JP3664354B2 - Wire saw - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to a wire saw, and more particularly, to a wire saw capable of automatically winding a wire almost all over its route.
[0002]
[Prior art]
  A wire saw travels reciprocally while continuously supplying a certain amount of slurry-like abrasive liquid containing loose abrasive grains (hereinafter sometimes simply referred to as abrasive grains) in wrapping oil to an ingot made of single crystal silicon or the like. This is a machine that presses an ingot relatively to a wire row and cuts it into a number of wafers by its grinding action.
  The wire of a wire saw is usually wound from a feeding reel, passed through a plurality of guide pulleys, wound around a plurality of grooved rollers separated from each other, and then passed through another plurality of guide pulleys. It is a route that is wound around the take-up reel.
[0003]
  By the way, the winding of the wire in the wire saw is usually performed manually by an operator. However, for example, the winding work around the groove roller or the like usually requires the wire to be wound 100 times or more, which is troublesome.
  Therefore, as a conventional means for solving this problem, for example, a “wire winding device” described in Japanese Patent Publication No. 4-4095 is known.
  This conventional apparatus is a dedicated apparatus for winding a wire around a groove roller. That is, a grooved roller unit that can be attached to and detached from the wire saw and that pivotally supports a plurality of grooved rollers between the face plates is intermittently rotated in the circumferential direction, and a wire winding reel and a wire guide pulley are mounted in synchronization with this. The traveling body is intermittently moved along the rotation main shaft of the groove roller unit so that the wire from the wire winding reel is wound while being sequentially transferred to the groove position of each groove roller via the wire guide pulley. It can be built.
[0004]
[Problems to be solved by the invention]
  However, this conventional wire winding apparatus has the following problems.
  That is, (1) This wire winding device is dedicated to winding around the groove roller, and cannot wind up the wire over the entire wire saw. Therefore, usually the remaining part is manually wound. However, many guide pulleys are scattered in the remaining area. Therefore, it took time and effort to build the wires one after another.
  (2) Moreover, in this prior art, the installation space of the wire winding apparatus separate from a wire saw was required in the factory. Furthermore, for example, when the wire is disconnected, the groove roller unit must be removed from the wire saw, or the wound unit must be attached to the wire saw, which is troublesome. Moreover, there is a possibility that the unit is fixed to the wire saw in a loose state. In this case, when the ingot is cut, the traveling direction of the wire row is inclined with respect to the axial direction of the ingot. As a result, there may be a problem in the quality of the wafer, for example, the crystal orientation of the cut wafer surface is different from the intended orientation.
[0005]
  Therefore, as a result of extensive research, the inventor automatically arranges the wire on almost the whole of the wire saw through the wire path in the guide channel if a tube-shaped guide channel is arranged almost all over the wire routing route. The present invention was completed by finding that it can be rolled up.
[0006]
OBJECT OF THE INVENTION
  An object of the present invention is to provide a wire saw capable of automatically winding a wire almost over the entire route of the wire. Another object of the present invention is to provide a wire saw that can automatically wind a wire smoothly around a guide pulley and a groove roller that are relatively difficult to wind. It is another object of the present invention to provide a wire saw capable of detecting clogging of a guide channel and the like. Still another object of the present invention is to provide a wire saw capable of smoothly performing an automatic winding operation at the time of winding a wire and a cutting operation at the time of cutting an ingot.
[0007]
[Means for Solving the Problems]
  In the first aspect of the present invention, after the wire fed from the feeding reel is wound in a coil shape between a plurality of groove rollers each having a wire groove formed on each outer peripheral surface through a plurality of guide pulleys, It has a structure that is wound around a take-up reel via a plurality of guide pulleys, and feeds the abrasive liquid containing loose abrasive grains while running the wire train wound between the groove rollers to cut the ingot. In a wire saw, a plurality of tube-shaped guide channels serving as a wire path when winding the wire are disposed almost over the entire wire routing path.In addition, a part of the guide channel coincides with a pulley outer cover provided on the inner surface with a pulley alignment groove that matches the pulley groove of the guide pulley and / or a wire groove formed on the peripheral surface of the groove roller. A roller outer cover with a roller alignment groove on the inner surfaceIt is a wire saw.
[0008]
  The wire saw to which the invention is applied may be of any kind. For example, the wire may be cut by pressing / contacting the ingot against the wire row, or by cutting the wire row against the ingot. The ingot may be in contact with the upper part of the wire row or may be pressed against the lower part of the wire row. The number of groove rollers may be a plurality of grooves such as two or three spaced apart from each other by a predetermined interval.
  Furthermore, with this wire saw, a method of performing or not performing the rotation of the wire, traveling in one direction or traveling back and forth may be used. As the wire fed from the feeding reel, for example, a generally used piano wire or twisted wire of about 0.16 to 0.20 mm can be used. The wire feeding speed at the time of winding is increased from 0.06 to 0.3 m / min at the initial movement, and is 1 to 10 m / min at the stable constant speed.
[0009]
  Examples of the material for the guide channel include various metals such as stainless steel, various hard synthetic resins such as ABS, and various kinds of wood. The inner diameter is changed according to the thickness of the wire. That is, the inner diameter of the guide channel is such that the wire traveling at high speed in the internal space does not interfere with the traveling of the wire by contacting the inner peripheral surface of the channel, and does not obstruct the installation of the adjacent guide channel or other peripheral parts. The inner diameter is about.
  Further, the guide channel connecting portion is preferably a structure that is tight at the time of winding work, but becomes loose at the time of cutting work and leaves room for the wire to travel with a margin. For this purpose, the end portion of each guide channel may be expanded outward in a trumpet shape, for example. With a trumpet shape, the wire is less likely to catch or deviate from the end of the guide channel.
[0010]
  The guide channel includes a straight channel and a curved channel. In addition, a plurality of normal guide channels are arranged at required portions of the wire routing route. It should be noted that the designer can arbitrarily determine the number of parts in which part of the routing route.
  The guide pulley may be a fixed pulley or a movable pulley. Moreover, the number of installation is not limited. The number of groove rollers may be a plurality of two or three. Examples of the ingot include those made of silicon single crystal, magnetic material, ceramics, and the like.
  Any abrasive liquid for cutting an ingot can be used as the abrasive liquid for cutting. For example, when a silicon single crystal ingot is cut, a known component including abrasive grains having an average particle diameter of 10 to 50 μm can be employed. The abrasive liquid supply device may have any structure.
  Furthermore, the guide channel for the wire row wound between the groove rollers is divided into a plurality of portions in the axial direction of the groove roller, and the wire row is also divided into a plurality of portions. If a take-up reel is provided, the length of the wire wound around each pay-out reel can be shortened compared to the case where there is a single pay-out reel, and the entire wire saw can be reduced, and the automatic winding time can be reduced. Shortened. For example, if the guide channel and the wire row are divided into five, this automatic winding time is reduced to 1/5.
  The material and shape of the pulley outer cover are not limited. In short, a pulley alignment groove that matches the pulley groove of the guide pulley may be provided on the inner surface of the cover.
The material and shape of the roller outer cover are not limited. In short, it is only necessary that a roller alignment groove that matches a plurality of wire grooves formed in parallel on the outer peripheral surface of the groove roller is provided on the inner surface of the cover.
[0011]
  The invention described in claim 2The wire saw according to claim 1, wherein at least a guide channel disposed at an ingot cutting portion between the groove rollers can be assembled and removed..
  The guide channel should just be arrange | positioned at the ingot cutting | disconnection part between groove rollers at least. For example, a guide channel provided in the entire wire saw may be assembled and removed. As the assembly / removal structure of the guide channel, for example, a channel mounting pin may be used, and the guide channel may be easily assembled or removed by this pin.
[0012]
  The invention according to claim 3The wire fed from the feeding reel is wound in a coil shape between a plurality of groove rollers each having a wire groove formed on each outer peripheral surface through a plurality of guide pulleys, and then passed through another plurality of guide pulleys. The structure is wound around a take-up reel and loose abrasive grains In the wire saw that runs the wire train wound between the groove rollers and cuts the ingot while supplying the abrasive liquid containing the wire, the wire path at the time of wire winding is provided in almost the entire area of the wire routing path. A wire saw in which a plurality of tube-shaped guide channels are arranged and at least a guide channel arranged at an ingot cutting portion between the groove rollers can be assembled and removed.
[0013]
  According to a fourth aspect of the present invention, the wire passage detecting means is provided in the middle of the wire routing route, and the feeding of the wire from the feeding reel is controlled by the presence or absence of a detection signal from the wire passage detecting means. The wire saw according to any one of claims 1 to 3, wherein a control means is provided.
  The wire passage detection means here means whether or not there is a conductive wire by means of a non-contact type position sensor using light such as laser light or infrared light, or a coil wound around the guide channel using an insulating material. An electromagnetic sensor or the like to detect can be employed.
  The installation position of the passage detection means may be any position on the wire routing path. For example, the clearance between the feeding reel and the first guide channel, the clearance between the guide channels, the clearance between the guide channel and the guide pulley, the clearance between the guide channel and the groove roller, the clearance between the last guide channel and the take-up reel, etc. Good.
  The control means here controls the feeding of the wire from the feeding reel based on the detection signal from the passage detecting means. That is, for example, the wire winding is controlled by a wire movement program, an alarm / stop function at the time of abnormality, a wire feeding speed adjustment program, and the like.
[0014]
[0015]
[Action]
  According to the first to fourth aspects of the present invention, the tube-shaped guide channel is disposed substantially over the entire wire routing route. As a result, the wire fed from the feeding reel is first automatically passed between the plurality of groove rollers having the wire grooves on the outer peripheral surface through the wire path in each guide channel between the guide pulleys on the feeding side of the wire saw. It is wound around. Of course, each feeding reel and each groove roller also constitute the above-mentioned routing path, and a wire path of the guide channel is also formed in this portion. In addition, when a wire is wound around the wire groove formed in the outer peripheral surface of each groove roller, it will become a coil-shaped wire row | line | column.
  Thereafter, the wire that has passed through the groove roller passes through a wire path in each guide channel between a plurality of guide pulleys on the winding side of the wire saw. Then, the wire reaches the take-up reel and is taken up. As a result, the wire is automatically wound up almost over the entire route.
[0016]
  When the wire fed from the feeding reel passes through the guide pulley, it passes through a wire path formed between the pulley groove of the guide pulley and the pulley alignment groove of the pulley outer cover, so that the wire is relatively wound. It is possible to automatically wind the wire smoothly even on the portion of the guide pulley where it is difficult.
Further, when the wire fed from the feeding reel passes through the groove roller, it passes through the wire path formed between the wire groove of the groove roller and the roller alignment groove of the outer roller cover, A wire can be automatically wound smoothly around a grooved roller portion that is difficult to wind.
[0017]
  Furthermore, the wire is wound up after assembling the guide channel to the cutting work portion of the ingot at least between the groove rollers. After the winding is completed, at least the guide channel of the cutting work part is removed, and then the ingot is cut by the wire train exposed to the cutting work part. Thereby, the automatic winding operation | work at the time of wire winding and the cutting operation | work at the time of an ingot cutting | disconnection can be implemented smoothly.
[0018]
  According to the fourth aspect of the present invention, the presence or absence of a wire detection signal from the passage detection means detects the presence or absence of a wire clogging in the wire path in the guide channel. Based on the detection result, the feeding of the wire from the feeding reel is controlled by the control means.
[0019]
[0020]
DETAILED DESCRIPTION OF THE INVENTION
  Embodiments of the present invention will be described below with reference to the drawings.
  FIG. 1 is a configuration diagram of a wire saw according to an embodiment of the present invention, FIG. 2 is an elevation view of the dancer roller portion, and FIG. 3 is an enlarged sectional view of a wire path portion of the guide roller. 4 is an enlarged perspective view of the groove roller, and FIG. 5 is an enlarged cross-sectional view of a wire path portion of the groove roller.
[0021]
  In FIG. 1, 10 is a wire saw, and this wire saw 10 is an apparatus for cutting a single crystal silicon ingot I pulled up by the CZ method into a large number of wafers, and a large number of wires 11a are horizontally aligned. The wire row 11 is bundled. The wire 11a is unwound from the unwinding reel 12, and is wound around the three groove rollers 14 arranged in a triangle through the dancer pulley portion 13 on the unwinding side. A plurality of parallel wire grooves 14 a are formed on the outer peripheral surface of each groove roller 14. After that, it is wound around the take-up reel 16 through the dancer pulley portion 15 on the take-up side. The wire train 11 of the groove roller 14 is reciprocated by causing the drive motors 17 and 18 to reciprocate the take-up and take-up reels 12 and 16 at the same speed clockwise in FIG. A pair of abrasive liquid supply portions 19 for continuously supplying the abrasive liquid onto the wire row 11 are disposed above both sides of the groove roller 14. The abrasive liquid is a mixture of high-viscosity SiC free abrasive grains having an average particle diameter of 40 μm.
  Both dancer pulley parts 13 and 15 have a pair of fixed-side guide pulleys 22 separated from each other by a predetermined distance, and a lifting pulley 24 that is a kind of guide pulley and on which a weight 23 is suspended (see FIG. 2).
[0022]
  The feature of the present invention is that, as shown in FIG. 1, the wire path at the time of winding the wire is provided almost in the entire routing path of the wire 11a from the supply reel 12 of the wire 11a through the groove roller 14 to the take-up reel 16. A plurality of tube-shaped guide channels 30 are provided. Hereinafter, the guide channel 30 will be described in detail.
  The guide channel 30 is made of aluminum (or glass or ceramic) with the wire contact portion being finish-polished. For example, the straight channel 31 disposed between the feeding reel 12 and the dancer pulley portion 13 on the feeding side, and other curves. There is a channel 32. The inner diameter of each channel 31, 32 is designed to a predetermined value. Further, the end of each guide channel 30 has a trumpet shape. Thereby, the wire 11a is not easily caught on the end of the guide channel 30 or deviated from the gap between the channels.
[0023]
  Among the straight channels 31, the straight channel group 311 covering the wire row 11 is a unit in which the straight channels 31 are integrally arranged in a number corresponding to the number of wires 11 a in the wire row 11. Moreover, the straight channel group 312 arrange | positioned among the straight channel group 311 in the ingot cutting | disconnection part (triangular base part) between the groove | channel rollers 14 is divided into two vertically so that assembly | attachment removal is possible. These upper and lower parts can be hooked and detached with a single touch by a channel mounting pin (not shown).
  The first linear channel 31 on the supply reel 12 side and the last linear channel 31 on the take-up reel 16 side reciprocate on the outer peripheral surface of the reel when the wire 11a from the reels 12 and 16 is supplied or taken up. Swing is performed according to the winding end position of the wire 11a. This swinging is performed with the end on the side of the corresponding dancer pulleys 13 and 15 as a fulcrum.
  Further, the curved channel 32 includes a pulley outer cover disposed on the outer peripheral side portion of each pulley 22, 24 and a roller outer cover disposed on the outer peripheral side portion of the groove roller 14. Among these, the roller outer cover is a curved channel group 321 in which the curved channels 32 are integrally arranged side by side in accordance with the number of wires 11a of the wire row 11. Each straight channel 31 or each curved channel 32 has a length and a curvature corresponding to each part.
[0024]
  In the middle of the routing route of the wire 11a in the wire saw 10, it is an example of a passage detection means of the wire 11a, and the reflected light of the laser light emitted from the light emitting portion is received by the light receiving portion, and the passage of the wire 11a is detected. A large number of optical sensors 33 to be detected are arranged. Specifically, the optical sensor 33 is arranged between the feeding reel 12 and the first straight channel 31, between the channels 31 and 32 in the middle of the path, between the straight channel group 311 and the curved channel group 321, and in a curved line. Between the channel group 321 and the straight channel group 312, between the curved channel group 321 and the straight channel 31, and between the last straight channel 31 and the take-up reel 16. Each optical sensor 33 is electrically connected to a control means 34 that controls the feeding of the wire 11a from the feeding reel 12 depending on the presence or absence of a detection signal.
[0025]
  Next, a wire winding operation in the wire saw 10 according to one embodiment of the present invention will be described.
  As shown in FIG. 1, for example, in a wire saw 10 using a wire 11 a having an outer diameter of 180 μm, the driving motor 17 is driven to increase from an initial movement of about 0.06 to 0.3 m / min and at a stable constant speed of 1 to 10 m The wire 11a fed out from the feeding reel 12 at a rate of / min first passes through the wire path of the straight channel 31 on the most feeding side and enters the inside of each curved channel 32 of the dancer pulley section 13. Thereafter, the wire 11a sequentially passes through the straight channel 31, the straight channel group 311, the straight channel group 312 that can be assembled and removed, and the curved channel group 321 in this order. Then, it is wound around these groove rollers 14 in a coil shape. Subsequently, the wire 11 a that has passed through each groove roller 14 passes through a straight channel 31 and a wire path in each curved channel 32 of the dancer pulley portion 15 on the winding side of the wire saw 10. Thereafter, the wire 11a reaches the take-up reel 16 via the linear channel 31 arranged on the most winding side, and is automatically clipped (fixed) by a clip device (not shown). Alternatively, when the sensor reaches the take-up reel 16, the wire travel may be stopped and clipped manually. By following such a path, the wire 11a is automatically wound up over the entire route of the wire saw 10.
[0026]
  For example, when the wire 11a deviates from a predetermined wire path due to a design error, a manufacturing error, an assembly error, a maintenance error, etc. The optical sensor 33 arranged in the main part detects an abnormality in conjunction with the control means 34, issues an alarm by an alarm, and performs necessary measures such as an emergency stop.
[0027]
  Next, an operation of cutting the ingot I with the wire saw 10 will be described with reference to FIGS. 1 and 4. While supplying the abrasive liquid from the abrasive liquid supply unit 19, the wire row 11 is formed between the three groove rollers 14. To reciprocate. When the wire row 11 is reciprocating, the ingot I is pressed against the wire row 11 from below, so that the ingot I sequentially has a cutting start end portion with a short contact length, a cutting center portion with a long contact length, and a contact length. Gradually cut into short cut ends. That is, during the reciprocating travel of the wire row 11, the abrasive grains in the abrasive liquid are rubbed against the bottom of the cutting groove by each wire 11a of the wire row 11 and gradually scraped, and finally cut into a large number of wafers. The Prior to this cutting operation, the straight channel group 312 at the ingot cutting portion between the groove rollers 14 is removed. Thereby, the automatic winding operation | work at the time of winding of the wire 11a and the cutting operation | work at the time of the cutting | disconnection of the ingot I can be implemented smoothly.
[0028]
  In the wire saw 10 according to this embodiment, the wire 11a has the following additional effect in addition to the basic effect that the wire 11a is automatically wound around the entire area of the wire saw 10.
  That is, the above-described conventional wire winding apparatus requires a space for installing the wire winding apparatus in the factory separately from the wire saw. However, since the wire 11a is wound up only inside the wire saw 10 here, this installation space becomes unnecessary. Moreover, in this conventional wire winding apparatus, it is necessary to attach and detach the groove roller unit from the wire saw every time the wire is wound up, but this labor is also unnecessary. Further, when the unit is mounted, there is a possibility that the groove roller unit is mounted on the rotating main shaft of the wire saw with a backlash. As a result, the quality of the wafer may be degraded. However, this embodiment can solve this problem.
[0029]
  As shown in FIG. 3, when the wire 11a passes through each guide pulley, the wire 11a is connected to the pulley grooves 22a and 24a of the pulleys 22 and 24 and the pulley alignment groove 32a of the curved channel 32 (pulley outer cover). Since it passes through the wire path formed between them, the wire 11a can be automatically wound smoothly around the pulleys 22 and 24, which are difficult to wind as compared with the straight portion.
[0030]
  Further, as shown in FIG. 5, when the wire 11a passes through the groove roller 14, the wire path formed between the wire groove 14a of the groove roller 14 and the roller alignment groove 321a of the curved channel group 321 (roller outer cover). Therefore, the wire 11a can be automatically wound smoothly around the groove roller 14 which is relatively difficult to wind.
[0031]
  Furthermore, the presence or absence of a wire detection signal from the optical sensor 33 detects the presence or absence of clogging or deviation of the wire 11a in the wire path in the guide channel 30, and based on this, the control means 34 uses the wire from the supply reel 12 11a is controlled. Thereby, it is possible to deal with wire clogging during the automatic winding of the wire 11a.
  The present invention is not limited to this embodiment, and design changes and the like within a range not departing from the gist are included in the present invention.
[0032]
【The invention's effect】
  According to this invention, since the tube-shaped guide channel is disposed in almost the entire area of the wire routing path, the wire fed from the feeding reel is wound around the wire groove of each groove roller in the middle of routing. It is automatically sent to the take-up reel through a wire path in the guide channel. As a result, the wire can be automatically wound up almost all over the wire saw routing route.
  In the prior art, an installation space for the wire winding device separate from the wire saw is required in the factory, but this is not necessary. Moreover, it is not necessary to attach and detach the groove roller unit from the wire saw every time the wire is wound up. Further, it is possible to prevent the quality of the wafer from being deteriorated due to loose mounting when the unit is mounted.
[0033]
  The part of the guide pulley that is relatively difficult to wind because it is configured to pass through the wire path formed between the pulley groove of the guide pulley and the pulley alignment groove of the pulley outer cover when the wire passes through the guide pulley. In addition, the wire can be automatically wound smoothly.
Also, since the wire path formed between the wire groove of the groove roller and the roller alignment groove of the roller outer cover is passed when the wire passes through the groove roller, the groove roller is relatively difficult to wind. The wire can be smoothly and automatically wound around this part.
[0034]
Furthermore, since at least the guide channel disposed at the ingot cutting portion between the groove rollers can be assembled and removed, the automatic winding operation when winding the wire and the cutting operation when cutting the ingot can be smoothly performed. Can do.
[0035]
  According to the fourth aspect of the present invention, the presence or absence of a wire clogging in the guide channel is detected based on the presence or absence of a wire detection signal from the passage detection means, and based on this, the control means detects the supply reel. Since the feeding of the wire from the wire is controlled, it is possible to cope with the wire clogging during the automatic winding of the wire.
[0036]
[Brief description of the drawings]
FIG. 1 is a configuration diagram of a wire saw according to an embodiment of the present invention.
FIG. 2 is an elevation view of a dancer roller portion according to one embodiment of the present invention.
FIG. 3 is an enlarged cross-sectional view of a wire path portion of a guide roller according to an embodiment of the present invention.
FIG. 4 is an enlarged perspective view of a groove roller according to an embodiment of the present invention.
FIG. 5 is an enlarged cross-sectional view of a wire path portion of a groove roller according to an embodiment of the present invention.
[Explanation of symbols]
  10 Wire saw,
  11a wire,
  11 Wire row,
  12 Reel reel,
  14 groove roller,
  14a wire groove,
  16 take-up reel,
  22 guide pulley,
  22a, 24a pulley groove,
  24 lifting pulley,
  30 guide channels,
  31 straight channel,
  311 straight channel group,
  312 linear channel group,
  32 curved channel (pulley outer cover),
  32a Pulley alignment groove,
  321 Curved channel group (roller outer cover),
  321a Roller alignment groove,
  33 optical sensor (passage detection means),
  34 control means,
  I Ingot.

Claims (4)

The wire fed from the feeding reel is wound in a coil shape between a plurality of groove rollers each having a wire groove formed on each outer peripheral surface through a plurality of guide pulleys, and then passed through another plurality of guide pulleys. And has a structure wound on a take-up reel,
In a wire saw that cuts an ingot by running a wire train wound between the groove rollers while supplying an abrasive liquid containing free abrasive grains,
A plurality of tube-shaped guide channels that serve as wire paths when winding the wire are disposed in almost the entire area of the wire routing path , and
A pulley outer cover in which a part of the guide channel is provided with a pulley alignment groove on the inner surface that matches the pulley groove of the guide pulley and / or a roller alignment groove that matches a wire groove formed on the peripheral surface of the groove roller A wire saw that is a roller outer cover provided on the inner surface . The wire saw according to claim 1, wherein at least a guide channel disposed at an ingot cutting portion between the groove rollers can be assembled and removed . The wire fed from the reel is passed through a plurality of guide pulleys, wound around a plurality of groove rollers each having a wire groove formed on each outer peripheral surface, and then passed through another plurality of guide pulleys. And wound around a take-up reel,
  In a wire saw that cuts an ingot by running a wire train wound between the groove rollers while supplying an abrasive liquid containing free abrasive grains,
  A plurality of tube-shaped guide channels serving as wire paths at the time of wire winding are disposed over almost the entire area of the wire routing path, and at least guide channels disposed in the ingot cutting portion between the groove rollers, Wire saw that can be assembled and removed freely.   The wire passage detecting means is provided in the middle of the wire routing route, and control means for controlling the feeding of the wire from the feeding reel according to the presence or absence of a detection signal from the wire passage detecting means is provided. The wire saw according to any one of claims 1 to 3.

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