JP2013100798A - Hermetic compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a highly-efficient hermetic compressor which improves slide performance and durability in a flange of a rotary shaft and a thrust surface.SOLUTION: A thrust washer 122 is provided between the flange 112 and the thrust surface 121. The thrust washer 122 is disposed to contact with the flange 112. The thrust washer 122 has elasticity in a gravity direction around the entire opposite side 116a of a compressor chamber, is also disposed to contact with the thrust surface 121, and has a rotation regulation means 123 for regulating rotation together with the thrust surface 121. The highly-efficient hermetic compressor can be provided to have favorable slide performance on a contact surface between the flange 112 and the thrust washer 122 for smooth rotation, and to further have durability.

Description

  The present invention relates to a hermetic compressor used in a refrigeration cycle such as a refrigerator-freezer.

  A hermetic compressor in which a compression element is housed in an upper part of a block, which is a support frame of a hermetic container, and an electric element is housed in a lower part of the block, is generally used in a refrigeration apparatus or an air conditioner. In such a hermetic compressor, the driving force of the electric element is transmitted to the compression element by a shaft that is rotatably supported by a bearing portion provided substantially at the center (see, for example, Patent Document 1). .

  The prior art hermetic compressor will be described below with reference to the drawings.

  FIG. 8 is a longitudinal sectional view of a conventional hermetic compressor. In FIG. 8, the electric element 4 having the stator 18 and the rotor 8 and the compression element 2 are arranged in the upper part of the hermetic container 1. A shaft 7 is inserted into the bearing portion 6 of the cylinder block 3 constituting the compression element 2, and a rotor 8 is fixed to the outer peripheral portion of the shaft 7, and a slider 11 of the piston 10 via an eccentric shaft portion 9. Is engaged. Inside the shaft 7, a centrifugal pump 12 opened at the lower end to the lubricating oil 17 is formed. Further, a thrust surface (not shown) for receiving a thrust load is provided on the upper end surface of the bearing portion 6, and is disposed so as to slide directly on the flange portion of the shaft 7.

  A portion of the shaft 7 located in the bearing portion 6 is provided with a spiral groove 14 having a lead in a direction in which the lubricating oil 17 is guided upward when the shaft 7 rotates forward. The spiral groove 14 has a lower end communicating with the centrifugal pump 12 through the communication hole 13, and an upper end having an annular oil groove 16 formed by a gap between the chamfer provided at the upper end of the bearing portion 6 of the cylinder block 3 and the shaft 7. Communicating with

  The oil supply passage 15 provided in the eccentric shaft portion 9 has a lower end communicating with the annular oil groove 16 and an upper end opening in a space in the sealed container 1.

  The operation of the conventional hermetic compressor configured as described above will be described below.

  When the stator 18 is energized, the rotor 8 is driven to rotate, and the shaft 7 rotates accordingly. As a result, the piston 10 engaged through the eccentric shaft portion 9 and the slider 11 reciprocates, whereby a known compression operation is performed.

  At this time, the lubricating oil 17 rises from the lower end of the shaft 7 due to the centrifugal force acting in the centrifugal pump 12, is supplied from the communication hole 13 to the spiral groove 14, and the upward conveying force is urged by the spiral groove 14. Is done. At this time, the lubricating oil 17 forms an oil film on the sliding surfaces of the bearing portion 6 and the shaft 7 and prevents wear by avoiding metal contact.

  The lubricating oil 17 conveyed further upward is supplied to the annular oil groove 16, and a part thereof is discharged to the space in the sealed container 1 through the oil supply passage 15. In addition, a part of the lubricating oil 17 is guided to the compression element 2, and an oil film is formed on each sliding portion of the compression element 2 to avoid metal contact, thereby preventing wear and improving reliability. Yes.

Further, in a compressor, a configuration is known in which a thrust member is provided with a support member having an elastic force in a gravitational direction in a part of a thrust ball bearing, so that even when the shaft is inclined with respect to the axis, the one-side contact is prevented (for example, , See Patent Document 2).

Japanese Patent Publication No.62-44108 JP 2010-112249 A

  However, in the above conventional configuration, the reaction force of the piston load is applied to the eccentric shaft portion of the shaft in the compression process during operation. Further, since the shaft and the bearing portion have a clearance of 10 to 30 μm, the shaft is inclined.

  Therefore, in the conventional configuration, in the compression process, the influence of the piston load is added to the thrust sliding portion in addition to the weight of the shaft and the rotor, so that the surface pressure of the thrust sliding portion increases locally, so-called per contact. Therefore, there is a problem that it is not easy to maintain a smooth sliding state and to suppress sliding portion wear.

  In addition, the configuration of Patent Document 2 is configured such that the thrust ball bearing is composed of four parts: a plurality of balls, a cage for holding the balls, an upper race disposed above and below the balls, and a lower race. In addition to this, a support member is required, and there are problems of assembly and cost.

  The present invention solves the above-described conventional problems, and maintains a stable sliding state and eliminates sliding portion wear by eliminating the per-thrust of the sliding portion of the thrust. An object is to provide an efficient and low-cost hermetic compressor.

  In order to solve the above conventional problems, the hermetic compressor of the present invention is formed on a main bearing that supports the main shaft portion of the shaft and a shaft that supports a vertical load due to the weight of the rotor and the shaft. A collar part and a thrust washer for the main bearing are provided, a thrust washer is provided between the collar part and the thrust surface, the thrust washer is disposed so as to abut against the collar part, and is arranged on the opposite side of the compression chamber via the shaft. Further, the thrust washer is provided with a rotation restricting means for restricting the rotation with the thrust surface, while having an elastic force in the gravity direction over the entire circumference and arranged so as to contact the thrust surface.

  With this configuration, the number of parts is increased by only one part, and there is no contact of the thrust sliding part, so that a stable sliding state and wear of the thrust sliding part can be suppressed.

  The hermetic compressor according to the present invention eliminates the contact of the thrust sliding portion, and can suppress wear of the sliding portion while maintaining a stable sliding state by adding a single component, and is durable It is possible to provide a high-efficiency and low-cost hermetic compressor that is excellent in performance.

1 is a longitudinal sectional view of a hermetic compressor according to Embodiment 1 of the present invention. Front view of thrust washer of hermetic compressor according to the first embodiment Sectional drawing of the thrust washer of the hermetic compressor in Embodiment 1 Sectional drawing of the thrust washer shape | molded by the substantially hemispherical shape of the hermetic type compressor in Embodiment 1 The principal part expanded sectional view of the compression element of the hermetic compressor in Embodiment 1 Compressive load change diagram of hermetic compressor in the first embodiment The principal part expanded sectional view of the electric element of the hermetic compressor in Embodiment 1 Vertical section of a conventional hermetic compressor

  The invention according to claim 1 stores lubricating oil in an airtight container, accommodates an electric element including a stator and a rotor, and a compression element driven by the electric element. A shaft having an eccentric shaft portion formed through a main shaft portion and a flange portion and having a rotor fixed thereto, a cylinder block having a cylindrical compression chamber, and a piston reciprocating in the compression chamber; A coupling mechanism that couples the piston and the eccentric shaft portion; a main bearing that is formed on the cylinder block and that supports the main shaft portion of the shaft; and that is formed on the shaft, and is a weight of the rotor and the shaft. And a thrust part disposed on the upper part of the main bearing, and further provided with a thrust washer between the collar part and the thrust surface. The thrust washer is disposed so as to abut against the flange portion, and has an elastic force in the gravity direction over the entire circumference on the opposite side portion of the compression chamber via the shaft so as to abut against the thrust surface. While being arranged, the thrust washer is provided with a rotation restricting means for restricting rotation with the thrust surface.

  By adopting such a configuration, in addition to the weight of the shaft and the rotor, a piston load is applied, and even when the shaft is tilted, the upper end surface of the thrust washer that has elasticity following the tilt and the entire flange of the shaft Will come into contact. For this reason, there is no contact of the thrust sliding part, it is possible to maintain a smooth sliding state, suppress wear of the thrust sliding part, and further support by adding only a thrust washer. It is possible to provide a highly efficient and low cost hermetic compressor excellent in performance.

  According to a second aspect of the present invention, in the first aspect of the present invention, a hemispherical portion having a substantially hemispherical cross section is provided on the thrust washer on the side of the thrust washer that contacts the collar portion of the shaft. It is provided over the entire circumference.

  Accordingly, since the flange portion of the shaft and the hemispherical portion of the thrust washer are in contact with each other only by linear contact, the sliding area can be reduced, and the slidability can be improved. In addition to the effect of the present invention, higher reliability can be obtained.

  The invention according to claim 3 is the invention according to claim 1 or 2, wherein the surface of the thrust washer is subjected to nitriding treatment or ceramic coating such as CrN or TiN.

  As a result, the low coefficient of friction and the wear resistance can be improved, and in addition to the effects of the invention according to claim 1 or claim 2, higher reliability can be obtained.

  According to a fourth aspect of the present invention, in the invention according to any one of the first to third aspects, the electric element has a relative position of a magnetic center of a rotor with respect to a magnetic center of the stator. It is configured to be downward.

  As a result, during operation of the compressor, a force that pulls up the shaft fixed to the rotor by the magnetic attraction force acts, so that the vertical load due to the weight of the rotor and the shaft is reduced. In addition to the effects described in any one of claims 1 to 3, the frictional force of the sliding portion is reduced, and higher reliability can be obtained.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 is a longitudinal sectional view of a hermetic compressor according to the first embodiment of the present invention, FIG. 2 is a front view of a thrust washer of the hermetic compressor according to the first embodiment, and FIG. 4 is a cross-sectional view of a thrust washer of the hermetic compressor in FIG. 1, FIG. 4 is a cross-sectional view of a thrust washer (modified example) formed in a substantially hemispherical shape of the hermetic compressor in Embodiment 1, and FIG. FIG. 6 is an enlarged cross-sectional view of the main part of the compression element of the hermetic compressor in the first embodiment, FIG. 6 is a diagram showing changes in compression load of the hermetic compressor in the first embodiment, and FIG. 7 is a hermetic seal in the first embodiment. It is a principal part expanded sectional view of the electric element of a type | mold compressor.

  In FIGS. 1 to 7, lubricating oil 102 is stored in an airtight container 101, and an electric element 105 having a stator 103 and a rotor 104, and driven by the electric element 105, above the electric element 105. A compression element 106 disposed in the housing.

  A shaft 110 constituting the compression element 106 includes a main shaft portion 111 on which the rotor 104 is shrink-fitted and fixed, and an eccentric shaft portion 113 formed eccentrically with respect to the main shaft portion 111 via a flange portion 112. An oil supply mechanism 114 is provided inside.

  The cylinder block 115 has a substantially cylindrical compression chamber 116, and a main bearing 117 that supports the main shaft portion 111 is formed. The piston 118 is inserted into the compression chamber 116 of the cylinder block 115 so as to be slidable back and forth, and is connected to the eccentric shaft portion 113 by a connecting mechanism 119 and a piston pin 120.

  A thrust washer 122 is disposed between the flange portion 112 of the shaft 110 and the thrust surface 121 which is the upper end surface of the main bearing 117, and supports a vertical load due to the weight of the rotor 104 and the shaft 110. . The thrust washer 122 is disposed so as to contact the flange portion 112, and has an elastic force in the gravity direction over the periphery (half circumference) of the opposite side portion 116a of the compression chamber via the shaft 110, and is elastically bent. It is sometimes arranged so as to contact the thrust surface 121 as well. The thrust washer 122 is provided with a rotation restricting means 123 that restricts the rotation with the thrust surface 121.

  The electric element 105 is a concentrated winding type in which windings are concentratedly wound around a tooth portion provided in the core of the stator 103. Further, as shown in FIG. 7, the relative position of the rotor magnetic center 128 of the rotor 104 is shifted downward with respect to the stator magnetic center 127 of the stator 103 constituting the electric element 105. .

  The operation and action of the hermetic compressor configured as described above will be described below.

  The rotor 104 of the electric element 105 rotates the shaft 110, and the rotational motion of the eccentric shaft portion 113 is transmitted to the piston 118 via the coupling mechanism 119, so that the piston 118 reciprocates within the compression chamber 116.

  Thereby, the refrigerant gas is sucked into the compression chamber 116 from the cooling system (not shown), compressed, and then discharged to the cooling system again.

At this time, a vertical load due to the weight of the rotor 104 and the shaft 110 acts on the thrust surface 121, the thrust washer 122, and the flange portion 112 formed in the cylinder block 115, and the vertical direction due to the influence of the piston 118 load. The load of is acting locally.

  Next, the load in the vertical direction due to the influence of the piston 118 load will be described.

  The compression load F1 acting on the piston 118 is governed by the pressure in the compression chamber 116 and the inner diameter of the compression chamber 116, and becomes maximum near 330 deg in the latter half of the compression stroke, as shown in FIG. Act on.

  In the latter half of the compression stroke in which the maximum compressive load is generated, the eccentric shaft portion 113 is positioned on the compression chamber 116 side, and the compression load F1 acting on the piston 118 acts on the eccentric shaft portion 113 via the coupling mechanism 119.

  Further, since the main shaft portion 111 and the main bearing 117 of the shaft 110 have a clearance of about 10 to 30 μm, the shaft 110 is inclined and, as shown in FIG. 5, due to the compressive load F1 acting on the eccentric shaft portion 113, A load F2 in the vertical direction of the compression load F1 acts on the thrust washer 122 on the opposite side 116a of the compression chamber via the shaft 110.

  Therefore, in the latter half of the compression stroke, the piston 118 load is applied in addition to the own weight of the shaft 110 and the rotor 104, so that the thrust washer 122 having an elastic force also follows the inclination of the shaft 110. In this state, the upper end surface of the thrust washer 122 and the entire flange portion 112 of the shaft 110 are in contact with each other, so there is no contact of the sliding portion, and the smooth sliding state is maintained and the sliding portion wear is suppressed. In addition, since it becomes possible to cope with this by adding only the thrust washer 122, it is possible to provide a highly efficient and low cost hermetic compressor with excellent durability.

  Further, as shown in FIG. 4, a hemispherical portion 126 having a substantially hemispherical cross section may be provided on the thrust washer 122 on the side in contact with the flange portion 112 of the shaft 110 as shown in FIG.

  According to this configuration, since the flange portion 112 of the shaft 110 and the hemispherical portion 126 of the thrust washer 122 are in contact with each other only by line contact, the sliding area can be reduced and the slidability is improved.

  Further, by applying nitriding treatment or ceramic coating such as CrN or TiN to the surface of the thrust washer 122, the wear resistance is improved by low friction and high hardness, and higher reliability can be obtained.

  Further, the electric element 105 is provided with the rotor 104 so that the relative position of the rotor magnetic center 128 in the vertical direction of the rotor 104 is shifted downward with respect to the stator magnetic center 127 in the vertical direction of the stator 103. doing. As a result, a force that pulls up the shaft 110 fixed to the rotor 104 by the magnetic attraction force acts, so that the vertical load due to the weight of the rotor 104 and the shaft 110 is reduced. Therefore, the load in the vertical direction applied to the flange portion 112 and the thrust washer 122 of the shaft 110 is reduced, and higher reliability can be obtained.

  In the first embodiment, the compression element 106 is arranged at the upper part and the electric element 105 is arranged at the lower part. However, the electric element 105 is arranged at the upper part and the compression element 106 is arranged at the lower part. The same effect can be obtained with the hermetic compressor provided.

  As described above, the hermetic compressor according to the present invention improves the slidability and durability of the shaft flange and the thrust washer, and provides high reliability. Therefore, the hermetic compressor of the air conditioner and the refrigerator / freezer is sealed. Applicable to mold compressor applications.

DESCRIPTION OF SYMBOLS 101 Airtight container 102 Lubricating oil 103 Stator 104 Rotor 105 Electric element 106 Compression element 110 Shaft 111 Main shaft part 112 Head part 113 Eccentric shaft part 115 Cylinder block 116 Compression chamber 116a Opposite part of compression chamber 117 Main bearing 118 Piston 119 Connection Mechanism 121 Thrust surface 122 Thrust washer 123 Rotation restricting means 127 Stator magnetic center 128 Rotor magnetic center 126 Hemispherical portion

Claims (4)

Lubricating oil is stored in a sealed container, and an electric element having a stator and a rotor and a compression element driven by the electric element are accommodated, and the compression element is formed via a main shaft part and a flange part. A shaft having an eccentric shaft portion and having a fixed rotor, a cylinder block having a cylindrical compression chamber, a piston reciprocating in the compression chamber, and the piston and the eccentric shaft portion are connected to each other. A coupling mechanism, a main bearing formed on the cylinder block and supporting the main shaft portion of the shaft, and a flange formed on the shaft and supporting a vertical load due to the weight of the rotor and the shaft. And a thrust surface disposed on an upper portion of the main bearing, and further, a thrust washer is provided between the flange portion and the thrust surface, and the thrust washer is It is arranged so as to abut against the flange part, and has an elastic force in the direction of gravity over the entire circumference on the opposite side of the compression chamber via the shaft, and is arranged so as to abut against the thrust surface as well. A hermetic compressor in which a thrust washer is provided with rotation regulating means for regulating rotation with the thrust surface. 2. The hermetic compressor according to claim 1, wherein a hemispherical portion having a substantially hemispherical cross section is provided over the entire circumference of the thrust washer on a side of the thrust washer that contacts the collar portion of the shaft. The hermetic compressor according to any one of claims 1 and 2, wherein a surface of the thrust washer is subjected to nitriding treatment or ceramic coating such as CrN or TiN. The hermetic compressor according to any one of claims 1 to 3, wherein the electric element is configured such that a relative position of a magnetic center of a rotor is downward with respect to a magnetic center of the stator.