U.S. patent application number 12/840368 was filed with the patent office on 2011-01-27 for turbo compressor and refrigerator.
Invention is credited to Kentarou ODA, Minoru TSUKAMOTO.
Application Number | 20110016916 12/840368 |
Document ID | / |
Family ID | 43496105 |
Filed Date | 2011-01-27 |
United States Patent
Application |
20110016916 |
Kind Code |
A1 |
TSUKAMOTO; Minoru ; et
al. |
January 27, 2011 |
TURBO COMPRESSOR AND REFRIGERATOR
Abstract
A turbo compressor includes an impeller; compression stages
having scroll chambers which introduce the refrigerant to the
impeller or lead the refrigerant compressed by the rotation of the
impeller to the outside; and an oil tank in which a heater is
disposed and an lubricant oil is stored, and at least a part of the
scroll chambers is disposed in the vicinity of the oil tank.
Inventors: |
TSUKAMOTO; Minoru;
(Yokohama-shi, JP) ; ODA; Kentarou; (Yokohama-shi,
JP) |
Correspondence
Address: |
OSTROLENK FABER GERB & SOFFEN
1180 AVENUE OF THE AMERICAS
NEW YORK
NY
100368403
US
|
Family ID: |
43496105 |
Appl. No.: |
12/840368 |
Filed: |
July 21, 2010 |
Current U.S.
Class: |
62/498 |
Current CPC
Class: |
F04D 29/063 20130101;
F25B 1/053 20130101; F25B 31/002 20130101; F25B 2400/01
20130101 |
Class at
Publication: |
62/498 |
International
Class: |
F25B 1/00 20060101
F25B001/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 21, 2009 |
JP |
P2009-170191 |
Claims
1. A turbo compressor comprising: a case having sliding parts; an
impeller which is connected to a shaft portion supported by the
sliding parts and rotates around an axis; a plurality of
compression stages having scroll chambers which introduce a fluid
into the impeller or lead the fluid compressed by the rotation of
the impeller to the outside, and an oil tank in which a heating
source is disposed and lubricant oils, which are supplied to the
sliding parts, is stored, wherein at least a part of the scroll
chambers is disposed in the vicinity of the oil tank.
2. The turbo compressor according to claim 1, wherein at least a
part of the scroll chambers is disposed under the oil surface of
the lubricant oil which is stored within the oil tank.
3. A refrigerator comprising: a condenser that cools and liquefies
a compressed refrigerant; an evaporator which cools a material to
be cooled by evaporating the liquefied refrigerant to take the
vaporization heat from the material to be cooled; and a turbo
compressor which compresses the refrigerant evaporated by the
evaporator to supply the refrigerant to the condenser, wherein the
turbo compressor according to claim 1 or 2 is used as the turbo
compressor.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a turbo compressor and a
refrigerator. More specifically, the present invention relates to a
turbo compressor capable of compressing a fluid by a plurality of
impellers and a refrigerator including the turbo compressor.
[0003] Priority is claimed on Japanese Patent Application No.
2009-170191, filed Jul. 21, 2009, the content of which is
incorporated herein by reference.
[0004] 2. Description of Related Art
[0005] As a refrigerator for cooling or refrigerating a material to
be cooled such as water, there is known a turbo refrigerator or the
like including a turbo compressor which compresses and discharges
the refrigerant by means of a compressing means equipped with an
impeller or the like. In the compressor, when the compression ratio
increases, the discharging temperature of the compressor rises and
the volumetric efficiency declines. Thus, in the turbo compressor
included in the turbo refrigerator or the like as described above,
the compression of the refrigerant is often performed so as to be
divided into a plurality of stages (for example, see PCT Japanese
Translation Patent Publication No. 2008-506885).
[0006] In such a turbo compressor, a spiral scroll chamber for
leading the compressed refrigerant to the outside of the compressor
or for introducing the refrigerant into the inside of the
compressor to compress the refrigerant is disposed. Furthermore,
the lubricant oil is supplied from an oil tank to sliding parts
such as a bearing for rotatably supporting an impeller or the
like.
[0007] In the turbo compressor and the refrigerator of the related
art as described above, when the operation is stopped for a long
time, the refrigerant is condensed at the lower part in the scroll
chamber. For this reason, before the operation of the compressor
restarts, there is a need for an operation of discharging the
condensed refrigerant liquid from a drain port disposed or the like
under the scroll chamber to the outside, which becomes
complicated.
SUMMARY OF THE INVENTION
[0008] The present invention provides a turbo compressor and a
refrigerator which can automatically discharge the refrigerant from
the inside of the scroll chamber to rapidly restart the operation,
even if the refrigerant is condensed in the scroll chamber for a
long-term operation stop.
[0009] According to a first aspect of the present invention, a
turbo compressor relating to the present invention includes a case
having sliding parts, an impeller which is connected to a shaft
portion supported by the sliding part and rotates around an axis, a
plurality of compression stages having scroll chambers which
introduce the fluid into the impeller or leads the fluid compressed
by the rotation of the impeller to the outside, and an oil tank in
which a heating source is disposed and an lubricant oil to be
supplied to the sliding part is stored, wherein at least a part of
the scroll chambers is disposed in the vicinity of the oil
tank.
[0010] In the turbo compressor, at least a part of the scroll
chambers is disposed in the vicinity of the oil tank with the
heating source disposed thereon. For this reason, it is possible to
preferably transmit the heat of the lubricant heated before the
operation restart by the heating source oil from the wall surface
of the oil tank to the wall surface of the scroll chamber. In
addition, the fluid to be compressed, which has been condensed
within the scroll chamber, can be heated by the heat.
[0011] Thus, the work of discharging the condensed refrigerant
liquid from the drain port or the like disposed under the scroll
chamber to the outside is unnecessary, whereby the operation can
restart without any particular operations.
[0012] According to a second aspect of the present invention, in
the turbo compressor relating to the present invention, at least a
part of the scroll chamber is disposed under the oil surface of the
lubricant oil to be stored in the oil tank. According to the turbo
compressor, the heat of the heated lubricant oil can be more
preferably transmitted to the scroll chamber.
[0013] According to a third aspect of the present invention, a
refrigerator relating to the present invention includes a condenser
that cools and liquefies the compressed refrigerant; an evaporator
which cools a material to be cooled by evaporating the liquefied
refrigerant to take the vaporization heat from the material to be
cooled; and a turbo compressor which compresses the refrigerant
evaporated by the evaporator to supply the refrigerant to the
condenser, wherein the above-mentioned compressor is used as the
turbo compressor.
[0014] The refrigerator exhibits the same working effects as the
turbo compressor.
[0015] According to the present invention, even if the refrigerant
is condensed in the scroll chamber during operation stop, the
refrigerant can be automatically discharged from the inside of the
scroll chamber to rapidly restart the operation.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] FIG. 1 is a block diagram showing a schematic configuration
of a turbo refrigerator relating to an embodiment of the present
invention.
[0017] FIG. 2 is a vertical sectional view of a turbo compressor
included in the turbo refrigerator relating to an embodiment of the
present invention.
[0018] FIG. 3 is a sectional view taken from lines III-III in FIG.
2.
[0019] FIG. 4 is a sectional view taken from lines IV-IV in FIG.
2.
DETAILED DESCRIPTION OF THE INVENTION
[0020] An embodiment of a turbo compressor and a refrigerator
relating to the present invention will be described with reference
to FIGS. 1 to 4.
[0021] A turbo refrigerator (a refrigerator) 1 relating to the
present embodiment is, for example, installed on a building or a
factory so as to create the cooling water for air conditioning. As
shown in FIG. 1, the turbo refrigerator 1 includes a condenser 2,
an economizer 3, an evaporator 5 and a turbo compressor 6.
[0022] The condenser 2 is supplied with a compression refrigerant
gas X1, which is a refrigerant (a fluid) such as R134a compressed
in a gas state, and makes the compression refrigerant gas X1 a
refrigerant liquid X2 by cooling and liquefying the compression
refrigerant gas X1. As shown in FIG. 1, the condenser 2 is
connected to the turbo compressor 6 via a flow path R1 through
which the compression refrigerant gas X1 flows. In addition, the
condenser 2 is connected to the economizer 3 via a flow path R2
through which the refrigerant liquid X2 flows. An expansion valve 7
for decompressing the refrigerant liquid X2 is installed on the
flow path R2.
[0023] The economizer 3 temporarily stores the refrigerant liquid
X2 which has been decompressed in the expansion valve 7. The
economizer 3 is connected to the evaporator 5 via a flow path R3
through which the refrigerant liquid X2 flows. Furthermore, the
economizer 3 is connected to the turbo compressor 6 via a flow path
R4 through which gaseous components X3 of the refrigerant generated
in the economizer 3 flow. An expansion valve 8 for further
decompressing the refrigerant liquid X2 is installed in the flow
path R3. The flow path R4 is connected to the turbo compressor 6 so
as to supply the gaseous components X3 to a second compression
stage 23 described below which is included in the turbo compressor
6.
[0024] The evaporator 5 cools a material to be cooled, such as
water, by evaporating the refrigerant liquid X2 to take the
vaporization heat from the material to be cooled. The evaporator 5
is connected to the turbo compressor 6 via a flow path R5 through
which a refrigerant gas X4 generated by the evaporation of the
refrigerant liquid X2 flows. The flow path R5 is connected to a
first compression stage 22 described below which is included in the
turbo compressor 6.
[0025] The turbo compressor 6 compresses the refrigerant gas X4 to
make it the compression refrigerant gas X1. As described above, the
turbo compressor 6 is connected to the condenser 2 via the flow
path R1 through which the compression refrigerant gas X1 flows.
Furthermore, the turbo compressor 6 is connected to the evaporator
5 via the flow path R5 through which the refrigerant gas X4
flows.
[0026] As shown in FIGS. 2 to 4, the turbo compressor 6 includes a
case 11 with a plurality of sliding parts 10, a plurality of
compression stages 12, and an oil tank 13 in which the lubricant
oil LO is stored.
[0027] The case 11 is divided into a motor housing 15, a compressor
housing 16 and a gear housing 17, and those parts are connected to
each other in a separable manner. On the motor housing 15, an
output shaft 18 which rotates around an axis O, and a motor 20,
which is connected to the output shaft 18 to drive the compression
stage 12, are disposed. The output shaft 18 is rotatably supported
by a first bearing 21 fixed to the motor housing 15. Herein, the
sliding parts 10 include not only the first bearing 21 but a second
bearing 26, a third bearing 27, a gear unit 28 or the like as
described below.
[0028] The compression stage 12 includes a first compression stage
22 which sucks and compresses the refrigerant gas X4 (see FIG. 1),
and a second compression stage 23 which further compresses the
refrigerant gas X4 compressed in the first compression stage 22 to
discharge the refrigerant gas X4 as the compression refrigerant gas
X1 (see FIG. 1). The first compression stage 22 is disposed on the
compressor housing 16. The second compression stage 23 is disposed
on the gear housing 17.
[0029] The first compression stage 22 has a plurality of first
impellers (impellers) 22a, a first diffuser 22b, a first scroll
chamber (a scroll chamber) 22c and a suction port 22d. The
plurality of first impellers 22a is fixed to a rotational shaft (a
shaft portion) 25, is driven for rotation around the axis O by
means of the motor 20, and imparts the speed energy to the
refrigerant gas X4 which is supplied from a thrust direction to
discharge the refrigerant gas X4 in a radial direction. The first
diffuser 22b compresses the refrigerant gas X4 by converting the
speed energy imparted to the refrigerant gas X4 by the first
impeller 22a into the pressure energy. The first scroll chamber
(the scroll chamber) 22c leads the refrigerant gas X4 compressed by
the first diffuser 22b to the outside of the first compression
stage 22. The suction port 22d sucks the refrigerant gas X4 to
supply the same to the first impeller 22a. The first diffuser 22b,
the first scroll chamber 22c and a part of the suction port 22d is
formed by a first housing 22e surrounding the first impeller
22a.
[0030] A plurality of inlet guide vanes 22g for adjusting the
suction capacity of the first compression stage 22 is installed in
the suction port 22d of the first compression stage 22. The
respective inlet guide vanes 22g can rotate so that external areas
from the flow direction of the refrigerant gas X4 can be altered by
means of a driving mechanism 22i.
[0031] In the first housing 22e which is the outer peripheral
portion of the first impeller 22a in the first compression stage 22
and the suction port 22d at the upstream side thereof, a relay
space 22h, which forms a ring shape centered on the axis O, is
dividedly formed. A driving mechanism 22i for driving the inlet
guide vane 22g is housed inside the relay space 22h.
[0032] The relay space 22h communicates with the rear surface side
of the inlet guide vane 22g in the suction port 22d via a slight
gap 22j. As a result, it is configured such that the pressure of
the relay space 22h is always equal to that of the suction port
22d.
[0033] The second compression stage 23 includes a second impeller
(an impeller) 23a, a second diffuser 23b, a second scroll chamber
(a scroll chamber) 23c and an inlet scroll chamber (a scroll
chamber) 23d. The second impeller 23a imparts the speed energy to
the refrigerant gas X4, which is compressed in the first
compression stage 22 and is supplied from the thrust direction, to
discharge the refrigerant gas X4 in the radial direction. The
second diffuser 23b compresses the refrigerant gas X4 by converting
the speed energy imparted to the refrigerant gas X4 by the second
impeller 23a to the pressure energy to discharge the refrigerant
gas X4 as the compression refrigerant gas X1. The second scroll
chamber 23c leads the compression refrigerant gas X1 discharged
from the second diffuser 23b to the outside of the second
compression stage 23. The inlet scroll chamber 23d guides the
refrigerant gas X4 compressed in the first compression stage 22 to
the second impeller 23a. Herein, the second diffuser 23b, the
second scroll chamber 23c and a part of the inlet scroll chamber
23d is formed by a second housing 23e surrounding the second
impeller 23a.
[0034] The second impeller 23a is fixed to the rotational shaft 25
such that the rear surface thereof is mated with that of the first
impeller 22a, and the rotational movement force from the output
shaft 18 of the motor 20 is transmitted to the rotational shaft 25,
so that the rotational shaft 25 rotates around the axis O, whereby
the second impeller 23a is driven for rotation. The second diffuser
23b is disposed around the second impeller 23a in the shape of a
ring.
[0035] The second scroll chamber 23c is connected to the flow path
R1 for supplying the condenser 2 with the compression refrigerant
gas X1 to supply the flow path R1 with the compression refrigerant
gas X1 led from the second compression stage 23.
[0036] In addition, the first scroll chamber 22c of the first
compression stage 22 and the inlet scroll chamber 23d of the second
compression stage 23 are connected with each other via an outside
piping (not shown) which is provided separately from the first
compression stage 22 and the second compression stage 23, whereby
the refrigerant gas X4 compressed in the first compression stage 22
is supplied to the second compression stage 23 via the outside
piping. The above-mentioned flow path R4 (see FIG. 1) is connected
to the outside piping, whereby the gaseous components X3 of the
refrigerant generated in the economizer 3 is supplied to the second
compression stage 23 via the outside piping.
[0037] The rotational shaft 25 is rotatably supported by the second
bearing 26 fixed to the gear housing 17 and the third bearing 27
fixed to the compressor housing 16 in a rotatable manner with
respect to the case 11.
[0038] In the gear housing 17, an accommodation space S1 is formed
which accommodates a gear unit 28 for transmitting the driving
force of the output shaft 18 to the rotational shaft 25.
[0039] The oil tank 13 is formed and disposed so as to extend from
the lower part of the accommodation space S1 to the lower part of
the compressor housing 16. The first scroll chamber 22c, the second
scroll chamber 23c and the lower part sides of the inlet scroll
chamber 23d are disposed so as to be lower than the oil surface L
of the lubricant oil LO stored in the oil tank 13.
[0040] A heater (a heating source) 30 for heating the lubricant oil
LO to a prescribed temperature is disposed in the oil tank 13.
[0041] The gear unit 28 includes a low speed gear 31 fixed to the
output shaft 18 of the motor 20, and a high speed gear 32 which is
fixed to the rotational shaft 25 and is engaged with the low speed
gear 31. In addition, the rotational movement force of the output
shaft 18 of the motor 20 is transmitted to the rotational shaft 25
such that the revolution count of the rotational shaft 25 increases
with respect to the revolution count of the output shaft 18.
[0042] Next, the operations of the turbo refrigerator 1 and the
turbo compressor 6 relating to the present embodiment will be
described.
[0043] First of all, along with the operation start of the turbo
refrigerator 1 and the turbo compressor 6, the lubricant oil LO is
supplied from the oil tank 13 to the sliding parts 10 by means of
an oil pump (not shown). Then, the motor 20 is driven, so that the
rotational movement force of the output shaft 18 of the motor 20 is
transmitted to the rotation shaft 25 via gear unit 28. As a result,
the first compression stage 22 and the second compression stage 23
are driven for rotation.
[0044] When the first compression stage 22 is driven for rotation,
the suction port 22d of the first compression stage 22 enters a
negative pressure state, whereby the refrigerant gas X4 from the
flow path R5 flows in the first compression stage 22 via the
suction port 22d. At this time, the suction capacity is suitably
adjusted by means of the inlet guide vane 22g.
[0045] The refrigerant gas X4, which has flowed in the first
compression stage 22, flows in the first impeller 22a from the
thrust direction, is imparted with the speed energy by the first
impeller 22a and is discharged in the radial direction.
[0046] The speed energy of the refrigerant gas X4 discharged from
the first impeller 22a is converted to the pressure energy by the
first diffuser 22b, so that the refrigerant gas X4 is compressed.
The refrigerant gas X4 discharged from the first diffuser 22b is
led to the outside of the first compression stage 22 via the first
scroll chamber 22c.
[0047] In addition, the refrigerant gas X4 led to the outside of
the first compression stage 22 is supplied to the second
compression stage 23 via the outside piping.
[0048] The refrigerant gas X4 supplied to the second compression
stage 23 flows in the second impeller chamber 23a from the thrust
direction via the inlet scroll chamber 23d and is discharged in the
radial direction imparted with the speed energy by the second
impeller 23a.
[0049] The speed energy of the refrigerant gas X4 discharged from
the second impeller 23a is converted to the pressure energy by the
second diffuser 23b, whereby the refrigerant gas X4 is further
compressed and becomes the compression refrigerant gas X1.
[0050] The compression refrigerant gas X1 discharged from the
second diffuser 23b is led to the outside of the second compression
stage 23 via the second scroll chamber 23c.
[0051] In addition, the compression refrigerant gas X1 led to the
outside of the second compression stage 23 is supplied to the
condenser 2 via the flow path R1.
[0052] In a case where R134a or the like is used as the refrigerant
liquid X2, since the condensation temperature is 30.degree. C. to
40.degree. C., when the turbo refrigerator 1 is stopped for a long
time, the refrigerants remaining as the gas in the first scroll
chamber 22c, the second scroll chamber 23c and the inlet scroll
chamber 23d are condensed in the lower part thereof.
[0053] When the operation restarts, the lubricant oil LO stored in
the oil tank 13 is heated to the condensation temperature or more
of the refrigerant by means of the heater 30. As a result, the heat
of the heated lubricant oil LO is transferred from the wall surface
of the oil tank 13 to the respective wall surfaces of the first
scroll chamber 22c, the second scroll chamber 23c and the inlet
scroll chamber 23d, so that the refrigerant, which was condensed in
the chamber, is heated. Thus, the refrigerant is evaporated and
becomes gas again.
[0054] According to the turbo refrigerator 1 and the turbo
compressor 6, the first scroll chamber 22c, the second scroll
chamber 23c and the lower part of the inlet scroll chamber 23d are
disposed in the vicinity of the oil tank 13. For that reason, when
the turbo compressor 6 starts, by heating the lubricant oil LO
stored in the oil tank 13 with the heater 30, the refrigerants,
which are condensed in the first scroll chamber 22c, the second
scroll chamber 23c and the inlet scroll chamber 23d, are heated and
evaporated, whereby the refrigerants can be automatically
discharged from the chamber.
[0055] At this time, the first scroll chamber 22c, the second
scroll chamber 23c and the lower part of the inlet scroll chamber
23d are disposed at the part lower than the oil surface L of the
lubricant oil LO which is stored in the oil tank 13. Thus, the heat
of the heated lubricant oil LO can be further preferably
transmitted.
[0056] Furthermore, the technical scope of the present invention is
not limited to the above-mentioned embodiment, but various
modifications can be added without departing from the gist of the
present invention.
[0057] For example, in the above-mentioned embodiments, although
the configuration including the two compression stages (the first
compression stage 22 and the second compression stage 23) has been
described, the present invention is not limited thereto, but a
configuration including three or more compression stages may be
adopted.
[0058] In addition, the turbo compressor, in which the motor
housing 15, the compressor housing 16, and the gear housing 17 are
each dividedly formed as the case 11, has been described. However,
the present invention is not limited thereto, but, for example, a
configuration, in which the motor is disposed between the first
compression stage and the second compression stage, may be
adopted.
[0059] While preferred embodiments of the invention have been
described and illustrated above, it should be understood that these
are exemplary of the invention and are not to be considered as
limiting. Additions, omissions, substitutions, and other
modifications can be made without departing from the spirit or
scope of the present invention. Accordingly, the invention is not
to be considered as being limited by the foregoing description, and
is only limited by the scope of the appended claims.
* * * * *