Device for introducing and discharging cooling air
AssigneeZexel Corporation
InventorsToshio Tsubakida, Yoshinori Hashimoto
Life of this patent
Estimating the term…
Abstract
The object of the invention is to prevent the quantity of airflow by a fan from decreasing in dependence on the distance between the fan and obstacles such as an engine in a device for introducing and discharging cooling air having a shroud with a high covering rate. In the device for introducing and discharging cooling air having the shroud with the high covering rate, an airflow direction changing member is provided downstream of the fan, and each fixed blade of the member has a shift angle in the radial direction and an attack angle in a rotation direction of the fan, so that the air tends to be discharged outward in the radial direction.
Claims24
A device for introducing cooling air through a heat exchanger and for discharging the cooling air, said device comprising:
- a fan including rotatable blades rotatable about a rotation axis, and a fan motor operably coupled to said rotatable blades;
- a shroud for forming an airflow passage from the heat exchanger to said fan;
- an airflow direction changing member provided downstream of said fan;
- wherein said airflow direction changing member comprises a center boss portion and a plurality of fixed blades having radially inner ends secured on said boss portion, said fixed blades radiate from said center boss portion in a generally radial direction, said fixed blades have radially outer ends fixed together in a circumferential series, and said fixed blades are fixed in position such that said rotatable blades are rotatable about said rotation axis relative to said fixed blades;
- wherein each of said fixed blades has a shift angle constituted by an angle between a first datum line extending from a center of said boss portion through a center of said radially inner end of said fixed blade and a second datum line extending from said center of said boss portion through a center of a radially outer end of said fixed blade, said second datum line being circumferentially advanced relative to said first datum line in a rotation direction of said fan;
- wherein each of said fixed blades has an attack angle constituted by an angle between a third datum line extending along a chord of an airflow directing surface of said fixed blade in the rotation direction of said fan and a datum surface extending along the rotation direction of said fan, such that said fixed blades redirect at least part of the cooling air discharged in an axial direction from said fan in an outward radial direction along said fixed blades;
- wherein each of said fixed blades has a first portion extending along said first datum line from said radially inner end to a bend portion and a second portion extending from said bend portion on said first datum line to said radially outer end;
- and
- wherein said second portion constitutes at least 40% of an entire length of said fixed blade.
A device for introducing cooling air through a heat exchanger and for discharging the cooling air, said device comprising:
- a fan including rotatable blades rotatable about a rotation axis, and a fan motor operably coupled to said rotatable blades;
- a shroud for forming an airflow passage from the heat exchanger to said fan;
- an airflow direction changing member provided downstream of said fan;
- wherein said airflow direction changing member comprises a center boss portion and a plurality of fixed blades having radially inner ends secured on said boss portion, said fixed blades radiate from said center boss portion in a generally radial direction, said fixed blades have radially outer ends fixed together in a circumferential series, and said fixed blades are fixed in position such that said rotatable blades are rotatable about said rotation axis relative to said fixed blades;
- wherein each of said fixed blades has a shift angle constituted by an angle between a first datum line extending from a center of said boss portion through a center of said radially inner end of said fixed blade and a second datum line extending from said center of said boss portion through a center of a radially outer end of said fixed blade, said second datum line being circumferentially advanced relative to said first datum line in a rotation direction of said fan;
- wherein each of said fixed blades has an attack angle constituted by an angle between a third datum line extending along a chord of an airflow directing surface of said fixed blade in the rotation direction of said fan and a datum surface extending along the rotation direction of said fan, such that said fixed blades redirect at least part of the cooling air discharged in an axial direction from said fan in an outward radial direction along said fixed blades;
- and
- wherein each of said fixed blades is straight from said radially inner end to said radially outer end.
Dependencies are inferred from the claim text.