JP3412220B2 - Hermetic electric compressor - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hermetic electric compressor such as a scroll compressor or a rotary compressor used for a cooling / heating device or a refrigerator. [0002] Conventionally, hermetic electric compressors such as scroll compressors and rotary compressors have been used for cooling devices such as cooling and heating devices and refrigerators. As a prior art of this kind of compressor, a hermetic electric compressor disclosed in Japanese Patent Application Laid-Open No. 60-50996 will be described with reference to the drawings. [0004] As shown in FIG. 4, in a closed container 101, the rotational force of a compression mechanism 102, a rotor 104 and a stator 105 constituting a motor section 103, and the torque of the motor section 103 are transmitted to the compression mechanism section 102. And a bearing member 107 for supporting the crankshaft 106 are provided. The closed vessel 101 has a suction pipe 108 for sucking low-pressure refrigerant gas, and a discharge pipe 1 for discharging high-pressure refrigerant gas compressed by the compression mechanism 102 to the outside of the closed vessel.
09 is provided. In the above configuration, when the rotor 104 of the electric motor section 103 rotates, this rotational force is applied to the crankshaft 106.
Is transmitted to the compression mechanism 102. Compression mechanism 1
When the rotational force is transmitted to 02, a compression action occurs. As a result, the low-pressure refrigerant gas sucked from the suction pipe 108 is compressed into a high-pressure refrigerant gas by the compression mechanism unit 102, and is once discharged into the discharge port side space 113 of the internal space of the closed container 101, and then the bearing member After passing through the communication hole 111 provided in the motor 107 and flowing into the motor-side space 114 in which the motor 103 is provided, the discharge pipe 109 mainly passes through between the bearing member 107 and the motor 103. It is discharged to a refrigeration cycle (not shown). Further, a lubricating oil reservoir 110 is provided at a lower portion of the closed vessel 101. The lubricating oil stored in the lubricating oil reservoir 110 is pumped up by a lubrication pump (not shown) or the like, passes through a through hole 112 provided in the crankshaft 106, and passes through the compression mechanism 102 and the bearing member 107. After lubricating the sliding surface of the crankshaft 106 and the like, a part thereof is discharged from the compression mechanism 102 together with the high-pressure refrigerant gas into the internal space of the closed container 101, and the rest falls from the bearing member 107 by the action of gravity, It returns to the lubricating oil reservoir 110 at the lower part of the closed container 101. However, in the compressor having the above-described structure, after the high-pressure refrigerant gas compressed by the compression mechanism is discharged into the internal space of the closed container, the compressor mainly has a bearing member. And the motor section, the gas is discharged from the discharge pipe to the outside of the closed vessel, so that there are few machines in which the high-pressure refrigerant gas comes into contact with the motor section. That is, the motor section is not sufficiently cooled by the high-pressure refrigerant gas. Therefore, when the compressor is operated at a high speed or under a high load, a large current flows through the stator of the electric motor unit, and the stator generates abnormal heat due to the resistance of the stator wire itself. As a result, the deterioration of the insulator covering the conductor of the stator progresses, and the insulation is reduced. As a result, the stator may be destroyed, and eventually the compressor may be damaged. The high-pressure refrigerant gas compressed by the compression mechanism is discharged into the internal space of the closed vessel and then passes mainly between the bearing member and the electric motor. Will intersect with the flow path. Therefore, the high-pressure refrigerant gas captures a large amount of the lubricating oil falling from the bearing member, and is discharged from the discharge pipe to the outside of the sealed container together with the lubricating oil. In particular, by operating the compressor at high speed,
Increasing the refrigerant discharge rate significantly increases the ratio of the weight of the lubricating oil to the weight of the refrigerant to be discharged. in this way,
As the amount of lubricating oil discharged from the compressor to the refrigeration cycle increases, the pipe pressure loss in the refrigeration cycle increases.
In addition, since the heat exchange efficiency in heat exchangers such as condensers and evaporators is reduced, even if the compressor is operated at high speed, the refrigerating capacity does not increase, or the coefficient of performance of the refrigeration cycle decreases. Had. The present invention solves the above-mentioned problems of the prior art, and sufficiently cools the stator with high-pressure refrigerant gas even when the temperature of the stator of the motor increases during high load or high speed operation of the compressor. It is another object of the present invention to provide a compressor having high reliability and a high coefficient of performance by suppressing the amount of lubricating oil discharged from the compressor to the refrigeration cycle. Means for solving the above problems are as follows. In order to temporarily receive the lubricating oil after lubricating the compression mechanism, a lubricating oil receiver having a small hole is installed between the compression mechanism and the electric motor, and hermetically sealed from the discharge port of the compression mechanism. The high-pressure refrigerant gas discharged into the discharge port side space of the inner space of the container passes through the communication hole communicating the discharge port side space and the motor side space, and then flows into the motor side space. The main flow of gas passes through a notch provided substantially coaxially with the communication hole on the outer peripheral portion of the stator constituting the motor portion, and passes below the stator to form the stator and the motor portion. After passing through a gap with a rotor integrally attached to the crankshaft and a notch other than a notch of a stator provided substantially coaxially with the communication hole, the lubricating oil receiver is provided. The crankshaft is rotating It is obtained so as to be discharged to the outside from the discharge pipe of the closed container provided in an angle close to about 180 degrees relative to the axis. A compression mechanism, an electric motor for driving the compression mechanism below the compression mechanism, and a rotational force of the electric motor are transmitted to the compression mechanism in the closed container. And a lubricating oil reservoir at a lower portion in the closed container, and lubricating oil stored in the lubricating oil reservoir lubricated a sliding portion of the compression mechanism through a through hole provided in the crankshaft. Thereafter, a lubricating oil receiver provided between the compression mechanism portion having a small hole and the electric motor portion for temporarily receiving the motor is installed, and the internal space of the closed container is reduced by the electric motor by the compression mechanism portion. Section is divided into a motor side space in which a section is installed and a discharge port side space in which a discharge port of the compression mechanism section is provided, and a communication hole for communicating the motor side space and the discharge port side space is provided. And the position of the communication hole is The rotation center axis of the tank axis, is obtained by substantially the same angle as the small holes provided in receiving the lubricant. [0013] Further, the height of the lower end of the outer periphery of the compression mechanism is lower than the height of the upper end of the stator. The operation of the above means is as follows. After the high-pressure refrigerant gas containing the lubricating oil compressed by the compression mechanism is discharged to the discharge port side space of the closed container interior space, a communication hole for communicating the discharge port side space with the motor side space. , A downward flow is generated with respect to the closed container. For this reason, the mainstream of high-pressure refrigerant gas is
Passing through a notch on the outer periphery of the stator provided substantially coaxially with the communication hole, passing below the stator, providing a gap between the stator and the rotor, and provided substantially coaxially with the communication hole. Pass through a notch other than the cutout of the stator. During this time, the flow rate of the high-pressure refrigerant gas decreases, and the chance of contact with the inner surface of the closed container and the stator increases, so that the lubricating oil contained in the high-pressure refrigerant gas is removed from the inner surface of the closed container and fixed by the action of surface tension. It grows in a drop shape on the surface of the child, and falls under the closed container by the action of gravity. As a result, most of the high-pressure refrigerant gas and the lubricating oil are separated. Further, since the high-pressure refrigerant gas flows around the electric motor section as described above, the chance of contact between the high-pressure refrigerant gas and the electric motor section is increased.
The motor section can be sufficiently cooled. That is, even when the temperature of the stator of the electric motor section rises when the compressor is operated at high speed, the stator can be sufficiently cooled by the high-pressure refrigerant gas, and the abnormal rise in temperature is suppressed. be able to. Further, by setting the lower end of the outer periphery of the compression mechanism at a position lower than the height of the upper end of the stator, the main flow of the high-pressure refrigerant gas flowing into the motor-side space from the communication hole is:
Since it becomes easier to flow into the notch on the outer periphery of the stator provided substantially coaxially with the communication hole, the operation described above can be obtained more reliably. The high-pressure refrigerant gas that has passed through the gap between the rotor and the stator is provided at an angle close to 180 degrees with respect to the central axis of the crankshaft with respect to the small hole provided in the lubricating oil receiver. Since it is discharged to the outside from the discharge pipe of the closed container,
Lubricating oil flowing down from small holes provided in the lubricating oil receiver,
The flow of the high-pressure refrigerant gas discharged to the outside from the discharge pipe of the closed container is substantially 180 degrees with respect to the rotation center axis of the crankshaft.
It will be in the opposite position. Therefore, the high-pressure refrigerant gas hardly captures the lubricating oil. As a result, the proportion of lubricating oil contained in the high-pressure refrigerant gas discharged from the discharge pipe of the closed vessel to the outside is extremely small, increasing the pipe pressure loss during the refrigeration cycle and exchanging heat in condensers and evaporators. It does not cause a situation such as a decrease in heat exchange efficiency in the vessel. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a hermetic electric compressor according to an embodiment of the present invention will be described with reference to the drawings, taking a hermetic electric scroll compressor as an example. In FIG. 1A, a compression mechanism 1 comprises a fixed scroll 3 having a fixed spiral blade 2, a orbiting scroll 6 in which a orbiting spiral blade 4 is formed on a orbiting end plate 5, and an Oldham ring 8. The fixed scroll 2 is fixed to the closed container 10 together with the bearing member 9. An orbiting scroll shaft 7 is provided on the surface of the orbiting scroll 4 opposite to the orbiting scroll blades 4 of the orbiting scroll 5, and the orbiting scroll shaft 7 is rotatable by the bearing member 9 and the sub-bearing member 11. It is fitted into an eccentric hole 13 formed at one end of the supported crankshaft 12. An electric motor unit 16 including a stator 14 fixed to the closed casing 10 and a rotor 15 fixed to the crankshaft 12 and rotatable with the crankshaft 12 is disposed between the bearings 9 and 11. I have. Accordingly, by driving the electric motor unit 16, the crankshaft 12 rotates, and the eccentric hole 13 of the crankshaft 12 performs eccentric rotation. As a result, the orbiting scroll 6 attempts to rotate, but since the rotation is restricted by the Oldham ring 8, the orbiting with the radius between the crankshaft 12 and the orbiting scroll shaft 7 of the orbiting scroll 6 as a radius. Perform exercise. As a result, a plurality of compression working spaces 17 formed by engaging the fixed scroll blades 2 of the fixed scroll 3 and the revolving scroll blades 4 of the revolving scroll 6 while rotating them 180 degrees with each other.
The low pressure refrigerant gas sucked from the suction pipe 18 attached to the closed container 10 is supplied to the suction port 1 provided in the compression mechanism 1.
The compression work is continuously performed as the volume of the compression work space 17 decreases. The compressed high-pressure refrigerant gas is supplied to a discharge port 2 provided in the compression mechanism 1.
From 0, it is discharged to the discharge side space 29 of the internal space of the closed container 10. The internal space of the sealed container 10 is
Thus, the discharge port side space 29 in which the discharge port 20 is provided and the electric motor side space 30 in which the electric motor unit 16 is installed are partitioned by the communication hole 21. Have been. Therefore, when the high-pressure refrigerant gas discharged into the discharge port side space 29 passes through the communication hole 21 of the compression mechanism unit 1 provided in the up-down direction with respect to the closed container 1 and thereafter flows into the motor side space 30 Is directed downward with respect to the closed container 10. Motor unit 1
In the outer periphery of the stator 14, a notch 22 is provided substantially coaxially with the communication hole 21 in the vertical direction with respect to the sealed container 10. Accordingly, the main flow of the downward high-pressure refrigerant gas passes through the notch 22 and reaches the lower part of the closed container 10. After that, the main flow of the high-pressure refrigerant gas passes through the lower part of the stator 14, passes through the gap between the stator 14 and the rotor 15 of the electric motor unit 16, and finally closes from the discharge pipe 23 provided in the closed container 10. It is discharged to the outside of the container 10. On the other hand, a lubricating oil pump 24 is provided at the lower end of the crankshaft 26.
With the rotation of the crankshaft 12, the lubricating oil stored in the lubricating oil sump 25 at the lower part of the closed container 10 is transferred to the crankshaft 1.
2 Through the crankshaft communication hole 26 provided at the center,
It is pumped to the compression mechanism 1 above the closed container 10. And after lubricating each sliding part of the compression mechanism part 1, a part
The high-pressure refrigerant gas is discharged from the discharge port 20 of the compression mechanism 1 to the discharge-side space 29, and most of the remainder is temporarily stored in the lubricating oil receiver 27, and then, as shown in FIG. 10 through a small hole 28 of the lubricating oil receiver 27 provided at an angle close to 180 degrees with respect to the rotation center axis of the crankshaft 26 with respect to the discharge pipe 23 provided by Falling to the bottom of the container 10,
It is stored again in the lubricating oil reservoir 25. According to the above-described embodiment, the main flow of the high-pressure refrigerant gas flowing into the motor side space 30 from the discharge port 20 of the compression mechanism 1 has a long path until it is discharged to the outside of the closed casing 10, so that the flow velocity thereof is The lubricating oil contained in the high-pressure refrigerant gas is reduced by the action of the surface tension because of a sufficient decrease and the chance of contact with the inner wall surface of the closed container 10 and the stator 14 increases. It grows in the form of drops on the surface such as 14, drops by the action of gravity below the closed container 10, and accumulates in the lubricating oil reservoir 25 at the bottom of the closed container 10.
As a result, most of the high-pressure refrigerant gas and the lubricating oil are separated. Further, the main flow of the high-pressure refrigerant gas is different from the main flow of the high-pressure refrigerant gas in the motor-side space 30 because the main flow of the high-pressure refrigerant gas is different from the main flow of the high-pressure refrigerant gas in the motor-side space 30. It rarely catches the lubricating oil falling from the hole 28. Therefore, finally, the closed container 1
The lubricating oil is hardly contained in the high-pressure refrigerant gas discharged to the outside. Further, since the high-pressure refrigerant gas flows around the motor section 16 as described above, the motor section 16 can be sufficiently cooled by the high-pressure refrigerant gas. In another embodiment, as shown in FIG. 2, a communication hole 21 for communicating a motor side space 30 and a discharge port side space 29 is provided with a lubricating oil with respect to the rotation center axis of the crankshaft 12. It is located at substantially the same angle as the small hole 28 provided in the receiver 27. According to the above embodiment, the lubricating oil falling from the small holes 28 of the lubricating oil receiver 27 flows downward from the communication holes 21 into the motor-side space 30 due to the gravity action. As a result, the force of pulling the oil is further increased, so that the oil is not scattered on the way from the small hole, and falls down to the lubricating oil reservoir 25 below the closed container 10 without fail and accumulates again. In FIG. 3, the height of the lower end near the outer periphery of the compression mechanism 9 is lower than the height of the upper end of the stator 14 constituting the motor unit 16. As a result, the main flow of the high-pressure refrigerant gas that has passed through the communication hole 21 and flowed into the motor-side space 30 is more likely to flow into the notch 22 provided in the stator 14. Accordingly, the effect of separating the high-pressure refrigerant gas and the lubricating oil and the effect of cooling the electric motor unit 16 as described above are further ensured. In the above-described embodiment, an example of the hermetic electric scroll compressor has been described. However, the present invention is not limited to the scroll compressor, but may be other hermetic electric compressors, for example, hermetic rotary compressors. Needless to say, it applies to the machine. According to the present invention, as is apparent from the above description,
Since it has the effect of sufficiently cooling the stator of the motor,
When the compressor is operated at a high speed or under a high load, even if the temperature of the stator of the electric motor increases, the stator can be sufficiently cooled by the high-pressure refrigerant gas, and the abnormal increase in the temperature does not occur. Can be suppressed. Further, since the ratio of the lubricating oil contained in the high-pressure refrigerant gas discharged to the outside from the discharge pipe of the closed vessel can be extremely reduced, an increase in piping pressure loss in the refrigeration cycle, a condenser, an evaporator, etc. Thus, it is possible to provide a compressor having high reliability and a high coefficient of performance without causing such a situation that the heat exchange efficiency in the heat exchanger is reduced.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 (a) is a longitudinal sectional view of a hermetic scroll compressor according to an embodiment of the present invention, and FIG. 1 (b) is a schematic transverse sectional view for explaining the same positional relationship. FIG. 3 is a schematic cross-sectional view for explaining a positional relationship in another embodiment of the present invention. FIG. 3 is a partial longitudinal sectional view of a closed scroll compressor in another embodiment of the present invention. FIG. 4 is a conventional closed scroll. Cross-sectional view of compressor [Description of reference numerals] 1 Compression mechanism 9 Bearing member 10 Sealed container 12 Crankshaft 14 Stator 15 Rotor 21 Communication hole 22 Notch 25 Lubricating oil reservoir 27 Lubricating oil receiver 28 Small hole

Continuing on the front page (72) Inventor Masahiro Tsubagawa 1006 Kazuma Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Inventor Toshiharu Yasu 1006 Oji Kadoma Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd. (56 References JP-A-4-370384 (JP, A) JP-A-3-43596 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) F04C 29/00-29/04 F04C 18/00-18/02

Claims (1)

(1) A compression mechanism and an electric motor connected by a crankshaft are housed in an airtight container such that the compression mechanism faces upward, and the crankshaft has one end. A lubricating oil reservoir in which a part is the compression mechanism part and the other end is supported by a sub-bearing provided below the electric motor part, and a tip of the crankshaft on the side opposite to the compression mechanism is immersed in the bottom of the closed casing. Is formed,
The crankshaft is provided with a through-hole communicating the lubricating oil reservoir and the compression mechanism, and the inside of the hermetic container is a motor-side space for accommodating the motor by the compression mechanism and a discharge port where the discharge port of the compression mechanism is opened. And a communication hole communicating with the discharge port side space and the motor side space is provided in an outer peripheral portion of the compression mechanism portion, and an outer peripheral portion of a stator constituting the motor portion is axially penetrated. At least one of the notches is disposed coaxially with the communication hole, a discharge pipe is provided between the compression mechanism section and the electric motor section of the closed container, and a discharge port space is provided from the compression mechanism section. The main flow of the refrigerant gas discharged to the motor passes through the communication hole provided on the outer periphery of the compression mechanism and the motor stator outer peripheral notch arranged coaxially with the communication hole, and reaches the lower portion of the motor, and then the gap and the communication hole of the motor. Not coaxial A hermetic electric compressor that flows upward through the motor through a stator outer notch and is discharged from the discharge pipe to the outside. The hermetic electric compressor is supplied from the lubricating oil reservoir to a compression mechanism through a through-hole in a crankshaft and lubricated. After being provided to the compression mechanism, a lubricating oil receiver that receives all lubricating oil discharged downward and temporarily stores the lubricating oil is provided closely below the compression mechanism, and the lubricating oil receiver has a small gap between the lubricating oil receiver and the crankshaft. A hermetic electric compressor having a small hole for discharging lubricating oil at substantially the same angular position as that of the communication section with respect to the center of rotation of the crankshaft.