JPH08309627A - Screw fastening device - Google Patents

Abstract

PURPOSE: To provide a screw fastening device, which can continuously and automatically perform a grinding process for grinding the surface of a screw fastening position, which follows a screw fastening position, and a filling process for filling a recessed part of the screw fastening position with putty. CONSTITUTION: A screw fastening device provided with a screw holding means 2 and a screw fastening means 3 and to be fitted to a robot hand 5 for use is provided with a surface grinding means 50 and a putty filling means 60. Both the means are arranged in the upper position of a side of the screw holding means 2, and with the movement of the robot hand 5 and a change of angle of the robot hand 5, both the means selectively contact with a screw fastening position of a material to be fastened with a screw in place of the screw holding means 2. The surface grinding means 50 has a grinding tool 53 for grinding the surface of a grinding position of a material, which is to be fastened with a screw, flat, and the putty filling means 60 has a nozzle 62 for filling a recessed part of the screw fastening position with the putty.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an assembly line for integrating a plurality of parts with screws, for screwing the fed screws directly into a screw-fastening object or into a prepared hole provided in advance. The present invention relates to a screw tightening device.

[0002]

2. Description of the Related Art As a screw tightening device of this type, it is attached to a robot hand capable of facing an arbitrary position on the surface of an object to be screwed at an arbitrary angle, and a screw holding means and a screw tightener. A screw tightening device with means was conceived. In this screw tightening device, the fed screw is held in a fixed position by the screw holding means, and the screw of the screw tightening means is moved to a predetermined position of the screw tightening target by the robot hand. Although it is to be screwed into the screw tightening target directly or into the pilot hole with the rotating shaft for tightening, the surface of the screw tightening point of the screw tightening target has a raised return part formed by the screwed screw head. A recessed portion is formed at the screw tightening point due to the biting of the screw head.

Conventionally, two post-treatments, that is, grinding and removing the raised portion on the surface of the screw tightened portion and filling the putty into the recess of the screw tightened portion, have been performed manually by the operator, so that the screw tightening operation itself is automated. Even if possible, it was not possible to rationalize the whole process including post-treatment. The present invention is a screw tightening device capable of automatically performing two post-treatments, namely, grinding removal of a raised return portion on the surface of a screw tightening place and filling putty into a recess of a screw tightening place, following a screw tightening work process. It is intended to provide.

[0004]

Means for Solving the Problems A screw tightening device of the present invention for achieving the above-mentioned object is shown by a reference numeral of an embodiment to be described later and is attached to a robot hand (5). M), which is a screw holding means (2), a screw tightening means (3), and a surface grinding means (50) for the object to be screwed (W).
And a putty filling means (60), the screw holding means (2) is
A pair of holders that are opened and closed by the opening and closing drive means (14)
(13a, 13b), the holder (13a, 13b) has a screw holding portion (15) for holding the screw (S) in a fixed position when closed,
A screw guideway for guiding the screw (S) into the screw holding part (15).
(16) is provided, and the screw tightening means (3) includes a rotary shaft (28) for screw tightening, and a rotation driving motor (29) for the rotary shaft (28).
And a lifting drive means (30) for reciprocating the rotary shaft (28) in the axial direction thereof, and the screw tightening rotary shaft (28) has the pair of holders (13a, 13a, 13b) screw holder (1
It is equipped with a screw tightening bit (38) that can engage with the head (Sa) of the screw (S) held in 5), and the surface grinding means (50) and putty filling means (60) It is arranged at the lateral upper position of the means (2), and by moving the robot hand (5) and changing the angle, the screw holding means (2) is alternatively used to screw the object to be screwed (W). The surface grinding means (50) has a grinding tool (53) that grinds the surface of the screw tightening object (W) evenly, and is put against the putty filling means (60). )
Is a nozzle (6) that fills the recess (Wb) where the screw is tightened with putty.
It is configured to have 2).

In carrying out the present invention, the grinding tool (53) of the surface grinding means (50) and the nozzle (62) of the putty filling means (60).
Is movable within a certain range in the vertical direction with respect to the surface of the screw tightening target (W) when it is in the posture of facing the screw tightening point (P), and the screw tightening target ( W) so that the surface of the screw tightening target (W) is pressed by the biasing force of the springs (56, 64) when it comes into contact with the screw tightening point (P). Can be configured.

Further, a coating means (70) can be provided side by side. This coating means (70) can be brought into contact with the screw tightening location (P) of the object to be screwed (W) only by moving the robot hand (5) and changing the angle. , A paint tool (71) for painting the surface of the screw tightening point (P) is provided.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of the present invention will be described below with reference to the accompanying drawings. As shown in FIGS. 1 and 2, a screw fastening device M according to the present invention is a screw holding device mounted on a plate-shaped frame 1. Means 2, screw tightening means 3, surface grinding means 50, putty filling means 60, and coating means 70 are provided. The plate-shaped frame 1 is connected to the robot hand 5 via the connecting means 4. The robot hand 5 is capable of rotating around the rotation axis 5a and reciprocating in the direction of the rotation axis 5a. The connecting means 4 transmits the rotation of the robot hand 5 to the frame 1, but allows movement of the frame 1 within a certain range in the direction of the robot hand rotation axis 5a, and the direction of moving the frame 1 away from the robot hand 5. A compression coil spring 6 that biases the

Explaining a concrete example of the connecting means 4, a square shaft portion 7 protruding from the tip of the robot hand in a concentric state with the rotation shaft core 5a is mounted on the plate-shaped frame 1 side through a bracket 8. The tubular member 9 is externally fitted so as to be slidable within a certain range in the direction of the rotation axis 5a, and a compression coil is applied to the rectangular tubular member 9 between the tip of the robot hand 5 and the bracket 8 facing it. The spring 6 is loosely fitted, and the square shaft 7
The bracket 8 is supported by the lower end receiving plate portion 10.
There are various conceivable concrete structures of the connecting means 4, and any structure may be used as long as it has the above-mentioned function.

The screw holding means 2 is attached to the pair of left and right bearing plates 11 attached to the plate-shaped frame 1 by means of the robot hand 5.
A pair of holders 13a and 13b that are pivotally supported by a support shaft 12 that is orthogonal to the rotation axis 5a, and an opening / closing drive means 14 that opens and closes the pair of holders 13a and 13b.
It consists of and. As shown in FIG. 5, the holders 13a and 13b include a screw holding portion 15 that holds the screw S at a fixed position in a concentric state with the rotation axis 5a of the robot hand 5 when closed, and the screw holding portion. A screw guide path 16 for guiding the screw S into the screw 15 is provided. Specifically, the screw holding portion 15 is formed by a concave groove formed inside the tip portions of the pair of holding tools 13a and 13b, and the upper end thereof has a tapered shape that widens upward so as to receive the head Sa of the screw S. Is formed in. Further, the screw guide path 16 has a holder 1 on one side so that an inner end portion thereof communicates with the screw holder 15.
A screw feeding pipe 17 is formed continuously in the outer end of the screw feeding pipe 17. As shown by a phantom line in FIG. 5, for example, one holding tool 13b may be provided with an air blowing passage 18 for blowing cleaning air into the screw holding portion 15.

The opening / closing drive means 14 is, as shown in FIG.
It is composed of a cylinder unit 19 attached to the back side of the plate-like frame 1, a movable base 20, and connecting links 21a and 21b. The movable base 20 is supported by a guide rail 22 laid on the front side of the plate-shaped frame 1 via a slide guide 23, and projects to the back side of the plate-shaped frame 1 through an elongated hole provided in the plate-shaped frame 1. Arm 2
4, the arm 24 is connected to the piston rod 19a of the cylinder unit 19 and is reciprocated by the cylinder unit 19 in the direction of the robot hand rotation axis 5a. In the cylinder unit 19, the piston rod 19a is brought into a free state by switching an electromagnetic valve (not shown) interposed in the fluid pressure supply passage to the neutral position.

The connecting links 21a and 21b are provided for each holder 1.
The free ends of the pair of arms 25a and 25b that are continuously provided obliquely outward from the upper ends of the robots 3a and 13b, and the robot hand rotation axis 5a of the bracket 26 that projects from the movable table 20.
When the movable table 20 moves in the direction of approaching the robot hand 5, the pair of holders 13a and 13b are opened around the support shaft 12 to move the movable table 20 to the robot. The pair of holders 13 a and 13 b are closed around the support shaft 12 when moved in a direction away from the hand 5. Then, when the piston rod 19a of the cylinder unit 19 is switched to the free state as described above, the screw holding portion 15 between the pair of holding tools 13a and 13b is slightly wider than the screw clamp state shown in FIG. 5A. As shown in FIG. 2A, the torsion coil spring is loosely fitted to the support shaft 12 between the bearing plate 11 and the holders 13a and 13b so as to be held in the state (the state shown in FIG. 4). 27a and 27b are interposed.

The screw tightening means 3 includes a screw tightening rotary shaft 28 concentric with the robot hand rotation shaft core 5a, a motor 29 for rotating the rotary shaft 28, and the rotary shaft 28 reciprocating in the axial direction. It is composed of a lifting drive means 30 for moving and a one-way rotation clutch 31. The lifting drive means 30 includes a cylinder unit 32 attached to the back side of the plate-shaped frame 1 and a movable base 33.
Is supported by a slide guide 34 attached to the front side of the plate-shaped frame 1 through a guide rail 35, and an arm 36 protruding to the back side of the plate-shaped frame 1 through an elongated hole provided in the plate-shaped frame 1. The arm 36 is connected to the piston rod 32a of the cylinder unit 32. The motor 29 is supported by a movable table 33, and the cylinder unit 32 reciprocates the movable table 33 in the direction of the robot hand rotation axis 5a, whereby the screw tightening rotary shaft 28 is rotated through the motor 29. It can be moved back and forth in the core direction.

As shown in FIG. 4, the screw tightening rotary shaft 28 penetrates the support shaft 12 that supports the pair of holders 13a and 13b in the diametrical direction, and also the holders 13a and 13b.
When b is closed, the tip portion is inserted into the passage 37 formed between the holders 13a and 13b, and the screw S held by the screw holding portion 15 of the pair of holders 13a and 13b is inserted into the passage 37. 3 for screw tightening that can be engaged with the head Sa of the
8 is provided. The one-way rotation clutch 31 includes a screw tightening rotary shaft 28 and the brackets 26 located on both sides thereof.
And is fitted between the rotary shaft 28 and the rotary shaft 28 so as to be slidable only in the axial direction.

Therefore, the one-way rotary clutch 31 is
When the rotary shaft 28 for screw tightening is reciprocated in the axial direction, the motor 2
The forward rotation in the screw tightening direction by 9 is allowed, but the reverse rotation is prevented. This one-way rotating clutch 31
Is a frame side portion that does not move relative to the screw tightening rotary shaft 28, for example, a movable base 33 that supports a motor 29.
It is also possible to interpose between the bracket attached to and the rotating shaft 28. In this case, it is not necessary to have a structure that allows relative movement of the rotary shaft 28 in the axial direction as described above.

The surface grinding means 50 includes a bracket 51 on the bearing plate 11 of the screw holding means 2 as shown in FIGS.
The motor (air motor or the like) 52 is mounted on the front side of the screw holding means 2 at the left upper position via the.
The rotary grinding tool 53 is directly connected to the rotary output shaft. The motor 52 is attached to the movable base 54 as shown in FIG. 8 in a posture in which the side on which the rotary grinding tool 53 is located is tilted away from the screw holding means 2 with respect to the rotation axis 5a of the robot hand 5. The movable base 54 is supported by a guide rod 55 so as to be movable within a certain range, and
The compression coil spring 56 urges the object W on which the screw is to be tightened.

The putty filling means 60 and the coating means 70, as shown in FIGS. 1 and 2, are the bearing plates 11 of the screw holding means 2.
Both means 60, 70 are attached to the front side of the screw holding means 2 at the right upper position on the front side of the screw holding means 2 so as to be juxtaposed in the front-rear direction. The putty filling means 60 is composed of a putty feeding pipe 63 having a nozzle 62 at its tip and a compression coil spring 64. The putty feeding pipe 63 is a guide 65 attached to the bracket 61.
The nozzle 62 is attached to the rotation axis 5a of the robot hand 5.
Is supported so as to be able to move in and out within a certain range in such a posture that the side with the edge is inclined away from the screw holding means 2, and the compression coil spring 64 screw-fastens the putty feed pipe 63 to the object W.
To the side with.

The coating means 70 has a brush-shaped coating tool 7 at its tip.
1, a paint supply pipe 72 and a compression coil spring 73
It consists of and. The paint supply pipe 72 is provided on the bracket 6
In the guide 74 attached to No. 1, the screw holding means 2 is provided on the side where the coating tool 71 is located with respect to the rotation axis 5a of the robot hand 5.
The compression coil spring 73 urges the paint feed pipe 72 toward the side on which the object W to be screwed is held, while being supported so as to be able to move in and out within a certain range in a posture of being inclined away from.
Reference numeral 66 is a putty feeding pipe, and 75 is a paint feeding pipe.

An example of the manipulator (industrial robot) 39 equipped with the robot hand 5 is shown in FIG. This manipulator 39 is movable by a guide rail 40 so as to be movable in the X direction on a two-dimensional plane, and by a guide rail 42 on the horizontal motion body 41, is movable in the Y direction orthogonal to the X direction. And a robot main body 44 supported by the vertical moving body 43 so as to be movable in the Z direction perpendicular to the two-dimensional plane.
At the lower end of the robot body 44, a Z-direction axis 44a is formed.
The first arm 45 supported so as to be rotatable around the A direction in the A direction.
And a second arm 46 supported below the tip of the first arm 45 so as to be rotatable in the B direction around an axis 46a parallel to the two-dimensional plane.
The robot hand 5 is rotatably supported in the C direction around an axis 5a orthogonal to 6a.

According to the manipulator 39 described above, the movement of the lateral moving body 41 in the X direction and the movement of the vertical moving body 43 in the Y direction cause any movement on the surface of the object W to be screwed set parallel to the two-dimensional plane. The robot hand 5 can be opposed to the position, and the rotation of the first arm 45 in the A direction and the rotation of the second arm 46 in the B direction allow the robot hand 5 to be oriented in any direction with respect to the surface of the object W to be screwed. Can be tilted at an angle. When the rotation axis 5a of the robot hand 5 is in the Z direction by rotating the second arm 46 in the B direction, the robot hand 5 is moved in the Z direction to move the robot hand 5 in the direction of the rotation axis 5a (screw tightening target). It is possible to reciprocate (elevate) in the direction perpendicular to the surface of the object W.

Prior to starting the screw tightening work, the screw S
As shown in FIG. 4, it is supplied into the screw holding portion 15 between the pair of holders 13a and 13b closed through the screw feeding pipe 17. At this time, as described above, the cylinder unit 1
The piston rod 19a of No. 9 is set in a free state, and the screw holding portion 1 is set by the torsion coil springs 27a and 27b.
5 is held in a screw receiving state (a state shown in FIG. 4) that is slightly wider than the screw clamp state shown in FIG. 5A, the screw S supplied into the screw guide path 16 can smoothly move to the screw holding portion 15 The screw head Sa is fitted into the inside of the screw holding portion 15 and is received by the upper tapered portion of the screw holding portion 15.

As shown by the phantom line in FIG. 4, when the screw S is supplied to a fixed position in the screw holding portion 15, the movable unit 20 is moved away from the robot hand 5 by the cylinder unit 19 shown in FIG. As shown in FIG. 5A, the pair of holders 13a, 13b are twisted to close the brackets 26, links 21a, 21b, and arms 25a, 25b against the urging force of the coil springs 27a, 27b. The screw S in the screw holding portion 15 is moved to a fixed position and clamped. Then, the movable unit 33, the motor 29, and the screw tightening rotary shaft 28 are integrally moved by the cylinder unit 32 shown in FIG. 1 in a direction away from the robot hand 5, and are clamped at a fixed position as shown in FIG. 5A. The screw tightening bit 38 is fitted to the head Sa of the screw S.

When the setting of the screw S for the screw tightening device M is completed as described above, the screw tightening device M is provided at the screw tightening work start position, that is, for screw tightening provided on the screw tightening target W. In the state where the prepared hole H (see FIG. 5B) and the rotation axis 5a of the robot hand 5 are in the concentric state at the screw tightening operation start position, the robot hand 5 causes the screw tightening device M to approach the screw tightening target W. And move it forward in the direction of the robot hand rotation axis 5a,
As shown in FIG. 5B, the tip of the screw S clamped by the pair of holders 13a and 13b and protruding from the tip thereof is pressed into the prepared hole H. In this state, the motor 2 shown in FIG.
The rotary shaft 28 for screw tightening is driven to rotate by 9 and the bit 3
At the same time as rotating the screw S in the screw tightening direction via 8, the movable unit 20 is moved in the direction away from the robot hand 5 by the cylinder unit 19, and the bracket 2
6, links 21a and 21b, and arms 25a and 25b
The pair of holders 13a and 13b are opened via the.

As a result, as shown in FIG. 6A, the pair of holders 13a and 13b are opened to release the screw S, and the screw S that is rotationally driven in the screw tightening direction is prepared in the pilot hole of the object W to be screwed. It will be screwed into H. At this time, the robot hand 5 moves the screw tightening device M closer to the screw tightening target W in the direction of the robot hand rotation axis 5a. The forward speed of the screw tightening device M (robot hand 5) is It is set to be the same as or slightly faster than the screwing speed of S. As a result, the forward force of the robot hand 5 is applied to the screw S via the bit 38, and the screw S, which is rotationally driven in the screw tightening direction, is securely and strongly advanced into the prepared hole H of the object W to be screwed. be able to. At this time, the difference between the screw advancing speed of the screw S (the advancing speed of the screw tightening device M) and the advancing speed of the robot hand 5 is the difference between the robot hand 5 and the screw tightening device M accompanied by the compression of the compression coil spring 6 in the connecting means 4. It is absorbed by the approaching movement with.

The screw head Sa is the prepared hole H of the object W to be screwed.
For the first time, when it is detected that the load applied to the motor 29 that rotationally drives the screw tightening rotary shaft 28 exceeds a set value, or when the screw tightening device M is fixed on the surface of the object W to be screwed. When it is detected that the motor is approaching within the distance, the driving of the rotary shaft 28 by the motor 29 is ended. Then, as shown in FIG. 6B, the robot hand 5 is rotationally driven around its rotation axis 5a in the screw tightening direction. The rotation of the robot hand 5 is caused by the connecting means 4.
Is transmitted to the screw tightening device M via the robot hand rotating shaft core 5a (the screw tightening rotary shaft 2).
Although it will rotate in the screw tightening direction around the shaft center 8), the one-way rotation clutch 31 prevents the screw tightening rotation shaft 28 from rotating in the direction opposite to the screw tightening direction with respect to the frame 1. Therefore, the rotational force of the screw tightening device M (frame 1) in the screw tightening direction is transmitted to the screw tightening rotating shaft 28 via the one-way rotating clutch 31, and the screw S is transferred to the robot hand 5 via the bit 38. It is driven to rotate further in the screw tightening direction by a large torque. Therefore, FIG.
As shown in B, the screw S can be retightened to a depth at which the screw head Sa sinks into the prepared hole H of the object to be screwed W to a predetermined depth.

During the above screw tightening work, the surface grinding means 50, the putty filling means 60, and the coating means 70 are
It is separated upward from the surface of the object W to be screwed. When the screw tightening is completed, the robot hand 5 is moved to its rotation axis 5
The bit 38 is moved in the direction away from the screw tightening target W along a, the bit 38 is disengaged from the screw head Sa, and the cylinder unit 3 of the lifting drive unit 30 shown in FIG.
The movable base 33 is moved backward by 2 to move the screw tightening rotary shaft 28 and its rotary drive motor 29 backward in the direction of approaching the robot hand 5, and the cylinder unit of the holder opening / closing drive means 14. The movable table 20 is moved forward by 19 and the pair of holders 13a and 13b are connected via the links 21a and 21b and the arms 25a and 25b.
After the cylinder is closed, the cylinder unit 19 is switched to the free state, so that the pair of holders 13a, 13b
The torsion coil springs 27a and 27b shown in FIG.
By doing so, the screw receiving state shown in FIG. 4 may be restored.

On the other hand, if the screw holding means 2 is moved upward from the screw tightening portion as described above, the position, direction and angle of the screw tightening device M are moved by the manipulator 39 shown in FIG. Changed Figure 1B
As shown in FIGS. 7 and 8, the imaginary line of FIG.
No. 0 rotary grinding tool 53 and nozzle 62 of putty filling means 60
And are moved to the left and right sides of the screw holding means 2 in the arrow D1 direction, and the rotary grinding tool 53 of the surface grinding means 50 is moved to the screw tightening point P in the arrow D2 direction. At this time, the height of the robot hand 5 (screw tightening device M) is set so that the rotary grinding tool 53 comes into contact with the surface of the screw tightening object W at the screw tightening point P and moves backward against the biasing force of the spring 56. By performing the control, as shown in FIG. 9A, the rotary grinding tool 53 that is rotationally driven by the motor 52 grinds and removes the return portion Wa that is raised on the surface of the object W to be screwed at the screwing point P. be able to.

Next, as shown in FIGS. 1B and 8, the nozzle 62 of the putty filling means 60, which has been moved away from the screw tightening point P in the arrow D2 direction by the grinding step, is moved by the manipulator 39 shown in FIG. 3 in the arrow D3 direction. Then, the nozzle 62 is moved to the screw tightening point P. At this time, the height of the robot hand 5 (screw tightening device M) is controlled so that the nozzle 62 comes into contact with the surface of the screw tightening target W at the screw tightening point P and moves backward against the urging force of the spring 64. By doing so, as shown in FIG. 9B, the nozzle 62 can be positioned so that the nozzle 62 covers the recess Wb in which the screw head Sa formed in the screw tightening point P is depressed. When the nozzle 62 is positioned in this way, the putty discharged from the nozzle 62 is discharged by pressing the putty by a predetermined amount to the nozzle 62 through the putty feeding pipe 66 and the putty feeding pipe 63. Can be filled inside.

When the putty filling is completed, the coating tool 71 of the coating means 70 located immediately behind the screw tightening point P is in contact with the surface of the screw tightening object W at the screw tightening point P, The manipulator 39 shown in FIG. 3 is moved in the direction of the arrow D4 shown in FIG. 9C (the direction opposite to the direction of the arrow D3 shown in FIG. 1B), and at the same time, the paint feeding pipe 7
5 and the paint feed pipe 72, the paint is discharged from the paint tool 71 by a predetermined amount so that the paint discharged from the paint tool 71 causes the surface of the screw tightening target W at the screw tightening point P, that is, shown in FIG. 9C. Thus, the surface of the recess Wb filled with the putty Wc and the ground surface around it can be coated.

A robot hand 5 to which the screw tightening device M according to the present invention is attached, that is, a manipulator (industrial robot) equipped with the robot hand 5 which can be moved to an arbitrary position and whose direction and angle can be arbitrarily changed. Is not limited to the structure shown in FIG. 3, and may be, for example, a multi-joint arm type manipulator.
Further, in the above-described embodiment, the screw S is a screw tightening device that vertically tightens the screw S from top to bottom, but the screw tightening direction can be a horizontal horizontal direction or an oblique direction at an arbitrary angle. . Of course, when the screw S cannot be gravity-supplied to the screw holding portion 15 between the pair of holders 13a and 13b depending on the direction of the screw tightening device M, an appropriate compulsory screw supplying means is also used. There must be.

Further, in the above-mentioned embodiment, the coating means 70 is also used, but this coating means 70 is not essential to the present invention and can be omitted depending on the situation.

[0031]

As described above, the robot hand is
According to the screw tightening device of the present invention used by being attached to (5), the screw guideway (16) is provided in the screw holding part (15) between the pair of holders (13a, 13b) of the screw holding means (2). Screws fed through
(S) can be screwed by, for example, screwing into the prepared hole of the object to be screwed by the rotating shaft (28) for screwing the screwing means (3). 2)
A surface grinding means (50) for the object to be screwed (W) and a putty filling means (60) are provided separately from the screw tightening means (3) and the surface grinding means (50) and the putty filling means (50). 60) is located at a position laterally above the screw holding means (2), and the screw holding means (2) is selectively tightened by moving the robot hand (5) and changing the angle. Since it is adjacent to the screw tightening point of the object (W), the grinding tool (53) of the surface grinding means (50) is moved by the robot hand (5) after the screw tightening process by the screw tightening means (3) is completed. Adjacent to the screw tightening point (P), grind away the raised return part (Wa) formed by screwing the screw head with the grinding tool (53),
The surface of the screw tightening place was ground flatly, and then the nozzle (62) of the putty filling means (60) was made adjacent to the screw tightening place (P) by the robot hand (5) and discharged from the nozzle (62). The putty (Wc) is a recess (Wb) formed by the depression of the screw head.
The surface of the screw tightening point (P) can be finished flat.

Therefore, in the past, grinding and removal of the swelling return portion on the surface of the screw tightened portion, which has conventionally relied on the manual work of the operator,
It is possible to automatically perform two post-treatments of putting putty on the recesses of the screw-fastened portions subsequent to the screw-fastening process, and to completely rationalize all the processes including these post-treatments.

According to the second aspect of the invention, the grinding tool (53) of the surface grinding means (50) is moved to a predetermined position on the surface of the object (W) to be screwed by the compression reaction force of the spring (56). Grinding tool with robot hand (5) as it can be pressed
Even if the accuracy of the height control of (53) is somewhat low, it is possible to grind the surface of the screw tightened portion reliably and comfortably.

According to the third aspect of the present invention, the nozzle (62) of the putty filling means (60) is brought to a predetermined position on the surface of the object (W) to be screwed by the compression reaction force of the spring (64). Since they can be pressed together, the nozzle (6
Even if the accuracy of the height control of 2) is somewhat low, the putty can be filled into the recessed portion where the screw head at the screw tightening portion is depressed reliably and comfortably without flowing out to an unnecessary portion.

Further, according to the structure of claim 4, the coating tool (71) of the coating means (70) can coat the surface grinding mark of the screw tightening portion (P) and the surface of the filling putty. When the object to be screwed (W) requires such coating, the final coating process can be continuously and automatically performed to further rationalize.

[Brief description of drawings]

FIG. 1 is a partially longitudinal side view showing a screw tightening device attached to a robot hand, and FIG. 1B shows relative positions of screw holding means, surface grinding means, putty filling means, and coating means. It is a schematic plan view.

FIG. 2A is a front view showing a screw tightening device attached to a robot hand, and FIG. 2B is a side view of an essential part showing relative positions of a screw holding means, a putty filling means, and a coating means. .

FIG. 3 is a schematic perspective view showing an example of a manipulator (industrial robot) including a robot hand.

FIG. 4 is a partial vertical cross-sectional side view showing a main part when the screw tightening device is in a screw receiving state.

FIG. 5 is a partial vertical cross-sectional side view showing an essential part when the screw tightening device is in a screw clamp state, and FIG. 5 is a partial vertical side view showing a main part when the screw tightening work is started. Is.

FIG. 6 is a side view of a part of a main part showing a state when a screw tightening process is completed by a rotating shaft for screw tightening, and FIG. 6 is a part of a main part showing a state of retightening with a robot hand. FIG.

FIG. 7 is a side view showing a state immediately before operating the surface grinding means.

FIG. 8 is a front view showing a surface grinding means and a putty filling means.

FIG. 9 is a diagram illustrating each stage of post-treatment after the screw tightening process.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Frame of a screw tightening device 2 Screw holding means 3 Screw tightening means 4 Coupling means 5 Robot hand 5a Rotating shaft core of robot hand 6 Compression coil spring 12 Spindle of a pair of holders 13a Holder 13b Holder 14 A pair of holders Opening / closing drive means 15 Screw holding part 16 Screw guide path 19 Cylinder unit 20 Moving stand 21a Link 21b Link 25a Holding tool arm 25b Holding tool arm 27a Twisting coil spring 27b Twisting coil spring 28 Rotating shaft for screwing 29 Rotational drive motor 30 Elevating and lowering drive means for screw tightening rotary shaft 31 One-way rotation clutch 32 Cylinder unit 33 Movable table 38 Screw tightening bit 50 Surface grinding means 52 Motor 53 Rotary grinding tool 54 Movable table 55 Guide rod 56 Compression coil spring 0 Putty filling means 62 Nozzle 63 Putty feeding pipe 64 Compression coil spring 70 Painting means 71 Brush-like paint tool 72 Paint feeding pipe H Pilot hole for screw tightening target M Screw tightening device P Screw tightening point S Screw Sa Screw head W Screw tightening object Wa Raised return part Wb Recessed part Wc Putty

Claims (4)

[Claims] 1. A screw tightening device (M) attached to a robot hand (5), comprising a screw holding means (2), a screw tightening means (3), and a surface grinding means for screwing an object (W). (50),
The putty filling means (60) is provided, and the screw holding means (2) has a pair of holders (13a, 13b) that are driven to open and close by the opening and closing drive means (14).
3a, 13b) include a screw retainer (15) that holds the screw (S) in place when closed and a screw (S) into the screw retainer (15).
A screw guide path (16) for guiding the screw is provided, and the screw tightening means (3) includes a rotating shaft (28) for screw tightening, a rotation driving motor (29) for the rotating shaft (28), and the rotating shaft. The shaft (28) has an elevating / lowering drive means (30) for reciprocating in its axial direction, and the screw tightening rotary shaft (28) has a screw of the pair of holders (13a, 13b) at its tip. Screws retained in retaining part (15)
Bit (38) for screw tightening that can be engaged with the head (Sa) of (S)
The surface grinding means (50) and the putty filling means (60) are arranged at positions laterally above the screw holding means (2), and
By moving (5) and changing the angle, the screw holding means (2) can be replaced instead of the screw tightening point (P) of the screw tightening target (W).
The surface grinding means (50) is a grinding tool (5) that grinds the surface of the screw tightening target (W) evenly.
3), the putty filling means (60) is provided with a recess (W
A screw tightening device having a nozzle (62) for filling the putty in b). 2. The grinding tool (53) of the surface grinding means (50) moves within a certain range in the vertical direction with respect to the surface of the object to be screwed (W) when it is in a posture of facing the screwing point (P). The spring (56) urges the surface of the object (W) to be tightened, and when it comes into contact with the screw tightening point (P), it is tightened by the urging force of the spring (56). Object
The screw tightening device according to claim 1, which is pressed against the surface of the (W). 3. The object to be screw-fastened when the nozzle (62) of the putty filling means (60) is in a posture of facing the screw-fastening point (P).
It is movable within a certain range in the vertical direction with respect to the surface of (W), and is biased by the spring (64) toward the surface of the object to be screwed (W) so that it comes into contact with the screw tightening point (P). Sometimes the object to be screwed by the spring force of the spring (64)
The screw tightening device according to claim 1 or 2, which is pressed against the surface of (W). 4. A robot hand provided with a coating means (70).
By moving (5) and changing the angle, only the coating means (70) can be adjacent to the screw tightening point of the object to be screwed (W), and a paint tool for painting the surface of the screw tightening point (P). The screw tightening device according to claim 1, further comprising (71).