JP3230090B2 - Robot arm - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a robot arm having a finger arm provided with a suction beak on the distal end side, capable of performing a rotary motion about a rotation axis and vertically moving up and down. It concerns a possible robot arm. In particular, the present invention provides a robot arm as described above, which can rotate 360 degrees or more around the rotation axis any number of times, and the distance from the rotation axis to the suction beak is expandable and contractable, The present invention relates to a robot arm capable of performing a suction operation of a work by the suction beak at any position where an infinite rotation operation or a lifting operation is performed.

BACKGROUND ART An invention related to a rotating device of an articulated robot has been conventionally proposed. For example, Japanese Patent Application Laid-Open No. 61-2736.
No. 03 etc. Further, there has been proposed a robot rotating mechanism capable of rotating 360 degrees or more with a configuration having a mechanical stopper (Japanese Patent Application Laid-Open No. Sho 61-2).
No. 73603). Furthermore, there has been proposed 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. 4-275894).

However, the arm can be rotated 360 times or more around the rotation axis, and the distance from the rotation axis to the suction beak on the finger arm tip side can be expanded and contracted, so that the arm can be rotated infinitely as described above. A robot arm capable of performing an operation of sucking a work or the like by the suction beak at any position where the operation is performed or at any position of the elevating operation of the arm has not been proposed so far.

DISCLOSURE OF THE INVENTION According to the present invention, a parent arm, a child arm, and the like constituting a robot arm can be rotated indefinitely by 360 degrees or more, and further provided on the distal end side of the robot arm from the rotation center of the robot arm. It is an object of the present invention to provide a robot arm that can arbitrarily expand and contract the distance to a finger arm and that can freely adjust the vertical height of the robot arm.

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

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 having a lower end rotatably attached to an elevating plate, and a base end on the upper end side of the outer shaft. A parent arm whose side is rotatably mounted,
A base arm of the first shaft erected on the distal end of the parent arm is rotatably mounted on the child arm, and a base end of the second shaft erected on the distal end of the child arm is rotatable. And a finger arm rotatably mounted.

The inner shaft and the outer shaft are provided with a rotation detector and a rotational 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 attached to the first shaft, and are a third timing pulley and a fourth timing pulley that are vertically combined.
And the first and second timing belts are connected to each other by a first timing belt, and the base end of the slave arm is fixed to the upper end of the third timing pulley. It is rotatably mounted on a shaft.

Further, a fifth timing pulley is further fixed to the first shaft, and the fifth timing pulley is rotatably attached to a second shaft provided upright on the distal end side of the child arm. The sixth timing pulley is connected to a sixth timing pulley by a third timing belt, and the finger arm is rotatably attached to the second shaft by being fixed to the sixth timing pulley.

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 gear ratio is defined between the number of gears of the pulley.

By adopting the above configuration, the robot arm of the present invention can rotate infinitely around the rotation axis by 360 degrees or more, and can expand and contract the distance from the rotation center to the finger arm arbitrarily. Can be. In addition, the infinite rotation can be performed in either the forward or reverse direction, so that the parent arm or the like can be moved and rotated with a minimum amount of rotation, and the desired rotation can be performed in a short time. It can be moved and rotated to the position, and the work efficiency in the work using the robot can be improved.

Another robot arm proposed by the present invention is the robot arm described above, further comprising:
The inner shaft is formed in a hollow cylindrical shape whose upper and lower ends are closed, and the upper end of the hollow portion of the inner shaft is provided in the ventilation portion in the parent arm and the first shaft. Through a ventilation portion provided in the child arm, a ventilation portion provided in the second arm, a ventilation portion provided in the second shaft, and a ventilation portion provided in the finger arm. A robot arm in which a distal end opening of a suction pipe connected to a base end side of a gas supply / discharge unit is inserted at a predetermined lower end side at a lower end side.

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 rotation center of the robot arm to the finger arm is arbitrarily expanded or contracted. And
At any position where the height of the robot arm is arbitrarily raised and lowered in the vertical direction, an operation of sucking a work or the like by the suction beak provided on the finger arm can be performed.

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, the ball screw 4 which is rotatably installed upright between the lower plate 2 and the upper plate 3 of the machine frame 1 is fixed to one side (left side in FIG. 1) of the elevating plate 6. The cylinder nut 5 is screwed.

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

On the other side (the right side in FIG. 1) of the lifting plate 6, the lower end side of the inner shaft 8 of the robot arm is rotatably mounted. An outer shaft 9 of a 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 lower ends of the inner shaft 8 and the outer shaft 9 constituting the inner and outer dual shafts of the robot arm are rotatably attached to the elevating plate 6, respectively.

The basic configuration of the robot arm of the present invention includes a parent arm 24 whose base end is rotatably attached to the upper end of the outer shaft 9 described above, and a standing arm standing on the distal end of the parent arm 24. The child arm 25 whose base end is rotatably attached to the first shaft 26, and the base end is rotatably attached to the second shaft 27 erected on the distal end of the child arm 25. And a finger arm 28 having a suction beak 49 on the tip side.

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

As shown in FIG. 2, timing pulleys 19 and 20 fixed to output shafts of stepping motors 17 and 18 mounted on the elevating plate 6 and lower end portions of the inner shaft 8 and the outer shaft 9 are provided. The fixed timing pulleys 11 and 10 are connected to the timing belt 2 respectively.
1 and 22, these constitute a rotational force input means attached to the inner shaft 8 and the outer shaft 9.

A first timing pulley 29 and a second timing pulley 23 are provided on the upper end sides of the inner shaft 8 and the outer shaft 9, respectively.
Are fixed respectively (FIGS. 1 and 5). First timing pulley 29, second timing pulley 23
Is a timing pulley rotatably mounted on a first shaft 26 fixedly provided on the distal end side of the parent arm 24, and is a third timing pulley 30, which is vertically assembled, A timing pulley 32,
They are connected by a first timing belt 31 and a second timing belt 33 (FIGS. 1 and 5).
It is preferable to arrange a guide pulley 56 between the first timing belt 31 and the second timing belt 33 as shown in FIG.
6 may not be provided.

The child arm 25 is rotatably attached to the first shaft 26 by fixing the base end side to the upper end side of the third timing pulley 30.

As shown in FIGS. 1 and 5, the first shaft 26 further includes a fifth
Is fixed, and the fifth pulley 34 is fixed.
The timing pulley 34 is connected by a third timing belt 36 to a sixth timing pulley 35 rotatably mounted on a second shaft 27 fixedly provided on the distal end side of the child arm 25. Have been. It is preferable to arrange the 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.

Further, the finger arm 28 having the suction beak 49 on the distal end side is rotatably attached to the second shaft 27 by fixing the base end side to the sixth timing pulley 35.

The parent arm 24 in the robot arm of this embodiment,
The child arm 25 and the finger arm 28 (hereinafter, collectively referred to as “parent arm 24
And the like) is performed as follows.

By driving the stepping motor 38, the ball screw 4
When the ball screw 4 is rotated by applying a rotational force to the cylinder nut 5, the cylinder nut 5
It moves up and down in three directions (FIG. 1). As a result, the elevating plate 6 and the inner shaft 8 and the outer shaft 9 whose lower ends are rotatably mounted thereon also move 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 operation of elevating the parent arm 24 and the like is performed.

As shown in FIG. 1, the stepping motor 38 is provided with a sensor dog 51 and a photo sensor 52. The sensor dog 51 and the photo sensor 52 detect the rotation of the stepping motor 38 and move the parent arm 24 and the like in a desired vertical direction. Can be made.

Further, the operation for extending and contracting the distance L (FIG. 3) from the inner and outer double shafts consisting of the inner shaft 8 and the outer shaft 9 to the tip of the finger arm 28 is performed as follows.

The stepping motor 17 is stopped, and the outer shaft 9 is not rotated. On the other hand, by operating the stepping motor 18, only the inner shaft 8 is, for example, shown in FIG.
Rotate in the direction of arrow 59. The first timing pulley 29 fixed to the upper end side of the inner shaft 8 tends to rotate in the direction indicated by the arrow 59 as the inner shaft 8 rotates, and this rotational force is transmitted through the first timing belt 31 to the third timing pulley 29. Attempt to be transmitted to timing pulley 30.

Therefore, the third timing pulley 30 and the fourth timing pulley 32 formed integrally therewith are:
Similarly, it is about to rotate in the direction of arrow 59 about the first shaft 26.

However, the fourth timing pulley 32 is fixed to the upper end side of the outer shaft 9 which is prevented from rotating.
The third timing pulley 30 and the fourth timing pulley 32 are connected to the first pulley 23 and the second timing belt 33, respectively.
Cannot be rotated in the direction indicated by the arrow 59 around the center.

Therefore, the third and fourth timing pulleys 30, 32
While the tension state of the first and second timing belts 31 and 33 is maintained, the inner shaft 8 and the first timing pulley 2
Rotation (rotation) in the direction of arrow 54 (FIGS. 3 and 4) about the first shaft 26 in response to the rotational movement in the direction of arrow 59 in FIG.
While rotating (revolving) in the direction of arrow 53 with the outer shaft 9 as the center of rotation. Accordingly, the first shaft 2
6 also rotates (revolves) in the direction of the arrow 53 with the outer shaft 9 as the center of rotation, so that the parent arm 24, on which the first shaft 26 is fixedly mounted on the distal end side, also rotates the outer shaft 9. Rotate in the direction of arrow 53 (FIG. 4) as the center of.

On the other hand, the child arm 25 is rotatably attached to the first shaft 26 by fixing its base end side to the upper end side of the third timing pulley 30.
With the rotation (rotation) of the third timing pulley 30 in the direction indicated by the arrow 54 (FIGS. 3 and 4) around the first shaft 26 of the third timing pulley 30, similarly, the arrow 5 is displayed about the first shaft 26 as well.
It rotates in four directions (FIGS. 3 and 4).

The second fixedly erected on the distal end side of the slave arm 25
A sixth timing pulley 35 is rotatably attached to the shaft 27.
5 is connected to a fifth timing pulley 34 fixed to the first shaft 26 and a third timing belt 36. 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 indicated by an arrow 53 (FIG. 4).
Since the first shaft 26 is fixed to the parent arm 24 and stands upright, it does not rotate. Therefore, the sixth timing pulley 35 rotatably attached to the second shaft 27 is
The second arm 27 is fixed to the distal end thereof. The child arm 25 rotates about the first shaft 26 in the direction of arrow 54 (FIG. 3) and the first shaft to which the fifth timing pulley 34 is fixed. With the rotation of 26 in the direction of arrow 53 (FIG. 3), it rotates (rotates) in the direction of arrow 55 (FIGS. 3 and 4).

Therefore, by being fixed to the sixth timing pulley 35, the finger arm 28 rotatably attached to the second shaft 27 also rotates in the direction of arrow 55 (FIGS. 3 and 4). Become.

By the above-described movement, the distance L (FIG. 3) from the inner and outer dual axes of the inner shaft 8 and the outer shaft 9, which are the center of the rotation operation of the robot arm of the present invention, to the tip of the finger arm 28 is expanded and contracted. .

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 a first shaft fixed to the distal end of the parent arm 24. 26
Fixed to the upper end side of the third timing pulley 30 rotatably mounted on the
A sixth end is rotatably attached to the shaft 26, and a base end of the finger arm 28 is rotatably attached to a second shaft 27 fixed to the front end of the slave arm 25.
Is fixed to the upper end side of the timing pulley 35, and is rotatably attached to the second shaft 27. Therefore, by rotating the inner shaft 8 in the direction of arrow 59 (FIG. 4) by 360 degrees or more. , Arrow 53, arrow 54, arrow 5
The rotation of the parent arm 24 and the like in five directions can be performed indefinitely over 360 degrees or more. In addition, the inner shaft 8 is rotated in the direction opposite to the arrow 59 (FIG. 4) so that the parent arm 24 is rotated.
And the like can be rotated infinitely in the directions opposite to the arrows 53, 54, and 55, respectively.

The rotation of the parent arm 24 and the like in the above can be accurately and strictly controlled to a desired angle by controlling the rotation detectors and the rotation force input means respectively attached to the inner shaft 8 and the outer shaft 9 described above. With high 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 detector detects the ratio under the determined tooth ratio. By rotating the inner shaft 8 while grasping the rotation speed, the inner shaft 8 and the outer shaft 9 are rotated.
The parent arm 24 and the like can be rotated by a desired angle while the distance L (FIG. 3) from the inner / outer double shaft to the tip of the finger arm 28 is expanded and contracted to a desired size.

For example, the first timing pulley 29, the second timing pulley 23, and the third timing pulley 3
0, the fourth timing pulley 32, the fifth timing pulley 34, and the sixth timing pulley 35, if the tooth number ratio is set to 1: 2: 2: 1: 1: 2, FIG. The relationship of θp = １ ／ θc = θf is established between the rotation angle θp of the parent arm 24, the rotation angle θc of the child arm 25, and the rotation angle θf of the finger arm 28 shown in FIG. Become.

In this way, if the ratio of the number of teeth of each timing pulley and the length of the parent arm 24 and the like are appropriately determined in advance, the rotation of the inner shaft 8 can move the tip of the finger arm 28 to any position. Or can be scheduled in advance.

On the other hand, in the robot arm of the present invention, the distance L (FIG. 3) from the inner and outer double axes of the inner shaft 8 and the outer shaft 9 which are the center of the rotation operation of the robot arm to the tip of the finger arm 28 is not expanded or contracted. When the parent arm 24 and the like are rotated, the stepping motors 17 and 18 are controlled to synchronize and rotate the inner shaft 8 and the outer shaft 9 at the same angular velocity. That is, the inner shaft 8 and the outer shaft 9 are synchronized 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. And rotate at the same angular velocity.

For example, the inner shaft 8 and the outer shaft 9 are synchronously rotated in the direction of arrow 59 (FIG. 4) at the same angular velocity.

As a result, the first timing pulley 30 and the fourth timing pulley 32 that are rotatably mounted on the first shaft 26 that is fixed to the distal end side of the parent arm 24 and are erected are provided with the first timing pulley 30. Via the timing belt 31 and the second timing belt 33, the rotational force given to the first timing pulley 29 and the second timing pulley 23 so as not to be relatively displaced from each other is transmitted to the third and third timing pulleys. The fourth timing pulleys 30 and 32 rotate (rotate) around the first shaft 26 in the direction of arrow 59 (FIG. 4).
try to.

Here, the first, formed as a toothed pulley,
Second, third and fourth timing pulleys 29, 23, 3
Since 0 and 32 have the aforementioned ratio of the number of teeth, the third and fourth teeth
The timing pulleys 30 and 32 rotate around the first shaft 26 in the same direction as the first and second timing pulleys 29 and 23, that is, in the direction indicated by the arrow 59 (FIG. 4). 1. While maintaining the tensioned state of the second timing belts 31, 33, the inner and outer 2 composed of the inner shaft 8 and the outer shaft 9
It rotates in the direction indicated by the arrow 53 (FIG. 4) around the axis of rotation 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.
Arm 24 is fixedly erected on its tip side.
Also rotates around the outer shaft 9 in the direction of arrow 53 (FIG. 4).

Here, as described above, the third timing pulley 30 to which the base end side of the child arm 25 is fixed is connected to the first shaft 2
6, the child arm 25 rotates (rotates) in the direction of the arrow 53 (FIG. 4), so that the child arm 25 also rotates in accordance with the rotation of the third timing pulley 30 about the first shaft 26 as the center of rotation. It rotates around the first shaft 26 in the direction indicated by the arrow 53 (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, the fifth timing pulley 34, and the sixth timing pulley 35
And 1: 2: 2: 1: 1: 2 as described above.
The fifth timing pulley 34 rotates together with the first shaft 26 in the direction of the arrow 53 (FIG. 4) without rotating, and the sixth timing pulley 35 Since the child arm 25 can rotate around the second axis 27 fixed to the tip, the above-described rotation of the child arm 25 about the first axis 26 in the direction indicated by the arrow 53 (FIG. 4) can be performed between the child arm 25 and the parent arm 24. Without causing relative displacement, the parent arm 24
4 in the direction indicated by the arrow 53 (that is, the direction opposite to the arrow 54) (FIG. 4).

At this time, the sixth timing pulley 35 rotatably attached to the second shaft 27 fixed to the distal end of the child arm 25 has a finger arm 28 whose base end side is fixed. Since the pulley 35 rotates (rotates) about the second shaft 27 in the direction indicated by the arrow 53 (that is, the direction opposite to the arrow 54) (FIG. 4), the pulley 35 indicates the arrow about the second shaft 27 accordingly. It rotates in the 53 direction (that is, the same direction as the arrow 53) (FIG. 4). The rotation of the finger arm 28 in the direction indicated by the arrow 55 (FIG. 4) about the second shaft 27 also causes the relative displacement between the finger arm 28 and the child arm 25 to be determined from the tooth ratio between the respective timing pulleys. This is performed in the direction indicated by the arrow 55 (that is, the same direction as the arrow 53 and the opposite direction to the arrow 54) in synchronization with the child arm 25 (FIG. 4).

Accordingly, as the child arm 25 and the finger arm 28 rotate in the arrow 53 direction (FIG. 4) around the outer shaft 9 of the parent arm 24 as the center of rotation, both the child arm 25 and the finger arm 28 move in the arrow 53 direction with the outer shaft 9 as the center of rotation. (FIG. 4).

In other words, in view of the displacement of each arm during this rotation, the child arm 25 and the finger arm 28 do not cause relative displacement with respect to the parent arm 24 and the child arm 25, respectively. As a whole,
It rotates in the direction of the arrow 53 (FIG. 4).

Thus, the finger arm 28 is moved from the inner and outer dual axes of the inner shaft 8 and the outer shaft 9 which are the center of the rotation operation of the robot arm.
Distance L (FIG. 3) to the tip of
To the finger arm 28 rotate in the direction indicated by the arrow 53 (FIG. 4) without causing relative displacement with each other.

Note that 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 operation of the robot arm to the tip of the finger arm 28 is not expanded or contracted.
In order to integrally rotate the four to the finger arms 28 without causing relative displacement with each other, the following tooth ratio needs to be maintained between the timing pulleys. .

That is, the ratio of the number of teeth between the first timing pulley 29 and the second timing pulley 23 is the reciprocal of the ratio of the number of teeth between the third timing pulley 30 and the fourth timing pulley 32, and 3 timing pulley 3
The tooth number ratio between 0 and the fourth timing pulley 32 is
It is necessary to set the gear ratio between the timing pulleys so as to be the reciprocal of the gear ratio between the fifth timing pulley 34 and the sixth timing pulley 35.

In the robot arm of the present invention, as described above, the parent arm 24 and the like are arbitrarily moved up and down in the vertical direction, the parent arm 24 and the like are rotated infinitely by 360 degrees or more, and the rotation of the robot arm becomes the center of rotation. Distance L from the inner and outer dual axes of shaft 8 and outer shaft 9 to the tip of finger arm 28
Even when (FIG. 3) is expanded or contracted, the operation of sucking a work or the like by the suction beak 49 provided on the finger arm 28 can be performed. This is made possible by adopting 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. As shown in FIG. 1, the upper end of the hollow portion of the inner shaft 8 is formed as a ventilation portion in the parent arm 24. Pores 4
5. Ventilation part provided on the first shaft 26, child arm 25
The suction beak on the distal end side of the finger arm 28 through a ventilation hole 47 which is a ventilation part in the inside, a ventilation part provided in the second shaft 27 and a ventilation hole 48 which is a ventilation part in the finger arm 28. It communicates with 49.

Here, the ventilation portion provided on the first shaft 26 is provided as shown in FIG.
It 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 the ventilation hole 45 in the parent arm 24 and the ventilation hole 47 in the child arm 25 are respectively connected to the annular shape. Is formed so as to communicate with the ventilation hole 46. by this,
Even if the child arm 25 rotates 360 degrees or more around the first shaft 26, the ventilation hole 47 in the child arm 25 always
8 can be in communication with a vent 45 in the parent arm 24 via an annular vent 46.

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

On the other hand, on the lower end side of the hollow portion of the inner shaft 8, as shown in FIG. 1, a suction pipe 7 extending in the hollow portion of the inner shaft 8 over a predetermined length in the vertical direction passes through the elevating plate 6. It is connected to the intake pipe 44.

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 distance at which the elevating plate 6 moves up and down. 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 in this way, the vertical movement of the elevating plate 6, that is,
Even when the parent arm 24 or the like moves vertically, the suction tube 7
Can be present in the hollow portion of the inner shaft 8.

With the above configuration, the suction beak 49 on the distal end side of the finger arm 28 is communicated with the intake pipe 44 at any time when the raising / lowering operation and the rotation operation of the parent arm 24 and the like are performed. By connecting the base end side to a gas supply / discharge means and supplying / discharging the gas, the work can be adsorbed or separated by the adsorption beak 49.

In the ventilation portion provided on the first shaft 26 and the like described above, the invasion of dust and leakage of ventilation can be prevented by sealing the bearing portion with a mechanical seal or a magnetic seal.

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

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional view in which a part of an embodiment of the present invention is omitted. FIG. 2 is a plan view in which 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 a rotation state of a parent arm and the like is omitted and which is omitted. FIG. 5 is a partially omitted cross-sectional view illustrating a connection structure of a parent arm and the like. FIG. 6 is a partially omitted cross-sectional view showing an example of connection of ventilation holes at a central portion of the rotational movement.

Claims (2)

(57) [Claims] 1. An inner / outer double shaft comprising an inner shaft and an outer shaft each having a lower end rotatably attached to an elevating plate, and a base end rotatably attached to an upper end of the outer shaft. A parent arm, a child arm whose base end is rotatably attached to a first shaft provided on the distal end of the parent arm, and a child arm which is mounted on the distal end of the child arm. A finger arm having a base end rotatably attached to two shafts, a rotation detector and a torque input means attached to the inner shaft and the outer shaft, respectively, and A first timing pulley and a second timing pulley are fixed vertically, respectively. The first timing pulley and the second timing pulley are timing pulleys rotatably attached to the first shaft. Ah And the upper and lower third timing pulleys and the lower fourth timing pulley, which are integrally formed vertically, are connected to each other by a first timing belt and a second timing belt, respectively.
The base end side of the slave arm is fixed to the upper end side of the third timing pulley so as to be rotatably attached to a first shaft, and is further integrally formed on the first shaft with the upper and lower portions. The fifth timing pulley formed as a separate timing pulley from the third timing pulley and the fourth timing pulley is a third timing pulley, and the fourth timing pulley is a first timing pulley. The fifth timing pulley is rotatably mounted on a second shaft erected on the distal end side of the child arm. The fifth timing pulley is fixed above a position rotatably mounted on the shaft. A sixth timing pulley is connected to a third timing belt by a third timing belt, and the finger arm is connected to the sixth timing pulley. A first arm, a second arm, a third arm, a third arm, a fourth arm, a fifth arm, and a sixth arm. And a predetermined gear ratio is defined between the number of teeth of each timing pulley. 2. A finger beak is provided at a tip end side of the finger arm, and the inner shaft is formed in a hollow cylindrical shape whose upper and lower ends are closed. Via a ventilation portion, a ventilation portion provided on the first shaft, a ventilation portion in the child arm, a ventilation portion provided in the second shaft, and a ventilation portion in the finger arm, the suction beak on the finger arm tip side through the ventilation portion. Communicating with the lower end of the hollow portion of the inner shaft,
2. The robot arm according to claim 1, wherein a distal end opening of a suction tube connected to a gas supply / discharge means at a base end thereof is inserted over a predetermined vertical height.