FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION
[See section 10, Rule 13]
COMPRESSOR AND REFRIGERATION CYCLE APPARATUS;
MITSUBISHI ELECTRIC CORPORATION, A CORPORATION
ORGANISED AND EXISTING UNDER THE LAWS OF JAPAN, WHOSE ADDRESS
IS 7-3, MARUNOUCHI 2-CHOME, CHIYODA-KU, TOKYO 1008310, JAPAN
THE FOLLOWING SPECIFICATION PARTICULARLY DESCRIBES THE INVENTION
AND THE MANNER IN WHICH IT IS TO BE PERFORMED

2
DESCRIPTION
Technical Field
5 [0001]
The present disclosure relates to a compressor that has a discharge
mechanism by which refrigerant is discharged and a refrigeration cycle apparatus.
Background Art
[0002]
10 Some compressor has been present in which a valve body is located in a
discharge outlet when the discharge outlet is closed and the valve body is
reciprocated by a spring to reduce dead volume. Refer, for example, to Patent
Literature 1.
Citation List
15 Patent Literature
[0003]
Patent Literature 1: Japanese Unexamined Patent Application Publication No.
8-319973
Summary of Invention
20 Technical Problem
[0004]
In some compressor, a valve body is located in a discharge outlet and the valve
body is reciprocated by a spring. In this case, the valve body is in contact with a wall
face of the discharge outlet and jamming is thus caused. When jamming occurs, the
25 valve body is worn down. When the valve body is worn down, improper closure at a
compression chamber may reduce efficiency of the compressor and cause a
breakdown in the compressor.
[0005]
The present disclosure is made to avoid such inconvenience, and an object of
30 the present disclosure is to provide a compressor and a refrigeration cycle apparatus

3
in which jamming is less likely to be caused around a valve body to improve efficiency
of the compressor and prevent a breakdown in the compressor.
Solution to Problem
[0006]
5 A compressor according to an embodiment of the present disclosure has an
airtight container; a cylinder provided in the airtight container and in which a
compression chamber is provided in which refrigerant is compressed; a main shaft
provided in the airtight container; a shaft bearing provided to the main shaft and to
which a discharge outlet is provided through which refrigerant compressed in the
10 compression chamber is discharged; and a discharge mechanism that has a guide lid
that is provided to the shaft bearing and has a guide hole in the guide lid and a valve
body provided in the guide hole and is configured to open and close the discharge
outlet when the valve body moves in the guide hole, in which the guide lid has a
communication hole through which the guide hole and an inside of the airtight
15 container into which refrigerant discharged from the discharge outlet is discharged
communicate with each other, and, to the communication hole, refrigerating machine
oil that remains in the airtight container is supplied.
Advantageous Effects of Invention
[0007]
20 According to an embodiment of the present disclosure, the guide lid has the
communication hole, through which the guide hole and the inside of the airtight
container into which refrigerant discharged from the discharge outlet is discharged
communicate with each other. To the communication hole, refrigerating machine oil
is supplied. The valve body is configured to open and close the discharge outlet by
25 moving in the guide hole. The refrigerating machine oil supplied to the
communication hole passes through the guide hole and flows through a gap between
the valve body and the side face of the guide hole. The compressor is therefore
configured such that jamming is less likely to be caused around the valve body and
thus to improve efficiency of the compressor and prevent a breakdown in the
30 compressor.

4
Brief Description of Drawings
[0008]
[Fig. 1] Fig. 1 is a schematic configuration diagram that schematically illustrates
a configuration of a compressor according to Embodiment 1.
5 [Fig. 2] Fig. 2 is a diagram that illustrates a state in which a valve body in a
discharge mechanism in the compressor according to Embodiment 1 closes a
discharge outlet.
[Fig. 3] Fig. 3 is a diagram that illustrates a state in which the valve body in the
discharge mechanism in the compressor according to Embodiment 1 opens the
10 discharge outlet.
[Fig. 4] Fig. 4 is a diagram that illustrates a method of oil supply to a
communication hole in the discharge mechanism in the compressor according to
Embodiment 2.
[Fig. 5] Fig. 5 is a diagram that illustrates a method of oil supply to the
15 communication hole in the discharge mechanism in the compressor according to
Embodiment 3.
[Fig. 6] Fig. 6 is a diagram that illustrates an oil-supply groove that is linearshaped and is provided to the discharge mechanism in the compressor according to
Embodiment 4.
20 [Fig. 7] Fig. 7 is a diagram that illustrates an oil-supply groove that is spiralshaped and is provided to the discharge mechanism in the compressor according to
Embodiment 4.
[Fig. 8] Fig. 8 is a refrigerant circuit diagram that schematically illustrates a
configuration of a refrigerant circuit in a refrigeration cycle apparatus according to
25 Embodiment 5.
[Fig. 9] Fig. 9 is a chart that illustrates gas density in refrigerant sucked in the
compressor and gas density in refrigerant discharged from the compressor under
rated conditions of compressor operation in a typical refrigeration cycle stipulated in
ASHRAE.
30 [Fig. 10] Fig. 10 is a diagram that illustrates an example of a reed valve in a

5
compressor.
[Fig. 11] Fig. 11 is a diagram that illustrates a lift distance of the valve body in
the compressor used in the refrigeration cycle apparatus according to Embodiment 6.
Description of Embodiments
5 [0009]
A compressor according to embodiments is described below with reference to
drawings. In the drawings, the same components are described by use of the same
reference signs and not described again unless necessary. The present disclosure
may include any combination of configurations that are combinable with each other
10 among configurations described below in respective embodiments. In addition, a
relationship in size between components in the drawings may differ from actual one.
The form of components represented in the entire specification is merely an example,
and does not limit the components to the form described in the specification. In
particular, a combination of components is not limited only to that in each embodiment.
15 A component described in one embodiment may be applied to another embodiment.
In addition, pressure levels and temperature levels are not determined in relation to
particular absolute values but are relatively determined under conditions, such as
states and operation of devices. In addition, in the following description, the
longitudinal direction of an airtight container, which is an up-down direction in the
20 drawings, is defined as an axial direction. Also, a direction that passes through the
center axis in the airtight container and is perpendicular to the center axis is defined
as a radial direction.
[0010]
Embodiment 1
25 Fig. 1 is a schematic configuration diagram that schematically illustrates a
configuration of a compressor 100 according to Embodiment 1.
[0011]
The compressor 100 is described below with reference to Fig. 1. The
compressor 100 is to serve as a component in a refrigerant circuit in a refrigeration
30 cycle apparatus, such as a refrigerator, a freezer, a vending machine, an air-

6
conditioning apparatus, a refrigeration apparatus, and a water heater. Fig. 1
illustrates a rotary compressor as an example of the compressor 100. The
compressor 100 is also applicable to a scroll compressor, a reciprocating compressor,
or other airtight compressor that has a discharge valve. In addition, fluid to be
5 compressed by the compressor 100 is here described as refrigerant used in an
apparatus such as a refrigeration cycle apparatus.
[0012]
[Configuration of Compressor 100]
The compressor 100 is configured to compress sucked refrigerant and
10 discharge the refrigerant. The compressor 100 has an airtight container 3. The
airtight container 3 is formed by a lower container 1 and an upper container 2. The
airtight container 3 houses a compression mechanism unit 10 and a motor unit 20.
For example, Fig. 1 illustrates a state, as an example, in which the compression
mechanism unit 10 is housed in a lower portion of the airtight container 3 and the
15 motor unit 20 is housed in an upper portion of the airtight container 3. Also, a bottom
portion of the airtight container 3 serves as an oil reservoir in which refrigerating
machine oil is pooled. Refrigerating machine oil mainly lubricates sliding portions in
the compression mechanism unit 10.
[0013]
20 To the lower container 1 of the airtight container 3, a first suction pipe 31a and
a second suction pipe 31b, which communicate with an accumulator 300, which is
referable to Fig. 8, are connected. Respective inlet ports of the first suction pipe 31a
and the second suction pipe 31b are inserted into a suction muffler 60. The suction
inlet 50 of the first suction pipe 31a is formed at a cylinder 13. For the second
25 suction pipe 31b, a configuration similar to the configuration of the first suction pipe
31a is also used. Such a configuration of the second suction pipe 31b is formed at
another cylinder. The suction muffler 60 is connected to the accumulator 300
through a portion of a low-pressure pipe 155b, which is referable to Fig. 8, in a
refrigeration cycle circuit and refrigerant flows from the accumulator 300 into the
30 suction muffler 60. The suction muffler 60 is fixed to the outer circumference of the

7
airtight container 3. The compressor 100 draws refrigerant, which is gas refrigerant,
into the airtight container 3 from the accumulator 300 through the first suction pipe
31a and the second suction pipe 31b. At an upper portion of the upper container 2
of the airtight container 3, a discharge pipe 2a is connected. The compressor 100
5 discharges refrigerant compressed in the compression mechanism unit 10 to the
outside through the discharge pipe 2a. The accumulator 300 is described later.
[0014]

The compression mechanism unit 10 is configured to compress refrigerant by being
10 driven by the motor unit 20.
[0015]
The compression mechanism unit 10 is configured such that the cylinder 13, a
rolling piston 16, a shaft bearing 14, a main shaft 11, and an unillustrated vane are
included.
15 [0016]
The cylinder 13 is located in the airtight container 3, is substantially circularshaped in plan view at its outer circumference, and has a compression chamber 30,
which is a substantially circular-shaped space in plan view, in the inside of the
cylinder 13. The cylinder 13 has a specified height in the axial direction in side view.
20 The compression chamber 30 has open ends opposite to each other in the axial
direction. Also, to the cylinder 13, an unillustrated vane groove that communicates
with the compression chamber 30 and extends in a radial direction is provided such
that the vane groove extends through the cylinder 13 in the axial direction. The
compression chamber 30 in the cylinder 13 is a space defined by attaching the shaft
25 bearing 14 to one end of the cylinder 13, which is cylindrical, in a direction in which
the main shaft 11 extends and by attaching a partition plate 15 to the other end. In
the compression chamber 30, refrigerant is compressed.
[0017]
To the cylinder 13, an unillustrated suction port through which gas refrigerant
30 sucked through the first suction pipe 31a passes is also provided. The suction port

8
is formed such that the suction port extends through from the outer-circumferential
face of the cylinder 13 to the compression chamber 30.
[0018]
Also, to the cylinder 13, an unillustrated discharge port through which
5 refrigerant compressed in the compression chamber 30 is discharged from the
compression chamber 30 is also provided. The discharge port is formed by cutting a
portion of an edge portion of an upper end face of the cylinder 13.
[0019]
The rolling piston 16 is ring-shaped and housed in the compression chamber
10 30 such that the rolling piston 16 is eccentrically rotatable. The rolling piston 16 is
also fitted to, at its inner circumference portion, an eccentric shaft portion 12 of the
main shaft 11 such that the rolling piston 16 is slidable.
[0020]
In the unillustrated vane groove, a vane is housed. By an unillustrated vane
15 spring provided to a back-pressure chamber, the vane housed in the vane groove is
always pressed against the rolling piston 16. When the pressure in the airtight
container 3 is high and the compressor 100 start operation, on the back-pressure
chamber, which is located in the rear face of the vane, force caused by differential
pressure between high pressure in the airtight container 3 and pressure in the
20 compression chamber 30 acts. The vane spring is thus used, mainly when the
compressor 100 starts with no pressure difference between the inside of the airtight
container 3 and the inside of the compression chamber 30, to press the vane against
the rolling piston 16.
[0021]
25 The shape of the vane is a substantial cuboid. Specifically, the vane is a
substantial cuboid that is flat such that its circumferential length, which is also referred
to as thickness, is smaller than each of its radial length and its axial length.
[0022]
The shaft bearing 14 is located in the airtight container 3 and substantially
30 inverted T-shaped in side view. The shaft bearing 14 is fitted to a main shaft portion

9
11a of the main shaft 11, which is a portion upper than the eccentric shaft portion 12,
such that the main shaft 11 is slidable. The shaft bearing 14 closes one end face of
the compression chamber 30 and its vicinity that includes the vane groove of the
cylinder 13, which is an end face that faces toward the motor unit 20. To the shaft
5 bearing 14, a discharge outlet 45, which is referable to Fig. 2, is also provided. The
discharge outlet 45 is provided to a flange portion of the shaft bearing 14 such that
the compression chamber 30 and the airtight container 3 communicate with each
other. The discharge outlet 45 is a hole that forms a passage through which
refrigerant passes when the refrigerant is discharged from the compression chamber
10 30 into the airtight container 3. An opening portion of the discharge outlet 45 that
faces toward the compression chamber 30 is located at an end face of the
compression chamber 30. Specifically, the opening portion of the discharge outlet
45 that faces toward the compression chamber 30 is formed such that the positions of
the opening portion and an upper face of the compression chamber 30 defined in the
15 cylinder 13 substantially coincide with each other in plan view. To an inside and
upper portion of the shaft bearing 14, a discharge mechanism 40, which has a valve
body 41, which is referable to Fig. 2 and Fig. 3, is provided. The configuration of the
discharge mechanism 40 is described later. The discharge mechanism 40 for the
cylinder 13 at which the second suction pipe 31b is located may be located at a shaft
20 bearing 14a, which is lower than the shaft bearing 14.
[0023]
The valve body 41 is configured to open and close the discharge outlet 45 by
receiving pressure in the compression chamber 30 and pressure in the airtight
container 3. When the pressure in the compression chamber 30 is lower than the
25 pressure in the airtight container 3, the valve body 41 is pressed against the
discharge port and the discharge outlet 45 is closed. The valve body 41 is located
such that, when the valve body 41 closes the discharge outlet 45, an end face of the
valve body 41 that faces toward the compression chamber 30 is almost even with an
end face of the discharge outlet 45 that faces toward the compression chamber 30.
30 The end face of the compression chamber 30 and the end face of the valve body 41

10
that faces toward the compression chamber 30 thus coincide with each other at the
same plane. In other words, the valve body 41 closes an opening face of the
discharge outlet 45 that faces toward the compression chamber 30 from the inside of
the discharge outlet 45. The above expression "coincide with each other" includes a
5 case in which, to secure clearance, for example, the end face of the valve body 41
that faces toward the compression chamber 30 is only away from the corresponding
end of the discharge outlet 45 by a slight distance. For example, such a case may
be a case in which the end face of the valve body 41 that faces toward the
compression chamber 30 and the corresponding end face of the compression
10 chamber 30 are only away from each other by a distance of approximately one tenth
of a whole length of the discharge outlet 45. To increase an area at which pressure
from the compression chamber 30 is received, a dent, a groove, and other shape may
also be formed in the valve body 41 at a portion of the valve body 41 that faces
toward the compression chamber 30.
15 [0024]
On the other hand, when the pressure in the compression chamber 30 is higher
than the pressure in the airtight container 3, the valve body 41 is pushed upward by
the pressure in the compression chamber 30 and thus releases the discharge outlet
45. When the discharge outlet 45 is released, refrigerant compressed in the
20 compression chamber 30 is guided to the outside of the compression chamber 30.
[0025]
When the discharge outlet 45 opens, high-temperature and high-pressure gas
refrigerant discharged from the discharge outlet 45 is emitted into the airtight
container 3.
25 [0026]
The valve body 41 is, for example, round-columnar-shaped such that its outer
diameter Φ is 20 [mm] and its height is 16 [mm].
[0027]
The suction muffler 60 is located next to the airtight container 3. The suction
30 muffler 60 sucks low-pressure gas refrigerant from a refrigeration cycle. The suction

11
muffler 60 prevents, in a case in which liquid refrigerant returns from the refrigeration
cycle, the liquid refrigerant from being sucked directly into the compression chamber
30 in the cylinder 13. The suction muffler 60 is connected to the suction ports in the
cylinder 13 through the first suction pipe 31a and the second suction pipe 31b. The
5 suction muffler 60 is fixed to the side face of the airtight container 3 by welding or
other method.
[0028]
High-temperature and high-pressure gas refrigerant compressed in the
compression mechanism unit 10 passes through the motor unit 20 from the discharge
10 outlet 45 located inside the discharge muffler 17, which is referable to Fig. 2, and is
discharged through the discharge pipe 2a to the outside of the compressor 100.
[0029]

The motor unit 20 is configured to drive the compression mechanism unit 10.
15 [0030]
The motor unit 20 is configured such that a rotor 21, a stator 22, and other
components are included. The stator 22 is in contact with and fixed to the inner
circumferential face of the airtight container 3. The rotor 21 is located in the inside of
the stator 22 with a gap between the rotor 21 and the stator 22.
20 [0031]
The stator 22 has at least a stator core of which a plurality of magnetic steel
sheets are laminated and a winding wire wound around teeth of the stator core by
concentrated winding with an insulator component between the winding wire and the
teeth. To the winding wire of the stator 22, a lead wire is also connected. The lead
25 wire is connected to a glass terminal provided to the upper container 2 to supply
electric power from the outside of the airtight container 3.
[0032]
The rotor 21 has at least a rotor core of which a plurality of magnetic steel
sheets are laminated and a permanent magnet inserted into the rotor core. To the
30 center of the rotor core, the main shaft portion 11a of the main shaft 11 is shrink-fitted

12
or press-fitted. To the lowermost end of the main shaft 11, which rotates by the
motor unit 20, an oil-supply pump 70 is provided. The oil-supply pump 70 draws, by
centrifugal force produced by rotation of the main shaft 11, refrigerating machine oil
that remains in the airtight container 3, which is located at the distal end of the oil5 supply pump 70, and raises the refrigerating machine oil by the centrifugal force.
The refrigerating machine oil drawn and raised in the inside of the main shaft 11 is
supplied to the discharge mechanism 40 through an oil-supply hole 11_1 of the main
shaft 11, which is referable to Fig. 4 and is provided through portions of the main shaft
11. To the discharge muffler 17, the refrigerating machine oil drawn by the oil-supply
10 pump 70 into the main shaft 11 is also supplied.
[0033]

Fig. 2 is a diagram that illustrates a state in which the valve body 41 in the discharge
mechanism 40 in the compressor 100 according to Embodiment 1 closes the
15 discharge outlet 45. Fig. 3 is a diagram that illustrates a state in which the valve
body 41 in the discharge mechanism 40 in the compressor 100 according to
Embodiment 1 opens the discharge outlet 45. As illustrated in Fig. 2 and Fig. 3, the
discharge mechanism 40 has the valve body 41, a spring 43, and a guide lid 46. An
arrow illustrated in Fig. 2 indicates high-pressure gas refrigerant of which pressure is
20 applied from the compression chamber 30 to the valve body 41. Also, arrows
illustrated in Fig. 3 indicate courses through which high-pressure gas refrigerant flow.
[0034]
The guide lid 46 is cylindrical and has a closure portion 46a, which is provided
close to an upper portion of the shaft bearing 14, and a cylindrical portion 46b, which
25 is provided inside of the shaft bearing 14. The inside of the closure portion 46a and
the inside of the cylindrical portion 46b define a guide hole 42. The closure portion
46a is a portion of the guide lid 46 at which a communication hole 44 is provided.
The cylindrical portion 46b is a portion of the guide lid 46 that faces toward a portion
at which the compression chamber 30 is located. The cylindrical portion 46b is
30 located in the shaft bearing 14. The inside of the cylindrical portion 46b and the

13
discharge outlet 45 communicate with each other. The lowermost end of the
cylindrical portion 46b is formed such that the lowermost end fits on the shape of the
valve body 41. To the lowermost end of the cylindrical portion 46b, a valve-body
seat portion 46c formed in the shaft bearing 14 is provided. The valve-body seat
5 portion 46c is chamfered. A face is chamfered by, for example, 2 [mm] in its height
direction and 3 [mm] in its radial direction.
[0035]
The closure portion 46a and the cylindrical portion 46b of the guide lid 46 are
formed integrally with each other. The closure portion 46a and the cylindrical portion
10 46b, however, may also be formed as parts separated from each other. Also, the
cylindrical portion 46b of the guide lid 46, which is formed as a part separated from
the shaft bearing 14, may also be formed integrally with the shaft bearing 14. The
shaft bearing 14, the closure portion 46a, and the cylindrical portion 46b are formed
into two parts or three parts. To the closure portion 46a of the guide lid 46, one end
15 of the spring 43, which is a connection component, is attached. The one end of the
spring 43 is located in the guide hole 42 in the guide lid 46. The other end of the
spring 43 is attached to the valve body 41. The spring 43 applies spring force, which
is elastic force, in a direction in which the valve body 41 closes the discharge outlet
45.
20 [0036]
The guide hole 42 is a round-columnar-shaped space and is the inside of the
closure portion 46a of the guide lid 46 and the inside of the cylindrical portion 46b of
the guide lid 46. Also, the cylindrical portion 46b is located in a hole provided to the
flange portion of the shaft bearing 14. One end of the guide hole 42 that faces
25 toward the compression chamber 30 is formed such that the one end coincides with
the corresponding end face of the compression chamber 30 and fits on the inside wall
of the cylinder 13. Also, a lower portion of the shaft bearing 14 coincides with the
corresponding end face of the compression chamber 30 and the corresponding end
face of the cylinder 13. Also, a space inside the guide lid 46 may also be formed by
30 tooling from the side face of the flange portion of the shaft bearing 14. The guide

14
hole 42 may also be formed by providing a fixation portion on the upper face of the
flange portion of the shaft bearing 14 and by covering the fixation portion with a
component that has a flat face that defines the guide hole 42. The guide hole 42
may also be formed such that another component covers a flat face at an end portion
5 of the guide hole 42 opposite to the compression chamber 30.
[0037]
A horizontal gap between the side face of the valve body 41 and the side face
of the guide hole 42 is less than 100 [μm].
[0038]
10 The one end of the guide hole 42 that faces toward the compression chamber
30 does not necessarily coincide with the corresponding end face of the compression
chamber 30, which is located under the guide hole 42, and does not necessarily fit on
the inside wall of the cylinder 13. The one end of the guide hole 42 that faces
toward the compression chamber 30 may also be, for example, located outside the
15 inside wall of the cylinder 13. In this case, a portion of the valve body 41 is in
contact with or comes close to the cylinder 13 or is in contact with an object such as
an elastic body provided on the cylinder 13. Also , the one end of the guide hole 42
that faces toward the compression chamber 30 may also be located slightly further
inside the airtight container 3 than is the corresponding end face of the compression
20 chamber 30. Clearance between the valve body 41 and the rolling piston 16 are
thus secured.
[0039]
Also, in a case in which the guide lid 46 is a part separate from the shaft
bearing 14, the guide lid 46 may also be located inside the flange portion of the shaft
25 bearing 14. In this case, the discharge outlet 45 has its reduced length and an
opening portion of the guide hole 42 that faces toward the compression chamber 30
is made to be an opening portion that communicates with the inside of the airtight
container 3. The valve-body seat portion 46c may also be located at the cylindrical
portion 46b of the guide lid 46 rather than at the shaft bearing 14.
30 [0040]

15
The valve body 41 may also be in a state in which, when the discharge outlet
45 opens wide, the distal end of the valve body 41 protrudes slightly into the inside of
the discharge outlet 45 and partially covers the discharge outlet 45. The distal end
of the valve body 41 is thus prevented from entering the inside of the opening port in
5 the side face of the discharge outlet 45.
[0041]
In the closure portion 46a of the guide lid 46, the communication hole 44, which
is round-columnar-shaped, is opened. The communication hole 44 communicates
with the inside of the airtight container 3 to which high-pressure refrigerant discharged
10 through the guide hole 42 in the guide lid 46 and the discharge outlet 45 is discharged
through the discharge muffler 17. The horizontal outer diameter of the
communication hole 44 is smaller than the horizontal outer diameter of the valve body
41. The diameter of the communication hole 44 is smaller than the inner diameter of
the guide lid 46 and is Φ6 mm in this description. The shape of the communication
15 hole 44, which is circular-shaped, may also be selected to be oval-shaped in
consideration of interference with parts around the communication hole 44. The
valve-body seat portion 46c of the guide lid 46 may also be formed such that at least
a portion of a bottom portion of the valve body 41 is exposed.
[0042]
20 The valve body 41 is located in the guide hole 42 and, in a case in which
pressure in the guide hole 42 is higher than pressure in the compression chamber 30,
slides and moves downward along the guide hole 42. The discharge outlet 45 is
thus closed. This state is referable to Fig. 2. When the valve body 41 closes the
discharge outlet 45, the side face of the valve body 41 is in contact with the
25 corresponding portion of the side face of the discharge outlet 45. For this reason, a
portion of the side face of the valve body 41 that faces the discharge outlet 45 is
formed such that the portion of the side face of the valve body 41 that faces the
discharge outlet 45 is not uneven to the side face of the discharge outlet 45. Also, in
a case in which pressure in the guide hole 42 is lower than pressure in the
30 compression chamber 30, the valve body 41 moves upward in the guide hole 42. As

16
illustrated in Fig. 3, the discharge outlet 45 is thus opened.
[0043]
As illustrated in Fig. 2 and Fig. 3, around the discharge mechanism 40, the
discharge muffler 17 is located. The discharge muffler 17 is, when the compressor
5 100 is viewed from above, a part that accounts for a large portion of the airtight
container 3. Refrigerating machine oil that remains at a lower portion of the airtight
container 3 is raised when the compressor 100 operates. Much of the raised
refrigerating machine oil thus remains at an upper portion of the discharge muffler 17.
To an upper portion of the discharge muffler 17, which is above the communication
10 hole 44, an oil-supply hole 17_1 in the discharge muffler 17 is provided. The
refrigerating machine oil that remains in the discharge muffler 17 is supplied from the
oil-supply hole 17_1 in the discharge muffler 17 to the communication hole 44. Oil
supply, which is thus achieved such that refrigerating machine oil drips from the oilsupply hole 17_1 in the discharge muffler 17 onto the communication hole 44, may
15 also be achieved by another method.
[0044]
[Operation of Compressor 100]
Electric power is supplied to the stator 22 in the motor unit 20 through the lead
wire. Electric current thus flows through the winding wire of the stator 22 and
20 magnetic flux is generated from the winding wire. The rotor 21 in the motor unit 20 is
rotated by action caused by magnetic flux generated from the winding wire and
magnetic flux generated from the permanent magnet in the rotor 21. By rotation of
the rotor 21, the main shaft 11, which is fixed to the rotor 21, is rotated. Along with
rotation of the main shaft 11, the rolling piston 16 in the compression mechanism unit
25 10 eccentrically rotates in the compression chamber 30 in the cylinder 13.
[0045]
A space between the cylinder 13 and the rolling piston 16 in the compression
chamber 30 is divided into two by an unillustrated vane. Along with rotation of the
main shaft 11, these two spaces changes their respective capacities. One space of
30 the two spaces gradually increases in capacity and low-pressure gas refrigerant is

17
sucked from the accumulator 300 into the one space. The other space of the two
spaces gradually reduces in capacity and gas refrigerant in the other space is
compressed in the compression chamber 30.
[0046]
5 The gas refrigerant compressed in the compression chamber 30 into a highpressure and high-temperature state pushes up the valve body 41 in the discharge
mechanism 40 and is discharged from the discharge outlet 45. The unillustrated
vane is pressed against the rolling piston 16 by high-pressure refrigerant emitted into
the airtight container 3. Along movement of the rolling piston 16, the vane radially
10 slides in the vane groove in a radial direction and serves such that the vane partitions
the space in the compression chamber 30 into a low-pressure space and a highpressure space. At this time, the discharge mechanism 40 is caused, by a pressure
difference between discharge pressure in the airtight container 3 and internal
pressure in the compression chamber 30, to open or close the discharge outlet 45
15 and discharge the compressed refrigerant. The discharge pressure in the airtight
container 3 varies with operational conditions of the refrigeration cycle. The
discharge mechanism 40 is thus caused to perform opening-closing operation by
relative height in pressure. The valve body 41, for example, opens when pressure is
higher than or equal to a specified pressure relative to discharge pressure in the
20 airtight container 3. Gas refrigerant discharged from the discharge outlet 45 is
discharged into a space in the airtight container 3 through the discharge outlet 45
located inside the discharge muffler 17. The discharged gas refrigerant passes
through a gap in the motor unit 20 and is discharged outside the airtight container 3
through the discharge pipe 2a, which is interlinked to a top portion of the airtight
25 container 3. The refrigerant discharged outside the airtight container 3 circulates in
the refrigeration cycle and turns back to the accumulator 300 again.
[0047]
[Operation of Discharge Mechanism 40]
Operation of the discharge mechanism 40 is described next. First, when the
30 internal pressure in the compression chamber 30 is lower than the internal pressure

18
in the guide hole 42 in the discharge mechanism 40, the valve body 41 receives a
load in a direction in which the valve body 41 closes the discharge outlet 45 from the
spring force of the spring 43 and the pressure in the guide hole 42. The end face of
the valve body 41 that faces toward the compression chamber 30, without protruding
5 from the corresponding end face of the compression chamber 30, closes the
discharge outlet 45 and receives the internal pressure in the compression chamber
30.
[0048]
Next, refrigerant is compressed in the compression chamber 30 and the end
10 face of the valve body 41 that faces toward the compression chamber 30 receives the
internal pressure. In a case in which the load from the internal pressure to the end
face of the valve body 41 that faces toward the compression chamber 30 is larger
than resultant force of the internal pressure in the guide hole 42 in the discharge
mechanism 40 and the spring force of the spring 43, the valve body 41, which closes
15 the discharge outlet 45, moves toward the spring 43 along the guide hole 42 as
illustrated in Fig. 3. The valve body 41 then opens the discharge outlet 45.
[0049]
When the discharge outlet 45 opens, a discharge course is formed through
which refrigerant is discharged. High-temperature and high-pressure gas refrigerant
20 discharged from the discharge outlet 45 is emitted into the airtight container 3.
Specifically, the refrigerant passes through a portion inside the guide hole 42 and
under the valve body 41, passes through the flange portion of the shaft bearing 14, as
indicated by an arrow a, passes through a hole provided to the side face of the guide
hole 42, as indicated by an arrow b, and flows into the discharge muffler 17. High25 pressure refrigerant inside the discharge muffler 17 subsequently passes through a
gap defined between the shaft bearing 14 and the discharge muffler 17 and a hole
opened in the discharge muffler 17, as indicated by an arrow c, and is discharged into
the airtight container 3 of the compressor 100. When discharge of the refrigerant is
completed, the valve body 41 moves to the discharge outlet 45 by the spring force of
30 the spring 43 and starts closing the discharge outlet 45. The internal pressure in the

19
compression chamber 30 is then lower than the pressure in the airtight container 3.
Next, as illustrated in Fig. 2, the distal end of the valve body 41 that faces toward the
compression chamber 30 is pressed against the valve-body seat portion 46c, which is
located at the distal end of the discharge outlet 45, by a pressure difference between
5 pressure in the guide hole 42 and pressure in the compression chamber 30 and the
discharge outlet 45 is fully closed.
[0050]
When the compressor 100 operates, refrigerating machine oil that remains in
the airtight container 3 is drawn up to the main shaft 11 by the oil-supply pump 70.
10 The refrigerating machine oil drawn up to the main shaft 11 is supplied to the
discharge muffler 17 from the oil-supply hole 11_1 in the main shaft 11, which is
referable to Fig. 4. The refrigerating machine oil supplied to the discharge muffler 17
drips from the oil-supply hole 17_1 in the discharge muffler 17 and is supplied onto
the communication hole 44, which is located under the oil-supply hole 17_1. The
15 refrigerating machine oil supplied to the communication hole 44 passes through the
communication hole 44 and flows through a gap between the valve body 41 and the
side face of the guide hole 42.
[0051]
A threshold value for the internal pressure in the compression chamber 30 at
20 which discharge operation of refrigerant is performed may be an absolute value.
The spring 43 does not have to operate in the guide hole 42. To reduce pressure
loss of refrigerant that passes through the communication hole 44, another spring 43
may also be provided to a portion other than the guide hole 42 such that the guide
hole 42 is increased in capacity.
25 [0052]
[Advantageous Effects]
In the compressor 100 according to Embodiment 1, refrigerating machine oil is
supplied to the communication hole 44. The refrigerating machine oil supplied to the
communication hole 44 passes through the guide hole 42 and flows through the gap
30 between the valve body 41 and the side face of the guide hole 42. The refrigerating

20
machine oil covers the outside surface of the valve body 41 and jamming is thus
prevented from being caused around the valve body 41 in the compressor 100. The
valve body 41 is thus prevented from being worn down, improper closure at the
compression chamber is less likely to be caused and efficiency of the compressor 100
5 is improved and a breakdown in the compressor 100 is prevented.
[0053]
Also, the gap between the side face of the valve body 41 and the side face of
the guide hole 42 is less than 100 [μm] and, when the compressor 100 operates, an
oil surface is formed between the side face of the valve body 41 and the side face of
10 the guide hole 42. Jamming is therefore prevented from being caused around the
valve body 41. Efficiency of the compressor 100 is therefore improved and a
breakdown in the compressor 100 is therefore prevented.
[0054]
In addition, in the compressor 100 according to Embodiment 1, in a case in
15 which pressure in the guide hole 42 in the guide lid 46 is higher than pressure in the
compression chamber 30, the valve body 41 moves in the guide hole 42 and the
discharge outlet 45 is closed. Refrigerant discharged from the discharge outlet 45 is
discharged into the airtight container 3. The communication hole 44 communicates
with the space in the airtight container 3 and discharge refrigerant, which is higher in
20 pressure than refrigerant that remains in the guide hole 42, thus compresses a space
in the guide hole 42 and above the valve body 41. Resultant damper effect thus
prevents the valve body 41 from slowly closing the discharge outlet 45.
[0055]
In addition, in the compressor 100 according to Embodiment 1, the
25 communication hole 44 is located in the guide lid 46. The diameter of the
communication hole 44 is smaller than the inner diameter of the guide lid 46. When
the valve body 41 rises, a small amount of refrigerant in a space between the valve
body 41 and the closure portion 46a does not therefore passes through the
communication hole 44. Such remaining refrigerant is compressed and the valve
30 body 41 is pushed back. At this time, the pressure of the refrigerant, which remains

21
in the space between the valve body 41 and the closure portion 46a, is further higher
than the pressure of high-pressure refrigerant that has been compressed and
discharged into the airtight container 3. This damper effect causes the valve body
41 to start descending immediately after the valve body 41 finishes rising. The valve
5 body 41 thus achieves closure and is seated on the valve-body seat portion 46c
located in the shaft bearing 14 not later than a desired seating timing.
[0056]
In addition, in the compressor 100 according to Embodiment 1, the horizontal
outer diameter of the communication hole 44 is specified to be smaller than the
10 horizontal outer diameter of the valve body 41 and the valve body 41 is thus further
prevented from causing closure at reduced speed.
[0057]
In addition, in the compressor 100 according to Embodiment 1, the one end of
the guide hole 42 that faces toward the compression chamber 30 is formed such that
15 the one end coincides with the corresponding end face of the compression chamber
30 and fits on the inside wall of the cylinder 13. Refrigerant thus flows an increased
area of a flow passage with reduced discharge pressure loss.
[0058]
In addition, in the compressor 100 according to Embodiment 1, the discharge
20 course is configured such that the compression chamber 30, the valve body 41, and
the discharge outlet 45 are sequentially arranged. Also, immediately after the
compression chamber 30, the valve body 41 closes the discharge outlet 45. Dead
volume in the compressor 100 is thus reduced. Reduction in efficiency of the
compressor 100 caused by re-expansion of refrigerant is thus prevented.
25 [0059]
In addition, in the compressor 100 according to Embodiment 1, the end face of
the compression chamber 30 and the end face of the valve body 41 that faces toward
the compression chamber 30 coincide with each other at the same plane. The dead
volume in the compressor 100 is thus possibly minimized and the valve body 41
30 protrudes inside the compression chamber 30 and the valve body 41 is thus

22
prevented from colliding with the rolling piston 16.
[0060]
In addition, in the compressor 100 according to Embodiment 1, the cylindrical
portion 46b of the guide lid 46 is formed as a part separate from the shaft bearing 14,
5 the structure of the shaft bearing 14 is thus simplified and the compressor 100 is
provided at low cost.
[0061]
In addition, in the compressor 100 according to Embodiment 1, in a case in
which the cylindrical portion 46b of the guide lid 46 and the shaft bearing 14 are
10 integrally formed with each other, the core of the valve body 41 and the core of the
valve-body seat portion 46c are prevented from being off-centered and the
compressor 100 with high reliability is thus provided.
[0062]
The shaft bearing 14 has sliding portions against which the main shaft 11 and
15 the rolling piston 16 slide and is thus distorted by units of several to tens [μm]. Such
distortion negatively affects reliability of the compressor 100. Specifically, at a
portion distorted, metal parts are in local contact with each other and seizure is thus
caused. In the compressor 100 according to Embodiment 1, the guide lid 46 may
also be screwed and fixed to the shaft bearing 14. In this case, when the
20 compressor 100 is assembled, reduced force is applied to the shaft bearing 14 and
the shaft bearing 14 is thus less distorted.
[0063]
In addition, in the compressor 100 according to Embodiment 1, the horizontal
outer diameter of the communication hole 44 is smaller than the horizontal outer
25 diameter of the valve body 41. The communication hole 44 thus serves as a
squeeze outlet and an advantageous effect is produced in which damper effect in the
communication hole 44 to be reduced is made not to be reduced more than or equal
to a designed and desired extent. Also, when the discharge outlet 45 is to be closed,
another advantageous effect is produced in helping immediate closure by the valve
30 body 41.

23
[0064]
Embodiment 2
Embodiment 2 differs from Embodiment 1 in a method of oil supply to the
communication hole 44 in the discharge mechanism 40. Fig. 4 is a diagram that
5 illustrates a method of oil supply to the communication hole 44 in the discharge
mechanism 40 in the compressor 100 according to Embodiment 2. Portions
illustrated in Fig. 4 that are same as the portions illustrated in Fig. 1 to Fig. 3 are
described by use of the same reference signs.
[0065]
10 As illustrated in Fig. 4, the oil-supply hole 11_1, through refrigerating machine
oil is discharged, is located in the main shaft 11. The discharge muffler 17 also
serves as the guide lid 46 and in which the communication hole 44 is opened. The
communication hole 44 is located at a position lower than the oil-supply hole 11_1 in
the main shaft 11. The discharge muffler 17 has an oil-reservoir portion 17_2
15 provided at an upper portion of the communication hole 44. The oil-reservoir portion
17_2 is formed by the discharge muffler 17 and is box-shaped such that refrigerating
machine oil is to be stored, however, may also be formed in another shape. In a
lower portion of the oil-reservoir portion 17_2, the communication hole 44 is opened.
[0066]
20 Refrigerating machine oil that flows out from the oil-supply hole 11_1 in the
main shaft 11 slides down the surface of the discharge muffler 17 and is thus stored in
the oil-reservoir portion 17_2. The refrigerating machine oil stored in the oil-reservoir
portion 17_2 passes through the communication hole 44 and flows through the gap
between the valve body 41 and the side face of the guide hole 42.
25 [0067]
In the compressor 100 according to Embodiment 2, the communication hole 44
is located at a position lower than the oil-supply hole 11_1 in the main shaft 11,
refrigerating machine oil that flows out from the oil-supply hole 11_1 in the main shaft
11 thus slides down the surface of the discharge muffler 17 and is stored in the oil30 reservoir portion 17_2. Refrigerating machine oil is thus always supplied to the

24
discharge mechanism 40.
[0068]
Also, in the compressor 100 according to Embodiment 2, the discharge muffler
17 has the communication hole 44 and the discharge muffler 17 thus also serves as
5 the guide lid 46. The number of parts in the compressor 100 is thus reduced and the
compressor 100 is provided at low cost.
[0069]
Embodiment 3
Embodiment 3 differs from Embodiment 1 and Embodiment 2 in a method of oil
10 supply to the communication hole 44 in the discharge mechanism 40. Fig. 5 is a
diagram that illustrates a method of oil supply to the communication hole 44 in the
discharge mechanism 40 in the compressor 100 according to Embodiment 3.
Portions illustrated in Fig. 5 that are same as the portions illustrated in Fig. 1 to Fig. 4
are described by use of the same reference signs.
15 [0070]
Fig. 5 differs from Fig. 3 in that an oil-supply pipe 18 is provided, through which
the oil-supply hole 17_1 in the discharge muffler 17 and the communication hole 44
communicate with each other. Also, at the upper surface of the discharge muffler 17
according to Embodiment 3, the oil-reservoir portion 17_2 is located. A space
20 defined by walls provided around the oil-supply hole 17_1 is the oil-reservoir portion
17_2 according to Embodiment 3.
[0071]
When the compressor 100 operates, refrigerating machine oil that remains in
the airtight container 3 is drawn up to the main shaft 11 by the oil-supply pump 70.
25 The refrigerating machine oil drawn up to the main shaft 11 is supplied to the
discharge muffler 17 from the oil-supply hole 11_1 in the main shaft 11, which is
referable to Fig. 4. The refrigerating machine oil supplied to the discharge muffler 17
remains in the oil-reservoir portion 17_2 of the discharge muffler 17. The
refrigerating machine oil that remains in the oil-reservoir portion 17_2 passes
30 sequentially through the oil-supply hole 17_1 and the oil-supply pipe 18 and is

25
supplied to the communication hole 44, which is located under the oil-reservoir
portion 17_2. The refrigerating machine oil supplied to the communication hole 44
passes through the communication hole 44 and flows through the gap between the
valve body 41 and the side face of the guide hole 42.
5 [0072]
In the compressor 100 according to Embodiment 3, when the compressor 100
operates, refrigerating machine oil that remains in the airtight container 3 is drawn up
to the main shaft 11 by the oil-supply pump 70. The refrigerating machine oil drawn
up to the main shaft 11 is supplied to the discharge muffler 17 from the oil-supply hole
10 11_1 in the main shaft 11. The refrigerating machine oil supplied to the discharge
muffler 17 passes through from the oil-supply hole 17_1 and remains in the oilreservoir portion 17_2 of the discharge muffler 17. The refrigerating machine oil that
remains in the oil-reservoir portion 17_2 passes from the oil-supply hole 17_1 in the
discharge muffler 17 through the oil-supply pipe 18 and is supplied to the
15 communication hole 44.
[0073]
In the compressor 100 according to Embodiment 3, the refrigerating machine
oil is therefore supplied from the oil-reservoir portion 17_2 in the discharge muffler 17
to the communication hole 44 through the oil-supply pipe 18 and refrigerating
20 machine oil is thus supplied to the discharge mechanism 40 without impedance from
turbulent flow of fluid in the discharge muffler 17.
[0074]
Embodiment 4
Fig. 6 is a diagram that illustrates an oil-supply groove 81 that is linear-shaped
25 and is provided to the discharge mechanism 40 in the compressor 100 according to
Embodiment 4. Specifically, as illustrated in Fig. 6, the oil-supply groove 81 is linearshaped in a vertical direction and along the inner face of the closure portion 46a and
the inner face of the cylindrical portion 46b of the guide lid 46. The oil-supply groove
81 does not extend up to the valve-body seat portion 46c. The oil-supply groove 81
30 has its width of 2 [mm] and its height of 4 [mm].

26
[0075]
The oil-supply groove 81 is not limited to the oil-supply groove 81 that is linearshaped. Fig. 7 is a diagram that illustrates an oil-supply groove 81_1 that is spiralshaped and is provided to the discharge mechanism 40 in the compressor 100
5 according to Embodiment 4.
[0076]
To the oil-supply groove 81 or the oil-supply groove 81_1, refrigerating machine
oil that is supplied to the communication hole 44 is supplied.
[0077]
10 In the compressor 100 according to Embodiment 4, refrigerating machine oil is
supplied to the oil-supply groove 81 or the oil-supply groove 81_1 and jamming is
therefore further prevented from being caused around the valve body 41.
[0078]
Embodiment 5
15 Fig. 8 is a refrigerant circuit diagram that schematically illustrates a
configuration of a refrigerant circuit in a refrigeration cycle apparatus 200 according to
Embodiment 5. With reference to Fig. 8, the configuration and operation of the
refrigeration cycle apparatus 200 is described below. The refrigeration cycle
apparatus 200 according to Embodiment 5 is a refrigerant circuit to which any of the
20 compressors 100 according to Embodiment 1 to Embodiment 3 is provided as one
component. Fig. 8 illustrates, for descriptive purposes, a case in which the
compressor 100 according to Embodiment 1 is provided.

The refrigeration cycle apparatus 200 has the compressor 100, a flow-passage
25 selector 151, a first heat exchanger 152, an expansion device 153, and a second heat
exchanger 154. The compressor 100, the first heat exchanger 152, the expansion
device 153, and the second heat exchanger 154 are connected to each other by a
high-pressure pipe 155a and the low-pressure pipe 155b and thus form the refrigerant
circuit. Also, to an upper stream of the compressor 100, the accumulator 300 is
30 provided.

27
[0079]
The compressor 100 is configured to compress sucked refrigerant into a hightemperature and high-pressure state. Refrigerant compressed in the compressor
100 is discharged from the compressor 100 and sent to the first heat exchanger 152
5 or the second heat exchanger 154.
[0080]
The flow-passage selector 151 is configured to switch respective refrigerant
flows for cooling operation and heating operation. In other words, the flow-passage
selector 151 is switched such that the compressor 100 and the second heat
10 exchanger 154 are connected to each other for heating operation and such that the
compressor 100 and the first heat exchanger 152 are connected to each other for
cooling operation. The flow-passage selector 151 is preferably, for example, a fourway valve. Combination of two-way valves and three-way valves, however, may
also be used as the flow-passage selector 151.
15 [0081]
The first heat exchanger 152 is configured to operate as an evaporator during
heating operation and operate as a condenser during cooling operation. In other
words, in a case in which the first heat exchanger 152 operates as an evaporator, the
first heat exchanger 152 allows low-temperature and low-pressure refrigerant that
20 flows out from the expansion device 153 and air supplied by, for example, an
unillustrated air-sending device to exchange heat with each other and lowtemperature and low-pressure liquid refrigerant or two-phase gas-liquid refrigerant
thus evaporates. On the other hand, in a case in which the first heat exchanger 152
operates as a condenser, the first heat exchanger 152 allows high-temperature and
25 high-pressure refrigerant discharged from the compressor 100 and air supplied by, for
example, an unillustrated air-sending device to exchange heat with each other and
high-temperature and high-pressure gas refrigerant thus condenses. The first heat
exchanger 152 may also be a refrigerant-water heat exchanger. In this case, the
first heat exchanger 152 allows refrigerant and a heat medium, such as water, to
30 exchange heat with each other.

28
[0082]
The expansion device 153 is configured to expand and decompress refrigerant
that flows out from the first heat exchanger 152 or the second heat exchanger 154.
The expansion device 153 is preferably, for example, a component such as an electric
5 expansion valve that is configured to adjust a flow rate of refrigerant. To the
expansion device 153, not only the electric expansion valve but also a mechanical
expansion valve in which a diaphragm is use as a pressure receiver, a capillary tube,
or other component is applicable.
[0083]
10 The second heat exchanger 154 is configured to operate as a condenser
during heating operation and operate as an evaporator during cooling operation. In
other words, in a case in which the second heat exchanger 154 operates as a
condenser, the second heat exchanger 154 allows high-temperature and highpressure refrigerant discharged from the compressor 100 and air supplied by, for
15 example, an unillustrated air-sending device to exchange heat with each other and
high-temperature and high-pressure gas refrigerant thus condenses. On the other
hand, in a case in which the second heat exchanger 154 operates as an evaporator,
the second heat exchanger 154 allows low-temperature and low-pressure refrigerant
that flows out from the expansion device 153 and air supplied by, for example, an
20 unillustrated air-sending device to exchange heat with each other and lowtemperature and low-pressure liquid refrigerant or two-phase gas-liquid refrigerant
thus evaporates. The second heat exchanger 154 may also be a refrigerant-water
heat exchanger. In this case, the second heat exchanger 154 allows refrigerant and
a heat medium, such as water, to exchange heat with each other.
25 [0084]
Also, to the refrigeration cycle apparatus 200, a controller 160 is provided,
which is configured to exercise integrated control of the entirety of the refrigeration
cycle apparatus 200. Specifically, the controller 160 controls a driving frequency of
the compressor 100 in accordance with required cooling capacity or required heating
30 capacity. The controller 160 also controls an opening degree of the expansion

29
device 153 depending on an operational state and a selected mode. In addition, the
controller 160 controls the flow-passage selector 151 in accordance with a selected
mode.
[0085]
5 The controller 160 controls an actuator, such as the compressor 100, the
expansion device 153, and the flow-passage selector 151, in accordance with an
operational instruction from a user and by use of pieces of information sent from
unillustrated temperature sensors and unillustrated pressure sensors.
[0086]
10 The controller 160 may be formed by a piece of hardware, such as a circuit
device, that is configured to perform functions of the controller 160 and may also be
formed by an arithmetic unit, such as a microcomputer and a CPU, and software run
on the arithmetic unit.
[0087]
15 The controller 160 is formed by a dedicated piece of hardware or is formed by
a central processing unit, which is also referred to as a CPU, a central processor, a
processing unit, an arithmetic unit, a microprocessor, a microcomputer, and a
processor, and that is configured to execute a program stored in a memory. In a
case in which the controller 160 is a dedicated piece of hardware, the controller 160
20 corresponds to, for example, a single circuit, a composite circuit, an application
specific integrated circuit (ASIC), a field programmable gate array (FPGA), or
combination of these components above listed. Functions performed by the
controller 160 may be performed by respective pieces of hardware. The functions
may also be performed by a single piece of hardware. In a case in which the
25 controller 160 is formed by a CPU, functions performed by the controller 160 are
performed by software, firmware, or combination of software and firmware. Software
and firmware are described as a program and stored in a memory. The CPU reads
out and executes the program stored in the memory and performs the functions of the
controller 160. The memory here is, for example, a non-volatile or volatile
30 semiconductor memory such as RAM, a ROM, a flash memory, an EPROM, and an

30
EEPROM. One of functions of the controller 160 may be performed by a dedicated
piece of hardware and another may be performed by software or firmware.
[0088]

5 Operation of the refrigeration cycle apparatus 200 is described below together with
refrigerant flow. With reference to, as an example, a case in which heat-exchange
fluid at the first heat exchanger 152 and the second heat exchanger 154 is air,
operation of the refrigeration cycle apparatus 200 during cooling operation is
described below. In Fig. 8, dotted-line arrows indicate refrigerant flow during cooling
10 operation, and solid-line arrows indicate refrigerant flow during heating operation.
[0089]
The compressor 100 is driven and refrigerant in a high-temperature and highpressure gas state is thus discharged from the compressor 100. The hightemperature and high-pressure gas refrigerant, which is single-phase, discharged
15 from the compressor 100 flows into the first heat exchanger 152. In the first heat
exchanger 152, the high-temperature and high-pressure gas refrigerant that flows in
and air supplied by an unillustrated air-sending device exchange heat with each other
and the high-temperature and high-pressure gas refrigerant thus condenses into highpressure liquid refrigerant, which is single-phase.
20 [0090]
The high-pressure liquid refrigerant sent from the first heat exchanger 152
turns into, by the expansion device 153, refrigerant in a two-phase state of lowpressure gas refrigerant and liquid refrigerant. The refrigerant in the two-phase state
flows into the second heat exchanger 154. In the second heat exchanger 154, the
25 refrigerant in the two-phase state that flows in and air supplied by an unillustrated airsending device exchange heat with each other and the liquid refrigerant included in
the refrigerant in the two-phase state thus evaporates and the refrigerant in the twophase state turns into low-pressure gas refrigerant, which is single-phase. The lowpressure gas refrigerant sent from the second heat exchanger 154 flows into the
30 compressor 100 through the accumulator 300 and is compressed into high-

31
temperature and high-pressure gas refrigerant and is discharged from the
compressor 100 again. Subsequently, this cycle is repeated.
[0091]
With the refrigeration cycle apparatus 200 according to Embodiment 5, the
5 refrigeration cycle apparatus 200 in which the compressor 100 with high compression
efficiency is used is therefore provided.
[0092]
Operation of the refrigeration cycle apparatus 200 during heating operation is
performed by causing the flow-passage selector 151 to switch the refrigerant flow to
10 flows indicated by the solid-line arrows illustrated in Fig. 8.
[0093]
Without the flow-passage selector 151 provided to a discharge portion of the
compressor 100 being provided, the refrigerant flow may also be in a constant
direction.
15 [0094]
Also, a refrigerant used in the refrigeration cycle apparatus 200 is not
particularly limited and a refrigerant such as carbon dioxide, R410A, R32, and
HFO1234yf may also be used.
[0095]
20 In addition, application examples of the refrigeration cycle apparatus 200
include an air-conditioning apparatus, a water heater, a freezer, and an airconditioning and water-heating composite device.
[0096]
Embodiment 6
25 In Embodiment 6, types of refrigerants used in the refrigeration cycle apparatus
200 according to Embodiment 4 are described.
[0097]
A refrigerant used in the refrigeration cycle apparatus 200 according to
Embodiment 6 is lower than an R410A refrigerant in gas density. Such refrigerants
30 include, for example, R134a, R1234yf, R513A, R463A, R290, R454C, R454A, R404A,

32
R448A, R449A, R454B, R452B, and R466A.
[0098]
Fig. 9 is a chart that illustrates gas density in refrigerant sucked in the
compressor and gas density in refrigerant discharged from the compressor under
5 rated conditions of compressor operation in a typical refrigeration cycle stipulated in
ASHRAE.
[0099]
The ASHRAE here is an acronym of American Society of Heating, Refrigerating
and Air-Conditioning Engineers. The rated conditions of compressor operation is
10 also widely referred to as ASRAE-T conditions. In the conditions, condensing
temperature is defined to 54.4 degrees C, an evaporating temperature is defined to
7.2 degrees C, a degree of subcooling is defined to 8.3 degrees C, and a degree of
superheat is defined to 27.8 degrees C.
[0100]
15 Fig. 9 lists refrigerants of R134a, R1234yf, R513A, R463A, R290, R454C,
R454A, R404A, R448A, R449A, R454B, R452B, and R466A. These refrigerants
each are, as illustrated in Fig. 9, lower than R410A in gas density both in a case in
which refrigerant is sucked into the compressor and in a case in which refrigerant is
discharged from the compressor.
20 [0101]
Fluid such as refrigerant gas typically increases in pressure loss in proportion
to flow velocity of the fluid. As long as refrigerant is to be circulated with the same
weight, flow velocity of gas has to be increased when density reduces. In other
words, refrigerant gas with low density increases to be higher in pressure loss than
25 refrigerant gas with high density. Such pressure loss is caused at various portions in
the refrigeration cycle. In particular, its effect is remarkable at a discharge valve of
compression and other portion at which a flow passage is narrow and flow velocity of
fluid is high.
[0102]
30 Pressure loss in a flow passage causes energy loss and thus reduces

33
efficiency in the entirety of the refrigeration cycle. As a discharge valve in a rotary
compressor, a reed valve is typically used. Fig. 10 is a diagram that illustrates an
example of a reed valve in a compressor. As illustrated in Fig. 10, one end of a reed
valve 401 and one end of a restrictor plate 402 are fixed to the vicinity of a discharge
5 hole 405 provided in an end face of the shaft bearing 14 by a fastener rivet 403. The
restrictor plate 402 restricts movement of the reed valve. The reed valve 401 is
seated on a seat portion 404 and closes the discharge hole 405. The reed valve 401
is lifted up by pressure increase in the compression chamber 30. The reed valve
401 is, as described above, structured such that the reed valve 401 is lifted up from
10 its one end, a lift distance R between the end face of the shaft bearing 14 and a
portion close to a portion at which the reed valve 401 is fixed is shorten, and the
entire area of a flow passage is reduced.
[0103]
Fig. 11 is a diagram that illustrates the lift distance R of the valve body 41 in the
15 compressor 100 used in the refrigeration cycle apparatus 200 according to
Embodiment 6. As illustrated in Fig. 11, the valve body 41 in the discharge
mechanism 40 in the compressor 100 moves in the guide hole 42 by the spring 43 in
the vertical direction. The lift distance R is therefore uniform for the entirety of the
valve body 41 and the entire area of a refrigerant flow passage is increased and
20 larger than a case of the reed valve 401.
[0104]
The area of the refrigerant flow passage is increased and flow velocity at the
discharge outlet 45 is thus reduced and pressure loss at the discharge outlet 45 is
reduced. Such an effect is remarkable with refrigerant that has low gas density.
25 [0105]
The refrigeration cycle apparatus 200 according to Embodiment 6 applies a
refrigerant that is lower in gas density than R410A, which is widely used in the world
at present, to the refrigeration cycle apparatus 200 according to Embodiment 4. The
refrigeration cycle apparatus 200 according to Embodiment 6 is therefore configured
30 to reduce pressure loss and obtains a refrigeration cycle with high efficiency. In

34
particular, in a case in which R290, which is remarkably higher than each of the other
refrigerants in suction gas density and discharge gas density, is used as refrigerant,
the refrigeration cycle apparatus 200 is configured to reduce pressure loss and
obtains a refrigeration cycle with high efficiency.
5 [0106]
The embodiments are presented above as examples and not intended to limit
the scope of claims. The embodiments may also be achieved by other various forms
and may also be partially omitted, replaced, or changed in various forms without
departing from the gist of the embodiments. These embodiments and their
10 modifications are included in the scope of the embodiments and the gist of
embodiments.
Reference Signs List
[0107]
1: lower container, 2: upper container, 2a: discharge pipe, 3: airtight container,
15 10: compression mechanism unit, 11: main shaft, 11a: main shaft portion, 11_1: oilsupply hole in main shaft 11, 12: eccentric shaft portion, 13: cylinder, 14, 14a: shaft
bearing, 15: partition plate, 16: rolling piston, 17: discharge muffler, 17_1: oil-supply
hole in discharge muffler 17, 17_2: oil-reservoir portion, 18: oil-supply pipe, 20: motor
unit, 21: rotor, 22: stator, 30: compression chamber, 31a: first suction pipe, 31b:
20 second suction pipe, 40: discharge mechanism, 41: valve body, 42: guide hole, 43:
spring, 44: communication hole, 45: discharge outlet, 46: guide lid, 46a: closure
portion, 46b: cylindrical portion, 46c: valve-body seat portion, 50: suction inlet, 60:
suction muffler, 70: oil-supply pump, 81, 81_1: oil-supply groove, 100: compressor,
151: flow-passage selector, 152: first heat exchanger, 153: expansion device, 154:
25 second heat exchanger, 155a: high-pressure pipe, 155b: low-pressure pipe, 160:
controller, 200: refrigeration cycle apparatus, 300: accumulator, 401: reed valve, 402:
restrictor plate, 403: fastener rivet, 404: seat portion, 405: discharge hole, R: lift
distance

35
We Claim:
[Claim 1]
5 A compressor comprising:
an airtight container;
a cylinder provided in the airtight container and in which a compression
chamber is provided in which refrigerant is compressed;
a main shaft provided in the airtight container;
10 a shaft bearing provided to the main shaft and to which a discharge outlet is
provided through which refrigerant compressed in the compression chamber is
discharged; and
a discharge mechanism that has a guide lid that is provided to the shaft bearing
and has a guide hole in the guide lid and a valve body provided in the guide hole and
15 is configured to open and close the discharge outlet when the valve body moves in
the guide hole,
the guide lid having a communication hole through which the guide hole and an
inside of the airtight container into which refrigerant discharged from the discharge
outlet is discharged communicate with each other,
20 to the communication hole, refrigerating machine oil that remains in the airtight
container being supplied.
[Claim 2]
The compressor of claim 1, further comprising:
an oil-supply pump that is provided to a lowermost end of the main shaft and
25 configured to draw the refrigerating machine oil that remains in the airtight container
into the main shaft; and
a discharge muffler to which the refrigerating machine oil drawn by the oilsupply pump into the main shaft is supplied, wherein,
in the discharge muffler, an oil-supply hole is opened, through which the
30 refrigerating machine oil is supplied to the communication hole.

36
[Claim 3]
The compressor of claim 2, wherein the discharge muffler has an oil-reservoir
portion provided at an upper portion of the oil-supply hole.
[Claim 4]
5 The compressor of any one of claims 1 to 3, wherein,
in the main shaft, an oil-supply hole is opened, through which the refrigerating
machine oil is discharged, and
the communication hole is located at a position lower than the oil-supply hole.
[Claim 5]
10 The compressor of claim 2 or 3, further comprising an oil-supply pipe through
which the oil-supply hole in the discharge muffler and the communication hole
communicate with each other.
[Claim 6]
The compressor of any one of claims 1 to 5, wherein, in a side face in a
15 horizontal direction of the guide lid that is adjacent to the guide hole, a groove is
formed, to which the refrigerating machine oil is supplied from the communication
hole.
[Claim 7]
The compressor of any one of claims 1 to 6, wherein a horizontal gap between
20 a side face of the valve body and a side face of the guide hole is less than 100 [μm].
[Claim 8]
A refrigeration cycle apparatus, wherein refrigerant circulates sequentially
through the compressor of any one of claims 1 to 7, a first heat exchanger, an
expansion device, and a second heat exchanger.
25 [Claim 9]
The refrigeration cycle apparatus of claim 8, wherein the refrigerant is a
refrigerant that is lower than R410A in gas density.
30

[Claim 10]
The refrigeration cycle apparatus of claim 9, wherein the refrigerant is R290.