To silence a sound by resonance up to an NZ frequency sound of a low frequency area, without reducing air blowing performance, in response to the NZ frequency sound generated by a fan of an air-conditioning outdoor unit.
This air-conditioning outdoor unit is formed by including an axial fan 3 concentrically arranged in a shroud 4-1 and rotating at a constant speed by being driven by a DC motor 2, a heat exchanger 5 arranged on the upstream side of an air flow passing through this axial fan 3 and exchanging heat with the air flow, a shroud cover 4-2 extendedly arranged over the downstream side on the outside of the shroud 4-1 and forming a delivery air flow passage of the axial fan, and a casing 1 for storing these members; and has a cavity part composed of a box body 8 shielded and surrounded by a back face of the shroud cover 4-2 and the casing 1; and has an opening hole 13 communicating with the delivery air flow passage with respective divisions by partitioning the inside of the cavity part into a plurality of divisions respectively different in the volume by a partition wall parallel to the axis of the axial fan 3.
| WO/2023/187451 | MOTOR COOLING SHROUD FOR A FULLY REVERSIBLE TURBOMACHINE |
| JPH11303787 | CIRCULATING PUMP |
| JP5044218 | Airflow bundle director system for X-ray tubes |
YONEYAMA HIROYASU
KISHITANI TETSUSHI
NAGAHASHI KATSUAKI
OHARA HIDEJI
KO HAKUEI
| JPS5782665A | 1982-05-24 | |||
| JP2003343489A | 2003-12-03 | |||
| JPH09228993A | 1997-09-02 | |||
| JPH10227299A | 1998-08-25 | |||
| JPH01240799A | 1989-09-26 | |||
| JPS6448000A | 1989-02-22 | |||
| JPS55161099U | 1980-11-19 |
Next Patent: OIL LEVEL GAUGE DEVICE OF ENGINE