U.S. patent application number 11/904945 was filed with the patent office on 2008-04-03 for lubricating oil feeding mechanism in a swash type compressor.
Invention is credited to Tetsuhiko Fukanuma, Takayuki Imai, Masakazu Murase, Hiroki Nagano, Naoya Yokomachi.
Application Number | 20080078621 11/904945 |
Document ID | / |
Family ID | 38582263 |
Filed Date | 2008-04-03 |
United States Patent
Application |
20080078621 |
Kind Code |
A1 |
Imai; Takayuki ; et
al. |
April 3, 2008 |
Lubricating oil feeding mechanism in a swash type compressor
Abstract
Lubricating oil feeding mechanism has an oil-collecting recess
and an oil-supplying groove formed on the wall of the housing. The
oil-collecting recess connects a gap defined between the through
hole and the bolt to the oil-supplying groove, the gap being in the
upper position with respect to a sliding part to be lubricated in
the housing in an operating state of the mounted compressor. The
oil-collecting recess extends from the gap in the circumferential
direction of the drive shaft, and the oil-supplying groove upwardly
extends toward the oil-collecting recess. The oil-supplying groove
is arranged so as to guide lubricating oil to the sliding part.
Lubricating oil adhered on the bolt can be collected to the
oil-collecting recess via the gap, and is fed to the sliding part
through the oil-supplying groove. Therefore, a large amount of
lubricating oil in a swash plate chamber can be utilized to
lubricate the sliding part.
Inventors: |
Imai; Takayuki; (Kariya-shi,
JP) ; Murase; Masakazu; (Kariya-shi, JP) ;
Nagano; Hiroki; (Kariya-shi, JP) ; Yokomachi;
Naoya; (Kariya-shi, JP) ; Fukanuma; Tetsuhiko;
(Kariya-shi, JP) |
Correspondence
Address: |
MORGAN & FINNEGAN, L.L.P.
3 World Financial Center
New York
NY
10281-2101
US
|
Family ID: |
38582263 |
Appl. No.: |
11/904945 |
Filed: |
September 27, 2007 |
Current U.S.
Class: |
184/6.17 ;
417/269 |
Current CPC
Class: |
F04B 27/109
20130101 |
Class at
Publication: |
184/6.17 ;
417/269 |
International
Class: |
F04B 1/12 20060101
F04B001/12; F01M 11/04 20060101 F01M011/04 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 28, 2006 |
JP |
P2006-263871 |
Claims
1. Lubricating oil feeding mechanism in a swash type compressor
having: a housing comprising a plurality of housing elements, in
which a swash plate chamber is formed for receiving a swash plate
therein, and which defines a cylinder bore therein; a plurality of
bolts arranged through the swash plate chamber and in through holes
formed on a wall of the housing for fastening the housing elements
to form the housing; a drive shaft rotatably supported by the
housing, the drive shaft being coupled to the swash plate; a piston
accommodated in the cylinder bore so as to define a compression
chamber in the cylinder bore, the piston being coupled to the swash
plate; and a suction chamber and a discharge chamber formed in the
housing respectively, both being connectable to the compression
chamber; the lubricating oil feeding mechanism comprising an
oil-collecting recess and an oil-supplying groove formed
respectively on a side wall surface being defined on the wall of
the housing and facing the swash plate chamber, wherein the
oil-collecting recess connects a gap defined between the through
hole and the bolt to the oil-supplying groove, the gap being in the
upper position with respect to a sliding part to be lubricated in
the housing in an operating state of the mounted compressor,
wherein the oil-collecting recess extends from the gap in the
circumferential direction of the drive shaft, and wherein the
oil-supplying groove extends upwardly toward the oil-collecting
recess, wherein the oil-supplying groove is arranged so that oil
guided along the oil-supplying groove is led to the sliding
part.
2. Lubricating oil feeding mechanism according to claim 1, wherein
the oil-collecting recess extends from the gap in the rotational
direction of the drive shaft.
3. Lubricating oil feeding mechanism according to claim 1, wherein
the oil-collecting recess extends from the gap in the opposite
direction of the rotational direction of the drive shaft.
4. Lubricating oil feeding mechanism according to claim 1, wherein
the oil-collecting recess has a connection groove as a part
thereof, the connection groove connecting the gap to the rest of
the oil-collecting recess, wherein the width of the connection
groove is narrower than the diameter of the through hole.
5. Lubricating oil feeding mechanism according to claim 1, wherein
the oil-collecting recess further extends downwardly from the
through hole in an operating state of the mounted compressor.
6. Lubricating oil feeding mechanism according to claim 1, wherein
the oil-collecting recess extends so that the width of the
oil-collecting recess is substantially the same as the diameter of
the through hole along the longitudinal direction of the
oil-collecting recess.
7. Lubricating oil feeding mechanism according to claim 1, further
comprising a sub oil-collecting recess extending from the gap in
the opposite direction of the extending direction of the
oil-collecting recess with respect to the gap from which the
oil-collecting recess extends.
8. Lubricating oil feeding mechanism according to claim 7, wherein
the sub oil-collecting recess extends over two of the gaps to
connect the gaps to each other.
9. Lubricating oil feeding mechanism according to claim 1, wherein
the oil-supplying groove is formed deeper than the oil-collecting
recess to promote oil flow from the oil-collecting recess to the
groove.
10. Lubricating oil feeding mechanism according to claim 1, wherein
the oil-collecting recess has a first oil-collecting recess and a
second oil-collecting recess, the first oil-collecting recess
extending from one of the gaps in the rotational direction of the
drive shaft, the second oil-collecting recess extending from
another one of the gaps in the opposite direction of the rotational
direction of the drive shaft, wherein the oil-supplying groove has
a first oil-supplying groove and a second oil-supplying groove, the
first oil-supplying groove being connected to the first
oil-collecting recess at a forward position in the rotational
direction of the drive shaft with respect to the gap connected to
the first oil-collecting recess, the second oil-supplying groove
being connected to the second oil-collecting recess at a backward
position in the rotational direction of the drive shaft with
respect to the gap connected to the second oil-collecting
recess.
11. Lubricating oil feeding mechanism in the swash type compressor
according to claim 1, wherein the housing elements include a front
housing in which the oil-collecting recess and the oil-supplying
groove are formed respectively, wherein the front housing supports
the sliding part, and the lubricating oil feeding mechanism
includes a oil-supplying aperture formed in the front housing,
wherein the oil-supplying aperture is connected to the
oil-supplying groove and extends toward the sliding part so that
oil guided along the oil-supplying groove and the oil-supplying
aperture is led to the sliding part.
12. Lubricating oil feeding mechanism in the swash type compressor
according to claim 11, the compressor having a shaft seal disposed
between the front housing and the drive shaft to prevent
refrigerant gas in the swash plate chamber from leaking outside;
wherein the sliding part is the shaft seal.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a swash type compressor
and, more particularly, to an improved lubricating oil feeding
mechanism for such compressors.
[0003] 2. Description of the Related Art
[0004] In general, swash type compressors with variable or fixed
displacement mechanism have a swash plate chamber to arrange a
swash plate therein. The compressors also have a bearing for
supporting a drive shaft coupled to the swash plate and a shaft
seal for preventing refrigerant gas in the swash plate chamber from
leaking outside. The bearing and the shaft seal are to be
lubricated by lubricating oil contained in refrigerant gas in the
swash plate chamber.
[0005] Japanese Utility Model Application Laid-Open Publication No.
57-112082 discloses a swash type compressor having a cylinder block
forming cylinder bores and a swash plate chamber therein; a drive
shaft rotatably supported on the cylinder block via radial
bearings; a swash plate coupled to the drive shaft and arranged in
the swash plate chamber; and pistons slidably arranged in the
cylinder bores and operatively engaged with the swash plate via
shoes in FIGS. 5 and 6 thereof. Further, the compressor, for
lubricating the radial bearings, has passages formed on the
cylinder block for arranging bolts therein, the passages being used
for connection between the swash plate chamber and suction
chambers; oil-collecting recesses formed on end faces of the swash
plate chamber, the recesses being connected to the passages; and
apertures formed in the cylinder block, the apertures being
connected to the recesses. In such a compressor, lubricating oil
flowing on the end faces is trapped by the recesses and guided to
the radial bearing through the apertures.
[0006] Furthermore, Japanese Patent Application Laid-Open
Publication No. 2005-171851 discloses a variable displacement swash
type compressor having a front housing forming a shaft seal chamber
therein; an oil-guiding passage formed on the front housing, the
oil-guiding passage including an oil-guiding groove and a recess
connected to the oil-guiding groove, the recess having a side wall;
a aperture formed in the front housing, the aperture connecting the
shaft seal chamber to the oil-guiding groove; a wall formed on the
front housing, the wall protruding from the bottom surface of the
recess so as to divide the recess into small areas in FIGS. 1 and 2
thereof. In such a compressor, lots of lubricating oil flowing
along the front housing inside of the compressor is trapped by the
recess and guided to the shaft seal chamber through the oil-guiding
groove and the aperture due to the fact that some lubricating oil
colliding with the side wall is collected by one area of recess,
while the other lubricating oil going beyond the wall is collected
by the other area of recess.
[0007] In the conventional arts as mentioned above, some of the
solutions are disclosed to conduct lubricating oil in the swash
plate chamber toward a sliding part to be lubricated such as the
shaft seal or the bearing. These solutions are, however, not
sufficient in view of utilizing limited lubricating oil in the
swash plate chamber more efficiently to obtain sufficient
lubrication of the sliding part in the compressor. In general,
lubricating oil in the swash plate chamber is splashed and
circulated therein by the rotation of the swash plate during
compressor operation. In such a state some amount of lubricating
oil adheres to a side wall of the swash plate chamber, and then,
flows downwardly along the side wall due to its own weight. The
compressors as mentioned above are compressors which have mechanism
for the collection of such lubricating oil flowing downwardly along
the side wall. In this connection, the inventors have found a
particularity of lubricating oil distribution in the swash plate
chamber that a large amount of lubricating oil in the swash plate
chamber tends to adhere to bolts arranged through the swash plate
chamber to fasten each housing elements, due to the fact that it is
easy for lubricating oil splashed and circulated by the rotation of
the swash plate to collide with the bolts arranged in the area of
the circulation of lubricating oil. In the compressors as mentioned
above, such the lubricating oil adhered on the bolts cannot
positively be used for the lubrication of the sliding part.
SUMMARY OF THE INVENTION
[0008] An object of the present invention is to provide a
lubricating oil feeding mechanism in a swash type compressor, which
can efficiently conduct a large amount of lubricating oil in the
swash plate chamber to the sliding part in the compressor so that
the sliding part can become more reliable.
[0009] In accordance with an aspect of the present invention, there
is provided a lubricating oil feeding mechanism in a swash type
compressor having a housing comprising a plurality of housing
elements, in which a swash plate chamber is formed for receiving a
swash plate therein, and which defines a cylinder bore therein; a
plurality of bolts arranged through the swash plate chamber and in
through holes formed on a wall of the housing for fastening the
housing elements to form the housing; a drive shaft rotatably
supported by the housing, the drive shaft being coupled to the
swash plate; a piston accommodated in the cylinder bore so as to
define a compression chamber in the cylinder bore, the piston being
coupled to the swash plate; and a suction chamber and a discharge
chamber formed in the housing respectively, both being connectable
to the compression chamber. The lubricating oil feeding mechanism
comprises an oil-collecting recess and an oil-supplying groove
formed respectively on a side wall surface being defined on the
wall of the housing and facing the swash plate chamber. The
oil-collecting recess connects a gap defined between the through
hole and the bolt to the oil-supplying groove, the gap being in the
upper position with respect to a sliding part to be lubricated in
the housing in an operating state of the mounted compressor. The
oil-collecting recess extends from the gap in the circumferential
direction of the drive shaft. The oil-supplying groove extends
upwardly toward the oil-collecting recess. The oil-supplying groove
is arranged so that oil guided along the oil-supplying groove is
led to the sliding part.
[0010] In the aspect of the present invention, lubricating oil
adhered on the bolts is collected to the gap defined between the
through holes and the bolts due to its own weight. The
oil-collecting recess collects not only lubricating oil flowing
downwardly on the side wall surface of the housing but also such
lubricating oil gathered in the gap, and then feeds the lubricating
oil collected therein by the oil-supplying groove. Lubricating oil
guided to the oil-supplying groove is, then, led to the sliding
part. Therefore, a large amount of lubricating oil in the swash
plate chamber can efficiently be conducted to the sliding part of
the compressor. Namely, this positive utilization of lubricating
oil in the swash plate chamber enables the sliding part to be come
more reliable during compressor operation.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] Other features and advantages of the invention will be
apparent from the following description taken in connection with
the accompanying drawing wherein:
[0012] FIG. 1 is a longitudinal cross-sectional view, taken along
the line A-A of FIG. 2, of a variable displacement compressor to
which the present invention is applied, as a first embodiment
thereof;
[0013] FIG. 2 is a cross-sectional view taken along the line B-B of
FIG. 1;
[0014] FIG. 3 is a cross-sectional view taken along the line C-C of
FIG. 2;
[0015] FIG. 4 is a cross-sectional view of a variable displacement
compressor showing a second embodiment of the present
invention;
[0016] FIG. 5 is a cross-sectional view of a variable displacement
compressor showing a third embodiment of the present invention;
[0017] FIG. 6 is a cross-sectional view of a variable displacement
compressor showing a fourth embodiment of the present
invention;
[0018] FIG. 7A is a partial and schematic view of lubricating oil
feeding mechanism showing another embodiment of the present
invention.
[0019] FIG. 7B is a partial and schematic view of lubricating oil
feeding mechanism showing another embodiment of the present
invention.
[0020] FIG. 7C is a partial and schematic view of lubricating oil
feeding mechanism showing another embodiment of the present
invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0021] Referring to FIGS. 1, 2 and 3, a first embodiment of the
present invention is described hereinafter. FIG. 1 shows a variable
displacement swash plate type compressor whose housing comprises a
front housing 1, a cylinder block 2, a rear housing 3 and a valve
plate unit 4 interposed between the cylinder block 2 and the rear
housing 3. These housing elements 1, 2, 3 and 4 are fastened
together as one body with a plurality (nine) of bolts 5 as shown in
FIG. 2. The front housing 1 and the cylinder block 2 define a swash
plate chamber 12 as a control chamber therebetween.
[0022] The front housing 1 and cylinder block 2 have a central
axial bore formed therein respectively for receiving a drive shaft
6 which is rotatably supported by a pair of radial bearings 7 and 9
provided in the central axial bore, wherein one end of which is
further supported by a thrust bearing 8 provided in the central
axial bore of the cylinder block 2. Furthermore, in the central
axial bore, a shaft seal 11 is disposed between the drive shaft 6
and the front housing 1 in a certain space 10 outside the radial
bearing 9 and prevents refrigerant gas in the swash plate chamber
12 from leaking outside. The drive shaft 6 is engaged with engine E
as a motor of the vehicle at the other end thereof and can be
driven by the engine E.
[0023] There are disposed a lug plate 15 and a swash plate 16
coupled to the lug plate 15 through a hinge mechanism 17 in the
swash plate chamber 12. The lug plate 15 is fixed on the drive
shaft 6 and is supported on a side wall 13 of the front housing 1
via a thrust bearing 14 provided therebetween. The swash plate 16
is supported on the drive shaft 6 slidably and movably in the
direction along the axis thereof and is connected to the hinge
mechanism 17 to be allowed to incline with respect to the axis of
drive shaft 6. Therefore, the swash plate 16 rotates together with
the lug plate 15 when the drive shaft 6 rotates, while the
inclination of the swash plate 16 changes in accordance with the
pressure control of the swash plate chamber 12. It is here noted
that each of the radial bearings 7 and 9, the thrust bearings 8 and
14, and the shaft seal 11 represents a sliding part in accordance
with the definition of the present invention.
[0024] As can be seen from FIG. 2, the cylinder block 2 has nine
cylinder bores 18 formed therein. The same number of single headed
pistons 19 is slidably accommodated in the cylinder bores 18
respectively. Each piston 19 is engaged with the swash plate 16 at
the outside thereof via a pair of shoes 20. Therefore, the rotation
motion of the drive shaft 6 is converted into the reciprocation
motion of pistons 19 through the swash plate 16 and the shoes
20.
[0025] A compression chamber 21 is defined in the cylinder bore 18
on the right side of FIG. 1 in association with piston 19 and the
valve plate unit 4. There are provided a suction chamber 22 as a
suction pressure region and a discharge chamber 23 as a discharge
pressure region respectively in the rear housing 3.
[0026] As each piston 19 moves from the top dead center to the
bottom dead center in the associated cylinder bore 18, the
refrigerant gas in the suction chamber 22 is sucked up into the
compression chamber 21 through an associated suction port 24 formed
on the valve plate unit 4, causing an associated suction valve 25
disposed in the valve plate unit 4 to flex to an open position.
Further, as each piston 19 moves from the bottom dead center to the
top dead center in the associated cylinder bore 18, the refrigerant
gas in the compression chamber 21 is compressed to a certain
pressure level and is discharged out into the discharge chamber 23
through an associated discharge port 26 formed on the valve plate
unit 4, causing an associated discharge valve 27 disposed in the
valve plate unit 4 to flex to an open position.
[0027] The suction chamber 22 is connected with the swash plate
chamber 12 by a release passage 28 which is formed in the cylinder
block 2 and the valve plate unit 4. The discharge chamber 23 is
connected with the swash plate chamber 12 by a supply passage 29
which is formed in the cylinder block 2, the valve plate unit 4 and
the rear housing 3. The supply passage 29 is regulated by a
displacement control device 31 including a control valve 30, which
is accommodated in the rear housing 3.
[0028] Therefore, the pressure in the swash plate chamber 12 can be
controlled by the control valve 30. When the control valve 30 opens
the supply passage 29, the refrigerant gas in the discharge chamber
23 is permitted to flow into the swash plate chamber 12 via the
supply passage 29 and to make the pressure in the swash plate
chamber 12 be high. On the other hand, when the control valve 30
closes the supply passage 29, the refrigerant gas in the discharge
chamber 23 is not permitted to flow into the swash plate chamber 12
via the supply passage 29. Thus, the refrigerant gas in the swash
plate chamber 12 flows out to the suction chamber 22. This makes
the pressure in the swash plate chamber 12 be low. The inclination
of the swash plate 16 is determined by the pressure difference
between the pressure in the swash plate chamber 12 and the pressure
in the compression chamber 21. Therefore, the displacement of the
compressor can be controlled based on the inclination of swash
plate 16.
[0029] As shown in FIG. 1, when the pressure in the swash plate
chamber 12 is relatively low, the swash plate 16 can be at a
maximum inclination angle as indicated by a double dotted line in
the state that the swash plate 16 abuts on the lug plate 15. On the
other hand, when the pressure in the swash plate chamber 12 is
relatively high, the swash plate 16 can be at a minimum inclination
angle as indicated by a solid line.
[0030] As shown in FIG. 1, the bolt 5 has a head portion 501a, a
shank portion 501b, and a threaded end portion 501c. The head
portion 501a is sealingly engaged with the front housing 1, while
the threaded end portion 501c is threaded into a threaded bore
formed in the rear housing 3. The shank portion 501b is arranged so
as to extend through a first bore 32 as a through hole which is
formed in the front housing 1, the swash plate chamber 12, a second
bore 33 as the through hole which is formed in the cylinder block
2, and a third bore 4a which is formed in the valve plate unit 4.
As can be seen from FIG. 2, each through hole is arranged to be in
between the cylinder bores 18. The first bore 32 has a diameter
wider than the diameter of the shank portion 501b such that a gap
321 is defined therebetween. In this preferred embodiment, although
the gap 321 is defined by the shank portion 501b and the first bore
32 the gap 321 may be defined between the shank portion 501b and a
first bore having a different shape from the first bore 32. In
addition, a first bore may be shaped into other cross-sectional
configurations than circular cross-sectional configurations.
[0031] As shown in FIGS. 2 and 3, the side wall 13 has a side wall
surface 34 which faces the swash plate chamber 12. Oil-collecting
recesses 35, 36 and oil-supplying grooves 37, 38 are formed on the
side wall surface 34. The oil-collecting recess 35 is connected
with a gap 321a defined by the shank portion 501b of the bolt 5a,
while the oil-collecting recess 36 is connected with a gap 321b
defined by the shank portion 501b of the bolt 5b which is adjacent
to the bolt 5a and at a backward position in the rotational
direction of the drive shaft 6 with respect to the bolt 5a. These
gaps 321a, 321b are in the upper position with respect to the shaft
seal 11 as the sliding part to be lubricated in the housing in an
operating state of the compressor mounted on the vehicle.
[0032] The oil-collecting recess 35 is formed so as to have an
arched shape and extends from the gap 321a in the rotational
direction of the drive shaft 6 as indicated by an arrow shown in
FIG. 2. A sub oil-collecting recess 39 is formed on the side wall
surface 34 and is connected with the gap 321a in the opposite side
of the oil-collecting recess 35 with respect to the gap 321a. The
sub oil-collecting recess 39 is formed so as to have an arched
shape and extends, with a relatively short length as compared with
the oil-collecting recess 35, from the gap 321a in the opposite
direction of the rotational direction of the drive shaft 6.
[0033] On the other hand, the oil-collecting recess 36 is formed so
as to have an arched shape and extends from the gap 321b in the
opposite direction of the rotational direction of the drive shaft
6. A sub oil-collecting recess 40 is formed on the side wall
surface 34 and is connected with the gap 321b in the opposite side
of the oil-collecting recess 36 with respect to the gap 321b. The
sub oil-collecting recess 40 is formed so as to have an arched
shape and extends, with a relatively short length as compared with
the oil-collecting recess 36, from the gap 321b in the rotational
direction of the drive shaft 6. Further, the oil-collecting
recesses 35, 36 and the sub oil-collecting recesses 39, 40 extend
so that their width is substantially the same as the diameter of
the first bore 32 along the longitudinal direction thereof.
[0034] The oil-supplying groove 37 extends in the radial direction
of the drive shaft 6 and is, at the top end thereof, connected to a
forward position of the oil-collecting recess 35 in the rotation
direction of the drive shaft 6. As can be seen in FIG. 3, the
oil-supplying groove 37 is formed deeper than the oil-collecting
recess 35 to promote oil flow from the oil-collecting recess 35 to
the oil-supplying groove 37. On the other hand, the oil-supplying
groove 38 extends in the radial direction of the drive shaft 6 and
is, at the top end thereof, connected to a backward position of the
oil-collecting recess 36 in the rotation direction of the drive
shaft 6. Likewise, the oil-supplying groove 38 is formed deeper
than the oil-collecting recess 36 to promote oil flow from the
oil-collecting recess 36 to the oil-supplying groove 38. As shown
in FIGS. 1 and 2, the side wall 13 has oil-supplying apertures 41,
42 which connect the swash plate chamber 12 to the certain space
10. The oil-supplying groove 37, 38 are, at the bottom thereof,
connected with the oil-supplying apertures 41, 42 respectively so
that lubricating oil guided along the oil-supplying grooves 37, 38
and the oil-supplying apertures 41, 42 is led to the radial bearing
9 and the shaft seal 11 defined as the sliding part.
[0035] As shown in FIG. 1, there is provided a refrigerant circuit
43 incorporating the above-mentioned compressor in vehicle air
conditioners. It is here noted that the refrigerant gas such as a
natural refrigerant gas like CO.sub.2 gas (carbon dioxide) or freon
gas is used in the compressor. The refrigerant circuit 43 has, in
turn, a gas pressure reducing valve 44 connected to the discharge
chamber 23, a condenser 45, a receiver 46, an expansion valve 47,
and an evaporator 48 connected to the suction chamber 22. There is
provided a pressure sensor 49 in a conduit between the condenser 45
and the receiver 46. The pressure sensor 49 detects the pressure in
the conduit and issues signals relating to the detected pressure to
a controller (not shown). The controller is also connected to the
displacement control device 31 and controls it.
[0036] The operation of the compressor having the lubricating oil
feeding mechanism will now be described.
[0037] When the drive shaft 6 of the compressor is rotated by the
engine E, the swash plate 16 is also rotated for receiving
rotational power of the drive shaft 6 through the lug plate 15 and
the hinge mechanism 17. Rotation of the swash plate 16 gets each of
the piston 19 to be reciprocated in the cylinder bore 18 so that
refrigerant gas in the suction chamber 22 is sucked into the
compression chamber 21, and then refrigerant gas in the compression
chamber 21 is compressed and is discharged into the discharge
chamber 23.
[0038] The hinge mechanism 17 serves as an agitator so as to
agitate or splash lubricating oil contained in refrigerant gas in
the swash plate chamber 12 while the swash plate 16 is rotating
because the hinge mechanism 17 corresponds to a portion which
partially protrudes from the lug plate 15 and the swash plate 16.
When the swash plate 16 is rotated, the hinge mechanism 17 makes
lubricating oil stayed in/under the swash plate chamber 12 be
circulated therein. By that agitation, some amount of the
circulated lubricating oil in the swash plate chamber 12 adheres to
the side wall 13, an inner peripheral surface of the swash plate
chamber 12 and an end face of the cylinder block 2.
[0039] On the other hand, however, a large amount of lubricating
oil in the swash plate chamber 12 tends to adhere on the bolts 5
arranged through the swash plate chamber 12, due to the fact that
it is easy for lubricating oil splashed and circulated by the
rotation of the hinge mechanism 17 to collide with the bolts 5 as
an obstacle in the direction of the circulation of lubricating oil.
The lubricating oil adhered on the bolts 5 largely drops downwardly
toward the bottom of the swash plate chamber 12 directly due to its
own weight. The lubricating oil adhered on the bolt 5, a position
of which is located near the side wall, tends to drop into the gap
321 due to surface tension.
[0040] Lubricating oil gathered in the gaps 321a, 321b flows by its
own weight and is led to the oil-collecting recesses 35, 36.
Besides, lubricating oil adhered on the side wall surface 34 of the
side wall 13 flows downwardly by its own weight and a part of that
is collected by the oil-collecting recesses 35, 36, the sub
oil-collecting recesses 39, 40 and oil-supplying grooves 37, 38
efficiently due to their configuration. Here, lubricating oil
gathered in the sub oil-collecting recesses 39, 40 is led to the
oil-collecting recesses 35, 36 through the gaps 321a, 321b
respectively. After being collected into the oil-collecting
recesses 35, 36, lubricating oil flows in the circumferential
direction of the drive shaft 6 along the oil-collecting recesses
35, 36 by its own weight. The oil-supplying grooves 37, 38 are
formed further deeper than the oil-collecting recesses 35, 36
whereby feeding lubricating oil from the oil-collecting recesses
35, 36 to the oil-supplying groove 37, 38 can be ensured.
[0041] In addition, the revolution of the hinge mechanism 17 with
the rotation of the swash plate 16 makes not only lubricating oil
in the swash plate chamber 12 be splashed or be circulated but also
lubricating oil adhere on the side wall surface 34, in the
oil-collecting recesses 35, 36, and in the sub oil-collecting
recesses 39, 40 as well as lubricating oil gathered in the gap
321a, 321b flow in the rotational direction of the drive shaft 6 by
gas streams accompanied with the circulation of lubricating oil in
the swash plate chamber 12. For this reason, lubricating oil
adhered on the side wall surface 34 and gathered in the gaps 321a,
321b can easily be collected in the oil-collecting recesses 35, 36
and the sub oil-collecting recesses 39, 40. Especially, when the
drive shaft 6 is rotated in the direction as indicated by the arrow
shown in FIG. 2, lubricating oil in the oil-collecting recess 35
and lubricating oil below the oil-collecting recess 35 can easily
be fed to the oil-supplying groove 37 as compared with that in the
oil-collecting recess 36. In contrast to that, in case where the
drive shaft 6 is rotated in the opposite direction of the
rotational direction as indicated by the arrow shown in FIG. 2,
lubricating oil in the oil-collecting recess 36 and lubricating oil
below the oil-collecting recess 36 can easily be fed to the
oil-supplying groove 38 as compared with that in the oil-collecting
recess 35.
[0042] Lubricating oil supplied in the oil-supplying grooves 37, 38
are further guided to the certain space 10 through the
oil-supplying apertures 41, 42 so that the certain space 10 can be
filled with a large amount of lubricating oil. Therefore, the shaft
seal 11 can sufficiently be lubricated. Also, the radial bearing 9
can sufficiently be lubricated. This makes the sliding part such as
the shaft seal 11 and the radial bearing 9 much more durable.
[0043] The first embodiment of the present invention has the
following advantages.
[0044] The oil-collecting recesses 35, 36 is connected with the gap
321a, 321b so that lubricating oil collided with the bolts 5 in the
route of the circulation of lubricating oil caused by the
revolution of the hinge mechanism 17, a portion of which is located
near the gap 321a, 321b can effectively be collected into the
oil-collecting recesses 35, 36. Therefore, such the lubricating oil
adhered on the bolts 5 can positively be utilized for lubrication
of the sliding part.
[0045] The oil-collecting recesses 35, 36 are arranged extending in
the circumferential direction of the drive shaft 6. Therefore,
lubricating oil gathered in the gaps 321a, 321b and adhered on the
side wall surface 34 can efficiently be collected by the
oil-collecting recesses 35, 36. As a result, lubrication for the
sliding part can be ensured.
[0046] The oil-supplying groove 37 is connected to the
oil-collecting recess 35 at the forward position in the rotational
direction of the drive shaft 6 with respect to the gap 321a. Due to
the revolution of the hinge mechanism 17 with the rotation of the
swash plate 16, lubricating oil flows in the rotational direction
of the drive shaft 6 led by gas streams accompanied with the
circulation of lubricating oil in the swash plate chamber 12, thus,
lubricating oil in the oil-collecting recess 35 and lubricating oil
below the oil-collecting recess 35 can more easily be fed to the
oil-supplying groove 37.
[0047] While the oil-collecting recess 35 is arranged extending
downwardly from the gap 321a in the rotational direction of the
drive shaft 6, the oil-collecting recess 36 is arranged extending
downwardly from the gap 321b in the opposite direction of the
rotational direction of the drive shaft 6. Therefore, lubricating
oil collecting ability of the bolts 5 can be ensured due to the own
weight of lubricating oil.
[0048] The lubricating oil feeding mechanism comprising the
oil-collecting recesses 35, 36 and the oil-supplying grooves 37, 38
can easily be provided due to the fact that a recess and a groove
have only to be formed on the side wall 13.
[0049] The present invention may be alternatively embodied in the
following forms:
[0050] FIG. 4 shows a lubricating oil feeding mechanism according
to a second embodiment. In the second embodiment, component parts
and elements corresponding to those of the above first embodiment
are indicated by identical reference numerals, and a description
thereof is omitted. There is provided an oil-collecting recess 50
formed on the side wall 13, the oil-collecting recess 50 extending
from the gap 321a in the rotational direction of the drive shaft 6.
The oil-collecting recess 50 has a connection groove 51 as a part
thereof, the connection groove 51 connecting the gap 321a to the
rest of the oil-collecting recess 50. The width of the connection
groove 51 is arranged narrower than the diameter of the first bore
32 as well as the width of the rest of the oil-collecting recess 50
in view of the radial direction of the drive shaft 6. There are
also provided an oil-supplying groove 52 and an oil-supplying
aperture 53 on the side wall 13. The oil-supplying groove 52 is
connected to the oil-collecting recess 50 at approximately the
middle point thereof. The oil-supplying aperture 53 connects the
oil-supplying groove 52 to the certain space 10 shown in FIG.
1.
[0051] Since stress concentration is likely to take place around
the first bore 32 under strong fastening power by the bolts 5, in
this case, it may be difficult in view of the strength required for
the front housing 1 that an oil-collecting recess 50 is formed
being connected to all around the circumference of the first bore
32 with a cutting process. According to the second embodiment,
however, the connection groove 51 connected with the first bore 32
is arranged narrower than the diameter of the first bore 32.
Therefore, the stress concentration to be generated around the
first bore 32 can be reduced.
[0052] FIG. 5 shows a lubricating oil feeding mechanism according
to a third embodiment. In the third embodiment, component parts and
elements corresponding to those of the above first embodiment are
indicated by identical reference numerals, and a description
thereof is omitted. What is different from the first embodiment is
that a sub oil-collecting recess 54 extends over two of the gaps
321a, 321b to connect the gap 321a to the gap 321b. The sub
oil-collecting recess 54 extends from the gap 321a in the opposite
direction of the extending direction of the oil-collecting recess
35 with respect to the gap 321a. According to the third embodiment,
since the length of the sub oil-collecting recess 54 becomes long,
lubricating oil collecting ability on the side wall surface 34 can
be enhanced.
[0053] FIG. 6 shows a lubricating oil feeding mechanism according
to a fourth embodiment. In the fourth embodiment, component parts
and elements corresponding to those of the above first embodiment
are indicated by identical reference numerals, and a description
thereof is omitted. There is provided an oil-collecting recess 55
extending from a gap 321c defined by the first bore 32 and the
shank portion 501b of the bolt 5c in the rotational direction of
the drive shaft 6, the gap 321c being adjacent to the gap 321a and
being in the upper position with respect to the shaft seal 11 as
the sliding part to be lubricated in the housing in an operating
state of the mounted compressor. There are further provided a first
sub oil-collecting recess 56 and a second sub oil-collecting recess
57 on the side wall 13. The first sub oil-collecting recess 56
extends over two of the gaps 321a, 321c to connect the gap 321a to
the gap 321c, and has an arched shape. The second sub
oil-collecting recess 57 extends from the gap 321a in the opposite
direction of the rotation of the drive shaft 6. There is provided
an oil-supplying groove 58 which connects the oil-collecting recess
55 to the oil-supplying aperture 41. The oil-supplying groove 58 is
arranged to be connected with the oil-supplying recess 55 at a
forward position thereof in the rotational direction of the drive
shaft 6.
[0054] According to the fourth embodiment, lubricating oil adhered
on the bolt 5a flows to the first sub oil-collecting recess 56
through the gap 321a. Also, lubricating oil adhered on the bolt 5c
flows to the oil-collecting recess 55 through the gap 321c together
with lubricating oil flowing in the first sub oil-collecting recess
56. On the other hand, the second sub oil-collecting recess 57
collects lubricating oil adhering on the side wall surface 34 and
guides the lubricating oil to the oil-collecting recess 55 through
the gap 321a, the first sub oil-collecting recess 56 and the gap
321c in turn. The oil-collecting recess 55 as well as the first sub
oil-collecting 56 can collect lubricating oil adhering on the side
wall surface 34 as same as in the first embodiment described
above.
[0055] Lubricating oil collected in the oil-collecting recess 55 is
guided along the oil-supplying groove 58 and is led to the certain
space 10 shown in FIG. 1 through the oil-supplying aperture 41.
Since the first sub oil-collecting recess 56 is arranged over the
gaps 321a, 321c, therefore, the lubricating oil collecting ability
can be improved. Furthermore, since lubricating oil collected in
the oil-collecting recess 55 can be guided by the oil-supplying
groove 58 only, lubricating oil feeding mechanism can further be
simplified.
[0056] The present invention may further be embodied in the
following forms:
[0057] FIGS. 7A, 7B and 7C show some other lubricating oil feeding
mechanism than those described above, in that the relationship
between an oil-collecting recess and an oil-supplying groove is
modified. In the modification described below, component parts and
elements corresponding to those of the above first embodiment are
indicated by identical reference numerals, and description thereof
is omitted.
[0058] FIG. 7A shows an oil-collecting recess 59 extending from the
gap 321a not only in the rotational direction of the drive shaft 6
shown in FIG. 1 but also downwardly in the radial direction of the
drive shaft 6 so as to be sloped with respect to an oil-supplying
groove 60. Furthermore, the oil-collecting recess 59 extends so
that its width is substantially the same as the diameter of the
first bore 32 along the longitudinal direction of the
oil-collecting recess 59. In addition, the oil-collecting recess 59
is formed so that its depth is substantially the same as that of
the oil-supplying groove 60. The oil-supplying groove 60 is, at the
middle point thereof, connected with the oil-collecting recess
59.
[0059] FIG. 7B shows an oil-collecting recess 61 extending from the
gap 321a and spreading over at the point of the connection between
the oil-collecting recess 61 and an oil-supplying groove 64. The
oil-collecting recess 61 has an upper wall 62 and a lower wall 63,
the upper wall 62 being formed straight and being connected to an
upper wall of the oil-supplying groove 64, and the lower wall 63
being formed away from the upper wall 62 as closing with the
oil-supplying groove 64.
[0060] FIG. 7C shows an oil-collecting recess 65 extending from the
gap 321a in the rotational direction of the drive shaft 6 shown in
FIG. 1 and being formed bent downwardly in the radial direction of
the drive shaft 6. There is provided an oil-supplying groove 66
extending to a forward position of the oil-collecting recess 65 in
the radial direction of the drive shaft 6.
[0061] In addition, it is possible to omit the sub oil-collecting
recesses 39, 40 in the first embodiment, and also possible to omit
the sub oil-collecting recess 57 in the fourth embodiment.
[0062] In the first embodiment, the oil-supplying grooves 37, 38
may be connected to the oil-collecting recesses 35, 36 at
approximately the middle point thereof respectively.
[0063] In the first embodiment, it is not necessarily required to
make the oil-supplying grooves 37, 38 deeper than the
oil-collecting recesses 35, 36. it may be implemented that both of
the grooves 37, 38 and recesses 35, 36 have the same depth.
[0064] In the fourth embodiment, in addition to the lubricating oil
feeding mechanism described before, a first sub oil-collecting
recess connects the gap 321b to a gap 321d which is in the upper
position with respect to the shaft seal 11 as sliding part to be
lubricated in the housing in an operating state of the mounted
compressor. Also, a second sub oil-collecting recess is connected
to the gap 321b, and an oil-collecting recess is connected to the
gap 321d, the oil-collecting recess being connected to an
oil-supplying groove. Although both of those mechanism are adopted
together so as to collect lubricating oil gathered in the gaps
321a, 321b, 321c and 321d, only one of the described mechanism
might be used to improve the lubricativity.
[0065] In the fourth embodiment, the oil-supplying groove 58 is
connected to the sub oil-collecting recess 56. In this embodiment,
the sub oil-collecting recess 56 represents an oil-collecting
recess, and the oil-collecting recess 55 represents a sub
oil-collecting recess.
[0066] In each embodiment described above, the shape of each
oil-collecting recess 35, 36, 50 and 55, each sub oil-collecting
recess 39, 40, 54 and 56, and the connection groove 51 is formed
arched. It may, however, be possible to form each recess and the
groove mentioned above to a straight shape or a wave shape.
[0067] The present invention may be embodied in compressors other
than the compressors of FIG. 1. For example, the present invention
may be embodied in fixed displacement swash type compressor,
double-headed piston swash type compressor.
[0068] Finally, it will be understood by those skilled in the art
that the foregoing description is of preferred embodiments of the
disclosed invention, and that various changes and modifications may
be made to the present invention without departing from the spirit
and scope thereof.
* * * * *