The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 03, 2020
Filed:
Apr. 02, 2019
Johnson Electric International Ag, Murten, CH;
Chuanjiang Guo, Shenzhen, CN;
Chuanhui Fang, Hong Kong, CN;
Mingju Chen, Shenzhen, CN;
Chikuen Au, Hong Kong, CN;
JOHNSON ELECTRIC INTERNATIONAL AG, Murten, CH;
Abstract
A muffling device applied to a ventilating fan having a scroll casing that has a bottom plate and a top plate includes a first annular muffling panel and a second annular muffling panel. The first muffling panel includes a first wall extending from an edge of the through hole in a direction away from the bottom plate and a second wall extending inward from a top end of the first wall and extending toward the bottom plate. The second muffling panel includes a third wall extending from the top plate in a direction away from the bottom plate and a fourth wall extending from a top end of the third wall. The first muffling panel, the second muffling panel, and the top plate corporately define a first noise reduction chamber. A distance from the second muffling panel to the first muffling panel is gradually increased in a radially outward direction.