft 2, the head presses the rear end surface of the first arm 1 via the spring washer 17 and the bush 16. The reaction force causes the core shaft 2 to be pulled rearward, and the outer peripheral surfaces of the bearing pieces 4 and 4 are pressed against the distal end surface of the first arm 1 via the washer 13. For this reason, after the second arm 3 is adjusted to a desired refraction angle with respect to the first arm 1, the bolt 15 is rotated in the tightening direction, and the core shaft 2 is pulled backward, whereby the washer 13 is moved to the bearing piece 4. , 4 can be pressure-bonded to each other and the second arm can be fixed to the first arm at a desired refraction angle. Since the core shaft 2 is inserted into the first arm so as to be movable forward and backward, and rotatable, the second arm can be refracted 360 degrees in a free direction by rotating the core shaft 2. The bolt 15 is tightened after being refracted in a desired direction.

  Reference numeral 20 denotes a fixing jig for connecting the first arm 1 perpendicularly to an arm (not shown) of a transfer device such as a robot, and a pair of substantially U-shaped clamps 21 and 22 are orthogonal. The two clamps are arranged at the same time and are rotated in a predetermined direction so that both the clamps can be tightened simultaneously. For this reason, after loosening the bolt 23 and adjusting the position of the first arm 1 so that the vacuum suction pad 5 faces the workpiece, the bolt 23 can be tightened.

  In the bendable arm configured in this way, a hexagonal wrench or the like is engaged with the bolt head 18 and the bolt 15 is loosened so that the vacuum suction pad 5 faces the workpiece suction surface directly in front of the first arm. On the other hand, the second arm 3 can be refracted, and by tightening the bolt 13 in this state, the refraction angle of the second arm with respect to the first arm is fixed. For this reason, the position and angle of the vacuum suction pad 5 can be easily set in a desired state in a short time on the arm portion of the robot transfer device, and the workpiece can be reliably vacuum-sucked.

  Since the spring washer 17 pulls the core shaft 2 with elasticity due to its elasticity when the bolt 15 is tightened, the spring washer 17 can appropriately hold the pressure applied to the outer peripheral surfaces of the bearing pieces 4 and 4.

  On the other hand, FIG. 4 shows another embodiment of the present invention. In this embodiment, the outer periphery of the bearing pieces 4, 4 of the second arm 3 is formed in an arcuate shape. For this reason, when the bolt 15 is tightened, the arc surface comes into pressure contact with the distal end surface of the first arm 1 via the washer 13. As described above, the outer periphery of the bearing pieces 4 and 4 may not be necessarily spherical as in the above-described embodiment, but may be formed in an arc surface. By making the arc surface, processing becomes easy and manufacturing costs are reduced. It is also possible. In the present invention, not all the components and shapes shown in the above embodiments are necessarily essential in the present invention. For example, the washer 13 and the bush 16 can be omitted. Needless to say, a magnetic suction device, a robot hand, or the like can be provided instead of the vacuum suction pad.

As described above, the bendable arm of the present invention can fix the second arm in a desired refraction state by pulling the core shaft that is inserted into the first arm. Or it can be used as a stand for supporting a display or the like in a desired direction.
Further, by appropriately setting in advance the force for pulling the core shaft backward by an elastic body such as a spring washer, an appropriate rotational resistance can be obtained when the second arm is rotated. The bendable arm can be widely used to support various articles as a substitute for the bendable arm using a conventional spherical joint.

The perspective view of the bendable arm which shows embodiment of this invention. The longitudinal cross-sectional view of the principal part of the bendable arm of FIG. The disassembled perspective view of the principal part of the bendable arm of FIG. The disassembled perspective view of the principal part of the bendable arm which shows other embodiment of this invention. The perspective view of the conveying apparatus currently used for the steel plate press molding line of the conventional automobile factory.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 1st arm 2 Core shaft 3 2nd arm 4 Bearing piece 5 Vacuum suction pad 8 Tip part of core shaft 9 Through-hole 10 Support shaft 13 Washer 14 Screw hole 15 Bolt 17 Spring washer 18 Bolt head

Claims (4)

  A hollow cylindrical first arm, a core shaft that is inserted into the first arm so as to be able to advance and retreat, a pair of bearing pieces is formed in a bifurcated shape at the end, and the outer periphery of the bearing piece is the two of the bearing pieces. A second arm formed in a spherical or arcuate shape centered on the crotch, the tip of the core shaft protrudes from the tip of the first arm, and the tip of the bearing piece of the second arm The second arm is rotatably connected to the tip by loosely inserting between the two forks and a support shaft is inserted into the tip, and the core shaft is pulled to the rear of the first arm to A bendable arm characterized in that an outer peripheral surface is pressed against a front end surface of a first arm and a second arm is fixed to the first arm at a desired refraction angle.   The bendable arm according to claim 1, wherein a core shaft is inserted into the first arm so as to be movable forward and backward and rotatable.   A bolt is screwed into the rear end of the core shaft, the head of the bolt is protruded from the rear end surface of the first arm, and the core shaft is pulled backward by screwing the bolt into the core shaft. The bendable arm according to claim 1 or 2, wherein the bendable arm is provided.   The bendable arm according to claim 3, wherein a spring washer is interposed between the rear end surface of the first arm and the head of the bolt.

Images