JP3413916B2 - Hermetic rotary compressor - Google Patents

Description

Detailed Description of the Invention

[0001]

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

[0002]

2. Description of the Related Art FIGS. 7 and 8 show a conventional hermetic rotary compressor. FIG. 7 is a vertical sectional view, and FIG. 8 is a horizontal sectional view.

In FIG. 7, reference numeral 1 denotes a hermetically sealed container in which an electric motor 2 composed of a stator 2-1 and a rotor 2-2 is installed.

A compression mechanism 3 is arranged below the electric motor 2, and the compression mechanism 3 is driven by the electric motor 2.

As a result, the refrigerant introduced from the suction hole 5 via the suction pipe 4 via the accumulator (not shown) is compressed and once discharged from the discharge hole 6 into the closed container 1, and then provided on the upper part of the closed container 1. Refrigerant is supplied to the refrigeration cycle side from the discharged discharge pipe 7.

The compression mechanism 3 is constructed as follows. FIG. 8 is an enlarged view. A shaft 8 driven by the electric motor 2 is axially supported by a main bearing 9 and penetrates through the cylinder 10, and a lower end portion thereof is axially supported by a sub bearing 11.
Inside the cylinder 10 of the shaft 8, the crank portion 12
(Eccentric part) and this crank part and cylinder 10
A roller 13 is fitted between the roller and the roller 13, and the roller 13 makes a planetary motion by the rotation of the shaft 8.

Further, the vane 14 penetrates through the cylinder 10.
The one end side of the vane 14 contacts the outer circumference of the roller 13 by the urging force of the spring 15 to divide the inside of the cylinder 10 into a suction chamber 16 and a compression chamber 17. The roller 13
The vane 14 reciprocates according to the planetary motion of the.

Refrigerant gas is sucked from the suction hole 5 in accordance with the planetary movement of the roller 13 accompanying the rotation of the shaft 8, is compressed and is discharged from the discharge notch 19, but is sealed to smooth the operation of this sliding portion. Refrigerating machine oil is contained in the container 1. This refrigerating machine oil is sucked up by the rotation of the shaft 8 by the pump 21 provided at the lower end of the shaft 8 to lubricate each sliding portion.

It is the vanes 14 that wear is particularly problematic in the sliding portion of such a compression mechanism.

The vane 14 reciprocates along with the rotation of the shaft 8. At this time, the vane 14 and the cylinder through hole 18 are rubbed against the inner surface of the through hole 18 of the cylinder 10 due to the pressure difference between the two chambers in the divided cylinder 10. Is a problem. Further, since the end of the vane 14 is pressed against the roller 13 by the pressure of the spring 15 and the back surface of the vane, the tip of the vane and the outer peripheral portion of the roller 13 also slide. Unlike the other sliding portions (such as the shaft bearing portion), this sliding portion is not directly supplied with oil from the oil pump 21. The oil supply to this part is conventionally lubricated by the oil contained in the suctioned refrigerant and the oil oozing out from the roller end, and it is not possible to expect a large amount of supply, and the temperature of this sliding part is reduced by the compression of the refrigerant. It became a high temperature and became the most severe sliding part, and was often worn. In order to solve such a problem, JP-A-4-203286 proposes an oil injector mechanism as shown in FIG. In the refrigeration cycle, the liquid refrigerant is branched from the pipe line 24 guided from the condenser 22 to the expansion valve 23, and the liquid injection bypass line 25 for injecting the oil and the liquid refrigerant into the suction chamber 16 in the cylinder is provided. An oil tank 26 is provided on the way. The oil in the oil tank 26 is caused to flow into the suction chamber 16 in the cylinder due to the pressure difference, and the oil is transferred to the roller 13 in the cylinder.
And to the surface of the vane 14 to prevent abrasion. Also,
When only oil is supplied, high temperature oil penetrates into the cylinder to reduce efficiency, so that the liquid refrigerant is mixed to prevent heating in the cylinder.

[0011]

As a refrigerant for such a hermetic refrigerating compressor, there are conventionally used dichlorodifluoromethane (hereinafter referred to as Freon 12 (CFC12)) and hydrochlorodifluoromethane (hereinafter referred to as Freon 22 (HCFC22)). Primarily used), and as the refrigerating machine oil sealed in the compression mechanism 5, naphthene-based or paraffin-based mineral oils that are soluble in CFC12 and HCFC22 are used.

Since these refrigerant and refrigerating machine oil circulate directly in the closed container 1, the compression mechanism 5 must have wear resistance.

By the way, recently, it has become clear that the release of CFCs from the above-mentioned refrigerants leads to the destruction of the ozone layer and seriously affects the human body and the ecosystem, so CFCs 12, CFCs 22 and the like should be used in stages. It has been decided that it will be reduced and will be abolished in the future.

Under such circumstances, 1,1,1,2-tetrafluorotaene (hereinafter referred to as Freon 134a (HFC134a)) and 1,1 difluoroethane (hereinafter referred to as 152a (HFC152a)) are used as alternative refrigerants. ),
Hydrofluoromethane (hereinafter CFC 32 (HFC3
2)), or a mixed refrigerant of these, and the like have been developed.

By the way, these Freon 134a and Freon 1
The refrigerants 52a and Freon 32 have a low ozone depletion potential, but hardly dissolve in mineral oil, which is the refrigerating machine oil used in the use of Freon 12 and Freon 22. Therefore, when CFCs 134a, CFCs 152a, CFCs 32, or mixed refrigerants thereof are used as refrigerants for refrigerant compressors, ether-based oils, ester-based oils, fluorine-containing oils that are compatible with these refrigerants as refrigerating machine oil. Attempts have been made to use system oils.

However, instead of the Freon 12 or Freon 22 as the refrigerant, HFC134a, HFC15
2a, or a refrigerant compressor using HFC32 and compatible with these refrigerants as a refrigerating machine oil, for example, using a polyalkylene glycol-based oil or polyester-based oil,
F used as a sliding member of the compression mechanism 3 described above
The wear resistance of C25, special cast iron, sintered alloys, stainless steel, etc. is lowered, and there is a problem that the refrigerant compressor cannot be operated stably for a long period of time.

This is because when Freon 12 or Freon 22 is used as the conventional refrigerant, chlorine (C) in the Freon is used.
l) Atoms react with Fe atoms of the metal base material to form an iron chloride film with good wear resistance, whereas when CFCs 134a, CFCs 152a or CFCs 32 are used, these compounds are included in these compounds. One of the causes is that a lubricating film such as an iron chloride film is not formed due to the absence of Cl atoms 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 the Freon 134a, Freon 152a and Freon 32 is a chain compound. Is the main factor, and the fact that an appropriate oil film thickness cannot be maintained under severe sliding conditions is also a factor that promotes a reduction in wear resistance.

In this way, new refrigerants such as Freon 134a (HFC134a) and Freon 152a (H) which replace Freon 12 (CFC12) and Freon 22 (HCFC22).
FC152a) or Freon 32 (HFC32) and a refrigerant compressor that uses a refrigerating machine oil compatible with these refrigerants have severe sliding conditions not only when the load is high but also when the load is normal. The wear between rollers has become a major issue.

An example of solving this problem by supplying a larger amount of oil between the vane and the roller is Japanese Patent Laid-Open No. 4-20.
In the case of the oil injector mechanism in 3286, there is a problem that the refrigeration cycle becomes complicated and expensive.

However, if the oil sump and the suction chamber are simply connected, a high temperature oil is injected into the suction chamber, and the suction refrigerant is overheated, resulting in a problem of reducing the efficiency of the compressor.

The present invention has been made to solve the above problems. In particular, it is possible to improve the efficiency by using a simple structure of a compressor, by using a vane and a roller oil film that have a harsh sliding condition using an HFC type refrigerant. An object of the present invention is to provide a refrigerant compressor which is formed without lowering it, has improved wear resistance, and has a long life.

[0023]

SUMMARY OF THE INVENTION The present invention is directed to a rolling piston type rotary compressor having an axially disposed compressor element driven by a drive element having an electric motor in a closed container, in a bottom portion of the closed container. The oil reservoir and the suction chamber in the cylinder are connected by an oil supply path, and the oil supply path is provided in the vicinity of the suction chamber in the cylinder and a throttle portion is provided. The holder is attached to a sub-bearing, and is particularly applied to a compressor using HFC as a refrigerant and refrigerating machine oil compatible with the refrigerant.

[0024]

With this structure, not only the oil pump supplies oil to the sliding portion during operation, but also the suction chamber and the oil reservoir (discharge pressure) in the cylinder during normal operation of the compressor using the HFC system as a refrigerant. By the pressure difference between and, and the throttle portion, an appropriate amount of oil corresponding to the load is mixed into the suction refrigerant, and an appropriate oil film is formed between the vane and the roller by this oil.

The refrigerant melts into the oil in the oil sump, and the oil that has passed through the oil supply path is decompressed by the throttle in the cylinder immediately before the suction chamber. At this time, the melted refrigerant evaporates and cools the oil, so that the temperature of the oil drops and the cooled refrigerant quickly enters the suction chamber, so that the suctioned refrigerant is not overheated. As a result, the reliability is improved with a simple structure without lowering the efficiency, especially between the sliding portion, particularly the vane and the roller.

Further, the opening of the oil supply path is opened and closed by rollers so that an appropriate amount of oil is injected.

[0027]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A description will be given with reference to FIGS. 1, 2 and 3.

An electric motor portion 2 and a compression mechanism portion 3 are arranged inside the container 1, and a shaft 8 directly connected to the electric motor portion is supported by a main bearing 9 and an auxiliary bearing 11. A roller 13 is arranged in the cylinder 10 and penetrates the shaft 8 and the eccentric portion to perform a planetary motion.

The vane 14 inserted into the through-hole 18 of the cylinder 10 has the spring 15 and the cylinder 10a pressed against the roller 13 by the back pressure (discharging pressure).
6 and compression chamber 17.

Refrigerating machine oil is enclosed in the bottom of the closed container 1 to a level at which the entire cylinder can be used during normal operation. As the refrigerating machine oil, naphthene-based or paraffin-based mineral oil and alkylbenzene-based synthetic oil are generally used in the conventional refrigerants R12 and R22, but in the case of HFC-based refrigerant, ether-based ester oil compatible with the refrigerant is sealed. To be done. Due to their compatibility under normal operating conditions, a considerable amount of refrigerant is dissolved in the refrigerating machine oil at the bottom of the closed container.

The oil sump 20 at the bottom of the closed container and the suction chamber 16 in the cylinder are connected by an oil supply path.

This oil supply path has a hole 32a formed at a right angle to the suction chamber 16 in the cylinder, a holder 27a having a throttle portion 34 and a screw portion, and an oil supply pipe attached to the auxiliary bearing 11 with the holder 27a held therein. 28a.

The oil supply pipe 28a is opened near the bottom of the closed container, and a filter 29a is attached to the tip of the oil supply pipe 28a for the purpose of protecting the clogging of the throttle portion 34. FIG. 2 shows details of the mounting portion of the holder 27a having the throttle portion 34.

A thin tube 30 is press-fitted into the holder 27a, and this thin tube 30 has a hole having a diameter of 1 mm or less and has a throttling action. Instead of the thin tube 30, it is possible to directly make a thin hole in the holder 27a.

The auxiliary bearing 11 has a holder holding hole 31.
a is provided. A screw is cut at the end of the holding hole 31a, and the holder 27a is fixed to the auxiliary bearing 11 by this screw portion, whereby the tip of the insertion portion of the holder 27a is crimped to the stepped portion 33a, and a high and low pressure seal is provided. To do. This structure makes it easy to install. As a result, the throttle portion 34 can be arranged in the cylinder near the suction chamber 16.

For the oil supply pipe 28a, the holder 27a is attached to the auxiliary bearing 1.
When it is attached to No. 1, the holder opening may be omitted because it is located considerably below.

Further, in the examples of FIGS. 5, 6 and 7, a hole 32b and a holding hole 31b of the holder 27b are provided in the side surface of the cylinder 10b, and a screw is cut at the end of the holding hole 31b. The holder 27b is fixed to the side surface of the cylinder 10 with this screw portion, and the tip of the insertion portion of the holder 27b is crimped to the stepped portion 33b. Further, an oil supply pipe 28b is attached to the holder 27b.

The oil supply pipe 28b is an L-shaped pipe, is opened in the vicinity of the bottom of the closed container, and has a filter 29b attached to the tip thereof in order to protect the clogging of the throttle portion 34.

The details of the mounting portion of the holder 27b having the throttle portion 34 are as described above. The operation of this configuration will be described with reference to FIGS. 1, 2, and 3. The shaft 8 is driven by the electric motor 2, and the planetary motion of the roller 8 causes the refrigerant gas such as HFC to be sucked into the suction chamber 16 from the suction pipe 6 through the suction hole 5, and the pressure in the compression chamber 17 rises to cause the discharge notch. It is discharged from the discharge hole 6 into the closed container 1 via 19.

At this time, the vane 14 for partitioning the suction chamber 16 and the compression chamber 17 is pressed against the outer periphery of the roller 13 by the pressure applied to the spring 15 and the back of the vane, and moves while sliding at the contact point. The lubrication of this sliding point is mainly lubricated by the oil mixed in the intake gas. Since the amount of oil contained in the refrigerant gas circulating in the refrigeration cycle is very small, this amount alone is not sufficient for HFCs in which the slidability of the refrigerant cannot be particularly expected.

Needless to say, the suction chamber 16 in the cylinder has a low pressure. Due to the pressure difference between this portion and the high pressure portion of the oil sump portion 20, dust is removed by the filter 29 and oil is supplied in the order of the oil supply pipe 28 and the throttle portion 34. It is supplied to the suction chamber 16 in the cylinder.
The oil in the oil sump is selected in consideration of the compatibility with the refrigerant used, and therefore contains a considerable amount of the refrigerant. The oil containing the refrigerant has high temperature and high pressure in the oil sump, but is depressurized in the throttle. At the time of this pressure reduction, the refrigerant evaporates, the heat of vaporization cools the oil, and the cooled oil is mixed in the suction chamber.

In the case of the conventional oil injection mechanism, liquid refrigerant injection is mixed in order to solve the problem that high temperature oil is injected into the suction chamber 16 to overheat the suction refrigerant and reduce the efficiency of the compressor. However, there is a problem that the refrigeration cycle becomes complicated and expensive.

However, according to the present invention, since the throttle portion is arranged in the vicinity of the suction chamber 16, the structure of the compressor is simple, and the oil whose temperature has dropped is not received by the heat from the surroundings. It is not mixed in 16 and the efficiency is not lowered.

The opening 35 of the hole 32 to the suction chamber 16 is blocked or opened by the thick portion of the roller depending on the rotation angle of the shaft 8 by the rotation of the roller 13.
By opening and closing the opening 35 of the hole 32 to the suction chamber 16,
The amount of oil supplied to the suction chamber 16 in the cylinder is adjusted. Further, by setting the opening position of the hole 32, an appropriate amount of oil can be supplied to the suction chamber 16 in the cylinder.

The oil mixed in the suction chamber 16 is the roller 1
3 and the vane 14 enter the sliding portion to form an oil film and prevent wear. The oil mixed in the suction chamber 16 and lubricating the sliding portion is discharged from the discharge hole 6 together with the discharge gas. The oil discharged from the discharge hole 6 is removed while passing through the cutout portion of the electric motor 2, and most of it returns to the oil sump 20. Therefore, the amount of oil that exits the discharge pipe 9 and circulates in the refrigeration cycle can be reduced. When the amount of oil circulating in the refrigeration cycle is reduced, the heat exchange inhibition of the heat exchanger by the oil does not occur, so the efficiency of the refrigeration cycle is further improved.

Further, since the oil mixed in the suction chamber 16 passes through the throttle portion, the larger the differential pressure, the larger the amount of oil 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. Improves reliability. A larger amount of lubricating oil will be supplied over time. Improves reliability.

Although the case where the compressed gas is the HFC type refrigerant in which the sliding condition between the vane and the roller is severe has been described above, the same effect can be expected in the conventional HCFC22.

[0048]

As is apparent from the above embodiments, the present invention is a hermetic rotary compressor, in which a bottom oil sump in a hermetic container and a suction chamber in a cylinder are connected by an oil supply path. A throttle portion is provided in the oil supply passage in the vicinity of the suction chamber in the cylinder. Even when the sliding condition using HFC as a refrigerant is severe, the oil in the oil sump is immediately before the suction chamber in the cylinder. Since the refrigerant contained in the oil evaporates through the throttling part, the cooled oil can be supplied to the sliding portion between the vane and the roller, and a large amount can be supplied when the load is high, so that the reliability is high. . Further, since the supplied oil is cooled, the intake gas is not overheated, and the amount of oil circulated in the refrigeration cycle can be suppressed to be small, so that an apparatus with high efficiency can be realized.

Further, by opening and closing the opening of the oil supply path by the roller, there are various advantages such that a proper amount of oil can be injected with a simple structure.

[Brief description of drawings]

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

FIG. 2 is an enlarged sectional view of an essential part of the hermetic compressor according to the present invention.

FIG. 3 is a cross-sectional view of the hermetic compressor according to the present invention.

FIG. 4 is a vertical sectional view of another embodiment of the hermetic compressor according to the present invention.

FIG. 5 is an enlarged sectional view of an essential part of another embodiment of the hermetic compressor according to the present invention.

FIG. 6 is a cross-sectional view of another embodiment of the hermetic compressor according to the present invention.

FIG. 7 is a vertical sectional view of a conventional hermetic compressor.

FIG. 8 is a transverse sectional view of a conventional hermetic compressor.

FIG. 9 is a refrigeration cycle diagram of a conventional oil injector mechanism.

[Explanation of symbols]

1 closed container 2 electric motor 3 compression elements 5 suction holes 6 discharge holes 8 shafts 9 Main bearing 10 cylinders 11 Secondary bearing 13 Roller 14 vanes 16 Inhalation chamber 17 Compression chamber 18 Cylinder through hole 20 oil reservoir 34 Throttle 35 opening

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shigeru Muramatsu 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (56) Reference JP-A-6-323276 (JP, A) (58) Field (Int.Cl. ⁷ , DB name) F04C 29/02 F04C 18/356

Claims (5)

(57) [Claims] 1. An electric motor and a compressor element driven by the electric motor are axially arranged in a closed container having an oil sump portion at the bottom , and the compressor element is fixed to a cylinder and both ends of the cylinder. a main bearing and an auxiliary bearing, the shaft having a crank is rotatably accommodated in the main bearing and the sub-bearing, a roller eccentrically rotating within said cylinder fitted to the crank of the shaft, in the radial direction to said cylinder Setting
A vane for dividing the inside of the cylinder to the compression chamber and the suction chamber by the roller and the contact with reciprocating digit through-hole, a discharge hole for discharging the compressed refrigerant into the closed vessel
And an oil supply path connecting the oil reservoir and the suction chamber
The hermetically sealed rotary compressor, wherein
And the flat surface formed in the direction perpendicular to the axis
And a holder having a thin hole formed through in the axial direction
The holder is a flat surface formed in a direction perpendicular to the axis.
Auxiliary bearing or cylinder so that the part is in close contact with the mating member
A hermetic rotary compressor characterized by being screwed into . 2. A refrigerant as HFC, according holes 1, wherein the using the refrigerating machine oil having a refrigerant compatibility
The sealed-type rotary compressor. 3. The suction chamber side opening of the oil supply passage is eccentrically rotated.
Characterized by intermittently opening the roller
The hermetic rotary compressor according to claim 1 or 2 . 4. A holder is screwed into the auxiliary bearing,請<br/> Motomeko 3 sealed-type rotary compressor, wherein the opening and closing of the opening of the oil supply path by a roller end face. 5. holder is screwed to the cylinder, sealed-type rotary compressor <br/> claim 3, wherein the opening and closing of the opening of the oil supply path roller side.