Silencing Arrangement
First Claim
1. A silencing arrangement for controlling fan tone noise in a motor and fan unit in which the motor is arranged, in use, to drive rotatably the fan about a rotational axis, the silencing arrangement comprising a plurality of discrete passive silencers arranged in first and second sets having open end portions arranged to face the fan, the silencers of the first set being spaced from the silencers of the second set in an axial direction and additionally being spaced from the silencers in the second set when viewed along the axial direction.
1 Assignment
0 Petitions
Accused Products
Abstract
In an appliance, such as a cyclonic vacuum cleaner, a motor is arranged to drive an impeller fan located in a motor and fan unit. The rotation of the impeller may cause nuisance tones to be generated. A silencing arrangement is provided to control such noise and includes a plurality of discrete passive silencers in the form of tube silencers arranged in a first set and a second set. The tube silencers have open end portions arranged to face the fan and the silencers of the first set are spaced from the silencers of the second set in both axial and radial directions. This combination gives the same effect as an array of closely spaced tube silencers—however, by spacing the silencers in two directions, fluid is allowed to flow freely.
21 Citations
21 Claims
- 1. A silencing arrangement for controlling fan tone noise in a motor and fan unit in which the motor is arranged, in use, to drive rotatably the fan about a rotational axis, the silencing arrangement comprising a plurality of discrete passive silencers arranged in first and second sets having open end portions arranged to face the fan, the silencers of the first set being spaced from the silencers of the second set in an axial direction and additionally being spaced from the silencers in the second set when viewed along the axial direction.
Specification