JPH11132171A - Helical compressor - Google Patents

Abstract

(57) [Problem] To provide a helical compressor which has a simplified structure, is easy to assemble, and can be reduced in size and size. A helical compressor (15) includes a sealed case (1).
6, a helical compression mechanism 17 and this compression mechanism 17
And an electric motor section 18 for driving the same via a rotating shaft 22. The helical compression mechanism 17 includes a cylinder 24 fixed to the closed case 16, a roller 25 eccentrically disposed in the cylinder 24, and a plurality of compression chambers between the roller 25 and the cylinder 24. 28
And a helical blade 27 that defines the section. The roller 25 is mounted on a crank portion 29 of the rotating shaft 22, while the rotating shaft 22 is rotatably supported by a single bearing 30 that closes one end of the cylinder 24. When the roller 25 revolves or rotates in the cylinder 24 by the drive of the electric motor unit 18, the compression chamber 2 on the other end side of the cylinder is rotated.
The fluid to be compressed sucked into the cylinder 8 is sequentially compressed while moving along the roller axis direction, and is discharged from the compression chamber 28 at one end of the cylinder to the sealed case 16.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a helical compressor for continuously compressing a fluid to be compressed such as a refrigerant in a refrigeration cycle, and more particularly to a helical compressor having an improved compressor assembly structure, a bearing support structure, and a balancer support structure.

[0002]

2. Description of the Related Art A refrigerating cycle such as an air conditioner for indoor air conditioning or a refrigerator or the like is provided with a compressor for compressing a refrigerant. Among these types of compressors, helical compressors employing a helical blade for a motor-driven compression mechanism are being developed.

A conventional helical compressor is configured as shown in FIG. 1, and includes a helical compression mechanism 2 and a motor 4 for driving the compression mechanism 2 via a rotary shaft 3 in a closed case 1. ing. The helical compression mechanism 2 is provided with a cylinder 5 fixed to the sealed case 1, a roller 6 as a rotating body housed at an eccentric position in the cylinder 5, and interposed between the roller 6 and the cylinder 5. And a spiral blade (helical blade) 7 wound around a spiral groove formed on the outer periphery of the roller. A plurality of compression chambers 8 are formed between the cylinder 5 and the roller 6 by a helical blade 7 along the axial direction of the cylinder 5.

[0006] The roller 6 is a crank portion 3 of the rotating shaft 3.
a, the rotary shaft 3 is rotatably supported by a main bearing 9 and a sub-bearing 10 that close both sides of the cylinder 5.

[0005] When the motor section 4 is energized, the motor section 4 is started, the motor rotor 4 a is driven to rotate, and the rotating shaft 3 is rotated. The rotational force of the shaft 3 is transmitted to the crank portion 3a, and causes the roller 6 to eccentrically rotate. Due to the eccentric rotation of the roller 6, the refrigerant sucked into the low pressure side compression chamber 8 of the cylinder 5 is gradually compressed while being moved in a helical manner along the roller axis direction. Then, the air is discharged from the discharge pipe 13 to the outside of the closed case 1 through a gap formed between the closed case 1 and the motor unit 4.

[0006]

In the conventional helical compressor, both sides of the cylinder 5 are hermetically sealed by a main bearing 9 and a sub-bearing 10, and the main bearing 9 and the sub-bearing 10 constitute an output shaft of the motor unit 4. The rotating shaft 3 is rotatably and stably supported.

However, in the conventional helical compressor, the motor unit 4 housed in the closed case 1
Since the helical compression mechanism 3 and the helical compression mechanism 3 are separately installed on the left and right as shown in FIG. 1, there is a problem in increasing the diameter of the sealed case 1 and reducing its size and size.

In the conventional helical compressor, two balancers 11, 12 are mounted on the rotating shaft 3 between the main bearing 9 and the sub-bearing 10 to correct the weight imbalance caused by rotation. Since the balancers 11, 12 of different pieces are respectively attached to both sides of the crank portion 3a of the shaft 3, the number of parts is large, and the balancers 11, 1
The assembling of No. 2 takes time and is complicated and difficult. In particular, when the roller 6 is mounted on the crank part 3a of the rotating shaft 3 and the balancers 11, 12 are inserted into the rotating shaft 3 from both sides of the cylinder 5, the balancers 11, 12 are attached to the rotating shaft 3. This makes it difficult to mount the balancers 11 and 12 stably.

Further, the rotary shaft 3 is stably supported by the main bearing 9 and the sub-bearing 10, but on the other hand, the two bearings 9, 1
If 0 is used, alignment between both bearings 9 and 10 is required,
Extra centering process is required when assembling the compressor,
Had been an issue.

The present invention has been made in view of the above circumstances, and has as its object to provide a helical compressor which has a simplified structure, is easy to assemble, and can be reduced in size and size.

Another object of the present invention is to provide a helical compressor which does not require alignment of a bearing, reduces the number of parts, and simplifies and facilitates an assembling operation.

Still another object of the present invention is to provide a helical compressor in which the electric motor section and the helical compression mechanism section are partially overlapped to reduce the size and size, reduce the vibration of the compression mechanism section, and improve reliability. To provide.

Another object of the present invention is to reduce the number and volume of balancers disposed outside and between bearings to save space, suppress deflection of the rotating shaft, reduce vibration, and improve reliability. To provide a helical compressor that can

[0014]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, a helical compressor according to the present invention has a cylinder disposed in a case and an eccentrically mounted cylinder. A helical compression mechanism comprising: a rotating body disposed therein; and a helical blade defining a plurality of compression chambers between the rotating body and the cylinder along the cylinder axis direction; and rotating the rotating body. Having an electric motor section for eccentric rotation in a cylinder via a shaft,
The rotating shaft is supported by a single bearing, and one end of the cylinder is closed by this bearing. The rotating body is eccentrically rotated by the electric motor unit to move the fluid to be compressed while sequentially compressing the fluid in the cylinder axial direction. That is, it is configured to be.

According to another aspect of the present invention, there is provided a helical compressor according to the present invention, wherein the single bearing closes an electric motor portion side of a cylinder and the electric motor portion is closed. A counterbore portion is formed on the cylinder side of the motor rotor to be constructed, and is extended so that a boss portion of a single bearing is inserted into the counterbore portion.

Further, in order to solve the above-mentioned problems,
In the helical compressor according to the present invention, as described in claim 3, the single bearing is formed integrally with the cylinder.

Furthermore, in order to solve the above-mentioned problem, a helical compressor according to the present invention is such that the other end of the cylinder is fixed to a closed case and is closed. is there.

Still further, in order to solve the above-mentioned problem, in the helical compressor according to the present invention, as set forth in claim 5, the outer diameters of the cylinder and the bearing are determined by a motor stator winding constituting an electric motor section. , And the cylinder and the bearing are arranged in the motor stator winding.

On the other hand, in order to solve the above-mentioned problem, a helical compressor according to the present invention has an annular or sleeve-like shape between the cylinder and the bearing and the motor stator winding. An insulating member is interposed, and as described in claim 7, a blade stopper is provided on a cylinder side of the electric motor unit, and the blade stopper is provided so as not to protrude from an outer peripheral surface of the cylinder. Further, as described in claim 8, a blade stopper is provided on the bearing.

On the other hand, in order to solve the above-mentioned problem, a helical compressor according to the present invention is configured such that the rotating shaft includes a crank portion for supporting a rotating body, while the rotating shaft includes a crank portion for supporting a rotating body. In the present invention, a balancer is provided on the opposite side of the bearing with respect to the crank portion, and as described in claim 10, a balancer is provided on the cylinder side of a motor rotor constituting the electric motor portion.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a helical compressor according to the present invention will be described below with reference to the accompanying drawings.

FIG. 2 is a longitudinal sectional view showing an embodiment of the helical compressor according to the present invention. The helical compressor 15 accommodates a helical compression mechanism 17 and a motor 18 in a cylindrical hermetic case 16 such as a cylinder.

The motor section 18 comprises a motor stator 20 which is press-fitted and fixed in the sealed case 16 and a motor rotor 21 rotatably accommodated in the motor stator 20. The motor rotor 21 rotates on a rotating shaft 22 which is an output shaft. It is mounted on the shaft.

On the other hand, the helical compression mechanism 17 includes a cylinder 24 fixed to the closed case 16 and this cylinder 2.
Roller 25 as a rotating body eccentrically arranged in 4
Between the roller 25 and the cylinder 24,
A spiral blade (helical blade) 27 is accommodated and wound in a spiral blade groove (helical groove) 26 formed on the outer peripheral portion of the roller 25. The helical blade 27 defines a plurality of compression chambers 28 between the cylinder 24 and the roller 25 along the axial direction of the roller 25. The cylinder 24 has an outer peripheral flange-shaped mounting portion 24a, and the closed case 1 is connected through the mounting portion 24a.
Fixed to 6. The groove pitch of the blade groove 26 and the blade pitch of the helical blade 27 are formed so as to gradually decrease in the cylinder axial direction.

The helical blade 27 is formed of an elastic material, a plastic material, or a fluororesin such as Teflon or a fluoroplastic material. Helical blade 2
7 is airtightly contacted with the inner peripheral wall of the cylinder 24, and is relatively slidably accommodated in and out of a helical groove 26 having a rectangular cross section formed on the outer peripheral surface of the roller 25.

The roller 25 of the helical compression mechanism 17 is mounted on a crank 29 of the rotary shaft 22 and is eccentrically inscribed in the cylinder 24. The rotation of the rotation shaft 22 causes the roller 25 to eccentrically rotate in the cylinder. At this time, in consideration of the wear of the helical blade 27, the roller 25 revolves and does not rotate by a general Oldham mechanism (not shown) or the like, but if the problem of the wear of the helical blade 27 is solved. Alternatively, the Oldham mechanism may be eliminated, and the roller 25 may be configured to revolve and revolve.

The rotary shaft 22 is rotatably supported by a single bearing 30 as a main bearing that closes one side of the cylinder 24. The bearing 30 has a boss portion 31 for supporting the rotary shaft 22 protruding on both sides, and the boss portion 31 forms a bearing sliding portion. One side of the boss portion 31 terminates near the crank portion 29 of the rotary shaft 22, and the other side terminates near the motor rotor 21 of the electric motor portion 18. The axial length of the boss portion 31, that is, the length of the bearing sliding portion Is secured. The bearing 30 is integrally formed on one side of the cylinder 24,
It is located between the roller 25 and the motor rotor 21.

In the helical compressor 15, a balancer 33 is provided because the roller 25 is revolved by the rotation of the rotating shaft 22. The balancer 33 is provided integrally or integrally on the opposite side of the bearing 30 with respect to the crank part 29 of the rotating shaft 22, while the balancer 34 is similarly mounted on the cylinder 24 side of the motor rotor 21. Both balancers 33,
34 prevents the weight imbalance caused by the rotation of the rotating shaft 22 and balances the weight.

The outer diameter φD of the cylinder 24 and the bearing 30
_o is the inner diameter φD of the motor stator winding 23 of the motor section 18
_{When the} helical compression mechanism 17 and the electric motor 18 are incorporated in the closed case 16, the cylinder 24 is inserted into the motor stator winding 23 of the electric motor 18.
And a bearing 30 are accommodated. By partially overlapping the electric motor section 18 and the helical compression mechanism section 17, the axial length of the helical compressor 15 can be shortened and the size and size can be reduced.

The other side of the cylinder 24 is closed by a lid plate 36 as an end plate, and the inflow chamber 37 as a suction chamber is formed by the cylinder 24 and the lid plate 36.
Is formed, and the inflow chamber 37 is connected to the low-pressure side compression chamber 28.
Leads to. The inflow chamber 37 has a closed case 1
A suction tube 38 extending through 6 faces.

Each of the compression chambers 28 formed between the cylinder 24 and the roller 25 is connected to the low pressure side compression chamber 2 on the other side of the cylinder.
8 moves in a helical manner along the axial direction of the cylinder 24, the volume changes so that the volume gradually decreases, and the refrigerant as the fluid to be compressed is continuously compressed.
A high-pressure side compression chamber 28 is formed on one side. The refrigerant from the high-pressure side compression chamber 28 is discharged into the closed case 16 through a discharge port 39 formed in the bearing.

Reference numeral 41 denotes lubricating oil as refrigerating machine oil stored in the sealed case 16, and the lubricating oil is supplied to a bearing sliding portion of the rotary shaft 22 by an oil pump mechanism 43. .

Next, the operation of the helical compressor 15 will be described.

The helical compressor 15 is used by being incorporated in a refrigerating cycle of an air conditioner, a refrigerator, a freezing showcase or the like. The helical compressor 15 is started by energizing the electric motor section 18, and the motor rotor 21 is driven to rotate. The rotational force of the motor rotor 21 is transmitted to the crank portion 29 of the rotating shaft 22,
5 is revolved (eccentric rotation).

The rotation of the roller 25 causes the cylinder 2
The refrigerant as the fluid to be compressed is sucked from the inflow chamber 37 into the low pressure side compression chamber 28 formed on the other side of 4. The refrigerant flowing into the low pressure side compression chamber 28 is revolved by the roller 25,
The compression chamber 28 formed by the cylinder 24, the roller 25, and the helical blade 27 is sequentially moved in a helical (spiral) shape along the axial direction of the cylinder 24, and is gradually and continuously compressed during the movement. The compressed refrigerant is discharged from the high-pressure side compression chamber 28 through the discharge port 39 into the closed case 16, and then the inside of the closed case 16 and the motor stator 2
0, or through a gap formed between the motor stator 20 and the motor rotor 21 from the discharge pipe 40 to the outside of the closed case 16.

In the helical compressor 15, the rotating shaft 22 is supported by the single bearing 30 as the main bearing, so that the number of parts can be reduced, and the auxiliary bearing is not required. Alignment is not required and assembly is simplified. Rotating shaft 2
When the bearing 2 is supported by a single bearing 30, the inclination and deflection of the rotary shaft 22 are slightly larger than those of a helical compressor supported by two bearings, a main bearing and a sub bearing. However, in the helical compressor 15, since the differential pressure between the compression chambers 28 formed by the helical blades 27 between the cylinder 24 and the rollers 25 is small, the leakage of the refrigerant is small and there is almost no adverse effect on the compressor performance.

FIG. 3 is a longitudinal sectional view showing a first modification of the embodiment of the helical compressor according to the present invention.

The helical compressor 15A shown in this modification is an improved version of the support structure of the rotary shaft 22, and the other components are not different from the helical compressor 15 shown in FIG. Is omitted.

In the helical compressor 15A shown in the first modification, a counter bore 45 is formed in the motor rotor 21 of the electric motor section 18, and the counter bore 45 is inserted into the boss 31 of the single bearing 30 as a main bearing. It was established.

The motor section 18 has a counterbore section 45 formed at the center of the motor rotor 21 on the cylinder 24 side. The counterbore section 45 forms an annular or sleeve-shaped space between the motor rotor 21 and the rotary shaft 22. Then, the boss portion 31 of the single bearing 30 that supports the rotating shaft 22 is extended toward the motor rotor 21 and inserted into the annulus-shaped space to terminate.
Thereby, the axial length of the boss portion 31 of the bearing 30, that is, the bearing length can be further increased, and the rotating shaft 22 can be stably supported.

In the helical compressor 15A shown in the first modification, the rotating shaft 22 can be rotated more smoothly and stably, and the same operation and effect as the helical compressor 15 shown in FIG. Can be.

FIG. 4 is a longitudinal sectional view showing a second modification of the embodiment of the helical compressor according to the present invention.

The helical compressor 15B shown in this modification is different from the helical compressor 15A shown in FIG. 3 in the support structure of the cylinder 24, and the other components are substantially the same. The description is omitted.

The helical compressor 15B shown in the second modification is a cylinder 24 of the helical compression mechanism 17.
Is directly fixed to the bottom of the sealed case 16. The cylinder 24 is fixed to the closed case 16 and the cylinder 24 is fixed.
By closing on the other side, a lid plate as an end plate becomes unnecessary, and the number of parts can be reduced accordingly.

In the helical compressor 15B shown in the second modification, the rotary shaft 22 can be rotated smoothly and stably, and the same operation and effect as those of the helical compressors 15 and 15A shown in FIGS. 2 and 3 can be obtained. Play.

FIG. 5 is a longitudinal sectional view showing a third modification of the embodiment of the helical compressor according to the present invention.

The helical compressor 15C shown in this modification also has the same basic structure as the helical compressor 15 shown in FIG. 2, so the same components are denoted by the same reference numerals and description thereof will be omitted.

The helical compressor 15C shown in the third modified example is the cylinder 24 of the helical compression mechanism 17.
A blade stopper 46 is provided on the
An annular or sleeve-shaped insulating member 47 is interposed between the cylinder 8 and the cylinder 24 and the single bearing 30.

The helical compressor 15 shown in FIG.
C is a blade stopper 46 on the bearing 30 side of the cylinder 24.
Is provided. As shown in FIG. 6, the blade stopper 46 is held by being held by a blade stopper press 49 in a stopper housing hole 48 of the cylinder 24 to prevent the stopper head of the blade stopper 46 from projecting from the outer peripheral surface of the cylinder 24. ing.

The stopper portion of the blade stopper 46 projects into the cylinder 24 and abuts against the tip of the helical blade 27 to restrict the axial movement of the helical blade 27.

Since the blade stopper 46 and the blade stopper presser 49 are configured so as not to protrude from the outer peripheral surface of the cylinder 24, they can be reliably prevented from coming into contact with the motor stator winding 23, and a highly reliable helical compressor is provided. 15C can be provided.

The insulating member 47 is disposed on the inner peripheral side of the motor-side motor stator winding 23 on the cylinder side, and insulates the motor stator winding 23 from the outer circumference of the cylinder 24 and the bearing 30. Even when the inner circumference of the motor stator winding 23 of the electric motor section 18 is close to the outer circumferences of the cylinder 24 and the bearing 30, a highly reliable helical compressor 15C can be provided without causing insulation failure.

The helical compressor 15C shown in the third modification also has the same operation and effects as those of the helical compressors 15, 15A and 15B shown in FIGS.

FIG. 7 is a longitudinal sectional view showing a fourth modification of the embodiment of the helical compressor according to the present invention.

The helical compressor 15D shown in this modification is one in which a blade stopper 50 is provided on a bearing 30 supporting a rotary shaft 22 in the axial direction by a blade stopper presser 51. The other configuration is not substantially different from that of the helical compressor 15 shown in FIG.

In the helical compressor 15D shown in the fourth modification, a blade stopper 50 is provided on the bearing 30,
The stopper portion of the blade stopper 50 is
The helical blade 27 is restricted from moving in the axial direction by projecting inward and making contact with the tip of the helical blade 27.

By mounting the blade stopper 50 in the axial direction of the bearing 30, it is possible to reliably prevent the blade stopper 50 and the blade stopper retainer 51 from contacting the motor stator winding 23, and to provide a highly reliable helical compressor 15C. it can.

The helical compressor 15D shown in the fourth modification has the same operation and effect as the helical compressors 15, 15A, 15B, and 15C shown in FIGS.

In this embodiment, the helical compressor is described as being of the horizontal type, but may be of the vertical type.

[0060]

As described above, in the helical compressor according to the present invention, the motor section and the helical compression mechanism section can be partially overlapped, and the helical compressor can be reduced in size and size. it can.

According to the first aspect of the present invention, the rotating shaft, which is the output shaft from the electric motor, can be supported by a single bearing, and the need for an auxiliary bearing is eliminated, so that the number of parts is reduced and the structure is simplified. In addition, the centering action between the bearings becomes unnecessary, and the assembling becomes easy.

According to the second aspect of the present invention, even if the output shaft is supported by a single bearing, the bearing length of the bearing (the length of the boss in the axial direction) can be sufficiently ensured, and the rotary shaft can be used. The compressor can be smoothly and stably rotated to improve compressor performance and reliability.

According to the third aspect of the present invention, since the bearing and the cylinder are integrally formed, the number of parts can be reduced, the structure is simplified, and the assembly is facilitated.

According to the fourth aspect of the present invention, since the cylinder is directly fixed to the case bottom of the closed case, an end plate is not required, and the number of parts can be further reduced.

According to the fifth aspect of the present invention, the cylinder and the bearing can be arranged inside the motor stator winding of the electric motor, and the electric motor and the helical compression mechanism can be partially overlapped. The size and size of the helical compressor can be reduced accordingly.

In the invention according to claim 6, since an annular or sleeve-shaped insulating member is interposed between the motor stator winding of the electric motor and the cylinder and bearing, the inner peripheral surface of the motor stator winding has the cylinder and bearing. The insulation distance can be secured even in the case of being close to the outer peripheral surface of the helical compressor, and a highly reliable helical compressor can be provided without causing insulation failure.

In the invention according to claim 7 or 8, since the cylinder or the bearing is provided with the blade stopper, the axial movement of the helical blade can be regulated, and the compressor performance can be effectively maintained without impairing the compressor function. Can be.

According to the ninth aspect of the present invention, since the balancer is provided on the rotating shaft on the opposite side of the bearing with respect to the crank portion, the balancer can eliminate the rotational imbalance and secure the weight balance. Vibration can be reduced and compressor performance can be improved.

According to the tenth aspect of the present invention, the balancer provided on the rotary shaft and the balancer provided on the cylinder side of the motor rotor ensure the weight balance accompanying the rotation of the rotary shaft while shortening the distance between the balancers. Thus, vibration can be reduced and reliability can be improved.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a conventional helical compressor.

FIG. 2 is a longitudinal sectional view showing an embodiment of a helical compressor according to the present invention.

FIG. 3 is a longitudinal sectional view showing a first modification of the embodiment of the helical compressor according to the present invention.

FIG. 4 is a longitudinal sectional view showing a second modification of the embodiment of the helical compressor according to the present invention.

FIG. 5 is a longitudinal sectional view showing a third modification of the embodiment of the helical compressor according to the present invention.

FIG. 6 is an enlarged view of a main part of the helical compressor shown in FIG. 5;

FIG. 7 is a longitudinal sectional view showing a fourth modification of the embodiment of the helical compressor according to the present invention.

[Explanation of symbols]

15, 15A, 15B, 15C, 15D Helical compressor 16 Sealed case 17 Helical compression mechanism 18 Electric motor 20 Motor stator 21 Motor rotor 22 Rotary shaft (output shaft) 23 Motor stator winding 24 Cylinder 25 Roller (rotary body) 26 Spiral Groove (helical groove) 27 blade (helical blade) 28 compression chamber 29 crank part 30 main bearing (single bearing) 31 boss part (bearing sliding part) 33 balancer 34 balancer 36 lid plate 37 inflow chamber 38 suction pipe 39 spout Outlet 40 Discharge pipe 41 Lubricating oil 45 Counter bore 46, 50 Blade stopper 49, 51 Blade stopper restraint

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Takuya Hirayama 70, Yanagicho, Kochi-ku, Kawasaki-shi, Kanagawa Prefecture Inside the Toshiba Yanagimachi Plant Co., Ltd. (72) Inventor Hiroyuki Mizuno 3-3-9, Shimbashi, Minato-ku, Tokyo Toshiba Abu.E.

Claims (10)

[Claims] 1. A cylinder arranged in a case, a rotating body eccentrically arranged in the cylinder, and a plurality of compression chambers defined between the rotating body and the cylinder along the cylinder axial direction. A helical compression mechanism unit having a helical blade; and an electric motor unit for eccentrically rotating the rotating body in a cylinder via a rotating shaft. The rotating shaft is supported by a single bearing. A helical compressor, wherein one end of a cylinder is closed by a bearing, and the rotating body is eccentrically rotated by the electric motor unit so that the fluid to be compressed is moved while being sequentially compressed in the cylinder axial direction. 2. The single bearing closes a motor portion side of a cylinder, forms a counter bore portion on a cylinder side of a motor rotor constituting the motor portion, and a boss portion of the single bearing is formed on the counter bore portion. The helical compressor according to claim 1, wherein the helical compressor is extended so as to be inserted. 3. The helical compressor according to claim 1, wherein the single bearing is formed integrally with a cylinder. 4. The cylinder according to claim 1, wherein the other end of the cylinder is fixed to a closed case and closed by the closed case.
The helical compressor according to 1. 5. An outer diameter of the cylinder and the bearing is formed to be smaller than an inner diameter of a motor stator winding constituting an electric motor portion, and the cylinder and the bearing are arranged in the motor stator winding. 3. The helical compressor according to 3. 6. The helical compressor according to claim 5, wherein an annular or sleeve-shaped insulating member is interposed between the cylinder and the bearing and the motor stator winding. 7. The helical compressor according to claim 5, wherein a blade stopper is provided on a side of the cylinder on the motor side, and the blade stopper is provided so as not to protrude from an outer peripheral surface of the cylinder. 8. The helical compressor according to claim 5, wherein said bearing is provided with a blade stopper. 9. The helical compressor according to claim 1, wherein the rotary shaft has a crank portion that supports a rotating body, and the rotary shaft has a balancer on a side opposite to a single bearing with respect to the crank portion. 10. The helical compressor according to claim 1, wherein a balancer is provided on a cylinder side of a motor rotor constituting the electric motor section.