JP4784408B2 - Compressor and manufacturing method thereof - Google Patents

Description

  The present invention is used as a compressor in commercial and household air conditioners (air conditioners) and the like, and mainly relates to a sliding member of a scroll compressor.

  An example of a conventional scroll compressor will be described below with reference to the drawings.

  The scroll compressor includes a stationary fixed scroll and a turning scroll that swings while being engaged with the fixed scroll. Here, the compression principle of the scroll compressor is already known and will not be described.

  As shown in FIG. 5, the orbiting scroll 101 is formed on a disc-shaped end plate 102, a wrap portion 104 formed upright in a spiral shape from the upper surface portion 103 of the end plate 102, and a lower portion of the end plate 102. The bearing portion 105 is provided. Conventionally, the orbiting scroll 101 has been manufactured by cutting and finishing the surface of an iron-based cast product. However, in recent years, the orbiting scroll 101 has been installed in order to improve the efficiency of the scroll compressor. As it is required to be driven at a high rotational speed of around 10,000 revolutions per minute, by using an aluminum alloy having a smaller specific gravity than the iron-based material as the forming material of the orbiting scroll 101, There is a demand for increasing the efficiency and weight of scroll compressors.

  Under such circumstances, conventionally, as shown in FIG. 6, the base plate portions 106 and 107 of the end plate 102 and the lap portion 104 are made of an aluminum die made of a material containing 30% silicon, some nickel and magnesium. It is integrally formed as a cast product, and the upper surface portion 103 and the side surface portion 108 (FIG. 5) of the end plate 102 and the surface layer portion 109 of the wrap portion 104 contain the same material as the base material portions 106 and 107, that is, contain 10% or more silicon. An orbiting scroll made of an aluminum alloy powder sintered material has been proposed (see, for example, Patent Document 1).

  The orbiting scroll 101 is formed by die-casting the end plate 102 and the lap portion 104 with the above-described aluminum alloy, and then bonding the surface of the base material portions 106 and 107 of the die-cast product with a powder sintered material of the same material as a binder. It is manufactured through a process of covering with insert molding and sintering after removing the binder.

Since the orbiting scroll 101 configured as described above is lightweight, even the high-speed rotation of about 10,000 rotations per minute causes less damage such as surface pressure on the bearing mechanism and the like, and the base portions 106 and 107 Even if the silicon segregation portion exists, the surface layer portions 103, 108, 109 of the end plate 102 and the lap portion 104 are formed of a powder sintered material in which silicon or the like is uniformly dispersed. , 108 and 109 are also excellent in the finished surface, so that no silicon drop-off portion is formed on the surface as a starting point of fatigue failure, and the surface is highly reliable. Therefore, the scroll compressor equipped with the orbiting scroll 101 can be rotated at a high speed and can be highly efficient, and can be reduced in size and weight.
JP-A-3-242486 (page 4, FIG. 1)

However, in the orbiting scroll 101, the surface layer portions 103, 108, and 109 are formed of a powder sintered body of an aluminum alloy, and the surface layer portions 103, 108, and 109 are formed by insert molding as described above. 106, 107 is formed so as to cover the surface, and then the binder is removed and sintered, so that a partially thin aluminum-rich layer is formed on the outermost surface of the surface layer portions 103, 108, 109. There are the following problems due to the presence of this thin aluminum-rich layer. That is, in the scroll compressor, since the liquid return is severe at the time of excessive operation, particularly at the start of the defrosting operation, a situation where the lubricating oil is temporarily insufficient around the orbiting scroll 101 occurs. Further, the discharge pressure increases as the defrosting progresses. However, since the thrust surface of the orbiting scroll 101 is strongly pressed against the fixed scroll by the increase of the discharge pressure, the oil film is likely to be cut off on the thrust surface. Further, since the defrosting operation is performed at a high speed for the purpose of completing the defrosting in a short time, the temperature of the thrust surface is increased by the frictional heat. Further, during excessive operation such as defrosting, the temperature difference between the suction temperature and the discharge temperature is widened, so that the blade at the center of the orbiting scroll 101 expands greatly and expands, and the tip of the blade is fixed at the fixed scroll. And the lubricating oil is cut off, and the frictional heat associated therewith increases the sliding temperature, further promoting thermal expansion, and the lubrication state becomes more severe.

  As described above, when the lubrication state becomes severe, the adhesion of the outermost thin aluminum-rich layer covering the silicon on the thrust surface of the orbiting scroll 101 to the silicon is low, so that the aluminum-rich layer may peel off. There is a risk of seizure when peeled. Therefore, the scroll compressor provided with the orbiting scroll 101 cannot secure sufficient reliability. The present invention has been made in view of the above-described conventional problems, and achieves high weightlessness and high efficiency by high-speed rotation, and is high in that there is no risk of seizure even during excessive operation where the lubrication state becomes severe. An object of the present invention is to provide a compressor sliding member having reliability.

  In order to solve the conventional problem, the sliding member of the compressor of the present invention is formed of a soft material in which hard particles harder than that are dispersed in a base material, and is harder than the base material at least in the sliding portion. By spraying water containing hard particles with high non-adhesiveness by gas pressure, a small amount of soft material of the sliding part is peeled off, and the exposure rate of the hard material is increased on the outermost surface of the sliding part, A depression that also serves as an oil reservoir is formed on the surface, and a uniform oxide film is formed on the surface of the soft material.

  In such a configuration, the sliding member made of a soft material achieves weight reduction and high efficiency by high-speed rotation, but is appropriately exposed when the lubrication state at the sliding portion becomes severe. Due to the non-adhesiveness of the hard particles, the appropriately formed oil sump, and the oxide film of the soft material itself on the outermost surface, seizure resistance and wear resistance characteristics almost equal to those of the carbon material or the like can be obtained. Therefore, the compressor provided with this sliding member can effectively prevent seizure and wear during excessive operation where the lubrication condition becomes severe, especially during defrosting operation, and even in a large capacity and multiple refrigerant system. It has extremely high reliability with no risk of malfunction.

  According to the sliding member of the compressor of the present invention or the manufacturing method thereof, it is possible to obtain an inexpensive and efficient compressor with a small number of parts by high-reliability and short-time processing. A business-use and home-use air conditioner with excellent consumption efficiency can be obtained.

1st invention and 9th invention are formed from the soft material which disperse | hardened the hard particle | grains harder than it in a base material, and are harder than a base material at least to a sliding part, and hard non-adhesive hard microparticles | fine-particles are carried out. By spraying the contained water by gas pressure, a small amount of the soft material of the sliding part is peeled off, the exposure rate of the hard material is increased on the surface of the sliding part, and a recess that also becomes an oil reservoir is formed on the surface. Further, a uniform oxide film is formed on the surface of the soft material. According to this configuration, while achieving weight reduction and high efficiency by high-speed rotation, it is possible to effectively prevent the occurrence of seizure, and there is a risk that problems may occur even in a large-capacity and multi-refrigerant system. A highly reliable compressor can be obtained, and according to this method, since processing can be performed in a very short time, a compressor that is easy to manufacture and inexpensive can be obtained.

  The second invention uses an aluminum-silicon alloy in which silicon as hard particles is dispersed in aluminum as a base material as a soft material, and an inexpensive sliding member can be obtained.

  In a third invention, the silicon is eutectic silicon or refined primary crystal silicon, the average particle diameter is 2 to 10 μm, the area ratio is 4.7% or more, and the oxygen concentration of aluminum which is a soft material Is set to 2% or more, and extremely excellent anti-baking properties and wear-resistant properties can be obtained.

  In the fourth aspect of the invention, the compressor is a scroll compressor, the sliding member is a turning scroll, and the shape of the turning scroll is smaller than that of a sliding member such as a fixed scroll. While achieving high efficiency, it is possible to manufacture a scroll compressor having high reliability that can effectively prevent occurrence of seizure at low cost.

  In a fifth aspect of the invention, the compressor is a scroll compressor, the sliding member is a fixed scroll, and the occurrence of seizure is effectively prevented while achieving weight reduction and high efficiency by high-speed rotation. In addition to obtaining the effect, the effect of improving the strength of the valve seat of the reed valve can be obtained.

  In the sixth aspect of the invention, the compressor is a scroll compressor, and the sliding member is an Oldham ring, and the occurrence of seizure is effectively prevented while achieving weight reduction and high efficiency by high-speed rotation. In addition to a rotary compressor with a large amount of rotational eccentricity and a reciprocating compressor that converts linear motion into rotational motion, the unbalance amount is small and scrolling is extremely low in vibration. There is an advantage of becoming a compressor.

  In a seventh aspect of the invention, the compressor is a scroll compressor, and the sliding member is a frame integrally provided with a bearing, and seizure occurs while achieving weight reduction and high efficiency by high-speed rotation. In addition to obtaining an effect that is effectively prevented, in particular, in a low-pressure scroll compressor in which a thrust bearing that receives the orbiting scroll is installed in the frame, the thrust bearing is changed by changing a part of the shape of the frame. It can be easily formed integrally with the frame, and there is an advantage that the number of parts can be reduced.

  According to an eighth aspect of the invention, the compressor uses carbon dioxide as a refrigerant and PAG, ether, ester, PAO, alkylbenzene, or mineral oil as a lubricating oil, and includes a natural refrigerant not containing chlorine and a lubricating oil compatible therewith. While the combination does not have a significant effect on the destruction of the ozone layer or the global warming phenomenon, the use of carbon dioxide refrigerant, which is a high-pressure refrigerant, applies extremely high pressure to the orbiting scroll and generates extremely high surface pressure on the end plate. However, by exhibiting moderate lubricity and non-adhesiveness, seizure can be effectively prevented, and high reliability is obtained even in high pressure and high differential pressure conditions, and high pressure with high efficiency. A type scroll compressor is obtained.

  Embodiments of the present invention will be described below with reference to the drawings. In addition, this invention is not limited by this Example.

(Embodiment 1)
FIG. 1 is a partially broken front view showing a scroll compressor configured by applying the present invention to a turning scroll 201. In this scroll compressor, a compression mechanism 203 and a motor unit (not shown) for driving the compression mechanism 203 are housed in an airtight container 202 that forms the outer body of the scroll compressor. The compression mechanism 203 includes a fixed scroll 205 fixed to the frame 204, a turning scroll 201 disposed opposite to the fixed scroll 205, an Oldham ring 206 provided between the frame 204 and the turning scroll 201, and a turning A crankshaft 207 that connects the scroll 201 to the motor unit is provided. The fixed scroll 205 includes an end plate 208, a lap portion 209, a bottom surface 210, and a suction port 211, and a suction pipe 212 is connected to the suction port 211. As shown in FIG. 2, which is a longitudinal sectional view of the orbiting scroll 201, the end plate (thrust surface) 213, (frame side) 214, a lap portion 215, a wrap tip portion 216, a bearing 217, and a key groove 218 are provided. It is configured. The wrap portion 215 of the orbiting scroll 201 and the wrap portion 209 of the fixed scroll 205 are arranged to face each other in a bowl shape and mesh with each other. However, the height of the wrap portion 215 of the orbiting scroll 201 is the same as that of the wrap portion 209 of the fixed scroll 205. It is set slightly lower than the height.

  An annular groove 219 is formed in the frame 204, and a seal member 220 that seals between the frame 204 and the orbiting scroll 201 is provided in the annular groove 219, and the inner side of the seal member 220 with respect to the annular groove 219 has a high pressure. It is set to be. During operation of the compressor, the orbiting scroll 201 is pressed against the fixed scroll 205 by the high pressure, and the gap between the lap tip 216 of the orbiting scroll 201 and the bottom surface 210 of the fixed scroll 205 is sealed with lubricating oil (not shown). The

  Next, a characteristic configuration of the orbiting scroll 201 will be described with reference to FIGS. 3 is a diagram schematically showing a cross-sectional structure of the surface layer portion after processing of the orbiting scroll 201, and FIG. 4 is a diagram schematically showing a cross-sectional structure of the surface layer portion of the orbiting scroll 201 according to Embodiment 1 of the present invention. It is.

  The orbiting scroll 201 is formed by casting or forging using a soft material 223 made of an aluminum-silicon alloy obtained by dispersing fine eutectic silicon 222 as hard particles in aluminum 221 as a soft base material. Has been. The eutectic silicon 222 has an average particle diameter of 2 to 10 μm and is dispersed in the aluminum 221 so that the area ratio is 4.7% or more. Furthermore, the sliding portions in the orbiting scroll 201, that is, the sliding portions such as the end plates 213 and 214, the wrap portion 215, the wrap tip portion 216, the bearing 217, and the key groove 218, are at least partially or over the entire surface. Water containing hard fine particles that are harder than the material and have high non-adhesive properties is sprayed by gas pressure and applied. As shown in FIG. 3, the aluminum 221 covering the surface layer portion of about 1 μm or less after processing is peeled off by a small amount by the water and gas containing the hard particles having high non-adhesion properties, and then slides as shown in FIG. The eutectic silicon 222 remains and is exposed on the surface of the portion, and a fine oil sump 224 is formed on the aluminum 221 as a base material. At this time, since the aluminum 221 which is the base material exposed on the surface is in a pure aluminum state, it is kept in water so that it does not touch the atmosphere, and then is evenly touched to the air, so that the surface of the soft material is even. An oxide film 229 is formed.

Next, the operation of the scroll compressor will be described. The rotation of the motor unit is transmitted to the orbiting scroll 201 via the crankshaft 207 and causes the orbiting scroll 201 to orbit in cooperation with the Oldham ring 206. The wrap portion 215 of the orbiting scroll 201 and the wrap portion 209 of the fixed scroll 205 are arranged oppositely in a bowl shape and mesh with each other, and the refrigerant flows from the suction pipe 212 through the suction port 211 as the orbiting scroll 201 moves. Inhales and compresses this refrigerant. The compressed refrigerant is pushed out of the reed valve 226 from the discharge port 225 and discharged into the sealed container 202, and then led out of the sealed container 202 from the discharge pipe 227. During this operation, the inside of the sealed container 202 is maintained at a high pressure.

  By the way, in the heating operation at a low temperature in the scroll compressor, when the frost is intense, the defrosting operation is forcibly switched. At that time, a severe liquid return occurs and the end plate 213 and the lap portion of the orbiting scroll 201 are moved. 215 and the lubricating oil remaining on the wrap tip 216 are washed away. At this time, in the orbiting scroll 201, each sliding portion (end plate 208, wrap portion 209, end plate 213, wrap portion 215, fixed scroll 205 facing the eutectic silicon 222 exposed on the surface of the wrap tip portion 216 is opposed. And the seizure of the orbiting scroll 201 due to the lack of lubricating oil due to the non-adhesiveness of the eutectic silicon 222 and the oxide film 229 formed on the aluminum 221 as the base material. Moreover, the occurrence of wear is extremely effectively prevented.

  Further, as the defrosting effect is advanced by the defrosting operation, the discharge pressure rises and this high discharge pressure acts on the inside of the seal member 220, so that the orbiting scroll 201 is strongly pressed against the fixed scroll 205. Therefore, a high surface pressure is generated between the end plate 213 of the orbiting scroll 201, the end plate 208 of the fixed scroll 205, the front end 228 of the wrap portion 209, and the bottom surface 210 of the fixed scroll 205. On the other hand, the lubricating oil (not shown) stored in the lower part of the hermetic container 202 is supplied to the compression mechanism 203, but the viscosity greatly decreases due to the effect of liquid return in the defrosting operation. 201 and fixed scroll 205 are in very severe lubrication. However, in addition to the non-adhesiveness of the eutectic silicon 221 exposed on the end plate 213 and the lap part 215 of the orbiting scroll 201 and the oxide film 229 formed on the aluminum 221 as the base material, the aluminum 220 as the base material Occurrence of seizure of the orbiting scroll 201 is extremely effectively prevented by the lubricating oil held in the fine oil sump 223 formed.

  Also, the bearing 217 and the keyway 218 of the orbiting scroll 201 are supplied with lubricating oil whose viscosity has been reduced and the lubrication becomes severe, but the non-adhesiveness of the exposed eutectic silicon 222 and the aluminum 221 as the base material In addition to the oxide film 229 formed on the substrate, the lubricating oil held in the fine oil sump 224 formed on the aluminum 221 as the base material prevents the orbiting scroll 201 from being seized extremely effectively. .

  Therefore, the orbiting scroll 201 is made of a soft material 223, or a forged product, and while achieving weight reduction and high efficiency by high-speed rotation, the occurrence of seizure and wear are extremely effectively prevented. Therefore, extremely high reliability equivalent to carbon or the like can be obtained in the boundary lubrication state.

In particular, in the orbiting scroll 201, the area ratio of the eutectic silicon 222 is set to 4.7% or more, and the oxygen concentration of aluminum as a soft material is set to 2% or more. For the following reason, The occurrence of seizure and wear are reliably prevented. That is, as a result of examining the relationship between the area ratio of the eutectic silicon 222 and the occurrence of seizure / abrasion amount with respect to the oxygen concentration of the aluminum 221 as the base material by the frictional wear / seizure test, the area ratio of the eutectic silicon 222 is When the oxygen concentration of the base material aluminum 221 is set to less than 2% and less than 2%, the test result in the frictional wear and seizure test becomes poor, and the area ratio of the eutectic silicon 222 is 4. When the oxygen concentration of aluminum 221 as the base material was set to 7% or more and 2% or more, the test results in the frictional wear / baking test were good, and the results were comparable to those of carbon. As described above, the area ratio of the eutectic silicon 222 and the oxygen concentration of the aluminum 221 as the base material have a great influence on the occurrence of seizure and wear. It has been found that seizure resistance and wear resistance can be reliably ensured by setting the area ratio of 222 to 4.7% or more and the oxygen concentration of aluminum 221 as a base material to 2% or more.

  In the first embodiment, the orbiting scroll 201 is exemplified as the sliding member. However, instead of the orbiting scroll 201 or in addition to the orbiting scroll 201, the fixed scroll 205 is made of aluminum 221 which is a soft base material. A soft material 223 in which fine eutectic silicon 222, which is hard particles, is dispersed, is cast from an aluminum-silicon alloy, or a forged product, and eutectic silicon 222 has an average particle diameter of 2 to 10 μm. The area ratio is set to 4.7% or more, and the oxygen concentration of the aluminum 221 as the base material is set to 2% or more. In addition to the end plate 208, the wrap portion 209, and the wrap tip portion 228 which are sliding portions of the fixed scroll 205 In each part such as a valve seat of the reed valve 226, it is harder than at least the base material locally or over the entire surface, The containing high cohesiveness hard particles of water, against by injection by the gas pressure, after water retention, by performing a process of exposing uniformly the atmosphere, it is possible to obtain the same effect as described above. Furthermore, the effect of improving the strength of the valve seat is also obtained by the exposed eutectic silicon 222 and the oxide film 229 of the aluminum 221 as the base material.

  Further, in place of or in addition to the orbiting scroll 201, the Oldham ring 206 is made of aluminum as a soft material 223 in which fine eutectic silicon 222 that is hard particles is dispersed in aluminum 221 that is a soft base material. -Consists of a cast or forged product made of a silicon-based alloy, the eutectic silicon 222 has an average particle diameter of 2 to 10 μm, the area ratio is 4.7% or more, and the oxygen concentration of the aluminum 221 as the base material is 2 % Or more, and the key that is the sliding part of the Oldham ring 206 is sprayed with water containing at least hard particles that are harder than the base material and have high non-adhesive properties by gas pressure. In addition to obtaining the same effect as described above by applying the treatment to uniformly contact the atmosphere, the rotation eccentricity is large. Compared to the reciprocating type compressor that converts Tali compressor and linear motion to rotary motion, there is an advantage that an extremely low-vibration scroll compressor unbalance amount becomes smaller. Further, instead of or in addition to the orbiting scroll 201, the frame 204 is made of aluminum-silicon as a soft material 223 in which fine eutectic silicon 222 as hard particles is dispersed in aluminum 221 of a soft base material. Made of a cast alloy or a forged product, an eutectic silicon 222 having an average particle diameter of 2 to 10 μm, an area ratio of 4.7% or more, and an oxygen concentration of aluminum 221 as a base material of 2% or more In addition, the bearing, which is the sliding part, is sprayed with water containing hard fine particles that are harder than the base material and have high non-adhesive properties by spraying with gas pressure. In addition to obtaining the same effects as described above, the thrust bearing that receives the orbiting scroll 201 can be In the low pressure type scroll compressor which is installed in 204, it becomes possible to integrally form the thrust bearing to the frame 204 by changing the part shape of the frame 204, there is an advantage that the number of parts can be reduced.

  In addition, scroll compressors that use carbon dioxide as the refrigerant and PAG as the lubricating oil have a significant impact on the destruction of the ozone layer and global warming due to the combination of a natural refrigerant that does not contain chlorine and a lubricating oil that is compatible with it. Because it is not, it is installed in the hot water supply system. However, since the carbon dioxide refrigerant is a high-pressure refrigerant, a particularly high pressure is applied to the orbiting scroll 201 and a very high surface pressure is generated on the end plate 213, and the lubrication state becomes severe. 222 and the oxide film 229 formed on the base aluminum 221 and the fine oil sump 224 effectively prevent seizure and wear, so that even under high pressure and high differential pressure conditions, Not only high reliability can be obtained, but also a low-cost and high-efficiency high-pressure scroll compressor for carbon dioxide can be obtained. Note that the same effect as described above can be obtained when ether, ester, PAO, alkylbenzene, or mineral oil is used as the lubricating oil suitable for the carbon dioxide refrigerant.

  As described above, since the sliding member of the compressor according to the present invention or the manufacturing method thereof has high reliability, it is possible to obtain a low-cost and efficient compressor with a small number of parts. Excellent air-conditioner for business use and home use, etc., and with the same structure, a general bearing bushing material regardless of the compression mechanism, for example, a rotary compressor member or a compressor. The present invention can be similarly applied to a sliding portion that is in a very severe lubrication state beyond the boundary lubrication region during actual operation such as the use of the surface configuration.

Front view of a scroll compressor to which the sliding member of the present invention is applied Vertical sectional view of the orbiting scroll of the present invention Schematic diagram showing the cross-sectional structure of the surface layer of the orbiting scroll after processing The schematic diagram which shows the cross-sectional structure | tissue of the surface layer part of the turning scroll of this invention The perspective view which shows the external appearance of the conventional turning scroll Partial sectional view showing a conventional orbiting scroll

Explanation of symbols

101 Conventional orbiting scroll 102 Conventional orbiting scroll / end plate 103 Conventional orbiting scroll / end plate upper surface portion 104 Conventional orbiting scroll / lap portion 105 Conventional orbiting scroll / bearing portion 106 Conventional orbiting scroll / lap base portion 107 Conventional Orbiting scroll / lap base material part 108 Conventional orbiting scroll / end plate side part 109 Conventional orbiting scroll / lap surface layer part 201 Orbiting scroll 202 Sealed container 203 Compression mechanism part 204 Frame 205 Fixed scroll 206 in one embodiment of the present invention 206 Oldham ring 207 Crankshaft 208 Fixed scroll / end plate 209 Fixed scroll / lap section 210 Fixed scroll / bottom surface 211 Intake port 212 Intake pipe 213 Orbiting scroll / end plate (thrust surface)
214 Orbiting scroll / end panel (frame side)
215 orbiting scroll / lap portion 216 orbiting scroll / lap tip 217 orbiting scroll / bearing 218 orbiting scroll / key groove 219 frame / annular groove 220 seal member 221 aluminum 222 eutectic silicon 223 soft material (aluminum-silicon alloy)
224 Oil sump 225 Discharge port 226 Reed valve 227 Discharge pipe 228 Fixed scroll wrap tip 229 Oxide film

Claims (2)

By spraying water containing hard fine particles that are formed of a soft material in which hard particles harder than that are dispersed in a base material, harder than at least the base material, and have high non-adhesive properties in the sliding portion, by gas pressure, A small amount of the soft material on the sliding part is peeled off, the exposure rate of the hard material is increased on the outermost surface of the sliding part, a recess that becomes an oil reservoir is formed on the surface, and a uniform oxide film is formed on the surface of the soft material. A formed compressor ,
The oxide film is formed by peeling off a small amount of the soft material of the sliding portion, holding the solution in water, and then contacting the air evenly with the air. The compressor according to claim 1, wherein the soft material is an aluminum-silicon alloy in which silicon as hard particles is dispersed in aluminum as a base material.

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