JP2015007409A - Hermetic type compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hermetic type compressor which may supply a lubrication oil to a main shaft part immediately after activation and achieves high reliability.SOLUTION: An oil supply mechanism is provided at a shaft 119 for driving a compression element 107, and the oil supply mechanism includes: a centrifugal pump 135 which is disposed in the shaft and has a lower end opening to a lubrication oil; and a spiral groove 137 provided at an outer periphery of a main shaft part 115. An oil accumulation hole 139 is provided at the main shaft part 115. In the structure, the lubrication oil is accumulated in the oil accumulation hole 139 while the operation is stopped and the lubrication oil accumulated in the oil accumulation hole 139 is discharged by a centrifugal force generated in conjunction with rotations of the shaft 119 during the activation to lubricate a slide part of the main shaft part 115 immediately after the activation. Thus, the occurence of wear and scratches of the slide part of the main shaft part 115 is inhibited to improve the reliability of a hermetic type compressor.

Description

  The present invention relates to an oil supply mechanism for a hermetic compressor.

  In recent years, high reliability is required for hermetic compressors used in refrigeration cycle apparatuses such as household refrigerator-freezers, vending machines, and air conditioners.

  One of the factors to ensure this high reliability is to ensure the lubrication of the sliding part. In a conventional hermetic compressor, an oiling mechanism is provided in the shaft to lubricate the sliding part. Certainty is achieved (for example, refer to Patent Document 1).

  A conventional hermetic compressor will be described below with reference to the drawings.

  FIG. 3 is a longitudinal sectional view of a conventional hermetic compressor, and FIG. 4 is an enlarged view of a main part of the conventional hermetic compressor.

  In the sealed container 1, the lubricating oil 2 is stored, and an electric element 3 and a compression element 4 driven by the electric element 3 are accommodated. The electric element 3 and the compression element 4 are assembled together and elastically supported in the sealed container 1 by a plurality of support springs 5.

  The electric element 3 includes a stator 6 in which plate-shaped stator iron cores are stacked and a copper wire is wound, and a rotor 7 that is rotatably accommodated in the stator 6.

  The compression element 4 has a main shaft portion 8 on which a rotor 7 is mounted and an eccentric shaft portion 9 which is disposed on the upper portion of the main shaft portion 8 and has a shifted center axis, and is used to pump up the lubricating oil 2 upward. A shaft 10 having a mechanism is provided.

  A centrifugal pump 15 that supplies the lubricating oil 2 to each sliding portion such as the compression element 4 and the bearing portion 13 is provided inside the main shaft portion 8 that forms a part of the shaft 10. One end of the centrifugal pump 15 opens into the lubricating oil 2, and the other end communicates with a connection portion 17 with a spiral groove 16 formed on the outer periphery of the main shaft portion 8.

  Further, the compression element 4 includes a cylinder block 12 having a cylindrical compression chamber 11 and a bearing portion 13 that is formed in the cylinder block 12 and rotatably supports the shaft 10.

  A compression chamber 11 formed in the cylinder block 12 is provided with a reciprocating piston 14, and the piston 14 is rotatably connected to an eccentric shaft portion 9 disposed on an upper portion of the shaft 10.

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

  When the electric element 3 is energized, the electric element 3 is activated to rotate the rotor 7, and the shaft 10 mounted integrally with the rotor 7 is rotated, and the eccentricity disposed on the upper part of the shaft 10. The rotational movement of the shaft portion 9 causes the piston 14 that is rotatably connected to reciprocate in the compression chamber 11 to compress the refrigerant.

  The lubricating oil 2 stored in the sealed container 1 is pumped upward by a centrifugal pump 15 provided inside the main shaft portion 8 by centrifugal force generated by the rotation of the shaft 10 as indicated by the dotted arrow in FIG. Then, it passes through the spiral groove 16 formed on the outer periphery of the main shaft portion 8 and is supplied to the sliding portions of the bearing portion 13 and the compression element 4.

  On the other hand, when the energization of the electric element 3 is interrupted, the rotation of the rotor 7 is stopped, and at the same time, the rotation of the shaft 10 mounted integrally with the rotor 7 is also stopped. At this time, the lubricating oil 2 accumulated in the oil supply path of the shaft 10 flows through the oil supply path in the opposite direction to that during operation as indicated by the solid line arrow in FIG. 1 is stored in the lower part.

JP 2000-205129 A

  However, according to the hermetic compressor of Patent Document 1, each sliding part is reliably lubricated during operation, and its reliability is high. However, there is a possibility of insufficient lubrication at the time of start-up and lowering reliability. was there. In other words, in the configuration as in Patent Document 1, the helical groove 16 provided in the sliding portion of the main shaft portion 8 and the lubricating oil 2 staying in the centrifugal pump 15 flow out to the lower part in the sealed container 1 when stopped. Therefore, the amount of the lubricating oil 2 in the sliding portion of the main shaft portion 8 may be extremely reduced.

  Therefore, there is a possibility that the lubricating oil 2 is not sufficiently supplied to the main shaft portion 8 for about 1 to 2 seconds from the start. When starting is performed in such a state and a pressure difference is generated between the high pressure side and the low pressure side, the state in which the lubricating oil 2 is not sufficiently supplied to the main shaft portion 8 to which a high load is applied immediately after the start is 1 Continued for about 2 seconds, the sliding part of the main shaft part 8 rotates with a high load in a state where the lubricating oil 2 is insufficient, which may cause wear and scratches, resulting in a decrease in reliability. .

  SUMMARY OF THE INVENTION The present invention solves the above-described conventional problems, and aims to increase the reliability of a hermetic compressor by allowing lubricating oil to be supplied to a main shaft portion immediately after startup.

  In order to solve the above-mentioned conventional problems, a hermetic compressor according to the present invention stores lubricating oil in a hermetic container, accommodates an electric element and a compression element driven by the electric element, and the compression element Is a cylinder having a compression chamber having a shaft that is rotationally driven by the electric element, has an eccentric shaft portion and a main shaft portion, and has an oil supply mechanism that pumps the lubricating oil upward, and a piston that reciprocates by the shaft. A block, and a bearing portion that is formed on the cylinder block and supports the shaft. The oil supply mechanism is disposed on the shaft, and a centrifugal pump having a lower end opened to the lubricating oil, and a main shaft portion. A spiral groove which is engraved on the outer periphery, one end communicates with the upper part of the centrifugal pump, and the other end communicates with the upper part of the shaft. It is obtained by a configuration in which the fit hole.

  As a result, when the operation is stopped, the lubricating oil is accumulated in the oil reservoir hole, and at the time of start-up, the lubricating oil accumulated in the oil reservoir hole is discharged by the centrifugal force accompanying the rotation of the shaft, thereby lubricating the sliding portion of the main shaft portion. Is performed immediately after starting, and wear and scratches on the sliding portion of the main shaft portion can be suppressed.

The hermetic compressor of the present invention lubricates the sliding portion of the main shaft portion immediately after start-up and suppresses wear and scratches on the sliding portion of the main shaft portion, thus providing a highly reliable hermetic compressor can do.

1 is a longitudinal sectional view of a hermetic compressor according to Embodiment 1 of the present invention. The principal part enlarged view of the shaft and bearing part of the hermetic compressor in Embodiment 1 of the present invention. Vertical section of a conventional hermetic compressor Enlarged view of the main parts 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 and a compression element driven by the electric element are accommodated. The compression element is rotationally driven by the electric element, and an eccentric shaft portion And a main shaft portion, and a shaft having an oil supply mechanism for pumping up the lubricating oil upward, a cylinder block having a compression chamber having a piston reciprocating by the shaft, and a shaft formed on the cylinder block. The oil supply mechanism is disposed on the shaft, the lower end of the centrifugal pump is opened to the lubricating oil, and the main shaft is engraved on the outer periphery, and one end is an upper portion of the centrifugal pump. And a spiral groove with the other end communicating with the upper portion of the shaft, and the main shaft portion is provided with an oil reservoir hole.

  As a result, when the operation is stopped, the lubricating oil is accumulated in the oil reservoir hole, and at the time of start-up, the lubricating oil accumulated in the oil reservoir hole is discharged by the centrifugal force accompanying the rotation of the shaft, thereby lubricating the sliding portion of the main shaft portion. Is performed immediately after starting, and the reliability of the hermetic compressor can be improved by suppressing the wear and scratches on the sliding portion of the main shaft portion.

  In a second aspect based on the first aspect, the oil reservoir hole is provided on a spiral groove on the outer periphery of the main shaft portion.

  As a result, since the spiral groove is a non-sliding portion, an oil reservoir hole is provided in the spiral groove that is a non-sliding portion, thereby preventing a decrease in sliding area and eliminating a decrease in surface pressure of the sliding portion. In addition to the first invention, the reliability can be further improved.

  According to a third invention, in the first or second invention, a plurality of the oil reservoir holes are provided.

  As a result, a larger amount of lubricating oil can be stored in the oil reservoir hole during stoppage, and more lubricating oil can be supplied to the sliding portion of the main shaft portion. In addition to the effects of the first or second invention, In addition, reliability can be improved.

  According to a fourth invention, in the first to third inventions, the oil reservoir hole is inclined by approximately 45 °.

  As a result, by setting the angle of the oil reservoir hole to approximately 45 °, it becomes easier to store the lubricating oil in the oil reservoir hole during stoppage, and at the time of start-up, the centrifugal force accompanying the rotation of the shaft is efficiently used. Thus, since the lubricating oil can be supplied to the sliding portion of the main shaft portion, in addition to the first to third inventions, the reliability can be further improved.

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

(Embodiment)
FIG. 1 is a longitudinal sectional view of a hermetic compressor according to Embodiment 1 of the present invention, and FIG. 2 is an enlarged view of a main part of a shaft and a bearing portion of the hermetic compressor according to Embodiment 1 of the present invention.

  In FIG. 1 and FIG. 2, lubricating oil 103 is stored in an airtight container 101, and an electric element 105 and a compression element 107 driven by the electric element 105 are accommodated, respectively. 107 is integrally assembled and elastically supported in the sealed container 101 by a plurality of support springs 109.

  The electric element 105 includes a stator 111 in which plate-shaped stator iron cores are stacked and a copper wire is wound, and a rotor 113 that is rotatably accommodated in the stator 111.

  The compression element 107 includes a main shaft portion 115 on which a rotor 113 is mounted, an eccentric shaft portion 117 disposed on the upper portion of the main shaft portion 115 and shifted from the center axis, and an oil supply mechanism that pumps up the lubricating oil 103 upward. A shaft 119 provided, a cylinder block 123 provided with a cylindrical compression chamber 121, a suction muffler 125 for introducing a refrigerant (not shown) in the sealed container 101 into the cylindrical compression chamber 121, and a cylinder block 123 A bearing portion 127 that is formed and rotatably supports the shaft 119.

  A cylindrical compression chamber 121 formed in the cylinder block 123 is provided with a piston 129 that reciprocates. The piston 129 is connected to an eccentric shaft portion 117 disposed on an upper portion of the shaft 119 via a connecting rod 131. It is connected rotatably. Further, the main shaft portion 115 of the shaft 119 is provided with a hollow portion 133 that is formed by being sandwiched in the axial direction by a sliding portion with the bearing portion 127, reduces the outer diameter, and is a non-sliding portion.

  Further, a centrifugal pump 135 for supplying the lubricating oil 103 to each sliding portion such as the compression element 107, the bearing portion 127, and the main shaft portion 115 is provided below the shaft 119 inside the shaft 119. . One end of the centrifugal pump 135 opens into the lubricating oil 103 and the other end communicates with a spiral groove 137 carved on the outer periphery of the main shaft 115. Further, the main shaft portion 115 is provided with a plurality of oil reservoir holes 139 whose one ends are closed in a spiral groove 137 serving as an oil supply passage. The connecting portion 141 in which one end of the centrifugal pump 135 and one end of the spiral groove 137 communicate with each other faces a sliding portion with the bearing portion 127.

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

  When the electric element 105 is energized, the electric element 105 is activated and the rotor 113 rotates. The shaft 119 rotates integrally with the rotor 113, and the rotational movement of the eccentric shaft portion 117 causes the piston 129 to reciprocate in the compression chamber 121 via the connecting rod 131.

  A refrigerant (not shown) in the sealed container 101 is sucked into the compression chamber 121 through the suction muffler 125, and suction and compression operations are performed by the reciprocating motion of the piston 129 in the compression chamber 121.

  In such a hermetic compressor, the return path of the lubricating oil 103 when stopped will be described next.

When the power supply to the electric element 105 is cut off, the rotation of the shaft 119 mounted on the rotor 113 is stopped, and the outer diameter is reduced from the spiral groove 137 and the main shaft portion 115 formed on the outer periphery of the main shaft portion 115. Further, the lubricating oil 103 remaining in the space between the hollow portion 133 and the bearing portion 127 is caused to move down the spiral groove 137 in the opposite direction to the oil supply path as indicated by the arrow (solid line) in FIG. 2 due to its own weight. A part of the flow is stored in an oil reservoir hole 139 provided in the main shaft portion 115, and the remaining lubricating oil 103 passes through a connecting portion 141 between the spiral groove 137 and the centrifugal pump 135, and the outer peripheral side wall surface of the centrifugal pump 135. It passes through and returns to the lubricating oil 103 at the bottom of the sealed container 101.

  Next, the oil supply path at the time of starting will be described.

  When the shaft 119 rotates, the lubricating oil 103 flows into the centrifugal pump 135 provided below the shaft 119 immersed in the lubricating oil 103 stored in the lower part of the sealed container 101, and due to the centrifugal force accompanying the rotation, As shown by the arrow (dotted line) in FIG. 2, along the inclination direction of the centrifugal pump 135 part, the pump is pumped upward along the outer peripheral side wall surface, To the connecting portion 141.

  The lubricating oil 103 reaching the connecting portion 141 between one end of the centrifugal pump 135 and the lower end portion of the spiral groove 137 is pumped further upward while lubricating the main shaft portion 115 and the bearing portion 127, and the connecting rod 131, piston 129, etc. The remaining portion is supplied to the sliding portion, and the rest is discharged from the upper end of the eccentric shaft portion 117 into the space in the sealed container 101. Therefore, it takes about 1 to 2 seconds after the start-up until the lubricating oil 103 stored in the lower part of the sealed container 101 is sufficiently conveyed to the main shaft 115.

  On the other hand, the lubricating oil 103 stored in the oil reservoir hole 139 provided in the main shaft portion 115 is immediately discharged by the centrifugal force due to the rotation of the shaft 119 immediately after activation, and is discharged to the main shaft portion 115 for about 1 to 2 seconds. Without this, the main shaft 115 is lubricated immediately after startup.

  That is, not only during normal startup in which the pressure on the high-pressure side and the pressure on the low-pressure side are balanced, but also in the state where there is a pressure difference between the pressure on the high-pressure side and the pressure on the low-pressure side. Even if it is applied, the lubricating oil 103 stored in the oil reservoir hole 139 disposed in the vicinity of the main shaft portion 115 is supplied from immediately after the start without elapse of about 1 to 2 seconds. Will be done.

  Therefore, even if it is started in a harsh state such as when a pressure difference is generated between the high pressure side and the low pressure side, it can prevent lubrication hindrance and suppress the occurrence of wear and scratches on the main shaft 115, Reliability can be improved.

  Further, in this embodiment, the oil reservoir hole 139 is provided on the spiral groove 137 formed on the outer periphery of the main shaft portion 115, so that the surface pressure of the sliding portion does not decrease and the reliability is further improved. can do. That is, since the spiral groove 137 portion is originally a non-sliding portion, by providing the oil reservoir hole 139 in the spiral groove 137 portion which is a non-sliding portion, it is possible to prevent the sliding area from being lowered. As a result, there is no decrease in the surface pressure of the sliding portion, and the reliability can be further improved.

  Further, since a plurality of oil reservoir holes 139 are provided, a larger amount of the lubricating oil 103 can be stored in the oil reservoir hole 139 during the stop, and at the time of start-up, the shaft 119 is rotated. Since more lubricating oil 103 stored in the plurality of oil reservoir holes 139 can be supplied to the main shaft 115 immediately after startup by the centrifugal force, the reliability can be further improved.

Further, the oil reservoir hole 139 may be provided with an inclination of approximately 45 ° with respect to the vertical direction of the shaft 119, so that the lubricating oil 103 is stored in the oil reservoir hole 139 while stopping, At the time of start-up, the centrifugal oil accompanying the rotation of the shaft 119 can be efficiently used to supply the lubricating oil, so that the main shaft 115 can be more efficiently lubricated and the reliability can be further improved. it can.

  As described above, the hermetic compressor according to the present invention lubricates the sliding portion of the main shaft portion immediately after starting to suppress wear and scratches on the sliding portion of the main shaft portion. The compressor can be a type compressor, and is widely applicable not only to household electric refrigerators but also to air conditioners, vending machines, and other refrigeration apparatuses.

DESCRIPTION OF SYMBOLS 101 Airtight container 103 Lubricating oil 105 Electric element 107 Compression element 111 Stator 113 Rotor 115 Main shaft part 117 Eccentric shaft part 119 Shaft 121 Compression chamber 123 Cylinder block 127 Bearing part 135 Centrifugal pump 137 Spiral groove 139 Oil reservoir hole

Claims (4)

The lubricating oil is stored in an airtight container, and an electric element and a compression element driven by the electric element are accommodated. The compression element is rotationally driven by the electric element and has an eccentric shaft portion and a main shaft portion. And a shaft provided with an oil supply mechanism for pumping the lubricating oil upward, a cylinder block having a compression chamber having a piston reciprocatingly moved by the shaft, and a bearing portion that is formed in the cylinder block and supports the shaft. The oil supply mechanism is disposed on the shaft, the lower end of the centrifugal pump is opened to the lubricating oil, the outer periphery of the main shaft portion is engraved, one end communicates with the upper portion of the centrifugal pump, the other end And a spiral groove communicating with an upper portion of the shaft, and a hermetic compressor provided with an oil reservoir hole in the main shaft portion. The hermetic compressor according to claim 1, wherein the oil reservoir hole is provided on a spiral groove on an outer periphery of the main shaft portion. The hermetic compressor according to claim 1, wherein a plurality of the oil reservoir holes are provided. The hermetic compressor according to any one of claims 1 to 3, wherein the oil reservoir hole is inclined at approximately 45 °.