CN113474559A

CN113474559A - Rotary piston compressor and refrigeration cycle device

Info

Publication number: CN113474559A
Application number: CN201980086932.3A
Authority: CN
Inventors: 和泉晓和; 井柳友宏
Original assignee: Mitsubishi Electric Corp
Current assignee: Mitsubishi Electric Corp
Priority date: 2019-02-20
Filing date: 2019-02-20
Publication date: 2021-10-01
Anticipated expiration: 2039-02-20
Also published as: JP7191194B2; CN113474559B; JPWO2020170361A1; WO2020170361A1

Abstract

A rotary piston compressor includes a compression mechanism portion in a sealed container, the compression mechanism portion having a cylinder block, an upper bearing and a lower bearing, and being provided with a suction connection path and a suction path, wherein a step protruding toward a compression chamber side and receiving a refrigerant is formed in a middle of the suction path of the cylinder block on a side opposite to a connection side of the suction connection path, a protrusion is formed between the suction path of the cylinder block and a circumferential direction of a vane groove, a1 st gap is formed between an upper end portion of the protrusion and the upper bearing, a2 nd gap is formed between a lower end portion of the protrusion and the lower bearing, and the protrusion has flexibility to elastically deflect in a pressing direction of a compression load when the compression load is applied to the vane by the refrigerant in the compression chamber.

Description

Rotary piston compressor and refrigeration cycle device

Technical Field

The present invention relates to a rotary piston compressor and a refrigeration cycle device having a compression mechanism in a sealed container.

Background

As a conventional rotary piston compressor, there is a compressor described in patent document 1. In the technique of patent document 1, the crankshaft has an eccentric portion. The cylinder is provided on the outer peripheral side of the eccentric portion and is formed in a cylindrical shape. The piston rotates following the eccentric portion, and a compression chamber is formed between the eccentric portion and the cylinder. The upper bearing and the lower bearing respectively seal and block two end faces of the cylinder body. Further, the cylinder is formed with an intake passage extending from the outer peripheral surface to the cylinder chamber.

Here, since the refrigerant pressure of the carbon dioxide refrigerant is higher than that of the freon refrigerant, the load on the bearing is large, the differential pressure is also large, and the adverse effect due to the refrigerant leakage is large. Therefore, in order to reduce the bearing load and improve the compressor efficiency, it is effective to make the cylinder thinner when using a carbon dioxide refrigerant, as compared with a compressor using a refrigerant other than a carbon dioxide refrigerant.

If the cylinder is thin, a sufficient cross-sectional area of the passage cannot be secured when the suction passage is formed in the cylinder. Therefore, a pressure loss of the suction refrigerant increases, resulting in a decrease in efficiency.

In view of this, a suction connection passage connected to the suction passage is formed in each of the upper and lower bearings that close the cylinder block, and a passage cross-sectional area is sufficiently secured, thereby reducing a pressure loss of the suction refrigerant (see, for example, patent document 2).

Patent document 1: japanese patent laid-open publication No. 2006-200504

Patent document 2: japanese laid-open patent publication No. 2001-82369

In a conventional hermetic compressor of this type, a vane separates a high pressure chamber from a low pressure chamber during driving. Therefore, the high-pressure refrigerant gas in the high-pressure chamber presses the vane against the vane groove. This causes uneven contact (uneven contact) between the inner end of the cylinder in the radial direction in the vane groove and the side surface of the vane, which increases the local surface pressure and increases the wear.

In the conventional rotary compressor having a suction connection passage in the upper bearing or the lower bearing, the cross-sectional area of the refrigerant flow passage is narrowed when the refrigerant flows into the compression chamber formed by the cylinder and the piston from the suction connection passage provided in the bearing. Therefore, even if the suction connection passage having the opening diameter of the same degree as that of the conventional one is formed, the pressure loss of the sucked refrigerant cannot be reduced in practice.

Disclosure of Invention

The present invention has been made to solve the above problems, and an object of the present invention is to provide a rotary piston compressor and a refrigeration cycle apparatus in which uneven contact between a vane and a cylinder is prevented when the compressor is driven, the lubricity of the vane is improved, a cross-sectional area of a refrigerant flow path can be sufficiently ensured when a refrigerant is guided from an intake pipe to a compression chamber, and a pressure loss of an inflow refrigerant can be reduced.

A rotary piston compressor according to the present invention includes a compression mechanism portion in a sealed container, the compression mechanism portion including a cylinder body having a compression chamber formed therein and a vane groove in which vanes are arranged, an upper bearing covering an upper end surface of the cylinder body, and a lower bearing covering a lower end surface of the cylinder body, and being provided with a suction connection passage through which a refrigerant is sucked through a suction hole formed in either the upper bearing or the lower bearing, and a suction passage through which the refrigerant is circulated from the suction connection passage to the compression chamber on a radially outer side of the cylinder body than the compression chamber, wherein a step protruding toward the compression chamber side and receiving the refrigerant is formed on a side opposite to a connection side of the suction connection passage in a middle of the suction passage of the cylinder body, and a protrusion protruding toward the compression chamber side is formed between the suction passage of the cylinder body and a circumferential direction of the vane groove And a portion having a1 st gap formed between an upper end portion of the projection and the upper bearing and a2 nd gap formed between a lower end portion of the projection and the lower bearing, the projection having flexibility to elastically deflect in a pressing direction of a compression load when the compression load is applied to the vane by a refrigerant in the compression chamber.

The refrigeration cycle apparatus according to the present invention includes the above-described rotary piston compressor.

According to the rotary piston compressor and the refrigeration cycle apparatus of the present invention, the projection has flexibility to elastically deflect in the pressing direction of the compression load when the compression load is applied to the vane by the refrigerant in the compression chamber. This prevents uneven contact between the vane and the cylinder when the compressor is driven. A step that protrudes toward the compression chamber side and receives the refrigerant is formed in the suction path on the opposite side to the connection side of the suction connection path. Thus, in the suction path, a sufficient cross-sectional area of the refrigerant flow path can be ensured when the refrigerant is guided from the suction pipe to the compression chamber. Therefore, the uneven contact between the vane and the cylinder body can be prevented when the compressor is driven, the lubricity of the vane can be improved, the cross-sectional area of the refrigerant flow path can be sufficiently ensured when the refrigerant is guided from the suction pipe to the compression chamber, and the pressure loss of the inflow refrigerant can be reduced.

Drawings

Fig. 1 is an explanatory view showing a rotary piston compressor according to embodiment 1 of the present invention in a vertical cross section.

Fig. 2 is an explanatory diagram showing a compression mechanism according to embodiment 1 of the present invention in a cross-sectional view.

Fig. 3 is an explanatory diagram showing a suction connection passage and a suction path according to embodiment 1 of the present invention in a vertical cross section taken along line a-a in fig. 2.

Fig. 4 is an explanatory view showing the protrusion according to embodiment 1 of the present invention in a vertical cross section taken along line B-B in fig. 2.

Fig. 5 is an explanatory diagram illustrating a cutting process of the suction path according to embodiment 1 of the present invention.

Fig. 6 is a flowchart showing a cutting process of the suction path according to embodiment 1 of the present invention.

Fig. 7 is an explanatory diagram showing a suction connection path and a suction path in a vertical cross section in comparative example 1.

Fig. 8 is an explanatory diagram showing a suction connection passage and a suction path in a vertical cross section in comparative example 2.

Fig. 9 is a refrigerant circuit diagram showing a refrigeration cycle apparatus to which a rotary piston compressor according to embodiment 2 of the present invention is applied.

Detailed Description

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings, the same or corresponding components are denoted by the same reference numerals and are common throughout the specification. In the drawings of the cross-sectional view, hatching is appropriately omitted in view of visibility. The form of the building element shown throughout the specification is merely an example, and is not limited to these descriptions.

Embodiment 1.

Fig. 1 is an explanatory diagram showing a compressor 100, which is a rotary piston compressor according to embodiment 1 of the present invention, in a vertical cross section. Fig. 2 is an explanatory diagram showing a compression member 5 as a compression mechanism according to embodiment 1 of the present invention in a cross-sectional view. As shown in fig. 1, the compressor 100 is used, for example, by being connected to an evaporator 104 of a refrigeration cycle apparatus 101 shown in fig. 9 through a suction pipe 7a and connected to a condenser 102 of the refrigeration cycle apparatus 101 through a discharge pipe 7 b.

The hermetic container 2 constituting the external appearance of the compressor 100 is composed of a substantially cylindrical body portion 21, a substantially hemispherical upper lid portion 22, and a lower lid portion 23. An upper lid portion 22 is welded to an upper portion of the main body portion 21, and a lower lid portion 23 is welded to a lower portion of the main body portion 21. The closed casing 2 is provided on the base 3. The lower cover 23 is fixed to the pedestal 3. The compressor 100 is fixed to the installation site by bolts or the like in a normal installation state.

Inside the closed casing 2, an electric element 4 constituting a driving unit and a compression element 5 constituting a compression mechanism unit are housed.

The electric element 4 is composed of a stator 41 fixed to the inner peripheral surface of the body portion 21 of the sealed container 2 and a rotor 42 disposed with a slight gap inside the stator 41. The stator 41 and the body 21 are fixed by spot welding, shrink fitting, or the like. The electric component 4 is connected to a terminal 6a attached to the center of the upper lid 22 via a lead wire 6 b. Power is supplied from the terminal 6a to the electric component 4 via the wire 6 b.

The compression element 5 is composed of a crankshaft 51, a cylinder 52, an upper bearing 53, a lower bearing 54, a roller 55, and a vane 56. The body 21 and the upper bearing 53 are fixed by spot welding. The crankshaft 51 has a roller 55 on an outer peripheral portion of an eccentric portion 51a eccentric in one direction, and the crankshaft 51 is inserted and fixed to a central portion of the rotor 42 of the electric component 4. The cylinder block 52 is a cylindrical member and has a compression chamber 52a formed therein concentrically with the crankshaft 51. The cylinder 52 is formed with vane grooves 52e in which the vanes 56 are disposed. The upper bearing 53 and the lower bearing 54 support the crankshaft 51. An upper bearing 53 is disposed at an end portion of an upper portion of the cylinder 52 to cover an upper end surface of the cylinder 52. A lower bearing 54 is disposed at an end portion of a lower portion of the cylinder block 52 to cover a lower end surface of the cylinder block 52. The roller 55 is mounted as an eccentric portion 51a of the crankshaft 51 inside the cylinder 52. The vane 56 is inserted into a vane groove 52e provided in the cylinder 52, and partitions the compression chamber 52a into a low-pressure chamber 52g and a high-pressure chamber 52 h.

The main body 21 is provided with a through hole. The through hole is connected to a suction pipe 7 a. The front end of the suction pipe 7a is inserted into a suction hole 53a provided in the upper bearing 53. The suction hole 53a is connected to a suction connection passage (suction passage)53b formed parallel to the crankshaft 51 from the lower end surface of the upper bearing 53. The suction connection passage 53b sucks the refrigerant gas through a suction hole 53a formed in the upper bearing 53.

The suction connection path 53b of the upper bearing 53 is provided on the outer peripheral side of the compression chamber 52a of the cylinder 52, and is connected to a suction path 52b having a step (stepped part)52 c. The suction path 52b causes refrigerant to flow from the suction connection path 53b to the compression chamber 52a on the radially outer side of the compression chamber 52a of the cylinder 52.

The cylinder 52 is formed with vane grooves 52e extending in the radial direction from between the suction path 52b and the discharge port 52 d. The vane grooves 52e extend radially outward of the cylinder 52 from the compression chamber 52a, and penetrate both the upper and lower surfaces of the cylinder 52. The outer peripheral side of the vane groove 52e is connected to an outer peripheral side hole 52f that penetrates both the upper and lower surfaces in the same manner. A vane 56 is inserted into the vane groove 52e to separate the compression chamber 52a into a low pressure chamber 52g on a low pressure side and a high pressure chamber 52h on a high pressure side. The radially inner tip of the vane 56 abuts against the outer peripheral surface of the roller 55 by a spring 57 accommodated in a hole 52f which is a radially outer back portion. A discharge port 52d is provided near the vane 56 on the high pressure chamber 52h side. The outlet 52d communicates with an opening that opens into the internal space of the sealed container 2.

In the cylinder 52, an elastically deformable projection 52j is formed between the suction path 52b having the width a1 and the vane groove 52 e. The projection 52j projects toward the compression chamber 52a between the suction path 52b of the cylinder 52 and the vane groove 52e in the circumferential direction. The projection 52j has flexibility to elastically deflect in the pressing direction by a compression load when the compression load is applied to the vane 56 by the refrigerant gas in the compression chamber 52 a.

Fig. 3 is an explanatory diagram showing a suction connection passage 53b and a suction path 52b according to embodiment 1 of the present invention in a vertical cross section taken along line a-a in fig. 2. As shown in fig. 3, a step 52c that protrudes toward the compression chamber 52a side and receives the refrigerant gas is formed in the middle of the suction path 52b of the cylinder 52 on the side opposite to the side where the suction connection path 53b is connected. The step 52c is a step-like step portion of 1 step. The step 52c is a flat plate shape formed by bending perpendicularly from the vertical wall surface of the space portion where the suction path 52b is formed and forming the surface of the suction connection path 53b on the connection side flat. When the step 52c is formed, the tool 10 shown with reference to fig. 5 performs a cutting process in the vertical direction from the connection side of the suction connection path 53b to form a space portion hollowed out in the vertical direction to form the suction path 52 b. Then, the tool 10 performs a cutting process from the position where the space portion of the suction passage 52b is formed toward the compression chamber 52a, thereby enlarging the space portion where the suction passage 52b is formed and forming an upward flat surface of the step 52 c. Then, the tool 10 cuts the suction connecting passage 53b on the side opposite to the side connected thereto, so that the space portion in which the suction passage 52b is formed penetrates in the vertical direction, and the tip portion 52c1 on the compression chamber 52a side of the step 52c is formed. Thereby, the step 52c of 1 layer in a flat plate shape is formed. The step 52c has a width a2 on the outer circumferential side lower surface in the suction path 52b of the cylinder 52, and protrudes to the compression chamber 52a side by a length a 3. The space portion on the inner peripheral side of the step 52c, in which the suction path 52b is formed, penetrates both the upper and lower surfaces, and communicates with the compression chamber 52 a.

Fig. 4 is an explanatory diagram showing the protrusion 52j according to embodiment 1 of the present invention in a vertical cross section taken along line B-B in fig. 2. As shown in fig. 4, a1 st gap 60a is formed between the upper end of the projection 52j and the upper bearing 53. A2 nd gap 60b is formed between the lower end of the projection 52j and the lower bearing 54. The 1 st gap 60a and the 2 nd gap 60b are secured so as not to contact the upper bearing 53 and the lower bearing 54 attached to the cylinder block 52, respectively, at both upper and lower end surfaces of the protrusion 52 j. The 1 st gap 60a and the 2 nd gap 60b are set to have a gap depth, i.e., a gap formed, of 0.1 to 0.15mm, for example.

< cutting step 52c >

Fig. 5 is an explanatory diagram illustrating a cutting process of the suction passage 52b according to embodiment 1 of the present invention. Fig. 6 is a flowchart showing a cutting process of the suction passage 52b according to embodiment 1 of the present invention.

As shown in fig. 5, the step 52c is machined by the tool 10 such as an end mill through successive cutting steps. The tool 10 is controlled to perform cutting by communicating with a control unit 11 via a wired or wireless communication line 12. The control unit 11 is hardware that executes software processing called cutting.

As shown in fig. 5 and 6, in step S1, the control unit 11 performs a cutting process from the connection side of the suction connection passage 53b downward by the tool 10 to form a space portion serving as the suction path 52b up to the surface of the step 52c hollowed out in the vertical direction.

In step S2, the control unit 11 performs a cutting process with the tool 10 from the position where the space portion of the suction path 52b up to the surface of the step 52c is formed toward the center of the cylinder 52 on the compression chamber 52a side, thereby expanding the space portion of the suction path 52b toward the compression chamber 52a side and forming a flat surface of the step 52 c.

In step S3, the controller 11 cuts the tool 10 to the side opposite to the side connected to the suction connecting passage 53b, so that the space portion that becomes the suction passage 52b penetrates in the vertical direction and the radially inner end portion 52c1 of the step 52c is formed. Thus, the step 52c is formed in a flat plate shape having 1 layer.

< action of compressor 100 >

When electric power is supplied through the terminal 6a, the crankshaft 51 fixed to the rotor 42 rotates about the crankshaft 51. Thereby, the refrigerant gas is sucked from the refrigeration cycle apparatus 101 into the compression chamber 52a through the suction pipe 7a and the suction path 52b, and is compressed in the compression chamber 52a by the eccentric movement of the roller 55. The compressed high-pressure refrigerant gas is released into the closed casing 2, and the inside of the closed casing 2 is brought into a high-pressure state. The high-pressure refrigerant gas in the closed casing 2 is discharged to the refrigeration cycle apparatus 101 through the discharge pipe 7 b. Crankshaft 51 is located on the center line of main body 21.

During compression, the vane 56 that protrudes into the compression chamber 52a and separates the low-pressure chamber 52g from the high-pressure chamber 52h while abutting against the roller 55 is pressed in the direction of the vane groove 52e by the compression load of the high-pressure refrigerant. That is, the compression chamber 52a side of the vane 56 is pressed in the pressing direction of the compression load by the compression load. At this time, the projection 52j is elastically deflected in the pressing direction by the pressing of the vane 56. This prevents uneven contact between the vane 56 and the vane groove 52e, prevents wear due to uneven contact, and facilitates movement of the vane 56.

When the projection 52j is deflected, the projection 52j does not contact the upper bearing 53 and the lower bearing 54 attached to the cylinder 52 due to the 1 st gap 60a and the 2 nd gap 60b formed on the upper and lower end surfaces of the projection 52j, respectively. Thus, since the projection 52j is not in sliding contact with the upper bearing 53 and the lower bearing 54, respectively, abrasion of the projection 52j, the upper bearing 53, and the lower bearing 54 can be prevented, and an increase in mechanical loss can be prevented.

When a compressive load is applied, the step 52c provided in the suction path 52b supports the root of the projection 52 j. This can increase the strength of the projection 52j against the compressive load, and can suppress deformation or breakage due to insufficient strength of the projection 52 j. In particular, when the vertical height a4 of the cylinder 52 is made thin in order to reduce loss due to refrigerant leakage, the strength of the projection 52j is reduced. Therefore, this effect is more effective in thinning the cylinder block 52. However, if the width a1, the width a2, and the projection length a3 of the step 52c are increased, the effect of preventing abrasion due to the deflection of the projection 52j is reduced, and the refrigerant flow path is narrowed, so that the pressure loss of the refrigerant is increased.

In order to prevent an increase in the pressure loss of the refrigerant, it is necessary to provide no position in the refrigerant flow path from the suction port 53a, where the cross-sectional area is narrower than the suction port 53 a. That is, the width a1, the width a2, and the projection length a3 of the step 52c need to be set so that the width a6 where the spatial distance is the smallest and the diameter a5 of the suction hole 53a are in a relationship of a6 > a5 in the suction path 52 b.

By providing the step 52c in the suction path 52b of the cylinder 52, the increase in the extent of the refrigerant gas path curvature is stepwise, and the increase in the extent of 1-time curvature can be reduced. Therefore, it is difficult to form a vortex which becomes turbulent flow of the refrigerant gas. Therefore, the pressure loss of the inflow refrigerant can be reduced. In order to prevent the formation of a swirl of the refrigerant gas and reduce the pressure loss of the refrigerant gas, it is effective if the vertical height a4 of the cylinder 52 and the vertical height a2 of the step 52c are in a relationship of a4/a2 of 2 to 5.

The compressor 100 is particularly effective when compression is performed at a high differential pressure, such as when the refrigerant is carbon dioxide.

< comparative example 1 >

Fig. 7 is an explanatory diagram showing a suction connection passage 53b and a suction path 52b in a vertical cross section in comparative example 1. In comparative example 1 for comparison with embodiment 1 shown in fig. 7, a slope 52c2 having a width a6 that minimizes the spatial distance is formed in the suction path 52b without forming the step 52 c. When the effect of reducing the pressure loss of the refrigerant gas is compared between the compressor 100 of embodiment 1 and the compressor 100 of comparative example 1, the refrigerant gas of the compressor 100 of embodiment 1 exhibits the effect of reducing the pressure loss by 4.6% with respect to the compressor 100 of comparative example 1. This makes it clear the superiority of the compressor 100 according to embodiment 1.

< comparative example 2 >

Fig. 8 is an explanatory diagram showing a suction connection passage 53b and a suction path 52b in a vertical cross section in comparative example 2. In comparative example 2 for comparison with embodiment 1 shown in fig. 8, step 52c is not formed. In the case of comparative example 2, although the effect of reducing the pressure loss of the refrigerant gas in the suction path 52b is superior, the amount of deflection of the projection 52j is increased and the mechanical loss of the projection 52j is likely to occur because the step 52c supporting the projection 52j is not provided. Further, since the projection 52j is excessively bent, the vane 56 is inclined with respect to the vane groove 52e and is less likely to move in the radial direction, and the lubricity of the vane 56 is deteriorated. This makes it clear the superiority of the compressor 100 according to embodiment 1.

< Effect of embodiment 1 >

According to embodiment 1, a compressor 100 as a rotary piston compressor includes a compression element 5 as a compression mechanism and an electric element 4 as a driving unit in a sealed container 2. The compression member 5 has a cylinder 52 in which a compression chamber 52a is formed and a vane groove 52e in which the vane 56 is disposed is formed. The compression member 5 has an upper bearing 53 covering the upper end surface of the cylinder block 52 and a lower bearing 54 covering the lower end surface of the cylinder block 52. A suction connection path 53b is provided through which refrigerant is sucked through a suction hole 53a formed in the upper bearing 53 or the lower bearing 54. A suction passage 52b through which the refrigerant flows from the suction connection passage 53b to the compression chamber 52a is provided radially outward of the cylinder block 52 from the compression chamber 52 a. A step 52c that projects toward the compression chamber 52a side and receives the refrigerant is formed in the middle of the suction path 52b of the cylinder 52 on the side opposite to the side where the suction connection path 53b is connected. A projection 52j projecting toward the compression chamber 52a is formed between the suction path 52b of the cylinder 52 and the vane groove 52e in the circumferential direction. A1 st gap 60a is formed between the upper end of the projection 52j and the upper bearing 53. A2 nd gap 60b is formed between the lower end of the projection 52j and the lower bearing 54. The projection 52j has flexibility to elastically deflect in the pressing direction of the compression load when the compression load is applied to the vane 56 by the refrigerant in the compression chamber 52 a.

According to this configuration, when a compression load is applied to the vane 56 by the refrigerant in the compression chamber 52a, the flexible projection 52j elastically flexes in the pressing direction of the compression load. This prevents uneven contact between the vane 56 and the cylinder block 52 during driving of the compressor 100, reduces the surface pressure of the contact portion, prevents wear of the contact portion, and improves the lubricity of the vane 56. Further, since the upper bearing 53 and the lower bearing 54 are separated from the cylinder block 52 by the 1 st gap 60a and the 2 nd gap 60b formed above and below the projection 52j, even if the projection 52j is bent, the projection 52j and the upper bearing 53 and the lower bearing 54 attached to the upper and lower sides of the cylinder block 52 are not worn. By providing the suction passage 52b radially outside the compression chamber 52a of the cylinder block 52, the cross-sectional area of the refrigerant flow passage in the suction passage 52b can be set to be equal to or larger than the cross-sectional area of the suction hole 53a, and the refrigerant gas can reach the compression chamber 52a without narrowing the cross-sectional area in the flow direction of the refrigerant gas flowing into the suction hole 53 a. A step 52c that protrudes toward the compression chamber 52a side and receives the refrigerant is formed in the suction path 52b on the opposite side of the connection side of the suction connection path 53 b. Accordingly, in the suction path 52b, the cross-sectional area of the refrigerant flow path can be sufficiently ensured when the refrigerant is guided from the suction pipe 7a to the compression chamber 52a, and the pressure loss of the refrigerant flowing in can be reduced. Further, the step 52c can reduce the width of the flow of the refrigerant gas in the suction path 52b, and thus, the swirl which becomes turbulent flow of the refrigerant gas is less likely to be formed, and the pressure loss of the refrigerant flowing in can be reduced. Therefore, uneven contact between the vane 56 and the cylinder block 52 can be prevented during driving of the compressor 100, the lubricity of the vane 56 can be improved, the cross-sectional area of the refrigerant flow path can be sufficiently ensured when the refrigerant is guided from the suction pipe 7a to the compression chamber 52a, and the pressure loss of the refrigerant flowing in can be reduced. Further, by providing the step 52c in the suction path 52b of the cylinder 52, the strength of the projection 52j formed between the suction path 52b of the cylinder 52 and the vane groove 52e can be increased. Accordingly, when the cylinder 52 is thinned and the vane 56 is pressed toward the vane groove 52e by the high-pressure refrigerant, the projection 52j can be prevented from being deformed or damaged due to insufficient strength.

According to embodiment 1, the suction connection passage 53b is formed in the upper bearing 53.

With this configuration, when the refrigerant is guided from the suction pipe 7a to the compression chamber 52a, the cross-sectional area of the refrigerant flow path can be sufficiently ensured in the direction of gravity, and the pressure loss of the refrigerant flowing in can be further reduced.

According to embodiment 1, the step 52c is a step portion of 1 layer.

According to this configuration, the pressure loss of the inflow refrigerant can be reduced by 4.6% as compared with comparative example 1 in which the slope 52c2 of the step 52c is not provided.

According to embodiment 1, the step 52c is a flat plate shape in which the surface of the suction connecting passage 53b on the connecting side is formed flat.

According to this configuration, a sufficient cross-sectional area of the refrigerant flow path can be ensured without generating a vortex such as turbulent flow when the refrigerant is guided from the suction pipe 7a to the compression chamber 52a, and the pressure loss of the refrigerant flowing in can be further reduced.

According to embodiment 1, the step 52c is a flat plate shape as follows: a space portion is formed by cutting the tool 10 from the connection side of the suction connection passage 53b downward to the surface of the step 52c hollowed out in the vertical direction, the tool 10 is cut from this position toward the compression chamber 52a side to expand the space portion toward the compression chamber 52a side and form a flat surface of the step 52c, and then the tool 10 is cut to the opposite side of the connection side of the suction connection passage 53b to penetrate the space portion in the vertical direction and form the tip portion 52c1 of the step 52 c.

With this configuration, the step 52c can be formed by simple continuous cutting with the tool 10.

According to embodiment 1, the carbon dioxide refrigerant is compressed.

According to this configuration, even if a carbon dioxide refrigerant having a refrigerant pressure higher than that of the freon refrigerant is used, the cylinder 52 has a small thickness, and the bearing load can be reduced and the compressor efficiency can be improved.

According to embodiment 1, the relationship of 2. ltoreq. a4/a 2. ltoreq.5 is satisfied where a4 denotes the height of the cylinder 52 in the vertical direction and a2 denotes the height of the step 52 c.

According to this configuration, by forming the step 52c, formation of a vortex which becomes turbulent flow of the refrigerant gas can be prevented, and the pressure loss of the inflow refrigerant can be reduced.

Embodiment 2.

< refrigeration cycle apparatus 101 >

Fig. 9 is a refrigerant circuit diagram showing a refrigeration cycle apparatus 101 to which a compressor 100 as a rotary piston compressor according to embodiment 2 of the present invention is applied.

As shown in fig. 9, the refrigeration cycle apparatus 101 includes: a compressor 100, a condenser 102, an expansion valve 103, and an evaporator 104. The compressor 100, the condenser 102, the expansion valve 103, and the evaporator 104 are connected by refrigerant pipes to form a refrigeration cycle. The refrigerant flowing out of the evaporator 104 is sucked into the compressor 100 and becomes high-temperature and high-pressure. The high-temperature and high-pressure refrigerant is condensed in the condenser 102 to become liquid. The refrigerant that has become liquid is decompressed and expanded in the expansion valve 103, and becomes a low-temperature low-pressure two-phase gas-liquid, and the two-phase gas-liquid refrigerant is heat-exchanged in the evaporator 104.

The compressor 100 according to embodiment 1 can be applied to such a refrigeration cycle apparatus 101. The refrigeration cycle apparatus 101 may be, for example, an air conditioner, a refrigeration apparatus, or a hot water supply device.

< Effect of embodiment 2 >

According to embodiment 2, the refrigeration cycle apparatus 101 includes the compressor 100 as the rotary piston compressor described above.

According to this configuration, since the refrigeration cycle apparatus 101 includes the compressor 100, uneven contact between the vane 56 and the cylinder 52 can be prevented when the compressor 100 is driven, the lubricity of the vane 56 can be improved, the cross-sectional area of the refrigerant flow path can be sufficiently ensured when the refrigerant is guided from the suction pipe 7a to the compression chamber 52a, and the pressure loss of the refrigerant flowing in can be reduced.

[ description of reference numerals ]

2 … sealing the container; 3 … stand-off; 4 … electric component; 5 … compression member; 6a … terminal; 6b … wire; 7a … suction tube; 7b … discharge pipe; 10 … tool; 11 … a control unit; 12 … communication line; 21 … a body portion; 22 … upper cover part; 23 … lower cover part; 41 … stator; 42 … rotor; 51 … crankshaft; 51a … eccentric portion; 52 … cylinder body; 52a … compression chamber; 52b … suction path; 52c … steps; 52c1 … front end; 52c2 … ramp; 52d … discharge port; 52e … vane slot; 52f … pore; 52g … low pressure chamber; 52h … high pressure chamber; 52j … protrusions; 53 … upper bearing; 53a … suction port; 53b … suction connection path; 54 … lower bearing; a roll 55 …; 56 … leaf blade; a 57 … spring; 60a … gap No. 1; 60b … gap No. 2; 100 … compressor; 101 … refrigeration cycle device; 102 … condenser; 103 … expansion valve; 104 … evaporator.

Claims

1. A rotary piston compressor including a compression mechanism in a sealed container, characterized in that,

the compression mechanism unit includes a cylinder block having a compression chamber formed therein and a vane groove in which vanes are disposed, an upper bearing covering an upper end surface of the cylinder block, and a lower bearing covering a lower end surface of the cylinder block,

the compression mechanism portion is provided with a suction connection passage through which a refrigerant is sucked through a suction hole formed in either the upper bearing or the lower bearing, and a suction path through which the refrigerant flows from the suction connection passage to the compression chamber on a radially outer side of the compression chamber in the cylinder block,

a step protruding toward the compression chamber side and receiving the refrigerant is formed in a middle of the suction path of the cylinder on a side opposite to a connection side of the suction connection path,

a projection portion that projects toward the compression chamber side is formed between the suction path of the cylinder block and a circumferential direction of the vane groove,

a1 st gap is formed between an upper end portion of the protrusion portion and the upper bearing,

a2 nd gap is formed between the lower end of the protrusion and the lower bearing,

the projection has flexibility to elastically deflect in a pressing direction of a compression load when the compression load is applied to the vane by a refrigerant in the compression chamber.

2. A rotary piston compressor according to claim 1,

the suction connection path is formed in the upper bearing.

3. A rotary piston compressor according to claim 1 or 2,

the steps are 1-level steps.

4. A rotary piston compressor according to any one of claims 1-3,

the step is a flat plate shape having a flat surface on the connection side of the suction connection path.

5. A rotary piston compressor according to claim 4,

the steps are flat as follows: the suction connection passage is formed by cutting the suction connection passage from the connection side thereof in the vertical direction with a tool to form a space hollowed in the vertical direction, the tool is used to cut the suction connection passage from the position to the compression chamber side to expand the space and form a flat surface of the step, and the tool is used to cut the suction connection passage from the opposite side to the connection side thereof to penetrate the space in the vertical direction and form a tip portion of the step.

6. A rotary piston compressor according to any one of claims 1-5,

the carbon dioxide refrigerant is compressed.

7. A rotary piston compressor according to any one of claims 1-6,

when the height of the cylinder in the vertical direction is a4 and the height of the step is a2, the relationship of 2 ≦ a4/a2 ≦ 5 is satisfied.

8. A refrigeration cycle apparatus, characterized in that,

a rotary piston compressor according to any one of claims 1 to 7.