JP2010112174A - Rotary compressor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rotary compressor for reducing an input loss, by reducing a sliding loss in an upper bearing, by improving slidability of a rotating shaft and an inner peripheral sliding surface of the upper bearing. <P>SOLUTION: An oil groove 15 arranged on the inner peripheral sliding surface of the upper bearing 6 has a first oil groove 15A and a second oil groove 15B divided in the axial direction of a shaft 4 by the cylinder 5 side and the compression driving part (electric motor part 102) side. Since the first oil groove 15A and the second oil groove 15B can improve the slidability of the rotating shaft 4 and the inner peripheral sliding surface of the upper bearing 6 by minimizing reduction in load capacity by the oil groove of the upper bearing 6 by arranging an angle difference of about 180° in the circumferential direction of the inner peripheral sliding surface of the upper bearing 6, the sliding loss in the upper bearing can be reduced. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a rotary compressor incorporated in a room air conditioner, a refrigerator, and an air conditioner.

  In a conventional rotary compressor, an electric motor part of a compression driving part and a compression mechanism part driven by the electric motor part are housed in a hermetic container, and the bottom part of the hermetic container serves as an oil reservoir. The electric motor part is composed of a stator and a rotor, and the rotation of the rotor is transmitted to the compression mechanism part via the shaft. The compression mechanism has a cylinder, an upper bearing fastened to the end surface of the cylinder on the electric motor side, and a lower bearing fastened to the opposite end surface, and a shaft positioned between the upper bearing and the lower bearing. A piston is fitted to the eccentric portion of the, and a suction chamber and a compression chamber partitioned in the cylinder are formed by a vane contacting the piston. The volume of the suction chamber and the compression chamber changes due to the eccentric rotation of the piston and the reciprocating movement of the vane, and this change in volume compresses the refrigerant gas sucked from the suction port of the compression mechanism into the suction chamber in the cylinder. The refrigerant gas is discharged from the compression chamber in the cylinder through the discharge port and the discharge muffler chamber into the sealed container. Then, after the refrigerant gas discharged from the rotary compressor is radiated by the radiator in the refrigeration cycle, the refrigerant is squeezed by the expansion valve, absorbed by the evaporator, and again sucked into the rotary compressor.

  Also, the oil in the oil reservoir is sucked by the oil pump provided at the end of the shaft opposite to the motor part, and the oil passes through the shaft, and the inner sliding surface of the upper bearing and the inner sliding surface of the lower bearing. Oil is supplied to the moving surface to lubricate the sliding portion (see, for example, Patent Document 1).

  6 and 7 show a conventional rotary compressor described in Patent Document 1. FIG. As shown in FIGS. 6 and 7, a force F1 generated by the differential pressure between the compression chamber side pressure Pc and the suction chamber side pressure Ps in the cylinder 35 is applied to the shaft 44 via the piston 38 from the compression chamber 34 to the suction chamber. It acts in the direction of 33 and is supported by an upper bearing 36 and a lower bearing 37 fastened to both end faces of the cylinder 35. In particular, when the position of the shaft 44 at the time when the vane 39 protrudes most inside the cylinder 35 is 0 °, the position of the shaft 44 is at an angle of approximately 90 ° or more and less than 180 °, and the compression chamber side in the cylinder 35. The differential pressure between the pressure Pc and the suction chamber side pressure Ps is the highest. On the inner peripheral sliding surfaces of the upper bearing 36 and the lower bearing 37, the position of the vane groove 30 when the upper bearing 36 and the lower bearing 37 are viewed from the electric motor side. Is set to 0 °, the highest force acts at an angle of approximately 90 ° to less than 180 ° in the direction in which the shaft 44 rotates.

Conventionally, on the inner peripheral sliding surfaces of the upper bearing 36 and the lower bearing 37, one oil groove is provided for the purpose of oil supply and cooling for forming a lubricating oil film of the bearing portion. The circumferential position of both the upper and lower bearings is an angle of approximately 270 ° to less than 360 ° in the direction in which the shaft 44 rotates, that is, the pressure generated by the lubricating oil film in the oil groove is zero. Thus, a position where a large load capacity of the bearing can be secured with respect to the direction of the force generated by the differential pressure has been selected. As a result, a suitable lubricating oil film is formed on the bearing portion to improve the slidability between the rotating shaft and the inner peripheral sliding surfaces of the upper bearing and the lower bearing, thereby reducing input.
JP 2003-214369 A

However, in the conventional configuration, as shown in FIG. 7, the upper bearing 36 is increased in length in the axial direction of the shaft 44 in order to keep the surface pressure of the bearing portion small. A force generated by a differential pressure between the compression chamber side pressure Pc and the suction chamber side pressure Ps in the cylinder 35 acts on the moving surface in the direction from the compression chamber to the suction chamber, and the motor portion side of the upper bearing 36, that is, compression drive. A force approximately 180 ° opposite to the cylinder side and circumferential direction acts on the inner circumferential sliding surface on the part side. Therefore, the angle at which the force generated by the differential pressure is the highest is such that when the upper bearing 36 is viewed from the compression drive unit side and the position of the vane groove 30 is 0 °, the inner side sliding of the upper bearing 36 on the cylinder side. The moving surface has an angle of about 90 ° to less than 180 ° in the direction in which the shaft 44 rotates, and the compression driving portion side inner peripheral sliding surface has an angle in the direction of rotation of the shaft 44 to about 270 ° to less than 360 °. Since the oil groove provided on the inner peripheral sliding surface of the bearing is present in the vicinity of the circumferential direction, the load capacity of the upper bearing is significantly reduced, the sliding loss is increased, and the input loss is generated.

  The present invention solves the above-mentioned conventional problems, and on the compression drive part side of the upper bearing, suppresses a decrease in load capacity due to the oil groove of the upper bearing, and the rotating shaft and the inner peripheral sliding surface of the upper bearing An object of the present invention is to provide a rotary compressor in which the slidability is improved and the input loss is small.

  In order to solve the above-described conventional problems, the rotary compressor of the present invention includes a first oil groove that is divided in the axial direction of the shaft on the cylinder side and the compression drive unit side on the inner peripheral sliding surface of the upper bearing. A second oil groove is provided, and the first oil groove and the second oil groove are provided with an angular difference of about 180 ° in the circumferential direction of the inner peripheral sliding surface of the upper bearing. As a result, when there is an angular difference of approximately 180 ° in the circumferential direction between the inner bearing sliding surface on the cylinder side of the upper bearing and the sliding surface on the compression drive unit in the direction of the force generated by the differential pressure, The oil groove provided on the inner peripheral sliding surface of the upper bearing can be avoided from the vicinity of the circumferential direction of the angle that most acts on the cylinder inner peripheral sliding surface and the compression drive side sliding surface of the upper bearing. .

  The rotary compressor of the present invention can suppress a decrease in load capacity due to the oil groove of the upper bearing, and can improve the slidability between the rotating shaft and the inner peripheral sliding surface of the upper bearing. Therefore, it is possible to provide a rotary compressor that reduces the sliding loss of the upper bearing and has a small input loss.

  According to a first aspect of the present invention, a compression mechanism portion and a compression drive portion for driving the compression mechanism portion are accommodated in a sealed container, and the compression mechanism portion is an upper bearing disposed on both ends of the cylinder and the cylinder. And a lower bearing, a piston that rotates in the cylinder, and an oil supply hole that drives the piston and supplies oil from the oil reservoir in the sealed container to the inner peripheral sliding surfaces of the upper bearing and the lower bearing. A rotary compressor having a shaft, a vane that divides the inside of the cylinder into a suction chamber and a compression chamber, and a vane groove that is formed in the cylinder and in which the vane reciprocates, the inner peripheral sliding surface of the upper bearing The first oil groove and the second oil groove are divided in the axial direction of the shaft on the cylinder side and the compression drive part side, and the first oil groove and the second oil groove are the inner circumference of the upper bearing. Approximate in the circumferential direction of the sliding surface By providing an angle difference of 80 °, the inner bearing sliding surface on the cylinder side of the upper bearing and the compression drive unit side in the direction of the force generated by the pressure difference between the compression chamber side pressure Pc and the suction chamber side pressure Ps in the cylinder. When there is an angle difference of approximately 180 ° in the circumferential direction on the sliding surface, the circumferential direction of the angle at which this force is most effective on the inner bearing sliding surface on the cylinder side of the upper bearing and the sliding surface on the compression drive unit The oil groove provided on the inner peripheral sliding surface of the upper bearing can be avoided from the vicinity.

In the second aspect of the invention, particularly in the rotary compressor of the first aspect, when the position of the vane groove is set to 0 ° when the upper bearing is viewed from the compression drive unit side, the shaft is connected to the first oil groove on the cylinder side. Since the second oil groove on the compression drive unit side is provided at an angle of approximately 90 ° to less than 180 ° in the direction of rotation of the shaft at an angle of approximately 270 ° to less than 360 ° in the rotating direction, the cylinder of the upper bearing On the side inner peripheral sliding surface, the force acting at an angle of approximately 90 ° or more and less than 180 ° in the direction in which the shaft rotates, and the upper bearing compression driving portion side inner peripheral sliding surface in the direction in which the shaft rotates. With respect to a force acting on an angle of 270 ° or more and less than 360 °, a decrease in load capacity due to the oil groove of the upper bearing can be suppressed to a minimum.

  According to a third aspect of the invention, in particular, in the rotary compressor of the first aspect, an annular groove larger than the inner diameter of the upper bearing is provided on the inner peripheral sliding surface of the upper bearing, and the first oil on the cylinder side is provided. By configuring the groove to communicate with the second oil groove on the compression drive unit side, oil supplied from the oil supply hole of the shaft to the cylinder-side inner sliding surface of the upper bearing is released to the annular groove, In addition, oil can be supplied from the annular groove to the inner peripheral sliding surface on the compression drive unit side.

  In the fourth aspect of the invention, in particular, the rotary compressor of the first aspect of the present invention is provided with an annular groove smaller than the outer diameter of the shaft on the outer peripheral sliding surface of the shaft facing the upper bearing. By configuring the first oil groove and the second oil groove on the compression drive unit side to communicate with each other, the oil supplied from the oil supply hole of the shaft to the cylinder side inner peripheral sliding surface of the upper bearing is annular. Oil can escape from the groove and can be supplied from the annular groove to the inner peripheral sliding surface of the compression drive unit.

  According to a fifth aspect of the present invention, in particular, in the rotary compressor of the first aspect of the present invention, an oil relief hole extending from the inner surface of the first oil groove on the cylinder side to the outer side of the upper bearing and the shaft is formed. By providing an inner peripheral sliding surface including a groove and an oil supply hole for supplying oil to the inner peripheral sliding surface including a second oil groove on the compression drive unit side, the cylinder of the upper bearing from the oil supply hole The oil supplied to the inner peripheral sliding surface is released to the outer side of the upper bearing through an oil escape hole that extends to the outer side of the upper bearing, and oil is supplied from the oil supply hole to the inner peripheral sliding surface on the compression drive unit side. Can be refueled.

  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 1)
FIG. 1 is a longitudinal sectional view showing a rotary compressor according to a first embodiment of the present invention, FIG. 2 is a sectional view showing an arrow AA in FIG. 1, and FIG. 3 is a first embodiment of the present invention. FIG. 4 is a cross-sectional view taken along line BB in FIG. 1.

  In FIG. 1, reference numeral 100 denotes a rotary compressor that uses R410A as a refrigerant gas. The rotary compressor 100 includes a cylindrical hermetic container 1, an electric motor unit 102 disposed on the upper side of the hermetic container 1, and the electric motor. The compression mechanism unit 101 is arranged below the unit 102 and driven by the electric motor unit 102, and the bottom of the sealed container 1 is used as an oil reservoir.

  The electric motor unit 102 includes a stator 2 that is annularly attached along the inner peripheral surface on the inner upper side of the sealed container 1, and a rotor 3 that is inserted with a slight gap inside the stator 2. The rotor 3 is fixed to the shaft 4 in the vertical direction at the center.

  The compression mechanism unit 101 includes a cylinder 5, an upper bearing 6 fastened to the end surface of the cylinder 5 on the electric motor side, and a lower bearing 7 fastened to the end surface on the opposite side. The upper bearing 6 and the lower bearing 7 supports the shaft 4 in the radial direction. A piston 8 is fitted to an eccentric portion of the shaft 4 located between the upper bearing 6 and the lower bearing 7.

  As shown in FIG. 3, the oil groove 15 provided on the inner peripheral sliding surface of the upper bearing 6 is a first divided in the axial direction of the shaft 4 on the cylinder 5 side and the compression drive part (electric motor part 102) side. Oil groove 15A and second oil groove 15B. The first oil groove 15A and the second oil groove 15B have an angular difference of about 180 ° in the circumferential direction of the inner peripheral sliding surface of the upper bearing 6. It is provided. Specifically, as shown in FIG. 4, when the position of the vane groove is 0 ° when the upper bearing 6 is viewed from the electric motor unit 102 side, the oil groove 15 </ b> A on the cylinder side is approximately in the direction in which the shaft 4 rotates. The oil groove 15B on the motor unit side is provided at an angle of approximately 90 ° to less than 180 ° in the direction in which the shaft 4 rotates at an angle of 270 ° to less than 360 °. Also, an annular groove 15C larger than the inner diameter of the upper bearing 6 is provided on the inner peripheral sliding surface of the upper bearing 6, and the cylinder-side oil groove 15A and the motor section-side oil groove 15B are communicated with each other. .

  As shown in FIG. 2, the cylinder 5 is provided with a vane groove 10 for slidably disposing the vane 9 and a vane spring hole 12 for accommodating a vane spring 11 disposed on the radially outer side of the vane 9. The vane 9 is reciprocated in the vane groove 10 by the eccentric rotation of the shaft 4, and the spring force is urged by the vane spring 11 to come into contact with the outer peripheral surface of the piston 8, and the suction separated by the vane 9 in the cylinder 5. A chamber 13 and a compression chamber 14 are formed.

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

  First, when the electric motor unit 102 is activated, the rotor 3 rotates. With this rotation, the piston 8 fitted to the eccentric portion of the shaft 4 rotates eccentrically along the inner peripheral surface of the cylinder 5 together with the rotation of the shaft 4, and the suction chamber 13 and the compression chamber 14 partitioned by the vanes 9. The volume of changes.

  Thus, the refrigerant gas sucked into the suction chamber 13 in the cylinder 5 from the suction port 17 formed in the cylinder 5 via the suction liner 16 is compressed by the operation of the piston 8 and the vane 9, and the cylinder 5 The air is discharged into the sealed container 1 from the inner compression chamber 14 through the discharge port 18, the upper bearing 6, and the discharge muffler chamber 103 surrounded by the valve cover 19 disposed and fixed above the upper bearing 6.

  At the same time, an oil pump 20 is provided at the end of the shaft 4 opposite to the motor part 102. When the shaft 4 rotates, the oil pump 20 sucks oil in the oil reservoir, and the sucked oil is 4, lubricated to the inner peripheral sliding surface of the upper bearing 6 and the inner peripheral sliding surface of the lower bearing 7 to lubricate the sliding parts, and lubricated to the sliding parts of each part in the cylinder 5 Lubricate the sliding part.

  A force generated by the pressure difference between the compression chamber side pressure Pc and the suction chamber side pressure Ps in the cylinder 5 acts on the inner peripheral sliding surface of the upper bearing 6, and the direction in which this force acts highest is the upper bearing 6. When the position of the vane groove 10 is 0 ° when viewed from the motor unit 102 side, the cylinder side inner peripheral sliding surface of the upper bearing 6 has an angle of approximately 90 ° to less than 180 ° in the direction in which the shaft 4 rotates. In the motor part side inner peripheral sliding surface, the angle is approximately 270 ° or more and less than 360 ° in the direction in which the shaft 4 rotates. Therefore, the oil groove 15A on the cylinder side is approximately 270 ° or more and 360 ° in the direction in which the shaft 4 rotates. By providing the oil groove 15B on the motor section side at an angle of less than 90 ° and less than 180 ° in the direction in which the shaft 4 rotates, the load capacity drop due to the oil groove of the upper bearing 6 is minimized. And rotate Since it is possible to improve the sliding property between the shift 4 and the inner circumferential sliding surface of the upper bearing 6, it is possible to reduce the sliding loss of the upper bearing.

Further, although not shown in the drawings, means for releasing oil supplied to the cylinder side inner peripheral sliding surface of the upper bearing 6 and supplying oil to the motor unit side inner peripheral sliding surface of the first embodiment is not shown. An annular groove smaller than the outer diameter of the shaft is provided on the outer peripheral sliding surface of the shaft facing the upper bearing so that the oil groove on the cylinder side communicates with the oil groove on the compression drive unit side. Thus, the same effect as in the present embodiment can be obtained. Specifically, the oil supplied from the oil supply hole of the shaft to the cylinder side inner peripheral sliding surface of the upper bearing is released to the annular groove, and the annular groove is transferred to the inner peripheral sliding surface of the compression drive unit. Oil can be supplied.

  Further, as shown in FIG. 5, the means for releasing oil supplied to the cylinder-side inner peripheral sliding surface of the upper bearing and supplying oil to the inner peripheral sliding surface on the electric motor unit side of the first embodiment as shown in FIG. Formed in the upper bearing 6 and formed in the shaft 4 and the oil relief hole 21 extending from the inner surface of the cylinder side oil groove 15A provided on the inner peripheral sliding surface of the upper bearing 6 to the outside of the upper bearing 6, By providing the inner peripheral sliding surface including the oil groove 15A and the oil supply hole for supplying oil to the inner peripheral sliding surface including the oil groove 15B on the motor unit side, the same effect as in this embodiment is obtained. It is done. Specifically, the oil supplied from the oil supply hole to the inner bearing sliding surface on the cylinder side of the upper bearing is released to the outside of the upper bearing via the oil escape hole that extends to the outside of the upper bearing. Oil can be supplied to the inner peripheral sliding surface on the compression drive unit side.

As described above, since the rotary compressor according to the present invention can reduce input loss, it can also be applied to CO ₂ compressors for hot water heaters and air compression applications.

The longitudinal cross-sectional view which shows the rotary compressor in the 1st Embodiment of this invention Sectional drawing which shows the AA arrow of FIG. 1 is a longitudinal sectional view of an essential part showing a rotary compressor according to a first embodiment of the present invention. Sectional drawing which shows the BB arrow of FIG. The principal part longitudinal cross-sectional view which shows the rotary compressor in other embodiment of this invention. Main part sectional drawing which shows the conventional rotary compressor Longitudinal cross-sectional view of a main part showing a conventional rotary compressor

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Airtight container 2 Stator 3 Rotor 4 Shaft 5 Cylinder 6 Upper bearing 7 Lower bearing 8 Piston 9 Vane 10 Vane groove 11 Vane spring 12 Vane spring hole 13 Suction chamber 14 Compression chamber 15 Oil groove 15A Cylinder side oil groove 15B Oil on motor side Groove 16 Suction liner 17 Suction port 18 Discharge port 19 Valve cover 20 Oil pump 21 Oil relief hole 22 Oil supply hole 100 Rotary compressor 101 Compression mechanism section 102 Electric motor section 103 Discharge muffler chamber,

Claims (5)

In the sealed container, a compression mechanism part and a compression drive part for driving the compression mechanism part are housed, and the compression mechanism part includes a cylinder, and upper and lower bearings disposed on both end faces of the cylinder. A piston that rotates in the cylinder, and an oil supply hole that drives the piston and supplies oil from the oil reservoir in the sealed container to the inner peripheral sliding surfaces of the upper bearing and the lower bearing. A rotary compressor having a shaft, a vane that divides the inside of the cylinder into a suction chamber and a compression chamber, and a vane groove that is formed in the cylinder and in which the vane reciprocates. A first oil groove and a second oil groove that are divided in the axial direction of the shaft on the cylinder side and the compression drive part side on a circumferential sliding surface, the first oil groove and the second oil groove; Oy Groove, the rotary compressor is characterized by providing an angular difference of approximately 180 ° in the circumferential direction of the inner circumferential sliding surface of the upper bearing. When the position of the vane groove is 0 ° when the upper bearing is viewed from the compression drive side, the first oil groove on the cylinder side is compressed at an angle of about 270 ° to less than 360 ° in the shaft rotation direction. 2. The rotary compressor according to claim 1, wherein a second oil groove on a part side is provided at an angle of approximately 90 ° to less than 180 ° in a direction in which the shaft rotates. An annular groove larger than the inner diameter of the upper bearing is provided on the inner peripheral sliding surface of the upper bearing so that the first oil groove on the cylinder side communicates with the second oil groove on the compression drive unit side. The rotary compressor of Claim 1 comprised in this. An annular groove smaller than the outer diameter of the shaft is provided on the outer peripheral sliding surface facing the upper bearing of the shaft, and a first oil groove on the cylinder side and a second oil groove on the compression drive unit side are provided. The rotary compressor of Claim 1 comprised so that it might communicate. An oil escape hole formed on the upper bearing and extending from the inner surface of the first oil groove on the cylinder side to the outer side of the upper bearing; an inner peripheral sliding surface formed on the shaft and including the first oil groove on the cylinder side; 2. The rotary compressor according to claim 1, further comprising an oil supply hole that supplies oil to an inner peripheral sliding surface including a second oil groove on the compression drive unit side.