U.S. patent application number 11/899568 was filed with the patent office on 2008-03-13 for ejector and refrigerant cycle device with ejector.
This patent application is currently assigned to DENSO Corporation. Invention is credited to Mika Gocho, Hiroshi Oshitani, Yoshiaki Takano, Hirotsugu Takeuchi, Yasuhiro Yamamoto.
Application Number | 20080060378 11/899568 |
Document ID | / |
Family ID | 39154815 |
Filed Date | 2008-03-13 |
United States Patent
Application |
20080060378 |
Kind Code |
A1 |
Gocho; Mika ; et
al. |
March 13, 2008 |
Ejector and refrigerant cycle device with ejector
Abstract
An ejector for a refrigerant cycle device includes a nozzle
portion for decompressing and expanding refrigerant flowing
therein, and a body portion which accommodates the nozzle portion
to support the nozzle portion at a support portion. The body
portion has a refrigerant suction port from which refrigerant is
drawn by a high-speed refrigerant flow jetted from a nozzle outlet
of the nozzle portion. The nozzle portion is located in the body
portion to have an ejector refrigerant passage through which the
refrigerant flows. In the ejector, the nozzle portion is supported
in the body portion to have the following relationship of
0<L/d.ltoreq.14, in which L/d is a ratio of a length (L) between
a downstream tip portion of the support portion and the nozzle
outlet to a diameter (d) of the nozzle outlet.
Inventors: |
Gocho; Mika; (Obu-city,
JP) ; Takeuchi; Hirotsugu; (Nagoya-city, JP) ;
Takano; Yoshiaki; (Kosai-city, JP) ; Oshitani;
Hiroshi; (Toyota-city, JP) ; Yamamoto; Yasuhiro;
(Anjo-city, JP) |
Correspondence
Address: |
HARNESS, DICKEY & PIERCE, P.L.C.
P.O. BOX 828
BLOOMFIELD HILLS
MI
48303
US
|
Assignee: |
DENSO Corporation
Kariya-city
JP
|
Family ID: |
39154815 |
Appl. No.: |
11/899568 |
Filed: |
September 6, 2007 |
Current U.S.
Class: |
62/500 |
Current CPC
Class: |
F25B 2341/0013 20130101;
F25B 2500/01 20130101; F04F 5/46 20130101; F25B 41/00 20130101;
F04F 5/04 20130101; F25B 2341/0012 20130101 |
Class at
Publication: |
62/500 |
International
Class: |
F25B 1/06 20060101
F25B001/06 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 7, 2006 |
JP |
2006-242512 |
Claims
1. An ejector for a refrigerant cycle device, the ejector
comprising: a nozzle portion for decompressing and expanding
refrigerant flowing therein; and a body portion which accommodates
the nozzle portion to support the nozzle portion at a support
portion, the body portion having a refrigerant suction port from
which refrigerant is drawn by a high-speed refrigerant flow jetted
from a nozzle outlet of the nozzle portion, wherein: the nozzle
portion is located in the body portion to have an ejector
refrigerant passage through which the refrigerant jetted from the
nozzle outlet of the nozzle portion and the refrigerant drawn from
the refrigerant suction port flow; and the nozzle portion is
supported in the body portion to have the following relationship of
0<L/d.ltoreq.14, in which L/d is a ratio of a length (L) between
a downstream tip portion of the support portion and the nozzle
outlet to a diameter (d) of the nozzle outlet.
2. The ejector according to claim 1, wherein: the body portion has
a mixing portion in which the refrigerant jetted from the nozzle
outlet and the refrigerant drawn from the refrigerant suction port
are mixed; and the mixing portion has a wall thickness (t) and an
inner diameter (D), and a ratio (t/D) of the wall thickness (t) to
the inner diameter (D) is equal to or larger than 0.2.
3. The ejector according to claim 1, wherein: the nozzle portion
has a first part, a second part downstream from the first part in a
refrigerant flow of the nozzle portion and positioned to correspond
to an area of the refrigerant suction port, and a third part
downstream from the second part in the refrigerant flow of the
nozzle portion; and the first part of the nozzle portion is
supported by the body portion at the support portion.
4. The ejector according to claim 1, wherein: the nozzle portion
has a first part, a second part downstream from the first part in a
refrigerant flow of the nozzle portion and positioned to correspond
to an area of the refrigerant suction port, and a third part
downstream from the second part in the refrigerant flow of the
nozzle portion; and the third part of the nozzle portion is
supported by the body portion at the support portion.
5. The ejector according to claim 4, wherein: the nozzle portion
has a protrusion portion protruding from an outer wall surface of
the third part of the nozzle portion toward the body portion; and
the protrusion portion of the nozzle portion contacts an inner wall
of the body portion to form the support portion.
6. The ejector according to claim 4, wherein: the body portion has
a protrusion portion protruding from an inner wall of the body
portion to the nozzle portion at a position corresponding to the
third part of the nozzle portion; and the protrusion portion of the
body portion contacts an outer wall of the nozzle portion to form
the support portion.
7. The ejector according to claim 4, further comprising a support
member located between an inner wall of the body portion and an
outer wall of the third part of the nozzle portion; and the nozzle
portion is supported in the body portion by the support member.
8. The ejector according to claim 1, further comprising a driving
portion for driving the nozzle portion so as to move the nozzle
portion in an axial direction relative to the body portion, wherein
the nozzle portion is movable by the driving portion between a
first state where an outer wall of the nozzle portion is spaced
from an inner wall of the body portion such that the refrigerant
drawn from the refrigerant suction port flows, and a second state
where the outer wall of the nozzle portion contacts the inner wall
of the body portion to be supported by the body portion at the
support portion such that a refrigerant flow from the refrigerant
suction port is closed.
9. An ejector for a refrigerant cycle device, the ejector
comprising: a nozzle portion having therein a nozzle passage in
which high-pressure refrigerant before being decompressed flows,
the nozzle portion having an approximately cylindrical outer wall
portion and a nozzle outlet from which the refrigerant decompressed
in the nozzle passage is jetted; a body portion which accommodates
the nozzle portion to define a suction passage, between the nozzle
portion and the body portion, extending from the cylindrical outer
wall portion to the nozzle outlet, the body portion having a
refrigerant suction port that is opened radially outwardly of the
cylindrical outer wall portion to communicate with the suction
passage; a first fixing member for connecting and fixing the nozzle
portion to the body portion at a position upstream from the
refrigerant suction port in a refrigerant flow of the nozzle
passage; and a second fixing member for connecting and fixing the
nozzle portion to the body portion at a position downstream from
the refrigerant suction port in the refrigerant flow of the nozzle
passage.
10. The ejector according to claim 1, wherein: the nozzle portion
and the body portion are made of different members; and the nozzle
portion is fixed to the body portion by fastening or pressing means
to be supported by the body portion.
11. The ejector according to claim 1, wherein: the body portion has
a mixing portion in which the refrigerant jetted from the nozzle
outlet and the refrigerant drawn from the refrigerant suction port
are mixed; and the mixing portion has approximately a uniform wall
thickness (t) and a uniform inner diameter (D), and a ratio t/D of
the wall thickness (t) to the inner diameter (D) is equal to or
larger than 1.
12. The ejector according to claim 1, further comprising a cover
member, which is located to cover an outer surface of the body
portion at least in an area near the nozzle outlet, wherein the
cover member is made of a material to reduce at least one of
vibration and noise caused in the body portion.
13. The ejector according to claim 1, wherein: the body portion has
a mixing portion in which the refrigerant jetted from the nozzle
outlet and the refrigerant drawn from the refrigerant suction port
are mixed, and a diffuser in which a passage sectional area is
increased from the mixing portion toward downstream side; and the
body portion has a uniform outer wall surface at least in the
mixing portion and the diffuser.
14. The ejector according to claim 13, wherein: the mixing portion
has approximately a uniform wall thickness; and the diffuser has a
wall thickness that is gradually reduced from the mixing portion
toward downstream.
15. The ejector according to claim 13, wherein the body portion has
an approximately uniform cylindrical outer surface in an entire
area.
16. A refrigerant cycle device comprising: a compressor for sucking
and compressing refrigerant; a radiator for cooling high-pressure
refrigerant discharged from the compressor; the ejector according
to claim 1, the nozzle portion of the ejector being located to
decompress the refrigerant flowing from the radiator; a first
evaporator for evaporating the refrigerant flowing out of the
ejector; a branch passage branched from a refrigerant flow between
the radiator and the nozzle portion of the ejector, and joined to
the refrigerant suction port of the ejector; a throttle unit
located in the branch passage to decompress the refrigerant flowing
into the branch passage; a second evaporator located in the branch
passage downstream from the throttle unit; and a switching unit
located in the branch passage to switch a refrigerant flow to the
second evaporator.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application is based on Japanese Patent Application No.
2006-242512 filed on Sep. 7, 2006, the contents of which are
incorporated herein by reference in its entirety.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to an ejector and a
refrigerant cycle device having the ejector.
[0004] 2. Description of the Related Art
[0005] Refrigerant cycle devices having an ejector are described in
JP-A-2005-308380 (corresponding to U.S. Pat. No. 7,178,359) and
JP-A-2004-270460 (corresponding to US 2004/0172966 A1), for
example.
[0006] FIG. 18 shows an ejector 14 for a refrigerant cycle device
in a related art. The ejector 14 includes a nozzle portion 14a for
decompressing refrigerant from a radiator, a refrigerant suction
port 14d from which refrigerant is drawn by a high-speed
refrigerant flow jetted from a nozzle outlet of the nozzle portion
14a, a mixing portion 14b for mixing the refrigerant jetted from
the nozzle portion 14a and the refrigerant drawn from the
refrigerant suction port 14d, and a diffuser 14c. The nozzle
portion 14a is supported by a body portion 14e, and the refrigerant
suction port 14d is provided in the body portion 14e.
[0007] In a general operation of the refrigerant cycle device,
vapor refrigerant evaporated in an evaporator is drawn into the
ejector 14 through the refrigerant suction port 14d, and is mixed
with the driving refrigerant flow jetted from the nozzle portion
14a in the mixing portion 14b. However, if the refrigerant cycle
device is operated in a state where the ejector 14 is operated only
with the driving refrigerant flow jetted from the nozzle portion
14a without the suction refrigerant flow from the refrigerant
suction port 14d, the driving refrigerant flow jetted from the
nozzle portion 14a is turned to cause vortex flow at the nozzle
outlet side, thereby increasing the jet flow loss due to the vortex
flow shown by the arrows V. The vortex flow V is also caused when
the amount of the suction refrigerant flow drawn from the
refrigerant suction port 14d is small. When the jet flow loss due
to vortex flow V is increased, the outlet side of the nozzle
portion 14a and the body portion 14e near the nozzle outlet of the
nozzle portion 14a are vibrated, thereby increasing the refrigerant
passing noise. In addition, if the length L from a downstream tip
end of the nozzle support portion to the nozzle outlet is long in
the ejector 14, the vibration of the ejector 14 is more easily
caused.
[0008] Furthermore, when the ejector 14 is used for a refrigerant
cycle device having a first evaporator located downstream of the
ejector 14 and a second evaporator located in a branch passage
branched from a refrigerant passage at an upstream side of the
nozzle portion 14a and joined to the refrigerant suction port 14d,
the refrigerant passing noise generated in the ejector 14 is more
easily increased if the amount of the suction refrigerant flow from
the second evaporator to the refrigerant suction port 14d is small
or zero.
SUMMARY OF THE INVENTION
[0009] In view of the foregoing problems, it is an object of the
present invention to provide an ejector, which can reduce the loss
due to vortex flow at a nozzle outlet side so as to reduce
refrigerant passing noise.
[0010] It is another object of the present invention to provide a
refrigerant cycle device with an ejector, which can reduce
refrigerant passing noise.
[0011] According to an example of the present invention, an ejector
for a refrigerant cycle device includes a nozzle portion for
decompressing and expanding refrigerant flowing therein, and a body
portion which accommodates the nozzle portion to support the nozzle
portion at a support portion. The body portion has a refrigerant
suction port from which refrigerant is drawn by a high-speed
refrigerant flow jetted from a nozzle outlet of the nozzle portion.
The nozzle portion is located in the body portion to have an
ejector refrigerant passage through which the refrigerant jetted
from the nozzle outlet of the nozzle portion and the refrigerant
drawn from the refrigerant suction port flow. In addition, the
nozzle portion is supported in the body portion to have the
following relationship of 0<L/d.ltoreq.14, in which L/d is a
ratio of a length (L) between a downstream tip portion of the
support portion and the nozzle outlet to a diameter (d) of the
nozzle outlet. Accordingly, a distance between the tip end (nozzle
outlet) of the nozzle portion and the support portion where the
nozzle portion is supported by the body portion can be shortened,
thereby reducing vibration of the nozzle portion and the body
portion.
[0012] The body portion has a mixing portion in which the
refrigerant jetted from the nozzle outlet and the refrigerant drawn
from the refrigerant suction port are mixed. For example, the
mixing portion may have a wall thickness (t) and an inner diameter
(D), and a ratio t/D of the wall thickness (t) to the inner
diameter (D) may be equal to or larger than 0.2. In this case, the
vibration of the ejector can be further reduced.
[0013] For example, the nozzle portion may have a first part, a
second part downstream from the first part in a refrigerant flow of
the nozzle portion and positioned to correspond to an area of the
refrigerant suction port, and a third part downstream from the
second part in the refrigerant flow of the nozzle portion. In this
case, the first part of the nozzle portion may be supported by the
body portion at the support portion.
[0014] Alternatively, the third part of the nozzle portion may be
supported by the body portion at the support portion. In this case,
the nozzle portion may have a protrusion portion protruding from an
outer wall surface of the third part of the nozzle portion toward
the body portion, and the protrusion portion of the nozzle portion
may contact an inner wall of the body portion to form the support
portion. Alternatively, the body portion may have a protrusion
portion protruding from an inner wall of the body portion to the
nozzle portion at a position corresponding to the third part of the
nozzle portion, and the protrusion portion of the body portion may
contact an outer wall of the nozzle portion to form the support
portion.
[0015] Alternatively, a support member may be located between an
inner wall of the body portion and an outer wall of the third part
of the nozzle portion. In this case, the nozzle portion may be
supported in the body portion by the support member.
[0016] Furthermore, the nozzle portion may be movable by a driving
portion between a first state where an outer wall of the nozzle
portion is spaced from an inner wall of the body portion such that
the refrigerant drawn from the refrigerant suction port flows, and
a second state where the outer wall of the nozzle portion contacts
the inner wall of the body portion to be supported by the body
portion at the support portion such that a refrigerant flow from
the refrigerant suction port is closed.
[0017] According to another example of the present invention, an
ejector for a refrigerant cycle device includes a nozzle portion
having therein a nozzle passage in which high-pressure refrigerant
before being decompressed flows, and a body portion which
accommodates the nozzle portion. The nozzle portion has an
approximately cylindrical outer wall portion and a nozzle outlet
from which the refrigerant decompressed in the nozzle passage is
jetted, and a suction passage is provided between the nozzle
portion and the body portion to extend from the cylindrical outer
wall portion of the nozzle portion to the nozzle outlet. The body
portion has a refrigerant suction port that is opened radially
outwardly of the cylindrical outer wall portion to communicate with
the suction passage. In addition, the ejector further includes a
first fixing member for connecting and fixing the nozzle portion to
the body portion at a position upstream from the refrigerant
suction port in a refrigerant flow of the nozzle passage, and a
second fixing member for connecting and fixing the nozzle portion
to the body portion at a position downstream from the refrigerant
suction port in the refrigerant flow of the nozzle passage.
Therefore, the distance between the tip end (nozzle outlet) of the
nozzle portion to the second fixing member as the support portion
can be shortened, thereby reducing vibration of the nozzle portion.
Thus, the refrigerant passing noise can be effectively reduced even
when the vortex flow is caused at the side of the nozzle outlet in
a case where the ejector is operated with a refrigerant driving
flow in the nozzle portion without a refrigerant suction flow from
the refrigerant suction port or a very small refrigerant suction
flow.
[0018] A mixing portion of the ejector may have approximately a
uniform wall thickness (t) and a uniform inner diameter (D), and a
ratio t/D of the wall thickness (t) to the inner diameter (D) may
be equal to or larger than 1. In this case, vibration of the body
portion around the nozzle outlet can be further reduced.
[0019] The ejector can be suitably used for a refrigerant cycle
device in which high-pressure refrigerant is decompressed at the
nozzle portion of the ejector.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] Additional objects and advantages of the present invention
will be more readily apparent from the following detailed
description of preferred embodiments when taken together with the
accompanying drawings. In which:
[0021] FIG. 1 is a schematic diagram showing an example of a
refrigerant cycle device according to embodiments of the present
invention;
[0022] FIG. 2A is a sectional view showing a part of an ejector
according to a first embodiment of the present invention, and FIG.
2B is an enlarged sectional view showing the part IIB in FIG.
2A;
[0023] FIG. 3 is a sectional view showing a fixing method of a
nozzle portion and a body portion in the ejector according to the
first embodiment;
[0024] FIG. 4 is a graph showing the relationship between a noise
level difference and a ratio L/d of a distance L between a
downstream tip portion of the nozzle support portion and a nozzle
outlet to a nozzle outlet diameter d, according to the first
embodiment;
[0025] FIG. 5 is a graph showing the relationship between the noise
level difference and a ratio t/D of a body wall thickness t to an
inner diameter D of the mixing portion, according to the first
embodiment;
[0026] FIG. 6 is a sectional view showing a part of an ejector
according to a first example of a second embodiment of the present
invention;
[0027] FIG. 7 is a cross-sectional view taken along the line
VII-VII in FIG. 6;
[0028] FIG. 8 is a sectional view showing a part of an ejector
according to a second example of the second embodiment of the
present invention;
[0029] FIG. 9 is a cross-sectional view taken along the line IX-IX
in FIG. 8;
[0030] FIG. 10 is a sectional view showing a part of an ejector
according to a third example of the second embodiment of the
present invention;
[0031] FIG. 11 is a cross-sectional view taken along the line XI-XI
in FIG. 10;
[0032] FIG. 12 is a sectional view showing an ejector according to
a third embodiment of the present invention;
[0033] FIG. 13 is an enlarged sectional view showing a part XIII of
the ejector in FIG. 12 when the ejector has therein a refrigerant
suction flow;
[0034] FIG. 14 is an enlarged sectional view showing the part XIII
of the ejector in FIG. 12 when the ejector has no refrigerant
suction flow;
[0035] FIG. 15 is a sectional view showing a part of an ejector
according to a fourth embodiment of the present invention;
[0036] FIG. 16 is a cross-sectional view taken along the line
XVI-XVI in FIG. 15;
[0037] FIG. 17 is a sectional view showing a part of an ejector
according to another embodiment of the present invention; and
[0038] FIG. 18 is a sectional view showing a part of an ejector in
a related art.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
First Embodiment
[0039] FIG. 1 is a schematic diagram showing an example of a
refrigerant cycle device with an ejector 1 of a first embodiment.
The operation of the refrigerant cycle device with the ejector 1
may be similar to that of U.S. Pat. No. 7,178,359, which are
incorporated by reference.
[0040] As shown in FIG. 1, the refrigerant cycle device includes a
compressor 12 for drawing and compressing refrigerant, a radiator
13 for cooling high pressure refrigerant discharged from the
compressor 12, a refrigerant circulation path 11 for introducing
the refrigerant flowing out of the radiator 13 into a nozzle
portion 2 of the ejector 1, a first evaporator 15 for evaporating
the refrigerant flowing out of the ejector 1, and a branch passage
16 branched from the refrigerant circulation path 11 at a position
upstream from the nozzle portion 2 and downstream from the radiator
13. A downstream end of the branch passage 16 is coupled to a
refrigerant suction port 3a of the ejector 1. An electromagnetic
valve 20 is located in the branch passage 16 to interrupt a
refrigerant flow to the second evaporator 18, and a flow adjusting
valve 17 is located to decompress refrigerant flowing into the
second evaporator 18 and to adjust a flow amount of the refrigerant
flowing into the second evaporator 18. The electromagnetic valve 20
and the flow adjusting valve 17 may be integrated as one unit.
[0041] In the example of FIG. 1, the refrigerant outlet of the
first evaporator 15 can be directly coupled to a refrigerant
suction side of the compressor 12. However, a vapor-liquid
separator may be located between the first evaporator 15 and the
refrigerant suction side of the compressor 12. The first evaporator
15 may be singly operated when the refrigerant flow to the second
evaporator 18 is shut by the electromagnetic valve 20, or both the
first evaporator 15 and the second evaporator 18 may be
simultaneously operated. The operation of the refrigerant cycle
device with the ejector 1 is generally known, and the detail
explanation thereof is omitted. In this embodiment, the first
evaporator 15 and the second evaporator 18 may be located to cool a
single compartment to be cooled or may be located to cool different
compartments to be cooled.
[0042] Next, the structure of the ejector 1 will be described.
[0043] As shown in FIG. 2A, the ejector 1 of this embodiment
includes the nozzle portion 2 and a body portion 3 which is
disposed to support the nozzle portion 2. The nozzle portion 2 has
therein a nozzle passage 2a for decompressing and expanding
high-pressure refrigerant from the radiator 13. The nozzle portion
2 is adapted to isentropically decompress and expand high-pressure
refrigerant by decreasing the passage sectional area of the nozzle
passage 2a to a small level, and by ejecting high-speed refrigerant
from a nozzle outlet (nozzle tip) 2b. The refrigerant at the nozzle
outlet 2b is decompressed partially so called as a middle-pressure
refrigerant that is close to and could be categorized as a
low-pressure refrigerant. The nozzle portion 2 may be referred to
as a functional member that ejects the high-pressure refrigerant
into a low-pressure region in the refrigerant cycle.
[0044] The body portion 3 has a cylindrical shape on its outer wall
surface. The nozzle portion 2 is disposed inside the body portion
3. The body portion 3 has the refrigerant suction port 3a located
in the same space as the nozzle outlet 2b of the nozzle portion 2,
for sucking the vapor-phase refrigerant from the second evaporator
18 thereinto by the high-velocity refrigerant flow ejected from the
nozzle outlet 2b of the nozzle portion 2. The body portion 3
constitutes ejector flow passages for the sucked flow of the
refrigerant from the refrigerant suction port 3a, and the
refrigerant driving flow jetted from the nozzle outlet 2b. That is,
the body portion 3 includes a suction path portion 3b serving as a
flow path of the sucked flow of the refrigerant from the
refrigerant suction port 3a, and a mixing portion 3c and a diffuser
3d which serve as a flow path for the mixed flow into which the
sucked refrigerant flow from the refrigerant suction port 3a and
the driving refrigerant flow ejected from the nozzle portion 2 are
mixed. The diffuser 3d is formed in such a shape to gradually
increase the passage area of the refrigerant, and is provided to
decelerate the refrigerant flow and to increase the refrigerant
pressure, that is, to convert the velocity energy of the
refrigerant into the pressure energy.
[0045] The nozzle portion 2 and the body portion 3 are constructed
of different components, that is, individual structures. The nozzle
portion 2 is made of metal, such as, stainless or brass, and the
body portion 3 is made of metal, such as aluminum, for example.
[0046] FIG. 2B is an enlarged view of the area enclosed by the
broken line IIB shown in FIG. 2A. The ejector 1 of this embodiment
has such a structure that the nozzle portion 2 is supported by the
body portion 3 near the nozzle outlet 2b, as compared to that in a
conventional ejector.
[0047] As shown in FIG. 2B, the nozzle portion 2 has an elongated
shape extending linearly, and has such a contour that the outer
diameter of a first part 2d (nozzle support portion) on the
upstream side of the driving flow is larger than that of a second
part 2c (nozzle un-support portion) opposed to the refrigerant
suction port 3a. That is, the second part 2c is the part
corresponding to the refrigerant suction port 3a in a refrigerant
flow of the nozzle portion 2. The nozzle portion 2 has an outer
wall of the first part 2d on the upstream side of the refrigerant
driving flow, such that the first part 2d is in contact with the
inner wall of the body portion 3, and the part on the nozzle outlet
2b side from the first part 2d is not in contact with the body
portion 3. That is, in the nozzle portion 2, the first part 2d on
the driving flow upstream side is supported by the body portion 3,
rather than the second part 2c that is opposed to the refrigerant
suction port 3a. In this embodiment, the position of a downstream
tip portion 2e of the nozzle support portion (first part 2d) of the
nozzle portion 2, supported by the body portion 3, is approximately
identical to that of an end of the refrigerant suction port 3a. It
is noted that these positions may not necessarily be identical to
each other.
[0048] Regarding the dimension of the nozzle portion 2, a length L
from the downstream tip portion 2e of the first part 2d to the
nozzle outlet 2b is set such that the ratio L/d of the length L to
the nozzle outlet diameter d is 14 or less.
[0049] The tip portion 2e of the first part 2d is a nozzle outlet
side end located within the range of the nozzle portion 2 supported
by the body portion 3. The length L means a linear distance in the
extending direction of the nozzle portion 2, in other words, in the
axial direction of the nozzle portion 2, or in the flow direction
of the driving flow of the refrigerant. The nozzle outlet diameter
d means the inner diameter of the nozzle at the nozzle outlet 2b.
The sectional shape of the flow path at the nozzle outlet 2b is not
limited to a circular. When the sectional shape of the flow path at
the nozzle outlet 2b is not circular, the nozzle outlet diameter
may be the maximum dimension of a nozzle aperture at the nozzle
outlet 2b.
[0050] For example, L/d=1. That is, the length L may be the same as
the nozzle outlet diameter d. The lower limit of the L/d is the
minimum value that can be implemented and which has only to be
larger than zero.
[0051] In the ejector 1 of this embodiment, a part of the body
portion 3 near the nozzle outlet 2b, that is, the mixing portion 3c
has a thickness larger than that the other part, as shown in FIG.
2A, as will be described later.
[0052] As shown in FIG. 2B, the body portion 3 is constructed of a
single component, in which a suction portion 3b and a mixing
portion 3c are integrally formed. The body portion 3 has a
cylindrical outer shape without any stepped portions on the outer
wall in the axial direction. The suction portion 3b of the body
portion 3 has a different inner diameter than that of the mixing
portion 3c thereof. That is, the thickness of the suction portion
3b is different from that of the mixing portion 3c, so as to set
the refrigerant flow path sections of the suction portion 3b and
the mixing portion 3c to desired sizes.
[0053] The mixing portion 3c is an area where the refrigerant
driving flow and the refrigerant suction flow are mixed. The mixing
portion 3c is disposed on the downstream side of the refrigerant
flow from the nozzle outlet 2b in the body portion 3, with the
sectional area of the refrigerant flow path being constant. In this
embodiment, all the area of the mixing portion 3c has the constant
thickness in the body portion 3.
[0054] The size of the body portion 3 is set to satisfy the
following relationship that the ratio t/D of the body thickness t
to the inner diameter D of the body portion 3 at the mixing portion
3c is 1.0 or more. Here, the body thickness t is the wall thickness
of the body portion 3 at the mixing portion 3c.
[0055] In this embodiment, the position of the nozzle outlet 2b is
identical to that of the inlet of the mixing portion 3. Although
theses positions are not identical to each other, the body
thickness t on the downstream side of the refrigerant flow of the
body portion 3 away from the nozzle outlet 2b may be more
preferable when the t/D is 1.0 or more.
[0056] Now, a method of manufacturing the ejector 1 with the
above-described structure will be described below. FIG. 3 is a
sectional view for explaining a method for fixing the nozzle
portion 2 to the body portion 3.
[0057] The nozzle portion 2 and the body portion 3 are respectively
manufactured, for example, by die-casting of metal parts, and then
by cutting the parts, for example, by drilling. The nozzle portion
2 is inserted into the body portion 3 as indicated by the arrow
shown by a solid line in FIG. 3, so that the nozzle portion 2 is
pressed and fixed into the body portion 3. Alternatively, the
nozzle portion 2 is caulked and fastened to the body portion 3 as
indicated by the arrow shown by a broken line in FIG. 3. This can
manufacture the ejector 1 with the above-described structure.
[0058] Now, the ejector 1 in this embodiment will be described
below in detail.
[0059] (1) As mentioned above, in this embodiment, the position of
a part of the nozzle portion 2 supported by the body portion 3b,
that is, the nozzle support position can be located near the nozzle
outlet 2b, thereby reducing the vibration of the nozzle portion 2
at a position near the nozzle outlet 2b where the refrigerant flow
velocity is fastest.
[0060] Accordingly, it is possible to restrain an increase in noise
occurring when the refrigerant passes in a case where the
refrigerant cycle device is in an operational state only of the
refrigerant driving flow without the refrigerant suction flow, or
in a case where the refrigerant cycle device is in an operational
state of an extremely little refrigerant suction flow with respect
to the refrigerant driving flow.
[0061] FIG. 4 shows a relationship between a difference in noise
level of the ejector between the presence and absence of the
refrigerant suction flow, and the ratio L/d of the length L to the
nozzle outlet diameter d. Here, the length L is a length from the
tip portion 2e of the first part 2d to the nozzle outlet 2b in the
axial direction. FIG. 4 shows the result of measurement obtained
when the ratio t/D of the body thickness t to the inner diameter D
of the mixing portion is 0.2 in the ejector 1 shown in FIG. 2B. The
difference in noise level (noise level difference) represented in
the longitudinal axis of FIG. 4 is obtained by performing frequency
correction.
[0062] As shown in FIG. 4, as the L/d is decreased from about 20 to
about 5, the difference in noise level tends to decrease. When the
L/d is smaller than about 5, the difference in noise level further
decreases. When the L/d is zero, it is estimated that the
difference in noise level is closest to zero.
[0063] It is generally known that the lower limit of a sound
pressure level recognized by human being is 3 dB. When the
difference in noise level is equal to or less than 3 dB, the
difference in sound between the presence and absence of the
refrigerant suction flow hardly exists.
[0064] FIG. 4 shows that when the L/d is 14, the difference in
noise level is about 3 dB. Thus, as can be seen from the above,
when the L/d is greater than zero and not more than 14
(0<L/d.ltoreq.14), it is possible to decrease the noise of the
passing refrigerant occurring due to transmission of vibration.
[0065] As the t/D becomes greater than 0.2, the result of
measurement shifts toward the decrease in noise level difference.
When the t/D is equal to or greater than 0.2, the difference in
noise level becomes 3 dB or less in a case where
0<L/d.ltoreq.14.
[0066] The sound pressure level of 1 dB or less is a level that the
human being can hardly recognize. As shown in FIG. 4, the
difference in noise level becomes about 1 dB when the L/d is 9.
Therefore, the L/d may be more preferable 9 or less
(L/d.ltoreq.9).
[0067] (2) This embodiment can restrain the vibration of the nozzle
portion 2 near the nozzle outlet 2b, thus lessening an amount of
displacement of the nozzle outlet 2b of the nozzle portion 2 in
operation of the refrigerant cycle device. This can reduce the
influence of the repeated stress onto the nozzle material so as to
improve the durability of the nozzle portion 2.
[0068] (3) In this embodiment, the nozzle support position is
located at the first part 2d on the upstream side of the
refrigerant driving flow away from the second part 2c opposed to
the refrigerant suction port 3a of the nozzle portion 2. Thus, the
nozzle support position is located closer to the nozzle outlet 2b,
and the refrigerant suction port 3a is located in the vicinity of
the nozzle outlet 2b.
[0069] Accordingly, it is possible to reduce a refrigerant flow
path passing through the surrounding part of the nozzle portion 2
with the small sectional area, that is, a flow path of the
refrigerant suction flow from the refrigerant suction port 3a to
the mixing portion 3c, thereby decreasing loss in pressure of the
refrigerant suction flow, and leading to a reduction in pressure
loss of the refrigerant inside the ejector. As a result, the amount
of increase in the refrigerant pressure of the ejector can be
large, thereby enhancing the ejector effect in the refrigerant
cycle device.
[0070] (4) In the ejector 1 of this embodiment, the ratio t/D of
the body thickness t of the mixing portion 3c to the inner diameter
D of the mixing portion 3c is 1.0 or more. Thus, the part near the
nozzle outlet 2b of the body portion 3 is relatively thick.
[0071] This can restrain the vibration of the body portion 3
occurring due to an excessive loss of vortex near the nozzle outlet
2b, thereby further decreasing the noise of the passing
refrigerant.
[0072] FIG. 5 shows a relationship between a difference in noise
level (noise level difference) of the ejector between the presence
and absence of the refrigerant suction flow, and the ratio t/D of
the body thickness t to the diameter D of the mixing portion 3.
FIG. 5 shows the result of measurement in a case where the L/d is
14.
[0073] As shown in FIG. 4, when the L/d is 14 and t/D is 0.2, the
difference in noise level is about 3 dB. FIG. 5 shows that as the
t/D becomes larger than 0.2, the difference in noise level becomes
smaller. Setting the t/D to 1 or more can set the difference in
noise level to 1 dB or less.
[0074] Setting the t/D to 1 or more means that the thickness t is
equal to or larger than the inner diameter D. The upper limit of
the t/D is determined by constraints of mounting places of the
ejector, and can be arbitrarily set within an allowable range.
[0075] Thus, a margin for external corrosion due to an influence
from an external environment and for internal corrosion due to an
influence from an internal flowing material is increased, thereby
enabling the improvement in durability in the ejector 1.
[0076] In this embodiment, the thickness of the mixing portion 3c
is increased, so that the body portion 3 can be constructed of a
single component. This is because thickening the mixing portion 3c
can uniformize the outer diameter of the body portion 3 from the
suction portion 3b to the mixing portion 3c, thereby making the
contour of the body portion 3 in a simple shape without stepped
portions on the external wall in the axial direction.
[0077] Since the contour (outer wall surface) of the body portion 3
is formed in a simple shape in this embodiment, attachment to the
outer periphery of the ejector 1 can be performed easily by packing
or the like.
Second Embodiment
[0078] A second embodiment of the present invention will be now
described with reference to FIGS. 6 to 11. In an ejector 1 of the
second embodiment, a part of the nozzle portion 2 downstream from
the second part 2c in a refrigerant driving flow is also supported.
FIGS. 6 and 7 show a first example of the second embodiment.
[0079] In the ejector 1 shown in FIG. 6, a third part 2f positioned
on the downstream side of the driving flow of the nozzle portion 2
than the second part 2c opposed to the refrigerant suction port 3a
is provided with protrusions 2g. The protrusions 2g are disposed on
the outer wall of the third part 2f of the nozzle portion 2 and
protrude radially outside toward the inner wall of the body portion
3. The protrusions 2g are located to abut against the inner wall of
the body portion 3, and thus the nozzle portion 2 is also supported
by the body portion 3 at the third part 2f.
[0080] The third part 2f on the downstream side of the driving flow
of the nozzle portion 2 away from the second part 2c opposed to the
refrigerant suction port 3a is, in other words, a part located
between the refrigerant suction port 3a in the axial direction of
the nozzle portion 2 (in the longitudinal direction of the nozzle
portion 2) and the nozzle outlet 2b.
[0081] The protrusions 2g are disposed partly, and not over the
entire circumferential area of the third part 2f of the nozzle
portion 2, so as not to cover the flow path of the refrigerant
suction flow in the circumferential direction of the nozzle portion
2 when viewing the section of the nozzle portion 2 with respect to
the refrigerant flow in the nozzle portion 2. For example, as shown
in FIG. 7, four protrusions 2g are disposed at equal intervals in
the outer circumferential direction of the nozzle portion 2 at the
third part 2f. In this example, the third part 2f of the nozzle
portion 2 is fixed to the body portion 3 at four points. However,
the third part 2f of the nozzle portion 2 may be fixed to the body
portion 3 at plural point other than four.
[0082] The nozzle portion 2 of this embodiment has a thick base 21,
and a cylindrical part 22 which has a thickness thinner than the
base 21. The cylindrical part 22 extends from the base 21 in the
axial direction. The cylindrical part 22 defines therein a
high-pressure refrigerant flow path 2a. The part 22 further defines
an outlet 2b of the high-pressure refrigerant flow path 2a at its
tip end. The cylindrical part 22 includes an axis portion 23 having
a substantially constant outer diameter, and a conical portion 24
having an outer diameter gradually decreased in size from the axis
portion 23 toward the outlet 2b. The nozzle portion 2 is disposed
in the cylindrical body portion 3. A low-pressure refrigerant flow
path 25 enclosing the cylindrical part 22 is formed to be defined
between the nozzle portion 2 and the body portion 3. The nozzle
portion 2 has both ends in the axial direction via the suction
portion 3a connected and fixed to the body portion 3. The nozzle
portion 2 and the body portion 3 are connected and fixed to each
other by the base 21 on the upstream side of the refrigerant flow
in the nozzle portion 2 from the refrigerant suction port 3a.
Furthermore, the nozzle portion 2 and the body portion 3 are
connected and fixed to each other by the protrusions 2g (support
members) on the downstream side of the refrigerant flow in the
nozzle portion 2 from the refrigerant suction port 3a. The
protrusion 2g as the support member may be a stick-like or
plate-like member extending in the radial direction. The nozzle
portion 2 is supported and fixed by the plural protrusions 2g
disposed to be distributed at equal intervals in the
circumferential direction. The protrusion 2g as the support member
is provided at a position away from the base 21 in the axial
direction of the nozzle portion 2. Each of the protrusions 2g as
the support members is provided near the boundary between the axis
portion 23 and the conical portion 24. As a result, the nozzle
portion 2 protrudes from the protrusions 2g as the support members
toward downstream. The protrusions 2g as the support members
support the part located slightly closer to the tip end rather than
the center in the entire length of the cylindrical part 22.
[0083] At this time, the end on the nozzle outlet 2b side of the
protrusion 2g is a tip portion 2e of the support portion of the
nozzle portion 2. A length L from the tip portion 2e of the support
portion to the nozzle outlet 2b is set such that the ratio L/d of
the length L to a nozzle outlet diameter d is 14 or less.
[0084] Therefore, also in this embodiment, the nozzle support
position can be located near the nozzle outlet 2b, thereby
restraining the vibration of the nozzle portion 2 near the nozzle
outlet 2b where the refrigerant flow velocity is fastest, like the
first embodiment.
[0085] It is noted that the number of the protrusions 2g is not
limited to four, but may be any number that is more than one and
which can be arbitrarily changed as long as the nozzle portion 2 is
fixed to the body portion 3. Also, the shape of the protrusions 2g
can be arbitrarily changed.
[0086] Now, modified examples of the embodiments will be described
below in detail.
[0087] FIG. 8 is a sectional view of the ejector 1 in a second
example of the second embodiment, and FIG. 9 is a sectional view
taken along a line IX-IX of FIG. 8. In the first example, the
protrusions 2g are provided in the nozzle portion 2, however, in
the second example, protrusions 3e may be provided not in the
nozzle portion 2, but in the body portion 3 as shown in FIGS. 8 and
9. That is, protrusions 3e which protrude radially inside toward
the nozzle portion 2 are provided on the inner wall on the
downstream side of the refrigerant flow of the body portion 3 away
from the refrigerant suction port 3a in the structure of the
ejector 1. The protrusions 3e may be brought into contact with the
outer wall of the nozzle portion 2, thereby supporting the nozzle
portion 2 by the body portion 3.
[0088] It is noted that although in the first and second examples
the protrusions are provided only in one of the nozzle portion 2
and the body portion 3, the protrusions 2g and 3e may be provided
in both of the nozzle portion 2 and the body portion 3.
[0089] FIG. 10 is a sectional view of an ejector 1 in a third
example of the second embodiment, and FIG. 11 is a sectional view
taken along the line XI-XI of FIG. 10. Although in the first and
second examples, the fixing part (support part) between the nozzle
portion 2 and the body portion 3 is provided in either the nozzle
portion 2 or the body portion 3, a fixing part may be constructed
of a component different from the nozzle portion 2 and the body
portion 3 as shown in FIGS. 10 and 11.
[0090] That is, in the ejector 1 shown in FIGS. 10 and 11, a
retaining ring 4 is disposed between the inner peripheral surface
of the body portion 3 and the outer peripheral surface of the
nozzle portion 2, at a position downstream from the second part 2c
of the nozzle portion 2. The retaining ring 4 has such a shape as
not to cover the flow path of the refrigerant suction flow. For
example, the retaining ring 4 includes a plurality of fixing
portions 4a for fixing the nozzle portion 2 to the body portion 3,
and connection portions 4b for connecting the adjacent fixing
portions 4a and forming a flow path between the nozzle portion 2
and the connection portion itself. The retaining ring 4 is made of,
for example, organic material, such as resin or rubber, or the same
metal material as that of the nozzle portion 2 or the body portion
3.
[0091] At this time, the fixing portions 4a, like the protrusions
2g and 3e as explained in the first and second examples, are partly
disposed in the circumferential direction of the nozzle portion.
The shape of the retaining ring 4 is not limited to the shape shown
in FIGS. 10 and 11, and may be any shape that is changed so as to
fix the nozzle portion 2 to the body portion 3 not to cover all the
flow path of the refrigerant suction flow.
Third Embodiment
[0092] In a third embodiment, the part on the upstream side of the
refrigerant driving flow in the nozzle portion 2 from the second
part 2c opposed to the refrigerant suction port 3a is supported by
the body portion 3. In addition, the part on the downstream side of
the refrigerant driving flow in the nozzle portion 2 from the
second part 2c is also located to be supported by the body portion
3.
[0093] As shown in FIG. 12, the ejector 1 of this embodiment
includes a driving portion 5 for driving the nozzle portion 2 in
the axial direction as indicated by the arrow in the figure to
allow the nozzle portion 2 to be displaced with respect to the body
portion 3. The driving portion 5 is controlled by control means
(not shown).
[0094] As the driving portion 5 can be employed, for example, a
stepping motor, a floating structure using a fluid force, a
mechanical driving means, such as a check valve structure or the
like, or an electric driving means, such as a proportional solenoid
or the like.
[0095] The shapes of the nozzle portion 2 and the body portion 3 of
this embodiment are basically the same as those in the first and
second embodiments. The outer diameter of the nozzle portion 2 is
larger than the inner diameter of the mixing portion 3c of the body
portion 3. When the nozzle portion 2 is moved to the mixing portion
3c, the outer wall of the nozzle portion 2 is in contact with the
inner wall of the body portion 3.
[0096] More specifically, the outer shape of the tip side portion
of the nozzle portion 2 is formed in a tapered shape to form a
tapered part 2h such that the outer diameter of the tapered part 2h
of the nozzle portion 2 is gradually decreased in size toward the
nozzle outlet 2b. The inside shape of the body portion 3 is formed
in such a tapered shape that the inner diameter of the suction
portion 3b is gradually decreased in size toward the mixing portion
3c. When the nozzle portion 2 is inserted into the mixing portion
3c, the tapered part 2h of the nozzle portion 2 is brought into
contact with the inner wall constituting the suction portion
3b.
[0097] In this embodiment, the driving portion 5 can be controlled
by the control means to displace the position of the nozzle portion
2 as shown in FIGS. 13 and 14.
[0098] As shown in FIG. 13, the refrigerant cycle device in an
operational condition in presence of the refrigerant suction flow
inside the ejector 1 is in a first state where the outer wall of
the tapered part 2h of the nozzle portion 2 is spaced apart from
the inner wall of the suction portion 3b of the body portion 3 to
form the flow path of the refrigerant sucked from the refrigerant
suction port 3a.
[0099] As shown in FIG. 14, the refrigerant cycle device in an
operational condition in the absence of the refrigerant suction
flow inside the ejector 1 is in a second state where the nozzle
portion 2 is displaced from the state shown in FIG. 13 so as to
stick into the mixing portion 3b, thereby causing the nozzle
portion 2 to be abutted against the body portion 3. In the second
state, the tapered part 2h of the nozzle portion 2 is brought into
contact with the inner wall of the body portion 3 constituting the
suction portion 3b thereby to close the flow path of the
refrigerant sucked from the refrigerant suction port 3a.
[0100] At this time, the area where the tapered part 2h of the
nozzle portion 2 is in contact with the suction portion 3b of the
body portion 3 is also used as the nozzle support position. The
ratio L/d of the length L from the tip portion 2e of the support
portion to the nozzle outlet 2b to the diameter d of the nozzle
outlet is 14 or less.
[0101] In the third embodiment, in the absence of the refrigerant
suction flow inside the ejector 1, the nozzle portion 2 is abutted
against the body portion 3, thereby the tapered part 2h of the
nozzle portion 2 is supported by the suction portion 3b of the body
portion 3.
[0102] Thus, also in the third embodiment, the nozzle support
position can be located near the nozzle outlet 2b, thereby
preventing the vibration of the nozzle portion 2 near the nozzle
outlet 2b where the refrigerant flow velocity is fastest, like the
first and second embodiments.
[0103] In the third embodiment, the nozzle portion 2 is abutted
against the body portion 3 in the absence of the refrigerant
suction flow inside the ejector 1 to close the flow path of the
refrigerant sucked from the refrigerant suction port 3a.
Accordingly, it is possible to restrain the occurrence of the
vortex of the driving flow, even when refrigerant is not drawn from
the second evaporator 18 to the refrigerant suction port 3a
[0104] Therefore, the effect of restraining the refrigerant passing
noise occurring due to the increased loss in vortex at the nozzle
outlet 2b can be more improved.
[0105] Since the nozzle portion 2 is abutted against the body
portion 3 so as to close the flow path of the refrigerant sucked
from the refrigerant suction port 3a in the ejector 1 of this
embodiment, the ejector 1 can also be used as an electromagnetic
valve for intermittently allowing the refrigerant suction flow to
pass through. In this case, for example, the electromagnetic valve
20 can be omitted from the refrigerant cycle device shown in FIG.
1.
Fourth Embodiment
[0106] A fourth embodiment of the present invention will described
with reference to FIGS. 15 and 16. As shown in FIGS. 15 and 16, an
ejector 1 of this embodiment is provided with an anti-vibration
member 6 (vibration prevention member, cover member) for preventing
the vibration of the body portion 3 with respect to the ejector 1
shown in FIG. 2A.
[0107] The anti-vibration member 6 is located to prevent the
vibration from being transmitted to the outside, or to lessen the
vibration. The anti-vibration member 6 is constructed of an elastic
body which is made of rubber or the like, typified by butyl rubber,
for example. The anti-vibration member 6 is disposed to cover the
entire outer periphery of the body portion 3. This can restrain the
vibration of the body portion 3 near the nozzle outlet 2b due to
the increase in loss of the vertex.
[0108] The anti-vibration member 6 may not necessarily cover the
entire area of the outer periphery of the body portion 3, and has
only to cover the downstream side part of the refrigerant flow from
the nozzle outlet 2b, located near the nozzle outlet 2b on the
outer periphery of the body portion 3.
[0109] Instead of the anti-vibration member 6, a soundproof member
made of porous material or the like may be provided on the outer
periphery of the body portion 3.
Other Embodiments
[0110] Although the present invention has been fully described in
connection with the preferred embodiments thereof with reference to
the accompanying drawings, it is to be noted that various changes
and modifications will become apparent to those skilled in the
art.
[0111] For example, the above first embodiment has explained the
example in which the nozzle portion 2 and the body portion 3 of the
ejector 1 are individual structures, but the nozzle portion 2 and
the body portion 3 may be an integrated structure constructed of
one component, as shown in FIG. 17. The structures of other
components of the ejector 1 are the same as those of the first
embodiment.
[0112] The ejector 1 shown in FIG. 17 may be made of, for example,
aluminum, and manufactured using a mold.
[0113] Also in the ejector 1 shown in FIGS. 6 to 11 as described in
the second embodiment, the nozzle portion 2 and the body portion 3
can be constructed of an integrated structure as mentioned above.
The integrated structure of the nozzle portion 2 and the body
portion 3 can securely fix the nozzle portion 2 to the body portion
3, as compared to the individual structures of the nozzle portion 2
and the body portion 3, thereby further restraining the vibration
of the nozzle portion 2.
[0114] The above-described embodiments have described the example
which satisfies the following both conditions: 0<L/d.ltoreq.14,
and t/D.gtoreq.1. Even if the condition of t/D.gtoreq.1 is not
satisfied, because the L/d is more predominant for the sound than
the t/D, at least the condition of 0<L/d.ltoreq.14 has only to
be satisfied. That is, at least the condition of 0<L/d.ltoreq.14
is satisfied, the other condition such as the t/D may be suitably
changed without being limited.
[0115] Furthermore, the structure of the nozzle portion 2 is not
limited to the structure shown in each figure or/and described in
the above embodiments, but various structures, such as a Laval
nozzle or a tapered nozzle, can be employed.
[0116] In the above-described embodiments, the ejector 1 is used
for the refrigerant cycle device shown in FIG. 1. However, the
ejector 1 can be used for other refrigerant cycle device. For
example, the ejector 1 may be used for a refrigerant cycle device
having a vapor-liquid separator and a refrigerant passage through
which liquid refrigerant of the vapor-liquid separator is
introduced to the refrigerant suction port 3a via an evaporator,
without using the branch passage 16.
[0117] That is, the ejector 1 can be used for a refrigerant cycle
device which includes a compressor for sucking and compressing
refrigerant, a radiator for radiating high-pressure refrigerant
discharged from the compressor, the ejector 1 having the nozzle
portion 2 for decompressing the refrigerant from the radiator, and
an evaporator for evaporating refrigerant to be drawn into the
refrigerant suction port 3a by the jet flow of the refrigerant
jetted from the nozzle outlet 2b. The refrigerant cycle device may
be operated with both the refrigerant driving flow and the
refrigerant suction flow in the ejector 1, or may be operated with
only the refrigerant driving flow in the ejector 1.
[0118] Furthermore, the above embodiments can be suitably combined
in the structure of the ejector 1.
[0119] Such changes and modifications are to be understood as being
within the scope of the present invention as defined by the
appended claims.
* * * * *