Motor-operated compressor

Abstract

A motor-operated compressor includes a casing having a sealed internal space, a first scroll fixed in the internal space, and a second scroll engaged with the first scroll to form a plurality of compression chambers. The compressor also includes a frame fixed on an opposite side of the first scroll with the second scroll interposed therebetween, and a driving motor positioned on an opposite side of the second scroll. The compressor further includes a rotary shaft coupled to the second scroll in an off-centered manner and coupled to the driving motor. The first end portion of the rotary shaft forms a fixed end supported in the radial direction by members positioned on both sides of the second scroll. The second end portion of the rotary shaft forms a free end coupled to a rotor of the driving motor.

What is claimed is: 
     
         1 . A motor-operated compressor, comprising:
 a casing having a sealed internal space;   a first scroll fixed in the internal space of the casing;   a second scroll engaged with the first scroll to form a plurality of compression chambers with the first scroll;   a frame fixed on an opposite side of the first scroll with the second scroll interposed therebetween;   a driving motor provided on an opposite side of the second scroll with the frame interposed therebetween; and   a rotary shaft having a first end portion coupled to the second scroll in an off-centered manner and a second end portion coupled to the driving motor and transmitting a rotational force from the driving motor to the second scroll,   wherein the first end portion of the rotary shaft forms a fixed end supported in a radial direction by members positioned axially on both sides of the second scroll and the second end portion of the rotary shaft forms a free end coupled to a rotor of the driving motor opposite the first end portion with respect to the frame.   
     
     
         2 . The motor-operated compressor of  claim 1 , wherein
 the first end portion of the rotary shaft is inserted into the first scroll through the frame and the second scroll, and the first end portion of the rotary shaft is supported by the frame and the first scroll in the radial direction.   
     
     
         3 . The motor-operated compressor of  claim 1 , wherein
 The first end portion of the rotary shaft is inserted into the casing through the frame, the second scroll, and the first scroll, and the first end portion of the rotary shaft is supported by the frame and the casing in the radial direction.   
     
     
         4 . The motor-operated compressor of  claim 1 , wherein
 in the driving motor, a stator surrounding the rotor is coupled to the casing, the stator is wound around with a winding coil that extends axially over a portion of the internal space of the casing, and   to an end of the second end portion of the rotary shaft is positioned within the portion of the internal space.   
     
     
         5 . The motor-operated compressor of  claim 4 , wherein
 one side surface of the casing protrudes toward the driving motor to form an inverter accommodating portion, and at least a portion of an inverter housing accommodating an inverter device is inserted into the inverter accommodating portion.   
     
     
         6 . The motor-operated compressor of  claim 5 , wherein
 at least a portion of the inverter accommodating portion is positioned within the portion of the internal space.   
     
     
         7 . The motor-operated compressor of  claim 6 , further including
 an intake port communicating with a suction tube and with the portion of the internal space of the casing, and the intake port overlaps the portion of the internal space occupied by the inverter accommodating portion.   
     
     
         8 . The motor-operated compressor of  claim 1 , wherein
 the rotary shaft has an oil supply recess having a predetermined length, the oil supply recess extending in an axial direction from an end of the first end portion, and   the compressor further includes a plurality of axially spaced oil supply holes formed in the oil supply recess.   
     
     
         9 . The motor-operated compressor of  claim 8 , further including a decompression bar positioned in the oil supply recess. 
     
     
         10 . The motor-operated compressor of  claim 1 , further including:
 a first orbiting wrap and a second orbiting wrap formed on opposite axial sides of the second scroll;   a first fixed wrap formed in the first scroll and configured to be engaged with the first orbiting wrap to form a first compression space; and   a second fixed wrap formed in the frame and configured to be engaged with the second orbiting wrap to form a second compression space.   
     
     
         11 . The motor-operated compressor of  claim 10 , wherein
 the internal space of the casing is divided into a first space including the driving motor and a second space disposed opposite to the first space with respect to the frame, and   the compressor includes discharge ports respectively formed at the frame and the first scroll such that a refrigerant compressed in the first and the second compression spaces is discharged toward the first space and the second space of the casing.   
     
     
         12 . The motor-operated compressor of  claim 11 , wherein
 the frame includes a discharge guide separated from the first space and configured to guide the refrigerant discharged from the discharge port to the second space.   
     
     
         13 . The motor-operated compressor of  claim 10 , further including:
 a plurality of pin holes formed in the second scroll; and   a pin member fixedly coupled to the first scroll and extending through the pin holes, the pin member configured to form an anti-rotation portion of the second scroll.   
     
     
         14 . The motor-operated compressor of  claim 13 , further including
 a plurality of protrusions extending in a radial direction from an outer circumferential surface of the second scroll, the pin holes being formed in the plurality of protrusions.   
     
     
         15 . A motor-operated compressor comprising:
 a casing having a sealed internal space;   a first scroll fixed in the internal space of the casing;   a second scroll engaged with the first scroll to form a plurality of compression chambers with the first scroll;   a frame fixed on an opposite side of the first scroll with the second scroll interposed therebetween;   a driving motor provided on an opposite side of the second scroll with the frame interposed therebetween; and   a rotary shaft transmitting a rotational force from the driving motor to the second scroll,   wherein the rotary shaft is supported in a radial direction on both sides of the second scroll.   
     
     
         16 . The motor-operated compressor of  claim 15 , wherein
 a first end portion of the rotary shaft has an eccentric portion coupled to the second scroll in an off-centered manner, and   the compressor further includes a first bearing portion axially spaced apart from a second bearing portion, the first and second bearing portions positioned on opposite sides of the eccentric portion,   the first bearing portion and the second bearing portion having the same axial central line, and   the eccentric portion having an axial central line different from the axial central line of the first bearing portion and the second bearing portion.   
     
     
         17 . The motor-operated compressor of  claim 16 , wherein
 the first scroll has a bearing accommodating protrusion extending toward the casing and accommodating the second bearing portion of the rotary shaft.   
     
     
         18 . The motor-operated compressor of  claim 16 , wherein
 the casing has a bearing accommodating protrusion extending toward the first scroll and accommodating the second bearing portion of the rotary shaft.   
     
     
         19 . The motor-operated compressor of  claim 16 , wherein
 at least one of the first bearing portion and the second bearing portion includes a bush bearing.