阅读说明：本技术 两级螺杆流体机械 (Two-stage screw fluid machine ) 是由 土屋豪 米本龙一郎 岩井聪 于 2019-06-19 设计创作，主要内容包括：本发明提供两级螺杆流体机械,降低高温度的油进入低温度的低压级侧压缩机构部所引起的热损失及因搅拌剩余的油而产生的动力损失,提高能量效率及压缩能力。两级螺杆流体机械具备：低压级侧压缩机构部,包括一边相互啮合一边旋转的第一外转子及第一内转子以及收纳它们的第一壳体,第一外转子、第一内转子以及第一壳体形成第一工作室；以及高压级侧压缩机构部,包括一边相互啮合一边旋转的第二外转子及第二内转子以及收纳它们的第二壳体,第二外转子、第二内转子以及第二壳体形成第二工作室,具有将在第一工作室被压缩了的气体在第二工作室进一步压缩的结构,且具有将滞留于第一工作室或第二工作室或者连接它们的区域的油向第二工作室输送的结构。(The invention provides a two-stage screw fluid machine, which reduces heat loss caused by high-temperature oil entering a low-temperature side compression mechanism part and power loss generated by stirring residual oil, and improves energy efficiency and compression capacity. The two-stage screw fluid machine comprises: a low-stage-side compression mechanism unit including a first outer rotor and a first inner rotor that rotate while meshing with each other, and a first housing that houses the first outer rotor and the first inner rotor, the first outer rotor, the first inner rotor, and the first housing forming a first working chamber; and a high-pressure stage side compression mechanism unit including a second outer rotor and a second inner rotor that rotate while meshing with each other, and a second housing that houses the second outer rotor, the second inner rotor, and the second housing, wherein the second outer rotor, the second inner rotor, and the second housing form a second working chamber, the second working chamber further compresses gas compressed in the first working chamber, and the second working chamber further compresses oil accumulated in the first working chamber, the second working chamber, or a region connecting the first working chamber and the second working chamber to transfer the oil to the second working chamber.)

1. A two-stage screw fluid machine is characterized in that,

the disclosed device is provided with:

a low-stage-side compression mechanism unit including a first outer rotor and a first inner rotor that rotate while meshing with each other, and a first housing that houses the first outer rotor and the first inner rotor, the first outer rotor, the first inner rotor, and the first housing forming a first working chamber; and

a high-pressure stage side compression mechanism unit including a second outer rotor and a second inner rotor that rotate while meshing with each other, and a second housing that houses the second outer rotor and the second inner rotor, the second housing forming a second working chamber,

the two-stage screw fluid machine has a structure in which the gas compressed in the first working chamber is further compressed in the second working chamber, and

the oil pump has a structure for delivering the oil accumulated in the first working chamber, the second working chamber, or a region connecting the first working chamber and the second working chamber to the second working chamber.

2. A two-stage screw fluid machine according to claim 1,

the compressor further includes a driving unit for driving the low-pressure stage compression mechanism unit and the high-pressure stage compression mechanism unit.

3. A two-stage screw fluid machine according to claim 2,

the driving unit is disposed between the low-pressure stage side compression mechanism unit and the high-pressure stage side compression mechanism unit.

4. A two-stage screw fluid machine according to claim 3,

a low-pressure-stage-side oil retention unit is disposed between the drive unit and the low-pressure-stage-side compression mechanism unit.

5. A two-stage screw fluid machine according to claim 3 or 4,

a high-pressure-stage-side oil retention unit is disposed between the drive unit and the high-pressure-stage-side compression mechanism unit.

6. A two-stage screw fluid machine according to claim 3,

the driving unit is a resistance body against the flow of the gas.

7. A two-stage screw fluid machine according to claim 4,

an oil discharge passage is provided between the low-pressure-stage-side oil retention portion and the second working chamber.

8. A two-stage screw fluid machine according to claim 7,

the oil discharge passage is provided with a check valve.

9. A two-stage screw fluid machine according to claim 7,

an ejector is provided in the oil discharge passage.

10. A two-stage screw fluid machine according to any one of claims 1 to 9,

a shaft support part is provided in the first outer rotor, the first inner rotor, the second outer rotor, and the second inner rotor,

the shaft support portion has a structure lubricated by oil,

the oil is retained in the first working chamber, the second working chamber, or the region connecting them, and is sent to the second working chamber.

11. A two-stage screw fluid machine according to claim 10,

at least one of the first outer rotor, the first inner rotor, the second outer rotor, and the second inner rotor has an in-shaft flow passage through which the oil flows.

12. A two-stage screw fluid machine according to claim 3,

a low-pressure stage side oil retention unit is disposed between the driving unit and the low-pressure stage side compression mechanism unit,

a high-pressure-stage-side oil retention unit is disposed between the drive unit and the high-pressure-stage-side compression mechanism unit,

a shaft support part is provided in the first outer rotor, the first inner rotor, the second outer rotor, and the second inner rotor,

the shaft support part has a structure lubricated by oil, and

the oil lubricated by the shaft support portion is supplied to the low-pressure stage side oil retention portion or the high-pressure stage side oil retention portion.

13. A two-stage screw fluid machine according to claim 12,

comprising: a structure for supplying the oil supplied to one of the shaft support portions of the first outer rotor and the first inner rotor to the other shaft support portion; and a structure for supplying the oil supplied to one of the shaft support portions of the second outer rotor and the second inner rotor to the other shaft support portion.

14. A two-stage screw fluid machine according to any one of claims 1 to 13,

the refrigerating machine is used under the condition that the suction temperature of the refrigerant is below-40 ℃.

15. A two-stage screw fluid machine according to any one of claims 1 to 13,

as the refrigerant, at least one of the refrigerants including R448A and R449A is used.

Technical Field

The present invention relates to a two-stage screw fluid machine.

Background

Screw fluid machines are widely used as compressors for refrigeration and air conditioning and air compressors. In particular, the two-stage heat pump apparatus is useful as a heat pump apparatus such as a refrigerator in that the temperature difference can be increased.

Further, in order to promote the spread of two-stage screw fluid machines, further improvement in energy efficiency, high compression capacity, and the like are required.

Patent document 1 describes the following technique: in a two-stage screw compressor integrally constituted with a low-pressure stage and a high-pressure stage, lubricating oil is supplied to a bearing and a shaft seal device of the low-pressure stage screw compressor, and then the lubricating oil is supplied into compression chambers of an outer housing and an inner rotor of the high-pressure stage screw compressor, whereby the amount of degassing of working gas is reduced, the volumetric efficiency is improved, and the compression performance is improved.

Disclosure of Invention

Problems to be solved by the invention

The two-stage screw compressor described in patent document 1 focuses on the amount of the working gas to be degassed, and returns the lubricating oil supplied to the shaft end side bearing and the shaft sealing device to the compression chamber of the high-pressure stage screw compressor, which accommodates the outer rotor and the inner rotor. However, there is no concern about heat loss due to the entry of high-temperature oil into the low-pressure stage side at low temperature, and power loss due to the remaining oil remaining between the low-pressure stage and the high-pressure stage, and there is room for improvement in energy efficiency and the like.

The purpose of the present invention is to reduce heat loss due to entry of high-temperature oil into a low-temperature side compression mechanism and power loss due to stirring of excess oil in a two-stage screw fluid machine, thereby improving energy efficiency and compression capacity.

Means for solving the problems

In order to solve the above problem, the present invention provides a two-stage screw fluid machine including: a low-stage-side compression mechanism unit including a first outer rotor and a first inner rotor that rotate while meshing with each other, and a first housing that houses the first outer rotor and the first inner rotor, the first outer rotor, the first inner rotor, and the first housing forming a first working chamber; and a high-pressure stage side compression mechanism unit including a second outer rotor and a second inner rotor that rotate while meshing with each other, and a second housing that houses the second outer rotor, the second inner rotor, and the second housing, the second outer rotor, the second inner rotor, and the second housing forming a second working chamber, wherein the two-stage screw fluid machine has a structure that further compresses gas compressed in the first working chamber in the second working chamber, and has a structure that conveys oil accumulated in the first working chamber, the second working chamber, or a region connecting the first working chamber and the second working chamber to the second working chamber.

Effects of the invention

According to the present invention, in the two-stage screw fluid machine, it is possible to reduce heat loss due to entry of high-temperature oil into the low-pressure-stage-side compression mechanism section and power loss due to stirring of surplus oil, thereby improving energy efficiency and compression capacity.

Drawings

Fig. 1 is a sectional view showing a two-stage screw fluid machine according to embodiment 1 of the present invention.

Fig. 2 is a sectional view a-a of fig. 1.

Fig. 3 is a sectional view showing a two-stage screw fluid machine according to embodiment 3 of the present invention.

In the figure:

1-a two-stage screw fluid machine, 2-a low-pressure stage side compression mechanism section, 3-a high-pressure stage side compression mechanism section, 4-a drive section, 5-a low-pressure stage side intermediate chamber, 6-a high-pressure stage side intermediate chamber, 10-a suction port, 11-a working chamber suction port, 12-a working chamber discharge port, 13-an outer rotor, 13 a-a spline, 14-an inner rotor, 14 a-spline, 15-a casing, 16-a bore, 17-a suction end face, 18-a discharge end face, 19a, 19b, 20a, 20 b-a shaft support unit, 21, 22, 23, 43, 44-an oil lubrication unit, 21 a-an inlet flow path, 21b, 21c, 21 d-a flow path, 22 a-an inlet flow path, 22 b-a flow path, 23 a-inlet flow path, 30-a discharge port, 31-a working chamber suction port, 32-a working chamber discharge port, 33-an outer rotor, 33 a-spline, 34-an inner rotor, 34a spline, 35-housing, 36-bore, 37-suction end face, 38-discharge end face, 39a, 39b, 40a, 40 b-shaft support unit, 41-auxiliary shaft support unit, 42-gear coupling, 43 a-inlet flow path, 43b, 43c, 43 d-flow path, 44 a-inlet flow path, 44b, 44c, 44 d-flow path, 50-motor, 50 a-stator, 50 b-rotor, 50 c-air gap, 51, 52-oil, 53-oil discharge path, 54-check valve, 60-ejector, 60 a-pressurization port, 60 b-suction port, 60 c-discharge port, 61-discharge flow path, 62-flow path.

Detailed Description

The present invention relates to a two-stage screw fluid machine that handles refrigerants such as HFC systems and HFO systems, natural refrigerants such as air and carbon dioxide, and other compressible gases, and that is provided with a low-stage-side compression mechanism unit and a high-stage-side compression mechanism unit. Therefore, the two-stage screw fluid machine can be applied to an air compressor and a vacuum pump.

Hereinafter, specific embodiments of a two-stage screw fluid machine according to the present invention will be described with reference to the drawings. In the drawings, the same reference numerals denote the same or corresponding parts. The cross-sectional view is a view showing the inside of the two-stage screw fluid machine with the two-stage screw fluid machine arranged as viewed from the side.