U.S. patent application number 16/765863 was filed with the patent office on 2020-12-17 for valve, abnormality diagnosis method of valve, and computer program.
This patent application is currently assigned to Fujikin Incorporated. The applicant listed for this patent is Fujikin Incorporated. Invention is credited to Kenji Aikawa, Akihiro Harada, Katsunori Komehana, Takahiro Matsuda, Masahiko Ochiishi, Tsutomu Shinohara, Yuya Suzuki, Ryutaro Tanno.
Application Number | 20200393060 16/765863 |
Document ID | / |
Family ID | 1000005066129 |
Filed Date | 2020-12-17 |
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United States Patent
Application |
20200393060 |
Kind Code |
A1 |
Tanno; Ryutaro ; et
al. |
December 17, 2020 |
Valve, Abnormality Diagnosis Method of Valve, and Computer
Program
Abstract
To enable accurate and simple diagnosis of an operation
abnormality of a valve. A valve V1 capable of detecting an
operation abnormality has a magnet M1 that is attached in the
vicinity of a pressing adapter 52 of a stem 53 that slides
according to an opening/closing operation of the valve V1, and a
magnetic sensor M2 that is attached to a surface acing the stem 53,
inside the pressing adapter 52 that presses a peripheral edge of a
diaphragm 51, and detects a change in a distance between the magnet
M1 and the magnetic sensor M2. Further, an abnormality
determination mechanism compares the change in the distance between
the magnet M1 and the magnetic sensor M2 at the time of abnormality
diagnosis detected by the magnetic sensor M2 and a previously
measured change in the distance between the magnet M and the
magnetic sensor M2 at the time of normality, and determines whether
or not there is an abnormality.
Inventors: |
Tanno; Ryutaro; (Osaka,
JP) ; Aikawa; Kenji; (Osaka, JP) ; Harada;
Akihiro; (Osaka, JP) ; Suzuki; Yuya; (Osaka,
JP) ; Matsuda; Takahiro; (Osaka, JP) ;
Komehana; Katsunori; (Osaka, JP) ; Ochiishi;
Masahiko; (Osaka, JP) ; Shinohara; Tsutomu;
(Osaka, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Fujikin Incorporated |
Osaka |
|
JP |
|
|
Assignee: |
Fujikin Incorporated
Osaka
JP
|
Family ID: |
1000005066129 |
Appl. No.: |
16/765863 |
Filed: |
October 5, 2018 |
PCT Filed: |
October 5, 2018 |
PCT NO: |
PCT/JP2018/037417 |
371 Date: |
May 20, 2020 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G01M 13/003 20190101;
F16K 7/16 20130101; F16K 37/0033 20130101 |
International
Class: |
F16K 37/00 20060101
F16K037/00; F16K 7/16 20060101 F16K007/16; G01M 13/003 20060101
G01M013/003 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 29, 2017 |
JP |
2017-229482 |
Claims
1. A valve capable of detecting an operation abnormality,
comprising: a stem sliding according to an opening/closing
operation of the valve; a pressing adapter pressing a peripheral
edge of a diaphragm; a position sensor attached to the pressing
adapter and detecting a change in a distance between a
predetermined location of the stem and the position sensor; and an
abnormality determination mechanism comparing the change in the
distance between the predetermined location and the position sensor
at the time of abnormality diagnosis detected by the position
sensor and a previously measured change in the distance between the
predetermined location and the position sensor at the time of
normality, and determines whether or not there is an
abnormality.
2. The valve according to claim 1, further comprising: a magnet
attached to a predetermined location in the vicinity of the
pressing adapter, wherein the position sensor comprises a magnetic
sensor that is attached to a surface facing toward the stem, inside
of the pressing adapter, and detects a change in a distance between
the magnet and the magnetic sensor; and the abnormality
determination mechanism compares the change in the distance between
the magnet and the magnetic sensor at the time of abnormality
diagnosis detected by the magnetic sensor and a previously measured
change in the distance between the magnet and the magnetic sensor
at the time of normality, and determines whether or not there is an
abnormality.
3. The valve according to claim 1, wherein the abnormality
determination mechanism determines whether or not there is an
abnormality, according to whether or not a position of a top
surface or a bottom surface of the stem at the time of abnormality
diagnosis is a position of the top surface or the bottom surface at
the time of normality.
4. The valve according to claim 1, wherein the abnormality
determination mechanism determines whether or not there is an
abnormality, according to whether or not a stroke of the stem at
the time of abnormality diagnosis is matched with a stroke at the
time of normality.
5. The valve according to claim 1, wherein the abnormality
determination mechanism determines whether or not there is an
abnormality, according to whether or not an operating speed of the
stem at the time of abnormality diagnosis is matched with an
operating speed at the time of normality.
6. The valve according to any one of claim 1, wherein position
detection accuracy of the position sensor is .+-.0.01 mm to
.+-.0.001 mm.
7. An abnormality diagnosis method of a valve, the abnormality
diagnosis method comprising: a step comparing a change in a
distance between a predetermined location and a position sensor at
a time of abnormality diagnosis detected by the position sensor and
a previously measured change in the distance between the
predetermined location and the position sensor at a time of
normality, and determining whether or not there is an abnormality,
wherein the valve includes a stem sliding according to an
opening/closing operation of the valve, a pressing adapter pressing
a peripheral edge of a diaphragm, and the position sensor attached
to the pressing adapter and detecting the change in the distance
between the predetermined location of the stem and the position
sensor.
8. A non-transitory computer-readable storage medium storing a
program to cause a computer to execute processing for diagnosing an
abnormality of a valve comprising: comparing a change in a distance
between a predetermined location and a position sensor at a time of
abnormality diagnosis detected by the position sensor and a
previously measured change in the distance between the
predetermined location and the position sensor at a time of
normality, and determining whether or not there is an abnormality,
wherein the valve includes a stem sliding according to an
opening/closing operation of the valve, a pressing adapter pressing
a peripheral edge of a diaphragm, and the position sensor attached
to the pressing adapter and detecting the change in the distance
between the predetermined location of the stem and the position
sensor.
Description
TECHNICAL FIELD
[0001] The present invention relates to a valve capable of
diagnosing an abnormality and a method for diagnosing an
abnormality of the valve.
BACKGROUND ART
[0002] A fluid control device such as an automatic valve is used in
a fluid supply line that supplies a process fluid used in a
semiconductor manufacturing process.
[0003] In recent years, a semiconductor manufacturing process such
as atomic layer deposition (ALD) is advanced and complicated, and
the number of fluid control devices mounted on a gas unit
increases. Further, with the advancement of the fluid control
device, wiring around the fluid control device, such as electric
wiring and an air tube for supplying a drive pressure, is
complicated.
[0004] In this regard, Patent Literature 1 proposes a valve that
includes a body provided with a first flow passage and a second
flow passage and a valve element causing the first flow passage and
the second flow passage to communicate with or block each other.
The body has a base portion that has a first plane located at the
side of the valve element and a second plane located at the side
opposite to the first plane, a first connection portion that has a
third plane forming a step portion with the second plane, and a
second connection portion that has a fourth plane forming a step
portion with the first plane. The first flow passage has a 1-1 flow
passage and a 1-2 flow passage. A 1-1 port of the 1-1 flow passage
is opened to the third plane, a 1-3 port of the 1-2 flow passage
communicates with a 1-2 port of the 1-1 flow passage and is opened
to the valve element, a 1-4 port of the 1-2 flow passage is opened
to the fourth plane, and the first flow passage and the second flow
passage can communicate with each other via the 1-3 port. The first
connection portion is connected to a portion corresponding to the
second connection portion in a body of another valve, and the 1-1
flow passage and a flow passage corresponding to the 1-2 flow
passage in the body of another valve communicate with each
other.
[0005] Further, as technology for diagnosing an abnormality of the
valve, Patent Literature 2 proposes an orifice clogging detection
method in a pressure type flow rate control device. The flow rate
control device includes a control valve, an orifice, a pressure
detector for detecting an upstream side pressure between them, and
a flow rate setting circuit. The flow rate control device holds the
upstream side pressure at about twice or more a downstream side
pressure, calculates a flow rate of the downstream side, and
controls opening/closing of the control valve, on the basis of a
difference signal between the calculated flow rate and a setting
flow rate. The orifice clogging detection method includes a first
step of holding the setting flow rate at a high setting flow rate
of a 100% flow rate, a second step of switching the high setting
flow rate to a low setting flow rate of a 0% flow rate, holding the
low setting flow rate, and measuring the upstream side pressure to
obtain pressure attenuation data, a third step of comparing the
pressure attenuation data and reference pressure attenuation data
measured when the orifice has no clogging under the same
conditions, and a fourth step of reporting clogging when the
pressure attenuation data after a predetermined time elapses from
switching to the low setting flow rate is separated from the
reference pressure attenuation data by a predetermined degree or
more.
CITATION LIST
Patent Literature
Patent Literature 1: JP 2016-223533 A
Patent Literature 2: Japanese Patent No. 3546153
SUMMARY OF INVENTION
Technical Problem
[0006] Under the influence of the advanced and complicated
semiconductor manufacturing process, a load on the valve mounted on
the fluid supply line becomes severe, and the maintenance frequency
and the product life cycle are shortened. For this reason, there is
a need for a method that can accurately and simply determine an
operation abnormality of the valve.
[0007] Further, the complexity of electric wiring and an air tube
may cause an operation failure due to bending and torsion, and the
connection destination of the wiring may be confused, which is
inconvenient for maintenance or the like. Further, there is a need
for simplifying the wiring to secure electromagnetic performance
and realize noise reduction and response delay prevention. For this
reason, a function and a structure for determining the abnormal
operation of the valve should not cause complexity of the electric
wiring and the air tube in consideration of such circumstances
[0008] Accordingly, an object of the present invention is to enable
accurate and simple diagnosis of an operation abnormality of a
valve.
Solution to Problem
[0009] In order to achieve the above object, a valve according to
one aspect of the present invention is a valve capable of detecting
an operation abnormality. The valve has: a stem that slides
according to an opening/closing operation of the valve; a pressing
adapter that presses a peripheral edge of a diaphragm; a position
sensor that is attached to the pressing adapter and detects a
change in the distance between a predetermined location of the stem
and the position sensor; and an abnormality determination mechanism
that compares the change in the distance between the predetermined
location and the position sensor at the time of abnormality
diagnosis detected by the position sensor and a previously measured
change in the distance between the predetermined location and the
magnetic sensor at the time of normality, and determines whether or
not there is an abnormality.
[0010] The valve may further have a magnet that is attached to a
predetermined location in the vicinity of the pressing adapter. The
position sensor may be composed of a magnetic sensor that is
attached to a surface facing the stem, inside the pressing adapter,
and detects a change in the distance between the magnet and the
magnetic sensor, and the abnormality determination mechanism may
compare the change in the distance between the magnet and the
magnetic sensor at the time of abnormality diagnosis detected by
the magnetic sensor and a previously measured change in the
distance between the magnet and the magnetic sensor at the time of
normality, and may determine whether or not there is an
abnormality.
[0011] In addition, the abnormality determination mechanism may
determine whether or not there is an abnormality, according to
whether or not a position of a top surface or a bottom surface of
the stem at the time of abnormality diagnosis is a position of the
top surface or the bottom surface at the time of normality.
[0012] Further, the abnormality determination mechanism may
determine whether or not there is an abnormality, according to
whether or not a stroke of the stem at the time of abnormality
diagnosis is matched with a stroke at the time of normality.
[0013] Moreover, the abnormality determination mechanism may
determine whether or not there is an abnormality, according to
whether or not an operating speed of the stem at the time of
abnormality diagnosis is matched with an operating speed at the
time of normality.
[0014] Further, position detection accuracy of the position sensor
may be .+-.0.01 mm to .+-.0.001 mm.
[0015] An abnormality diagnosis method of a valve according to
another aspect of the present invention is an abnormality diagnosis
method of a valve including a stem that slides according to an
opening/closing operation of the valve, a pressing adapter that
presses a peripheral edge of a diaphragm, and a position sensor
that is attached to the pressing adapter and detects a change in
the distance between a predetermined location of the stem and the
position sensor. The abnormality diagnosis method has a step of
comparing the change in the distance between the predetermined
location and the position sensor at the time of abnormality
diagnosis detected by the position sensor and a previously measured
change in the distance between the predetermined location and the
position sensor at the time of normality, and determining whether
or not there is an abnormality.
[0016] A computer program according to another aspect of the
present invention is a computer program for diagnosing an
abnormality of a valve including a stem that slides according to an
opening/closing operation of the valve, a pressing adapter that
presses a peripheral edge of a diaphragm, and a position sensor
that is attached to the pressing adapter and detects a change in
the distance between a predetermined location of the stem and the
position sensor. The computer program causes a computer to execute
a process to compare the change in the distance between the
predetermined location and the position sensor at the time of
abnormality diagnosis detected by the position sensor and a
previously measured change in the distance between the
predetermined location and the position sensor at the time of
normality, and determining whether or not there is an
abnormality.
[0017] The computer program can be provided by being recorded on
various computer program-readable recording media.
Advantageous Effects of Invention
[0018] According to the present invention, an operation abnormality
of a valve can be diagnosed accurately and simply. Further, a fluid
supply line does not become complicated.
BRIEF DESCRIPTION OF DRAWINGS
[0019] FIG. 1 is a schematic view illustrating an internal
structure of a valve according to an embodiment of the present
invention.
[0020] FIG. 2 is an external perspective view illustrating a gas
unit configured by a fluid supply line including a valve according
to an embodiment of the present invention.
[0021] FIG. 3 is a plan view illustrating a gas unit configured by
a fluid supply line including a valve according to the present
embodiment.
[0022] FIG. 4 is a side view illustrating a gas unit configured by
a fluid supply line including a valve according to the present
embodiment.
[0023] FIG. 5 is a cross-sectional view illustrating an internal
structure of a valve according to the present embodiment, in which
(a) is an overall view and (b) is a partial enlarged view.
[0024] FIG. 6 is a functional diagram illustrating an example of a
functional configuration of a valve according to the present
embodiment.
[0025] FIG. 7 is a schematic diagram illustrating a wiring
structure of a cable in a gas unit configured by a fluid supply
line including a valve according to the present embodiment.
[0026] FIG. 8 is a schematic diagram illustrating a connection
structure of a drive pressure supply path in a gas unit configured
by a fluid supply line including a valve according to the present
embodiment.
[0027] FIG. 9 is a schematic diagram illustrating a connection
structure of a drive pressure supply path in a gas unit configured
by a fluid supply line according to a modification of the present
embodiment.
[0028] FIG. 10 is an external perspective view illustrating a gas
unit configured by a fluid supply line according to another
embodiment of the present invention.
[0029] FIG. 11 is a schematic diagram illustrating a wiring
structure of a cable in a gas unit configured by a fluid supply
line according to another embodiment of the present invention.
[0030] FIG. 12 is a schematic diagram illustrating a connection
structure of a drive pressure supply path in a gas unit configured
by a fluid supply line according to another embodiment of the
present invention.
[0031] FIG. 13 is a diagram illustrating a valve according to
another embodiment of the present invention, in which (a) is an
external perspective view and (b) is a plan view.
[0032] FIG. 14 is an A-A cross-sectional view illustrating an
internal structure of a valve according to another embodiment of
the present invention, in which (a) illustrates a valve closing
state and (b) illustrates a valve opening state.
[0033] FIG. 15 is a B-B cross-sectional view illustrating an
internal structure of a valve according to another embodiment of
the present invention, in which (a) illustrates a valve closing
state and (b) illustrates a valve opening state.
[0034] FIG. 16 is an exploded perspective view illustrating a fluid
control device configuring a fluid control apparatus according to
another embodiment of the present invention.
[0035] FIG. 17 is an exploded perspective view illustrating a fluid
control device configuring a fluid control apparatus according to
another embodiment of the present invention.
[0036] FIG. 18 is an exploded perspective view illustrating a fluid
control device configuring a fluid control apparatus according to
another embodiment of the present invention.
DESCRIPTION OF EMBODIMENTS
[0037] Valve V1
[0038] Hereinafter, a valve according to an embodiment of the
present invention and an abnormality diagnosis method of the valve
will be described.
[0039] As illustrated in FIG. 1, a valve V1 according to the
present embodiment includes a valve body 3 and a drive pressure
control device 4 connected to the valve body 3.
[0040] The valve body 3 is a valve used in a gas line of a fluid
control apparatus, such as a diaphragm valve, and includes at least
a drive pressure introduction port 3a for introducing a drive
pressure supplied from an outside to an inside.
[0041] The drive pressure control device 4 is connected to the
drive pressure introduction port 3a of the valve body 3, and
supplies a drive pressure supplied from a drive pressure supply
source G to the valve body 3.
[0042] The drive pressure control device 4 includes drive pressure
introduction paths 431, 432, and 433 as introduction paths for
introducing the drive pressure from the drive pressure supply
source G outside the line to the valve body 3. The drive pressure
introduction path 431 is connected to the drive pressure supply
source G outside the line. The drive pressure introduction path 432
connects the drive pressure introduction path 431 and the drive
pressure introduction path 433 via an automatic valve 411 and an
automatic valve 412. The drive pressure introduction path 433 is
connected to the drive pressure introduction port 3a of the valve
body 3.
[0043] Further, the drive pressure control device 4 is provided
with a normally closed (N.C.) automatic valve 411 that opens and
closes the drive pressure introduction path 431, and a normally
opened (N.O.) automatic valve 412 that opens and closes the drive
pressure introduction path 433 in conjunction with the automatic
valve 411 and opens and closes an exhaust passage 44 for exhausting
the drive pressure from the drive pressure introduction path 433 to
the outside A of the device.
[0044] The automatic valves 411 and 412 are opened and closed by
valve drive units 421 and 422, respectively. The valve drive units
421 and 422 receive power and an instruction signal for instructing
an operation from a power supply source E and an instruction signal
transmission source Q via wiring 45, and execute an operation based
on the instruction signal.
[0045] Both the automatic valves 411 and 412 can be configured by
various valves such as a normal solenoid valve, an air-operated
solenoid valve, or an electric valve.
[0046] In the drive pressure control device 4, the automatic valves
411 and 412, the valve drive units 421 and 422, the drive pressure
introduction paths 431, 432, and 433, and the like are covered with
a hollow cap-shaped casing 40, and the valve body 3 is covered with
the casing 40 so as to be integrated with the valve body 3.
[0047] The valve body 3 and the casing 40 can be appropriately
integrated by a mechanism such as screwing or bonding with an
adhesive.
[0048] In the drive pressure control device 4 having the above
configuration, regardless of the opening/closing state of the
automatic valves 411 and 412, the drive pressure supplied from the
drive pressure supply source G outside the line is always supplied
to a place of the automatic valve 411 via the drive pressure
introduction path 431.
[0049] The opening/closing operation of the drive pressure control
device 4 will be described. First, when the automatic valve 411 is
opened by the valve drive unit 421, the drive pressure supplied to
the automatic valve 411 is led to the automatic valve 412 via the
drive pressure introduction path 432. Further, the automatic valve
412 is interlocked with the automatic valve 411, and is closed when
the automatic valve 411 is opened, the exhaust passage 44 is
closed, and the drive pressure is supplied to the valve body 3 via
the drive pressure introduction path 433.
[0050] On the other hand, when the automatic valve 411 is closed by
the valve drive unit 421, the drive pressure supplied from the
drive pressure supply source G is blocked by the automatic valve
411. Further, the automatic valve 412 interlocked with the
automatic valve 411 is opened, the exhaust passage 44 is opened,
and the drive pressure in the valve body 3 is exhausted.
[0051] According to the valve V1 of the present embodiment, since
the drive pressure control device 4 and the valve body 3 are
integrally connected, wiring connected to the valve V1 can be
simplified.
[0052] Further, the drive pressure is always supplied to a place of
the automatic valve 411 of the drive pressure control device 4
integrally connected to the valve body 3, and a state where the
drive pressure is increased to a constant pressure in a place close
to the drive pressure introduction port 3a of the valve body 3 is
maintained. As a result, the valve body 3 is less susceptible to a
change in the drive pressure at the time of opening/closing, the
opening/closing speed can be maintained constantly, and accuracy of
controlling material gas can be improved.
[0053] Although the valve V1 described above has the structure in
which the drive pressure control device 4 is connected to the valve
body 3, the present invention is not limited thereto. A space for
incorporating the drive pressure control device 4 is secured in the
valve body 3, so that the drive pressure control device 4 can be
incorporated in the space.
[0054] Next, a fluid supply line configured by the above-described
valve V1 will be described.
[0055] As illustrated in FIGS. 2 to 4, a gas unit 1 includes three
fluid supply lines L1, L2, and L3 according to the present
embodiment.
[0056] Here, the "fluid supply lines (L1, L2, and L3)" are one of
constituent units of the gas unit (1), and include a path through
which a process fluid circulates and a group of fluid control
devices arranged on the path. The fluid supply lines (L1, L2, and
L3) are minimum constituent units that can control the process
fluid and independently process a processed object. The gas unit is
normally configured by arranging a plurality of fluid supply lines
in parallel. Further, "outside the line" mentioned in the following
description is a portion or mechanism that does not configure the
fluid supply line, and a mechanism outside the line includes a
power supply source for supplying power required for driving the
fluid supply line, a drive pressure supply source for supplying a
drive pressure, a device configured to be able to communicate with
the fluid supply line, and the like.
[0057] Each of the fluid supply lines L1, L2, and L3 causes a
plurality of fluid control devices to communicate with each other
fluid-tightly, and the fluid control devices include valves (V11 to
V14, V21 to V24, and V31 to V34) each including the above-described
valve V1 and flow rate control devices (F1 to F3). In the following
description, the valves (V11 to V14, V21 to V24, and V31 to V34)
may be collectively referred to as the valve V1, and the flow rate
control devices (F1 to F3) may be collectively referred to as the
flow rate control device F.
[0058] The flow rate control device F is a device that controls a
flow rate of a fluid in each of the fluid supply lines L1, L2, and
L3.
[0059] The flow rate control device F can be configured by a flow
rate range variable type flow rate control device, for example. The
flow rate range variable type flow rate control device is a device
that can automatically switch and select a flow rate control region
by operating a switching valve.
[0060] The flow rate range variable type flow rate control device
has, for example, a fluid passage for a small flow rate and a fluid
passage for a large flow rate as a fluid passage to a flow rate
detection unit of the flow rate control device. A fluid in a small
flow rate region is circulated to the flow rate detection unit
through the fluid passage for the small flow rate and a detection
level of the flow rate control unit is switched to a detection
level suitable for the detection of the small flow rate region, and
a fluid in a large flow rate region is circulated to the flow rate
detection unit through the fluid passage for the large flow rate
and the detection level of the flow rate control unit is switched
to a detection level suitable for the detection of the flow rate of
the large flow rate region. As a result, the flow rate is
controlled by switching the fluid in each of the large flow rate
region and the small flow rate region.
[0061] Further, the flow rate range variable type flow rate control
device is a pressure type flow rate control device in which a flow
rate of a fluid circulating through an orifice is calculated as
Qc=KP.sub.1 (K is a proportional constant) or
Qc=KP.sub.2.sup.m(P.sub.1-P.sub.2).sup.n (K is a proportional
constant and m and n are constants) by using an orifice upstream
side pressure P.sub.1 and/or an orifice downstream side pressure
P.sub.2. A fluid passage between the downstream side of a control
valve of the pressure type flow rate control device and a fluid
supply pipeline can be configured as at least two or more parallel
fluid passages, and an orifice with a different fluid flow rate
characteristic can be interposed in each parallel fluid passage. In
this case, the fluid in the small flow rate region is circulated to
one orifice for flow rate control of the fluid in the small flow
rate region, and the fluid in the large flow rate region is
circulated to at least the other orifice for flow rate control of
the fluid in the large flow rate region.
[0062] Further, a range of the flow rate can be set in three
stages. In this case, the orifices are set as three types of
orifices including a large flow rate orifice, an intermediate flow
rate orifice, and a small flow rate orifice. Further, a first
switching valve, a second switching valve, and the large flow rate
orifice are interposed in series in one fluid passage, the small
flow rate orifice and the intermediate flow rate orifice are
interposed in the other fluid passage, and a passage communicating
between the two switching valves and a passage communicating
between the small flow rate orifice and the intermediate flow rate
orifice are caused to communicate with each other.
[0063] According to the flow rate range variable type flow rate
control device, it is possible to maintain high control accuracy
while expanding a flow rate control range.
[0064] Further, in another example, the flow rate control device F
can be configured by a differential pressure type flow rate control
device. The differential pressure type flow rate control device is
a device that uses a flow rate calculation formula derived from
Bernoulli's theorem as a basis and calculates and controls a fluid
flow rate by adding various corrections thereto.
[0065] The differential pressure type flow rate control device has
a control valve including a valve drive unit, an orifice provided
on the downstream side of the control valve, a detector for a fluid
pressure P.sub.1 of the upstream side of the orifice, a detector
for a fluid pressure P.sub.2 of the downstream side of the orifice,
and a detector for a fluid temperature T of the upstream side of
the orifice. By using an incorporated control arithmetic circuit, a
fluid flow rate Q is calculated by Q=C.sub.1P.sub.1/
T((P.sub.2/P.sub.1)m-(P.sub.2/P.sub.1).sub.n).sup.1/2 (where
C.sub.1 is a proportional constant, and m and n are constants)
using a detection pressure and a detection temperature from each
detector, and a difference between the calculated flow rate and the
setting flow rate is calculated.
[0066] According to the differential pressure type flow rate
control device, it can be used in an in-line form without
restrictions on a mounting posture. Further, a control flow rate is
hardly affected by a variation in the pressure, and highly accurate
flow rate measurement or flow rate control can be performed in real
time.
[0067] The flow rate control device F includes an operation
information acquisition mechanism that acquires operation
information of the flow rate control device F, and an information
processing module that collects operation information of the valves
V1 forming the same line, monitors the valves V1, and controls each
valve V1.
[0068] The operation information acquisition mechanism can include,
for example, various sensors incorporated in the flow rate control
device F, arithmetic devices for performing the flow rate control,
an information processing module for executing processing of
information of the sensors and the arithmetic devices, and the
like.
[0069] In particular, with respect to the valves V1 configuring the
same fluid supply lines L1, L2, and L3, by supplying a drive
pressure from a mechanism outside the line via the flow rate
control device F or enabling communication, the operation
information of each valve V1 can be collected in the flow rate
control device F. As a result, operation information of the entire
line is configured together with the operation information of each
valve V1 and the operation information of the flow rate control
device F.
[0070] The valve V1 has the above-described configuration as an
operation mechanism, and as a function or a mechanism capable of
detecting its own operation abnormality, an operation information
acquisition mechanism that acquires operation information of the
valve V1 and an information processing module for processing data
detected by the operation information acquisition mechanism are
incorporated in the valve V1.
[0071] FIG. 5 illustrates an example of a specific configuration of
the valve V1.
[0072] The valve V1 has a magnetic sensor M2 and a magnet M1 as the
operation information acquisition mechanism. The magnetic sensor M2
is attached to a surface facing a stem 53, inside of a pressing
adapter 52 that presses a peripheral edge of a diaphragm 51.
Further, the magnet M1 is attached in the vicinity of the pressing
adapter 52 of the stem 53 that slides according to the
opening/closing operation of the valve V1.
[0073] The magnetic sensor M2 can measure not only an
opening/closing state but also an opening degree of the valve V1 by
sensing a change in the distance from the magnet M1 attached to a
predetermined position.
[0074] A cable or the like for transmitting and receiving measured
data may be connected to the magnetic sensor M2, while the magnet
M1 does not require such a wired connection. Therefore, by
attaching the magnet M1 to the stem 53 moving vertically and
attaching the magnetic sensor M2 to the pressing adapter 52 whose
position is fixed in the valve V1, the cable connected to the
magnetic sensor M2 moves with the operation of the valve V1, and it
is possible to prevent a situation that causes an operation
failure.
[0075] Here, the magnetic sensor M2 has a planar coil, an
oscillation circuit, and an integration circuit, and an oscillation
frequency changes according to a change in the distance from the
magnet M1 located at the facing position. In addition, by
converting the frequency by the integration circuit and obtaining
an integrated value, not only the opening/closing state of the
valve V1 but also the opening degree at the time of opening the
valve can be measured.
[0076] Further, as illustrated in FIG. 6, the information
processing module incorporated in the valve V1 has an abnormality
determination unit as a functional unit that determines whether or
not there is an abnormality in the valve V1, on the basis of the
data acquired by the magnetic sensor M2. The abnormality
determination unit compares a change in the distance between the
magnet M1 and the magnetic sensor M2 detected by the magnetic
sensor M2 and a previously measured change in the distance between
the magnet M1 and the magnetic sensor M2 at the time of normality
and determines whether or not there is an abnormality.
[0077] Abnormality Determination Unit
[0078] Here, processing that can be executed by the abnormality
determination unit will be described.
[0079] First, the abnormality determination unit can determine the
presence or absence of an abnormality according to whether or not a
top surface or bottom surface position of the stem 53 at the time
of abnormality diagnosis is a top surface or bottom surface
position at the time of normality. That is, the top surface
position and the bottom surface position when the stem 53 is
operated are measured on the basis of a change in the distance
between the magnetic sensor M2 and the magnet M1. It is determined
whether or not the top surface position and the bottom surface
position are matched with the previously measured top surface
position and bottom surface position at the time of normality. If
they are matched, it can be determined that there is no
abnormality, and if they are not matched, it can be determined that
there is an abnormality.
[0080] Further, the abnormality determination unit can determine
the presence or absence of the abnormality according to whether or
not the stroke of the stem 53 at the time of abnormality diagnosis
is matched with the stroke at the time of normality. That is, a
movement distance (stroke) from the top surface position to the
bottom surface position when the stem 53 is operated is measured on
the basis of the change in the distance between the magnetic sensor
M2 and the magnet M1. It is determined whether or not the stroke is
matched with the previously measured stroke at the time of
normality. If they are matched, it can be determined that there is
no abnormality, and if they are not matched, it can be determined
that there is an abnormality.
[0081] Further, the abnormality determination unit can determine
the presence or absence of the abnormality according to whether or
not the operating speed of the stem 53 at the time of abnormality
diagnosis is matched with the operating speed at the time of
normality. That is, the operating speed at the time of operating
the stem 53 is measured on the basis of a change in the distance
between the magnetic sensor M2 and the magnet M1. It is determined
whether or not the operating speed is matched with the previously
measured operating speed at the time of normality. If they are
matched, it can be determined that there is no abnormality, and if
they are not matched, it can be determined that there is an
abnormality.
[0082] According to the configuration of the valve V1 and the
abnormality diagnosis method thereof, it is possible to accurately
and simply diagnose an operation abnormality of the valve V1.
Further, since the abnormality diagnosis mechanism is integrated in
the valve V1, the gas unit 1 does not become complicated. As a
result, the electric wiring and the air tube do not become
complicated and do not cause an operation failure due to bending or
twisting, and satisfy requirements such as securing electromagnetic
performance, reducing noise, and preventing response delay.
[0083] In the above-described example, although the valve V1
includes the information processing module configuring the
abnormality determination unit, the present invention is not
limited thereto. A server or the like provided outside the valve V1
or outside the fluid supply lines L1, L2, and L3 may be provided
with the functions provided in the information processing module.
In this case, it is possible to confirm an operation abnormality of
each valve V1 while integrally monitoring the plurality of valves
V1 configuring the fluid supply lines L1, L2, and L3.
[0084] Further, as the operation information acquisition mechanism,
in addition to the magnetic sensor M2 described above, a pressure
sensor, a temperature sensor, a limit switch, and the like may be
appropriately attached to predetermined locations. The pressure
sensor is configured by, for example, a pressure-sensitive element
for detecting a pressure change in a predetermined space, a
piezoelectric element for converting a detection value of a
pressure detected by the pressure-sensitive element into an
electric signal, and the like, and detects a pressure change in the
sealed internal space.
[0085] Further, the temperature sensor is, for example, a sensor
for measuring the temperature of the fluid. The temperature sensor
is installed in the vicinity of the flow passage to measure the
temperature of the corresponding location, so that the temperature
of the installation location can be regarded as the temperature of
the fluid circulating through the flow passage.
[0086] Further, the limit switch is fixed in the vicinity of a
piston, for example, and the switch is switched according to a
vertical movement of the piston. As a result, the number of times
of opening/closing the valve V1, the frequency of opening/closing
thereof, the opening/closing speed thereof, and the like can be
detected.
[0087] The information acquired by the operation information
acquisition mechanism in the valve V1 and the information processed
by the information processing module can be collected in the flow
rate control devices F configuring the same fluid supply lines L1,
L2, and L3.
[0088] The gas unit 1 is connected to a mechanism outside the line
including a drive pressure supply source that supplies a drive
pressure, a power supply source that supplies power, a
communication device that performs communication, and the like.
[0089] Here, the fluid control device configuring the gas unit 1 is
connected by a first connection mechanism that directly connects
the mechanism outside the line and the predetermined fluid control
device, and a second connection mechanism that branches from the
first connection mechanism or uses the fluid control device
connected by the first connection mechanism and connects the
mechanism outside the line and another fluid control device.
Specifically, in the case of the fluid supply line L1, in FIG. 7
which will be described in detail later, in the power supply from
the outside of the line and the communication with the outside of
the line, a main cable 10 and an extension cable 11 configure the
first connection mechanism, and sub-cables 111, 112, 113, and 114
configure the second connection mechanism. Further, in FIG. 8 which
will be described in detail later, in the supply of the drive
pressure from the outside of the line, a main tube 20, an extension
tube 21, and a sub-tube 214 configure the first connection
mechanism, and extension tubes 211, 212, and 213 and sub-tubes 215,
216, 217, and 218 configure the second connection mechanism.
[0090] As illustrated in FIG. 7, the power supply and the
communication with the outside of the line are enabled by the main
cable 10 that connects the mechanism outside the line and the gas
unit 1.
[0091] The main cable 10 branches into an extension cable 11 and a
branch cable 101 by a branch connector C1 provided in the vicinity
of the gas unit, the branch cable 101 branches into an extension
cable 12 and a branch cable 102 by a branch connector C2, and the
branch cable 102 is connected to an extension cable 13 via a branch
connector C3.
[0092] Looking at each of the fluid supply lines L1, L2, and L3, in
the fluid supply line L1, the extension cable 11 is connected to
the flow rate control device F1. The sub-cables 111 and 112 are led
out from the flow rate control device F1 to which the extension
cable 11 is connected, the sub-cable 111 is connected to the valve
V11, and the sub-cable 112 is connected to the valve V12.
[0093] Further, the sub-cable 113 is led out from the valve V12 to
which the sub-cable 112 is connected, and the sub-cable 113 is
connected to the valve V13. Further, the sub-cable 114 is led out
from the valve V13 to which the sub-cable 113 is connected, and the
sub-cable 114 is connected to the valve V14.
[0094] The fluid supply line L2 is also connected to the mechanism
outside the line by the same configuration as that of the fluid
supply line L1.
[0095] That is, the extension cable 12 is connected to the flow
rate control device F2. The sub-cables 121 and 122 are led out from
the flow rate control device F2 to which the extension cable 12 is
connected, the sub-cable 121 is connected to the valve V21, and the
sub-cable 122 is connected to the valve V22.
[0096] In addition, the sub-cable 123 is led out from the valve V22
to which the sub-cable 122 is connected, and the sub-cable 123 is
connected to the valve V23. Further, the sub-cable 124 is led out
from the valve V23 to which the sub-cable 123 is connected, and the
sub-cable 124 is connected to the valve V24.
[0097] The fluid supply line L3 is also connected to the mechanism
outside the line by the same configuration as that of the fluid
supply line L1.
[0098] That is, the extension cable 13 is connected to the flow
rate control device F3. The sub-cables 131 and 132 are led out from
the flow rate control device F3 to which the extension cable 13 is
connected, the sub-cable 131 is connected to the valve V31, and the
sub-cable 132 is connected to the valve V32.
[0099] In addition, the sub-cable 133 is led out from the valve V32
to which the sub-cable 132 is connected, and the sub-cable 133 is
connected to the valve V33. Further, the sub-cable 134 is led out
from the valve V33 to which the sub-cable 133 is connected, and the
sub-cable 134 is connected to the valve V34.
[0100] Here, for the fluid supply line L1, the extension cable 11
is connected to the flow rate control device F1, and the sub-cables
111 and 112 are led out from the flow rate control device F1.
However, in the flow rate control device F1, the extension cable 11
and the sub-cables 111 and 112 are connected. The connection can be
made by using the information processing module provided in the
flow rate control device F1 or branching the extension cable
11.
[0101] Even in the valves V12 and V13, the sub-cable 112 is
connected to the sub-cable 113, and the sub-cable 113 is connected
to the sub-cable 114. The connection of the sub-cables 112, 113,
and 114 can also be made by using information processing modules
provided in the valves V12 and V13 or branching the sub-cables 112
and 113.
[0102] For any connection, the mechanism outside the line and the
valves V11, V12, V13, and V14 may be communicably connected via the
flow rate control device F1 and power may be supplied.
[0103] The same is applied to connections in the other fluid supply
lines L2 and L3, and the valves V21, V22, V23, and V24 are
connected to the mechanism outside the line via the flow rate
control device F2 by the main cable 10, the extension cable 12, and
the sub-cables 121, 122, 123, and 124. Further, the valves V31,
V32, V33, and V34 are connected to the mechanism outside the line
via the flow rate control device F3 by the main cable 10, the
extension cable 13, and the sub-cables 131, 132, 133, and 134.
[0104] As illustrated in FIG. 8, the drive pressure is supplied
from the mechanism outside the line to the gas unit by the main
tube 20.
[0105] The main tube 20 branches into extension tubes 21, 22, and
23 for respectively supplying the drive pressure to the fluid
supply lines L1, L2, and L3 by a branch joint J1 provided in the
vicinity of the gas unit.
[0106] Looking at each of the fluid supply lines L1, L2, and L3, in
the fluid supply line L1, the extension tube 21 is branched into
the extension tube 211 and the sub-tube 214 by a joint J11. The
sub-tube 214 is connected to the flow rate control device F1, so
that the drive pressure is supplied to the flow rate control device
F1.
[0107] The extension tube 211 is further branched into the
extension tube 212 and the sub-tube 215 by a joint J111. The
sub-tube 215 is connected to the valve V11, so that the drive
pressure is supplied to the valve V11.
[0108] Similarly, the extension tube 212 is further branched into
the extension tube 213 and the sub-tube 216 by a joint J112. The
sub-tube 216 is connected to the valve V12, so that the drive
pressure is supplied to the valve V12.
[0109] Further, the extension tube 213 is further branched into a
sub-tube 217 and a sub-tube 218 by a joint J113. The sub-tube 217
is connected to the valve V13, so that the drive pressure is
supplied to the valve V13. Further, the sub-tube 218 is connected
to the valve V14, so that the drive pressure is supplied to the
valve V14.
[0110] The drive pressure is also supplied to the fluid supply line
L2 by the same configuration as that of the fluid supply line
L1.
[0111] That is, the extension tube 22 is branched into an extension
tube 221 and a sub-tube 224 by a joint J12. The sub-tube 224 is
connected to the flow rate control device F2, so that the drive
pressure is supplied to the flow rate control device F2.
[0112] The extension tube 221 is further branched into an extension
tube 222 and a sub-tube 225 by a joint J121. The sub-tube 225 is
connected to the valve V21, so that the drive pressure is supplied
to the valve V21.
[0113] Similarly, the extension tube 222 is further branched into
an extension tube 223 and a sub-tube 226 by a joint J122. The
sub-tube 226 is connected to the valve V22, so that the drive
pressure is supplied to the valve V22.
[0114] Further, the extension tube 223 is further branched into a
sub-tube 227 and a sub-tube 228 by a joint J123. The sub-tube 227
is connected to the valve V23, so that the drive pressure is
supplied to the valve V23. Further, the sub-tube 228 is connected
to the valve V24, so that the drive pressure is supplied to the
valve V24.
[0115] The drive pressure is also supplied to the fluid supply line
L3 by the same configuration as that of the fluid supply line
L1.
[0116] That is, the extension tube 23 is branched into an extension
tube 231 and a sub-tube 234 by a joint J13. The sub-tube 234 is
connected to the flow rate control device F3, so that the drive
pressure is supplied to the flow rate control device F3.
[0117] The extension tube 231 is further branched into an extension
tube 232 and a sub-tube 235 by a joint J131. The sub-tube 235 is
connected to the valve V31, so that the drive pressure is supplied
to the valve V31.
[0118] Similarly, the extension tube 232 is further branched into
an extension tube 233 and a sub-tube 236 by a joint J132. The
sub-tube 236 is connected to the valve V32, so that the drive
pressure is supplied to the valve V32.
[0119] Further, the extension tube 233 is further branched into a
sub-tube 237 and a sub-tube 238 by a joint J133. The sub-tube 237
is connected to the valve V33, so that the drive pressure is
supplied to the valve V33. Further, the sub-tube 238 is connected
to the valve V34, so that the drive pressure is supplied to the
valve V34.
[0120] Here, for the fluid supply line L1, the flow rate control
device F1 and the valves V11, V12, V13, and V14 are connected to
the extension tube 21 and the main tube 20 in front of the
extension tube 21 via the joints J11, J111, J112, and J113, the
extension tubes 211, 212, and 213, and the sub-tubes 214, 215, 216,
217, and 218. However, the present invention is not limited
thereto. As illustrated in FIG. 9, after connecting the extension
tube 21 and the flow rate control device F1, the drive pressure can
be supplied from the flow rate control device F1 to each of the
valves V11, V12, V13, and V14. In this case, a mechanism for
distributing the drive pressure supplied from the main tube 20 to
the valves V11, V12, V13, and V14 may be provided in the flow rate
control device F1, or the main tube drawn into the flow rate
control device F1 may be branched in the flow rate control device
F1.
[0121] The same can be applied to the fluid supply lines L2 and
L3.
[0122] According to the configurations of the fluid supply lines
L1, L2, and L3, the cable for performing the power supply or the
communication is simplified, noise can be reduced, and delay in the
transmission speed of the instruction signal can be suppressed.
Further, since the inner volume of the tube supplying the drive
pressure can be reduced, the opening/closing speed of each fluid
control device such as the valve V1 and the flow rate control
device F can be maintained, and an error can be prevented from
occurring in the opening/closing speed of each fluid control
device. As a result, it is possible to improve control accuracy of
the fluid supply lines L1, L2, and L3 by suppressing a variation in
the operation of each of the fluid control devices.
[0123] Further, in this case, each valve V1 is communicably
connected to the flow rate control device F. If the flow rate
control device F can identify and control each valve V1, each valve
V1 configuring the same line can be individually identified to
diagnose the presence or absence of an abnormality, or the
operation of each valve V1 viewed from the entire line can be
analyzed.
[0124] The operation information of the fluid supply lines L1, L2,
and L3 collected in the flow rate control devices F1, F2, and F3
can be transmitted to an external information processing device via
the main cable 10 to diagnose the presence or absence of the
abnormality or analyze the operation in the information processing
device. The external information processing device may configure a
part of the mechanism outside the line, or may be a device
connected to be communicable with the mechanism outside the line.
Further, the external information processing device can be
configured by a so-called server computer or the like.
[0125] The fluid supply lines L1, L2, and L3 described above can
also configure a gas unit 2 illustrated in FIGS. 10 to 12.
[0126] Unlike the gas unit 1, the fluid supply lines L1, L2, and L3
configuring the gas unit 2 are individually connected to the
mechanism outside the line.
[0127] That is, as illustrated in FIG. 11, power supply to the gas
unit 2 and communication between the gas unit 2 and the outside of
the line can be performed by a main cable 10a connecting the
mechanism outside the line and the fluid supply line L1, a main
cable 10b connecting the mechanism outside the line and the fluid
supply line L2, and a main cable 10c connecting the mechanism
outside the line and the fluid supply line L3.
[0128] In each of the fluid supply lines L1, L2, and L3, connection
from the flow rate control device F to the valve V1 is the same as
that of the gas unit 1.
[0129] Further, as illustrated in FIG. 12, the drive pressure is
supplied from the mechanism outside the line to the gas unit 2 by
main tubes 20a, 20b, and 20c for the fluid supply lines L1, L2, and
L3.
[0130] In each of the fluid supply lines L1, L2, and L3,
connections from the joints J11, J12, and J13 to the flow rate
control device F or the valve V1 are the same as those of the gas
unit 1.
[0131] In the above-described embodiment, each of the gas units 1
and 2 is configured by the three fluid supply lines L1, L2, and L3.
However, an application of the present invention is not limited by
the number of lines.
[0132] Further, the embodiments of the present invention are not
limited to the above-described embodiments, and those skilled in
the art can change or add various configurations, mechanisms, or
functions without departing from the scope of the present
invention.
[0133] Further, in the present embodiment, although the magnetic
sensor M2 is used, the present invention is not limited thereto.
Other types of sensors such as an optical position sensor can be
used as long as the position sensor can measure a position relation
between the stem 53 and the pressing adapter 52 or a distance
between predetermined locations of these members.
[0134] Further, even when any position sensor is used, it is
desirable to select a position sensor whose position detection
accuracy falls within a range of .+-.0.01 mm to .+-.0.001 mm. The
reason is as follows. As a valve for the semiconductor
manufacturing process, fine opening degree control of about
.+-.0.01 mm is required to realize fine fluid control, but if
detection accuracy exceeding .+-.0.001 mm is used, a vibration
generated by a vacuum pump or the like in the vicinity of the valve
V1 is detected and noise is generated.
[0135] Valve V2
[0136] A valve V2 according to another embodiment having a
structure different from that of the valve V1 according to the
present embodiment will be described with reference to FIGS. 13 to
18.
[0137] The valve V2 illustrated in FIG. 13 is an air-operated
direct diaphragm valve, and includes a valve body 6, a bonnet
portion 7, a cover portion 8, and an actuator portion 9, as
illustrated in FIGS. 14 to 16.
[0138] As illustrated in FIGS. 14 to 16, the valve body 6 includes
a base portion 61 that is provided with a flow passage and a
cylindrical portion 62 with a substantially cylindrical shape that
is provided on the base portion 61.
[0139] The base portion 61 has a rectangular shape in plan view,
and is a portion installed on a substrate or a manifold block when
the above-described gas unit 1 (2) is configured by a plurality of
valves V2.
[0140] The cylindrical portion 62 has a hollow shape with an opened
end face on the side where the bonnet portion 7 is disposed, and a
hollow interior configures a concave portion 62a in which the
bonnet portion 7 is accommodated.
[0141] The cylindrical portion 62 is provided with a slit 62b that
has a length in an axial direction, has an opening at one end on
the side opposite to the base portion 61 to be the side where the
bonnet portion 7 is disposed, and penetrates the cylindrical
portion 62 from the outside to the side of the concave portion 62a.
Through the slit 62b, a flexible cable 76 extending from a bonnet
wall 75 is led from the inside to the outside.
[0142] Below the concave portion 62a and in the base portion 61, an
inflow path 611 where the fluid flows in, an outflow path 613 where
the fluid flows out, and a valve chamber 712 communicating with the
inflow path 611 and the outflow path 613 are formed. The inflow
path 611, the outflow path 613, and the valve chamber 712
integrally configure a flow passage through which the fluid
circulates.
[0143] As illustrated in FIGS. 14 to 17, the bonnet portion 7 is
disposed so as to be accommodated in the concave portion 62a of the
valve body 6. The bonnet portion 7 includes a seat 71, a diaphragm
72, a diaphragm presser 73, a bonnet 74, and a bonnet wall 75.
[0144] The bonnet 74 in the present example is a member that
presses a peripheral edge of the diaphragm 72 from the top surface
side together with the bonnet wall 75 disposed in the bonnet 74,
and is a member that corresponds to the pressing adapter 52 in the
valve V1 described above. Further, in the present example, what is
referred to as the diaphragm presser 73 has a function of pressing
the diaphragm 72, similarly to the stem 53 in the valve V1.
[0145] The annular seat 71 is provided in a peripheral edge of an
opening of the inflow path 611 in the valve chamber 712. By
bringing the diaphragm 72 into and out of contact with the seat 71,
the fluid can be circulated from the inflow path 611 to the outflow
path 613, or the circulation can be blocked.
[0146] The diaphragm 72 is a spherical shell-shaped member that is
made of a metal such as stainless steel or a Ni--Co alloy and has a
center portion bulged in a convex shape, and it separates a flow
passage from an operation space of the actuator portion 9. In a
state where the diaphragm 72 is not pressed by the diaphragm
presser 73, as illustrated in FIGS. 14(b) and 15(b), the diaphragm
72 is separated from the seat 71, and the inflow path 611 and the
outflow path 613 communicate with each other. On the other hand, in
a state where the diaphragm 72 is pressed by the diaphragm presser
73, as illustrated in FIGS. 14(a) and 15(a), the center portion of
the diaphragm 72 deforms and comes into contact with the seat 71,
and the inflow path 611 and the outflow path 613 are blocked.
[0147] The diaphragm presser 73 is provided above the diaphragm 72,
and presses the center portion of the diaphragm 72 in conjunction
with a vertical movement of a piston 93.
[0148] The diaphragm presser 73 includes a substantially columnar
base portion 731 and a diameter expansion portion 732 having an
expanded diameter at one end on the side that comes into contact
with the diaphragm 72.
[0149] The base portion 731 is provided with a bottomed groove 731a
that has a length in an axial direction and has an opening at one
end on the side opposite to the diameter expansion portion 732. A
shaft rod portion of a screw 75d screwed into a screw hole 75c of
the bonnet wall 75 is slidably fitted into the groove 731a. The
groove 731a and the screw 75d configure a rotation regulation
mechanism for regulating the rotation of the diaphragm presser 73
in a circumferential direction. Thereby, the rotation of the
diaphragm presser 73 in the circumferential direction is regulated
while the diaphragm presser 73 moves vertically in conjunction with
the piston 93.
[0150] Further, a magnet M3 is attached to the base portion 731. In
the present embodiment, the magnet M3 is mounted on the side
opposite to the groove 731a of the base portion 731. However, as
long as there is no problem with a magnetic sensor M4 detecting the
magnetic force of the magnet M3 and there is no problem with the
operation of the valve V2, the magnet M3 can be mounted at another
position on the base portion 731.
[0151] The bonnet 74 has a substantially cylindrical shape, and is
accommodated in the concave portion 62a of the valve body 6.
[0152] The diaphragm 72 is sandwiched between a lower end of the
bonnet 74 and the valve body 6, and a seal between the diaphragm 72
and the valve body 6 is formed at this portion.
[0153] The bonnet 74 is provided with a substantially disk-shaped
partition portion 741 in which a through-hole 741a through which
the diaphragm presser 73 is inserted is formed in a center
portion.
[0154] The bonnet wall 75 is accommodated in the concave portion
74a formed above the partition portion 741 or on the side where the
actuator portion 9 is provided. The partition portion 741 and the
bonnet wall 75 are provided with screw holes 741b and through-holes
75e at positions corresponding to each other, and the bonnet wall
75 is screwed into the bonnet 74 with bolts 75f.
[0155] The partition portion 741 of the bonnet 74 has a certain
thickness, and an O-ring O7 is interposed between an inner
peripheral surface of the through-hole 741a formed in the partition
portion 741 and the diaphragm presser 73. Thereby, airtightness of
a closed space S2 defined by the partition portion 741, the
diaphragm 72, and the diaphragm presser 73 is secured.
[0156] Further, the partition portion 741 of the bonnet 74 is
provided with a communication hole 741d communicating with the
pressure sensor P attached to the bonnet wall 75. The pressure
sensor P is provided through the communication hole 741d, so that a
pressure in the closed space S2 defined by the partition portion
741, the diaphragm 72, and the diaphragm presser can be
measured.
[0157] Further, a side surface of the bonnet 74 is provided with a
through-hole 741c for leading out the flexible cable 76 from the
bonnet wall 75 accommodated inside.
[0158] The bonnet wall 75 is a member disposed in the bonnet 74.
The bonnet wall 75 is formed by hollowing a substantially
disk-shaped member having a large thickness into a substantially
C-shape in plan view. At the center of the bonnet wall 75, a
through-hole 75a through which the base portion 731 of the
diaphragm presser 73 is inserted is provided. Further, an opening
75b that opens the through-hole 75a outward in a radial direction
of the bonnet wall 75 is provided.
[0159] At a predetermined location in a thickness portion of the
bonnet wall 75, the screw hole 75c threaded radially outward from
the through-hole 75a is formed. The screw 75d is screwed into the
screw hole 75c from the outside, and an axial center portion of the
screwed screw 75d escapes to the side of the through-hole 75a and
is slidably fitted into the groove 731a of the diaphragm presser 73
inserted into the through-hole 75a.
[0160] The bonnet wall 75 is provided with the through-hole 75e at
a position corresponding to the screw hole 741b of the bonnet 74.
The bolt 75f is screwed into the screw hole 741b and the
through-hole 75e with the bonnet wall 75 disposed on the partition
portion 741 of the bonnet 74, so that the bonnet wall 75 is fixed
to the bonnet 74.
[0161] In the vicinity of the opening 75b in an outer peripheral
surface of the bonnet wall 75, the magnetic sensor M4 with a flat
plate shape, which is fixed so as to cover the opening 75b, is
attached. The magnetic sensor M4 can measure not only an
opening/closing state but also an opening degree of the valve V2 by
sensing a change in the distance from the magnet M3 attached to the
diaphragm presser 73. The magnetic sensor M4 attached to the bonnet
wall 75 is fixed at a predetermined position without being affected
by the vertical movement of the piston 93 or the diaphragm presser
73 caused by the opening/closing operation of the valve V2.
[0162] As illustrated in FIGS. 13 and 18, the cover portion 8
configures a fixing mechanism for pressing the actuator body 91 and
the valve body 6 to integrally hold them, and fixing a circuit
board 77 and a connector 78 provided in the circuit board 77 to the
valve V2.
[0163] The cover portion 8 includes a cover 81 and flat plates 82
and 83.
[0164] The cover 81 has a substantially U-shape, and ends of the
actuator body 91 and the valve body 6 are fitted inside.
[0165] On both side surfaces of the cover 81, screw holes 31a are
provided corresponding to positions where the actuator body 91 is
fitted. Thereby, if the screws 81b are screwed into the screw holes
31a with the valve body 6 fitted inside and the tip of the screw
81b is pressed against the valve body 6, the valve body 6 can be
held inside the cover 81.
[0166] Further, screw holes 81c are provided in a thickness portion
of the cover 81. Screws 81d are screwed into the screw holes 81c
via through-holes 82b and 83b of the plates 82 and 83, so that the
plates 82 and 83 are attached to the cover 81.
[0167] The plates 82 and 83 are screwed and fixed to the cover 81
in a state where the ends of the actuator body 91 and the valve
body 6 are fitted into the cover 81. In the fixed state, the
actuator body 91 and the valve body 6 are held between the cover 81
and the plates 82 and 83.
[0168] A notch portion 82a cut in a tongue shape is formed on the
lower side of the plate 82, and the flexible cable 76 is led to the
circuit board 77 provided with the connector 78 via the notch
portion 82a.
[0169] The plate 83 is screwed and fixed to the plate 82 and the
cover 81 with the circuit board 77 interposed between the plate 83
and the plate 82, and the circuit board 77 is held between the
plate 82 and the plate 83.
[0170] The plate 83 has a substantially rectangular through-hole
83a provided in a center portion, and the connector 78 provided in
the circuit board 77 escapes from the through-hole 83a to the
outside.
[0171] Here, when the base portion 61 is formed in a rectangular
shape in plan view, as illustrated in FIG. 13(b), the cover portion
8 fixes the connector 78 to the valve V2 in a diagonal direction of
the rectangular base portion 61. The reason why the connector 78 is
fixed in the above direction is as follows. That is, when the gas
unit 1 (2) is configured by a plurality of valves V2, due to the
demand for integration, it is preferable to align the directions of
the adjacent rectangular base portions 61 so as to eliminate gaps
maximally, and to dispose the valves V2 on a base or a manifold
block. On the other hand, when the valves are disposed and
integrated as described above, it becomes difficult to connect
terminals and the like to the connector 78. Therefore, by disposing
the connector 78 in the diagonal direction of the base portion 61,
a wider connection space can be taken as compared with when the
connector 78 is disposed toward the valve V2 disposed right beside.
As a result, the terminal or the like can be easily connected to
the connector 78, so that it is possible to prevent problems such
as disconnection due to breakage or twisting of the terminal or the
like, and to prevent problems such as the terminal or the like
hitting the valve V2 and causing an abnormality in the operation of
the valve V2.
[0172] The actuator portion 9 is disposed on the bonnet portion
7.
[0173] The actuator portion 9 includes an actuator body 91, an
actuator cap 92, a piston 93, and a spring 94, as illustrated in
FIGS. 14 and 15. Although an internal structure of the actuator
portion 9 is omitted in FIG. 16, the internal structure is as
illustrated in FIGS. 14 and 15.
[0174] The actuator body 91 is interposed between the piston 93 and
the bonnet 74.
[0175] As illustrated in FIG. 16, the actuator body 91 has a
substantially columnar shape, and in a center portion thereof, a
through-hole 91a through which the piston 93 and the diaphragm
presser 73 are inserted is provided along a longitudinal direction.
As illustrated in FIGS. 13 and 14, the piston 93 and the diaphragm
presser 73 are in contact with each other in the through-hole 91a,
and the diaphragm presser 73 moves vertically in conjunction with
the vertical movement of the piston 93.
[0176] A peripheral wall 911 made of an annular ridge is formed on
an upper end face on the side where the piston 93 is disposed, and
a drive pressure introduction chamber S1 into which a drive
pressure is introduced is formed between a flat horizontal surface
inside the peripheral wall 911 and a lower end face of a diameter
expansion portion 931 of the piston 93.
[0177] Further, a male screw is cut on an outer peripheral surface
of the actuator body 91 on the side where the piston 93 is
provided, and the male screw is screwed into a female screw cut on
an inner peripheral surface of the actuator cap 92, so that the
actuator body 91 is attached to one end of the actuator cap 92.
[0178] The center portion of the actuator body 91 in a longitudinal
direction is formed in a substantially hexagonal shape in sectional
view, and the hexagonal portion in sectional view and the upper end
of the valve body 6 are integrally pressed by the cover 81.
[0179] The actuator cap 92 is a cap-shaped member whose lower end
is open, and accommodates the piston 93 and the spring 94
inside.
[0180] An opening 92a communicating with a drive pressure
introduction path 932 of the piston 93 is provided on an upper end
face of the actuator cap 92.
[0181] The lower end of the actuator cap 92 is closed by screwing
the upper portion of the actuator body 91.
[0182] The piston 93 moves up and down according to the supply and
the stop of the drive pressure, and brings the diaphragm 72 into
and out of contact with the seat 71 via the diaphragm presser
73.
[0183] The substantially center of the piston 93 in the axial
direction is expanded in a disk shape, and the corresponding
portion configures the diameter expansion portion 931. The piston
93 receives the biasing force of the spring 94 on the top surface
side of the diameter expansion portion 931. Further, the drive
pressure introduction chamber S1 to which the drive pressure is
supplied is formed on the lower end side of the diameter expansion
portion 931.
[0184] Further, the drive pressure introduction path 932 for
causing the opening 93a formed on the upper end face and the drive
pressure introduction chamber S1 formed on the lower end side of
the diameter expansion portion 931 to communicate with each other
is provided in the piston 93. The opening 93a of the piston 93
communicates with the opening 92a of the actuator cap 92, and an
introduction pipe for introducing the drive pressure from the
outside is connected to the opening 92a. As a result, the drive
pressure is supplied to the drive pressure introduction chamber
S1.
[0185] An O-ring O91 is attached to the outer peripheral surface of
the diameter expansion portion 931 of the piston 93, and the O-ring
O91 seals a portion between the outer peripheral surface of the
diameter expansion portion 931 of the piston 93 and the peripheral
wall 911 of the actuator body 91. Further, an O-ring O92 is
attached to the lower end side of the piston 93, and the O-ring O92
seals a portion between the outer peripheral surface of the piston
93 and the inner peripheral surface of the through-hole 91a of the
actuator body 91. The O-rings O91 and O92 form the drive pressure
introduction chamber S1 communicating with the drive pressure
introduction path 932 in the piston 93, and the airtightness of the
drive pressure introduction chamber S1 is secured.
[0186] The spring 94 is wound on the outer peripheral surface of
the piston 93, and comes into contact with the top surface of the
diameter expansion portion 931 of the piston 93 to bias the piston
93 downward, that is, in a direction in which the diaphragm 72 is
pressed.
[0187] Here, the opening/closing operation of the valve according
to the supply and stop of the drive pressure will be described. If
air is supplied from an introduction pipe (not illustrated)
connected to the opening 92a, the air is introduced into the drive
pressure introduction chamber S1 via the drive pressure
introduction path 932 in the piston 93. In response to this, the
piston 93 is pushed upward against the biasing force of the spring
94. As a result, the diaphragm 72 is separated from the seat 71 to
be in an opened state, and the fluid circulates.
[0188] On the other hand, if the air is not introduced into the
drive pressure introduction chamber S1, the piston 93 is pushed
downward according to the biasing force of the spring 94. As a
result, the diaphragm 72 comes into contact with the seat 71 to be
a closed state, and the circulation of the fluid is blocked.
[0189] The valve V2 includes the pressure sensor P and the magnetic
sensor M4 as an operation information acquisition mechanism for
acquiring operation information in the device.
[0190] As illustrated in FIG. 15, the pressure sensor P is attached
to the bottom surface of the bonnet wall 75 or the flow passage
side, and communicates with the closed space S2 defined by the
diaphragm 72, the partition portion 741 of the bonnet 74, and the
diaphragm presser 73 via the communication hole 741d. The pressure
sensor P includes a pressure-sensitive element that detects a
change in the pressure, a conversion element that converts a
detection value of the pressure detected by the pressure-sensitive
element into an electric signal, and the like. Thereby, the
pressure sensor P can detect the pressure in the closed space S2
defined by the diaphragm 72, the partition portion 741 of the
bonnet 74, and the diaphragm presser 73.
[0191] A packing 26 is interposed at a location where the pressure
sensor P communicates with the communication hole 741d, and an
airtight state is secured.
[0192] The pressure sensor P may detect either the gauge pressure
or the atmospheric pressure.
[0193] The magnetic sensor M4 can measure not only an
opening/closing state but also an opening degree of the valve V2 by
sensing a change in the distance from the magnet M3 attached to the
diaphragm presser 73.
[0194] The opening/closing operation of the valve can be detected
by the magnetic sensor M4 as described below. That is, while the
magnet M3 moves vertically according to the vertical movement of
the diaphragm presser 73, the magnetic sensor M4 is fixed in the
valve body 6 together with the bonnet wall 75 and the bonnet 74. As
a result, the operation of the diaphragm presser 73 and the
opening/closing operation of the valve can be detected on the basis
of a change in the magnetic field generated between the magnet M3
moving vertically according to the vertical movement of the
diaphragm presser 73 and the magnetic sensor M4 whose position is
fixed.
[0195] Various types of magnetic sensors can be used as the
magnetic sensor M4. The magnetic sensor M4 according to an example
has a planar coil, an oscillation circuit, and an integration
circuit, and an oscillation frequency changes according to a change
in the distance from the magnet M3 located at the facing position.
In addition, by converting the frequency by the integration circuit
and obtaining an integrated value, not only the opening/closing
state of the valve V2 but also the opening degree at the time of
opening the valve can be measured.
[0196] In the present embodiment, although the magnetic sensor M4
is used, the present invention is not limited thereto. Similarly to
the above-described magnetic sensor M2, other types of sensors such
as an optical position sensor can be used as long as the position
sensor can measure a position relation between the diaphragm
presser 73 and the bonnet 74 or a distance between predetermined
locations of these members.
[0197] Even in the valve V2 according to the present embodiment, it
is desirable to select a position sensor including the magnetic
sensor M4 whose position detection accuracy falls within .+-.0.01
mm to .+-.0.001 mm. The reason is as follows. As a valve for the
semiconductor manufacturing process, fine opening degree control of
about .+-.0.01 mm is required to realize fine fluid control, but if
detection accuracy exceeding .+-.0.001 mm is used, a vibration
generated by a vacuum pump or the like in the vicinity of the valve
is detected and noise is generated.
[0198] One end of the flexible cable 76 for communication is
connected to each of the pressure sensor P and the magnetic sensor
M4, and the other end of the flexible cable 76 is connected to the
circuit board 77 provided outside the valve V2. In the present
example, a processing module for transmitting and receiving
information is configured in the circuit board 77. As a result, the
operation information acquired from the pressure sensor P or the
magnetic sensor M4 can be transmitted to an external terminal 6
connected to the connector 78.
[0199] In the valve V2, a flexible board (FPC) is used for the
flexible cable 76 and the circuit board 77, and the flexible cable
76, the circuit board 77, and the connector 78 are integrally
configured. By using the flexible board for the flexible cable 76
and the circuit board 77, it is possible to use a gap between
members as a wiring path. As a result, the valve V2 itself can be
downsized as compared with the case of using a covered wire.
[0200] Further, the processing module may be stored in the valve V2
separately from the circuit board 77, or may be configured as a
part of the pressure sensor P or the magnetic sensor M4.
[0201] Further, the type or shape of the connector 78 can be
appropriately designed according to various standards.
[0202] Further, the operation information acquisition mechanism
realized by the pressure sensor P or the magnetic sensor M4
described above can also be realized by using a drive pressure
sensor that detects the drive pressure, a temperature sensor that
measures the temperature in the flow passage, a limit switch that
detects the behavior of the piston 93 or the diaphragm presser 73,
or the like.
[0203] In the valve V2 described above, the piston 93 and the
diaphragm presser 73 are configured separately. However, the magnet
M3 is attached to the diaphragm presser 73. Thereby, it is possible
to determine an operation failure of the diaphragm presser 73. That
is, normally, the diaphragm presser 73 follows the piston 93 and
rises by the valve opening operation. However, when the valve is
closed, the valve chamber 712 is depressurized to near the vacuum,
so that the diaphragm 72 is attracted to the seat 71. As a result,
even though the piston 93 rises, the diaphragm presser 73 may not
follow the piston 93 and may remain in contact with the diaphragm
72. As a result, the diaphragm 72 may keep the flow passage
blocked. However, even in this case, in the valve V2, the magnet M3
is interlocked with the diaphragm presser 73, so that the operation
of the diaphragm presser 73 can be determined from the value
detected by the magnetic sensor M4, and the operation failure can
be determined.
[0204] The determination of the operation failure of the diaphragm
presser 73 is enabled because the magnetic sensor M4 is attached to
the diaphragm presser 73 which does not move vertically like the
piston 93 and the diaphragm presser 73 according to the opening and
closing operation of the valve V2, so that a relative operation of
the diaphragm presser 73 can be identified. Therefore, a member to
which the magnetic sensor M4 is to be attached may be fixed at a
predetermined position regardless of the opening/closing operation
of the valve V2 in that the operation of the diaphragm presser 73
can identified and the operation failure can be determined.
[0205] As a specific abnormality determination method, the
abnormality determination unit determines whether or not a change
in the distance between the magnet M3 and the magnetic sensor M4
corresponding to the valve opening operation is matched with a
change in the distance at the time of normality, from the detection
value of the magnetic sensor M4. If they are matched, it is
determined that there is no abnormality, and if they are not
matched, it is determined that there is an abnormality. In
particular, when there is no change in the distance, it is
understood that the diaphragm presser 73 keeps pressing the
diaphragm 72.
[0206] As described above, in the valve V2, even if the piston 93
and the diaphragm presser 73 are configured separately, it is
possible to determine the operation failure of the diaphragm
presser 73.
REFERENCE SIGNS LIST
[0207] 1, 2 Gas unit [0208] 10, 10a, 10b, 10c Main cable [0209]
101, 102 Branch cable [0210] 11, 12, 13 Extension cable [0211] 111,
112, 113, 114 Sub-cable [0212] 121, 122, 123, 124 Sub-cable [0213]
131, 132, 133, 134 Sub-cable [0214] 20, 20a, 20b, 20c Main tube
[0215] 21, 22, 23 Extension tube [0216] 211, 212, 213 Extension
tube [0217] 214, 215, 216, 217, 218 Sub-tube [0218] 221, 222, 223
Extension tube [0219] 224, 225, 226, 227, 228 Sub-tube [0220] 231,
232, 233 Extension tube [0221] 234, 235, 236, 327, 238 Sub-tube
[0222] 3 Valve body [0223] 3a Drive pressure introduction port
[0224] 4 Drive pressure control device [0225] 40 Casing [0226] 411,
412 Automatic valve [0227] 421, 422 Valve drive unit [0228] 431,
432, 433 Drive pressure introduction path [0229] 44 Exhaust passage
[0230] 45 Wiring [0231] 51 Diaphragm [0232] 52 Pressing adapter
[0233] 53 Stem [0234] 6 Valve body [0235] 61 Base portion [0236] 62
Cylindrical portion [0237] 7 Bonnet portion [0238] 71 Seat [0239]
72 Diaphragm [0240] 73 Diaphragm presser [0241] 74 Bonnet [0242] 75
Bonnet wall [0243] 76 Flexible cable [0244] 77 Circuit board [0245]
78 Connector [0246] 8 Cover portion [0247] 81 Cover [0248] 82 Plate
[0249] 83 Plate [0250] 9 Actuator portion [0251] 91 Actuator body
[0252] 92 Actuator cap [0253] 93 Piston [0254] 94 Spring [0255] L1,
L2, L3 Fluid supply line [0256] C1, C2, C3 Branch connector [0257]
F (F1, F2, F3) Flow rate control device [0258] J1 Branch joint
[0259] J11, J111, J112, J113 Joint [0260] J12, J121, J122, J123
Joint [0261] J13, J131, J132, J133 Joint [0262] M1, M3 Magnet
[0263] M2, M4 Magnetic sensor [0264] V1 (V11 to V14, V21 to 24, V31
to 34), V2 Valve [0265] P Pressure sensor [0266] S1 Drive pressure
introduction chamber [0267] S2 Closed space
* * * * *