Blower

A blower apparatus comprising:

• a main frame of a box-like shape provided with a main-frame inlet port and a main-frame outlet port in side surfaces confronting each other, the main-frame inlet port for taking in air and the main-frame outlet port for delivering the air;
• a plurality of centrifugal blower units for suctioning the air taken inside of the main frame from the main-frame inlet port, through a blower inlet port, and for discharging the air from a blower air outlet toward the main-frame outlet port;
• and
• a sound absorbing material for absorbing airflow noise, the sound absorbing material disposed on a back plate at the centrifugal blower unit confronting the main-frame inlet port, fixed to a sound absorbing material fixing plate, attached in a removable manner to the back plate at the centrifugal blower unit confronting the main-frame inlet port, and is of a triangular shape in cross section, and disposed with a tip pointing to the main-frame inlet port,
• wherein the main frame is provided with a maintenance opening in one of surfaces other than the side surfaces having the main-frame inlet port and the main-frame outlet port for the purpose of checking the inside of the main frame,
• the plurality of centrifugal blower units are disposed one another in a direction toward the maintenance opening in a manner that a difference in discharging spatial distances from the blower air outlets of the adjoining centrifugal blower units to the main-frame outlet port is equal to or greater than an outer diameter of an impeller of the centrifugal blower unit located nearest to the maintenance opening.

A blower apparatus comprising:

• a main frame of a box-like shape provided with a main-frame inlet port and a main-frame outlet port in side surfaces confronting each other, the main-frame inlet port for taking in air and the main-frame outlet port for delivering the air;
• and
• a plurality of centrifugal blower units for suctioning the air taken inside of the main frame from the main-frame inlet port, through a blower inlet port, and for discharging the air from a blower air outlet toward the main-frame outlet port,
• wherein the main frame is provided with a maintenance opening in one of surfaces other than the side surfaces having the main-frame inlet port and the main-frame outlet port, and
• the main frame is provided with a partition plate having a plurality of openings corresponding to the plurality of centrifugal blower units, the partition plate arranged facing main-frame outlet port and includes an offset portion between the plurality of centrifugal blower units, and
• the plurality of centrifugal blower units are disposed one another in a direction toward the maintenance opening in a manner that a difference in discharging spatial distances from the blower air outlets of the adjoining centrifugal blower units to the main-frame outlet port is equal to or greater than an outer diameter of an impeller of the centrifugal blower unit located nearest to the maintenance opening;
• wherein at least two sets of the plurality of centrifugal blower units are disposed in a manner that a scroll-casing outlet end facing the main-frame outlet port of one of the centrifugal blower units located further from the maintenance opening and a scroll-casing inlet end facing the main-frame inlet port of the other centrifugal blower unit located nearer to the maintenance opening are overlapped along a direction of airflow in the main frame.