WO2021198732A1

WO2021198732A1 - Scroll compressor

Info

Publication number: WO2021198732A1
Application number: PCT/IB2020/053087
Authority: WO
Inventors: Supot SIWAPORNPHAISARN; Chirawat CHANDANG
Original assignee: Siam Compressor Industry Co., Ltd.
Priority date: 2020-04-01
Filing date: 2020-04-01
Publication date: 2021-10-07

Abstract

The present invention discloses a scroll compressor 100 which includes a sealed container 10, a motor element 20 housed in the sealed container 10, a scroll compression element 30 driven by a rotating shaft portion 16 of the motor element 20, and an injection pipe 60 mounted penetratingly a side face of the sealed container 10. The scroll compression element 30 includes a fixed scroll 40 including a first scroll body 40b and an orbiting scroll 50. The injection pipe 60 is arranged inclinedly with respect to the radial direction of the sealed container 10 so that an opening of the injection pipe 60 on the inner side of the sealed container 10 faces to a first scroll end portion 42 of an outermost tooth 40b1 of the first scroll body 40b.

Description

TITLE OF THE INVENTION SCROLL COMPRESSOR

FIELD OF INVENTION

The present invention relates to a scroll compressor.

BACKGROUND OF THE INVENTION

It is known that a scroll compressor which includes a sealed container, an injection pipe in which gas refrigerant sucked from outside flows into the scroll compressor, and a scroll compression element including a fixed scroll including a first scroll body and an orbiting scroll including a second scroll body configured to be engaged with the first scroll body to form a compression chamber between the first scroll body and the second scroll body, as disclosed in Japanese laid-open publication No. JP2011-163256A (PTL1).

In the prior art, the injection pipe is mounted penetratingly a side face of the sealed container so to extend in the radial direction of the sealed container. Moreover, the injection is formed to change the flow of gas refrigerant in the vicinity of an outlet opening of the injection pipe so as to direct gas refrigerant to the area between the first scroll body and the second scroll body.

However, since the injection is bent so as to change the flow of gas refrigerant in the vicinity of an outlet opening of the injection pipe, the pressure loss of the gas refrigerant is generated at the vicinity of the outlet opening of the injection pipe

Therefore, the development of the scroll compressor which is capable to reduce the pressure loss of gas refrigerant in the sucking step sucking gas refrigerant into the scroll compression element, is required.

CITATION LIST Patent Literature

PTL 1: Japanese laid-open publication No.: JP2011-163256A

SUMMARY OF THE INVENTION

The objective of the present invention is to provide a scroll compressor which is capable to reduce the pressure loss of gas refrigerant in the sucking step sucking gas refrigerant into the scroll compression element. In order to achieve the above objective, an embodiment of the present invention provides a scroll compressor comprising: a sealed container; a motor element housed in the sealed container; a scroll compression element housed in the sealed container and configured to be driven by a rotating shaft portion of the motor element; and an injection pipe mounted penetratingly a side face of the sealed container, in which gas refrigerant sucked from outside flows into the scroll compression, wherein the scroll compression element including a fixed scroll including a first scroll body and an orbiting scroll including a second scroll body configured to be engaged with the first scroll body to form a compression chamber between the first scroll body and the second scroll body, the orbiting scroll being configured to orbit opposed to the fixed scroll, and wherein the injection pipe is arranged inclinedly with respect to the radial direction of the sealed container so that an opening of the injection pipe on the inner side of the sealed container faces to a first scroll end portion of an outermost tooth of the first scroll body.

According to the embodiment of the present invention, firstly, gas refrigerant is sucked from outside flows into the scroll compression element in the sucking step sucking gas refrigerant into the scroll compression element.

Since the injection pipe is arranged inclinedly with respect to the radial direction of the sealed container, it is not necessary to bend the injection pipe so as to direct gas refrigerant to the scroll compression element. As such, it is possible to reduce the pressure loss of the gas refrigerant in the inside of the injection pipe.

Moreover, since the opening of the injection pipe on the inner side of the sealed container faces to a first scroll end portion of an outermost tooth of the first scroll body, it is possible to reduce the occurrence of the pressure loss of the gas refrigerant between the opening of the injection pipe and the scroll compression element.

As a result, it is possible to reduce the pressure loss of gas refrigerant in the sucking step sucking gas refrigerant into the scroll compression element, and furthermore to increase the performance of the scroll compressor.

BRIEF DESCRIPTION OF DRAWINGS

The principle of the present invention and its advantages will become apparent in the following description taking in consideration with the accompanying drawings in which:

FIG.1 is a longitudinal section view illustrating a schematic configuration of a scroll compressor 100 according to the embodiment of this invention;

FIG.2 is an end view taken along line II-II of FIG.1 ; FIG.3 is an explanatory view of the injection pipe 60 and the scroll compression element 30 without the orbiting scroll 50;

FIG.4 is an enlarged view of an area A of FIG.3; and

FIG.5(a) to FIG.5(d) are diagrams illustrating relative oscillatory motion of a first scroll body 40b and a second scroll body 50b for one cycle.

DETAILED DESCTIPTION OF EMBODIMENTS OF THE INVENTION

Hereinafter, the scroll compressor 100 according to embodiments of the invention will be described with reference to the drawings and the like.

FIG.1 is a longitudinal section view illustrating a schematic configuration of a scroll compressor 100 according to the embodiment. The scroll compressor 100 is a fluid machine configured to compress and discharge a fluid (e.g., gas refrigerant), and can be a component of a refrigeration cycle apparatus, for example, in a refrigerator, a freezer, an automatic vending machine, an air-conditioning apparatus, a refrigeration unit, and a water heater. The scroll compressor 100 according to the embodiment is a vertically-mounted shell compressor.

As shown in FIG.1, the scroll compressor 100 includes a sealed container 10, an injection pipe 60 mounted penetratingly a side face of the sealed container 10, a discharge pipe 15 discharging the fluid to the outside, a scroll compression element 30 configured to compress a fluid (low-pressure gas refrigerant), and a motor element 20 configured to drive the scroll compression element 30 are housed in a sealed container 10.

The upper portion of the scroll compression element 30 is fixed and supported by a middle shell 12. The scroll compression element 30 is the middle shell 12 of the sealed container 10 through shrink fit or other method. A sub-frame 13 is provided below the motor element 20. The sub-frame 13 is fixed to the inner circumferential surface of the sealed container 10. An oil sump 14 is formed on a bottom of the sealed container 10. A refrigerating machine oil lubricating sliding parts such as bearings is accumulated in the oil sump 14.

The suction pipe configured to suck a fluid (low-pressure gas refrigerant) into the scroll compression element 30 from outside is connected to a side face of the sealed container 10. Details will be described later. The discharge pipe 15 configured to discharge the fluid (high- pressure gas refrigerant) to the outside of the scroll compressor 100 is connected to a side face of the sealed container 10. The scroll compression element 30 is housed in the sealed container 10 and configured to be driven by a rotating shaft portion 16 of the motor element 20. As shown in FIG.2 and FIG.3, the scroll compression element 30 includes a fixed scroll 40 and an orbiting scroll 50.

The fixed scroll 40 is fixed to the middle shell 12 at a lower end portion of the fixed scroll 40. The fixed scroll 40 includes a base plate 40a and a first scroll body 40b having an involute curve shape and erected on one surface of the base plate 40a. A discharge port 44 configured to discharge a compressed fluid is formed in a central part of the fixed scroll 40.

The orbiting scroll 50 is configured to orbit opposed to the fixed scroll 40 without rotating, by a non-illustrated Oldham mechanism. The orbiting scroll 50 includes a base plate 50a and a second scroll body 50b having an involute curve shape and erected on one surface of the base plate 50a. An orbiting bearing 50c formed in a bottomed cylindrical shape is formed in a substantially central part on an undersurface of the base plate 50a. An eccentric shaft portion 16a installed on an upper end of a rotating shaft portion 16 described later is inserted in orbiting bearing 50c, in order to cause the orbiting scroll 50 to orbit.

The second scroll body 50b is configured to be engaged with the first scroll body 40b to form a compression chamber between the first scroll body 40b and the second scroll body 50b. The orbiting scroll 50 is configured to orbit opposed to the fixed scroll 40.

The motor element 20 includes an electric motor stator 22 fixed to the inner circumferential surface of the sealed container 10 through shrink fit or other method, an electric motor rotor 24 rotatably housed on an inner circumferential side of the electric motor stator 22, and a rotating shaft portion 16 (main shaft) fixed to the electric motor rotor 24 through shrink fit or other method. The electric motor stator 22 is connected to a glass terminal (not shown) via lead wires. The electric motor stator 22 is supplied with electric power from outside via the glass terminal and lead wires. The electric motor rotor 24 is configured to rotate as electric power is supplied to the electric motor stator 22 and transmit a driving force to the orbiting scroll 50 through the rotating shaft portion 16.

A main shaft portion 16b located above the electric motor rotor 24 in the rotating shaft portion 16 is rotatably supported in a radial direction by a cylindrical main bearing 17 installed under the base plate 50a. The main shaft portion 16b is fitted in the main bearing 17 and slides along the main bearing 17 and an oil film of a lubricating oil. The eccentric shaft portion 16a eccentric to the main shaft portion 16b is installed on the upper end of the rotating shaft portion 16. A countershaft portion 16c located below the electric motor rotor 24 in the rotating shaft portion 16 is rotatably supported by the sub-frame 13. An axis of the main shaft portion 16b and an axis of the countershaft portion 16c are the same as an axis of the rotating shaft portion 16.

A pump element 18 such as a positive displacement pump is installed at a lower end of the rotating shaft portion 16. The pump element 18 supplies the refrigerating machine oil accumulated in the oil sump 14 to the sliding parts such as the main bearing 17. The pump element 18 is mounted on the sub-frame 13 and supports the rotating shaft portion 16 in the axial direction on an upper end surface of the pump element 18.

FIG.2 is an end view taken along line II - II of FIG.1. As shown in FIG.2, the first scroll body 40b of the fixed scroll 40 and the second scroll body 50b of the orbiting scroll 50 are engaged with each other in opposite phases to each other (phase difference of 180 degrees). Scroll involute directions of both the first scroll body 40b and the second scroll body 50b correspond to a counter-clockwise direction in FIG.2. A compression chamber configured to compress the fluid is formed between the first scroll body 40b and the second scroll body 50b.

An inlet port 32 is formed between the first scroll end portion 42 of the outermost tooth 40b 1 of the first scroll body 40b and a second tooth 40b2 which is positioned at the center side of the scroll compression element 30 and closest to the outermost tooth 40b 1. The inlet port 32 sucks the fluid from the injection pipe 60 into the compression.

The injection pipe 60 penetrates a side face of the sealed container 10. The fluid (low pressure gas refrigerant) sucked from outside flows into the scroll compression element 30 through the injection pipe 60. The injection pipe 60 is arranged inclinedly with respect to the radial direction of the sealed container 10 so that an opening 62 of the injection pipe 60 on the inner side of the sealed container 10 faces to a first scroll end portion 42 of an outermost tooth 40b 1 of the first scroll body 40b. Namely, the injection pipe 60 is arranged so that an axis line of the injection pipe 60 is not orthogonal to a tangent surface of the peripheral surface of the sealed container 10.

Moreover, for the purpose of reducing the flow loss of the fluid, an axis line C of the injection pipe 60 extends between the first scroll end portion 42 of the first scroll body 40b and the nearest position to the first scroll end portion 42 on the second tooth 40b2. Namely, a direction of an axis line C of the injection pipe 60 is oriented toward a gap between the first scroll end portion 42 of the first scroll body 40b and the nearest position to the first scroll end portion 42 on the second tooth 40b2.

It is preferable that the axis line of the injection pipe 60 extends a center position between the first scroll end portion 42 of the first scroll body 40b and the nearest position to the first scroll end portion 42 on the second tooth 40b2, for the purpose of further reducing the flow loss of the fluid. It is more preferable that the axis line of the injection pipe 60, at the center position, is orthogonal to a face which includes the first scroll end portion 42 of the first scroll body 40b and the nearest position to the first scroll end portion 42 on the second tooth 40b2, for the purpose of furthermore reducing the flow loss of the fluid.

Furthermore, the tangential direction of the first scroll body 40b at the position of the first scroll end portion 42 is parallel with the axis line of the injection pipe 60. As such, the fluid which is injected from the opening 62 of the injection pipe 60 smoothly flows to the inlet port 32. As such, it is possible to reduce the pressure loss / flow loss of the fluid around the periphery of the inlet port 32.

As shown in FIG.2, a length of the first scroll body 40b is longer than that of the second scroll body 50b, so that a second scroll end portion 52 of the second scroll body 50b is positioned at the vicinity of the first scroll end portion 42. As such, it is possible to avoid flowing the fluid to the outside of the outermost tooth 40b 1 of the first scroll body 40b, in the sucking step. As a result, it is possible to reduce the flow loss more securely.

Next, the flow of the fluid (gas refrigerant) which flows to the scroll compressor 100 will be described.

Firstly, the injection fluid (low pressure gas refrigerant) flowing from the opening 62 of the injection pipe 60 is injected and flowed into the inlet port 32 of the scroll compression element 30. Since the injection pipe 60 is arranged inclinedly with respect to the radial direction of the sealed container 10, it is not necessary to bend the injection pipe 60 so as to direct the fluid to the inlet port 32 of the scroll compression element 30. As such, it is possible to reduce the pressure loss of the fluid in the inside of the injection pipe 60.

Moreover, since the opening 62 of the injection pipe 60 on the inner side of the sealed container 10 faces to the first scroll end portion 42 of an outermost tooth 40b 1 of the first scroll body 40b, it is possible to reduce the occurrence of the pressure loss of the fluid (gas refrigerant) between the opening 62 of the injection pipe 60 and the scroll compression element 30.

FIG.5 (a) to FIG.5(d) are diagrams illustrating relative oscillatory motion of the first scroll body 40b and the second scroll body 50b for one cycle in a section shown in FIG.2. FIG.5(a) to FIG.5(d) show states in rotation phases of 0 degrees, 90 degrees, 180 degrees, and 270 degrees. The rotation phase at a time point when the fluid starts to be sucked into the compression chamber is assumed to be 0 degrees. The hatching areas in FIG.5(a) to FIG.5(d) show the fluid sucked in the scroll compression element 30. As shown in FIG.5(a) to FIG.5(d), with increases in the rotation phase from 0 degrees, the sucked fluid is compressed between the first scroll body 40b and the second scroll body 50b, meanwhile the compressed fluid is moved into the center of the scroll compression element 30.

And then, the compressed fluid is discharged as the compressed fluid (high pressure gas refrigerant) through an outlet opening 34 which is located at the center of the scroll compression element 30.

Although specific embodiments of the invention have been disclosed and described as well as illustrated in the companying drawings, it is simply for the purpose of better understanding of the principle of the present invention and it is not as a limitation of the scope and spirit of the teaching of the present invention. Adaption and modification to various structures such as design or material of the invention are possible and apparent to a skilled person without departing from the scope of the present invention which is to be determined by the claims.

List of reference:

100: scroll compressor

10: sealed container

12: middle shell

13: sub-frame

14: oil sump

15: discharge pipe

16: rotating shaft portion

16a: eccentric shaft portion

16b: main shaft portion

16c: countershaft portion

17: main bearing

18: pump element

20: motor element

22: electric motor stator

24: electric motor rotor

30: scroll compression element

32: inlet port

34: outlet opening

40: fixed scroll

40a: base plate 40b: first scroll body 40b 1: outermost tooth 40b2: second tooth 42: first scroll end portion 44: discharge port

50: orbiting scroll 50a: base plate 50b: second scroll body 50c: orbiting bearing 52: second scroll end portion

60: injection pipe 62: opening

Claims

1. A scroll compressor comprising: a sealed container; a motor element housed in the sealed container; a scroll compression element housed in the sealed container and configured to be driven by a rotating shaft portion of the motor element; and an injection pipe mounted penetratingly a side face of the sealed container, in which gas refrigerant sucked from outside flows into the scroll compression element, wherein the scroll compression element including a fixed scroll including a first scroll body and an orbiting scroll including a second scroll body configured to be engaged with the first scroll body to form a compression chamber between the first scroll body and the second scroll body, the orbiting scroll being configured to orbit opposed to the fixed scroll, and wherein the injection pipe is arranged inclinedly with respect to the radial direction of the sealed container so that an opening of the injection pipe on the inner side of the sealed container faces to a first scroll end portion of an outermost tooth of the first scroll body.

2. The scroll compressor of claim 1, wherein the first scroll body includes the outermost tooth and a second tooth which is positioned at the center side of the scroll compression element and closest to the outermost tooth, and wherein a direction of an axis line of the injection pipe is oriented toward a gap between the first scroll end portion of the first scroll body and the nearest position to the first scroll end portion on the second tooth.

3. The scroll compressor of claim 1, wherein the tangential direction of the first scroll body at the position of the first scroll end portion is parallel with the axis line of the injection pipe.

4. The scroll compressor of claim 1, wherein a length of the first scroll body is longer than that of the second scroll body, so that a second scroll end portion of the second scroll body is positioned at the vicinity of the first scroll end portion.