JPS6190888A - Arm device for industrial robot - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an arm device for an industrial robot that performs welding or assembly, and is designed to prevent the arm device from being damaged by the impact even if the arm device collides with a foreign object. This invention relates to an arm device for an industrial robot 7).

[Conventional technology]

Conventional 2 For example, as shown in Japanese Unexamined Patent Publication No. 58-16 (1094), when excessive torque is applied to the robot arm, the robot arm can freely rotate in at least one of the horizontal rotation direction and the vertical rotation direction. change the state,
There is a robot device that avoids excessive external force by entering the free rotation state.

However, in such conventional devices.

The mechanism for generating a free rotation state in the horizontal rotation direction and the mechanism for generating a free rotation state in the vertical rotation direction must be provided in separate positions, making the configuration of the device complicated and large, resulting in increased manufacturing costs. There was this inconvenience.

[Problem that the invention seeks to solve]

The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a robot arm device having a simple structure and a compact impact avoidance mechanism.

Furthermore, it is an object of the present invention to enable the impact avoidance mechanism to have a large avoidance range when avoiding impact, thereby making it possible to more effectively avoid impact and prevent damage.

[Means for solving problems]

An arm device for an industrial robot according to the present invention.

An avoidance mechanism that performs avoidance operations against abnormal external forces,
The housing is connected and fixed to the arm and has a plurality of protrusions at a portion remote from the arm.

a housing having an opening formed between the protrusions;
A movable member housed in the housing so as to be able to rotate horizontally and vertically by the protruding portion; applying a predetermined connecting force between the housing and the movable member; and a coupling mechanism that prevents relative rotational movement between the housing and the movable member during normal times and provides relative rotational movement between the housing and the movable member when the abnormal external force occurs. The avoidance mechanism and the operating mechanism are connected by a connecting shaft that is sufficiently thinner than the width of the opening between the protrusions.

[Effect]

In this invention, since the part that stores and holds the 0]' moving member is constituted by the protruding parts, the open part formed between these protruding parts can also be used for avoidance action. , thereby making it possible to greatly expand the range of avoidance movement, and making it possible to perform multiple movements over an angle of 90° or more from the normal position.

Furthermore, the avoidance mechanism is composed of a housing having a protruding portion and a movable member housed inside the housing, and can perform avoidance operation in all directions by means of one relatively displaceable member called the movable member. Therefore, the first avoidance operation mechanism is simplified.

[Embodiments of the invention]

Figures 1 to 6 all relate to embodiments of the present invention, and in Figure 1, the base body (1) of the robot is provided with a support (2) on its upper part. (2)
A rotary drive shaft (3) is rotatably provided in the. The first arm (4) is connected to the upper end of its drive shaft (3) and rotates in a horizontal plane according to the drive shaft (310 rotational movement kh (motion is imparted by a built-in electric motor, not shown). do.

A rotary drive shaft (5) is provided at the tip of the first arm (4), and a second arm (6) is provided at the lower end of this drive shaft (5).
are connected, and the drive shaft (5) is connected to the first arm (4).
) rotates in the horizontal plane according to the rotational movement of

A rotary drive shaft (7) is provided at the tip of the second arm (5), and a shock avoidance mechanism (8), which will be described later, is connected to the lower end of the second arm (5). ) The whole unit rotates in conjunction with each other.

An operation mechanism Oυ having a pair of claws (101Q) for gripping the article (9) is connected to the lower part of the impact avoidance mechanism (8). 2 In normal times, the drive shaft (7) is connected to the drive shaft (7) via the impact avoidance mechanism (8). )
It rotates in a horizontal plane according to the rotational movement of.

Figures 2 and 3 show details of the above-mentioned impact avoidance mechanism (8), in which a housing (811) is connected to the drive shaft (7), and the housing υ is interlocked with the rotation of the drive shaft (7). Rotates...Using (At the bottom of 81J, there are three m-shaped curved protrusions 182111121 arranged at equal intervals.

housing! 811 inner surface and protrusion t82) 182
A spherical space is formed inside by the inner surface of 111121. In this spherical space, there is 1
A spherical lock is accommodated and held so that it can rotate once. The spherical frame has a protrusion (Y) (corresponding to the connection mechanism (8A) provided on each of the 8 ribs, a concave tiffil table).
i+ is formed.

The coupling mechanism (circle) was placed in a hole that horizontally penetrates the protrusion (821).The adjustment screw (84a) (84a
) (84a).

Coil spring (84bX84bX84b), ff
l gold (84c) (84c) (84C), ball (84
d) (84d) (84d). A connecting force is applied by this connecting mechanism (841).

The rotational movement of the housing υ is transmitted to the sphere l83).

The connection force is adjusted by an adjustment screw (84a).

An open part is formed between each of the above-mentioned protrusions (821 (821I821), and the lower edge surface of this open part (housing +81) is located above the center of rotation of the sphere play. ing.

The operating device 1J77 (111 is connected and fixed to the sphere link by operation @(lla), and according to the rotation of the 1 sphere &),
The lever (llb) rotates in a horizontal plane. Axis (l
The thickness of la) is sufficiently thinner than the width of the opening between the protrusions vJ (821), and allows a sufficient amount of movement within the opening.

2 Although not shown, the claw υυ1 (
10) to perform gripping and release operations of the m body (9).

To explain the operation below, the operating mechanism circle is connected to the drive shaft (7
) and/or during horizontal movement according to the rotation of the second arm (6).

If it collides with some kind of proboscis, the operating mechanism (11)
will stop moving at that position. However, drive = (71
and/or because the second arm (6) tries to continue moving, the pole (S4d) of the suppression mechanism (841) resists the force of the coil spring (84b) and escapes from the recess (85) of the spherical lock, After that, the operation mechanism (111) and Uzing (8I)
It becomes possible to move freely relative to each other regardless of the rotation of the robot, and as shown in Figure 4, it can be avoided in the vertical direction, or it can be avoided in the horizontal direction from the state shown in Figure 5 to the state shown in Figure 6. When activated, it prevents the occurrence of shock due to collision and damage caused by it.

Avoidance operations are performed not only in the vertical and horizontal directions as described above, but also in diagonal directions, which are a combination of movements in both directions, and it is possible to perform avoidance operations in any direction.

In this invention, the holding portion of the two spheres □ is the protruding portion f821.
+82) (821), the opening formed between these protrusions (82I (8211, 8'll) is also used for the avoidance operation, and the avoidance operation range of the operation mechanism Oυ is As shown in FIG. 4, it can be expanded and the avoidance operation can be performed over an angle of 90 degrees or more from the normal position.

In addition, the lower edge of the housing (811) and the outer surface of the protruding portion (ribs! 821 + 821) are each formed with an inclined surface so as to form an open portion that gradually widens outward. The rotatable range of the operation mechanism Qll (ie, operation) lla is expanded.

Furthermore, the 1 avoidance operation mechanism (8) has a protruding portion +821 [F]
2) (It is composed of a housing (81) having ribs and a sphere □□□ housed inside the housing (81), and has two spheres (
Avoidance operation can be performed in all directions using a single relatively displaceable member 831. Therefore, the first avoidance operation mechanism can be simplified, miniaturized, and manufactured at low cost.

In the above embodiments, the arm of the robot rotates in a horizontal plane.

The present invention can be applied even if the arm moves in the vertical direction or in both horizontal and vertical directions.

1, the number of protrusions (821) is not limited to three, but may be two or four; the number may be selected as appropriate depending on the application.

Furthermore, although the pressing mechanism f&IJ applies a pressing force to one spherical field from the horizontal direction, the pressing force is not limited to the horizontal direction, and there is no problem in applying the pressing force from diagonally up and down directions.

〔Effect of the invention〕

In this invention, the movable member storage and holding portion is one of the parts of the abnormal external force avoidance mechanism.

Since it is composed of protrusions, the openings formed between these protrusions can also be used for avoidance operation, thereby greatly expanding the range of avoidance operation.

Further, the first avoidance operation mechanism is composed of a housing having a protrusion and a movable member housed inside the housing, and can perform avoidance operation in all directions by one relatively displaceable member called the movable member. Therefore, the second avoidance operation mechanism can be simplified, downsized, and manufactured at low cost.

[Brief explanation of drawings]

FIG. 1 is a front view showing the overall configuration of an industrial robot to which the present invention can be applied. FIG. 2 is a front view showing an avoidance mechanism and an operating section provided at the tip of the arm of the robot in FIG. 1. 3 is a partially cutaway front view showing the internal configuration of the avoidance mechanism shown in FIG. 2; FIG. FIG. 4 is a front view showing the turning movement of the operating section in the vertical plane by the avoidance movement mechanism. The gs diagram is a bottom view showing the avoidance mechanism and the operating section at the tip of the arm as seen from below. FIG. 6 is a bottom view showing a state in which the operating section has performed an avoidance operation in a horizontal plane. In the drawings, parts indicated by the same reference numerals indicate the same or similar parts. +41 (6+...Arm, (8)...Escape operation mechanism, (a++...Housing, Su...Protrusion, field...Sphere ('OT moving member), (d...Connection) Mechanism, 0
1)...Operating mechanism, (lla)...Connection shaft.

Claims (10)

[Claims] (1) An arm that moves in a commanded direction; An operating mechanism that is connected to a part of this arm and performs the commanded work; An abnormal external force is applied to the operating mechanism that is provided between the arm and the operating mechanism. an avoidance operation mechanism that moves the operating mechanism relative to the arm to perform an external force avoidance operation when a force is applied; the avoidance operation mechanism includes: a) a housing connected and fixed to the arm;
a housing having a plurality of protrusions at a portion remote from the arm, with openings formed between the protrusions; b) horizontal rotation and vertical rotation within the housing by the protrusions; c) A predetermined connection force is applied between the housing and the movable member so that the housing and the movable member can move together, and the relative rotational movement between the housing and the movable member is normally controlled. and a coupling mechanism that provides relative rotational movement between the housing and the movable member when the abnormal external force occurs, and the avoidance operation mechanism and the operation mechanism include:
An arm device for an industrial robot, characterized in that the arm device is connected by a connecting shaft that is sufficiently thinner than the width of the opening between the protrusions. (2) In claim 1, the movable member is an arm of an industrial robot that is formed of a sphere and is held rotatably both horizontally and vertically within the housing. Device. (3) The arm device for an industrial robot according to claim 2, wherein the housing and the protrusion form a spherical holding surface therein. (4) In claim 1, the connection mechanism is disposed on the plurality of protrusions, and the protrusion is located on the side of the movable member, so that An industrial robot arm device that applies connecting force from the direction. (5) In claim 1, the coupling mechanism applies a pressing force to the movable member from a plurality of lateral directions of the movable member, thereby causing the movable member to rotate relative to the housing. An arm device for industrial robots that prevents (6) In claim 5, the movable member is composed of a sphere, and a recess is formed on the outer surface of the sphere at a position corresponding to the connection mechanism, and the connection mechanism is arranged in the recess. The movable member has a member that is elastically pressed so as to move forward and backward, and when the abnormal external force occurs, the pressing member moves back and leaves the recess, so that the movable member can rotate relative to the housing. An arm device for industrial robots. (7) The arm device for an industrial robot according to claim 6, wherein the pressing member of the coupling mechanism is constituted by a ball to which a predetermined pressure is always applied in the direction of the sphere by an elastic body. (8) In claim 7, the pressure of the elastic body against the ball is increased or decreased by variable adjustment of the amount of elastic deformation of the elastic body by an adjustment screw provided in the housing. arm device. (9) In claim 1, an edge of the open portion formed between the protrusions on the arm side is located at a position closer to the arm side than the center of rotation of the movable member. industrial robot arm device. (10) In claim 1, the edge surfaces of the openings formed between the protrusions are all sloped surfaces that widen outward from the housing. Robot arm device.