JP2016203319A - Wire saw, and manufacturing method of manufacturing plurality of sliced articles from workpiece using wire saw - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wire saw that has good processing precision by stably maintaining a roller temperature of the main roller at a target temperature without causing any abrupt variation in roller temperature of the main roller, and a manufacturing method using the wire saw.SOLUTION: A wire saw and a manufacturing method according to the present invention comprise: predicting variation in roller temperature based upon a variation amount ΔRm of a load of a motor during cutting work of a workpiece while noticing that a temperature T2 of a coolant supplied to a roller unit and a roller temperature of a main roller have substantially proportional relation; and maintaining the roller temperature at a target temperature by controlling the temperature T1 of the coolant supplied to the roller unit so as to cancel the variation.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a wire saw that cuts into a plurality of slices by a wire that travels a work made of a brittle material such as a semiconductor material, a magnetic material, and ceramics, and a manufacturing method that uses the wire saw to manufacture a plurality of slices from the work. .

This type of wire saw is described, for example, in Patent Document 1 below. The wire saw disclosed in Patent Document 1 includes a plurality of main rollers (grooving rollers) around which wires are wound, and a workpiece is cut into a plurality of slices by using a wire traveling between the main rollers.
Further, the wire saw disclosed in Patent Document 1 is a roller of a main roller in order to maintain a constant groove width of a groove in a main roller, that is, to maintain a constant thermal expansion of a polymer material layer that forms the outer periphery of the main roller. A temperature management means for managing the temperature is provided, and the temperature management means uses a coolant (polishing liquid), a heater, and a temperature sensor (thermocouple) to manage the roller temperature, and keeps the temperature of the main roller constant.

  Specifically, in the case of Patent Document 1, the heater preheats the main roller prior to the cutting process, and thereafter, when the cutting process by the wire saw is started, the frictional heat between the wire and the main roller and the bearing portion of the main roller By offsetting the main roller temperature rise caused by heat generation at the center by cooling the main roller with coolant, the roller temperature is maintained at the target temperature while being monitored by the temperature sensor.

JP 2002-18831 A

  By the way, since the temperature control means described above has a constant coolant temperature, it cannot respond quickly to the situation in which the roller temperature changes rapidly during cutting, and the roller temperature is stably maintained at the target temperature. Can not.

  The present invention has been made based on the above-described circumstances, and the object thereof is to provide a wire saw having a high processing accuracy by stably maintaining the roller temperature at the target temperature without causing a rapid change in the roller temperature. An object of the present invention is to provide a manufacturing method for manufacturing a plurality of slices from a workpiece using the wire saw.

The above objective is accomplished by a wire saw according to the present invention, which comprises:
A roller unit disposed between a pair of wire reels, which is fed from one of the wire reels and wound around the outer peripheral groove a plurality of times, and then the wire is wound around the other wire reel. A roller unit including at least a pair of main rollers to be led out and a motor that rotates the main rollers, and a temperature management device that manages the temperature of the main rollers,
The temperature management device is:
Monitoring means for monitoring changes in the load of the motor at the time of workpiece cutting;
Roller temperature adjusting means capable of adjusting the roller temperature of the main roller;
Control means for controlling the roller temperature to a target temperature via the roller temperature adjusting means according to the amount of change in the load of the motor obtained by the monitoring means.

  The wire saw of claim 1 was developed by paying attention to the fact that the change amount of the motor load is substantially proportional to the change of the roller temperature at the time of cutting the workpiece, and the change of the roller temperature from the change amount of the motor load. Based on the prediction result, the control means maintains the roller temperature at the target temperature via the roller temperature adjusting means.

For example, the roller temperature adjusting means uses a coolant for adjusting the roller temperature (Claim 2), and in this case, the control means is the temperature of the coolant before being supplied to the roller unit and after being supplied to the roller unit. Two temperature sensors that respectively detect the temperature of the coolant may be provided.
The present invention also provides a manufacturing method for manufacturing a plurality of slices from a workpiece using the above-described wire saw, and the manufacturing method will be apparent from the accompanying drawings and the following description relating to the configuration of the wire saw.

  The present invention according to claims 1 to 4 predicts a change in the roller temperature from the amount of change in the load of the motor, and adjusts the roller temperature based on the prediction result, thereby causing a rapid change in the roller temperature. The roller temperature can be stably maintained at the target temperature without any problem.

It is a schematic structure figure showing a wire saw of one embodiment concerning the present invention. It is the flowchart which showed the control procedure which the controller of FIG. 1 performs.

Referring to FIG. 1, the wire saw according to the first embodiment of the present invention includes a roller unit 10, and the roller unit 10 includes a pair of main rollers 12. These main rollers 12 can be rotated forward and backward by a motor 14, and are disposed apart from each other in the horizontal direction.
The roller unit 10 forms a pair with a pair of wire reels, and these wire reels can also rotate forward and backward, and are used as a supply reel or a take-up reel depending on the rotation direction.

The feeding reel feeds the wire 16 as it rotates, and the fed wire 16 is guided to the roller unit 10 through a guide roller, a direction changing roller, and the like. In FIG. 1, only the direction changing roller 18 disposed in the vicinity of the roller unit 10 is shown.
The wire 16 guided to the roller unit 10 is wound around the pair of main rollers 12 a plurality of times, and then wound around the take-up reel through the direction changing roller 18 and the guide roller similar to the above-described direction changing roller and guide roller. Taken. Here, a plurality of grooves for guiding the winding of the wire 16 are provided on the outer periphery of the main roller 12, and these grooves are formed in a polymer material layer that forms the outer periphery of the main roller 12.

Each wire reel is connected to a traverse control mechanism (not shown), and the traverse control mechanism reciprocates the corresponding wire reel in its axial direction, thereby stably feeding or winding the wire 16. to enable.
On the other hand, an elevating table 20 is disposed above the roller unit 10, and the work W is attached to the lower surface of the elevating table 20 via an adhesive layer 22 prior to cutting the work W.

On the other hand, a nozzle 24 is disposed immediately above the roller unit 10 so as to face the main roller 12, and this nozzle 24 is connected to a coolant supply tank 26 via, for example, a pump 28. Here, the coolant includes abrasive grains, or the abrasive grains are fixed to the wire 16 itself.
When the workpiece 16 is gradually lowered together with the lifting table 20 while the wire 16 is traveling in the roller unit 10, the workpiece W is cut into a plurality of slices by the wire 16 between the pair of main rollers 12. During the cutting process here, the coolant is discharged from the nozzle 24 toward the wire 16, and the discharged coolant contributes to the cooling of the wire 16 and the main roller 12.

The coolant used for cooling is collected in a coolant receiver 30, and the coolant receiver 30 is disposed between the main rollers 12. The used coolant in the coolant receiver 30 is processed and then returned to the supply tank 26.
During the cutting process described above, the roles of the pair of wire reels are alternately switched between the supply reel and the take-up reel, and at this time, the wires 16 that have reached the use limit are collected on one wire reel.

During the manufacturing process of the sliced product by the above-described manufacturing method, the wire saw of this embodiment further includes a temperature management device that manages the roller temperature of the main roller 12, and this temperature management device will be described below.
The temperature management device includes a coolant temperature adjuster 32 as roller temperature adjusting means, and this coolant temperature adjuster 32 adjusts the coolant temperature by cooling or heating the coolant in the supply tank 26. Such a coolant temperature regulator 32 is electrically connected to a controller 34, and in addition to the motor 14 of the roller unit 10, two temperature sensors 36 and 38 are electrically connected to the controller 34. . The temperature sensor 36 is disposed in the supply tank 26 and detects the coolant temperature T 1 of the coolant before being supplied to the roller unit 10, while the temperature sensor 38 is disposed in the coolant receiver 30 and is supplied to the roller unit 10. The coolant temperature T2 of the coolant is detected.

The controller 34 is a supply tank for maintaining the roller temperature at the target temperature based on the monitoring function for monitoring the load change in the motor 14 during the cutting of the workpiece W, the amount of change in the motor load, and the coolant temperature T1, T2. 26 has a control function of controlling the temperature of the coolant in the interior 26.
Details of the control function are shown in the control procedure of FIG. 2, and the control procedure will be described below.

  First, the controller 34 performs a preparatory process (step S1). In this preparatory process, the coolant temperature T1 is adjusted by the coolant temperature adjuster 32 and is kept at a predetermined preparatory temperature. The preparation temperature here is the prediction of the coolant temperature required for the coolant in the supply tank 26 in consideration of the coolant temperature rise when the coolant passes through the roller unit 10 when the roller temperature is maintained at the target temperature. Value.

Thereafter, the controller 34 determines whether or not the workpiece W is being cut (step S2). If the determination result is true (Y), the temperature sensor coolant temperatures T1 and T2 are read (step S3). It is determined whether or not the following equation is established (step S4).
K ・ T2 + C ≒ To (1)
In Equation (1), K is a proportional coefficient, C is a constant, and To is a target temperature of the roller temperature.

  Equation (1) indicates that the coolant temperature T2 in the coolant receiver 30 and the roller temperature are approximately proportional. Specifically, during cutting of the workpiece W, the wire 16 generates heat due to contact with the workpiece W and the main roller 12, and the heat generation here increases the roller temperature of the main roller 12. On the other hand, since the coolant is also heated by the contact with the wire 16, it is clear that the temperature of the coolant is also increased, and the present inventors have determined that the coolant temperature T2 after passing through the roller unit 10 is the main roller. It was found that it was roughly proportional to the roller temperature of 12, and the above (1) was obtained.

If the determination result of step S4 is true, the steps after step S2 are repeated, but if the determination result is false (N), the controller 34 reads the load Rm of the motor 14 (step S5), and Then, the change amount ΔRm of the load Rm is calculated from the change of the load Rm (step S6).
Here, since the change amount ΔRm of the load Rm has a correlation with the increase / decrease in the amount of heat generated when the workpiece W is cut, the controller 34 maintains the roller temperature at the target temperature To based on the change amount ΔRm. In the meantime, an increase / decrease amount ΔT of the coolant temperature T1 required for the coolant in the supply tank 26 is predicted (step S7).

Thereafter, the controller 34 determines whether the following expression (2) is true or false (step S8).
K · (T1 + ΔT) + C> To (2)
The expression (2) has the same meaning as the expression (1), but differs in that the target temperature To of the roller temperature is predicted by the coolant temperature (T1 + ΔT) in the supply tank 26.

If the determination result in step S8 is true, the controller 34 cools the coolant in the supply tank 26 via the coolant temperature regulator 32 based on the increase / decrease amount ΔT (step S9), while the determination result in step S8 is If false, the controller 34 heats the coolant in the supply tank 26 via the coolant temperature regulator 32 based on the increase / decrease amount ΔT (step S10).
Thereafter, unless the determination result in step S2 is false, the steps after step S2 are repeatedly performed, and the coolant temperature T1 in the supply tank 26 is controlled to maintain the roller temperature at the target temperature To.

  According to the above control procedure, the temperature T1 of the coolant in the supply tank 26 is controlled based on the change amount ΔRm of the load Rm in the motor 14, so this change amount ΔRm is substantially reflected in the change in the roller temperature. Never happen. Therefore, the controller 34 can stably maintain the roller temperature at the target temperature To without causing a rapid change in the roller temperature. As a result, the groove width of the groove in the main roller 12 is also maintained constant during the cutting of the workpiece W, and the slice processing of the workpiece W can be performed with high accuracy.

In this embodiment, since the temperature of the coolant is controlled, there is no need to incorporate a heater or a temperature sensor (thermocouple) in the main roller as in the wire saw of Patent Document 1, and the internal structure of the main roller 12 is not required. It can be easy to speak.
The present invention is not limited to the above-described embodiment, and various modifications can be made.
For example, the above equation (1) is merely a simple example that the coolant temperature T2 and the roller temperature of the main roller 12 are approximately proportional to each other. Needless to say, is included.

Further, the cooling / heating of the main roller 12 can be performed by, for example, incorporating a device such as a Peltier element in the main roller 12 without depending on the coolant.
Furthermore, the specific configuration of the wire saw itself can be arbitrarily changed without departing from the spirit of the present invention.

DESCRIPTION OF SYMBOLS 10 Roller unit 12 Main roller 14 Motor 16 Wire 24 Nozzle 26 Supply tank 30 Coolant receptacle 32 Coolant temperature regulator (roller temperature adjustment means)
34 Controller (monitoring means, control means)
36,38 Temperature sensor
W Work

Claims (4)

A roller unit disposed between a pair of wire reels, which is fed from one of the wire reels and wound around the outer peripheral groove a plurality of times, and then the wire is wound around the other wire reel. A roller unit including at least a pair of main rollers to be led out and a motor for rotating the main rollers;
In a wire saw equipped with a temperature management device for managing the temperature of the main roller,
The temperature management device is:
Monitoring means for monitoring changes in the load of the motor during workpiece cutting;
Roller temperature adjusting means capable of adjusting the roller temperature of the main roller;
A wire saw comprising: control means for controlling the roller temperature to a target temperature via the roller temperature adjusting means in accordance with a change in load of the motor obtained by the monitoring means.   The wire saw according to claim 1, wherein the roller temperature adjusting means uses a coolant for adjusting the roller temperature.   The said control means has two temperature sensors which each detect the temperature of the coolant before being supplied to the said roller unit, and the temperature of the coolant after being supplied to the said roller unit, It is characterized by the above-mentioned. Wire saw.   The manufacturing method which manufactures several slice goods from a workpiece | work using the wire saw in any one of Claims 1-3.

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