JP3754256B2 - Refrigerant compressor - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a refrigerant compressor having a reciprocating compression mechanism used for a relatively small refrigeration apparatus such as a refrigerator or a showcase.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, a refrigerant compressor having a reciprocating compression mechanism used for a relatively small refrigeration apparatus uses a single-phase power source or an inverter power source in a hermetic container 5 as shown in the cross-sectional view of FIG. It has been known that the electric motor 7 is disposed on the lower side and the compression mechanism unit 4 disposed on the upper side via the crankshaft 15 is driven.
[0003]
These refrigerant compressors generally have a constant rotational direction, and a cantilever bearing 8 and a journal portion 9 of a crankshaft 15 supported by the bearing constitute a bearing portion 10. Further, the lubricating oil 6 is stored at the bottom of the sealed container 5, and the lubricating oil 6 sucked up by the centrifugal force from the lower end portion 16 of the crankshaft 15 passes through the inner diameter portion 11 of the crankshaft 15 and passes through the journal portion 9. Is supplied to the lower end side of the bearing portion 10 through an oil supply hole 12 penetrating from the inner diameter portion 11 provided on the lower end side to the outer diameter.
[0004]
Furthermore, the lubricating oil 6 supplied to the lower end side of the bearing portion 10 passes through a spiral first oil groove 17 having a function as a viscous pump provided on the outer peripheral surface of the journal portion 9 and is provided on the upper end side. Further, oil is supplied to the compression mechanism portion 4 through the outer diameter of the journal portion 9 and the oil supply hole 18 penetrating in the inner diameter direction leading to the eccentric portion 13. In addition, a small-diameter portion 19 serving as a non-sliding surface having a function of storing oil is also provided near the center of the outer peripheral surface of the journal portion 9.
[0005]
The position of the first oil groove 17 provided on the outer peripheral surface of the journal portion 9 is such that the pressure of the compressed gas applied to the piston 14 during the period from the start of compression to the end of compression of the compression mechanism portion 4 is as shown in FIG. Due to the load generated by acting on the eccentric part 13 of the crankshaft 15 to be driven, a load position applied to the bearing part 10 constituted by the bearing 8 and the journal part 9 supporting the crankshaft 15 is avoided.
[0006]
This load position is shown in FIG. 6 showing the cross section of the main part of the bearing part and the development of the journal part (the load 20 on the eccentric part 13 side and the load 21 on the lower end part 16 side of the journal part 9). The first oil groove 17 is provided at a position on the opposite side (about 180 degrees in the rotation direction of the shaft).
[0007]
Here, a part of the lubricating oil 6 supplied from the oil supply hole 12 to the spiral first oil groove 17 circulates through the small diameter portion 19 and enters the oil groove 17, and then flows into the oil supply hole 18. In the process, lubrication is performed in the gap of the bearing portion 10.
[0008]
By the way, in conventional refrigeration equipment, CFC (chlorofluorocarbon) or HCFC (hydrochlorofluorocarbon) refrigerants have been used as working refrigerants. However, these refrigerants are completely abolished as ozone depleting substances. Instead, it has shifted to HFC (hydrofluorocarbon) -based alternative refrigerants with zero ozone depletion potential.
[0009]
Here, with the chlorine contained in the conventional refrigerant, a chloride film was formed on the sliding surface of the compression mechanism portion of the refrigerant compressor used in the refrigeration system to improve the lubricity, but the alternative refrigerant is Such an effect cannot be expected because it does not contain chlorine. Furthermore, since the pressure of the alternative refrigerant is higher than that of the conventional refrigerant, the load on the compression mechanism increases, so the journal part of the crankshaft and the bearing that constitute the compression mechanism are more resistant to conventional ones. Abrasion is required.
[0010]
[Problems to be solved by the invention]
As described above, in a relatively small refrigeration apparatus using an HFC-based alternative refrigerant, a crankshaft supported by a cantilever bearing in a refrigerant compressor having a reciprocating compression mechanism used for the refrigeration apparatus. However, there is a problem that the oil film formation for obtaining the wear resistance is insufficient when the oil is supplied from the conventional spiral oil groove.
[0011]
The present invention provides a refrigerant compressor with improved oil film formation in the bearing portion.
[0012]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, the invention according to claim 1 includes a reciprocating compression mechanism having a cantilever bearing in an airtight container and an electric motor, and the lubricating oil sucked up by centrifugal force is journaled to the crankshaft. In a reciprocating refrigerant compressor having a spiral first oil groove on the outer peripheral surface of a journal portion supported by a bearing and supported by a bearing, the reciprocating refrigerant compressor communicates with the first oil groove in a counter-rotating direction. By providing the second oil groove having the end, oil film formation of the bearing portion is promoted.
[0013]
Further, the second oil groove communicates with the end of the first oil groove on the side of the eccentric portion and is provided in the circumferential direction of the crankshaft, thereby facilitating the formation of an oil film on the bearing portion. It is.
[0014]
According to a second aspect of the present invention , the end of the second oil groove is provided within a range of 60 degrees to 120 degrees in the counter-rotating direction from the eccentric direction of the crankshaft on the outer peripheral surface of the journal portion. This promotes the formation of an oil film at a position where the maximum load is applied at the portion.
[0015]
The invention according to claim 3 is provided with a reciprocating compression mechanism having a cantilever bearing in an airtight container and an electric motor, and lubricating oil sucked up by centrifugal force is supplied to a journal portion of a crankshaft. In the reciprocating refrigerant compressor in which a spiral first oil groove is provided on the outer peripheral surface of the supported journal portion and a small-diameter portion having a function of storing oil is provided near the center of the outer peripheral surface. By facilitating the formation of an oil film in the bearing portion by providing a second oil groove having a terminal end substantially parallel to the first oil groove from the diameter portion toward the journal end portion on the eccentric portion side. It is.
[0016]
According to a fourth aspect of the present invention , the end of the second oil groove is provided within a range of 60 degrees to 120 degrees in the counter-rotating direction from the eccentric direction of the crankshaft on the outer peripheral surface of the journal portion. This promotes the formation of an oil film at a position where the maximum load is applied at the portion.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described with reference to the drawings. In addition, the same code | symbol is used regarding the same structure as the past.
[0018]
FIG. 1 is a view showing a cross-section of the main part of the bearing part of the present invention and the development of the journal part. In the figure, reference numeral 17 denotes a first oil groove having a spiral shape similar to the conventional one. By providing second oil grooves 27 and 28 having terminal ends 25 and 26 in the counter-rotating direction in communication with the groove, oil supply holes are provided. A part of the lubricating oil supplied from 12 to the oil groove 17 is supplied to the oil groove 28, and a part of the lubricating oil circulates through the narrow diameter portion 19 and enters the oil groove 17, and then flows into the oil supply hole 18. And a part is supplied to the oil groove 27.
[0019]
In these supply processes, the lubricating oil enters the gap between the bearing portion 10 formed by the outer peripheral surface of the journal portion 9 and the bearing 8 and performs lubrication. However, in the present invention, the lubricating oil is placed at a position where the load on the bearing portion 10 increases. By supplying oil through the oil grooves 27 and 28 close to each other, the formation of an oil film at the sliding portion is promoted, and a refrigerant compressor having high wear resistance can be supplied even if an HFC-based refrigerant is used.
[0020]
FIG. 2 is a diagram showing the development of the journal portion according to the second embodiment of the present invention. In the refrigerant compressor according to the present invention, the crankshaft is supported by a cantilever bearing, and the pressure of the compressed gas acting on the piston of the compression mechanism acts on the eccentric part of the crankshaft to be generated. Of the crankshaft is large on the eccentric part side of the crankshaft (corresponding to the bearing load 20 shown in the figure) and small on the lower end side of 1/2 or less (corresponding to the bearing load 21 in the figure).
[0021]
Furthermore, since the load of the bearing portion is maximized at both ends, the bearing portion communicates with the end portion on the eccentric portion side of the spiral first oil groove 17 provided on the outer peripheral surface of the journal portion 9, and is a circle in the counter-rotating direction. By providing the second oil groove 27 having the terminal end 25 in the circumferential direction on the eccentric part side of the crankshaft of the bearing part, it becomes possible to supply oil to the vicinity of the maximum load position of the bearing part, and the formation of an oil film at the maximum load position is promoted. Thus, a refrigerant compressor having high wear resistance can be supplied even if an HFC-based refrigerant is used.
[0022]
FIG. 3 is a diagram showing the development of the journal portion according to the third embodiment of the present invention. In the present invention, the second oil groove 27 having a terminal end 25 substantially parallel to the first oil groove 17 that communicates the oil supply near the maximum load position on the eccentric portion side of the journal portion 9 to the small diameter portion 19. By providing, it is possible to reduce the strength reduction of the maximum load position on the eccentric part side of the journal part 9, and it is possible to promote the formation of an oil film at the maximum load position.
[0023]
The position of the maximum load in the circumferential direction of the journal portion (corresponding to the bearing load 20 shown in the figure) is approximately 120 to 180 degrees in the counter-rotating direction from the eccentric direction of the crankshaft. Similarly, the position of 25 is preferably 60 to 120 degrees in the counter-rotating direction from the eccentric direction, so that it is possible to ensure the formation of an oil film on the bearing portion that receives the maximum load, and to prevent wear and reduce sliding resistance. As a result, the efficiency of the refrigerant compressor can be improved.
[0024]
【The invention's effect】
As described above, according to the first aspect of the present invention, the reciprocating compression mechanism having a cantilevered bearing and the electric motor are provided in the sealed container, and the lubricating oil sucked up by the centrifugal force is collected in the journal portion of the crankshaft. In the reciprocating refrigerant compressor having a spiral first oil groove on the outer peripheral surface of the journal portion supported by the bearing, the reciprocating refrigerant compressor communicates with the first oil groove and terminates in the counter-rotating direction. By providing the second oil groove, the formation of an oil film in the bearing portion is promoted, and it becomes possible to supply a refrigerant compressor having high wear resistance even when an HFC-based refrigerant is used.
[0025]
Further, the second oil groove communicates with the end portion on the eccentric portion side of the first oil groove and is provided in the circumferential direction of the crankshaft, thereby facilitating the formation of an oil film on the bearing portion on the maximum load side. In addition, even when an HFC-based refrigerant is used, it is possible to supply a refrigerant compressor having high wear resistance.
[0026]
According to the invention of claim 2, the end of the second oil groove is provided in the range of 60 degrees to 120 degrees in the counter-rotating direction from the eccentric direction of the crankshaft on the outer peripheral surface of the journal portion. Formation of an oil film at the bearing maximum load portion is promoted, and wear prevention and sliding resistance can be reduced.
[0027]
According to the invention of claim 3, a reciprocating compression mechanism having a cantilevered bearing in an airtight container and an electric motor are provided, and lubricating oil sucked up by centrifugal force is supplied to a journal part of a crankshaft, The outer circumferential surface of the journal part supported by the first spiral oil groove and the end substantially parallel to the first oil groove from the narrow diameter part toward the eccentric end side journal. By providing the second oil groove, it is possible to reduce the strength reduction of the maximum load position on the eccentric part side of the journal part, and further, the formation of the oil film on the bearing part on the maximum load side is promoted. Even if a refrigerant is used, it is possible to supply a refrigerant compressor having high wear resistance.
[0028]
According to the invention of claim 4, the end of the second oil groove is provided within a range of 60 degrees to 120 degrees in the counter-rotating direction from the eccentric direction of the crankshaft on the outer peripheral surface of the journal portion. The formation of an oil film at the bearing maximum load part is promoted, and wear prevention and sliding resistance can be reduced.
[Brief description of the drawings]
FIG. 1 is a view showing a cross section of a main part of a bearing part and a development of a journal part according to the present invention.
FIG. 2 is a view showing development of a journal portion according to the second embodiment.
FIG. 3 is a diagram showing development of a journal portion according to the third embodiment.
FIG. 4 is a cross-sectional view of a conventional refrigerant compressor.
FIG. 5 is a view showing a cross section of the main part of the bearing part and a load applied to the bearing part.
FIG. 6 is a view showing a cross section of the main part of the bearing part and the development of the journal part.
[Explanation of symbols]
4 Compression elements 12 and 18 Oil supply hole 13 Eccentric part 14 Piston 15 Crankshaft 17 First oil groove 19 Narrow diameter parts 25 and 26 Terminal parts 27 and 28 Second oil groove

Claims (4)

A reciprocating compression mechanism with a cantilevered bearing in an airtight container and an electric motor. Lubricant sucked up by centrifugal force is supplied to the journal part of the crankshaft, and the outer peripheral surface of the journal part supported by the bearing. In the reciprocating refrigerant compressor having a spiral first oil groove, a second oil groove communicating with the first oil groove and having a terminal end in the counter-rotating direction is formed on the outer peripheral surface of the journal portion. In the provided refrigerant compressor,
The second oil groove communicates with an end of the first oil groove on the side of the eccentric portion, and is provided in the circumferential direction of the outer peripheral surface of the journal portion . The end of the second oil groove, according to claim 1, characterized in that provided in the range of eccentricity direction of the crank shaft at the outer circumferential surface of the journal portion of 60 to 120 degrees in a counter-rotational direction Refrigerant compressor.   A reciprocating compression mechanism with a cantilevered bearing in an airtight container and an electric motor. Lubricating oil sucked up by centrifugal force is supplied to the journal part of the crankshaft, and the outer peripheral surface of the journal part supported by the bearing. In the reciprocating refrigerant compressor provided with a spiral first oil groove and a small diameter portion having a function of storing oil near the center of the outer peripheral surface, the eccentric portion side of the small diameter portion is provided. A refrigerant compressor characterized in that a second oil groove having a terminal end substantially parallel to the first oil groove is provided toward the end of the journal. The end of the second oil groove, according to claim 3, characterized in that provided in the range of eccentricity direction of the crank shaft at the outer circumferential surface of the journal portion of 60 to 120 degrees in a counter-rotational direction Refrigerant compressor.

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