JPH1119861A - Wire saw, and work cutting method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To supply a sufficient quantity of grinding grains in the grinding liquid to a work cutting part by rotating a delivery reel and a winding reel in the same direction around an axis of a wire. SOLUTION: A rotary disc 17 is rotated by a rotary motor 18 of each reel 16. The reel 16 is concentrically rotated with the axis of the wire in the wire delivering or wire winding direction. At each wire line dividing parts 11A-11D, the wire, which is delivered or wound from/around the predetermined delivery or winding bobbin 20 in the same circumferential direction, is rotated in the same circumferential direction. With this structure, in spite of the high-speed traveling of the wire, at the time of cutting an ingot 1, cutting is always performed in the condition that the grinding grains (x) of the grinding liquid is adhered to the whole of the circumferential surface of the wire.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wire saw for cutting a hard material such as a semiconductor material, a magnetic material, and a quartz crystal on a wire (wire row) such as a drawn steel wire while applying abrasive grains thereto, and uses the wire saw. Work cutting method. Specifically, between the wire for cutting the work (wire row) and the cut portion of the work cutting groove, a sufficient amount of abrasive liquid can always be supplied during traveling,
The present invention relates to a wire saw and a work cutting method which prevent cutting and clogging of abrasive grains at the time of cutting a work and eliminate various problems caused by the cutting and clogging of abrasive grains.

[0002]

2. Description of the Related Art A wire saw is an apparatus for cutting a work such as a silicon single crystal ingot into a plurality of portions by a traveling wire. In other words, while continuously supplying a grinding liquid in which free abrasive grains are mixed with a dispersant to a work, a wire (wire row) traveling unidirectionally or reciprocatingly is pressed relatively to the work, and a work generated there is formed. The work is cut into a plurality of workpieces (for example, wafers) by a grinding action between loose abrasive grains or fixed abrasive grains. Pure water, cutting oil, and the like are known as dispersants for the abrasive liquid, and alumina, SiC, and the like are known as free abrasive grains (hereinafter sometimes simply referred to as abrasive grains). Hereinafter, the cutting state of the work by the wire saw will be specifically described with reference to FIGS. FIG. 4 is a cross-sectional view of a work (silicon ingot) using a wire saw according to a conventional means, taken along a plane including a work axis in a cutting operation state. FIG. 5 is a cross-sectional view of the work taken along a plane perpendicular to the work axis in a cutting operation state of the work. FIG.
(A) is an enlarged sectional view in a plane perpendicular to the wire axis near point a in FIG. 5. FIG. 6B is an enlarged cross-sectional view near a point b in FIG. 5 taken along a plane perpendicular to the wire axis.

As shown in FIG. 4, when cutting a work I which is a cylindrical ingot by a conventional wire saw,
While supplying the abrasive fluid containing the abrasive grains from above the work I, each wire of the wire row 100 reciprocatingly traveling is relatively pressed against the cut portion on the back side of the cutting groove of the work I, thereby cutting the work I. I do. This is because the abrasive grains in the supplied abrasive liquid are violently rubbed against the cut portion while a part of the abrasive grains are rolling by the running motion of the wire array 100 and the pressing force, so that the workpiece I is continuously reduced little by little. Due to the progress of crushing and cutting by cutting.

When the work I is cut in this manner, since the work I has a cylindrical shape, as shown in FIG.
The cutting portion distance d changes according to the cutting progress of the work I. The position of the maximum value is the diameter portion of the work I. The maximum value of the cut distance d is 150 to 300 m in the case of a recently increasing silicon single crystal ingot.
m. However, as the cutting distance d increases, the cutting efficiency of the work I is greatly reduced.

[0005] The reasons are as follows. That is, (1) in the latter half portion of the cutting portion of the work I, the abrasive pressing force of the wire gradually reduces the abrasive grains between the cutting portion on the back side of the cutting groove of the work I and the traveling wire. (See FIGS. 6A and 6B). (2) The abrasive grains are extruded from the cutting portion by an amount corresponding to the amount of chips, which are cutting chips discharged from the cutting portion of the work I into the polishing liquid during cutting, gradually accumulating in the polishing liquid. Due to these phenomena (1) and (2), the total number of abrasive grains between the cut portion and the wire that effectively works for cutting is reduced (hereinafter, referred to as “grain”).
This is called abrasive grain breakage).

[0006] This abrasive grain breakage phenomenon is a factor that causes various adverse effects in the conventional wire saw process. That is, as a direct influence of the cutting of the abrasive grains on the cutting efficiency, suppression of the cutting speed can be mentioned. For example, in the one-way traveling mode in which the entire length of the wire is traveled only once in one direction to cut the work I, the vicinity of the cutting point b of the cutting portion distance d lacks abrasive grains compared to the vicinity of the cutting point a. ing. As a result, the cutting speed of this portion is reduced, and wire breakage is likely to occur. Therefore, in order to avoid this, in the case of a large-diameter work, the traveling speed of the wire during actual operation is usually reduced by 30 to 50% or more as compared with the case of a small-diameter work. Also,
In the reciprocating traveling mode in which the work is cut by reciprocating the wire as shown in FIG. 5, idling is performed every time the traveling direction of the wire is switched. That is, the repetition of the change of the cutting speed at the corresponding cycle instead of the insertion of the cutting point a and the cutting point b occurs at both ends of the cutting distance d. Is achieved. As a result, when other cutting conditions are the same, the cutting speed as a whole is usually set to a value that is lower by 15 to 25% or more than the cuttable speed near the cutting point a.

[0007] In addition, for example, the dimensional accuracy of a workpiece after cutting is affected by the breakage of abrasive grains. That is, since the cutting efficiency is good at the cutting point a in the one-way traveling mode, the cutting margin is large and the cutting margin is small at the cutting point b. Accordingly, in the case of cutting with a wire row running in parallel, the thickness distribution of the obtained work, for example, a wafer or a thin plate is thin on the point a side and b
The point side has a thick tapered shape. Moreover, this thickness unevenness,
It becomes larger as it exceeds 10 to 20 μm. In fields such as semiconductor materials that require high-precision dimensions, it is necessary to remove this thickness unevenness by machining such as wrapping and grinding in the post-process, which reduces the yield in raw material crystals and processing and reduces processing costs. It is increasing.

In the industrial field such as semiconductors where the diameter of the work I tends to be large, several proposals have been made to cover such weak points of the conventional wire saw.
For example, in order to cover a large decrease in the cutting speed, the traveling speed of the wire is increased from about 100 to 300 m / min for a small-diameter work to about 400 to 1000 m / min, and the cutting speed is made close to that of a small-diameter product. At the same time, measures are taken to reduce the amount of wear per unit length of the wire (per the same cutting load) to prevent a reduction in work efficiency due to the wire replacement work. However, in this method, the amount of wire wound around the payout reel increases (for example, 18
0 μm steel wire is 300-500 m long and weighs 60-100 kg). As a result, the size of the wire saw using the wire saw is increased, and the equipment cost is increased.

Conventionally, as a wire saw for rotating each wire in a wire row around an axis, for example, the Japanese Utility Model Application
No. 9-14136 and Japanese Patent Application Laid-Open No. 9-70747.
The one described in Japanese Patent Application Laid-Open Publication No. H10-260, 1993 is known. The former conventional means uses a rotating force generated by the relative reciprocating movement of these rollers while holding the running wire array at a position deviated from the cut portion by two rollers, and thereby each wire of the wire array is rotated. This is a device that rotates reciprocally around the axis. In the latter conventional means, a moving table that presses a work against a wire row is installed on a side where a rotating shaft of a groove roller is located, so that the wire is wound in a state of being shifted by one pitch between the groove rollers. Under the structure of the wire saw, the device utilizes the fact that the wire naturally twists a little bit each time the wire changes over the wire groove of each groove roller. Thereby, uneven wear of the wire and undulation of the workpiece cut surface can be reduced.

[0010]

However, in the former conventional means, when the wire array is run at a high speed, the rotation of the wire while being sandwiched between the rollers slips on the peripheral surface of the rollers. As a result, undulation in the cutting direction of the workpiece cut surface caused by uneven wear of the wire causes a problem again. On the other hand, the latter conventional means has a problem that, for example, when the used wire is a new wire, the intended effect cannot be sufficiently obtained unless the wire is used two to four times. This is supported by the example data in the accompanying specification. In other words, according to the data, not only are the functions and effects insufficient, but also the problems (cutting efficiency, cutting accuracy, yield reduction) due to the cutting of the abrasive grains of the large-diameter workpiece, and high-speed wire running The associated problem (weighting of the wire reel and the device) cannot be solved.

[0011]

SUMMARY OF THE INVENTION An object of the present invention is to supply a sufficient amount of abrasive liquid at all times during travel between a wire (wire array) for cutting a work and a cut portion of a work cutting groove. , Prevents the cutting of abrasive grains when cutting the work, thereby stabilizing the cutting efficiency to a high degree, securing a high cutting speed and a high-precision cutting surface, and reducing the uneven thickness of the work after cutting,
It is an object of the present invention to improve the yield of workpieces from raw materials, simplify post-processes, reduce the amount of wire wear and uneven wear, and extend the life of wires by reducing wire breakage. It is a further object of the present invention to provide a wire saw capable of reliably and stably rotating and controlling a wire (wire row) around an axis with a relatively simple and inexpensive structure. Furthermore, the present invention
Provided is a wire saw that can reduce the size of a wire saw, reduce equipment cost, and further reduce the obstacle to rotation around the wire axis, and can more reliably rotate the entire wire row around the axis. , Its purpose.

[0012]

According to a first aspect of the present invention, a workpiece is cut by pressing a wire fed from a pay-out reel against a workpiece, which is a workpiece to which a polishing liquid is supplied, A wire saw in which a wire after cutting is wound up on a take-up reel, the wire saw provided with rotating means for rotating the pay-out reel and the take-up reel around the axis of the wire in the same rotational direction.

The wire saw to which the present invention is applied may be of any type. For example, the workpiece may be cut by contacting the wire while pressing it, or may be cut by pressing the wire against the workpiece. Further, the wire may travel in a horizontal direction, a vertical direction, or any other direction, and the workpiece may come into pressure contact from either side of the wire travel surface. The number of groove rollers
It suffices if two or more wires are separated from each other at a predetermined interval. The traveling of the wire may be one-way traveling or reciprocating traveling. Free abrasive grains are used as the abrasive liquid for cutting, but in the case of a fixed abrasive method in which abrasive grains are fixed to a wire, only water containing no free abrasive grains may be used. Even when loose abrasives are used, there are a variety of applicable abrasives and abrasive fluids as described above. The polishing liquid supply device may have any structure and function. Further, the mechanisms installed on the traveling path of the wire may be of any type as long as they do not hinder the rotation of the wire about the axis. In addition, the means for rotating the two reels may be an electric motor, a pneumatic type, a hydraulic type, other types of rotary power, or a type with a rotation transmitting mechanism.

In any case, what is important is that the wire from the above-mentioned feeding point to the winding point via the cutting section rotates at substantially the same speed over the entire length and in the same direction around the axis, and the wire breaks due to twisting or the like. In this case, both reels are simultaneously rotated at the same speed in the same direction so that stable running without the problem described above can be performed. The rotation of one of the reels, the non-synchronization of the rotation of the two reels, the difference in rotation speed, etc. will give an excessive force in the twisting direction to the wire and cause disconnection and abnormal operation. No. However, rotating one reel relative to the other within the elastic deformation region of the wire is included in the scope of the present invention.

According to a second aspect of the present invention, a plurality of wires are disposed in parallel between the groove rollers by passing the wire fed from the reel on and between the plurality of groove rollers separated from each other. The wire row
While the abrasive fluid containing loose abrasive grains is being supplied, the work as a workpiece is cut into a plurality of sheets at the same time by the wire row, and the wire row is wound on a take-up reel by winding the wire after the cut. The wire reel is divided into a plurality of wire row division sections each having a plurality of wires, and the payout reel and the take-up reel are arranged for each wire row division section. This is a wire saw provided with a rotating means for rotating the wire around the axis of the wire in the same direction. The number of the wire row dividing sections into which the wire rows are divided may be two, three, four, five or more, up to the maximum number of wire rows. At this time, the wire row may be divided at a fixed pitch or may be divided into predetermined lengths different from each other. For example, the length of the work may be divided into ten equal parts in the axial direction of the groove roller, or the whole work may be separated by one.
The pitch may be one groove pitch equally divided into the length of each sheet.

According to a third aspect of the present invention, a wire fed from a wire-saw feeding reel is caused to travel, and a workpiece, which is a workpiece to which the abrasive fluid is supplied, is cut by the wire. In the method of cutting a work to be wound up on a take-up reel, the work reel is rotated around the axis of the wire by rotating the pay-out reel and the take-up reel around the axis of the wire, respectively. It is.

According to a fourth aspect of the present invention, the work is a cylindrical ingot, and when the work is cut, a wire having a traveling speed of 300 to 1000 m / min is required to travel along a diameter portion of the work. 4. The method according to claim 3, wherein the wire is rotated around the axis at an angle of 90 ° or more. During the time required for the wire during cutting travel to travel the cutting portion distance from the cutting point to the cutting point of the work, 0.25 to 10 rotations around the axis of the wire,
Preferably, it rotates in one direction at a speed of 0.5 to 3 rotations.
Alternatively, the wire reciprocates at a rotation amount of not less than 0.25 rotation, preferably not less than 0.5 rotation per half cycle, and not more than the rotation amount corresponding to the twisting strength of the wire used.

[0018]

According to the first to fourth aspects of the present invention,
The work is relatively pressed against the traveling wire while supplying the abrasive fluid that may include loose abrasive grains, and the work is cut by the grinding action of the loose abrasive grains or the fixed abrasive grains. At this time, the running wire is forcibly rotated by rotating the pay-out reel and the take-up reel at both ends thereof around the wire axis at the pay-out point and the take-up point, respectively. In addition, the middle course of the traveling is constituted by guide rollers, groove rollers, and a cutting portion of the work covered with an abrasive liquid having lubricating ability, which hardly gives a resistance to this rotational movement. Therefore, the rotation of the wire around the axis, which is a feature of the present invention, can be reliably performed.

However, in the case of the wire feeding side, the position at which the wire is rotated may be any position between the wire feeding point of the feeding reel and the wire groove entry point of the groove roller, while the wire winding side may be provided at the wire winding side. In this case, the position may be any position between the wire winding point of the winding reel and the wire groove exit point of the groove roller. However, in this case, it is necessary to rotate all of the pay-out reel and the take-up reel and the wire guiding and operation control mechanisms disposed between the respective wire axes at these two points. Naturally, this method is also included in the applicable range of the present invention. According to the first aspect of the present invention, it is possible to rotate the wire around the axis relatively simply, inexpensively and reliably. According to the invention of each claim, the traveling wire can be surely rotated around its axis, so that the effect is not lost even under high-speed wire traveling conditions or when the number of times of wire use is small. .
As a result, the amount of wear of the wire becomes uniform around the axis, and there is no disconnection due to uneven wear. Therefore, the life of the wire can be extended, and the running cost of the wire saw can be reduced.

In particular, according to the second aspect of the present invention, the respective rotation mechanisms of the pay-out reel and the take-up reel are provided for each of the wire row dividing sections obtained by dividing the wire row. Since the amount is reduced, both reels and the rotating mechanism can be made smaller. Therefore, the size of the wire saw can be significantly reduced, and the equipment cost can be reduced. In addition, the resistance when rotating the wire around the axis is reduced by dividing the wire row,
It is easy to reliably and stably rotate the wire.

According to the fourth aspect of the present invention, when the wire is run at a high speed of 300 to 1000 m / min, the time during which the wire travels in the cut portion from when the wire is cut into the work to when the wire is cut out is reduced. 9 to 60 even for large-diameter workpieces (for example, ingots with a diameter of 150 to 300 mm)
Milliseconds and short. However, during this time, the abrasive liquid is pushed out of the cutting portion by the pressing force of the wire against the cutting portion, and the dilution of the abrasive concentration due to the accumulation of the work chips (cut powder) discharged at the time of cutting at the cutting portion. Progress. By the way, in the direction around the axis of the wire, the portion opposite to the side facing the cut portion of the work is in contact with fresh abrasive fluid supplied to the cut groove of the work. Therefore, the wire is rotated about 1/4 turn or more (for example, 1/4 to 3/4 turn) around the axis to supplement the abrasive grains or the abrasive liquid, so that a sufficient amount of the wire for cutting always remains on the peripheral surface of the cut portion of the wire. Abrasive grains can be secured. If the rotation is less than 1/4 rotation, a sufficient amount of abrasive grains cannot be secured. Further, even if the rotation speed is increased unnecessarily, the grinding liquid that has not been sufficiently replaced with fresh grinding liquid only returns to the gap between the wire and the cutting portion of the work, and the cutting efficiency does not increase. In addition, a high-speed rotating machine, which is disadvantageous for downsizing, is used as a rotating means of the pay-out reel and the take-up reel. As a result, it was confirmed that the abrasive cutting phenomenon that occurred in the conventional method did not occur. Also, the cutting speed is 0.8-1.
0 mm / min or more, and at the same time, a one-way traveling type with a work surface taper of 3 to 5 μm and a reciprocating traveling type with a surface flatness of less than 3 μm can be realized under large-diameter work and high-speed traveling conditions. I knew I could do it.

[0022]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view of a wire saw according to an embodiment of the present invention, FIG. 2 is an explanatory view of the ingot during cutting, and FIG. 3 (a) is an enlarged sectional view of a portion of FIG. FIG. 3B is an enlarged sectional view of a portion b in FIG. In FIG. 1, reference numeral 10 denotes a wire saw. The wire saw 10 is made of an ingot I having a diameter of 200 mm and made of single crystal silicon pulled up by the CZ method and having a maximum of 500 mm.
This is an apparatus for cutting wires into a large number of wafers having a thickness of, for example, 900 μm, and has a wire row 11 in which many wires are bundled in a horizontal row. The wire array 11 is reciprocated or travels in one direction by a drive motor between three groove rollers 12 arranged in an inverted triangle. Above both sides of the groove roller 12, a pair of abrasive fluid supply units 13 for continuously supplying the abrasive fluid onto the wire row 11 are provided. The polishing liquid has a high viscosity and is mixed with abrasive grains made of SiC having an average particle diameter of 25 μm.

The ingot I is mounted on a lift 15 via a carbon bed 14. Also, the wire row 11
Is divided into four wire row divisions 11A to 11D, and the reels 16A to 16D are connected to the wire start end and the wire end of each wire row division 11A to 11D.
Each of the reels 16 has a rotating disk 17, and at the center of the outer surface of the rotating disk 17, a rotating means as an example of rotating means for rotating the wires of the wire array 11 about the axis by 25000 min −1. The rotating shaft of the motor 18 is connected. A mounting piece 19 is provided upright on the outer peripheral portion of the inner surface of the rotating disk 17, and the wire of each of the wire row division parts 11 </ b> A to 11 </ b> D is wound on the leading end of the mounting piece 19.
A traveling motor 21 that feeds out and winds up at a maximum speed of 1000 m / min from 0 is mounted.

When the rotating disk 17 is rotated by the rotating motor 18 of each reel 16, the reel 16 is rotated around the same axis as the axis of the wire feeding or winding direction, whereby each of the wire row dividing parts 11A to 11A is rotated. In 11D, the wire fed or wound from the predetermined feeding or winding bobbin 20 rotates in the same circumferential direction. In addition, the feeding or winding bobbin is rotated by the traveling motor 21 to feed or wind the wire. In FIG. 1, reference numeral 22 denotes a guide pulley. Figure 2
In FIG. 3, reference numeral 11a denotes a wire of the wire array 11.
Ia is a groove cut by the wire 11a of the ingot I, and x is abrasive grains contained in the abrasive liquid.

Next, a method of cutting a workpiece using a wire saw according to an embodiment using the wire saw 10 will be described. As shown in FIG. 1, the wire saw 10 reciprocates the wire array 11 between the three groove rollers 12 while supplying the abrasive liquid from the abrasive liquid supply unit 13. When the ingot I is pressed against the wire row 11 from below during the reciprocating travel of the wire row 11, as shown in FIG.
In sequence, the cutting is gradually cut into a cutting start portion having a short contact length, a cutting central portion having a long contact length, and a cutting end portion having a short contact length. That is, at the time of reciprocation of the wire array 11, the abrasive grains x in the abrasive fluid are rolled by the wires 11a of the wire array 11 while being pressed against the bottom of the cutting groove Ia, that is, the cutting portion, or move while cutting. The work surface is gradually scraped off, and the work is finally cut into many wafers.

At this time, as shown in FIG.
1, the wire 11a of the wire row 11 is, for example, 80
While traveling at a high speed of 0 m / min (corresponding to a cutting portion traveling time of 15 milliseconds at the workpiece diameter portion), the rotating motor 18 rotates the wire 11a around its axis by 2000 min-1. Thereby, despite cutting the wire 11a at a high speed, when the ingot I is cut,
The wire 11a is cut with the abrasive grains x of the abrasive liquid attached to the entire peripheral surface. In addition, in both the forward and reverse running directions of the wire, the first half of the cutting groove Ia of the ingot 11 can be cut well as before (see also FIGS. 2 and 3 (a)). Even in the latter half of the cutting groove Ia where the liquid was severely drained, the abrasive grains x of the normal concentration were used.
A sufficient amount of the abrasive fluid containing is fed to cut the entire cutting portion including this portion satisfactorily (FIGS. 2 and 3).
(See also (b)). As a result, damage such as abnormal wear (uneven wear) and disconnection of the wire Ia is not relatively caused. In addition, the wire life is extended by 50 to 70% due to uniform wear. Therefore, running costs can be reduced. In addition, a high cutting speed (0.8 to 1.0 mm /
Min), and the ingot I can be cut.

Furthermore, the thickness unevenness of the wafer immediately after cutting is reduced, the yield of the wafer per ingot I is increased, and the warpage of the wafer immediately after cutting is also reduced. The cracking of the wafer was also reduced. At the time of cutting the ingot I, the entire reel 16 is rotated in the same direction around the axis coinciding with the axis of the wire 11a in the feeding direction and the winding direction by using the rotary motor 18 to rotate the wire 11a in the circumferential direction. Therefore, using a relatively simple and inexpensive structure, the wire 11
a can be rotated in the circumferential direction.

In this embodiment, the wire row is divided into four parts, and the wire of each divided part (at the start) has a diameter of 180 μm.
m and a length of 100 km. The wire traveling speed is up to 800 (m / min), and the average is 7
15 (m / min), and the cutting time is 235
The average cutting speed was 0.86 mm / min, and the total feeding distance of each wire was about 166 km (the running direction was changed once in the middle). The present invention is not limited to this embodiment, and includes any change in design without departing from the scope of the present invention.

[0029]

According to the wire saw and the work cutting method of the present invention, by rotating the pay-out reel and the take-up reel around the axis of the wire in the same rotation direction, the abrasive grains in the polishing liquid can always be sufficiently supplied. An appropriate amount can be supplied to the cutting portion of the work. As a result, the phenomenon of abrasive grain breakage at the work cutting portion is eliminated, and cutting efficiency can be stabilized at a high level. In addition, a high cutting speed and a high-precision cutting surface are secured to reduce the unevenness of the thickness of the work after cutting, thereby improving the work yield from raw materials, simplifying the post-process, reducing the amount of wire wear and uneven wear. Reduction can be achieved. Further, a longer life can be realized by reducing the disconnection of the wire.

In particular, in the wire saw according to the second aspect, the wire row is divided into a plurality of wire row dividing sections, and both reels are provided for each wire row dividing section. Since the rotating direction is made uniform and the wire is rotated around the axis of the wire by the rotating means, it is possible to reduce the size of the multi-wire saw having the above-described effects.
As a result, the equipment cost can be reduced, and the resistance when rotating the wire around the axis can be reduced. As a result, it is possible to reliably and stably rotate the wire around the axis in the multi-wire saw having the wire row.

In the method for cutting a workpiece using a wire saw according to a fourth aspect, when cutting the workpiece,
While the traveling speed of the wire is 300 to 1000 m / min, the wire is rotated at least 1/4 around the axis while traveling through the diameter portion of the ingot-shaped work. Even in the case of cutting a workpiece having a long target cutting width, a sufficient amount of abrasive grains in the abrasive fluid can always be supplied to the cutting section of the workpiece.
Thereby, each of the effects described above can be obtained.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a schematic configuration of a wire saw according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view illustrating a state in which an ingot is being cut by the wire saw according to one embodiment of the present invention.

FIG. 3A is a cross-sectional view taken along a line perpendicular to a wire, showing a portion a of FIG. 2 in an enlarged manner. FIG. 3B is an enlarged cross-sectional view of a portion b in FIG. 2 taken along a plane perpendicular to the wire.

FIG. 4 is a cross-sectional view taken along a plane including a work axis for explaining a work cutting state of a work using a conventional wire saw.

FIG. 5 is a cross-sectional view taken along a plane orthogonal to a workpiece axis for explaining a state of a workpiece cutting operation using a conventional wire saw.

FIG. 6A is an enlarged cross-sectional view near a point a in FIG. 5 taken along a plane perpendicular to the wire axis. FIG. 6B is an enlarged cross-sectional view in a plane perpendicular to the wire axis near point b in FIG. 5.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 wire saw, 11 wire rows, 11A-11D wire row division parts, 12 groove rollers, 16 reels, 18 rotation motors (rotation means), I ingot, x abrasive grains (free abrasive grains).

Claims (4)

[Claims] 1. A work, to which a grinding liquid is supplied, is pressed against a wire fed from a pay-out reel to cut the work, and the cut wire is wound up on a take-up reel. A wire saw, comprising: a rotating means for rotating the pay-out reel and the take-up reel around the axis of the wire while aligning their rotation directions. 2. A wire fed from a pay-out reel,
By bridging between a plurality of groove rollers spaced apart from each other, a wire row in which a plurality of wires are arranged in parallel between these groove rollers is formed, and while the abrasive fluid containing loose abrasive grains is supplied. In this wire saw, a workpiece as a workpiece is cut into a plurality of pieces at the same time, and the cut wire is wound on a take-up reel. The wire saw includes a plurality of wires each having a plurality of wires. The feed reel and the take-up reel are divided into a row dividing section, and the pay-out reel and the take-up reel are arranged in each of the wire row dividing sections. A wire saw provided with rotating means. 3. A workpiece cutting machine in which a wire fed from a reel of a wire saw is caused to travel, the wire is used to cut a workpiece which is a workpiece to which the abrasive liquid is supplied, and then the wire is wound up on a take-up reel. A method for cutting a workpiece, wherein the feeding reel and the take-up reel are rotated around the axis of the wire in the same rotation direction, whereby the traveling wire is rotated around the axis. 4. The method according to claim 1, wherein the work is a cylindrical ingot, and the cutting speed is 300 to 1000 m /
The workpiece cutting method according to claim 3, wherein the wire is rotated around the axis at an angle of 90 ° or more per time required for the minute wire to travel through the diameter portion of the workpiece.