U.S. patent application number 11/141384 was filed with the patent office on 2005-12-01 for fluid coupling.
This patent application is currently assigned to NISSAN MOTOR CO., LTD.. Invention is credited to Kamada, Seiji, Kumagai, Hiroshi.
Application Number | 20050263198 11/141384 |
Document ID | / |
Family ID | 34937105 |
Filed Date | 2005-12-01 |
United States Patent
Application |
20050263198 |
Kind Code |
A1 |
Kamada, Seiji ; et
al. |
December 1, 2005 |
Fluid coupling
Abstract
A pulsation absorber is provided in a fluid channel formed in a
body of a fluid coupling. Fluid flows through the fluid channel in
an assembled state. The pulsation absorber is arranged to deform in
a same direction as the fluid to flow in the fluid channel
pulsates. The pulsation absorber thereby absorbs pulsation of the
fluid.
Inventors: |
Kamada, Seiji; (Yokohama,
JP) ; Kumagai, Hiroshi; (Kanagawa, JP) |
Correspondence
Address: |
FOLEY AND LARDNER
SUITE 500
3000 K STREET NW
WASHINGTON
DC
20007
US
|
Assignee: |
NISSAN MOTOR CO., LTD.
|
Family ID: |
34937105 |
Appl. No.: |
11/141384 |
Filed: |
June 1, 2005 |
Current U.S.
Class: |
138/30 ;
123/447 |
Current CPC
Class: |
F02M 55/04 20130101;
F02M 37/0041 20130101; Y10T 29/49826 20150115; F16L 55/053
20130101 |
Class at
Publication: |
138/030 ;
123/447 |
International
Class: |
F16L 055/04 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 1, 2004 |
JP |
2004-163141 |
Claims
What is claimed is:
1. A fluid coupling comprising: a body formed with a fluid channel;
and a pulsation absorber provided in the fluid channel, and
arranged to deform in a same direction as fluid to flow in the
fluid channel pulsates, and thereby to absorb pulsation of the
fluid.
2. The fluid coupling as claimed in claim 1, wherein the pulsation
absorber is provided at a first part of the fluid channel, and the
first part of the fluid channel has a section smaller than a
section of a second part of the fluid channel.
3. A fluid coupling comprising: a pulsation absorber provided in a
fluid channel, and arranged to absorb pulsation of fluid to flow in
the fluid channel, the pulsation absorber including: a bellows
formed by resin or rubber; and an elastic member provided inside
the bellows, including a molded member formed by resin or rubber,
and arranged to deform elastically together with the bellows.
4. A fluid coupling comprising: a body formed with a fluid channel
of a straight type, and a damping chamber branching off from the
fluid channel; and a pulsation absorber provided in the damping
chamber, and arranged to absorb pulsation of fluid to flow in the
fluid channel.
5. The fluid coupling as claimed in claim 4, wherein the pulsation
absorber includes a diaphragm formed by resin or rubber, and an
elastic member arranged to deform elastically in conjunction with
deformation of the diaphragm.
6. The fluid coupling as claimed in claim 1, wherein the pulsation
absorber includes a bellows formed by resin or rubber.
7. The fluid coupling as claimed in claim 6, wherein the pulsation
absorber includes an elastic member provided inside the bellows,
and arranged to deform elastically together with the bellows.
8. The fluid coupling as claimed in claim 7, wherein the elastic
member includes at least one of a molded member formed by resin or
rubber and a coil spring.
9. The fluid coupling as claimed in claim 3, wherein the molded
member is resin or rubber containing numerous bubbles.
10. The fluid coupling as claimed in claim 8, further comprising a
support fixed in the fluid channel, wherein the pulsation absorber
is supported by the support.
11. The fluid coupling as claimed in claim 3, wherein the fluid
coupling is an elbow type including an elbow portion and an
extension portion extending from the elbow portion, the extension
portion having an open end opening in opposite direction from the
elbow portion; and the fluid coupling further comprises a support
fixed to the open end of the extension portion, wherein the
pulsation absorber is supported by the support in the extension
portion.
12. The fluid coupling as claimed in claim 11, wherein the support
is formed with an air hole arranged to expose an inside part of the
bellows to open air.
13. The fluid coupling as claimed in claim 3, wherein the molded
member is formed in a cylindrical form, and is provided coaxially
with the bellows.
14. The fluid coupling as claimed in claim 3, wherein the molded
member is a hollow-molded member formed in a bellows form.
15. The fluid coupling as claimed in claim 3, wherein the molded
member is formed in a thin cylindrical form; and the elastic member
further includes a coil spring disposed concentrically outside the
molded member.
16. The fluid coupling as claimed in claim 3, wherein the molded
member is a composite-molded member including a coil spring
insert-molded in the resin or rubber forming the molded member.
17. A fluid coupling comprising: means for passing fluid; and means
for absorbing pulsation of the fluid by deforming in a same
direction as the fluid pulsates.
Description
BACKGROUND OF THE INVENTION
[0001] The present invention generally relates to a fluid coupling,
and more particularly, to a fluid coupling for use in a fuel supply
system of a vehicle.
[0002] Japanese Patent Application Publication No. H09(1997)-195885
discloses a fuel supply system of a fuel returnless type.
SUMMARY OF THE INVENTION
[0003] It is an object of the present invention to provide a fluid
coupling capable of damping pulsation of fluid effectively, while
using a limited space and being small in size and low in cost.
[0004] According to one aspect of the present invention, a fluid
coupling includes: a body formed with a fluid channel; and a
pulsation absorber provided in the fluid channel, and arranged to
deform in a same direction as fluid to flow in the fluid channel
pulsates, and thereby to absorb pulsation of the fluid.
[0005] The other objects and features of this invention will become
understood from the following description with reference to the
accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] FIG. 1 is a sectional view showing a fluid coupling
according to an embodiment of the present invention.
[0007] FIG. 2 is a sectional view showing a fluid coupling
according to another embodiment of the present invention.
[0008] FIG. 3 is a sectional view showing a pulsation absorber
applicable to the fluid coupling, according to still another
embodiment of the present invention.
[0009] FIG. 4 is a sectional view showing a pulsation absorber
applicable to the fluid coupling, according to still another
embodiment of the present invention.
[0010] FIG. 5 is a sectional view showing a pulsation absorber
applicable to the fluid coupling, according to still another
embodiment of the present invention.
[0011] FIG. 6 is a sectional view showing a pulsation absorber
applicable to the fluid coupling, according to still another
embodiment of the present invention.
[0012] FIG. 7 is a sectional view showing a pulsation absorber
applicable to the fluid coupling, according to still another
embodiment of the present invention.
[0013] FIG. 8 is a sectional view showing a fluid coupling
according to still another embodiment of the present invention.
[0014] FIG. 9 is a sectional view showing a pulsation absorber
applicable to the fluid coupling of FIG. 8, according to still
another embodiment of the present invention.
[0015] FIG. 10 is a diagram showing a fuel supply system of a
return type.
[0016] FIG. 11 is a diagram showing a fuel supply system of a
returnless (non-return) type.
DETAILED DESCRIPTION OF THE INVENTION
[0017] First, in order to facilitate understanding of the present
invention, a description will be given of fuel supply systems for a
vehicle. FIG. 10 is a diagram showing a fuel supply system of a
return type. In this fuel supply system, fuel is supplied from a
fuel tank (not shown in FIG. 10) via an underfloor supply line 101
and a supply tube 102 to a delivery pipe 103. Then, the fuel is
supplied from delivery pipe 103 to fuel injectors 104 of each
cylinder. Delivery pipe 103 is equipped with a pressure regulator
105. Pressure regulator 105 maintains constant pressure in delivery
pipe 103 by returning surplus fuel via a return tube 106 and an
underfloor return line 107 to the fuel tank.
[0018] FIG. 11 is a diagram showing a fuel supply system of a
returnless (non-return) type. In this fuel supply system, fuel is
supplied from a fuel tank (not shown in FIG. 11) via underfloor
supply line 101 and supply tube 102 to delivery pipe 103. Then, the
fuel is supplied from delivery pipe 103 to fuel injectors 104.
Delivery pipe 103 is equipped with a pulsation damper 108.
Pulsation damper 108 damps pulsation, and noise of pulsation, of
the fuel which originate from a discharging action of a fuel pump
or a fuel injection action of fuel injectors 104.
[0019] In the fuel supply system of FIG. 10, fluid couplings or
quick connectors 110 are each provided between supply line 101 and
supply tube 102, between supply tube 102 and delivery pipe 103,
between pressure regulator 105 and return tube 106, and between
return tube 106 and return line 107. In the fuel supply system of
FIG. 11, fluid couplings 110 are each provided between supply line
101 and supply tube 102, and between supply tube 102 and delivery
pipe 103. Generally, each of fluid couplings 110, straight type or
elbow type, is made of metal and/or resin, and includes one or two
O rings in a joining portion.
[0020] Recently, improvements have been required for vehicles to be
reduced further in weight and cost. Therefore, such vehicles have
employed an increasing number of fuel supply systems of the
returnless type which has a smaller number of elements than the
return type.
[0021] However, in the fuel supply system of the returnless type,
pulsation of the fuel is likely to occur on the part of delivery
pipe 103, compared with the return type. For this reason, delivery
pipe 103 of the returnless type is equipped with pulsation damper
108. Therefore, the fuel supply system of the returnless type
requires an attaching portion, such as a flange, for joining
pulsation damper 108 to delivery pipe 103, and an arrangement for
sealing the joining part. Thus, the fuel supply system of the
returnless type may have a complex structure, and cannot easily be
reduced in cost. Besides, such fuel supply system of the returnless
type cannot easily be laid out in a small space in an engine
room.
[0022] FIG. 1 is a sectional view showing a fluid coupling A1
according to an embodiment of the present invention. Each of fluid
couplings (or quick connectors) of the following embodiments is
applicable to joint between supply tube 102 (a resin tube T) and
delivery pipe 103 (a metal pipe P) in the fuel supply system of the
returnless type of FIG. 11. However, the fluid couplings are not
limited to the following embodiments in positioning and detailed
structure, and may be applicable as modifications and variations of
such embodiments.
[0023] Fluid coupling A1 of FIG. 1 is a straight type, and includes
one or first joining portion J1, and the other or second joining
portion J2 provided integrally with first joining portion J1. First
joining portion J1 and second joining portion J2 form a body of
fluid coupling A1. First joining portion J1 includes two O rings 1
and a back-up ring 2. O rings 1 and back-up ring 2 are attached to
an inside surface of first joining portion J1. Second joining
portion J2 includes a projecting portion 3. Projecting portion 3
for retaining a tube is formed on an outer circumference of second
joining portion J2. Metal pipe P (delivery pipe) and resin tube T
(supply tube) are connected with first joining portion J1 and
second joining portion J2, respectively, in an assembled state.
Specifically, metal pipe P together with a spacer 4 is fit into
first joining portion J1, and resin tube T is fit over second
joining portion J2. Fuel which is fluid flows through fluid
coupling A1 in the assembled state.
[0024] The body of fluid coupling A1 is formed by material
resistant to fuel. In this example, the body of fluid coupling A1
is formed by material composed mainly of a resin selected from a
group consisting of polyamide, polyolefin, polysulfide,
fluorocarbon resin, polyester, polyacetal and polyketone.
[0025] The body of fluid coupling A1 is formed with a fluid channel
5 extending through the body of fluid coupling A1. Fluid coupling
A1 includes a support 6, and a pulsation absorber provided in fluid
channel 5. The pulsation absorber of this embodiment is a bellows
7. Specifically, support 6 is fixed in fluid channel 5, and bellows
7 is supported by support 6. Pulsation absorber or bellows 7 is
arranged to deform in a same direction as fluid to flow in fluid
channel 5 pulsates, and thereby absorb the pulsation of the fluid.
A part or first part of fluid channel 5 at which bellows 7 is
provided has a section smaller than a section of other part or
second part of fluid channel 5.
[0026] Support 6 is formed by material of the same kind as the
material forming the body of fluid coupling A1. In this example,
support 6 is formed by material composed mainly of glass fiber
reinforced polyamide 12. Support 6 is formed with at least one
opening to pass the fluid through the opening. Support 6 is fixed
to the body of fluid coupling A1 by rotary welding.
[0027] Bellows 7 is formed by resin or rubber. In this example,
bellows 7 is formed by polyamide 12, and molded by blow molding.
Bellows 7 is joined to support 6 air-tightly by welding, and is
arranged to act as an air spring. Besides the above-mentioned
polyamide 12, bellows 7 may be formed by a thermoplastic resin,
such as a polyamide-based thermoplastic resin, a polyolefin-based
thermoplastic resin, a fluorocarbon-based thermoplastic resin, a
polyester-based thermoplastic resin, or a polysulfide-based
thermoplastic resin. Bellows 7 may also be formed by a
thermoplastic elastomer, or a rubber, such as a fluorocarbon-based
rubber, a nitrile-based rubber, or an acrylic-based rubber.
[0028] In fluid coupling A1 of this embodiment, pulsation absorber
or bellows 7 is provided in fluid channel 5, and is arranged to
deform in the same direction as the pulsation of the fluid to flow
in fluid channel 5, and thereby absorb the pulsation of the fluid
effectively. Thus, pulsation absorber or bellows 7 confronts a
propagation direction of the pulsation of the fluid, in an
assembled state in the fuel supply system or fluid delivery system.
Specifically, in the fuel supply system, when the fuel is supplied
from the fuel tank to metal pipe P, and pulsation of the fuel
originating from the fuel injection action of fuel injectors 104
occurs on the part of metal pipe P, bellows 7 confronting the
propagation direction of the pulsation deforms springily or
elastically, or expand and contract, to absorb the pulsation of the
fuel effectively.
[0029] Thus, fluid coupling A1 of this embodiment includes
pulsation absorber or bellows 7 provided in fluid channel 5. Hence,
fluid coupling A1 of this embodiment does not require an additional
space for a pulsation absorber. In fluid channel 5, pulsation
absorber or bellows 7 is arranged to act as air spring. Therefore,
fluid coupling A1 has a simple structure having a small size and a
small number of elements, and is capable of damping the pulsation
of the fluid occurring in the fuel supply system. With fluid
coupling A1 of this embodiment, the fuel supply system of the
returnless type of FIG. 11 can have a structure without pulsation
damper 108, and thus can be reduced in weight and cost, and can be
easily laid out in a limited space in an engine room.
[0030] Besides, pulsation absorber or bellows 7 of fluid coupling
A1 of this embodiment is formed by resin or rubber. Thus, bellows 7
is light in weight and low in cost, and has a property of deforming
efficiently to absorb the pulsation of the fluid effectively.
Additionally, since resin or rubber exhibits an excellent
formability, bellows 7 can be formed easily to have a desired
spring constant.
[0031] Further, support 6 of fluid coupling A1 of this embodiment
is fixed to the body of fluid coupling A1 by rotary welding, and
bellows 7 is joined to support 6 by welding. Thus, these elements
can be joined to one another easily and securely without using
joining parts. Therefore, the structure of fluid coupling A1 can be
further simplified and reduced in weight.
[0032] Besides, fluid coupling A1 of this embodiment may be
applicable between supply line 101 and supply tube 102 in the fuel
supply system of the returnless type of FIG. 11. In this case,
supply line 101 may be connected with first joining portion J1, and
bellows 7 can absorb pulsation of the fuel which originates from
the discharging action of the fuel pump.
[0033] Further, fluid coupling A1 of this embodiment is formed with
fluid channel 5, and the section of the part of fluid channel 5 at
which bellows 7 is provided is smaller than the section of the
other part of fluid channel 5. The thus-narrowed part of fluid
channel 5 acts as an orifice, and thereby is capable of reducing
the propagation of the pulsation of the fuel.
[0034] FIG. 2 is a sectional view showing a fluid coupling A2
according to another embodiment of the present invention. Elements
in FIG. 2 that are identical or equivalent to the elements shown in
FIG. 1 are indicated by the same reference marks, and may not be
described in detail in this part of description.
[0035] Fluid coupling A2 of FIG. 2 is an elbow type, and includes
first joining portion J1, and second joining portion J2 provided
integrally with first joining portion J1. Second joining portion J2
is arranged substantially orthogonal to first joining portion J1 so
that first joining portion J1 and second joining portion J2 form an
elbow portion. Fluid coupling A2 also includes an extension portion
E extending from the elbow portion coaxially with first joining
portion J1. Extension portion E has an open end opening in the
coaxial direction or opposite direction from the elbow portion, and
includes a support 11, and a pulsation absorber arranged to absorb
pulsation of fluid to flow in fluid channel 5 in an assembled
state.
[0036] Support 11 of this embodiment is a plate member formed by
glass fiber reinforced polyamide 12. The pulsation absorber of this
embodiment is attached to support 11, and support 11 is fixed to
the open end of extension portion E by rotary welding so as to
block up the open end of extension portion E.
[0037] The pulsation absorber of this embodiment includes bellows 7
and an elastic member. Bellows 7 of this embodiment is formed by
resin or rubber, as in the foregoing embodiment. The elastic member
of this embodiment is provided inside bellows 7, and is arranged to
deform springily or elastically, or expand and contract, together
with bellows 7. The elastic member of this embodiment is a molded
member 12 formed by resin or rubber. Molded member 12 of this
embodiment is made of fluoro rubber compression-molded in a
cylindrical form, and is provided coaxially with bellows 7.
[0038] Besides the above-mentioned fluoro rubber, molded member 12
may be made of rubber of various types, such as nitrile rubber,
acrylic rubber, silicone rubber, fluorinated silicone rubber,
hydrin rubber, urethane rubber, ethylene-propylene rubber, or butyl
rubber. Molded member 12 may also be made of resin of various
types, such as polyolefin, polysulfide, fluorocarbon resin,
polyester, polyacetal, polyketone, polyvinyl chloride, or
thermoplastic elastomer.
[0039] Thus, in fluid coupling A2 of this embodiment, the pulsation
absorber is composed of bellows 7 and molded member 12 arranged to
act respectively as air spring and a rubber spring by deforming
springily or elastically, or expanding and contracting together.
Additionally, bellows 7 and molded member 12 each formed by resin
or rubber exhibit high damping effects. Therefore, the pulsation
absorber of this embodiment can absorb the pulsation of the fluid
highly effectively even when pressure of the fluid is relatively
high.
[0040] Besides, since the pulsation absorber of this embodiment is
composed of bellows 7 and molded member 12 each formed by resin or
rubber, the pulsation absorber can be formed to have a desired
spring constant with an increased degree of freedom, and thereby
can adapt to various intensities of pressure and pressure pulsation
in the fluid. Additionally, fluid coupling A2 of this embodiment
has a simple structure having a small size and a small number of
elements, as in the foregoing embodiment, and the fuel supply
system adopting fluid coupling A2 of this embodiment can be reduced
in weight and cost, and can be easily laid out in a limited space
in an engine room.
[0041] FIG. 3 is a sectional view showing a pulsation absorber
applicable to the fluid coupling, according to still another
embodiment of the present invention. The pulsation absorber of FIG.
3 includes bellows 7 and an elastic member. Bellows 7 is formed by
resin or rubber. The elastic member of this embodiment is provided
inside bellows 7, and is arranged to deform springily or
elastically, or expand and contract, together with bellows 7. The
elastic member of this embodiment includes a hollow-molded member
13. Hollow-molded member 13 is formed by resin or rubber in a
bellows form.
[0042] FIG. 4 is a sectional view showing a pulsation absorber
applicable to the fluid coupling, according to still another
embodiment of the present invention. The pulsation absorber of FIG.
4 includes bellows 7 and an elastic member. Bellows 7 is formed by
resin or rubber. The elastic member of this embodiment is provided
inside bellows 7, and is arranged to deform springily or
elastically, or expand and contract, together with bellows 7. The
elastic member of this embodiment includes a foam-molded member 14.
Foam-molded member 14 is formed by resin or rubber containing
numerous bubbles, and shaped in a cylindrical form.
[0043] FIG. 5 is a sectional view showing a pulsation absorber
applicable to the fluid coupling, according to still another
embodiment of the present invention. The pulsation absorber of FIG.
5 includes bellows 7 and an elastic member. Bellows 7 is formed by
resin or rubber. The elastic member of this embodiment is provided
inside bellows 7, and is arranged to deform springily or
elastically, or expand and contract, together with bellows 7. The
elastic member of this embodiment includes molded member 12. Molded
member 12 is formed by resin or rubber in a cylindrical form.
Support 11 of this embodiment is formed with an air hole 11a
exposing an inside part of bellows 7 to open air. When bellows 7
undergoes load of the pulsation of the fluid, bellows 7 takes air
in and out of the inside part via air hole 11a. Therefore, the
pulsation absorber of this embodiment can obtain increased damper
effects.
[0044] FIG. 6 is a sectional view showing a pulsation absorber
applicable to the fluid coupling, according to still another
embodiment of the present invention. The pulsation absorber of FIG.
6 includes bellows 7 and an elastic member. Bellows 7 is formed by
resin or rubber. The elastic member of this embodiment is provided
inside bellows 7, and is arranged to deform springily or
elastically, or expand and contract, together with bellows 7. The
elastic member of this embodiment includes a molded member 15 and a
coil spring 16. Molded member 15 is formed by resin or rubber in a
thin cylindrical form. Coil spring 16 is disposed concentrically
outside molded member 15.
[0045] FIG. 7 is a sectional view showing a pulsation absorber
applicable to the fluid coupling, according to still another
embodiment of the present invention. The pulsation absorber of FIG.
7 includes bellows 7 and an elastic member. Bellows 7 is formed by
resin or rubber. The elastic member of this embodiment is provided
inside bellows 7, and is arranged to deform springily or
elastically, or expand and contract, together with bellows 7. The
elastic member of this embodiment includes a composite-molded
member 17. Composite-molded member 17 includes coil spring 16
insert-molded in resin or rubber.
[0046] The pulsation absorbers of FIGS. 3.about.7 are applicable to
fluid couplings A1 and A2 of FIGS. 1 and 2, and are capable of
obtain similar effects and advantages as in the foregoing
embodiments. Especially, the pulsation absorber composed of bellows
7 and at least one of the molded members and the coil spring can be
formed to have a desired spring constant with a further increased
degree of freedom.
[0047] The pulsation absorbers of FIGS. 3 and 5.about.7 may use a
foam-molded member as shown in FIG. 4 in place of each of the
molded members of FIGS. 3 and 5.about.7. In each case, the
pulsation absorbers can obtain a desired spring constant by varying
foaming rates of the foam-molded member. Besides, each of the
molded members may be impregnated with fluid such as oil, and
thereby can be formed to have an adjusted ability to absorb the
pulsation while being prevented from deterioration. Additionally,
air hole 11a of support 11 of FIG. 5 is applicable to the foregoing
embodiments and the following embodiments.
[0048] FIG. 8 is a sectional view showing a fluid coupling A3
according to still another embodiment of the present invention.
Elements in FIG. 8 that are identical or equivalent to the elements
shown in FIGS. 1 and 2 are indicated by the same reference marks,
and may not be described in detail in this part of description.
[0049] Fluid coupling A3 of FIG. 8 is a straight type, and includes
first joining portion J1, and second joining portion J2 provided
integrally with first joining portion J1. The body of fluid
coupling A3 is formed integrally with a damping chamber F. Damping
chamber F is located at a middle part of the body and branches off
from fluid channel 5. Fluid coupling A3 of this embodiment includes
pulsation absorber disposed in damping chamber F, and arranged to
absorb pulsation of fluid to flow in fluid channel 5 in an
assembled state. The pulsation absorber of this embodiment is
bellows 7.
[0050] Damping chamber F communicates with fluid channel 5 via a
communicating passage 8, and is formed with an open end opening in
opposite direction from communicating passage 8. Communicating
passage 8 is formed narrower than fluid channel 5, or is formed to
have an internal sectional size smaller than fluid channel 5.
Bellows 7 is attached to support 11, and support 11 is fixed to the
open end of damping chamber F, as in the foregoing embodiment.
[0051] Thus, fluid coupling A3 of this embodiment is arranged to
absorb the pulsation of the fluid effectively by bellows 7
deforming, or expanding and contracting, springily or elastically,
and damping chamber F acting as a Helmholtz resonating chamber.
Damping chamber F branches off perpendicularly from fluid channel
5, and pulsation absorber or bellows 7 is disposed in thus-branched
damping chamber F. Thus, the pulsation absorber of this embodiment
does not hamper the flow of the fluid, and therefore can avoid
pressure loss of the fluid.
[0052] Additionally, fluid coupling A3 of this embodiment has a
simple structure having a small size and a small number of
elements, as in the foregoing embodiments, and the fuel supply
system adopting fluid coupling A3 of this embodiment can be reduced
in weight and cost, and can be easily laid out in a limited space
in an engine room. Besides, the pulsation absorbers of FIGS.
2.about.7 are applicable to fluid coupling A3 of FIG. 8.
[0053] FIG. 9 is a sectional view showing a pulsation absorber
applicable to fluid coupling A3 of FIG. 8, according to still
another embodiment of the present invention. The pulsation absorber
of FIG. 9 includes a diaphragm 18 and an elastic member. Diaphragm
18 is formed by resin or rubber, and is positioned to partition
damping chamber F. The elastic member of this embodiment is
arranged to deform springily or elastically, or expand and
contract, in conjunction with deformation of diaphragm 18. The
elastic member of this embodiment is a coil spring 19 provided
between diaphragm 18 and support 11.
[0054] The fluid coupling adopting the pulsation absorber of this
embodiment can obtain similar effects and advantages as in the
foregoing embodiments. The pulsation absorber of FIG. 9 is
applicable to fluid coupling A2 of FIG. 2 of the elbow type. The
pulsation absorber of this embodiment may adopt each of the elastic
members of FIGS. 2.about.7 in place of coil spring 19 of FIG. 9.
Diaphragm 18 and the elastic member (molded member) may be formed
integrally from identical material by integral molding. Thereby,
the fluid coupling can have a structure with a small number of
elements, and can be reduced in cost.
[0055] According to another aspect of the present invention, the
fluid coupling includes: means (5) for passing fluid; and means (7;
7, 12; 7, 13; 7, 14; 7, 15, 16; 7, 17, 16; 18, 19) for absorbing
pulsation of the fluid by deforming in a same direction as the
fluid pulsates.
[0056] This application is based on a prior Japanese Patent
Application No. 2004-163141 filed on Jun. 1, 2004. The entire
contents of this Japanese Patent Application No. 2004-163141 are
hereby incorporated by reference.
[0057] Although the invention has been described above by reference
to certain embodiments of the invention, the invention is not
limited to the embodiments described above. Modifications and
variations of the embodiments described above will occur to those
skilled in the art in light of the above teachings. The scope of
the invention is defined with reference to the following
claims.
* * * * *