U.S. patent application number 15/080328 was filed with the patent office on 2016-09-29 for rotary compressor.
The applicant listed for this patent is FUJITSU GENERAL LIMITED. Invention is credited to Yuji KOMAI, Naoya MOROZUMI.
Application Number | 20160281717 15/080328 |
Document ID | / |
Family ID | 55628952 |
Filed Date | 2016-09-29 |
United States Patent
Application |
20160281717 |
Kind Code |
A1 |
KOMAI; Yuji ; et
al. |
September 29, 2016 |
ROTARY COMPRESSOR
Abstract
A rotary compressor includes: a sealed vertical compressor
housing in which a refrigerant discharging unit is provided at an
upper part, a refrigerant intake unit is provided at a lower part,
and lubricant oil is retained; a compressing unit that is disposed
in the compressor housing, includes an upper end plate and a lower
end plate that block an annular cylinder and end portions of the
cylinder, and discharges a refrigerant sucked from the intake unit
through the discharging unit by compressing the refrigerant in the
cylinder; and a motor that is disposed in the compressor housing,
includes a cylindrical stator and a rotor that is fixed to a
rotation axis to rotate in the stator, and drives the compressing
unit via the rotation axis.
Inventors: |
KOMAI; Yuji; (Kanagawa,
JP) ; MOROZUMI; Naoya; (Kanagawa, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
FUJITSU GENERAL LIMITED |
Kawasaki-shi |
|
JP |
|
|
Family ID: |
55628952 |
Appl. No.: |
15/080328 |
Filed: |
March 24, 2016 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F04D 13/06 20130101;
F04D 7/00 20130101; F04C 2230/602 20130101; F04C 2230/231 20130101;
F04C 23/008 20130101; F04D 3/00 20130101; F04C 18/3564
20130101 |
International
Class: |
F04D 13/06 20060101
F04D013/06; F04D 3/00 20060101 F04D003/00; F04D 7/00 20060101
F04D007/00 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 27, 2015 |
JP |
2015-067242 |
Claims
1. A rotary compressor comprising: a sealed vertical compressor
housing in which a refrigerant discharging unit is provided at an
upper part, a refrigerant intake unit is provided at a lower part,
and lubricant oil is retained; a compressing unit that is disposed
in the compressor housing, includes an upper end plate and a lower
end plate that block an annular cylinder and end portions of the
cylinder, and discharges a refrigerant sucked from the intake unit
through the discharging unit by compressing the refrigerant in the
cylinder; and a motor that is disposed in the compressor housing,
includes a cylindrical stator and a rotor that is fixed to a
rotation axis to rotate in the stator, and drives the compressing
unit via the rotation axis, wherein, in a case where an inner
diameter of a body unit of the compressor housing is .phi.Dm, an
outer diameter of the upper end plate of the compressing unit is
.phi.Db, and an outer diameter of the stator of the motor is
.phi.Ds, .phi.Dm, .phi.Db, and .phi.Ds are set such that two
expressions of -0.05 mm.ltoreq..phi.Dm-.phi.Db.ltoreq.0.05 mm and
0.1 mm.ltoreq..phi.Dm-.phi.Ds.ltoreq.0.2 mm are satisfied, and an
outer circumferential portion of the upper end plate and an outer
circumferential portion of the stator are respectively spot-welded
to the body unit of the compressor housing at a plurality of sites
separated in a circumferential direction.
2. The rotary compressor according to claim 1, wherein the spot
welding between the stator of the motor and the body unit of the
compressor housing is performed after the spot welding between the
upper end plate of the compressing unit and the body unit.
3. The rotary compressor according to claim 2, wherein the spot
welding between the stator of the motor and the body unit of the
compressor housing is performed in a state where centering between
the stator and the rotor of the motor is performed.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is based upon and claims the benefit of
priority of the prior Japanese Patent Application No. 2015-067242,
filed on Mar. 27, 2015, the entire contents of which are
incorporated herein by reference.
FIELD
[0002] The present invention relates to a rotary compressor used in
an air conditioner or a refrigerating machine.
BACKGROUND
[0003] In the rotary compressor, if compressive strain is generated
in a stator of a motor disposed in a compressor housing,
magnetization characteristics of the stator are degraded to cause
an increase in iron loss, and thus the efficiency of the motor is
lowered.
[0004] For example, Japanese Laid-open Patent Publication No.
2010-255623 (Patent Document 1) discloses a compressor that
includes a sealed vessel, a motor including at least a stator and a
rotor and disposed in the sealed vessel, and a compression
mechanism including at least an axis driven by the rotor. In the
compressor, the outer diameter of the compression mechanism is
greater than the outer diameter of the stator, and the compressor
further includes a ring-shaped fixation member which is inserted
between the sealed vessel and the outer diameter of the stator to
be fixed to the outer circumference of the stator through an
interference fit, and is welded to the sealed vessel at three
locations.
[0005] In addition, Patent Document 1 discloses a compressor that
includes a sealed vessel, a motor including at least a stator and a
rotor and disposed in the sealed vessel, and a compression
mechanism including at least an axis driven by the rotor. In the
compressor, the outer diameter of the compression mechanism is
greater than the outer diameter of the stator, and the compressor
further includes a throttle part which is obtained by subjecting a
part of the sealed vessel to drawing processing and of which the
drawn part is in contact with the stator, the throttle part being
fixed to the stator by laser welding.
[0006] Furthermore, Japanese Laid-open Patent Publication No.
2008-248889 (Patent Document 2) discloses a compressor that
includes an annular stator, a rotor disposed in an internal space
of the stator to be rotatable, and a sealed vessel including a
cylindrical portion that accommodates the stator and the rotor, in
which the stator and the cylindrical portion are fixed to each
other at three or more locations in a circumferential direction by
spot welding, in a state where a clearance of 0.01 mm to 0.30 mm is
secured between an outer circumferential surface of the stator and
an inner circumferential surface of the cylindrical portion. The
compression mechanism of the compressor is screwed to a mounting
plate, and the mounting plate is spot-welded to the cylindrical
portion of the sealed vessel.
[0007] However, in the compressor disclosed in Patent Document 1
that includes a ring-shaped fixation member which is inserted
between the sealed vessel and the outer diameter of the stator to
be fixed to the outer circumference of the stator through an
interference fit, and is welded to the sealed vessel at three
locations, the ring-shaped fixation member is fixed to the outer
circumference of the stator through an interference fit. Therefore,
there is a problem in that compressive strain is generated in the
stator, and thus, the efficiency of the motor is lowered. In
addition, there is also a problem in that the costs for the use of
the fixation member are increased.
[0008] In addition, in the compressor disclosed in Patent Document
1 which includes a throttle part which is obtained by subjecting a
part of the sealed vessel to drawing processing and of which the
drawn part is in contact with the stator, and in which the throttle
part is fixed to the stator by laser welding, a part of the sealed
vessel is subjected to drawing processing. Therefore, there is a
problem in that the costs for the drawing processing are
increased.
[0009] Furthermore, in the compressor disclosed in Patent Document
2, the stator and the cylindrical portion are fixed to each other
at three or more locations in a circumferential direction by spot
welding, in a state where a radial clearance of 0.01 mm to 0.30 mm
is secured between the stator and the cylindrical portion, the
compression mechanism is screwed to a mounting plate, and the
mounting plate is spot-welded to the cylindrical portion of the
sealed vessel. Therefore, in a case where a radial clearance of
0.30 mm is provided between a stator and a cylindrical portion,
there is a problem in that since the radial clearance is too large,
it is necessary to perform centering of the stator with respect to
the cylindrical portion, and thus assembly work is increased. In
addition, since the compression mechanism is fixed to the
cylindrical portion via the mounting plate, there is a problem in
that costs for the use of the mounting plate are increased.
SUMMARY
[0010] According to an aspect of the embodiments, a rotary
compressor includes: a sealed vertical compressor housing in which
a refrigerant discharging unit is provided at an upper part, a
refrigerant intake unit is provided at a lower part, and lubricant
oil is retained; a compressing unit that is disposed in the
compressor housing, includes an upper end plate and a lower end
plate that block an annular cylinder and end portions of the
cylinder, and discharges a refrigerant sucked from the intake unit
through the discharging unit by compressing the refrigerant in the
cylinder; and a motor that is disposed in the compressor housing,
includes a cylindrical stator and a rotor that is fixed to a
rotation axis to rotate in the stator, and drives the compressing
unit via the rotation axis. In a case where an inner diameter of a
body unit of the compressor housing is .phi.Dm, an outer diameter
of the upper end plate of the compressing unit is .phi.Db, and an
outer diameter of the stator of the motor is .phi.Ds, .phi.Dm,
.phi.Db, and .phi.Ds are set such that two expressions of -0.05
mm.ltoreq..phi.Dm-.phi.Db.ltoreq.0.05 mm and 0.1
mm.ltoreq..phi.Dm-.phi.Ds.ltoreq.0.2 mm are satisfied, and an outer
circumferential portion of the upper end plate and an outer
circumferential portion of the stator are respectively spot-welded
to the body unit of the compressor housing at a plurality of sites
separated in a circumferential direction.
[0011] The object and advantages of the invention will be realized
and attained by means of the elements and combinations particularly
pointed out in the claims.
[0012] It is to be understood that both the foregoing general
description and the following detailed description are exemplary
and explanatory and are not restrictive of the invention.
BRIEF DESCRIPTION OF DRAWINGS
[0013] FIG. 1 is a vertical sectional view illustrating an example
of a rotary compressor according to the invention;
[0014] FIG. 2 is a cross-sectional view illustrating a first
compressing unit and a second compressing unit of the rotary
compressor of the example, when seen from above;
[0015] FIG. 3 is a vertical sectional view illustrating a stator
and a rotor of the rotary compressor of the example before being
assembled;
[0016] FIG. 4 is a vertical sectional view illustrating the stator
and the rotor of the rotary compressor of the example after being
assembled;
[0017] FIG. 5 is a vertical sectional view illustrating the
compressing unit and the stator of the rotary compressor and a body
unit of a compressor housing of the example before being fitted to
each other;
[0018] FIG. 6 is a vertical sectional view illustrating the
compressing unit and the stator of the rotary compressor and the
body unit of the compressor housing of the example after being
fitted to each other;
[0019] FIG. 7 is a cross-sectional view taken along line A-A of
FIG. 6; and
[0020] FIG. 8 is a cross-sectional view taken along line B-B of
FIG. 6.
DETAILED OF EMBODIMENTS
[0021] Hereinafter, an embodiment (example) of the invention will
be described in detail with reference to the drawings.
[0022] FIG. 1 is a vertical sectional view illustrating an example
of a rotary compressor according to the invention. FIG. 2 is a
cross-sectional view illustrating a first compressing unit and a
second compressing unit of the rotary compressor of the example,
when seen from above.
[0023] As illustrated in FIG. 1, a rotary compressor 1 includes a
compressing unit 12 that is disposed on a lower part of a
compressor housing 10 that is sealed and has a vertical cylindrical
shape, and a motor 11 that is disposed on an upper part of the
compressor housing 10 and drives the compressing unit 12 via a
rotation axis 15.
[0024] A stator 111 of the motor 11 is formed in a cylindrical
shape and is fixed to an inner circumferential surface of a body
unit 10A of the compressor housing 10 by spot welding. A
dimensional relationship and an assembly method of the body unit
10A of the compressor housing 10 and the stator 111 which are
characteristic configurations of the rotary compressor 1 of the
invention will be described below. A rotor 112 is disposed in the
cylindrical stator 111 and is fixed to the rotation axis 15 by
shrink-fitting which mechanically connects the motor 11 and the
compressing unit 12.
[0025] The compressing unit 12 includes a first compressing unit
12S and a second compressing unit 12T. As illustrated in FIG. 2,
the first compressing unit 12S includes an annular first cylinder
121S. The first cylinder 121S includes a first side-flared portion
122S that projects away from the annular outer circumference. A
first inlet hole 135S and a first vane groove 128S are radially
provided in the first side-flared portion 122S. In addition, the
second compressing unit 12T is disposed on the upper side of the
first compressing unit 12S. The second compressing unit 12T
includes an annular second cylinder 121T. The second cylinder 121T
includes a second side-flared portion 122T that projects away from
the annular outer circumference. A second inlet hole 135T and a
second vane groove 128T are radially provided in the second
side-flared portion 122T.
[0026] As illustrated in FIG. 2, a first cylinder inner wall 123S
having a circular shape is formed in the first cylinder 121S to be
concentric with the rotation axis 15 of the motor 11. A first
annular piston 125S having an outer diameter smaller than an inner
diameter of the first cylinder 121S is disposed in the first
cylinder inner wall 123S. A first cylinder chamber 130S that sucks,
compresses, and discharges a refrigerant is formed between the
first cylinder inner wall 123S and the first annular piston 125S. A
second cylinder inner wall 123T having a circular shape is formed
in the second cylinder 121T to be concentric with the rotation axis
15 of the motor 11. A second annular piston 125T having an outer
diameter smaller than an inner diameter of the second cylinder 121T
is disposed in the second cylinder inner wall 123T. A second
cylinder chamber 130T that sucks, compresses, and discharges a
refrigerant is formed between the second cylinder inner wall 123T
and the second annular piston 125T.
[0027] In the first cylinder 121S, the first vane groove 128S is
formed along the entire height of the cylinder in a radial
direction away from the first cylinder inner wall 123S. A flat
first vane 127S is slidably fitted in the first vane groove 128S.
In the second cylinder 121T, the second vane groove 128T is formed
along the entire height of the cylinder in the radial direction
away from the second cylinder inner wall 123T. A flat second vane
127T is slidably fitted in the second vane groove 128T.
[0028] As illustrated in FIG. 2, a first spring bore 124S is formed
on the outer side of the first vane groove 128S in the radial
direction so as to communicate with the first vane groove 128S from
an outer circumferential portion of the first side-flared portion
122S. A first vane spring 126S (refer to FIG. 1) that presses a
rear surface of the first vane 127S is inserted into the first
spring bore 124S. A second spring bore 124T is formed on the outer
side of the second vane groove 128T in the radial direction so as
to communicate with the second vane groove 128T from an outer
circumferential portion of the second side-flared portion 122T. A
second vane spring 126T (refer to FIG. 1) that presses a rear
surface of the second vane 127T is inserted into the second spring
bore 124T.
[0029] At the time of activating the rotary compressor 1, the first
vane 127S protrudes away from the first vane groove 128S into the
first cylinder chamber 130S due to the repulsive force of the first
vane spring 126S. A tip end of the first vane 1275 is in contact
with an outer circumferential surface of the first annular piston
125S, and by the first vane 127S, the first cylinder chamber 1305
is divided into a first inlet chamber 131S and a first compression
chamber 133S. Similarly, the second vane 127T protrudes away from
the second vane groove 128T into the second cylinder chamber 130T
due to the repulsive force of the second vane spring 126T. A tip
end of the second vane 127T is in contact with an outer
circumferential surface of the second annular piston 125T, and the
second cylinder chamber 130T is divided by the second vane 127T
into a second inlet chamber 131T and a second compression chamber
133T.
[0030] In addition, in the first cylinder 121S, a first pressure
guiding-in path 129S is formed which communicates with the outer
side of the first vane groove 128S in the radial direction and the
inside of the compressor housing 10 via an opening portion R (refer
to FIG. 1), introduces the compressed refrigerant in the compressor
housing 10, and applies back pressure to the first vane 127S by the
pressure of the refrigerant. The compressed refrigerant in the
compressor housing 10 is also introduced through the first spring
bore 124S. In addition, in the second cylinder 121T, a second
pressure guiding-in path 129T is formed which communicates with the
outer side of the second vane groove 128T in the radial direction
and the inside of the compressor housing 10 via the opening portion
R (refer to FIG. 1), introduces the compressed refrigerant in the
compressor housing 10, and applies back pressure to the second vane
127T by the pressure of the refrigerant. The compressed refrigerant
in the compressor housing 10 is also introduced through the second
spring bore 124T.
[0031] The first inlet hole 135S, that causes the first inlet
chamber 131S and an external unit to communicate with each other,
is provided in the first side-flared portion 122S of the first
cylinder 121S in order to suck the refrigerant from the external
unit into the first inlet chamber 131S. The second inlet hole 135T,
that causes the second inlet chamber 131T and the external unit to
communicate with each other, is provided in the second side-flared
portion 122T of the second cylinder 121T in order to suck the
refrigerant from the external unit into the second inlet chamber
131T. The cross sectional shapes of the first inlet hole 135S and
the second inlet hole 135T are circles.
[0032] As illustrated in FIG. 1, an intermediate partition plate
140 is disposed between the first cylinder 121S and the second
cylinder 121T and partitions the first cylinder chamber 130S (refer
to FIG. 2) of the first cylinder 121S from the second cylinder
chamber 130T (refer to FIG. 2) of the second cylinder 121T. In
addition, the intermediate partition plate 140 blocks an upper end
portion of the first cylinder 121S and a lower end portion of the
second cylinder 121T.
[0033] A lower end plate 160S is disposed on the lower end portion
of the first cylinder 121S and blocks the first cylinder chamber
130S of the first cylinder 121S. In addition, an upper end plate
160T is disposed on the upper end portion of the second cylinder
121T and blocks the second cylinder chamber 130T of the second
cylinder 121T. The lower end plate 160S blocks the lower end
portion of the first cylinder 121S and the upper end plate 160T
blocks the upper end portion of the second cylinder 121T.
[0034] A sub-bearing unit 161S is formed on the lower end plate
160S, and a sub-axis unit 151 of the rotation axis 15 is rotatably
supported by the sub-bearing unit 161S. A main-bearing unit 161T is
formed on the upper end plate 160T, and a main-axis unit 153 of the
rotation axis 15 is rotatably supported by the main-bearing unit
161T.
[0035] The rotation axis 15 includes a first eccentric portion 152S
and a second eccentric portion 152T which are eccentric to each
other by deviating the phases thereof by 180.degree.. The first
eccentric portion 152S is rotatably fitted in the first annular
piston 125S of the first compressing unit 12S. The second eccentric
portion 152T is rotatably fitted in the second annular piston 125T
of the second compressing unit 12T.
[0036] If the rotation axis 15 is rotated, the first annular piston
125S revolves along the first cylinder inner wall 123S in the first
cylinder 121S in a clockwise direction in FIG. 2. The first vane
127S is moved in a reciprocating manner by following the revolution
of the piston. According to the movement of the first annular
piston 125S and the first vane 127S, the volumes of the first inlet
chamber 131S and the first compression chamber 133S are
continuously changed, and thus the compressing unit 12 continuously
sucks, compresses, and discharges the refrigerant in sequence. If
the rotation axis 15 is rotated, the second annular piston 125T
revolves along the second cylinder inner wall 123T in the second
cylinder 121T in the clockwise direction in FIG. 2. The second vane
127T is moved in a reciprocating manner by following the revolution
of the piston. According to the movement of the second annular
piston 125T and the second vane 127T, the volumes of the second
inlet chamber 131T and the second compression chamber 133T are
continuously changed, and thus the compressing unit 12 continuously
sucks, compresses, and discharges the refrigerant in sequence.
[0037] As illustrated in FIG. 1, a cover for lower end plate 170S
is disposed on the lower side of the lower end plate 160S and a
lower muffler chamber 180S is formed between the cover for lower
end plate 170S and the lower end plate 1605. The first compressing
unit 12S is opened toward the lower muffler chamber 180S. That is,
a first outlet 190S (refer to FIG. 2) that communicates with the
first compression chamber 133S of the first cylinder 121S and the
lower muffler chamber 180S is provided on the lower end plate 160S
in the vicinity of the first vane 127S. A reed valve type first
discharge valve (not illustrated) that prevents backflow of the
compressed refrigerant is disposed in the first outlet 1905.
[0038] The lower muffler chamber 180S is one chamber formed in an
annular shape, and is a part of a communication path which causes
the discharging side of the first compressing unit 12S to
communicate with the inside of an upper muffler chamber 180T
through a refrigerant path 136 (refer to FIG. 2) that penetrates
the lower end plate 160S, the first cylinder 121S, the intermediate
partition plate 140, the second cylinder 121T, and the upper end
plate 160T. The lower muffler chamber 180S reduces the pressure
pulsation of the discharged refrigerant. A first discharge valve
cap (not illustrated) for restricting an opening amount of bent of
the first discharge valve is fixed together with the first
discharge valve by a rivet so as to overlap the first discharge
valve. The first outlet 190S, the first discharge valve, and the
first discharge valve cap configure a first discharge valve unit of
the lower end plate 160S.
[0039] As illustrated in FIG. 1, a cover for upper end plate 170T
is disposed on the upper side of the upper endplate 160T and the
upper muffler chamber 180T is formed between the cover for upper
end plate 170T and the upper end plate 160T. A second outlet 190T
(refer to FIG. 2), that communicates with the second compression
chamber 133T of the second cylinder 121T and the upper muffler
chamber 180T, is provided on the upper endplate 160T in the
vicinity of the second vane 127T. A reed valve type second
discharge valve (not illustrated), that prevents backflow of the
compressed refrigerant, is disposed in the second outlet 190T. A
second discharge valve cap (not illustrated) for restricting an
opening amount of bent of the second discharge valve is fixed
together with the second discharge valve by a rivet so as to
overlap the second discharge valve. The upper muffler chamber 180T
reduces the pressure pulsation of the discharged refrigerant. The
second outlet 190T, the second discharge valve, and the second
discharge valve cap configure a second discharge valve unit of the
upper end plate 160T.
[0040] The cover for lower end plate 170S, the lower end plate
160S, the first cylinder 121S, and the intermediate partition plate
140 are inserted from the lower side and are fastened to the second
cylinder 121T by using a plurality of penetrating bolts 175 that
are screwed into female screws provided on the second cylinder
121T. The cover for upper end plate 170T and the upper end plate
160T are inserted from the upper side and are fastened to the
second cylinder 121T by using a penetrating bolt 174 that is
screwed into the female screw provided on the second cylinder 121T.
The cover for lower end plate 170S, the lower endplate 160S, the
first cylinder 121S, the intermediate partition plate 140, the
second cylinder 121T, the upper end plate 160T, and the cover for
upper end plate 170T, which are integrally fastened by using the
plurality of penetrating bolts 174 and 175 and the like, configure
the compressing unit 12. In the compressing unit 12, the outer
circumferential portion of the upper end plate 160T is fixed to the
body unit 10A of the compressor housing 10 by spot welding, and
thus the compressing unit 12 is fixed to the compressor housing 10.
The dimensional relationship of the upper end plate 160T and the
body unit 10A will be described below.
[0041] The low pressure refrigerant of a refrigerant circuit is
guided to the first compressing unit 12S through an accumulator
(not illustrated) and the first inlet hole 135S (refer to FIG. 2)
of the first cylinder 121S. In addition, the low pressure
refrigerant of the refrigerant circuit is guided to the second
compressing unit 12T through the accumulator (not illustrated) and
the second inlet hole 135T (refer to FIG. 2) of the second cylinder
121T. That is, the first inlet hole 135S and the second inlet hole
135T are connected to an evaporator of the refrigerant circuit in
parallel.
[0042] A discharge pipe 107 as a discharging unit that is connected
to the refrigerant circuit and discharges the high pressure
refrigerant to a condenser side of the refrigerant circuit is
connected to the top of the compressor housing 10. That is, the
first outlet 190S and the second outlet 190T are connected to the
condenser of the refrigerant circuit.
[0043] In the compressor housing 10, the lubricant oil is enclosed
approximately up to the height of the second cylinder 121T. In
addition, the lubricant oil is sucked through a lubricating pipe
16, which is attached to the lower end portion of the rotation axis
15, by a pump impeller (not illustrated) inserted into a lower
portion of the rotation axis 15, and circulates in the compressing
unit 12, thereby performing lubrication between sliding components
(the first annular piston 125S and the second annular piston 125T)
and performing sealing of a minute gap of the compressing unit
12.
[0044] Next, the characteristic configuration of the rotary
compressor 1 of the example will be described with reference to
FIGS. 3 to 8. FIG. 3 is a vertical sectional view illustrating a
stator and a rotor of the rotary compressor of the example before
being assembled. FIG. 4 is a vertical sectional view illustrating
the stator and the rotor of the rotary compressor of the example
after being assembled. FIG. 5 is a vertical sectional view
illustrating the compressing unit and the stator of the rotary
compressor and a body unit of a compressor housing of the example
before being fitted to each other. FIG. 6 is a vertical sectional
view illustrating the compressing unit and the stator of the rotary
compressor and the body unit of the compressor housing of the
example after being fitted to each other. FIG. 7 is a
cross-sectional view taken along line A-A of FIG. 6. FIG. 8 is a
cross-sectional view taken along line B-B of FIG. 6.
[0045] As illustrated in FIG. 3, the outer diameter .phi.Dr of the
rotor 112 of the motor 11 is formed to be smaller than the inner
diameter .phi.Dt of the stator 111 by 1.4 mm and the clearance
between the outer circumferential surface of the rotor 112 and the
inner circumferential surface of the stator 111 is 0.7 mm. The
thickness of a shim 201 of a gap gage 200 which performs centering
between the rotor 112 and the stator 111, is 0.6 mm, that is,
smaller by 0.1 mm than the 0.7 mm of clearance between the outer
circumferential surface of the rotor 112 and the inner
circumferential surface of the stator 111.
[0046] As illustrated in FIG. 5, the outer diameter .phi.Ds of the
stator 111 of the motor 11 is formed to be smaller than the outer
diameter .phi.Db of the upper end plate 160T of the compressing
unit 12 (.phi.Ds<.phi.Db). In addition, the inner diameter
.phi.Dm of the body unit 10A of the compressor housing 10 is formed
to be greater than the outer diameter .phi.Ds of the stator 111 by
0.1 mm to 0.2 mm (0.1 mm.ltoreq..phi.Dm-.phi.Ds.ltoreq.0.2 mm).
Furthermore, the inner diameter .phi.Dm of the body unit 10A is
formed in a range of -0.05 mm to +0.05 mm relative to the outer
diameter .phi.Db of the upper end plate 160T (-0.05
mm.ltoreq..phi.Dm-.phi.Db .ltoreq.0.05 mm). As illustrated in FIGS.
7 and 8, the body unit 10A is formed in a cylindrical shape
obtained by rolling a steel sheet and welding the end portions of
the sheet by butt welding, and the accuracy of the dimension of the
inner diameter .phi.Dm and the roundness are lower than those in a
case where the body unit is formed by deep drawing or machining (a
butt-welded site 165 is illustrated in FIGS. 7 and 8).
[0047] Next, a method of fixing the motor 11 and the compressing
unit 12 that are connected to each other via the rotation axis 15,
in the body unit 10A of the compressor housing 10 will be
described. As illustrated in FIGS. 3 and 4, at the time of
assembling the motor 11, the stator 111 is placed on the upper end
portion of a cylindrical assembly jig 210 including a circular
concave portion 211 at the bottom thereof. The gap gage 200 of
which a plurality of the shims 201 are attached to the outer
circumferential portion is set to the upper portion of the stator
111.
[0048] The compressing unit 12 in which the rotor 112 is fixed to
the rotation axis 15 is lowered by placing the rotor 112 downward
so that the end portion of the rotation axis 15 comes into contact
with an upper convex portion 202 of the gap gage 200. If the
compressing unit 12 is further lowered, the rotor 112 is guided to
the shim 201 of the gap gage 200 and is inserted into the stator
111 so that the gap gage 200 is pushed downward. As illustrated in
FIG. 4, if a lower convex portion 203 of the gap gage 200 is fitted
into the concave portion 211 of the assembly jig 210, the rotor 112
is completely inserted into the stator 111 and is centered by the
shims 201, and thus the motor 11 is assembled.
[0049] Next, as illustrated in FIGS. 5 and 6, in a state where the
motor 11 and the compressing unit 12 are placed on the assembly jig
210, the upper end plate 160T of the compressing unit 12 and the
stator 111 of the motor 11 are fitted into the body unit 10A of the
compressor housing 10. Since the inner diameter .phi.Dm of the body
unit 10A is in a range of -0.05 mm to +0.05 mm relative to the
outer diameter .phi.Db of the upper end plate 160T, the fitting
between the body unit 10A and the upper end plate 160T is light
press-fitting or light shrink-fitting in comparison with general
press-fitting or shrink-fitting. Since the inner diameter .phi.Dm
of the body unit 10A is formed to be greater than the outer
diameter .phi.Ds of the stator 111 by 0.1 mm to 0.2 mm, the fitting
between the body unit 10A and the stator 111 can be performed in a
non-contact manner or in a single-sided contact manner in which
compressive force is not applied. As illustrated in FIG. 6, the
body unit 10A is lowered until the lower end thereof comes into
contact with a step portion 212 of the assembly jig 210, and thus
the fitting work is ended. In this state, a clearance of 0.05 mm to
0.10 mm is formed between the inner circumferential portion of the
body unit 10A and the outer circumferential portion of the stator
111, and the centering between the stator 111 and the rotor 112 is
performed.
[0050] Next, a method of fixing the upper end plate 160T of the
compressing unit 12 and the stator 111 of the motor 11 to the body
unit 10A of the compressor housing 10 will be described with
reference to FIGS. 6 to 8. In the body unit 10A, three holes 164
are provided (three or more holes 164 may be provided) at an
interval of 120.degree. in a circumferential direction respectively
at a position where the upper endplate 160T is fitted, a position
of the stator 111 on the compressing unit 12 side, and a position
of the stator 111 symmetrical to the position on the compressing
unit 12 side. Welding wire is inserted into the holes 164 and the
body unit 10A and the upper end plate 160T are firstly welded by
spot welding. Next, the body unit 10A and the stator 111 are welded
at the position of the stator 111 on the compressing unit 12 side
and the position of the stator 111 symmetrical to the position on
the compressing unit 12 side. The welding at the position on the
compressing unit 12 side, and the welding at the position
symmetrical to the position on the compressing unit 12 side, may be
performed in an arbitrary order. Spot-welded sites 163 are
illustrated in FIG. 6 (the holes 164 are completely blocked by spot
welding and stand the pressure of the compressed refrigerant).
Thereafter, the gap gage 200 is detached.
[0051] The motor 11 which is centered by the compressing unit 12
and the gap gage 200 is positioned in the body unit 10A to be fixed
by firstly welding the body unit 10A and the upper end plate 160T.
The stator 111 is directly welded to the body unit 10A in a state
of being centered and in a state of not receiving compressive force
in the radial direction from the body unit 10A. Therefore, the
compressive strain is not generated in the stator 111, and thus the
magnetization characteristics of the stator are not degraded so
that iron loss is not increased. As a result, the efficiency of the
motor 11 is high and it is possible to suppress an increase in
costs.
[0052] In addition, the stator 111 is fixed to the body unit 10A by
spot welding at the position of the stator 111 on the compressing
unit 12 side and the position of the stator 111 symmetrical to the
position on the compressing unit 12 side. Therefore, even if the
rotary compressor 1 receives impact such as falling, the stator 111
is not damaged due to the dislocation of the caulking, which is
between the welding position on the compressing unit 12 side and
the position symmetrical to the welding position on the compressing
unit 12 side, of the stator 111 that is formed by caulking the
stacked steel sheets. Furthermore, as illustrated in FIG. 8, if the
circumferential directional positions of the spot-welded sites 163
of the upper end plate 160T, the circumferential directional
positions of the spot-welded sites 163 of the stator 111 on the
compressing unit 12 side, and the circumferential directional
positions of the spot-welded sites 163 of the stator 111 which are
the positions symmetrical to the circumferential directional
positions on the compressing unit 12 side are disposed such that
the phases thereof are shifted from each other in the
circumferential direction, the welded sites are not aligned in a
straight line in an axial direction. Therefore, the distance
between the welded sites of which the strength is relatively weak
becomes great, and thus the strength of the body unit 10A does not
become weak. In addition, since the maximum clearance between the
inner circumferential portion of the body unit 10A and the outer
circumferential portion of the stator 111 is 0.10 mm, a spatter due
to welding does not enter the compressor housing 10.
[0053] After the compressing unit 12 and the motor 11 are welded to
be fixed to the body unit 10A, if a bottom 100 and a top 10B are
welded to the body unit 10A by full circle welding as illustrated
in FIG. 1, the assembly of the rotary compressor 1 is completed.
The invention can be applied to a single cylinder type rotary
compressor and a two-stage compression type rotary compressor.
[0054] Hereinbefore, the example has been described, but the
example is not limited by the contents described above. In
addition, the components described above include those that can be
easily conceived by those skilled in the art, those that are
substantially identical thereto, and those in a scope of so-called
equivalents. In addition, the components described above can be
appropriately combined. Furthermore, at least one of various
omission, replacement, and modification of the components can be
performed without departing from the gist of the example.
[0055] According to an aspect of the embodiments, in a case where
the inner diameter of the body unit of the compressor housing is
.phi.Dm, the outer diameter of the upper end plate of the
compressing unit is .phi.Db, and the outer diameter of the stator
of the motor is .phi.Ds, .phi.Dm, .phi.Db, and .phi.Ds are set such
that two expressions of -0.05 mm.ltoreq..phi.Dm-.phi.Db.ltoreq.0.05
mm and 0.1 mm .ltoreq..phi.Dm-.phi.Ds.ltoreq.0.2 mm are satisfied,
and the outer circumferential portion of the upper end plate and
the outer circumferential portion of the stator are respectively
spot-welded to the body unit of the compressor housing at a
plurality of sites separated in the circumferential direction.
Therefore, the compressive strain is not generated in the stator of
the motor disposed in the compressor housing, and thus the
magnetization characteristics of the stator are not degraded. As a
result, the efficiency of the motor is high and it is possible to
suppress an increase in costs.
[0056] All examples and conditional language recited herein are
intended for pedagogical purposes of aiding the reader in
understanding the invention and the concepts contributed by the
inventors to further the art, and are not to be construed as
limitations to such specifically recited examples and conditions,
nor does the organization of such examples in the specification
relate to a showing of the superiority and inferiority of the
invention. Although the embodiments of the present invention have
been described in detail, it should be understood that the various
changes, substitutions, and alterations could be made hereto
without departing from the spirit and scope of the invention.
* * * * *