JP2005036923A - Tensile force imparting mechanism for traveling device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To make a traveling device lighter in weight and simpler in operation and obtain a desired tensile force by giving rocking motion to a turning member around a supporting shaft along a fixing shaft inserting through an arcuate slit to bring a tensile force imparting member into pressure contact with a traveling member. <P>SOLUTION: The mechanism for the traveling device is provided with the turning member having one end supported on a body crossing a travel passage for the traveling member for turning around the supporting shaft and the other end at which the arcuate slit is formed with a preset radius of curvature around the supporting shaft, the fixing shaft for fixing the turning member inserting through the arcuate slit to the body so as to be position adjustable at a preset turning angle around the supporting shaft, and the tensile force imparting member provided on the turning member for pressure contact with the traveling member being travelling. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a tension applying mechanism that applies tension to a traveling member such as a belt and keeps it in a tension state in a traveling device that pivots and moves an arm such as an articulated robot.

  For example, in an articulated robot, as a mechanism for driving the turning arm that moves the hand unit to a predetermined position, a servo motor that is rotatably supported by the base end and the distal end of the fixed arm and can be numerically controlled on one side, etc. 2. Description of the Related Art A traveling drive device is known in which a traveling member such as a belt is wound around a pair of rotating bodies to which an electric motor is connected, and a base end portion of a turning arm is fixed to an output shaft fixed to the rotating body on the distal end side. In this travel drive device, it is necessary to always keep the travel member to be wound from the need to rotate the output shaft in accordance with the amount of rotation of the electric motor, and a tension applying mechanism is provided for this purpose.

  As the tension applying mechanism, for example, as shown in Patent Document 1, a first pulley and a second pulley that are rotatably supported by a root portion and a tip portion of a first arm, respectively, and the first pulley And a belt wound around a second pulley, and two rollers contacting the outside on both sides of the belt across a center line connecting the centers of the first pulley and the second pulley. In a belt tension adjusting method for an articulated robot that adjusts the tension of the belt by displacing the belt in a direction perpendicular to a line, the two rollers are supported on a balance rod so as to be rotatable with a space between each other. The balance rod is rotatably supported by a support shaft provided at an intermediate point between the rollers and on the center line, and the balance rod is Mechanism for adjusting the belt tension against the two rollers in the belt by rotating around the lifting axis is known.

However, the tension adjustment mechanism shown in Patent Document 1 forms two slits formed in an arc shape on the arm itself of the industrial robot and pivotally supports the balance rod between a pair of pulleys around which the belt is wound, It was necessary to rotatably support the tension roller on both sides of the balance rod.

For this reason, this tension adjusting mechanism has a problem of increasing the weight of the arm itself. In particular, in order to move the hand unit to a predetermined position in a short time, it is necessary to reduce the weight of the arm itself because it is necessary to drive the arm itself at a high speed. However, in the tension adjustment mechanism described above, Weight increase was inevitable and high-speed turning was difficult. For this reason, the fatal fault that the movement time of the hand part becomes long is generated.

Further, the tension adjusting mechanism described above has to form an arc-shaped slit in the arm itself as a member to be attached, and it is difficult to employ other members.
JP-A-10-277984

  The problems to be solved by the present invention are that the traveling device itself cannot be reduced in weight and that tension cannot be easily adjusted.

In the present invention, an arc-shaped slit having a predetermined radius of curvature centered on the support shaft is formed at the other end of the main body that intersects the travel path of the travel member. The rotation member provided on the rotation member, the fixed shaft for inserting the rotation slit into the main body through the arc-shaped slit and fixing the rotation member at a predetermined rotation angle around the support shaft, and the rotation member are provided. And a tension applying member that is in pressure contact with the traveling member.
It is characterized by.

  The present invention can obtain a desired tension by pressing the tension applying member against the traveling member by swinging the rotating member around the support shaft along the fixed shaft that passes through the arc-shaped slit, and is lightweight. And simplification of operation.

The present invention will be described below with reference to the drawings showing embodiments.
1 and 2, the industrial robot to which the tension applying mechanism 1 according to the present invention is attached drives the turning arm 5 to turn with respect to the fixed arm 3 and rotates the turning shaft 7 provided at the tip of the turning arm 5. The hand unit (not shown) is moved to move between predetermined positions so that the direction is directed to a predetermined direction.

A pair of toothed pulleys 13 as a rotating body connected to an electric motor 11 such as a servo motor capable of numerical control at one end are rotatably supported on the base end portion and the tip end portion of the fixed arm 3, and these toothed pulleys are supported. A toothed belt 15 as a running member is wound around 13.

  The tension applying mechanism 1 is attached to the fixed arm 3 located on the base end side. The tension applying mechanism 1 has a flat fan shape, and a support plate in which a shaft support hole 17a is formed at the center of the fan and a movable plate 17 having a slit 17b formed along an arc on the outer periphery of the fan is inserted through the shaft support hole 17a. 19 is supported to rotate. The movable plate 17 is fixed by a fixing screw 21 inserted through the slit 17b and screwed to the fixed arm 3.

When the fixing screw 21 is loosened with respect to the fixed arm 3, the movable plate 17 is rotated about an angle of about 90 degrees around the support shaft 19 by the fixing screw 21 slidably contacting the slit 17 b. A tension roller 22 is attached to the movable plate 17 so as to intersect the toothed belt 15. The support shaft 19 may have a screw structure that can be screwed to the fixed arm 3 like the fixed screw 21.

  The toothed pulley 13 located on the distal end side of the fixed arm 3 is fixed with a shaft member 23 having an axial length protruding to the outside of the fixed arm 3, and the base end portion of the swivel arm 5 is fixed to the shaft member 23. Yes. A boss 25 having teeth formed on the outer periphery thereof is coaxially fixed to the shaft member 23 located in the base end portion of the swivel arm 5. Further, a rotating body 27 such as a toothed pulley is rotatably supported at the tip of the turning arm 5, and a toothed belt 29 constituting a traveling member is wound around the boss 25 and the rotating body 27. A rotating shaft 31 is coaxially fixed to the rotating body 27, and a hand portion is fixed to the shaft end of the rotating shaft 31.

  A tension applying mechanism 33 is provided on the swivel arm 5 corresponding to the traveling path of the toothed belt 29. The tension applying mechanism 33 has the same configuration as the tension applying mechanism 1 described above, 35 for the corresponding movable plate, 35a for the shaft support hole, 35b for the slit, 37 for the support shaft, 39 for the fixing screw, The tension roller is denoted by reference numeral 41 and will not be described in detail.

Next, the operation of the tension applying mechanisms 1 and 33 will be described.
First, the turning operation of the hand portion will be described. When the toothed belt 15 is caused to travel in a predetermined direction by the toothed pulley 13 on the proximal end side that rotates by rotating the electric motor 11, the toothed belt 15 The toothed pulley 13 on the tip side is rotated according to the travel amount. Thereby, the shaft member 23 fixed coaxially with the toothed pulley 13 on the distal end side is rotated, and the turning arm 5 whose base end portion is fixed to the shaft member 23 is turned according to the rotation core of the shaft member 23.

At this time, since the toothed belt 29 is meshed with the boss 25 fixed to the shaft member 23, the toothed belt 29 is rotated by the boss 25 rotating integrally with the shaft member 23 as the swivel arm 5 rotates. By rotating in the predetermined direction and rotating the rotating body 27, the hand unit is rotated while being swung and the posture is controlled in a predetermined direction.

  When the toothed belts 15 and 29 that run along with the turning and rotation of the revolving arm 5 and the hand portion described above are extended and relaxed due to use over time, the rotational state of the revolving arm 5 and the hand portion becomes unstable. In order to avoid this, it is necessary to adjust the toothed belts 15 and 29 to be in a tension state.

  The method will be described below. First, the fixing screw 21/39 is loosened so that the movable plate 17/35 can swing around the support shaft 19/37. When a screw is used as the support shaft 19/37, the movable plate 17/35 is made swingable after being loosened together with the fixing screw 21/39.

Next, in the above state, the movable plate 17/35 is swung toward the toothed belt 15/29 side and the tension roller 22/41 is pressed against the outer surface of the toothed belt 15/29 to be tensioned, and then the fixing screw 21 / 39 is screwed to fix the movable plate 17/35. At this time, the fixing screw 21/39 is in sliding contact with the inside of the slit 17b / 35b of the movable plate 17/35 so that the movable plate 17/35 can swing within the arc width of the slit 17b / 35b. (See Figure 3)

In the present embodiment, the movable plate 17/35 is swung around the support shaft 19/37, and the tension roller 22/41 is brought into pressure contact with the outer surface of the toothed belt 15/29 to be adjusted to a tension state. At that time, the tension can be adjusted by a simple operation of loosening or tightening the fixing screw 21/39, and the adjustment operation can be made efficient.

In the first embodiment, the tension is adjusted by swinging the movable plates 17 and 35 and pressing the tension roller 22/41 against the outer surface of the toothed belt 15/29. In this case, the configuration is as shown in FIG.

That is, the nut member 53 meshed so that the screw member 51 is screwed to the fixed arm 3 and the swing arm 5 is rotatably supported, and is swingably and fixedly supported in the same manner as the mobile phone 1. A screw receiving member 57 that rotatably supports the tip of the screw member 51 is provided on the movable plate 17/35 so as to be rotatable.

And the structure which adjusts the press-contact force of the tension roller 59 with respect to a toothed belt by rocking | fluctuating the movable board 55 by screwing or screwing the screw member 51 with respect to the nut member 53 may be sufficient. (See Figure 5)

  The above description has been given as a tension applying mechanism of a toothed belt adopted as a turning drive mechanism of an arm for turning the hand part. However, the present invention can be applied to, for example, a belt adopted as a belt conveyor or a reciprocating linear movement mechanism. It is good also as a mechanism which gives a desired tension to a running member.

  In the present invention, a toothed belt is used as the traveling member. However, when a chain is used as the traveling member, a mechanism using a sprocket as the tension applying member may be used.

It is explanatory drawing which shows the example which actualized the tension | tensile_strength provision mechanism of the traveling apparatus which concerns on this invention. It is a disassembled perspective view of the tension | tensile_strength provision mechanism of a traveling apparatus. It is explanatory drawing which shows a tension | tensile_strength provision effect | action. It is explanatory drawing of the tension | tensile_strength provision mechanism which concerns on Example 2. FIG. It is explanatory drawing which shows the effect | action of Example 2. FIG.

Explanation of symbols

1. 33-Tension applying mechanism, 3-fixed arm, 5-swing arm, 15.29-toothed belt as traveling member, 17.35-movable plate as rotating member, 17b, 35b-slit, 22. 41-Tension roller as tension applying member

Claims (5)

In a traveling device in which a traveling member is stretched between at least a pair of rotating bodies that are rotatably supported at a predetermined interval, one end of the traveling body intersects with a traveling path of the traveling member so that one end thereof rotates about a support shaft. And a rotating member having an arc-shaped slit with a predetermined radius of curvature centered on the support shaft at the other end, and a rotating member inserted into the main body through the arc-shaped slit, with the support shaft as the center A tension applying mechanism comprising: a fixed shaft that is fixed so that position adjustment is possible at a predetermined rotation angle; 2. The tension applying mechanism according to claim 1, wherein the traveling member is a belt and the rotating body is a pulley. 2. A tension applying mechanism for a traveling device according to claim 1, wherein the traveling member comprises a chain and the rotating body comprises a sprocket. The fixed axis | shaft of Claim 1 is the tension | tensile_strength provision mechanism of the traveling apparatus which used the volt | bolt. The rotating member according to claim 1 supports the shaft end portion of the screw member engaged with the nut member rotatably supported by the main body so as to be swingable, and the rotating member is moved along with the rotation operation of the screw member. A tension applying mechanism of the traveling device that rotates around the support shaft.

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