U.S. patent application number 11/604258 was filed with the patent office on 2007-05-31 for rotary compressor.
This patent application is currently assigned to SANYO ELECTRIC CO., LTD.. Invention is credited to Kazuya Sato, Masaaki Takezawa.
Application Number | 20070122297 11/604258 |
Document ID | / |
Family ID | 37806105 |
Filed Date | 2007-05-31 |
United States Patent
Application |
20070122297 |
Kind Code |
A1 |
Sato; Kazuya ; et
al. |
May 31, 2007 |
Rotary compressor
Abstract
An object is to solve a problem that the smaller the number of
rotations of a rotary compressor is, the more an efficiency
decrease of the compressor is generated owing to an increase of a
rotary vibration and an efficiency decrease of a motor. In the
rotary compressor including, in a sealed vessel, a electromotive
element and a rotary compression element driven by this
electromotive element, on one of an upper end face of a rotor
constituting the electromotive element (on a side opposite to a
compression mechanism) and a lower end face of the rotor (on a
compression mechanism side), a rotation inertia article capable of
obtaining a rotation inertia moment is disposed. In consequence, it
is possible to obtain the compressor having a high efficiency in
which an increase of the rotary vibration of the compressor is
suppressed even during an operation having the small number of the
rotations of the compressor.
Inventors: |
Sato; Kazuya; (Gunma-ken,
JP) ; Takezawa; Masaaki; (Ota-shi, JP) |
Correspondence
Address: |
ARMSTRONG, KRATZ, QUINTOS, HANSON & BROOKS, LLP
1725 K STREET, NW
SUITE 1000
WASHINGTON
DC
20006
US
|
Assignee: |
SANYO ELECTRIC CO., LTD.
Moriguchi-shi
JP
|
Family ID: |
37806105 |
Appl. No.: |
11/604258 |
Filed: |
November 27, 2006 |
Current U.S.
Class: |
417/410.3 |
Current CPC
Class: |
F04C 29/0021 20130101;
F04C 2240/807 20130101; F04C 23/008 20130101; F04C 29/026 20130101;
F04C 18/3564 20130101; F04C 29/0085 20130101; F04C 23/001
20130101 |
Class at
Publication: |
417/410.3 |
International
Class: |
F04B 35/04 20060101
F04B035/04 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 28, 2005 |
JP |
341424/2005 |
Claims
1. A rotary compressor comprising: an electromotive element
disposed in a sealed vessel and including a stator and a rotor; a
rotary compression element driven by the electromotive element to
compress and discharge a refrigerant; and a rotary shaft which
connects the rotary compression element to the rotor of the
electromotive element and which is rotatably supported by a
bearing, wherein on the bottom of the rotor of the electromotive
element, a mass article is disposed which extends to a lower part
of the stator and which obtains a rotation inertia moment.
2. A rotary compressor comprising: an electromotive element
disposed in a sealed vessel and including a stator and a rotor; a
rotary compression element driven by the electromotive element to
compress and discharge a refrigerant; and a rotary shaft which
connects the rotary compression element to the rotor of the
electromotive element and which is rotatably supported by a
bearing, wherein on the top of the rotor of the electromotive
element, a mass article is disposed which extends to a lower part
of the stator and which obtains a rotation inertia moment.
3. The rotary compressor according to claim 1, wherein a motor
forming the electromotive element is of a direct winding type, and
the mass article disposed on the rotor is formed into a shape
having an outer diameter which is equal to or smaller than an outer
diameter of the rotor until a necessary insulation distance is
reached from a stator coil, and after the insulation distance, the
outer diameter of the shape is enlarged toward an inner wall of the
sealed vessel into such a size as to cover the stator coil.
4. The rotary compressor according to claim 1, wherein a discharge
port to discharge a compressed gas from the rotary compression
element into the sealed vessel is disposed in a position
corresponding to 1/2 or less of the maximum outer diameter of the
mass article disposed on the rotor.
5. The rotary compressor according to claim 2, wherein a motor
forming the electromotive element is of a direct winding type, and
the mass article disposed on the rotor is formed into a shape
having an outer diameter which is equal to or smaller than an outer
diameter of the rotor until a necessary insulation distance is
reached from a stator coil, and after the insulation distance, the
outer diameter of the shape is enlarged toward an inner wall of the
sealed vessel into such a size as to cover the stator coil.
6. The rotary compressor according to claim 2, wherein a discharge
port to discharge a compressed gas from the rotary compression
element into the sealed vessel is disposed in a position
corresponding to 1/2 or less of the maximum outer diameter of the
mass article disposed on the rotor.
7. The rotary compressor according to claim 3, wherein a discharge
port to discharge a compressed gas from the rotary compression
element into the sealed vessel is disposed in a position
corresponding to 1/2 or less of the maximum outer diameter of the
mass article disposed on the rotor.
8. The rotary compressor according to claim 5, wherein a discharge
port to discharge a compressed gas from the rotary compression
element into the sealed vessel is disposed in a position
corresponding to 1/2 or less of the maximum outer diameter of the
mass article disposed on the rotor.
Description
BACKGROUND OF THE INVENTION
[0001] The present invention relates to a rotary compressor
including, in a sealed vessel, a electromotive element, a rotary
compression element driven by a rotary shaft of this electromotive
element and a cantilever bearing which rotatably supports the
rotary shaft of this rotary compression element.
[0002] Heretofore, a rotary compressor such as a multistage
compression type rotary compressor including first and second
rotary compression elements includes, in a sealed vessel, a
electromotive element and the first and second rotary compression
elements driven by a rotary shaft of this electromotive
element.
[0003] An electromotive element is constituted of an annular stator
fixed along an inner peripheral surface which defines an upper
space of the sealed vessel by welding; and a rotor inserted in the
element so that a slight interval is disposed between the rotor and
an inner periphery of this stator. This rotor is fixed to the
rotary shaft passed through the center of the element in a vertical
direction.
[0004] Moreover, the first and second rotary compression elements
include an intermediate partition plate; upper and lower cylinders
disposed on and under this intermediate partition plate; rollers
which are fitted into eccentric portions disposed on the rotary
shaft with a phase difference of 180 degrees to eccentrically
rotate in these cylinders; vanes which abut on the rollers to
define the insides of the cylinders into low pressure chamber sides
and high pressure chamber sides, respectively; an upper support
member and a lower support member which block an upper opening
surface of the upper cylinder and a lower opening surface of the
lower cylinder and which have bearings of the rotary shaft,
respectively; and upper and lower discharge muffling chambers,
respectively. Each discharge muffling chamber is connected to the
high pressure chamber side in each cylinder by a discharge port. In
each discharge muffling chamber, a discharge valve is disposed
which openably blocks the discharge port (see, e.g., Japanese
Patent Application Laid-Open No. 2004-19599).
[0005] In the rotor of the conventional rotary compressor, a
rotation angular speed inversely proportional to a rotation inertia
moment is generated in proportion to a difference between a
compression torque and a torque of a motor, and a fluctuation
(reaction of the rotation angular speed) of the rotation angular
speed, which is inversely proportional to the rotation inertia
moment, is a cause for a rotary vibration of the rotary compressor.
The rotation angular speed of the rotor is an integral of the
rotation angular speed inversely proportional to the rotation
inertia moment with respect to a time. After one rotation, the
rotation angular speed returns to an original rotation angular
speed. Therefore, the smaller the number of the rotations of the
compressor is, the longer a time required for one rotation becomes.
Moreover, a fluctuation width of the rotation angular speed during
one rotation increases. Therefore, there is a problem that the
vibration of the compressor increases.
[0006] Furthermore, when there is a large fluctuation width of the
rotation angular speed during one rotation, a ratio increases at
which the compressor is operated in a rotation angular speed range
having a small efficiency, and an efficiency of the motor
decreases. Therefore, the smaller the number of the rotations of
the motor is, the more the efficiency of the compressor decreases.
When the compressor or the motor is miniaturized, the rotation
inertia moment decreases, and the increase of the compressor
vibration and the decrease of the efficiency easily appear.
SUMMARY OF THE INVENTION
[0007] A rotary compressor of a first invention has, in a sealed
vessel, a electromotive element, a compression mechanism driven by
this electromotive element and a cantilever bearing which rotatably
supports a rotary shaft of the electromotive element, and the
rotary compressor has, on the bottom of a rotor (on a compression
mechanism side), a mass article which extends to a lower part of a
stator and which obtains a rotation inertia moment.
[0008] Moreover, a rotary compressor of a second invention has, in
a sealed vessel, a electromotive element, a compression mechanism
driven by this electromotive element and a cantilever bearing which
rotatably supports a rotary shaft of the electromotive element, and
the rotary compressor has, on the top of a rotor (on a side
opposite to the compression mechanism), a mass article which
extends to a lower part of a stator and which obtains a rotation
inertia moment.
[0009] Furthermore, in a rotary compressor of a third invention,
the above inventions are characterized in that the mass article
disposed on the rotor is formed into a shape having an outer
diameter which is equal to or smaller than an outer diameter of the
rotor until a necessary insulation distance is reached from a
stator coil, and after the insulation distance, the outer diameter
of the shape is enlarged toward an inner wall of the sealed vessel
into such as size as to cover the stator coil.
[0010] In addition, in a rotary compressor of a fourth invention,
the above inventions are characterized in that a discharge port to
discharge a compressed gas from the rotary compression element into
the sealed vessel is disposed in a position corresponding to 1/2 or
less of the maximum outer diameter of the mass article disposed on
the rotor.
[0011] According to the first or second invention, the rotary
compressor comprises, in the sealed vessel, the electromotive
element, the rotary compression element driven by this
electromotive element and the cantilever bearing which rotatably
supports the rotary shaft of the electromotive element. The mass
article capable of obtaining the rotation inertia moment is
attached to one of an upper end face of the rotor (on the side
opposite to the compression mechanism) and a lower end face of the
rotor (on the compression mechanism side). In consequence, it is
possible to provide the compressor having a high efficiency in
which a vibration increase of the compressor is suppressed even
during an operation having the small number of rotations of the
compressor. Furthermore, the mass article to be attached extends
toward the stator. Therefore, when a dimension of the mass article
in a width direction is enlarged, a dimension of the article in a
thickness direction can be decreased, and the whole compressor can
be miniaturized in a height direction.
[0012] Moreover, in addition to the above inventions, according to
the third invention, the mass article disposed on the rotor is
formed into the shape having the outer diameter which is equal to
or smaller than the outer diameter of the rotor until the necessary
insulation distance from the stator coil is reached. After the
insulation distance, the outer diameter of the shape is enlarged
toward the inner wall of the sealed vessel into such a size as to
cover the stator coil. In consequence, a necessary rotation inertia
moment can be obtained.
[0013] Furthermore, in addition to the above inventions, according
to the fourth invention, the discharge port to discharge the
compressed gas from the rotary compression element into the sealed
vessel is disposed in the position corresponding to 1/2 or less of
the maximum outer diameter of the mass article disposed on the
rotor. In consequence, an oil in the discharged gas is separated by
the mass article, and an amount of the oil to be discharged from
the compressor can be decreased.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 is a vertically sectional view of a rotary compressor
in Embodiment 1 of the present invention (an example in which a
rotation inertia article is attached to a compression mechanism
side);
[0015] FIG. 2 is a vertically sectional view of the rotary
compressor in Embodiment 1 of the present invention (an example in
which a rotation inertia article is attached to a side opposite to
a compression mechanism);
[0016] FIG. 3 is a vertically sectional view of a rotary compressor
in Embodiment 2 of the present invention; and
[0017] FIG. 4 is an enlarged view showing positions of the rotation
inertia article and a discharge port in Embodiment 2 of the present
invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0018] The present invention is characterized in that a rotary
compressor having a high efficiency in which a vibration increase
of the compressor is suppressed even in a region having the small
number of rotations is realized by attaching a rotation inertia
article to a rotor. It is also possible to cope with a vibration
increase and an efficiency decrease due to miniaturization of the
compressor. A mass article disposed on the rotor is formed into a
shape having an outer diameter which is equal to or smaller than an
outer diameter of the rotor until a necessary insulation distance
is reached from a stator coil, and after the insulation distance,
the outer diameter of the shape is enlarged toward an inner wall of
a sealed vessel into such a size as to cover the stator coil. In
consequence, a necessary rotation inertia moment is obtained.
Moreover, a discharge port to discharge a compressed gas from a
rotary compression element into a sealed vessel is disposed in a
position corresponding to 1/2 or less of the maximum outer diameter
of the mass article disposed on the rotor. In consequence, an oil
contained in the discharged gas is separated by the mass article,
and an amount of the oil to be discharged from the compressor is
decreased.
Embodiment 1
[0019] Next, an embodiment of the present invention will be
described in detail with reference to the drawings. FIG. 1 shows a
vertically sectional view of a high inner pressure type rotary
compressor 10 as an embodiment of a rotary compressor of the
present invention. The rotary compressor includes first and second
rotary compression elements 32, 34, and a mass article, that is, a
rotation inertia article 82 attached to a rotor 24 with a rivet 73
on a compression mechanism side. FIG. 2 shows a vertically
sectional view of the rotary compressor 10 in a second
invention.
[0020] In FIG. 1, the rotary compressor 10 of the present
embodiment is the high inner pressure type rotary compressor 10
including, in a vertically cylindrical sealed vessel 12 constituted
of a steel plate, an electromotive element 14 as a driving element
disposed in an upper space of this sealed vessel 12; and a rotary
compression mechanism portion 18 constituted of the first and
second rotary compression elements 32, 34 disposed under this
electromotive element 14 and driven by a rotary shaft 16 of the
electromotive element 14. It is to be noted that in the rotary
compressor 10 of the present embodiment, carbon dioxide is used as
a refrigerant.
[0021] The sealed vessel 12 is constituted of a vessel main body
12A having a bottom part as an oil reservoir and containing the
electromotive element 14 and the rotary compression mechanism
portion; and a substantially bowl shaped end cap (lid body) 12B
which blocks an upper opening of this vessel main body 12A.
Moreover, a circular attachment hole 12D is formed in the top of
this end cap 12B, and a terminal (a wiring line is omitted) 20 for
supplying a power to the electromotive element 14 is attached to
this attachment hole 12D.
[0022] The electromotive element 14 is constituted of an annular
stator 22 fixed along an inner peripheral surface of an upper part
of the sealed vessel 12 by welding; the rotor 24 inserted in the
element so that a slight interval is disposed between the rotor and
an inner periphery of the stator 22; and the rotation inertia
article 82 attached to the rotor 24 with the rivet 73. The rotor 24
and the rotation inertia article 82 are fixed to the rotary shaft
16 extending through the center of the element in a vertical
direction.
[0023] Here, the rotation inertia article 82 is formed into a shape
having an outer diameter which is equal to or smaller than an outer
diameter of the rotor until the minimum necessary insulation
distance (changes with a voltage to be applied) is reached from a
stator coil 28, and after the insulation distance is reached, the
outer diameter of the shape is enlarged toward an inner wall of the
sealed vessel 12 into such a size as to cover the stator coil 28.
Since the outer diameter of the shape of the article is enlarged,
it is possible to obtain a large rotation inertia moment with a
small amount of a material.
[0024] Moreover, in this case, as the material of the rotation
inertia article 82, copper or a copper alloy is used. The article
is formed as a cast article, a forged article or a laminated
article formed by laminating plates of copper or the copper
alloy.
[0025] The stator 22 has a laminated article 26 constituted by
laminating donut-shaped electromagnetic steel plates; and the
stator coil 28 wound around teeth portions of this laminated
article 26 by a direct winding (concentrated winding) system.
Moreover, the rotor 24 is formed of a laminated article 30
constituted of electromagnetic steel plates in the same manner as
in the stator 22.
[0026] An intermediate partition plate 36 is sandwiched as an
intermediate partition member between the first rotary compression
element 32 and the second rotary compression element 34, the second
rotary compression element 34 as a second stage is disposed on the
side of the electromotive element 14 in the sealed vessel 12, and
the first rotary compression element 32 as a first stage is
disposed on a side opposite to the electromotive element 14. That
is, the first rotary compression element 32 and the second rotary
compression element 34 include a lower cylinder 40 as a first
cylinder and an upper cylinder 38 as a second cylinder which
constitute the first and second rotary compression elements 32, 34;
and the intermediate partition plate 36 interposed between the
cylinders 38 and 40 to block an (upper) opening of the lower
cylinder 40 on the side of the electromotive element 14 and a
(lower) opening of the upper cylinder 38 on a side opposite to the
electromotive element 14. The elements also include a first roller
48 and a second roller 46 which are fitted into first and second
eccentric portions 42, 44 disposed on the rotary shaft 16 with a
phase difference of 180 degrees in the upper and lower cylinders
38, 40 to eccentrically rotate in the cylinders 38, 40,
respectively; and vanes (not shown) which abut on the rollers 46,
48 to define the insides of the cylinders 38, 40 into low-pressure
chamber sides and high-pressure chamber sides, respectively. The
elements further include a lower support member 56 as a first
support member which blocks a (lower) opening of the lower cylinder
40 on the side opposite to the electromotive element 14 and which
has a bearing 56A of the rotary shaft 16; and an upper support
member 54 as a second support member which blocks an (upper)
opening of the upper cylinder 38 on the side of the electromotive
element 14 and which has a bearing 54A of the rotary shaft 16,
respectively. On outer sides of the bearings 54A, 56A of the upper
and lower support members 54, 56, there are arranged a cover 63
attached to the upper support member 54 to define a discharge
muffling chamber 62; and a blocking plate 68 to define an
intermediate pressure discharge muffling chamber 64 in the lower
support member 56, respectively.
[0027] The upper support member 54 and the lower support member 56
include suction passages 58, 60 which communicate with the upper
and lower cylinders 38, 40 via suction ports 160, 161; and the
discharge muffling chamber 62 and the intermediate pressure
discharge muffling chamber 64, respectively. The discharge muffling
chamber 62 is formed by depressing the surface of the upper support
member 54 on a side opposite to the upper cylinder 38, and blocking
this depressed portion with the cover 63 as described above. The
intermediate pressure discharge muffling chamber 64 is formed by
depressing the surface of the lower support member 56 on a side
opposite to the lower cylinder 40, and blocking this depressed
portion with the blocking plate 68 so that the chamber is defined
by the blocking plate 68. That is, the discharge muffling chamber
62 is blocked with the cover 63, and the intermediate pressure
discharge muffling chamber 64 is blocked with the blocking plate
68.
[0028] In this case, the bearing 54A is erected in the center of
the upper support member 54. Around the outer periphery of the
bearing 54A, the discharge muffling chamber 62 is defined by the
cover 63. A gas discharged from a discharge port (not shown) passes
through the discharge muffling chamber 62, and is discharged into
the sealed vessel 12 from a communication passage 65 as a
donut-shaped gap between an upper portion of the upper bearing 54A
and the cover 63.
[0029] Moreover, the bearing 56A is passed through the center of
the lower support member 56. The bearing 56A substantially has a
donut shape centering on the rotary shaft 16 and having a central
hole through which the rotary shaft 16 passes. In the outer
periphery of the bearing 56A, the intermediate pressure discharge
muffling chamber 64 is disposed. On the other hand, the blocking
plate 68 is formed of a donut-shaped circular steel plate, and
fixed to the lower support member 56 from below with bolts 80
attached to four portions of a peripheral part of the plate, and
the plate blocks an opening in the bottom of the intermediate
pressure discharge muffling chamber 64 which communicates with the
lower cylinder 40 of the first rotary compression element 32 by a
discharge port (not shown). The bolts 80 are bolts for assembling
the first and second rotary compression elements 32, 34, and
distant ends of the bolts engage with the upper cylinder 38. That
is, the upper cylinder is provided with screw grooves to be engaged
with screw heads formed on distant end portions of the bolts
80.
[0030] Here, there will be described a procedure to assemble the
rotary compression mechanism portion 18 constituted of the first
and second rotary compression elements 32, 34. First, the cover 63,
the upper support member 54 and the upper cylinder 38 are
positioned, and two upper bolts 78, 78 to be engaged with the upper
cylinder 38 are inserted from a cover 63 side (from above) in an
axial center direction (downwards) to integrate the cover, the
upper support member and the upper cylinder. In consequence, the
second rotary compression element 34 is assembled.
[0031] Next, the second rotary compression element 34 integrated
with the upper bolts 78 is inserted along the rotary shaft 16 from
an upper end. Next, the intermediate partition plate 36 is
assembled with the lower cylinder 40, inserted along the rotary
shaft 16 from a lower end, and aligned with the upper cylinder 38
already attached. Two upper bolts (not shown) to be engaged with
the lower cylinder 40 are inserted from the cover 63 side (from
above) in the axial center direction (downwards) to fix the
intermediate partition plate, the lower cylinder and the upper
cylinder.
[0032] Moreover, after the lower support member 56 is inserted
along the rotary shaft 16 from below, the blocking plate 68 is
similarly inserted along the rotary shaft 16 from the lower end to
close the depressed portion of the lower support member 56. The
four lower bolts 80 are inserted from a blocking plate 68 side
(from below) in the axial center direction (upwards), and the
distant end portions of the bolts are engaged with the screw
grooves formed in the upper cylinder 38, respectively, to assemble
the first and second rotary compression elements 32, 34. It is to
be noted that since the rotary shaft 16 is provided with the first
and second eccentric portions 42, 44, the components cannot be
attached to the rotary shaft 16 in an order other than the above
order. Therefore, the blocking plate 68 is finally attached to the
rotary shaft 16.
[0033] Thus, the second rotary compression element 34, the
intermediate partition plate 36, the lower cylinder 40, the lower
support member 56 and the blocking plate 68 are successively
attached to the rotary shaft 16, and the four bolts 80 are inserted
from below the blocking plate 68 finally attached to engage with
the upper cylinder 38. In consequence, the first and second rotary
compression elements 32, 34 can be fixed to the rotary shaft
16.
[0034] Moreover, in this case, as the refrigerant, carbon dioxide
(CO.sub.2) described above which is a natural refrigerant
eco-friendly to global environments is used in consideration of
combustibility, toxicity and the like, and as a lubricant, an
existing oil is used such as a mineral oil, an alkyl benzene oil,
an ether oil, an ester oil or a polyalkyl glycol (PAG) oil.
[0035] Furthermore, on the side surface of the vessel main body 12A
of the sealed vessel 12, sleeves 140, 141 and 142, a refrigerant
discharge tube 96 and a service tube 97 are fixed by welding to
positions corresponding to those of the suction passages 58, 60 of
the upper support member 54 and the lower support member 56, the
discharge muffling chamber 64 and the upper part of the
electromotive element 14, respectively. The sleeve 140 is disposed
vertically adjacent to the sleeve 141, and the sleeve 142 is
substantially disposed along a diagonal line of the sleeve 141.
[0036] One end of a refrigerant introducing tube 92 for introducing
a refrigerant gas into the upper cylinder 38 is inserted into the
sleeve 140, and the one end of the refrigerant introducing tube 92
is connected to the suction passage 58 of the upper cylinder 38.
This refrigerant introducing tube 92 passes above the sealed vessel
12 to reach the sleeve 142, and the other end of the tube is
inserted into the sleeve 142 and connected to the intermediate
pressure discharge muffling chamber 64.
[0037] Moreover, one end of a refrigerant introducing tube 94 for
introducing the refrigerant gas into the lower cylinder 40 is
inserted into the sleeve 141, and the one end of this refrigerant
introducing tube is connected to the suction passage 60 of the
lower cylinder 40. The refrigerant discharge tube 96 is fixed to
the vessel main body 12A by welding, and one end of this
refrigerant discharge tube 96 is inserted into the sealed vessel
12.
[0038] Next, there will be described an operation of the rotary
compressor 10 constituted as described above. When a power is
supplied to the stator coil 28 of the electromotive element 14 via
the terminal 20 and a wiring line (not shown), the electromotive
element 14 is started to rotate the rotor 24. When this rotor
rotates, the first and second rollers 46, 48 fitted into the first
and second eccentric portions 42, 44 integrated with the rotary
shaft 16 eccentrically rotate in the upper and lower cylinders 38,
40.
[0039] In consequence, a refrigerant gas having a low pressure (a
first stage suction pressure is about 4 MPaG) is passed through the
refrigerant introducing tube 94 and the suction passage 60 formed
in the lower support member 56, sucked from the suction port 161
into the lower cylinder 40 on a low pressure chamber side, and
compressed by operations of the first roller 48 and a vane (not
shown) to obtain an intermediate pressure. The refrigerant gas
having the intermediate pressure is discharged from a high pressure
chamber side of the lower cylinder 40 into the intermediate
pressure discharge muffling chamber 64 formed in the lower support
member 56 via the discharge port (not shown).
[0040] Moreover, the intermediate pressure refrigerant gas
discharged into the intermediate pressure discharge muffling
chamber 64 passes through the refrigerant introducing tube 92
inserted into the intermediate pressure discharge muffling chamber
64, and is sucked from the suction port 160 into the upper cylinder
38 on a low pressure chamber side via the suction passage 58 formed
in the upper support member 54.
[0041] The sucked refrigerant gas having the intermediate pressure
is compressed in a second stage by operations of the roller 46 and
a vane (not shown) to constitute a refrigerant gas having a high
temperature and a high pressure (about 12 MPaG). Moreover, the
refrigerant gas having the high temperature and the high pressure
is discharged from the high pressure chamber side of the upper
cylinder 38 into the discharge muffling chamber 62 formed in the
upper support member 54 via a discharge port (not shown).
[0042] Furthermore, after the refrigerant discharged into the
discharge muffling chamber 62 is discharged from the communication
passage 65 disposed in the cover 63 into the sealed vessel 12, the
refrigerant passes through a gap formed in the electromotive
element 14 to move to the upper part of the sealed vessel 12, and
is discharged from the rotary compressor 10 through the refrigerant
discharge tube 96 connected to the upper part of the sealed vessel
12.
[0043] Since the rotation inertia article 82 is attached to the
rotor 24 in this manner, a necessary rotation inertia moment can be
obtained. In consequence, it is possible to obtain the having a
high efficiency in which a rotary vibration can be suppressed even
in a region where the compressor has the small number of rotations.
Since the rotation inertia article 82 is made of copper, the copper
alloy or the like, it is possible to obtain the rotation inertia
moment necessary for the decrease of the vibration with the
inexpensive material without enlarging the shape of the rotor 24
constituted of an expensive material.
Embodiment 2
[0044] Next, FIGS. 3, 4 show another embodiment of the present
invention, and FIG. 3 shows a vertically sectional view of a rotary
compressor in the present invention. FIG. 4 is an enlarged view
showing a positional relation between a rotation inertia article
and discharge ports 65 which discharge a gas to be discharged in
the present invention. It is to be noted that the same components
as those of the above embodiment are denoted with the same
reference numerals, and description thereof is omitted. As
described above in the first embodiment, in a rotary compressor 10,
a rotation inertia article 84 is formed into such an enlarged shape
as to cover the whole stator coil 28.
[0045] Moreover, as shown in FIG. 4, the discharge ports 65 which
discharge the gas from a rotary compression mechanism portion 18
into a sealed vessel 12 are disposed in positions corresponding to
1/2 or less of the maximum outer diameter of the rotation inertia
article 84.
[0046] Furthermore, an oil-containing refrigerant gas discharged
from the discharge ports 65 abuts on the rotation inertia article
84, and is separated into an oil and a refrigerant by a rotary
force of the rotation inertia article. The separated oil returns to
an oil reservoir of the compressor, and the separated gas passes
through a gap made between an outer periphery of an electromotive
element 14 and an inner periphery of the sealed vessel 12 to move
into the upper part of the sealed vessel 12. The gas is discharged
from the rotary compressor 10 through a refrigerant discharge tube
96 connected to the upper part of the sealed vessel 12.
[0047] Since the discharge ports 65 are disposed in the positions
corresponding to 1/2 or less of the maximum outer diameter of the
rotation inertia article 84, an oil separating capability obtained
by the rotation of the rotation inertia article can effectively be
used, an amount of the oil to be discharged can be decreased, and
the oil can stably be supplied.
[0048] It is to be noted that in the present embodiments, as the
rotary compressor, the high inner pressure type rotary compressor
10 has been described which includes the first and second rotary
compression elements 32, 34, but the present invention is not
limited to this rotary compressor, and may be applied to a rotary
compressor including a single cylinder or a rotary compressor
including three or more stage rotary compression elements. The
present invention is not limited to the high inner pressure type
rotary compressor 10, and may be applied to an intermediate inner
pressure type rotary compressor in which a refrigerant compressed
by a first rotary compression element is discharged into a sealed
vessel and then compressed by a second rotary compression
element.
[0049] Moreover, it is assumed in the embodiments that the second
rotary compression element 34 disposed on the side of the
electromotive element 14 is a second stage, the first rotary
compression element 32 disposed on the side opposite to the
electromotive element 14 is a first stage, and the refrigerant
compressed by the first rotary compression element 32 is compressed
by the second rotary compression element 34. However, the present
invention is not limited to the embodiments, and the refrigerant
compressed by the second rotary compression element may be
compressed by the first rotary compression element.
[0050] Furthermore, when a displacement volume of the first
compression mechanism is different from that of the second
compression mechanism in the multistage compressor, a weight
balance of the rotation inertia article 84 may be changed in
accordance with the displacement volume of each compression
mechanism to achieve the whole balance.
[0051] In addition, in the present embodiments, it has been
described that the rotary shaft is of a vertically disposed type,
but needless to say, the present invention may be applied to a
rotary compressor having a rotary shaft of a horizontally disposed
type. It has been described carbon dioxide is used as the
refrigerant of the rotary compressor, but another refrigerant may
be used.
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