JPH10202499A - Wire saw - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wire saw capable of stably oscillating and cutting a workpiece with a simple mechanism. SOLUTION: An ingot 30 is mounted on an oscillation mechanism 32 fitted to a work feed table 28, and the ingot 30 is caused to oscillate along the wire travel direction of a wire row 20, with the axial center of the ingot 30 taken as an oscillation center, on the operation of the oscillation mechanism 32. According to this construction, the ingot 30 always comes in contact with the wire row 20 even at the beginning of a cutting process, thereby preventing the appearance of a cut or the like. Also, a cutting process can be controlled very easily even in the case of cutting the ingot 30 through the change of an oscillation angle, depending on the feed amount thereof.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a wire saw.
In particular, the present invention relates to a wire saw for cutting brittle materials such as silicon, glass, and ceramics.

[0002]

2. Description of the Related Art In general, when a workpiece is cut by a wire saw, the workpiece is vertically pressed against a traveling wire row and cut. In this wire saw, in order to cut the workpiece with high accuracy, it is important to supply a sufficient amount of slurry to the contact portion between the workpiece and the wire and keep the cutting resistance constant.

However, when a cylindrical workpiece is cut with the wire saw, the length of the contact portion between the workpiece and the wire changes depending on the cut portion of the workpiece. There is a problem that the warpage and the thickness vary. That is, there is no problem because the contact length with the wire is short at the beginning and end of cutting of the workpiece, but the contact length increases as the vicinity of the center is cut, and the slurry is not sufficiently supplied inside. There was such a problem. In addition, there is also a problem that the cutting resistance increases as the contact length increases.

As means for solving such a problem, as disclosed in JP-A-57-75765 and JP-A-8-85053, cutting is performed while swinging a workpiece with respect to a wire row. There is a way to do that. According to this cutting method, since the workpiece comes into contact with the wire in an arc, even when the center of the workpiece is cut, the slurry can be sufficiently supplied to the inside and the cutting resistance can be reduced. Can also be kept within a certain range.

[0005]

In the apparatus disclosed in Japanese Patent Application Laid-Open Nos. 57-75765 and 8-85053, a workpiece is attached to the tip of a swingable arm. By swinging the arm, the workpiece is swung. Therefore, the swing center is configured to be separated from the axis of the workpiece.

However, if the swing center is set at a position distant from the axis of the workpiece as described above, when the workpiece is cut with a constant swing angle, the wire is cut at the beginning of the workpiece. And the workpiece do not come into contact with each other.
For this reason, there is a problem that the cutting accuracy of the portion at the start of cutting is reduced, and cracks and chips are generated. In order to prevent such a situation from occurring, the swing angle must be properly controlled in accordance with the amount of cut so that the workpiece always contacts the wire. In a configuration in which the axis of the workpiece is far from the axis, such control becomes extremely difficult.

[0007] By swinging the arm,
Since the workpiece is oscillated, the rigidity of the arm and the like must be taken into consideration, and there is a disadvantage that the apparatus becomes large and complicated. The present invention has been made in view of such circumstances, and an object of the present invention is to provide a wire saw that can perform stable swing cutting of a workpiece with a simple mechanism.

[0008]

According to the present invention, in order to achieve the above object, a work feed table on which a workpiece is mounted is fed toward a traveling wire row, and the workpiece is put on the wire row. In a wire saw that presses and supplies a processing liquid containing abrasive grains to a contact portion between the workpiece and the wire row, and cuts the workpiece into a large number of wafers, the work feed table includes the workpiece And a swing means for swinging the workpiece along the wire running direction of the wire row around a center point of the shaft or a point near the shaft center.

According to the present invention, the workpiece swings around its axis or one point near the axis. Therefore, even at the beginning of cutting of the workpiece, the workpiece can always be brought into contact with the wire, and occurrence of chipping or the like can be prevented. Also, the configuration can be simplified. Further, even when cutting is performed by changing the swing angle in accordance with the feed amount of the workpiece, the control can be performed very easily.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a wire saw according to the present invention will be described below in detail with reference to the accompanying drawings.
FIG. 1 is a perspective view showing the entire configuration of the wire saw 10. As shown in the drawing, a wire 14 wound around a wire reel 12 passes through a wire running path formed by a number of guide rollers 16, 16,.
It is wound around 18B, 18C to form a horizontal wire row 20. The wire 14 having the wire row 20 formed thereon is wound on a wire reel (not shown) via a wire running path on the other side formed symmetrically with respect to the wire row 20.

A wire guide device 22, a dancer roller 24, and a wire cleaning device 26 are provided on each of the wire running paths formed on both sides of the wire row 20 (only one side is shown). The wire 14 is guided from the wire reel 12 at a constant pitch. The dancer roller 24 applies a certain tension to the traveling wire 14, and the wire cleaning device 26
4 is removed from the wire 14.

The pair of wire reels 12 and the grooved rollers 18C are connected to motors (not shown) that can rotate forward and reverse, respectively. It reciprocates between the reels 12 at high speed. A work feed table 28 that moves vertically with respect to the wire row 20 is installed above the wire row 20. An ingot 30, which is a workpiece, is attached to the work feed table 28, fed by the work feed table 28, and pressed against the wire row 20. At the time of cutting, the ingot 30 The feed is given while being rocked by a rocking mechanism 32 provided on the table 28. Hereinafter, the swing mechanism 32
Will be described.

FIG. 2 is a front view showing the structure of the swing mechanism 32, and FIG. 3 is a sectional view taken along the line AA of FIG. As shown in FIG.
4. The swing frame 36, the swing drive motor 38, and the work holding unit 40 are configured as main constituent members.

The support frame 34 is formed in a gate shape, and its upper end is formed on the work feed table 28.
Is fixed to the lower surface of the. The swing frame 36 is formed in a gate shape like the support frame 34, and is disposed inside the support frame 34. Horizontal rotating shafts 42, 42 are coaxially fixed to the legs 36a, 36a of the swing frame 36. Rotating shafts 42, 4
2 is rotatably supported by legs 34a, 34a of the support frame 34 via bearings (not shown), whereby the swing frame 36 is supported by the support frame 3
4, swings around the rotation shafts 42, 42.

As shown in FIG. 3, when the swing frame 34 swings, the upper end surface 36b of the swing frame 34 is fixed so that the swing frame 34 and the support frame 34 do not contact each other. The inner ceiling surface 34b of the support frame 34 is formed with a concave arc surface. The swing drive motor 38 is a motor for swinging the swing frame 38. The swing drive motor 38 is fixed to the support frame 34, and the spindle thereof is connected to one rotation shaft 42 (the right side in FIG. 2) fixed to the swing frame 34.

The work holding unit 40 holds the ingot 30 and is disposed on the inner ceiling surface of the swing frame 36. By the way, as shown in FIG. 3, a slice base 44 is adhered to the upper end of the ingot 30 along its axial direction, and a work block 46 is further adhered to the slice base 44. When the ingot 30 is mounted on the work holding unit 40, the work is carried out via the work block 46. Therefore, the work holding unit 40
Is configured as follows.

As shown in FIG. 2, the work holding unit 40 has a base 48, and the base 48
The swing frame 36 is fixed to the inner ceiling surface.
A work holding block 50 is provided below the base 48. The work holding block 50 holds both ends of the work block 46 with hook-shaped arms 50a, 50a formed at both ends thereof. . The arm 50
The upper end surface of the work block 46 held by the pair of cylinders 5 a
By being pressed by 2, 52, it is fixed to the work holding block 50.

The oscillating mechanism 32 is constructed as described above. The ingot 30 mounted on the work holding unit 40 drives the oscillating drive motor 38 to oscillate the rotating shafts 42, 42. Swing as the center of motion.
Here, the ingot 30 is set to swing about the axis O of the ingot 30 as the swing center when swinging. That is, the rotating shafts 4 and 42 are positioned so that the axes of the rotating shafts 42 and 42 and the ingot 30 mounted on the work holding unit 40 are coaxial with each other.
2 and 42 are set.

The ingot 30 is set to swing in the same direction as the wire running direction of the wire row 20 when the ingot 30 swings. That is, the attached ingot 3
The work holding unit 50 is set so that the axis O of 0 is orthogonal to the wire running direction of the wire row 20. As a result, the ingot 30 is pivoted about its axis,
The wire array 20 swings along the wire running direction. Then, in this state, the work is fed toward the wire row 20 by the work feed table 28, and is pressed against the wire row 20 that runs at a high speed while swinging.

Here, a nozzle (not shown) is provided above the wire row 20. When an ingot 30 is pressed against the wire row 20, slurry is sprayed from the nozzle toward the contact portion. . Ingot 30
Is cut into a number of wafers W by a lapping action of abrasive grains contained in the injected slurry. The slurry used for processing the ingot 30 is the same as that of the wire row 2
The oil pan 54 installed below the oil pan 54 is collected, returned to the slurry tank 56, and circulated. At this time, the slurry absorbs heat generated during processing and rises in temperature,
The recovered slurry is circulated through the heat exchanger 58 and cooled to a constant temperature.

The operation of the embodiment of the wire saw according to the present invention configured as described above is as follows. First,
The ingot 30 to be processed is mounted on the work holding unit 40 of the swing mechanism 32. That is, the work block 46 to which the ingot 30 is adhered is held by the pair of arms 50a, 50a formed on the work holding block 50, and the upper surfaces thereof are pressed and fixed by the cylinders 52, 52.

When the ingot 30 is mounted on the work holding unit 40, the wire saw 10 is operated. That is, the wire reel 12 is driven to rotate, the wire 14 reciprocates, and the work feed table 28 is driven to lower the ingot 30 toward the wire row 20. At the same time, the swing mechanism 3
By driving the second swing drive motor 38, the ingot 30 mounted on the work holding unit 40 is swung.

By driving as described above, the ingot 30 swings along the wire running direction of the wire train 20 with its axis O as the swing center, and the wire train 20 running in this state. At a predetermined feed amount. As a result, the ingot 30 is pressed against the wire row 20 while swinging. On the other hand, a slurry (not shown) is sprayed from a nozzle (not shown) toward the contact portion between the wire row 20 and the ingot 30 on the wire row 20 against which the ingot 30 is pressed, and
The ingot 30 pressed against the wafer is cut into wafers by the lapping action of the abrasive grains contained in the injected slurry.

Here, since the ingot 30 is pressed against the wire row 20 while swinging, the ingot 30 and the wire row 20 come into contact with each other by an arc. As a result, even when the center of the ingot 30 is cut, the slurry can be sufficiently supplied to the inside and the wafer can be cut with high accuracy. Also, the cutting resistance can be kept within a certain range, and stable cutting can be performed.

Further, since the ingot 30 is swung about the axis O of the ingot 30 as the swing center, the ingot 30 and the wire row 20 always contact. That is, if the center of swing and the axis of the ingot 30 are separated from each other as in a conventional swing cutting device, the ingot 30 may or may not contact the wire row 20 at the beginning of cutting the ingot 30. There was a problem, causing chipping. However, since the ingot 30 is swung about the axis O of the ingot 30 as the swing center as in the present embodiment, the ingot 30 always comes into contact with the wire row 20 even at the start of cutting, and chipping or the like occurs. Does not occur.

Further, by swinging the axis O of the ingot 30 about the swing center, the wire saw 10 of the present embodiment is disclosed in the above-mentioned Japanese Patent Application Laid-Open Nos. 57-75765 and 8-85053. There is an advantage that the configuration is simpler than that of the device that is used. That is, in the devices disclosed in the above publications, the ingot 20 is attached to the tip of the swinging arm to swing the ingot 30, so that the rigidity of the arm must be enhanced. However, there is a problem that the size becomes large. In consideration of this point, in the device disclosed in Japanese Patent Application Laid-Open No. H8-85053, the arm is driven by a reciprocating crank. As a result, the device becomes complicated and large, and the control becomes extremely complicated. ing.

On the other hand, in the device disclosed in Japanese Patent Application Laid-Open No. 57-75765, the arm is configured to swing the ingot with its base end as the swing center.
When the ingot 30 is mounted on the tip of the arm, there is a disadvantage that an extremely large torque is required for driving the ingot 30 and a large motor is required. On the other hand, in the wire saw 10 of the present embodiment, since the ingot 30 is swung about the axis O of the ingot 30, it is not necessary to consider the rigidity of the holding portion, and the driving force is small even when driving. The ingot 30 can be easily swung by the torque. As a result, the configuration can be extremely simplified as compared with the devices disclosed in the above publications.

In the swing cutting, there is a method of cutting while keeping the swing angle constant throughout. However, it is a general method to vary the swing angle according to the feed amount of the ingot 30. In this case, by making the axis O of the ingot 30 coincide with the center of swing, control of the swing angle becomes extremely easy as compared with the devices disclosed in the above publications. In the above-described embodiment, the swing angle of the ingot 30 has been described as being constant throughout. However, by performing the following control, accurate cutting can be performed. That is,
As shown in FIG. 4, at the beginning of cutting (the state shown in FIG. 4A), the ingot 30 is fed without swinging, and the swing angle is increased as the feeding progresses (FIG. 4).
(State of (b)). Then, when cutting the central portion of the ingot 30, the swing angle of the ingot 30 is increased so that the swing angle is maximized (the state of FIG. 4C),
After passing through the center, the swing angle is gradually reduced (the state of FIG. 4D). At the end, that is, at the time of the slice-based cutting, the cutting is completed by converging so that the swing is eliminated.

By cutting as described above, the length of contact between the ingot 30 and the wire row 20 is kept constant over the whole time, and stable and accurate cutting can be performed. In the present embodiment, the axis O of the ingot 30 is set as the swing center. However, substantially the same effect can be achieved even if the center near the axis is set as the swing center.

When it is necessary to tilt the ingot 30 so that the cut wafer has a predetermined crystal orientation, the swing mechanism 3 of the wire saw 10 is used.
2 and a tilting device may be attached. That is, in the above embodiment, the work holding unit 40
Although the work holding unit 40 is provided directly on the inner ceiling surface of the swing frame 36, the work holding unit 40 may be provided on the inner ceiling surface of the swing frame 36 via a tilting device. At this time, it is necessary to configure the entire apparatus so that the axis of the ingot 30 before tilting attached to the work holding unit 40 coincides with the center of swing.

[0031]

As described above, according to the present invention,
Since the workpiece swings around its axis or one point in the vicinity of the axis, the swing angle is constant.
The workpiece can be cut while being in contact with the wire, and stable cutting can be performed. Also, the configuration is simplified. Further, even when cutting is performed by changing the swing angle according to the feed amount of the workpiece, the control can be performed very easily.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of a wire saw.

FIG. 2 is a front view of a swing mechanism.

FIG. 3 is a side view of the swing mechanism.

FIG. 4 is an explanatory view illustrating a cutting state of swing cutting.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Wire saw 12 ... Wire reel 14 ... Wire 16 ... Guide roller 18A-18C ... Grooved roller 20 ... Wire row 28 ... Work feed table 30 ... Ingot 32 ... Swing mechanism 34 ... Swing frame 36 ... Swing frame 38 ... Swing drive motor 40 ... Work holding unit

Claims (1)

[Claims] 1. A work feed table on which a workpiece is attached is fed toward a traveling wire row, the workpiece is pressed against the wire row, and a contact portion between the workpiece and the wire row is ground. In a wire saw that supplies a processing fluid containing grains and cuts the workpiece into a number of wafers, the work feed table has one point near an axis or an axis of the workpiece as a swing center. And a swinging means for swinging the workpiece along the wire running direction of the wire row.