U.S. patent application number 13/126961 was filed with the patent office on 2011-09-01 for oil separator built-in compressor.
Invention is credited to Ippei Goto, Sadaaki Kajimoto, Toshiaki Kazama, Tatsuki Nomura, Yuuji Oiwake, Toshimi Watanabe.
Application Number | 20110211977 13/126961 |
Document ID | / |
Family ID | 42128975 |
Filed Date | 2011-09-01 |
United States Patent
Application |
20110211977 |
Kind Code |
A1 |
Nomura; Tatsuki ; et
al. |
September 1, 2011 |
Oil Separator Built-In Compressor
Abstract
Provided is an oil separator built-in compressor, which prevents
a drop in the separating ability of an oil separator while reducing
a pressure loss in a communication hole formed between a discharge
chamber and an oil separation chamber and which also considers the
working feasibility of a casing. The oil separator built-in
compressor comprises: a separation chamber arranged adjacent to the
discharge chamber and formed entirely thereof into a space in order
to separate an oil-containing gas being introduced, centrifugally
into gas and oil so that the separated oil flows downward whereas
the separated gas is released upward; and the communication hole
formed between the discharge chamber and the separation chamber in
order to introduce the oil-containing gas from the discharge
chamber into the separation chamber. The oil separator built-in
compressor is characterized in that the oil separator is formed of
the joint structure of two members for constituting the compressor,
and in that a portion of the inner wall face of the communication
hole is formed at a position farther from the joining face of the
joint structure than the inner wall face of the separation
chamber.
Inventors: |
Nomura; Tatsuki; (Gunma,
JP) ; Oiwake; Yuuji; (Gunma, JP) ; Watanabe;
Toshimi; (Gunma, JP) ; Kajimoto; Sadaaki;
(Gunma, JP) ; Kazama; Toshiaki; (Gunma, JP)
; Goto; Ippei; (Gunma, JP) |
Family ID: |
42128975 |
Appl. No.: |
13/126961 |
Filed: |
October 29, 2009 |
PCT Filed: |
October 29, 2009 |
PCT NO: |
PCT/JP2009/068944 |
371 Date: |
April 29, 2011 |
Current U.S.
Class: |
417/313 |
Current CPC
Class: |
F04C 18/0215 20130101;
F01C 21/10 20130101; F04C 29/026 20130101 |
Class at
Publication: |
417/313 |
International
Class: |
F04B 53/00 20060101
F04B053/00 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 29, 2008 |
JP |
2008-278753 |
Claims
1. An oil separator built-in compressor comprising: a separation
chamber which is arranged adjacent to a discharge chamber and an
inside of which is formed entirely into a space so as to separate
an oil-containing gas introduced, centrifugally into gas and oil so
that a separated oil flows downward whereas a separated gas is
released upward; and a communication hole, which is formed between
said discharge chamber and said separation chamber and which
introduces said oil-containing gas from said discharge chamber into
said separation chamber, characterized in that an oil separator is
formed from a joint structure of two members for constituting a
compressor, and in that a portion of an inner wall surface of said
communication hole is formed at a position farther from a joining
face of said joint structure than said inner wall surface of said
separation chamber.
2. The oil separator built-in compressor according to claim 1,
wherein said communication hole is formed at a position farthest
from said joining face of said joint structure.
3. The oil separator built-in compressor according to claim 1,
wherein a plural of said communication holes are arrayed in a
vertical direction.
4. The oil separator built-in compressor according to claim 3,
wherein said communication holes are opened in a same direction
toward said separation chamber.
5. The oil separator built-in compressor according to claim 3,
wherein said communication holes are opened in different directions
toward said separation chamber.
6. The oil separator built-in compressor according to claim 3,
wherein said communication holes are formed so as to make an array
pitch P [mm] of said communication holes and a vertical width W
[mm] of each communication hole satisfy a following formula:
W+2.ltoreq.P.ltoreq.W+7.
7. The oil separator built-in compressor according to claim 1,
provided with said oil separator which has a lower hole to deliver
said oil separated in said separation chamber into an oil storing
chamber located below said separation chamber.
8. The oil separator built-in compressor according to claim 1,
wherein said separation chamber is formed into a cylindrical shape
of which bus part extends linearly.
9. The oil separator built-in compressor according to claim 1,
wherein said separation chamber is formed into a cylindrical shape
of which bus part curves.
10. The oil separator built-in compressor according to claim 1,
wherein a compressor is a scroll type compressor, wherein one of
said two members is a fixed scroll forming member and another is a
compressor casing.
11. The oil separator built-in compressor according to claim 1,
wherein a compressor is a compressor for an automotive air
conditioning system.
Description
TECHNICAL FIELD OF THE INVENTION
[0001] The present invention relates to an oil separator built-in
compressor, and specifically relates to an oil separator built-in
compressor which is designed to achieve simplification and
downsizing of an oil separator mechanism, reduction of the number
of parts, ease of assembling and low pressure loss.
BACKGROUND ART OF THE INVENTION
[0002] Patent document 1 discloses a conventional oil separator
built-in compressor, which incorporates an centrifugal oil
separator in a compressor which is installed in a refrigeration
system for automotive air conditioning devices. In a conventional
oil separator built-in compressor, when gas including oil in
discharge chamber 2 is introduced into oil separation chamber 7
through communication hole 18 and the gas whirls along an inner
wall surface of oil separation chamber 7, centrifugal force is
generated so as to separate the gas and the oil, as shown in FIG. 6
with an example of cross section structure of conventional oil
separation chamber 7. In Patent document 1, oil separation chamber
7 is formed with a structure where fixed scroll member 5 and casing
6 are put together on joining face 11. In FIG. 6(b), symbol 18a
indicates an upper communication hole as one of communication holes
which are arrayed in a vertical direction. On the other hand,
symbol 18b indicates a lower communication hole. [0003] Patent
document 1: JP2008-82238-A
DISCLOSURE OF THE INVENTION
Problems to be Solved by the Invention
[0004] They are trying to reduce pressure loss by extending the
cross section of the communication hole in order to meet the latest
needs of greater discharge volume of compressors. However, if the
communication hole is simply extended with the above-described
conventional structure, the following trouble might occur.
[0005] When a plural of communication holes 18 are formed in a
conventional oil separator built-in compressor having the
above-described structure, the extension of cross section of
communication holes 18 might make walls between adjacent
communication holes 18 too thin, so as to make it difficult to form
casing 6 by casting or forging. In order to keep sufficient wall
thickness of the walls between adjacent communication holes, the
position of lower communication hole 18b may be lowered, for
example. However, if lower communication hole 18b is located at
lower position below oil separation chamber 7, sufficient gas
whirling region to separate the oil becomes smaller, and the oil
separation ability of the oil separator may decrease.
[0006] Focusing on the above-described problems, an object of the
present invention is to provide an oil separator built-in
compressor which can reduce the pressure loss at the communication
holes between the discharge chamber and the oil separation chamber
and of which casing can be easily formed.
Means for Solving the Problems
[0007] In order to achieve the above-described object, an oil
separator built-in compressor according to the present invention is
an oil separator built-in compressor comprising:
[0008] a separation chamber which is arranged adjacent to a
discharge chamber and an inside of which is formed entirely into a
space so as to separate an oil-containing gas introduced,
centrifugally into gas and oil so that the separated oil flows
downward whereas the separated gas is released upward; and
[0009] a communication hole, which is formed between the discharge
chamber and the separation chamber and which introduces the
oil-containing gas from the discharge chamber into the separation
chamber,
[0010] characterized in that an oil separator is formed from a
joint structure of two members for constituting the compressor, and
in that a portion of the inner wall surface of the communication
hole is formed at a position farther from the joining face of the
joint structure than the inner wall surface of the separation
chamber.
[0011] The oil separator built-in compressor according to the
present invention makes it possible to constitute the separation
chamber of the oil separator with a simple and compact structure
because the oil separator is formed with a joint structure of two
members in the oil separator built-in compressor having a
communication hole which is formed between the discharge chamber
and the separation chamber and which introduces the oil-containing
gas from the discharge chamber into the separation chamber. It also
makes it possible to reduce the pressure loss because the portion
of the inner wall surface of the communication hole is formed at a
position farther from the joining face of the joint structure than
the inner wall surface of the separation chamber so that the
communication hole is formed at a conventional position to maintain
the separation ability at a predetermined level and the cross
section of the communication hole has been enlarged.
[0012] In the present invention, it is desirable that the
communication hole is formed at a position farthest from the
joining face of the joint structure. Here, to be farthest from the
joining face means that the distance from the joining face is the
longest in the member on which the communication hole is machined.
Such formed communication hole makes it possible that dead spaces
of gas flow are not likely to appear when the oil-containing gas is
introduced from the communication hole into the separation chamber,
so that the gas which is flowed into the separation chamber is
given superior centrifugal separation performance.
[0013] In addition, the present invention shows a great advantage
particularly if a plural of the communication holes are arrayed in
the vertical direction. In other words, machining the casing by
casting and forging becomes less difficult because the pressure
loss can be reduced without changing the array pitch of adjacent
communication holes when the cross section of communication holes
arrayed in the vertical direction is enlarged.
[0014] Further, the communication holes can be formed with a
structure where the communication holes are opened in the same
direction toward the separation chamber. In such a case, even if
the amount of gas blown into the oil separation chamber is
relatively large, each direction for blowing of gas through each
communication holes can be optimized, so that centrifugal
separation is performed efficiently in the separation chamber and
efficiently introduces separated oil into the oil storage chamber.
Alternatively, the structure can be a structure where the
communication holes are opened in different directions toward the
separation chamber. In such a case, each direction of gas blowing
into the oil separation chamber can be set at a different angle
according to each communication hole. Therefore the gas blowing
direction can be set as suitable to the shape of the oil separation
chamber, so that the gas blown from each communication hole is
efficiently separated centrifugally to introduce the efficiently
separated oil into the oil storing chamber.
[0015] Further, it is desirable that the communication holes are
formed so as to make an array pitch P [mm] of the communication
holes and a vertical width W [mm] of each communication hole
satisfy the following formula.
W+2.ltoreq.P.ltoreq.W+7
[0016] The above-described formula has the following meaning. It
means that the array pitch is preferably not less than 2 mm in
addition to vertical width W of each communication hole from a
viewpoint of casting process of the casing. In other words, the
wall thickness is preferably not less than 2 mm between adjacent
communication holes, and the array pitch is preferably not more
than 7 mm in addition to vertical width W of each communication
hole so as to sufficiently achieve the air curtain effect in the
separation chamber. Here, the air curtain effect is an effect to
prevent the separated oil from flowing upward together with an
upflow of gas by a twisting curtain-like flow of stable gas flow
along the inner wall of the separation chamber.
[0017] More concretely, it is possible that the oil separator
built-in compressor according to the present invention has the oil
separator which has a lower hole to deliver the oil separated in
the separation chamber into an oil storing chamber located below
the separation chamber. Because such a lower hole can be formed
with a joint structure of two members composing the compressor,
great improvement of productivity and cost reduction are
expected.
[0018] Because the oil separator built-in compressor of which the
oil separator is formed with a joint structure of two members is
made of small number of component parts and has no portion to be
machined, the shape of the separation chamber can be extremely
freely formed. Therefore, the separation chamber can be formed into
a cylindrical shape of which bus part extends linearly, and
alternatively into a cylindrical shape, such as a donut shape as a
whole (a partial donut shape), of which bus part curves.
[0019] Though the cross-sectional shape of the curving cylindrical
shape is preferably a substantively perfect circle, the joint
structure of two members may have either a step on the inner
surface of the cylindrical shape or a difference of curvature
between the arcs in the cross-section of the cylindrical shape of
members forming the inner surface of the cylindrical shape.
Further, there can be a circumferential difference of inner surface
between both members forming the inner surface of the cylindrical
shape. Furthermore, there can be a differential depth of circular
groove in the cross-section of the cylindrical shape between both
members forming the inner surface of the cylindrical shape.
[0020] The oil separator built-in structure of the present
invention is applicable to all types of compressors substantively,
and is specifically suitable for a scroll type compressor. A
structure, where one of the two members is a fixed scroll forming
member and the other is a compressor casing, can be applied to a
scroll type compressor, for example.
[0021] The oil separator built-in compressor according to the
present invention can be used as a compressor for an automotive air
conditioning system because the oil separator is formed with a
joint structure of two members for constituting the compressor and
therefore is easy to reduce its size and weight.
Effect According to the Invention
[0022] Thus, the oil separator built-in compressor according to the
present invention makes it possible that the cross-section of the
communication hole is enlarged so as to reduce pressure loss
without changing the array of communication hole in a conventional
structure and that component parts, such as casing provided with a
communication hole can be easily formed by casting or forging while
desirable centrifugal separation performance and processing
characteristics can be maintained. Furthermore, casting and forging
of which desirable separation performance and processing
characteristics have been maintained can be performed more surely,
when the array pitch of the communication holes is set within a
predetermined range. In addition, the oil separator built-in
compressor of the present invention is suitably used as a
compressor for an automotive air conditioning system because the
oil separator has a joint structure which is easy to reduce its
size and weight.
BRIEF EXPLANATION OF THE DRAWINGS
[0023] FIG. 1 is a longitudinal sectional view showing a joint
structure of an oil separator built-in compressor according to an
embodiment of the present invention.
[0024] FIG. 2 is a cross sectional view showing the compressor
shown in FIG. 1, where (a) shows a cross section viewed in A-A
direction and (b) shows a cross section viewed in B-B
direction.
[0025] FIG. 3 is a cross sectional view showing a separation
chamber of the compressor shown in FIG. 2, where (a) shows a cross
section of the separation chamber viewed from the upper side of
FIG. 2 and (b) shows a cross section of the communication hole
viewed from the right side thereof.
[0026] FIG. 4 is an explanatory diagram for array pitch P of
communication holes and vertical width W of each communication
hole, where (a) shows an enlarged neighborhood of the separation
chamber in FIG. 2(b) and (b) is one corresponding to FIG. 3(b).
[0027] FIG. 5 is an explanatory diagram for whirling gas flow
generated in a separation chamber of oil separator built-in
compressor according to the present invention, where (a) shows a
case where upper and lower communication holes are sufficiently
close and (b) shows another case where upper and lower
communication holes are sufficiently apart.
[0028] FIG. 6 is a cross sectional view showing a separation
chamber of a conventional oil separator built-in compressor, where
(a) shows a cross section of a separation chamber and (b) shows a
cross section of a communication hole viewed from the right
side.
EXPLANATION OF SYMBOLS
[0029] 1: oil separator built-in compressor [0030] 2: discharge
chamber [0031] 3: second discharge chamber [0032] 4: oil trap
chamber [0033] 5 fixed scroll member [0034] 6: casing [0035] 7:
separation chamber [0036] 8, 18: communication hole [0037] 8a, 18a:
upper communication hole [0038] 8b, 18b: lower communication hole
[0039] 9: lower side hole [0040] 10: gas passageway [0041] 11:
joining face [0042] 12: oil separator
THE BEST MODE FOR CARRYING OUT THE INVENTION
[0043] Hereinafter, desirable embodiments will be explained as
referring to figures.
[0044] FIG. 1 is a longitudinal sectional view showing a joint
structure of an oil separator built-in compressor according to an
embodiment of the present invention. Compressor 1 is a scroll type
compressor where discharge chamber 2, second discharge chamber 3
and oil trap chamber 4 are formed with a joint structure between
fixed scroll member 5 and casing 6.
[0045] FIG. 2 shows a cross section of compressor 1 shown in FIG.
1, where (a) is a sectional view in A-A direction of FIG. 1 and (b)
is a sectional view in B-B direction of FIG. 1. As shown in FIG.
2(b), upper communication hole 8a and lower communication hole 8b
are formed to connect discharge chamber 2 and separation chamber 7
by a joint structure between fixed scroll member 5 shown in FIG.
2(a) and casing 6 side which has been machined for forming
communication hole 8. On the other hand, lower hole 9 is formed to
connect separation chamber 7 and oil trap chamber 4 by a joint
structure between casing 6 side and fixed scroll member 5 side
which have been machined for forming lower hole 9. Oil-containing
compressed gas, which is compressed with a compression mechanism
and is introduced in discharge chamber 7, is introduced through
communication hole 8 into separation chamber 7 as forming a
whirling flow along an inner wall of separation chamber 7.
Preferably, the whirling flow forms a whirling flow which moves
down along the inner wall of separation chamber 7 and the oil in
the gas is separated from the gas by centrifugal separation with
the whirling flow. The separated oil moves down on the inner wall
of separation chamber 7 through lower hole 9 and is trapped in oil
trap chamber 4. On the other hand, the gas separated from the oil
is introduced via gas passageway 10 into second discharge chamber 3
as forming upward flow in the center of cross section of separation
chamber 7, so as to be discharged through a discharge port. In this
way, compressor 1 incorporates oil separator 12 provided with
separation chamber 7, communication hole 8, lower hole 9 and oil
trap chamber 4.
[0046] FIG. 3 shows a section of separation chamber 7 of compressor
1 shown in FIG. 2, where (a) is a cross sectional view of
separation chamber 7 viewed from the top side of FIG. 2 and (b) is
a cross sectional view of communication hole 8 viewed from the
right side of (a). As to communication hole 8 connecting discharge
chamber 2 and separation chamber 7, a part of the communication
hole inner wall surface is formed at a position farther from
joining face 11 than the inner wall surface of separation chamber
7, unlike the conventional compressor shown in FIG. 6.
Communication hole is apertured at a position which is the farthest
from joining face 11 of the above-described joint structure in the
inner wall surface of separation chamber 7. Here, being the
farthest from joining face 11 means that a distance from the
joining face 11 is the longest in a member where a portion for
forming communication hole 8 is machined. In FIG. 3, it corresponds
to points Q1 and Q2, positions of which distances are the longest
from joining face 11 at the side of casing 6 where the portion to
form communication hole 8 is supposed to be machined. Thus
communication hole 8 is formed as digging into the inner wall
surface of separation chamber 7 in the neighborhood of points Q1,
Q2. Therefore, cross-sectional area of each communication hole 8a,
8b can be scaled up without changing the vertical position of
communication holes 8a and 8b arrayed as shown in FIG. 2(b), so
that pressure loss can be reduced.
[0047] FIG. 4 is an explanatory diagram for array pitch P of
communication holes 8 and vertical width W of each communication
hole 8, where (a) shows an enlarged neighborhood of separation
chamber 7 in FIG. 2(b) and (b) is one corresponding to FIG. 3(b).
It can be found from the Figs that when P equals to W+2 wall
thickness between adjacent communication holes 8 will be 2 mm and
that when P equals to W+7 wall thickness between adjacent
communication holes 8 will be 7 mm. It is preferable that the
formula P.gtoreq.W+2 is satisfied from the viewpoint of machining
of casing 6 on which communication hole 8 is formed. On the other
hand, it is preferable that the formula P.ltoreq.W+7 is satisfied
from the viewpoint of advancing an air curtain effect.
[0048] FIG. 5 is an explanatory diagram for whirling gas flow
generated in separation chamber 7 of oil separator built-in
compressor according to the present invention, where (a) shows a
case where upper communication hole 8a and lower communication hole
8b are sufficiently close, and (b) shows another case where upper
communication hole 8a and lower communication hole 8b are
sufficiently apart. In FIG. 5(a) oil-containing gas introduced from
lower communication hole 8b is whirling toward lower hole 9 below
separation chamber 7 as being affected by an air curtain effect
which is generated by the whirling flow of oil-containing gas
introduced from upper communication hole 8a. On the other hand, in
FIG. 5(b) whirling flow is not strong enough to generate sufficient
air curtain effect. Therefore some oil-containing gas introduced
from lower communication hole 8b into separation chamber 7 whirls
toward the side of gas passageway 10 above separation chamber 7 in
vain, so that the oil separation performance of oil separator 12
deteriorates. Thus the size of array pitch P of communication hole
8 affects separation performance of oil separator 12. As explained
with FIG. 4, when array pitch P is defined as satisfying the
relation of P.ltoreq.W+7, air curtain effect as shown in FIG. 5(b)
rather than FIG. 5(a) is achieved so as to ensure the separation
performance of oil separator 12.
INDUSTRIAL APPLICATIONS OF THE INVENTION
[0049] The composition of an oil separator built-in compressor
according to the present invention is applicable to any type of
compressors incorporating an oil separator, and suitable for a
scroll-type compressor.
* * * * *