Refrigerator

Abstract

A refrigerator includes an inner case defining a storage chamber; a cold-air duct for guiding air flowing in the storage chamber and forming a heat exchange space, together with the inner case; an evaporator positioned in the heat exchange space; a bypass passage disposed at the cold-air duct and allowing air to flow while bypassing the evaporator; a sensor disposed in the bypass passage and having an output value which changes according to the flow rate of the air flowing through the bypass passage; a defroster for removing frost generated on a surface of the evaporator; and a controller for controlling the defroster on the basis of the value output by the sensor.

1 . A refrigerator comprising:
 an inner case defining a storage space;   a cool air duct to guide a flow of air within the storage space, the cool air duct defining a heat-exchange space together with the inner case;   an evaporator disposed in the heat-exchange space;   a bypass passage disposed at the cool air duct, the bypass passage providing for a portion of the air flow to bypass the evaporator;   a sensor disposed in the bypass passage, the sensor having an output value varying according to a flow rate of the portion of the air flowing through the bypass passage;   a defroster to remove frost generated on a surface of the evaporator; and   a controller configured to control the defroster based on the output value of the sensor.   
     
     
         2 . The refrigerator of  claim 1 , wherein the sensor comprises:
 a heat generating element;   a sensing element to sense a temperature of the heat generating element; and   a sensor printed circuit board (PCB) on which the heat generating element and the sensing element are installed.   
     
     
         3 . The refrigerator of  claim 2 , wherein, when a difference value between a temperature sensed by the sensing element in a state in which the heat generating element is turned on and a temperature sensed by the sensing element in a state in which the heat generating element is turned off is equal to or less than a reference temperature value, the controller is configured to operate the defroster. 
     
     
         4 . The refrigerator of  claim 2 , wherein the sensor further comprises a sensor housing surrounding the heat generating element, the sensing element, and the sensor PCB. 
     
     
         5 . The refrigerator of  claim 1 , further comprising a passage cover to cover the bypass passage so as to partition the bypass passage from the heat exchange space. 
     
     
         6 . The refrigerator of  claim 5 , wherein the cool air duct comprises an elongated extension surface that is a surface in which the bypass passage is defined, and
 the passage cover comprises:   a cover plate to cover the bypass passage; and   a barrier extending from the cover plate, the barrier protruding downward from the elongated extension surface in a state in which the cover plate covers the bypass passage.   
     
     
         7 . The refrigerator of  claim 6 , wherein the bypass passage extends along the elongated extension surface in a straight-line shape. 
     
     
         8 . The refrigerator of  claim 6 , wherein the barrier further comprises:
 a rear barrier continuously extending from the cover plate, the rear barrier being disposed adjacent to the evaporator;   a plurality of side barriers extending from the rear barrier, the plurality of side barriers being spaced apart from each other in a left and right direction; and   a front barrier connected to the plurality of side barriers, spaced apart from the rear barrier, and disposed at an opposite side of the evaporator with respect to the rear barrier.   
     
     
         9 . The refrigerator of  claim 8 , wherein the barrier has an opened bottom surface, and
 the front barrier, the plurality of side barriers, and the rear barrier define a guide passage to guide the portion of the air to the bypass passage.   
     
     
         10 . The refrigerator of  claim 8 , wherein the cool air duct further comprises an inclined surface extending to be inclined from an end of the elongated extension surface and to guide the air towards the evaporator, and
 a slot provided at the rear barrier to define a passage for allowing the air flowing along the inclined surface to flow towards the evaporator.   
     
     
         11 . The refrigerator of  claim 5 , wherein the cool air duct comprises a bottom wall and two sidewalls, which define the bypass passage,
 the passage cover comprises a cover plate to cover the bypass passage in a state of being spaced apart from the bottom wall, and   the sensor is disposed to be spaced apart from the bottom wall and the cover plate in the bypass passage.   
     
     
         12 . The refrigerator of  claim 11 , wherein the sensor is disposed to be spaced apart from an inlet and an outlet of the bypass passage, and
 the sensor is disposed at a point at which a distance between the bottom wall and the cover plate is bisected in the bypass passage.   
     
     
         13 . The refrigerator of  claim 12 , wherein the sensor is disposed closer to the outlet than the inlet of the bypass passage. 
     
     
         14 . The refrigerator of  claim 5 , wherein at least a portion of the bypass passage and the passage cover is disposed to face the evaporator within a range of a left and right width of the evaporator. 
     
     
         15 . The refrigerator of  claim 5 , wherein a blower fan is disposed at the cool air duct,
 a cool air inflow hole into which the air is introduced is defined in the cool air duct, and   the bypass passage does not overlap with the cool air inflow hole in a vertical direction.   
     
     
         16 . The refrigerator of  claim 15 , wherein an outlet of the bypass passage is disposed in a region outside of a limit region having a diameter greater than a diameter of the blower fan with respect to a center of the blower fan. 
     
     
         17 . The refrigerator of  claim 16 , wherein the outlet of the bypass passage is disposed higher than an upper end of the evaporator. 
     
     
         18 . The refrigerator of  claim 16 , wherein the limit region has a diameter set to 1.5 times or more than the diameter of the blower fan. 
     
     
         19 . The refrigerator of  claim 1 , further comprising a blocking rib to block an introduction of liquid into the bypass passage and disposed above the bypass passage in the cool air duct. 
     
     
         20 . The refrigerator of  claim 19 , wherein the blocking rib has a left-right minimum length greater than a left-right minimum width of the bypass passage, and
 the entire bypass passage in the left and right direction is disposed to overlap the blocking rib in the vertical direction.