JP2010043607A - Diaphragm pump and pump device having the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide, by a simple configuration, a diaphragm pump capable of sucking and discharging liquid utilizing two forces acting on a diaphragm from both surface sides thereof in reverse directions, and a pump device having the diaphragm pump. <P>SOLUTION: A coil spring 70 is coaxially fitted to the center shaft 62 of a rod 60 in the large diameter hole 33b of the through-hole 33 of a housing H, and locked between a boundary stage 33 between the large diameter hole 33b and the small diameter hole 33a thereof and the annular flange 62a of the center shaft 62. A supply hole 44 for supplying an air flow from an air flow supply source into a pressing chamber R1 is formed in a lower housing member 40. Since the biasing force of the coil spring 70 acts on a main diaphragm 90 via the base end side shaft 63 of the rod 60 from the pump chamber R2 side, the pressure of the air flow into the pressing chamber R2 acts on the main diaphragm 90 from the pressing chamber R1 side. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a diaphragm pump employed for inhaling and discharging a liquid in a semiconductor manufacturing apparatus, a liquid crystal panel manufacturing apparatus, a drug manufacturing apparatus, and other various apparatuses, and a pump apparatus including the diaphragm pump.

  Conventionally, as this type of pump device, a chemical solution supply system described in Patent Document 1 below has been proposed. This chemical supply system includes a pump unit, and the pump unit forms a pump chamber and a working chamber by dividing the space by a diaphragm in a space between the pump housing and the valve housing. Here, the pump chamber is located closer to the pump housing than the diaphragm, while the working chamber is located closer to the valve housing than the diaphragm.

In the pump unit configured as described above, when the chemical solution is sucked into the pump chamber, the diaphragm is displaced toward the working chamber side by decompression of the working chamber. Further, when discharging the sucked chemical into the pump chamber, the diaphragm is displaced to the pump chamber side by pressurizing the working chamber.
JP 2005-240762 A

  By the way, in the above pump unit, when the inside of the working chamber is pressurized and the inside of the pressurized working chamber is decompressed, an intake passage for supplying compressed air from an air source into the working chamber and the inside of the working chamber. And an exhaust path for exhausting by evacuation by a vacuum source is formed inside the wall portion of the valve housing.

  In other words, the pump unit employs both functions of pressurization into the working chamber and decompression of the working chamber, so that pressurization and decompression act only on the surface of the diaphragm on the working chamber side. It has become. For this reason, the intake passage and the exhaust passage described above are not formed separately in the wall portions of the valve housing and the pump housing, but are necessarily formed in the wall portions of the same valve housing. Has been. This means that the internal structure of the valve housing is complicated. As a result, the problem that the structure of a pump unit becomes complicated is caused.

  Therefore, in order to deal with the above-described problems, the present invention utilizes two forces that act on the diaphragm in opposite directions from both sides thereof to suck and discharge liquid with a simple configuration. It is an object of the present invention to provide a diaphragm pump and a pump device including the diaphragm pump.

In solving the above-described problems, the diaphragm pump according to the present invention, according to the description of claim 1,
A housing (H);
A main diaphragm (90) provided in the housing and dividing the interior of the housing into a pressing chamber (R1) and a pump chamber (R2);
Provided between the pump chamber and a recess (33b) formed in a concave shape so as to open in the pump chamber in the coaxial wall portion (31, 32) coaxially facing the main diaphragm via the pump chamber in the housing. A sub-diaphragm (100) for liquid-tightly partitioning the recess from the pump chamber;
Urging means (70) for urging the sub diaphragm to the pump chamber side from the inside of the concave portion of the housing,
The sub-diaphragm is coaxially connected from the pump chamber to the central part (91) of the main diaphragm at the central part (101), and has a smaller outer diameter than the main diaphragm,
A supply hole (44) for supplying an air flow from the air flow supply source (80) into the press chamber is formed in a peripheral wall portion of the press chamber in the housing,
A suction part (50b, 54a) for sucking the liquid from the liquid supply source (10) into the pump chamber and a discharge part (54b, 50c) for discharging the liquid in the pump chamber are provided on the peripheral wall portion of the pump chamber in the housing. Is formed.

  According to this, in a state where the suction of the liquid into the pump chamber is completed, the sub-diaphragm moves the main diaphragm to the pressing chamber side under the urging force by the urging means in a state where the supply of air flow into the pressing chamber is stopped In this state, the volume of the pump chamber is increased.

  In such a state, when an air flow is supplied into the pressing chamber through the supply hole, the main diaphragm is energized so as to reduce the volume of the pump chamber under the pressure of the air flow into the pressing chamber. Displaces against the biasing force of the means. Along with this, the liquid in the pump chamber is discharged from the discharge section.

  Thereafter, when the supply of the air flow into the pressing chamber is stopped, the main diaphragm is urged and displaced by the urging means via the sub diaphragm so as to increase the volume of the pump chamber, and the liquid is pumped in the pump chamber. Inhaled through the inhalation part.

  Here, the urging force of the urging means acts on the main diaphragm from the pump chamber side via the sub-diaphragm. On the other hand, when the pressure of the air flow discharges the liquid in the pump chamber as described above, the pressing chamber Acts on the main diaphragm from the side. This means that when the liquid in the pump chamber is discharged, the biasing force through the sub diaphragm and the pressure of the air flow in the pressing chamber act on the main diaphragm so as to face each other through the same main diaphragm. Means.

  In other words, a recess for energizing by the energizing means and a supply hole for supplying an air flow into the pressing chamber are separately provided on both sides of the main diaphragm with respect to the housing, so that both sides of the main diaphragm are provided. Thus, the structure of the housing can be simplified by effectively utilizing both the urging force by the urging means acting in the opposite direction and the pressure by the air flow.

  In addition, if the sub diaphragm has an outer diameter smaller than that of the main diaphragm to such an extent that the displacement of the sub diaphragm does not affect the change in the volume of the pump chamber due to the main diaphragm, suction of liquid into the pump chamber and The discharge of the liquid from the pump chamber can be ensured satisfactorily.

  Further, as described above, since the pump chamber is liquid-tightly sealed from the recess by the sub diaphragm, foreign matter such as dust does not enter the pump chamber from the recess. This is particularly noticeable when a means for supplying air flow through the peripheral wall portion of the pump chamber in the housing as the urging means is adopted, and for example, the diaphragm pump is used. It is effective when applied to a semiconductor manufacturing apparatus that strictly requires the cleanliness of a chemical solution as a liquid.

According to the description of claim 2, the present invention provides the diaphragm pump according to claim 1,
The biasing means is a coil spring (70) provided in the recess of the housing and biasing the sub diaphragm toward the pump chamber.

  According to this, the biasing force of the coil spring acts appropriately toward the main diaphragm via the sub diaphragm. For this reason, when the liquid in the pump chamber is discharged, the biasing force of the coil spring acts correctly on the main diaphragm in the direction opposite to the pressure of the air flow into the pressing chamber. As a result, the operational effect of the invention of claim 1 can be achieved more appropriately.

Moreover, according to the description of claim 3, the pump device provided with the diaphragm pump according to the present invention,
The diaphragm pump (P) according to claim 1 or 2,
Upstream valve means (110, 114) that opens when the liquid flows into the pump chamber of the diaphragm pump from the suction portion and closes when the liquid stops flowing;
Downstream valve means that opens when supplying the liquid discharged from the pump chamber through the discharge section to the supplied system (20) and closes when supplying the liquid to the supplied system is stopped ( 120, 123).

  According to this, the suction of the liquid into the pump chamber and the stop thereof are performed by opening and closing the upstream valve means, and the discharge and the stop of the liquid from the pump chamber are performed by opening and closing the downstream valve means. This is done by closing the valve. For this reason, the suction and discharge of the liquid by the diaphragm pump can be performed more accurately. As a result, the operational effect of the invention according to claim 1 or 2 can be further improved.

  According to a fourth aspect of the present invention, in the pump device comprising the diaphragm pump according to the third aspect, the supply flow rate of liquid from the downstream valve means to the supply system is kept at a constant minute flow rate. It is characterized by comprising orifice means (124, 130) for restricting.

  According to this, the liquid discharged from the pump chamber through the discharge portion at the time of discharge of the diaphragm pump is squeezed by the orifice means and supplied to the supply system at a constant minute flow rate. As a result, the operation and effect of the invention according to claim 3 can be achieved while the processing in the supply system, for example, the processing of the semiconductor wafer in the processing cup of the semiconductor manufacturing apparatus is performed satisfactorily.

According to a fifth aspect of the present invention, in the pump device including the diaphragm pump according to the third or fourth aspect,
A rod (60) extending coaxially from the center of the sub-diaphragm to the opposite side of the main diaphragm into the recess, a position detection means (140), a first control means (212, 213, 214) and a first 2 control means (202, 203, 241),
The recess of the housing is opened coaxially with the sub-diaphragm at the bottom (33a) and communicates with the inside of the recess and communicates with the outside of the bottom.
The rod has a distal end side shaft portion (61) that is slidably fitted in the bottom portion so as to be able to extend from the bottom portion through the concave portion,
The position detecting means is provided at or near the bottom of the recess, and when the diaphragm pump completes the suction of the liquid into the pump chamber, the sliding position of the tip side shaft portion of the rod is determined by the first sliding of the rod. Detecting the moving position, and when the diaphragm pump completes the discharge of the liquid in the pump chamber, the sliding position of the tip shaft portion of the rod is detected as the second sliding position of the rod,
When the position detecting means detects the second sliding position of the rod, the first control means stops the supply of the air flow into the pressing chamber in order to suck the liquid into the pump chamber, and the upstream side valve The air flow source, the upstream valve means and the downstream valve means are controlled to open the means and close the downstream valve means,
The second control means supplies the air flow into the pressing chamber in order to discharge the liquid in the pump chamber when the post-control position detection means by the first control means detects the first sliding position of the rod. And the air flow supply source, the upstream valve means and the downstream valve means are controlled so as to close the upstream valve means and open the downstream valve means. To do.

  According to this, when the position detecting means detects the second sliding position of the rod, the supply of the air flow into the pressing chamber is stopped to suck the liquid into the pump chamber, and the upstream valve means The valve is opened and the downstream valve means is closed. Thereafter, when the position detecting means detects the first sliding position of the rod, supply of the air flow into the pressing chamber is started to discharge the liquid in the pump chamber, and the upstream valve means is closed. And the downstream valve means is opened.

  As a result, the operation and effect of the third or fourth aspect can be achieved while the diaphragm pump is well controlled so as to alternately suck and discharge the liquid.

  According to a sixth aspect of the present invention, there is provided a pump device comprising the diaphragm pump according to the fifth aspect, wherein the discharge of the liquid in the pump chamber accompanying the control of the second control means is a predetermined abnormal time (To When the operation is not completed before elapse of), the operation of the diaphragm pump is prohibited.

  Thus, the action and effect of the invention according to claim 5 can be achieved while taking countermeasures for the abnormality of the diaphragm pump in a timely manner.

Moreover, according to the description of claim 7, the diaphragm pump according to the present invention,
A housing (H);
A main diaphragm (90) provided in the housing and dividing the interior of the housing into a pressing chamber (R1) and a pump chamber (R2);
Provided between the pump chamber and the recess (33b) formed in a concave shape so as to open into the pump chamber in the coaxial wall portion (31, 32) concentrically facing the main diaphragm via the pump chamber in the housing. A sub-diaphragm (100) that liquid-tightly partitions the recess from the pump chamber;
An urging means (70a) provided in the pressing chamber for urging the main diaphragm to be pressed toward the pump chamber;
The sub-diaphragm is coaxially connected from the pump chamber to the central part (91) of the main diaphragm at the central part (101), and has a smaller outer diameter than the main diaphragm,
A suction wall (50b, 54a) for sucking liquid from the liquid supply source (10) into the pump chamber, a discharge section (54b, 50c) for discharging the liquid in the pump chamber, and a peripheral wall portion of the pump chamber in the housing A supply hole (34) for supplying an air flow from the air flow supply source (80) into the recess is formed.

  According to this, in a state where the liquid has been sucked into the pump chamber, the main diaphragm resists the urging means under the pressure of the air flow supplied into the recess through the supply hole. The pump chamber is displaced to increase the volume of the pump chamber.

  In such a state, when the supply of the air flow into the recess is stopped, the main diaphragm receives the urging force of the urging means from the pressing chamber and is displaced so as to reduce the volume of the pump chamber. . Along with this, the liquid in the pump chamber is discharged from the discharge section.

  Thereafter, when the air flow is supplied into the recess through the supply hole, the main diaphragm is displaced against the biasing means so as to increase the volume of the pump chamber under the pressure of the air flow. Then, the liquid is sucked into the pump chamber through the suction portion.

  Here, the urging force of the urging means acts on the main diaphragm from the pressing chamber side, while the pressure of the air flow resists the urging means when discharging the liquid in the pump chamber as described above. It acts on the main diaphragm from the pump chamber side via the auxiliary diaphragm. This means that when the liquid in the pump chamber is discharged, the biasing force and the pressure of the air flow act toward the main diaphragm so as to face each other through the same main diaphragm.

  In other words, by providing the pressing chamber for urging by the urging means and the supply hole for supplying the air flow into the recess separately on the both sides of the main diaphragm, the main diaphragm is provided. The structure of the housing can be simplified by effectively utilizing both the urging force by the urging means acting in the opposite direction from the both surface sides and the pressure by the air flow.

  In addition, if the sub diaphragm has an outer diameter smaller than that of the main diaphragm to such an extent that the displacement of the sub diaphragm does not affect the change in the volume of the pump chamber due to the main diaphragm, suction of liquid into the pump chamber and The discharge of the liquid from the pump chamber can be ensured satisfactorily.

  Further, as described above, since the pump chamber is liquid-tightly sealed from the recess by the sub diaphragm, foreign matter such as dust does not enter the pump chamber from the recess. This is particularly noticeable when a means for supplying air flow through the peripheral wall portion of the pump chamber in the housing as the urging means is adopted, and for example, the diaphragm pump is used. It is effective when applied to a semiconductor manufacturing apparatus that strictly requires the cleanliness of a chemical solution as a liquid.

Moreover, according to the description of Claim 8, the pump device provided with the diaphragm pump according to the present invention,
The diaphragm pump (Pa) according to claim 7, wherein the diaphragm pump (Pa) has a rod (60) that extends coaxially from the center portion (91) of the sub-diaphragm toward the opposite side of the main diaphragm into the recess. Upstream valve means (110, 114), downstream valve means (120, 123) and orifice means (124, 130), position detection means (140), first control means (212, 213, 214) and second Control means (202, 203, 241),
The recess of the housing is opened coaxially with the sub-diaphragm at the bottom (33a) and communicates with the inside of the recess and communicates with the outside of the bottom.
The rod has a distal end side shaft portion (61) that is slidably fitted in the bottom portion so as to be able to extend from the bottom portion through the concave portion,
The upstream valve means opens when the liquid flows into the pump chamber of the diaphragm pump from the suction portion, and closes when stopping the flow of the liquid,
The downstream valve means opens when supplying the liquid discharged from the pump chamber through the discharge section to the supplied system (20), and closes when supplying the liquid to the supplied system is stopped. To speak,
The orifice means is adapted to restrict the supply flow rate of the liquid from the downstream valve means to the supply system to a constant minute flow rate.
The position detecting means is provided at or near the bottom of the recess, and when the diaphragm pump completes the suction of the liquid into the pump chamber, the sliding position of the tip side shaft portion of the rod is determined by the first sliding of the rod. Detecting the moving position, and when the diaphragm pump completes the discharge of the liquid in the pump chamber, the sliding position of the tip shaft portion of the rod is detected as the second sliding position of the rod,
When the position detecting means detects the second sliding position of the rod, the first control means supplies the air flow into the recess and sucks the upstream valve means to suck the liquid into the pump chamber. The air flow supply source, the upstream valve means and the downstream valve means are controlled to open and close the flow valve means,
When the post-control position detecting means by the first control means detects the first sliding position of the rod, the second control means is configured to discharge the liquid in the pump chamber to discharge the air flow into the recess. The air flow supply source, the upstream valve means, and the downstream valve means are controlled so that the supply is stopped, the upstream valve means is closed, and the downstream valve means is opened.

  According to this, when the position detecting means detects the second sliding position of the rod, in order to suck the liquid into the pump chamber, an air flow is supplied into the recess and the upstream valve means is opened. And the downstream valve means closes. Thereafter, when the position detecting means detects the first sliding position of the rod, in order to discharge the liquid in the pump chamber, the supply of air flow into the recess is stopped and the upstream valve means is closed. And the downstream valve means is opened. Therefore, the diaphragm pump can be well controlled so as to alternately suck and discharge the liquid.

  Also, under such good control, the liquid discharged from the pump chamber through the discharge section during the discharge of the diaphragm pump is throttled by the orifice means to be supplied to the supply system at a constant minute flow rate. Is done.

  As a result, the operation and effect of the invention according to claim 7 can be achieved while the processing in the supplied system, for example, the processing of the semiconductor wafer in the processing cup of the semiconductor manufacturing apparatus is satisfactorily performed.

  In addition, the code | symbol in the bracket | parenthesis of each said means shows the correspondence with the specific means as described in embodiment mentioned later.

Hereinafter, each embodiment of the present invention will be described with reference to the drawings.
(First embodiment)
FIG. 1 shows a first embodiment of a diaphragm pump according to the present invention applied to a single wafer processing system of a semiconductor manufacturing apparatus and a pump apparatus provided with the diaphragm pump. The pump apparatus includes a chemical tank 10. And the processing cup 20. The chemical tank 10 stores a chemical solution. In addition, a semiconductor wafer W is placed on the spin table 21 in the processing cup 20.

  The pump device includes a diaphragm pump P as shown in FIGS. As shown in FIG. 2, the diaphragm pump P has a pump housing H. The pump housing H has a cylindrical trapezoidal shape by assembling an inner housing member 50 between upper and lower housing members 30 and 40. It is configured.

  The upper housing member 30 is formed of a fluororesin so as to integrally have a cylindrical trapezoidal large-diameter wall portion 31 and a small-diameter wall portion 32 that protrudes downward from the central portion of the lower surface of the large-diameter wall portion 31. Has been. The upper housing member 30 has a through-hole portion 33 into which a rod 60 and a coil spring 70 (described later) are fitted.

  The through-hole portion 33 is formed so as to penetrate the large-diameter wall portion 31 and the small-diameter wall portion 32 coaxially, and the through-hole portion 33 has a small-diameter hole portion 33a and a large-diameter hole portion 33b. ing. The small-diameter hole portion 33a is formed coaxially in the central upper portion of the large-diameter wall portion 31, and the small-diameter hole portion 33a opens upward from the large-diameter wall portion 31 at its upper end opening. . The large-diameter hole portion 33b is coaxially formed so as to communicate with the small-diameter hole portion 33a from the portion of the central portion of the large-diameter wall portion 31 excluding the central upper portion to the small-diameter wall portion 32. The hole 33b communicates with a pump chamber R2 (described later) at its lower end opening.

  The lower housing member 40 is formed of a fluororesin in a cylindrical trapezoidal shape, and a central recess 41 and an annular groove 42 are formed in the lower housing member 40 as described later. The central recess 41 is formed in a central portion of the upper surface of the lower housing member 40 so as to be concave with a substantially semi-elliptical vertical cross section, and an outer peripheral portion 41 a of the central recess 41 is formed on the lower housing member 40. It protrudes in an annular shape upward from the upper surface 41b. The annular groove 42 is formed in a concave shape downward from the upper surface 41b of the lower housing member 40 along the outer peripheral portion 41a of the central recess 41, and an O-ring 43 is fitted into the annular groove 42. ing.

  The lower housing member 40 has a supply hole 44, and the supply hole 44 opens from the bottom surface into the central recess 41 at the inner end thereof. Further, the outer end portion of the supply hole 44 communicates from a part of the outer peripheral surface of the lower housing member 40 into the air flow supply source 80 (see FIG. 1) via a pipe 81 (see FIG. 1). . Thereby, the air flow supply source 80 supplies the air flow by pressure feeding through the piping 81 and the supply hole 44 into the central recess 41 at a constant pressure under the control of the controller 150 (described later).

  The middle housing member 50 is made of polytetrafluoroethylene (hereinafter referred to as PTFE) so as to integrally have a cylindrical trapezoidal wall portion 50a and cylindrical upstream and downstream boss portions 50b and 50c. . The wall 50a has a central recess 51. The central recess 51 faces the lower surface of the central portion of the wall 50a so that the central recess 41 and the annular groove 42 of the lower housing member 40 face coaxially. It is formed in a substantially U-shaped cross section from the side.

  The central recess 51 has a bottom side small diameter part 51a and an opening side large diameter part 51b. The through hole 33 of the upper housing member 30 communicates with the center of the bottom surface of the bottom side small diameter portion 51a, and the opening side large diameter portion 51b is connected to the bottom side small diameter portion 51a directly below the bottom side small diameter portion 51a. It is formed so as to communicate coaxially.

  Here, the inner diameter of the bottom side small diameter part 51 a is the same as the opening end side inner diameter of the outer peripheral part 41 a of the central recess 41. Further, the opening-side large diameter portion 51 b of the central recess 51 has the same inner diameter as the diameter of the outer inner peripheral surface of the annular groove portion 42 of the lower housing member 40. For this reason, the annular step portion 51c formed at the boundary between the opening-side large-diameter portion 51b and the bottom-side small-diameter portion 51a faces the annular groove portion 42 from the opening side on its lower surface. The axial length of the opening-side large-diameter portion 51b is set to be longer than the length of the portion of the outer peripheral portion 41a of the central recess 41 that protrudes upward from the upper surface of the lower housing member 40.

  The wall portion 50a has a central through hole portion 52. The central through hole portion 52 has a circular cross section so as to correspond coaxially to the small diameter wall portion 32 of the upper housing member 30. The wall 50a is formed in a penetrating manner in the upper wall portion of the central recess 51.

  Further, the wall portion 50a has an annular L-shaped portion 53, and the annular L-shaped portion 53 is formed so as to project integrally from the lower end portion of the inner peripheral surface of the central through hole portion 52 toward the axial center side. Has been. The annular L-shaped portion 53 has both annular wall portions 53a and 53b, and the annular wall portion 53a protrudes from the lower end portion of the inner peripheral surface of the central through hole portion 52 toward the axial center along the radial direction. Yes. The annular wall portion 53b extends upward from the radially projecting end portion of the annular wall portion 53a so as to be parallel to the axial portion of the inner peripheral surface of the central through hole portion 52.

  The middle housing member 50 configured as described above is assembled between the upper and lower housing members 30 and 40 as follows. That is, the middle housing member 50 is airtightly mounted on the outer peripheral portion of the upper surface 41 b of the lower housing member 40 at the outer peripheral portion of the lower surface. In this case, in the opening-side large-diameter portion 51 b of the central recess 51 of the middle housing member 50, the annular step portion 51 c passes through the outer peripheral portion 93 (described later) of the main diaphragm 90, and the central recess of the lower housing member 40. 41 is seated on the outer periphery 41a. Along with this, the O-ring 43 is pressed into the annular groove 42 of the lower housing member 40 by the outer peripheral portion 93 of the main diaphragm 90, and the central recesses 41 of both the lower and middle housing members 40, 50, 51 is hermetically sealed from each interface between the lower and middle housing members 40, 50.

  The upper housing member 30 is mounted on the upper surface of the middle housing member 50 at its lower surface. Here, the small-diameter wall portion 32 of the upper housing member 30 is coaxially fitted into the central through hole portion 52 from the upper surface of the middle housing member 50. Accordingly, the small-diameter wall portion 32 is seated on the annular wall portion 53b of the annular L-shaped portion 53 via the outer peripheral portion 103 (described later) of the sub diaphragm 100 at the lower end surface.

  As shown in FIG. 2, the upstream / downstream boss portions 50 b and 50 c integrally extend in opposite directions along the radial direction from both opposing portions of the outer peripheral surface of the middle housing member 50. The upstream boss portion 50 b communicates with the bottom small diameter portion 51 a of the central recess 51 through the suction hole portion 54 a formed in the middle housing member 50 at the inner end opening. On the other hand, the downstream boss portion 50c passes through the discharge hole portion 54b formed in the inner housing member 50 so as to face the suction hole portion 54a at the inner end opening portion thereof, and passes through the bottom small diameter portion of the central recess 51. It communicates with 51a.

  The diaphragm pump P includes the rod 60, the coil spring 70, the main diaphragm 90, and the sub diaphragm 100 described above. The rod 60 is fitted into the through-hole portion 33 of the upper housing member 30 from the distal end opening portion 33c, and the rod 60 includes the distal end side shaft portion 61, the middle side shaft portion 62, and the proximal end side shaft portion 63. Therefore, it is formed coaxially with a fluororesin.

  Thus, in the rod 60, the distal end side shaft portion 61 is slidably fitted into the small diameter hole portion 33a so as to protrude upward from the small diameter hole portion 33a of the through hole portion 33. In the present embodiment, the fitting intersection of the small diameter hole portion 33a with the distal end side shaft portion 61 and the axial length of the small diameter hole portion 33a can prevent lateral deflection in the small diameter hole portion 33a of the distal end side shaft portion 61. Each is selected appropriately. Further, the middle shaft portion 62 has a larger outer diameter than the front end side shaft portion 61, and the middle shaft portion 62 is coaxially fitted in the large diameter hole portion 33 b of the through hole portion 33. Has been. In addition, an annular flange 62a is formed on the lower end portion of the middle shaft portion 62 so as to project radially in an annular shape. Note that the outer diameter of the annular flange 62a is smaller than the inner diameter of the large-diameter hole 33b.

  Further, the base end side shaft portion 63 of the rod 60 protrudes into the central recess 51 of the middle housing member 50, and a male screw portion 63 a is coaxially formed on the outer peripheral portion of the base end side shaft portion 63. ing. As shown in FIG. 2, the tip opening 33c of the above-described through-hole 33 is coaxially and annularly raised toward the annular L-shaped portion 53, and the tip opening 33c The protruding side outer peripheral surface is formed in a curved surface shape that is convex downward in the cross section.

  The coil spring 70 is coaxially fitted to the middle shaft portion 62 of the rod 60 in the large-diameter hole portion 33b of the through-hole portion 33, and the coil spring 70 is large at both ends thereof. It is engaged with the boundary step portion 33 d between the diameter hole portion 33 b and the small diameter hole portion 33 a and the annular flange portion 62 a of the middle shaft portion 62. Thus, the coil spring 70 urges the rod 60 coaxially toward the central recess 51 of the inner housing member 50. Note that the upward sliding of the rod 60 is restricted by contact with the boundary step portion 33 d of the middle shaft portion 62.

  Both the main diaphragm 90 and the sub-diaphragm 100 are formed in a circular shape with PTFE. The main diaphragm 90 includes a central shaft portion 91, an intermediate film portion 92, and an outer peripheral portion 93. The central shaft portion 91 has a female screw hole portion 91a, and this female screw hole portion 91a is coaxially formed in the central shaft portion 91 from its upper end surface. The intermediate film portion 92 has a thick portion 92a and a thin portion 92b, and the thick portion 92a extends integrally outward from the lower portion of the central shaft portion 91 so as to form an annular shape. . The thin portion 92b is formed to be thinner than the thick portion 92a so as to have sufficient flexibility. The thin portion 92b is outward from the thick portion 92a so as to form an annular shape. It extends integrally. The outer peripheral portion 93 integrally extends outward from the thin portion 92b so as to be thick and annular.

  In the main diaphragm 90 configured as described above, when the middle housing member 50 is mounted on the outer circumferential portion of the upper surface 41b of the lower housing member 40 at the lower circumferential portion thereof as described above, the outer circumferential portion 93 is centered. The outer peripheral portion 41a of the central recess 41 of the lower housing member 40 and the shaft portion 91 and the intermediate film portion 92 are opposed to the central recess 41 of the lower housing member 40 from the opening surface side on each lower surface thereof. It is placed on the O-ring 43.

  After that, the inner housing member 50 is fitted with the outer peripheral portion 93 together with the upper portion of the O-ring 43 in the opening 51b of the central recess 51 of the inner housing member 50 at the outer peripheral portion of the lower surface. The lower housing member 40 is attached to the outer peripheral portion of the upper surface 41b. At this time, the O-ring 43 is pressed into the annular groove portion 42 of the lower housing member 40 as described above. In this way, the main diaphragm 90 is assembled to the lower housing member 40 and the middle housing member 50, and the central recess portion 41 and the central recess portion 51 are pressed into the pressing chamber R1 and the pump by the central shaft portion 91 and the intermediate film portion 92. A compartment is formed in the chamber R2. The displacement of the main diaphragm 90 toward the pressing chamber R1 is restricted by the contact of the central shaft portion 91 with the cylindrical pedestal portion 41c protruding from the central portion of the bottom surface of the central recess 41.

  The sub diaphragm 100 includes a central shaft portion 101, an intermediate film portion 102, and an outer peripheral portion 103. The central shaft portion 101 has a female screw hole portion 101a, a male screw portion 101b, and an annular flange portion 101c. The female screw hole portion 101a is coaxially formed in the central shaft portion 101 from its upper end surface. The male screw portion 101b is coaxially formed on the outer peripheral portion of the central shaft portion 101, and an annular flange portion 101c is radially outward from the outer peripheral portion of the central shaft portion 101 directly above the male screw portion 101b. Protruding along.

  The intermediate film portion 102 is thinly formed so as to have sufficient flexibility, and the intermediate film portion 102 has a curved cross section so as to form an annular shape outward from the outer periphery of the upper end of the central shaft portion 101. It is extended integrally. The outer peripheral portion 103 has an annular groove portion 103a. The annular groove portion 103a is formed in an annular groove shape from the lower surface side of the outer peripheral portion 103 so as to correspond to the annular wall portion 53b of the annular L-shaped portion 53. Is formed.

  In the sub-diaphragm 100 configured as described above, the central shaft portion 101 has the male shaft portion 91b so that the central shaft portion 101 is seated on the upper end surface of the central shaft portion 91 of the main diaphragm 90. The male screw portion 63a of the proximal end side shaft portion 63 of the rod 60 is fastened to the female screw hole portion 101a of the central shaft portion 101. Further, the outer peripheral portion 103 inserts the outer peripheral portion of the annular groove portion 103 a between the inner peripheral surface of the central through hole portion 52 of the middle housing member 50 and the outer peripheral surface of the annular wall portion 53 b of the annular L-shaped portion 53. In this way, the annular groove portion 103a is fitted to the annular wall portion 53b of the annular L-shaped portion 53 from above. As a result, when the upper housing member 30 is assembled to the middle housing member 50 as described above, the outer peripheral portion 103 is liquid tightly fixed to the annular L-shaped portion 53 by the lower surface of the small-diameter wall portion 32 of the upper housing member 30. It is pressed. In the present embodiment, the outer diameter of the sub diaphragm 100 is selected to be smaller than the outer diameter of the main diaphragm 90 so that the displacement of the sub diaphragm 100 does not decrease the volume of the pump chamber R2 by the main diaphragm 90 due to the displacement. .

  As shown in FIG. 1, the pump device includes an upstream opening / closing valve 110, a downstream opening / closing valve 120, and an orifice 130. The upstream opening / closing valve 110 is composed of an electromagnetic opening / closing valve, and the upstream opening / closing valve 110 includes a valve portion 111 and a drive portion 112 that electromagnetically opens and closes the valve portion 111. The valve part 111 is connected between a pipe 113 extending from the chemical solution in the chemical tank 10 and a pipe 114 extending from the downstream boss part 50 b of the diaphragm pump P.

  Thus, the upstream side opening / closing valve 110 is electromagnetically opened by the driving unit 112 at the valve unit 111 to allow the pipes 113 and 114 to communicate with each other. Further, the upstream opening / closing valve 110 is electromagnetically closed by the drive unit 112 at the valve unit 111 to block communication between the pipes 113 and 114.

  The downstream on-off valve 120 is composed of an electromagnetic on-off valve similar to the upstream on-off valve 110. The downstream on-off valve 120 includes a valve part 121 and a drive part 122 that electromagnetically opens and closes the valve part 121. It is comprised by. The valve part 121 is connected between a pipe 123 extending from the upstream boss part 50 c and a pipe 124 extending from the orifice 130.

  Accordingly, the downstream on-off valve 120 is electromagnetically opened by the drive unit 122 at the valve unit 121 to connect the pipes 123 and 124. In addition, the downstream opening / closing valve 120 is electromagnetically closed by the drive unit 122 at the valve unit 121 to block communication between the pipes 123 and 124.

  The orifice 130 is connected between a pipe 124 extending from the valve portion 121 and a pipe 125 communicating with the inside of the processing cup 20, and the opening inner diameter of the orifice 130 is, for example, 0.2 (mm). It is set small. In addition, the valve opening inner diameter of the valve part of the downstream opening / closing valve 120 is larger than the opening inner diameter of the orifice 130 and is equal to or smaller than the inner diameter of the downstream boss part 50c.

  Further, as shown in FIG. 1, the pump device includes an operation switch SW, a position sensor 140, a controller 150, and both drive circuits 160, 170. The operation switch SW, the position sensor 140, the controller 150, and both drives are provided. The circuits 160 and 170 constitute a control circuit for the pump device.

  The operation switch SW is operated and turned on when operating the pump device. The position sensor 140 is composed of a photoelectric sensor, and the position sensor 140 includes a light projecting system 140a and a light receiving system 140b as schematically shown in FIG. The light projecting system 140 a includes a light projecting unit 141 and a light projecting lens 142, and the optical axes of the light projecting unit 141 and the light projecting lens 142 are located on the axis of the rod 60. The light projecting unit 141 projects light toward the light projecting lens 141a. The light projecting lens 142 is composed of a convex lens, and the light projecting lens 142 emits light from the light projecting portion 141 and condenses it on the central portion of the end surface portion 61 a of the distal end side shaft portion 61 of the rod 60. The collected light is reflected as diffused light by the central portion of the end surface portion 61 a of the distal end side shaft portion 61.

  The light receiving system 140 b includes a light receiving lens 143 and a position detection unit 144, and the light receiving lens 143 is a normal line to the optical axis of the light projecting lens 142 at the center and passes through the center of the light projecting lens 142. It is adjacent to the light projection lens 142 so as to be positioned on the normal line. As a result, the light receiving lens 143 receives the reflected diffused light from the end surface portion 61 a of the distal end side shaft portion 61 and emits it toward the position detecting portion 144. The position detection unit 144 is configured by arranging a plurality of semiconductor light receiving elements in a one-dimensional manner. Accordingly, when one semiconductor light receiving element among the plurality of semiconductor light receiving elements receives the reflected diffused light from the light receiving lens 143, the position detecting unit 144 slides the rod 60 based on the light reception output of the one semiconductor light receiving element. Detect the moving position.

  The controller 150 includes a microcomputer, and the controller 150 executes a computer program according to the flowcharts shown in FIGS. During this execution, the controller 150 turns on the upstream side open / close valve 110 or the downstream side open / close valve based on the driving process of the air flow supply source 80 and the detected sliding position of the position sensor 140 under the ON operation of the operation switch SW. Arithmetic processing such as opening / closing valve processing of the valve 120 is performed. The computer program is stored in advance in the ROM of the controller 150 so as to be readable.

  The drive circuit 160 drives the drive unit 112 so as to open or close the upstream opening / closing valve 110 under the control of the controller 150. The drive circuit 170 drives the drive unit 122 to open or close the downstream opening / closing valve 120 under the control of the controller 150.

  In the first embodiment configured as described above, when the operation switch W is turned on, the controller 150 starts executing the computer program according to the flowcharts of FIGS. 4 and 5. Then, in step 200 of FIG. 4, it is determined whether or not the mode is the initial mode. In the first embodiment, the initial mode refers to a mode in which the diaphragm pump P has completed the inhalation of the chemical liquid into the pump chamber R2, as shown in FIG. At this time, both the upstream side open / close valve 110 and the downstream side open / close valve 120 are in the closed state, the air flow supply source 80 is in the supply stop state of the air flow, and the main diaphragm 90 is the urging force of the coil spring 70. Due to the downward sliding of the rod 60 based on the above, the rod 60 is displaced downward and abuts on the pedestal portion 41 c in the recess 41 of the lower housing member 40. Therefore, the position sensor 140 detects the sliding end position of the rod 60 below.

  If the diaphragm pump P is in the initial mode at the current stage, the determination in step 200 is YES. At this stage, if the diaphragm pump P is not in the initial mode, the determination in step 200 is NO, and in the next step 201, processing for shifting to the initial mode is performed. Therefore, the drive unit 112 of the upstream side opening / closing valve 110 is controlled by the controller 150 under the closed state of the downstream side opening / closing valve 120 and the supply stop state of the air flow from the air flow supply source 80. Driven by the drive circuit 160, the valve portion 114 opens.

  Accordingly, in the diaphragm pump P, the main diaphragm 90 is displaced downward as the rod 60 slides downward based on the biasing force of the coil spring 70, and the volume of the pump chamber R2 is increased. Therefore, the chemical solution in the chemical solution tank 10 is sucked into the pump chamber R2 through the pipe 113, the upstream side open / close valve 110 and the pipe 114, the upstream boss part 50b of the diaphragm pump P, and the suction hole part 54a. After that, when the main diaphragm 90 comes into contact with the pedestal 41c of the central recess 41 and the suction of the chemical liquid into the pump chamber R2 is completed, the upstream opening / closing valve 110 is closed. As a result, the diaphragm pump P enters the initial mode.

  When the determination of YES in step 200 or the transition to the initial mode in step 201 is performed as described above, the air flow supply source 80 is driven by the controller 150 in the air flow supply process in the next step 202. The air flow is pumped into the pressing chamber R1 through the supply hole 44 of the lower housing member 40 of the diaphragm pump P.

  In addition, in the opening process of the downstream opening / closing valve in step 203, the downstream opening / closing valve 120 is driven by the drive circuit 170 under the control of the controller 150 by the driving unit 122 in the opening process of the downstream opening / closing valve in step 203. Then, the valve part 121 is opened.

  Along with this, the main diaphragm 90 starts to displace upward while sliding the rod 60 against the urging force of the coil spring 70 so as to reduce the volume of the pump chamber R2, and the chemical liquid is pumped. It is discharged from the chamber R2 through the discharge hole 54b and into the pipe 123 from the downstream boss part 50c, and begins to flow into the orifice 130 through the valve part 121 and the pipe 124 of the downstream on-off valve 120. Moreover, the detection sliding position of the rod 60 by the position sensor 140 changes. The discharge flow rate of the chemical liquid from the pump chamber R2 is, for example, about 4 (ml) per minute.

  Here, since the opening inner diameter of the orifice 130 is as small as 0.2 (mm) as described above, the chemical liquid flowing into the orifice 130 is throttled to a constant minute flow rate by the orifice 130 and passes through the pipe 125 to form a processing cup. It is dripped toward the inside of 20. Thereby, the chemical treatment of the semiconductor wafer W is started by the rotation of the spin table 21. Here, since the flow rate of the chemical solution passing through the orifice 130 is a constant minute flow rate as described above, the amount of the chemical solution dropped from the pipe 125 into the processing cup 20 is also a constant minute amount. For this reason, the chemical treatment of the semiconductor wafer W can be made constant with high accuracy.

  After the processing in step 203 described above, it is determined in step 210 whether or not the discharge of the chemical liquid has been completed. If the rod 60 has reached the upward sliding end position (see FIG. 7) at the current stage, YES is determined in step 210 based on the sliding position detected by the position sensor 140. Accordingly, the computer program proceeds to step 212 (see FIG. 5).

  On the other hand, if the rod 60 has not reached the upward sliding end position, the discharge of the chemical solution has not been completed. Therefore, NO is determined in step 210 based on the sliding position detected by the position sensor 140. Then, in the internal timer reset start process in step 211, the internal timer of the controller 150 is reset and started. As a result, the built-in timer starts timing.

  After step 211, in step 220, it is determined whether T ≧ To. Here, T is a time value of the built-in timer. Further, To represents a predetermined abnormal time for specifying an abnormal state of the diaphragm pump P. The abnormal state of the diaphragm pump P is induced on the basis of the stop of the rod 60 that occurs when the orifice 130 is clogged.

  At the present stage, since it is immediately after the built-in timer starts timing, the determination in step 220 is NO. If the discharge of the chemical liquid has not yet been completed, NO is determined in step 230 as in the above-described determination in step 210.

  Thereafter, during the process of circulating both steps 220 and 230, prior to the determination of YES in step 230, if it is determined YES in step 220 based on the establishment of T ≧ To, the rod 60 is in a predetermined abnormal time. Since it remains substantially stopped during To, the diaphragm pump P is in an abnormal state. For this reason, stop processing is performed in the next step 221. Accordingly, the processing based on the computer program by the controller 150 is stopped. Thereby, the subsequent operation of the diaphragm pump P can be prohibited. As a result, it is possible to take measures against the abnormal state of the diaphragm pump P with good timing.

  On the other hand, prior to the determination of YES in step 220, the rod 60 reaches the upward sliding end position (see FIG. 7) under the absence of T ≧ To, and from the pressing chamber R1 side of the main diaphragm 90 If the displacement toward the pump chamber R2 is completed, the discharge of the chemical solution in the pump chamber R2 is completed. Therefore, the computer program proceeds to step 212 (see FIG. 5).

  As described above, when the computer program proceeds from step 210 or step 230 to step 212, the downstream side opening / closing valve is closed. Here, the downstream on-off valve 120 is driven by the drive circuit 170 under the control of the controller 150 by the drive unit 122 to close the valve unit 121. For this reason, the orifice 130 is shut off from the diaphragm pump P.

  After the process in step 212, in the air flow supply stop process in step 213, the air flow supply source 80 is controlled by the controller 150 to stop the pumping of the air flow to the diaphragm pump P. Next, in the valve opening process of the upstream side opening / closing valve in step 214, the upstream side opening / closing valve 110 is driven by the driving circuit 160 under the control of the controller 150 by the driving unit 112 to open the valve unit 111. I speak. Accordingly, the chemical solution in the chemical solution tank 10 can flow into the diaphragm pump P from the upstream boss portion 50b through the piping 113, the upstream side opening / closing valve 110, and the piping 114.

  Thus, the diaphragm pump P is cut off from the orifice 130 and the air flow supply source 80 as described above, whereby the pump chamber R2 is cut off from the orifice 130 and the pressing chamber R1 is cut off from the air flow supply source 80. It will be. For this reason, it means that the volume of the pump chamber R2 increases as the rod 60 decreases downward under the biasing force of the coil spring 70. Along with this, the diaphragm pump P exhibits a suction function due to the increase in the volume of the pump chamber R2, so that the chemical solution in the chemical solution tank 10 starts to be sucked into the pump chamber R2 through the upstream opening / closing valve 110.

  After the process of step 214 described above, it is determined in step 220 whether or not the inhalation of the chemical solution is complete. At this stage, if the main diaphragm 90 is not in contact with the pedestal portion 41c of the recess 41 at the central shaft portion 91 and the thick wall portion 92a, the position sensor 140 is located at the sliding end position below the rod 60. Is not detected, the determination in step 220 is NO.

  After that, when the main diaphragm 90 abuts on the pedestal 41c of the recess 41 at the central shaft portion 91 and the thick wall portion 92a, the position sensor 140 detects the position of the sliding end of the rod 60 below. Therefore, YES is determined in step 240. Thereby, the inhalation of the chemical liquid into the pump chamber R2 by the diaphragm pump P is completed.

  Thereafter, in the valve closing process of the upstream side opening / closing valve in step 241, the upstream side opening / closing valve 110 is closed by the drive circuit 160 under the control of the controller 150. If the upstream side opening / closing valve 110 is closed in this way, the downstream side opening / closing valve 120 is already closed in the process of step 212, and the air flow supply source 80 stops the pressure flow of the air flow in the process of step 213, And since the determination in step 240 is YES because the position sensor 140 detects the sliding end position of the rod 60 below, the diaphragm pump P returns to the initial state.

  As described above, in the first embodiment, when the chemical pump is inhaled or discharged by the diaphragm pump P, the urging force of the coil spring 70 is applied from the pump chamber R2 side to the proximal end side shaft portion 63 of the rod 60 and the sub diaphragm 90. It always acts on the main diaphragm 90 via the central shaft portion 91. On the other hand, when the pressure of the air flow into the pressing chamber R2 discharges the liquid chemical in the pump chamber as described above, It acts on the diaphragm 90. This is because when the chemical solution in the pump chamber R2 is discharged, the urging force via the proximal end side shaft portion 63 of the rod 60 and the pressure of the air flow into the pressing chamber R1 are mutually connected via the same main diaphragm 90. It means acting toward the main diaphragm so as to face each other correctly.

  In other words, the through hole 33 for urging by the coil spring 70 and the supply hole 44 for supplying the air flow into the pressing chamber R1 are separately divided on both sides of the main diaphragm 90 with respect to the housing H. By providing the diaphragm, the housing H can be simply configured by effectively utilizing both the urging force of the coil spring 70 acting in the opposite direction from both sides of the main diaphragm 90 and the pressure of the air flow in the through hole 33. A pump can be provided.

  Further, since the evacuation configuration as described in the prior art is not adopted, waste of air consumed in evacuation is suppressed. Further, as described above, the biasing force of the coil spring 70 and the pressure of the air flow into the pressing chamber R1 act in a direction in which the main diaphragm 90 and the rod 60 are brought closer to each other. As a result, the mechanical strength of the coupling between the main diaphragm 90 and the rod 60 in the diaphragm pump P can be reduced to a necessary minimum.

  Further, as described above, the outer diameter of the sub diaphragm 100 is selected to be smaller than the outer diameter of the main diaphragm 90 so that the displacement of the sub diaphragm 100 does not reduce the volume of the pump chamber R2 by the main diaphragm 90 due to the displacement. Yes. Therefore, the volume in the pump chamber R2 required for the suction of the chemical solution into the pump chamber R2 and the discharge of the chemical solution from the pump chamber R2 can be properly maintained.

  Further, since the inside of the pump chamber R2 is liquid-tightly sealed from the large-diameter hole portion 33a of the through-hole portion 33 by the sub diaphragm 100, foreign matter such as dust enters the pump chamber R2 from the inside of the through-hole portion 33. Will not invade. In particular, the rod 60 is integrated with the central portion of the sub-diaphragm 100 at the base end side shaft portion 63. For this reason, the rod does not slide relative to the central shaft portion 101 of the sub diaphragm. As a result, it is possible to reliably prevent foreign matter from entering the pump chamber R2 due to sliding friction between the O-ring and the rod 60, which tends to occur when the sub-diaphragm 100 is an O-ring. Such an effect is particularly remarkable when the diaphragm pump is applied to a semiconductor manufacturing apparatus that strictly requires chemical cleaning as in the first embodiment.

  In addition, as described above, the orifice 130 restricts the supply flow rate of the chemical solution from the downstream on-off valve 120 to the processing cup 20 to a constant minute flow rate, so that the semiconductor wafer W in the processing cup 20 is processed favorably. The effects described above can be achieved.

  Further, as described above, the suction of the chemical liquid into the pump chamber R2 and the stop thereof are performed by opening and closing the upstream opening / closing valve 110, and the discharge of the chemical liquid from the pump chamber R2 to the orifice 130 and the stop thereof are performed. This is performed by opening and closing the downstream opening / closing valve 120. For this reason, in achieving the above-described effects, the chemical liquid can be sucked and discharged by the diaphragm pump P more accurately.

  Further, as described above, the means for urging the rod 60 and the sub diaphragm 90 toward the pump chamber R2 in the large diameter hole 33b of the through hole 33 of the housing H depends on the coil spring 70. In addition, the sub-diaphragm 90 is used as a sealing means for the large-diameter hole 33b from the pump chamber R2. For this reason, the sliding resistance between the rod 60 and the through-hole portion 33 is reduced to a minimum. For example, when the large-diameter hole portion 33b is sealed from the pump chamber R2 via the rod 60 by an O-ring. In comparison, the sliding resistance acting on the rod 60 is remarkably small. This is particularly effective when the discharge amount of the chemical liquid is limited to a minute flow rate as in the present embodiment.

  Further, in the above prior art, since the air pressure and the vacuum pressure act on the diaphragm from the same side, when the air pressure (or vacuum pressure) acting on the diaphragm changes to the vacuum pressure (or air pressure), the diaphragm suddenly changes. Displaces rapidly in response to pressure changes. This is because the diaphragm displacement becomes unstable, and the suction into the pump chamber and the discharge from the pump chamber tend to become unstable. To prevent this, the flow of air is relaxed by the orifice.

However, in the present embodiment, as described above, the biasing force of the coil spring 70 and the pressure of the air flow into the pressing chamber R1 act in opposite directions from both sides of the main diaphragm 90, so that the displacement of the main diaphragm 90 is Does not change abruptly, and the displacement of the main diaphragm 90 is very stable. Accordingly, the suction of the chemical liquid into the pump chamber R2 and the discharge of the chemical liquid from the pump chamber R2 are extremely stable. As a result, it is not necessary to employ an extra orifice in the prior art.
(Second Embodiment)
FIG. 8 shows a main part of the second embodiment of the present invention. This 2nd Embodiment has the structure which replaced with the diaphragm pump P in the pump apparatus described in the said 1st Embodiment, and employ | adopted the diaphragm pump Pa. FIG.

  Diaphragm pump Pa employs a coil spring 70a instead of coil spring 70 and a supply hole 34 instead of supply hole 44 in diaphragm pump P described in the first embodiment.

  The coil spring 70a is coaxially fitted in the annular groove portion 45 of the lower housing member 40 described in the first embodiment at the lower portion thereof, and the coil spring 70a is mainly inserted from the lower portion thereof. It extends toward the diaphragm 90. As a result, the coil spring 70a is engaged with the bottom surface of the annular groove 45 and the lower surface of the thick part 92a of the main diaphragm 90 at both the upper and lower axial ends, and the main diaphragm 90 is directed upward. It is fast. The annular groove 45 is formed in the recess 41 of the lower housing member 40 coaxially with the pedestal 41c from the portion of the bottom surface around the pedestal 41c.

  The supply hole portion 34 is formed in the upper housing member 30 described in the first embodiment, and the supply hole portion 34 is large at the inner end portion of the through hole portion 33 of the upper housing member 30. It communicates with the inside of the radial hole 33b. In the second embodiment, the distal end side shaft portion 61 of the rod 60 is fitted into the small diameter hole portion 33a of the through hole portion 33 of the upper housing member 30 so as to be airtightly slidable through the O-ring 61a. . Thereby, the inside of the large-diameter hole portion 33 b of the through-hole portion 33 is hermetically blocked from the outside of the upper housing member 30. The O-ring 61a is attached to an annular groove portion 31a formed on the inner peripheral surface of the small diameter hole portion 33a.

  Further, the outer end portion of the supply hole portion 34 is changed from a part of the outer peripheral surface of the upper housing member 30 to the air flow supply source 80 in place of the outer end portion of the supply hole portion 44 described in the first embodiment. The pipe 81 is in communication. As a result, the sub diaphragm 100 described in the first embodiment is configured such that the coil spring is moved from the air flow supply source 80 through the supply hole 34 and into the large-diameter hole 33b of the through hole 33 by the air flow. It is urged against the urging force of 70a and displaced downward.

  In the second embodiment, the urging force of the coil spring 70a acts on the main diaphragm 90 in the opposite direction to the urging force of the coil spring 70 described in the first embodiment. In the second embodiment, the air flow pressure acts on the sub diaphragm 100 in the opposite direction to the air flow pressure described in the first embodiment.

  For this reason, the flowchart employed in the second embodiment is the same as the flowchart described in the first embodiment, except that the air flow supply process and the air flow supply stop process in steps 202 and 213 are respectively performed as the air flow supply. The configuration is changed to the stop process and the air flow supply process. Therefore, in the second embodiment, the controller 150 executes the computer program according to the flowchart changed as described above. Other configurations are the same as those in the first embodiment.

  In the second embodiment configured as described above, it is determined in step 200 whether or not it is the initial mode, as in the first embodiment. Here, in the second embodiment, the initial mode refers to a mode in which the diaphragm pump Pa has completed the suction of the chemical solution into the pump chamber R2. At this time, both the upstream side open / close valve 110 and the downstream side open / close valve 120 are closed, the air flow supply source 80 is in the air flow supply state, and the sub-diaphragm 100 is supplied from the air flow supply source 80. The main diaphragm 90 is in a state in which the rod 60 is slid downward by being displaced downward against the urging force of the coil spring 70 a based on the pressure of the air flow into the large-diameter hole 33 b of the through-hole 33. Is displaced downward by sliding downward of the rod 60 and abuts on the pedestal 41c in the recess 41 of the lower housing member 40. Accordingly, the position sensor 140 detects the sliding end position of the rod 60 below as in the first embodiment.

  Thus, after the determination of YES in step 200 or the transition process to the initial mode in step 201, the air flow supply stop process is performed in step 202, unlike the first embodiment, and in the next step 203, The downstream on-off valve 120 is opened as in the first embodiment.

  For this reason, the main diaphragm 90 starts to be displaced upward together with the rod 60 based on the urging force of the coil spring 70 so as to reduce the volume of the pump chamber R2. At this time, the air in the large-diameter hole portion 33 b of the through-hole portion 33 is exhausted from the supply hole portion 34 due to the upward displacement of the sub-diaphragm 100 accompanying the upward displacement of the main diaphragm 90.

  Along with this, the chemical liquid is discharged from the pump chamber R2 through the discharge hole portion 54b and into the pipe 123 from the downstream boss portion 50c, passes through the downstream on-off valve 120 and the orifice 130, and becomes a constant minute flow rate. It is dropped into the processing cup 20. As a result, the chemical treatment of the semiconductor wafer W can be performed accurately and constantly.

  As in the first embodiment, when it is determined YES in step 210 or 230 upon completion of the discharge of the chemical liquid in the pump chamber R2, the downstream on-off valve 120 is closed in step 212. Then, in step 213, unlike the first embodiment, air flow supply processing is performed. Therefore, under the control of the controller 150, the air flow is pumped from the air flow supply source 80 through the pipe 81 and the supply hole 34 of the upper housing member 30 and into the large diameter hole 33 b of the through hole 33. . Accordingly, the sub diaphragm 100 is displaced downward against the coil spring 70a and slides the rod 60 downward to increase the volume of the pump chamber R2. In addition, after the process of step 213, the upstream on-off valve 110 is opened in the process of step 214 as in the first embodiment.

  Along with this, the chemical solution in the chemical solution tank 10 is sucked into the pump chamber R2 of the diaphragm pump Pa in substantially the same manner as in the first embodiment. Thereafter, when the determination in step 240 is YES, the upstream on-off valve 110 is closed in the process of step 241. Other operations are the same as those in the first embodiment.

  As described above, in the second embodiment, unlike the first embodiment, the coil spring 70a is disposed in the pressing chamber R1, while the pressure of the air flow from the air flow supply source 80 is It is supplied into the large diameter hole portion 33 b of the through hole portion 33 of the upper housing member 30.

  For this reason, the urging force of the coil spring 70a always acts on the main diaphragm 90 from the pressing chamber R1 side, while the pressure of the air flow into the large-diameter hole portion 33b is mainly transmitted from the pump chamber R2 side via the sub diaphragm 100. Acts on the diaphragm 90. This means that when the chemical liquid in the pump chamber R2 is discharged, the urging force of the coil spring 70a and the pressure of the air flow into the through-hole 33 are opposed to each other via the same main diaphragm 90. It means acting toward the diaphragm. As a result, also in the second embodiment, substantially the same as in the first embodiment, the urging force by the coil spring 70a acting in the opposite direction from both sides of the main diaphragm 90 and the air flow in the through-hole portion 33 are obtained. A diaphragm pump in which the housing H is simply configured can be provided by effectively utilizing both of the pressures generated by the above. Other functions and effects are substantially the same as those of the first embodiment.

In carrying out the present invention, the following various modifications are possible without being limited to the above embodiments.
(1) Instead of the photoelectric sensor described in the above embodiment, the position sensor 140 includes two proximity switches that respectively detect the upward sliding end position and the downward sliding end position of the rod 60. You may comprise with a detection switch.
(2) The position sensor 140 includes a detection switch that detects only one of the upward sliding end position and the downward sliding end position of the rod 60, and the upward sliding end position of the rod 60 and the downward direction. A predetermined elapsed time from reaching the sliding end position to one of the upward sliding end position and the downward sliding end position of the rod 60 may be measured with a timer. According to this, the timer detects the arrival of the sliding end position above the rod 60 and the sliding end position below the rod 60 at the other end at the end of the time counting. Also by this, the same operation effect as the above-mentioned embodiment can be achieved.
(3) The position sensor 140 employs the first and second timers instead of the photoelectric sensor described in the above embodiment, and is moved downward from the sliding end position above the rod 60 by the first timer. The first predetermined elapsed time required to reach the sliding end position of the rod 60 is measured, and the second timer is required to reach the sliding end position of the rod 60 from the sliding end position to the lower side by the second timer. The second predetermined elapsed time may be measured. According to this, the first timer detects the sliding end position of the rod 60 upward when the timing ends, and the second timer moves down the rod 60 when the timing ends. The sliding end position is detected. Also by this, the same operation effect as the above-mentioned embodiment can be achieved.
(4) The position sensor 140 may employ, for example, a pair of photo interrupters or a pair of micro switches instead of the photoelectric sensor. Here, the pair of photo interrupters or the pair of micro switches may detect the sliding end position upward and the sliding end position of the rod 60, respectively.
(5) In carrying out the present invention, the present invention may be applied so as to inhale and discharge pure water and other liquids without being limited to chemical solutions.
(6) The boundary step portion between the small-diameter hole portion 33a and the large-diameter hole portion 33b of the through-hole portion 33 may be located above the above-described sliding end position above the rod 60. In addition, in the rod 60, the distal end side shaft portion 61 and the middle side shaft portion 62 may have the same outer diameter, unlike the above embodiment. Moreover, the upper surface of the base part 41c may be set lower than the position corresponding to the sliding end position of the rod 60 below, and the base part 41c may be eliminated.
(7) In carrying out the present invention, the inner diameter of the orifice 130 may not be set small so as to flow a certain minute flow rate of the chemical solution as described in the above embodiment, or the orifice 130 is necessary. It may be abolished accordingly.
(8) A flow rate control valve (for example, a proportional control valve) is employed instead of the downstream opening / closing valve 120, and the opening degree of the flow rate control valve is gradually increased when the chemical solution is discharged from the pump chamber R2. By doing so, it is possible to prevent a rapid increase in the pressure in the pipe 123 when the chemical liquid is discharged from the pump chamber R2.
(9) In the first embodiment, the coil spring 70 is eliminated, and an air flow from another air flow supply source different from the air flow supply source 80 is allowed to enter the large-diameter wall portion 31 of the upper housing member 30. You may comprise so that it pumps and supplies inside the large diameter hole part 33b of the through-hole part 33 through the formed communicating path.

  According to this, when the chemical liquid is sucked into the pump chamber R2, the air flow fed into the large-diameter hole 33b is stopped while the supply of the air flow into the pressing chamber R1 is stopped. It acts directly on the sub-diaphragm 100 from between the inner peripheral surface of the large-diameter hole portion 33b and the outer peripheral surface of the inner shaft portion 62 (including the annular flange portion 62a) of the rod 60. For this reason, the sub-diaphragm 100 is displaced to the pump chamber R2 side, and the central shaft portion 101 pushes the central shaft portion 91 of the main diaphragm 90 to the pressing chamber R1 side to discharge the air in the pressing chamber R1. The volume of the chamber R2 is increased. In addition, when the chemical solution is discharged into the pump chamber R2, the air flow that is pressure-fed and supplied into the pressing chamber R1 with the supply of the air flow into the large-diameter hole 33b is stopped by the main diaphragm 90. Press toward the pump chamber R2. For this reason, the main diaphragm 90 is displaced upward together with the sub-diaphragm 100 to reduce the volume of the pump chamber R2 while discharging the air in the large-diameter hole portion 33b.

As a result, as described above, even if the coil spring 70 is abolished and an air flow is pressure-fed and supplied into the large-diameter hole portion 33b of the through-hole portion 33, the same effect as the first embodiment is achieved. Can be done.
(10) Unlike the first embodiment, the coil spring 70 may be engaged with the boundary step portion 33d and the central shaft portion 91 of the sub diaphragm 90 at both ends thereof. In this case, the outer diameter of the annular flange 62a of the rod 60 may be the same outer diameter as that of the middle shaft portion 62 or the distal end shaft portion 63, for example.
(11) In the first embodiment, the annular flange 62 a and the base end side shaft portion 63 of the rod 60 may be grasped so as to be included in the central shaft portion 101 of the sub diaphragm 100. In this case, the rod 60 is configured by the middle shaft portion 62 (excluding the annular flange portion 62a) and the proximal end shaft portion 61.
(12) In the first or second embodiment, in the case where the present invention is used as a diaphragm pump, if the position sensor 140 is unnecessary, a cylindrical portion that opens into the pump chamber R2 instead of the through-hole portion 33. A recess such as (having a bottom) may be formed across the large-diameter wall 31 and the small-diameter wall 32. In addition, the large diameter hole part 33b of the through-hole part 33 respond | corresponds to the said recessed part, for example. However, the small-diameter hole 33a is closed to the bottom of the large-diameter hole 33b.

1 is a block circuit diagram showing a first embodiment of a pump device provided with a diaphragm according to the present invention. It is an expanded sectional view of the diaphragm pump of FIG. It is a typical schematic block diagram of the position sensor of FIG. It is a front | former part of the flowchart showing the computer program which the controller which is a microcomputer of FIG. 1 performs. It is the latter part of the flowchart. It is sectional drawing which shows the initial mode of the diaphragm pump of FIG. It is sectional drawing which shows the time of discharge completion of the diaphragm pump of FIG. It is sectional drawing which shows the principal part of 2nd Embodiment of this invention.

Explanation of symbols

H: Housing, P, Pa: Diaphragm pump, R1: Pressing chamber, R2: Pumping chamber,
To ... Predetermined abnormal time, 10 ... Chemical tank, 20 ... Processing cup, 31 ... Large diameter wall,
32 ... Small diameter wall part, 33 ... Through-hole part, 33a ... Small diameter hole part, 33b ... Large diameter hole part,
33d: annular boundary step, 34, 44 ... supply hole, 50b ... upstream boss,
50c ... downstream boss, 54a ... suction hole, 54b ... discharge hole, 60 ... rod,
61 ... distal end side shaft portion, 62 ... middle side shaft portion, 63 ... proximal end side shaft portion,
70, 70a ... Coil springs, 80 ... Air flow source, 90 ... Main diaphragm,
DESCRIPTION OF SYMBOLS 100 ... Sub-diaphragm, 101 ... Central axial part, 103 ... Outer peripheral part, 110 ... Upstream side on-off valve,
114, 123, 124 ... piping, 120 ... downstream side on-off valve, 130 ... orifice,
140: position sensor, 150: controller.

Claims (8)

A housing;
A main diaphragm which is provided in the housing and divides the interior of the housing into a pressing chamber and a pump chamber;
The recess is provided between the pump chamber and a recess formed in a concave shape so as to open in the pump chamber within a coaxial wall portion coaxially facing the main diaphragm via the pump chamber in the housing. A sub-diaphragm that liquid-tightly partitions the pump chamber;
Urging means for urging the sub-diaphragm from the inside of the recess of the housing to the pump chamber side;
The sub-diaphragm is coaxially connected from the pump chamber to the central portion of the main diaphragm at the center thereof, and has an outer diameter smaller than that of the main diaphragm,
A supply hole for supplying an air flow from an air flow supply source into the pressing chamber is formed in a peripheral wall portion of the pressing chamber in the housing,
A diaphragm pump in which a suction portion for sucking liquid from a liquid supply source into the pump chamber and a discharge portion for discharging the liquid in the pump chamber are formed in a peripheral wall portion of the pump chamber in the housing.   2. The diaphragm pump according to claim 1, wherein the biasing means is a coil spring that is provided in the recess of the housing and biases the sub diaphragm toward the pump chamber. The diaphragm pump according to claim 1 or 2,
An upstream valve means that opens when the liquid flows into the pump chamber of the diaphragm pump from the suction portion and closes when the liquid stops flowing;
A downstream valve means that opens when supplying the liquid discharged from the pump chamber through the discharge section to the supply system and closes when the supply of the liquid to the supply system is stopped; A pump device provided with a diaphragm pump.   4. A pump apparatus having a diaphragm pump according to claim 3, further comprising orifice means for restricting a supply flow rate of the liquid from the downstream valve means to the supply system to a constant minute flow rate. A rod extending coaxially from the central portion of the sub-diaphragm to the opposite side of the main diaphragm into the recess, a position detection means, a first control means, and a second control means,
The concave portion of the housing is opened coaxially with the sub-diaphragm at the bottom thereof and communicates with the inside of the concave portion and communicates with the outside of the bottom portion,
The rod has a tip side shaft portion that is slidably fitted in the bottom portion so as to be able to extend from the bottom portion through the concave portion,
The position detecting means is provided at or near the bottom of the concave portion, and when the diaphragm pump has completed the suction of the liquid into the pump chamber, the sliding position of the tip side shaft portion of the rod is The first sliding position of the rod is detected, and when the diaphragm pump completes the discharge of the liquid in the pump chamber, the sliding position of the tip side shaft portion of the rod is the second sliding position of the rod. Is supposed to detect as
The first control means stops supplying the air flow into the pressing chamber in order to suck the liquid into the pump chamber when the position detecting means detects the second sliding position of the rod. And the air flow supply source, the upstream valve means and the downstream valve means are controlled to open the upstream valve means and close the downstream valve means,
The second control means is configured to discharge the liquid in the pump chamber into the pressing chamber when the position detection means detects the first sliding position of the rod after the control by the first control means. The air flow supply source, the upstream valve means and the downstream valve means so as to start supplying the air flow, close the upstream valve means, and open the downstream valve means. 5. A pump device comprising the diaphragm pump according to claim 3, wherein the pump device is controlled.   6. The diaphragm pump according to claim 5, wherein the operation of the diaphragm pump is prohibited when the discharge of the liquid in the pump chamber accompanying the control of the second control means is not completed before a predetermined abnormal time elapses. Pump device with A housing;
A main diaphragm which is provided in the housing and divides the interior of the housing into a pressing chamber and a pump chamber;
The recess is provided between a recess formed in a concave shape so as to open in the pump chamber in a coaxial wall portion coaxially facing the main diaphragm via the pump chamber in the housing and the pump chamber. A sub-diaphragm that is liquid-tightly partitioned from the pump chamber;
A biasing means provided in the pressing chamber and biasing so as to press the main diaphragm toward the pump chamber;
The sub-diaphragm is coaxially connected from the pump chamber to the central portion of the main diaphragm at the center thereof, and has an outer diameter smaller than that of the main diaphragm,
The peripheral wall portion of the pump chamber of the housing has a suction portion for sucking liquid from the liquid supply source into the pump chamber, a discharge portion for discharging the liquid in the pump chamber, and an air flow supply source (80). The diaphragm pump in which the supply hole part which supplies an air flow in the said recessed part is formed. 8. The diaphragm pump according to claim 7, wherein the diaphragm pump has a rod extending coaxially from the center portion of the sub-diaphragm toward the opposite side of the main diaphragm into the recess, upstream valve means, and downstream side Comprising valve means and orifice means, position detection means, first control means and second control means,
The concave portion of the housing is opened coaxially with the sub-diaphragm at the bottom thereof and communicates with the inside of the concave portion and communicates with the outside of the bottom portion,
The rod has a tip side shaft portion that is slidably fitted in the bottom portion so as to be able to extend from the bottom portion through the concave portion,
The upstream valve means opens when the liquid flows into the pump chamber of the diaphragm pump from the suction portion, and closes when stopping the inflow of the liquid,
The downstream valve means opens when supplying the liquid discharged from the pump chamber through the discharge portion to the supply system, and closes when supplying the liquid to the supply system is stopped. Is supposed to
The orifice means is adapted to restrict the supply flow rate of the liquid from the downstream valve means to the supply system to a fixed minute flow rate,
The position detecting means is provided at or near the bottom of the concave portion, and when the diaphragm pump has completed the suction of the liquid into the pump chamber, the sliding position of the tip side shaft portion of the rod is The first sliding position of the rod is detected, and when the diaphragm pump completes the discharge of the liquid in the pump chamber, the sliding position of the tip side shaft portion of the rod is the second sliding position of the rod. Is supposed to detect as
The first control means supplies the air flow into the recess to suck the liquid into the pump chamber when the position detection means detects the second sliding position of the rod, The air flow source, the upstream valve means and the downstream valve means are controlled to open the upstream valve means and close the downstream valve means,
The second control means enters the recess to discharge the liquid in the pump chamber when the position detection means detects the first sliding position of the rod after control by the first control means. The air flow supply source, the upstream valve means and the downstream valve means so as to stop the supply of the air flow, close the upstream valve means, and open the downstream valve means. A pump device equipped with a diaphragm pump to be controlled.

Images