JPH0472649B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an automatic wire electrode setting method and apparatus that can automatically set a wire electrode in a wire cut electric discharge machining apparatus.

(Prior Art) Various devices that can automatically set wire electrodes in wire-cut electric discharge machining equipment have been proposed, but the biggest problem with automatic wire electrode setting is Another issue is how to prevent buckling of the wire electrode that occurs during insertion when the wire electrode has a small diameter. To solve this problem, for example,
The tip of the wire electrode is annealed to make it straight, and a guide pipe is prepared so that the wire electrode can pass smoothly through the guide.The wire electrode is guided to the machining start hole by the guide pipe, and the wire electrode is Methods have been proposed to ensure that the wire is inserted into the machining start hole, to apply a jet jet when the wire guide is opened, and to feed the wire into the guide by the jet jet.

(Problems to be Solved by the Invention) Methods and are effective when the wire electrode has a certain degree of rigidity, but if the diameter of the wire electrode is extremely small, the wire electrode may become attached to the wire guide during feeding. If there is even a slight contact, buckling occurs, making it impossible to maintain its straightness and making it impossible to insert it into the wire guide. On the other hand, with the method (2), if the machining starting hole of the workpiece is small in diameter, it is not possible to expect the insertion effect by the jet jet, and especially when setting the wire electrode in water or oil, the jet jet will not work. The problem is that the force becomes significantly weaker, making it impossible to automatically set the wire.

In addition, when setting the wire electrode, it is necessary to insert the wire electrode into the machining start hole that is pre-formed in the workpiece, but if the diameter of this machining start hole is small, the wire electrode Another problem is how to smoothly insert the material into the processing start hole.

Therefore, an object of the present invention is to be able to reliably insert a wire electrode into a wire guide for automatic setting even when the wire electrode has an extremely small diameter, and also to make it possible to securely insert the wire electrode into the wire guide for automatic setting of the wire electrode. It is an object of the present invention to provide a method and device for automatically setting a wire electrode for a wire cut electrical discharge machining apparatus, which allows the wire electrode to be automatically set extremely easily even when the diameter is small.

(Means for Solving the Problems) The feature of the method of the present invention for achieving the above object is that a machining start hole is formed in a workpiece by electric discharge machining using a conductive cylindrical body, and the machining start hole is supplied from a supply reel. A wire electrode automatic setting method for a wire cut electric discharge machining apparatus for automatically setting a wire electrode to a required wire electrode running path passing through a pair of wire guides provided near the machining start hole and the workpiece. After the free end of the wire electrode is inserted into the inside of the cylindrical body, the wire electrode is fixed to the cylindrical body by crushing a part of the cylindrical body, and the wire electrode is fixed to the cylindrical body. The wire electrode is pulled by the cylindrical body to set the wire electrode on the desired wire electrode travel path.

The apparatus of the present invention is characterized by a wire electrode supply device that supplies a wire electrode, a first wire guide that guides the wire electrode supplied from the wire electrode supply device, and a first wire guide that guides the wire electrode through the workpiece. An automatic wire electrode setting device for a wire cut electrical discharge machining device, comprising a second wire guide disposed opposite to the second wire guide, and a take-off device for taking out the wire electrode taken out through the second wire guide,
A holder for holding at least one cylindrical body that can be used as an electrode for electric discharge machining, and prior to setting the wire electrode, the cylindrical body inside the holder is removed and the wire electrode supply device and the first wire guide are connected to the holder. a take-out device for arranging the cylindrical body on a wire electrode passageway between the cylindrical body and 2. a connecting device for fixing the wire electrode to the cylindrical body by crushing a portion; an electrode feeding device that performs an electrode feeding operation for electric discharge machining; a transferring device that moves the cylindrical body along a predetermined wire electrode insertion path passing through the machining start hole; and a control device for setting the wire guide in a state in which the cylindrical body can penetrate when a feeding operation is performed, and the wire electrode is automatically set by pulling the wire electrode by the cylindrical body. It is in the point of being done.

(Function) When setting the wire electrode, when the wire electrode is fed out from the wire electrode supply device, the take-out device is activated and the cylindrical body is taken out from the holder, and the taken out cylindrical body is placed on the traveling path of the wire electrode. will be placed in Thereafter, the free end of the wire electrode is inserted into this cylindrical body, and a part of the cylindrical body is crushed, thereby fixing and connecting the two.

The cylindrical body is fed by an electrode feeding device in order to make a machining starting hole in the workpiece, and in addition, when a wire electrode is connected, it is fed by a transfer device so as to open the wire electrode. The wire electrode is set by pulling the wire.

(Example) FIG. 1 is a schematic diagram showing the main parts of a wire cut electrical discharge machining apparatus equipped with an automatic wire electrode setting device 1 according to the present invention. A wire electrode 7 from a wire electrode supply device 6 comprising a wire electrode bobbin 2 is supplied to the head 3 via a wire guide 4. The head 3 has a housing 80, and a feed screw 83 driven by a servo motor 82 is screwed into a support arm 81 of the housing 80, and the servo motor is driven by a servo control signal supplied from the control unit C/U. The drive control of the head 82 is performed, and the feeding operation of the head 3 is performed.

A pair of wire feed rollers 5, 5 driven by a motor M are disposed inside the head 3, and the wire electrode 7 fed into the head 3 by the wire feed rollers 5, 5 is passed through a guide member 70. The data is sent to an automatic setting device 80, which will be described later. A pair of drive rollers 30, 30 are provided at the lower end of the head 3.
and a first wire guide 10,
The wire electrode 7 is taken out from the head 3 via the first wire guide 10, enters the second wire guide 11 via a processing start hole 9c made in the workpiece 9 as described later, and is transferred to the conveyor belt 13, 1
The wire is fed into a wire collection box 15 by a wire conveying device 12 comprising 4.

A pipe, which is a tubular body, is fixed to the free end (connection end) of the wire electrode 7 supplied from the wire electrode supply device 6, and the wire electrode 7 is guided by this pipe, thereby forming the first wire guide 10. In order to ensure that the wire electrode 7 is inserted into the second wire guide 11, the automatic setting device 8 includes a holder 22 that can hold a plurality of pipes 21 for guiding the wire electrode 7, and a holder 22 that can hold a plurality of pipes 21 for guiding the wire electrode 7. The apparatus includes a pipe take-out device 23 that takes out the pipes 21 one by one and places them on the wire electrode passage between the wire electrode supply device 6 and the first wire guide 10. The pipe 21 taken out by the pipe take-out device 23 is shown by a chain line in FIG.
A connecting device 24 is provided for connecting a portion of the.

The coupling device 24 includes an arm 26 that moves forward and backward along its axial direction by a solenoid 25, and a pipe 2.
It consists of an arm 26 and a fixed block 27 disposed opposite to each other via 1, and when the solenoid 25 is energized by the control unit C/U, the arm 26 moves toward the fixed block 27, and the end of the pipe 21 21a is crushed. A guide member 70 for guiding the wire electrode 7 supplied from the wire electrode supply device 6 into the hollow portion of the pipe 21 is disposed above the end portion 21a of the pipe 21 taken out by the pipe takeout device 23. ing. This guide member 70 has a guide hole 70a in which the entrance side of the wire electrode 7 has a large diameter and the exit side has a small diameter. The free end of the wire electrode 7 is reliably connected to the end 21 of the pipe 21 when it is paid out by the rollers 5, 5.
It is sent into the hollow part of a. Control unit C/
U indicates that the solenoid 25 is activated at the timing when the free end of the wire electrode 7 is sent into the hollow part of the pipe 21.
energizes to crush the end 21a of the pipe 21,
Thereby, the pipe 21 and the wire electrode 7 can be fixed together.

The pipe 21 is made of an electrically conductive material, for example copper, and is connected to the wire as described above so that the pipe 21 can be used as an electrical discharge machining electrode for drilling a machining starting hole in the workpiece 9. By connecting the electrode 7, the two are also electrically connected. The wire cutting device 60 is composed of a cutter 61 and an actuator 62 that drives the cutter 61. When the actuator 62 is actuated by a signal from the control unit C/U, the lower end of the guide member 28 The wire electrode 7 coming out from is cut by the cutter 61.

The pipe take-out device 23 includes a pipe gripping section 28 for gripping and holding the pipe 21, and an actuator section 29 for moving the pipe gripping section 28 and performing pipe gripping operations. The actuator section 29 operates in response to a signal from the control unit C/U, advances the pipe gripping section 28 to approach the holder 22, takes out only one pipe 21, and grips the taken out pipe 21. At the same time, the pipe gripping section 28 is moved back to position the pipe 21 on the path of the wire electrode 7. The gripping operation of the pipe 21 by the pipe gripping section 28 is performed by the connecting device 2.
4, the connection between the pipe 21 and the wire electrode 7 is released, and as the wire electrode 7 is sent out by a pair of wire delivery rollers 5, 5, the pipe 21 is sent downward, and the pipe gripping part 28 is moved downward. A pair of drive rollers 30, 3 arranged below
0 to the first wire guide 10.

The first wire guide 10 is a casing in which insertion holes 31 and 32 are formed on the top and bottom for passing the pipe 21 and the wire electrode 7, and a machining fluid supply hole 33 for supplying machining fluid is formed on the side surface of the through holes 31 and 32. 3
It has 4. Inside the casing 34, a pair of fixed guide members 35, 36 are arranged at intervals in the passing direction of the wire electrode 7, and a pair of fixed guide members 35, 36 are arranged between these fixed guide members 35, 36, and A movement guide member 37 is provided so as to be moved forward and backward in directions perpendicular to the direction in which the wire electrode 7 passes (directions of arrows A and B).

As shown in FIG. 2, the fixed guide member 35,
36 has a notch 3 for guiding the wire electrode 7.
5a and 36a are formed respectively, and when the movable guide member 37 is advanced by the actuator 38 and positioned at the position shown by the dashed line, the respective notches 35a and 36b of the fixed guide members 35 and 36,
The wire electrode 7 can be guided by the notch 37b formed in the movement guide member 37. On the other hand, when the movement guide member 37 is moved backward in the direction of arrow B by the actuator 38 and reaches the position shown by the solid line, the notches 35a, 36a and 37a
The area of the guide path formed by this increases, which is necessary and sufficient for guiding the pipe 21. That is, by adjusting the position of the movement guide member 37 using the actuator 38, the first wire guide 10 can be put into at least a first state in which the pipe 21 is guided and a second state in which the wire electrode 7 is guided. can be realized.

The pipe 21 sent out by the driving rollers 30, 30 is guided by the first wire guide 10 in the first state, and is moved by a predetermined length to the first wire guide 10.
When the pipe 21 is fed out, the motor M ₂ that drives the drive roller 30 is stopped, and the pipe 21 starts machining the machining start hole. For this reason, a machining pulse is applied between the pipe 21 and the workpiece 9 from a machining pulse power source (not shown), and servo control for feeding the electrode necessary for drilling this hole is performed by the control unit C/U. and the servo motor 82. That is, after the pipe 21 is let out by a predetermined length from the first wire guide 10, the pipe 21
1 serves as a machining electrode fixed to the head 3, and the wire cut electric discharge machining apparatus functions only during this period as a drilling electric discharge machining apparatus using the pipe 21 as a rod-shaped machining electrode.

After the machining start hole 9c is formed in this way, the head 3 is moved back to its original position by the servo motor 82, and then the drive roller 30,
30 is again driven by motor M ₂ and pipe 2
1 is resumed, and the pipe 21 enters the second wire guide 11 via the processing start hole 9c. Here, since the machining start hole 9c is formed by the pipe 21, even if the diameter is small, the pipe 21 can be inserted into the machining start hole 9c without troublesome adjustments such as positioning. It can be inserted.

The second wire guide 11 also has exactly the same configuration as the first wire guide 10 described above, and accordingly, corresponding parts are given the same reference numerals and explanation thereof will be omitted.

First and second wire guides 1 in the first state
0, 11 and the pipe 21 sent out through the processing start hole 9c enters the wire conveyance device 12, is sandwiched between conveyor belts 13 and 14, and is conveyed into a wire collection box 15.

Next, the structure of the holder 22 and the pipe take-out device 23 will be explained in detail with reference to FIG. Holder 22
has a substantially L-shaped pipe holder 41, and the pipe holder 41 is attached to the main body block 43 by a hinge pin 42.
is hinged to. The main body block 43 and the hinge pin 42 are firmly fixed to a frame (not shown), and the pipe presser 41 is attached to the presser spring 4.
4 toward the main body block 43. The structure is such that a plurality of pipes 21 are held between the pipe holder 41 and the main body block 43 by the spring biasing force of the pipe holder 41 against the main body block 43. In order to prevent these clamped pipes 21 from escaping from the free end of the pipe holder 41, the free end of the pipe holder 41 is formed with a curved portion 45 that is slightly curved toward the opposite side.

The pipe holder 41 is also provided with a stop plate 46 for pressing the pipes other than the outermost pipe held by the curved portion 45 toward the main body block 43. is housed in a notch 47 formed in the pipe holder 41, and a stop plate 46 is held in place by a stop spring 47 (see FIG. 4) disposed between the stop plate 46 and the pipe holder 41. 41 and is biased by a spring. The spring force of the retaining spring 47 is such that the pipe holder 41 holds the pipe 2 as shown in FIG.
1, the stop plate 46
is set so that it is in close contact with the pipe holder 41.

On the other hand, the pipe take-out device 23 has a slider 51
and the hinge pin 5 fixed to the slider 51.
a pair of jaws 54, 54 hinged by 2 and for receiving the pipe 21 at its free end;
A movable intake holder 53 is formed therein, and a pipe gripping portion 28 is provided. The actuator section 29 includes a first actuator 29a for moving the slider 51 in the directions of arrows C and D, and a second actuator 29b for opening and closing the movable intake holder 53. The first actuator 29a is fixed to a frame (not shown),
The slider 51 connected to the first actuator 29a by an arm 55 can be moved by the first actuator 29a along a guide rail (not shown) in the directions of arrows C and D, thereby taking out the pipe 22 from the holder 22. and grasp it.
This removed pipe can be positioned at a predetermined position.

4a to 4d, the pipe removal device 2
3 illustrates the operation of taking out only one pipe 21 from the holder 22. To explain the operation of taking out the pipe with reference to FIGS. 3 and 4, first, the movable intake holder 53 is opened by the second actuator 29b (FIG. 4a), and then the first
The actuator 29a moves the slider 51 in the direction of arrow C.
When the notch 51a formed in the portion of the slider 51 facing the holder 22 comes into a predetermined fit with the main body block 43 (FIG. 4b), the second actuator 29b is activated. The movable intake holder 53 is closed, and the pair of jaws 5
4, 54 and the slider 51, the outermost pipe 21 is taken in. Next, when the first actuator 29a operates to move the slider 51 backward, the pipe holder 41 is opened against the spring force of the pressing spring 44, and the pipe 21 is taken out. At this time, although the pipe retainer 41 is opened due to the action of the stop plate 46 and the stop spring 47, the remaining three pipes are held against the main body block 43 by the stop plate 46. These pipes are therefore held tightly (see Figure 4c).
At this time, the remaining three pipes are pushed outward by the feed spring 48, so when the pipe holder 41 is closed again, the pipe 21 is in the fourth position.
In the figure, it is moved towards the right hand side, and is ready for the next pipe removal operation.

Next, the operation of the automatic wire electrode setting device 1 will be explained with reference to FIG. When the tip of the wire electrode 7 fed out from the wire electrode device 6 is guided by the guide member 28 and reaches the vicinity of the coupling device 24, the driving of the motor _M1 is stopped and the wire cutting device 60 is activated, and the wire electrode 7 is cut. A cut is made. Next, the pipe take-out device 23 is activated to take out the pipe 21 from the holder 22, and the taken-out pipe 21 is positioned at the position shown in FIG. As a result, the end 21a of the pipe 21
and the connecting end of the wire electrode 7 face each other, and the motor is connected again.
When M ₁ is driven, the motor M is stopped when the connecting end of the wire electrode 7 fully enters the hollow portion of the end 21 a of the pipe 21 . Next, the connecting device 24 is activated to crush the end portion 21a of the pipe 21, thereby fixing the pipe 21 and the wire electrode 7.

When the connection work between the pipe 21 and the wire electrode 7 is completed in this way, the second actuator 29b
is actuated to release the clamping state of the pipe 21 by the pipe gripping section 28, and the motor _M1 is driven again to feed the pipe 21 toward the workpiece 9. At this time, the first and second wire guides 10,
11 are in the first state, therefore, the pipe 2 sent out by the drive rollers 30, 30
1 is guided by the first wire guide, and the workpiece 9
sent towards. When the pipe 21 protrudes from the head 3 by a predetermined length, the driving of the motor _M2 is stopped and the drilling operation of the machining start hole using the pipe 21 is started. Once the machining start hole 9c is formed, the motor _M2 starts operating, and the pipe 21 is sent to the second wire guide 11 through the machining start hole 9c. The pipe 21 is guided by the second wire guide 11 and the wire conveying device 12
taken over by. As a result, the wire electrode 7 is guided by the pipe 21 having the required rigidity and the first
Since the wire electrodes are inserted through the second wire guides 10, 11 and the processing start hole 9c, problems such as buckling do not occur at all, and the wire electrodes can be automatically set with high reliability.

(Effects) According to the present invention, as described above, a machining start hole is formed in a workpiece using a cylindrical body, and a wire electrode is placed in a required wire electrode running path passing through the machining start hole thus formed. When setting the wire electrode, place the free end of the wire electrode into the cylindrical body and crush a part of the cylindrical body to fix the wire electrode to the cylindrical body, and then use the cylindrical body to guide the wire electrode. Since it is configured to be set in the required travel path, there is no problem of buckling of the wire electrode within the guide tube, and there is no need to bother with inserting a large number of wire bodies into the machining start hole in advance. The special effect is that automatic setting of wire electrodes can be easily and reliably performed without causing any problems, even with extremely small diameter wire electrodes, and extremely reliable fully automatic operation can be performed. play.

[Brief explanation of the drawing]

Fig. 1 is a schematic configuration diagram showing an embodiment of the present invention, Fig. 2 is a perspective view for explaining the structure of the wire guide shown in Fig. 1, and Fig. 3 is a holder and pipe extraction device shown in Fig. 1. The enlarged perspective views of FIGS. 4a to 4d are operational explanatory diagrams for explaining the operation of taking out the pipe from the holder by the pipe taking out device. 1... Wire electrode automatic setting device, 3... Head,
6... Wire electrode supply device, 7... Wire electrode, 8...
Automatic setting device, 9... Workpiece, 9c... Machining start hole, 10... First wire guide, 11... Second wire guide, 12... Wire conveyance device, 21... Pipe,
22... Holder, 23... Pipe take-out device, 24... Connecting device, 82... Servo motor, C/U... Control unit.

Claims (1)

[Claims] 1. A machining start hole is formed in a workpiece using a conductive cylindrical body by electrical discharge machining, and a wire electrode supplied from a supply reel is provided near the machining start hole and the workpiece. In an automatic wire electrode setting method for a wire cut electrical discharge machining apparatus, the free end of the wire electrode is engaged inside the cylindrical body. After the insertion, the wire electrode is fixed to the cylindrical body by crushing a part of the cylindrical body, and the wire electrode is pulled by the cylindrical body to connect the wire electrode to the desired wire electrode. An automatic method for setting a wire electrode for a wire cut electrical discharge machining device, which method comprises setting the electrode on a running path. 2. A wire electrode supply device that supplies a wire electrode, a first wire guide that guides the wire electrode supplied from the wire electrode supply device, and a second wire guide that is disposed opposite to the first wire guide with the workpiece interposed therebetween.
In an automatic wire electrode setting device for a wire cut electric discharge machining machine, which is equipped with a wire guide and a take-off device for taking out the wire electrode taken out through the second wire guide, a cylindrical body that can be used as an electrode for electric discharge machining is provided. A holder for holding at least one wire electrode; and prior to setting the wire electrode, a cylindrical body inside the holder is removed and the cylindrical body is placed on the wire electrode passage between the wire electrode supply device and the first wire guide. a take-out device for placing the body, and a free end of the wire electrode inserted into the cylindrical body placed by the take-out device, and then crushing a part of the cylindrical body to remove the wire electrode. a coupling device that is fixed to the cylindrical body; and an electrode that provides an electrode feeding motion to the cylindrical body for electric discharge machining in order to drill a machining start hole in the workpiece by electric discharge machining using the cylindrical body. a feeding device, a feeding device that feeds the cylindrical body along a predetermined wire electrode insertion path passing through the processing start hole, and a wire guide when the feeding device performs a required feeding operation of the cylindrical body. a control device for setting the wire electrode in a state in which the cylindrical body can penetrate, and the wire electrode is automatically set by pulling the wire electrode by the cylindrical body. Automatic wire electrode setting device for equipment.