U.S. patent application number 15/755134 was filed with the patent office on 2018-08-16 for electromagnetic-type pump.
The applicant listed for this patent is FUJI CLEAN CO., LTD.. Invention is credited to Norihiro MINOGUCHI, Yuji YAMADA.
Application Number | 20180230989 15/755134 |
Document ID | / |
Family ID | 58187140 |
Filed Date | 2018-08-16 |
United States Patent
Application |
20180230989 |
Kind Code |
A1 |
MINOGUCHI; Norihiro ; et
al. |
August 16, 2018 |
ELECTROMAGNETIC-TYPE PUMP
Abstract
An electromagnetically driven diaphragm pump (100) includes a
diaphragm (142), a first center disk (150) and a second center disk
(160), and an oscillator (130). The first center disk (150) has a
circular-ring shaped first disk contact surface (151a) that is
disposed opposing an outer surface (144) of the diaphragm (142) and
that makes contact with the outer surface (144) when the oscillator
(130) is in the neutral position. The second center disk (160) has
a circular-ring shaped second disk contact surface (161a) that is
disposed opposing an inner surface (145) of the diaphragm (142),
and makes contact with the inner surface (145) when the oscillator
(130) is in the neutral position. The second center disk (160) has
an outer diameter (D2b) set in the range of 1.05-1.30 times an
outer diameter (D1b) of the first disk contact surface (151a).
Inventors: |
MINOGUCHI; Norihiro; (Aichi,
JP) ; YAMADA; Yuji; (Aichi, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
FUJI CLEAN CO., LTD. |
Nagoya-shi |
|
JP |
|
|
Family ID: |
58187140 |
Appl. No.: |
15/755134 |
Filed: |
April 4, 2016 |
PCT Filed: |
April 4, 2016 |
PCT NO: |
PCT/JP2016/061038 |
371 Date: |
March 5, 2018 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F04B 45/04 20130101;
F04B 43/02 20130101; F04B 43/0054 20130101; F04B 53/10 20130101;
F04B 45/047 20130101; F04B 43/04 20130101 |
International
Class: |
F04B 45/047 20060101
F04B045/047; F04B 53/10 20060101 F04B053/10 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 28, 2015 |
JP |
2015-168540 |
Claims
1. A pump comprising: a discoidal diaphragm composed of an elastic
material; a first center disk and a second center disk that are
both discoidal and concentric with the diaphragm, the first center
disk being fixed with respect to the second center disk such that a
central area of the diaphragm is interposed between the first
center disk and the second center disk; an oscillator coupled to at
least one of the first center disk and the second center disk and
configured to reciprocally oscillates the diaphragm in an intake
direction and a discharge direction about a neutral position; and a
valve case disposed on a side of the oscillator that is opposite of
the diaphragm, the valve case having a compression chamber for
sucking in a fluid during movement in the intake direction of the
oscillator and for compressing that fluid during movement in the
discharge direction of the oscillator; wherein: the first center
disk has a circular-ring shaped first disk contact surface that is
disposed opposing an outer surface of the diaphragm that (i) faces
towards the compression chamber of the valve case, (ii) makes
contact with the outer surface when the oscillator is in the
neutral position and (iii) has an outer diameter; the second center
disk has a circular-ring shaped second disk contact surface that
(i) is disposed opposing an inner surface of the diaphragm that
faces towards the oscillator, (ii) makes contact with the inner
surface when the oscillator is in the neutral position, and (iii)
has an outer diameter set in the range of 1.05-1.30 times the outer
diameter of the first disk contact surface; and the diaphragm, the
first center disk and the second center disk are configured such
that, during reciprocating oscillation in the intake direction and
the discharge direction of the oscillator, the diaphragm centrally
bends at a contact part within the outer surface of the diaphragm,
with respect to an outer circumference of the first disk contact
surface of the first center disk, and centrally bends at a contact
part within the inner surface of the diaphragm, with respect to an
outer circumference of the second disk contact surface of the
second center disk.
2. The pump according to claim 1, wherein: the first center disk
has a first disk curved surface that extends from the outer
circumference of the first disk contact surface while curving
outward in a radial direction of the first center disk with a
radius of curvature, the first disk curved surface having a ring
shape in a circumferential direction of the first center disk; and
the second center disk has a second disk curved surface that
extends from the outer circumference of the second disk contact
surface while curving outward in a radial direction of the second
center disk with the same radius of curvature as that of the first
disk curved surface, the second disk curved surface having a ring
shape in a circumferential direction of the second center disk.
3. A pump comprising: an elastic diaphragm; a first center disk, a
second center disk fixed with respect to the first center disk such
that a central area of the diaphragm is interposed between the
first center disk and the second center disk; an electromagnetic
oscillator coupled to at least one of the first center disk and the
second center disk and configured to reciprocally oscillate the
diaphragm about a neutral position; and a valve case disposed such
that the diaphragm is interposed between the electromagnetic
oscillator and the valve case, the valve case having a compression
chamber configured to intake a fluid when the electromagnetic
oscillator moves in an intake direction and to compress the fluid
when the electromagnetic oscillator moves in a discharge direction;
wherein: the first center disk has a first circumference with a
first diameter and the second center disk has a second
circumference with a second diameter, the first circumference is a
radially outermost portion of the first center disk that makes
contact with the diaphragm when the diaphragm is located in the
neutral position, the second circumference is a radially outermost
portion of the second center disk that makes contact with the
diaphragm when the diaphragm is located in the neutral position,
the second diameter is between 1.05 and 1.30 times greater than the
first diameter.
4. The pump according to claim 3, wherein the diaphragm, the first
center disk and the second center disk are configured such that:
the diaphragm bends along a first circle adjacent the first
circumference of the first center disk when the diaphragm moves in
the intake direction, the diaphragm bends along a second circle
adjacent the second circumference of the second center disk when
the diaphragm moves in the discharge direction, the second circle
being larger than the first circle.
5. The pump according to claim 4, wherein the first center disk is
disposed between the diaphragm and the valve case and the second
center disk is disposed between the diaphragm and the
electromagnetic oscillator.
6. The pump according to claim 5, wherein: the first center disk
has a third circumference with a third diameter and the second
center disk has a fourth circumference with a fourth diameter, the
third circumference is a radially outermost edge of the first
center disk, the fourth circumference is a radially outermost edge
of the second center disk, the first center disk curves away from
the diaphragm between the first circumference and the third
circumference, and the second center disk curves away from the
diaphragm between the second circumference and the fourth
circumference.
7. The pump according to claim 6, wherein: the first center disk
curves away from the diaphragm between the first circumference and
the third circumference with a first radius of curvature, and the
second center disk curves away from the diaphragm between the
second circumference and the fourth circumference with a second
radius of curvature.
8. The pump according to claim 7, wherein the elastic diaphragm is
composed of a rubber material.
9. The pump according to claim 8, wherein the second circle has a
diameter that is between 1.05 and 1.30 times greater than the
diameter of the first circle.
10. The pump according to claim 4, wherein the second circle has a
diameter that is between 1.05 and 1.30 times greater than the
diameter of the first circle.
11. The pump according to claim 3, wherein the first center disk is
disposed between the diaphragm and the valve case and the second
center disk is disposed between the diaphragm and the
electromagnetic oscillator.
12. The pump according to claim 3, wherein: the first center disk
has a third circumference with a third diameter and the second
center disk has a fourth circumference with a fourth diameter, the
third circumference is a radially outermost edge of the first
center disk, the fourth circumference is a radially outermost edge
of the second center disk, the first center disk curves away from
the diaphragm between the first circumference and the third
circumference, and the second center disk curves away from the
diaphragm between the second circumference and the fourth
circumference.
13. The pump according to claim 12, wherein: the first center disk
curves away from the diaphragm between the first circumference and
the third circumference with a first radius of curvature, and the
second center disk curves away from the diaphragm between the
second circumference and the fourth circumference with a second
radius of curvature.
14. The pump according to claim 13, wherein the first radius of
curvature is equal to the second radius of curvature.
Description
TECHNICAL FIELD
[0001] The present invention relates to an electromagnetic-type
pump.
BACKGROUND ART
[0002] An electromagnetic-type pump is a pump configured to suck in
and discharge a fluid in accordance with linearly reciprocating
oscillation of an oscillator caused by an electromagnetic coil. Up
to now, a well-known example of this type of electromagnetic-type
pump is one that is structured such that a central area of a
diaphragm having elastic properties is sandwiched, from both
surfaces, by two center disks, and the oscillator is coupled to
these two center disks. For example, this type of
electromagnetic-type pump is disclosed in Patent Document 1
mentioned below.
PRIOR ART LITERATURE
Patent Documents
[0003] Patent Document 1
[0004] Japanese Laid-open Patent Publication 2000-170660
[0005] Patent Document 2
[0006] Japanese Laid-open Utility Model Publication H6-53858
SUMMARY OF THE INVENTION
[0007] The electromagnetic-type pump disclosed in the
above-mentioned Patent Document 1 comprises, as the two center
disks, a first center disk, which is located on an outer side of
the pump, and a second center disk, which is located on an inner
side of the pump. The electromagnetic-type pump is configured such
that a diameter (clamping diameter) of an area in which the first
center disk makes contact with the diaphragm when the oscillator is
in a neutral position and a diameter (clamping diameter) of an area
in which the second center disk makes contact with the diaphragm
when the oscillator is in the neutral position are identical.
[0008] Consequently, during reciprocating oscillation in an intake
direction and a discharge direction of the oscillator, both an
outer surface and an inner surface of the diaphragm bend at the
same location in the radial direction. In the case of an
electromagnetic-type pump having the present configuration, there
is a concern that the service life of the diaphragm will decrease
because a local load concentration arises in the diaphragm owing to
the reciprocating movement of the oscillator.
[0009] Accordingly, to prevent a decrease in the service life of
the diaphragm, it is conceivable to refer to the apparatus
disclosed in the above-mentioned Patent Document 2. This apparatus
is configured such that the position in the radial direction of the
bent part on the outer surface of the diaphragm (hereinbelow, also
called a "first radial-direction position") and the position in the
radial direction of the bent part on the inner surface of the
diaphragm (hereinbelow, also called a "second radial-direction
position") differ from one another. Moreover, in addition to
preventing a decrease in the service life of the diaphragm, there
is also a demand to design the electromagnetic-type pump more
compactly. To meet such a demand, it is insufficient to merely make
the first radial-direction position and the second radial-direction
position of the diaphragm different.
Problems to be Solved by the Invention
[0010] Accordingly, the present invention was conceived considering
the above-mentioned points, and one object of the present invention
is to provide an effective technique that, in an
electromagnetic-type pump comprising a diaphragm coupled to an
electromagnetically driven oscillator, prolongs the service life of
the diaphragm and achieves compactness of the pump.
Means for Solving the Problems
[0011] To achieve the above-mentioned object, an
electromagnetic-type pump (100) according to the present invention
comprises a diaphragm (142), a first center disk (150) and a center
disk (160), an oscillator (130), and a valve case (103). The
diaphragm (142) is a discoidal member that is composed of an
elastic material. The first center disk (150) and the second center
disk (160) are both discoidal and concentric with the diaphragm
(142) and are fixed to one another in the state in which they
sandwich--from both surfaces in a sheet-thickness direction--a
central area of the diaphragm (142). The oscillator (130) is
coupled to at least one of the first center disk (150) and the
second center disk (160) and reciprocatively oscillates in an
intake direction and a discharge direction about a neutral
position. The valve case (103), on an opposite side of the
oscillator (130), sandwiching the diaphragm (142), has a
compression chamber (104) for sucking in a fluid during movement in
the intake direction of the oscillator (130) and for compressing
that fluid during movement in the discharge direction of the
oscillator (130).
[0012] The first center disk (150) has a circular-ring shaped first
disk contact surface (151a) that is disposed opposing an outer
surface (144)--of the two surfaces of the diaphragm (142)--located
on the compression-chamber (104) side of the valve case (103) and
that makes contact with the outer surface (144) when the oscillator
(130) is in the neutral position. The second center disk (160) has
a circular-ring shaped second disk contact surface (161a) that is
disposed opposing an inner surface (145)--of the two surfaces of
the diaphragm (142)--located on the oscillator (130) side, makes
contact with the inner surface (145) when the oscillator (130) is
in the neutral position, and has an outer diameter (D2b) set in the
range of 1.05-1.30 times an outer diameter (D1b) of the first disk
contact surface (151a). During reciprocating oscillation in the
intake direction and the discharge direction of the oscillator
(130), the diaphragm (142) centrally bends at a contact part (144a)
within the outer surface (144), with respect to the outer
circumference (P1) of the first disk contact surface (151a) of the
first center disk (150), and centrally bends at a contact part
(145a) within the outer surface (145), with respect to the outer
circumference (P2) of the second disk contact surface (161a) of the
second center disk (160).
[0013] According to the present configuration, because the outer
diameter of the first disk contact surface of the first center disk
and the outer diameter of the second disk contact surface of the
second center disk differ, the position in the radial direction of
the bent part of the outer surface of the diaphragm and the
position in the radial direction of the bent part of the inner
surface differ from one another during reciprocating oscillation in
the intake direction and the discharge direction the oscillator.
Accordingly, it is possible to prevent a local load concentration
from arising on the diaphragm during the reciprocating movement of
the oscillator, and therefore the service life of the diaphragm can
be prolonged. Furthermore, by embodying the relative relationship
between the outer diameter of the first disk contact surface and
the outer diameter of the second disk contact surface according the
above-mentioned numerical values, the first center disk located on
the compression chamber side of the valve case can be made smaller
than the second center disk located on the oscillator side and it
also becomes possible to keep the size of the second center disk
small.
[0014] In the electromagnetic-type pump (100) having the
above-mentioned configuration, the first center disk (150)
preferably has a first disk curved surface (152a) and the second
center disk (160) preferably has a second disk curved surface
(162a). The first disk curved surface (152a) extends from the outer
circumference of the first disk contact surface (151a) while
curving outward in the disk-radial direction with a prescribed
radius of curvature (R) and is formed in a ring shape in the disk
circumferential direction. The second disk curved surface (162a)
extends from the outer circumference of the second disk contact
surface (161a) while curving outward in the disk-radial direction
with the same radius of curvature (R) as that of the first disk
curved surface (152a) and is formed in a ring shape in the disk
circumferential direction.
[0015] According to the present configuration, in accordance with
the reciprocating oscillation in the intake direction and the
discharge direction of the oscillator, although the outer surface
of the diaphragm makes contact with a first disk curved surface of
the first center disk, when the inner surface of the diaphragm
makes contact with a second disk curved surface of the second
center disk, it is possible to prevent the diaphragm from bending
locally. Furthermore, the deflection of the diaphragm at this time
is the same, i.e., is balanced, on the first disk curved surface
side and the second disk curved surface side. As a result, it is
possible to prevent fatigue of the diaphragm from being biased
toward either the outer surface or the inner surface. In addition,
the first center disk, which has the first disk contact surface and
the first disk curved surface, can be made comparatively smaller
than the second center disk, which has the second disk contact
surface and the second disk curved surface, and it becomes possible
also to keep the size of the second center disk small.
[0016] It is noted that, in the above-mentioned explanation, to
assist with the understanding of the invention, symbols used in the
embodiments have been appended, in parentheses, to structural
elements of the invention such that the symbols correspond to the
embodiments; however, the configuration requirements of the
invention are not limited to the embodiments in which the symbols
are defined.
Effects of the Invention
[0017] According to the present invention as described above, in an
electromagnetic-type pump comprising a diaphragm coupled to an
electromagnetically driven oscillator, it becomes possible to
prolong the service life of the diaphragm and to achieve
compactness of the pump.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] FIG. 1 is a drawing that schematically shows the structure
of an electromagnetic-type pump of the present embodiment.
[0019] FIG. 2 is a drawing that shows an aspect during an intake
operation of the electromagnetic-type pump in FIG. 1.
[0020] FIG. 3 is a drawing that shows an aspect during a discharge
operation of the electromagnetic-type pump in FIG. 1.
[0021] FIG. 4 is a drawing, viewed from a drive-chamber side, of a
diaphragm part of the electromagnetic-type pump in FIG. 1.
[0022] FIG. 5 is a drawing that shows a cross-sectional structure
taken along line A-A of the diaphragm part in FIG. 4.
[0023] FIG. 6 is a drawing that shows an aspect during an intake
operation of the diaphragm part in FIG. 5.
[0024] FIG. 7 is a drawing that shows an aspect during a discharge
operation of the diaphragm part in FIG. 5.
MODE(S) FOR CARRYING OUT THE INVENTION
[0025] One embodiment of an electromagnetic-type pump of the
present invention is explained below, with reference to the
drawings. This electromagnetic-type pump is typically used as an
air pump for supplying air to water to be treated in a septic tank
or an air pump (also called a "blower") for supplying drive air to
an air-lift pump for transferring water to be treated in a septic
tank. It is noted that, in the drawings for explaining the
electromagnetic-type pump, an intake-movement direction (a first
direction) of an oscillator driven by electromagnetic forces is
indicated by arrow X1, and a discharge-movement direction (a second
direction that is a direction opposite that of the first direction)
of the oscillator is indicated by arrow X2.
[0026] As shown in FIG. 1, an electromagnetic-type pump 100
comprises a casing 101 that houses the structural elements of the
pump. Electromagnets 110, 120 and an oscillator 130 are housed in a
drive chamber 102 inside the casing 101. The electromagnet 110
comprises an electromagnetic coil 111, which is connected to an AC
power supply. Like the electromagnet 110, the electromagnet 120
comprises an electromagnetic coil 121, which is connected to the AC
power supply. The oscillator 130 comprises permanent magnets 131,
132. An end part of the oscillator 130 on the side opposite the
permanent magnets 131, 132 is coupled to a diaphragm part 140. When
the electromagnetic coil 111 and the electromagnetic coil 121 are
energized, the N pole and S pole positions of the electromagnet 110
and the electromagnet 120 respectively switch, and thereby driving
electromagnetic forces are imparted to the oscillator 130. Owing to
the attracting and repelling forces between the electromagnetic
forces at this time and the permanent magnets 131, 132 on the
oscillator 130 side, the oscillator 130 reciprocally oscillates in
the first direction X1 and the second direction X2 about a neutral
position shown in FIG. 1. The oscillator 130 corresponds to an
"oscillator" of the present invention.
[0027] The diaphragm part 140 comprises a main-body part 141, a
diaphragm 142, a first center disk 150, and a second center disk
160. The main-body part 141 is fixed to the casing 101. The
diaphragm 142 is a member composed of a rubber material, which is
one example of an elastic material. An outer-edge part 142a of the
diaphragm 142 is immovably attached to the main-body part 141. The
diaphragm 142 corresponds to a "diaphragm" of the present
invention.
[0028] The first center disk 150 and the second center disk 160 are
both members composed of a synthetic resin. The first center disk
150 is disposed on the opposite side of the oscillator 130 with the
diaphragm 142 interposed therebetween. The second center disk 160
is disposed on the opposite side of the first center disk 150,
sandwiching the diaphragm 142. The first center disk 150 and the
second center disk 160 are fixed to one another in the state in
which a central area of the diaphragm 142 is sandwiched, from both
surfaces, in a sheet-thickness direction of the diaphragm 142. The
oscillator 130 is coupled to both the first center disk 150 and the
second center disk 160. Consequently, the diaphragm 142 is
indirectly coupled to the oscillator 130 via the first center disk
150 and the second center disk 160. It is noted that, if the first
center disk 150 and the second center disk 160 are fixed to one
another, then the oscillator 130 should be fixed to at least one of
the first center disk 150 and the second center disk 160. The first
center disk 150 and the second center disk 160 herein correspond to
a "first center disk" and a "second center disk," respectively, of
the present invention.
[0029] A valve case 103 is attached on the opposite side of the
oscillator 130, sandwiching the diaphragm part 140 within the
casing 101. The valve case 103 comprises a compression chamber 104
and a discharge chamber 105. The compression chamber 104 is
provided on the opposite side of the oscillator 130, sandwiching
the diaphragm 142. The compression chamber 104 is a space for
sucking in air during movement in the first direction X1 (intake
direction) of the oscillator 130 and for compressing that air
during movement in the second direction X2 (discharge direction) of
the oscillator 130. The valve case 103 and the compression chamber
104 herein correspond to a "valve case" and a "compression
chamber," respectively, of the present invention.
[0030] An intake valve 170 is provided on a case-wall part 103a
that is interposed between the compression chamber 104 within the
valve case 103 and an exterior space 106. The intake valve 170 is
configured to open at a pressure-decreased time, which is when the
pressure in the compression chamber 104 has decreased, and to open
at a pressure-increased time, which is when the pressure in the
compression chamber 104 has increased. On the other hand, the
discharge chamber 105 is a space for discharging the air that has
been compressed by the compression chamber 104. A discharge valve
180 is provided on a case-wall part 103b, which is interposed
between the compression chamber 104 and the discharge chamber 105
of the valve case 103. The discharge valve 180 is configured to
close during a pressure-decreased time, which is when the pressure
in the compression chamber 104 has decreased, and to open during
pressure-increased time, which is when the pressure in the
compression chamber 104 has increased.
[0031] As shown in FIG. 2, when the oscillator 130 has moved in the
first direction X1 owing to the electromagnetic forces generated by
the electromagnets 110, 120, the diaphragm 142 is pulled in the
first direction X1 via the first center disk 150 and the second
center disk 160. Accordingly, the diaphragm 142 elastically deforms
such that the volume of the compression chamber 104 increases. At
this time, the pressure in the compression chamber 104 falls, the
intake valve 170 opens, and the discharge valve 180 closes.
Accordingly, air (outside air) from the exterior space 106 is
sucked into the compression chamber 104, which is at a relatively
low pressure, through the intake valve 170 in the valve-open
state.
[0032] As shown in FIG. 3, when the oscillator 130 has moved in the
second direction X2 owing to the electromagnetic forces generated
by the electromagnets 110, 120, the diaphragm 142 is pulled in the
second direction X2 via the first center disk 150 and the second
center disk 160. Accordingly, the diaphragm 142 elastically deforms
such that the volume of the compression chamber 104 decreases. At
this time, the pressure in the compression chamber 104 increases,
the intake valve 170 closes, and the discharge valve 180 opens.
Accordingly, the air in the compression chamber 104 is discharged
to the discharge chamber 105 through the discharge valve 180 in the
valve-open state.
[0033] Here, the details of the diaphragm part 140 having the
above-mentioned configuration will be explained, with reference to
FIG. 4 to FIG. 7.
[0034] As shown in FIG. 4, the diaphragm 142 is configured in a
discoidal manner. The diaphragm 142 has an opening 143 in its
central area; an opening-edge part 143a of the opening 143 is
sandwiched by the first center disk 150 and the second center disk
160. The first center disk 150 and the second center disk 160 are
both configured in a discoidal manner and concentric with the
diaphragm 142.
[0035] As shown in FIG. 5, the first center disk 150 has a through
hole 150a in its central portion. Likewise, the second center disk
160 has a through hole 160a in its central portion. An end part of
the oscillator 130 on the diaphragm part 140 side comprises a
coupling shaft 130a. The coupling shaft 130a is screwed into a
fixing means 133, such as a nut, in the state in which the coupling
shaft 130a is inserted into both the through hole 150a of the first
center disk 150 and the through hole 160a of the second center disk
160. As a result, the oscillator 130 is fixed to the diaphragm 142
via the first center disk 150 and the second center disk 160.
[0036] The first center disk 150 is disposed opposing an outer
surface 144--of the two surfaces of the diaphragm 142--on the
compression chamber 104 side of the valve case 103. To clamp and
hold the central area of the diaphragm 142 in cooperation with the
second center disk 160, the first center disk 150 comprises a
discoidal center part 151, which is centered on the through hole
150a, and a circular-ring shaped outer-circumference part 152,
which is located on the outer side in the disk radial direction of
the center part 151.
[0037] The center part 151 has a first disk contact surface 151a.
The first disk contact surface 151a is a circular-ring shaped
contact surface that makes continuous contact with the outer
surface 144 of the diaphragm 142 when the oscillator 130 is in the
neutral position. The first disk contact surface 151a corresponds
to a "first disk contact surface" of the present invention. The
"neutral position" referred to herein is the position of the
oscillator 130 when the diaphragm 142 is in the initial state, in
which the diaphragm 142 is not elastically deformed toward either
the intake side (the left side in the drawings) or the discharge
side (the right side in the drawings), as shown in FIG. 1 and FIG.
5.
[0038] The outer-circumference part 152 has a first disk curved
surface 152a. The first disk curved surface 152a extends from a
first circle P1 (hereinbelow, also called an "outer circumference
P1 of the first disk contact surface 151a"), which defines an outer
circumference of the first disk contact surface 151a, while curving
outward in the disk-radial direction with a prescribed radius of
curvature R and while increasing its spacing from the outer surface
144 of the diaphragm 142; it is formed in a ring shape in the disk
circumferential direction. That is, the first circle P1 forms a
boundary line that determines a boundary between the first disk
contact surface 151a of the center part 151 and the first disk
curved surface 152a of the outer-circumference part 152. The first
disk curved surface 152a corresponds to a "first disk curved
surface" of the present invention.
[0039] Like the first center disk 150, the second center disk 160
is disposed opposing an inner surface 145--of the two surfaces of
the diaphragm 142--on the oscillator 130 side. To clamp and hold
the central area of the diaphragm 142 in cooperation with the first
center disk 150, the second center disk 160 comprises a discoidal
center part 161, which is centered on the through hole 160a, and a
circular-ring shaped outer-circumference part 162, which is located
on the outer side in the disk-radial direction of the center part
161.
[0040] The center part 161 has a second disk contact surface 161a.
The second disk contact surface 161a is a circular-ring shaped
contact surface that makes continuous contact with the inner
surface 145 of the diaphragm 142 when the oscillator 130 is in the
neutral position discussed above. The second disk contact surface
161a corresponds to a "second disk contact surface" of the present
invention.
[0041] The outer-circumference part 162 has a second disk curved
surface 162a. The second disk curved surface 162a extends from a
second circle P2 (hereinbelow, also called an "outer circumference
P2 of the second disk contact surface 161a"), which defines an
outer circumference of the second disk contact surface 161a, while
curving outward in the disk-radial direction with the
abovementioned radius of curvature R (a radius of curvature the
same as that of the first disk curved surface 152a) and while
increasing its spacing from the inner surface 145 of the diaphragm
142; it is formed in a ring shape in the disk circumferential
direction. That is, the second circle P2 forms a boundary line that
determines the boundary between the second disk contact surface
161a of the center part 161 and the second disk curved surface 162a
of the outer-circumference part 162. The second disk curved surface
162a corresponds to a "second disk curved surface" of the present
invention.
[0042] In the diaphragm part 140 of the present embodiment, when
the first center disk 150 and the second center disk 160 are
compared, it can be seen that these disks are configured such that
they have asymmetric shapes. The disk diameter D2a (outer diameter)
of the second center disk 160 is configured such that it is larger
than the disk diameter D1a (outer diameter) of the first center
disk 150. In addition, in the diaphragm part 140, the outer
diameter D2b of the second disk contact surface 161a (i.e., the
"outer diameter of the center part 161" or the "diameter of the
second circle P2") of the second center disk 160 is configured such
that it is larger than the outer diameter D1b of the first disk
contact surface 151a (i.e., the "outer diameter of the center part
151" or the "diameter of the first circle P1") of the first center
disk 150. In particular, in the diaphragm part 140, the outer
diameter D2b of the second disk contact surface 161a is set such
that it lies in the range of 1.05-1.30 times the outer diameter D1b
of the first disk contact surface 151a. That is, with regard to the
relationship between the outer diameter D1b and the outer diameter
D2b, the correlation expression
D2b=1.05.times.D1b.about.1.30.times.D1b holds true. The outer
diameter D1b of the first disk contact surface 151a and the outer
diameter D2b of the second disk contact surface 161a are both
"clamping diameters" for clamping and holding the outer diameter
D2b of the diaphragm 142.
[0043] As shown in FIG. 6, when the oscillator 130 moves in the
intake direction (the first direction X1), the outer surface 144 of
the diaphragm 142 of the diaphragm part 140 having the
above-mentioned configuration is depressed in the first direction
X1 by the first center disk 150, and the inner surface 145 is
pulled in the first direction X1 by the second center disk 160. At
this time, the outer surface 144 of the diaphragm 142 centrally
bends at a contact part 144a, with respect to the outer
circumference P1 of the first disk contact surface 151a, and
elastically deforms such that it becomes depressed on the first
direction X1 side. In addition, the inner surface 145 of the
diaphragm 142 centrally bends at a contact part 145a, with respect
to the outer circumference P2 of the second disk contact surface
161a, and elastically deforms such that it becomes depressed toward
the first direction X1 side. Furthermore, if the oscillator 130 has
moved in the first direction X1 until the outer surface 144 of the
diaphragm 142 makes contact with the first disk curved surface 152a
of the first center disk 150, then localized bending of the
diaphragm 142 is prevented by virtue of the outer surface 144
making surface contact with the first disk curved surface 152a.
[0044] On the other hand, as shown in FIG. 7, when the oscillator
130 moves in the discharge direction (the second direction X2), the
inner surface 145 of the diaphragm 142 of the diaphragm part 140
having the above-mentioned configuration is depressed in the second
direction X2 by the second center disk 160, and the outer surface
144 is pulled in the second direction X2 by the first center disk
150. At this time, the inner surface 145 of the diaphragm 142
centrally bends at the contact part 145a, with respect to the outer
circumference P2 of the second disk contact surface 161a, and
elastically deforms such that it becomes depressed on the second
direction X2 side. In addition, the outer surface 144 of the
diaphragm 142 centrally bends at the contact part 144a, with
respect to the outer circumference P1 of the first disk contact
surface 151a, and elastically deforms such that it becomes
depressed on the second direction X2 side. Furthermore, if the
oscillator 130 has moved in the second direction X2 until the inner
surface 145 of the diaphragm 142 makes contact with the second disk
curved surface 162a of the second center disk 160, then localized
bending of the diaphragm 142 is prevented by virtue of the inner
surface 145 making surface contact with the second disk curved
surface 162a.
[0045] According to an electromagnetic-type pump 100 having the
above-mentioned configuration, as a result of the reciprocating
oscillation of the oscillator 130 in the intake direction and the
discharge direction being performed repetitively, a load
concentrates at the contact part 144a on the outer surface 144 of
the diaphragm 142 and a load concentrates at the contact part 145a
on the inner surface 145 of the diaphragm 142. At this time,
because the outer diameter D1b of the first disk contact surface
151a of the first center disk 150 and the outer diameter D2b of the
second disk contact surface 161a of the second center disk 160
differ, the position in the radial direction of the bent part of
the outer surface 144 of the diaphragm 142 and the position in the
radial direction of the bent part of the inner surface 145 of the
diaphragm 142 differ from one another. Accordingly, it is possible
to prevent a local load concentration from arising on the diaphragm
142 during the reciprocating movement of the oscillator 130, and
therefore the service life of the diaphragm 142 can be
prolonged.
[0046] Furthermore, by defining the relationship between the outer
diameter D1b of the first disk contact surface 151a and the outer
diameter D2b of the second disk contact surface 161a with the
correlation expression of D2b=1.05.times.D1b.about.1.30.times.D1b,
the first center disk 150 located on the compression chamber 104
side of the valve case 103, that is, the center disk located on the
outer side, can be made smaller than the second center disk 160
located on the oscillator 130 side and it also becomes possible to
keep the size of the second center disk 160 small. As a result, it
becomes possible to make the electromagnetic-type pump 100 compact.
It is noted that if the outer diameter D2b is less than 1.05 times
the outer diameter D1b, then the position in the radial direction
of the bent part on the outer surface 144 of the diaphragm 142 and
the position in the radial direction of the bent part on the inner
surface 145 become too close, and consequently the effect of
prolonging the service life of the diaphragm 142 becomes small. In
addition, if the outer diameter D2b is greater than 1.30 times the
outer diameter D1b, then the size of the second center disk 160
becomes large compared with the size of the first center disk 150,
which is disadvantageous for making the electromagnetic-type pump
100 compact. Accordingly, in the present embodiment, by setting the
sizes of the first disk contact surface 151a and the second disk
contact surface 161a such that they satisfy the above-mentioned
correlational expression, the effect of prolonging the service life
of the diaphragm 142 and the effect of making the
electromagnetic-type pump 100 compact can be achieved
simultaneously.
[0047] In addition, because the first disk curved surface 152a of
the first center disk 150 and the second disk curved surface 162a
of the second center disk 160 have the same radius of curvature R,
the deflection of the diaphragm 142 is the same, i.e., balanced, on
the first disk curved surface 152a side and the second disk curved
surface 162a side. As a result, although the outer surface 144 of
the diaphragm 142 makes contact with the first disk curved surface
152a of the first center disk 150, fatigue of the diaphragm 142 can
be prevented from being biased toward either the outer surface 144
or the inner surface 145 when the inner surface 145 of the
diaphragm 142 makes contact with the second disk curved surface
162a of the second center disk 160.
[0048] The present invention is not limited to only the
representative embodiments mentioned above, and various
applications and modifications are conceivable as long as they do
not depart from the object of the present invention. For example,
each of the following modes in which the above-mentioned
embodiments are applied can also be implemented.
[0049] In the above-mentioned embodiments, a case is described in
which the first disk curved surface 152a of the first center disk
150 and the second disk curved surface 162a of the second center
disk 160 have the same radius of curvature R; however, a
configuration can be utilized in which the radius of curvature of
the first disk curved surface 152a differs from the radius of
curvature of the second disk curved surface 162a.
[0050] In the above-mentioned embodiments, a case is described in
which the first center disk 150 comprises the outer-circumference
part 152 (the first disk curved surface 152a) and the second center
disk 160 comprises the outer-circumference part 162 (the second
disk curved surface 162a); however, it is also possible to omit at
least one of the outer-circumference part 152 and the
outer-circumference part 162.
[0051] In the above-mentioned embodiments, a case is described in
which the disk diameter D2a of the second center disk 160 is larger
than the disk diameter D1a of the first center disk 150; however,
the disk diameter D1a and the disk diameter D2a may coincide.
[0052] In the above-mentioned embodiments, an electromagnetic-type
pump 100 is described in which the diaphragm part 140 is coupled to
only one-end part of the oscillator 130; however, it is also
possible to utilize an electromagnetic-type pump in which the
diaphragm part 140 is coupled to both end parts of the oscillator
130.
[0053] In the above-mentioned embodiments, an electromagnetic-type
pump 100 is described in which the intake movement and the
discharge movement of air are performed, which is one type of
fluid; however, it is also possible to utilize an
electromagnetic-type pump that manipulates gases other than air,
liquids, etc. For example, a fuel-cell unit that produces
electricity by the chemical reaction of hydrogen and oxygen
comprises a gas-supply pump that supplies a gas (municipal gas, LP
gas) to a fuel reforming apparatus for extracting hydrogen, and the
structure of the above-mentioned electromagnetic-type pump 100 can
also be utilized in this gas-supply pump.
* * * * *