Information
-
Patent Grant
-
6227827
-
Patent Number
6,227,827
-
Date Filed
Monday, June 28, 199925 years ago
-
Date Issued
Tuesday, May 8, 200123 years ago
-
Inventors
-
Original Assignees
-
Examiners
Agents
-
CPC
-
US Classifications
Field of Search
-
International Classifications
-
Abstract
A scroll compressor which can be easily sealed and assembled is presented. Also a scroll compressor which can be sealed easily and at low cost is presented. It includes a cylindrical front casing with a bottom, a rear cover to be fitted to the inner circumference of the front casing, a fixed scroll having an end plate to be fitted to the inner circumference, a fitting portion to be fitted concentrically to the rear cover, and a spiral blade disposed at the opposite side of the fitting portion, a movable scroll engaged with the fixed scroll and swiveling at a specified radius of swivel, and a rotation preventive mechanism for preventing rotation of the movable scroll and permitting swivel motion only. By assembling the fixed scroll and rear cover, a nearly triangular recess is formed in the butt junction of the end plate and rear cover, a seal member is fitted into the recess, and the fixed scroll and rear cover fitting the seal member are assembled into the front casing, thereby sealing both between the suction pressure and discharge pressure, and between the atmospheric pressure and discharge pressure.
Description
FIELD OF THE INVENTION
The present invention relates to a scroll compressor, and more particularly to a scroll compressor of an air conditioner used in automobile or the like.
BACKGROUND OF THE INVENTION
A conventional scroll compressor comprises, as shown in
FIG. 6
, a rear casing
32
having an opening at the front side, and a front cover
31
placed in its opening. A movable scroll
34
, a fixed scroll
39
, and a rotation preventive mechanism
36
are disposed in the rear casing,
32
. An outer circumference of the fixed scroll
39
contacts with an inner circumference of the rear casing
32
. The movable scroll
34
is placed between the front cover
31
and the fixed scroll
39
in order to swivel while contacting with the surface of the fixed scroll
39
. The rotation preventive mechanism
36
is placed between the movable scroll
34
and the front cover
31
in order to allow the swivel motion only while preventing rotation of the movable scroll
34
. A suction chamber
46
for sucking a refrigerant and a discharge chamber
47
for discharging the refrigerant are mutually partitioned through the fixed scroll
39
. A suction port
32
c
for sucking the refrigerant is formed in an outer wall of the rear casing
32
of the suction chamber
46
. A discharge port
32
d
for discharging the refrigerant is formed in the outer wall of the rear casing
32
of the discharge chamber
47
. A first seal member
41
having an O-ring
41
is placed between the inner circumference
32
a
of the rear casing
32
and the fixed scroll
39
. This first seal member
41
seals between the fixed scroll
39
and the rear casing
32
. It is thus completely sealed between the suction chamber
46
and discharge chamber
47
. A plurality of mounting bases
32
b
for mounting on a vehicle or other mechanical structure are integrally disposed on the outer wall of the rear casing
32
. The front cover
31
has a clutch mounting section
31
c
. A shaft
40
is installed so as to cooperate with the movable scroll
34
, and this shaft
40
penetrates through the clutch mounting section
31
c
, and has its leading end exposed outside. An electromagnetic clutch
38
is installed outside of the clutch mounting section
31
c
, and is coupled to the shaft
10
. The front cover
31
is coupled to the rear casing
32
through a second seal member
45
, by using bolt
44
or other bonding member. The second seal member
45
seals between the front cover
31
and rear casing
32
, and by this seal member
45
, the suction chamber
46
and the outside are completely isolated.
Thus, a pressure vessel sealing mutually between the suction pressure and atmospheric pressure was constituted by using the first seal member
41
and second seal member
45
.
Such conventional compressor, however, required two seal members, that is, the first seal member
41
for sealing between the suction chamber
46
and the discharge chamber
47
, and the second seal member
45
for sealing between the suction chamber
46
and the outside, and the compressor assembling process was complicated, and the manufacturing cost was high.
It is an object of the invention to present a scroll compressor that is easier to assemble and is lower in manufacturing cost.
SUMMARY OF THE INVENTION
The sealing method of the scroll compressor of the invention is a sealing method of a scroll compressor which comprises:
(a) a cylindrical front casing having a bottom, an opening, and an inner circumference,
(b) a rear cover fitted to the inner circumference to cover the opening,
(c) a fixed scroll having an end plate fitted to the inner circumference, a fitting portion fitted concentrically to the rear cover, and a spiral blade,
(d) a movable scroll engaged with the fixed scroll to swivel in a specified radius of swivel, and
(e) a rotation preventive mechanism for preventing rotation of the movable scroll to permit swivel motion only.
The sealing method is characterized by forming a recess in the butt junction of the end plate and the rear cover by assembling the fixed scroll and the rear cover, fitting a seal member to the recess, and assembling the fixed scroll and rear cover fitting the seal member into the front casing, and sealing both between the suction pressure and discharge pressure, and between the discharge pressure and atmospheric pressure.
A scroll compressor for compressing refrigerant of the invention comprises:
(a) a front casing having an inner circumference, a bottom and an opening,
(b) a fixed scroll disposed in the front casing,
(c) a movable scroll disposed between the bottom and the fixed scroll,
(d) a rear cover disposed to cover the opening,
(e) a suction chamber surrounded by the inner circumference, fixed scroll, and rear cover,
(f) a discharge chamber surrounded by the inner circumference, fixed scroll, and rear cover, and
(g) a seal member.
The fixed scroll has a first fitting portion and a first outer circumference fitted to the inner circumference, the rear cover has a second fitting portion, and a second outer circumference fitted to the inner circumference, the first fitting portion and the second fitting portion form a mutually joined butt junction, the seal member is disposed at the butt junction so as to contact with the first fitting portion, second fitting portion and the inner circumference, and the seal member seals between the suction chamber and the discharge chamber, and between the outside of the rear cover and the discharge chamber.
Preferably, the butt junction forms a recess surrounded by the first outer circumference, second outer circumference, and inner circumference, and the seal member is disposed in the recess.
Preferably, the recess has a nearly triangular shape.
In this constitution, the pressure in the suction chamber composed of the front casing and fixed scroll, the pressure in the discharge chamber composed of the fixed scroll and rear cover, and the atmospheric pressure are partitioned by one seal member disposed in the recess, so that the scroll compressor can be easily sealed and assembled.
Moreover, by using one seal member only, the scroll compressor can be sealed, so that the manufacturing cost may be saved.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1
is a sectional view of a scroll compressor in a first embodiment of the invention.
FIG.
2
(
a
) is a sectional view of a rear cover alone shown in
FIG. 1
, and FIG.
2
(
b
) is a sectional view of a fixed scroll alone.
FIG.
3
(
a
) and FIG.
3
(
b
) are magnified sectional views showing a recess in a nearly triangular shape.
FIG.
4
(
a
) to FIG.
4
(
d
) are sectional views showing modified examples of the recess.
FIG. 5
is a sectional view showing a modified example of the seal member.
FIG. 6
is a sectional view of a conventional scroll compressor.
Reference Numerals
Front casing
1
a
Inner circumference (fitting surface)
1
b
Base
1
c
Bottom
2
Crankshaft
3
a
,
3
b
Bearing
4
Movable scroll
5
a
,
5
b
Balancer
6
Oldham's ring (rotation preventive mechanism)
7
Slot plate
8
Electromagnetic clutch
9
Fixed scroll
9
a
End plate
9
b
Outer circumference
9
c
Blade
9
d
First fitting portion
9
e
First chamfering portion
9
f
Reference hole
10
Rear cover
10
a
Cylindrical portion
10
b
Cover portion
10
d
Second fitting portion
10
e
Second chamfering portion
11
O-ring (seal member)
12
Discharge hole
14
Valve retainer
15
Discharge chamber
16
Discharge port
17
Coupling hole
18
Butt junction
21
Recess
25
Suction chamber
DETAILED DESCRIPTION OF THE INVENTION
The compressor of the invention comprises a cylindrical front casing with a bottom and a rear cover fitted to the inner circumference of the front casing. The front casing incorporates an end plate, a fixed scroll, a movable scroll, and a drive mechanism. The end plate is fitted to the inner circumference of the front casing. The fixed scroll has a fitting portion to be fitted concentrically to the rear cover, and a spiral blade formed at the opposite side of this fitting portion. The movable scroll is engaged with the fixed scroll, and swivels at a specified radius of swivel. The drive mechanism includes a rotation preventive mechanism which permits only swivel motion of the movable scroll and prevents its rotation. A pressure vessel is composed by assembling the rear cover fitted and coupled to the fixed scroll into the front casing incorporating the movable scroll and drive mechanism. By assembling the fixed scroll and rear cover, one nearly triangular recess is formed at the butt junction of the end plate and rear cover. A seal member is fitted into this recess, and they are assembled into the front casing, which seals both between the suction pressure and discharge pressure, and between atmospheric pressure and discharge pressure.
In this constitution, one seal member seals the suction pressure, discharge pressure, and atmospheric pressure mutually. As a result, an easily sealed scroll compressor is obtained. The manufacturing cost. is saved. Moreover, the compressor can be installed easily at correct position at high precision.
Referring now to the drawings, an embodiment of the invention is described below.
FIG.1
is a longitudinal sectional view showing an assembled state of a scroll compressor. In
FIG. 1
, the scroll compressor comprises a front casing
1
, a rear cover
10
, a fixed scroll
9
, a movable scroll
4
, a rotation preventive mechanism
6
, and a seal member
11
. The front casing
1
has a cylindrical shape forming a bottom
1
c
. A crankshaft
2
, balancers
5
a
,
5
b
, an Oldham's ring
6
as rotation preventive mechanism, and a slot plate
7
are installed in the bottom
1
c
of the front casing
1
. The crankshaft
2
is supported by bearings
3
a
,
3
b
. The movable scroll
4
is driven by the crankshaft
2
. The balancers
5
a
,
5
b
serve to cancel the imbalance of the movable scroll
4
. The rotation preventive mechanism
6
prevents rotation of the movable scroll
4
, and permits only swivel motion. The slot plate
7
holds the Oldham's ring
6
.
An electromagnetic clutch
8
is fitted to the leading end of the crankshaft
2
. The electromagnetic clutch
8
transmits rotation of the engine or automobile or other machine to the crankshaft
2
, and turns on and of f the operation of the compressor.
The front casing
1
has an inner circumference
1
a
has the fitting surface to be fitted to the fixed scroll
9
and rear cover
10
, and an O-ring
11
as the seal member is disposed to abut against the fitting surface
1
a
. The O-ring
11
as the seal member is not particularly limited, and a deformable elastic material is used as the seal member, such as synthetic rubber, natural rubber, plastic material, and inorganic material.
The front casing
1
has a base
1
b
formed at the side wall. The base
1
b
is fitted to an external device such as an automobile. That is, both the bottom
1
c
for holding the crankshaft
2
and the base
1
b
for fixing to the external device are formed in the front casing
1
. Accordingly, the base
1
b
and electromagnetic clutch
8
are easily installed in the external device and coupled at correct position at high precision.
FIG.
2
(
b
) is a sectional view of the fixed scroll
9
alone in the embodiment. The fixed scroll
9
has an end plate
9
a
and a spiral blade
9
c
. The end plate
9
a
is fitted to the outer circumference
9
b
of the fitting surface
1
a
of the front casing
1
. The blade
9
c
is disposed upright on the end plate
9
a
. The blade
9
c
is disposed to be engaged with the movable scroll. The end plate
9
a
has a first fitting portion
9
d
and a first chamfering portion
9
e
formed at the opposite side of the blade
9
c
.
The first chamfering portion
9
e
is formed at the edge of the outer circumference
9
b
adjacently to the first fitting portion
9
d
. The first fitting portion
9
d
is fitted and coupled concentrically to the rear cover
10
. An assembly reference hole
9
f
is formed at the blade
9
c
side, and this assembly reference hole
9
f
is used as the reference when assembling the fixed roll
9
.
A discharge hole
12
is formed nearly in the center of the end plate
9
a
. To cover the discharge hole
12
, a discharge valve
13
and a valve retainer
14
are installed. The discharge valve
13
and valve retainer
14
open or close the discharge hole
12
. The front casing
1
and fixed scroll
9
form a suction chamber
25
. The rear cover
10
and fixed scroll
9
form a discharge chamber
15
. A suction port (not shown) is formed in the wall of the front casing
1
of the suction chamber
25
. A discharge port
16
is formed in the rear cover
10
of the discharge chamber
15
.
A refrigerant is sucked into the suction chamber
25
from the suction port, and the refrigerant in the suction chamber
25
is compressed by the fixed scroll and movable scroll
4
. The compressed refrigerant is discharged into the discharge chamber
15
through the discharge hole
12
.
FIG.
2
(
a
) is a sectional view of the rear cover
10
alone of the embodiment. The rear cover
10
has a cover portion
10
b
, and a cylindrical portion
10
a
disposed upright on the cover portion
10
b
. The cover portion
10
b
has a discharge port
16
, a coupling hole
17
, and a fixing hole (not shown).
The refrigerant flows from the discharge chamber
15
through the discharge port
16
, and is discharged into the air conditioner cycle. The coupling hole
17
couples the fixed scroll
9
to the rear cover
10
. The fixing hole fixes the rear cover
10
to the front casing
1
. After the fixed scroll
9
is fitted into the front casing
1
, in order to seal within the front casing
1
, the fixed scroll
9
is fitted by means of screw or other fixing means (not shown).
The cylindrical portion
10
a
has a second fitting portion
10
d
formed at the end, and a second chamfering portion
10
e
formed at the outer edge of the end. The second fitting portion
10
d
is fitted to the first fitting portion
9
d
of the end plate
9
a
.
The fixed scroll
9
and the rear cover
10
are concentrically coupled by screw or other means through engagement of the first fitting portion
9
d
and second fitting portion
10
d
. When the fixed scroll
9
and the rear cover
10
are mutually coupled, at the butt junction
18
of the end plate
9
a
and the end of the cylindrical portion
10
a
, the first chamfering portion
9
e
and second chamfering portion
10
e
form a nearly triangular recess. The O-ring
11
is fitted into the recess. With the O-ring
11
fitted into the recess, the fixed scroll
9
and rear cover
10
are assembled into the front casing
1
. In this state, the space in the nearly triangular recess is formed by the fitting surface
1
a
, first chamfering portion
9
e
, and second chamfering portion
10
e
.
FIG. 3
is an essential magnified sectional view showing an assembled state of O-ring
11
in the recess space formed by the fitting surface.
1
a
, first chamfering portion
9
e
, and second chamfering portion
10
e
. As shown in FIG.
3
(
a
), an O-ring is fitted into a recess
21
formed by the first chamfering portion
9
e
and second chamfering portion
10
e
. Next, as shown in FIG.
3
(
b
), the fixed scroll
9
having the O-ring fitted into the recess
21
and the rear cover
10
are assembled into the front casing
1
.
The O-ring
11
assembled in the front casing
1
abuts against the fitting surface la of the front casing
1
, and also abuts against the fitting surface
1
a
with the first chamfering portion
9
e
and the second chamfering portion
10
e
. Thus, the O-ring
11
is sealed, in the recess
21
, as being pressed against the fitting surface la with the first chamfering portion
9
e
and second chamfering portion
10
e
.
In this constitution, the compressor outside, suction chamber
25
, and discharge chamber
15
are mutually sealed. That is, between the O-ring
11
and the fitting surface
1
a
, the suction pressure and atmospheric pressure are sealed, and between the first chamfering portion
9
e
and the O-ring
11
, the suction pressure and discharge pressure are sealed, and further between the second chamfering portion
10
e
and the O-ring
11
, the discharge pressure and atmospheric pressure are sealed.
In this constitution, the refrigerant enters the suction chamber
25
through the suction port formed in the suction chamber.
25
, and enters the discharge chamber
15
through the discharge hole
12
, and gets into the refrigeration cycle through the discharge port
16
.
In this embodiment, the following modifications are also possible.
As shown in FIG.
4
(
a
) or FIG.
4
(
b
), only one of the fixed scroll
9
and rear cover
10
has a chamfering portion (
9
e
or
10
e
) at the butt junction
18
, and the recess
21
is formed as being surrounded by its chamfering portion and inner circumference
1
a
.
As shown in FIG.
4
(
c
) or FIG.
4
(
d
), only one of the fixed scroll
9
and rear cover
10
has a recess at the butt junction
18
, and this recess is formed as being surrounded by the fixed scroll
9
, rear cover
10
, and inner circumference
1
a
.
The compressor thus constituted as shown in
FIG. 4
has an excellent sealing characteristic. However, its effect is slightly smaller than in the above embodiment.
As shown in
FIG. 5
, the seal member
11
is an O-ring having a nearly T-shape section, and this T-shaped O-ring contacts with the fixed scroll
9
, rear cover
10
, and inner circumference
1
a
.
The compressor thus constituted as shown in
FIG. 5
has an excellent sealing characteristic. However, its effect is slightly-smaller than in the constitution in Fig.
4
.
The discharge port
16
is formed in the front casing.
Even in this modified example, the same effect as in the embodiment is obtained.
As described herein, according to the constitution of the invention, the pressure in the suction chamber composed of the front casing and fixed scroll, the pressure in the discharge chamber composed of the fixed scroll and rear cover, and the atmospheric pressure can be partitioned by one seal member, so that the scroll compressor can be easily sealed and assembled. Moreover, by using one seal member only, the scroll compressor can be sealed, so that the manufacturing cost is saved.
In particular, excellent effects are obtained in the constitution of forming a nearly triangular recess at the butt junction of the fixed scroll and rear cover.
Further, when the compressor of the invention is installed in the machine, the compressor can be mounted easily at correct position at high precision.
Claims
- 1. A sealing method of a scroll compressor, said scroll compressor comprising:(a) a cylindrical front casing having a bottom, an opening, and an inner circumference, (b) a rear cover fitted to said inner circumference to cover said opening, (c) a fixed scroll having an end plate fitted to said inner circumference, a fitting portion fitted concentrically to said rear cover, and a spiral blade, (d) a movable scroll engaged with said fixed scroll to swivel in a specified radius of swivel, and (e) a rotation preventive mechanism for preventing rotation of said movable scroll to permit swivel motion only, said sealing method comprising: forming a first chamfering portion at a first outer circumference of said fixed scroll, forming a second chamfering portion at a second outer circumference of said rear cover, forming a recess in a butt junction of said fixed scroll and said rear cover by assembling said first chamfering portion of said fixed scroll and said second chamfering portion of said rear cover, fitting a seal member to said recess, and assembling said fixed scroll and rear cover fitting said seal member into said front casing, thereby creating a seal between a suction pressure and discharge pressure, and a seal between the discharge pressure and atmospheric pressure.
- 2. A sealing method of claim 1,wherein said recess has a nearly triangular shape.
- 3. A sealing method of claim 1,wherein said scroll compressor further comprises a shaft coupled to said movable scroll in said front casing and exposed to outside from said bottom, and an electromagnetic clutch coupled to said shaft at said outside.
- 4. A scroll compressor for compressing a refrigerant comprising:(a) a front casing having an inner circumference, a bottom and an opening, (b) a fixed scroll disposed in said front casing, (c) a movable scroll disposed between said bottom and said fixed scroll, (d) a rear cover disposed to cover said opening, (e) a suction chamber surrounded by said inner circumference, fixed scroll, and rear cover, (f) a discharge chamber surrounded by said inner circumference, fixed scroll, and rear cover, and (g) a seal member, wherein said fixed scroll has a first fitting portion and a first outer circumference fitted to said inner circumference, said rear cover has a second fitting portion, and a second outer circumference fitted to said inner circumference, said first fitting portion and said second fitting portion form a mutually joined butt junction, said seal member is disposed at said butt junction so as to contact with said first fitting portion, second fitting portion and inner circumference, said seal member seals between said suction chamber and discharge chamber, and between said outside of the rear cover and discharge chamber, wherein said butt junction has a first chamfering portion at said first outer circumference, and has a second chamfering portion at said second outer circumference, a space surrounded by said first chamfering portion, second chamfering portion, and inner circumference forms a recess, said recess has a nearly triangular shape, and said seal member is disposed in said recess.
- 5. A scroll compressor of claim 4, wherein said fixed scroll has an end plate and a spiral blade,said movable scroll swivels at specified radius of swivel while being engaged with said fixed scroll, and said refrigerant is compressed by said fixed scroll and movable scroll.
- 6. A scroll compressor of claim 4, further comprising a rotation preventive mechanism for preventing rotation while permitting swivel motion only of said movable scroll.
- 7. A scroll compressor of claim 4, further comprisinga shaft coupled to said movable scroll in said front casing and exposed to outside from said bottom, and an electromagnetic clutch coupled to said shaft at the outside.
- 8. A scroll compressor for compressing a refrigerant comprising:(a) a front casing having an inner circumference, a bottom and an opening, (b) a fixed scroll disposed in said front casing, (c) a movable scroll disposed between said bottom and said fixed scroll, (d) a rear cover disposed to cover said opening, (e) a suction chamber surrounded by said inner circumference, fixed scroll, and rear cover, (f) a discharge chamber surrounded by said inner circumference, fixed scroll, and rear cover, and (g) a seal member, and (h) a rotation preventive mechanism for preventing rotation while permitting swivel motion only of said movable scroll, wherein said fixed scroll has a first fitting portion and a first outer circumference fitted to said inner circumference, said rear cover has a second fitting portion, and a second outer circumference fitted to said inner circumference, said first fitting portion and said second fitting portion form a mutually joined butt junction, said seal member is disposed at said butt junction so as to contact with said first fitting portion, second fitting portion and inner circumference, said seal member seals between said suction chamber and discharge chamber, and between said outside of the rear cover and discharge chamber, said first outer circumference has a first chamfering portion, said second outer circumference has a second chamfering portion, said butt junction has a nearly triangular recess surrounded by said first outer circumference, second outer circumference, and inner circumference, said seal member is disposed in said recess, said fixed scroll has an end plate fitted to said inner circumference, said first fitting portion to be fitted concentrically to said rear cover, and a spiral blade disposed at the opposite side of said first fitting portion, said movable scroll is engaged with said fixed scroll, and swivels at a specified radius of swivel, and said refrigerent is compressed by said fixed scroll and movable scroll.
- 9. The scroll compressor of claim 8, further comprising a shaft coupled to said movable scroll in said front casing and exposed to outside from said bottom, andan electromagnetic clutch coupled to said shaft at the outside.
Priority Claims (1)
Number |
Date |
Country |
Kind |
10-282444 |
Oct 1998 |
JP |
|
US Referenced Citations (2)
Number |
Name |
Date |
Kind |
4411604 |
Terauchi |
Oct 1983 |
|
5569028 |
Yamamura et al. |
Oct 1996 |
|
Foreign Referenced Citations (2)
Number |
Date |
Country |
63-158594 |
Oct 1988 |
JP |
09166095 |
Jun 1997 |
JP |