JP2000024892A - Duplex head flat surface grinding device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate the possibility of worsening machining accuracy by monitoring the difference and fluctuation of the cooling liquid supply quantity to upper and lower grinding wheels. SOLUTION: Wattmeters 112a, 112b and a monitoring means 113 are connected to upper and lower grinding wheel rotatory-elevating mechanisms 12, 13. The wattmeters 112a, 112b detect power consumption of driving motors of the grinding wheel rotatory-elevating mechanisms 12, 13 and output signals corresponding to the power values to the monitoring means 113. The monitoring means 113 compares both power values from the wattmeters 112a, 112b and outputs a signal for stopping the driving force of the grinding wheel rotatory- elevating mechanisms 12, 13 in the case where the difference exceeds the specified power value.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a double-sided surface grinding apparatus for finely grinding both surfaces of a work, which is a hard and brittle material used for a semiconductor, in an ultra-precise and parallel manner.

[0002]

2. Description of the Related Art For example, in a double-headed surface grinding apparatus for grinding both surfaces of a work cut into a wafer, a pair of grinding stone holders arranged vertically opposed to each other are provided with grinding stones. Then, in a state where the grindstone of each grindstone holder is in contact with the surface of the work, both grindstones are rotated,
The work is ground. When the grinding process is performed, the coolant is supplied to the upper and lower grinding points. Then, whether or not the coolant is being supplied is determined by the operator based on whether the supply switch of the coolant supply means is in an on state or an off state.

[0003]

However, in the conventional apparatus, clogging occurs in the coolant supply path, or the pump for supplying the coolant breaks down, so that the coolant between the upper and lower grinding wheels is not provided. If there is a difference or fluctuation in the supply amount of the steel, there is a possibility that a difference occurs between the upper and lower grinding amounts, leading to a deterioration in processing accuracy.

The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to monitor the difference or fluctuation of the supply amount of the cooling liquid supplied to the grinding portion of each grinding wheel, thereby improving the processing accuracy. An object of the present invention is to provide a double-sided surface grinding device capable of preventing the possibility of deterioration.

[0005]

According to the first aspect of the present invention, a grindstone is arranged opposite to a pair of grindstone holders, a work is inserted between the two grindstones, and the grindstone is in contact with both surfaces of the work. In a double-sided surface grinding device that is configured to perform grinding by rotating a grindstone holder, a first driving unit that rotates one grindstone holder, a second driving unit that rotates the other grindstone holder, and one grindstone First coolant supply means for supplying coolant, second coolant supply means for supplying coolant to the other grindstone, detection means for detecting a coolant supply state for each grindstone, and rotating both grindstone holders When the coolant is supplied to the grinding portion in a state where the grinding is performed, a monitoring unit that monitors a coolant supply state for each grindstone detected by the detection unit for each grindstone is provided.

According to a second aspect of the present invention, in the double-ended surface grinding apparatus according to the first aspect, the detecting means measures the power consumption of each of the driving means. According to a third aspect of the present invention, in the double-headed surface grinding apparatus according to the second aspect, the monitoring means generates an alarm when a difference in power consumption between the two driving means exceeds a predetermined value. is there.

According to a fourth aspect of the present invention, there is provided the double-sided surface grinding apparatus according to the second or third aspect, further comprising control means for controlling the two driving means, wherein the monitoring means controls the power consumption of the two driving means. When the difference exceeds a predetermined value, a signal for stopping driving of both driving means is output to the control means.

According to a fifth aspect of the present invention, in the double-sided surface grinding machine according to the first aspect, the detecting means measures a supply amount of the coolant supplied from each coolant supply means to each grinding wheel. It is.

According to a sixth aspect of the present invention, in the double-sided surface grinding machine according to any one of the first to fifth aspects, the monitoring means sets a detection value detected by the detection means in advance. An alarm is generated when the value is smaller than the set value.

According to a seventh aspect of the present invention, in the double-sided surface grinding machine according to any one of the first to sixth aspects, the monitoring means sets in advance a detection value detected by the detection means. And a signal for not starting grinding is output to the control means of the driving means when the detected value is smaller than the specified value.

[0011]

Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings. Although the embodiments described below are preferred specific examples of the present invention, various technically preferred limitations are added thereto. However, the scope of the present invention is not limited to the following description in particular. Is not limited to these embodiments unless otherwise described.

FIG. 1 shows a double-sided surface grinding apparatus according to an embodiment of the present invention, which is provided with a lower frame 11, on which an intermediate frame 202 is fixed. An upper frame 201 is fixed to an upper portion of the intermediate frame 202. The first on the lower frame 11
A lower grinding wheel rotating / elevating mechanism 12 including a lower grinding wheel rotating driving unit as a driving unit and a work supporting mechanism 14 are provided, and an upper frame 201 includes an upper grinding wheel rotating / elevating mechanism 13 including an upper grinding wheel rotating driving unit as a second driving unit. Is equipped. The grindstone holders 18 and 19 are attached to the upper and lower grindstone rotary elevating mechanisms 12 and 13 so as to face each other. The rotation and feed of the two grindstone holders 18 and 19 in the lower grindstone rotating / elevating mechanism 12 and the upper grindstone rotating / elevating mechanism 13 are controlled by a control unit 101 as a control means.

As shown in FIG. 2 and FIG. 3, the two grindstone holders 18 and 19 are formed in a disk shape, and a mounting boss 26 is formed at the center of the back surface thereof. Whetstone holder 18,
A plurality of mounting screw holes 27 are formed in the mounting boss portion 19 and the mounting boss portion 26 so as to extend in the axial direction. In a state where the mounting boss portion 26 is fitted to the rotating shafts 12a, 13a of the respective grindstone rotating elevating mechanisms 12, 13, each of the mounting screw holes 27 and the rotating shafts 12a, 1
By screwing a bolt 29 to 3a, the respective grindstone holders 18 and 19 are attached to the respective grindstone rotation elevating mechanisms 12 and 13, respectively.

A recess 31 is formed at the center of the end surface of each of the grinding wheel holders 18 and 19, and a stepped mounting seat 32 is formed at the outer peripheral edge of the recess 31. A plurality of rectangular parallelepiped grinding stones 33 and 34 are bonded and fixed to the mounting seat 32 at intervals on the same circumference. Then, both grindstone holders 18 and 19 are rotated while the grindstones 33 and 34 are in contact with the upper and lower surfaces of the work 22 on the work support mechanism 14, respectively, whereby the upper and lower surfaces of the work 22 are simultaneously ground.
The work 22 is previously mounted on the work support mechanism 14 and is carried to the processing position.

As shown in FIG. 2 and FIG.
In correspondence with the grinding wheels 3 and 34, a plurality of circular supply passages 36 for supplying the coolant to the grinding wheel holders 18 and 19 are provided.
It is formed in an inclined state so as to be located on the outer peripheral side of the centrifuge 19. The inlet 36a of each common passage 36 is connected to the grindstone holder 1
8, 19 and the outer peripheral surface of the mounting boss portion 26 are formed so as to open. And at this entrance 36a,
The cooling liquid injected from a plurality of nozzles 37 disposed outside the grinding wheel holders 18 and 19 is taken in. The outlet 36b of each supply passage 36 is formed so as to open to the end face side of the grindstone holders 18 and 19, and the inlet 3b is formed.
The coolant introduced from the 6a side is sprayed toward the inner peripheral surfaces of the grindstones 33 and 34 as shown by the arrow A in FIG.

Further, as shown in FIGS. 2 and 3, a plurality of groove-shaped discharge passages 40 are formed at the outer peripheral edges of the end faces of the grindstone holders 18, 19 between the respective grindstones 33, 34.
Their inner ends open into recesses 31. And
The coolant sprayed from the supply passages 36 onto the inner peripheral surfaces of the grindstones 33 and 34 passes along the discharge passage 40 along with the grinding dust generated during grinding, and the outer peripheral side of the grindstone holders 18 and 19 (arrow B shown in FIG. 3). It is designed to be discharged and removed.

As shown in FIG. 1, the nozzle 37 is provided with lower and upper coolant supply pumps 1 as coolant supply means.
The cooling liquid supplied from each of the cooling units 10 and 111 is injected. Lower and upper coolant supply pump 11
0 and 111 are connected to the control unit 101 and the control unit 1
01 drives and controls the lower and upper coolant supply pumps 110 and 111.

Power meters 112a and 112b as detecting means and monitoring means 113 are connected to the upper and lower grinding wheel rotating and lifting mechanisms 12 and 13, respectively. Wattmeter 11
2a and 112b are upper and lower whetstone rotating / lifting mechanisms 12 and 13 respectively.
Rotation driving state, that is, the grinding wheel rotation elevating mechanism 12, 13
, And outputs a signal corresponding to the power value to the monitoring means 113. The monitoring means 113 compares the two power values from the wattmeters 112a and 112b, and generates an alarm when the difference d (shown in FIG. 4) exceeds a predetermined power value da. With it,
A signal for stopping the driving of the grindstone rotation elevating mechanisms 12 and 13 is output from the monitoring means 113 to the control unit 101.

The upper and lower coolant supply pumps 110 and 11
1 and the nozzle 37, a coolant supply path 115, 1
16 are connected. A flow sensor 1 as a detecting means for measuring the supply amount of the coolant is provided on both paths 115 and 116.
17a and 117b are provided. Before the start of the grinding process, each of the flow rate sensors 117a and 117b outputs the detection signal to the monitoring means 113. And monitoring means 1
13 compares each supply amount value detected by the flow rate sensors 117a and 117b with a preset supply value stored in the monitoring means 113, and when the supply amount value detected is smaller than this value. , An alarm is generated, and a signal for not starting grinding is output from the monitoring unit 113 to the control unit 101.

Next, the operation of the double-sided surface grinding apparatus configured as described above will be described. When performing the grinding process, the work 22 is inserted and arranged between the grindstones 33 and 34 of the upper and lower grindstone rotating / elevating mechanisms 12 and 13 while the work 22 is supported by the work support mechanism 14, and the work 22 is set. Next, the upper and lower coolant supply pumps 110 and 111 are turned on, and the supply of the coolant is started. At this start, if the coolant is not normally sent to the nozzle 37 due to clogging of the nozzle 37 or the like, the supply amount of the coolant is detected by the flow rate sensors 117a and 117b, and the signal is output to the monitoring means 113. Is done. When the detected supply amount value is smaller than the preset supply amount value, the monitoring unit 113 outputs a signal not to start grinding processing to the control unit 101 at the same time as generating an alarm. Thus, the grinding process is not started in a state where the supply of the cooling liquid is insufficient.

On the other hand, when the coolant is normally sent to the nozzle 37, the flow rate sensors 117a, 117
Based on the supply amount of the coolant from b, the monitoring unit 113 that has determined that the supply amount is the desired amount outputs a signal to start the grinding to the control unit 101. Then, the plurality of nozzles 37 disposed outside the grindstone holders 18 and 19 cause the grindstone holder 1
Cooling liquid is injected toward 8, 19, and grinding is started.

When the grinding process is started, the grindstones 33 and 34 of the upper and lower grindstone rotating / lifting mechanisms 12 and 13 are rotated. Subsequently, the grindstones 33 and 34 of the upper grindstone rotating / elevating mechanism 13 descend and approach the work 17, and both grindstones 33 and 34 are moved.
Thereby, both surfaces of the work 17 are simultaneously ground.

During grinding, wattmeters 112a, 112
“b” detects the power value of each of the upper and lower whetstone rotating / elevating mechanisms 12 and 13 and outputs the detected power value to the monitoring means 113. Here, for example, one of the upper and lower nozzles 37
If there is a difference in the supply amount of the cooling liquid due to the clogging, the grinding conditions of the upper and lower grindstones 33 and 34 are different, and a difference is generated in the rotational force due to the grinding resistance of each of the grindstone rotation elevating mechanisms 12 and 13. Along with this, there is a difference in power consumption. If the difference d between the power values of the grindstone rotation elevating mechanisms 12 and 13 is larger than the predetermined power value da, the monitoring means 113 determines that there is a difference or a change in the supply amount of the coolant between the upper and lower portions. By this determination, the monitoring means 1
When the alarm 13 is generated and a signal for stopping the grinding is output to the control unit 101, the rotation drive of the grinding wheel rotating / lowering mechanisms 12, 13 is stopped, and the grinding is stopped.

On the other hand, the grinding wheel rotating and lifting mechanism 12, 1
If the difference d between the power values is smaller than the specified power value, the monitoring means 113 determines that the nozzle 37 is not clogged or the supply pump is normal and that the coolant is supplied without any difference or fluctuation between the upper and lower sides. . The monitoring of the supply state of the coolant is continued until the grinding process is completed.

The effects that can be expected from the above embodiment will be described below. (1) Both upper and lower grindstone rotating / elevating mechanisms 12 and 13 for rotating upper and lower grindstones 33 and 34, and both upper and lower both grindstone rotating / elevating mechanisms 1
Power meters 112a and 112b are provided as detecting means for detecting the rotational driving states of the motors 2 and 13. Then, when the coolant is supplied to the grinding portion while both the grinding wheels 33 and 34 are rotated, monitoring means for monitoring the rotational driving state of the grinding wheel rotating / lowering mechanisms 12 and 13 detected by the wattmeters 112a and 112b. 113 are provided.

For this reason, by detecting the driving state of the grindstone rotating / raising / lowering mechanisms 12 and 13, the difference and fluctuation of the supply amount of the cooling liquid between the upper and lower portions supplied to the grinding portions of the respective grindstones 33 and 34 are determined during the grinding process. , The processing accuracy can be prevented from being deteriorated.

(2) Since the wattmeters 112a and 112b measure the power consumption of each of the grindstone rotating / elevating mechanisms 12 and 13, it is possible to more reliably monitor the difference and fluctuation in the supply amount of the coolant between the upper and lower sides. Can be.

(3) For example, one of the upper and lower nozzles 37
If there is a difference in the supply amount of the coolant due to the clogging, the monitoring unit 113 determines that there is a difference or a change in the supply amount of the coolant between the upper and lower sides. According to this determination, the monitoring means 113 generates an alarm. Therefore, it is possible to easily recognize that there is a difference or a change in the supply amount of the cooling liquid between the upper and lower portions during the grinding.

(4) Upper and lower whetstone rotating and lifting mechanisms 12, 13
Is provided, and when the difference d in power consumption between the respective grindstone rotating / elevating mechanisms 12 and 13 exceeds a predetermined power value da, the monitoring means 113 sends the signals to the grindstone rotating / elevating mechanisms 12 and 13.
A signal for stopping the rotation drive of the motor 13 is output to the control unit 101. Therefore, when there is a difference or a variation in the supply amount of the coolant supplied to each of the grinding wheels 33 and 34, the double-sided surface grinding device can be automatically stopped.

(5) The detecting means for detecting the state of supply of the coolant to each of the grindstones 33 and 34 includes the coolant supply pump 11
It comprises flow rate sensors 117a and 117b for measuring the supply amount of the cooling liquid supplied from 0, 111 to each of the grindstones 33, 34. Therefore, it is possible to reliably prevent the processing accuracy from being degraded despite the simple configuration and the inexpensive components.

(6) When the supply amount of the coolant is smaller than a preset supply amount, an alarm is generated by the monitoring means 113. Therefore, it is possible to easily determine whether the supply of the cooling liquid is insufficient before the grinding.

(7) If the supply amount value detected by the flow rate sensors 117a and 117b does not exceed a preset value, a signal not to start grinding is output from the monitoring means 113 to the control unit 101. . Therefore, the grinding process is started only when it is confirmed that a predetermined amount of the coolant is supplied, so that it is possible to reliably prevent the grinding in a dry state.

The above embodiment may be implemented as follows. -Instead of the flow rate sensors 117a and 117b, a pressure sensor for detecting the pressure of the coolant flowing on the coolant supply path is used.

If the difference between the flow rate values detected by the flow rate sensors 117a and 117b is larger than a predetermined flow rate value, it is determined that there is no difference or fluctuation in the supply amount of the coolant between the upper and lower sides, and the detected flow rate value If the difference is smaller than the predetermined flow rate value, it is determined that there is a difference or a change in the supply amount of the coolant. According to this configuration, the power meters 112a and 112b can be dispensed with, so that the configuration is simplified.

Next, technical ideas other than the claims that can be grasped from the embodiment will be described together with their effects. (1) The double-sided surface grinding according to any one of claims 1 to 4, wherein the detection unit measures a supply pressure of a coolant supplied from each coolant supply unit to each grindstone. Board. According to this configuration, it is possible to reliably prevent the processing accuracy from deteriorating.

[0036]

Since the present invention is configured as described above, it has the following effects. According to the first aspect of the present invention, it is possible to monitor the difference or fluctuation of the supply amount of the cooling liquid supplied to the grinding portion of each grinding wheel from the rotational driving state of each driving unit, so that the processing accuracy is deteriorated. The fear can be prevented.

According to the second aspect of the present invention, by detecting the power consumption of each driving means, it is possible to more reliably monitor the difference and fluctuation of the coolant supplied to the upper and lower grinding wheels by the cooling supply means. it can.

According to the third aspect of the present invention, the monitoring means generates an alarm when the difference between the power consumptions of the two driving means exceeds a predetermined value. It can be easily recognized that there is a difference or a variation in the amount.

According to the fourth aspect of the present invention, based on the monitoring of the power consumption of each driving means, when there is a difference or fluctuation in the supply amount of the cooling liquid supplied to the grinding portion of each grinding wheel, ,
The device can be shut down automatically.

According to the fifth aspect of the present invention, it is possible to reliably prevent the processing accuracy from deteriorating. According to the invention described in claim 6, an alarm is generated when the detection value detected by the detection means is smaller than a preset value. Therefore, whether the supply of the coolant is insufficient is determined. Can be easily grasped.

According to the seventh aspect of the present invention, the grinding process is started only when it is confirmed that the preset coolant is supplied, so that the grinding is performed in a dry state. Can be reliably prevented.

[Brief description of the drawings]

FIG. 1 is a configuration block diagram of a double-sided surface grinding device according to the present invention.

FIG. 2 is an enlarged plan view showing a grinding tool.

FIG. 3 is a sectional view taken along line 3-3 in FIG. 2;

FIG. 4 is a graph showing an example of a difference and a fluctuation in power consumption of both whetstone rotating and lifting mechanisms.

[Explanation of symbols]

12 ... Lower wheel rotating / raising / lowering mechanism (first driving means), 13 ...
An upper grinding wheel rotating / lowering mechanism (second driving means), 18, 19 ...
Grindstone holder, 22 ... Work, 33, 34 ... Grindstone, 112
a, 112b: power meter (detection means), 101: control unit (control means), 113: monitoring means, 117a, 117b
... Flow sensor (detection means)

Claims (7)

[Claims] Claims: 1. A grindstone is opposed to a pair of grindstone holders,
In a double-sided surface grinding apparatus in which a work is inserted between the two grindstones and the grindstone is rotated by rotating the grindstone holder in a state where the grindstones are in contact with both surfaces of the work, a first drive for rotating one grindstone holder Means, second driving means for rotating the other grindstone holder, first coolant supply means for supplying a coolant to one grindstone, and second coolant supply means for supplying a coolant to the other grindstone Detecting means for detecting a coolant supply state for each grindstone; and a coolant supply state for each grindstone detected by the detect means when the coolant is supplied to a grinding portion while both grindstone holders are rotated. Double-sided surface grinding device comprising: 2. The double-sided surface grinding apparatus according to claim 1, wherein said detecting means measures power consumption of each of said driving means. 3. The double-sided surface grinding apparatus according to claim 2, wherein the monitoring unit generates an alarm when a difference between the power consumption of the two driving units exceeds a predetermined value. 4. A control unit for controlling both of the driving units, wherein the monitoring unit is configured to stop driving of both of the driving units when a difference in power consumption between the two driving units exceeds a predetermined value. 4. The double-sided surface grinding device according to claim 2, wherein the double-sided surface grinding device outputs the value to the control means. 5. The double-sided surface grinding machine according to claim 1, wherein the detecting means measures a supply amount of the cooling liquid supplied from each cooling liquid supply means to each grinding wheel. 6. The apparatus according to claim 1, wherein the monitoring unit generates an alarm when a detection value detected by the detection unit is smaller than a preset value. Double-sided surface grinder. 7. The monitoring means compares a detection value detected by the detection means with a preset specified value, and outputs a signal not to start grinding when the detected value is smaller than the specified value. The double-sided surface grinding machine according to any one of claims 1 to 6, wherein the double-sided surface grinding machine outputs a signal to a control unit of a driving unit.