JP5680500B2 - Hermetic compressor and refrigerator using the same - Google Patents

Description

  The present invention relates to a hermetic compressor and a refrigerator using the same, and is particularly suitable for a hermetic compressor having a reciprocating piston.

  Recently, demands for energy saving of home refrigerators are increasing, and in low-capacity hermetic compressors used in refrigerators, low-speed operation of compressors by inverter control has been attempted. For this reason, there is a demand for further improvement in efficiency and improved reliability of the bearing sliding portion during low-speed operation of the hermetic compressor.

  In order to improve the efficiency of the hermetic compressor, it is an important issue to reduce the mechanical friction loss. For this reason, for example, Patent Document 1 describes a hermetic compressor in which mechanical friction loss of a thrust sliding surface supporting a thrust load acting on a crankshaft is reduced and reliability can be improved. Has been.

JP 2010-138777 A

“Matsushita Technical Journal” Vol. 51, No. 1, February 2005, pp. 70-74, “Technology for improving the performance of fluid dynamic bearings for mobile HDD”, Takafumi Asada and 3 other authors

However, the thing of the said patent document 1 has the following subjects.
In Patent Document 1, a support member having a centering function is arranged on the upper surface of a cylinder block against the inclination of a shaft (crankshaft) caused by a compression load or the like, and the shaft rotates on the thrust surface of the support member. Thus, a thrust bearing having a herringbone type dynamic pressure mechanism for generating an oil film pressure is formed. In the device described in Patent Document 1, in order for the support member to exhibit the aligning function, a necessary gap needs to exist between the support member and the upper surface of the cylinder block. Then, the lubricating oil lifted up to the upper end of the main shaft by the oil supply mechanism of the shaft leaks around the thrust surface. For this reason, the eccentric shaft located above the thrust surface, the sliding part between the piston pin and the connecting means, and the reciprocating sliding part between the piston and the cylinder are insufficiently lubricated, increasing the friction and wear of these sliding parts. There is a fear. In particular, during low-speed operation, the oil supply pump capacity of the shaft is reduced and there is no margin in the amount of oil supply, so the effect of oil leakage in the oil supply path can cause serious problems. In addition, since the support member having the aligning function is a thin plate shape, it is difficult to ensure the flatness of the thrust surface, and the load capacity of the dynamic pressure mechanism is reduced, and the structure of the support member is complicated. There is also a problem that costs are likely to increase.

  Furthermore, the herringbone type dynamic pressure mechanism disclosed in the above-mentioned Patent Document 1 simply seals a hydrodynamic fluid bearing (for example, see Non-Patent Document 1) generally used in the rotation main shaft portion of OA and AV equipment. It is used for the thrust surface of a compact compressor. However, usage conditions (rotational speed, load load, etc.) differ greatly between a hermetic compressor and a device using a hydrodynamic bearing as described in Non-Patent Document 1, and a thrust bearing sliding portion. No particular consideration has been given to the problems inherent to the hermetic compressor in which foreign matter may be mixed into the lubricating oil due to overheating problems, spatter generation during chamber welding, and the like. That is, the reduction of the mechanical friction loss on the thrust sliding surface of the hermetic compressor and consideration for its reliability have not been sufficient.

  An object of the present invention is to provide a hermetic compressor capable of improving efficiency by reducing mechanical friction loss of a thrust sliding surface supporting a thrust load acting on a crankshaft and improving reliability, and a refrigerator using the same. There is to get.

In order to achieve the above object, the present invention includes a sealed container, a compression element and an electric element housed in the closed container, and the compression element is driven by the electric element via a crankshaft, and the crank The lower end of the shaft is immersed in the lubricating oil stored in the sealed container, and the lubricating oil is supplied to the sliding portion of the crankshaft and the compression element by an oil pump provided at the lower end of the crankshaft. Further, in the hermetic compressor including a bearing portion that supports a thrust load acting on the crankshaft, the bearing portion has a bearing thrust surface for supporting the thrust load acting on the crankshaft. The bearing thrust surface is provided with a dynamic pressure groove for generating an oil film pressure in the lubricating oil flowing through the gap of the thrust sliding surface by the rotation of the crankshaft. From the inside of the bearing thrust surface extends through outwardly, the dynamic pressure grooves is constituted by a herringbone oil groove, the herringbone oil groove, the flow of lubricating oil from the inside of the bearing thrust face outwardly In addition to the herringbone oil groove, an oil supply passage penetrating from the inner side to the outer side of the bearing thrust surface is provided on the bearing thrust surface. The lubricating oil is supplied to the bearing thrust surface, and the supplied lubricating oil promotes the cooling effect of the bearing thrust surface, and can discharge foreign matters mixed in the lubricating oil. Features.

  According to the present invention, a hermetic compressor capable of reducing the mechanical friction loss of the thrust sliding surface that supports the thrust load acting on the crankshaft and improving efficiency and also improving reliability can be used. There is an effect that can be obtained refrigerator.

It is a longitudinal cross-sectional view which shows Example 1 of the hermetic compressor of this invention. It is a principal part expanded sectional view of the cylinder block vicinity shown in FIG. It is a top view of the cylinder block shown in FIG. FIG. 4 is an enlarged plan view of a bearing thrust surface shown in FIG. 3. FIG. 5 is a cross-sectional view taken along line AA in FIG. 4. It is a principal part expanded sectional view of the cylinder block vicinity in Example 2 of the hermetic compressor of this invention. It is a top view of the cylinder block shown in FIG. FIG. 8 is an enlarged plan view near the bearing thrust surface shown in FIG. 7. It is a top view of the cylinder block in Example 3 of the hermetic compressor of the present invention, and is a figure equivalent to FIG. FIG. 10 is an enlarged plan view near the bearing thrust surface shown in FIG. 9. It is sectional drawing which shows the Example of the refrigerator in which the hermetic compressor of this invention was mounted.

  Hereinafter, specific embodiments of the present invention will be described in detail with reference to the drawings. Note that, in each drawing, the portions denoted by the same reference numerals indicate the same or corresponding portions.

A first embodiment of the hermetic compressor of the present invention will be described with reference to FIGS.
First, the overall configuration of the present embodiment will be described with reference to FIGS. FIG. 1 is a longitudinal sectional view of a hermetic compressor according to the present embodiment, FIG. 2 is an enlarged sectional view of a main part near the cylinder block shown in FIG. 1, and FIG. 3 is a plan view of the cylinder block shown in FIG.

  As shown in FIG. 1, a hermetic compressor 50 according to this embodiment stores an electric element 2 including a stator 2 a and a rotor 2 b and a compression element 3 in a hermetic container 1. The compression element 3 includes a cylinder block 5 in which a bearing portion 5c and a frame portion 5b are integrally formed. A cylinder 5a is formed in the cylinder block 5, and a piston 7 reciprocates in the cylinder 5a. It is configured in a so-called reciprocating type. The piston 7 is connected to an eccentric shaft 8 b of the crankshaft 8 through a connecting rod 6.

  The crankshaft 8 includes a main shaft 8a, an eccentric shaft 8b, and a flange portion 8c that integrally connects the main shaft 8a and the eccentric shaft 8b. The lower end surface of the flange portion 8c is as shown in FIG. It is an axial thrust surface 8ca. The cylinder block 5 is provided with a bearing portion 5c, and the crankshaft 8 is rotatably supported by the bearing portion 5c. An electric motor is provided below the main shaft 8a of the crankshaft 8 as shown in FIG. The rotor 2b of the element 2 is fixed. The stator 2a of the electric element 2 is fixed to the lower part of the frame portion 5b. The compression element 3 is elastically supported on the bottom of the hermetic container 1 by a coil spring via the stator 2a fixed to the lower part of the frame part 5b.

  As shown in FIG. 2, the upper end surface of the bearing portion 5c of the cylinder block 5 is a bearing thrust surface 5ca so as to support the shaft thrust surface 8ca of the crankshaft 8, and the outer periphery of the bearing thrust surface 5ca. A concave annular groove 13 is formed in the part so as to dig out the upper surface of the frame part 5b.

  As the rotor 2b of the electric element 2 rotates, the crankshaft 8 rotates, and the eccentric shaft 8b also rotates eccentrically, and the piston 7 is connected to the bore of the cylinder 5a via the connecting rod 6 connected to the eccentric shaft 8b. It is designed to reciprocate inside. The top of the cylinder 5 a is closed by a cylinder head 10 in which a suction valve and a discharge valve (not shown) are incorporated, and a compression chamber 12 is formed between the cylinder 5 a and the piston 7. In the compression chamber 12, the refrigerant is sucked and compressed by the reciprocating motion of the piston 7 and is discharged from the discharge valve.

Further, the lubricating oil 4 is stored at the bottom of the sealed container 1, and the stored lubricating oil 4 is attached to the center hole 8 d at the bottom of the crankshaft 8 by the rotation of the crankshaft 8. The oil pump 18 is sucked by the centrifugal pump action, guided upward through the spiral groove 8f formed on the outer periphery of the main shaft 8a from the lower communication hole 8e, and supplied to the sliding portion of the main shaft 8a and the shaft thrust surface 8ca. Further, it is conveyed through the upper communication hole 8g to the center hole 8h of the eccentric shaft 8b. From here, the lubricating oil 4 lubricates the large-end bearing portion of the connecting rod 6 rotatably connected to the eccentric shaft 8b through the eccentric shaft lateral hole 8i and the ball joint portion connected to the piston 7. It is injected from the lubricating oil radiation hole 8j provided so as to partially penetrate the balance weight 9 attached to the upper end of the shaft 8b, and finally injected from the upper end portion of the eccentric shaft 8b to the periphery. Lubrication and sealing between the piston 7 and the cylinder 5a are mainly performed by the injected lubricating oil 4.
The lubricating oil 4 scattered and accumulated on the upper surface of the cylinder block 5 falls downward through the oil return hole 5ba shown in FIG. 3, and is collected and stored at the bottom in the sealed container 1.

  Next, the flow of the refrigerant will be described. The refrigerant that has flowed through the suction pipe (not shown) connected in the sealed container 1 is sucked into the compression chamber 12 of the cylinder 5a through the plastic suction silencer (not shown) and compressed. The compressed refrigerant enters the discharge chamber in the head cover 11 from the cylinder head 10, passes through a discharge silencer (not shown) formed integrally with the cylinder block 5 from here, passes through the discharge pipe 19, and is discharged into the discharge pipe. It is comprised so that it may flow out from 20 to an external refrigeration cycle.

  A thrust load is applied to the crankshaft 8 by the weight of the crankshaft 8, the balance weight 9 and the rotor 2b, and the magnetic thrust of the rotor 2b resulting from the deviation of the magnet center between the stator 2a and the rotor 2b. This thrust load is supported by the bearing thrust surface 5 ca at the upper end of the bearing portion 5 c of the cylinder block 5 via the shaft thrust surface 8 ca of the crankshaft 8. In a normal operation state of the hermetic compressor 50, a compression load acts on the piston 7, so that the crankshaft 8 is slightly inclined within the bearing clearance range of the bearing portion 5c. For this reason, the thrust load supported by the bearing thrust surface 5ca is also likely to be an uneven load. However, in this embodiment, since the concave annular groove 13 is formed on the upper surface of the frame portion 5b of the cylinder block 5 at the outer peripheral portion of the bearing thrust surface 5ca, the rigidity of the bearing portion 5c including the bearing thrust surface 5ca is increased. In a state where is sufficiently secured, the entire bearing portion has a flexible structure with respect to the shaft inclination. Thereby, even if the crankshaft 8 is inclined by the compression load, it is possible to prevent the local thrusting of the bearing portion 5c that receives the bearing thrust surface 5ca and the main shaft 8a.

In general, as a means for increasing the load capacity of a thrust bearing, it is well known to use a hydrodynamic fluid bearing structure provided with dynamic pressure grooves. This is to generate an oil film pressure by generating a dynamic pressure by the dynamic pressure groove in the oil flowing through the bearing gap by the rotation of the shaft. However, there is no example in which the effect of the hydrodynamic bearing structure is verified within the dimensional specification of a thrust bearing in a hermetic compressor and the restrictions on the operating environment. Therefore, the mechanical friction torque in various thrust bearing specifications was measured using actual compression elements, and the thrust loss (the mechanical friction loss on the thrust surface) was evaluated. An example of the evaluation results (operating conditions: rotational speed 1500 min ⁻¹ , oil temperature 50 ° C.) is shown in Table 1.

  This table 1 shows that the thrust loss ratio of a parallel plate bearing that has been generally adopted as a thrust bearing of a hermetic compressor is 1.0, and various dynamic pressure bearings (dynamic pressure fluids having dynamic pressure grooves) corresponding thereto. This is a comparison of the thrust loss ratio of the bearing. As shown in Table 1, it became clear that the thrust loss can be reduced by adopting the hydrodynamic bearing as compared with the conventional one. It was also found that the thrust loss can be greatly reduced by adopting the hydrodynamic bearing structure of tapered land and herringbone among the hydrodynamic bearings. The results in Table 1 confirmed that the same effect can be obtained in the performance test of the actual compressor of the hermetic compressor.

  Next, the structure of the bearing thrust surface 5ca in the first embodiment will be described with reference to FIGS. 4 is an enlarged view of the bearing thrust surface of FIG. 3, and FIG. 5 is a cross-sectional view taken along line AA in FIG. In this embodiment, a dynamic pressure groove having the structure shown in FIGS. 4 and 5 is employed in the bearing thrust surface 5ca. That is, substantially V-shaped herringbone oil grooves (dynamic pressure grooves) 14 are formed on the bearing thrust surface 5ca of the cylinder block 5 at an equal pitch all around the thrust surface. In FIG. 4, a thick arrow indicates the rotation direction of the crankshaft.

  The herringbone oil groove shown in FIG. 4 has a bearing thrust surface from the inner side to the outer side of the bearing thrust surface 5ca in order to prevent overheating of the bearing in the hermetic compressor and facilitate the discharge of foreign matter from the thrust sliding surface. The radius R0 of the part where the inner and outer oil grooves of the herringbone oil groove 14 are connected to each other is made into a shape represented by the formula 1 so that there is an oil flow passing through 5ca.

  Here, R1 is an inner radius of the bearing thrust surface 5ca, and R2 is an outer radius of the bearing thrust surface 5ca. As a result, the outward pumping action by the herringbone oil groove 14 can be increased more than the inward pumping action, so that an outward oil flow can be generated.

  In this embodiment, the groove width of the herringbone oil groove 14 is made constant. However, this is to facilitate machining by a micro-diameter end mill, and the groove width dimension is not constant. In particular, when a processing method other than the above-described machining is employed, the groove width dimension may not be constant.

The groove depth dimension h of the herringbone oil groove 14 shown in FIG. 5 is preferably about 20 to 50 μm in consideration of load capacity characteristics and machinability of the herringbone oil groove 14. By doing so, mass production processing of the hermetic compressor including the bearing thrust surface can be easily performed. Further, only the portion of the bearing thrust surface 5ca (thrust bearing portion) is a ring-shaped separate part to form a thrust bearing, and a dynamic pressure groove is formed on the thrust bearing by sizing processing, coining processing or the like, and this is formed in the bearing portion 5c. If it is installed on the upper surface and fixed, mass productivity can be further improved.
Note that the hermetic compressor of the present embodiment is particularly suitable for an inverter-driven one that can be controlled at a plurality of operating frequencies including at least an operating frequency equal to or lower than the commercial power supply frequency, and is a low speed that is frequently used. Compressor efficiency during operation can be improved.

  According to the hermetic compressor of the present embodiment described above, the bearing thrust surface 5ca of the cylinder block 5 with which the shaft thrust surface 8ca of the crankshaft 8 abuts penetrates from the inside to the outside of the bearing thrust surface 5ca. Since the dynamic pressure groove (herringbone oil groove 14) is formed and the dynamic pressure groove is configured to generate a flow of lubricating oil from the inside to the outside, the following effects can be obtained. That is, since the oil film can be held on the bearing thrust surface 5ca with a simple structure, the mechanical friction loss of the thrust sliding surface (the sliding surface between the shaft thrust surface 8ca and the bearing thrust surface 5ca) can be reduced. . Further, the bearing 5c including the bearing thrust surface 5ca can be cooled (prevention of overheating), and foreign matter can be easily discharged from the thrust sliding surface.

  Furthermore, in this embodiment, since the concave annular groove 13 is provided on the outer periphery of the bearing thrust surface 5ca, it is possible to prevent local contact of the bearing portion 5c including the bearing thrust surface 5ca. The mechanical friction loss of the bearing portion 5c including the bearing thrust surface 5ca can be reduced, and the reliability of the hermetic compressor can be improved.

  In particular, by adopting this embodiment as a hermetic compressor used in a refrigerator or the like that is frequently used in low-speed operation of the compressor, it is possible to improve the compressor efficiency and improve the reliability of the compressor. It is done.

  Next, a second embodiment of the hermetic compressor according to the present invention will be described with reference to FIGS. FIG. 6 is an enlarged cross-sectional view of the main part in the vicinity of the cylinder block in the hermetic compressor 51 of the present embodiment (corresponding to FIG. 2), and FIG. 7 is a plan view of the cylinder block shown in FIG. 8 is an enlarged plan view of the vicinity of the bearing thrust surface shown in FIG.

  In the second embodiment, as shown in FIGS. 6 to 8, the oil supply passage 15 for supplying lubricating oil to the bearing thrust surface 5 ca is changed from the inner side (inner peripheral side) to the outer side (outer peripheral side) of the bearing thrust surface 5 ca. It is provided so as to penetrate through, and the lubricating oil supplied to the oil supply passage 15 promotes the cooling effect of the thrust surface, and can easily discharge foreign matters mixed in the lubricating oil. is there.

  More specifically, an oil supply passage 15 is provided on the bearing thrust surface 5ca of the cylinder block 5 of the hermetic compressor 51 at a portion on the compression chamber 12 side. Further, substantially V-shaped herringbone oil grooves 14 are formed at an equal pitch on the bearing thrust surface 5ca excluding the portion where the oil supply passage 15 is formed. The flow passage cross-sectional area of the oil supply passage 15 is sized so as not to obstruct lubrication of the sliding portion of the compression element 3 located above the bearing thrust surface 5ca.

Other configurations are the same as those of the first embodiment.
According to this embodiment, in addition to the same effects as those of the first embodiment, the bearing thrust surface 5ca can be more effectively cooled by the lubricating oil supplied to the oil supply passage 15. . In addition, it becomes easier to discharge foreign matters mixed in the lubricating oil, and the reliability of the hermetic compressor can be further improved.

  Next, Embodiment 3 of the hermetic compressor of the present invention will be described with reference to FIGS. 9 and 10. 9 is a plan view of a cylinder block in the hermetic compressor 52 of the present embodiment (a view corresponding to FIG. 3), and FIG. 10 is an enlarged plan view of the vicinity of the bearing thrust surface shown in FIG.

  In the third embodiment, a spiral spiral oil groove (dynamic pressure groove) 14 ′ is formed on the bearing thrust surface 5 ca of the cylinder block 5 at an equal pitch on the entire circumference of the bearing thrust surface. In this embodiment, the spiral oil groove 14 ′ prevents overheating of the bearing portion 5 c and the bearing thrust surface 5 ca in the hermetic compressor 52, and the thrust sliding surface (the axial thrust surface 8 ca and the bearing thrust surface 5 ca It is configured to facilitate the discharge of foreign matter from the sliding surface. That is, the spiral oil groove 14 'is configured to have a pumping action outward so that oil flows through the bearing thrust surface from the inside to the outside of the bearing thrust surface 5ca. Yes.

  In the present embodiment, the groove width of the spiral oil groove 14 'is formed to be constant. This is because the machining is easy as in the case of the herringbone oil groove 14 described above. The shape such as the groove width dimension can be arbitrarily selected as in the above-described embodiment.

The groove depth dimension of the spiral oil groove 14 ′ is determined by the amount of oil supplied to the bearing thrust surface 5 ca related to the number of spiral oil grooves in addition to the load capacity characteristics and the machinability of the spiral oil groove 14 ′. The size of the compression element 3 (see FIG. 1) located above the thrust surface 5ca is defined within a range that does not impede lubrication of the sliding portion.
Other configurations are the same as those of the first embodiment. Also in this embodiment, the same operations and effects as those of the first and second embodiments can be obtained.

Next, an embodiment of a refrigerator equipped with the above-described hermetic compressor of the present invention will be described with reference to FIG.
FIG. 11 is a cross-sectional view of a refrigerator equipped with the hermetic compressor of the present invention. The refrigerator 60 shown in this figure employs a refrigeration cycle using R600a (isobutane) as a refrigerant gas. As the hermetic compressor, the hermetic compressor according to any of the embodiments of the present invention described above is mounted.

  As shown in FIG. 11, the refrigerator 60 has a refrigerator main body (housing) 61 in which a refrigerator compartment 62, an upper freezer compartment 63, a lower freezer compartment 64, a vegetable compartment 65, and a cooler 66 are housed. In addition, a hermetic compressor is installed in the lower part on the back side in the refrigerator main body 61. In this embodiment, the hermetic compressor 50 according to the first embodiment is mounted as the hermetic compressor.

  When the hermetic compressor 50 is driven, the refrigeration cycle using the refrigerant gas R600a operates to cool the inside of the refrigerator 60.

  In the refrigerator 60 shown in FIG. 11, as described above, the hermetic compressor 50 according to the first embodiment is used as the hermetic compressor, but the hermetic compressor mounted on the refrigerator 60 is an example. 1 is not limited to the hermetic compressor 50 according to the first embodiment, and the hermetic compressor 51 or 52 described in the second and third embodiments may be used. It goes without saying that a hermetic compressor can be used.

  The hermetic compressor of the present invention is not limited to a refrigerator, and can be similarly applied to a refrigerating and air conditioning system such as a room air conditioner or a refrigerator. The hermetic compressor of the present invention is adopted. By doing so, the efficiency of the refrigerating and air-conditioning system can be greatly improved and its reliability can be improved. The refrigerant used in the refrigeration cycle is not limited to R600a, and an optimum refrigerant can be used according to the refrigeration air conditioning system.

  As described above, according to this embodiment, the oil film pressure is applied to the lubricating oil that flows through the gap of the thrust sliding surface by the rotation of the crankshaft on the bearing thrust surface of the bearing portion that supports the thrust load acting on the crankshaft. Since the dynamic pressure grooves that generate the pressure are formed, the mechanical friction loss on the thrust sliding surface can be greatly reduced. Especially in the hermetic compressor that can control the rotation speed, during frequent low-speed operation The compressor efficiency can be improved. Therefore, the efficiency of a refrigerator equipped with the hermetic compressor of the present embodiment can be improved. Further, since the dynamic pressure groove is composed of a dynamic pressure groove such as a herringbone oil groove or a spiral oil groove that penetrates from the inner side to the outer side of the bearing thrust surface, the dynamic pressure groove extends from the inner side to the outer side. Lubricating oil can be flowed toward. Therefore, not only can the mechanical friction loss on the thrust sliding surface be significantly reduced, but also the bearing part including the bearing thrust surface can be prevented from overheating, and foreign matters mixed in the lubricating oil can be easily discharged from the thrust sliding surface. Therefore, reliability can be improved.

  Further, if the bearing thrust surface is provided with an oil supply passage penetrating from the inner side to the outer side of the bearing thrust surface, the foreign matter discharging effect and the thrust sliding surface cooling effect can be further improved.

  In addition, by providing a concave annular groove on the outer peripheral portion of the bearing thrust surface, the bearing portion including the bearing thrust surface can be made into a flexible structure, so that local contact between the bearing thrust surface and the bearing portion can be prevented. The mechanical friction loss can be reduced, and the reliability of the hermetic compressor can be further improved.

  Therefore, according to the present embodiment, a hermetic compressor capable of reducing the mechanical friction loss of the thrust sliding surface that supports the thrust load acting on the crankshaft and improving the efficiency, and improving the reliability, and A refrigerator using this can be obtained.

  In addition, this invention is not limited to the thing of the Example mentioned above, It can implement by changing suitably in the range which does not deviate from the meaning of this invention.

1 ... Sealed container,
2 ... Electric element, 2a ... Stator, 2b ... Rotor,
3 ... compression element, 4 ... lubricating oil,
5 ... Cylinder block, 5a ... Cylinder, 5b ... Frame part, 5ba ... Oil return hole,
5c ... bearing portion, 5ca ... bearing thrust surface,
6 ... connecting rod, 7 ... piston,
8 ... crankshaft, 8a ... main shaft, 8b ... eccentric shaft, 8c ... flange,
8ca: shaft thrust surface, 8d: center hole, 8e: lower communication hole, 8f: spiral groove,
8g ... Upper communication hole, 8h ... Eccentric shaft center hole, 8i ... Eccentric shaft side hole, 8j ... Lubricating oil radiation hole,
9 ... Balance weight, 10 ... Cylinder head, 11 ... Head cover,
12 ... compression chamber, 13 ... annular groove,
14 ... Herringbone oil groove (dynamic pressure groove), 14 '... Spiral oil groove (dynamic pressure groove),
15 ... refueling passage,
18 ... Oil pump,
19 ... discharge pipe, 20 ... discharge pipe,
50, 51, 52 ... hermetic compressor,
60 ... Refrigerator, 61 ... Refrigerator body, 62 ... Refrigerator room, 63 ... Upper freezer room,
64 ... Lower refrigeration room, 65 ... Vegetable room, 66 ... Cooler.

Claims (4)

A hermetic container, and a compression element and an electric element housed in the hermetic container. The compression element is driven by the electric element via a crankshaft, and a lower end portion of the crankshaft is stored in the hermetic container. The lubricating oil is immersed in the lubricating oil and is supplied to the sliding portion of the crankshaft and the compression element by an oil pump provided at the lower end of the crankshaft. In a hermetic compressor including a bearing portion that supports a thrust load that acts,
The bearing portion has a bearing thrust surface for supporting a thrust load acting on the crankshaft, and an oil film pressure is applied to the lubricating oil flowing through the gap of the thrust sliding surface by the rotation of the crankshaft. Is formed, and this dynamic pressure groove penetrates from the inside to the outside of the bearing thrust surface ,
The dynamic pressure groove is composed of a herringbone oil groove, and the herringbone oil groove is formed so that a flow of lubricating oil is generated from the inside to the outside of the bearing thrust surface,
In addition to the herringbone oil groove, an oil supply passage penetrating from the inner side to the outer side of the bearing thrust surface is provided on the bearing thrust surface, and this oil supply passage supplies lubricating oil to the bearing thrust surface. The hermetic compressor is characterized in that the supplied lubricating oil accelerates the cooling effect of the bearing thrust surface and can discharge foreign matters mixed in the lubricating oil . 2. The hermetic compressor according to claim 1 , wherein a concave annular groove is formed in an outer peripheral portion of the bearing thrust surface.   2. The hermetic compressor according to claim 1, wherein the rotational speed is controlled at a plurality of operating frequencies including at least an operating frequency equal to or lower than a commercial power source frequency.   A refrigerator comprising the refrigeration cycle using R600a as a refrigerant, and the hermetic compressor according to claim 1 used as the hermetic compressor used in the refrigeration cycle.

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