EP3312424A1

EP3312424A1 - Sealed rotary compressor

Info

Publication number: EP3312424A1
Application number: EP17196702.9A
Authority: EP
Inventors: Ikuo Esaki; Shigeki Miura; Hajime Sato; Makoto Ogawa; Masanari Uno; Hirofumi SHIMAYA
Original assignee: Mitsubishi Heavy Industries Thermal Systems Ltd
Current assignee: Mitsubishi Heavy Industries Thermal Systems Ltd
Priority date: 2016-10-19
Filing date: 2017-10-16
Publication date: 2018-04-25
Also published as: JP6270080B1; JP2018066314A

Abstract

Sealed rotary compressor capable of achieving high efficiency by defining geometrical relation of electric motor, compression chamber diameter and rotary shaft. An electric motor 3 in a sealed rotary compressor 1 includes a rotor core 12 which fixes a rotary shaft 5 to the inner portion of the rotor core 12, a stator core 11 which is fixed to a case 2 on an outer peripheral side of the rotor core 12, and a stator coil 13 which is provided in the stator core 11, and when an outer diameter of the stator core 11 is defined as Φ Mο and an inner diameter of a cylinder 16 forming a compression chamber 19 is defined as Φ Dc, Expression: ΦDc / Φ Mo s 0.350 is satisfied.

Description

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates to a sealed rotary compressor which compresses a fluid.

Description of Related Art

In the related art, for example, a sealed rotary compressor is known as a compressor which is used for refrigeration air conditioning. For example, the compressor is described in Patent Document 1.
As described in Patent Document 1, in a sealed rotary compressor, a rotary shaft, a motor which rotates the rotary shaft, a piston rotor which is eccentrically attached to the rotary shaft, a cylinder having a piston disposed inside the cylinder, or the like is mainly provided inside a sealed container. In the compressor, a refrigerant gas is sucked into the cylinder via a suction pipe connected to a side wall of the cylinder and the refrigerant gas is compressed by rotation of the piston rotor.
[Patent Document 1] Japanese Unexamined Patent Application, First Publication No. 2011-153526

SUMMARY OF THE INVENTION

In recent years, further improvement in efficiency of the compressor is required. However, an installation space or the like is limited, and thus, there is a problem that it is difficult to considerably change a structure or a shape of the compressor for the purpose of high efficiency.
Accordingly, the present invention provides a sealed rotary compressor capable of achieving high efficiency by a simple method.
According to an aspect of the present invention, there is provided a sealed rotary compressor, including: an electric motor; a rotary shaft which is capable of being rotated around an axis by the electric motor; a piston rotor which is provided on the rotary shaft and rotates to be eccentric with respect to the axis according to rotation of the rotary shaft; a cylinder in which a compression chamber in which the piston rotor is accommodated is formed inside the cylinder and a supply flow path through which a refrigerant is supplied to the compression chamber is formed; a case which surrounds the cylinder to form, between the cylinder and the case, a discharge space to which the refrigerant compressed by the piston rotor is exhausted and in which the electric motor, the rotary shaft, the piston rotor, and the cylinder are accommodated in a sealed manner; and a bearing which supports the rotary shaft to the case, in which the electric motor includes a rotor core which fixes the rotary shaft to the inner portion of the rotor core, a stator core which is fixed to the case on an outer peripheral side of the rotor core, and a stator coil which is provided in the stator core, and when an outer diameter of the stator core is defined as ΦMo and an inner diameter of the cylinder is defined as ΦDc, the following Expression (1) is satisfied. $ΦDc / ΦMo \leq 0.350$
An iron loss (eddy current loss) at the stator core can be reduced as the outer diameter ΦMo of the stator core increases, and efficiency of the electric motor is improved.
Under conditions of obtaining predetermined compression capacity by the compressor, it is necessary to increase the number of revolution of the electric motor if a cylinder exclusion volume (a volume of the compression chamber) decreases. The cylinder exclusion volume is correlated with the inner diameter ΦDc of the cylinder, and the inner diameter ΦDc of the cylinder decreases as the cylinder exclusion volume (the volume of the compression chamber) decreases. Accordingly, under conditions of obtaining the predetermined compression capacity, it is necessary to increase the number of revolution of the electric motor as the inner diameter ΦDc of the cylinder decreases.
Here, if the electric motor is operated at a region of a low number of revolution, the efficiency decreases. As described above, since the number of revolution of the electric motor increases if the inner diameter ΦDc of the cylinder decreases, as a result, the efficiency of the electric motor is improved.
Accordingly, by setting the outer diameter ΦMo of the stator core large and (or) setting the inner diameter ΦDc of the cylinder small and forming the electric motor and the cylinder such that the value of ΦDc / ΦMo is 0.350 or less, it is possible to achieve improvement of the efficiency of the sealed rotary compressor without significantly changing the installation space or the external shape of the sealed rotary compressor.
In the above-described sealed rotary compressor, when the outer diameter of the stator core is defined as ΦMo and the inner diameter of the cylinder is defined as ΦDc, the following Expression (2) may be further satisfied. $ΦDc / ΦMo \leq 0.320$
According to the sealed rotary compressor, by further setting the outer diameter ΦMo of the stator core large and (or) setting the inner diameter ΦDc of the cylinder small and forming the electric motor and the cylinder such that the value of ΦDc / ΦMo is 0.320 or less, it is possible to achieve further improvement of the efficiency of the sealed rotary compressor without significantly changing the installation space, the external shape, or the like of the sealed rotary compressor.
In the above-described sealed rotary compressor, when the outer diameter of the stator core is defined as ΦMo and the inner diameter of the cylinder is defined as ΦDc, the following Expression (3) may be further satisfied. $0.200 \leq ΦDc / ΦMo \leq 0.320$
According to the sealed rotary compressor, by further setting the outer diameter ΦMo of the stator core large and (or) setting the inner diameter ΦDc of the cylinder small and forming the electric motor and the cylinder such that the value of ΦDc / ΦMo is 0.320 or less and 0.200 or more, it is possible to achieve further improvement of the efficiency of the sealed rotary compressor without significantly changing the installation space, the external shape, or the like of the sealed rotary compressor.
In the above-described sealed rotary compressor, when the outer diameter of the rotary shaft is defined as ΦLJ, the following Expression (4) may be further satisfied. $ΦLJ / ΦMo \leq 0.140$
If the outer diameter ΦLJ of the rotary shaft decreases, it is possible to reduce a sliding loss between the rotary shaft and the bearing or the like, and thus, it is possible to improve machine efficiency of the sealed rotary compressor. As described above, if by the outer diameter ΦMo of the stator core increases, it is possible to reduce the iron loss (eddy current loss) at the stator core and improve the efficiency of the electric motor. Accordingly, by setting the outer diameter ΦLJ of the rotary shaft to be smaller than the outer diameter ΦMo of the stator core and setting the value of ΦLJ / ΦMo to 0.140 or less, it is possible to achieve further improvement of the efficiency of the sealed rotary compressor.
In the above-described sealed rotary compressor, when the outer diameter of the rotary shaft is defined as ΦLJ, the following Expression (5) may be further satisfied. $0.0800 \leq ΦLJ / ΦMo \leq 0.140$
If the outer diameter ΦLJ of the rotary shaft decreases, the sliding loss between the rotary shaft and the bearing or the like can be reduced. However, if the outer diameter ΦLJ of the rotary shaft becomes too small, the rotary shaft easily comes into one-sided contact with the bearing, and the sliding loss increases. Accordingly, by setting the value of ΦLJ / ΦMo to be 0.0800 or more, it is possible to improve machine efficiency of the sealed rotary compressor while preventing the one-sided contact of the rotary shaft, and it is possible to achieve further improvement of the efficiency of the sealed rotary compressor.
In the above-described sealed rotary compressor, when the outer diameter of the rotary shaft is defined as ΦLJ, the following Expression (6) may be further satisfied. $0.106 \leq ΦLJ / ΦMo \leq 0.140$
If the outer diameter ΦLJ of the rotary shaft decreases, the sliding loss between the rotary shaft and the bearing or the like can be reduced. However, if the outer diameter ΦLJ of the rotary shaft becomes too small, the rotary shaft easily comes into one-sided contact with the bearing, and the sliding loss increases. Accordingly, by setting the value of ΦLJ / ΦMo to be 0.106 or more, it is possible to perform the operation in a region in which the sliding loss is minimum while preventing the one-sided contact of the rotary shaft, it is possible to improve the machine efficiency of the sealed rotary compressor, and it is possible to achieve further improvement of the efficiency of the sealed rotary compressor.
According to the above-described sealed rotary compressor, it is possible to achieve high efficiency by a simple method by forming the electric motor and the cylinder based on the above-described simple indexes.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a longitudinal sectional view showing a sealed rotary compressor of an embodiment of the present invention.
FIG. 2 is a graph showing a relationship between an outer diameter ΦMo of a stator core and a motor efficiency of an electric motor.
FIG. 3 is a graph showing a relationship between an inner diameter ΦDc of a cylinder and a number of revolution of the electric motor in a state where predetermined compression capacity of the sealed rotary compressor is exerted.
FIG. 4 is a graph showing a relationship between the number of revolution of the electric motor and the motor efficiency of the electric motor.
FIG. 5 is a graph showing a relationship between the inner diameter ΦDc of the cylinder and the motor efficiency of the electric motor.
FIG. 6 is a graph showing a relationship between an outer diameter ΦLJ of a rotary shaft and machine efficiency.
FIG. 7 is a graph showing a relationship between ΦLJ / ΦMo which is a ratio between the outer diameter ΦLJ of the rotary shaft and the outer diameter ΦMo of the stator core, and a sliding loss at a bearing.

DETAILED DESCRIPTION OF THE INVENTION

Hereinafter, a sealed rotary compressor 1 (hereinafter, referred to as compressor 1) according to an embodiment of the present invention will be described.
As shown in FIG. 1, a compressor 1 includes a cylindrical case 2, an electric motor 3 which is accommodated inside the case 2, a rotary shaft 5 which is driven by the electric motor 3 inside the case 2, bearings 17 and 18 (upper bearing 17 and lower bearing 18) which supports the rotary shaft 5 inside the case 2, a piston rotor 15 which is attached to the rotary shaft 5 inside the case 2, and a cylinder 16 which is provides inside the case 2 and accommodates the piston rotor 15.
The compressor 1 is connected to a refrigerant circuit (not shown). That is, the compressor 1 is a device which is incorporated into the refrigerant circuit including a condenser, an expansion valve, an evaporator, or the like and compresses a refrigerant flowing through a pipe of the refrigerant circuit.
The case 2 includes a tubular body 7, an upper cover 8 which is welded to an upper end of the body 7, and a bottom cover 9 which is welded to a lower end of the body 7. The electric motor 3, the piston rotor 15, and the cylinder 16 are sealed inside the case 2. A suction pipe 10 connected to the cylinder 16 is provided in the body 7. For example, the suction pipe 10 is a pipe through which a refrigerant gas G is sucked into the cylinder 16 via an accumulator (not shown). A discharge space to which the compressed refrigerant gas G is exhausted from the cylinder 16 is formed inside the case 2. The refrigerant gas G filling the inside of the discharge space is discharged to the refrigerant circuit through the discharge pipe 14 penetrating the upper cover 8.
The electric motor 3 includes a rotor core 12, and a stator core 11 and a stator coil 13 disposed on an outer peripheral side of the rotor core 12.
The stator core 11 is formed of an electromagnetic steel sheet and is formed in a cylindrical shape about an axis O. The stator core 11 is provided to be fixed to an inner peripheral surface of the case 2.
The stator coil 13 is provided so as to be wound around the stator core 11.
Here, an outer diameter of the stator core 11 is defined as ΦMo.
The rotor core 12 is formed of an electromagnetic steel sheet and a magnet and is formed in a columnar shape about the axis O. The rotor core 12 can rotate about the axis O by a power supply to the stator core 11. In the rotor core 12, a through-hole 12a which is formed in a columnar shape about the axis O and penetrates the rotor core 12 in the direction of the axis O is formed. A balance weight 25 (counterweight) is attached to the rotor core 12 in order to prevent run-out of the rotor core 12 when the electric motor 3 is driven. The balance weight 25 is attached to the lower portion of the rotor core 12. The balance weight 25 is formed of stainless steel. The balance weight 25 is not necessarily formed of stainless steel and may be formed of any nonmagnetic material such as a copper alloy or steel.
The rotary shaft 5 is formed in a columnar shape about the axis O and extends in the direction of the axis O along a vertical direction. The rotary shaft 5 is inserted into the through-hole 12a of the rotor core 12, and thus, is fixed to the inner portion of the rotor core 12. Accordingly, a rotational driving force generated by the electric motor 3 is output from the rotor core 12 to the rotary shaft 5.
Here, an outer diameter (≅a diameter of the through-hole 12a) of the rotary shaft 5 is defined as ΦLJ.
The upper bearing 17 and the lower bearing 18 are spaced apart from each other in the direction of the axis O, that is, the vertical direction and are disposed at the lower portion of the case 2. The upper bearing 17 and the lower bearing 18 support the rotary shaft 5 in a cantilever manner such that a first end portion (the upper portion in FIG. 1) of the rotary shaft 5 becomes a free end side and can rotate around the axis O with respect to the case 2. More specifically, the rotary shaft 5 protrudes downward from the rotor core 12 and only a second end portion (the lower portion in FIG. 1) opposite to the first end portion is supported by the upper bearing 17 and the lower bearing 18.
The piston rotor 15 is attached to the second end portion of the rotary shaft 5 to be eccentric to the axis O, and thus, the piston rotor 15 eccentrically rotates according to rotation of the rotary shaft 5.
A compression chamber 19 in which the piston rotor 15 is accommodated and sealed is formed inside the cylinder 16 so as to be interposed between the upper bearing 17 and the lower bearing 18. The suction pipe 10 is connected to the cylinder 16, and a supply flow path 20 through which the refrigerant gas G is supplied into the compression chamber 19 is formed. The piston rotor 15 rotates by the rotation of the rotary shaft 5, a volume of the compression chamber 19 inside the cylinder 16 gradually decreases, and thus, the refrigerant gas G is compressed. The cylinder 16 includes an inner peripheral surface 16a which slides to have a minute clearance between the outer peripheral surface of the piston rotor 15 at one location on the periphery of the cylinder 16 and has a cylindrical surface shape. An axis center of the inner peripheral surface 16a of the cylinder 16 coincides with the axis O. An inner diameter of the inner peripheral surface 16a is the inner diameter ΦDc of the cylinder 16.
Here, the volume of the compression chamber 19 of the cylinder 16 is a volume obtained by subtracting the volume of the piston rotor 15 inside the compression chamber 19 from a volume of a space which has the inner diameter ΦDc of the cylinder 16 as a diameter. The volume of the compression chamber 19 is a so-called cylinder exclusion volume. Accordingly, the cylinder exclusion volume is correlated with the inner diameter ΦDc of the cylinder 16, and the cylinder exclusion volume decreases as the inner diameter ΦDc of the cylinder 16 decreases.
Here, in the present embodiment, the outer diameter ΦMo of the stator core 11 and the inner diameter ΦDc of the cylinder 16 satisfy the following Expression (1). $ΦDc / ΦMo \leq 0.350$
In the present embodiment, the outer diameter ΦMo of the stator core 11 and the inner diameter ΦDc of the cylinder 16 may satisfy the following Expression (2). $ΦDc / ΦMo \leq 0.320$
In the present embodiment, the outer diameter ΦMo of the stator core 11 and the inner diameter ΦDc of the cylinder 16 may satisfy the following Expression (3). $0.200 \leq ΦDc / ΦMo \leq 0.320$
In the present embodiment, the outer diameter ΦLJ of the rotary shaft 5 and the outer diameter ΦMo of the stator core 11 may satisfy the following Expression (4). $ΦLJ / ΦMo \leq 0.140$
In the present embodiment, the outer diameter ΦLJ of the rotary shaft 5 and the outer diameter ΦMo of the stator core 11 may satisfy the following Expression (5). $0.0800 \leq ΦLJ / ΦMo \leq 0.140$
In the present embodiment, the outer diameter ΦLJ of the rotary shaft 5 and the outer diameter ΦMo of the stator core 11 may satisfy the following Expression (6). $0.106 \leq ΦLJ / ΦMo \leq 0.140$
Here, as shown in FIG. 2, it is known that an iron loss (eddy current loss) at the stator core 11 can be reduced as the outer diameter ΦMo of the stator core 11 increases. Accordingly, it is possible to improve the efficiency of the electric motor 3 by increasing the outer diameter ΦMo of the stator core 11.
Moreover, as shown in FIG. 3, under conditions of obtaining predetermined compression capacity by the compressor 1, it is known that it is necessary to increase the number of revolution of the electric motor 3 if the inner diameter ΦDc (the value correlated with the cylinder exclusion volume) of the cylinder 16 decreases. That is, if the inner diameter of the cylinder 16 : D_c1 < D_c2, the number of revolution of the electric motor 3 : rps₂ < rps₁.
As shown in FIG. 4, it is known that a decrease rate of the motor efficiency increases as the number of revolutionof the electric motor 3 moves toward a region of a low number of revolution. Accordingly, if the electric motor 3 is operated at a region of a low number of revolution, the motor efficiency decreases.
Therefore, under conditions of obtaining predetermined compression capacity by the compressor 1, if the inner diameter ΦDc of the cylinder 16 decreases, the number of revolution of the electric motor 3 increases. As a result, as shown in FIG. 5, the efficiency of the electric motor 3 is improved.
By setting the outer diameter ΦMo of the stator core 11 large and (or) setting the inner diameter ΦDc of the cylinder small so as to set the value of ΦDc / ΦMo to 0.350 or less as described in Expression (1), it is found that sufficient efficiency of the electric motor 3 can be obtained even when application to an actual machine is considered.
In the compressor 1 of the present embodiment, the outer diameter ΦMo of the stator core 11 and the inner diameter ΦDc of the cylinder 16 satisfy the above Expression (1): ΦDc / ΦMo ≤ 0.350. In the compressor 1 of the present embodiment, by forming the electric motor 3 and the cylinder 16 such that the value of ΦDc / ΦMo is 0.350 or less, it is possible to improve efficiency of the electric motor 3 and achieve high efficiency of the compressor 1 by a simple method based on a simple index like Expression (1) without significantly changing the installation space or the external shape of the compressor 1.
If the outer diameter ΦMo of the stator core 11 and the inner diameter ΦDc of the cylinder 16 satisfy the above Expression (2): ΦDc / ΦMo ≤ 0.320, it is found that the efficiency of the electric motor 3 can be further improved and further improvement of the efficiency of the compressor 1 can be achieved. Accordingly, in the compressor 1 of the present embodiment, by forming the electric motor 3 and the cylinder 16 such that the value of ΦDc / ΦMo is 0.320 or less, it is possible to achieve further improvement of the efficiency of the compressor 1 without significantly changing the installation space or the external shape of the compressor 1.
When specifications of an actual machine are considered, if the outer diameter ΦMo of the stator core 11 and the inner diameter ΦDc of the cylinder 16 satisfy the above Expression (3): 0.200 ≤ ΦDc / ΦMo s 0.320, it is found that the efficiency of the electric motor 3 can be further improved and further improvement of the efficiency of the compressor 1 can be achieved. Accordingly, in the compressor 1 of the present embodiment, by forming the electric motor 3 and the cylinder 16 such that the value of ΦDc / ΦMo is 0.320 or less and 0.200 or more, it is possible to achieve further improvement of the efficiency of the compressor 1 without significantly changing the installation space or the external shape of the compressor 1.
Here, as shown in FIG. 6, it is known that a sliding loss between the rotary shaft 5 and the upper bearing 17, between the rotary shaft 5 and the lower bearing 18, or the like can be reduced if the outer diameter ΦLJ of the rotary shaft 5 decreases.
Accordingly, it is possible to improve machine efficiency by setting the outer diameter ΦLJ of the rotary shaft 5 small. As described above, it is possible to reduce the iron loss (eddy current loss) at the stator core 11 and improve the efficiency of the electric motor 3 by setting the outer diameter ΦMo of the stator core 11 large. Therefore, by setting the outer diameter ΦLJ of the rotary shaft 5 to be smaller than the outer diameter ΦMo of the stator core 11 and setting the value of ΦLJ / ΦMo to 0.140 or less as described in Expression (4), it is found that sufficient efficiency of the compressor 1 can be obtained even when application to an actual machine is considered.
Accordingly, in the compressor 1 of the present embodiment, by forming the electric motor 3 and the rotary shaft 5 such that the outer diameter ΦLJ of the rotary shaft 5 and the outer diameter ΦMo of the stator core 11 further satisfy the above Expression (4): ΦLJ / ΦMo ≤ 0.140, it is possible to improve efficiency of the electric motor 3 and achieve high efficiency of the compressor 1 by a simple method based on a simple index like Expression (4) without significantly changing the shape, the installation space, or the like of the compressor 1.
Moreover, the rotary shaft 5 which is not formed of an electromagnetic steel sheet is inserted into the rotor core 12 formed of an electromagnetic steel sheet. In the present embodiment, by decreasing the outer diameter ΦLJ of the rotary shaft 5, it is possible to decrease the diameter of the through-hole 12a of the rotor core 12, and thus, it is possible to increase the number of electromagnetic steel sheets in the rotor core 12. Accordingly, it is possible to reduce a magnetic resistance of the rotor core 12, the efficiency of the electric motor 3 can be improved, and high efficiency of the compressor 1 can be achieved.
Here, if the outer diameter ΦLJ of the rotary shaft becomes too small, one-sided contact is likely to occur between the upper bearing 17 and the rotary shaft 5 and between the lower bearing 18 and the rotary shaft 5. Accordingly, it is found that the sliding loss increases in a region where ΦLJ is smaller than a predetermined value, and as shown in FIG. 7, in the value of ΦLJ / ΦMo, the minimum value exists, at which the sliding loss between the upper bearing 17 and the rotary shaft 5 and between the lower bearing 18 and the rotary shaft 5 is smallest. It is found that the minimum value of ΦLJ ΦMo is a value which is 0.0800 or more, 0.0106 or more, and 0.140 or less.
Accordingly, in the present embodiment, when specifications of an actual machine are considered, by forming the rotary shaft 5 and the electric motor 3 such that the outer diameter ΦLJ of the rotary shaft 5 and the outer diameter ΦMo of the stator core 11 further satisfy the above Expression (5): 0.0800 ≤ ΦLJ / ΦMo ≤ 0.140, it is possible to reduce the sliding loss and achieve further improvement of the efficiency of the compressor 1 without significantly changing the installation space or the external shape of the compressor 1.
In the present embodiment, by forming the rotary shaft 5 and the electric motor 3 such that the outer diameter ΦLJ of the rotary shaft 5 and the outer diameter ΦMo of the stator core 11 satisfy the above Expression (6): 0.0106 ≤ ΦLJ / ΦMo ≤ 0.140, it is possible to further reduce the sliding loss and achieve further improvement of the efficiency of the compressor 1 without significantly changing the installation space or the like of the compressor 1.
Hereinbefore, the embodiment of the present invention is described with reference the drawings. However, configurations of the embodiment, combinations thereof, or the like are examples of the present invention, and additions, omissions, substitutions, and other modifications of the configurations can be made within a scope which does not depart from the gist of the present invention. Moreover, the invention is not limited to the embodiment, and is only limited by claims.
For example, in the above descriptions, the sealed rotary compressor 1 is described. However, the above-described configuration may also be applied to a sealed two-stage compressor or the like which further includes a scroll compression mechanism on the upper portion in the case 2.

EXPLANATION OF REFERENCES

1: sealed rotary compressor
2: case
3: electric motor
5: rotary shaft
7: body
8: upper cover
9: bottom cover
10: suction pipe
11: stator core
12: rotor core
12a: through-hole
13: stator coil
14: discharge pipe
15: piston rotor
16: cylinder
16a: inner peripheral surface
17: upper bearing
18: lower bearing
19: compression chamber
20: supply flow path
25: balance weight
O: axis
G: refrigerant gas

Claims

A sealed rotary compressor (1), comprising:
an electric motor (3);

a rotary shaft (5) which is capable of being rotated around an axis (O) by the electric motor (3);

a piston rotor (15) which is provided on the rotary shaft (5) and rotates to be eccentric with respect to the axis (O) according to rotation of the rotary shaft (5);

a cylinder (16) in which a compression chamber (19) in which the piston rotor (15) is accommodated is formed inside the cylinder (16) and a supply flow path (20) through which a refrigerant is supplied to the compression chamber (19) is formed;

a case (2) which surrounds the cylinder (16) to form, between the cylinder (16) and the case (2), a discharge space to which the refrigerant compressed by the piston rotor (15) is exhausted and in which the electric motor (3), the rotary shaft (5), the piston rotor (15), and the cylinder (16) are accommodated in a sealed manner; and

a bearing which supports the rotary shaft (5) to the case (2),

wherein the electric motor (3) includes a rotor core (12) which fixes the rotary shaft (5) to the inner portion of the rotor core (12), a stator core (11) which is fixed to the case (2) on an outer peripheral side of the rotor core (12), and a stator coil (13) which is provided in the stator core (11), and

wherein when an outer diameter of the stator core (11) is defined as ΦMo and an inner diameter of the cylinder (16) is defined as ΦDc, the following Expression (1) is satisfied. $ΦDc / ΦMo \leq 0.350$
The sealed rotary compressor (1) according to claim 1,
wherein when the outer diameter of the stator core (11) is defined as ΦMo and the inner diameter of the cylinder (16) is defined as ΦDc, the following Expression (2) is further satisfied. $ΦDc / ΦMo \leq 0.320$
The sealed rotary compressor (1) according to claim 2,
wherein when the outer diameter of the stator core (11) is defined as ΦMo and the inner diameter of the cylinder (16) is defined as ΦDc, the following Expression (3) is further satisfied. $0.200 \leq ΦDc / ΦMo \leq 0.320$
The sealed rotary compressor (1) according to any one of claims 1 to 3,
wherein when an outer diameter of the rotary shaft (5) is defined as ΦLJ, the following Expression (4) is further satisfied. $ΦLJ / ΦMo \leq 0.140$
The sealed rotary compressor (1) according to claim 4,
wherein when the outer diameter of the rotary shaft (5) is defined as ΦLJ, the following Expression (5) is further satisfied. $0.0800 \leq ΦLJ / ΦMo \leq 0.140$
The sealed rotary compressor (1) according to claim 5,
wherein when the outer diameter of the rotary shaft (5) is defined as ΦLJ, the following Expression (6) is further satisfied. $0.106 \leq ΦLJ / ΦMo \leq 0.140$