JPH03281189A - Working tool device - Google Patents

Abstract

PURPOSE:To absorb displacement between a workpiece and a reference workpiece by slidably engaging a slide member internally of a cylinder body mounted on the wrist of a robot. CONSTITUTION:Through drive of a tool, a workpiece is machined. In this case, a slide member 2 is slidably guided in a cylinder body 1 mounted on a wrist part. Floating operation in a slide direction is produced by energizing the slide member by means of a given press force generated by an energizing means and absorbs displacement between a workpiece in a floating direction and a working tool device. The axial direction of the tool is not extended in the same direction as the direction of the normal of the surface to be processed of a workpiece, and when contact of the tool with the workpiece is insufficient, a tool holder supported to a spherical bearing is inclined by means of a reaction force exerted on the tool by the workpiece, and the angle of the tool with the surface to be machined is changed so that the axial direction of the tool coincides with the direction of the normal of the surface to be machined.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a power tool device that is attached to the wrist of a robot and is particularly suitable for performing polishing work.

<Prior art> As shown in FIG. 6, a conventional power tool device teaches a robot a machining trajectory on a reference workpiece, and drives a rotary grindstone (tool) 27 attached to the tip with a drive motor 60. The floating device 26 presses the rotary grindstone 27 against the workpiece 50 at a predetermined pressure to polish the workpiece 50. Here, the floating device 26 presses the piston 61 with air pressure to urge and hold the rotary grindstone 27 in a certain direction with a predetermined pressing force. The rotary grindstone 27 absorbs the displacement that occurs between the workpiece 50 and the reference workpiece due to the state of the machined surface, the deviation of the position where the workpiece 50 is installed, etc. by floating in the direction in which the piston 61 moves. It was also effective.

<Problem to be solved by the invention> In a power tool device such as the conventional technology, the workpiece 50
Displacement in the same direction as the movement of screws 1 to 61 on the machined surface can be absorbed, but when polishing a free-form surface such as an automobile body, displacement occurs in multiple directions.
It is not possible to absorb all these displacements. Therefore, the rotation center axis 101 of the rotary grindstone 27 and the normal line 102 of the machining surface
are not in the same direction, that is, the grinding wheel surface 90 of the rotary grindstone 27 is likely to not be in proper surface contact with the target machining position of the workpiece 50, and the machining state of the workpiece 50 after machining may be unstable. There are problems in that the workpiece 50 becomes uniform, or the workpiece 50 is processed more than necessary, resulting in deterioration in quality. Furthermore, in order to avoid such problems, robots are taught machining trajectories that match free-form surfaces, but this work is very time consuming and does not provide sufficient results.

The present invention solves these problems, and even when polishing free-form surfaces such as automobile bodies, the axial direction of the tool and the normal direction of the machined surface are in the same direction, so that the tool can be properly adjusted. It is an object of the present invention to provide a power tool device that can carry out uniform and good machining by bringing it into contact with the machining surface of a workpiece.

<Means for Solving the Problems> The present invention has been made to solve the above-mentioned problems, and includes a cylinder attached to the wrist of a robot, and a cylinder that is slidably inserted into the cylinder. a sliding member, a biasing means that biases the sliding member with a predetermined pressing force, a frame attached to the sliding member, a spherical bearing fixed to the frame, and a tilting member that is tilted by the spherical bearing. a tool holder mounted on the tool holder and a drive device for rotationally driving the tool; a first stopper for limiting the tilting angle of the tool holder; It is characterized by comprising a second stopper that limits the angle of rotation around the same axis as the axial direction.

<Operation> In the work tool device configured as described above, the drive device drives the tool to process the workpiece.

At this time, the sliding member is slidably guided inside the cylindrical body and is biased with a predetermined pressing force by the biasing means to have a floating action in the sliding direction, and the workpiece in this floating direction and work tool equipment.

In addition, if the axial direction of the tool and the normal direction of the machined surface of the workpiece are not in the same direction, and the way the tool contacts the workpiece is insufficient, the reaction force that the tool receives from the workpiece may cause the spherical surface to The tool holder supported by the bearing is tilted to change the angle of the tool with respect to the machined surface so that the axial direction of the tool and the normal direction of the machined surface become the same direction. The first stopper is configured such that when the tool tilts excessively, the axial direction of the tool is tilted to a greater extent than the direction of the central axis of the power tool device, and the above-mentioned floating action of the sliding member in the same direction as the central axis of the power tool device is caused. To prevent the tool holder from working effectively, the angle at which the tool holder tilts is limited. prevent.

<Example> Ru.

As shown in FIG. 4, the robot (10 is a 6-axis robot) is taught a machining trajectory on a reference workpiece, and performs polishing work using a rotary grindstone 27 of a working tool device 20 attached to the tip of an arm 15. The workpiece 50 is an automobile frame, and is used for polishing work to remove dirt and the like during the painting process.

The work tool device 20 has a floating cylinder section 26 that urges and holds the rotary whetstone 27 with a predetermined pressing force, drives the rotary whetstone 27, and uses the reaction force that the rotary whetstone 27 receives from the workpiece 50 to press the rotary whetstone 27. It is composed of an attitude changing section 28 that changes the angle with respect to the workpiece 50.

FIG. 3 is a diagram showing the floating cylinder section 26 of the power tool device 20. The floating cylinder section 26 is attached to the tip of the wrist section 17 of the robot 10,
The device is composed of a cylindrical cylinder part 1 and a sliding part 2 that slides inside the cylinder part 1. The cylinder part 1 consists of guide members 3a, 3b, and 3c, and the guide members 3a and 3b are integrally connected by circuit bolts. are integrally connected. The cylinder portion 1 is provided with a first cylinder chamber 4 formed by guide members 3a, 3b, and 3c, and a second cylinder chamber 5 formed inside the guide member 3c. The sliding part 2 consists of sliding members 10a, 10b and a mounting part 11,
These are connected to each other by circuit bolts. The sliding member 10a moves inside the first cylinder chamber 4 through the linear bushing 1.
2, one end is formed with a piston portion 12,
A mounting portion 11 is fixed to the other end. Sliding member]O
b slides inside the second cylinder chamber 5, and one end is attached to the part 11.
Fixed. An air supply port 6 and an air discharge port 8 are formed in the first cylinder chamber 4, and the piston portion 12 is pressed and slid by the pressure of compressed air supplied through the air supply port 6 from the air supply source of the circuit. Move the part 2 in the direction of pushing it into the cylinder part I.

An air supply lower is formed in the second cylinder chamber 5, and the pressure of compressed air supplied from the air supply source of the circuit through the air supply lower presses the end face of the sliding member 10b to move the sliding part 2 into the cylinder. Move it in the direction of pushing it out from part 1. A stopper 13 that comes into sliding contact with the cylinder portion 1 is attached to the mounting portion 11 . The stopper 13 is configured such that when the sliding part 2 slides with respect to the cylinder part 1, a pin 14 attached to the cylinder part 1 moves in the elongated hole 15 formed in the collar I3 relative to the elongated hole 15 in the longitudinal direction. Move to pin 1
4 comes into contact with the inside of the slotted hole 5, the sliding part 2
At the same time, the sliding portion 2 is prevented from rotating relative to the cylinder portion l.

1 and 2 show the floating cylinder section 26
The posture changing part 28 is shown attached to the handle part 11 of the figure. A rotary grindstone 27 is attached to the tip of the attitude changing section 28, and a cover 29 is attached so as to surround this. The rotary grindstone 27 is rotated by the rotation center shaft 10 by an air motor 31 inside the drive unit 30 via an eccentric rotation mechanism of the circuit.
It is designed to rotate eccentrically around 1. The tool holder 30 is supported by the frame 45 via a spherical bearing 32 so that the rotation center axis 101 of the rotary grindstone 27 can be tilted with respect to the center axis 100 of the power tool device 20 by an external force.

The first stopper 70 is formed at an angle of inclination from the center axis 1IIAI 00 of the rotation center shaft 101 by the projection 37 attached to the frame 45 coming into contact with the inside of the cylindrical recess 33 integrally formed in the tool holder 30. is limited to approximately 5°. Further, the second stopper 80 rotates the tool holder 30 around the central axis 100 when the abutment pin 34 attached to the tool holder 30 abuts the inner wall of the pair of locking plates 38 attached to the frame 45. There are restrictions on what you can do. Posture return mechanisms 39 are disposed on both sides of the recess 33 to align the rotation center axis 101 of the rotary grindstone 27 with the center axis 100 of the power tool device 20 . The posture return mechanism 39 includes a pair of posture return members 40 that are arranged facing each other and have a groove 95 formed therein. This posture return member 40
is moved by the pressure of air supplied through the air supply port 42 from the air supply source of the circuit, and by sandwiching the recess 33 from both sides, moves the recess 33 in the direction of the central axis 100 along the groove 95. The inclination of the central axis of rotation 101 from the central axis 100 is O. Since the buff 41 is attached between the pair of posture return members 40, the reaction force of this spring 41 causes the posture return member 40 to
is returned to the state before the move.

Next, the operation of the above embodiment will be explained. At the start of machining, the springs 41 keep the posture return members 40 apart from each other. The robot 10 presses the rotary grindstone 27 against the workpiece 50 according to the taught machining trajectory to perform machining. At this time,
The floating cylinder section 26 adjusts the amount of air supplied from the air supply port 6 and the air supply lower so that the rotary grindstone 27 is always pressed against the workpiece 50 at a constant pressure. Further, the work tool device 20 is placed on the processing surface of the workpiece 50.
When a displacement occurs in the same direction as the central axis 1.00 of 0, a force in the direction of pushing the sliding part 2 into the cylinder part 1 acts to absorb this displacement.

As shown in FIG. 5(a), when the normal 102 of the machined surface of the workpiece 50 and the rotation center axis 101 of the rotary grindstone 27 are not in the same direction, the grindstone surface 90 of the rotary grindstone 27 comes into surface contact with the machined surface. Instead, it comes into contact with the machined surface near the outer periphery of the rotary grindstone 27.

At this time, the rotating grindstone 27 receives a reaction force F from the machined surface.

This reaction force F causes the spherical bearing 32 of the attitude changing section 28 to rotate, so that the normal 102 of the machined surface and the rotation center axis 101 of the rotary grindstone 27 are in the same direction as shown in FIG. 5(b). Therefore, due to the action of the attitude changing portion 28, the grindstone surface 90 of the rotary grindstone 27 comes into surface contact with the processing surface, allowing appropriate processing.

In the above process, the first stopper 70
7 is tilted excessively, the rotation center axis 101 of the rotary grindstone 27 is tilted more than the center axis 100 of the power tool device 20, and the floating action in the same direction as the center axis 100 of the floating cylinder part 26 is prevented from working.

Further, the second stumper 80 is configured to rotate the workpiece 50 of the rotary grindstone 27.
The rotation relative to the frame 45 becomes zero, and the tool holder 30 is prevented from rotating with respect to the frame 45.

<Effects of the Invention> As described above, the power tool device of the present invention absorbs the displacement generated between the workpiece and the reference workpiece due to the floating action of the sliding member, and polishes a free-form surface by tilting the tool holder. Since the tool can be appropriately brought into contact with the processing surface when polishing, the polishing work can be performed uniformly and satisfactorily. In addition, since there is no need to teach the robot a complicated machining trajectory, the time required to teach the machining trajectory is Figure 2 is a view showing the posture changing part, Figure 2 is a view from the ■ arrow in Figure 1, Figure 3 is a diagram showing the floating cylinder part, Figure 4 is an overall configuration diagram of this embodiment, and Figure 5 is this embodiment. FIG. FIG. 6 is a diagram showing the prior art.

■...Cylinder part, 2...Sliding part, 6, 7...Air supply port, 10...Robot, 17...Wrist part, 2
0...Work tool device, 27...Rotary grindstone, 30...
・Tool boulder, 31... Air motor, 32... Spherical bearing, 45... Frame, 50... Workpiece, 70...
...1st stopper, 80...2nd stopper.

Claims (1)

[Claims] (1) A work tool device for machining a workpiece using a tool attached to the tip of the wrist of a robot, which includes a cylinder attached to the wrist of the robot and a cylinder that is slidably fitted inside the cylinder. an inserted sliding member, a biasing means for biasing the sliding member with a predetermined pressing force, a frame attached to the sliding member, and a spherical bearing fixed to the frame;
a tool holder tiltably supported by the spherical bearing; a tool attached to the tool holder; a drive device for rotationally driving the tool; a first stopper for limiting the tilting angle of the tool holder; A power tool device comprising: a second stopper that limits the angle at which the holder rotates about the same axis as the axial direction of the tool.