Motor operated compressor

Abstract

A motor operated compressor according to the present invention has a driving motor having a stator and a rotor. A rotation shaft of the motor is coupled to the rotor. The compressor also has a frame, a fixed scroll positioned on one side of the frame, and an orbiting scroll supported on the frame and positioned between the fixed scroll and the frame. The fixed scroll forms a compression chamber together with the orbiting scroll. The driving motor, the fixed scroll, the orbiting scroll, and the frame are positioned within a casing of the compressor. The rotation shaft rotatably passes through the fixed scroll and the frame and is to eccentrically coupled to the orbiting scroll, allowing the orbiting scroll to perform an orbiting motion relative to the fixed scroll. One end portion of the rotation shaft is supported by the fixed scroll while the other end is supported by the casing.

What is claimed is: 
     
         1 . A motor operated compressor, comprising:
 a driving motor having a rotation shaft;   a frame provided on one side of the driving motor in an axial direction;   an orbiting scroll supported on the frame in the axial direction and eccentrically coupled to the rotation shaft to perform an orbiting motion;   a fixed scroll provided at an opposite side of the frame with the orbiting scroll interposed therebetween, the fixed scroll forming a compression chamber together with the orbiting scroll and supporting one end portion of the rotation shaft in a radial direction, wherein the rotation shaft passes through the frame and the orbiting scroll; and   a casing provided at an opposite side of the frame with the driving motor interposed therebetween, the casing supporting another end portion of the rotation shaft in the radial direction.   
     
     
         2 . The compressor of  claim 1 , wherein the fixed scroll includes a first shaft supporting portion protruding therefrom, the one end portion of the rotation shaft being rotatably inserted in the first shaft supporting portion, and
 wherein the first shaft supporting portion includes a first bearing disposed on an inner circumferential surface of the first shaft supporting portion to support the one end portion of the rotation shaft.   
     
     
         3 . The compressor of  claim 2 , wherein the casing includes a second shaft supporting portion protruding therefrom in a direction toward the driving motor, the another end portion of the rotation shaft being rotatably inserted in the second shaft supporting portion, and
 wherein the second shaft supporting portion includes a second bearing disposed on an inner circumferential surface of the second shaft supporting portion to support the another end portion of the rotation shaft.   
     
     
         4 . The compressor of  claim 3 , wherein the frame includes a frame shaft hole through which the rotation shaft is inserted, and
 wherein a gap between an inner circumferential surface of the frame shaft hole and an outer circumferential surface of the rotation shaft is larger than one of a gap between an inner circumferential surface of the first bearing and the outer circumferential surface of the rotation shaft, or a gap between an inner circumferential surface of the second bearing and the outer circumferential surface of the rotation shaft.   
     
     
         5 . The compressor of  claim 4 , wherein the frame includes a first space portion formed on one side surface of the frame, the frame, the first space portion forming a first back pressure space together with the orbiting scroll, and
 wherein a sealing member for sealing the first back pressure space is provided between the inner circumferential surface of the frame shaft hole and the outer circumferential surface of the rotation shaft.   
     
     
         6 . The compressor of  claim 1 , wherein the fixed scroll includes a first bearing for supporting a first bearing portion of the rotation shaft, the casing includes a second bearing for supporting a second bearing portion of the rotation shaft, and the orbiting scroll includes a third bearing for supporting an eccentric portion of the rotation shaft, and
 wherein the first bearing includes one of a bush bearing or a needle bearing, the second bearing includes one of a bush bearing or a ball bearing, and the third bearing includes a bush bearing.   
     
     
         7 . The compressor of  claim 1 , wherein the rotation shaft includes a first bearing portion formed on the one end portion of the rotation shaft and supported by the fixed scroll, a second bearing portion formed on the another end portion of the rotation shaft and supported by the casing, and an eccentric portion formed between the first bearing portion and the second bearing portion, the eccentric portion configured to be eccentrically coupled through the orbiting scroll, and
 wherein a balance weight is coupled between the second bearing portion and the eccentric portion of the rotation shaft, and supported in the axial direction by being in contact with the frame.   
     
     
         8 . The compressor of  claim 7 , wherein the frame includes a first space portion formed on one side surface thereof, the first space portion forming a first back pressure space together with the orbiting scroll, and
 wherein the first space portion includes a bearing supporting protrusion protruding in the axial direction toward the balance weight, the bearing supporting protrusion forming a bearing surface with the balance weight in the axial direction.   
     
     
         9 . The compressor of  claim 8 , wherein the rotation shaft includes an axial supporting surface formed on an outer circumferential surface thereof in a stepped manner to support the balance weight in the axial direction. 
     
     
         10 . The compressor of  claim 1 , wherein the casing includes a second shaft supporting portion protruding therefrom in a direction toward the driving motor, the another end portion of the rotation shaft being rotatably inserted in the second shaft supporting portion, and
 wherein the second shaft supporting portion includes a second space portion spaced apart from an end portion of the rotation shaft, the second space portion configured to store a portion of oil discharged from the compression chamber.   
     
     
         11 . The compressor of  claim 10 , wherein the casing includes an oil storage portion configured to store oil which is discharged together with a refrigerant from the compression chamber and then separated from the refrigerant, and
 wherein the oil storage portion includes an oil supply passage formed between the oil storage portion and the another end portion of the rotation shaft, the oil supply passage being configured to guide the oil from the oil storage portion to a bearing surface.   
     
     
         12 . The compressor of  claim 11 , wherein the oil supply passage includes at least one pressure-reducing portion. 
     
     
         13 . The compressor of  claim 1 , wherein the casing includes a second shaft supporting portion protruding therefrom in a direction toward the driving motor, the another end portion of the rotation shaft being rotatably inserted in the second shaft supporting portion, and
 wherein at least a portion of the second shaft supporting portion axially overlaps a coil wound around the stator.   
     
     
         14 . The compressor of  claim 1 , wherein the frame includes a first space portion configured to form a first back pressure space together with the orbiting scroll, and
 wherein the first space portion axially overlaps at least part of a coil wound around the stator.   
     
     
         15 . The compressor of  claim 1 , wherein the rotation shaft includes a balance weight coupled to the rotation shaft, and
 wherein the balance weight axially overlaps at least part of a coil wound around the stator.   
     
     
         16 . A motor operated compressor, comprising:
 a driving motor having a rotation shaft;   a frame having a frame shaft hole, the rotation shaft rotatably passing through the frame shaft hole;   an orbiting scroll supported on the frame in an axial direction and having a rotation shaft coupling portion, the rotation shaft passing through the orbiting scroll and being eccentrically coupled to the orbiting scroll;   a fixed scroll provided at an opposite side of the frame with the orbiting scroll interposed therebetween, the fixed scroll forming a compression chamber together with the orbiting scroll, the fixed scroll having a scroll shaft hole, the rotation shaft rotatably passing through the scroll shaft hole;   a first shaft supporting portion provided on an inner surface of the casing forming a discharge space together with the fixed scroll, as the first shaft supporting portion being configure to support one end portion of the rotation shaft; and   a second shaft supporting portion provided at an opposite side of the frame with the driving motor interposed therebetween, the second shaft supporting portion being configured to support another end portion of the rotation shaft.   
     
     
         17 . A motor operated compressor, comprising:
 a casing extending from adjacent a first side to adjacent a second side;   a driving motor disposed in the casing;   a frame disposed in the casing between the second side and the driving motor;   a fixed scroll disposed in the casing between the second side and the frame;   an orbiting scroll disposed in the casing between the fixed scroll and the frame, the fixed scroll and the orbiting scroll forming a compression chamber; and   a rotation shaft supported by the casing adjacent the first side and by the fixed scroll adjacent the second side, the rotation shaft being eccentrically coupled to the driving motor.   
     
     
         18 . The motor operated compressor of  claim 17 , further including:
 a first shaft supporting portion protruding axially from the fixed scroll towards the second side;   a first bearing disposed between the rotation shaft and an inner circumferential surface of the first shaft supporting portion;   a second shaft supporting portion protruding from axially from the casing towards the second side; and   a second bearing disposed between the rotation shaft and an inner circumferential surface of the second shaft supporting portion.   
     
     
         19 . The motor operated compressor of  claim 18 , further including:
 an oil supply passage extending from a first end of the rotation shaft disposed adjacent the first scroll towards a second end of the rotation shaft disposed adjacent the casing; and   at least one oil supply hole in fluid communication with the oil supply passage, the at least one oil supply hole configured to supply oil from the oil supply passage to one of the first bearing or the second bearing.   
     
     
         20 . The motor operated compressor of  claim 17 , wherein
 the frame includes a frame shaft hole, and   the rotation shaft is rotatably disposed within the frame shaft hole, the rotation shaft being separated from the frame by a circumferential gap.