JP4630497B2 - Filter device and suction device equipped with the filter device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a suction fluid filter device and a suction device including the filter device, which are preferably used in a semiconductor wafer grinding device, a dicing device and the like having a chuck table for sucking and holding a workpiece.
[0002]
[Prior art]
Processing devices such as a grinding device for grinding a semiconductor wafer and a dicing device for manufacturing a chip from a semiconductor wafer include a chuck table for sucking and holding a semiconductor wafer as a workpiece, and generates a suction force on the chuck table. A suction device is connected. This suction device also sucks the processing liquid during processing together with the air in the clean room where the processing device is installed. The fluid made up of sucked air, processing liquid, and the like is separated into air and liquid in the gas-liquid separation tank, and the separated air is returned to the clean room via the filter device, and the liquid is appropriately discharged to the drain.
[0003]
[Problems to be solved by the invention]
The conventional suction device of the form as described above has the following problems to be solved due to the filter device.
[0004]
(1) Damage to gas-liquid separation tank:
The filter device through which the separated air flows becomes clogged over time, resulting in poor air permeability. Therefore, when clogging increases, the internal pressure of the gas-liquid separation tank increases and the tank is damaged, which may cause problems such as leakage of liquid in the tank and contamination of the clean room.
[0005]
(2) Machining defects:
In order to detect an increase in pressure due to clogging of the filter device, there is a method in which a pressure switch for pressure detection is provided in the tank or the filter device, and the operation of the suction device is stopped when the pressure rises to a predetermined value. However, in this method, when the suction device stops during processing, the workpiece is not sucked and held, and processing failure occurs.
[0006]
(3) Relief valve:
There is a method of attaching a relief valve to relieve the rising pressure in the tank. However, a relief valve that can handle the maximum exhaust flow rate of the suction device becomes complicated, expensive, and exhaust piping is complicated. Furthermore, since it is difficult to notice that the relief valve has been opened, the replacement time of the filter element tends to be unclear.
[0007]
The present invention has been made in view of the above-mentioned facts, and its technical problem is that the pressure on the inlet side of the filter can be easily released even when the filter device is clogged. It is an object of the present invention to provide an improved filter device that can be easily recognized and has a simple structure. It is another object of the present invention to provide a suction device provided with the improved filter device and capable of preventing problems such as breakage of the suction device.
[0008]
[Means for Solving the Problems]
In the present invention, as a filter device that solves the above technical problem, a cylindrical filter member that is open at both ends, and a fluid inlet that supports one open end of the filter member and communicates with the inside of the filter member. A filter support body, a cover body that is detachable to close the other open end of the filter member, and a biasing means that elastically biases the cover body in a closing direction, the filter support body and the cover body Has a cylindrical shape with one end substantially closed, each closed end abuts each of the opening ends of the filter member, and each cylindrical portion is fitted on the outside of the filter member to form an annular flow path. is, the filter device is provided, characterized in that.
[0009]
Then, when the filter device is clogged, the pressure pushes the cover body against the urging force to release the pressure on the inlet side of the filter. Further, the clogging of the filter device can be easily recognized by the movement of the cover body. Furthermore, the structure is simple.
[0010]
In a preferred embodiment, the biasing means, the other end through the inside of the filter member at one end is attached to the filter support is supported by a shaft member passing through projecting the cover member slidably, filter cover member A spring member that presses toward is provided. Display means is provided for indicating that the cover body is separated from the open end of the filter member and the open end is in the open state. The display means is provided with a sign that appears as the cover body moves.
[0011]
Also, a fluid suction device mounted on a processing device that performs a predetermined processing on a workpiece while supplying a processing liquid, a pump that is connected to a fluid suction path and generates a suction force, and is sucked by the pump. A gas-liquid separation tank that is connected to a fluid delivery path and separates the fluid into a gas and a liquid, and the above-described filter device attached to an exhaust port of a discharge path that discharges the gas separated by the gas-liquid separation tank; There is provided a suction device characterized by comprising: In a preferred embodiment, the processing apparatus includes a chuck table for sucking and holding a workpiece, and the suction path is connected to the chuck table.
[0012]
And the pressure of a gas-liquid separation tank is released with the above-mentioned improved filter apparatus, and problems, such as damage, are eliminated.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described in more detail with reference to the accompanying drawings.
[0014]
Referring to FIGS. 1 to 3, the filter device generally indicated by numeral 2 supports a filter member 4 that is a filter element having both ends of a cylindrical shape and one open end of the filter member 4. The filter support body 6 having a fluid inlet 6a communicating with the inside thereof, the cover body 8 that can be freely contacted and closed that closes the other opening end of the filter member 4, and the cover body 8 is elastically biased in the closing direction. And an urging means 10 for performing the above.
[0015]
The filter member 4 is formed of a porous material such as polypropylene. Then, the fluid to be filtered flows from the inside to the outside.
[0016]
The filter support 6 has a cylindrical shape in which one end (the lower end in FIG. 2) is substantially closed, and an annular receiving portion 6b is formed at the closed end portion to which the opening end of the filter member 4 is abutted and supported. The fluid inlet 6a described above is formed at the center of the closed end, and a pipe fitting 6c is integrally attached to the fluid inlet 6a. The cylindrical portion of the filter support 6 has an annular flow path R through which the fluid that has passed through the filter member 4 is formed on the radially outer side of the filter member 4 with the cylinder length being substantially the same as the length of the filter member 4. Is fitted.
[0017]
Further, a shaft member 6e is erected on the filter support 6 so as to extend outward from the opening end of the cylindrical portion on a bracket 6d attached across the fluid inlet 6a. A male screw is formed at the protruding tip of the shaft member 6e.
[0018]
The cover body 8 has a cylindrical shape in which one end (the upper end in FIG. 2) is substantially closed, and the closed end abuts against the opening end of the filter member 4 and closes the opening end so as to be able to contact and separate. A through-hole 8a through which the shaft member 6e is slidable is formed at the center of the closed end. The cylindrical portion of the cover body 8 is positioned between the filter member 4 and the cylindrical portion of the filter support 6 on the radially outer side of the filter member 4 with the cylindrical length being shorter than the length of the filter member 4. The above-mentioned annular flow path R is formed and fitted.
[0019]
The urging means 10 is a compression coil spring 10a which is a spring member attached to the filter support 6 and supported by a shaft member 6e whose other end penetrates the cover body 8 and presses the cover body 8 toward the filter member 4. It has. One end of the spring 10a is abutted against the cover body 8, and the other end is abutted against and attached to a nut 10b screwed into the male screw of the shaft member 6e.
[0020]
The valve opening pressure at which the cover body 8 separates from the opening end of the filter member 4 is determined by the mounting load of the spring 10a and the pressure receiving area of the cover body 8 obtained by subtracting the cross-sectional area of the shaft member 6e from the opening area of the filter member 4. Is set. Therefore, when the pressure inside the filter member 4 exceeds the set pressure, the cover body 8 is pushed away against the force of the spring 10a (this action will be further described later).
[0021]
The filter device 2 further includes display means 12 that indicates that the cover body 8 is separated from the opening end of the filter member 4 and the opening end is in the open state. The display means 12 includes a label 12 a as a mark provided on the cover body 8. The label “12a” is marked with “filter exchange” and is affixed to the end of the closed end of the cylindrical portion of the cover body 8. Therefore, the label 12a is normally hidden inside the cylindrical portion of the filter support 6, but appears visually when the cover 8 is pushed up (this effect will be further described later).
[0022]
The operation of the filter device 2 as described above will be described with reference to FIGS. 4 and 5 together with FIG.
[0023]
(1) Normal time (Fig. 2):
Referring to FIG. 2, the pressure of the fluid flowing in from the fluid inlet 6a, that is, the pressure inside the filter member 4 is lower than the pressure set by the biasing means 10, and the filter member 4 is usually less clogged. At times, the cover body 8 closes the open end of the filter member 4. As shown by the arrow, the fluid flowing in from the fluid inlet 6a is filtered through the filter member 4 from the inside to the outside, and passes through the annular flow path R formed by the outer cover body 8 and the cylindrical portion of the filter support body 4. Released outside the street.
[0024]
(2) When the inflow fluid exceeds a predetermined pressure (Fig. 4):
Referring to FIG. 4, when the clogging of the filter member 4 increases and the pressure inside the filter member 4 exceeds a predetermined pressure, the cover body 8 is pushed up against the urging means 10 and is lifted from the filter member 4. Separate and open. Then, as shown by the arrow, the fluid whose pressure has increased passes through this opening and is discharged to the outside through the outer annular flow path R. Therefore, by pushing up the cover body 8, the pressure inside the filter member 4 escapes to the outside, and further increase in pressure is suppressed.
[0025]
(3) Display means (FIG. 5):
When the cover body 8 is pushed up as described above, as shown in FIG. 5, the label 12a “filter exchange” of the display means 12 provided on the cover body 8 and hidden by the filter support body 4 appears, and the filter member 4 Is clogged and needs to be replaced.
[0026]
(4) Therefore, when the filter device 2 is clogged, the pressure on the inlet side of the filter device 2 can be easily released. Moreover, the state can be easily recognized. Furthermore, the structure is simple.
[0027]
With reference to FIG.6 and FIG.7, the suction apparatus provided with the above-mentioned filter apparatus 2 is demonstrated.
[0028]
First, with reference to FIG. 6, a semiconductor wafer grinding apparatus 14 which is a typical example of a processing apparatus provided with a suction device will be described. The grinding device 14 includes a rough grinding unit 22 via a pair of guide rails 20, 20 and a finish grinding unit 26 via a pair of guide rails 24, 24 on a support plate 18 erected on one end of the device housing 16. I have. A turntable 30 having three chuck tables 28 is provided on the upper surface of the apparatus housing 16, and the chuck table 28 is provided with a suction holding chuck 28a made of a porous ceramic plate in a circular recess opened upward. . A suction device 32 is connected to the chuck table 28.
[0029]
In the carry-in / carry-out area A, a semiconductor wafer as a workpiece is carried on the chuck table 28 by the carry-in means 36 from the pre-process part 34 and is held by suction. Then, by rotating the turntable 30, the chuck table 28 moves in the rough grinding region B and the finish grinding region C, and is ground while being supplied with the working fluid. The processed semiconductor wafer is carried out to the next process by the carry-out means 38 in the carry-in / out area A.
[0030]
The suction device 32 will be described with reference to FIG. The suction device 32 is connected to a fluid suction path 40 connected to the chuck table 28 to generate a suction force, and is connected to a fluid delivery path 44 sucked by the pump 42 to convert the fluid into gas and liquid. A gas-liquid separation tank 46 to be separated and a filter device 2 attached to an exhaust port 49 of a discharge path 48 for discharging the gas separated by the gas-liquid separation tank 46 are provided. The separated liquid is discharged to the outside through the drain hose 47.
[0031]
The operation of the suction device 32 including the filter device 2 as described above will be mainly described with reference to FIG.
[0032]
(1) Prevention of damage to gas-liquid separation tank:
In the suction device 32 provided with the filter device 2, when the filter member 4 of the filter device 2 is clogged, the cover body 8 of the filter device 2 opens away from the filter member 4 due to an increase in pressure (FIG. 4). Since the rise is suppressed, the gas-liquid separation tank 46 is prevented from being damaged. And the problem that the liquid in the tank 46 leaks out, the problem of dirtying the clean room, and the like are prevented.
[0033]
(2) Prevention of processing defects:
The suction device 32 provided with the filter device 2 does not stop the suction pump by detecting the pressure increase with a pressure switch as in the prior art, so that the suction device stops during processing and processing defects occur on the workpiece. Never do.
[0034]
(3) The clogging of the filter device can be easily recognized:
The suction device 32 including the filter device 2 can easily know the clogged state of the filter member 4, so that the replacement time can be easily known. Therefore, the operator can recognize that the filter is clogged and needs to be replaced, and can quickly replace the filter.
[0035]
As described above, the present invention has been described in detail based on the embodiments. However, the present invention is not limited to the above-described embodiments, and various modifications or corrections may be made within the scope of the present invention, for example, as described below. Is something that can be done.
[0036]
(1) Display means:
In the present embodiment, the display unit 12 of the filter device 2 is provided with a label 12a as a mark provided on the cover body 8, but as shown in FIG. 8, the cover body 8 is moved in the opening direction. There may be provided a limit switch 50 as a detection body for detecting the light and a lamp 52 that is turned on as a display body that operates based on the output thereof. Further, a buzzer, a monitor or the like (not shown) may be used as the display body. The operator can recognize the timing of filter replacement more reliably and can quickly replace the filter.
[0037]
(2) Filter support, cover body:
In the embodiment of the present invention, the cylindrical portion of the filter support 6 is placed outside the cylindrical portion of the cover member 8 on the outer side in the radial direction of the filter member 4 of the filter device 2, and the gas passing through the filter member 4 is annular. Although it was made to discharge | release upwards through the flow path R, conversely, gas can also be discharge | released below by making the cylindrical part of the filter support body 6 inside.
[0038]
【The invention's effect】
According to the filter device constructed according to the present invention, even if the filter device is clogged, the pressure on the inlet side of the filter can be easily released, and when clogged, it is easily recognized. Further, an improved filter device having a simple structure can be provided. Further, according to the suction device including the filter device configured according to the present invention, it is possible to provide a suction device in which problems such as breakage of the suction device are prevented.
[Brief description of the drawings]
FIG. 1 is a perspective view of a filter device constructed in accordance with the present invention.
FIG. 2 is a cross-sectional view taken in the direction of arrows AA in FIG.
3 is an exploded perspective view of the filter device shown in FIG. 1. FIG.
4 is a cross-sectional view showing an operating state of the filter device shown in FIG. 1. FIG.
5 is a side view showing an operating state of display means of the filter device shown in FIG. 1. FIG.
6 is a perspective view of a grinding device to which a suction device including the filter device shown in FIG. 1 is attached.
7 is a block diagram showing a configuration of the suction device shown in FIG. 6. FIG.
FIG. 8 is a view showing another embodiment of the display means of the filter device.
[Explanation of symbols]
2: Filter device 4: Filter member 6: Filter support 6e: Shaft member 8: Cover body 10: Biasing means 10a: Compression coil spring (spring member)
12: Display means 12a: Label
14: Grinding device 32: Suction device 40: Suction passage 42: Pump 44: Delivery passage 46: Gas-liquid separation tank 48: Discharge passage 49: Exhaust port 50: Limit switch (detector)
52: Lamp (display)
R: annular channel

Claims (7)

A cylindrical filter member opened at both ends, a filter support having a fluid inlet that supports one open end of the filter member and communicates with the inside of the filter member, and closes the other open end of the filter member A detachable cover body, and an urging means for elastically urging the cover body in the closing direction ;
The filter support body and the cover body have a cylindrical shape whose one end is substantially closed, each closed end portion abuts on each of the open ends of the filter member, and each cylindrical portion covers the outside of the filter member. A filter device, wherein an annular flow path is formed by fitting . The biasing means is a spring that has one end attached to the filter support body, is supported by a shaft member that passes through the inside of the filter member, and the other end slidably protrudes through the cover body, and presses the cover body toward the filter member. and a member, according to claim 1 Symbol placing of the filter device. The filter device according to claim 1 or 2 , further comprising display means for indicating that the cover body is separated from the open end of the filter member and the open end is in an open state. The filter device according to claim 3 , wherein the display means is provided with a sign that appears when the cover body moves. The filter device according to claim 3 , wherein the display unit includes a detection body that detects that the cover body has moved in the opening direction, and a display body that operates based on an output of the detection body. A fluid suction device attached to a processing device that performs a predetermined processing on a workpiece while supplying a processing liquid, a pump that is connected to a fluid suction path and generates suction force, and is sucked by the pump a gas-liquid separation tank for separating the fluid connected to the delivery path of the fluid into a gas and a liquid, from claim 1 attached to an exhaust port of the exhaust passage for discharging the gas separated by the gas-liquid separation tank 5 A suction device comprising the filter device according to any one of the above. The suction device according to claim 6 , wherein the processing device includes a chuck table for sucking and holding a workpiece, and the suction path is connected to the chuck table.

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