U.S. patent application number 10/169440 was filed with the patent office on 2003-01-02 for swash plate of swash plate type compressor.
Invention is credited to Kato, Takayuki, Mizutani, Hideki, Murakami, Tomohiro, Okubo, Shino, Sugiura, Manabu.
Application Number | 20030000376 10/169440 |
Document ID | / |
Family ID | 26601450 |
Filed Date | 2003-01-02 |
United States Patent
Application |
20030000376 |
Kind Code |
A1 |
Sugiura, Manabu ; et
al. |
January 2, 2003 |
Swash plate of swash plate type compressor
Abstract
A swash plate (15) of a swash plate type compressor includes a
slide-contact film (32, 33) having a metal layer, which is formed
on a slide-contact surface (152, 153), which slide-contacts shoes
(18), through sintering, and a resin layer (322, 332), which is
formed on the metal layer. By using the metal layer, which is
formed through sintering, the bonding of the resin layer and the
metal layer is guaranteed, deficiencies such as cracking of a slide
film and seizure are prevented, and the slide-contact
characteristic relative to the shoes is improved.
Inventors: |
Sugiura, Manabu;
(Kariya-shi, JP) ; Kato, Takayuki; (Kariya-shi,
JP) ; Mizutani, Hideki; (Kariya-shi, JP) ;
Okubo, Shino; (Kariya-shi, JP) ; Murakami,
Tomohiro; (Kariya-shi, JP) |
Correspondence
Address: |
Kurt E Richter
Morgan & Finnegan
345 Park Avenue
New York
NY
10154
US
|
Family ID: |
26601450 |
Appl. No.: |
10/169440 |
Filed: |
June 28, 2002 |
PCT Filed: |
October 1, 2001 |
PCT NO: |
PCT/JP01/08651 |
Current U.S.
Class: |
92/70 |
Current CPC
Class: |
F04B 27/1054 20130101;
F05C 2201/021 20130101; F05C 2253/12 20130101; F05C 2201/0475
20130101; F05C 2251/14 20130101 |
Class at
Publication: |
92/70 |
International
Class: |
F01B 003/00 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 3, 2000 |
JP |
2000-303558 |
Apr 20, 2001 |
JP |
2001-123037 |
Claims
1. A swash plate (15) of a swash plate type compressor that
transmits the rotating force of the swash plate, which rotates
integrally with a rotary shaft (13), to a piston (17) by means of a
shoe (18) to reciprocally move the piston, wherein the swash plate
rotates while slide-contact occurs between the shoe and a
slide-contact surface (152, 153), the swash plate comprising: a
slide-contact film including a metal layer (321, 331), which is
formed on the slide-contact surface of the swash plate through
sintering, and a resin layer (322, 332) or a plating layer, which
is formed on the metal layer.
2. The swash plate according to claim 1, wherein the metal layer is
made of a copper material or an aluminum material.
3. The swash plate according to claim 1 or 2, wherein the resin
layer or the plating layer includes a solid lubricant.
4. The swash plate according to any one of claims 1 to 3, wherein
the metal layer has a surface that is not ground, and the resin
layer or the plating layer is formed on the surface.
5. The swash plate according to any one of claims 1 to 4, wherein
the swash plate is made of a steel material.
6. A swash plate type compressor including: a rotary shaft (13); a
swash plate (15) rotated integrally with the rotary shaft; a shoe
(18) that slidably contacts a slide-contact surface of the swash
plate (15) when the swash plate rotates; and a piston (17)
connected to swash plate by means of the shoe, the swash plate
comprising: a slide-contact film including a metal layer (321,
331), which is formed on the slide-contact surface of the swash
plate through sintering, and a resin layer (322, 332) or a plating
layer, which is formed on the metal layer.
7. The swash plate type compressor according to claim 6, wherein
the metal layer is made of a copper material or an aluminum
material.
8. The swash plate type compressor according to claim 6 or 7,
wherein the resin layer or the plating layer includes a solid
lubricant.
Description
TECHNICAL FIELD
[0001] The present invention relates to a swash plate type
compressor, and more particularly, to a swash plate having a
surface, which contacts shoes, with a slide-contact film formed
thereon in a swash plate type compressor that transmits the
rotational force of the swash plate to pistons by means of shoes to
reciprocally move the pistons.
BACKGROUND ART
[0002] As disclosed in Japanese Laid-Open Patent Publication No.
2-267371, pistons of a swash plate type compressor are reciprocally
moved by the rotating action of a swash plate, which rotates
integrally with a rotary shaft. Shoes are arranged between the
peripheral portion of the swash plate and the pistons. The
rotational force of the swash plate is transmitted to the pistons
by means of the shoes. The shoes, which are made of a steel
material, contact the rotating swash plate. Thus, the slide-contact
portion between the shoes and the swash plate may wear out, and
seizure may occur between the shoes and the swash plate. The
slide-contact characteristic of the swash plate with respect to the
shoes must therefore be improved. Japanese Laid-Open Patent
Publication No. 2-267371 discloses a swash plate having a metal
layer formed on the surface of the swash plate that comes into
contact with the shoes. The metal layer is formed by sintering or
spraying a copper bearing alloy.
[0003] However, the metal layer, which is formed by spraying the
copper bearing alloy, may result in the occurrence of deficiencies,
such as cracking of the slide-contact film or seizure. Accordingly,
Japanese Laid-Open Patent Publication No. 2-267371 discloses a
swash plate having a resin layer, which includes a solid lubricant,
formed on the metal layer by spraying copper. Further, the
formation of a plating layer on the metal layer has been proposed
in the prior art. The resin layer, which is formed by means of
spraying, or the plating layer contribute to preventing cracking of
the slide-contact film or seizure but do not obtain desirable
results from the viewpoint of slide-contact (sliding)
characteristic with respect to the shoes.
DISCLOSURE OF THE INVENTION
[0004] It is an object of the present invention to provide a swash
plate of a swash plate type compressor that prevents the occurrence
of deficiencies, such as cracking of the slide-contact film or
seizure, while improving the slide-contact characteristic with
respect to the shoes.
[0005] A first perspective of the present invention provides a
swash plate of a swash plate type compressor that transmits the
rotating force of the swash plate, which rotates integrally with a
rotary shaft, to a piston by means of a shoe to reciprocally move
the piston. The swash plate rotates while contact occurs between
the shoe and a slide-contact surface. The swash plate includes a
slide-contact film having a metal layer, which is formed on the
slide-contact surface of the swash plate through sintering, and a
resin layer or a plating layer, which is formed on the metal
layer.
[0006] A second perspective of the present invention provides a
swash plate type compressor including a rotary shaft, a swash plate
rotated integrally with the rotary shaft, a shoe that contacts a
slide-contact surface of the swash plate when the swash plate
rotates, and a piston connected to swash plate by means of the
shoe. The swash plate includes a slide-contact film having a metal
layer, which is formed on the slide-contact surface of the swash
plate through sintering, and a resin layer or a plating layer,
which is formed on the metal layer.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1(a) is a cross-sectional side view of a swash plate
type compressor according to an embodiment of the present
invention, and FIG. 1(b) is an enlarged cross-sectional view
showing the main portion of the compressor of FIG. 1(a).
[0008] FIG. 2(a) is a front view showing a swash plate having a
surface on which a metal layer is partially formed, and FIG. 2(b)
is a front view showing the swash plate with a resin layer formed
on the surface of the metal layer.
[0009] FIG. 3 is a side view showing an apparatus for forming the
metal layer.
BEST MODE OF CARRYING OUT THE INVENTION
[0010] A variable displacement compressor according to an
embodiment of the present invention will now be discussed with
reference to FIGS. 1 to 3.
[0011] FIG. 1(a) shows the internal structure of the variable
displacement compressor. The variable displacement compressor
includes a front housing 12, which defines a control pressure
chamber 121, and a cylinder block 11. A rotary shaft 13 is
supported in the housings 11, 12. The rotary shaft 13 is rotated by
drive force, which is transmitted from an external drive source
(e.g., vehicle engine). A circular rotary support 14 is secured to
the rotary shaft 13 to support a circular swash plate 15 so that
the swash plate 15 is slidable and inclinable in the axial
direction of the rotary shaft 13.
[0012] A support body 151 is formed integrally with the swash plate
15, which is made of a steel material. Guide pins 16 are attached
to the support body 151. The guide pins 16 are slidably fitted in
guide holes 141, which are formed in the rotary support 14. The
swash plate 15 is inclinable in the axial direction of the rotary
shaft 13 and integrally rotatable with the rotary shaft 13 by the
cooperation between the guide holes 141 and the guide pins 16. The
inclination of the swash plate 15 is guided by the slide-guide
relationship between the guide holes 141 and the guide pins 16, and
the slide support function of the rotary shaft 13.
[0013] The inclination angle of the swash plate 15 is changed by
controlling the pressure of the control pressure chamber 121. As
the pressure in the control pressure chamber 121 increases, the
inclination angle of the swash plate 15 decreases. As the pressure
in the control pressure chamber 121 decreases, the inclination
angle of the swash plate 15 increases. Refrigerant flows from the
control pressure chamber 121 via a pressure releasing passage,
which is not shown, to a suction chamber 191, which is formed in a
rear housing 19. Further, refrigerant is supplied from a discharge
chamber 192, which is formed in the rear housing 19, to the control
pressure chamber 121 via a pressure supply passage, which is not
shown.
[0014] A displacement control valve 25 is arranged in the pressure
supply passage. The flow rate of the refrigerant supplied from the
discharge chamber 192 to the control pressure chamber 121 is
controlled by the displacement control valve 25. When the flow rate
of the refrigerant supplied from the discharge chamber 192 to the
control pressure chamber 121 increases, the pressure in the control
pressure chamber 121 increases. When the flow rate of the
refrigerant supplied from the discharge chamber 192 to the control
pressure chamber 121 decreases, the pressure in the control
pressure chamber 121 decreases. Accordingly, the inclination angle
of the swash plate 15 is controlled by the displacement control
valve 25.
[0015] The maximum inclination angle of the swash plate 15 is
determined by the contact between the swash plate 15 and the rotary
support 14. The minimum inclination angle of the swash plate 15 is
determined by the contact between a snap ring 24 on the rotary
shaft 13 and the swash plate 15.
[0016] A plurality of cylinder bores 111 (only two shown in FIG.
1(a)) are arranged about the rotary shaft 13 in the cylinder block
11. A piston 17 is retained in each cylinder bore 111. A holding
portion 171 is formed in one end of the piston 17. A pair of
opposed spherical recess portions 172, 173 are formed in the
holding portion 171. As shown in FIG. 1(b), semispherical shoes 18
are held in the recess portions 172, 173 not to be spilled
therefrom.
[0017] The rotating action of the swash plate 15, which rotates
integrally with the rotary shaft 13, is converted to the forward
and rearward reciprocating action of the piston 17 by the
semispherical shoes 18 to move the piston 17 forward and rearward
in the cylinder bore 111. The pair of shoes 18 are made of a steel
material and slidably contact slide-contact surfaces 30, 31 of the
swash plate 15.
[0018] The reciprocating movement of the pistons 17 (movement from
the right to the left, as viewed in FIG. 1(a)) causes the
refrigerant in the suction chamber 191 to open suction valves 211,
which are formed in a valve formation plate 21, and flow into the
cylinder bores 111 through suction ports 201, which are formed in a
valve plate 20. The reciprocating movement of the pistons 17
(movement from the left to the right, as viewed in FIG. 1(a))
causes the refrigerant that entered the cylinder bores 111 to open
discharge valves 221, which are formed in a valve formation plate
22, and flow into the discharge chamber 192 through discharge ports
202, which are formed in the valve plate 20. The discharge valves
221 contact retainers 231, which are formed on a retainer formation
plate 23, so that its opened degree is restricted.
[0019] The discharge chamber 192 and the suction chamber 191 are
connected to each other by an external refrigerant circuit 26. The
refrigerant sent to the external refrigerant circuit 26 from the
discharge chamber 192 flows through a condenser 27, an expansion
valve 28, and an evaporator 29 and returns to the suction chamber
191.
[0020] As shown in FIGS. 1(a) and 1(b), slide-contact films 32, 33
are formed on a front surface 152 and a rear surface 153 of the
peripheral portion of the swash plate 15. The slide-contact film 32
has a double-layer structure comprising a metal layer 321, which is
formed, through sintering, on the front surface (slide-contact
surface) 152 that has a slide-contact section corresponding with
the shoes 18, and a resin layer 322, which is formed on the metal
layer 321. The slide-contact film 33 has a double-layer structure
comprising a metal layer 331, which is formed, through sintering,
on the rear surface (slide-contact surface) 153 that has a
slide-contact section corresponding with the shoes 18, and a resin
layer 332, which is formed on the metal layer 331.
[0021] The metal layers 321, 331 respectively formed on the front
surface 152 and the rear surface 153, which originally are the
surfaces of substrate of the swash plate 15, are formed from a
copper material. The resin layer 322 is made of a material obtained
by dispersing a solid lubricant in resin. In the present
embodiment, molybdenum disulfide and graphite are used as the solid
lubricant, and thermosetting polyamide imide is used as the
resin.
[0022] The metal layers 321, 331 are formed using the apparatus
shown in FIG. 3. The swash plate 15 is attached to a rotary holding
mechanism 35, which is rotated by a motor 34 in the direction of
arrow Q1. Fine copper particles are deposited on the front surface
152 of the peripheral portion of the swash plate 15, which is
attached to the rotary holding mechanism 35, to form a layer that
is greater than or equal to a predetermined thickness.
[0023] In FIG. 2(a), S1 denotes the layer of fine particles
deposited on the front surface 152. A roller 37, which is attached
to an output shaft 361 of the motor 36, is moved reciprocally in
directions of arrow Q2 (vertical direction) by a space maintaining
mechanism 38. The roller 37 has the form of a truncated cone. The
roller 37 is arranged so that its rotating axis extends through the
swash plate 15 near the center P of the swash plate 15 and the
minimum space between the conical surface of the roller 37 and the
front surface 152 of the swash plate 15 is equal to the
predetermined thickness. The motors 34, 36 are synchronously
rotated, and the roller 37 rolls along the front surface 152 of the
swash plate 15 in the circumferential direction of the swash plate
15 without being relatively displaced. That is, the layer of copper
particles on the front surface 152 is pressed by the roller 37 so
that it has the predetermined thickness. The layer of copper
particles having the predetermined thickness is sintered in an
oxygen-free state to form the metal layer 321. The thickness
adjustment by the roller 37 and the sintering treatment is also
performed on the rear surface 153 of the swash plate 15 to form the
metal layer 331.
[0024] Then, a fluid resin coating, which includes a solid
lubricant, is applied to the surface of the metal layers 321, 331.
In FIG. 2(b), S2 denotes a coating film of the resin coating. After
drying the coating film S2, the coating film S2 is baked and
hardened at 200.degree. C. to 300.degree. C. to form the resin
layers 322, 332.
[0025] The variable displacement compressor has the advantages
described below.
[0026] (1) Layers of copper metal particles are formed on the front
and rear surfaces 152, 153 of the swash plate 15, and the layers
are sintered to form intended surface with fine pits and lands in
the surfaces of the metal layers 321, 331. The fluid resin coating,
which includes a solid lubricant, enters the pits of the surface.
Accordingly, the contact area of the metal layers 321, 331 relative
to the resin coating of the sintered surface is greater than the
contact area of a surface that does not have the pits and lands
relative to the resin coating. That is, the bonding capacity of the
resin coating relative to the surface of the metal layers 321, 331
is high. The state of the pits and lands in the surface of the
metal layers 321, 331 is affected by the particle diameter of the
metal particles. However, the sintered surface of the metal layers
321, 331, in which the particle diameter of the metal particles is
optimally set, has a pit and land state that is preferable as a
bonding subject surface of resin.
[0027] Accordingly, the bonding of the resin layers 322, 332 to the
metal layers 321, 331, which are formed through sintering, is
guaranteed. This obtains the slide-contact films 32, 33, which have
superior slide-contact characteristic with respect to the shoes
18.
[0028] (2) The layer thickness of the metal layers 321, 331 is set
at about 60 .mu.m to 70 .mu.m. The layer thickness is obtained by
adjusting the thickness of the copper particle layers, which are
formed on the front and rear surfaces 152, 153, to the desired
layer thickness of the metal layers 321, 331. The thickness of the
copper particle layers is set by adjusting the position of the
rollers 37 relative to the front and rear surfaces 152, 153 of the
swash plate 15. Such adjustment of the position of roller 37 is
simple. Accordingly, the desired layer thickness of the metal
layers 321, 333 is easily obtained.
[0029] (3) Since the metal layers 321, 331 have the desired layer
thickness subsequent to sintering, the metal layers 321, 331 do not
have to be ground to obtain the desired thickness. The elimination
of the grinding process of the metal layers 321, 331 facilitates
the procedure for forming the slide-contact films 32, 33.
[0030] (4) Even when the sintered surfaces of the metal layers 321,
331 are ground, the bonding capacity of the resin coatings relative
to the ground surface is high. This is because fine pores are
formed in the metal layers 321, 331, and fine pits are produced in
the ground surface when grinding the surfaces of the metal layers
321, 331. The fluid resin coating, which includes a solid
lubricant, enters the fine pits and increases the contact area of
the ground surfaces of the metal layers 321, 331 relative to the
resin coating.
[0031] (5) In comparison with a metal layer formed through
spraying, the thickness of the resin layer is uniform when applied
on the sintered metal layers 321, 331. A metal layer, which is
formed through spraying, has relatively large pores. When such
large pores are exposed from the surface of the metal layer, the
thickness of the coating layer of the resin coating is not uniform,
and the formation of a slide-contact film having a uniform coating
thickness becomes difficult.
[0032] (6) The swash plate 15 and the shoes 18 are both made of
steel materials. Thus, if the shoes 18 were to come into direct
slide-contact with the front and rear surfaces 152, 153, seizure
would occur at an early stage. The same type of materials is an
inadequate combination from the viewpoint of seizure when they come
into contact with each other. Even if the shoes 18 come into direct
contact with the metal layers 321, 331, since the metal layers 321,
331 are made of a copper material, which differs from the material
of the shoes 18, seizure is prevented from occurring at an early
stage.
[0033] (7) A mixture of solid lubricant and resin is effective for
improving the slide-contact characteristic of a slide-contact film,
which includes a metal layer. Particularly, the mixture of
molybdenum disulfide, graphite, and polyamide imide is extremely
effective for improving the contact characteristic of the
slide-contact films 32, 33.
[0034] (8) The front and rear surfaces 152, 153 of the swash plate
15 are flat and are thus preferable for uniformly depositing the
layers of metal particles with the desired thickness.
[0035] The present invention may be embodied in the following forms
without departing from the scope of the present invention.
[0036] The resin layers may be altered to plating layers. The same
effects as advantage (1) in the above embodiment guarantees the
bonding of the metal layers 321, 331, which are formed through
sintering, with the plating layers. For example, a nickel plating
or a cobalt plating may be given as the types of plating, and
electroplating, chemical plating, or electroless plating may be
given as the types of plating processes. In this case, if a
composite plating, which disperses a solid lubricant in the
plating, is formed, the slide-contact characteristic between a
swash plate and shoes is further improved.
[0037] In addition to molybdenum disulfide and graphite, which are
discussed above, tungsten disulfide, boron nitride, antimony oxide,
indium, tin, and so forth may be used as the solid lubricant.
[0038] A double-layer structure including a first metal layer,
which has a relative small particle diameter, and a second metal
layer, which has a relatively large particle diameter, may be
formed, and a resin layer may be formed on the second metal layer
to form a slide-contact film. The fine pits and lands in the
surface of the second metal layer increase the bonding capacity of
a resin layer. The metal layers of such double-layer structure is
obtained by depositing metal particles having a relatively small
particle diameter on the peripheral surface of the swash plate to a
predetermined thickness to form a first deposit layer, then
depositing metal particles having a relatively large particle
diameter on the first deposit layer to a predetermined thickness to
form a second deposit layer, and then sintering the first and
second deposit layers. The sintering simultaneously forms two metal
layers.
[0039] An aluminum material may be formed for the metal layers.
[0040] When forming the metal layers of the double-layer structure
with aluminum that includes silicon, it is preferred that the
silicon content of the first metal layer, which is formed on the
surface of the swash plate, be small and that the silicon content
of the second metal layer, to which a resin layer is applied, be
large. When the silicon content is small, the bonding strength of
the first metal layer with respect to the surface of the swash
plate is large. When the silicon content is increased, the contact
characteristic of the second metal layer, to which the resin layer
is applied, is improved.
[0041] The present invention may be applied to a swash plate made
of an aluminum material to reduce weight.
[0042] The present invention may be applied to a swash plate of a
fixed displacement swash plate type compressor.
* * * * *