JP3455057B2 - Slurry circulation device and recording medium recording program for operating the device - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention uses a wire to
A semiconductor material, a slurry circulating system is So設wire saw for cutting a workpiece of hard and brittle materials such as ceramic, it relates to a recording medium recording a program for operating the 及 beauty slurry circulation device .

[0002]

2. Description of the Related Art In a wire saw, a plurality of processing rollers are arranged at predetermined intervals, and a plurality of annular grooves are formed at a predetermined pitch on the outer circumference of these rollers. Further, between the processing rollers, one wire is sequentially wound around the annular groove. Then, while the wire is running, an aqueous or oily slurry containing loose abrasive grains is supplied onto the wire, and in this state, the work is pressed against the wire and brought into contact therewith, and the work is cut and sliced into a wafer shape. To be done.

[0003]

By the way, when the work is sliced by the wire, chips are cut out from the work and mixed in the slurry. Then, as the work is sliced, the amount of chips mixed in the slurry increases, and the free abrasive grains contained in the slurry relatively decrease. As a result, the cutting ability with respect to the work is reduced, the cutting efficiency is reduced, and the shape accuracy of the sliced surface after processing is also reduced. Therefore, it is necessary to replace the new slurry at a constant rate or replace all the slurry to keep the ratio of loose abrasive grains contained in the slurry almost constant with respect to water or oil. is there.

However, in the past, since the replacement of the slurry was dependent on the intuition and experience of the operator, it was difficult to always maintain the ratio of the loose abrasive grains contained in the slurry at a substantially constant level.

The present invention has been made by paying attention to the problems existing in such a conventional technique, and its object is to keep the ratio of the free abrasive grains contained in the slurry substantially constant during cutting of the work. slurry circulation device capable of the invention is to provide a recording medium recording a program for operating the 及 beauty slurry circulation device.

[0006]

According to a first aspect of the present invention, a wire is wound between a plurality of processing rollers at a predetermined pitch, and while the wire is running, a slurry containing loose abrasive grains on the wire. Is provided on the wire saw, which is designed to cut the workpiece by contacting the work with the wire, and disperse the loose abrasive particles in the dispersion liquid to prepare the slurry from the slurry storage tank to the cutting part of the work. After the supply, the slurry circulation device that collects the slurry in the slurry storage tank and supplies it again to the cutting section, in the slurry circulation device, based on the information about the workpiece, is included in the slurry before or during the cutting or after the cutting. Based on the calculation result of the prediction calculation means for predicting and calculating the slurry life after cutting in order to keep the ratio of the abrasive grains constant, the slurry Slurry exchanging means for exchanging the slurry in the distilling tank with a new slurry is provided, and the slurry exchanging means is calculated by a product of a predetermined reference amount and a unit of the reference amount based on the calculation result of the prediction calculating means. The calculated amount exchange or the total amount exchange of all slurries is selectively performed .

[0007]

[0008]

[0009]

According to the invention of claim 2 ,
In the slurry circulation device described in 1 , the total amount exchange is performed when the unit of the reference amount exceeds the set value .

[0011] In the invention described in 請 Motomeko 3, claim
In the slurry circulation device according to 1, the slurry replacement means includes a slurry discharge means for discharging the slurry from the slurry storage tank to the slurry waste liquid tank, and a slurry replenishment means for replenishing new slurry from the slurry replenishment tank to the slurry storage tank. .

[0012] In the invention described in claim 4 is the slurry circulating system of claim 3, slurry discharge means operates prior to the slurry supply devices. According to a fifth aspect of the invention, in the slurry circulation device according to the third aspect, the slurry discharging means and the slurry replenishing means operate simultaneously.

[0013]

[0014]

According to a sixth aspect of the present invention, in the slurry circulation device according to any one of the first to fifth aspects, the prediction calculation means includes a bar code reader, and the bar code reader is a work. Information about the work is obtained by reading the barcode attached to.

According to a seventh aspect of the present invention, in the slurry circulation device according to any one of the first to sixth aspects, the slurry life represents a chip content rate in the slurry.

In the invention described in claim 8 , as a program for causing a computer to execute the operations of the prediction calculation means and the slurry exchange means in the slurry circulation device according to any one of claims 1 to 7. It is recorded.

In the embodiments of the invention described below, the "prediction calculation means" described in the claims or means for solving the problems corresponds to the control unit 51, and the "slurry replacement means" is also the same. The "slurry discharging means" corresponds to the slurry discharging means and the slurry replenishing means, and the "slurry discharging means" also includes the slurry supply pump 38, the supply pipe line 37, the branch pipe line 37a, and the first pipe.
It corresponds to the valve 38a and the second valve 38b, the "slurry replenishing means" also corresponds to the replenishment pipe line 46, the slurry replenishing pump 47 and the third valve 47a, and the "computer" also corresponds to the CPU 51a, the ROM 51b and the RAM 51c.
Equivalent to.

[0019]

DETAILED DESCRIPTION OF THE INVENTION

[First Embodiment] A first embodiment of the present invention will be described below with reference to the drawings.

First, the structure of the wire saw will be described. As shown in FIGS. 1 and 2, the cutting mechanism 11 is mounted on the device base 12. The cutting mechanism 11 includes a processing driving roller 13 and a processing driven roller 14 extending in parallel, and annular grooves 13a and 14a are formed at a predetermined pitch on their outer circumferences. In the drawings, the number of the annular grooves 13a and 14a is smaller than the actual number in order to facilitate understanding.

The wire 15 made of one wire is continuously wound around the annular grooves 13a and 14a of the working rollers 13 and 14, respectively. The wire traveling motor 16 is arranged on the apparatus base 12, and when the processing driving roller 13 is rotated by the motor 16, the processing driven roller 14 is rotated via the wire 15. The wire 15 is run at a predetermined running speed by the rotation of the processing rollers 13 and 14. The running of the wire 15 is performed so as to advance stepwise as a whole by repeating a certain amount of forward movement (for example, 10 m) and a certain amount of backward movement (for example, 9 m).

The work supporting mechanism 19 is supported above the cutting mechanism 11 by a column 20 erected on the apparatus base 12 so as to be movable up and down, and the work supporting mechanism 19 is made of a hard and brittle material under the column. 21 is detachably set. A work raising / lowering motor 22 is arranged on the column 20, and the work supporting mechanism 19 is vertically moved by the motor 22 via a ball screw or the like (not shown). Slurry supply mechanism 3
4 is provided above the cutting mechanism 11 so as to face it, extends in parallel with the processing rollers 13 and 14, and is provided with a plurality of slurry supply pipes 35 located on both front and rear sides of the work 21.

During operation of the wire saw, the work support mechanism 19 is lowered toward the cutting mechanism 11 while the wire 15 is running between the processing rollers 13 and 14 of the cutting mechanism 11. At this time, a water-based or oil-based slurry containing loose abrasive grains is supplied from the slurry supply pipe 35 of the slurry supply mechanism 34 onto the wire 15, and the work 21 is pressed against the wire 15 to make a lapping of the abrasive grains. The work 21 is cut into a wafer by the action. Therefore, the cutting portion 17 is composed of the processing rollers 13, 14, the wire 15 and the slurry supply pipe 35.

The reel mechanism 23 is mounted on the apparatus base 12, and is a reel 24 for reeling out the wire 15.
And a winding reel 25 for winding the wire 15. A pair of reel rotation motors 26 and 27, which are servo motors capable of changing the rotation direction and the rotation speed, are arranged on the apparatus base 12, and the reels 24 and 25 are attached to their motor shafts via a transmission mechanism (not shown). Each is connected.

The traverse mechanism 28 is the reel mechanism 23.
Is installed on the device base 12 adjacent to the
The feeding of the wire 15 from the wire 4 and the winding of the wire 15 on the winding reel 25 are guided while traversing up and down. Then, both reels 24, 2 of the reel mechanism 23
When the wire 15 is fed from the feed reel 24 to the cutting mechanism 11 by the rotation of the wire 5,
5 is wound on the take-up reel 25.

The tension applying mechanism 29 and the guide mechanism 30 are
It is arranged between the reel mechanism 23 and the cutting mechanism 11. Then, the processing rollers 13 and 14 of the cutting mechanism 11
Both ends of the wire 15 wound in between are hooked on the tension applying mechanism 29 via each guide roller 31 of the guide mechanism 30. In this state, the tension applying mechanism 29 applies a predetermined tension to the wire 15 between the processing rollers 13 and 14.

The tension reducing mechanism 32 is disposed between the reel mechanism 23 and the tension applying mechanism 29 and includes a pair of rotating rollers 33. Then, the wires 15 are hooked on these rotating rollers 33, and both rotating rollers 33 are rotated, so that the tension applying mechanism 29 to the reel mechanism 23.
The tension of the wire 15 that spreads to the reels 24, 25 side is reduced.

Next, the structure of the slurry supply mechanism 34 will be described. As shown in FIG. 3, a slurry storage tank 36 located under the wire saw stores an aqueous or oily slurry containing loose abrasive grains. This slurry is compounded outside the wire saw and added to an oily or aqueous dispersion as S.
Free abrasive grains such as iC are dispersed. A supply pipe line 37 as a pipe line is connected between the slurry storage tank 36 and the slurry supply pipe 35. The supply pump 38 is disposed in the supply pipe line 37, and the slurry in the slurry storage tank 36 is moved by the operation of the supply pump 38 from the slurry supply pipe 35 to the wire 15 through the supply pipe line 37.
Supplied on.

The first valve 38a is disposed in the supply pipe line 37, and the amount of slurry supplied to the slurry supply pipe 35 is adjusted according to the opening / closing amount of the first valve 38a. The second valve 38b is disposed in a branch pipe line 37a branched from the supply pipe line 37, and when the first valve 38a is fully closed,
By fully opening the second valve 38b, the slurry existing in the supply pipe line 37 is discharged to the slurry waste liquid tank 39 located outside the wire saw via the branch pipe line 37a.

The heat exchanger 40 is arranged on the downstream side of the supply pump 38 so as to be oriented in the vertical direction so as to surround the supply pipe line 37 extending in the vertical direction. Then, the slurry is cooled when passing through the supply piping 37 in the heat exchanger 40 from the lower part to the upper part. The flow meter 41 is arranged downstream of the heat exchanger 40 in the supply pipe line 37, and the flow rate of the slurry flowing in the supply pipe line 37 is measured by the flow meter 41.

The slurry recovery tank 42 has the cutting mechanism 11
A recovery pipe line 43 as a pipe line is connected between the slurry recovery tank 42 and the slurry storage tank 36. The recovery pump 44 is the recovery pipeline 4
3 is provided in the slurry recovery tank 4 from above the wire 15.
The slurry that has dropped inside 2 is returned to the slurry storage tank 36 via the recovery piping line 43 by the operation of the recovery pump 44.

A slurry replenishment tank 45 located outside the wire saw stores an aqueous or oily replenishment slurry containing loose abrasive grains, and a pipe is provided between the slurry replenishment tank 45 and the slurry storage tank 36. A supplemental piping line 46 as a line is connected. Fresh slurry is prepared in advance outside the slurry replenishment tank 45 and then supplied to the slurry replenishment tank 45. The replenishment pump 47 is arranged in the replenishment pipeline 46, and the slurry in the slurry replenishment tank 45 is operated by the operation of the replenishment pump 47.
And is supplied to the slurry storage tank 36 via the third valve 47a.

Next, a control circuit diagram of the slurry circulating device will be described. As shown in FIG. 4, the control circuit 50 includes a controller 51, liquid level sensors 36a, 39a, 42a, 45a of the tanks 36, 39, 42, 45, a bar code reader 52, a supply pump 38, a recovery pump 44, Replenishment pump 47, first valve 38a, second valve 38b, third
It is composed of a valve 47a. Liquid level sensor 3
6a, 39a, 42a, 45a are provided in each of the tanks 36, 39, 42, 45, and send a liquid level signal to the control unit 51.

The flow meter 41 measures the flow rate of the slurry flowing in the supply pipe line 37 and sends the measurement result to the control section 51. The control unit 51 is a CPU (Central Processing Uni
t) 51a, ROM (Read Only Memory) 51b, RAM
(Randam Access Memory) 51c, input key 51d, etc. The CPU 51a controls the entire control circuit 50. The ROM 51b stores a program for controlling the control circuit 50. The RAM 51c is composed of a flash memory or the like, and stores temporary data generated when the program is executed. The input key 51d includes a numeric keypad and the like necessary for input.

Liquid level sensors 36a, 39a, 42
a and 45a monitor the amount of slurry in each tank.
The barcode reader 52 reads the barcode attached to the surface of the work 21.

The supply pump 38, the recovery pump 44 and the replenishment pump 47 are constructed so as to operate based on a control signal from the control section 51. First valve 38a, second
The valve 38b and the third valve 47a are also configured to open and close based on a control signal from the control unit 51.

Next, the operation of the wire saw constructed as described above will be described. Now, in this wire saw,
The wire 15 is unwound from the unwound reel 24 of the reel mechanism 23, and is reciprocally run between the processing rollers 13 and 14 of the cutting mechanism 11 in a stepwise manner, and then is wound onto the take-up reel 25. Then, while the slurry containing loose abrasive grains is supplied from the slurry supply pipe 35 of the slurry supply mechanism 34 onto the wire 15 between the processing rollers 13 and 14, the work support mechanism 19 descends to the wire 15. The work 21 is pressed and brought into contact. As a result, the work 2
1 is cut into a predetermined thickness.

Next, a method of replacing the slurry in the slurry storage tank 36 will be described with reference to the flowchart shown in FIG. 6 to 11 as well as FIG.
The flowchart shown in (1) proceeds under the control of the CPU 51a based on the program stored in the ROM 51b of the control unit 51.

In S1, first, information on the work 21 (for example,
The diameter, length, slice thickness (in other words, wire pitch width equivalent, constant, etc.) is input to the control unit 51 by reading the barcode attached to the surface of the work 21 by the barcode reader 52. .

In S2, based on the information about the work 21, the chip content rate contained in the slurry is predicted and calculated as a specific means for expressing the slurry life after slicing. The method of predicting and calculating the chip content rate in S2 will be described later.

In S3, it is determined whether or not the predicted and calculated chip content rate is less than or equal to a preset specified value. When the chip content rate is equal to or lower than the preset specified value, the process proceeds to S8, and the slice processing is executed. When the chip content rate exceeds the preset specified value, the process proceeds to S4.

In S4, the chip content in the slurry when a certain amount of the slurry is replaced with a new slurry (quantitative replacement) is predicted and calculated. The method of predicting and calculating the chip content rate in S4 will be described later.

In S5, it is determined whether or not the chip content rate predicted and calculated in S4 is equal to or less than a preset specified value. If the predicted chip content is less than or equal to the preset specified value, the process proceeds to S6. If the chip content rate exceeds a preset specified value, it indicates that the amount of free abrasive grains in the slurry storage tank 36 has decreased to a level unsuitable for cutting. Then, the process proceeds to S7 and the slurry storage tank 36 All slurries inside are exchanged for new slurries (total exchange). The operation of the total amount exchange in S7 will be described later.

In S6, a quantitative exchange for exchanging a certain amount of the slurry in the slurry storage tank 36 is executed. The quantitative exchange operation in S6 will be described later.

At S8, the work 21 is sliced. Next, a method for predicting and calculating the chip content rate (%) contained in the slurry in S2 and S4 will be described.

In S1, the bar code information relating to the work 21 includes the diameter (D), the length (L) of the work 21, the slice thickness, that is, the pitch width (P) of the wire 15 and the constant (K). It has been written.

Here, if the amount of chips is M,     M = K * D * L / P ... (Equation 1) Indicated by. In addition, * shows a product.

Next, assuming that the chip content rate contained in the slurry is T and the total amount of the slurry is V, T = M / (V + M) * 100 ... (Equation 2)

Here, the ratio of the amount of chips (M) to the total amount of slurry (V) is represented by M << V (Equation 3), and therefore Equation 2 is T = M / (V + M) * 100≈M / V * 100 ... (Equation 4)

Therefore, in S2, the content of cutting chips contained in the slurry after slicing can be expressed by the equation (4). Next, assuming that the quantity of the slurry is X and the chip content rate in the case of quantitative exchange is TM, TM = (M- (X / V) * M) / V * 100 = (1-X / V) / V * M * 100 ... (Equation 5)

Therefore, the content of chips contained in the slurry in the case of quantitative exchange can be expressed by the equation (5). Next, the operation when the fixed amount of the slurry in the slurry storage tank 36 is exchanged (the operation of S6 in FIG. 5) will be described using the flowchart shown in FIG.

In S11, the first valve 38a is fully closed and the second valve 38b is fully opened. Then, the supply pump 38 starts discharging the slurry in the slurry storage tank 36 and transfers the slurry to the slurry waste liquid tank 39. At this time, the flow meter 41 measures the flow rate of the slurry flowing in the supply pipe line 37.

In S12, it is determined whether or not the flow rate of the slurry flowing through the flow meter 41 has reached a preset fixed amount. When the set fixed amount is reached, the flow meter 41 sends a signal indicating that the fixed amount of slurry has flowed through the flow meter 41 to the control unit 51.

In S13, the first valve 38a is fully opened and the second valve 38b is fully closed to stop the discharge to the slurry waste liquid tank 39. S1
In 4, the third valve 47a is fully opened and the slurry replenishing pump 47 is activated. Then, the slurry replenishment pump 47 starts replenishment of new slurry in the slurry replenishment tank 45, and the slurry is transferred to the slurry storage tank 36.

In S15, the slurry storage tank 36
Until a sensor signal is sent from the liquid level sensor 36a provided in the slurry storage tank 3
The slurry in 6 is replenished until it reaches a predetermined amount.

In S16, the slurry replenishing pump 47
Is stopped and the third valve 47a is fully closed. As a result, a fixed amount of the slurry in the slurry storage tank 36 is discharged to the slurry waste liquid tank 39, and the discharged fixed amount is replenished from the slurry replenishment tank 45, and the fixed amount of the slurry is exchanged.

Next, the operation when the entire amount of the slurry in the slurry storage tank 36 is replaced (operation of S7 in FIG. 5)
Will be described. Note that this control is also performed by the RO of the control unit 51.
CP based on the program stored in M51b
It is performed under the control of U51a.

To replace the entire amount of the slurry, first, all the slurry in the slurry storage tank 36 is discharged to the slurry waste liquid tank 39 by the supply pump 38. At this time, the slurry storage tank liquid level sensor 36a sends a signal to the control unit 51 to the effect that all the slurry has been exhausted from the slurry storage tank 36. Based on this, the replenishment pump 47 is activated.

Then, the third valve 47a is fully opened, and new slurry in the slurry replenishment tank 45 is replenished to the slurry storage tank 36 by the replenishment pump 47.
Then, a signal indicating that a predetermined amount of slurry is stored in the slurry storage tank 36 is sent to the control section 51 by the slurry storage tank liquid level sensor 36a.

Then, the control section 51 sends a signal to the supplement pump 47 to the effect that the supplement pump 47 is stopped, and the supplement pump 47 is stopped and the third valve 47a is fully closed.
As a result, all the slurry in the slurry storage tank 36 is discharged to the slurry waste liquid tank 39, and the slurry replenishment tank 4
A new slurry is replenished from 5.

As described above, according to the first embodiment, the following effects can be obtained. -Based on the information of the work 21, the cutting chip content rate contained in the slurry after the slicing of the work 21 is predictively calculated before cutting. Then, when the predicted and calculated chip content rate is equal to or less than the preset specified value, the slicing of the work 21 is executed. When the predicted and calculated chip content rate exceeds the preset specified value, the chip content rate when the slurry is quantitatively exchanged is predicted and calculated. When the chip content rate is less than or equal to the specified value, it is determined that the chip content rate contained in the slurry can be made equal to or less than the specified value by performing the quantitative exchange, and the quantitative exchange is executed.

However, when it is determined that the chip content rate exceeds the specified value even after the quantitative replacement, the cutting efficiency of the work 21 is better when the entire amount of the slurry is replaced than when the slurry is quantitatively replaced. Since the cost of slurries and slurries are economical, the entire exchange will be executed. Therefore, the swarf content does not exceed the specified value during the slicing of the work 21. Therefore, during cutting of the work 21, the ratio of loose abrasive grains contained in the slurry can be made substantially constant.
As a result, the cutting ability of the wire saw does not decrease.

The supply pump 38 for supplying the slurry to the wire 15 is used also when the slurry in the slurry storage tank 36 is discharged to the slurry waste liquid tank 39.
That is, the opening and closing of the first valve 38a and the second valve 38b is controlled by a control signal from the control unit 51, whereby the slurry is exchanged. Therefore, it is not necessary to provide a dedicated pump for discharging the slurry in the slurry storage tank 36 to the slurry waste liquid tank 39.

[Second Embodiment] Next, a second embodiment of the present invention will be described with reference to the flowchart shown in FIG. The description of the method of calculating the chip content rate calculated by the same method as in the first embodiment will be omitted.

In S21 to S23, the same processes as S1 to S3 in the first embodiment are performed. Then, in S23, when the calculated chip content rate is equal to or less than the specified value, the process proceeds to S31 and the slice processing is executed. If the calculated chip content exceeds the specified value,
The process moves to S24.

At S24, the slurry exchange unit is added. The addition of the slurry exchange unit is sequentially performed from "1", and the slurry exchange unit "1" corresponds to the number "1" of exchanges according to a predetermined fixed amount.

In S25, it is determined whether the added value of the slurry replacement unit in S24 is less than or equal to the set value. This set value is preset by the operator.
If the added value is less than or equal to the set value, the process proceeds to S26. If the added value exceeds the set value, the process proceeds to S30, and the entire amount of slurry is exchanged.

In S26, the amount of slurry to be exchanged is calculated from the product of the reference amount (corresponding to the fixed amount) and the added value of the slurry exchange unit in S24. That is, when the addition of the slurry exchange unit in S24 is executed for the first time, the slurry exchange unit is "1",
The amount of slurry to be replaced is the standard amount.

In S27, a predicted chip content rate is calculated when the slurry is replaced with the slurry amount calculated in S26. In S28, the above S2
It is determined whether or not the chip content rate predicted and calculated in 7 is less than or equal to a preset specified value. If the chip content rate is equal to or lower than the preset specified value, the process proceeds to S29, and the slurry exchange is executed with a calculated amount according to the product of the added value of the slurry exchange unit in S24 and the reference amount. To be done. If the chip content rate exceeds the preset specified value, the process returns to S24, and the slurry replacement unit is added to "2". And S26
In step S27, the amount of slurry to be exchanged is made twice as much as the reference amount, and in step S27, the chip content rate is predicted and calculated again. That is, each time the process returns to S24, the slurry replacement unit is added to increase the amount of slurry to be replaced. Then, the process proceeds to S29 only when the slurry replacement unit in S25 is less than or equal to the set value and the chip content rate in S28 is less than or equal to the specified value. Also, the slurry replacement unit is the set value (for example, "5")
If it exceeds, the process proceeds to S30.

In S30, the slurry storage tank 36
A total amount exchange will be performed to replace all the slurry inside. That is, it is more economical to cut the workpiece 21 and to reduce the cost of the slurry by performing the total amount exchange of the slurry than performing the total amount exchange of the slurry, and thus the total amount exchange is performed. It should be noted that the total exchange of the slurry is performed in the same manner as the total exchange of the first embodiment.

In S31, slicing of the work 21 is executed. In S32, the added value of the slurry replacement unit in S24 is cleared to prepare for the next slice processing of the work 21. Then, this process ends.

As described above in detail, according to the second embodiment, the following effects can be obtained in addition to the effects of the first embodiment.・ A standard amount for exchanging slurry is set, and the amount of slurry to be exchanged is calculated by adding the standard amount until the chip content rate falls below a specified value. Therefore, the amount of slurry to be replaced is calculated as a multiple of the reference amount. Therefore, if the reference amount and the set value are set such that the fixed amount in the first embodiment is the product of the reference amount and the set value, even if the fixed amount is not reached, the slurry exchange is executed. be able to. Therefore, more economical slurry exchange can be performed than in the first embodiment.

[Third Embodiment] Next, a third embodiment of the present invention will be described with reference to the flowchart shown in FIG. The description of the method of calculating the chip content rate calculated by the same method as in the first embodiment will be omitted.

In S41, S42 and S43, the same processes as S1 to S3 in the first embodiment are performed. Then, in S43, if the chip content rate is less than or equal to the specified value, the process proceeds to S48, and if the chip content rate exceeds the specified value, the process proceeds to S44.

In S44, the slurry replacement amount is calculated according to the chip content. The calculation method in S44 will be described later. In S45, the above S4
It is determined whether or not the slurry replacement amount calculated in 4 is less than or equal to a preset set amount. If the slurry replacement amount is less than or equal to the preset setting amount, the process proceeds to S46, and if the slurry replacement amount exceeds the set amount, the process proceeds to S47.

In S46, the slurry exchange amount calculated in S44 is discharged from the slurry storage tank 36 to the slurry waste liquid tank 39, and the same amount of new slurry as the discharge amount is supplied from the slurry replenishment tank 45 to the slurry storage tank 36. To replenish.

In S47, the entire amount of slurry is exchanged. That is, in S45, since the amount of exchanged slurry exceeds the set amount, the entire amount of slurry is exchanged. It should be noted that the total exchange of the slurry is performed in the same manner as the total exchange of the first embodiment.

In S48, slicing is performed on the work 21 and this process is terminated. Next, the S
A method of calculating the slurry replacement amount in 44 will be described.

Transforming Equation 5 of the first embodiment,
The exchange amount (X) of the slurry is represented by X = (1−TM * V / (M * 100)) * V ... (Equation 6).

Here, the slurry replacement amount (X) is the slurry replacement amount in the third embodiment. As described above in detail, according to the third embodiment, the first
In addition to the effects of the second embodiment, the following effects can be obtained.

Based on the information of the work 21, the chip content rate contained in the slurry after the slicing of the work 21 is predicted and calculated. When the predicted and calculated chip content rate exceeds a preset specified value, the slurry replacement amount to be replaced is calculated by Equation 6. Then, the calculated amount of slurry exchange is discharged from the slurry storage tank 36 to the slurry waste liquid tank 39, and the slurry storage tank 36 is replenished from the slurry replenishment tank 45, so that the chip content rate in the slurry storage tank 36 is constantly maintained. It is below the specified value. Further, when the calculated slurry exchange amount exceeds the set amount, all the slurry in the slurry storage tank 36 is discharged to the slurry waste liquid tank 39, and new slurry in the slurry replenishment tank 45 is replenished to the slurry storage tank 36. Then, the entire amount of slurry is exchanged. That is, since the amount of slurry to be replaced is predicted and calculated based on the information about the work 21, the slurry will not be unnecessarily replaced during the replacement of the slurry. Therefore, more economical slurry exchange can be performed than in the first and second embodiments.

[Fourth Embodiment] Next, a fourth embodiment of the present invention will be described with reference to the flowchart shown in FIG. The description of the method of calculating the chip content rate calculated by the same method as in the first embodiment will be omitted. In addition, in the flowchart of FIG.
The same processes as those in the flowchart of FIG. 5 are designated by the same reference numerals and the description thereof will be omitted.

The fourth embodiment differs from the first embodiment in the timing of executing the slicing of the work 21. That is, in S1, first, information about the work 21 (for example, diameter, length, slice thickness (in other words, wire pitch width equivalent), constants, etc.) related to the work 21 surface, etc., prior to slicing the work 21. The barcode attached to the barcode is read by the barcode reader 52 and input to the control unit 51.

In S51, slicing of the work 21 is executed. In S2 to S7, the same processing as in the first embodiment is executed. As described above, according to the fourth embodiment, the following effects can be obtained in addition to the effects of the first to third embodiments.

As soon as the input of the information about the work 21 is completed, the slicing of the work 21 is executed.
Then, during slicing of the work 21, the work 2
The chip content after slicing No. 1 is predicted and calculated. As a result, when the chip content rate exceeds the specified value in S3, the slurry exchange is executed immediately after processing, and the slurry state can be kept proper. In addition, in the case of the fourth embodiment, the setting of the specified value in S3 is set lower than the setting value in the first embodiment. Thereby, the slicing of the next work 21 can be started immediately.

[Fifth Embodiment] In the fifth embodiment, similar to the fourth embodiment, the timing for executing the slicing of the work 21 is different in the second embodiment.

That is, in the flowchart shown in FIG. 10, after the processing of S21 is completed, in S52,
Slicing of the work 21 is executed. S22-S3
In 0 and S32, the same processing as in the second embodiment is executed.

As described above, according to the fifth embodiment, the same effect as the effect of the fourth embodiment can be obtained in addition to the effect of the second embodiment. [Sixth Embodiment] In the sixth embodiment, as in the fourth embodiment, the timing for performing the slicing of the work 21 is different from that in the third embodiment.

That is, in the flowchart shown in FIG. 11, after the processing of S41 ends, in S53,
Slicing of the work 21 is executed. S42 to S4
In 7, the processing is executed as in the third embodiment.

As described above, according to the sixth embodiment, the same effect as the effect of the fourth embodiment can be obtained in addition to the effect of the second embodiment. The above-described respective embodiments can be modified and embodied as follows.

In order to express the slurry life, not only the chip content, but any other calculation means can be used as long as it is proportional to the work amount with respect to the work 21. Further, the information on the work 21 may include the number of work pieces processed in the processing schedule.

As shown by the chain double-dashed line in FIG. 3, a waste liquid pipe line 48 is provided branching from the immediate downstream side of the supply pump 38 to the slurry waste liquid tank 39, and a fourth valve 49a is provided in the branched waste liquid pipe line 48. Prepare With this configuration,
The slurry in the slurry storage tank 36 can be transferred to the slurry waste liquid tank 39 more quickly.

As shown by the chain double-dashed line in FIG. 3, a waste liquid pipe line 48 is provided which connects the bottom surface of the slurry recovery tank 42 to the slurry waste liquid tank 39, and a fifth valve 49b is provided in the waste liquid pipe line 48. With this configuration, the slurry in the slurry recovery tank 42 can be transferred to the slurry waste liquid tank 39 more quickly.

The information on the work 21 may be replaced with a bar code, and may be a list showing the information on the work 21. The information about the work 21 in this case may be input by the operator using the input key 51d of the control unit 51.

Two supply pumps 38, a recovery pump 44, and a replenishment pump 47 may be provided, and each pump may be operated alternately. With this configuration, the life of each pump is extended, and each pump 38, 44, 4
Even if one of the pumps 7 fails, the other pump can operate the wire saw. Moreover, a failed pump can be repaired while the wire saw is operating.

A manual switch for operating the supply pump 38, the recovery pump 44, the replenishment pump 47 and the first to third valves 38a, 38b, 47a, and the slurry storage tank 36, and the slurry waste liquid instead of the control unit 51. Tank 39,
Liquid level sensors 36a, 39a, 42a provided in the slurry recovery tank 42 and the slurry replenishment tank 45, respectively.
It may be configured with an alarm speaker that sounds an alarm when the operation of 45a is performed, and an operator may operate the manual switch provided on the control panel to exchange the calculated amount and the entire amount of the slurry.

In the exchange of the calculated amount and the total amount of the slurry, discharging from the slurry storage tank 36 to the slurry waste liquid tank 39 and supplementing from the slurry replenishment tank 45 to the slurry storage tank 36 may be performed at the same time. .

Further, technical ideas other than the claims understood from each of the embodiments will be described below together with their effects. ・ Slurry exchange means is a slurry circulation device that has a slurry replenishment tank for temporarily storing new slurry.

With this structure, it is possible to quickly replace the new slurry with the supplied slurry. ・ For the entire slurry exchange, the slurry circulation device obtains information for controlling the total exchange from the output of the sensor for detecting the amount of slurry stored in the slurry storage tank.

According to this structure, the slurry in the slurry storage tank can be kept at a predetermined amount. By the way, in the present specification, the recording medium may be any readable semiconductor storage device, a recording medium of a magnetic storage device, a recording medium of a magneto-optical storage device or the like as long as the computer program can be recorded. . Specifically, it includes a semiconductor ROM, a floppy disk, a hard disk, an optical disk, a magneto-optical disk, a phase change disk, a magnetic tape and the like.

[0101]

Since the present invention is constructed as described above, it has the following effects. According to the invention described in claim 1, by predicting and calculating the life of the slurry, the slurry replacement timing can be predicted, and the slurry replacement can be performed in good timing. Therefore, during cutting of the work, the ratio of the free abrasive grains contained in the slurry can be made substantially constant, and high cutting efficiency and accuracy of the sliced surface can be maintained. A wire saw equipped with a slurry circulation device that can automatically perform slurry replacement based on slurry life prediction and can keep the ratio of free abrasive grains contained in the slurry almost constant during cutting of a workpiece. Can be provided. In addition, if the slurry life after cutting is predicted and calculated before cutting, the ratio of free abrasive particles contained in the slurry during cutting of the workpiece will not increase sharply, and the cutting efficiency of the workpiece will not decrease. The work can be sliced with a constant sharpness. Further, if the prediction calculation result of the slurry life can be obtained during or after the cutting of the work, the slurry replacement based on the calculated amount is executed after the cutting of the work is completed,
The slurry state can be kept appropriate, and the cutting work of the next work can be started immediately. Further, it is possible to selectively execute the calculation amount exchange or the total amount exchange with the reference amount as one unit.

[0102]

[0103]

[0104] According to the invention described in 請 Motomeko 2, claim 1
In addition to the effect of the invention described in (1), if the unit of the reference amount exceeds the set value, the total amount is replaced, so that the slurry can be replaced according to the result of the prediction calculation of the chip content rate .

[0105]

[0106]

[0107] According to the invention described in claim 3, claim 1
In addition to the effect of the invention described in (1), since the entire amount of the slurry is exchanged by the slurry discharging means and the slurry replenishing means, it is possible to discharge all the slurry supplied to the cutting portion and replenish it with new slurry. .

According to the invention of claim 4 , claim 3
In addition to the effect of the invention described in (1), since the operation of the slurry replenishing means is executed after the operation of the slurry discharging means is executed, all the slurry supplied to the cutting portion is discharged, and then a new slurry is replenished. can do.

According to the invention of claim 5 , claim 3
In addition to the effect of the invention described in (1), since the operation of the slurry discharging means and the operation of the slurry replenishing means are performed at the same time, the slurry can be quickly replaced.

[0110]

[0111]

According to the invention of claim 6 , claim 1
~ In addition to the effect of the invention described in any one of claims 5 , information about the work by a bar code reader,
It can be easily and surely obtained.

According to the invention described in claim 7 , the work life can be easily predicted and calculated based on the work information.

According to the invention described in claim 8 , it is possible to automatically perform the slurry exchange based on the prediction of the slurry life, and the ratio of the loose abrasive grains contained in the slurry during the cutting of the work is almost equal. It is possible to provide a recording medium in which the operation of the slurry circulating device that can be kept constant is recorded as a computer program.

[Brief description of drawings]

FIG. 1 is a front view of a wire saw showing a first embodiment.

FIG. 2 is likewise a plan view of the wire saw.

FIG. 3 is a piping diagram showing a slurry supply mechanism of the wire saw.

FIG. 4 is likewise an electrical block diagram of the wire saw.

FIG. 5 is a flow chart showing quantitative exchange and total exchange.

FIG. 6 is likewise a flowchart showing a fixed amount exchange operation.

FIG. 7 is a flowchart showing calculation amount exchange and total amount exchange according to the second embodiment.

FIG. 8 is a flowchart showing calculation amount exchange and total amount exchange according to the third embodiment.

FIG. 9 is a flowchart showing a fixed amount exchange and a total amount exchange according to a fourth embodiment.

FIG. 10 is a flowchart showing calculation amount exchange and total amount exchange showing the fifth embodiment.

FIG. 11 is a flowchart showing calculation amount exchange and total amount exchange according to the sixth embodiment.

[Explanation of symbols]

Reference numeral 17 ... Machining section, 37 ... Supply pipeline that constitutes slurry discharge means, 37a ... Branch pipeline that constitutes slurry discharge means, 38 ... Supply pump that constitutes slurry discharge means, 38
a ... a first valve which constitutes a slurry discharging means, 38b ... a second valve which constitutes a slurry discharging means, 46 ... a replenishing pipe line which constitutes a slurry replenishing means, 47 ... a slurry replenishing pump which constitutes a slurry replenishing means, 47a ... A third valve that constitutes slurry replenishing means, 51 ... a control unit that functions as a prediction calculating means and a slurry exchanging means, 51a ... a CPU that constitutes a computer, 51b ... a ROM that constitutes a computer, 51
c ... RAM configuring a computer.

Claims (8)

(57) [Claims] 1. A wire is wound at a predetermined pitch between a plurality of processing rollers, and while the wire is running, a slurry containing loose abrasive grains is supplied onto the wire and a work is brought into contact with the wire. It is provided on a wire saw that is designed to perform cutting work, and after supplying a slurry prepared by dispersing free abrasive grains in a dispersion liquid from the slurry storage tank to the cutting part of the workpiece, the slurry is collected in the slurry storage tank. In the slurry circulating device that supplies the cutting part again to the cutting part, from the information on the work, before or during the cutting process, or after the cutting process, the cutting process is performed in order to keep the ratio of the free abrasive grains contained in the slurry constant. A predictive calculation means for predicting and calculating the life of the slurry and a slurry for replacing the slurry in the slurry storage tank with a new slurry based on the calculation result of the predictive calculation means. And the slurry exchange means, based on the calculation result of the prediction calculation means, the slurry exchange means exchanges the calculated amount calculated by the product of a predetermined reference amount and the unit of the reference amount or all the slurry. Slurry circulation device that selectively executes total exchange. 2. The slurry circulation device according to claim 1, wherein the total amount exchange is executed when the unit of the reference amount exceeds a set value. 3. The slurry circulating device according to claim 1, wherein the slurry exchange means is a slurry discharging means for discharging the slurry from the slurry storage tank to the slurry waste liquid tank, and a new slurry is replenished from the slurry replenishing tank to the slurry storage tank. Slurry recirculation device including a slurry replenishing means. 4. The slurry circulating device according to claim 3, wherein the slurry discharging means operates before the slurry replenishing means. 5. The slurry circulating device according to claim 3, wherein the slurry discharging means and the slurry replenishing means operate simultaneously. 6. The slurry circulation device according to claim 1, wherein the prediction calculation means includes a bar code reader, and the bar code reader reads the bar code attached to the work. A slurry circulation device that obtains information about the workpiece. 7. The slurry circulating device according to claim 1, wherein the life of the slurry represents a chip content rate in the slurry. 8. The program is recorded as a program for causing a computer to execute the operations of the prediction calculation means and the slurry exchange means in the slurry circulation device according to claim 1. Recording medium.