Blower and method for molding housing thereof

A blower which sucks air inside an annular wall through slits as a fan rotates, the annular wall being formed away from the ends of fan blades, and the slits, passing from a circular inner perimeter to a non-circular outer perimeter of the annular wall, being formed in sections of the annular wall which are opposite to the ends of the fan blades,

• wherein the flow rate of air flowing inside the annular wall through the slits is made constant all around the annular wall by continuously or intermittently changing the width of said slits, w, according to the radial length between the inner and outer perimeters of the annular wall, L, so that the condition represented by the following equation is met:
• w3/L=constant.

A blower which sucks air inside an annular wall through slits as a fan rotates, the annular wall being formed away from the ends of fan blades, and the slits, passing from a circular inner perimeter to a non-circular outer perimeter of the annular wall, being formed in sections of the annular wall which are opposite to said ends of the fan blades,

• wherein the flow rate of air flowing inside the annular wall through the slits is made constant all around the annular wall by changing the width of said slits, w, and the number of slits in the direction of the axis of rotation, n, where n is a positive integer, according to the radial length between the inner and outer perimeters of the annular wall, L, so that the condition represented by the following equation is met:
• n·w3/L=constant.

A blower which is arranged to suck air inside an annular wall through slits as a fan rotates, the annular wall being formed away from the ends of fan blades, and the slits, passing from the inner perimeter to the outer perimeter of the annular wall at a section which corresponds to the ends of the fan blades, being formed in sections of the annular wall which are opposite to said ends of the fan blades,

• wherein the annular wall with the slits is formed by stacking a plurality of annular plates in a spaced relation from each other through spacers in the direction of the axis of rotation of the fan, and the annular plate that is located at the most upstream side of the main air flow produced by the fan rotation has the largest thickness among all the annular plates.

A blower which is arranged to suck air inside an annular wall through slits as a fan rotates, the annular wall being formed away from the ends of fan blades, and the slits, passing from the inner perimeter to the outer perimeter of the annular wall at a section which corresponds to the ends of the fan blades, being formed in sections of the annular wall which are opposite to said ends of the fan blades,

• wherein the annular wall with the slits is formed by stacking a plurality of annular plates in a spaced relation from each other through spacers in the direction of the axis of rotation of the fan, and the annular plate that is located at the most upstream side of the main air flow produced by the fan rotation has the largest thickness among all the annular plates, and wherein the annular plate that is located at the most upstream side of the main air flow produced by the fan rotation is formed by cutting the upstream-side end surface of the inner perimeter so that the perimeter becomes thin.

A blower which is arranged to suck air inside an annular wall through slits as a fan rotates, the annular wall being formed away from the ends of fan blades, and the slits, passing from the inner perimeter to the outer perimeter of the annular wall at a section which corresponds to the ends of the fan blades, being formed in sections of the annular wall which are opposite to said ends of fan blades,

• wherein the clearance between the end of a fan blade and the inner perimeter of the annular wall becomes wider as it gets farther away from a bearing support.