U.S. patent application number 10/430210 was filed with the patent office on 2003-11-13 for compressors.
Invention is credited to Matsuoka, Tamotsu, Tagami, Shinji, Takai, Kazuhiko.
Application Number | 20030210989 10/430210 |
Document ID | / |
Family ID | 29397410 |
Filed Date | 2003-11-13 |
United States Patent
Application |
20030210989 |
Kind Code |
A1 |
Matsuoka, Tamotsu ; et
al. |
November 13, 2003 |
Compressors
Abstract
A compressor includes a suction chamber, a crank chamber, and a
drive shaft extending through the crank chamber. The drive shaft
includes a passage formed therein, and a hole formed therein. For
example, the hole may be formed through the drive shaft. The
compressor also includes a path communicating between the crank
chamber and the suction chamber. Specifically, the path includes
the passage and the hole.
Inventors: |
Matsuoka, Tamotsu;
(Sawa-gun, JP) ; Takai, Kazuhiko; (Sawa-gun,
JP) ; Tagami, Shinji; (Sawa-gun, JP) |
Correspondence
Address: |
Baker & Botts, L.L.P.
The Warner
1299 Pennsylvanis Avenue, N. W.
Washington
DC
20004-2400
US
|
Family ID: |
29397410 |
Appl. No.: |
10/430210 |
Filed: |
May 7, 2003 |
Current U.S.
Class: |
417/222.2 |
Current CPC
Class: |
F04B 27/1036 20130101;
F04B 27/109 20130101; F04B 27/1804 20130101; F04B 2027/1827
20130101; F04B 2027/1895 20130101 |
Class at
Publication: |
417/222.2 |
International
Class: |
F04B 001/26 |
Foreign Application Data
Date |
Code |
Application Number |
May 8, 2002 |
JP |
133147/2002 |
Claims
What is claimed is:
1. A compressor comprising: a suction chamber; a crank chamber; a
drive shaft extending through the crank chamber, wherein the drive
shaft comprises: a passage formed in the drive shaft; and a hole
formed in the drive shaft; and a path communicating between the
crank chamber and the suction chamber, wherein the path comprises
the passage and the hole.
2. The compressor of claim 1, further comprising: a swash plate
rotatably mounted on the drive shaft; and a rotor fixedly mounted
on the drive shaft, wherein the rotor is operationally connected to
the swash plate.
3. The compressor of claim 1, wherein the rotor comprises: a front
rotor wall; and a rear rotor wall, wherein the front rotor wall is
a first predetermined distance from the swash plate, the rear rotor
wall is a second predetermined distance from the swash plate, and
the first predetermined distance is greater than the second
predetermined distance.
4. The compressor of claim 3, wherein a center of the hole is a
third predetermined distance from the front rotor wall, the center
of the hole is a fourth predetermined distance from the rear rotor
wall, and the third predetermined distance is greater than the
fourth predetermined distance.
5. The compressor of claim 2, wherein the rotor comprises: a front
rotor wall; and a rear rotor wall, wherein the swash plate
comprises: a front plate wall; and a rear plate wall, wherein: the
font rotor wall is a first distance from the front plate wall; the
front rotor wall is a second distance from the rear plate wall; the
rear rotor wall is a third distance from the front plate wall the
rear rotor wall is a fourth distance from the rear plate wall; the
first distance is greater than the third distance; and the second
distance is greater than the fourth distance.
6. The compressor of claim 5, wherein when an inclination angle of
the swash plate is equal to a maximum inclination angle, the hole
is positioned between the rear rotor wall and the front plate
wall.
7. The compressor of claim 6, wherein the hole is substantially
cylindrical shaped.
8. The compressor of claim 6, wherein the hole is substantially
conical shaped.
9. The compressor of claim 6, wherein the hole is perpendicular to
the passage.
10. The compressor of claim 6, wherein the hole is slanted relative
to the passage.
11. The compressor of claim 6, further comprising a extension pipe,
wherein a first portion of the extension pipe is positioned within
the bole, and a second portion of the extension pipe is positioned
outside the hole.
12. The compressor of claim 11, wherein the first portion is
substantially cylindrical shaped.
13. The compressor of claim 11, wherein the first portion is
perpendicular to the passage.
14. The compressor of claim 11, wherein the first portion is
slanted relative to the passage.
15. The compressor of claim 11, wherein the second portion is
substantially cylindrical shaped.
16. The compressor of claim 11, wherein the second portion is
substantially conical shaped.
17. The compressor of claim 11, wherein the second portion is
perpendicular to the passage.
18. The compressor of claim 11, wherein the second portion is
slanted relative to the passage
19. The compressor of claim 1, wherein the hole is formed through
the drive shaft.
20. The compressor of claim 1, wherein a center of the hole
comprises an opening of the passage.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates generally to compressors. In
particular, the present invention is directed towards compressors
having a hole formed through a drive shaft of the compressor for
separating a lubricant from a refrigerant.
[0003] 2. Description of Related Art
[0004] Known compressors may be used in an air conditioning system.
Specifically, such air conditioning systems include a refrigeration
circuit, and the refrigeration circuit may include the compressor.
Such known compressors include a swash plate or a cam plate
positioned within a crank chamber, and a piston which reciprocates
within a cylinder bore. An inclination angle of the plate varies in
response to a pressure in the crank chamber, and the inclination
angle determines a stroke length of the piston. Specifically, when
the pressure in the crank chamber increases, the inclination angle
and the stroke length of the piston decrease. Similarly, when the
pressure in the crank chamber decreases, the inclination angle and
the stroke length of the piston increase. Moreover, when the piston
moves away from the suction chamber, the piston draws a
refrigerant, e.g., a liquid refrigerant or a refrigerant gas, from
the suction chamber into the cylinder bore. Similarly, when the
piston moves toward the suction chamber, the piston compresses the
refrigerant within the cylinder bore and discharges the compressed
refrigerant into a discharge chamber.
[0005] Such known compressors also include a first path which
allows refrigerant communication between the crank chamber and the
discharge chamber, and a second path which allows refrigerant
communication between the crank chamber and the suction chamber.
The pressure in the crank chamber increases when the refrigerant
flows from the discharge chamber to the crank chamber. The pressure
in the crank chamber also increases when the piston compresses the
refrigerant, and blow-by gas flows into the crank chamber via a gap
formed between the piston and the cylinder bore. Conversely, the
pressure in the crank chamber decreases when the refrigerant and
the blow-by gas flows from the crank chamber to the suction
chamber.
[0006] Moreover, a lubricant, e.g., a lubricating oil, is sealed in
the crank chamber for lubricating moving parts of the compressor,
e.g., the plate, the piston, and the like. Specifically, when the
refrigerant and the blow-by gas flow into the crank chamber, the
lubricant is carried along the flow path of the refrigerant and the
flow path of the blow-by gas within the crank chamber to lubricate
the moving parts of the compressor. Nevertheless, the distribution
of the lubricant within the crank chamber is limited to the flow
path of the refrigerant and the flow path of the blow-by gas.
Moreover, at least a portion of the lubricant is carried by the
refrigerant and the blow-by gas into the suction chamber, such that
the carried portion of the lubricant enters the refrigeration
circuit. When the carried portion of the lubricant enters the
refrigeration circuit, the efficiency of the air conditioning
system decreases.
SUMMARY OF THE INVENTION
[0007] Therefore, a need has arisen for compressors which overcome
these and other shortcomings of the related art. A technical
advantage of the present invention is that the amount of lubricant
which enters the refrigeration circuit is reduced relative to the
amount of lubricant which enters the refrigeration circuit in the
known compressors.
[0008] In an embodiment of the present invention, a compressor
comprises a suction chamber, a crank chamber, and a drive shaft
extending through the crank chamber. The drive shaft comprises a
passage formed in the drive shaft, and a hole formed in the drive
shaft. For example, the hole may be formed through the drive shaft.
The compressor also comprises a path communicating between the
crank chamber and the suction chamber. Specifically, the path
comprises the passage and the hole.
[0009] Other objects, features, and advantage will be apparent to
persons of ordinary skill in the art from the following detailed
description of the invention and the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] For a more complete understanding of the present invention,
the needs satisfied thereby, and the objects, features, and
advantages thereof, reference now is made to the following
description taken in connection with the accompanying drawings.
[0011] FIG. 1 is a cross-sectional view of a compressor according
to an embodiment of the present invention.
[0012] FIG. 2 is a side view of a drive shaft of a compressor
according to an embodiment of the present invention.
[0013] FIG. 3 is a partial, cutaway view of the drive shaft of FIG.
2.
[0014] FIG. 4 is a side view of a drive shaft of a compressor
according to another embodiment of the present invention.
[0015] FIG. 5 is a partial, cutaway view of the drive shaft of FIG.
4.
[0016] FIG. 6 is a side view of a drive shaft of a compressor
according to still another embodiment of the present invention.
[0017] FIG. 7 is a partial, cutaway view of the drive shaft of FIG.
6.
[0018] FIG. 8 is a partial, cutaway view of a drive shaft of a
compressor according to yet another embodiment of the present
invention.
[0019] FIG. 9 is a partial, cutaway view of a drive shaft of a
compressor according to still yet another embodiment of the present
invention.
[0020] FIG. 10 is a partial, cutaway view of a drive shaft of a
compressor according to a further embodiment of the present
invention.
[0021] FIG. 11 is a partial, cutaway view of a drive shaft of a
compressor according to still a further embodiment of the present
invention.
DETAILED DESCRIPTION OF PREFERRED EMBODJMNTS
[0022] Preferred embodiments of the present invention and their
features and advantages may be understood by referring to FIGS.
1-11, like numerals being used for like corresponding parts in the
various drawings.
[0023] Referring to FIG. 1, a compressor 100 according to an
embodiment of the present invention is depicted. Compressor 100 may
comprise a cylinder block 50 and a crankcase 51 fixed to a front
end of the cylinder block 50. In an embodiment, crankcase 51 may
comprise a boss portion 51b, and a pulley 56 may be fitted on boss
portion 51b via a radial bearing 57. Pulley 56 may be operationally
connected to a driving source (not shown), e.g., an engine of a
vehicle, via a belt (not shown). Cylinder block 50 and crankcase 51
may define a crank chamber 41. Cylinder block 50 and crankcase 51
each may have a center hole 50a and 51a formed therethrough,
respectively. Cylinder block 50 and crankcase 51 also may support a
drive shaft 52 via a pair of radial bearings 53 and 54 positioned
within center holes 50a and 51a, respectively. Drive shaft 52
extends in an axial direction within compressor 100, and a front
end 52a of drive shaft 52 extends through crank chamber 41 and into
crankcase 51. First end 52a of drive shaft 52 may be operationally
connected to pulley 56 via a plate spring 58 and a connection
member 59. A gap formed between center hole 51a and drive shaft 52
may be sealed by a seal lip 55. In another embodiment of the
present invention, pulley 56 and the belt may include an
electromagnetic clutch (not shown), such that first end 52a of
drive shaft 52 may be operationally connected to pulley 56 via the
electromagnetic clutch.
[0024] Cylinder block 50 may have a plurality of cylinder bores 60
formed therein, and cylinder bores 60 may extend in an axial
direction toward crank chamber 41. In an embodiment, compressor 100
may comprise an odd number of cylinder bores, e.g., seven cylinder
bores. Compressor 100 also may comprise a plurality of pistons 62,
and each piston 62 may be positioned within a corresponding one of
cylinder bores 60, such that each piston 62 reciprocates
independently within its corresponding cylinder bore 60. Moreover,
a valve plate 61 may be fixed to cylinder block 50 to enclose each
piston 62 within its corresponding cylinder bore 60. Valve plate 61
may have a suction port 61a and a discharge port 61b formed
therethrough, and a cylinder head 63 may be fixed to valve plate
61. A suction chamber 42 and a discharge chamber 43 may be formed
within cylinder head 63, and suction chamber 42 and discharge
chamber 43 may be in refrigerant communication with cylinder bores
60 via suction port 61a and discharge port 61b, respectively. A
control valve assembly 64 may be positioned within cylinder head
63. Control valve assembly 64 may be in fluid communication with
discharge chamber 43 via a first passage 65 formed in cylinder head
63. Control valve assembly 64 also may be in fluid communication
with suction chamber 42 via a second passage 66. Second passage 66
may be formed through cylinder block 50, valve plate 61, and
cylinder head 63.
[0025] Compressor 100 also may comprise a rotor 67 mounted on drive
shaft 52, and a swash plate 69. Rotor 67 may be positioned within
crank chamber 41, and rotates when drive shaft 52 rotates.
Crankcase 51 may support rotor 67 via a thrust bearing 68. Rotor 67
may comprise a first arm portion 67a having an elongated hole 67b
formed therethrough. Swash plate 69 may comprise a second arm
portion 69a, and a pin 69b. Pin 69b may be positioned within hole
67b and is movable within hole 67b, such that an inclination angle
of swash plate 69 may be varied. Compressor 100 also may comprise a
plurality of shoe pairs 70, and a peripheral portion of swash plate
69 may be positioned between a first and a second shoe of shoe pair
70. Shoes pairs 70 may be supported by shoe supporters 62a which
are formed integrally with pistons 62, and each shoe 70 may slide
on an inner surface of a corresponding one of shoe supporters 62a.
Thus, swash plate 69 may be coupled to pistons 62 via shoes pairs
70. When drive shaft 52 rotates, swash plate 69 also rotates.
Moreover, swash plate 69 slides between shoe pairs 70, and pistons
62 reciprocate within their corresponding cylinder bore 60.
[0026] In an embodiment of the present invention, drive shaft 52
may comprise a connection hole 20 formed therethrough, and a drive
shaft passage 10 formed therein. Drive shaft passage 10 may extend
in the axial direction from a rear end 52b of drive shaft 52, and
the length of drive shaft passage 10 may be less than the length of
drive shaft 52, such that drive shaft passage 10 does not reach
first end 52a of drive shaft 52. First passage 52 may intersect
with connection hole 20, such that connection hole 20 forms an
opening for first passage 52. Drive shaft passage 10 may be in
fluid communication with crank chamber 41 via connection hole 20.
Drive shaft passage 10 also may in fluid communication with suction
chamber 42 via center hole 50a and a third passage 71. Third
passage 71 may be formed through cylinder block 50 and valve plate
61. Moreover, connection hole 20, drive shaft passage 10, center
hole 50a, and third passage 71 may form a path which allows
refrigerant communication between crank chamber 41 and suction
chamber 42.
[0027] In this embodiment of the present invention, connection hole
20 may be positioned between rotor 67 and swash plate 69. For
example, rotor 67 may comprise a front rotor wall 67d and a rear
rotor wall 67c, swash plate 69 may comprise a front plate wall 69c
and a rear plate wall 69d, and rear rotor wall 67c may face front
plate wall 69c. In general, connection hole 20 may be positioned
more proximate to rear rotor wall 67c than to front rotor wall 67d.
For example, connection hole 20 may be positioned between a first
location P1 and a second location P2, in which first location P1
corresponds to a location of rear rotor wall 67c, and second
location P2 corresponds to a location of front plate wall 69c when
an inclination angle of swash plate 69 is at a maximum inclination
angle. In another example, connection hole 20 may be positioned
between second location P2 and a third location P3, in which third
location P3 corresponds to a location of rear plate wall 69d when
the inclination angle of swash plate 69 is at the maximum
inclination angle. In yet another example, connection hole 20 may
be positioned between third location P3 and a fourth location P4,
in which fourth location P4 corresponds to a location of front
plate wall 69c when the inclination angle of swash plate 69 is at a
minimum inclination angle.
[0028] During compressor operation, the refrigerant generally flows
along a first flow path indicated by a first plurality of arrows
F1, F2, F5, and F6, and the blow-by gas generally flows along a
second flow path indicated by a second plurality of arrows F3, F4,
F5, and F6. Specifically, the refrigerant may enter a lower portion
of crank chamber 41 via second passage 66, and then may enter drive
shaft passage 10 via connection hole 20. Similarly, the blow-by gas
may enter an upper portion of crank chamber 41 via a gap formed
between cylinder bore 60 and a corresponding one of pistons 62, and
then may enter drive shaft passage 10 via connection hole 20. The
refrigerant and the blow-by gas may combine within drive shaft
passage 10, and then may flow into suction chamber 42 via drive
shaft passage 10, center hole 50a, and third passage 71.
[0029] When the refrigerant or the blow-by gas flows within crank
chamber 41, a lubricant sealed within crank chamber 41 also may
flow with the refrigerant or the blow-by gas toward connection hole
20. When the lubricant is proximate to connection hole 20, a first
portion of the lubricant may flow with the refrigerant or the
blow-by gas into drive shaft passage 10. Nevertheless, a second
portion of the lubricant also may contact the outer surface of
drive shaft 52, and separate from the refrigerant or the blow-by
gas. Moreover, because drive shaft 52 rotates during compressor
operation, the centrifugal force generated by drive shaft 52 causes
the separated lubricant to scatter along the outer surface of drive
shaft 52. As such, the movement of the separated lubricant may be
independent from the flow of the refrigerant and the blow-by gas
within crank chamber 41, and the moving components of compressor
100 may be more sufficiently lubricated than the moving components
in known compressors. Moreover, because the second portion of the
lubricant may not enter suction chamber 42, the efficiency of an
air conditioning system comprising compressor 100 may be greater
than the efficiency of known air conditioning systems.
[0030] Referring to FIGS. 2 and 3, in an embodiment, connecting
hole 20 may be formed perpendicular to drive shaft passage 10, and
may have a cylindrical shape. Connecting hole 20 also may be formed
through drive shaft 52, or as shown in FIG. 11, connecting hole 20
may be formed within drive shaft 52. Referring to FIGS. 4 and 5, in
another embodiment, connecting hole 20 may be slanted relative to
drive shaft passage 10 (as shown by reference numeral 21).
Specifically, slanting connecting hole 20 relative to drive shaft
passage 10 may alter the direction in which the second portion of
the lubricant scatters. referring to FIGS. 6 and 7, in yet another
embodiment, connecting hole 20 may have a conical shape (as shown
by reference numeral 22), such that a diameter of connecting hole
20 may decrease between the outside of drive shaft 52 and a center
of drive shaft 52. Referring to FIGS. 8-10, in still another
embodiment, at least a portion of a pipe 30 may be positioned
within connection hole 20. Pipe 20 may extend a length of
connecting hole 20, such that an amount of the lubricant which
separates from the refrigerant may increase. For example, a first
portion of pipe 30 may be cylindrical shaped and positioned within
connection hole 20. Moreover, a second portion of pipe 30 may be
positioned outside connection hole 20. The second portion of pipe
30 may be cylindrical shaped, conical shaped, or the like. The
second portion of pipe 30 also may be substantially perpendicular
to drive shaft passage 10, or may be slanted relative to drive
shaft passage 10.
[0031] While the invention has been described in connection with
preferred embodiments, it will be understood by those skilled in
the art that variations and modifications of the preferred
embodiments described above may be made without departing from the
scope of the invention. Other embodiments will be apparent to those
skilled in the art from a consideration of the specification or
from a practice of the invention disclosed herein. It is intended
that the specification and the described examples are consider
exemplary only, with the true scope of the invention indicated by
the following claims.
* * * * *