EP4242462A1

EP4242462A1 - Rotary compressor

Info

Publication number: EP4242462A1
Application number: EP21903371.9A
Authority: EP
Inventors: Fumiya HAMAGUCHI; Kana Sakon; Ryoji OKABE; Hitoshi Tamaki; Takuma YAMASHITA; Norihisa Horaguchi
Original assignee: Mitsubishi Heavy Industries Thermal Systems Ltd
Current assignee: Mitsubishi Heavy Industries Thermal Systems Ltd
Priority date: 2020-12-11
Filing date: 2021-12-06
Publication date: 2023-09-13
Also published as: EP4242462A4; WO2022124271A1; JP2022093072A

Abstract

A rotary compressor (1) includes a hermetic housing (2) that forms an outer shell, an electric motor (5), a compression mechanism (6) accommodated in the hermetic housing (2) and configured to compress a refrigerant by using a driving force from the electric motor (5), and a drive shaft (14) connecting the electric motor (5) and the compression mechanism (6) and configured to rotate about a center axis extending in a vertical direction. The compression mechanism (6) includes an upper rotor (33) connected to the drive shaft (14) and accommodated in an upper cylinder chamber (31), an upper cylinder main portion (34) defining an outer side of the upper cylinder chamber (31) in a radial direction, and an upper bearing portion (35) rotatably supporting the drive shaft (14) and defining the upper cylinder chamber (31) in the vertical direction. The compression mechanism compresses the refrigerant between the rotating upper rotor (33) and the upper cylinder main portion (34). The upper bearing portion (35) and the upper cylinder main portion (34) are formed of a composite material made by reinforcing a resin with reinforced fibers.

Description

Technical Field

The present disclosure relates to a rotary compressor.

Background Art

A rotary compressor is known as a compressor used in an air conditioner or the like (e.g., Patent Document 1). Patent Document 1 discloses a rotary compressor including a motor accommodated in a hermetic container, a rotary compression mechanism driven by the motor, and a drive shaft that transmits a driving force of the motor to the compression mechanism. The rotary compression mechanism compresses a refrigerant by causing a roller connected to the drive shaft to rotate in a cylinder chamber. The cylinder chamber is defined by a cylinder main body, bearings disposed above and below the cylinder main body for supporting the drive shaft, and a separator.

Citation List

Patent Literature

Patent Document 1: JP 2016-160911 A

Summary of Invention

Technical Problem

In such a rotary compressor, in a case where the bearings and/or the cylinder main body (hereinafter, referred to as "bearing and/or the like") defining the cylinder chamber are/is formed of a metal material, each member may be damaged or noise may be generated when a rotor rotationally moving in the cylinder chamber comes into contact with the bearing and/or the like. On the other hand, when a large gap is formed between the rotor and the bearing and/or the like, the refrigerant may leak from the gap, and thus compression efficiency may be reduced. Therefore, the gap formed between the rotor and the bearing and/or the like needs to be strictly controlled. For this reason, the bearing and/or the like need(s) to be manufactured with high accuracy, which makes it difficult to manufacture the bearing and/or the like.
The present disclosure has been made in view of such circumstances, and an object thereof is to provide a rotary compressor that can facilitate a process of manufacturing a bearing or the like.

Solution to Problem

In order to solve the problem described above, a rotary compressor of the present disclosure employs the following means.
A rotary compressor according to an aspect of the present disclosure includes a housing that forms an outer shell, a drive source, a compression mechanism accommodated in the hermetic housing and configured to compress a refrigerant by using a driving force from the drive source, and a drive shaft connecting the drive source and the compression mechanism and configured to rotate about a center axis extending in a predetermined direction. The compression mechanism includes a rotor connected to the drive shaft and accommodated in a cylinder chamber, a cylinder defining an outer side of the cylinder chamber in a radial direction, and a bearing rotatably supporting the drive shaft and defining the cylinder chamber in the predetermined direction. The refrigerant is compressed between the rotor being rotated and the cylinder. The bearing and/or the cylinder are/is formed of a composite material made by reinforcing a resin with reinforced fibers.

Advantageous Effects of Invention

According to the present disclosure, a process of manufacturing a bearing and/or the like can be facilitated.

Brief Description of Drawings

FIG. 1 is a vertical cross-sectional view of a compressor according to an embodiment of the present disclosure.
FIG. 2 is a perspective view of an upper bearing cylinder portion provided in the rotary compressor illustrated in FIG. 1.
FIG. 3 is a vertical cross-sectional perspective view of a rotary compression mechanism provided in the rotary compressor illustrated in FIG. 1.
FIG. 4 is a vertical cross-sectional view of the upper bearing cylinder portion illustrated in FIG. 2.
FIG. 5 is a perspective view illustrating a metal bushing illustrated in FIG. 4.
FIG. 6 is a perspective view of the upper bearing cylinder portion provided in the rotary compressor illustrated in FIG. 1.
FIG. 7 is an enlarged view of a main part in FIG. 6.
FIG. 8 is an enlarged view of a main part in FIG. 6.
FIG. 9 is a diagram illustrating a modification example of FIG. 7.
FIG. 10 is a plan view of a separator plate provided in the rotary compressor illustrated in FIG. 1.
FIG. 11 is a schematic perspective view illustrating a bolt for screwing the upper bearing cylinder portion and the separator plate provided in the rotary compressor illustrated in FIG. 1.
FIG. 12 is a diagram illustrating a modification example of FIG. 1.

Description of Embodiments

An embodiment of a rotary compressor according to the present disclosure will be described below with reference to the drawings.
As illustrated in FIG. 1, a rotary compressor 1 includes a hermetic housing (case) 2 having a cylindrical shape that forms an outer shell. An upper portion and a lower portion of the hermetic housing 2 are hermetically sealed by covers 3 and 4, respectively. An electric motor 5 is disposed at an upper portion of the hermetic housing 2, and a compression mechanism 6 driven by the electric motor (drive source) 5 is disposed at a lower portion of the hermetic housing 2. The rotary compressor 1 is an electric compressor having a hermetic structure. A plurality of mounting brackets 7 are provided on an outer periphery of the lower portion of the hermetic housing 2, and a discharge pipe 8 is disposed at the upper portion of the hermetic housing 2 penetrating the upper cover 3, so that a high-pressure refrigerant gas compressed by the compression mechanism 6 and discharged into the hermetic housing 2 can be delivered to the outside of the compressor (refrigeration cycle).
An accumulator (not illustrated) is integrally assembled to an outer peripheral portion of the hermetic housing 2. The accumulator separates a liquid portion such as oil and liquid coolant contained in a low-pressure refrigerant gas returned from the refrigeration cycle so that only a gas portion is sucked into the compression mechanism 6 via a suction pipe 10.
The electric motor 5 includes a stationary element 12 and a rotating element 13, and the stationary element 12 is fixed and disposed at an inside surface of the hermetic housing 2 by shrink fitting, press fitting, or the like. On the other hand, the rotating element 13 is integrally joined to a drive shaft 14, and a rotational driving force of the rotating element 13 can be transmitted to the compression mechanism 6 via the drive shaft 14. At a lower portion of the drive shaft 14, an upper eccentric portion 15 and a lower eccentric portion 16 are disposed at two upper and lower positions at a predetermined interval in an axial direction with a phase shift of 180 degrees, corresponding to an upper compression mechanism 30 and a lower compression mechanism 60 of the compression mechanism 6 to be described later. The drive shaft 14 is a substantially cylindrical member and is disposed such that a center axis thereof extends in the vertical direction. The drive shaft 14 connects the electric motor 5 and the compression mechanism 6. The drive shaft 14 rotates about the center axis by the driving force of the electric motor 5.
Next, the compression mechanism 6 according to the present embodiment will be described in detail.
The compression mechanism 6 is a two-cylinder type rotary compression mechanism including the upper compression mechanism 30 and the lower compression mechanism 60. The compression mechanism 6 also includes a separator plate (separator) 50 disposed between the upper compression mechanism 30 and the lower compression mechanism 60. In the following description, "radial direction" means a radial direction with reference to the center axis of the drive shaft 14.
The upper compression mechanism 30 includes, in the interior of the upper compression mechanism 30, an upper bearing cylinder portion 32 that defines an upper cylinder chamber (cylinder chamber) 31, and an upper rotor (rotor) 33 connected to the drive shaft 14 and accommodated in the upper cylinder chamber 31.
As illustrated in FIGS. 1 and 2, the upper bearing cylinder portion 32 includes an upper cylinder main portion 34 (cylinder) that defines an outer side of the upper cylinder chamber 31 in the radial direction, and an upper bearing portion (bearing) 35 that rotatably supports the drive shaft 14 and defines an upper side of the upper cylinder chamber 31. That is, the upper cylinder main portion 34 and the upper bearing portion 35 are integrally formed. The upper bearing cylinder portion 32 is entirely formed of a composite material made by reinforcing a resin with short fibers (hereinafter referred to as a "short fiber composite material"). The short fibers are, for example, glass fibers or carbon fibers having a fiber length of about 0. 1 mm to several millimeters.
Note that "integrally formed" does not mean that the upper bearing portion 35 and the upper cylinder main portion 34 are formed as separate members and then fixed to each other by a fastener, welding, or the like to be integrated with each other, but means that the upper bearing portion 35 and the upper cylinder main portion 34 are formed of the same material and thereby integrated with each other without a joint or the like. In the present embodiment, the upper bearing portion 35 and the upper cylinder main portion 34 of the upper bearing cylinder portion 32 are integrally formed by injection molding. The method of forming the upper bearing cylinder portion 32 is only an example and is not limited to injection molding.
As illustrated in FIG. 1, the upper bearing portion 35 rotatably supports the drive shaft 14. As illustrated in FIGS. 2 to 4, the upper bearing portion 35 integrally includes a cylindrical portion 35a into which the drive shaft 14 is inserted, a plurality of ribs 35b each having a plate shape and projecting in the radial direction from an outside surface of the cylindrical portion 35a, and an annular portion 35c having a plate shape and extending in the radial direction from a lower end of the cylindrical portion 35a. The cylindrical portion 35a, the ribs 35b, and the annular portion 35c have substantially the same thickness.
The cylindrical portion 35a is disposed such that the center axis thereof coincides with the center axis of the drive shaft 14. As illustrated in FIG. 4, a step part with a varying inside diameter is formed at an inside surface of the cylindrical portion 35a. Two metal bushings (bearing wear-resistant portions) 36 are disposed inside the cylindrical portion 35a in contact with the step part. Note that the metal bushings 36 are omitted in FIGS. 1 to 3 for convenience of illustration. The metal bushings 36 are disposed between the cylindrical portion 35a and the drive shaft 14.
As illustrated in FIG. 5, each metal bushing 36 is a cylindrical member. The metal bushing 36 is formed of a metal material (e.g., cast iron, an aluminum alloy, or a copper alloy). Two notch portions 36a recessed inward in the radial direction are formed in an outside surface of the metal bushing 36. The two notch portions 36a are disposed at equal intervals in the circumferential direction. Each notch portion 36a is formed extending from one end of the metal bushing 36 in the vertical direction to a central portion of the metal bushing 36. A stopper portion 36b having a planar shape is disposed at the other end of each notch portion 36b in the vertical direction. The cylindrical portion 35a includes an engaging portion (not illustrated) that engages with the notch portion 36a. Rotation of the metal bushing 36 can be restricted by the engagement between the notch portion 36a and the engaging portion. In addition, movement of the metal bushing 36 in the vertical direction is restricted by the contact between the engaging portion and the stopper portion 36b, and thus removal of the metal bushing 36 from the cylindrical portion 35a can be prevented.
As illustrated in FIG. 4, the metal bushing 36 is disposed at upper and lower portions of the cylindrical portion 35a. That is, the metal bushing 36 is not disposed at a central portion of the cylindrical portion 35a. The length in the vertical direction of a region where the metal bushing 36 is not disposed is set to be 20% to 30% of the length in the vertical direction of the cylindrical portion 35a. Note that the length of the region where the metal bushing 36 is not disposed is only an example, and is not limited to the above-described numerical values.
When the upper bearing cylinder portion 32 is injection-molded, the metal bushing 36 can be integrally molded with a bearing cylinder portion by being set in a mold before resin is injected. Manufacturing costs can be reduced by the integral molding described above.
The plurality of ribs 35b are arranged side by side in the circumferential direction of the cylindrical portion 35a so as not to be largely biased. Each rib 35b protrudes from an outside surface of the cylindrical portion 35a substantially over the entire range of the cylindrical portion 35a in the vertical direction. Each rib 35b is formed to protrude longer toward the lower side. A lower end of each rib 35b is connected to an upper surface of the annular portion 35c. An outer end in the radial direction of a lower portion of each rib 35b is connected to an inside surface of an outer frame portion 34c of the upper cylinder main portion 34 to be described later. Each rib 35b has a shape in which a substantially triangular member is connected to the top of a substantially rectangular member in a side view. A side surface (a surface intersecting a plate surface) of the rectangular member and a side surface of the triangular member are smoothly connected to each other such that a connected portion forms a curved surface.
In addition, a junction portion 37 is connected to a predetermined rib 35b. The junction portion 37 defines a first bolt hole 37a (screw hole) into which a bolt 38 is inserted. In other words, the first bolt hole 37a is formed on a predetermined rib 35b. A plurality of junction portions 37 are formed.
As illustrated in FIG. 1, the first bolt hole 37a extends through the upper bearing cylinder portion 32. The first bolt hole 37a communicates with a second bolt hole 52 formed in a separator plate 50 to be described later. The upper bearing cylinder portion 32 and the separator plate 50 are screwed and fixed to each other by the bolts 38 inserted into the first bolt holes 37a and the second bolt holes 52.
As illustrated in FIGS. 3 and 4, the annular portion 35c is an annular member having an opening formed at a substantially central portion thereof, and the drive shaft 14 is to be inserted through the opening. The annular portion 35c defines an upper side of the upper cylinder chamber 31 and defines an upper side of a second flow path 42 formed in the upper cylinder main portion 34 to be described later.
Next, the structure of the upper cylinder main portion 34 will be described with reference to FIGS. 1 to 4 and FIGS. 6 to 9. In FIGS. 6 to 9, the upper cylinder main portion 34 is illustrated upside down for convenience of explanation. That is, in FIGS. 6 to 9, the lower side of the drawing corresponds to the vertically upper side, and the upper side of the drawing corresponds to the vertically lower side.
As illustrated in FIGS. 3 and 4, the upper cylinder main portion 34 integrally includes a defining portion 34a having a cylindrical shape that defines an outer side of the upper cylinder chamber 31 in the radial direction, a contact portion 34b having a plate shape and extending outward in the radial direction from a lower end of the defining portion 34a, and the outer frame portion 34c having a cylindrical shape, being bent at a substantially right angle from an outer end portion of the contact portion 34b in the radial direction, and extending upward from the outer end portion. The defining portion 34a, the contact portion 34b, and the outer frame portion 34c have substantially the same thickness. In addition, the plate thicknesses of the defining portion 34a and the like of the upper cylinder main portion 34 is substantially the same as the plate thicknesses of the ribs 35b and the like of the upper bearing portion 35.
An inside surface of the defining portion 34a defines the upper cylinder chamber 31. An upper end of the defining portion 34a is connected to a bottom surface of an outer end portion of the annular portion 35c in the radial direction. A suction port 43 is formed in the defining portion 34a. The suction port 43 opens to the upper cylinder chamber 31.
A bottom surface of the contact portion 34b is in contact with a top surface of the separator plate 50. The junction portions 37 are formed in a top surface of the contact portion 34b.
The outer frame portion 34c is disposed outside the defining portion 34a in the radial direction. The outer frame portion 34c stands so as to face the defining portion 34a.
In the upper cylinder main portion 34, a second flow path 42 is formed between the defining portion 34a and the outer frame portion 34c, and the second flow path 42 is connected to a first flow path 41 formed in the separator plate 50, which will be described later. The second flow path 42 is a flow path having a substantially circular flow path cross-section extending in the vertical direction. A downstream end portion of the second flow path 42 is connected to the suction port 43 (suction port) formed in the defining portion 34a. Accordingly, a refrigerant flowing through the second flow path 42 flows into the upper cylinder chamber 31 via the suction port 43.
As illustrated in FIGS. 3 and 7, the suction port 43 is formed in a rectangular shape. Specifically, the suction port 43 has a rectangular shape in which a length in the vertical direction is longer than a length in a direction intersecting the vertical direction (that is, a rotational direction of the upper rotor 33).
An upper edge of the suction port 43 is defined by the upper bearing portion 35 and a lower edge thereof is defined by the separator. An edge of the suction port 43 in the rotational direction is defined by the defining portion 34a.
As illustrated in FIG. 6, the upper cylinder main portion 34 includes a blade (not illustrated) that partitions the upper cylinder chamber 31 into a suction side and a discharge side for a refrigerant, and a blade groove 44 that slidably accommodates the blade.
The blade is formed of a metal material. The blade is slidably fitted in the blade groove 44. The blade groove 44 is a groove extending in the radial direction and accommodates the blade. An inner end of the blade groove 44 in the radial direction is connected to the upper cylinder chamber 31. The blade groove 44 is disposed adjacent to the suction port 43.
As illustrated in FIG. 7, an end portion on the cylinder chamber side (an inner end portion in the radial direction) of a side wall surface of the blade groove 44 on the suction side (suction port 43 side) is entirely covered by a suction-side wear-resistant portion 45 in the vertical direction. As illustrated in FIG. 8, a side wall surface of the blade groove 44 on the discharge side (the side on which the suction port 43 is not provided) is covered by a discharge-side wear-resistant portion 46 over substantially the entire range in the radial direction. The suction-side wear-resistant portion 45 and the discharge-side wear-resistant portion 46 are formed of a metal material (e.g., cast iron, an aluminum alloy, or a copper alloy). The suction-side wear-resistant portion 45 and the discharge-side wear-resistant portion 46 include, at outer end portions thereof in the radial direction, protrusions 45a and 46a, respectively, that engage with recesses 45b and 46b of the upper cylinder main portion 34, respectively. With the engagement between the protrusions 45a and 46a and the recesses 45b and 46b, the suction-side wear-resistant portion 45 and the discharge-side wear-resistant portion 46 can be restricted from moving in the radial direction. Note that, in FIG. 6, the suction-side wear-resistant portion 45 and the discharge-side wear-resistant portion 46 are omitted for convenience of illustration.
Note that, in the foregoing, an example in which only the inner end portion in the radial direction of the side wall surface of the blade groove 44 on the suction side is covered by the suction-side wear-resistant portion 45 has been described, but the present disclosure is not limited thereto. For example, as illustrated in FIG. 9, the side wall surface of the blade groove 44 on the suction side may be covered by the suction-side wear-resistant portion 45 over substantially the entire range in the radial direction. In this case, by setting the suction-side wear-resistant portion 45 and the discharge-side wear-resistant portion 46 to the same shape, these wear-resistant portions can be integrated and the manufacturing cost thereof can be reduced.
As illustrated in FIG. 1, the upper rotor 33 is fitted to an outside surface of the upper eccentric portion 15. The center axis of the upper eccentric portion 15 is eccentric with respect to the center axis of the drive shaft 14. Thus, the upper rotor 33 revolves in the upper cylinder chamber 31 together with the rotation of the drive shaft 14. A refrigerant is compressed between the revolving upper rotor 33 and the upper cylinder main portion 34.
The separator plate 50 is a plate-like member formed of a metal material (e.g., cast iron). As illustrated in FIG. 10, the separator plate 50 is an annular member having an opening formed in a central portion thereof, and the drive shaft 14 is inserted into the opening. The separator plate 50 is fixed to an inside surface of the hermetic housing 2 by plug welding, caulking, or the like.
As illustrated in FIG. 3 and the like, the separator plate 50 separates the upper cylinder chamber 31 and a lower cylinder chamber. A top surface of the separator plate 50 defines a bottom side of the upper cylinder chamber 31. A bottom surface of the separator plate 50 defines a top side of the lower cylinder chamber.
A suction pipe insertion hole is formed in the separator plate 50 extending inward in the radial direction from a side surface of the separator plate 50. The suction pipe 10 that guides a refrigerant to the upper cylinder chamber 31 is inserted into the suction pipe insertion hole. The first flow path 41 is formed in the separator plate 50, extending through the separator plate 50 in the vertical direction. An upstream end of the first flow path 41 is connected to the suction pipe 10. A downstream end of the first flow path 41 is connected to an upstream end of the second flow path 42. The first flow path 41 and the second flow path 42 are connected to each other to form a single linear flow path extending in the vertical direction.
As illustrated in FIG. 1, the second bolt hole 52 communicating with the first bolt hole 37a is formed in the separator plate 50. The inside surface of the second bolt hole 52 is formed with a female thread that mates with a male thread of the bolt 38. The upper bearing cylinder portion 32 and the separator plate 50 are screwed and fixed to each other by the bolts 38 inserted into the first bolt holes 37a and the second bolt holes 52.
The lower compression mechanism 60 has a structure vertically symmetrical to the upper compression mechanism 30 with respect to the separator plate 50. Thus, a detailed description of the lower compression mechanism 60 will be omitted.
A refrigerant that has flowed into the first flow path 41 from the suction pipe 10 as indicated by an arrow Al in FIG. 3 flows through the first flow path 41 and the second flow path 42 and flows into the upper cylinder chamber 31 and the lower cylinder chamber from the suction port 43 as indicated by an arrow A2. The refrigerant compressed in the upper cylinder chamber 31 and the lower cylinder chamber is discharged into a discharge chamber (not illustrated) via a discharge port (not illustrated) and a discharge valve (not illustrated), discharged from the discharge chamber into the hermetic housing 2, and then guided to an upper portion of the hermetic housing 2 to be discharged to the refrigeration cycle side via the discharge pipe 8.
According to the present embodiment, the following operational effects are obtained. The effects of the upper compression mechanism 30 will be mainly described below, but, as a matter of course, the same effects as those of the upper compression mechanism 30 can also be obtained in the lower compression mechanism 60.
In the present embodiment, the upper bearing cylinder portion 32 defining the upper cylinder chamber 31 is formed of a short fiber composite material. The short fiber composite material is more likely to deform than a metal material or the like. Thus, when the upper rotor 33 that rotationally moves in the upper cylinder chamber 31 and the upper bearing cylinder portion 32 defining the upper cylinder chamber 31 come into contact with each other, the upper bearing cylinder portion 32 is likely to deform by a load applied from the upper rotor 33. At this time, the upper bearing cylinder portion 32 deforms by the load from the upper rotor 33 such that the contact with the upper rotor 33 is reduced. Thus, the contact between the upper bearing cylinder portion 32 and the upper rotor 33 can be reduced. In addition, since the deformation of the upper bearing cylinder portion 32 is caused by the contact with the upper rotor 33, the upper bearing cylinder portion 32 does not deform to such an extent that a gap formed between the upper bearing cylinder portion 32 and the upper rotor 33 becomes excessively large.
Thus, in the present embodiment, the contact between the upper bearing cylinder portion 32 and the upper rotor 33 can be reduced without strictly managing the gap formed between the upper bearing cylinder portion 32 and the upper rotor 33 in manufacturing the upper compression mechanism 30. Accordingly, the compression mechanism 6 can be manufactured more easily.
Note that the deformation of the upper bearing cylinder portion 32 includes deformation caused by the upper rotor 33 or the like cutting the upper bearing cylinder portion 32.
In addition, in a case where the bearing is formed of a metal material, when the drive shaft 14 comes into one-sided contact with the bearing, a local surface pressure may increase, and the reliability of the bearing may be decreased. On the other hand, in the present embodiment, since the upper bearing cylinder portion 32 is formed of a composite material, the upper bearing cylinder portion 32 deforms in accordance with the deformation of the drive shaft 14. Accordingly, the increase in the local surface pressure of the upper bearing cylinder portion 32 can be suppressed and the decrease in the reliability of the bearing function of the upper bearing portion 35 can be suppressed.
In a case where the bearing and the cylinder are formed of a metal material, it is conceivable to form the bearing and the cylinder by machining. When the bearing and/or the like are/is formed by machining, interference with a tool or the like needs to be considered, and thus the forming operation may become complicated. In addition, in processing a member having a complicated shape in which a bearing and a cylinder are integrated with each other, the forming operation may become further complicated.
On the other hand, in the present embodiment, the bearing and the cylinder are formed of a composite material. In molding the bearing and/or the like from the composite material, for example, the bearing and/or the like can be molded by injection molding or the like using a mold or the like, and thus no complicated work such as machining is needed. Thus, even a member having a complicated shape such as the upper bearing cylinder portion 32 in which the bearing and the cylinder are integrally formed can be easily molded.
In addition, in the present embodiment, since the bearing and the cylinder are integrally formed, the number of components can be reduced as compared to a case where the bearing and the cylinder are separate bodies. Accordingly, costs and time required for assembly work can be reduced.
Further, when the bearing and the cylinder are formed as separate bodies, the bearing and the cylinder need to be aligned so as to be coaxial with each other. However, when the bearing and the cylinder are integrally formed, alignment of the bearing and the cylinder can be eliminated.
Furthermore, since the bearing and the cylinder are integrally formed, by supporting the drive shaft 14 by the bearing, the position of the upper rotor 33 in the upper cylinder chamber 31 is also determined. As a result, variations in the gap formed between the upper cylinder portion and the upper rotor 33 can be reduced. Accordingly, fitting based on the actual dimensions of the cylinder and the bearing can be eliminated.
In the present embodiment, the upper bearing cylinder portion 32 is fixed to the separator plate 50, and the separator plate 50 is fixed to the hermetic housing 2. Accordingly, the drive shaft 14 is supported by the hermetic housing 2 via the upper bearing cylinder portion 32 and the separator plate 50. In addition, in the present embodiment, the separator plate 50 is formed of a metal material. A metal material is less likely to deform than a composite material or the like. As described above, since the drive shaft 14 is supported by the separator plate 50 formed of a metal material, which is less likely to deform, the drive shaft 14 can be made less likely to topple as compared to a case where the separator plate 50 is formed of a short fiber composite material. Accordingly, the contact between the rotating element 13 and the stationary element 12 due to the deformation of the drive shaft 14 can be made less likely to occur.
In addition, in the present embodiment, the compression mechanism 6 is fixed to the hermetic housing 2 by the separator plate 50 located at a central portion in the vertical direction. Thus, when compared to a case where the compression mechanism 6 is fixed to the hermetic housing 2 at an end portion in the vertical direction, a distance from a point of fixing to the hermetic housing 2 to each cylinder chamber in which the refrigerant is compressed is shorter. Accordingly, the deformation of the upper bearing cylinder portion 32 can be reduced.
In the present embodiment, the suction pipe 10 is connected to the separator plate 50 made of a metal material. As a result, deformation and deterioration of a connected member (separator plate 50) due to heat generated during the connection of the suction pipe 10 (e.g., heat associated with brazing or welding) can be reduced.
In addition, in the present embodiment, the suction pipe 10 is connected to the separator plate 50. Thus, the number of suction pipes 10 can be reduced as compared to a case where a plurality of suction pipes 10 connected to the respective cylinder chambers are provided. Accordingly, the number of components can be reduced, and thus costs and time required for assembly work can be reduced.
In the present embodiment, an upper edge of the suction port 43 is defined by the upper bearing cylinder portion 32 and a lower edge of the suction port 43 is defined by the separator plate 50. That is, when only the upper bearing cylinder portion 32 is viewed, the lower side of the suction port 43 is opened. Thus, a length of the suction port 43 in the vertical direction can be increased as compared to a case where a member for closing the lower side of the suction port 43 is provided, and thus the area of the suction port 43 can be increased accordingly.
In addition, for example, when the area of the suction port 43 is the same as in the case where a member for closing the lower side of the suction port 43 is provided, a length of the suction port 43 in a direction intersecting a predetermined direction (i.e., the rotational direction of the upper rotor 33) can be reduced in accordance with the increase in the length of the suction port 43 in the vertical direction. As a result, a time during which the suction port 43 is closed by the upper rotor 33 can be increased, and thus the compression efficiency for the refrigerant in the upper cylinder chamber 31 can be improved.
Further, since the lower side of the suction port 43 is opened in the upper bearing cylinder portion 32, when the upper bearing cylinder portion 32 is formed by injection molding and is removed upward from the mold, the upper bearing cylinder can be easily removed from the mold.
In the present embodiment, the junction portions 37 are connected to the corresponding ribs 35b. Thus, a load acting on the upper bearing portion 35 when the drive shaft 14 is about to incline can be transmitted to the separator plate 50 via the ribs 35b and the junction portions 37. Accordingly, since the drive shaft 14 can be supported by the separator plate 50 that is less likely to deform, deformation of the drive shaft 14 can be reduced.
In the present embodiment, the rib 35b is a plate-like member having a constant plate thickness and extends in the radial direction from an outside surface of the cylindrical portion 35a of the upper bearing portion 35. Thus, when viewed from above, a length (plate thickness) of the rib 35b in the circumferential direction is constant. Accordingly, for example, when the upper bearing cylinder portion 32 is formed by injection molding and is removed upward from the mold, the rib 35b and the mold do not interfere with each other, and thus the upper bearing cylinder portion 32 can be easily removed from the mold.
In addition, by providing the ribs 35b extending in the radial direction from the outside surface of the cylindrical portion 35a, it is possible to improve rigidity in a direction (inclination direction) in which the drive shaft 14 inclines with respect to a predetermined direction while minimizing product volume.
In the present embodiment, the plurality of ribs 35b are arranged at equal intervals in the circumferential direction of the cylindrical portion 35a. As a result, the rigidity of the cylindrical portion 35a in the inclination direction can be improved over the entire range in the circumferential direction. In addition, by providing the ribs 35b, thermal expansion or shrinkage of the upper bearing portion 35 is absorbed by the ribs 35b. Thus, inclination of the drive shaft 14 due to thermal expansion or shrinkage of the upper bearing portion 35 can be reduced.
Further, for example, in forming the upper bearing cylinder portion 32 by injection molding, when a short fiber composite material is caused to flow into a mold in a predetermined direction from a tip of the cylindrical portion 35a of the upper bearing portion 35, the ribs 35b function as inflow paths of the short fiber composite material. Accordingly, the composite material can easily and uniformly flow throughout the entire upper bearing cylinder portion 32.
Furthermore, while the short fiber composite material flows in the radial direction along the ribs 35b, each fiber contained in the short fiber composite material extends along an inflow direction. Since the inflow direction is substantially the same as the inclination direction of the drive shaft 14, rigidity with respect to the inclination direction of the drive shaft 14 can be improved.
In the present embodiment, the metal bushing 36 is disposed between the upper bearing portion 35 and the drive shaft 14. This improves a limit PV value, and thus the wear of the upper bearing portion 35 due to the rotation of the drive shaft 14 can be reduced.
In the present embodiment, the metal bushing 36 is disposed at both end portions of the upper bearing portion 35 in the vertical direction. That is, the metal bushing 36 is not disposed at a central portion of the upper bearing portion 35. Thus, when the drive shaft 14 deforms in the inclination direction, the upper bearing portion 35 is more likely to deform in response to the deformation of the drive shaft 14 as compared to a case where the metal bushing 36 is disposed over substantially the entire range of the upper bearing portion 35 in the vertical direction. That is, the metal bushings 36 are unlikely to restrict the deformation of the upper bearing portion 35. Since the upper bearing portion 35 deforms in response to the deformation of the drive shaft 14, even when the drive shaft 14 deforms, a surface pressure acting on the upper bearing portion 35 can be reduced, and thus the wear of the upper bearing portion 35 can be reduced.
In addition, since the volume of the metal bushings 36 is reduced as compared to a case where the metal bushing 36 is disposed over substantially the entire range of the upper bearing portion 35 in the vertical direction, the manufacturing cost of the metal bushing 36 can be reduced.
In the present embodiment, the suction-side wear-resistant portion 45 and the discharge-side wear-resistant portion 46 are disposed at the end portions of the blade groove 44 on the upper cylinder chamber 31 side. Thus, the wear of the upper cylinder main portion 34 due to the sliding of the blade can be reduced.
In addition, only the inner end portion in the radial direction of the side wall surface of the blade groove 44 on the suction side is covered by the suction-side wear-resistant portion 45. Thus, the upper cylinder portion is more likely to deform in response to a load from the blade as compared to a case where the wear-resistant portion is disposed over substantially the entire range of the cylinder groove. That is, the suction-side wear-resistant portion 45 is unlikely to restrict the deformation of the upper cylinder portion. Since the upper cylinder portion deforms responding to a load from the blade, a surface pressure acting on the upper cylinder portion can be reduced, and thus the wear of the upper cylinder portion can be reduced. Further, in this case, the volume of the suction-side wear-resistant portion 45 is reduced as compared to a case where the wear-resistant portion is disposed over substantially the entire range of the blade groove 44, and thus the manufacturing cost of the suction-side wear-resistant portion 45 can be reduced. Note that since the blade mainly comes into contact with only the inner end portion of the side wall surface on the suction side in the radial direction, the wear can be suitably reduced even though the wear-resistant portion covers only the inner end portion.
Note that the present disclosure is not limited to the above-described embodiments and can be modified as required without departing from the spirit of the disclosure.
For example, as illustrated in FIG. 11, a sleeve 65 may be disposed between the bolt 38 and the inside surface of the junction portion 37. The sleeve 65 is formed of a metal material (e.g., cast iron, an aluminum alloy, or a copper alloy). By disposing the sleeve 65 between the bolt 38 and the inside surface of the junction portion 37, a stress relaxation phenomenon can be suppressed, and thus a decrease in the axial force of the bolt 38 can be suppressed.
The sleeve 65 is disposed from the upper end of the junction portion 37 to a position above a lower end of the junction portion 37. That is, the sleeve 65 is not disposed up to the lower end of the junction portion 37. Thus, the sealing performance between the bolt 38 and the junction portion 37 can be increased as compared to a case where the sleeve 65 is disposed up to the lower end of the junction portion 37.
Note that, instead of providing the sleeve 65, the bolt 38 may be formed of aluminum. Aluminum has a linear expansion coefficient closer to the linear expansion coefficient of the short fiber composite material than iron. Thus, when the bolt 38 is formed of aluminum, a creep phenomenon can be suppressed as compared to a case where the bolt 38 is formed of iron.
In addition, as indicated by the broken line in FIG. 6, an excess thickness portion 66 may be disposed on the outer side in the radial direction of the suction port 43 of the upper bearing cylinder portion 32, protruding further outward in the radial direction than other regions.
A low-temperature refrigerant before compression is guided into the suction port 43. Thus, the temperature of a region near the suction port 43 is lower than the temperatures of other regions. The thermal expansion coefficient of the short fiber composite material is larger than that of metal or the like. Thus, in the upper bearing cylinder portion 32 formed of the short fiber composite material, a region near the suction port 43 may deform due to a difference in temperature with other regions. When the upper bearing cylinder portion 32 deforms, the adhesion between the upper bearing cylinder portion 32 and the separator plate 50 is reduced, and thus the refrigerant may leak from the upper cylinder chamber 31.
On the other hand, in the present embodiment, the upper bearing cylinder portion 32 is provided with the excess thickness portion 66 on the outer side of the suction port 43 in the radial direction. With the excess thickness portion 66, a region near the suction port 43 is less likely to deform. Accordingly, the deformation of the upper bearing cylinder portion 32 can be suppressed, and thus leakage of the refrigerant from the upper cylinder chamber 31 can be suppressed.
In the above embodiment, the rotary compressor 1 of a so-called two-cylinder type in which two cylinders are provided has been described, but the present disclosure is not limited thereto. For example, as illustrated in FIG. 12, a rotary compressor 70 of a so-called single-cylinder type in which only one cylinder is provided is conceivable. In the example of FIG. 12, a compression mechanism 71 includes an upper bearing 72, a lower bearing 73, and a cylinder main body portion 74. The upper bearing 72, the lower bearing 73, and the cylinder main body portion 74 are formed as separate bodies.
In the example of FIG. 12, the upper bearing 72 and/or the lower bearing 73 are/is formed of a short fiber composite material. The cylinder main body portion 74 is formed of a metal material. The cylinder main body portion 74 is fixed to the hermetic housing 2. The upper bearing 72 and the cylinder main body portion 74 are screwed and fixed to each other by a bolt 75. The lower bearing 73 and the cylinder main body portion 74 are also screwed and fixed to each other by a bolt 76.
Note that, in the above description, an example in which the upper bearing 72, the lower bearing 73, and the cylinder main body portion 74 are formed as separate bodies has been described, but the present disclosure is not limited thereto. For example, the upper bearing 72 and the cylinder main body portion 74 may be integrally formed of a composite material. In this case, the lower bearing 73 is formed of a metal material, and the lower bearing 73 is fixed to the hermetic housing 2. Alternatively, the lower bearing 73 and the cylinder main body portion 74 may be integrally formed of a composite material. In this case, the upper bearing 72 is formed of a metal material, and the upper bearing 72 is fixed to the hermetic housing 2.
The rotary compressor described in the above embodiment is understood as follows, for example.
A rotary compressor according to an aspect of the present disclosure includes a hermetic housing (2) that forms an outer shell, a drive source (5), a compression mechanism (6) accommodated in the hermetic housing and configured to compress a refrigerant by using a driving force from the drive source, and a drive shaft (14) connecting the drive source and the compression mechanism and configured to rotate about a center axis extending in a predetermined direction. The compression mechanism includes a rotor (33) connected to the drive shaft and accommodated in a cylinder chamber (31), a cylinder (34) defining an outer side of the cylinder chamber in a radial direction, and a bearing (35) rotatably supporting the drive shaft and defining the cylinder chamber in the predetermined direction. The compression mechanism compresses the refrigerant between the rotor being rotated and the cylinder. The bearing and/or the cylinder are/is formed of a composite material made by reinforcing a resin with reinforced fibers.
In the configuration described above, the bearing and/or the cylinder (hereinafter referred to as "bearing and/or the like") defining the cylinder chamber are/is formed of a composite material obtained by reinforcing a resin with reinforced fibers. The composite material is more likely to deform than another material such as a metal material. Thus, when the rotor, which rotationally moves in the cylinder chamber, and the bearing and/or the like defining the cylinder chamber come into contact with each other, the bearing and/or the like are/is likely to deform by a load applied from the rotor. At this time, the bearing and/or the like deforms by the load from the rotor such that the contact with the rotor is reduced. Thus, the contact between the bearing and/or the like and the rotor can be reduced. In addition, since the deformation of the bearing and/or the like is caused by the contact with the rotor, the bearing and/or the like does not deform to such an extent that a gap formed between the bearing and/or the like and the rotor becomes excessively large.
In this way, in the configuration described above, the contact between the bearing and/or the like and the rotor can be reduced without strictly managing the gap formed between the bearing and/or the like and the rotor in manufacturing the compression mechanism. Accordingly, manufacturing of the compression mechanism can be facilitated.
Note that the deformation of the bearing and/or the like includes deformation caused by the rotor cutting the bearing and/or the like.
In a rotary compressor according to an aspect of the present disclosure, the bearing and the cylinder are formed of the composite material, and the bearing and the cylinder are integrally formed.
In a case where the bearing and the cylinder are formed of a metal material, it is conceivable to form the bearing and the cylinder by machining. When the bearing and/or the like are/is formed by machining, interference with a tool or the like needs to be considered, and thus the forming operation may become complicated. In addition, in processing a member having a complicated shape in which a bearing and a cylinder are integrated with each other, the forming operation may become further complicated.
On the other hand, in the configuration described above, the bearing and the cylinder are formed of the composite material. In molding the bearing and/or the like from the composite material, for example, the bearing and/or the like can be molded by injection molding or the like using a mold or the like, and thus no complicated work such as machining is needed. Thus, even a member having a complicated shape in which the bearing and the cylinder are integrated can be easily molded.
In addition, in the configuration described above, since the bearing and the cylinder are integrally formed, the number of components can be reduced as compared to a case where the bearing and the cylinder are separate bodies. Accordingly, costs and time required for assembly work can be reduced.
Further, when the bearing and the cylinder are formed as separate bodies, the bearing and the cylinder need to be aligned so as to be coaxial with each other. However, when the bearing and the cylinder are integrally formed, alignment of the bearing and the cylinder can be eliminated.
Furthermore, by integrally forming the bearing and the cylinder and supporting the drive shaft with the bearing, relative positions of the cylinder and the rotor are also determined. As a result, variations in the gap formed between the cylinder and the rotor can be reduced. Accordingly, fitting based on the actual dimensions of the cylinder and the bearing can be eliminated.
Note that "integrally formed" does not mean that the bearing and the cylinder are formed as separate members and then fixed to each other by a fastener, welding, or the like, but means that the bearing and the cylinder are formed integrated with each other by, for example, injection molding.
In a rotary compressor according to an aspect of the present disclosure, the drive source includes a rotating element (13) fixed to the drive shaft and a stationary element (12) surrounding the rotating element, the compression mechanism includes a plurality of the cylinder chambers arranged in the predetermined direction and a plurality of the rotors respectively accommodated in the cylinder chambers, the cylinder chambers adjacent to each other in the predetermined direction are separated by a separator (50), the bearing and the cylinder integrally formed are fixed to the separator, and the separator is formed of a metal material and fixed to the housing.
In the configuration described above, the bearing is fixed to the separator, and the separator is fixed to the housing. Thus, the drive shaft is fixed to the housing via the bearing and the separator formed of a metal material. Further, in the configuration described above, the separator is formed of a metal material. A metal material is less likely to deform than a composite material or the like. As described above, since the drive shaft is supported by the separator formed of a metal material that is less likely to deform, the drive shaft can be made less likely to deform as compared to a case where the separator is formed of a composite material. Accordingly, the rotating element and the stationary element can be made less likely to come into contact with each other due to the deformation of the drive shaft.
In addition, in the configuration described above, the compression mechanism is fixed to the housing by the separator located at a relatively central portion in the predetermined direction. Thus, when compared to a case where the compression mechanism is fixed to the housing at an end portion in the predetermined direction, a distance from a point of fixing to the housing to each cylinder chamber in which the refrigerant is compressed is shorter. Accordingly, the deformation of the bearing, the cylinder, or the like can be reduced.
A rotary compressor according to an aspect of the present disclosure further includes a suction pipe (10) that guides the refrigerant to the compression mechanism, in which the suction pipe is connected to the separator, and the compression mechanism includes a refrigerant flow path (41, 42) that guides the refrigerant supplied from the suction pipe to the cylinder chamber.
In the configuration described above, the suction pipe is connected to the separator made of a metal material. As a result, deformation and deterioration of the connected member (the separator) due to heat generated during connection of the suction pipe (e.g., heat associated with brazing or welding) can be reduced.
In addition, in the configuration described above, the suction pipe is connected to the separator. Thus, the number of suction pipes can be reduced as compared to a case where a plurality of suction pipes respectively connected to the cylinder chambers are provided. Accordingly, the number of components can be reduced, and thus costs and time required for assembly work can be reduced.
In a rotary compressor according to an aspect of the present disclosure, the refrigerant flow path includes a downstream end portion connected to a suction port (43) opening to the cylinder chamber, and one side of the suction port in the predetermined direction is defined by the bearing and an other side of the suction port in the predetermined direction is defined by the separator.
In the configuration described above, the one side of the suction port in the predetermined direction is defined by the bearing, and the other side of the suction port in the predetermined direction is defined by the separator. That is, when only an integrated body of the bearing and the cylinder is viewed, the other side of the suction port in the predetermined direction is open. Accordingly, a length of the suction port in the predetermined direction can be increased as compared to a case where a member for closing the other side of the suction port is provided, and thus the area of the suction port can be increased. In addition, for example, when the area of the suction port is the same as in the case where a member for closing the other side of the suction port is provided, a length of the suction port in a direction intersecting the predetermined direction (i.e., a rotational direction of the rotor) can be reduced in accordance with the increase in the length of the suction port in the predetermined direction. As a result, a time during which the suction port is closed by the rotor can be increased, and thus the compression efficiency for the refrigerant in the cylinder chamber can be improved.
Further, since the other side of the suction port in the predetermined direction is opened in the integrated body of the bearing and the cylinder, for example, when the bearing and the cylinder are integrally formed by injection molding and are removed in a direction toward the one side in the predetermined direction from a mold, the bearing and the cylinder can be easily removed from the mold.
A rotary compressor according to an aspect of the present disclosure further includes a screw member (38) configured to fix the bearing and the cylinder integrally formed and the separator, in which the bearing and the cylinder integrally formed include a rib (35b) that reinforces the bearing and a junction portion (37) defining a screw hole through which the screw member is inserted, and the junction portion is connected to the rib.
In the configuration described above, the junction portion is connected to the rib. Thus, a load acting on the bearing when the drive shaft is about to incline can be transmitted to the separator plate via the rib and screw member. Accordingly, the drive shaft can be supported by the separator plate that is less likely to deform, and thus deformation of the drive shaft can be reduced.
In a rotary compressor according to an aspect of the present disclosure, a sleeve (65) formed of a metal material is disposed between an inside surface of the screw hole and the screw member.
In the configuration described above, the sleeve formed of a metal material is disposed between the inside surface of the screw hole and the screw member. Accordingly, a creep phenomenon can be suppressed, and thus a decrease in the axial force of the screw member can be suppressed.
In a rotary compressor according to an aspect of the present disclosure, the rib is a plate-like member having a constant plate thickness and extends in a radial direction from an outside surface of the bearing having a cylindrical shape.
In the configuration described above, the rib is a plate-like member having a constant plate thickness and extends in the radial direction from the outside surface of the bearing having a cylindrical shape. Thus, when viewed from the predetermined direction (an extending direction of the drive shaft), a length (plate thickness) of the rib in the circumferential direction is constant. Accordingly, for example, when the bearing and the cylinder are integrally formed by injection molding and are removed in the predetermined direction from a mold, the rib and the mold do not interfere with each other, and thus the bearing and the cylinder can be easily removed from the mold.
In addition, by providing the rib extending in the radial direction from the outside surface of the bearing, it is possible to improve rigidity in a direction (inclination direction) in which the drive shaft inclines with respect to the predetermined direction while minimizing a product volume.
In a rotary compressor according to an aspect of the present disclosure, a plurality of the ribs are provided, and the plurality of ribs are arranged side by side at predetermined intervals in the circumferential direction of the bearing.
In the configuration described above, the plurality of ribs are arranged side by side at predetermined intervals in the circumferential direction of the bearing. Thus, rigidity in a plurality of inclination directions can be improved. In addition, by providing the ribs, thermal expansion or shrinkage of the bearing is absorbed by the ribs. Thus, inclination of the drive shaft due to thermal expansion or shrinkage of the bearing can be reduced.
Further, for example, in integrally forming the bearing and the cylinder by injection molding, when a composite material is caused to flow into a mold along the predetermined direction from a tip of the bearing, the ribs function as inflow paths of the composite material. Accordingly, the composite material can easily and uniformly flow throughout the entire integrated body of the bearing and the cylinder.
Furthermore, in the course of flowing of the composite material in the radial direction along the ribs, each fiber contained in the composite material extends along an inflow direction. Since the inflow direction is substantially the same as the inclination direction of the drive shaft, rigidity with respect to the inclination direction of the drive shaft can be improved.
A rotary compressor according to an aspect of the present disclosure further includes a bearing wear-resistant portion (36) disposed between the bearing and the drive shaft and formed of a metal material, wherein the bearing is formed of the composite material, and the bearing wear-resistant portion is disposed at both end portions of the bearing in the predetermined direction.
In the configuration described above, the bearing wear-resistant portion is provided between the bearing and the drive shaft. This improves a limit PV value, and thus the wear of the bearing due to the rotation of the drive shaft can be reduced.
Further, in the configuration described above, the bearing wear-resistant portion is disposed at both end portions of the bearing in the predetermined direction. That is, the bearing wear-resistant portion is not disposed at a central portion of the bearing. Thus, when the drive shaft deforms in the inclination direction, the bearing is more likely to deform in response to the deformation of the drive shaft as compared to a case where the bearing wear-resistant portions are disposed over substantially the entire range of the bearing in the predetermined direction. That is, the bearing wear-resistant portions are unlikely to restrict the deformation of the bearing. Since the bearing deforms in response to the deformation of the drive shaft, even when the drive shaft deforms, a surface pressure acting on the bearing can be reduced, and thus the wear of the bearing can be reduced.
Further, in this case, the volume of the bearing wear-resistant portions is reduced as compared to a case where the bearing wear-resistant portions are disposed over substantially the entire range of the bearing in the predetermined direction, and thus the manufacturing cost of the bearing wear-resistant portions can be reduced.
A rotary compressor according to an aspect of the present disclosure further includes a blade that partitions the cylinder chamber into a suction side of the refrigerant and a discharge side of the refrigerant, in which the cylinder is formed of the composite material and includes a blade groove (44) configured to slidably accommodate the blade, and cylinder wear-resistant portions (45, 46) formed of a metal material are disposed at end portions of the blade groove on the cylinder chamber side.
In the configuration described above, the cylinder wear-resistant portions made of a metal material are disposed at the end portions of the blade groove on the cylinder chamber side. Thus, wear of the cylinder due to the sliding of the blade can be reduced.
In addition, for example, when the cylinder wear-resistant portions are provided only at the end portions of the cylinder groove on the cylinder chamber side, the cylinder is more likely to deform in response to a load from the blade as compared to a case where the cylinder wear-resistant portions are disposed over substantially the entire range of the cylinder groove. That is, the cylinder wear-resistant portions are unlikely to restrict the deformation of the cylinder. Since the cylinder deforms responding to a load from the blade, a surface pressure acting on the cylinder can be reduced, and thus the wear of the cylinder can be reduced. Further, in this case, the volume of the cylinder wear-resistant portions is reduced as compared to a case where the cylinder wear-resistant portions are disposed over substantially the entire range of the blade groove, and thus the manufacturing cost of the cylinder wear-resistant portions can be reduced.
In a rotary compressor according to an aspect of the present disclosure, the cylinder is formed of the composite material, and the cylinder includes a suction port (43) that guides the refrigerant to the cylinder chamber and an excess thickness portion (66) disposed on an outer side of the suction port in the radial direction and protruding further outward in the radial direction than other regions.
The refrigerant at a low temperature before compression is guided to a suction port. Thus, the temperature of a region near the suction portion becomes lower than the temperatures of other regions. Thus, in the cylinder formed of the composite material, a region near the suction portion may deform due to a difference in temperature with other regions. When the cylinder deforms, the refrigerant may leak from the cylinder chamber.
On the other hand, in the configuration described above, the cylinder includes the excess thickness portion disposed on the outer side of the suction portion in the radial direction. Thus, a region near the suction portion can be made less likely to deform. Accordingly, even when the cylinder is formed of the composite material, deformation of the cylinder can be suppressed, and thus the leakage of the refrigerant from the cylinder chamber can be suppressed.

Reference Signs List

1: Rotary compressor
2: Hermetic housing
3: Cover
4: Cover
5: Electric motor
6: Compression mechanism
7: Mounting bracket
8: Discharge pipe
10: Suction pipe
12: Stationary element
13: Rotating element
14: Drive shaft
15: Upper eccentric portion
16: Lower eccentric portion
30: Upper compression mechanism
31: Upper cylinder chamber
32: Upper bearing cylinder portion
33: Upper rotor
34: Upper cylinder main portion
34a: Defining portion
34b: Contact portion
34c: Outer frame portion
35: Upper bearing portion
35a: Cylindrical portion
35b: Rib
35c: Annular portion
36: Metal bushing
36a: Notch portion
36b: Stopper portion
37: Junction portion
37a: First bolt hole
38: Bolt
41: First flow path
42: Second flow path
43: Suction port
44: Blade groove
45: Suction-side wear-resistant portion
45a: Protrusion
45b: Recess
46: Discharge-side wear-resistant portion
46a: Protrusion
46b: Recess
50: Separator plate
52: Second bolt hole
60: Lower compression mechanism
65: Sleeve
66: Excess thickness portion
70: Rotary compressor
71: Compression mechanism
72: Upper bearing
73: Lower bearing
74: Cylinder main body portion
75: Bolt
76: Bolt

Claims

A rotary compressor comprising:
a housing that forms an outer shell;

a drive source;

a compression mechanism accommodated in the housing and configured to compress a refrigerant by using a driving force from the drive source; and

a drive shaft connecting the drive source and the compression mechanism and configured to rotate about a center axis extending in a predetermined direction,

the compression mechanism including

a rotor connected to the drive shaft and accommodated in a cylinder chamber,

a cylinder defining an outer side of the cylinder chamber in a radial direction, and

a bearing rotatably supporting the drive shaft and defining the cylinder chamber in the predetermined direction,

the compression mechanism compressing the refrigerant between the rotor being rotated and the cylinder,

the bearing and/or the cylinder being formed of a composite material made by reinforcing a resin with reinforced fibers.
The rotary compressor according to claim 1, wherein
the bearing and the cylinder are formed of the composite material, and the bearing and the cylinder are integrally formed.
The rotary compressor according to claim 2, wherein
the drive source includes a rotating element fixed to the drive shaft and a stationary element surrounding the rotating element,

the compression mechanism includes a plurality of the cylinder chambers arranged in the predetermined direction and a plurality of the rotors respectively accommodated in the cylinder chambers,

the cylinder chambers adjacent to each other in the predetermined direction are separated by a separator,

the bearing and the cylinder integrally formed are fixed to the separator, and

the separator is formed of a metal material and fixed to the housing.
The rotary compressor according to claim 3, further comprising a suction pipe that guides the refrigerant to the compression mechanism, wherein
the suction pipe is connected to the separator, and

the compression mechanism includes a refrigerant flow path that guides the refrigerant supplied from the suction pipe to the cylinder chamber.
The rotary compressor according to claim 4, wherein
the refrigerant flow path includes a downstream end portion connected to a suction port opening to the cylinder chamber, and

one side of the suction port in the predetermined direction is defined by the bearing and an other side of the suction port in the predetermined direction is defined by the separator.
The rotary compressor according to any one of claims 3 to 5, further comprising a screw member configured to fix the bearing and the cylinder integrally formed and the separator, wherein
the bearing and the cylinder integrally formed include a rib that reinforces the bearing and a junction portion defining a screw hole into which the screw member is inserted, and

the junction portion is connected to the rib.
The rotary compressor according to claim 6, wherein a sleeve formed of a metal material is disposed between an inside surface of the screw hole and the screw member.
The rotary compressor according to claim 6 or 7, wherein the rib is a plate-like member having a constant plate thickness and extends in a radial direction from an outside surface of the bearing having a cylindrical shape.
The rotary compressor according to claim 8, wherein
a plurality of the ribs are provided, and
the plurality of ribs are arranged side by side at predetermined intervals in a circumferential direction of the bearing.
The rotary compressor according to any one of claims 1 to 9, further comprising a bearing wear-resistant portion disposed between the bearing and the drive shaft and formed of a metal material, wherein
the bearing is formed of the composite material, and

the bearing wear-resistant portion is disposed at both end portions of the bearing in the predetermined direction.
The rotary compressor according to any one of claims 1 to 10, further comprising a blade that partitions the cylinder chamber into a suction side of the refrigerant and a discharge side of the refrigerant, wherein
the cylinder is formed of the composite material and includes a blade groove configured to slidably accommodate the blade, and

a cylinder wear-resistant portion formed of a metal material is disposed at end portions of the blade groove on a side of the cylinder chamber.
The rotary compressor according to any one of claims 1 to 11, wherein the cylinder is formed of the composite material, and
the cylinder includes a suction port and an excess thickness portion, the suction port guiding the refrigerant to the cylinder chamber, the excess thickness portion disposed on an outer side of the suction port in the radial direction and protruding further outward in the radial direction than other regions.