JPH0818244B2 - Wire displacement compensator for wire cutting machine - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a wire displacement correction device that corrects the displacement of a wire stretched in a wire-type cutting machine that simultaneously cuts a high hardness brittle material into a large number of wafers.

[Conventional technology]

There is a wire-type cutting machine that uses a high-speed traveling wire as one of means for simultaneously cutting the high hardness brittle material such as a silicon ingot into a large number of wafers at the same time. The outline is shown in FIGS. 5 and 6. This wire cutting machine 10
0 is a wire take-up reel which is paired with the wire S tensioning mechanism 101.
102 and 103 are provided. The wire tensioning mechanism 101 has, for example, three groove rollers 104, 105, 106 arranged in parallel, and annular grooves 104a, 105a, 106a having a predetermined pitch are formed in each roller, and a wire S is spirally wound along each annular groove. It is wound into a shape. Both ends of the wire S are wound around dancer rollers 107 and 108 and wound around take-up reels 102 and 103, respectively. The wire S wound on one reel, for example, the reel 102, is pulled out by the driving of the tensioning mechanism 101, is wound on the other reel 103, and the workpiece W is cut.
Is gradually raised, and the wire S traveling at a high speed is cut by the interaction of the working fluid containing abrasive grains.

[Problems to be solved by the invention]

At the time of cutting, the heat generated by the drive motor is transmitted to the machine frame, and a supporting bracket that supports the groove roller by a slight distortion of the side wall for attaching the tensioning mechanism 101 or cutting pressure
The position of the wire to be stretched may be distorted due to the bending of 111 and 112. For this reason, the wire may bite diagonally where it should be cut at a right angle to the axis of the object to be cut. Of course, this angle is small, but the wafer to be cut is required to have a very accurate cutting angle with respect to the axis (crystal axis) as well as the thickness. Therefore, at the time of cutting, in consideration of these things, measures such as adjusting the feed amount so as to reduce the cutting pressure are adopted, but it is inefficient and the quality is judged by the measurement after cutting. Is what
There are problems such as defective products.

[Means for solving problems]

In view of such a point, the present invention has an object to detect the relative displacement of the support table on which the object to be cut is placed and the wire at the cutting position through the bracket and automatically correct the displacement.
The feature is that a plurality of groove rollers are rotatably attached to a bracket, a wire is spirally wound around each groove roller, the wire runs at a high speed, and an object to be cut is gradually stretched. In a wire-type cutting machine that feeds to the wire side and cuts the object to be cut into a large number of wafers at the same time by the interaction with a working liquid containing abrasive grains, between the support base supporting the object to be cut and the groove roller support bracket. Is provided with a displacement detecting means for detecting lateral displacement of the bracket with respect to the ascending direction of the support base, and a moving means for pushing and pulling the bracket in a direction orthogonal to the wire tensioning direction, and the moving means is operated by a signal from the displacement detecting means. This is to correct the lateral displacement of the wire.

[Work]

The displacement of the wire is detected by the displacement detecting means via the bracket. Based on this detected amount, the bracket is corrected and moved by the moving means, thereby holding the wire at the correct cutting position.

〔Example〕

1 to 4 show an embodiment of the present invention. The wire tensioning mechanism 1 in the wire type cutting machine is provided with a plurality of groove rollers 2, 3, 4 forming a set and front and rear support brackets 5, 6 for supporting these groove rollers. As is well known, each groove roller is engraved with annular grooves at predetermined intervals and rotatably supported by a support bracket, and a cutting wire S is spirally wound around each groove roller. The support brackets 5 and 6 are attached to the machine side wall by appropriate mounting members 7 and 8, respectively.
It is detachably attached to F1. Reference numeral 10 is a machine base motor that drives an arbitrary groove roller, for example, the groove roller 2, and 11 is a support table that supports the object W to be cut. It gradually rises to the wire tensioning mechanism 1 side.

Reference numeral 20 denotes a displacement correction device for the wire S of the tensioning mechanism 1, which is provided between the support base 11 on which the workpiece W is placed and the support bracket 6 and the support bracket 6 and the support bracket 6.
And a moving means (22) for moving back and forth.

The displacement detection means 21 detects displacement of the tip of the support bracket 6 (opposite side to the side wall of the machine base).
It comprises a measuring plate 23 vertically mounted at a proper position on the support base 11 and a displacement measuring sensor 24 mounted on the support bracket 6. This sensor is composed of, for example, an overcurrent type displacement measuring device, and is mounted on the support bracket 6 by an arm 25.
It is attached to the tip of a support bar 26 that is inserted into and is supported by the support bar 26 so that the sensor 24 is closely supported to the measurement plate 23.

The moving means 22 includes a drive motor 31 attached to a frame rear wall F2 provided on the back surface of the tensioning mechanism 1 via an attachment frame 30, and a screw rod 32 rotated by the drive motor 31. The screw rod 32 is a screw cylinder 33 attached to the rear wall F2.
It is screwed into and the tip is rotatably connected to the support bracket 6. 34 is a flange attached to the screw rod 32, and 35 is a thrust bearing.

The drive motor 31 is a pulse motor, and the coupling 36
While rotating the screw 32 via the, the coupling 36 allows the screw rod 32 to move in the longitudinal direction.

Reference numeral 37 denotes a protective cylinder, one end of which is attached to the support bracket 6 and the other end of which is provided so as to face the frame rear wall F2 via a cushioning member 38.

In the above structure, when the object W to be cut is cut, the machine base motor 10 causes the wire S to travel at high speed through the groove rollers 2 to gradually raise the object W to be cut. Along with this, the measurement plate 23 also rises and the sensor 24 measures the distance between the sensor and the measurement plate 23, and the signal value is applied to a control mechanism (not shown). When the measured value changes, when the changed value, that is, the relative displacement exceeds the set value, the drive motor 31 is driven, and the screw rod 32 is rotated to press or pull the bracket 6. To move the bracket 6, the entire tensioning mechanism 1 is moved to the side wall F1.
The other end is moved with reference to the attachment part of. That is, the stretched wire is returned to the set position.

In the present embodiment, the sensor 24 is provided only at the tip of the tensioning mechanism 1, but the sensor 24 may also be provided at the base of the tensioning mechanism 1 (on the groove roller 3 side). The entire mechanism 1 may be movably supported via a linear motion ball bearing.

Further, the displacement detecting means 21 may be arranged such that the sensor 24 is attached to the support base 11 side and the vertical measuring plate is attached to the tensioning mechanism 1 side.

〔The invention's effect〕

According to the present invention, during the cutting work by the wire to be stretched, the relative displacement between the ascending / descending surface of the support table that constantly supports the object to be cut and the groove roller support bracket that stretches the cutting wire is detected and corrected. As a result, there is an effect that cutting can be performed accurately.

[Brief description of drawings]

1 to 4 relate to an embodiment of the present invention, FIG. 1 is an overall side view, FIG. 2 is a front view of a wire tensioning mechanism, and FIG. 3 is a cross section taken along the line I--I in FIG. 4 and 5 are longitudinal sectional views of the moving means, FIG. 5 is an overall explanatory view of the wire cutting machine, and FIG. 6 is a perspective view of a conventional wire tensioning mechanism. 2, 3 and 4 are groove rollers, 5 and 6 are support brackets, 11 is an object support base, 20 is a wire displacement correction device, 21 is displacement detection means,
22 is a moving means, S is a cutting wire, and W is an object to be cut.

Claims (1)

[Claims] 1. A wire comprising a plurality of groove rollers which are rotatably attached to a bracket, wound around each groove roller in a spiral shape, and run the wire at a high speed and gradually stretch an object to be cut. In a wire-type cutting machine that feeds to the side and simultaneously cuts the object to be cut into a large number of wafers by the interaction with the working liquid containing abrasive grains, between the support base supporting the object to be cut and the groove roller support bracket. Displacement detecting means for detecting lateral displacement of the bracket with respect to the ascending direction of the support base, and moving means for pushing and pulling the bracket in a direction orthogonal to the wire tension direction are provided, and the moving means is operated by a signal from the displacement detecting means. Wire displacement correcting means in a wire-type cutting machine, which is for correcting lateral displacement of a wire.