WO2000021721A1 - Robot arm - Google Patents

Abstract

A robot arm capable of rotating primary and secondary arms and the like through 360 degrees to infinity, optionally increasing or reducing the distance from the center of rotation of the robot arms to a finger arm installed at the front end of the robot arm, and optionally controlling the vertical length of the robot arms. A robot arm as described above, wherein at any position in which the robot arm is infinitely rotating, at any position in which the distance from the center of rotation of the robot arm to the finger arm is optionally increased or reduced, and at any position in which the height of the robot arm is optionally increased or reduced, the robot is capable of performing a motion for attracting work or the like by an attracting beak installed on the finger arm.

Description

 Specification

Robot arm technical field

 BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a robot arm having a finger arm provided with a suction beak on the distal end side, and to a robot arm capable of performing a rotary motion about a rotation axis and capable of moving up and down in a vertical direction. . In particular, according to the present invention, in the above-described robot arm, the robot arm can be rotated any number of times at least 360 degrees around the rotation axis, and the distance from the rotation axis to the suction beak can be expanded and contracted. 2. Description of the Related Art A robot arm capable of performing a suction operation of a workpiece by the suction beak at any position where an infinite rotation operation or a lifting operation is performed as described above.

 The invention related to the rotation device of the articulated robot has been proposed. For example, there is Japanese Patent Laid-Open No. 61-273636. There has also been proposed a robot rotation mechanism having a mechanical stopper and capable of rotating more than 360 degrees (Japanese Patent Application Laid-Open No. 61-273636). Furthermore, there is also a proposal of a turning device for an industrial robot having a rotating body such as a turning arm that rotates within a predetermined range (Japanese Patent Application Laid-Open No. 4-275758).

 However, it is possible to rotate the rotary shaft any number of times more than 360 degrees, and it is also possible to expand and contract the distance from the rotary shaft to the suction beak on the finger arm tip side. A robot arm capable of performing an operation of sucking a workpiece or the like by the suction beak at any position where the endless rotation operation is performed, and at any position of the raising / lowering operation of the arm has not been proposed. . Disclosure of the invention

According to the present invention, a parent arm, a child arm, etc., constituting a robot arm can be rotated indefinitely by more than 360 degrees, The purpose is to propose a robot arm that can arbitrarily expand and contract the distance from the robot arm to the finger arm provided on the distal end side of the robot arm, and can adjust the vertical height of the robot arm as desired. .

 Further, the present invention provides a robot arm as described above, in which the distance from the center of rotation of the robot arm to the finger arm is arbitrarily expanded or contracted at any position where the robot arm rotates infinitely. A robot arm capable of performing an operation of sucking a work or the like by a suction beak provided on the finger arm at any position where the height of the robot arm is arbitrarily raised and lowered in the vertical direction. The purpose is to propose.

 The robot arm proposed by the present invention to solve the above object is configured as follows.

 The basic configuration of the robot arm according to the present invention includes an inner / outer double shaft composed of an inner shaft and an outer shaft, each of which has a lower end rotatably attached to a lifting plate, and an upper end side of the outer shaft. A parent arm whose base end is rotatably mounted; a child arm whose base end is rotatably mounted on a first shaft erected on the distal end of the parent arm; And a finger arm whose base end is rotatably attached to a second shaft erected on the distal end of the arm.

 The inner shaft and the outer shaft are provided with a rotation detector and a rotation force input means, respectively, and a first timing pulley and a second timing pulley are fixed to an upper end side, respectively. The first timing pulley and the second timing pulley are timing pulleys that are rotatably mounted on the first shaft, and are the third timing pulleys that are vertically combined. A pulley and a fourth timing pulley are connected to each other by a first evening timing belt and a second timing belt, and the base end of the child arm is connected to the upper end of the third timing pulley. By being fixed, it is rotatably attached to the first shaft.

Further, a fifth timing pulley is further fixed to the first shaft, and the fifth timing bouley is rotatably attached to a second shaft erected on the distal end side of the child arm. On the sixth timing platform and the third evening Therefore, the finger arms are connected to each other, and are fixed to the sixth timing pulley so as to be rotatably attached to the second shaft. Here, in the robot arm of the present invention having the above configuration, the first, second, third, fourth, fifth, and sixth timing pulleys are formed as toothed pulleys, respectively. A predetermined tooth number ratio is defined between the number of teeth of each timing pulley.

 By adopting the above configuration, the robot arm of the present invention can rotate infinitely over 360 degrees around the rotation axis, and can freely set the distance from the rotation center to one finger. Can be expanded and contracted. In addition, the infinite rotation can be performed in either the forward or reverse direction, so that the parent arm and the like can be moved and rotated with a minimum amount of rotation. The robot can be moved and rotated to a desired position, which can improve the efficiency of work using a robot.

 Another robot arm proposed by the present invention is the above-mentioned robot arm, wherein the finger arm further includes a suction beak on a tip side thereof, and the inner shaft has a hollow cylindrical shape with upper and lower ends closed. The upper end side of the hollow portion of the inner shaft is provided with a ventilation portion in the parent arm, a ventilation portion provided in the first shaft, a ventilation portion in the child arm, and a ventilation portion provided in the second shaft. A distal end of a suction pipe, which communicates with a suction beak on the distal end side of the finger arm through a ventilation portion in the finger arm, and has a proximal end connected to a gas supply / discharge means at a lower end of the hollow portion of the inner shaft; The robot arm has a side opening inserted over a predetermined vertical height.

According to the robot arm of the present invention configured as described above, at any position where the robot arm is rotated infinitely, and at any position where the distance from the center of rotation of the robot arm to the finger arm is arbitrarily expanded and contracted. Furthermore, at any position where the height of the robot arm is arbitrarily raised and lowered in the vertical direction, the operation of sucking a work or the like by the suction beak provided on the finger arm can be performed. BRIEF DESCRIPTION OF THE FIGURES FIG. 1 is a sectional view in which a part of the embodiment of the present invention is omitted. FIG. 2 is a plan view in which a part of the embodiment shown in FIG. 1 is omitted. FIG. 3 is a perspective view for explaining a rotating state of the parent arm and the like when the distance from the center of rotation to the tip of the finger arm is expanded and contracted. FIG. 4 is a perspective view in which a part of the rotation state of a parent arm and the like is omitted. FIG. 5 is a cross-sectional view partially illustrating a connection structure of a parent arm and the like, with parts omitted. FIG. 6 is a partially omitted cross-sectional view showing a connection example of a ventilation hole in a central portion of the rotary motion. BEST MODE FOR CARRYING OUT THE INVENTION

 Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

 As shown in FIG. 1, one side of a lifting plate 6 is attached to a ball screw 4 that is rotatably installed upright between the lower plate 2 of the machine casing 1 and the upper plate 3 (the left side in FIG. 1). ) The cylindrical nut 5 fixed to is screwed.

 An electromagnetic brake 50 is mounted on the upper end side of the ball screw 4, and a timing pulley 41 is fixed. The timing pulley 41 is connected to a timing pulley 39 fixed to the rotating shaft of a stepping motor 38 disposed on a support plate 37 supported by the machine frame 1 by a timing belt 40. The ball screw 4 rotates by receiving rotation input from the stepping motor 38.

 On the other side (the right side in FIG. 1) of the elevating plate 6, the lower end of the inner shaft 8 of the robot arm is rotatably mounted. The outer shaft 9 of the robot arm is coaxially fitted on the inner shaft 8, and the outer shaft 9 is supported by the inner shaft 8 as shown in FIG. With this configuration, the inner shaft 8 and the outer shaft 9 that form the inner and outer double shafts of the robot arm have their lower ends rotatably attached to the elevating plate 6, respectively.

The basic configuration of the robot arm of the present invention is as follows: a parent arm 24 whose base end is rotatably attached to the upper end of the outer shaft 9 described above; The base arm is rotatably mounted on the first shaft 26, the base end of which is rotatably mounted, and the second shaft 27, which is set up on the distal end of the child arm 25, is rotatable on the base end. freely And a finger arm 28 provided with a suction beak 49 on the distal end side.

 As shown in FIG. 1, timing pulleys 11 and 10 and sensor dogs 13 and 12 are fixed to lower ends of the inner shaft 8 and the outer shaft 9, respectively. On the other hand, the lower end of the bracket 14 is fixed to the lifting plate 6, and the photosensors 16 and 15 arranged at positions facing the sensor dogs 13 and 12 are attached to the bracket 1. Installed on 4. These form a rotation detector attached to the inner shaft 8 and the outer shaft 9.

 Further, as shown in FIG. 2, the timing pulleys 19, 20 fixed to the output shafts of the stepping motors 17, 18 mounted on the elevating plate 6, and the inner shaft 8, Timing pulleys 11 and 10 fixed to the lower end of the outer shaft 9 are connected by timing belts 21 and 22 respectively, and are attached to the inner shaft 8 and the outer shaft 9 by these. Thus, a rotating force input means is configured.

 At the upper end side of the inner shaft 8 and the outer shaft 9, a first timing pulley 29 and a second evening pulley 23 are fixed (FIGS. 1 and 5). The first timing pulley 29 and the second timing pulley 23 are rotatably attached to a first shaft 26 fixedly provided on the leading end side of the parent arm 24. The third pulley 30 and the fourth evening pulley 32 and the first timing belt 31 and the second evening belt 33 are combined by the timing pulley and upper and lower. It is connected (Figure 1, Figure 5). It is preferable to arrange a guide pulley 56 as shown in FIG. 1 between the first timing belt 31 and the second timing belt 33, but such a guide pulley 56 is arranged. It is also possible to adopt a configuration that is not stored.

The child arm 25 is rotatably attached to the first shaft 26 because its base end is fixed to the upper end of the third timing tree 30. As shown in FIGS. 1 and 5, a fifth timing pulley 34 is further fixed to the first shaft 26, and the fifth timing pulley 34 is connected to the distal end of the child arm 25. A sixth timing tree 35 rotatably attached to a second shaft 27 fixedly mounted on the side and a third evening belt 36 I have. It is preferable to arrange a guide pulley 57 in the middle of the third timing belt 36 as shown in FIG. 1, but it is also possible to adopt a configuration in which such a guide pulley 57 is not provided. It is.

 Further, the finger arm 28 having the suction beak 49 on the distal end side is rotatable about the second shaft 27 because its base end side is fixed to the sixth timing pulley 35. Attached to.

 The vertical direction of the parent arm 24, the child arm 25, and the finger-arm 28 (hereinafter, these are collectively referred to as "parent arm 24, etc.") in the robot arm of this embodiment. Is performed as follows.

 When the stepping motor 38 is driven to apply a rotating force to the ball screw 4 and the ball screw 4 is rotated, the cylindrical nut 5 moves up and down in the directions of arrows 4 2 and 4 3 according to the rotation direction of the ball screw 4 (see FIG. 1). Thus, the elevating plate 6 and the inner shaft 8 and the outer shaft 9 whose lower ends are rotatably attached thereto are also moved up and down in the directions of arrows 42 and 43. Therefore, the parent arm 24 whose base end is rotatably attached to the upper end of the outer shaft 9 also moves up and down in the directions of arrows 42 and 43, and the raising and lowering operations of the parent arm 24 and the like are performed. .

 The stepping motor 38 is provided with a sensor dog 51 and a photo sensor 52, as shown in Fig. 1, so that the rotation of the stepping motor 38 is detected, and the desired rotation is provided to the parent arm 24 or the like. Up and down movement can be performed. In addition, the operation for extending and contracting the distance L (FIG. 3) from the inner / outer double shaft consisting of the inner shaft 8 and the outer shaft 9 to the tip of the finger arm 28 is performed as follows.

 Stepping motor overnight 17 is stopped, and outer shaft 9 is prevented from rotating. On the other hand, the stepping motor 18 is operated, and only the inner shaft 8 is rotated, for example, in the direction of arrow 59 in FIG. The first pulling pulley 29 fixed to the upper end of the inner shaft 8 tries to rotate in the direction of arrow 59 as the inner shaft 8 rotates, and this rotational force is transmitted through the first evening belt 31. To the third timing tree 30.

Therefore, the third timing pulley 30 and the fourth evening pulley 32 formed integrally therewith are similarly driven in the directions indicated by arrows 59 around the first shaft 26. Try to rotate.

 However, the fourth timing pulley 32 is connected to the second timing pulley 23 fixed to the upper end side of the outer shaft 9 which is prevented from rotating by the second timing belt 33. Therefore, the third timing pulley 130 and the fourth sunset pulley 32 cannot rotate in the direction of arrow 59 around the first shaft 26.

 Therefore, the third and fourth timing pulleys 30 and 32 maintain the tension of the first and second evening imaging belts 31 and 33 while maintaining the inner shaft 8 and the first timing pulley. 29 In response to the rotational movement in the direction of arrow 9 in the direction of arrow 9, the outer shaft 9 is rotated while rotating in the direction of arrow 5 (Fig. 3, Fig. 4) around the first axis 26 in the direction of arrow 5 It will rotate (revolve) in the direction indicated by arrow 5 as the center of the arrow. Along with this, the first shaft 26 also rotates (revolves) in the direction indicated by the arrow 53 around the outer shaft 9 as the center of rotation, so that the first shaft 26 is fixedly erected on the distal end side. The parent arm 24 also rotates around the outer shaft 9 in the direction of arrow 53 (FIG. 4).

 On the other hand, the slave arm 25 is rotatably attached to the first shaft 26 because its base end is fixed to the upper end of the third timing pulley 130. As the third timing pulley 30 rotates (rotates) in the direction indicated by the arrow 54 around the first shaft 26 (FIGS. 3 and 4), the third timing pulley 30 also rotates about the first shaft 26. Arrow 5 Rotate in 4 directions (Figs. 3 and 4).

A sixth timing pulley 135 is rotatably mounted on a second shaft 27 fixedly provided on the distal end side of the slave arm 25. The sixth timing pulley The third timing belt 36 is connected to a fifth timing pulley 34 fixed to the first shaft 26. Here, as described above, the first shaft 26 and the fifth timing pulley 34 revolve around the inner shaft 8 and the outer shaft 9 as the center of rotation as shown by an arrow 53 (FIG. 4). However, since the first shaft 26 is fixed to the parent arm 24 and stands upright, it does not rotate. Therefore, the sixth timing pulley 135 rotatably attached to the second shaft 27 is connected to the first shaft 26 of the child arm 25 to which the second shaft 27 is fixed at its tip. Rotation in four directions (Fig. 3) and arrow 5 on the first shaft 26 to which the fifth timing pulley 134 is fixed With the rotation in the direction (FIG. 3), it rotates (rotates) in the direction of arrow 55 (FIGS. 3 and 4). The finger arm 28 rotatably attached to the shaft 27 also rotates in the direction of arrow 55 (FIGS. 3 and 4).

 By the movement described above, the distance L (FIG. 3) from the inner / outer double shaft of the inner shaft 8 and the outer shaft 9 which is the center of the rotation of the robot arm of the present invention to the tip of the finger arm 28 expands and contracts. Is done.

 The base end of the parent arm 24 is rotatably attached to the upper end of the outer shaft 9, and the base end of the child arm 25 is fixed to the distal end of the parent arm 24. By being fixed to the upper end of a third timing pulley 130 rotatably attached to the first shaft 26, the third timing pulley 130 is rotatably attached to the first shaft 26, and the finger arm The base end side of 28 is fixed to the upper end side of a sixth timing pulley 35 rotatably attached to a second shaft 27 fixed to the distal end side of the sub arm 25. By rotating the inner shaft 8 more than 360 degrees in the direction indicated by the arrow 59 (FIG. 4), the inner shaft 8 is rotatably attached to the second shaft 27 by the arrow 53 and the arrow 5. 4, arrow 55 It is possible to make the rotation of the parent arm 24, etc. in 5 directions endlessly over 360 degrees or more. Also, the inner shaft 8 is rotated in the direction opposite to the arrows 59 (FIG. 4), and the parent arm 24 and the like are moved in the directions opposite to the arrows 53, 54, and 55. It can be rotated infinitely.

The rotation of the parent arm 24 and the like in the above can be accurately performed to a desired angle by controlling the rotation detectors and the torque input means attached to the inner shaft 8 and the outer shaft 9 described above. And with strict reproducibility. In the robot arm of the present invention, the ratio of the number of teeth of each timing pulley formed as a toothed pulley is appropriately determined in advance, and the rotation is performed under the determined tooth number ratio. By rotating the inner shaft 8 while grasping the rotation speed by the detector, the distance L (Fig. 3) from the inner / outer double shaft of the inner shaft 8 and the outer shaft 9 to the tip of the finger arm 28 is set to the desired size. The parent arm 24 and the like can be rotated by a desired angle while expanding and contracting. For example, a first timing pulley 29, a second timing pulley 23, a third timing pulley 30, a fourth timing pulley 32, and a fifth timing pulley If the ratio of the number of teeth between the one 34 and the sixth evening pulley 135 is set to 1: 2: 2: 1: 1: 2, the rotation of the parent arm 24 shown in FIG. The relationship of 0p21 / 2 Sc = Sf is established between the angle 6> p, the rotation angle Sc of the child arm 25, and the rotation angle Θf of the finger arm 28. Becomes

 In this way, if the ratio of the number of teeth of each timing tree and the length of the parent arm 24 and the like are appropriately determined in advance, the number of rotations of the inner shaft 8 will increase the number of rotations of the finger arm 28. It is possible to plan in advance where the tip of the can be moved.

 On the other hand, in the robot arm of the present invention, the distance L (FIG. 3) from the inner / outer double shaft of the inner shaft 8 and the outer shaft 9 which is the center of the rotation of the robot arm to the tip of the finger arm 28 is extended and contracted. Instead, when rotating the parent arm 24 etc., control the stepping spiders 17 and 18 to synchronize the inner shaft 8 and outer shaft 9 to rotate at the same angular velocity. That is, the inner shaft 8 and the outer shaft 9 are fixed so that the first timing pulley 29 fixed to the inner shaft 8 and the second timing pulley 23 fixed to the outer shaft 9 do not relatively change with each other. Axis 9 is rotated synchronously at the same angular velocity.

 For example, the inner shaft 8 and the outer shaft 9 are synchronized and rotated at the same angular velocity in the directions indicated by arrows 59 (FIG. 4).

 Thus, the third timing pulley 30 and the fourth timing pulley 1 rotatably mounted on the first shaft 26 fixedly mounted on the distal end side of the parent arm 24 so as to be rotatable. 3 2, the first timing belt 31 and the second timing belt 33 are provided with the first timing pulley 29 and the second timing pulley 23 so as not to be relatively displaced from each other. The third and fourth timing pulleys 30 and 32 try to rotate (rotate) in the direction of arrow 59 (Fig. 4) around the first shaft 26, respectively. .

Here, the first, second, third and fourth timing pulleys 29, 23, 30 and 32 formed as toothed pulleys have the above-described ratio of the number of teeth. 3, the fourth timing pulley 30 and 32, the first and second evening around the first shaft 26 The first and second timing belts 31 and 33 are kept in tension while rotating (rotating) in the same direction as the imming pulleys 29 and 23, that is, in the direction of arrow 59 (Fig. 4). As it rotates, it rotates in the direction of arrow 53 (Fig. 4) with the inner and outer dual axes consisting of the inner shaft 8 and the outer shaft 9 as the center of rotation.

 Along with this, the first shaft 26 also revolves in the direction of the arrow 53 (FIG. 4) with the outer shaft 9 as the center of rotation, so that the first shaft 26 is fixedly erected on the tip side. The parent arm 24 also rotates around the outer shaft 9 in the direction of arrow 53 (FIG. 4).

 Here, as described above, the third evening imaging tree 30 to which the base end side of the child arm 25 is fixed is rotated around the first shaft 26 in the direction indicated by arrow 53 (FIG. 4). The child arm 25 also shows an arrow around the first shaft 26 in accordance with the rotation of the third timing pulley 30 around the first shaft 26 as the center of rotation. 5 Rotate in three directions (Fig. 4). At this time, the first timing pulley 29, the second timing pulley 23, the third timing pulley 30, the fourth timing pulley 32, and the fifth timing pulley 3 As described above, there is a tooth ratio of 1: 2: 2: 1: 1: 2 between the fourth and sixth timing trees 35, and the fifth evening pulley 34 Rotates in the direction of arrow 53 (FIG. 4) together with the first shaft 26 without rotating, and the sixth timing pulley 135 is fixed to the tip of the slave arm 25. Since the child arm 25 can rotate around the second axis 27 in the direction indicated by the arrow 53 around the first axis 26 of the child arm 25 described above (FIG. 4), the rotation between the parent arm 24 and The movement is performed in the direction indicated by arrow 53 (that is, in the direction opposite to arrow 54) (FIG. 4) in synchronization with the parent arm 24 without causing relative displacement.

At this time, a finger arm 28 whose base end is fixed to a sixth timing pulley 35 rotatably attached to a second shaft 27 fixed to the distal end of the slave arm 25 This is because the sixth timing pulley 135 is rotating (rotating) around the second shaft 27 in the direction indicated by arrow 53 (that is, the direction opposite to the direction indicated by arrow 54) (FIG. 4). According to the rotation, the shaft rotates about the second axis 27 in the direction indicated by the arrow 55 (that is, in the same direction as the arrow 53) (FIG. 4). The rotation of the finger arm 28 in the direction of the arrow 55 (FIG. 4) about the second axis 27 also depends on the tooth ratio between the respective timing pulleys. Same as child arm 25 without causing relative displacement In the expected direction, it will be performed in the direction of arrow 55 (that is, in the same direction as arrow 53 and in the opposite direction of arrow 54) (Fig. 4).

 Therefore, the child arm 25 and the finger arm 28 both move the outer shaft 9 together with the rotation of the parent arm 24 in the direction of arrow 53 (FIG. 4) with the outer shaft 9 as the center of rotation. As the center of rotation, it rotates in the direction indicated by the arrow 53 (Fig. 4).

 That is, in view of the displacement of each arm during this rotation, the child arm 25 is relative to the parent arm 24, and the finger arm 28 is relative to the child arm 25. Without displacement, the whole unit rotates in the direction of arrow 53 (Fig. 4).

 In this way, the distance L (Fig. 3) from the inner / outer dual axis of the inner shaft 8 and outer shaft 9, which is the center of the rotation of the robot arm, to the tip of the finger arm 28 does not expand or contract, and the parent arm 24 The finger arm 28 to the finger arm 28 rotate in the direction indicated by the arrow 53 (FIG. 4) without causing relative displacement with each other.

 The distance L (Fig. 3) from the inner / outer double shaft of the inner shaft 8 and outer shaft 9, which is the center of the rotational movement of the robot arm, to the tip of the finger arm 28 is not expanded or contracted. The following tooth ratios are maintained between the timing pulleys so that the rotation from 24 to the finger arm 28 can be integrally performed without causing relative displacement between them as described above. Need to be.

 That is, the ratio of the number of teeth between the first evening pulley 29 and the second evening pulley 23 is equal to the number of teeth between the third timing pulley 30 and the fourth timing pulley 32. The ratio of the number of teeth between the third evening imaging pulley 30 and the fourth evening imaging pulley 32 is the inverse of the number ratio, and the fifth evening imaging pulley 34 and the sixth evening It is necessary to set the gear ratio between the timing pulleys so as to be the reciprocal of the gear ratio between each pulley 35.

In the robot arm of the present invention, as described above, the parent arm 24 or the like is arbitrarily raised or lowered in the upward or downward direction, the parent arm 24 or the like is rotated infinitely by 360 degrees or more, or the robot arm rotates. Even when the distance L (Fig. 3) from the inner / outer double shaft of the inner shaft 8 and outer shaft 9 that is the center of the Of the workpiece etc. by the suction beak 4 9 Can do the work. This is made possible by employing the structure and configuration described below.

 That is, the inner shaft 8 is formed in a hollow cylindrical shape whose upper and lower ends are closed, and as shown in FIG. 1, the upper end side of the hollow portion of the inner shaft 8 is a ventilation portion in the parent arm 24. Vent holes 45, vents provided on first shaft 26, vents 47 as vents in child arm 25, vents provided on second shaft 27, finger arms The finger arm 28 communicates with the suction beak 49 on the distal end side through a ventilation hole 48 which is a ventilation part in the inside 28.

 Here, the ventilation section provided in the first shaft 26 is configured as shown in FIG. That is, a stopper cylinder 58 provided with an annular ventilation hole 46 is fitted to the first shaft 26, and a ventilation hole 45 in the parent arm 24 and a ventilation hole 4 in the child arm 25. 7 are each configured to communicate with the annular vent hole 46. As a result, even if the child arm 25 rotates more than 360 degrees around the first shaft 26, the ventilation hole 47 in the child arm 25 always remains in the annular shape in the stopper tube 58. The parent arm 24 can communicate with the ventilation hole 45 in the parent arm 24 through the ventilation hole 46.

 Although not shown, a connection between the upper end side of the hollow portion of the inner shaft 8 and the air hole 45 in the parent arm 24 is provided on the second shaft 27 from the air hole 47 of the child arm 25. The connection of the finger arm 28 to the ventilation hole 48 through the ventilation portion can also adopt the configuration of the ventilation portion provided on the first shaft 26 shown in FIG.

 On the other hand, at the lower end side of the hollow portion of the inner shaft 8, as shown in FIG. 1, a suction pipe 7 extending to a predetermined length vertically in the hollow portion of the inner shaft 8 penetrates the elevating plate 6. The intake pipe 4 is connected to 4.

 The predetermined length at which the upper end opening of the suction pipe 7 extends vertically in the hollow portion of the inner shaft 8 needs to be at least longer than the above-described vertical movement of the elevating plate 6. If the length at which the upper end opening of the suction pipe 7 extends vertically in the hollow portion of the inner shaft 8 is set as described above, the vertical movement of the lifting plate 6, that is, the vertical movement of the parent arm 24, etc. The upper end opening of the suction pipe 7 can always be present in the hollow portion of the inner shaft 8 even in the directional movement.

With the above configuration, the suction beak 49 on the distal end side of the finger arm 28 can be At any time during the elevating operation and rotating operation of the system 24, etc., it is connected to the intake pipe 44, and the base end of the intake pipe 44 is connected to the gas supply / discharge means. By sucking and discharging the work, the work can be sucked and released by the suction beak 49. In the ventilation section provided on the first shaft 26 and the like, the ingress of dust and leakage of ventilation can be prevented by sealing the bearing with a mechanical seal or a magnetic seal.

 As described above, the preferred embodiments of the present invention have been described with reference to the accompanying drawings. However, the present invention is not limited to these embodiments, and various modifications can be made within the scope of the invention described in the claims. is there.

Claims

The scope of the claims Claim 1  An inner / outer double shaft composed of an inner shaft and an outer shaft each having a lower end rotatably attached to a lifting plate, and a parent having a base end rotatably attached to the upper end of the outer shaft. An arm, a child arm having a base end rotatably attached to a first shaft erected on the distal end side of the parent arm, and a second arm erected on the distal end side of the child arm. The inner shaft and the outer shaft are provided with a rotation detector and a rotation force input means, respectively, and a finger end is rotatably mounted on the base end side. The first timing pulley and the second timing pulley are respectively fixed, and the first timing pulley and the second timing pulley are rotatably mounted on the first shaft. The timing sequence is set up and down A third timing tree and a fourth timing tree that are combined with each other by a first timing belt and a second timing belt, and a base end side of the child arm is By being fixed to the upper end side of the third evening imaging wheel, it is rotatably attached to the first shaft, and the fifth shaft is further fixed to the first shaft. The timing pulley is connected to a sixth timing pulley rotatably attached to a second shaft erected on the distal end side of the slave arm by a third timing belt. A robot arm rotatably attached to the second shaft by being fixed to the sixth timing pulley, wherein the first, second, third, fourth, fifth, and The sixth timing pulley is formed as a toothed pulley, and a predetermined tooth ratio is defined between the number of teeth of each timing pulley. Claim 2 A suction beak is provided on the distal end side of the finger arm, and the inner shaft is formed in a hollow cylindrical shape with upper and lower ends closed, and the upper end side of the hollow portion of the inner shaft is provided with a ventilation portion in the parent arm, It communicates with the suction beak on the tip end side of the finger arm through the ventilation part provided on the shaft, the ventilation part in the child arm, the ventilation part provided on the second shaft, and the ventilation part in the finger arm. The lower end side of the hollow portion of the inner shaft has a base end side for gas supply / discharge means. 2. The robot arm according to claim 1, wherein an opening on the distal end side of the suction tube to which is connected is inserted over a predetermined vertical height.