JPH10119033A - Temperature controlling method for wire saw - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a temperature controlling method for a wire saw, with which condensation is prevented from occurring and an efficient temperature controlling can be performed. SOLUTION: A cooling water fed from the outside a wire saw is branched in the main body of the wire saw 10 into two systems of feed lines or a low temperature line 48A and a temperature controlling line 48B. The cooling water running in the low temperature line 48A is distributed and fed to apparatuses, which are installed outside a working chamber 42 and do not trouble with condensation, such as a heat exchanger 38 and the like as it is or without the controlling its temperature. On the other hand, the cooling water running in the temperature controlling line 48B, after its temperature is controlled with a temperature controlling unit 50 up to a temperature higher than a dew point temperature, is distributed and fed to apparatuses, which are installed within the working chamber 42 and mindful of sweating, such as the bearing units 19A-19C of grooved rollers 18A-18C and the like. Thus, the condensation can be prevented from occurring, resulting in allowing to prevent an electric leakage from developing and a cutting accuracy from lowering.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wire saw temperature control method, and more particularly to a wire saw temperature control method for cutting brittle materials such as silicon, glass and ceramics.

[0002]

2. Description of the Related Art In a wire saw, a work is pressed against a row of wires running at a high speed, a slurry (a working fluid containing abrasive grains) is supplied to a contact portion between the work and the row of wires, and the work is wrapped by the wire. Is a device for cutting wafers into wafers. As described above, since the wire saw presses the workpiece against the row of wires traveling at a high speed and cuts, a large amount of heat is generated at the cutting portion. The heat generated in the cut portion thermally deforms a grooved roller or the like forming a wire row, which causes a reduction in cutting accuracy of the work. For this reason, in the wire saw, in order to suppress heat generation in the cutting portion, the slurry circulated to the cutting portion is controlled to a predetermined temperature by passing through a heat exchanger.

In addition, the heat source of the wire saw is not only the cut portion of the work, but also the motor for driving the grooved roller and the shaft support portion of the grooved roller generate high heat, which adversely affects the cutting accuracy of the work. ing. Therefore, water-cooled motors and bearings are used to suppress heat generation.

[0004]

However, in the conventional wire saw, the cooling water supplied to the heat exchanger and the cooling water supplied to the motor and the like are all supplied with the same cooling water. Had problems. That is, the cooling water supplied to the heat exchanger is generally set to a low temperature (in the range of 5 ° C. to 15 ° C.) in consideration of the temperature control capability of the slurry and the generation of bacteria when the water is circulated. When cooling water of the same temperature is supplied to a motor or the like,
There was a risk of dew condensation occurring on the motor, resulting in electric leakage and the like. In addition, when dew condensation occurs on the shaft support portion, when an oil-based slurry is used, water is mixed into the slurry, and there is a problem that cutting performance is reduced.

The present invention has been made in view of such circumstances, and has as its object to provide a wire saw temperature control method capable of preventing the occurrence of dew condensation and performing efficient temperature control. I do.

[0006]

According to the present invention, in order to achieve the above object, cooling water supplied from the outside of the apparatus is distributed and supplied to a heat exchanger and a heat source for cooling the slurry, and the heat exchanger and the heat source are provided. In the method for controlling the temperature of a wire saw for cooling the cooling water to a predetermined temperature, the cooling water supplied from the outside of the apparatus is temperature-adjusted to a predetermined temperature according to the supply destination, and then supplied to each supply destination.

According to the present invention, the cooling water supplied from the outside of the apparatus is supplied to each destination after the temperature is adjusted to a predetermined temperature according to each destination. So, for example,
By supplying cooling water whose temperature has been adjusted to a temperature higher than the dew point to equipment that does not like dew condensation, such as the shaft support portion of the grooved roller, dew condensation can be prevented.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of a wire saw temperature control method 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 FIG. As shown in FIG.
2 are wound around guide rollers 16, 16,
Are wound around three grooved rollers 18A, 18B, 18C through a wire running path formed by. A large number of grooves are formed at a constant pitch on the outer periphery of the three grooved rollers 18A to 18C, and the wire 14 is sequentially wound around the grooves to form a horizontal wire row 20 on the upper surface. Is formed.

The wire 14 wound around the grooved rollers 18A to 18C passes through a wire running path on the other side formed symmetrically with respect to the grooved rollers 18A to 18C, and passes through a wire on the other side (not shown). It is wound on a reel.
Here, the pair of wire reels 12 and the grooved roller 1
A motor (only the motor 21 connected to the grooved roller 18C is shown) is connected to each of the wires 8C.
4 runs at high speed between the pair of wire reels 12.

[0010] A wire guide device 22, a dancer roller 24, and a wire cleaning device 26 are disposed on the wire running paths formed on both sides of the wire row 20, respectively (only one side is shown). The wire guide device 22 is installed near both wire reels, and guides the wire 14 to be fed out from the wire reel 12 at a constant pitch on the payout side, and guides the wire 14 on the take-up side.
2 to guide the film to be wound at a constant pitch. Further, the dancer roller 24 applies a certain tension to the traveling wire 14, and the wire cleaning device 26 removes the slurry (working liquid) adhered during the processing from the wire 14.

Above the wire row 20, a wire row 2
A work feed table 28 that moves vertically with respect to 0 is installed. This work feed table 2
8, a tilting device 30 is provided, and an ingot 32, which is a workpiece, is held at a lower portion of the tilting device 30, and its tilt angle is adjusted. In the wire saw 10 configured as described above, the cutting of the ingot 32 is performed by pressing the ingot 32 against the wire row 20 traveling at high speed. At this time, a slurry is supplied to the wire row 20 from a slurry tank 36 via a nozzle (not shown), and the ingot 32 is cut into wafers by a lapping action of abrasive grains contained in the slurry.

The slurry supplied at the time of processing is collected in the slurry tank 36 via a slurry collection plate 34 provided below the wire row 20, and is circulated and used while replenishing the shortage. Further, the cutting of the ingot 32 is performed in a processing chamber 42 covered with a cover 40, as shown by a two-dot broken line in the figure, to prevent the slurry from scattering around.

By the way, as described above, ingot 3
No. 2 cuts the ingot 32 by contact with the wire row 20 running at a high speed, so that the contact portion generates high heat due to friction. The heat generated in the contact portion causes thermal deformation on the grooved rollers 18A to 18C forming the wire row 20 and the like, which is a factor of reducing the cutting accuracy of the work. For this reason, the slurry recovered in the slurry tank 36 is circulated and supplied to the heat exchanger 38 to be controlled at a constant temperature.

Further, heat generated from the motor 21 for driving the grooved roller 18C, heat generated from the bearing units 19A to 19C of the grooved rollers 18A to 18C, and the like also cause a reduction in work cutting accuracy. , The motor 2
1 and the bearing units 19A to 19C are of a water-cooled type to suppress heat generation. Here, the heat exchanger 38, the motor 21, and the bearing units 19A to 19C
The cooling water supplied from the outside of the wire saw 10 is distributed and used as follows.

A supply pipe 44 is connected to a water source (not shown) installed outside the apparatus of the wire saw 10, and the supply pipe 44 is connected to a cooling water supply port 46 formed in the apparatus body of the wire saw 10. ing. The cooling water supplied from this water source has a predetermined temperature (5 ° C.
(A range of 15 ° C) is supplied,
It is supplied into the apparatus body of the wire saw 10 via the supply pipe 44. Then, the cooling water supplied into the apparatus main body of the wire saw 10 is distributed to each supply destination in the apparatus main body through a cooling water supply pipe 48 provided in the apparatus main body.

Here, as shown in FIG. 1, the cooling water supply pipe 48 is branched into two lines in the apparatus main body of the wire saw 10. One line 48A (hereinafter, referred to as a “low temperature line 48A”) is a line that distributes cooling water supplied from a water source to each supply destination without adjusting the temperature, and is mainly installed outside the processing chamber 42. The cooling water is distributed and supplied to equipment such as a heat exchanger 38 which does not dislike dew condensation.

The other line 48B (hereinafter referred to as "temperature control line 48B") is a line for adjusting the temperature of the cooling water supplied from the water source to a predetermined temperature and then distributing the cooling water to each supply destination. Is performed by the next temperature adjusting unit 50. As shown in FIG. 1, the temperature adjustment unit 50 includes a heater 52, a temperature sensor 54, and a CPU.
56.

The heater 52 is connected to the temperature control line 48.
The cooling water flowing through B is heated. The temperature control line 48B
The cooling water flowing through the heater 52 is heated to a predetermined temperature by passing through the heater 52. The temperature sensor 54
Is installed downstream of the heater 52 and measures the temperature of the cooling water heated by the heater 52. The measured temperature of the cooling water is output to the CPU 56.

The CPU 56 controls the drive of the heater 52, and controls the drive of the heater 52 so that the temperature of the cooling water flowing through the temperature control line 48B becomes a predetermined temperature. That is, the temperature of the cooling water measured by the temperature sensor 54 is fed back,
The driving of the heater 52 is controlled so that the temperature of the cooling water heated by the above becomes a predetermined target value.

Here, the temperature of the cooling water to be heated by the heater 52 is set to a temperature higher than the dew point in order to prevent dew condensation on the equipment supplied with the cooling water. The cooling water whose temperature has been adjusted to a predetermined temperature by the temperature adjusting unit 50 is:
Through the temperature control line 48, mainly the processing chamber 42
It is distributed and supplied to devices such as the bearing units 19A to 19C of the grooved rollers 18A to 18C and the motor 21, which are installed in the inside, and which does not want to be condensed.

The cooling water supplied to each device is recovered via a recovery pipe (not shown) and discharged out of the wire saw 10. The temperature control method according to the present invention in the wire saw 10 configured as described above is as follows. Cooling water supplied to the apparatus main body of the wire saw 10 is supplied to a cooling water supply port 46 from a water source (not shown) via a cooling water supply pipe 44. In addition, the cooling water supplied from this water source has a predetermined temperature (range of 5 ° C. to 15) in advance.
The temperature-adjusted one is supplied.

The cooling water supplied to the cooling water supply port 46 is
In the apparatus main body of the wire saw 10, the supply line is branched into two supply lines, that is, a low-temperature line 48A and a temperature control line 48B, and distributed to each supply destination. Then, the cooling water flowing through the low-temperature line 48A is distributed and supplied to each supply destination without adjusting the temperature.

Here, as described above, the cooling water supplied from the water source is previously adjusted to a predetermined temperature (in the range of 5 ° C. to 15) and has a low temperature.
It is mainly distributed to and supplied to devices such as a heat exchanger 38 which is installed outside the processing chamber 42 and which does not dislike dew condensation. On the other hand, the cooling water flowing through the temperature control line 48B is
After passing through 0, the temperature is adjusted to a temperature higher than the dew point, and then distributed to each supply destination.

The cooling water whose temperature has been adjusted to a temperature higher than the dew point is mainly supplied to the bearing units 19A to 19C of the grooved rollers 18A to 18C installed in the processing chamber 42.
And the motor 21, etc., which are distributed and supplied to devices that do not like condensation.
As described above, the cooling water supplied to each device in the device body of the wire saw 10 absorbs heat generated therein,
It is collected through a collection pipe (not shown) and discharged outside the apparatus.

As described above, in the method for cooling a wire saw according to the present embodiment, an apparatus (for example, the processing room 42
Supply of cooling water whose temperature has been adjusted to a temperature higher than the dew point to the bearing units 19A to 19C of the grooved rollers 18A to 18C and the motor 21 installed in the inside thereof, thereby preventing the occurrence of dew condensation. Can be. As a result, it is possible to solve the drawbacks such as the electric leakage caused by the dew condensation and the cutoff performance caused by the mixing of the water in the oily slurry as in the related art.

In addition, a device which does not cause any trouble even if dew condensation occurs (for example, a heat exchanger 38 for exchanging heat of slurry)
) Can be supplied with low-temperature cooling water as before, so that the cooling capacity is not reduced. Further, since the supplied cooling water is always controlled at a constant temperature, the thermal deformation of the bearing units 19A to 19C can be kept constant. Thereby, highly accurate cutting can be performed.

In the present embodiment, the supplied cooling water is used by branching into two lines, but it may be branched into a plurality of lines. For example, in the case of branching into three systems, a temperature adjusting unit is provided in two of the branch lines so that cooling water heated to different temperatures can be supplied according to each supply destination. Thereby, the cooling water at the most suitable temperature can be supplied to each supply destination, so that efficient temperature control of the wire saw as a whole can be performed.

At this time, cooling water whose temperature is controlled separately is supplied to each of the bearing units 19A to 19C, and the temperature of the cooling water to be supplied is varied according to the temperature change of each of the bearing units 19A to 19C. Thereby, thermal deformation can be kept constant, and cutting with higher precision can be performed. In the present embodiment, as an example of a supply destination of the cooling water whose temperature has been adjusted, the bearing units 19A to 19C of the grooved rollers 18A to 18C installed in the processing chamber 42 are provided.
C, the motor 21 and the like are mentioned, but more effective temperature control is possible by supplying the support to the ingot 32 (tilting device 30 and work feed table 28) and the drive motor of the wire reel 12. become.

[0029]

As described above, according to the present invention,
Each supply destination of the cooling water is supplied with cooling water having a temperature most suitable for each supply destination. Therefore, for example, dew condensation can be prevented by supplying cooling water whose temperature has been adjusted to a temperature higher than the dew point to a portion where dew condensation is not desired, such as the shaft support portion of the grooved roller. Thereby, it is possible to prevent the occurrence of electric leakage due to dew condensation and a decrease in cutting accuracy caused by mixing of water in the oily slurry. Further, since the cooling water having the most suitable temperature can be supplied according to each supply destination, the temperature of the wire saw can be efficiently controlled.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an embodiment of a wire saw to which a temperature control method according to the present invention is applied.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Wire saw 14 ... Wire 18A-18C ... Grooved roller 19A-19C ... Bearing unit 21 ... Motor 38 ... Heat exchanger 42 ... Processing chamber 44 ... Cooling water supply pipe 46 ... Cooling water supply port 48 ... Cooling water supply pipe 48A ... Low-temperature line 48B Temperature control line 50 Temperature control unit 52 Heater 54 Temperature sensor 56 CPU

Claims (2)

[Claims] 1. A wire saw temperature control method for distributing cooling water supplied from outside the apparatus to a heat exchanger and a heat source for cooling a slurry, and cooling the heat exchanger and the heat source to a predetermined temperature. A method for controlling the temperature of a wire saw, comprising: adjusting the temperature of cooling water supplied from the outside to a predetermined temperature in accordance with a destination; 2. A temperature control of a wire saw for distributing cooling water controlled to a predetermined temperature supplied from the outside of the apparatus to a heat exchanger and a heat source for cooling the slurry, and cooling the heat exchanger and the heat source to a predetermined temperature. In the method, the cooling water supplied from the outside of the apparatus is branched into two supply lines, and the temperature of the cooling water flowing through one of the supply lines is heated to a temperature higher than the dew point, and heated to a temperature higher than the dew point. A method for controlling the temperature of a wire saw, characterized in that the cooling water is supplied to a device such as a shaft support portion of the grooved roller or a drive motor of the grooved roller, which does not condense dew.