JP2012154185A - Rotary compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase the efficiency of a compressor by restraining strength from being decreased by a hole serving as an oil feeding passage provided in a crankshaft and a hole serving as a channel for refrigerant gas foamed in the oil feeding passage.SOLUTION: The length of the hole serving as the oil feeding passage provided in the axial direction of the crankshaft is set equal to/shorter than that of a lower end of a bearing of a closing member, and the closing member has a gas channel that brings the oil feeding passage and the inside of an airtight container into a conduction state.

Description

  The present invention relates to a rotary compressor that compresses refrigerant gas such as a refrigeration air conditioning system.

  In recent years, it has become necessary to apply natural refrigerants and further increase the efficiency of compressors from the viewpoint of reducing environmental impact. For example, in a refrigeration and air conditioning system using a carbon dioxide refrigerant among natural refrigerants, the differential pressure between the discharge pressure and the suction pressure with respect to the R410A refrigerant increases, so the load on each component constituting the compression mechanism section increases. . Therefore, how to reduce the deformation in the compression mechanism part allowed in the prior art and suppress the mechanical loss is a big problem.

  2. Description of the Related Art A rotary compressor that compresses refrigerant gas, such as a refrigeration and air conditioning system, is provided with a crankshaft that transmits rotational torque of an electric motor unit housed in a hermetic container of the compressor to a compression mechanism unit. The crankshaft needs to have strength against two loads. The two loads are a load that works in the radial direction due to the rotational torque and magnetic attraction generated in the motor part, a gas compression torque in the compression mechanism part that acts in the opposite direction to the rotational torque generated in the motor part, and mainly This is a load that acts on the bearing portion that holds the crankshaft.

  On the other hand, the crankshaft is provided with a hole serving as an oil supply passage in the axial direction from the lower end in order to supply the refrigerating machine oil stored in the lower part of the sealed container of the compressor to the compression mechanism. The crankshaft is provided with a gas flow path in the direction of extending the hole serving as the oil supply path, for example, as disclosed in Patent Document 1, in order to prevent oil supply obstruction due to the foaming phenomenon of the refrigerant gas dissolved in the refrigerating machine oil. It has been.

JP 2008-208752 A

  The diameter of the crankshaft must be large enough to provide the oil supply passage and the gas passage and to have strength against torque and load generated in the electric motor portion and the compression mechanism portion. However, if the shaft diameter of the crankshaft is increased, the frictional force in the bearing portion increases and mechanical loss occurs. Here, it is indispensable to provide the hole serving as the oil supply passage in the axial direction of the crankshaft in order to supply the refrigerating machine oil to each sliding portion in the compression mechanism section. Therefore, the hole serving as the oil supply passage needs to have a minimum axial length in consideration of the strength of the crankshaft. On the other hand, the gas flow path needs to be electrically connected to the oil supply path and the inside of the sealed container, but is not necessarily provided in the axial direction of the crankshaft.

  In Patent Document 1, the oil supply passage is opened from the lower end to the vicinity of the center of the upper bearing in the axial direction of the crankshaft. Further, the gas flow path is opened to the vicinity of the lower end of the electric motor section so as to extend the oil supply path after reducing the diameter with respect to the inner diameter of the oil supply path, and then toward the radial direction of the crankshaft. Opened. According to this, the portion of the crankshaft that engages with the electric motor portion is a solid shaft, so the strength is increased. However, since the portion of the crankshaft that covers the upper bearing portion is a hollow shaft, the strength is low. Therefore, in the hollow shaft of the crankshaft, the portion of the crankshaft that covers the upper bearing portion is deformed by the torque and load, and the frictional force with the upper bearing portion may increase, leading to a reduction in compressor efficiency. It was.

  An object of the present invention is to improve the efficiency of a compressor.

The purpose of the present invention is to
A motor part is housed in a sealed container, a crankshaft having an eccentric part for transmitting the rotation of the motor part, and a compression mechanism part for performing compression work by the rotational power of the crankshaft are provided, and the compression mechanism part is a cylinder A roller disposed in the cylinder and rotationally driven by an eccentric part of a crankshaft; a vane extending to the outer periphery of the roller and entering and exiting a storage part provided in the cylinder according to the eccentric movement of the roller; It is constituted by a closing member having a bearing portion that closes both end surfaces of the cylinder and holds the crankshaft, and stores refrigerating machine oil that lubricates the compression mechanism portion in the lower part of the hermetic container,
A hole serving as an oil supply path for the refrigerating machine oil is provided in the axial direction from the lower end of the crankshaft, and a hole serving as a flow path for the refrigerant gas that is communicated between the oil supply path and the sealed container and foamed in the oil supply path is provided. In the rotary compressor
The length of a hole serving as an oil supply path provided in the axial direction of the crankshaft is set to be equal to or less than the lower end of the bearing portion of the upper closing member, and a gas flow path that conducts the oil supply path and the inside of the sealed container is closed on the upper side. This is achieved by having the member substantially in the radial direction of the crankshaft.

The object of the present invention is to
Take the support of the crankshaft with the upper bearer having the upper bearer plane part for fixing in the sealed container,
Compressing the refrigerant by changing the volume of the compression chamber disposed in the cylinder by the rotation of the crankshaft,
In the rotary compressor that sucks up the oil in the hermetic container by the oil supply passage disposed in the crankshaft and supplies the oil to the compression chamber and its surroundings,
The crankshaft is an oil supply passage through which oil passes, and is disposed up to the position of the crankshaft that penetrates the thickness of the cylinder and corresponds to the upper bearer plane part, and is connected to the upper bearer bearing part. An oil supply passage that does not reach the position of the corresponding crankshaft and keeps the corresponding crankshaft solid;
In the upper bare plane portion, a gas flow path for discharging a refrigerant from the compression chamber to the sealed container is disposed.
This is achieved by a rotary compressor characterized in that.

  According to the present invention, the efficiency can be improved.

The longitudinal cross-sectional view of the rotary compressor regarding this invention. The longitudinal cross-sectional view of the compressor in a prior art. Sectional drawing showing the flow of the refrigerating machine oil and refrigerant gas regarding this invention. Sectional drawing showing the flow of the refrigeration oil and refrigerant gas regarding a prior art.

  Embodiments will be described below with reference to the drawings.

  A crankshaft 2 having an eccentric portion for transmitting the rotation of an electric motor portion is provided in a sealed container 1 serving as a compressor case, and a compression mechanism portion for performing a compression work by the rotational power of the crankshaft 2, and the compression mechanism portion Includes a cylinder 3, a roller 4 disposed in the cylinder 3 and driven to rotate by an eccentric portion 2 a of the crankshaft 2, and extends to the outer periphery of the roller 4 so as to respond to the eccentric motion of the roller 4. A vane 5 that goes in and out of a storage portion provided; an upper bear 6 having a bearing portion that closes the upper end surface of the cylinder 3 and holds the crankshaft 2; and a lower end surface of the cylinder 3 that closes the lower end surface and the crank The lower bear 7 has a bearing portion for holding the shaft 2.

  The upper bear 6 includes an upper bear bearing portion 6b and an upper bear flat portion 6e as main components. The upper bear plane portion 6 e is fixed to the sealed container 1, whereby the upper bear 6 is fixed to the sealed container 1. Therefore, the upper bare plane portion 6e has a certain axial length (thickness).

  Refrigerating machine oil 8 that lubricates the compression mechanism is stored in the lower part of the sealed container 1. The compressor constitutes a part of the refrigeration cycle apparatus. Refrigerant gas flowing into the compressor from the refrigeration cycle flows into the cylinder 3 from the suction port 9 provided in the cylinder 3 in the compression mechanism, and the cylinder inner wall surface 3a, the roller outer wall surface 4a, and the vane side surface. Then, the pressure is increased in the compression chamber 10 formed by the upper bearer inner wall surface 6a and the lower bearer inner wall surface 7a, and discharged from the discharge port (not shown) into the sealed container 1.

  The refrigerating machine oil 8 is sucked up from an oil supply passage 2b having a diameter d1 provided in the axial direction of the crankshaft 2 and 2c serving as a supply passage from the oil supply passage 2b to the lower bare bearing portion 7b, and the oil supply passage. 2b is supplied to each sliding portion from 2d serving as a supply path to the eccentric part 2a of the crankshaft and the roller inner wall surface 4b, and from a supply path 2e from the oil supply path 2b to the upper bearer bearing part 6b.

  On the outlet side of the three supply passages 2c, 2d, 2e, a space 12 for improving the inflow property of the refrigerating machine oil is provided. The upper bear bearing portion 6b and the lower bear bearing portion 7b are provided with grooves 6c and 7c (oblique broken lines in the figure), respectively, and utilize the rotational motion of the crankshaft 2 and the viscosity of the refrigerator oil 8 Oil is supplied by a viscous pump mechanism. 3 and 4 indicate the flow of the refrigerating machine oil 8.

  Here, the refrigerant gas discharged from the discharge port is liquefied and dissolved in the refrigerating machine oil 8. The refrigerant dissolved in the refrigerating machine oil 8 is vaporized when the ambient temperature is increased or depressurized, and the volume is increased to generate a foaming phenomenon. For this reason, the oil supply passage 2b is provided with a gas flow path for preventing oil supply obstruction due to the foaming phenomenon. 3 and 4 indicate the flow after the refrigerant dissolved in the refrigerating machine oil 8 is vaporized.

  Hereinafter, the prior art will be described with reference to FIG. 2 to clarify the problem of the present invention. The oil supply passage 2b has a diameter d1 and a length in the axial direction of the crankshaft 2 from the lower end of the crankshaft 2 to the approximate center of the upper bearer bearing portion 6b. Further, a hole 2f formed with a diameter d2 from the upper end surface of the oil supply passage 2b to the upper end of the crankshaft 2 in the axial direction of the crankshaft 2 connects the oil supply passage 2b and the inside of the sealed container 1 with each other. This is a gas flow path for preventing an oil supply hindrance due to a foaming phenomenon in the oil supply path 2b. Therefore, the crankshaft 2 is a hollow shaft in the entire length from the lower end to the upper end by the oil supply passage 2b and the gas passage 2f.

Here, since the crankshaft 2 transmits the rotational force of the electric motor part and is held by the upper bearer bearing part 6b, strength against torque and bending force is required. Particularly in the upper bearer bearing portion 6b,
The peripheral speed determined by the diameter D1 of the crankshaft 2 and the rotational speed of the compressor,
A vertical load from the crankshaft 2 to the upper bearing portion 6b,
Friction coefficient determined by the surface properties of the crankshaft 2 and the upper bare bearing portion 6b,
The frictional force represented by the product of these three elements works to generate mechanical loss.

  Of the three factors that determine the frictional force, the vertical load increases as the deformation of the crankshaft 2 increases. On the other hand, the peripheral speed of the crankshaft 2 among the three factors that determine the frictional force increases as the diameter D1 of the crankshaft 2 increases.

  For this reason, in order to reduce the mechanical loss caused by the frictional force, it is necessary to suppress the deformation of the crankshaft 2 or to reduce the peripheral speed of the bearing portion of the crankshaft 2. The recent usage environment of compressors, for example, when installed in a room air conditioner for home use, requires increasing the number of revolutions or expanding the cylinder volume of the compressor for the purpose of improving the heating capacity. The deformation or peripheral speed is inevitably large.

  In addition, the refrigerant gas generated by the foaming phenomenon and a part of the refrigerating machine oil 8 that has passed through the oil supply path 2b flow through the gas flow path 2f. Here, it is desirable that the refrigerating machine oil 8 stays in the lower part of the hermetic container 1 in order to stably supply the sliding parts of the compressor, but a part of the compressor oil 8 flows together with the flow of the refrigerant gas. It will flow out to the external refrigeration cycle.

  When the amount of the refrigerating machine oil 8 flowing out to the refrigeration cycle becomes excessive, the efficiency decreases due to an increase in flow path resistance and a decrease in heat exchange efficiency in the refrigeration cycle. Due to the recent changes in the compressor usage environment as described above, the amount of refrigerant gas circulated also increases. Therefore, it is required to reduce the amount of refrigerant oil 8 flowing out to the refrigeration cycle.

  In such a background, in the crankshaft 2 that has become a hollow shaft by the oil supply passage 2b and the gas flow passage 2f as in the prior art, the lack of strength particularly in the upper bare bearing portion and the refrigerating machine oil 8 is caused by the gas flow passage 2f. It has been a problem to suppress the efficiency reduction caused by passing through the motor part and flowing out to the refrigeration cycle.

  In the following, the embodiment of the present invention will be described with reference to FIG.

  The oil supply path 2b has a diameter d1 and a length in the axial direction of the crankshaft 2 from the lower end of the crankshaft 2 to the lower end of the upper bare bearing portion 6b. The gas flow path 2 f is provided in the closed portion of the upper bear 6 in the radial direction of the crankshaft 2. With the above configuration, it is possible to solve the above-described two problems in the prior art, mechanical loss due to frictional force, and efficiency reduction due to the outflow of oil to the refrigeration cycle.

  First, reduction of mechanical loss in the bearing portion of the crankshaft 2 which is the first problem will be described. The oil supply path 2b needs to be electrically connected to the three supply paths 2c, 2d, and 2e in order to supply the refrigerating machine oil 8 to each sliding portion. Therefore, the length of the oil supply path needs to be provided so as to reach the upper bare supply path 2e that is the uppermost of the three supply paths 2c, 2d, and 2e. Since the space 12 is provided in the vicinity of the outlet of the upper bare oil supply passage 2e, it is not a bearing mechanism. From the above, the crankshaft 2 has a solid portion increased by making the length of the oil supply passage 2b longer than the lower end of the upper bear supply passage 2e and less than the lower end of the upper bear bearing portion 6b. Deformation can be suppressed.

  Here, it is desirable that the upper end of the oil supply passage 2b is disposed within the diameter of the upper bear supply passage 2e. Thereby, by blowing air from the lower end of the oil supply passage 2b or the upper bear supply passage 2e, it is possible to easily discharge cutting powder during processing of the oil supply passage 2b or foreign matters such as cleaning liquid and residue after the crankshaft 2 is cleaned. Can be done.

  Further, by providing the gas flow path 2f in the closed portion of the upper bear 6, the portion of the crankshaft 2 that forms the bearing mechanism with the upper bear bearing portion 6b can be a solid shaft. It is possible to suppress deformation. Thereby, the frictional force generated in the vertical load from the crankshaft 2 to the upper bearer bearing portion 6b can be reduced, and the efficiency of the compressor can be improved. Alternatively, the portion of the crankshaft 2 that forms the bearing mechanism with the upper bare bearing portion 6b is a solid shaft, so that the diameter of the crankshaft 2 is reduced until the amount of deformation of the crankshaft 2 is the same. can do. Thereby, the peripheral speed which determines the above-mentioned frictional force can be reduced, and the efficiency of a compressor can be improved.

  Next, the second problem, the suppression of outflow of the refrigerating machine oil 8 to the refrigeration cycle will be described. By providing the gas flow path 2 f in the closed portion of the upper bear 6 as described above, the refrigerating machine oil 8 can be circulated below the closed portion of the upper bear 6 in the sealed container 1. Thereby, the influence of the rotational motion of the said motor part can be suppressed, and the outflow to a refrigerating cycle can be suppressed. Here, it is desirable that the outlet of the gas flow path 2f provided in the closed portion of the upper bear 6 is provided with a wall surface 6d that suppresses the flow of the upper bear 6 to the upper portion of the closed portion.

  As described above, according to the present embodiment, the length of the hole serving as the oil supply passage provided in the crankshaft is set to be equal to or less than the lower end of the bearing portion of the closing member, and the gas passage is connected to the upper closing member with the diameter of the crankshaft. By arranging in the direction, the bearing portion of the crankshaft can be a solid shaft, and the efficiency of the compressor can be improved due to the effect of reducing deformation of the crankshaft.

  In addition, by using a solid shaft as the bearing portion of the crankshaft, the shaft diameter of the crankshaft can be reduced until the amount of deformation of the crankshaft becomes equivalent to the conventional one, and the peripheral speed at the bearing portion is reduced. Due to the effect, the efficiency of the compressor can be improved. In addition, the gas flow path provided in the crankshaft is disposed in the upper closing member in the radial direction of the crankshaft so that the refrigeration oil stored in the lower part of the hermetic container of the compressor is circulated below the upper closing member. It is possible to prevent a decrease in efficiency due to the outflow to the refrigeration cycle.

  That is, the efficiency can be improved by suppressing a decrease in strength due to a hole serving as an oil supply path provided in the crankshaft and a hole serving as a flow path for the refrigerant gas foamed in the oil supply path.

DESCRIPTION OF SYMBOLS 1 Airtight container 2 Crankshaft 2a Eccentric part 2b of crankshaft Oil supply path 2c Lower bear supply path 2d Eccentric part supply path 2e Upper bear supply path 2f Gas flow path 3 Cylinder 3a Cylinder inner wall surface 4 Roller 4a Roller outer wall surface 6 Upper bear 6a Upper bearer inner wall surface 6b Upper bearer bearing portion 6c Upper bearer groove 6d Gas flow path outlet upper wall surface 6e Upper bearer flat surface portion 7 Lower bearer 7a Lower bearer inner wall surface 7b Lower bearer bearing portion 7c Lower bearer groove 8 Refrigerating machine oil 9 Suction port 10 Compression Chamber 12 Supply channel outlet side space

Claims (6)

A motor part is housed in a sealed container, a crankshaft having an eccentric part that transmits the rotation of the motor part and a compression mechanism part that performs compression work by being driven by the crankshaft are provided. A cylinder, a roller disposed in the cylinder and driven to rotate by an eccentric part of a crankshaft, a vane extending to the outer periphery of the roller and entering and exiting a storage part provided in the cylinder according to the eccentric movement of the roller; A spring that presses the vane against the roller, and a closing member that has a bearing portion that closes both end faces of the cylinder and holds the crankshaft;
In the rotary compressor in which the refrigerating machine oil for lubrication of the compression mechanism part is stored in a lower part in a sealed container, and an oil supply passage for supplying the refrigerating machine oil to the compression mechanism part is provided in the crankshaft.
The crankshaft oil supply passage is arranged in the axial direction of the crankshaft from the lower end of the crankshaft to the lower end of the bearing portion of the upper closing member, and a gas passage that connects the oil supply passage and the sealed container is provided on the upper side. A rotary compressor characterized in that the rotary compressor is disposed on a closing member. In claim 1,
The upper end of the oil supply passage of the crankshaft is disposed within the diameter of a hole that serves as a supply passage for supplying the refrigerating machine oil to the bearing portion of the upper closing member. In claim 1,
A gas flow path communicating the oil supply passage and the sealed container is a supply passage from the oil supply passage to the outer wall surface of the eccentric portion of the crankshaft and a radial direction of the crankshaft within a flange portion thickness of the upper closing member A rotary compressor characterized in that it is composed of holes drilled in. In claim 3,
The rotary compressor characterized by having a wall surface that suppresses the upward flow in the hermetic container at the outlet of a hole formed in the radial direction of the crankshaft within the flange portion thickness of the upper closing member. Take the support of the crankshaft with the upper bearer having the upper bearer plane part for fixing in the sealed container,
Compressing the refrigerant by changing the volume of the compression chamber disposed in the cylinder by the rotation of the crankshaft,
In the rotary compressor that sucks up the oil in the hermetic container by the oil supply passage disposed in the crankshaft and supplies the oil to the compression chamber and its surroundings,
The crankshaft is an oil supply passage through which oil passes, and is disposed up to the position of the crankshaft that penetrates the thickness of the cylinder and corresponds to the upper bearer plane part, and is connected to the upper bearer bearing part. An oil supply passage that does not reach the position of the corresponding crankshaft and keeps the corresponding crankshaft solid;
In the upper bare plane portion, a gas flow path for discharging a refrigerant from the compression chamber to the sealed container is disposed.
A rotary compressor characterized by that. In claim 5,
The rotary compressor is characterized in that the oil supply passage communicates with a lower bear supply passage, an eccentric portion supply passage, and an upper bear supply passage in order to supply oil around the compression chamber.

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