Scroll compressor and air conditioner having the same

Abstract

A scroll compressor includes a casing, a drive motor, an orbiting scroll, a fixed scroll engaged with the orbiting scroll, a back pressure chamber proximate to the orbiting scroll, an inlet pipe for supplying refrigerant to a compression chamber formed by the orbiting scroll and the fixed scroll, and a discharge pipe for discharging the refrigerant discharged from the compression chamber. The scroll compressor includes an oil feed passage configured to connect the back pressure chamber and an oil storage tank provided in the casing so that oil of the oil storage tank is supplied to the back pressure chamber; and a flow control valve disposed in the oil feed passage and configured to control an amount of oil to be supplied to the back pressure chamber via the oil feed passage according to a suction pressure, a discharge pressure, and a rotational velocity.

What is claimed is: 
     
         1 . A scroll compressor which comprises a casing, a drive motor accommodated in the casing, an orbiting scroll to be rotated by the drive motor, a fixed scroll engaged with the orbiting scroll, a back pressure chamber provided proximate to the orbiting scroll, an inlet pipe that is disposed in the casing and supplies refrigerant to a compression chamber formed by the orbiting scroll and the fixed scroll, and a discharge pipe that is disposed in the casing and discharges the refrigerant discharged from the compression chamber outside the casing, the scroll compressor comprising:
 an oil feed passage configured to connect the back pressure chamber and an oil storage tank provided in the casing so that oil of the oil storage tank is supplied to the back pressure chamber; and   a flow control valve disposed in the oil feed passage, the flow control valve configured to control an amount of oil to be supplied to the back pressure chamber via the oil feed passage,   wherein the flow control valve controls the amount of oil to be supplied via the oil feed passage in accordance with a suction pressure of the refrigerant to be sucked through the inlet pipe, a discharge pressure of the refrigerant to be discharged through the discharge pipe, and a rotational velocity of the drive motor.   
     
     
         2 . The scroll compressor of  claim 1 , wherein
 the flow control valve is configured to control an opening area of the oil feed passage.   
     
     
         3 . The scroll compressor of  claim 1 , wherein
 the scroll compressor is disposed in an outdoor unit of an air conditioner, and   the flow control valve is controlled by a controller of the air conditioner.   
     
     
         4 . The scroll compressor of  claim 1 , further comprising:
 a main frame configured to support the orbiting scroll and provided with the back pressure chamber,   wherein the main frame is provided with an oil feed hole connected to a discharge end of the oil feed passage.   
     
     
         5 . The scroll compressor of  claim 4 , wherein the oil feed hole comprises:
 a vertical hole which is connected to the back pressure chamber and is parallel to a drive shaft of the drive motor; and   a horizontal hole which is formed perpendicular to the vertical hole and is connected to the discharge end of the oil feed passage.   
     
     
         6 . The scroll compressor of  claim 1 , wherein,
 when the drive motor is rotated at a low speed, the flow control valve increases an amount of oil passing through the oil feed passage so that a back pressure of the back pressure chamber is a value between the suction pressure and the discharge pressure.   
     
     
         7 . The scroll compressor of  claim 1 , wherein,
 when the discharge pressure of the scroll compressor is maximum, the flow control valve cuts off the oil feed passage.   
     
     
         8 . A scroll compressor which comprises a casing, a drive motor accommodated in the casing, an orbiting scroll to be rotated by the drive motor, a fixed scroll engaged with the orbiting scroll, a back pressure chamber proximate to the orbiting scroll, an inlet pipe that is disposed in the casing and supplies refrigerant to a compression chamber formed by the orbiting scroll and the fixed scroll, a discharge pipe that is disposed in the casing and discharges the refrigerant discharged from the compression chamber outside the casing, and an oil separator that is connected to the discharge pipe, and separates and collects oil from the discharged refrigerant, the scroll compressor comprising:
 an oil feed passage configured to connect the oil separator and the back pressure chamber so that oil collected in the oil separator is supplied to the back pressure chamber; and   a flow control valve disposed in the oil feed passage, the flow control valve configured to control an amount of oil to be supplied to the back pressure chamber via the oil feed passage,   wherein the flow control valve controls the amount of oil to be supplied via the oil feed passage in accordance with a suction pressure of the refrigerant to be sucked through the inlet pipe, a discharge pressure of the refrigerant to be discharged through the discharge pipe, and a rotational velocity of the drive motor.   
     
     
         9 . The scroll compressor of  claim 8 , wherein
 the flow control valve is configured to control an opening area of the oil feed passage.   
     
     
         10 . The scroll compressor of  claim 8 , wherein
 the scroll compressor is disposed in an outdoor unit of an air conditioner, and   the flow control valve is controlled by a controller of the air conditioner.   
     
     
         11 . The scroll compressor of  claim 8 , further comprising:
 a main frame configured to support the orbiting scroll and provided with the back pressure chamber,   wherein the main frame is provided with an oil feed hole connected to a discharge end of the oil feed passage.   
     
     
         12 . The scroll compressor of  claim 11 , wherein the oil feed hole comprises:
 a vertical hole which is connected to the back pressure chamber and is parallel to a drive shaft of the drive motor; and   a horizontal hole which is formed perpendicular to the vertical hole and is connected to the discharge end of the oil feed passage.   
     
     
         13 . The scroll compressor of  claim 8 , wherein,
 when the drive motor is rotated at a low speed, the flow control valve increases an amount of oil passing through the oil feed passage so that a back pressure of the back pressure chamber is a value between the suction pressure and the discharge pressure.   
     
     
         14 . The scroll compressor of  claim 8 , wherein,
 when the discharge pressure of the scroll compressor is maximum, the flow control valve cuts off the oil feed passage.   
     
     
         15 . A scroll compressor which comprises a casing, a drive motor accommodated in the casing, an orbiting scroll to be rotated by the drive motor, a fixed scroll engaged with the orbiting scroll, a back pressure chamber proximate to the orbiting scroll, an inlet pipe that is disposed in the casing and supplies refrigerant to a compression chamber formed by the orbiting scroll and the fixed scroll, and a discharge pipe that is disposed in the casing and discharges the refrigerant discharged from the compression chamber outside the casing, the scroll compressor comprising:
 an oil feed passage configured to connect the compression chamber and an oil storage tank provided in the casing so that oil of the oil storage tank is supplied to the compression chamber; and   a flow control valve disposed in the oil feed passage, the flow control valve configured to control an amount of oil to be supplied to the compression chamber via the oil feed passage,   wherein the flow control valve controls the amount of oil to be supplied via the oil feed passage in accordance with a suction pressure of the refrigerant to be sucked through the inlet pipe, a discharge pressure of the refrigerant to be discharged through the discharge pipe, and a rotational velocity of the drive motor.   
     
     
         16 . The scroll compressor of  claim 15 , wherein
 the fixed scroll comprises an auxiliary oil feed hole connecting the compression chamber and a discharge end of the oil feed passage.   
     
     
         17 . The scroll compressor of  claim 15 , wherein
 the scroll compressor is disposed in an outdoor unit of an air conditioner, and   the flow control valve is controlled by a controller of the air conditioner.   
     
     
         18 . The scroll compressor of  claim 15 , wherein,
 when the drive motor is rotated at a low speed, the flow control valve increases an amount of oil passing through the oil feed passage.   
     
     
         19 . A scroll compressor which comprises a casing, a drive motor accommodated in the casing, an orbiting scroll to be rotated by the drive motor, a fixed scroll engaged with the orbiting scroll, a back pressure chamber proximate to the orbiting scroll, an inlet pipe that is disposed in the casing and supplies refrigerant to a compression chamber formed by the orbiting scroll and the fixed scroll, a discharge pipe that is disposed in the casing and discharges the refrigerant discharged from the compression chamber outside the casing, and a vapor refrigerant injection pipe, the scroll compressor comprising:
 an oil feed passage configured to connect an oil storage tank provided in the casing and the vapor refrigerant injection pipe so that oil in the oil storage tank is supplied to the compression chamber through the vapor refrigerant injection pipe; and   a flow control valve disposed in the oil feed passage, the flow control valve configured to control an amount of oil to be supplied to the vapor refrigerant injection pipe via the oil feed passage,   wherein the flow control valve controls the amount of oil to be supplied via the oil feed passage in accordance with a suction pressure of the refrigerant to be sucked through the inlet pipe, a discharge pressure of the refrigerant to be discharged through the discharge pipe, and a rotational velocity of the drive motor.   
     
     
         20 . An air conditioner comprising:
 an outdoor unit in which a scroll compressor is disposed; and   a controller configured to control the scroll compressor in accordance with set conditions,   wherein the scroll compressor comprises a casing, a drive motor accommodated in the casing, an orbiting scroll to be rotated by the drive motor, a fixed scroll engaged with the orbiting scroll, a back pressure chamber proximate to the orbiting scroll, an inlet pipe that is disposed in the casing and supplies refrigerant to a compression chamber formed by the orbiting scroll and the fixed scroll, and a discharge pipe that is disposed in the casing and discharges the refrigerant discharged from the compression chamber outside the casing,   wherein the scroll compressor comprises,
 an oil feed passage configured to connect the back pressure chamber and an oil storage tank provided in the casing so that oil of the oil storage tank is supplied to the back pressure chamber; and 
 a flow control valve disposed in the oil feed passage, the flow control valve configured to control an amount of oil to be supplied to the back pressure chamber via the oil feed passage, and 
 wherein the flow control valve controls the amount of oil to be supplied via the oil feed passage in accordance with a suction pressure of the refrigerant to be sucked through the inlet pipe, a discharge pressure of the refrigerant to be discharged through the discharge pipe, and a rotational velocity of the drive motor. 
   
     
     
         21 . A scroll compressor, comprising:
 a fixed scroll of the scroll compressor engaged with an orbiting scroll;   a back pressure chamber proximate to the orbiting scroll and connected to an oil source by an oil feed passage so that oil is supplied to the back pressure chamber;   a flow control valve disposed in the oil feed passage and configured to control an amount of oil to be supplied to the back pressure chamber via the oil feed passage in accordance with a suction pressure of refrigerant to be sucked through an inlet pipe, a discharge pressure of the refrigerant to be discharged through a discharge pipe, and a rotational velocity of a drive motor that rotates the orbiting scroll.   
     
     
         22 . The scroll compressor of  claim 21 , wherein
 the flow control valve is configured to control the amount of oil to be supplied to the back pressure chamber.   
     
     
         23 . The scroll compressor of  claim 21 , wherein
 the scroll compressor is disposed in an air conditioner, and   the flow control valve is controlled by a controller of the air conditioner.   
     
     
         24 . The scroll compressor of  claim 21 , wherein,
 the flow control valve maintains a back pressure of the back pressure chamber between the suction pressure and the discharge pressure when the drive motor is rotated at a low speed.   
     
     
         25 . The scroll compressor of  claim 21 , wherein,
 the flow control valve cuts off the oil feed passage when the discharge pressure of the scroll compressor reaches a maximum.   
     
     
         26 . The scroll compressor of  claim 21 , wherein
 the flow control valve is configured to supply oil to the back pressure chamber via the oil feed passage when a ratio of the discharge pressure to the suction pressure is 2 or less and the rotational velocity of the drive motor is 30 revolutions per second or less.   
     
     
         27 . The scroll compressor of  claim 21 , wherein,
 the flow control valve comprises an electronic proportional solenoid valve.   
     
     
         28 . An air conditioner having a scroll compressor, comprising:
 a fixed scroll of the scroll compressor engaged with an orbiting scroll;   a back pressure chamber proximate to the orbiting scroll and connected to an oil source by an oil feed passage so that oil is supplied to the back pressure chamber;   a flow control valve disposed in the oil feed passage and configured to control an amount of oil to be supplied to the back pressure chamber via the oil feed passage in accordance with a suction pressure of refrigerant to be sucked through an inlet pipe, a discharge pressure of the refrigerant to be discharged through a discharge pipe, and a rotational velocity of a drive motor that rotates the orbiting scroll.