JPH03176B2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention uses an electrical machining device such as an electrical discharge machining device or an electrolytic machining device, in particular, uses a multi-joint arm, and a mechanical hand is provided at the tip of the arm to grip an electrode. The present invention relates to an electrical processing device that performs processing.

The feature of this multi-joint arm is that compared to manipulators with Cartesian coordinates, cylindrical coordinates, polar coordinates, etc., the arm motion is closest to that of a human arm, allowing for flexible motion. It is possible to work from various directions. On the other hand, since it has many turning parts, there is a drawback that errors in the servo mechanism that drives each arm accumulate at the tip of the arm, and the operation accuracy is not sufficiently high.

Therefore, an electric machining device that uses a mechanical hand at the end of a multi-joint arm to grip and process an electrode has the advantage of being able to process a single workpiece from various directions. However, it is difficult to maintain the relative positional relationship between the electrode and the workpiece with high accuracy, and the processing accuracy has not been sufficiently high.

In particular, in electric discharge machining equipment, the accuracy of the central axis angle of the electrode relative to the workpiece is important, but there has been a problem in that it is difficult to keep this angle error low.

Furthermore, when attempting to provide machining feed using such a multi-joint arm, it is difficult to move the electrodes completely in parallel, so accidents such as short circuits are unavoidable.

The present invention has been made based on the above-mentioned viewpoints, and an object of the present invention is to improve the relative relationship between an electrode held by a mechanical hand provided at the tip of a multi-jointed arm and a workpiece. The object of the present invention is to improve the machining accuracy by configuring the machine so that machining feed can be performed while maintaining a high-precision positional relationship.

Therefore, the gist of the present invention is to provide an electrode holder having a plurality of guide holes, a die set having positioning pins provided corresponding to each of the guide holes, and an articulated arm and a mechanical hand. The object of the present invention is to provide a servo mechanism for driving and a control device for controlling the servo mechanism so as to be able to perform machining and feeding while maintaining the relative positional relationship between the electrode and the workpiece with high precision.

Hereinafter, the details of the present invention will be explained based on the drawings.

The drawing is an explanatory diagram showing an embodiment of an electrical processing apparatus according to the present invention.

1 is the base, 2 to 4 are the arms, 5 is the head, 6
is a servo motor that rotates the arm 2; 7 is a hydraulic cylinder that rotates the arm 3; 8 is a hydraulic cylinder that rotates the arm 4; 9 is a hydraulic cylinder that rotates the arm 4; A servo motor 10 is a servo motor that rotates the head 5 in a plane orthogonal to the plane containing the axis 11 of the head 5 described later; 11 is a shaft inserted through the head; 12 is a servo that rotates the shaft 11; 14 is a mechanical hand; 15 is an electrode; 16 is an electrode holder; 16a, 16a are guide holes provided in the electrode holder 16; 17 is a workpiece; 18 is a workpiece A die set to which the body 17 is attached, 18a, 18a are positioning pins provided on the die set, 19 is a processing tank, and 20 is a control device. The arm 2 is rotatably attached to the base 1, and can be rotated at any angle by driving a servo motor 6.

The arm 3 is rotated relative to the arm 2 by driving a hydraulic cylinder 7.

The arm 4 is rotated relative to the arm 3 by driving a hydraulic cylinder 8.

The motion of arms 2 to 4 provides three degrees of freedom, and the tip of arm 4 can take any position in three-dimensional space within its motion range.

The head section 5 is attached to the tip of the arm 4, and as mentioned above, the arm 4 is driven by the servo motor 9.
It is rotated by a servo motor 10 within a plane including the axis 11, and rotated by a servo motor 10 within a plane perpendicular to the plane.

The shaft 11 is inserted through the head portion 5, rotated by a servo motor 12, and expanded and contracted in the axial direction by a servo motor 13.

By the operation of the head section 5 and the shaft 11, the shaft 11
Mechanical hand 14 attached to the tip of
can take any position.

The mechanical hand 14 has claws 14a, 14a that can grip the shaft of the electrode holder 15.
a, 14a are driven by a servo motor (not shown) provided inside the mechanical hand 14.

In addition to the servo motor and hydraulic cylinder shown in this embodiment as the actuator of the servo mechanism that drives the arms 2 to 4, the head portion 5, the shaft 11, and the claws 14a, 14a of the mechanical hand 14, a step pin motor may be used as necessary. , a hydraulic motor, etc. can be used.

The electrode 15 is attached to an electrode holder 16 at a predetermined position.

The electrode holder 16 has a plurality of guide holes 16a, 16a at predetermined positions separated from the electrode 15 by an appropriate distance.
are arranged parallel to each other.

The die set 18 is a processing tank 1 in which processing fluid is stored.
9, and a workpiece 17 is attached thereto.

The die set 18 has positioning pins 18a, 18.
a are provided parallel to each other at predetermined positions separated from the workpiece 17 by an appropriate distance, and each positioning pin 18
The diameter and position of a and 18a correspond to the diameter and position of each guide hole 16a and 16a provided in the electrode holder 16, respectively, and each positioning pin 18a and 18
a is inserted into each guide hole 16a, 16a, the electrode holder 16 and die set 18 are configured to be able to move in parallel, and their directions are fixed.

Further, the tip of each positioning pin 18a, 18a is formed in a tapered shape, and the guide hole 16a,
When the positioning pins 18a, 18a are inserted into the corresponding guide holes 16a,
Even if the centers of the positioning pin 18a and the center of the positioning pin 18a are not exactly on the same straight line and have some error, the positioning pin 18a is configured to be easily inserted.

Although not shown, an electrode magazine containing electrode holders to which electrodes suitable for various types of processing are attached is provided within the operating range of the arms 2 to 4.

The control device 20 controls a servo motor 6, hydraulic cylinders 7, 8, servo motors 9, 10, 12, 13, and a mechanical hand 14, which drive the arms 2 to 4, the head section 5, and the shaft 11 according to a predetermined program. The driving servo motor (not shown) is collectively controlled.

Accordingly, the arm 2 is
4 are driven by a servo motor 6 and hydraulic cylinders 7 and 8, the head part 5 is driven by servo motors 9 and 10, and the mechanical hand 14 attached to the tip of the shaft 11 is an electrode magazine. (not shown) to a position facing the electrode holder 16 to which the desired electrode 15 is attached.

When the mechanical hand 14 finishes moving to the above position, the shaft 11 is driven by the servo motor 13, and the mechanical hand 14 moves to the electrode holder 16.
It extends and extends until it approaches , and then stops. Thereafter, the claws 14a, 14a of the mechanical hand 14 are driven by a servo motor (not shown) provided inside the hand 14 to grip a desired electrode holder 16.

Next, after the servo motor 13 is activated to retract the shaft 11 and the electrode holder 16 is taken out from the electrode magazine, the control device 20 drives the servo motor 6, hydraulic cylinders 7, 8, and servo motors 9, 10, 13. The mechanical hand 14 is controlled to move the arms 2 to 4 and the head part 5, and also controls the drive of the servo motor 12 to rotate the shaft 11.
The electrode holder 16 held by
The pins 6a and 16a are moved so that they are opposed to the positioning pins 18a and 18a provided on the die set 18, and their centers are on the same straight line.

At this time, the tool 15 attached to the electrode holder 16 is positioned opposite to the position of the workpiece 17 to be machined.

When the mechanical hand 14 finishes moving to the above position, the shaft 1 is driven by the servo motor 13.
1 is extended and the guide holes 16a, 16 of the electrode holder 16 held by the mechanical hand 14
Locating pins 18a, 18 of the die set 18 are attached to a.
a is inserted.

Although the accuracy of positioning the electrode holder 16 by the multi-joint arm is not sufficiently high, it is sufficient to ensure that the centers of the guide holes 16a, 16a provided in the electrode holder 16 are approximately on the same straight line as the centers of the positioning pins 18a, 18a. Have precision.

Also, the centers of both are not exactly on the same straight line,
Even if there is some error, the positioning pin 18
Since the tips of a and 18a are tapered, they can be inserted easily.

Positioning pins 18 are placed in the guide holes 16a, 16a.
When a, 18a are inserted, the electrode holder 16 is movable parallel to the die set 18, and its relative direction is fixed.

Therefore, the electrode 15 attached to the electrode holder 16 is movable parallel to the workpiece 17, and its relative direction is accurately fixed.

Thereafter, the electrode 15 is moved in parallel by a minute distance by the extension of the shaft 11 while maintaining the above-mentioned relative direction with respect to the workpiece 17, and approaches the workpiece 17, whereupon machining is performed.

Since the present invention is constructed as described above, when the present invention is used, the relative positional relationship between the electrode and the workpiece can be maintained with high accuracy during machining, and machining feed can be performed, and the electric Processing equipment can be provided.

In the above-mentioned embodiment, only one surface of the workpiece is processed, but the present invention is applicable when processing multiple surfaces or parts of a large workpiece. In this case, positioning pins are provided corresponding to each processing surface, and a predetermined electrode corresponding to the processing surface or processing part is selected from the electrode magazine and gripped by a mechanical hand to correspond to each processing surface. It is configured to face the processing area and be fed for processing.

Further, processing feed into the workpiece 17 guided by the pins 18a, 18a is normally performed by elongating the shaft 11 in the axial direction by the servo motor 13;
If the stroke is insufficient, the hydraulic cylinders 7 and 8 and furthermore the servo motor 9 may work together to perform processing or to update and set a new reference position.

Note that the configuration of the present invention is not limited to the above-mentioned embodiment, and in the above-mentioned embodiment, the electrode holder is provided with a guide hole and the electrode is attached to this. It may be formed integrally with a guide hole provided therein. Of course, the electrode referred to here may also be the electrode of the workpiece 17.

Furthermore, the design of the degree of freedom of the arm and hand and the configuration of the servo mechanism for driving them can be freely changed within the scope of the object of the present invention, and the present invention encompasses all of them.

[Brief explanation of the drawing]

The drawing is an explanatory diagram showing an embodiment of an electrical processing apparatus according to the present invention. 1...Base, 2-4...Arm, 5...Head part,
6, 9, 10, 12, 13...servo motor, 7,
8... Hydraulic cylinder, 11... Shaft, 14... Mechanical hand, 15... Electrode, 16... Electrode holder, 16
a, 16a... Guide hole, 17... Workpiece, 18...
Die set, 18a, 18a...locating pin, 1
9... Processing tank, 20... Control device.

Claims (1)

[Scope of Claims] 1. In an electric processing device that has a multi-jointed arm and has a mechanical hand at the tip of the arm, which grips and processes an electrode or an electrode holder, a plurality of guides are provided. An electrode holder having a hole, a die set having positioning pins provided corresponding to each of the guide holes, a servo mechanism that drives the multi-joint arm and the mechanical hand, and a control device that controls the servo mechanism. An electrical processing device comprising: