JP6301036B2 - Compressor - Google Patents

Description

  The present invention relates to a compressor using a lubricating oil and further a combustible refrigerant.

  Some refrigerators have a compressor, a condenser, an expansion mechanism, and an evaporator, which are connected by a refrigerant pipe. The compressor includes a compression element that compresses the refrigerant, an electric element that drives the compression element, a rotating shaft that connects the electric element and the compression element, a cup muffler that covers the compressed gas discharge part of the compression element, and a bottom part that includes these. It has an airtight container in which lubricating oil is stored. When the electric motor mounted on the compressor is driven, the refrigerator is discharged after the refrigerant is compressed by the compressor, condensed by the condenser, depressurized by the expansion mechanism, evaporated by the evaporator, and again into the compressor. Inhaled.

Thus, during the operation of the compressor, the pressure in the refrigerator is a positive pressure higher than the atmospheric pressure from the discharge port of the compressor to the inlet of the expansion mechanism, and the suction port of the compressor from the outlet of the expansion mechanism The pressure up to is a negative pressure lower than atmospheric pressure.
Therefore, if a hole is formed in the refrigerant pipe that becomes the refrigerant flow path from the outlet of the expansion mechanism of the refrigerator to the inlet of the compressor due to corrosion, poor welding, or the like, the refrigerant circuit that forms the refrigerating cycle of the refrigerator Air may be inhaled.
Further, for example, the connection position between the pipes may deviate from a preset position due to an artificial cause such as assembly, installation, and removal of the refrigerator. Even in such a case, air may be sucked into the refrigerant circuit constituting the refrigeration cycle of the refrigerator due to the operation of the compressor.

Thus, the air sucked into the refrigerant circuit of the refrigerator is compressed by the compressor and mixed with the lubricating oil that is steam, mist, etc. to form a combustible mixture. Or, if the combustible refrigerant such as isobutane, propane, R32, or the like is adopted as the refrigerant, the air sucked into the refrigerant circuit of the refrigerator is mixed with these refrigerants to form a combustible mixture. To do.
Here, there is a possibility that the combustible mixture formed as described above is ignited or ignited and the flame is propagated to the entire refrigerator. That is, due to the operation of the compressor, the combustible mixture formed as described above becomes high pressure and high temperature, and may ignite or ignite, and the compressor and further the refrigerator may be damaged.

Therefore, in order to suppress such problems, the conventional refrigerator has an oxygen adsorbent made of reduced iron or activated carbon and an oxygen adsorbent in a refrigeration cycle having a compressor, a condenser, an expansion mechanism, and an evaporator. A case in which a housing case and a transmission plate that permeates oxygen in the refrigeration cycle and partitions the oxygen adsorbent and the refrigeration cycle is proposed (see, for example, Patent Document 1).
The refrigerator described in Patent Literature 1 is configured to adsorb and remove oxygen contained in the air circulating in the refrigerant circuit together with the refrigerant by providing a case for storing the oxygen adsorbent in the refrigerant circuit. .

JP 2000-320911 A

  The technique described in Patent Document 1 cannot suppress an increase in the combustible air-fuel mixture when oxygen at or above the adsorption rate by the stored oxygen adsorbent or at least the adsorption capacity is sucked into the refrigerant circuit. That is, in the technique described in Patent Document 1, an oxygen adsorbent is used, and oxygen in the combustible mixture cannot be removed from the refrigerant circuit with high efficiency. For this reason, the air that could not be removed in the refrigerant circuit increased, and the formed combustible air-fuel mixture could ignite, which could damage the compressor and further the refrigerator.

  Furthermore, the technique described in Patent Document 1 is intended to adsorb and remove oxygen in the combustible air-fuel mixture by connecting an oxygen absorber to the upper part of the outlet of the condenser. On the other hand, the applicant experimentally verified the ignition and explosion phenomena when air was sucked into the refrigerator, as will be described later. As a result, the compressed air, lubricant vapor, mist, refrigerant, and flammable mixture are compressed by the compressor, resulting in a high-temperature and high-pressure flammable mixture. The combustible mixture is ignited inside the compressor. Then, it was clarified that an explosion occurred. And even if it provided the oxygen adsorption apparatus in refrigerant circuits other than a compressor, it turned out that the suppression effect of ignition and an explosion has no effect at all. Therefore, in the technique described in Patent Document 1, the formed combustible air-fuel mixture may ignite, and the compressor and the refrigerator may be damaged.

  The present invention solves the problems as described above, and suppresses an increase in the combustible air-fuel mixture formed by the air sucked into the compressor and compressed and the lubricating oil or combustible refrigerant, and is combustible. An object of the present invention is to provide a compressor that does not break even when a sex mixture is ignited.

  A compressor according to the present invention includes a compression element that compresses a refrigerant, an electric element that drives the compression element, a rotating shaft that connects the electric element and the compression element, and a compressed gas of the compression element that is discharged by the compressed refrigerant. In a compressor having a cup muffler that covers the discharge part and a sealed container that contains these and stores the lubricating oil at the bottom, the compressed gas is in contact with the compressed gas discharge part side of the cup muffler or in contact with the cup muffler. In the air mixed in the compressed gas discharged from the compressed gas discharge part on the opposite side of the discharge part, or on the compressed gas discharge part side of the cup muffler and on the opposite side of the compressed gas discharge part in contact with the cup muffler An ignitable substance that helps ignite or start combustion of a flammable refrigerant or lubricating oil is installed.

  Since the compressor according to the present invention has the above-described configuration, when air is sucked into the compressor, the cup muffler covering the compressed gas discharge part inside the compressor, or the cup side The heating element provided on the opposite side of the compressed gas discharge part in contact with the muffler, or on the side of the compressed gas discharge part of the cup muffler and on the opposite side of the compressed gas discharge part in contact with the cup muffler is sucked in. Reacts with oxygen in the air and generates heat. Then, the heating element that generates heat by reacting with oxygen ignites the formed combustible mixture while the pressure inside the compressor is not high, thereby increasing the combustion pressure several times the pressure immediately before the explosion. The pressure generated by the explosion can be kept low, and the breakage of the compressor and further the refrigerator can be suppressed.

1 is an overall configuration diagram of a refrigerator having a compressor according to Embodiment 1 of the present invention. It is a longitudinal cross-sectional view of the compressor by Embodiment 1 of this invention. It is the top view (a) of the cup muffler of the compressor by Embodiment 1 of this invention, and its XX direction sectional drawing (b). It is the top view (a) of the other cup muffler of the compressor by Embodiment 1 of this invention, and its XX direction sectional drawing (b). It is the top view (a) of another another cup muffler of the compressor by Embodiment 1 of this invention, and its XX direction sectional drawing (b). In the compressor by Embodiment 1 of this invention, it is explanatory drawing which showed an example of the experimental result of the temperature change of each part in the compressor according to the time passage during the air suction by the driving | operation of a compressor. In the compressor according to the first embodiment of the present invention, the pressure and temperature of the air-fuel mixture in the compressor, the self-ignition temperature of the lubricating oil, and the oxidation heating element according to the time elapsed after the start of air suction into the compressor. It is explanatory drawing which showed the relationship with temperature. It is explanatory drawing which showed the relationship between the pressure before combustion of the compressor by Embodiment 1 of this invention, and the pressure after combustion. It is the top view (a) of the cup muffler of the compressor by Embodiment 2 of this invention, and its YY direction sectional drawing (b). It is the top view (a) of the other cup muffler of the compressor by Embodiment 2 of this invention, and its YY direction sectional drawing (b). It is the top view (a) of another other cup muffler of the compressor by Embodiment 2 of this invention, and its YY direction sectional drawing (b). MnO _2, a diagram showing a comparison of lubricant degradation properties of _{Mn 2 O 3, Mn 3 O} 4, Ru. Is a graph showing the results of examining the oxidation time of the lubricating oil by the oxidation catalyst MnO _2. In the compressor according to the second embodiment of the present invention, the relationship between the pressure and temperature of the air-fuel mixture in the compressor and the self-ignition temperature of the lubricating oil over time after the start of air suction into the compressor is shown. It is explanatory drawing shown. It is explanatory drawing which showed the relationship between the pressure before combustion of the compressor by Embodiment 2 of this invention, and the pressure after combustion. It is the top view (a) of the other cup muffler of the compressor by Embodiment 2 of this invention, and its ZZ direction sectional drawing (b). It is the top view (a) of another cup muffler of the compressor by Embodiment 2 of this invention, and its ZZ direction sectional drawing (b). It is the top view (a) of another another cup muffler of the compressor by Embodiment 2 of this invention, and its ZZ direction sectional drawing (b). It is the top view (a) of the cup muffler of the compressor by Embodiment 3 of this invention, and its XX direction sectional drawing (b). It is a whole block diagram of the refrigerator which has a compressor by Embodiment 4 of this invention.

  Hereinafter, a compressor according to an embodiment of the present invention will be described. In addition, this invention is not limited by this embodiment. Further, the constituent elements of this embodiment include those that can be replaced while maintaining the identity of the invention and that are obvious for replacement. In addition, a plurality of modifications described in this embodiment can be arbitrarily combined within a range obvious to those skilled in the art.

Embodiment 1 FIG.
FIG. 1 is an overall configuration diagram of a refrigerator having a compressor according to Embodiment 1 of the present invention. FIG. 2 is a longitudinal sectional view of the compressor according to Embodiment 1 of the present invention. 3A is a plan view of a cup muffler of the compressor according to the first embodiment of the present invention, and FIG. Hereinafter, with reference to FIGS. 1-3, the structure of the compressor by Embodiment 1 of this invention and the refrigerator which has this compressor is demonstrated.

[Description of configuration]
The refrigerator 100 is used for an air conditioner, a refrigerator such as a refrigerator and a freezer, a water heater, and the like. The case where the refrigerator 100 having the compressor 1 according to Embodiment 1 of the present invention is used in an air conditioner will be described as an example.
As shown in FIG. 1, a refrigerator 100 includes a compressor 1 that compresses and discharges a refrigerant, a first heat exchanger 2 that functions as a condenser or an evaporator, an expansion valve 3 that decompresses the refrigerant, and evaporation. A second heat exchanger 4 that functions as a condenser or a condenser, a four-way valve 5 that switches a refrigerant flow path, a muffler 6 that reduces pulsation of refrigerant discharged from the compressor 1, and excess refrigerant are stored. And an accumulator 7 that can be used.
The refrigerator 100 also includes a refrigerant pipe 9 that connects the compressor 1, the first heat exchanger 2, the expansion valve 3, the second heat exchanger 4, the four-way valve 5, the muffler 6, the accumulator 7, and the like. . Of the refrigerant pipes 9, the refrigerant pipe 9 connecting the compressor 1 and the first heat exchanger 2 is referred to as a discharge refrigerant pipe 9 </ b> A, and the refrigerant pipe 9 connecting the accumulator 7 and the compressor 1 is sucked. This is referred to as tube 7A.
Here, a refrigerant circuit is comprised by the compressor 1, the 1st heat exchanger 2, the expansion valve 3, the 2nd heat exchanger 4, the four-way valve 5, the muffler 6, the accumulator 7, and the refrigerant | coolant piping 9, and a refrigerant | coolant circulates.

[Compressor 1]
As shown in FIG. 2, the compressor 1 includes a sealed container 11 in which lubricating oil is stored at the bottom and a mechanism for compressing the refrigerant is mounted, and a compression element 15 that is contained in the sealed container 11 and compresses the refrigerant. An electric element 13 for driving the compression element 15, a rotating shaft 14 connecting the electric element 13 and the compression element 15, and a cup muffler 31 covering the compressed gas discharge portion 15a of the compression element 15 from which the compressed refrigerant is discharged. It is equipped with.

[Sealed container 11]
The hermetic container 11 constitutes the outer shell of the compressor 1. In the sealed container 11, the compression element 15 is fixed in contact with the inner wall of the sealed container 11, and the electric element 13 is fixed in contact with the inner wall of the sealed container 11 on the upper side of the compression element 15.
The closed container 11 is formed with a container discharge port 11a and a suction port 11b which are openings. And the discharge refrigerant | coolant piping 9A which discharges the refrigerant | coolant compressed with the compression element 15 from the inside of the sealed container 11 is connected to the formation position of the container discharge port 11a of the sealed container 11, and the formation position of the suction port 11b of the closed container 11 is connected. The suction pipe 7A for supplying the refrigerant into the sealed container 11 is connected.
A lubricating oil reservoir 12 is formed at the bottom of the sealed container 11 and stores lubricating oil that can reduce sliding friction in the compression element 15. The lubricating oil stored in the lubricating oil reservoir 12 is sucked into the compression element 15 together with the refrigerant and supplied to the sliding portion of the compression element 15 and the like.

[Electric element 13]
The electric element 13 includes a rotor 17 that fixes the rotating shaft 14 and transmits its rotation to the rotating shaft 14, and a stator 16 that is configured by mounting a multiphase winding 21 on a laminated iron core. Yes.
In the electric element 13, the rotor 17 is connected to the rotation shaft 14, and the compression element 15 can be driven via the rotation shaft 14. That is, by supplying power to the stator 16 from a power supply (not shown), the rotor 17 rotates, and this driving force can be transmitted to the compression element 15 via the rotating shaft 14. Thereby, the compression element 15 can drive and can compress a refrigerant | coolant.

The rotor 17 has a rotating shaft 14 connected to the inner periphery of the rotor 17. Further, the rotor 17 is supported by the rotating shaft 14 in a state in which a predetermined facing distance is formed between the outer peripheral surface of the rotor 17 and the inner surface of the stator 16.
The stator 16 rotates the rotor 17, and includes, for example, an iron core 19 in which a plurality of oil return holes 18 are formed, a plurality of phases of windings 21, and the like. The stator 16 is provided with its outer peripheral surface fixed to the wall portion (inner peripheral surface) of the sealed container 11.
A predetermined interval is formed between the stator 16 and the rotor 17. For this reason, the high-temperature and high-pressure refrigerant released from the compression element 15 is supplied to the space on the side to which the discharge refrigerant pipe 9 </ b> A in the sealed container 11 is connected via this interval and the like.

[Compression element 15]
The compression element 15 compresses the refrigerant sucked into the sealed container 11, and various mechanisms (for example, a rotary type, a scroll type, a vane type, etc.) can be adopted. In the compressor according to the first embodiment of the present invention, a case where the compression element 15 is a rotary type will be described as an example.
The compression element 15 includes a cylinder 24, a roller 26 connected to the rotary shaft 14 and rotatably provided in the cylinder 24, and a vane 27 that contacts the roller 26 and separates the cylinder 24. Further, the compression element 15 includes an upper bearing portion 28 and a lower bearing portion 29 that close the opening of the cylinder 24 and rotatably support the rotary shaft 14, and a cup muffler 31 that is attached to the upper bearing portion 28. Yes.

  The cylinder 24 has openings at the top and the bottom, and is closed by an upper bearing portion 28 and a lower bearing portion 29. That is, an upper bearing portion 28 that rotatably supports the rotating shaft 14 is provided on the upper side of the cylinder 24, and closes an upper end surface (end surface on the electric element 13 side) of the cylinder 24. Further, a lower bearing portion 29 that rotatably supports the rotating shaft 14 is provided on the lower side of the cylinder 24 and closes the lower end surface (end surface on the lubricating oil reservoir 12 side) of the cylinder 24. .

The roller 26 is connected to the rotating shaft 14, and also rotates with the rotation of the rotating shaft 14, so that the refrigerant supplied into the cylinder 24 can be compressed.
The vane 27 divides the inside of the cylinder 24 in contact with the roller 26, reciprocates in a groove (not shown) formed in the cylinder 24, and the tip is in contact with the roller 26.
The cylinder 24, the roller 26, the vane 27, and the like form a compression chamber that is a space in which the refrigerant is compressed. This compression chamber becomes smaller as the roller 26 and the vane 27 rotate, and the refrigerant supplied to the compression chamber is compressed.

  A compressed gas discharge portion 15 a for discharging the refrigerant compressed by the compression element 15 is formed on the upper bearing portion 28 of the compression element 15. This compressed gas discharge part 15a is a through-hole, and the compressed gas discharge part 15a is provided with a discharge valve 30 that opens the compressed gas discharge part 15a when the pressure in the cylinder 24 becomes equal to or higher than a preset pressure. Yes.

[Rotating shaft 14]
The rotary shaft 14 has an upper end connected to the rotor 17 of the electric element 13 and a lower end supported rotatably on the upper bearing portion 28 and the lower bearing portion 29 of the compression element 15. The rotating shaft 14 rotates about an axis parallel to the vertical direction, and can rotate the roller 26 of the compression element 15. The rotating shaft 14 has an eccentric portion 25 that eccentrically moves the roller 26, and the eccentric portion 25 and the roller 26 are connected to each other.

[Cup muffler 31]
The cup muffler 31 is provided above the compressed gas discharge part 15a so as to cover the compressed gas discharge part 15a. That is, the refrigerant compressed by the compression element 15 and discharged from the compressed gas discharge part 15a is once discharged into the space in the cup muffler 31, and then discharged into the sealed container 11 from the cup muffler discharge port 34 of the cup muffler 31. Is done. Thereafter, the refrigerant is discharged to the outside of the compressor 1 through a discharge refrigerant pipe 9 </ b> A connected to the container discharge port 11 a of the sealed container 11.

[Oxidation heating element 61]
As shown in FIG. 3 and FIG. 2, the oxidation heating element 61, which is a ignited material, is included in the air permeable member 62 a, and the air permeable member 62 a is disposed on the compressed gas discharge part 15 a side of the cup muffler 31 by the air permeable fixing member 62 b. Installed by fixing. The oxidation heating element 61 that is an ignition material is a heat generating material that generates heat by reacting with oxygen in the air mixed in the compressed gas discharged from the compressed gas discharge portion 15a. The oxidation heating element 61 assists the start of ignition or combustion of the flammable refrigerant or the lubricating oil by oxygen in the air mixed in the compressed gas discharged from the compressed gas discharge portion 15a. The oxidation heating element 61 that is an ignition product is installed in a powder state. In addition, you may install the oxidation heat generating body 61 so that it may be located in the space between the cup muffler 31 and the compressed gas discharge part 15a.

  FIG. 4: is the top view (a) of the other cup muffler of the compressor by Embodiment 1 of this invention, and its XX direction sectional drawing (b). 5A is a plan view of another cup muffler of the compressor according to the first embodiment of the present invention, and FIG. As shown in FIG. 4, the oxidation heating element 61 a may be installed on the opposite side to the compressed gas discharge portion 15 a in a state where it is in contact with the cup muffler 31. Further, as shown in FIG. 5, the oxidation heating element 61 and the oxidation heating element 61 a are both on the compressed gas discharge part 15 a side of the cup muffler 31 and on the opposite side to the compressed gas discharge part 15 a in contact with the cup muffler 31. May be installed. 4 and 5, the oxidation heating element 61a, the breathable member 62c, and the breathable fixing member 62d differ from the oxidation heating element 61, the breathable member 62a, and the breathable fixing member 62b only in installation positions. The description is omitted because it is the same.

The oxidation heating element 61 is iron powder, preferably iron powder having a particle size of 100 μm or less, the air-permeable member 62a is a breathable bag, and the air-permeable fixing member 62b is, for example, punching metal.
Here, the air-permeable member 62a is made of glass, PTFE (polytetrafluoroethylene), polyimide, PPS (polyphenylene sulfide) which is a heat-resistant material at a temperature higher than the operating temperature of the compressor, specifically about 200 ° C. or higher. ), A breathable bag made of fibers of polyester, silica, alumina, or the like.

  At the time of manufacturing the compressor 1, in order to prevent the oxidation heating element 61 from touching air and generating heat, iron powder that is the oxidation heating element 61 and lubricating oil are mixed and covered so that the iron powder is covered with the lubricating oil. This prevents the oxidation heating element 61 from reacting with oxygen in the air to generate heat. The lubricating oil covering the iron powder as the oxidation heating element 61 is compressed by the compressor 1 and becomes high temperature and high pressure when air is sucked into the refrigerant circuit constituting the refrigeration cycle of the refrigerator 100 by the operation of the compressor 1. Therefore, the oxidation heating element 61 becomes high temperature, the lubricating oil covering the surface is evaporated and removed, and reacts with the oxygen in the sucked air to generate heat.

  Further, when the oxidation heating element 61 is installed in the compressor 1 in order to prevent the oxidation heating element 61 from touching air and generating heat during manufacture, it is installed in a nitrogen atmosphere without oxygen. Alternatively, in order to prevent heat generation by touching sufficient air, the oxidation heating element 61, which is not shown, but stored in a sealed container is taken out and installed in the compressor 1 to assemble the compressor. The compressor may be sealed so as not to be mixed.

[First heat exchanger 2]
Returning to FIG. 1, the first heat exchanger 2 functions as an evaporator when the refrigerator 100 is performing a heating operation, and when the refrigerator 100 is performing a cooling operation, the first heat exchanger 2 is a condenser (a radiator). ).
The 1st heat exchanger 2 is good to comprise a plate fin and tube type heat exchanger which has a fin provided in parallel and a tube connected to this fin, for example. Although not shown, the first heat exchanger 2 is provided with a blower fan used to promote heat exchange between the refrigerant supplied to the first heat exchanger 2 and air. May be.

[Expansion valve 3]
The expansion valve 3 decompresses and expands the refrigerant, and one is connected to the first heat exchanger 2 and the other is connected to the second heat exchanger 4. Note that the expansion valve 3 may be constituted by, for example, an electronic expansion valve whose opening degree is variable, or a capillary tube.

[Second heat exchanger 4]
One of the second heat exchangers 4 is connected to the four-way valve 5, the other is connected to the expansion valve 3, and heat is exchanged between the refrigerant supplied to the second heat exchanger 4 and the air. It is. When the refrigerator 100 is performing the heating operation, the second heat exchanger 4 functions as a condenser, and when the refrigerator 100 is performing the cooling operation, the second heat exchanger 4 functions as an evaporator.
Similarly to the first heat exchanger 2, the second heat exchanger 4 is constituted by, for example, a plate fin and tube heat exchanger having a plurality of fins provided in parallel and a tube connected to the fins. Good. Moreover, although illustration is abbreviate | omitted to the 2nd heat exchanger 4, heat exchange with the refrigerant | coolant and air which are supplied to the 1st heat exchanger 2 is accelerated | stimulated, and air-conditioning object space (for example, indoor, building, A blower fan used to supply air to a warehouse or the like may be attached.

[Four-way valve 5]
The four-way valve 5 switches the flow path of the refrigerant discharged from the compressor 1 to a flow path where the refrigerant flows into the first heat exchanger 2 or a flow path where the refrigerant flows into the second heat exchanger 4. It is. For example, when the refrigerator 100 performs the heating operation, the four-way valve 5 is switched so as to supply the refrigerant discharged from the compressor 1 to the second heat exchanger 4.

[Muffler 6]
The muffler 6 is provided in the discharge refrigerant pipe 9 </ b> A and reduces pulsation of the refrigerant discharged from the compressor 1. The muffler 6 has an upstream side in the refrigerant flow direction connected to the discharge side of the compressor 1 and a downstream side in the refrigerant flow direction connected to the four-way valve 5.

[Accumulator 7]
The accumulator 7 is connected to a refrigerant pipe 9 between the four-way valve 5 and the compressor 1, and separates the refrigerant flowing out from the second heat exchanger 4 into a liquid refrigerant and a vapor refrigerant, This suppresses inhalation of the liquid refrigerant.

[Description of operation]
Operation | movement at the time of air_conditionaing | cooling operation | movement of the refrigerator 100 which has the compressor 1 comprised in this way is demonstrated.
The refrigerant compressed by the compressor 1 is discharged to the discharge refrigerant pipe 9 </ b> A and flows into the first heat exchanger 2 after passing through the muffler 6. This refrigerant is condensed in the first heat exchanger 2, decompressed by the expansion valve 3, and evaporated in the second heat exchanger 4. The evaporated refrigerant returns to the compressor 1 through the accumulator 7 and circulates in the refrigerant circuit of the refrigerator 100. By such an operation, the cold heat generated by the second heat exchanger 4 can be used for cooling the air-conditioning target space, for example.

During the operation of the compressor 1, the pressure in the refrigerant circuit of the refrigerator 100 is such that the pressure from the compressor 1 to the inlet of the expansion valve 3 becomes a positive pressure higher than the atmospheric pressure, and the pressure of the compressor 1 is increased from the outlet of the expansion valve 3. The pressure to the suction port 11b is a negative pressure lower than the atmospheric pressure.
Therefore, if the refrigerant pipe 9 serving as the refrigerant flow path from the outlet of the expansion valve 3 to the suction port 11b of the compressor 1 is perforated due to corrosion, poor welding, etc., the refrigerant of the refrigerator 100 Air is drawn into the circuit.
Further, for example, the connection position between the refrigerant pipe 9 and the second heat exchanger 4 is deviated from a preset position due to an artificial cause such as assembly, installation, and removal of the refrigerator 100. There is a case. In such a case, air may be sucked into the refrigerant circuit constituting the refrigeration cycle of the refrigerator 100 by the operation of the compressor 1.

In the compressor 1 that employs lubricating oil and further a flammable refrigerant, the air sucked into the compressor 1 is mixed with lubricating oil vapor, mist, etc. to form a flammable mixture. Or mixed with a flammable refrigerant to form a flammable mixture.
Here, the combustible range of isobutane is 1.8 vol% to 8.4 vol% in the atmospheric pressure state, the combustible range of propane is 2.1 vol% to 9.5 vol% in the atmospheric pressure state, and the combustible range of R32 The range is 13.3 vol% to 29.3 vol% at atmospheric pressure.
Further, since the lubricating oil used in the compressor 1 is in the state of vapor and mist inside the compressor 1, even if there is no flammable refrigerant, the lubricating oil vapor and mist are combustible when mixed with air. A sex mixture is formed.

  When the combustible air-fuel mixture formed in this way increases in pressure and temperature due to operation of the compressor 1 and reaches the self-ignition temperature of the lubricating oil or the self-ignition temperature of the refrigerant, it forms in the compressor 1. The combustible air-fuel mixture is ignited. As a result of the applicant's experimental investigation, it has been ascertained that this ignition occurs first at 31 parts of the cup muffler covering the compressed gas discharge part 15 a of the compression element 15 in the compressor 1.

FIG. 6 is an explanatory diagram showing an example of an experimental result of a temperature change of each part in the compressor according to the passage of time during air suction by the operation of the compressor in the compressor according to the first embodiment of the present invention. Specifically, when the compressor 1 is operated and the suction pipe 7A is released to the atmosphere and air is sucked in from the atmosphere, the space above the electric element 13 inside the compressor 1 (the space above the compressor) and the bottom It is the measurement result of the temperature of the discharge valve 30 vicinity (discharge valve) covered with space (compressor lower space) and the cup muffler 31. FIG.
As is clear from this figure, the combustible air-fuel mixture or refrigerant discharged from the discharge valve 30 is the highest temperature in the compressor 1, and therefore, the combustible air-fuel mixture and the cup muffler in and around the cup muffler 31. 31 itself has the highest temperature.

  When the oxidation heating element 61 is installed in a place other than the case where the cup muffler 31 is placed on the compressed gas discharge part 15a side or the side opposite to the compressed gas discharge part 15a in contact with the cup muffler 31, The inside of the cup muffler 31 may become hot earlier than the body 61. In this case, the compressor is not provided with a conventional oxidation heating element, and the effect of installing the oxidation heating element may not be exhibited. Therefore, in the compressor 1, the oxidation heating element 61 that generates heat by reacting with oxygen in the air is installed on the compressed gas discharge portion 15 a side of the cup muffler 31 that reaches the highest temperature first or hits the cup muffler 31. Installed on the opposite side of the compressed gas discharge part 15a in contact with the compressed gas discharge part 15a or on the opposite side of the compressed gas discharge part 15a in contact with the cup muffler 31. Is. Although FIG. 3 has shown and demonstrated the case where the oxidation heat generating body 61 was installed in the compressed gas discharge part 15a side of the cup muffler 31, as shown in FIG. 4, the compressed gas discharge part 15a is in contact with the cup muffler 31. An oxidation heating element 61a may be installed on the opposite side to produce the same effect. Further, as shown in FIG. 5, it may be installed on both the compressed gas discharge part 15a side of the cup muffler 31 and on the opposite side of the compressed gas discharge part 15a in contact with the cup muffler 31. Play.

The self-ignition temperature of the lubricating oil used in the compressor 1 is not generally disclosed. When the applicant examined the self-ignition temperature of the lubricating oil, the lubricating oil mist self-ignited at about 400 ° C. The autoignition temperature of the combustible refrigerant isobutane is 432 to 470 ° C. in the atmospheric pressure state, 430 to 460 ° C. for propane, and 648 ° C. for R32. When the pressure increases, the autoignition temperature decreases accordingly. Although the self-ignition temperature varies depending on the type of the lubricating oil, the lubricating oil may self-ignite at a temperature lower than that of the flammable refrigerant.
For example, when the investigated lubricating oil and the combustible refrigerant having isobutane are employed in the compressor 1, the lubricating oil having the lower self-ignition temperature self-ignites first.

[Oxidation reaction of oxidation heating element 61]
FIG. 7 shows the pressure and temperature of the air-fuel mixture in the compressor and the self-ignition temperature of the lubricating oil over time in the compressor according to Embodiment 1 of the present invention. It is explanatory drawing which showed the relationship with the temperature of an oxidation heat generating body.
In a conventional compressor that does not include the oxidation heating element 61, when air is sucked into the compressor, the internal pressure of the compressor rises and the temperature rises due to the operation of the compressor. On the other hand, as the pressure increases, the self-ignition temperature of the lubricating oil decreases. When the temperature of the air-fuel mixture in the compressor exceeds the self-ignition temperature of the lubricating oil, the air-fuel mixture in the compressor starts to burn.
In the compressor 1 according to Embodiment 1 of the present invention including the oxidation heating element 61, when air is sucked into the compressor 1, the oxidation heating element 61 reacts with oxygen in the sucked air and oxidizes. The temperature rises due to heat generation. The temperature rise of the oxidation heating element 61 is faster than the temperature rise of the air-fuel mixture in the compressor 1, and comes into contact with the oxidation heating element 61 in the cup muffler 31 when the temperature of the oxidation heating element 61 becomes equal to or higher than the self-ignition temperature of the lubricating oil. The air-fuel mixture becomes the starting point of combustion, and the air-fuel mixture in the compressor 1 starts combustion.
As described above, in the compressor 1 according to the first embodiment of the present invention including the oxidation heating element 61, the low pressure before the air-fuel mixture in the compressor 1 reaches the self-ignition temperature of the lubricant and the self-ignition temperature of the refrigerant. Combustion can be started at a low temperature. Therefore, the pressure after combustion can be kept low, and this has the effect of preventing the compressor 1 from being damaged.

[Pressure of compressor 1 before and after combustion]
FIG. 8 is an explanatory diagram showing the relationship between the pre-combustion pressure and the post-combustion pressure of the compressor according to Embodiment 1 of the present invention.
The condition under which the combustible air-fuel mixture in the compressor causes self-ignition is high pressure and high temperature, and the pressure after ignition becomes several times higher than before combustion, exceeds the pressure resistance of the compressor, and the compressor is damaged.
However, the compressor 1 according to the first embodiment of the present invention has the oxidation heating element 61, and when the air is sucked in, the oxidation heat is generated by oxygen in the air. And since it ignites at a lower pressure and lower temperature than the self-ignition of the lubricating oil and the self-ignition of the refrigerant, the pressure after combustion can be kept low, and damage to the compressor 1 can be suppressed.

  As described above, according to the compressor 1 according to Embodiment 1 of the present invention, when air is sucked into the compressor, the compressed gas discharge part side of the cup muffler covering the compressed gas discharge part inside the compressor, or The heating element provided on the opposite side of the compressed gas discharge part in contact with the cup muffler, or on the opposite side of the compressed gas discharge part in contact with the cup muffler and the compressed gas discharge part in contact with the cup muffler It reacts with oxygen in the air and generates heat. Then, the heating element that generates heat by reacting with oxygen ignites the formed combustible mixture while the pressure inside the compressor is not high, thereby increasing the combustion pressure several times the pressure immediately before the explosion. The pressure generated by the explosion can be kept low, and the breakage of the compressor and further the refrigerator can be suppressed.

Embodiment 2. FIG.
FIG. 9: is the top view (a) of the cup muffler of the compressor by Embodiment 2 of this invention, and its YY direction sectional drawing (b). The compressor 1 according to the second embodiment of the present invention is different from the compressor 1 according to the first embodiment of the present invention only in respect of the configuration of the cup muffler 31, and the other configurations are the same.

[Oxidation catalyst 81]
As shown in FIGS. 9 and 2, the oxidation catalyst 81 for the lubricating oil is installed as an ignited material on the compressed gas discharge part 15 a side of the cup muffler 31 by the breathable fixing member 82. The oxidation catalyst 81 that is an ignition product is an oxidation catalyst that promotes a combustion reaction between a combustible refrigerant or lubricating oil and oxygen. The oxidation catalyst 81 assists the start of ignition or combustion of the flammable refrigerant or the lubricating oil by oxygen in the air mixed in the compressed gas discharged from the compressed gas discharge portion 15a. In addition, you may install the oxidation catalyst 81 so that it may be located in the space between the cup muffler 31 and the compressed gas discharge part 15a.

FIG. 10: is the top view (a) of the other cup muffler of the compressor by Embodiment 2 of this invention, and its YY direction sectional drawing (b). FIG. 11: is the top view (a) of another cup muffler of the compressor by Embodiment 2 of this invention, and its YY direction sectional drawing (b).
As shown in FIG. 10, the oxidation catalyst 81a, which is an ignition product, may be installed on the opposite side of the compressed gas discharge part 15a in a state of being in contact with the cup muffler 31. Further, as shown in FIG. 11, the oxidation catalyst 81 and the oxidation catalyst 81a are installed on both the compressed gas discharge part 15a side of the cup muffler 31 and on the opposite side of the compressed gas discharge part 15a in contact with the cup muffler 31. May be. Note that the oxidation catalyst 81a and the air-permeable fixing member 82a shown in FIGS. 10 and 11 are the same as the oxidation catalyst 81 and the air-permeable fixing member 82, and the description thereof will be omitted.

The oxidation catalyst 81 is a material mainly composed of manganese oxide. The oxidation catalyst 81 is MnO ₂ powder, MnO ₂ supported on a metal honeycomb or ceramic honeycomb, heat resistant glass, PTFE (polytetrafluoroethylene), polyimide, PPS (polyphenylene sulfide), polyester, silica. A cloth or a mat made of fiber such as alumina is coated with MnO ₂ powder. The breathable fixing member 82 is, for example, a punching metal. Note that manganese oxide is MnO ₂ is _desired, it may be any of _{MnO 2, Mn 2 O 3,} Mn 3 O 4.

  The powder of the oxidation catalyst 81 is contained in a breathable member, for example, a breathable bag, and the compressed gas discharge unit 15a in the state where the cup muffler 31 is in contact with the compressed gas discharge unit 15a side or in contact with the cup muffler 31. You may install in the state of powder on the other side. Further, the powder of the oxidation catalyst 81 may be installed on both the compressed gas discharge part 15 a side of the cup muffler 31 and the opposite side to the compressed gas discharge part 15 a in a state in contact with the cup muffler 31. Here, as the air-permeable bag, glass, PTFE (polytetrafluoroethylene), which is a material having a heat resistance higher than the maximum temperature when the compressor 1 is operated, specifically about 200 ° C. or higher, It is a breathable bag made of fibers such as polyimide, heat-resistant nylon, PPS (polyphenylene sulfide), silica, and alumina.

FIG. 12 is a diagram showing comparison of lubricating oil decomposition characteristics of MnO ₂ , Mn ₂ O ₃ , Mn ₃ O ₄ , and Ru. Platinum Pt noble metal as an oxidation catalyst, palladium Pd, rhodium Rh, although ruthenium Ru are known, the applicant is _{MnO 2, Mn 2 O 3,} Mn 3 O 4 and the noble metal catalyst is manganese catalyst Ru FIG. 12 shows the results of examining the oxidative decomposition characteristics of the lubricating oil at an atmospheric temperature of 150 ° C.
As can be seen from this figure, air is sucked into the compressor 1 and the formed combustible air-fuel mixture is compressed to a high temperature, and the temperature condition is 150 ° C. lower than the self-ignition temperature. MnO ₂ , Mn ₂ O ₃ It has been found that Mn ₃ O ₄ exhibits excellent characteristics for oxidative decomposition of lubricating oils, and in particular, MnO ₂ exhibits the most excellent oxidative decomposition characteristics.

FIG. 13 is a diagram showing the results of examining the oxidation time course of the lubricating oil with the oxidation catalyst MnO ₂ . As the ambient temperature increases, the oxidation of the lubricating oil by the catalyst is promoted, leading to ignition at 175 ° C., which is lower than the normal oil self-ignition temperature of about 400 ° C., and MnO ₂ is very highly oxidized to the lubricating oil. Has a promoting effect.

[Oxidation reaction of oxidation catalyst 81]
FIG. 14 shows the pressure and temperature of the air-fuel mixture in the compressor and the self-ignition temperature of the lubricating oil over time in the compressor according to the second embodiment of the present invention. It is explanatory drawing which showed the relationship.
In a conventional compressor that does not include the oxidation catalyst 81, when air is sucked into the compressor, the internal pressure of the compressor rises and the temperature rises due to the operation of the compressor. On the other hand, as the pressure increases, the self-ignition temperature of the lubricating oil decreases. When the temperature of the air-fuel mixture in the compressor exceeds the self-ignition temperature of the lubricating oil, the air-fuel mixture in the compressor starts to burn.
In the compressor 1 having the oxidation catalyst 81 according to the second embodiment of the present invention, the self-ignition temperature of the lubricating oil decreases due to the catalytic effect of the oxidation catalyst 81, and the lower pressure and lower temperature than when the oxidation catalyst 81 is not provided. Can start combustion. Therefore, the pressure after combustion can be kept low, and this has the effect of preventing the compressor 1 from being damaged.

[Pressure of compressor 1 before and after combustion]
FIG. 15 is an explanatory diagram showing the relationship between the pre-combustion pressure and the post-combustion pressure of the compressor according to Embodiment 2 of the present invention.
The condition under which the combustible air-fuel mixture in the compressor causes self-ignition is high pressure and high temperature, and the pressure after ignition becomes several times higher than before combustion, exceeds the pressure resistance of the compressor, and the compressor is damaged.
However, in the compressor 1 according to the second embodiment of the present invention, the oxidation catalyst 81 is provided, the self-ignition temperature of the lubricating oil is lowered due to the catalytic effect, and at a lower pressure and lower temperature than when the oxidation catalyst 81 is not provided. Combustion can be started. Therefore, the pressure after combustion can be suppressed low, and damage to the compressor 1 can be suppressed.

FIG. 16: is the top view (a) of the other cup muffler of the compressor by Embodiment 2 of this invention, and its ZZ direction sectional drawing (b). In the description of the compressor according to Embodiment 2 of the present invention, the case where a catalyst in which MnO ₂ is supported on a metal honeycomb, a ceramic honeycomb or the like is used as the oxidation catalyst 81 is shown. However, as shown in FIG. 16, the MnO ₂ catalyst 83 may be supported directly on the metal cup muffler 31, and the same effect is achieved.

FIG. 17: is the top view (a) of the other cup muffler of the compressor by Embodiment 2 of this invention, and its ZZ direction sectional drawing (b). FIG. 18 is a plan view (a) and another ZZ direction sectional view (b) of yet another cup muffler of the compressor according to the second embodiment of the present invention. FIG. 16 shows a case where the MnO ₂ catalyst 83 is supported only on the compressed gas discharge part 15 a side of the metal cup muffler 31. However, as shown in FIG. 17, the MnO ₂ catalyst 83a may be supported only on the side opposite to the compressed gas discharge part 15a, and as shown in FIG. 18, MnO ₂ catalyst 83 and MnO ₂ are disposed on both sides of the cup muffler 31. a _second catalyst 83a may be supported. The MnO ₂ catalyst 83a shown in FIG. 17 and FIG. 18 is the same as the MnO ₂ catalyst 83 shown in FIG.
16 to 18, the MnO ₂ catalyst 83 has been described. However, the supported oxidation catalyst is preferably MnO _2, but is not limited thereto. Any of MnO ₂ , Mn ₂ O ₃ , and Mn ₃ O ₄ can be used. The cup muffler 31 may carry an oxidation catalyst mainly composed of one or more.

Here, a method for supporting the oxidation catalysts MnO ₂ , Mn ₂ O ₃ , and Mn ₃ O ₄ on the cup muffler 31 will be described. The powdered powder of the oxidation catalyst is applied to the cup muffler 31 by mixing the powdered powder of TIO ₂ with water in a weight ratio of, for example, the oxidation catalyst 0.8 and TIO ₂ 0.2, and dried naturally. Later, it is supported by further drying in a high temperature furnace. Alternatively, ceramics such as alumina oxide, for example, may be sprayed on the surface of the cup muffler 31 and adhered thereto as a carrier to carry the oxidation catalyst powder. The above is an example of the method for supporting the oxidation catalyst on the cup muffler 31. The oxidation catalyst MnO ₂ , Mn ₂ O ₃ , or Mn ₃ O ₄ may be supported on the cup muffler 31 by a method other than the above.

  The cup muffler carrying the oxidation catalyst ignites the formed combustible mixture while the pressure inside the compressor does not become high. It can be suppressed and damage to the compressor can be suppressed.

Embodiment 3 FIG.
FIG. 19A is a plan view of a cup muffler of a compressor according to Embodiment 3 of the present invention, and FIG. In the compressor 1 according to the first and second embodiments of the present invention, the case where the oxidation heating element 61 and the oxidation catalyst 81 are used individually as the ignition products is shown. On the other hand, in the compressor according to the third embodiment of the present invention, the ignited material includes the oxidation heating element 61 which is a heating material that generates heat by reacting with oxygen in addition to the oxidation catalyst 81. For example, a mixture of iron powder of the oxidation heating element and the oxidation catalyst MnO ₂ may be installed in the space between the cup muffler 31 and the upper bearing portion 28. Note that FIG. 19 shows a mode in which the oxidation catalyst 81 and the oxidation heating element 61 are installed and fixed as an ignited material on the compressed gas discharge part 15a side of the cup muffler 31. However, like the compressors according to Embodiments 1 and 2 of the present invention, the oxidation catalyst 81 and the oxidation heating element 61 that are ignition products are in contact with the cup muffler 31 and are opposite to the compressed gas discharge unit 15a. May be installed. Further, the oxidation catalyst 81 and the oxidation heating element 61, which are ignition products, are installed on both the compressed gas discharge part 15a side of the cup muffler 31 and on the opposite side of the compressed gas discharge part 15a in contact with the cup muffler 31. May be.

  When air is sucked in, the oxidation heating element 61 generates oxidation heat by oxygen in the air, and the oxidation of the lubricating oil is promoted by the catalytic effect of the oxidation catalyst 81. Due to these synergistic effects, combustion can be started at a lower pressure and a lower temperature than when they are used alone. Therefore, the pressure after combustion can be kept low, and this has the effect of preventing the compressor 1 from being damaged.

Embodiment 4 FIG.
FIG. 20 is an overall configuration diagram of a refrigerator having a compressor according to Embodiment 4 of the present invention. In the compressor 1 according to the first to third embodiments of the present invention, the temperature sensor 90 that detects the temperature of the oxidation heating element 61 or the oxidation catalyst 81 and the control device 91 that controls the compressor are further provided. .
When air is sucked into the compressor 1, the temperature increase rate of the oxidation heating element 61 or the oxidation catalyst 81 becomes larger than that during normal operation. Therefore, the controller 91 stops the operation of the compressor 1 when the temperature increase rate of the oxidation heating element 61 or the oxidation catalyst 81 detected by the temperature sensor 90 becomes a predetermined value T ° C./sec or more. Also good. In this case, it is possible to prevent the compressor from being damaged without causing combustion. Here, the predetermined value T ° C./sec depends on the operating frequency of the compressor and the internal volume of the refrigerator.
When atmospheric air is sucked from the suction pipe 7A with the conventional compressor having neither the oxidation heating element nor the oxidation catalyst shown in FIG. 6, the temperature rise rate in the vicinity of the discharge valve is 0.15 ° C./sec. When air is not inhaled, such a large temperature rise does not occur. For example, the specified value T in this case may be set in a range of 0 <T <0.15.

  Due to the time change of the temperature by the temperature sensor 90 that detects the temperature of the oxidation heating element and oxidation catalyst, the compressor operation is stopped while the flammable mixture formed is not ignited to prevent explosion, and the compressor is damaged. Can be suppressed.

DESCRIPTION OF SYMBOLS 1 Compressor, 2 1st heat exchanger, 3 Expansion valve, 4 Second heat exchanger, 5 Four-way valve, 6 Muffler, 7 Accumulator, 7A Intake pipe, 9 Refrigerant pipe, 9A Discharge refrigerant pipe, 11 Sealed container, 11a Container discharge port, 11b Suction port, 12 Lubricating oil reservoir, 13 Electric element, 14 Rotating shaft, 15 Compression element, 15a Compressed gas discharge part, 16 Stator, 17 Rotor, 18 Oil return hole, 19 Iron core, 21 Winding , 24 Cylinder, 25 Eccentric part, 26 Roller, 27 Vane, 28 Upper bearing part, 29 Lower bearing part, 30 Discharge valve, 31 Cup muffler, 34 Cup muffler discharge port, 61 Oxidation heating element, 61a Oxidation heating element, 62a Ventilation Member 62b Breathable fixing member 62c Breathable member 62d Breathable fixing member 81 Oxidation catalyst 81a Oxidation catalyst 82 Breathable fixing member 82a Breathable fixing member 8 MnO ₂ catalyst, 83a MnO ₂ catalyst, 90 temperature sensor, 91 a control device, 100 refrigerator.

Claims (11)

Covers a compression element that compresses the refrigerant, an electric element that drives the compression element, a rotating shaft that connects the electric element and the compression element, and a compressed gas discharge portion of the compression element that discharges the compressed refrigerant In a compressor having a cup muffler and a hermetically sealed container that contains these and stores lubricating oil at the bottom,
The compressed gas discharge part side of the cup muffler, or
The side opposite to the compressed gas discharge part in contact with the cup muffler, or
On the opposite side of the compressed gas discharge part in the state of being in contact with the compressed gas discharge part side of the cup muffler and the cup muffler,
A compressor in which an ignitable material that assists in ignition or combustion start of a combustible refrigerant or lubricating oil is installed by oxygen in the air mixed in the compressed gas discharged from the compressed gas discharge section.   The compressor according to claim 1, wherein the ignited material is installed in a powder state.   The compressor according to claim 1 or 2, wherein the ignited material is a heat generating material that generates heat by reacting with oxygen.   The compressor according to claim 3, wherein the ignited material is iron powder having a particle size of 100 μm or less.   The compressor according to claim 1 or 2, wherein the ignition product is an oxidization catalyst that promotes a combustion reaction between a combustible refrigerant or the lubricating oil and the oxygen.   The compressor according to claim 5, wherein the oxidation catalyst is a material mainly composed of manganese oxide. The compressor according to claim 6, wherein the manganese oxide is any one of MnO ₂ , Mn ₂ O ₃ , and Mn ₃ O ₄ .   The compressor according to any one of claims 5 to 7, wherein the ignition product includes a heat generating material that generates heat by reacting with oxygen in addition to the oxidation catalyst.   The compressor according to any one of claims 5 to 8, wherein the oxidation catalyst is installed in a state of being supported on a carrier attached to the cup muffler.   The compressor according to any one of claims 1 to 8, wherein the ignited material is installed by being wrapped in a breathable member.   The compressor as described in any one of Claims 1-10 provided with the temperature sensor which measures the temperature of the said ignition matter.

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