JP7235577B2 - rotary compressor - Google Patents

Description

The present invention relates to rotary compressors.

2. Description of the Related Art Conventionally, a hermetic electric rotary compressor has a housing, a rotating shaft extending vertically in the housing and rotated by an electric motor, and a cylinder supported by the rotating shaft, as disclosed in Patent Document 1, for example. A rotary compressor, and an upper bearing and a lower bearing that are rotatably supported by a rotating shaft and fixed above and below a cylinder are known.

JP 2015-17574 A

However, conventional rotary compressors have the following problems.
That is, conventionally, a metal material is generally used because the rotary compression part requires strength to withstand the reaction force during gas compression. On the other hand, rotary compressors are required to be made smaller and lighter to reduce noise. However, since it is difficult to reduce the weight of the rotary compression portion formed of a metal material, there is room for improvement in this respect.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a rotary compressor capable of reducing the weight of the entire rotary compressor.

In order to achieve the above object, a rotary compressor according to one aspect of the present invention includes a housing, a rotating shaft extending vertically in the housing, a cylinder having a compression chamber inside which the rotating shaft is inserted, An upper bearing and a lower bearing that rotatably support the rotating shaft and are fixed above and below the cylinder are provided. and the lower bearing covers the compression chamber from below, at least a part of at least one of the upper bearing and the lower bearing is formed of a resin material, and the rotation in the upper bearing and the lower bearing An inner surface facing the shaft is made of a metal material, and all inner surfaces of the upper bearing and the lower bearing facing the compression chamber are made of a metal material.

According to the rotary compressor according to the above aspect, weight reduction can be achieved by forming at least a part of the cylinder, which is a heavy part of the rotary compressor, from a resin material, and the weight of the entire rotary compressor can be reduced.
Further, according to such a configuration, at least one of the upper bearing fixed to the cylinder and the lower bearing is partially made of a resin material so that at least one of the bearings is made of a resin material to reduce weight. Furthermore, the weight of the entire rotary compressor can be reduced.
Further, according to such a configuration, it is possible to improve the wear resistance of the sliding surfaces, which are the inner surfaces of the upper and lower bearings facing the rotating shaft, against the rotating shaft. In addition, it is possible to improve the wear resistance against the compressed gas on the inner surfaces of the upper and lower bearings facing the compression chambers and the parts inside the compression chambers.

Further, in the above rotary compressor, a seal is provided at a position where a portion of the cylinder made of the resin material and a portion made of the resin material of at least one of the upper bearing and the lower bearing contact each other. may be provided.

According to such a configuration, it is possible to provide the contact portion of the resin material, which is inferior in dimensional accuracy to the metal material, with sealing performance equivalent to that of the contact of the metal material.

In the above rotary compressor, the inner surface of the cylinder forming the compression chamber may be made of a metal material.

According to such a configuration, it is possible to improve the wear resistance of the compressed gas on the inner surface of the cylinder and the parts inside the compression chamber.

According to the rotary compressor of the present invention, the weight of the entire rotary compressor can be reduced.

BRIEF DESCRIPTION OF THE DRAWINGS It is the longitudinal cross-sectional view which showed the structure of the rotary compressor by 1st embodiment of this invention. FIG. 2 is a vertical cross-sectional view showing portions of a cylinder, an upper bearing, and a lower bearing made of a resin material of the rotary compressor according to the first embodiment of the present invention; FIG. 2 is a cross-sectional view taken along line AA shown in FIG. 1 and is a horizontal cross-sectional view of a plane perpendicular to the central axis of the compressor in the cylinder; FIG. 7 is a horizontal cross-sectional view of a plane perpendicular to the central axis of the compressor in the cylinder of the rotary compressor according to the second embodiment of the present invention;

[First embodiment]
A rotary compressor according to an embodiment of the present invention will be described below with reference to the drawings. This embodiment shows one aspect of the present invention, does not limit the present invention, and can be arbitrarily changed within the scope of the technical idea of the present invention.

As shown in FIG. 1, the rotary compressor according to the present embodiment (hereinafter simply referred to as compressor 1) is an example of a closed-type electric rotary compressor used in air conditioners, refrigeration equipment, and the like. It has a main body 10 , a suction pipe 11 and an accumulator 12 . As refrigerants compressed by the compressor 1, HFO (hydrofluoroolefin) refrigerants such as R32 and R454C, and natural refrigerants such as CO ₂ , propane, and helium are used.

The compressor body 10 has a housing 2 , a rotating shaft 3 , an upper bearing 4A, a lower bearing 4B, an electric motor 5 and a rotary compression section 6 . A disk-shaped cylinder 60 is provided in the housing 2 in the rotary compression section 6 .
Here, the central axis of the housing 2 and the rotating shaft 3 are arranged on a common axis extending in the vertical direction (vertical direction). The rotating shaft 3 is arranged so that its extending direction is the vertical direction, and is housed in the housing 2 so as to be rotatable around the rotation axis O. As shown in FIG.

The housing 2 is a closed type and extends vertically. The housing 2 has a cylindrical body portion 21 and an upper lid portion 22 and a lower lid portion 23 that close upper and lower openings of the body portion 21 . The housing 2 is formed with an opening 24 at a position facing the outer peripheral surface of the cylinder 60 in the lower portion of the side wall. A suction port 25 is formed in the cylinder 60 at a position facing the opening 24 and communicates with a predetermined position in the cylinder.

An oil reservoir is formed at the bottom of the housing 2 by collecting refrigerator oil. The liquid surface of the oil pool is located above the rotary compression portion 6 when the oil is initially filled. Thereby, the rotary compression part 6 is driven in the oil pool. Synthetic hydrocarbon oil (benzene oil), ether/ester oil, and mineral oil used as refrigerating machine oil can be used.

The upper lid portion 22 is provided with a discharge pipe 13 that penetrates in the thickness direction and has a lower portion disposed inside the housing 2 and an upper portion disposed outside the housing 2 . The discharge pipe 13 discharges the compressed refrigerant containing oil to the outside of the housing 2 .

An accumulator 12 is provided outside the housing 2 to separate the refrigerant from gas and liquid prior to being supplied to the compressor main body 10 . Accumulator 12 is fixed to the outer peripheral surface of housing 2 via bracket 14 . The accumulator 12 is provided with the aforementioned suction pipe 11 for drawing the internal refrigerant into the compressor main body 10 . The suction pipe 11 connected to the accumulator 12 is connected to the suction port 25 through the opening 24 of the housing 2 . The accumulator 12 supplies the gas phase of refrigerant to the rotary compressor 6 through the suction pipe 11 .

The electric motor 5 is housed in the center of the housing 2 in the vertical direction. The electric motor 5 has a rotor 51 and a stator 52 . The rotor 51 is fixed to the outer peripheral surface of the rotary shaft 3 and arranged above the rotary compression section 6 . The stator 52 is arranged so as to surround the outer peripheral surface of the rotor 51 and is fixed to the inner surface 21 a of the main body portion 21 of the housing 2 .
A power source (not shown) is connected to the electric motor 5 configured as described above. The electric motor 5 is configured to rotate the rotating shaft 3 with electric power from this power supply.

The upper bearing 4A and the lower bearing 4B are arranged so as to sandwich the rotary compression portion 6 from above and below. The upper bearing 4</b>A and the lower bearing 4</b>B are partially made of a resin material, are provided separately from the cylinder 60 of the rotary compression unit 6 , and are fixed to the cylinder 60 with bolts 61 .
The rotating shaft 3 is rotatably supported around the rotation axis O by an upper bearing 4A and a lower bearing 4B.
The portions of the upper bearing 4A and the lower bearing 4B that are made of a resin material are hatched with lines of two different thicknesses in FIG. It is the part which does not oppose. Portions of the upper bearing 4A and the lower bearing 4B that are not made of a resin material are made of a metal material.

More specifically, the upper bearing 4A includes a cylindrical portion 4Aa having a cylindrical shape centered on the rotation axis O, and a lower portion of the cylindrical portion 4Aa which is integrally provided and extends radially outward from the cylindrical portion 4Aa. It has a flange portion 4Ab that protrudes.
A metallic ring 4H having a tubular shape centered on the rotation axis O is fitted to the inner surface of the tubular portion 4Aa.
The flange portion 4Ab faces the compression chamber 60A and covers the compression chamber 60A from above. An inner concave portion 4Ac is formed in the flange portion 4Ab at a radially inner position upward and annularly concave about the rotation axis O. As shown in FIG. A metal ring 4C having an annular shape about the rotation axis O is fitted in the inner recess 4Ac. The inner surface of the ring 4H provided on the cylindrical portion 4Aa and the inner surface of the ring 4C provided on the flange portion 4Ab are flush with each other and face the rotating shaft 3. As shown in FIG. Further, the lower surface of the ring 4C provided on the flange portion 4Ab forms part of the inner surface that forms the compression chamber 60A by covering the compression chamber 60A from above.
The flange portion 4Ab is further formed with an outer recess 4Ad that is recessed upward at a radially outer position with respect to the inner recess and that is annularly recessed about the rotation axis O. As shown in FIG. A seal 4E, which will be described later, is provided in the outer concave portion 4Ad.
In this embodiment, first, the resin material portion of the upper bearing 4A is formed using, for example, extrusion molding, injection molding, or print molding using a 3D printer. After that, metal rings 4C and 4H are fitted to the inner surfaces of the cylindrical portion 4Aa and the flange portion 4Ab to form the upper bearing 4A.

Similarly, the lower bearing 4B includes a cylindrical portion 4Ba having a cylindrical shape centered on the rotation axis O, and a flange portion integrally provided on the upper portion of the cylindrical portion 4Ba and protruding radially outward from the cylindrical portion 4Ba. 4Bb.
A metal ring 4J having a tubular shape centered on the rotation axis O is fitted to the inner surface of the tubular portion 4Ba.
The flange portion 4Bb faces the compression chamber 60A and covers the compression chamber 60A from below. An inner concave portion 4Bc is formed in the flange portion 4Bb at a radially inner position downward and annularly concave about the rotation axis O. As shown in FIG. A ring-shaped metal ring 4D centered on the rotation axis O is fitted in the inner recess 4Bc. The inner surface of the ring 4J provided on the cylindrical portion 4Ba and the inner surface of the ring 4D provided on the flange portion 4Bb are flush with each other and face the rotating shaft 3. As shown in FIG. The upper surface of the ring 4D provided on the flange portion 4Bb forms part of the inner surface that forms the compression chamber 60A by covering the compression chamber 60A from below.
The flange portion 4Bb is further formed with an outer recess 4Bd that is recessed downward at a radially outer position with respect to the inner recess and that is annularly recessed about the rotation axis O. As shown in FIG. A seal 4F, which will be described later, is provided in the outer concave portion 4Bd.
In this embodiment, first, the resin material portion of the upper bearing 4A is formed using, for example, extrusion molding, injection molding, or print molding using a 3D printer. After that, the upper bearing 4A is formed by fitting metal rings 4D and 4J to the inner surfaces of the tubular portion 4Aa and the flange portion 4Ab.

The rotary compression part 6 is arranged at the bottom inside the housing 2 below the electric motor 5 . The rotary compression section 6 has a cylinder 60 , an eccentric shaft section 62 and a piston rotor 63 .

The cylinder 60 has a compression chamber 60A, a suction hole 60B, and a discharge hole (not shown). The compression chamber 60A is formed inside the cylinder 60 . The compression chamber 60A accommodates the piston rotor 63 . A part of the cylinder 60 is made of a resin material.
The portion of the cylinder 60 that is made of a resin material is the portion hatched with lines of two different thicknesses in FIG. 2, and is the portion that does not face the compression chamber 60A.
In this embodiment, first, the resin material portion of the cylinder 60 is formed using, for example, extrusion molding, injection molding, or print molding using a 3D printer. After that, the cylinder 60 is formed by fitting a metal ring 4G inside the resin material portion. As a result, the inner surface facing radially inward forming the compression chamber 60A in the cylinder 60 is made of a metal material, and the other portions are made of a resin material.
A seal 4E is provided on the side of the upper bearing 4A at a position where the upper surface of the resin material portion of the cylinder 60 and the resin material portion of the upper bearing 4A face each other. A seal 4F is provided on the side of the lower bearing 4B at a position facing the resin material portion.

Resin materials that can be applied to the cylinder 60, the upper bearing 4A, and the lower bearing 4B include lightweight, heat-resistant, and high-strength materials such as PBT (polybutylene terephthalate), PPS (polyphenylene sulfide), and PEEK (polyethylene sulfide). ether ether ketone) resins.

The cylinder 60 partially made of resin is fixed to the inner surface 21 a of the main body 21 of the housing 2 . Reference P in FIG. 3 indicates a fixing portion between the housing 2 and the cylinder 60 . As a method for fixing the cylinder 60 to the housing 2, shrink fitting, cooling fitting, or resin melting can be employed.

The eccentric shaft portion 62 is provided at the lower end portion of the rotating shaft 3 and is provided inside the piston rotor 63 so as to be offset in a direction orthogonal to the central axis of the rotating shaft 3 .
The piston rotor 63 has a cylindrical shape with an outer diameter smaller than the inner diameter of the cylinder 60 , is arranged inside the cylinder 60 , and is inserted into and fixed to the eccentric shaft portion 62 . The piston rotor 63 rotates eccentrically with respect to the rotation axis O as the rotation shaft 3 rotates.

The suction hole 60B is a hole that allows the refrigerant to flow into the cylinder 60 .
Refrigerant compressed by the rotary compression section 6 is discharged to the discharge hole (not shown) into the internal space of the housing 2 which has an intermediate pressure.

As shown in FIG. 3, the cylinder 60 is provided with a blade 64 that divides the compression chamber 60A into two. A blade groove 65 extending in the radial direction is formed in the cylinder 60 . The blade 64 is slidably guided by the inner surface 65a of the blade groove 65 and is held so as to move toward and away from the piston rotor 63 . A base end portion 64b on the radially outer side of the blade 64 is elastically pressed by a compression spring (not shown), and the tip end portion 64a is always pressed against the outer peripheral surface 63a of the piston rotor 63. ing.

A metal material layer 66 of the cylinder 60 partially made of resin is formed on an inner surface 65 a of the blade groove 65 , which is a sliding portion with the blade 64 .

The eccentric shaft portion 62 has an outer diameter slightly smaller than the inner diameter of the piston rotor 63 . As a result, when the rotating shaft 3 rotates, the eccentric shaft portion 62 turns around the rotating shaft 3 and the piston rotor 63 eccentrically rolls within the cylinder 60 . At this time, since the blade 64 is pressed by a compression spring (not shown), the tip portion 64 a moves forward and backward following the movement of the piston rotor 63 and is always pressed against the piston rotor 63 .

In such a compressor 1, refrigerant is taken into the accumulator 12, the refrigerant is separated into gas and liquid in the accumulator 12, and the gas phase is sent from the suction pipe 11 through the suction port 25 of the cylinder 60 to the cylinder. It is supplied to the compression chamber 60A, which is the internal space of 60.
The eccentric rotation of the piston rotor 63 gradually reduces the volume of the compression chamber 60A, compressing the refrigerant. A discharge hole (not shown) for discharging the refrigerant is formed at a predetermined position of the cylinder 60, and the discharge hole is provided with a reed valve (not shown). As a result, when the pressure of the compressed refrigerant increases, the reed valve is pushed open to discharge the refrigerant to the outside of the cylinder 60 . The discharged refrigerant is discharged from a discharge pipe 13 provided at the top of the housing 2 to an external pipe (not shown).

Next, the effects of the rotary compressor described above will be specifically described with reference to the drawings.
In the compressor 1 according to the present embodiment, as shown in FIGS. 1, 2, and 3, the cylinder 60, the upper bearing 4A, and the lower bearing 4B, which are heavy even in the rotary compressor 1, are partially made of a resin material. As a result, the weight of the rotary compressor 1 can be reduced.

In the rotary compressor 1 according to this embodiment described above, the overall weight of the compressor 1 can be reduced.

In addition, since the portions of the upper bearing 4A and the lower bearing 4B facing the rotation shaft 3 and the portions facing the compression chamber 60A are made of a metal material, the compression chamber 60A in the upper bearing 4A and the lower bearing 4B is It is possible to improve the wear resistance against the compressed gas on the inner surface facing the .
Furthermore, by forming the portion of the cylinder 60 facing the compression chamber 60A from a metal material, it is possible to improve the wear resistance of the compressed gas on the inner surface of the cylinder and the components inside the compression chamber 60A.

Further, by providing the seal 4E or the seal 4F on the side of the upper bearing 4A or the lower bearing 4B at the position where the resin material portion of the cylinder 60 and the resin material portion of the upper bearing 4A or the lower bearing 4B face each other, It is possible to provide the contact portion of the contact with a sealing property equivalent to contact between metal materials.

Furthermore, the housing 2, the rotary shaft 3, the upper bearing 4A, the lower bearing 4B, the electric motor 5, the rotary compression section 6 (the cylinder 60, the eccentric shaft section 62, the piston rotor 63), the shape and size of the accumulator 12, etc. can be set to any suitable configuration.

[Second embodiment]
FIG. 4 shows a horizontal sectional view of a plane orthogonal to the central axis of the cylinder 160 of the rotary compressor 1A (hereinafter simply referred to as the compressor 1A) according to the second embodiment of the present invention. In the compressor 1A, in addition to the configuration of the first embodiment, in the cylinder 160, in the vicinity of the center in the direction of the rotating shaft 3, between the outer peripheral surface and the inner peripheral surface, an annular blade is formed around the rotating shaft 3 A cavity 67 is provided avoiding the groove 65, and the cavity 67 is filled with a filler 68 that is a resin material. Cylinder 160 is made of a metal material except filler 68 . The filling material 68 is formed by injecting a resin material from the filling port 69 .

Compressor 1A can reduce the weight of cylinder 160 while maintaining strength by forming only the inside of cavity 67 with filler 68 that is a resin material.

In this embodiment, in order to provide the cavity 67, a portion away from the surface of the cylinder 160 facing the upper bearing 4A or the lower bearing 4B in the direction of the rotating shaft 3 is cut. 4A or the surface facing the lower bearing 4B may be cut so as to form an annular groove around the rotating shaft 3 avoiding the blade groove 65 . In that case, the cylinder 160 is formed by fitting a resin material molded into a shape that fits into the groove.

Forming a groove in the surface of the cylinder 160 facing the upper bearing 4A or the lower bearing 4B facilitates processing.

Although the embodiments of the rotary compressor according to the present invention have been described above, the present invention is not limited to the above-described embodiments, and can be modified as appropriate without departing from the scope of the invention.

For example, in the present embodiment, the upper bearing 4A and the lower bearing 4B are partially made of a resin material, but they may be entirely made of a resin material.
In this case, the weight of both the upper bearing and the lower bearing, which are entirely made of a resin material, can be reduced, so that the weight of the entire rotary compressor can be further reduced.

In addition, it is possible to appropriately replace the components in the above-described embodiments with well-known components without departing from the scope of the present invention, and the above-described embodiments may be combined as appropriate.

1 compressor (rotary compressor)
2 housing 3 rotating shaft 4A upper bearing 4B lower bearing 5 electric motor 6 rotary compression section 10 compressor main body 12 accumulator 21 main body 21a inner surface 60 cylinder 60A compression chamber 62 eccentric shaft portion 63 piston rotor 64 blade 65 blade groove 65a inner surface 66 metal Material layer O Axis of rotation P Fixed part

Claims (3)

a housing;
a rotating shaft extending vertically within the housing;
a cylinder having therein a compression chamber through which the rotating shaft is inserted;
An upper bearing and a lower bearing that rotatably support the rotating shaft and are fixed above and below the cylinder,
A part of the cylinder is made of a resin material ,
The upper bearing covers the compression chamber from above,
The lower bearing covers the compression chamber from below,
At least a portion of at least one of the upper bearing and the lower bearing is made of a resin material,
inner surfaces of the upper bearing and the lower bearing facing the rotating shaft are formed of a metal material;
A rotary compressor , wherein all inner surfaces of the upper bearing and the lower bearing facing the compression chamber are made of a metal material . 2. The cylinder according to claim 1 , wherein a seal is provided at a position where a portion of the cylinder made of the resin material and a portion made of the resin material of at least one of the upper bearing and the lower bearing contact each other. rotary compressor. 3. The rotary compressor according to claim 1, wherein an inner surface forming said compression chamber of said cylinder is made of a metal material.

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