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Patent Abstract
A diaphragm-type solenoid valve has a valve body 3 fixed onto a
base, a diaphragm 4 for opening and closing a valve seat 13 provided
to an inner end of a second port 12, a plate 5 for forming a driving
chamber 14 between the plate 5 and the diaphragm sandwiched between
the plate 5 and the valve body 3, and a pilot valve 6 for supplying
pilot fluid pressure to the driving chamber 14. In the diaphragm,
a disc 20 is encapsulated in a portion facing the port 12, a sealing
rib 21 corresponding to the valve seat is provided, and cushion
projecting portions 22 and 23 for coming in contact with cushion
receiving portions 32 and 33 of the plate 5 in valve opening are
formed behind the portion where the disc is encapsulated.
Patent Claims
What is claimed is:
1. A diaphragm-type solenoid valve comprising a valve body having
a first port and a second port for main fluid in a mounting face
to be mounted to a base, a valve seat mounted in a flow path connecting
both said ports, a diaphragm for opening and closing said valve
seat, a plate for sandwiching and fixing an outer peripheral portion
of said diaphragm between said plate and said valve body, a driving
chamber formed between said plate and said diaphragm to be separated
from said flow path, and a pilot valve disposed on said plate to
supply pilot fluid different from said main fluid to said driving
chamber, wherein said diaphragm has a central main body portion
for opening and closing said valve seat and an elastic support portion
surrounding said main body portion, a disc is encapsulated in said
main body portion, a sealing rib for coming in contact with and
separating from said valve seat is provided to one face of said
main body portion, and a cushion projecting portion for coming in
contact with a cushion receiving portion of said plate in valve
opening is formed on a back face of said main body portion.
2. A diaphragm-type solenoid valve according to claim 1, wherein
diaphragm receiving faces in shapes patterned on a shape of said
elastic support portion are formed on opposed faces of said valve
body and said plate facing said elastic support portion of said
diaphragm and said elastic support portion comes in contact with
said diaphragm receiving faces in opening and closing of said diaphragm
to thereby prevent excessive deformation of said diaphragm.
3. A diaphragm-type solenoid valve according to claim 1, wherein
said first port is in an annular shape and said second port opens
at a center of said first port.
4. A diaphragm-type solenoid valve according to claim 1, wherein
a pilot air supply hole and a pilot exhaust hole communicating with
said pilot valve are provided to said mounting face of said valve
body.
5. A diaphragm-type solenoid valve complex body formed by mounting
one diaphragm-type solenoid valve according to claim 1 onto a base
having a supply port and an output port for main fluid and connecting
each of said first and second ports to one of said supply port and
said output port so as to have a function of a two-port valve by
said solenoid valve and said base.
6. A diaphragm-type solenoid valve complex body formed by mounting
a plurality of diaphragm-type solenoid valves according to claim
1 onto a base having a supply port, at least one output port, and
a discharge port for main fluid and connecting said supply port,
said output port, and said discharge port to first and second ports
of said respective solenoid valves by a connecting path in said
base so as to have a function of a three-port valve by said plurality
of solenoid valves and said base.
7. A diaphragm-type solenoid valve complex body according to claim
6, wherein said base has first and second two output ports, first
to fourth four diaphragm-type solenoid valves are mounted onto said
base, said first ports of said first and second solenoid valves
are respectively connected to said supply port, said second ports
of said third and fourth solenoid valves are respectively connected
to said discharge port, said second port of said first solenoid
valve and said first port of said third solenoid valve are connected
to said first output port, and said second port of said second solenoid
valve and said first port of said fourth solenoid valve are connected
to said second output port.
Patent Description
TECHNICAL FIELD
[0001] The present invention relates to a diaphragm-type solenoid
valve which is for use with various flow path structures by mounting
the required number of solenoid valves onto a base and which is
suitable for supplying and discharging special medical fluid which
must not include foreign matter.
PRIOR ART
[0002] A diaphragm-type solenoid valve is conventionally known
as a valve which can easily suppress inclusion of foreign matter
or the like by independently forming a flow path for main fluid.
However, because the diaphragm-type solenoid valve is generally
formed as a single solenoid valve, it is difficult to easily connect
the solenoid valve so as to obtain various flow path structures.
[0003] If the diaphragm-type valve is used for a flow path for
fluid which must not include foreign matter or which is toxic, it
is necessary to give sufficient consideration such that the diaphragm
is not damaged due to fatigue or the like.
DISCLOSURE OF THE INVENTION
[0004] The present invention has been accomplished to solve the
above problems and it is basically a technical object of the invention
to provide a diaphragm-type solenoid valve by which various flow
path structures can be obtained by making it possible to mount valve
bodies of the required number of diaphragm-type solenoid valves
to a base having a proper flow path.
[0005] It is another technical object of the invention to provide
a diaphragm-type solenoid valve in which a sliding portion and excessive
deformation are generated nowhere in operation of a diaphragm and
the diaphragm can be prevented from being damaged due to fatigue
or the like.
[0006] To achieve the above objects, according to the invention,
there is provided a diaphragm-type solenoid valve comprising a valve
body having a first port and a second port in a mounting face to
be mounted to a base, a valve seat mounted in a flow path connecting
both the ports, a diaphragm for opening and closing the valve seat,
a plate for sandwiching and fixing an outer peripheral portion of
the diaphragm between the plate and the valve body, a driving chamber
formed between the plate and the diaphragm to be separated from
the flow path, and a pilot valve disposed on the plate to supply
pilot fluid different from the main fluid to the driving chamber.
[0007] The diaphragm has a central main body portion for opening
and closing the valve seat and an elastic support portion surrounding
the main body portion, a disc is encapsulated in the main body portion,
a sealing rib for coming in contact with and separating from the
valve seat is provided to one face of the main body portion, and
a cushion projecting portion for coming in contact with a cushion
receiving portion of the plate in valve opening is formed on a back
face of the main body portion.
[0008] In the diaphragm-type solenoid valve, diaphragm receiving
faces in shapes patterned on a shape of the elastic support portion
are formed on opposed faces of the valve body and the plate facing
the elastic support portion of the diaphragm and the elastic support
portion comes in contact with the diaphragm receiving faces in opening
and closing of the diaphragm to thereby prevent excessive deformation
of the diaphragm.
[0009] In the invention, it is preferable that the first port is
in an annular shape and the second port opens at a center of the
first port.
[0010] It is preferable that a pilot air supply hole and a pilot
exhaust hole communicating with the pilot valve are provided to
the mounting face of the valve body.
[0011] According to the invention, there is provided a diaphragm-type
solenoid valve complex body formed by mounting one diaphragm-type
solenoid valve onto a base having a supply port and an output port
for main fluid and connecting each of the first and second ports
to one of the supply port and the output port so as to have a function
of a two-port valve by the solenoid valve and the base.
[0012] There is provided a diaphragm-type solenoid valve complex
body formed by mounting a plurality of diaphragm-type solenoid valves
onto a base having a supply port, at least one output port, and
a discharge port for main fluid and connecting the supply port,
the output port, and the discharge port to first and second ports
of the respective solenoid valves by a connecting path in the base
so as to have a function of a three-port valve by the plurality
of solenoid valves and the base.
[0013] According to a concrete embodiment of the three-port valve,
the base has first and second two output ports, first to fourth
four diaphragm-type solenoid valves are mounted onto the base, the
first ports of the first and second solenoid valves are respectively
connected to the supply port, the second ports of the third and
fourth solenoid valves are respectively connected to the discharge
port, the second port of the first solenoid valve and the first
port of the third solenoid valve are connected to the first output
port, and the second port of the second solenoid valve and the first
port of the fourth solenoid valve are connected to the second output
port.
[0014] In the diaphragm-type solenoid valve of the invention, because
the disc is encapsulated in the main body portion of the diaphragm
and the cushion projecting portion for coming in contact with the
cushion receiving portion provided to the plate in valve opening
is formed behind the main body portion, impact force acting on the
diaphragm in valve opening can be absorbed to protect the diaphragm.
Furthermore, because the diaphragm receiving faces for preventing
excessive deformation of the diaphragm when the diaphragm is pressed
by operating force of the fluid are formed at faces of the valve
body and the plate opposed to the main body portion, excessive deformation
is generated nowhere in operation of the diaphragm and the diaphragm
can be prevented to the utmost from being damaged due to fatigue
or the like.
[0015] By mounting the diaphragm-type solenoid valve on a base
having a flow path connected to the first and second ports to open
and close the flow path, it is possible to form a complex valve
having a function of a two-port valve or a three-port valve by the
diaphragm-type solenoid valve and the base to obtain various flow
path structures according to the flow path provided in the base.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] FIG. 1 is a sectional view of a first embodiment of a diaphragm-type
solenoid valve according to the present invention.
[0017] FIG. 2 is a bottom view of the diaphragm-type solenoid valve.
[0018] FIG. 3 is a sectional view of a second embodiment of the
diaphragm-type solenoid valve according to the invention.
[0019] FIG. 4 is a perspective view of an example of a state in
which the diaphragm-type solenoid valves of the invention are mounted
to a base.
[0020] FIG. 5 is a fluid circuit diagram showing a connecting state
of the diaphragm-type solenoid valves by the base in FIG. 4 by using
symbols.
[0021] FIG. 6 is a perspective view of another example of the state
in which the diaphragm-type solenoid valves of the invention are
mounted to the base.
[0022] FIG. 7 is a fluid circuit diagram showing a connecting state
of the diaphragm-type solenoid valves by the base in FIG. 6 by using
symbols.
DETAILED DESCRIPTION
[0023] FIG. 1 shows a first embodiment of a diaphragm-type solenoid
valve according to the present invention.
[0024] The diaphragm-type solenoid valve 1 of the first embodiment
is used in a state in which the valve is mounted onto a base 2,
and more specifically, a base 2A or 2B which will be described later
by means of FIGS. 4 and 6. The solenoid valve 1 includes a valve
body 3 having in a mounting face 3a to be fixed to the base a first
port 11 and a second port 12 communicating with two flow paths 2a
and 2b opening on the base, a valve seat 13 formed at a mouth edge
portion of the second port 12 in a flow path connecting both the
ports 11 and 12, a diaphragm 4 for opening and closing the valve
seat 13, a plate 5 for sandwiching and fixing an outer peripheral
portion of the diaphragm 4 between the plate 5 and the valve body
3, a driving chamber 14 formed between the plate 5 and the diaphragm
4 to be separated from the flow path, and a pilot valve 6 disposed
on the plate 5 to supply pilot fluid which is different from main
fluid to the driving chamber 14. A diaphragm valve main body formed
of the valve body 3, the diaphragm 4, and the plate 5 is assembled
by seating the diaphragm 4 on the valve body 3, placing the plate
5 on the diaphragm 4, and fastening the plate 5 to the valve body
3.
[0025] As shown in FIG. 2, the first port 11 is in an annular shape,
the second port 12 is provided to a central portion of the first
port 11, a peripheral wall of the first port 11 and a peripheral
wall of the second port 12 are connected to each other by a plurality
of bridges 15 positioned in radial directions, and the valve seat
13 is provided to a periphery of an inner end of the second port
12. However, the valve seat 13 may be provided to the first port
11 side or to inner ends of both the ports 11 and 12. In the mounting
face 3a of the valve body 3, a pilot air supply hole 16 and a pilot
exhaust hole 17 open outside the first port 11.
[0026] The diaphragm 4 is made of material having rubber elasticity
and has a central main body portion 4a for opening and closing the
valve seat 13 and an annular elastic support portion 4b surrounding
the main body portion 4a. In the main body portion 4a, a hard disc
20 is encapsulated. The disc 20 is formed to be slightly larger
than a diameter of the valve seat 13. A sealing rib 21 is formed
on one face of the main body portion 4a to face the valve seat 13
at a peripheral portion of the disc 20 and a cushion projecting
portion 22 in a central position and the large number of small cushion
projecting portions 23 at a peripheral portion are formed respectively
on a back face of the main body portion 4a. The cushion projecting
portions 22 and 23 come in contact with cushion receiving portions
32 and 33 provided to the plate 5 in valve opening when the diaphragm
4 separates from the valve body 3 and absorb impact force acting
on the diaphragm 4 in valve opening.
[0027] An inner bottom of an annular groove formed around the protruding
cushion receiving portion 32 at the plate 5 is formed as a spring
seat 34 and a return spring 35 is disposed between the spring seat
34 and a periphery of the cushion projecting portion 23 of the diaphragm
4.
[0028] Furthermore, connecting holes 24 and 25 are respectively
formed in positions of a periphery of the diaphragm 4 corresponding
to the pilot air supply hole 16 and the pilot exhaust hole 17 of
the valve body 3.
[0029] The plate 5 for airtightlv sandwiching the diaphragm 4 between
the Plate 5 and the valve body 3 has a flow path for supplying pilot
fluid pressure to the driving chamber 14 by the pilot valve 6 disposed
on the plate 5. The flow path is formed of an air supply flow path
36 for connecting the pilot air supply hole 16 provided to the valve
body 3 to a supply port 41 of the pilot valve 6, an output flow
path 37 for connecting an output port 42 of the pilot valve 6 to
the driving chamber 14, and an exhaust flow path 38 for connecting
an exhaust port 43 of the pilot valve 6 to the pilot exhaust hole
17 of the valve body 3.
[0030] The pilot valve 6 has a movable core 47 attracted to a fixed
core 46 by energizing a solenoid 45. An exhaust-side valve body
48 provided to the movable core 47 faces a pilot exhaust valve seat
provided to the exhaust port 43 and an air supply-side valve body
49 connected to the exhaust-side valve body 48 through a pressing
lever (not shown) faces a pilot air supply valve seat provided to
the supply port 41. A reference numeral 51 in FIG. 1 designates
a manual operation member for use when the movable core 47 does
not operate, 52 designates a feeding socket, 53 designates a receiving
terminal, and 54 designates a substrate on which electronic parts
are placed.
[0031] Opposed faces of the valve body 3 and the plate 5 facing
the elastic support portion 4b of the diaphragm 4 are formed with
diaphragm receiving faces 19 and 39 in shapes patterned on a shape
of the elastic support portion 4b. When the diaphragm 4 is pushed
by operating force of fluid in opening and closing of the diaphragm
4, the elastic support portion 4b comes in contact with the diaphragm
receiving faces 19 and 39 to thereby prevent excessive deformation
of the diaphragm 4. The diaphragm 4 in FIG. 1 is shown in a state
in which the diaphragm 4 is pressed against the diaphragm receiving
face 19 of the valve body 3 by fluid pressure in the driving chamber
14 and the diaphragm shown with a chain line in FIG. 3 is shown
in a state in which the diaphragm is pressed against the diaphragm
receiving face 39 of the plate 5 by fluid pressure on the sides
of the first and second ports 11 and 12.
[0032] In the diaphragm-type solenoid valve 1 having the above
structure, when the solenoid 45 of the pilot valve 6 is not energized,
the valve seat provided to the exhaust port 43 is closed with the
exhaust-side valve body 48 as the movable core 47 is returned by
the spring and at the same time, the valve seat provided to the
supply port 41 is opened by the air supply-side valve body 49, and
pilot fluid pressure from the pilot air supply hole 16 is supplied
from the air supply flow path 36 and the supply port 41 through
the output port 42 and the output flow path 37 to the driving chamber
14 as shown in FIG. 1. As a result, the diaphragm 4 is pressed toward
the valve body 3 by pilot fluid pressure in the driving chamber
14 and biasing force of the return spring 35 to close the valve
seat 13 and to close the flow path between the first and second
ports.
[0033] The pilot fluid pressure supplied to and discharged from
the driving chamber 14 may be about the same as pressure of main
fluid flowing between the first and second ports 11 and 12 or may
be higher than the pressure of the main fluid if necessary.
[0034] On the other hand, when the solenoid 45 is energized, the
valve seat provided to the exhaust port 43 is opened by the exhaust-side
valve body 48 and at the same time, the valve seat provided to the
supply port 41 is closed with the air supply-side valve body 49,
the pilot fluid pressure in the driving chamber 14 is introduced
from the output flow path 37 and the output port 42 through a periphery
of the pressing lever into a valve chamber where the exhaust-side
valve body 48 exists and discharged outside from the valve seat
provided to the exhaust port 43 through the exhaust flow path 38
and the pilot exhaust hole 17. As a result, the fluid pressure of
the main fluid of the first or second port 11 or 12 presses the
diaphragm 4 toward the driving chamber 14 against the biasing force
of the return spring 35 to open the valve seat 13 and to open the
flow path between the first and second ports.
[0035] Because the driving chamber 14 and the flow path for the
main fluid between the first and second ports 11 and 12 are separated
by the diaphragm 4, the diaphragm-type solenoid valve can be applied
to medical main fluid or other various main fluid. Because the disc
20 is encapsulated in the main body portion 4a for opening and closing
the valve seat 13 at a center of the diaphragm 4 and the cushion
projecting portions 22 and 23 for coming in contact with the cushion
receiving portions 32 and 33 provided to the plate 5 in valve opening
are formed on the back face of the main body portion 4a, impact
force acting on the diaphragm 4 in valve opening can be absorbed
to protect the diaphragm 4.
[0036] Furthermore, because the diaphragm receiving faces 19 and
39 are formed at the valve body 3 and the plate 5 such that the
elastic support portion 4b comes in contact with and is supported
by the diaphragm receiving faces 19 and 39 in opening and closing
of the diaphragm 4, excessive deformation is generated nowhere in
operation of the diaphragm 4 and the diaphragm 4 can be prevented
to the utmost from being damaged due to fatigue.
[0037] FIG. 3 shows a second embodiment of the diaphragm-type solenoid
valve according to the invention. The second embodiment is different
from the first embodiment in that the diaphragm 4 is not provided
with the return spring 35.
[0038] In the second embodiment, unlike the first embodiment, the
diaphragm 4 is pressed toward the valve body 3 by only operating
force of the pilot fluid in the driving chamber 14. Therefore, in
order to close the valve seat 13 to reliably close the flow path
between the first and second ports, it is preferable that pressure
of pilot fluid supplied to the driving chamber 14 is higher than
pressure of main fluid flowing between the first and second ports
11 and 12.
[0039] Because there is no difference in other structures and operation
between the second embodiment and the first embodiment, main portions
in the drawing are provided with the same reference numerals as
those in the first embodiment to omit description of them.
[0040] FIG. 4 shows a state in which a plurality of diaphragm-type
solenoid valves 1A to 1D are mounted onto a base 2A having a supply
port P, output ports A and B, and a discharge port E to form a diaphragm-type
solenoid valve complex body having a function of a three-port valve
from the solenoid valves 1A to 1D and the base 2A and FIG. 5 shows
a state in which the respective ports and the solenoid valves 1A
to 1D are connected through connecting paths in the base 2A by using
symbols.
[0041] In other words, in positions corresponding to the respective
solenoid valves 1A to 1D on a solenoid valve mounting face of the
base 2A, openings communicating with the respective ports P, A,
B, and E are provided while being connected to have special relationships
through the connecting paths in the base 2A, though the openings
are not especially shown in the drawings. If the solenoid valves
1A to 1D are mounted to the mounting face, the first and second
ports 11 and 12 of the respective solenoid valves are connected
to the respective openings.
[0042] Specifically, as shown in FIG. 5, the first ports 11 of
the first and second solenoid valves 1A and 1B are respectively
connected to the supply port P, the second ports 12 of the third
and fourth solenoid valves 1C and 1D are respectively connected
to the discharge port E, the second port 12 of the first solenoid
valve 1A and the first port 11 of the third solenoid valve 1C are
connected to the first output port A, and the second port 12 of
the second solenoid valve 1B and the first port 11 of the fourth
solenoid valve 1D are connected to the second output port B. Therefore,
the first and second solenoid valves 1A and 1B respectively have
functions of supplying or not supplying fluid from the supply port
P to the output ports A and B and the third and fourth solenoid
valves 1C and 1D respectively have functions of discharging or not
discharging fluid of the output ports A and B.
[0043] The base 2A is formed with a supply port and a discharge
port for pilot fluid, openings communicating with the respective
ports are formed on the solenoid valve mounting face, and the openings
are connected to the pilot air supply holes 16 and the pilot exhaust
holes 17 of the respective solenoid valves.
[0044] FIG. 6 shows a state in which a plurality of diaphragm-type
solenoid valves 1A to 1D are mounted onto another base 2B and FIG.
7 shows a state in which the respective ports provided to the base
2B and the solenoid valves 1A to 1D are connected through connecting
paths in the base 2B by using symbols.
[0045] A structure shown in FIG. 6 is different only in that the
base 2B has solenoid mounting faces on its two opposed faces and
has two solenoid valves on each face and that the supply port P
and the discharge port E separately open in the two opposed faces
of the base and the structure in FIG. 6 is substantially the same
as that in FIG. 4 in relationships of connection between the respective
ports P, A, B, and E on the base 2B and the first and second ports
11 and 12 in the respective solenoid valves 1A to 1D.
[0046] Besides the examples in FIGS. 4 and 6, it is also possible
to mount two diaphragm-type solenoid valves on a base having a supply
port P, one output port A, and a discharge port E to form a diaphragm-type
solenoid valve complex body having a function of a three-port valve
or it is possible to mount one diaphragm-type solenoid valve on
a base having two ports to form a diaphragm-type solenoid valve
complex body having a function of a two-port valve.
[0047] As described above, according to the diaphragm-type solenoid
valve having the above structure, it is possible to mount a single
diaphragm-type solenoid valve or a combination of a plurality of
diaphragm-type solenoid valves on a base having a proper flow path
to form a diaphragm-type solenoid valve complex body having a function
of a two-port valve, a three-port valve or other arbitrary functions
according to the flow path formed in the base. According to the
flow path provided in the base, it is possible to apply various
flow path structures.
[0048] According to the diaphragm-type solenoid valve of the invention
which has been described above in detail, it is possible to obtain
various flow path structures by mounting the valve bodies of the
required number of diaphragm-type solenoid valves to the base having
the proper flow path and to obtain a diaphragm-type solenoid valve
in which a sliding portion and excessive deformation are generated
nowhere in operation of the diaphragm and the diaphragm can be prevented
from being damaged due to fatigue or the like. |