JPH07174084A - Sealed type compressor - Google Patents

Abstract

PURPOSE:To allow the oil separated from the compressed fluid to recirculate to a pump part in a stable manner, without using the means such as an oil supply pump. CONSTITUTION:The fluid such as coolant which is compressed by a pump part 5 driven by a motor part 4 passes through a gas passage 10 on the periphery of the motor part 4, and flows into an oil reservoir chamber 7 on the opposite side to the pump part 5. During this time, the motor part 4 is cooled by the fluid. In the oil reservoir chamber 7 which possesses the gas/liquid separating function, the oil (lubricating oil in the pump part 5) is separated and stored from the inflow fluid. Since the pressure in the oil reservoir chamber 7 becomes lower than the pressure in the vicinity of the discharge port of the pump part by the pressure loss of the gas passage 10, the level of the stored oil is increased by that portion. The oil is recirculated to a low pressure part at the center of the pump part 5, passing through the oil passages 2b, 2c, 2d, etc. which are formed inside the wall itself of a housing, by only the pressure difference without using the oil pump.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hermetic compressor suitable for use as a refrigerant compressor in a refrigerating cycle such as an air conditioner or a refrigerator, and more particularly to supplying lubricating oil to a pump portion of the hermetic compressor. It is about.

[0002]

2. Description of the Related Art A conventional example of a hermetic compressor is Japanese Patent Laid-Open No. 1-22.
No. 7896. The hermetic compressor is conventionally often used as a refrigerant compressor in a refrigeration cycle such as a refrigerator or an air conditioner, but both the pump part and the electric motor part that drives the pump are hermetically sealed. It is provided in a common housing, and not only is the overall size smaller than that in which a compressor and an electric motor are provided separately, but depending on the configuration, the motor part may be a refrigerant or pump part. Since it can be cooled by the lubricating oil of, and the drive shaft that connects the pump part and the motor part does not appear outside the common housing, a strict shaft seal device for confining refrigerant and lubricating oil inside the pump part There is no need to provide a common housing, and it is necessary to provide an opening in the common housing and draw it out to the outside. And only the power supply line to the electric motor part, and all of them are immovable, it is easy to seal the opening part of the housing through which they pass, and the sealing device like the case of sealing the drive shaft. It has many excellent advantages that it is easy to maintain without any problems such as leakage of refrigerant or lubricating oil to the outside due to wear of the compressor or deterioration of durability of the compressor.

[0003]

For example, in a horizontal type hermetic compressor, oil (lubricating oil or refrigerating machine oil) for lubricating the sliding portion of the pump portion is mixed with a refrigerant and supplied to the pump portion. In this case, an oil sump chamber is formed around the electric motor part, a gas passage extending from the discharge chamber of the pump part is connected to the oil sump chamber, and the oil is discharged from the refrigerant discharged from the pump part in the oil sump chamber. Is stored separately, and by utilizing the pressure difference between the oil storage chamber and the low pressure part of the pump part whose pressure is lower than that,
It is conceivable to supply the oil to the pump portion only by the pressure difference and suck the oil, without using a pump or the like.

When such means are taken, in order to sufficiently raise the oil level in the oil sump chamber and stably supply the oil to the pump portion, the pressure loss of the refrigerant discharged through the gas passage is relatively large. That is, it is necessary to provide the oil sump chamber at the end position of the motor portion farthest from the pump portion. In that case, the gas passage is formed by a notch shape or the like around the stator of the motor portion for cooling the motor portion by the refrigerant discharged from the pump portion, as shown in the above-mentioned conventional example. can also be, in the case of arranging the oil sump chamber as its is, it must be returned to the pump section of the separated oil in the oil sump chamber located farthest when seen from the pump section.

However, since the housing of the electric motor portion in the conventional hermetic compressor is generally manufactured by drawing a steel sheet into a cylindrical shape by pressing, an oil passage is formed inside the wall of the housing. I can't think of anything to do. Therefore, there is no choice but to suck the oil from the oil sump chamber near the pump part to the pump part, but the oil level in the oil sump chamber near the pump part becomes low for the above-mentioned reason, so that the oil is stably pumped. I can't suck it in.
Therefore, an oil passage is provided inside the shaft so as to communicate with the low pressure portion of the pump portion, and an oil pump is used to suck up the oil from the oil sump chamber to the oil passage inside the shaft. It is necessary to provide some pump means separately for stable supply of Obviously, if a separate pump or the like for oil supply is provided, the structure becomes complicated and the cost increases.

The present invention solves the above problems in the prior art and the idea of improving it, and separately provides pump means for supplying oil to the pump portion of the hermetic compressor. In addition, it is possible to stably supply the oil separated in the oil sump chamber from the fluid such as the compressed refrigerant to the pump portion, and further to provide a simple means by which the motor portion can be cooled by the fluid. The purpose is to do.

[0007]

As a means for solving the above-mentioned problems, the present invention is of a sealed horizontal type which is manufactured as an aluminum casting and which houses both a motor part and a pump part therein. The housing, at least one oil reservoir having a gas-liquid separation function formed in a space at an end of the motor portion opposite to the pump portion, and a compressed fluid discharged from the pump portion. A gas passage that is provided around the motor portion and connects the pump portion and the oil reservoir chamber to each other so as to flow into the oil reservoir chamber, and is separated from the fluid compressed in the oil reservoir chamber. A large part is formed inside the wall of the housing to return the stored oil to the pump part, and the oil reservoir and the pump part And an oil passage that is directly connected to, provide a hermetic compressor and a.

[0008]

The fluid such as the refrigerant compressed in the pump portion driven by the rotation of the motor portion passes through the gas passage provided in the periphery of the motor portion and enters the space at the end opposite to the pump portion. It flows into the formed oil sump chamber. Meanwhile, the motor portion is cooled by the fluid passing through the gas passage. In the oil sump chamber with gas-liquid separation function,
The oil is separated from the inflowing fluid, only the fluid is discharged, and the oil remains. Due to the pressure loss due to the flow path resistance of the gas passage, the pressure in the oil sump chamber becomes lower than the pressure in the vicinity of the discharge port of the pump portion, and the level of the oil accumulated in the oil sump chamber is correspondingly increased. A sufficiently high level of oil will allow the wall of the housing itself to relieve itself due to the pressure differential between the oil sump and the low pressure part of the pump, which has a lower pressure, without the use of means such as an oil supply pump. The oil is stably circulated to the pump portion through the oil passage formed inside the.

[0009]

1 shows a sectional structure of a hermetic compressor as an embodiment of the present invention, and FIG. 2 shows a II-II section thereof. The illustrated embodiment shows an example in which the hermetic compressor of the present invention is used as a refrigerant compressor for compressing a refrigerant in a refrigeration cycle of an air conditioner. In these figures, 1 is a front housing, 2 is a middle housing, and 3 is a rear housing, and these three parts are fastened to each other to form an integral sealed housing. Of these three parts constituting the housing, at least only the middle housing 2 is manufactured by die-cast casting of an aluminum alloy, and holes 2b, 2c, 2d to be oil passages are pre-processed inside a wall having a little thickness. There is.

An electric motor portion 4 which is a drive unit is accommodated inside the middle housing 2, and a pump portion 5 is accommodated inside the rear housing 3. In the illustrated embodiment, a scroll type compressor is used for the pump portion 5, but as the hermetic type compressor of the present invention, a compressor other than the scroll type compressor may be used as the pump portion. it can.

The motor portion 4 is composed of a stator 4a fixed to a cylindrical portion 2a on the inner surface of the middle housing 2 and a rotor 4b rotating therein. A first oil sump chamber 6 is formed on the rear side of the motor portion 4 by utilizing a space inside the cylindrical portion 2a of the middle housing 2, and a second oil sump chamber 7 is formed in an inner space of the front housing 1. Has been formed. First oil sump chamber 6 and second oil sump chamber 7
Are communicated with each other by notches 4c formed at six locations around the stator 4a of the motor portion 4.

Reference numeral 8 is a rear side bearing provided in the middle housing 2, 9 is a front side bearing provided in the front housing 1, and these bearings are shafts integrated with the rotor 4b of the motor portion 4. The front and rear of 11 are pivotally supported. The shaft 11 extends to the pump portion 5 in the rear housing 3 and is formed between the movable scroll member 5a by the drive rotation of the motor portion 4 while revolving the movable scroll member 5a while meshing with the fixed scroll member 5b. The refrigerant is compressed by reducing the crescent-shaped pump space 5c when viewed in the axial direction. The shaft 11 has
A radial hole 11a serving as a gas passage and an axial hole 11b are provided on the right end side, and radial holes 11c and 11e serving as an oil passage and an axial hole 11d are provided in advance on the left end side. .

In the operating state of the hermetic compressor of the illustrated embodiment, the rotor 4b of the motor portion 4 is rotated by the power supply from the power source connected to the connector 14 shown in FIG. Is driven, the refrigerant flowing back from the evaporator of the refrigeration cycle (not shown)
As indicated by a white arrow in FIG. 1, first, the liquid enters the suction chamber 3b through the suction hole 3a provided in the rear housing 3, and is taken into the crescent-shaped pump space 5c from the outer circumference of the two scroll members described above. Is compressed and discharged from the central discharge valve 5d to the rear discharge chamber 13. The compressed refrigerant flows from the rear discharge chamber 13 to the first oil sump chamber 6 through a gas passage (not shown).

The refrigerant discharged from the pump portion 5 contains oil that lubricates the pump portion 5, but most of the oil is in the first oil sump chamber 6 in the stator 4a.
When it collides with, it is separated from the refrigerant and accumulates at the bottom. The refrigerant in the first oil sump chamber 6 is a gas passage consisting of the upper five passages in the six passages formed by the cutout portions 4c provided in the axial direction around the stator 4a. It flows through 10 into the second oil sump chamber 7.

In the second oil sump chamber 7, the oil remaining in the compressed refrigerant is separated, and the refrigerant which contains almost no oil is formed in the shaft 11 in the radial gas passage 11a. And the axial gas passage 11
It is sent out to the condenser of a refrigeration cycle (not shown) through the discharge hole 1b provided in the front end surface 1a of the housing 1 through b. When the refrigerant passes through the gas passages 11a and 11b formed on the shaft 11, the separation action due to the centrifugal force of the slightly remaining oil is additionally generated.

In this way, the oil separated from the refrigerant is collected at the bottoms of the first oil reservoir 6 and the second oil reservoir 7, respectively. In the illustrated embodiment, these oil reservoirs 6 and Since the liquid layer of oil accumulated at each bottom portion of 7 communicates with the lowermost passage 12 of the 6 passages formed by the cutout portion 4c of the stator 4a, the first oil sump chamber 6 The oil collected at the bottom of the oil moves to the second oil sump chamber 7 through the passage 12 for the reason described below. In that sense, the passage 12 will be called an oil passage.

As described above, the refrigerant compressed by the pump portion 5 first flows into the first oil sump chamber 6 and then flows into the second oil sump chamber 7 through the gas passage 10 to both chambers 6, 6. 7 and gas passages 11a, 1 of the shaft 11
Although the oil is separated in 1b and the like and flows out from the discharge hole 1b to the external condenser, since the gas passage 10 has some flow path resistance, the pressure in the second oil sump chamber 7 is reduced to the first by the pressure loss. The pressure becomes lower than that of the oil sump chamber 6, and a pressure difference occurs between the chambers 6 and 7. This is why the oil in the first oil sump chamber 6 flows into the second oil sump chamber 7 through the oil passage 12. As a result, a difference occurs in the oil level between the two chambers 6 and 7, and the oil level in the second oil sump chamber 7 having a low pressure is changed to the first oil sump chamber 6 having a high pressure.
Higher than the oil level of.

Further, since the pressure of the second oil sump chamber 7 is higher than the pressure of the low pressure portion of the pump portion 5 at which the oil is to be sucked, the pressurizing means such as an oil pump can be used. The oil in the second oil reservoir chamber 7 having a higher level is sequentially passed through the oil passages 2b, 2c, 2d formed in the wall surface of the middle housing 2 and the oil passages 11c, 11d, 11e formed in the shaft 11. It becomes possible to lubricate the sliding portion and the like without breaks by flowing into the inside of the pump portion 5 through the. If pump part 5
When it is attempted to supply the oil in the first oil sump chamber 6 to the pump portion 5 because it is close to, it may happen that the oil level becomes low and a sufficient amount of oil cannot be supplied to the pump portion 5. In the illustrated embodiment, since oil is supplied from the second oil sump chamber 7 having a high oil level, there is no such a fear, and the amount of oil required for lubrication is not required by means such as an oil pump.
The pump can be sucked into the pump portion 5 stably only by the pressure difference.

As is well known, the oil supplied to the pump portion 5 has functions such as cooling and assisting the sealing property of the sliding surface, in addition to the lubricating function. The stable operation of these important operations by the oil according to the present invention or the means of the illustrated embodiment also ensures stable operation of the hermetic compressor.

In the case of the illustrated embodiment, the oil passages 2b, 2c, 2d for recirculating the oil from the second oil sump chamber 7 to the pump portion 5 remote from the second oil sump chamber 7 are made of a die-cast aluminum alloy middle housing 2 Since it is formed inside the wall, it is not necessary to provide a special pipe that serves as an oil passage. Aluminum castings are lightweight and very easy to make complex housing shapes.

[0021]

According to the present invention, the oil separated from the fluid such as the compressed refrigerant is accumulated to a high level in the oil storage chamber provided at the farthest position from the pump portion, and the accumulated oil is stored. It is not necessary to provide a special pump means for supplying oil, since the oil can be stably supplied to the pump portion only by the pressure difference through the oil passage provided in the wall of the housing. Also, while the fluid compressed in the pump portion flows through the periphery of the motor portion to the oil reservoir that is farthest from the pump portion, the fluid cools the motor portion, so that a cooling means for the motor portion is provided. No need to provide.

Furthermore, since at least a part of the housing is made of aluminum casting such as die casting, the oil passage can be easily formed in the wall of the housing. Further, even if the housing has a complicated shape, it is easy to manufacture and the weight of the compressor is reduced. In any case, according to the present invention, the structure of the hermetic compressor is simplified and the cost is reduced.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of a hermetic compressor of the present invention.

FIG. 2 is a sectional view taken along the line II-II in FIG.

[Explanation of symbols]

 1 ... Front housing 1b ... Discharge hole 2 ... Middle housing 2b, 2c, 2d ... Oil passage 3 ... Rear housing 3a ... Suction hole 4 ... Motor part 4a ... Stator 4b ... Rotor 4c ... Notch part 5 ... Pump part 6 ... No. DESCRIPTION OF SYMBOLS 1 Oil storage chamber 7 ... 2nd oil storage chamber 10 ... Gas passage 11 ... Shafts 11a, 11b ... Gas passages 11c, 11d, 11e ... Oil passage 12 ... Oil passage 13 ... Rear side discharge chamber

Claims (3)

[Claims] 1. A sealed horizontal housing, which is manufactured as an aluminum casting and accommodates both a motor part and a pump part therein, and a space at an end of the motor part opposite to the pump part. At least one oil sump chamber having a gas-liquid separation function formed in the motor, and a compressor provided in the periphery of the motor part for allowing compressed fluid discharged from the pump part to flow into the oil sump chamber. A gas passage connecting the pump portion and the oil reservoir chamber, and most of the gas passage for returning the oil stored in the oil reservoir chamber separated from the compressed fluid to the pump portion. A hermetic compressor provided with an oil passage formed inside the wall of the housing itself and directly connecting the oil reservoir chamber and the pump portion to each other. 2. A separate oil sump chamber having a gas-liquid separation function is formed in a space of an end portion of the motor part on the same side as the pump part, and the separate oil sump chamber is provided in the at least one The hermetic compressor according to claim 1, which communicates with the oil sump chamber. 3. A hermetic compressor according to claim 1, wherein the compressed fluid is taken out from an end of the motor portion farthest from the pump portion.