JPH09207127A - Roller abrasion detector of wire saw - Google Patents

Abstract

PROBLEM TO BE SOLVED: To keep good and highly accurate cutting at the time of usual cutting work by providing a wire material cutting detection means detecting that a detection wire material comes into contact with a running wire to be cut when a roller is abraded to detect the abrasion of the roller. SOLUTION: A roller abrasion detection apparatus 1 is equipped with the detection wire material S provided at a position where the wire Y guided by a roller 2 runs when the roller 2 is abraded by predetermined quantity under tension in the direction crossing the wire Y and a wire material cutting detection means 3 detecting that the detection wire material S comes into contact with a running wire Y to be cut at the time of the abrasion of the roller 2 to detect the abrasion of the roller 2. At the time of usual processing work, since the detection wire material S does not come into contact with the wire Y and comes into contact with the wire Y only when the roller 2 is abraded by predetermined quantity, no effect is exerted on the wire Y itself. Further, the abrasion of the roller 2 most severely abraded to generate a slip first among a plurality of rollers is detected at first and the slip of the wire Y is prevented in the whole of the apparatus.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention detects when a roller for guiding a wire reaches a predetermined amount in a wire saw for cutting a highly hard brittle material such as a semiconductor material, a magnetic material, or a ceramics with a wire. Roller wear detector.

[0002]

2. Description of the Related Art A wire saw moves a wire stretched between a plurality of rollers in a certain direction at a predetermined speed by a wire running device, while pressing a member to be cut such as a semiconductor ingot or ceramics onto the wire by a pressing device. It is known to press the cutting member to supply a working liquid containing abrasive grains to the cutting member of the member to be cut to cut the member to be cut, and to cut the member by alternately running wires in opposite directions. .

In the roller, since a wire formed of a steel wire is generally stretched in a state where the above-mentioned abrasive grains are adhered, a groove for guiding the wire gradually wears and becomes deeper. However, as the roller, one having urethane formed on the outer peripheral surface of the metal center part is used,
When the wear becomes severe, the traveling wire reaches the central portion of the metal and slips, which causes a problem that a precise working operation cannot be performed.

As a means for solving this, for example, Japanese Patent Laid-Open No. 7-
In Japanese Patent No. 266213, one terminal of a power source is connected to a conductive wire, and a conductive detection bar is provided at a position where the wire comes into contact when the roller wears.
A technique for judging the wear of the roller by a voltage detecting means between the other terminal of the power source and the detecting bar is introduced.

[0005]

However, the above-mentioned conventional means for solving the problems still have the following problems.
That is, in order to keep one terminal of the power source always connected to the wire, it is necessary to bring the carbon brush or the like into contact with the traveling wire, so that dust such as carbon adheres to the wire and There was a risk that the adhesion would deteriorate.

The present invention has been made in view of the above problems, and provides a roller wear detecting device capable of detecting the wear of a roll without lowering the adhesion of the working liquid to the wire in the wire saw. The purpose is to

[0007]

The present invention has the following features to attain the object mentioned above. That is, in the roller saw detecting device for a wire saw according to claim 1, the member to be cut is relatively pressed against the wire while being guided by the roller and running at a predetermined speed while being stretched. A roller wear detecting device for detecting that a roller wear in a wire saw for cutting a workpiece reaches a predetermined amount, the wire being guided to a position where the wire guided by the roller travels when the roller wears a predetermined amount. Detection of wire rods stretched in the direction intersecting with the wire, and when the roller wears, the detection wire rod detects the wear of the roller by detecting that the wire is in contact with the running wire and is cut And a technique comprising a means is employed.

In this roller saw detecting device for a wire saw, a detecting wire is stretched in a direction intersecting with the wire guided by the roller when the roller is worn by a predetermined amount. When the roller wears by a predetermined amount, the detection wire rod comes into contact with the running wire and is cut, and the wire rod cutting detection means detects the cutting of the detection wire rod and detects the wear of the roller. Therefore, the wire for detection does not come into contact with the wire during normal processing work, and does not affect the wire itself.

According to a second aspect of the present invention, there is provided a roller wear detecting device for a wire saw according to the first aspect, wherein the wire has abrasive grains attached thereto while the wire is running, and the roller has at least the abrasive grains attached thereto. The technology that is a roller that guides the wire immediately after being applied is adopted.

In this wire saw roller wear detecting device, since it is applied to the roller that guides the wire immediately after the abrasive grains are adhered, the wear of the roller that causes the most slip and the first slip among the plurality of rollers of the entire device. Is detected first, and wire slip is prevented in the entire device.

According to a third aspect of the present invention, there is provided a roller wear detecting device for a wire saw according to the first or second aspect, wherein the detecting wire has conductivity and the wire cutting detecting means has the detecting means. A technique including a wire rod continuity detection unit that detects an electrical continuity state of the wire rod for use is adopted.

In this wire saw roller wear detecting device, since the wire rod continuity detecting portion detects the electrically conductive state of the conductive wire rod for detection, when the wear of the roller does not reach the predetermined amount, the wire is used for detecting. A good conduction state of the detection wire is electrically detected by the wire conduction detector without contacting the wire, but when the wear reaches a predetermined amount, that is, the wire contacts the detection wire and When the wire is cut, the electric resistance of the wire for detection becomes infinity, and it is detected by the wire continuity detection unit that the wire for detection is electrically disconnected. Therefore, whether or not the wear of the roller has reached a predetermined amount is detected by the conduction state of the detection wire.

According to a fourth aspect of the present invention, there is provided a roller wear detecting device for a wire saw according to the first or second aspect, wherein the wire rod cutting detecting means is a switch in which one end of the detecting wire rod is connected and restrained. A limit switch having a section and a disconnection signal detection section for detecting a signal from the limit switch.
A technique is adopted in which when the detection wire is cut, the switch is released from the detection wire to send a signal to the disconnection signal detection unit.

In this wire saw roller wear detecting device, since the switch portion of the limit switch is connected to the detecting wire rod, when the traveling wire gradually wears the roller, the wire becomes the detecting wire rod at a predetermined position. When it abuts and disconnects it, the restrained switch unit is released and the limit switch sends a signal to the disconnection signal detection unit. That is, it is detected by the signal that the wear of the roller has reached a predetermined amount.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION A first embodiment of the present invention will be described below with reference to FIGS. In these drawings, reference numeral S is a detection wire, Y is a wire, 1 is a roller wear detection device of a wire saw, 2 is a roller, and 3 is a wire cutting detection means.

The roller saw detection device 1 for a wire saw according to the first embodiment guides a wire Y formed of a steel wire by a roller 2 and runs at a predetermined speed while being stretched, while cutting a semiconductor ingot or the like. The member is pressed relatively to the wire Y to detect that the wear of the roller 2 in the wire saw for cutting the member to be cut reaches a predetermined amount.

As shown in FIGS. 1 and 2, the roller wear detecting device 1 crosses the wire Y at a position where the wire Y guided by the roller 2 travels when the roller 2 wears by a predetermined amount. Wire rod cutting for detecting wear of the roller 2 by detecting that the wire rod S for detection stretched in the direction and the wire rod S for detection contact with the wire Y in the running state when the roller 2 is worn The detection means 3 is provided.

The roller 2 is a disk-shaped central portion 2 made of metal.
a and a urethane portion 2b formed on the outer peripheral surface of the metal central portion 2a, the axis of which is the same as that of the roller support shaft 5 fixed to the inner wall 4 of the wire saw with a horizontal axis. It is rotatably supported. Further, a groove 2c is formed on the outer peripheral surface of the urethane portion 2b so as to guide the wire Y along the outer peripheral surface so as to be in a stretched state. Note that the wire Y has abrasive particles attached thereto during traveling, and the roller 2 guides the wire Y immediately after the abrasive particles have been attached.

The detection wire S is, for example, a conductive thin wire such as a copper wire, and has a U-shape whose base end is fixed to the inner wall 4 and which is arranged in parallel with the roller support shaft 5. It is provided in a stretched state between the base end and the tip of the wire rod support member 6. The wire Y is positioned between the base end and the tip of the wire rod support member 6, and the distance between the wire S for detection and the wire Y is set to be smaller than the distance from the metal central portion 2a to the groove 2c. Has been done. Therefore, it is necessary to detect the wear of the roller 2 by a predetermined amount, that is, the urethane portion 2
The wire S for detection is set at a position where it comes into contact with the wire Y immediately before b is worn by the wire Y and reaches the central portion 2a made of metal.

The wire cutting detection means 3 is a wire S for detection.
A power supply 7 having terminals electrically connected to both ends of
A resistor 8 and a resistance meter 9 electrically connected are provided in the middle of a circuit connecting the power source 7 and the detection wire rod S. The resistance meter 9 measures the electrical resistance of the detection wire rod S.

Next, a method for detecting wear of the roller 2 in the roller wear detecting apparatus 1 of the first embodiment will be described.

First, when a constant voltage is applied to the detection wire rod S by the power source 7, the resistance meter 9 detects a constant resistance value. In this state, when the wire Y is run to perform a working operation, the urethane portion 2b of the roller 2 is gradually abraded and the groove 2c is deepened in a state where the abrasive particles contained in the working liquid adhere to the wire Y. As it goes, it gradually moves toward the inside and toward the detection wire rod S. However, roller 2
Until the wear of the wire reaches a predetermined amount, the wire Y and the detection wire S do not come into contact with each other, and the resistance meter 9 detects the above-mentioned constant resistance value, and the good conduction state of the detection wire S is detected. .

When the wear of the roller 2 progresses to reach a predetermined amount, the wire Y contacts the detection wire S and cuts the detection wire S. At this time, the electric resistance of the detection wire rod S detected by the resistance meter 9 becomes infinite, and it is detected that the detection wire rod S is electrically disconnected. Therefore, whether or not the wear of the roller 2 reaches a predetermined amount is detected by the conduction state of the detection wire rod S. When the resistance meter 9 detects the non-conducting state of the detection wire S, a signal is further transmitted from the resistance meter 9 to the control unit of the wire saw so that the traveling of the wire Y is stopped.

In this roller wear detecting device 1, the wire S for detection does not contact the wire Y during normal working operation, but only when the roller 2 is worn by a predetermined amount, the wire Y is detected.
It does not affect itself. Further, since the wear of the roller 2 that guides the wire Y immediately after the abrasive grains are attached is detected, the wear of the roller 2 that causes the first slip and is the most worn out of the plurality of rollers of the entire apparatus is detected first. As a result, slippage of the wire Y is prevented in the entire device.

Next, a second embodiment of the present invention will be described with reference to FIG. In these drawings, reference numeral 10 is a roll wear detection device, 11 is a wire rod cutting detection means, 12 is a limit switch, and 13 is a cutting signal detection unit.

The difference between the second form and the first form is that the second form
Unlike the wire rod cutting detection unit 3 in the first embodiment, the wire rod cutting detection unit 11 of the roll wear detection device 10 in the first embodiment has a pin shape in which one end of the detection wire S is connected and constrained, as shown in FIG. The point is that the limit switch 12 having the switch section 12a and the disconnection signal detection section 13 for detecting a signal from the limit switch 12 are provided.

That is, in the roll wear detecting device 10, when the roller 2 wears and the wire Y cuts the detection wire rod S, the switch portion 12a is released from the detection wire rod S, that is, the switch portion 12a. By moving the tip toward the inner wall 4 (in the direction of the arrow in the figure), the limit switch 12
The contact inside is switched, and a signal is transmitted from the limit switch 12 to the disconnection signal detection unit 13 electrically connected, so that it can be detected that the roller 2 is worn by a predetermined amount. The disconnection signal detection unit 13 is set to further transmit a signal to the control unit of the wire saw to stop the traveling of the wire Y when the above signal from the limit switch 12 is received.

In this roll wear detecting device 10, it is not necessary to use a conductive wire as the wire S for detection, and the wire S for detection made of a material such as nylon having high corrosion resistance is used instead of metal. be able to.

As a means for detecting that the wire has moved a predetermined amount due to wear of the roller, an optical (for example,
A photosensor can detect a wire) or a magnetic means (for example, a proximity switch can detect a wire) can be considered, but it is difficult for these detection means to accurately detect a thin wire. Highly accurate sensors are required. On the other hand, in each of the above-described embodiments, it is possible to reliably detect that the roller 2 is worn by a predetermined amount with a simple structure.

Further, in each of the above-mentioned embodiments, the present invention is applied to a so-called guide roller in which one groove 2c is formed as a roller, but it may be applied to another roller for guiding a wire. For example, it may be applied to a cylindrical groove roller in which a plurality of grooves are formed on the outer peripheral surface and a wire is guided in each groove.

[0031]

According to the present invention, the following effects can be obtained. (1) In the wire saw roller wear detecting device according to the first aspect, since the detection wire is stretched at a position where the wire travels when the roller wears by a predetermined amount, the roller wears by a predetermined amount. Sometimes the detection wire is cut and the wear of the roller can be detected. Therefore, the wire for detection does not come into contact with the wire during normal processing work, and the wire itself is not affected, and good and highly accurate cutting can be maintained.

(2) According to the roller wear detecting device for a wire saw according to the second aspect, since it is applied to the roller for guiding the wire immediately after the abrasive grains are adhered, the wear of the plurality of rollers of the entire device is the highest. The wear of the roller, which causes a severe first slip, is detected first and the wire slip can be prevented in the entire apparatus.

(3) In the wire-saw roller wear detecting device according to the third aspect of the invention, since the wire rod continuity detecting portion detects the electrically conductive state of the detecting wire rod having conductivity, the wear reaches a predetermined amount. When the wire cuts the detection wire rod, the wire rod continuity detection unit can electrically detect that the detection wire rod is in a non-conductive state, and can detect that the wear of the roller has reached a predetermined amount. . Therefore, a simple and highly accurate detection device can be obtained.

(4) According to the wire wear roller wear detecting device of the fourth aspect, since the switch portion of the limit switch is connected to the detecting wire material, the wire cuts the detecting wire material when the roller wears by a predetermined amount. Then, the wear of the roller can be detected by opening the restrained switch portion. Therefore, a wire having high corrosion resistance can be used as the wire for detection without being limited to characteristics such as conductivity.

[Brief description of drawings]

FIG. 1 is a schematic front view showing a first embodiment of a roller wear detection device for a wire saw according to the present invention.

FIG. 2 is a schematic side view showing a first embodiment of a roller wear detection device for a wire saw according to the present invention.

FIG. 3 is a schematic side view showing a second embodiment of the roller wear detection device for a wire saw according to the present invention.

[Explanation of symbols]

 1, 10 Roller wear detection device 2 Roller 3, 11 Wire rod cutting detection means 7 Power supply 8 Resistor 9 Resistance meter 12 Limit switch 13 Cutting signal detection unit S Detection wire Y wire

Claims (4)

[Claims] 1. Wear of a roller in a wire saw for cutting a member to be cut by relatively pressing the member to be cut against the wire while the wire is guided by the roller and run at a predetermined speed while being stretched. A roller wear detecting device for detecting that a predetermined amount has been reached, the detection being stretched in a direction crossing the wire at a position where a wire guided by the roller travels when the roller wears by a predetermined amount. A wire rod and a wire rod cutting detection unit that detects wear of the roller by detecting that the wire rod for detection comes into contact with a running wire and is cut when the roller wears. Wire saw roller wear detector. 2. The roller wear detection device for a wire saw according to claim 1, wherein the wire has abrasive particles attached thereto during traveling, and the roller guides the wire at least immediately after the abrasive particles are attached. A roller wear detection device for a wire saw. 3. The roller saw detecting device for a wire saw according to claim 1, wherein the detection wire has conductivity, and the wire cutting detection means detects an electrically conductive state of the detection wire. An apparatus for detecting wear of a roller of a wire saw, comprising: 4. The roller saw detection device for a wire saw according to claim 1, wherein the wire rod cutting detection means includes a limit switch having a switch portion to which one end of the detection wire rod is connected and restrained, and the limit switch. The limit switch includes a disconnection signal detection unit that detects a signal from the switch, and the limit switch provides the disconnection signal detection unit with the switch unit being released from the detection wire rod when the detection wire rod is disconnected. A roller wear detection device for a wire saw, which transmits a signal.