JPH11324923A - Double pump - Google Patents

Abstract

(57) [Problem] To provide a double pump in which a liquid and a working fluid for pressurizing the liquid are separated. SOLUTION: A double pump 1 of the present invention is a pump body in which a pair of spaces 12, 22 provided alongside pump bodies 3, 11, 21 are separated into two chambers by diaphragms 13, 23, respectively. 3, 11, 21 have input channels 31, 36 for inputting a liquid, and output channels 32, 37 for outputting a liquid, which are connected to respective pump chambers located inside the diaphragms 13, 23. , And exhaust holes 33 and 38 for discharging bubbles in the liquid, and suction and exhaust holes 34 and 39 for supplying a working fluid, which are communicated with the respective pressurizing chambers located outside the diaphragms 13 and 23. ing.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a double pump which is provided at a relay point for pumping liquid stored in a tank or the like to a discharge destination and is constituted by two pumps for continuously supplying liquid. Related to pumps.

[0002]

2. Description of the Related Art A clean room in which semiconductor manufacturing is performed is usually constructed on the second or higher floor of a building. Therefore, a chemical such as a resist solution used in a semiconductor manufacturing process is stored in, for example, an external tank of a factory, and is supplied to a clean room by drawing a line therefrom. At this time, a pumping means for pushing up the liquid chemical from below is required, and FIG. 3 is a block diagram showing a conventional liquid pumping means.

In this system, two tanks 51 and 61 are provided, and a chemical solution once supplied to these tanks is pressurized with an inert gas and sent to a clean room on an upper floor.
Therefore, the tanks 51 and 61 are connected to the chemical solution tank outside the factory via valves 52 and 62, while being connected to the clean room via valves 53 and 63. Further, a pressurizing line via valves 54 and 64 is provided to supply an inert gas for pressurizing the chemical liquid filled in the tanks 51 and 61. Furthermore, tanks 51 and 61
In order to remove air bubbles inside, piping is provided to the atmosphere side via valves 55 and 65.

When the chemicals are filled in the tanks 51 and 61 by opening and closing the valves 52 and 62, the valves 54 and 6 are opened.
4 is opened and an inert gas is supplied to pressurize the chemical solution. In the initial stage of pressurization, the valves 55 and 65 are opened and closed to discharge bubbles in the chemical, and subsequently, the valves 53 and 63 are opened and the chemical is pressure-fed to the clean room. Then, the valve 54,
At the same time as 64, the valves 55 and 65 are closed, and the supply of the chemical solution ends. The supply operation of such a chemical solution is performed in the tank 5
1 and 61 are not performed simultaneously, but are performed alternately.

[0005]

However, in the conventional method, since the chemical is directly pressurized by the inert gas, the inert gas dissolves in the chemical and foams in the secondary pipe, and the gas is produced by the bubbles. May cause malfunctions in the product. Also, by directly pressurizing the chemical solution with the inert gas, the chemical solution is diffused back into the gas supply line for supplying the inert gas,
Piping may corrode. In order to cope with such a problem, it is necessary to use expensive piping such as stainless steel or Teflon, and there has been a problem that the cost is high. In addition, since two tanks 51 and 61 need to be arranged, there is a problem that the installation area is increased.

Accordingly, an object of the present invention is to provide a double pump in which a liquid and a working fluid for pressurizing the liquid are separated from each other in order to solve such a problem.

[0007]

In the double pump of the present invention, a pair of spaces provided in the pump main body are separated into two chambers by diaphragms, respectively. , An input flow path for inputting a liquid, an output flow path for outputting a liquid, and an exhaust hole for discharging bubbles in the liquid, and located outside the both diaphragms. And a suction / exhaust hole for supplying a working fluid, which is connected to each of the pressurizing chambers. Therefore, the liquid is alternately discharged from the two diaphragm pumps formed in one pump main body. At this time, the pressure of the working fluid for pushing out the liquid acts via the diaphragm, and is filled in the pump chamber. Since the working fluid does not come into direct contact with the liquid, the gas used as the working fluid does not dissolve in the liquid, and adverse effects of air bubbles on the product are avoided.

Further, in the double pump of the present invention, the pump main body includes a central panel provided with the input flow path, the output flow path, and the exhaust hole, and a pair of side panels provided with the intake / exhaust hole. However, the space is formed by fixing the side panels on both sides of the center panel, and the diaphragm is sandwiched between the center panel and both side panels. Therefore, a pump chamber having a sufficient space can be formed by the diameter and thickness of the center panel and the side panel, and the diaphragm can displace the entire space. A sufficient flow rate of the liquid can be discharged with each drive.

Further, in the double pump of the present invention, the pump main body is fixed in an upright position in the radial direction, and the exhaust hole is formed vertically at a ground surface with an opening at the top. It is characterized in that it is. Therefore, even if the gas dissolved in the liquid foams in the pump chamber, the bubbles are reliably discharged from the exhaust hole.

In the double pump according to the present invention, an indicator provided for measuring displacement of each of the diaphragms due to pressurization of a working fluid is provided on the diaphragm by penetrating a pump body toward the pressurizing chamber. And a sensor for detecting the position of the rod. Therefore, by confirming at least a state in which the pump chamber is filled with liquid and an empty state by the detection signal from the sensor, it is possible to alternately control the driving of the two pumps.

[0011]

Next, an embodiment of a double pump according to the present invention will be described with reference to the drawings. FIG. 1 is a sectional view showing a double pump according to the present embodiment, and FIG. 2 is a side view. The double pump 1 has a circular shape as shown in FIG. 2, and is fixed by a metal fitting 2 in an upright state. And, inside, two pumps are configured as shown in FIG.
The double pump 1 has a central board 3 sandwiched between side boards 11 and 21 and is integrally fixed on both sides by bolts on the circumference. In the body constituted by the fixed center board 3 and the side boards 11 and 21, spaces 12 and 22 each having a rhombic cross section are provided between the center board 3 and the side board 4 and between the center board 3 and the side board 5. Are formed. The first pump 10 is configured on the space 12 side, and the second pump 20 is configured on the space 22 side.

Further, diaphragms 13 and 23 are provided between the center board 3 and the side board 4 and between the center board 3 and the side board 5 and fixed circumferentially.
2 is divided into two rooms. This diaphragm 13, 2
Numeral 3 is shaped to be attached to both surfaces of the center panel 3 and the side panels 11 and 21 and has such elasticity that it can be deformed. The diaphragms 13 and 23 which can be deformed in this manner are moved by the springs 14 and 24 to the central board 3.
Is biased to the side. Springs 14 and 24 are spring supports 15 and 25 fixed at the center of the diaphragms 13 and 23.
And plugs 16 and 26 fitted and fixed in through holes at the centers of the side panels 11 and 21.

The stoppers 16 and 26 are provided with the diaphragm 1.
A through hole is formed at a position overlapping the center of each of the rods 3 and 23, and rods 17 and 27 fixed to spring receivers 15 and 25 are inserted. The rods 17, 27 are connected to the diaphragm 13,
23 shows the displacement of the photosensors 18a, 18b, 28a, and 2 fixed outside the side panels 11, 21.
8b, the position is measured. The photo sensors 18a, 18b, 28a, 28b
Holder 19 having a groove in which rods 17 and 27 can slide,
29 (see FIG. 2) and its rods 17, 2
7 are detected at two points each.

By the way, the spaces 12 and 22 partitioned by the diaphragms 13 and 23 constitute a pump chamber in which a liquid such as a chemical solution is supplied on the inner side facing the central panel 3, and the side panel 1
A pressurizing chamber configured to supply inert gas as a working fluid is formed on the outside facing 1, 21. Therefore, in the center panel 3, the input flow path 31 and the output flow path 32 communicating with the pump chamber of the first pump 10 and the input flow path communicating with the pump chamber of the second pump 20 are provided at positions indicated by broken lines in FIG. 36 and output channel 3
7 are drilled. Also, for the central board 3. As shown in FIG. 1, exhaust holes 33 and 38 for removing air bubbles in the vertical direction are provided.
It is formed so as to communicate with each pump chamber.

On the other hand, the side panels 11 and 21 have suction and exhaust holes 34 for sucking and discharging nitrogen gas as a working fluid to and from the pressurizing chamber of the first pump 10, and similarly to the pressurizing chamber of the second pump 20. A suction / exhaust hole 39 for sucking / exhausting nitrogen gas is drilled. The input channels 31 and 36 are connected to the chemical tank, the output channels 32 and 37 are connected to the clean room, and the intake / exhaust holes 3 are provided through the valves in the respective channels as in the conventional example.
4 and 39 are piped to a gas supply source and exhaust holes 33 and 38 are provided.
Has been released to the atmosphere.

Therefore, in the double pump 1 having such a configuration, the chemical is sent to the apparatus side as follows. The double pump 1 shown in FIG. 1 is in a state after the first pump 10 has discharged the chemical solution, and the diaphragm 13 is in contact with the central panel 3. At this time, the pressurizing chamber expands, and the inside thereof is filled with nitrogen gas to pressurize the diaphragm 13.
On the other hand, the second pump 20 is in a state where the nitrogen gas in the pressurized chamber is exhausted and the pump chamber is filled with a chemical solution instead (the fluid is omitted in the drawing). Therefore, diaphragm 2
3 is in contact with the side panel 21. First, the first pump 10 is filled with a chemical solution in an inner pump chamber in a state like a second pump 20 shown in FIG.
Nitrogen gas is supplied through 4 and the diaphragm 13 is pressurized. As a result, the diaphragm 13 is displaced to the right in the drawing, and the chemical liquid filled in the pump chamber is pressurized, flushed to the output flow path 32, and sent to a processing device in a clean room.

Such displacement of the diaphragm 13 is confirmed by the position of the rod 17, and is detected by the photo sensor 18a when the diaphragm 13 comes into contact with the central panel 3 and discharge of the chemical solution is completed as shown in the figure. Then, based on the detection signal, the valve provided in the intake / exhaust hole and the valve provided in the output flow path 32 are closed. Thus, the discharge of the chemical solution by the first pump 10 ends. Then, while the empty first pump 10 is being filled with the chemical solution, the second pump 20 discharges the chemical solution. That is, as shown in FIG. 1, when the first pump 10 becomes empty, the pump chamber of the second pump 20 is filled with the drug solution. The filling of the chemical is detected by the photo sensor 28b, and when a state of being sufficiently filled is confirmed,
After the first pump 10, the second pump 20 discharges the chemical solution.

In the case of the second pump 20, the chemical solution is discharged in the same manner. That is, the nitrogen gas is supplied from the suction / exhaust hole 39, and the diaphragm 23 is pressurized and displaced. As a result, the chemical liquid filled in the pump chamber is pressurized and flushed from the output flow path 37. During this time, in the first pump 10, the valve provided in the input flow path 31 is opened to communicate with the chemical solution supply source, while the valve provided in the intake / exhaust hole 34 is switched to release the pressurized chamber to the atmosphere. Therefore, the chemical is supplied to the pump chamber of the first pump 10, and the spring 14 is bent by the pressure of the flowing chemical. Then, when the diaphragm 13 is displaced and comes into contact with the side panel 11, the photo sensor 18b detects the rod 17, the valve is closed based on the detection signal, and the filling of the chemical solution is completed.

On the other hand, the chemical solution is discharged from the second pump 20, and the photo sensor 28a detects the rod 27 when the diaphragm 23 contacts the central panel 3. Then, each valve is closed based on the detection signal, and the supply of the nitrogen gas and the discharge of the chemical solution are stopped. Thereafter, the chemical is discharged from the first pump 10 again, and the chemical is supplied to the second pump 20.

The double pump 1 according to the present embodiment as described above
In this case, the chemical solution and the nitrogen gas which is a working fluid for discharging the chemical solution are isolated by the diaphragms 13 and 23, so that the nitrogen gas does not dissolve in the chemical solution. As a result, the gas in the chemical solution does not become bubbles and cause a problem in the product. Further, the gas foamed in the pump is exhausted from the exhaust holes 33 and 38 and does not flow out to the processing apparatus together with the chemical. Further, since the gas supply line is isolated from the chemical solution by the diaphragms 13 and 23, the chemical solution does not diffuse back into the gas line, so it is necessary to use expensive piping such as stainless steel or Teflon having corrosion resistance. And the cost can be reduced.

Further, the first pump 10 and the second pump 20
By integrally providing two pumps consisting of In particular, since the diaphragm is used as a separating member for separating the inert gas from the chemical solution without using a bellows, a sufficient discharge amount can be obtained at one time, and the pump itself is small because the driving amount is small. It was compact. Since the double pump 1 having a disc shape is configured to be used upright, the installation area can be reduced.

It should be noted that the present invention is not limited to the above-described embodiment, and various changes can be made without departing from the gist of the present invention. For example, in the above embodiment, the photo sensors 18a, 18b, 28a, 28b for detecting the positions of the rods 17, 27 are used as indicators, but a potentiometer may be used.

[0023]

According to the present invention, a pair of spaces provided in the pump main body are separated into two chambers by diaphragms, respectively. The pump main body has two pump chambers located inside both diaphragms. An input flow path for inputting a liquid, an output flow path for outputting a liquid, an exhaust hole for discharging bubbles in the liquid, and communication with each of the pressurizing chambers located outside both diaphragms. By adopting a configuration in which a suction and exhaust hole for supplying a working fluid is provided, it is possible to provide a double pump in which a liquid and a working fluid for pressurizing the liquid are separated.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of a double pump according to the present invention.

FIG. 2 is a side view showing an embodiment of the double pump according to the present invention.

FIG. 3 is a block diagram showing a conventional chemical liquid pressure feeding means.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Double pump 3 Central board 11,21 Side board 12,22 Space 13,23 Diaphragm 17,27 Rod 18a, 18b, 28a, 28b Photo sensor 31,36 Input flow path 32,37 Output flow path 33,38 Exhaust hole 34 , 39 intake and exhaust holes

Claims (4)

[Claims] A pair of spaces provided adjacent to a pump body are each separated into two chambers by a diaphragm, and the pump body communicates with each pump chamber located inside both diaphragms by a liquid. An input flow path for inputting a liquid, an output flow path for outputting a liquid, an exhaust hole for discharging bubbles in the liquid, and a working fluid that communicates with each of the pressurizing chambers located outside both diaphragms. A double pump having a suction and exhaust hole for supplying air. 2. The double pump according to claim 1, wherein the pump main body includes a central panel in which the input channel, the output channel, and the exhaust hole are formed, and a pair of the central panel in which the intake and exhaust holes are formed. The side panel is formed by fixing the side panel on both sides of the central panel to form the space, and the diaphragm is sandwiched between the central panel and both side panels. And double pump. 3. The double pump according to claim 2, wherein the pump body is fixed upright in a radial direction, and the exhaust hole has an opening at a top and is perpendicular to a ground plane. A double pump characterized by being drilled in a pump. 4. The double pump according to claim 1, wherein an indicator provided for measuring displacement of each of the diaphragms due to pressurization of a working fluid is provided on a side of the pressurizing chamber. A double pump comprising a rod penetrating through the main body and vertically suspended from the diaphragm, and a sensor for detecting a position of the rod.