JPH0615125B2 - Wire electrode supply device for wire electric discharge machine - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wire electric discharge machine, and more particularly to improvement of a device for automatically feeding wire electrodes.

[Conventional technology]

FIG. 3 is a schematic view showing a conventional wire electric discharge machine with an automatic wire feeder. In the figure, (1) is a wire electrode, and a motor (3a) of a wire electrode bobbin mounting means (2).
It is unwound from a bobbin (3b) that is driven to rotate by.

A brake roller (4) is directly connected to the brake (5) and applies a tension to the wire electrode (1). (6) is a guide roller for changing the traveling direction of the wire electrode (1), (8) is a pulley, and (9) is a disconnection detector as a disconnection detection means for the wire electrode (1) directly connected to the pulley (8). (For example, an encoder or the like).

(10) is a wire electrode feeding means, which is a capstan roller (13) directly connected to the motor (12) fixed to the housing (11) and a capstan roller (13) by a compression spring (14).
It is composed of a pinch roller (15) that presses and holds the wire electrode (1) on the pinch roller (15), which is a fulcrum (16).
The swing arm (1
It is rotatably supported by 7).

(18) is a pipe guide, and a die guide (18
The wire electrode (1) is inserted through and guided to the inside, and is fixed to the wire electrode feeding means (10). (1
9) is a moving means for moving the wire electrode feeding means (10) up and down, a guide rod (21) vertically attached to the attachment base (20) and a motor provided at the upper end of the guide rod. (22) and a feed screw (23) mounted on the mounting base in parallel with the guide rod and driven by the motor. The housing (11) is guided by the ball guide (24) into the guide rod (21). Nuts that are slidably supported on and screwed onto the feed screw (23)
It is held by (25).

Reference numeral (26) is an upper guide unit for the wire electrode (1), which holds the pipe guide (18) in a predetermined position and also a nozzle.
From (27), a machining fluid is jetted and supplied from a machining fluid supply device (not shown) to the machining area (29) of the workpiece (28).

Reference numeral (30) is a lower guide unit for the wire electrode (1), which holds the lower guide (31) having a die guide (31a) at its tip at a predetermined position and feeds electricity (32) to the wire electrode (1).
It is fixedly held at the position where it comes into contact with.

(33) is a wire electrode collecting mechanism, which comprises a pair of pressure-contacted rollers (34a), (34b) and a belt (35) wound around the rollers.
It is composed of a) and (35b). (36) is a motor directly connected to the roller (34b).

(37) is a cutting mechanism for the wire electrode (1) supported above the upper guide unit (26), which is rotated 180 ° by the motor (38) and advances the cutter (40) by the cylinder (39). ， It is configured to be able to move backward.

Next, the operation will be described. Workpiece with wire electrode (1)
When starting machining by penetrating the initial hole (28a) of (28) and feeding downward, use the motor (22) to feed the screw (23)
When is rotated, the housing (11), which is given a linear motion force through the nut (25), moves downward along the guide rod (21), and the pipe guide (18) passes through the initial hole (28a). Is driven to above the lower guide (31). At this time, the wire electrode (1) remains pressed and held by the wire electrode feeding means (10) and the capstan roller (13) by the pinch roller (15) which receives the spring force of the compression spring (14). .

Next, by rotating the motor (12), the wire electrode (1) pressed and held by the capstan roller (13) and the pinch roller (15) is sent to the workpiece (28) side,
By operating the motor (36) of the wire electrode recovery mechanism (33), the wire electrode (1) sent out is transferred to the belts (35a), (3).
5b) Hold it between the two and convey it, and discharge it outside the equipment.

When the wire electrode (1) is discharged, the motor (22) is rotated in the opposite direction, the pipe guide (18) is raised and returned to a predetermined processing position, and the automatic supply of the wire electrode (1) is completed.

Next, while applying a voltage between the wire electrode (1) and the workpiece (28) from a machining power source (not shown) through the power supply (32), the wire electrode (1) is driven by a driving device (not shown). And the workpiece (28) are relatively driven in the X-axis and Y-axis directions to cut into a desired shape.

If the wire electrode (1) is broken during the above processing, first,
The motor (22) is activated to disconnect the pipe guide (18).
Raise above (37). At this time, the wire electrode (1) is held between the capstan roller (13) and the pinch roller (15) of the wire electrode feeding means (9), and the pipe guide (18).
There is no way out. In addition, the surplus wire electrode generated when the pipe guide is raised is the wire electrode bobbin mounting means (2).
The bobbin (3b) is rewound by reversing the rotation of the bobbin (3b) by the motor (3a) provided in the.

Next, the motor (38) is rotated and the cutting mechanism (37) is rotated 180 ° to set the wire electrode cutting position. After that, the cutter (40) is advanced by the cylinder (39) to cut and remove the portion damaged by the discharge of the wire electrode (1).

Next, the cutting mechanism (37) and the pipe guide (18) are returned to the predetermined positions by the operation reverse to the above operation. Then wire electrode
Since the automatic supply of (1) has been described above, it will be omitted.

During processing, the wire electrode (1) is subjected to the assertive force (about 1000 to 2500 g) by the brake (5) and the pre-tension (100) by forcibly rotating the motor (2) in the opposite direction.
(About 300 g) is controlled by a control device (not shown).

[Problems to be Solved by the Invention]

Since the wire electrode supply device of the conventional wire electric discharge machine is configured as described above, when the wire electrode is fed by the wire electrode feeding means, the pressing force of the pinch roller is
It is constant regardless of the type and diameter of the wire electrode, and the set value must be the lowest value for all wire electrodes to prevent curling, buckling deformation and cutting with the wire electrode. This is a factor that reduces the reliability of the delivery means. Further, during processing, there is a problem that it is deformed by receiving the pressing force of the pinch roller, which causes a reduction in processing accuracy.

The present invention has been made in order to solve the above problems, and the type and diameter of the wire electrode to be fed, or the pressing force of the pinch roller is switched depending on whether the wire electrode is fed or not. It is possible to obtain a wire electrode supply device of a wire electric discharge machine that improves the reliability of wire electrode feeding due to an increase in the feeding force and that does not cause deformation of the wire electrode due to an external force during machining and can perform highly accurate machining. To aim.

[Means for Solving the Problems]

A wire electrode supply device for a wire electric discharge machine according to the present invention includes a wire electrode feeding unit that presses and holds a wire electrode against a capstan roller by a pinch roller, and a wire electrode feeding unit that sends out the wire electrode, and a pressing force of the pinch roller is adjusted in multiple stages. The present invention is provided with a possible multi-stage switching means and a control means for controlling the switching operation of the pressing force of the pinch roller in the multi-stage switching means.

[Work]

The wire electrode supply device of the wire electric discharge machining apparatus according to the present invention, while feeding the wire electrode, applies a pressing force to the capstan roller of the wire electrode by the pinch roller depending on the type and diameter of the wire electrode to be fed or machining or non-machining. By switching, the wire electrode feeding force is increased, the reliability of wire electrode feeding is improved, external force does not act on the wire electrode during machining, and the deterioration of machining accuracy due to deformation of the wire electrode is prevented. To do.

Example of Invention

An embodiment of the present invention will be described below with reference to the drawings. In FIG. 1 in which the same parts as those in FIG.
(41) is a pinch roller provided in the wire electrode feeding means (10)
Pressing multi-stage switching means for switching the pressing of the wire electrode (1) to the capstan roller (13) by (15), (42) is the type and diameter of the wire electrode to be fed, or the above pressing during processing or non-processing It is a control means for controlling the multistage switching means.

FIG. 2 is a sectional view showing a wire feeding means (10) provided with the pressing multistage switching means (41) and a circuit diagram showing a control means (42) for controlling the pressing multistage switching means. In the figure, (43) is a regulator that controls the air pressure to a constant value, and (4)
4) is a pressure gauge showing a constant value of the regulator (43), (4
5) is a two-way solenoid valve that opens and closes the air circuit, (46) is a check valve that regulates the direction of air flow, and (57) is a housing.
A cylinder fixed to (11) and its piston rod
The tip of (58) is fixed to one end of the swing arm (17).

Next, the operation will be described. The automatic supply operation and processing of the wire electrode (1) are the same as those of the conventional example shown in FIG.
The automatic supply operation of (1) will be described. The pressing force for pressing and holding the wire electrode (1) against the capstan roller (12) by the pinch roller (15) of the wire electrode feeding means (10) is determined by the pressure of air supplied to the cylinder (57). That is, the thrust acts on the piston rod (58) by supplying the air to the cylinder (57), and the thrust is determined by the air pressure and the pressure receiving area of the piston rod (58) that receives the air pressure. (Thrust = Air pressure x Pressure receiving area) The piston rod
The thrust acting on (53) acts on the oscillating arm (17) rotatably supported on the housing (11) by the fulcrum (16), and the oscillating arm (17) is rotated counterclockwise, so that the cap is rotated. Stan roller (1
The pinch roller (15) pressing force is applied to 2).

Before processing, depending on the type and diameter of the wire electrode used, the air pressure is regulated so that the pressing force of the pinch roller that gives the maximum feeding force without curling, buckling or cutting of the wire electrode during feeding the wire electrode ( 43) by pressure gauge (44)
Adjust each while watching. (Air circuit A, B) or the wire electrode (1) which is not deformed by the pressing force of the pinch roller (15) during processing and is pressed by the pinch roller (15) by the pre-tension during cutting ( Adjust the regulator (43) of one air circuit so that 1) has the minimum pressing force of the pinch roller (15) so that it will not be wound up on the slip bobbin. (Air circuit C) Wire electrode (1) during electric discharge machining after completion of the above adjustment
Is continuously supplied so that the new part faces the work piece (28), and the pressing force of the pinch roller (15) of the wire electrode feeding means (10) is set by the solenoid valves A, B, D. When the solenoid valve C is closed and the solenoid valve C is open, the pressing force is the pressure set by the air circuit C.

In this state, if the wire electrode is broken, the same operation as in the case of the broken wire described in the conventional example is performed, and when the wire electrode (1) is fed by the wire electrode feeding means (10), the solenoid valve D is It opens, the internal pressure of the cylinder (57) is released, and then only the solenoid valve of the air circuit (for example, A) set by the type and diameter of the wire electrode to be fed is opened and the remaining solenoid valves are closed. The pressing force of the pinch roller (15) at that time is the pressing force set by the air circuit A.
When the automatic supply of the wire electrode (1) is completed in the above state and the machining is started again, the solenoid valve D opens to release the internal pressure of the cylinder (57) as in the above operation, and then the solenoid valve C remains open. When the solenoid valve is closed, the pinch roller (15) is pressed by the pressure set in the air circuit C, and the machining is started.

In the above embodiment, the pressing multi-stage switching means (41) has a piston rod by the air pressure flowing into the cylinder (57).
The case where the pressing force of the pinch roller (15) is changed by the thrust of (58) has been described. The pinch roller shown in FIG.
Even if the attachment length of the compression spring (14) for applying the pressing force to the (15) is changed by the cylinder to change the pressing force of the pinch roller (15), the same effect as in the above embodiment can be obtained.

〔The invention's effect〕

As described above, according to the present invention, during feeding of the wire electrode,
Since it is configured to switch the pressing force of the wire electrode to the capstan roller by the pinch roller depending on the type and diameter of the wire electrode to be fed and during processing and non-processing,
The wire electrode feeding force is increased, the reliability of wire electrode feeding is improved, and the wire electrode is not deformed due to the action of an external force during machining, so that it is possible to perform highly accurate wire electric discharge machining.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing the configuration of a wire electric discharge machining apparatus according to an embodiment of the present invention, FIG. 2 is a detailed configuration diagram of a wire feeding means and an air control circuit in this apparatus, and FIG. 3 is a conventional wire. It is a schematic diagram showing the composition of an electric discharge machine. In the figure, (1) is a wire electrode, (10) is a wire electrode feeding means, (41) is a pressing multi-stage switching means, and (42) is a control means. In the drawings, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Claims] 1. An upper wire guide means for slidably supporting a wire electrode above a work piece, a lower wire guide means for slidably supporting a wire electrode below a work piece, and a wire electrode by a focus roller. A wire electrode supply means for pressing and holding the wire electrode to the capstan roller, and a guide for guiding the wire electrode sent to the upper wire guide means, the initial hole of the workpiece and the lower wire guide means. Means, a pressing multistage switching means for adjusting the pressing force of the pinch roller of the wire electrode supplying means in multiple stages, and a control means for controlling the switching operation of the pressing force of the pinch roller in the pressing multistage switching means. A wire electrode supply device for a characteristic wire electric discharge machine.