JPH08312560A - Electric compressor - Google Patents

Abstract

PURPOSE: To improve the lubrication of the oil on a sliding part of each bearing in the flooded start operation condition so as to improve the reliability in the use of a compressor. CONSTITUTION: A compressing mechanism unit 7, an electric motor 4 for driving this compressing mechanism unit 7, a main shaft 23 for transmitting the rotating force of the electric motor 4 to the compressing mechanism unit 7, and an oil pump 24 for supplying the lubricating oil to a sliding part of the compressing mechanism unit 7 are provided in a sealed container 1 having an oil reservoir in the bottom part thereof. Furthermore, a suction port 30, which can be moved in the vertical direction, is provided in a suction pipe 24a of the oil pump 24.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric compressor used for cooling and heating, or a cooling device such as a refrigerator.

[0002]

2. Description of the Related Art Conventionally, electric compressors such as rotary compressors and scroll compressors have been used as cooling devices for cooling and heating, or refrigerators.

Next, a scroll compressor as a conventional representative example will be described with reference to FIG. 4 (JP-A-2-27186).

In FIG. 1, the shell 51 is composed of a cylindrical body having a central axis extending in the horizontal direction.
The shell 51 is provided with an oil sump 52 for storing oil for lubricating each bearing sliding portion at the bottom, and a compression mechanism assembly 53 for compressing the working fluid is provided inside. The compression mechanism assembly 53 includes a fixed scroll 54 and an orbiting scroll 5 which are eccentrically combined with each other.
5 and swing scroll 55 of these scrolls
It is constituted by an assembly having a motor stator 56 and a motor rotor 57 for driving the motor. Fixed scroll 5
4 has a discharge port 54a, a gas suction port 54b, and a spiral wrap 54c, and is fixed to a bearing support 58. 5
Reference numeral 9 is a main shaft that connects the orbiting scroll 55, is supported by the bearing support 58, is provided in the shell 51, and is configured to be rotated by a motor A including the motor stator 56 and a motor rotor 57. There is. The main shaft 59 has the bearing sliding portion 3
4 and an oil hole 59b which is open at the lower end and communicates with an oil supply passage 59a extending in the axial direction and which is open in the radial direction. Reference numeral 60 denotes a housing having a tubular body 61 facing the oil sump 27, which is provided in the axial direction of the orbiting scroll 55 and is fixed to the motor stator 56 of the motor A by bolts or the like. This housing 60
The pipe body of (1) communicates with a suction space portion of a pump described later via the first oil hole 60a. Reference numeral 62 is a positive displacement pump driven by the rotation of the main shaft 59.
Trochoid pump 62 having a and a pump motor 62b
And is housed inside the housing 60. 66 is a suction pipe for sucking the working fluid into the shell,
Located near the coil end of the motor stator 56,
For example, it is attached to the upper portion of the motor side end plate of the shell 51 by brazing.

In the scroll compressor thus constructed, when the motor A is driven, the working fluid gas is drawn from the suction pipe 66 to the suction space above the coil end of the motor stator 56 as shown by the solid arrow in FIG. After being sucked into 29, it passes through the gap between the outer peripheral surface of the motor stator 56 and the inner peripheral surface of the shell 51 to cool the motor, and then passes through the notch 58c above the bearing support 58 and passes through the gas suction port 54.
It is taken into the compression chamber 13 from b. On the other hand, the oil flows as shown by the wavy arrow in FIG. That is, when the pump rotor 62b is rotated by the rotation of the main shaft 59, the pump 62 is driven by the driven of the pump stator 62a, so that the oil flows from the pipe body 61 into the suction space of the pump 62 through the first oil hole. From the discharge chamber of the pump 62 to the frame 6
4 is oil-fed to the oil supply passage 59a through the oil hole 59c, and the recess 58b of the bearing support 58 and the oil hole 59b of the main shaft 59.
Is supplied to the bearing sliding portions 18, 34, 37, 38 via. Then, the oil flows out from the bearing sliding portion 18, flows into the oil discharge chamber 58a, and returns to the oil sump 52 from the opening of the oil discharge chamber 58a.

[0006]

By the way, in the compressor provided with the suction port of the oil pump 62 near the bottom as described above, when the lubricating oil is compatible with the refrigerant, lubrication is performed during steady operation. The oil dissolves well in the refrigerant, and the oil is pumped up by the pump 62, so that it is possible to sufficiently supply oil to each bearing sliding part, but the ambient temperature of the compressor is extremely low, and the operation is stopped for a long time. If
Since the lubricating oil and the refrigerant in the compressor are close to the separated state, and the specific gravity of the oil is lighter than that of the refrigerant at the time of restart, there is a large amount of the refrigerant in the lower part. There is a problem in that the lubricity deteriorates, resulting in burnout, which reduces reliability in use of the compressor. Also,
In the case where the lubricating oil is incompatible with the refrigerant, the separated state may continue and the lubricity may be deteriorated not only at the time of starting to sleep but also at the time of stable operation, similarly to the above.

The present invention has been made in view of the above circumstances, and it is possible to prevent the occurrence of burnout in the sliding portions of the bearings, and thus to reliably improve the reliability in use of the compressor. A compressor is provided.

[0008]

In order to solve the above problems, the present invention, as a first means, drives a compression mechanism part and this compression mechanism part in a closed container having an oil sump at the bottom. The motor includes an electric motor, a main shaft that transmits the rotational force of the electric motor to the compression mechanism unit, and an oil pump that supplies lubricating oil to a sliding portion of the compression mechanism unit. A suction pipe that is vertically movable in a suction pipe of the oil pump. This is an electric compressor having a mouth.

As a second means, the suction pipe of the oil pump is provided with a float.

As a third means, the suction pipe of the oil pump is made of a bendable member.

As a fourth means, a vertical slide movable portion is provided on at least a part of the suction pipe of the oil pump.

[0012]

The operation of the above means is as described below.

According to the first means, the suction port can be provided at an appropriate height depending on the compatibility of the oil and the refrigerant,
As a result, oil having a relatively high viscosity is sucked into the oil pump.

Further, according to the second means, by providing the float in the pump suction pipe, not only during stable operation, but the oil and the refrigerant are in a state close to two-phase separation, and the oil is present at the upper part. However, the suction port can always be moved according to the oil level surface.

According to the third means, by making the suction pipe a bendable member, it can be moved to various places in the oil and the refrigerant, and even if there is uneven compatibility, it is relatively It is possible to guide the oil to high-viscosity oil.

According to the fourth means, since the suction port is always provided downward by making a part of the suction pipe slidable up and down, oil is easily sucked and the structure is relatively simple. It can be anything.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a first embodiment of the present invention. In the figure, 1 is a closed container, 2 is a suction pipe, and 3 is a discharge pipe. Reference numeral 4 is an electric motor, 5 is a stator of the electric motor, 6 is a rotor of the electric motor, and 7 is a compression mechanism portion. Reference numeral 23 is a main shaft, and 22 is a crankshaft for transmitting the rotational force of the electric motor to the compression mechanism section 7. Since this embodiment is a scroll compressor, the compression mechanism section 7 is composed of an orbiting scroll 13, a fixed scroll 8, an orbiting bearing 18, a bearing component 19, and the like. The bearing component 19 supports the large shaft portion of the crankshaft 22. A partition member 12 is fixed to the closed container 1, and the closed container 1 and the discharge pipe 3 are provided in the space where the compression mechanism portion 7 exists.
The space is divided into two.

At the center of the partition member 12, a main shaft 23
A second bearing 29 is mounted to support one end of the. Further, the partition member 12 has a gas ejection hole 31 through which the refrigerant gas passes.
Is provided. Then, a gas collision plate 32 is provided at a position facing the gas ejection hole 31. Reference numeral 24 is an oil pump for supplying lubricating oil to the sliding portion of the compression mechanism portion 7,
A part of the suction pipe 24a of the oil pump is provided with a vertically expandable pipe 30 made of a light material that can float with respect to the refrigerant or oil. Further, the suction plate provided with the suction pipe 24a of the oil pump 24 is extended to form the gas collision plate 32. 28 is a box configured so as to surround the circumference of the discharge pipe 3.

Next, the operation of the scroll compressor having such a configuration will be described. The flow of the refrigerant gas is indicated by a thick arrow.

As the electric motor rotor 6 rotates, the crankshaft 22 and the orbiting bearing 18 rotate, and as a result, the orbiting scroll 13 orbits around the fixed scroll 8,
A compression action occurs in the space surrounded by the orbiting scroll blade 15 and the fixed scroll blade 9. Then, the low-pressure refrigerant gas is sucked through the suction pipe 2, and the orbiting scroll blade 1
It is compressed in the space between the fixed scroll blade 5 and the fixed scroll vane 5 and discharged from the discharge hole 10 into the closed container 1. After that, the high-pressure refrigerant gas passes through the gas passage 26 provided in the compression mechanism portion 7,
After passing through the gas passage 27 of the electric motor stator 5, it passes around the oil pump 24, wraps around the box 28, and finally goes out of the closed container 1 through the discharge pipe 3.

On the other hand, the flow of oil is indicated by a thin arrow. During normal operation, the oil 25 collected in the lower part of the closed container 1 is sucked by the oil pump 24 and, after being pressurized, passes through the oil passage 33 of the crankshaft 22 and first between the orbiting scroll shaft 17 and the orbiting bearing 18. Lubricate the sliding surface. After that, the oil reaches the back surface of the end plate 14, but since the annular seal member 21 is provided on the back surface of the end plate 14, the oil is stopped by the seal member 21. The oil on the back surface of the end plate 14 then flows while lubricating the sliding portion between the large shaft portion of the crankshaft 22 and the bearing component 7, is discharged into the bearing cover 27, and then returns to the inside of the closed container 1.

However, even if the lubricating oil is compatible with the refrigerant when the compressor ambient temperature is very low, the operation is stopped, and the oil and the refrigerant are laid in the compressor, Depending on such conditions, oil may separate from the refrigerant and form a phase above the refrigerant due to its low specific gravity. As a result, at the time of start-up, the vicinity of the suction pipe 24a of the oil pump 24 sucks a refrigerant having a small oil phase and a low viscosity, which also causes a decrease in the lubricity of the sliding portion.
Therefore, in the first embodiment, by forming a bellows-shaped pipe 30, which is lighter than the specific gravity of each of the refrigerant and the oil, in at least a part of the suction pipe 24a, it expands and contracts according to the oil surface, and always maintains the oil surface. A suction port can be present in the vicinity, so that a relatively high-viscosity oil can be sucked in and the lubricity to each sliding portion can be improved.

In the second and third embodiments shown in FIG. 2, as another method of holding the suction port of the pump 24 near the oil surface, a float 34 is provided on the suction pipe 24a of the oil pump. By making the suction pipe 24a by a bendable member, the float 34 lifts the suction pipe 24a to an appropriate oil region, guides it, sucks oil, and improves lubricity to each sliding portion. You can

Further, as a fourth embodiment shown in FIG. 3, a vertical slide movable portion 35 is provided on at least a part of the oil pump suction pipe 24a, and the float 3 is provided around it.
It is the one with 4.

Due to the float 34, the suction port is movable according to the oil level, and the suction port is always open downward, so that the oil is easily sucked.

[0027]

As described above, according to the present invention,
A compression mechanism part, an electric motor for driving the compression mechanism part, a main shaft for transmitting the rotational force of the electric motor to the compression mechanism part, and a sliding movement of the compression mechanism part in a closed container having an oil sump at the bottom. An oil pump for supplying lubricating oil is provided in the portion, and a vertically movable suction port is provided in the suction pipe of the oil pump, so that the suction port is provided at an appropriate height depending on the compatibility state of oil and refrigerant. As a result, oil having a relatively high viscosity is sucked into the oil pump, and the lubricity of the sliding portion can be improved.

Further, according to the present invention, by providing a float in the pump suction pipe, not only during stable operation but also when the oil and the refrigerant are in a state close to two-phase separation and the oil is present in the upper part, Since the suction port is always movable according to the oil level surface, it is possible to suck in highly viscous oil and to perform good lubrication on each sliding portion.

Further, according to the present invention, by making the suction pipe a bendable member, the suction pipe can be moved to various places in the oil and the refrigerant, and the viscosity is relatively high even if there is uneven compatibility. You can freely lead to the place of oil.

Further, in the present invention, since the suction port is always provided downward by making a part of the suction pipe slidable up and down, oil can be easily sucked and the structure is relatively simple. it can.

[Brief description of drawings]

FIG. 1 is a sectional view of a scroll compressor showing a first embodiment of the present invention.

FIG. 2 is a cross-sectional view of essential parts near an oil pump of a scroll compressor showing Embodiments 2 and 3 of the present invention.

FIG. 3 is a cross-sectional view of an essential part near an oil pump of a scroll compressor showing a fourth embodiment of the present invention.

FIG. 4 is a sectional view of a conventional scroll compressor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Airtight container 2 Suction pipe 3 Discharge pipe 4 Electric motor 7 Compression mechanism part 22 Crankshaft 23 Main shaft 24 Oil pump 25 Oil sump part 30,35 Suction pipe moving part 34 Float

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yoshiyuki Nigami 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (4)

[Claims] 1. A compression mechanism section for compressing a refrigerant, an electric motor for driving the compression mechanism section, and a spindle for transmitting the rotational force of the electric motor to the compression mechanism section in a closed container having an oil sump at the bottom. And an oil pump for supplying lubricating oil to the sliding portion of the compression mechanism, and an up / down movable suction port is provided in a suction pipe of the oil pump. 2. The electric compressor according to claim 1, wherein the suction pipe of the oil pump is provided with a float. 3. The electric compressor according to claim 1, wherein the suction pipe of the oil pump is formed of a bendable member. 4. The electric compressor according to claim 1, wherein at least a part of the suction pipe of the oil pump is provided with a vertically slidable movable portion.