JP2013133758A - Hermetic compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high-efficiency and highly-reliable hermetic compressor with low cost and compact size by reducing the abrasion of a thrust ball bearing.SOLUTION: The hermetic compressor includes a second inclined portion 114 provided on a balance weight 115 and a first inclined portion 112 provided on a collar portion 113. Accordingly, gas is received by the second inclined portion and first inclined portion 112, whereby two directional forces of vertically downward and horizontal forces are generated in the first inclined portion 112 and the second inclined portion 114, and a vertically downward force is worked on the thrust ball bearing 140 by use of the vertical downward force of the component of the two forces, in addition to a vertical downward load by the own weights of a rotator 104 and a shaft 110, whereby the sliding of a ball 142 can be reduced. Thus, the abrasion of the thrust ball bearing 140 is reduced, whereby high reliability of the compact hermetic compressor can be secured with a compact size.

Description

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

  In recent years, high efficiency is being promoted for hermetic compressors used in refrigeration apparatuses such as refrigerators and refrigerators to reduce power consumption. Conventionally, thrust ball bearings that reduce the sliding loss of a thrust bearing portion as compared with a slide bearing have been adopted as a means for improving efficiency.

  As a conventional hermetic compressor of this type, there is one that achieves high efficiency by using a thrust ball bearing having a low-cost and simple structure that uses a polymer material cage, with the top and bottom of the ball sandwiched between washers. (For example, refer to Patent Document 1).

  Hereinafter, the conventional hermetic compressor will be described with reference to the drawings.

  FIG. 3 is a longitudinal sectional view of a conventional hermetic compressor described in Patent Document 1. As shown in FIG.

  As shown in FIG. 3, in the sealed container 1, an electric element 4 having a stator 2 and a rotor 3 and a compression element 5 driven by the electric element 4 are accommodated, and the sealed container 1 is lubricated. Oil 6 is stored. The shaft 10 has a main shaft portion 11 to which the rotor 3 is fixed and an eccentric shaft portion 12 that is formed eccentric to the main shaft portion 11.

  The cylinder block 14 includes a substantially cylindrical compression chamber 15 and a main bearing 20. The piston 23 is inserted into the compression chamber 15 of the cylinder block 14 so as to be slidable back and forth, and is connected to the eccentric shaft portion 12 by a connecting means 24 and a piston pin 25.

  An annular upper washer seating surface 27 is formed on the main shaft portion 11 side between the main shaft portion 11 and the eccentric shaft portion 12 of the shaft 10 at a substantially right angle to the shaft center of the main shaft portion 11. An annular lower washer seating surface 28 is formed substantially at right angles to the 20 axis.

  A thrust ball bearing 29 is provided between the upper washer seating surface 27 and the lower washer seating surface 28 to support the load in the gravity direction of the shaft 10 and the rotor 3.

  The thrust ball bearing 29 includes a plurality of balls 30, a cage 31 made of a polymer material typified by nylon that holds the balls 30, and an upper washer 32 and a lower washer respectively disposed above and below the ball 30. 33. The upper washer 32 and the lower washer 33 are formed of hardened iron flat plates.

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

  The rotor 3 of the electric element 4 rotates the shaft 10, and the rotational movement of the eccentric shaft portion 12 is transmitted to the piston 23 via the connecting means 24, so that the piston 23 reciprocates in the compression chamber 15. Thereby, the refrigerant gas is sucked into the compression chamber 15 from the cooling system (not shown), compressed, and then discharged to the cooling system again.

The weight of the shaft 10 and the rotor 3 is supported by a thrust ball bearing 29. When the shaft 10 rotates, the ball 30 rolls between the upper washer 32 and the lower washer 33, so that the shaft 10 rotates smoothly.

  During the rotation of the shaft 10, the upper washer 32 is in close contact with the upper washer seating surface 27, and the lower washer 33 is in close contact with the lower washer seating surface 28. The cage 31 holds the ball 30 so that the ball 30 does not jump out due to centrifugal force.

  By using this thrust ball bearing 29, the torque for rotating the shaft 10 is smaller than that of the thrust slide bearing, so that the loss in the thrust bearing can be reduced. Therefore, the input can be reduced and the efficiency can be improved.

JP 2005-127305 A

  However, in the above-described conventional configuration, if the weight of the rotor and the shaft is small, the ball may slide against the upper washer or the lower washer, and the ball, the upper washer, and the lower washer are worn and reliability is lowered. Had the potential to end up.

  The present invention solves the above-mentioned conventional problems, and provides a low-cost, compact and highly reliable hermetic compressor by applying a downward load to the thrust ball bearing using the rotational force of the shaft. The purpose is to do.

  In order to solve the above-described conventional problems, the hermetic compressor of the present invention is provided with an inclined portion in the flange portion formed on the balance weight and the shaft, and the gas sealed in the hermetic container is rotated by the shaft. As a result, the balance weight and the inclined portion provided on the flange portion formed on the shaft receive the force in the vertical direction and the vertical direction of the two force components in the vertical direction. A downward load in the vertical direction acts on the thrust ball bearing using the downward force in the direction, so that the slip between the ball, the upper washer, and the lower washer can be reduced, and the wear of the thrust ball is reduced.

  The hermetic compressor of the present invention can obtain a vertically downward load on the thrust ball bearing without increasing the weight of the rotor and the shaft while maintaining the effect of reducing the sliding loss of the thrust bearing portion. Therefore, it is possible to provide a low-cost, compact and highly reliable hermetic compressor.

1 is a longitudinal sectional view of a hermetic compressor according to Embodiment 1 of the present invention. Cross-sectional view of the main part in the same embodiment Vertical section of a conventional hermetic compressor

According to a first aspect of the present invention, lubricating oil is stored in an airtight 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 has a main shaft portion and a flange. An eccentric shaft portion provided with a balance weight, a shaft to which the rotor is fixed, a cylinder block having a cylindrical compression chamber, and a piston that reciprocates 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 supports the main shaft portion of the shaft, and a vertical load caused by the weight of the rotor and the shaft. A thrust ball bearing for supporting the shaft, and a first inclined portion formed on the flange portion provided on the shaft and a second inclined portion formed on the balance weight. That.

  As a result, by receiving the gas sealed in the sealed container at the first inclined portion and the second inclined portion provided on the balance weight and the flange portion formed on the shaft as the shaft rotates, the first inclined portion and A force in two directions, a vertical downward direction and a horizontal direction, is generated in the second inclined portion, and a vertical downward load is applied to the thrust ball bearing by using the vertical downward force of the two force components. Therefore, it is possible to provide a low-cost, compact and highly reliable hermetic compressor by reducing the sliding between the ball, the upper washer, and the lower washer, and reducing the wear of the thrust ball bearing. .

  2nd invention provides the oil supply hole and oil supply path which were opened to the end of the 1st inclination part and the 2nd inclination part which were provided in the collar part and the balance weight, and in addition to gas, specific gravity is larger than gas Lubricating oil is also received by the flange portion formed on the shaft as the shaft rotates, and the first inclined portion and the second inclined portion provided on the balance weight, so that the first inclined portion and the second inclined portion are further perpendicular to each other. A downward force is generated, the vertical downward load applied to the thrust ball bearing is increased, and higher reliability can be obtained.

  In a third aspect of the present invention, a first wall and a second wall are provided at the side ends of the first inclined portion and the second inclined portion provided in the flange portion and the balance weight, and formed on the shaft as the shaft rotates. Since the gas and the lubricating oil received by the first inclined portion and the second inclined portion provided on the flange portion and the balance weight can be received more, the first inclined portion and the second inclined portion are further directed vertically downward. A force is generated, the vertical downward load applied to the thrust ball bearing is increased, and higher reliability can be obtained.

  In the fourth invention, the first inclined portion and the inclined surface of the second inclined portion provided on the flange portion and the balance weight are formed to be curved, and lubrication received by the first inclined portion and the second inclined portion. The oil travels along a curved inclined surface and is sprayed on the upper part of the closed container, so that the lubricating oil adheres to the surface of more closed containers, so that the hot lubricating oil exchanges more heat with the closed containers. When the temperature of the lubricating oil is reduced, the temperature of the whole hermetic compressor is reduced, and high efficiency and high reliability can be obtained.

  In the fifth aspect of the invention, the third inclined portion is provided at the lower end portion of the shaft immersed in the lubricating oil, and more lubricating oil having a specific gravity than gas can be received by the third inclined portion. A downward force in the vertical direction is generated, and the downward load applied to the thrust ball bearing is increased, so that higher reliability can be obtained.

  According to a sixth aspect of the invention, the electric element is driven at a plurality of operating frequencies by an inverter, and the rotor is rotated at a rotation frequency of at least 60 Hz, and the first inclined portion per one rotation as the number of rotations increases. Since the amount of gas and lubricating oil received at the second inclined part and the third inclined part increases, the downward load on the thrust ball bearing also increases with high speed operation. As well as optimal operation of the refrigeration cycle by high-speed operation.

  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, and FIG. 2 is a main part sectional view of the hermetic compressor according to the first embodiment.

  In FIGS. 1 and 2, lubricating oil 102 is stored in a sealed container 101, and an electric element 105 including a stator 103 and a rotor 104, and driven by the electric element 105, above the electric element 105. Houses the disposed compression element 106.

  A shaft 110 constituting the compression element 106 is formed eccentrically with respect to the main shaft portion 111 via a main shaft portion 111 on which the rotor 104 is shrink-fitted and fixed, and a flange portion 113 having a first inclined portion 112. An eccentric shaft portion 116 in which a balance weight 115 having an inclined portion 114 is inserted, and a third inclined portion 117 is provided outside the lower end of the shaft 110 to constitute an oil supply mechanism 118 inside. The first inclined portion 112 includes a first wall 112A and the second inclined portion 114 includes a second wall 114A.

  The cylinder block 120 has a substantially cylindrical compression chamber 121, and a main bearing 122 that supports the main shaft portion 111 is formed. The piston 130 is inserted into the compression chamber 121 of the cylinder block 120 so as to be slidable back and forth, and is connected to the eccentric shaft portion 116 by a connecting mechanism 131 and a piston pin 132.

  The thrust ball bearing 140 is disposed between the flange portion 113 and the upper end surface 141 of the main bearing 122 and supports a downward load in the vertical direction due to the weight of the rotor 104 and the shaft 110.

  The thrust ball bearing 140 includes a plurality of balls 142, a holder portion 143 that holds the balls 142, and an upper washer 144 and a lower washer 145 that are respectively disposed above and below the ball 142.

  The shaft 110 is provided with an oil supply mechanism 118, a spiral groove 150, an oil supply hole 151, and an oil supply passage 152 as a passage for conveying the lubricating oil 102 stored in the lower portion of the sealed container 101 upward.

  The electric element 105 is a concentrated winding type electric element 105 in which a winding is concentratedly wound on a tooth portion provided in a core of the stator 103. Further, the electric element 105 can be operated to be rotated at a rotational frequency of at least 60 Hz at a plurality of rotational speeds by inverter control, and the maximum rotational speed is 80 Hz.

  The operation 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 movement of the eccentric shaft portion 116 is transmitted to the piston 130 via the coupling mechanism 131, so that the piston 130 reciprocates in the compression chamber 121. Thereby, the refrigerant gas is sucked and compressed from the cooling system (not shown) into the compression chamber 121 and then discharged again to the cooling system.

  Further, the lubricating oil 102 stored in the lower portion of the sealed container 101 is conveyed to the upper portion by the oil supply mechanism 118 provided inside the lower end of the shaft 110 and reaches one end of the spiral groove 150 as the shaft 110 rotates. The lubricating oil 102 that has reached one end of the spiral groove 150 is conveyed to the oil supply hole 151 through the spiral groove 150, and a part of the lubricating oil 102 is conveyed to the first inclined portion 112 through the oil supply hole 151, and the remaining The lubricating oil 102 is further conveyed to the upper portion through the oil supply passage 152, discharged from the upper end portion of the eccentric shaft portion 116, attached to the inner surface of the upper portion of the sealed container 101 through the second inclined portion 114, and sealed container 101. And heat exchange.

  At this time, the thrust ball bearing 140 disposed between the flange portion 113 and the upper end surface 141 of the main bearing 122 receives the vertical downward load while the ball 142 is positioned between the upper washer 144 and the lower washer 145. Sliding loss is reduced by rolling smoothly.

  As described above, in the present embodiment, the closed container 101 is provided by including the second inclined portion 114 provided on the balance weight 115 and the first inclined portion 112 provided on the flange portion 113 formed on the shaft 110. By receiving the gas enclosed in the second inclined portion provided in the balance weight 115 and the first inclined portion 112 provided in the flange 113 formed in the shaft 110 as the shaft 110 rotates, the first inclined portion is provided. 112 and the second inclined portion 114 generate forces in two directions of vertical downward and horizontal, and the thrust ball bearing 140 uses the vertical downward force of the two force components to provide a rotor. In addition to the vertical downward load due to the weight of the shaft 104 and the shaft 110, a downward force in the vertical direction acts on the ball 142 and the upper washer 144. Can be reduced slippage and Ssha 145, to reduce the wear of the thrust ball bearing 140, it is possible to provide a low-cost, compact and reliable hermetic compressor.

  Further, in the present embodiment, by providing the oil supply hole 151 opened at one end of the second inclined portion provided on the balance weight 115 and the first inclined portion 112 provided on the flange portion 113 formed on the shaft 110, The lubricating oil 102 stored in the lower part of the sealed container 101 is conveyed to the upper part by the oil supply mechanism 118, and part of the lubricating oil 102 is conveyed to the first inclined portion 112 through the oil supply hole 151 through the spiral groove 150, The remaining lubricating oil 102 is further conveyed to the upper portion through the oil supply passage 152, and the lubricating oil 102 is conveyed from the upper end of the eccentric shaft portion 116 to the second inclined portion 114, whereby the lubricating oil 102 having a larger specific gravity than the gas. Can be received by the first inclined portion 112 and the second inclined portion 114, and further, a downward force in the vertical direction acts on the thrust ball bearing 140. 42 and the upper washer 144, can be reduced slippage between the lower washer 145, to reduce the wear of the thrust ball bearing 140, it is possible to provide a low-cost, compact and reliable hermetic compressor.

  Moreover, in this Embodiment, the 1st wall 112A and the 2nd wall 114A were each provided in the side edge of the 1st inclination part 112 and the 2nd inclination part 114 which were provided in the balance weight 115 and the collar part 113. As the shaft 110 rotates, the balance weight 115 and the gas and the lubricating oil 102 received by the first inclined portion 112 and the second inclined portion 114 provided on the flange portion 113 formed on the shaft 110 can be received more. In addition, since the downward force in the vertical direction acts on the thrust ball bearing 140, the sliding between the ball 142, the upper washer 144, and the lower washer 145 can be further reduced, and the wear of the thrust ball bearing 140 can be reduced. A compact and highly reliable hermetic compressor can be provided.

  Further, in the present embodiment, the inclined surfaces of the first inclined portion 112 and the second inclined portion 114 provided on the balance weight 115 and the flange portion 113 are formed by being curved. The lubricating oil 102 received by the two inclined portions 114 travels along the curved inclined surface, and is sprayed onto the upper portion of the sealed container 101, and the lubricating oil 102 adheres to the surface in a larger number of the sealed containers 101. More heat exchange is performed between the lubricating oil 102 and the sealed container 101, and the temperature of the lubricating oil 102 is reduced, so that the temperature of the whole hermetic compressor is reduced and high reliability can be obtained with high efficiency. it can.

Further, in the present embodiment, the third inclined portion 117 is provided at the lower end portion of the shaft 110 immersed in the lubricating oil 102, and more lubricating oil 102 having a specific gravity larger than that of the gas is increased by the third inclined portion 117. Since the vertical downward force further acts on the thrust ball bearing 140, the sliding between the ball 142, the upper washer 144, and the lower washer 145 can be further reduced, and the wear of the thrust ball bearing 140 is reduced. Thus, a low-cost, compact and highly reliable hermetic compressor can be provided.

  Further, in the present embodiment, the electric element 105 is driven by an inverter at a plurality of operating frequencies, and the rotor 104 is rotated at a rotation frequency of at least 60 Hz. Since the amount of the gas and the lubricating oil 102 received by the first inclined portion 112, the second inclined portion 114, and the third inclined portion 117 increases, the downward load applied to the thrust ball bearing 140 in accordance with the high speed operation is also increased. Therefore, the vertical downward force acts on the thrust ball bearing 140 to further reduce the sliding between the ball 142, the upper washer 144, and the lower washer 145, and to reduce the wear of the thrust ball bearing 140. Thus, a low-cost, compact and highly reliable hermetic compressor can be provided.

  As described above, the hermetic compressor according to the present invention can reduce the wear of the thrust ball bearing while maintaining the effect of reducing the sliding loss of the thrust bearing portion and the compactness. It can be applied to the use of a hermetic compressor of a refrigeration apparatus.

DESCRIPTION OF SYMBOLS 101 Sealed container 102 Lubricating oil 103 Stator 104 Rotor 105 Electric element 106 Compression element 110 Shaft 111 Main shaft part 112 First inclined part 112A First wall 113 Collar part 114 Second inclined part 114A Second wall 115 Balance weight 116 Eccentric shaft Portion 117 Third inclined portion 120 Cylinder block 121 Compression chamber 122 Main bearing 130 Piston 131 Connection mechanism 140 Thrust ball bearing 151 Oil supply hole 152 Oil supply passage

Claims (6)

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 through a main shaft part and a flange part. An eccentric shaft portion provided with a balance weight, a shaft to which the rotor is fixed, a cylinder block having a cylindrical compression chamber, a piston reciprocating in the compression chamber, the piston, and the piston A coupling mechanism that couples the eccentric shaft portion, a main bearing that is formed on the cylinder block and supports the main shaft portion of the shaft, and a thrust ball bearing that supports a load in the vertical direction due to the weight of the rotor and the shaft. A hermetic compressor including a first inclined portion formed in a flange portion provided in the shaft and a second inclined portion formed in the balance weight. 2. The hermetic compressor according to claim 1, wherein an oil supply hole and an oil supply passage that are open at least at one end of the first inclined part and the second inclined part are provided. The hermetic compressor according to claim 1 or 2, wherein a first wall and a second wall are provided at side ends of the first inclined portion and the second inclined portion, respectively. The hermetic compressor according to any one of claims 1 to 3, wherein the inclined surfaces of the first inclined portion and the second inclined portion are curved. The hermetic compressor according to any one of claims 1 to 4, wherein a third inclined portion is provided at a lower end portion of the shaft immersed in the lubricating oil. The hermetic compressor according to any one of claims 1 to 5, wherein the electric element is driven by an inverter at a plurality of operating frequencies, and the rotor is rotated at a rotational frequency of at least 60 Hz.

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