JP2003003961A - Hermetic compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hermetic compressor which can accurately measure dilution of lubricating oil supplied to a slide part by arranging a dilution sensor for measuring dilution indicating proportion of a refrigerant dissolved into the lubricating oil in a supply oil passage between an oil suction pipe and an oil hydraulic pump. SOLUTION: This hermetic compressor arranges an electric motor and a compression part in a hermetic vessel having an oil reservoir 7 accumulating lubricating oil 7a in a bottom part for transmitting turning force of the electric motor to the compression part and is constituted of a shaft provided with an oil feed path 8a drilled in the inside and an oil supply mechanism sucking the lubricating oil 7a from the oil reservoir 7 to supply it to a slide part of the compression part from one end of the shaft through the oil feed path 8a. A dilution sensor 15 for measuring the dilution indicating the rate of a refrigerant dissolved into the lubricating oil 7a is arranged in a supply oil passage sucking the lubricating oil 7a from the oil reservoir 7 into the oil supply mechanism.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hermetic compressor used in an air conditioner or the like, and more specifically, a change in relative permittivity of lubricating oil and a refrigerant is regarded as a change in capacitance between both electrodes. The present invention relates to an oil dilution measuring method in which a dilution sensor for detecting is provided in an oil supply passage.

[0002]

2. Description of the Related Art In a conventional hermetic compressor using a refrigerant used in an air conditioner or the like, an oil compatible with the refrigerant is often used as an oil for lubricating a sliding portion of the compressor. This is to make it easier for the oil discharged to the outside of the compressor to return to the inside of the compressor. However, depending on the operating conditions, a large amount of the refrigerant dissolves in the oil, which reduces the viscosity of the oil and may damage the sliding portion of the compressor. In order to avoid the above-mentioned poor lubrication, many reliability tests have been conventionally performed under various conditions.

Further, as disclosed in Japanese Patent Application Laid-Open No. 5-5562, there is a technique of installing a dilution sensor in the compressor and reflecting the information in the operation control. The measurement of the degree of dilution uses the difference in the relative dielectric constants of oil and refrigerant. When the amount of the refrigerant dissolved in the oil (refrigerant dilution degree) changes and the relative dielectric constant changes, the capacitance between the electrodes provided in the oil changes. The change in refrigerant is measured by detecting this change.

Since the dilution degree of the refrigerant in the oil sump of the compressor varies, even if the dilution degree sensor is installed at a position distant from the oil suction port, the dilution degree of the oil supplied to the sliding portion is not the same. May be different. Also, at a position away from the oil inlet, the oil flow is small, so the oil between the electrodes stays,
There may be a difference in the degree of dilution between the electrodes and the degree of dilution in the surroundings. As described above, there is a problem in that there is a difference between the dilution degree measured by the sensor and the dilution degree of the oil supplied to the sliding portion.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems. An oil suction pipe for sucking lubricating oil from an oil reservoir and guiding the oil to the oil pump is provided at the bottom of the oil pump. Dilution degree of the lubricating oil supplied to the sliding part is set by arranging the dilution sensor for measuring the dilution degree showing the ratio of the refrigerant dissolved in the lubricating oil in the oil supply passage between the pipe and the oil pump. It is an object of the present invention to provide a hermetic type compressor capable of accurately measuring.

[0006]

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems. An electric motor and a compression unit are arranged in a closed container having an oil reservoir for storing lubricating oil at the bottom. Of the lubricating oil is sucked from the oil reservoir and the shaft provided with an oil feed passage bored inside, and the sliding force of the shaft from one end of the shaft. In a hermetic compressor including an oil supply mechanism that supplies lubricating oil through the oil feed path, the oil supply mechanism is provided with an oil pump, and the oil pump is provided with an oil suction pipe for guiding the lubricating oil from the oil reservoir. , Using the oil suction pipe as an external electrode, and providing a needle-shaped internal electrode inside the oil suction pipe,
A dilution sensor is composed of a pair of these electrodes, and the dilution of the lubricating oil is measured by the change in the detected capacitance between the electrodes due to the difference in the relative permittivity of the lubricating oil and the refrigerant. Has become.

Further, an electric motor and a compression unit are arranged in a closed container having an oil reservoir for accumulating lubricating oil at the bottom, the rotational force of the electric motor is transmitted to the compression unit, and the oil drilled inside is also provided. A shaft provided with a feed path, sucking lubricating oil from the oil reservoir, and sliding part of the compression part from one end of the shaft,
In a hermetic compressor including an oil supply mechanism that supplies lubricating oil through the oil supply path, the oil supply mechanism uses a centrifugal pump action by rotating the shaft by immersing one end of the shaft in the oil reservoir. With the above configuration, a dilution sensor is composed of a pair of electrodes consisting of an upper electrode provided on the outer peripheral portion of the oil intake port of the shaft and a lower electrode provided on the bottom surface of the oil sump, and the dilution sensor has a ratio of lubricating oil to refrigerant. The dilution degree of the lubricating oil is measured by the change in the detected capacitance between the electrodes due to the difference in the dielectric constant.

Further, Teflon (registered trademark) is used as an insulating material for the insulation between the both electrodes.

Further, in the oil supply passage for sucking the lubricating oil,
A temperature sensor for detecting the temperature of the lubricating oil is provided, and the dilution degree of the lubricating oil is corrected by the temperature detected by the temperature sensor.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will now be described in detail as examples based on the drawings. FIG. 1 is a vertical sectional view of a hermetic compressor according to the present invention, and FIG. 2 is an enlarged sectional view of an essential part of the present invention. Here, a scroll type compressor will be described. In the figure, a fixed scroll 4 having an electric motor 2 and a compression unit 3 arranged vertically in a closed container 1 and having a spiral wrap on an end plate 4a, and an orbiting scroll 5 having a spiral wrap on the end plate 5a as well. The compression chamber 3a is formed by meshing with each other to form the compression unit 3, and the discharge chamber 6 from which compressed refrigerant gas is discharged from the compression chamber 3a and the electric motor 2
A compressor is configured by partitioning the motor chamber 2a for housing the above with the compression section 3 and having an oil sump 7 for accumulating the lubricating oil 7a at the bottom.

[0011] The rotational force of the electric motor 2 is transmitted to the compression section 3, and at the same time, lubricating oil is supplied from the oil sump 7 to the compression section 3.
A shaft 8 having an oil feed passage 8a for supplying 7a, a main frame 9 having a main bearing 9a supporting a main shaft 8b formed at one end of the shaft 8, and a sub bearing 10a supporting the other end of the shaft 8. And a sub-frame 10 having Further, a pump chamber 11a is provided below the sub-frame 10 and is arranged in the pump chamber 11a. The pump chamber 11a is connected to the other end of the shaft 8 and is supported by the sub-frame 10 as an oil supply mechanism. An oil pump 11 is provided, and the oil pump 11 supplies oil to the sliding portion of the compression unit 3 via the oil feed passage 8a and collects the supplied lubricating oil 7a in the oil sump 7. Has become. Also, the suction chamber of the compression unit 3
A suction pipe 12 is connected to 3b, and a discharge pipe 13 is connected to the discharge chamber 6.

An oil suction pipe 14 for sucking the lubricating oil 7a from the oil sump 7 and leading to the oil pump 11 is provided below the oil pump 11, and an oil supply passage between the oil suction pipe 14 and the oil pump 11 is provided. To
A dilution sensor 15 for measuring the dilution indicating the ratio of the refrigerant dissolved in the lubricating oil 7a is arranged.

The dilution sensor 15 uses the oil suction pipe 14 as an external electrode P1 and has a needle-shaped internal electrode inside the oil suction pipe 14.
P2 is provided, and the electrodes P1 and P2 are insulated from each other by an insulating material 16 made of Teflon, and lead wires 17 are connected to the electrodes P1 and P2, respectively. It is led out to the outside through a terminal plate 18 provided on the, and this is connected to a measuring circuit 19 for measuring the capacitance.

In the above structure, by the oil pump 11,
When the lubricating oil 7a is sucked from the oil reservoir 7, the lubricating oil 7a is
As indicated by the solid line arrow, the external electrode P1 and the internal electrode P2 are
And flows through the oil pump 11 to the oil feed passage 8a. The measurement of the dilution degree uses the difference between the relative permittivities of the lubricating oil 7a and the refrigerant. When the amount of the refrigerant dissolved in the lubricating oil 7a (refrigerant dilution degree) changes and the relative permittivity changes, the two electrodes The capacitance between P1 and P2 changes. The dilution degree can be measured by detecting and calculating this change in the measuring circuit 19.
As a result, the lubricating oil 7a supplied to the sliding portion of the compression portion 3
Since it reliably passes between the electrodes P1 and P2, the hermetic compressor can accurately measure the dilution degree of the lubricating oil 7a supplied to the sliding portion.

Further, as shown in FIG. 2, a temperature sensor 22 for detecting the temperature of the lubricating oil 7a is provided inside the oil suction pipe 14 for sucking the lubricating oil 7a. By connecting to the circuit 19 and correcting the dilution degree of the lubricating oil 7a based on the temperature detected by the temperature sensor 22, the dilution degree of the lubricating oil 7a due to the temperature change can be measured more accurately. be able to.

FIG. 3 shows another embodiment of the present invention, in which the oil pump 11 is not used in the oil supply mechanism for supplying the lubricating oil 7a to the sliding portion of the compression portion 3 and one end of the shaft 8 is used. Is immersed in the oil sump 7, and the centrifugal pump action by the rotation of the shaft 8 is used.
On the sensor base 20 arranged on the bottom surface of the oil sump 7 with an upper electrode P3 provided on the outer peripheral portion of the oil intake port 8c of the shaft 8 and a lower electrode P4 provided below the upper electrode P3. To
Multiple bolts via Teflon insulation 16a, 16b
It is fixed by 21 and is constituted by connecting lead wires 17 to both electrodes P3 and P4 respectively. This lead wire 17 is led out to the outside via a terminal plate 18 provided on the wall surface of the closed container 1, and this is electrostatically connected. Connected to the measuring circuit 19 for measuring the capacitance.

In the above structure, when the lubricating oil 7a is sucked from the oil reservoir 7 by the centrifugal pump action by the rotation of the shaft 8, the lubricating oil 7a is, as shown by the solid line arrow in FIG.
Flowing between the upper electrode P3 and the lower electrode P4, the oil passage 8a
Flow to. As a result, similarly to the above, the lubricating oil 7a supplied to the sliding portion of the compression portion 3 surely passes between the electrodes P3 and P4, so that the lubricating oil 7a supplied to the sliding portion is diluted. It becomes a hermetic compressor that can measure the degree of accuracy.

As described above, the oil suction pipe 14 that sucks the lubricating oil 7a from the oil sump 7 and guides it to the oil pump 11 is provided below the oil pump 11, and the oil suction pipe 14 and the oil suction pipe 14 are connected to each other. By providing the dilution passage 15 between the oil pumps 11 with the dilution sensor 15 for measuring the dilution ratio showing the proportion of the refrigerant dissolved in the lubricating oil 7a, the lubricating oil 7a supplied to the sliding portion is provided. It becomes a hermetic compressor that can measure the dilution degree of.

[0019]

As described above, in the present invention, an oil suction pipe for sucking lubricating oil from an oil reservoir and guiding it to the oil pump is provided in the lower portion of the oil pump, and an oil supply passage between the oil suction pipe and the oil pump. In addition, a dilution sensor for measuring the degree of dilution that indicates the proportion of the refrigerant dissolved in the lubricating oil is provided in the configuration, so that the dilution degree of the lubricating oil supplied to the sliding part can be measured accurately Become an opportunity.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a hermetic compressor showing an embodiment of the present invention.

FIG. 2 is an enlarged sectional view of an essential part showing an embodiment of the present invention.

FIG. 3 is an enlarged cross-sectional view of an essential part showing another embodiment of the present invention.

[Explanation of symbols]

1 closed container 2 electric motor 2a Electric motor room 3 Compressor 3a compression chamber 3b Inhalation chamber 4 fixed scroll 4a End plate 5 orbiting scroll 5a End plate 6 discharge chamber 7 oil sump 7a lubricating oil 8 shafts 8a Oil line 8b spindle 9 mainframe 9a Main bearing 10 subframe 11 oil pump 11a Oil pump room 12 Inhalation tube 13 Discharge pipe 14 Oil suction pipe 15 Dilution sensor 16 insulation 17 Lead wire 18 terminal board 19 Measuring circuit

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) F25B 49/02 550 F25B 49/02 550 G01N 27/22 G01N 27/22 Z F term (reference) 2G060 AA06 AE40 AF11 AG11 HC10 3H003 AA05 AB03 AC03 BD07 BH02 CF07 3H029 AA02 AA14 AB03 BB01 BB34 BB47 CC09 CC26 CC27 CC34 CC39 CC57 3H039 AA03 AA04 AA12 BB11 BB25 CC27 CC33 CC34 CC44 3H045 AA05 AA16 CA26 FA44 CA44 FA44

Claims (4)

[Claims] 1. An electric motor and a compression unit are arranged in a closed container having an oil reservoir for accumulating lubricating oil at the bottom, and the rotational force of the electric motor is transmitted to the compression unit, and the oil is bored inside. A hermetic seal formed by a shaft having a feed passage and an oil supply mechanism that sucks lubricating oil from the oil reservoir and supplies the lubricating oil from one end of the shaft to the sliding portion of the compression portion through the oil feed passage. In the type compressor, the oil supply mechanism is provided with an oil pump, the oil pump is provided with an oil suction pipe for guiding the lubricating oil from the oil reservoir, the oil suction pipe is used as an external electrode, and the inside of the oil suction pipe is used. A needle-shaped internal electrode is provided on the electrode, and a dilution sensor is configured from the pair of electrodes, and the dilution of the lubricating oil is caused by a change in the detected capacitance between the two electrodes due to the difference in relative permittivity between the lubricating oil and the refrigerant. A hermetic compressor characterized by measuring the degree of dilution. 2. An electric motor and a compression unit are arranged in a closed container having an oil reservoir for accumulating lubricating oil at the bottom, and the rotational force of the electric motor is transmitted to the compression unit, and the oil is bored inside. A hermetic seal formed by a shaft having a feed passage and an oil supply mechanism that sucks lubricating oil from the oil reservoir and supplies the lubricating oil from one end of the shaft to the sliding portion of the compression portion through the oil feed passage. Type compressor, the oil supply mechanism is configured such that one end of the shaft is immersed in the oil reservoir and a centrifugal pump action by rotation of the shaft is utilized, and an upper electrode provided on an outer peripheral portion of an oil suction port of the shaft. And a dilution sensor composed of a pair of electrodes consisting of a lower electrode provided on the bottom surface of the oil reservoir, and a change in the detected capacitance between the two electrodes due to the difference in relative permittivity between the lubricating oil and the refrigerant. To measure the dilution of the lubricating oil Hermetic compressor characterized by comprising Te. 3. The Teflon (registered trademark) is used as an insulating material that insulates the electrodes from each other.
Or the hermetic compressor according to 2. 4. A temperature sensor for detecting the temperature of the lubricating oil is provided in an oil supply passage for sucking the lubricating oil, and the dilution degree of the lubricating oil is corrected by the temperature detected by the temperature sensor. The hermetic compressor according to claim 1, 2 or 3.