JP2003155990A - Compressor for ammonia refrigerant - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inexpensive hermetic compressor for ammonia refrigerant having high reliability and dispensing with special protection and an expensive material in an electric motor and a terminal part even if ammonia refrigerant is used. SOLUTION: In this hermetic compressor for ammonia refrigerant which is provided with an electric motor part composed of a rotor and a stator and a compression mechanism part arranged inside a sealed vessel and uses ammonia as refrigerant fluid, a bulkhead of the sealed vessel if provided between the rotor and the stator in the electric motor part, the rotor is provided in the sealed vessel, and the stator is provided in outside air atmosphere outside of the sealed vessel.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a compressor used in an air conditioner or a refrigerating apparatus, and more particularly to a hermetic compressor for ammonia refrigerant suitable for using ammonia as a refrigerant.

[0002]

2. Description of the Related Art CFC-based refrigerants that have been conventionally used cause destruction of the ozone layer of the earth and global warming. Therefore, the use of natural refrigerants such as ammonia has been studied. However, ammonia has flammability and toxicity, and is highly corrosive, so that it cannot be used with a copper wire or an organic insulating material.

As a compression device using an ammonia-based refrigerant, a compression mechanism unit and an electric motor unit are coupled by a coupling,
A mechanical shaft seal device is used for the rotary shaft of the compression mechanism to prevent the refrigerant from leaking between the rotary shaft and the machine body, and to shut off the outside air. However, it is difficult to completely prevent the refrigerant gas from leaking and shut off from the outside air, and the mechanical loss is large.

Recently, as disclosed in Japanese Unexamined Patent Publication No. 2000-83339, a hermetically sealed structure in which a rotating machine and an electric motor unit are integrated, high-purity aluminum is used for the winding of the electric motor, and What is coated with a fluorine resin which is chemically stable against ammonia, and JP-A-10-
As disclosed in Japanese Patent No. 112949, a compression device in which a compression mechanism section and a bare electric motor are housed in a closed container,
Insulating each part of the electric motor with resin material, and immersing the winding formed by using nickel-plated copper wire or tin-plated copper wire for the winding wire of the electric motor in ether-type lubricating oil compatible with ammonia It is known that a direct contact with ammonia can be blocked by doing so.

[0005]

In the above-mentioned publicly known technology, development of a hermetic compressor centering on a screw type or a rotary type has been studied. However, in the conventional hermetic type compressor, the winding of the electric motor is It is difficult to cool the electric motor part because it requires a covering material to protect it from heat and a molding material to suppress vibration.In particular, ammonia refrigerant has a higher discharge refrigerant temperature than conventional CFC refrigerants. There is a risk that the electric motor may be burnt out in the structure in which is the high pressure space.

Further, an aluminum electric wire resistant to ammonia has a lower conductivity than a copper wire, and the amount of heat generated by the windings of the electric motor increases correspondingly, which causes a problem in cooling the electric motor section.
Further, since the fluorine resin as the coating material has excellent releasability and non-adhesiveness, the adhesion to the winding is poor and there is a risk of burning the electric motor part.

It is an object of the present invention to provide a reliable and inexpensive hermetic compressor for ammonia refrigerant which does not require special protection or expensive materials for the motor and terminals even when using ammonia refrigerant. It is in.

[0008]

In order to achieve the above object, the ammonia refrigerant compressor according to the present invention is characterized by what is stated in each of the claims, but is particularly independent. A compressor for ammonia refrigerant according to the invention as claimed in claim 1 comprises an electric motor section consisting of a rotor and a stator, and a compression mechanism section arranged inside a hermetically sealed container, and uses ammonia as a refrigerant fluid. In the hermetic compressor for ammonia refrigerant using, a partition wall of the hermetic container is provided between the rotor and the stator of the electric motor unit, the rotor is in the hermetic container, and the stator is It is characterized by being installed in an outside air atmosphere outside a closed container.

[0009]

In the compressor of the present invention, the partition wall of the hermetic container is provided between the rotor and the stator of the electric motor, and the rotor is installed in the hermetic container and the stator is installed in the outside air atmosphere outside the hermetic container. It is possible to configure a hermetic compressor for ammonia refrigerant by using a copper wire electric motor that does not have a special coating that prevents contact with the ammonia refrigerant. In addition, the electric motor can be reliably cooled by installing the stator in the ambient atmosphere.

The partition wall of the hermetically sealed container provided between the rotor and the stator of the electric motor is tightly adhered to the inner surface of the stator, so that the rigidity of the stator is high, so that the pressure resistance strength can be secured even with a thin plate. Furthermore, by filling the insulating material in the slots of the stator, it is possible to prevent deformation of the closed container in the slot gaps and prevent fatigue failure.

By constructing the compression mechanism section with a scroll, it is possible to provide a highly efficient compressor with little vibration. In the present invention, the configuration of the low-pressure space around the rotor of the electric motor,
Both configurations of high pressure space are possible.

Further, by adopting a DC brushless electric motor as the electric motor, heat generation of the motor can be reduced, and a more efficient compressor can be provided.

Further, by providing the radiation fins on the outer periphery of the casing supporting the stator of the electric motor, it becomes possible to promote the cooling of the stator.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the scroll compressor according to the present invention will be described below with reference to FIGS.

FIG. 1 is a sectional view of a scroll compressor which is a first embodiment. Inside the hermetic container 7, a compression mechanism unit 10 is arranged on the upper side, and a rotor 802 of the electric motor unit is arranged on the lower side via a rotary shaft 6. The rotor 802 is a rotor of a DC brushless motor incorporating a permanent magnet inside. The closed container 7 includes an upper cap 711, a casing 712, and connecting partition walls 714 and 714 connected to the stator 801.
716, 7 of the partition wall between the stator 801 and the rotor 802
15 and the lower cap 713.

Therefore, the compression mechanism 10 and the rotor 80
2 is disposed inside the closed container 7, and the stator 80
1 is arranged outside the closed container 7. Stator 801
The surrounding space of is communicated with the outside air through a communication hole 717. Radiating fins 718 are provided on the outer peripheral portion of the stator 801.

In the compression mechanism section 10, the fixed scroll 1 and the orbiting scroll 2 constitute a compression mechanism. The ammonia refrigerant is sucked into the compression mechanism section 10 through the suction port 701, compressed, discharged from the discharge hole 101 of the fixed scroll 1 into the closed container 7, and discharged from the discharge port 702 to the outside of the compressor. The rotor 802 is in contact with the high-pressure ammonia refrigerant, but does not use a copper wire, so there is no problem. The stator 801 does not contact with the ammonia refrigerant, so that a copper wire can be used as an electric wire to protect it from the ammonia refrigerant. No coating is required.

Also, since the terminal portion 9 does not come into contact with the ammonia refrigerant, no special protection is required. Further, since the stator 801 is arranged in the atmosphere of the outside air, it is cooled by the outside air. In addition, since the DC brushless electric motor has high efficiency and generates a small amount of heat, a highly efficient compressor can be provided. The heat radiation fins 718 are intended to further promote the heat radiation of the stator 801.

FIG. 2 is a detailed cross-sectional view of a connecting portion between the stator 801 and the partition wall 715 of the closed container 7. The partition wall 715 of the closed container 7 is provided in close contact with the inner surface of the stator 801. An insulating material is filled in the space around the electric wire 804 in the slot 805 so that the partition wall 715 of the closed container 7 does not deform in the radial direction. Since the stator 801 has high rigidity, even if the partition wall 715 of the closed container 7 is a thin plate, pressure resistance can be ensured and fatigue failure can be prevented.

FIG. 3 is a detailed vertical cross-sectional view of the connection portion between the stator 801 and the connection partition walls 714 and 715 of the closed container 7. (a) is a slot part, (b) is a longitudinal cross-sectional view between slots. A support member 803 of the connection partition wall 714 of the closed container 7 is provided at an end of the laminated steel plate 806, and the partition wall 715 of the closed container 7 and the connection partition wall 714 are connected by welding. The plate thickness of the connection partition wall 714 of the closed container 7 is sufficiently thicker than the partition wall 715 in order to secure pressure resistance by itself. The peripheral gap of the electric wire 804 in the slot 805 is filled with the insulating material as described above.

FIG. 4 is a sectional view of a scroll compressor according to the second embodiment. In this embodiment, the suction port 701 is provided in the casing 712, and the discharge port 702 is connected to the upper cap 711.
The low pressure space is provided in the surrounding space of the rotor 802. Also in this embodiment, the stator 80
Since No. 1 does not come into contact with the ammonia refrigerant, a copper wire motor can be used without requiring a special coating.

[0022]

According to the present invention, it is possible to provide a highly reliable and inexpensive compressor for ammonia refrigerant which does not require special protection or expensive materials for the purpose of an ammonia resistant refrigerant in the electric motor and the terminal portion. Is possible.

[Brief description of drawings]

FIG. 1 is a first embodiment of the present invention, showing a cross-sectional view of a scroll compressor.

FIG. 2 is a first embodiment of the present invention, showing a cross-sectional view of a connecting portion between a stator and a closed container.

FIG. 3 is a first embodiment of the present invention and shows a vertical cross-sectional view of a connecting portion between a stator and a closed container.

FIG. 4 is a second embodiment of the present invention and is a sectional view of a scroll compressor.

[Explanation of symbols]

1 ... Fixed scroll 101 ... Discharge hole 2 ... Orbiting scroll 3 ... frame 4 ... Bearing 5 ... Bearing 6 ... Rotary axis 7 ... Airtight container 701 ... Intake port 702 ... Discharge port 711 ... Upper cap 712 ... Casing 713 ... Lower cap 714 ... Connection partition 715 ... Partition wall 716 ... Connection partition 717 ... Communication hole 718 ... Radiating fin 801 ... Stator 802 ... rotor 803 ... Support member 804 ... Electric wire 805 ... slot 806 ... Laminated steel plate 9 ... Terminal 10 ... Compression mechanism section

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H02K 5/18 H02K 5/18 29/00 29/00 Z (72) Inventor Toshinori Yasunori Muramatsu Shimizu, Shizuoka Prefecture Address 390 Hitachi, Ltd. Air conditioning system Shimizu Production Division F-term (reference) 3H029 AA02 AA14 AB03 BB12 BB50 CC07 CC09 CC27 3H039 AA06 BB13 CC11 CC32 CC33 5H019 CC03 EE13 FF01 5H605 AA17 BB07 BB10 BB17 CC10 DD37

Claims (8)

[Claims] 1. An electric motor section comprising a rotor and a stator,
A hermetic compressor for ammonia refrigerant, comprising: a compression mechanism section disposed inside a hermetic container, wherein ammonia is used as a refrigerant fluid, wherein the hermetic seal is provided between the rotor and the stator of the electric motor section. Provide a partition wall of the container, the rotor in the closed container,
A hermetic compressor for ammonia refrigerant, characterized in that the stator is installed in an outside air atmosphere outside the hermetic container. 2. The hermetic compressor for ammonia refrigerant according to claim 1, wherein the partition wall of the hermetic container is brought into close contact with the inner surface of the stator of the electric motor unit. 3. The slot of the stator of the electric motor unit is filled with an insulating material to eliminate a gap between the partition wall of the hermetic container and the stator. A hermetic compressor for ammonia refrigerant. 4. The hermetic compressor for ammonia refrigerant according to claim 1, wherein a scroll compression mechanism is used in the compression mechanism section. 5. The hermetic compressor for ammonia refrigerant according to claim 1, wherein a low pressure space is provided around the rotor of the electric motor section. 6. The hermetic compressor for ammonia refrigerant according to claim 1, wherein a high-pressure space is provided around the rotor of the electric motor section. 7. The hermetic compressor for ammonia refrigerant according to claim 1, wherein a DC brushless electric motor is used in the electric motor section. 8. A hermetic compressor for ammonia refrigerant according to claim 1, wherein a heat radiation fin is provided on an outer periphery of a casing that supports the stator of the electric motor unit.