JPH08114191A - Hermetic compressor - Google Patents

Abstract

PURPOSE: To prevent heating of intake gas and to improve efficiency by a method wherein when HFC is used as a refrigerant, the position of the opening end on the lower pressure chamber side of a feed oil pipe is also regulated and a proper feed oil amount is ensured, and by arranging a throttle part, freezer oil of an oil reservoir part is cooled by vaporizing a refrigerant contained in freezer oil. CONSTITUTION: A lower pressure chamber 17 partitioned by a vane 12 is kept at a low pressure and by a pressure difference between the part and an oil reservoir part 24 for freezer oil, the freezer oil is fed through a feed oil passage 21 and a throttle part 22. Freezer oil containing a refrigerant is high temperature high pressure at the oil reservoir part 24 but a pressure is reduced at a throttle part 22. In this case, a refrigerant is vaporized, freezer oil is cooled by a gasifying heat, and freezer oil the temperature of which is lowered is fed to a low pressure chamber 17. This constitution mixes high temperature oil in a suction hole, prevents heating of suction gas, feeds the cooled freezer oil, improves efficiency, and feeds the cooled freezer oil to a slide part between the vane 12 and a piston 8 to prevent the occurrence of wear.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hermetic compressor for compressing a refrigerant gas in a refrigeration system or an air conditioner.

[0002]

2. Description of the Related Art A conventional compressor will be described with reference to FIGS. FIG. 4 is a vertical sectional view of the compressor, and FIG. 5 is a horizontal sectional view of the compressor.

In FIG. 5, reference numeral 1 is a closed container in which a refrigerating machine oil 2 is enclosed. Reference numeral 3 is an electric motor, and 4 is a compression mechanism portion, which is driven via a crankshaft 5. The compression mechanism portion 4 is rotatably arranged on the cylinder 6, a eccentric cam 7 provided on the crankshaft 5, and the eccentric cam portion 7, and eccentrically rotates while contacting the eccentric cam 7. Piston 8, an upper end plate 9 and a lower end plate 10 closing both end openings of the cylinder 6, a vane groove 11 provided in the cylinder 6 and extending in a perpendicular direction, and the vane groove 11
It was composed of a vane 12 inserted into and retracted from the inside and having a tip end in contact with the piston 8.

The refrigerating machine oil is supplied from the supply hole 20 by an oil pump 13 (not shown) provided at the lower end of the crankshaft 5 by the rotation of the crankshaft 5 to lubricate the sliding portion. It has become.

The refrigerant is introduced into the compression mechanism section 4 from the suction hole 15 of the cylinder 6 through the gas-liquid separator 14, is discharged once into the closed container 1, and is then discharged from the upper portion of the closed container 1. It is supplied from the pipe 16 to the refrigeration cycle side.

In the sliding portion of such a compression mechanism, it is the vane 12 and the piston 8 that are particularly subject to wear.

The vane 12 reciprocates with the rotation of the crankshaft 5, but the compression chamber is rubbed against the vane groove 11 by the pressure difference between the low pressure chamber 17 and the high pressure chamber 18 of the divided cylinder 6, and the vane 12 is moved. Therefore, the wear of the vane groove 11 becomes a problem.

Further, the tip of the vane 12 is strongly pressed against the outer peripheral portion of the piston 8 by the spring 19 and the pressure on the rear surface of the vane 12, so that the outer peripheral portion of the vane 12 and the tip portion of the piston 8 are worn. . Unlike other sliding parts, for example, the sliding parts of the crankshaft 5 and the upper end plate 9 or the lower end plate 10, this sliding part is not supplied with the refrigeration oil by the oil pump 13 and is refrigerated contained in the sucked refrigerant. Since it was lubricated only with the machine oil and the refrigerating machine oil that bleeds from the end surface of the piston 8, a large supply amount could not be expected, and wear often occurred. In order to solve such a problem, JP-A-57-17
In 3589, an oil injector mechanism 51 as shown in FIG. 6 is proposed. The oil injector 51 is attached to the lower portion of the cylinder 6 so as to communicate with the suction hole 15, and has an oil supply pipe 52 formed of a capillary tube having one end immersed in the refrigerating machine oil 2, a valve 53 opened and closed by a pressure difference, and a coil spring. 54.

By setting the spring force of the coil spring 54 to be larger than the pressure of the closed container 1 during normal operation and smaller than the pressure inside the closed container 1 during abnormal high pressure operation, the abnormal high pressure with a large load is set. During operation, since the piston 8 and the vane 12 in the cylinder 6 are easily worn, the refrigerating machine oil 2 stored in the bottom of the closed container 1 is caused to flow into the suction hole 15 due to the pressure difference, and enters the cylinder 6 together with the refrigerant. Piston 8 and vane 1 in cylinder 6
2 to the surface to prevent abrasion.

Further, during normal operation, high temperature oil is prevented from entering the suction passage and lowering the efficiency.

[0011]

As a refrigerant for such a hermetic compressor, a conventional dichlorofluoromethane (hereinafter referred to as C
FC12) and hydrodifluoromethane (hereinafter referred to as HCFC22) are mainly used. Also,
Regarding the refrigerating machine oil 1 sealed in the closed container 1,
Naphthenic and paraffinic mineral oils that are compatible with C12 and HCFC22 have been used.

Since these refrigerants and refrigerating machine oil circulate directly in the closed container 2, it is necessary that they have abrasion resistance in the compression mechanism section.

Recently, it has been revealed that the release of the above-mentioned refrigerants into the atmosphere leads to the destruction of the ozone layer and seriously affects the human body and biological systems. Therefore, CFC12 and HCFC22
Is gradually restricted from use and it has been decided to abolish it in the future.

Under these circumstances, 1,1,1,2-tetrafluoroethane (hereinafter referred to as HFC) is used as an alternative refrigerant.
134a), pentafluoroethane (hereinafter HF)
C125), hydrofluoromethane (hereinafter H
FC32), mixed refrigerants of these, and the like have been developed.

These HFC134a, HFC125,
HFC32 refrigerant has a low ozone depletion potential, but CFC
12 and mineral oil, which is a refrigerating machine oil used in HCFC22, is hardly compatible. Therefore, HFC134a, 1
When 25, 32, or a mixed refrigerant thereof is used as a refrigerant for a refrigerant compressor, studies have been made on ester-based, ether-based, and fluorine-based oils compatible with these refrigerants as refrigerating machine oil.

However, as the refrigerant, CFC12 or H
Instead of CFC22, HFC134a, HFC125,
In the case of a refrigerant compressor using a polyalkylene glycol-based oil or a polyester-based oil that is compatible with these refrigerants as a refrigerating machine oil using HFC32, gray cast iron used as a sliding material for the above-mentioned compression mechanism unit 4, The wear resistance of special cast iron and stainless steel decreases, and there is a problem in that the refrigerant compressor cannot be operated stably for a long period of time.

This is a conventional refrigerant such as CFC12 or H.
When CFC22 is used, chlorine (C1) atom, which is one of the constituent elements, reacts with Fe atom of the metal substrate to form an iron chloride film having good wear resistance, whereas HFC134a,
One of the causes is that when HFC125, HFC32, etc. are used, a chlorine atom does not exist in these compounds, so that a lubricating film such as iron chloride is not formed and the lubricating action is reduced.

Further, the conventional mineral oil type refrigerating machine oil contains a cyclic compound and has a relatively high oil film forming ability, whereas the refrigerating machine oil compatible with HFC134a, HFC125 and HFC32 is mainly a chain compound. However, it is also difficult to maintain an appropriate oil film thickness under severe sliding conditions, which also reduces wear resistance.

As described above, HFC134a, HFC125, which are new refrigerants replacing CFC12 and HCFC22,
In a refrigerant compressor using HFC32 and a refrigerating machine oil that is compatible with these refrigerants, severe sliding conditions occur not only when the load is high but also when the load is normal, especially wear between the vane 12 and the piston 8. Has become a major issue.

In order to solve such a problem, for example,
When the spring in JP-A-57-173589 is weakened or is removed and oil injection is performed even under normal load, high-temperature oil is injected into the suction hole to heat the suction refrigerant and reduce the efficiency of the compressor. A problem is expected.

The present invention has been invented to solve such a problem, and in particular, an oil film between the partition vane 12 and the piston 8 which has a severe sliding condition even under a normal load using an HFC type refrigerant is used as a compressor. It is an object of the present invention to provide a refrigerant compressor which is formed without lowering the efficiency of (1), has improved wear resistance, and has a long life.

[0022]

SUMMARY OF THE INVENTION The present invention relates to a hermetic compressor in which a compression mechanism portion driven by a drive element having an electric motor is axially arranged in a hermetic container. Is provided with an oil supply passage extending outward in the circumferential direction of the closed container, and the other open end is provided in the low pressure chamber.

Secondly, an oil supply passage extending outward in the circumferential direction of the closed container is provided in the inner peripheral portion of the lower end plate, and the other open end is provided in the low pressure chamber, and moreover, in the middle of the oil supply passage. A narrowed portion is provided.

The present invention is characterized by the above-mentioned constitution, and is particularly applied to a compressor using HFC as a refrigerant and refrigerating machine oil having compatibility with the refrigerant.

[0025]

With this configuration, not only the oil pump is used to supply oil to the sliding portion during operation, but also in the compressor using the HFC system as a refrigerant, the low pressure side of the compression chamber and the oil sump (discharge pressure) even during normal operation. Is supplied to the low pressure chamber through the oil supply passage due to the pressure difference between the oil pressure and the oil pressure, and an appropriate oil film is formed between the piston and the vane.

The refrigerating machine oil in the oil sump portion has the refrigerant dissolved therein, and the refrigerating machine oil passing through the oil supply passage is decompressed by the throttle portion. At this time, the refrigerant that has been melted evaporates and cools the refrigerating machine oil, so that the temperature of the refrigerating machine oil decreases, and after cooling, the refrigerant enters promptly into the compression chamber, so that the suctioned refrigerant is not heated.

The oil supply amount increases as the pressure difference increases, and when the load is high, the oil supply amount can be increased and wear can be prevented.

Further, by adjusting the position of the opening of the low pressure chamber, the opening timing per one rotation can be changed and the amount of oil supply can be adjusted.

With the above structure, the reliability of the sliding portion, particularly the piston and the vane is improved without lowering the efficiency of the compressor.

[0030]

1 is a vertical sectional view of a first invention of a compressor of the present invention, FIG. 2 is a vertical sectional view of a second invention of a compressor of the present invention, and FIG. 3 is a horizontal sectional view thereof. Is.

An electric motor 3 and a compression mechanism portion 4 driven by the electric motor 3 via a crankshaft 5 are arranged in the closed container 1, and the compression mechanism portion 4 is provided with a cylindrical cylinder 6 and the crankshaft 5. The eccentric cam 7 provided on the
A rotatably arranged piston 8, which eccentrically rotates while being in contact with the eccentric cam 7, an upper end plate 9 and a lower end plate 10 closing both end openings of the cylinder 6, and a diametrical direction provided in the cylinder 8. The vane groove 11 extends, and the vane 12 is inserted into the vane groove 11 so as to be retractable and has a tip contacting the piston 8.

Refrigerating machine oil 2 is enclosed in the bottom of the closed container 1. This refrigerating machine oil is a conventional refrigerant CFC12, H
In the case of CFC22, naphthene-based or paraffin-based mineral oil or alkylbenzene-based oil has been generally used. In the case of HFC type refrigerant, ether type and ester type oils having compatibility with the refrigerant are enclosed.

The crankshaft 5 is provided with an oil pump 13 (not shown), and while rotating, from the oil supply hole 20,
The refrigerator oil 2 is supplied to the sliding portion.

An oil supply passage 21 extending outward in the circumferential direction of the closed container is provided on the inner peripheral portion of the lower end plate 10, and the other open end is provided in the low pressure chamber 17 of the compression chamber 19.

A throttle portion 22 is provided in the oil supply passage 21. The crankshaft 5 is driven by the electric motor 3, and the planetary motion of the piston 8 draws in a refrigerant gas such as HFC, compresses it, and then discharges it into the closed container 1. At this time, the vane 12 partitioning the compression chamber slides while being pressed against the outer periphery of the viston 8 by the pressure applied to the spring 23 and the back of the vane 12. The lubrication of this sliding point is mainly due to the refrigerating machine oil mixed from the intake gas. Refrigerant oil is slightly contained in the sucked refrigerant gas, but it is not sufficient, and lubricity cannot be expected only with this amount. Especially HFC
Is not enough.

The low-pressure chamber 17 partitioned by the vanes 12 is, of course, at a low pressure, and due to the pressure difference between this portion and the oil sump 24 of the refrigerating machine oil, the refrigerating machine oil is passed through the oil supply passage 21 and the throttle portion 22. Supplied.

Refrigerating machine oil containing this refrigerant is stored in the oil reservoir 24.
In the above, the temperature is high temperature and high pressure, but the pressure is reduced by the throttle portion 22. At this time, the refrigerant evaporates, the refrigerating machine oil is cooled by the heat of vaporization, and the refrigerating machine oil whose temperature has dropped is supplied to the low pressure chamber 17. In the case of the conventional oil injection mechanism,
Since the capillary tube is arranged in the oil sump, decompression is performed by the capillary tube immersed in the oil sump. For this reason, even if the oil in the thin tubes is cooled, it immediately receives heat from the surrounding oil, and almost hot oil mixes into the suction holes, which causes heating of the suction gas, leading to a reduction in compressor efficiency. It was However, the configuration of the present invention prevents heat from being received from the surroundings and supplies cooled refrigerating machine oil, which does not lead to a decrease in efficiency.

The refrigerating machine oil 1 supplied into the compression chamber enters the sliding portion between the piston 8 and the vane 12 and forms an oil film to prevent abrasion.

The refrigerating machine oil mixed in the compression chamber is discharged together with the refrigerant from the compression mechanism section 4, is sifted off while passing through the notch of the electric motor 3, and most of it returns to the oil sump section 24. In this way, by suppressing the refrigerating machine oil circulating in the refrigerating cycle, it is possible to prevent the heat exchanging of the heat exchanger from being hindered by the refrigerating machine oil and improve the efficiency of the refrigerating cycle.

Further, the larger the pressure difference, the more the refrigerating machine oil is mixed. This means that a larger amount of lubricating oil is supplied when the pressure difference that is severe for the sliding portion is larger, and reliability is improved. Above, especially vane 12
The case where a compressed gas is an HFC-based refrigerant in which the sliding condition between the piston 8 and the piston 8 is severe has been described.
2. Similar effects can be expected when using the HCFC22.

[0041]

As described above, according to the present invention, the hermetic container 1 is provided with the electric motor 3 and the compression mechanism portion 4 driven by the electric motor 3 through the crankshaft 5, and the compression mechanism portion 4 is provided.
A cylindrical cylinder 6, an eccentric cam 7 provided on the crankshaft 5, a piston 8 rotatably arranged on the cam portion 7, and eccentrically rotating while being in contact with the eccentric cam 7, An upper end plate 9 and a lower end plate 10 closing both end openings of the cylinder 6, a diametrically extending vane groove 11 provided in the cylinder 6, and a vane groove 11 which is removably inserted into the vane groove 11 and whose tip is It is composed of a vane 12 that contacts the piston 8.

An oil supply passage 21 extending outward in the circumferential direction of the closed container is provided on the inner periphery of the lower end plate 10, and the other open end is provided in the low pressure chamber 17 of the compression chamber. Further, it is a hermetic compressor in which the throttle portion 22 is provided in the oil supply passage 21.

With the above structure, even when HFC is used as the refrigerant, by adjusting the position of the opening end of the oil supply passage 21 on the low pressure chamber 17 side, an appropriate amount of oil supply can be secured, and further, the throttle portion 22. Is provided, the refrigerating machine oil 2 in the oil sump 24 is cooled by evaporating the refrigerant contained in the refrigerating machine oil 2. As a result, the cooled refrigerating machine oil can be supplied to the sliding portion between the vane 12 and the piston 8.

Further, as the load is higher, a larger amount of refrigerating machine oil can be supplied, so that higher reliability can be obtained.
Further, since the cooled refrigerating machine oil is supplied, the intake gas is not heated, and the refrigerating machine oil circulating in the refrigeration cycle can be suppressed to be small, so that it is possible to realize a highly efficient device. Is.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a hermetic compressor of the present invention.

FIG. 2 is a vertical sectional view of the hermetic compressor of the present invention.

FIG. 3 is a transverse sectional view of the hermetic compressor of the present invention.

FIG. 4 is a vertical sectional view of a hermetic compressor of a conventional example.

FIG. 5 is a cross-sectional view of a hermetic compressor of a conventional example.

FIG. 6 is a vertical sectional view of a hermetic compressor of a conventional example.

[Explanation of symbols]

 1 Airtight Container 2 Refrigerator Oil 3 Electric Motor 4 Compression Mechanism 5 Crankshaft 6 Cylinder 7 Eccentric Cam 8 Piston 9 Top Plate 10 Bottom Plate 11 Vane Groove 12 Vane 13 Oil Pump 14 Gas-Liquid Separator 15 Suction Port 16 Discharge Pipe 17 Low Pressure Chamber 18 High-pressure chamber 19 Spring 20 Oil supply hole 21 Oil supply passage 22 Throttling part 23 Spring 24 Oil sump 51 Oil injector 52 Oil supply pipe 53 Valve 54 Coil spring

Claims (3)

[Claims] An electric motor and a compression mechanism portion driven by the electric motor via a crankshaft are provided in a closed container, and the compression mechanism portion has a cylindrical cylinder and an eccentricity provided on the crankshaft. A cam, a piston rotatably arranged on the eccentric cam and rotating eccentrically while contacting the eccentric cam, an upper end plate and a lower end plate closing both end openings of the cylinder, and a diametrical direction provided on the cylinder. A vane groove extending into the vane groove, and a vane that is inserted into and retractable from the vane groove and has a tip that contacts the piston, and further has an oil supply hole at a position corresponding to the lower end plate of the crankshaft, A hermetic compressor characterized in that an oil supply passage extending outward is provided in the inner peripheral portion of the lower end plate, and the other open end is provided on the suction hole side of the compression chamber. 2. HFC (hydrofluorocarbon) containing no chlorine atom is used alone or as a refrigerant, and the refrigerating machine oil is filled with a refrigerating machine oil compatible with the refrigerant in a hermetically sealed container for refrigeration / air conditioning. In a hermetic compressor that constitutes a system, an electric motor and a compression mechanism section driven by the electric motor via a crankshaft are arranged in a hermetic container, and the compression mechanism section is provided in a cylindrical cylinder and the crankshaft. An eccentric cam, a piston rotatably disposed on the eccentric cam portion, which eccentrically rotates while contacting the eccentric cam, an upper end plate and a lower end plate closing both end openings of the cylinder, and the cylinder. And a vane groove extending in the diametrical direction, and the vane groove is inserted into the vane groove so that the vane groove can retract.
The tip of the vane is in contact with the piston, and an oil supply hole is provided at a position corresponding to the lower end plate of the crankshaft, and the inner peripheral portion of the lower end plate extends outward in the circumferential direction of the closed container. A hermetic compressor characterized in that an oil supply passage for discharging is provided and the other open end is provided on the suction hole side of the compression chamber. 3. The hermetic compressor according to claim 1, wherein a throttle portion is provided in the oil supply passage on the suction hole side.