Air-sending device of outdoor unit, outdoor unit, and refrigeration cycle apparatus

Abstract

A propeller fan rotates about a vertical axis. A bellmouth has a wall extending such that an air passage on an outlet side spreads outward. The bellmouth has a shape satisfying: H/D≧0.04 between a length H of the sloping surface in a direction of the rotation axis from an end on an inlet; side to an end on the outlet side and a fan diameter D of the propeller fan 0<θ≧60° for an angle θ formed between a line connecting the ends of the sloping surface and the rotation axis; and L/L 0 ≧0.5 between a length L in the direction of the rotation axis from an opening on the inlet side to the end of the sloping surface on the inlet side and a length L 0 of the blades of the propeller fan in the direction of the rotational axis.

1 . An air-sending device of an outdoor unit comprising:
 a propeller fan that rotates about a rotation axis extending in a direction of gravity and includes a plurality of blades that produce a flow of gas in a direction opposite to the direction of gravity; and   a bellmouth rectifying the gas, the bellmouth having an annular wall extending in a direction of rotation of the blades of the propeller fan on an outer side with respect to outer peripheral edges of the blades,   wherein, the bellmouth has a wall forming a sloping surface extending such that an air passage on an outlet side spreads outward in a case where an operating point of the propeller fan is on an open side with respect to a surging zone, and   the bellmouth has a shape satisfying conditions represented as a relationship of H/D≧0.04 between a length H of the sloping surface in a direction of the rotation axis from an end on an inlet side to an end on the outlet side and a fan diameter D of the propeller fan,   a relationship of 0<θ≧60° for an angle θ formed between a line connecting the ends of the sloping surface and the rotation axis, and   a relationship of L/L 0 ≧0.5 between a length L in the direction of the rotation axis from an opening on the inlet side to the end of the sloping surface on the inlet side and a length L 0  of the blades of the propeller fan in the direction of the rotation axis.   
     
     
         2 . The air-sending device of the outdoor unit of  claim 1 , wherein the bellmouth includes a wall extending in the direction of the rotation axis from the end of the sloping surface on the outlet side, the wall being provided at an opening on the outlet side. 
     
     
         3 . The air-sending device of the outdoor unit of  claim 1 , further comprising a fan guard having a grating that covers the opening on the outlet side,
 wherein an orientation of the grating in the direction of the rotation axis is parallel to the rotation axis.   
     
     
         4 . The air-sending device of the outdoor unit of  claim 1 , wherein the propeller fan has a rib provided on each of the blades over an entirety of an outer peripheral edge or a part of the outer peripheral edge excluding two ends thereof and extending substantially parallel to the rotation axis toward the inlet side. 
     
     
         5 . The air-sending device of the outdoor unit of  claim 1 , wherein a part of the opening of the bellmouth on the outlet side is deformed according to an area defined by dimensions of a casing of the outdoor unit. 
     
     
         6 . The air-sending device of the outdoor unit of  claim 1 , wherein the bellmouth has a curved surface provided at the opening on the inlet side and configured such that an integrated value of radii of curvature of the curved surface over an entire circumference becomes largest under conditions for provision or installation. 
     
     
         7 . An outdoor unit comprising:
 a compressor that compresses a refrigerant;
 an outdoor-side heat exchanger that exchanges heat between the refrigerant and air; and 
 the air-sending device of  claim 1  that allows the air to pass through the outdoor-side heat exchanger. 
   
     
     
         8 . A refrigeration cycle apparatus comprising:
 a load unit having a plurality of load-side heat exchangers that each exchange heat between a subject of heat exchange and a refrigerant, and flow control means that adjusts a flow rate of the refrigerant made to flow into the load-side heat exchangers; and   the outdoor unit of  claim 7 ,   wherein the load unit and the outdoor unit are connected by pipes to constitute a refrigerant circuit.