System for transporting lubricating oil in a compressor

Abstract

The present invention relates to a lubricating oil transport system in a compressor, in which: the rotating shaft ( 3 ) has at least one concavity ( 35 ) that extends over part of the rotating surface ( 33 ) in contact with the internal surface ( 11 ) of the rotor ( 1 ) and at least one restrictor hole ( 34 ) that communicates with the internal region of the rotating shaft ( 3 ) and with the concavity ( 35 ); the rotor ( 1 ) comprises a circumferential channel ( 12 ) and at least one radial channel ( 13 ) extending through the inner wall ( 11 ) of the rotor ( 1 ); the radial channel ( 13 ) is arranged around the circumferential channel ( 12 ); said circumferential channel ( 12 ) and the radial channel ( 13 ) communicating with the concavity ( 35 ); the circumferential channel ( 12 ), the radial channel ( 13 ) and the concavity ( 35 ) transport oil for cooling the upper part of the rotor ( 1 ) and the stator ( 2 ).

1 . System for transporting lubricating oil in a compressor, comprising:
 a housing;   an electric motor comprising a rotor and a stator,   the rotor comprising at least one inner wall;   an oil pump and an oil reservoir arranged inside the housing;   a rotating shaft as an integral part of the electric motor;   a compressor block configured to house, at least partially, the rotating shaft;   the rotating shaft supported by at least one radial bearing;   the rotating shaft comprising a lower region, an upper region and a rotating surface;   wherein the rotating shaft has at least one concavity that extends over part of the rotating surface in contact with the internal surface of the rotor and at least one restrictor hole which communicates with the internal region of the rotating shaft and with the concavity;   the rotor comprises a circumferential channel and at least one radial channel extending through the inner wall of the rotor;   the radial channel is arranged around the circumferential channel;   the circumferential channel and the radial channel communicating with the concavity;   the circumferential channel, the radial channel and the concavity configured to transport oil for cooling the upper part of the rotor and the stator.   
     
     
         2 . System for transporting lubricating oil in a compressor, according to  claim 1 , wherein the concavity has a helicoid shape. 
     
     
         3 . System for transporting lubricating oil in a compressor, according to  claim 1 , wherein the circumferential channel has an external diameter smaller than the external diameter of the rotating shaft housing in the compressor block. 
     
     
         4 . System for transporting lubricating oil in a compressor, according to  claim 1 , wherein the radial channel outlet is inscribed in a circle with a diameter larger than the outer diameter of the rotating shaft housing in the compressor block. 
     
     
         5 . System for transporting lubricating oil in a compressor, comprising:
 a housing;   an electric motor comprising a rotor and a stator,   the rotor comprising at least one inner wall;   an oil pump and an oil reservoir arranged inside the housing;   a rotating shaft as an integral part of the electric motor;   a compressor block capable of housing, at least partially, the rotating shaft;   the rotating shaft supported by at least one radial bearing;   the rotating shaft comprising a lower region, an upper region and a rotating surface;   wherein the rotor has at least one radial channel arranged around a circumferential channel;   wherein the circumferential channel extends over at least part of the inner wall of the rotor;   wherein the circumferential channel is located at an intermediate level between the upper part of the oil pump and the lower region of the rotating shaft;   wherein the circumferential channel and the radial channel carry oil for cooling the upper part of the rotor and the stator; and   wherein there is a partial juxtaposition between the entrance of the radial channel and the outer diameter of the circumferential channel.   
     
     
         6 . The system according to  claim 1 or claim 5 , wherein the rotor is configured for an asynchronous induction motor, and wherein the radial channels and circumferential channel are formed by stacking a plurality of magnetic steel laminations, each lamination being rotated by a composite angle β relative to the preceding lamination, wherein the composite angle β comprises a lamination skew angle Δα, based on a skew angle α defined by the greater of the stator slot pitch and rotor slot pitch, and an interlock angle φ, defined by the number and arrangement of rotor bars, and wherein the number of radial channels nr is selected as an integer near to 360 divided by β. 
     
     
         7 . The system according to  claim 6 , wherein each lamination includes circular cutouts equally spaced around the circumferential channel, the circular cutouts configured such that, when the laminations are stacked and angularly aligned, the circular cutouts form continuous radial channels extending radially outward from the circumferential channel toward the rotor periphery. 
     
     
         8 . The system according to  claim 6 or claim 7 , wherein the stacking orientation of each lamination is always performed by rotating each lamination in the same angular direction as the skewed rotor bar slots, and the result arrangement will differ depending on the relationship between θ and β:
 if θ>β, the radial channel pitch visually appears to follow the same angular direction as the skewed rotor bar slots; and 
 If θ<β, although each lamination is still rotated in the same direction, the radial channel pitch visually appear stacked in the opposite angular direction relative to the skewed rotor bar slots. 
 
     
     
         9 . The system according to  claim 8 , wherein the radial channel pitch is selected so the radial channels appear oriented opposite the rotor rotation direction, and wherein the radial channel pitch direction matches the pitch direction of the shaft concavity.