Abstract: A centrifugal fan includes a casing side plate with a casing inlet, a spiral scroll, a tongue, a casing outlet, a main plate, a retaining ring, multiple blades arranged between the main plate and the retaining ring, and an air-intake space surrounded by the blades. The centrifugal fan further includes an airflow accelerator in the air-intake space for increasing an airflow speed of a gas toward the blades.

Abstract: Centrifugal fan includes casing and impeller, and discharge duct is connected to casing. At least one of tongue-part-side wall surface on tongue part side extending from casing outlet of casing and opposite tongue-part-side wall surface on side opposite to tongue part side extending from casing outlet protrudes into the inside of discharge duct, and outlet gas flow is bent at predetermined angle and is formed into discharge duct internal gas flow.

Abstract: A centrifugal blower unit comprising an impeller disposed therein and a scroll casing covering the exterior, the scroll casing having an outlet port, a tongue-like portion, a scroll portion of a volute shape and side casing plates provided with inlet ports on both sides, featuring advantages of increasing a static pressure and reducing an input power and noise while also achieving compactness in size. The scroll portion is provided with tapered scroll walls formed in anti-tongue-side wall adjacent to the outlet port by having it bent along bent lines toward the impeller and at angles to a driving shaft of the impeller such that a cross sectional area of the scroll portion in a direction of the driving shaft becomes gradually smaller toward the side casing plates.

Abstract: A fan with a sound deadening box has in its body a double inlet centrifugal fan and an inlet-port sound absorber formed between the fan and a body air inlet. The fan further includes a casing-inlet-port-side air passage and triangular prism shaped first inlet-port-sound-absorber air passage. With this structure, the fan has a low pressure loss, a low input, high static pressure, and a low level of airflow collision noise.

Abstract: A centrifugal fan includes a casing side plate with a casing inlet, a spiral scroll, a tongue, a casing outlet, a main plate, a retaining ring, multiple blades arranged between the main plate and the retaining ring, and an air-intake space surrounded by the blades. The centrifugal fan further includes an airflow accelerator in the air-intake space for increasing an airflow speed of a gas toward the blades.

Abstract: A blower apparatus comprises a box-like main frame provided with a main-frame inlet port and a main-frame outlet port in positions confronting each other, and a plurality of centrifugal blower units for suctioning through a blower inlet port air taken inside of the main frame from the main-frame inlet port and discharging the air from a blower air outlet toward the main-frame outlet port. The main frame is provided with a maintenance opening in one of the surfaces other than the surfaces having the main-frame inlet port and the main-frame outlet port for the purpose of checking the inside of the main frame, and the plurality of centrifugal blower units are disposed one another in a direction toward the maintenance opening so 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.

Abstract: A control device accommodating unit (15) is provided in a section (50) accommodating an indoor air blower (7) adjacently to an indoor air flow-in port (16), and an impeller (7c) of the indoor air blower (7) is sequentially opposite to the indoor air flow-in port (16) and the control device accommodating unit (15) by rotation of the impeller (7c), and a space (51) is formed between the indoor air flow-in port (16) and the control device accommodating unit (15). In this configuration, it is possible to obtain a cooling device decreased in drop of air flow rate and drop of cooling performance due to mounting a control device (14).

Abstract: A double inlet centrifugal fan includes an impeller and fan inlet port. The impeller has a main plate connected to the drive shaft in a fan casing, fan side plates, and a plurality of blades between the main plate and each of the fan side plates. The fan inlet port has an opening corresponding to the inner diameter of the blades. The blades on the side of the larger pressure loss in the suction air passage to the fan inlet port have a smaller inner diameter than the blades on the side of the smaller pressure loss. This equalizes the total pressure increase in the blades along the drive shaft, resulting in a compact double inlet centrifugal fan capable of supplying the required air flow.

Abstract: A control device accommodating unit (15) is provided in a section (50) accommodating an indoor air blower (7) adjacently to an indoor air flow-in port (16), and an impeller (7c) of the indoor air blower (7) is sequentially opposite to the indoor air flow-in port (16) and the control device accommodating unit (15) by rotation of the impeller (7c), and a space (51) is formed between the indoor air flow-in port (16) and the control device accommodating unit (15). In this configuration, it is possible to obtain a cooling device decreased in drop of air flow rate and drop of cooling performance due to mounting a control device (14).

Abstract: A centrifugal blower unit comprising an impeller disposed therein and a scroll casing covering the exterior, the scroll casing having an outlet port, a tongue-like portion, a scroll portion of a volute shape and side casing plates provided with inlet ports on both sides, featuring advantages of increasing a static pressure and reducing an input power and noise while also achieving compactness in size. The scroll portion is provided with tapered scroll walls formed in anti-tongue-side wall adjacent to the outlet port by having it bent along bent lines toward the impeller and at angles to a driving shaft of the impeller such that a cross sectional area of the scroll portion in a direction of the driving shaft becomes gradually smaller toward the side casing plates.

Abstract: A blower apparatus comprises a box-like main frame provided with a main-frame inlet port and a main-frame outlet port in positions confronting each other, and a plurality of centrifugal blower units for suctioning through a blower inlet port air taken inside of the main frame from the main-frame inlet port and discharging the air from a blower air outlet toward the main-frame outlet port. The main frame is provided with a maintenance opening in one of the surfaces other than the surfaces having the main-frame inlet port and the main-frame outlet port for the purpose of checking the inside of the main frame, and the plurality of centrifugal blower units are disposed one another in a direction toward the maintenance opening so 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.

Abstract: A fan (60) with a sound deadening box has in its body (3) a double inlet centrifugal fan (9) and an inlet-port sound absorber (11) formed between the fan (9) and a body air inlet (1). The fan (60) further includes a casing-inlet-port-side air passage (26) and triangular prism shaped first inlet-port-sound-absorber air passage (27). With this structure, the fan (60) has a low pressure loss, a low input, high static pressure, and a low level of airflow collision noise.

Abstract: A double inlet centrifugal fan includes an impeller and fan inlet port. The impeller has a main plate connected to the drive shaft in a fan casing, fan side plates, and a plurality of blades between the main plate and each of the fan side plates. The fan inlet port has an opening corresponding to the inner diameter of the blades. The blades on the side of the larger pressure loss in the suction air passage to the fan inlet port have a smaller inner diameter than the blades on the side of the smaller pressure loss. This equalizes the total pressure increase in the blades along the drive shaft, resulting in a compact double inlet centrifugal fan capable of supplying the required air flow.