JP2008002371A - Hermetic compressor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain low noise and high reliability by adsorbing one-sided contact or an impact load of a ball even if washer bearing surfaces are slightly inclined or when the impact load is applied during transportation or the like. <P>SOLUTION: At least one of an upper washer 138 and a lower washer 139 is resiliently supported. Even if the upper washer bearing surface 131 or the lower washer bearing surface 132 is slightly inclined, a track portion for the balls 135 at the lower washer 139 is shifted to absorb a precision error and a clearance between the upper washer 138 and the lower washer 139 is kept almost uniform. A load is therefore not concentrated on a particular ball 135 and dispersed to the respective balls 135 and one-sided contact of the balls 135 is decreased. The lower washer 139 which is resiliently supported absorbs an impact even if the impact load is applied. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

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

  In recent years, with regard to hermetic compressors used in refrigeration apparatuses such as refrigerators and refrigerators, high efficiency, low noise, and high reliability for reducing power consumption are desired.

  Conventionally, this type of hermetic compressor employs a thrust ball bearing to improve efficiency (for example, see Patent Document 1).

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

  FIG. 4 is a longitudinal sectional view of a conventional hermetic compressor described in Patent Document 1, and FIG. 5 is an exploded perspective view of main parts. As shown in FIGS. 4 and 5, the hermetic container 1 contains an electric element 4 including a stator 2 and a rotor 3, and a compression element 5 driven by the electric element 4. The lubricating 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. Between the upper washer seating surface 27 and the lower washer seating surface 28, a thrust ball bearing 35 comprising a ball 30, an upper washer 31, and a lower washer 32 is mounted to support the shaft 10. The upper washer 31 and the lower washer 32 are formed of 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 the thrust ball bearing 35, and the rotation of the shaft 10 is smooth because the ball 30 rolls between the upper washer 31 and the lower washer 32 when the shaft 10 rotates. During rotation, the upper washer 31 is in close contact with the upper washer seating surface 27 and rotates simultaneously with the upper washer seating surface 27, and the lower washer 32 is in close contact with the lower washer seating surface 28 and is stationary. By using this thrust ball bearing 35, the torque for rotating the shaft 10 is smaller than that of the thrust slide bearing, so that the loss at the thrust bearing can be reduced. Therefore, the input can be reduced and the efficiency can be improved.
JP 2005-127305 A

  However, with the above conventional configuration, noise and efficiency may vary with the same design specifications. Thus, when a noisy hermetic compressor was disassembled and investigated, there was a sign that a peeling phenomenon occurred in a part of the upper washer 31 and the lower washer 32.

  Furthermore, as a result of investigating the correlation between the machining accuracy of each component, noise, and efficiency, when the perpendicularity between the upper washer seating surface 27 and the shaft center of the main shaft portion 11 is poor, the lower washer seating surface 28 and the main bearing 20 It has been found that when the perpendicularity to the shaft center is bad, the above phenomenon occurs, and noise and efficiency deteriorate.

  That is, when the perpendicularity between the upper washer seating surface 27 and the main shaft portion 11 is bad, or when the perpendicularity between the lower washer seating surface 28 and the main bearing 20 is bad, the upper washer 31 and the lower washer 32 are not parallel. Since the gaps into which the balls 30 enter are uneven, the loads are not evenly applied to the respective balls 30, and the loads are concentrated on the balls 30 passing through the narrow gaps, and the balls 30, the upper washers 31 and the lower washers 32 are excessively loaded. It has been found that damages such as peeling due to fatigue are caused by repeated repeated stresses, which may reduce noise, efficiency, and reliability.

  Further, the clearance between the upper washer seating surface 27 and the lower washer seating surface 28 is formed with a margin so that the shaft 10 can be slightly moved up and down to make the rotation smooth. Therefore, the shaft 10 moves up and down due to vibrations applied from the outside during transportation of the hermetic compressor, and an impact load is applied to the ball 30, and damage to the ball 30, the upper washer 31 and the lower washer 32, such as dents. It had the problem that it could occur.

  SUMMARY OF THE INVENTION The present invention solves the above-described conventional problems, and an object thereof is to provide a hermetic compressor with low noise, high efficiency, and high reliability by alleviating ball hitting and impact load.

  In order to solve the above-described conventional problems, the hermetic compressor of the present invention is characterized in that at least one of the upper washer and the lower washer that is in contact with the ball is elastically supported. When the perpendicularity between the washer seating surface and the main shaft is poor, or when the perpendicularity between the lower washer seating surface and the main bearing is bad, the ball raceway on the washer displaces to absorb the accuracy error, and the upper washer and lower Since the gap between the washers is kept almost uniform, the load is not concentrated on a specific ball, but the load is distributed to each ball to reduce the contact between the balls and is elastic even when an impact load is applied to the ball. The supported washer has a function of mitigating impact.

  The hermetic compressor according to the present invention distributes the load to each ball, relaxes the impact of the ball on one piece, and reduces the impact load applied to the ball during transportation, etc. A reliable hermetic compressor can be provided.

  According to the first aspect of the present invention, lubricating oil is stored in an airtight container and an electric element and a compression element driven by the electric element are accommodated, and the compression element has an eccentric shaft portion and a main shaft portion. A cylinder block having a substantially cylindrical compression chamber, a piston that reciprocates in the compression chamber, connection means for connecting the piston and the eccentric shaft portion, and the cylinder block formed on the shaft. A main bearing that pivotally supports the main shaft, an upper washer seating surface that is provided on the shaft and substantially perpendicular to the axis of the main shaft, and a substantially right angle to the axis of the main bearing provided on the main bearing A lower washer seating surface provided, and a thrust ball bearing provided between the upper washer seating surface and the lower washer seating surface, the thrust ball bearing comprising a plurality of balls and the ball A holder portion for holding the handle and an upper washer and a lower washer respectively disposed above and below the ball, and at least one of the upper washer or the lower washer is elastically supported. When the perpendicularity between the washer seating surface and the main shaft is poor, or when the perpendicularity between the lower washer seating surface and the main bearing is bad, the ball raceway on the washer displaces to absorb the accuracy error, and the upper washer and lower Since the gap between the washers is kept almost uniform, the load is not concentrated on a specific ball, but the load is distributed to each ball to reduce the contact between the balls, and an impact load is applied to the ball during transportation. Even in such a case, since the elastically supported washer relieves the impact, a hermetic compressor with low noise, high efficiency and high reliability can be provided.

  According to a second aspect of the present invention, in the first aspect of the invention, an elastic member is provided between at least one of the upper washer seating surface and the upper washer or between the lower washer seating surface and the lower washer. In addition, since the upper washer and the lower washer can be the same as the conventional one and only the elastic member needs to be added, in addition to the effect of the invention described in claim 1, manufacturing and assembly can be facilitated.

  The invention according to claim 3 is the invention according to claim 1 or 2, wherein only a part of the surface of the upper washer or the lower washer not contacting the ball is supported, and the upper washer or the lower washer is supported. Since the deformation of the washer itself can be used, the effect of the invention described in claim 1 or 2 can be obtained more effectively.

  The invention according to claim 4 is the invention according to claim 2, wherein the elastic member is formed of a heat-resistant polymer material, and the elastic member does not deteriorate even under high temperature conditions. The effect of the invention of item 2 can be obtained more stably.

  The invention according to claim 5 is the invention according to any one of claims 1 to 4, wherein the lubricating oil has a viscosity of VG3 to VG8, and the loss at the sliding portion can be reduced. In addition to the effect of the invention according to any one of Items 1 to 4, the efficiency can be further increased.

  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 Embodiment 1 of the present invention, FIG. 2 is a cross-sectional view of a main part of the hermetic compressor of the same embodiment, and FIG. 3 is a hermetic seal of the same embodiment. It is a principal part disassembled perspective view of a type compressor.

  1 to 3, an airtight element 101 includes an electric element 104 including a stator 102 and a rotor 103, and a compression element 105 driven by the electric element 104, and a lubricating oil 106 is contained in the airtight container 101. To save. The shaft 110 includes a main shaft portion 111 to which the rotor 103 is fixed, and an eccentric shaft portion 112 that is disposed above the main shaft portion 111 and formed eccentric to the main shaft portion 111.

  The cylinder block 114 has a substantially cylindrical compression chamber 116, and a main bearing 120 that supports the main shaft portion 111 is fixed thereto. The piston 126 is inserted into the compression chamber 116 of the cylinder block 114 so as to be slidable back and forth, and is connected to the eccentric shaft portion 112 by a connecting means 127 and a piston pin 128.

  An upper washer seating surface 131 is formed in an annular shape on the main shaft portion 111 side between the main shaft portion 111 and the eccentric shaft portion 112 of the shaft 110 so as to be substantially perpendicular to the shaft center of the main shaft portion 111. A lower washer seating surface 132 is formed in an annular shape substantially at a right angle to the 120 axis. Between the upper washer seating surface 131 and the lower washer seating surface 132, a plurality of balls 135, a holder portion 136 for holding the balls 135, and the upper and lower sides of the balls 135 are disposed to support the shaft 110. A thrust ball bearing 140 comprising an upper washer 138 and a lower washer 139 is mounted. An elastic member 145 is provided between the lower washer seating surface 132 and the lower washer 139. Since the elastic member 145 has a larger inner and outer diameter than the lower washer 139, only the outer peripheral side of the surface of the lower washer 139 that does not contact the ball 135 is supported by the elastic member 145 in an annular shape. The elastic member 145 is made of PA66 (66 nylon) which is a heat resistant polymer material.

  The refrigerant used in the hermetic compressor is a hydrocarbon refrigerant or the like, which is a natural refrigerant with a low global warming coefficient represented by R134a or R600a having an ozone depletion coefficient of zero. In combination, the viscosity of the lubricating oil 106 is VG5.

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

  The rotor 103 of the electric element 104 rotates the shaft 110, and the rotational movement of the eccentric shaft portion 112 is transmitted to the piston 126 via the connecting means 127, so that the piston 126 reciprocates in 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.

  The weight of the shaft 110 and the rotor 103 is supported by the thrust ball bearing 140, and when the shaft 110 rotates, the ball 135 rolls between the upper washer 138 and the lower washer 139, so that the rotation becomes smooth. By using the thrust ball bearing 140, the torque for rotating the shaft 110 is smaller than that of the thrust slide bearing, so that the loss at the thrust bearing can be reduced. Therefore, the input can be reduced and the efficiency can be improved.

  At this time, the upper washer 138 is in close contact with the upper washer seating surface 131 and rotates simultaneously with the upper washer seating surface 131, the lower washer 139 is in close contact with the elastic member 145, and the elastic member 145 is in close contact with the lower washer seating surface 132. It is stationary.

  When the perpendicularity of the lower washer seating surface 132 with respect to the main bearing 120 axis is poor, that is, when the inclination of the lower washer seating surface 132 is large, the clearance between the upper washer seating surface 131 and the lower washer seating surface 132 is the conventional specification. It becomes imbalanced.

  However, in this embodiment, the elastic member 145 is deformed, and the washer supported in a cantilever manner is elastically deformed and tilted, so that the track portion of the ball 135 in the lower washer 139 is displaced to absorb the accuracy error. Therefore, the imbalance of the gap between the upper washer seating surface 131 and the lower washer seating surface 132 is alleviated, and the gap becomes close to uniform. By this action, the load is not concentrated on the specific ball 135, but the load is distributed to each ball 135, the one-sided contact of the ball 135 is relaxed, and the ball rotates smoothly. Therefore, even when the lower washer seating surface 132 is inclined due to variations in machining and assembly accuracy, it is possible to stably achieve low noise, high efficiency and high reliability.

  Further, even when an impact load is applied to the ball 135 during transportation or the like, the ball 135, the upper washer 31 and the lower washer 139 are relaxed by slightly moving up and down the surface of the lower washer 139 that is elastically supported. Damage to the washer 32 such as dents is less likely to occur, and low noise, high efficiency, and high reliability can be achieved.

  Further, the upper washer 138 and the lower washer 139 can be the same flat plate as in the prior art, and only the elastic member 145 needs to be added, so that manufacturing and assembly can be facilitated.

  Furthermore, since the elastic member 145 is formed of a heat-resistant polymer material, the elastic member 145 is not deteriorated even under high temperature conditions, and can be stably reduced in noise, high efficiency and high reliability. Can do.

  Moreover, since the viscosity of the lubricating oil 106 is VG5 and low viscosity, the loss in a sliding part can be reduced and it can be made still more efficient.

  In this embodiment, the elastic member 145 is made of PA66 material. However, for example, the same effect can be obtained by using the same material such as nylon PA46 (46 nylon) or heat resistant rubber. .

  In this embodiment, the elastic member 145 is used as a means for elastically supporting the surface of the lower washer 139 that contacts the ball 135. However, the upper washer 138 or the lower washer 139 is not used without using the elastic member 145. The same effect can be obtained even if the shape is not a flat plate but a shape having elasticity in the vertical direction, for example, a shape having a U-shaped cross section.

  As described above, the hermetic compressor according to the present invention is less affected by a single piece of the ball, so that low noise, high efficiency, and high reliability are possible. Therefore, the hermetic compressor of the air conditioner or the freezer / refrigerator is used. It can also be applied to applications.

1 is a longitudinal sectional view of a hermetic compressor according to Embodiment 1 of the present invention. Sectional drawing of the principal part of the hermetic compressor in the same embodiment The principal part disassembled perspective view of the hermetic compressor in the same embodiment Vertical section of a conventional hermetic compressor Main part exploded perspective view of a conventional hermetic compressor

Explanation of symbols

DESCRIPTION OF SYMBOLS 101 Airtight container 104 Electric element 105 Compression element 106 Lubricating oil 110 Shaft 111 Main shaft part 112 Eccentric shaft part 114 Cylinder block 116 Compression chamber 120 Main bearing 126 Piston 127 Connection means 131 Upper washer seating surface 132 Lower washer seating surface 135 Ball 138 Upper washer 139 Lower washer 140 Thrust ball bearing 145 Elastic member

Claims (5)

  Lubricating oil is stored in a sealed container, and an electric element and a compression element driven by the electric element are accommodated. The compression element includes a shaft having an eccentric shaft portion and a main shaft portion, and a substantially cylindrical compression chamber. A cylinder block provided; a piston that reciprocates in the compression chamber; a connecting means that connects the piston and the eccentric shaft portion; and a main bearing that is formed in the cylinder block and supports the main shaft portion of the shaft. An upper washer seating surface provided on the shaft and substantially perpendicular to the axis of the main shaft portion; and a lower washer seating surface provided on the main bearing and substantially perpendicular to the shaft center of the main bearing; A thrust ball bearing provided between the upper washer seating surface and the lower washer seating surface, wherein the thrust ball bearing is a holder portion for holding a plurality of balls and the balls; Includes a washer and a lower washer on which are respectively disposed above and below the ball, hermetic compressor, at least one of the upper washer or the lower washer is elastically supported.   The hermetic compressor according to claim 1, wherein an elastic member is interposed between at least one of the upper washer seating surface and the upper washer or between the lower washer seating surface and the lower washer.   3. The hermetic compressor according to claim 1, wherein the hermetic compressor is elastically supported at a position excluding a track of a ball on a surface of the upper washer or the lower washer that does not contact the ball.   The hermetic compressor according to claim 2, wherein the elastic member is formed of a heat-resistant polymer material.   The hermetic compressor according to any one of claims 1 to 4, wherein the lubricating oil has a viscosity of VG3 to VG8.

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