Back to results
US 11,143,071 B2Granted
Hybrid acoustic silencer
AssigneeCascade Engineering, Inc.
InventorsAndrew Skestone, Michael Thomas Campbell
Life of this patent
Estimating the term…
Abstract
A hybrid acoustic silencer for a motor vehicle includes an insertion loss layer tuned for good insertion loss properties at specific frequencies and an absorption layer tuned for good absorption properties at specific frequencies. The insertion loss layer is configured to be adjacent to a sound radiating surface of the motor vehicle and the absorption layer is configured to face outward from the sound radiating surface of the motor vehicle.
Claims19
An acoustic silencer for a motor vehicle having a sound radiating surface, the acoustic silencer comprising:
- a first insertion loss layer configured to be adjacent to the sound radiating surface of the motor vehicle and comprising:
- a fiber decoupler layer having a surface density of about 0.6 to 1.3 kg/m2;
- and
- a first airflow resistant scrim attached to the fiber decoupler layer, the first airflow resistant scrim having airflow resistance about 1200 to 8000 mks rayls, measured using ASTM C522;
- and
- a second absorption layer on the first insertion loss layer and configured to face outward from the sound radiating surface of the motor vehicle, and comprising:
- a fiber absorber layer on the first airflow resistant scrim, the fiber absorber layer having a surface density of about 0.3 to 0.5 kg/m2;
- and
- a second airflow resistant scrim attached to the fiber absorber layer, the second airflow resistant scrim having an airflow resistance of about 100 to 3000 mks rayls, measured using ASTM C522;
- wherein the acoustic silencer has a normal incidence absorption coefficient, as measured using ASTM E1050, of at least approximately 0.5 in a frequency range of about 630 Hz to about 1600 Hz.
7 more elements
A motor vehicle acoustic silencer comprising:
- a first insertion loss layer comprising:
- a fiber decoupler layer having a surface density of about 0.6 to 1.3 kg/m2;
- and
- a first airflow resistant scrim attached directly to the fiber decoupler layer, the first airflow resistant scrim having airflow resistance about 1200 to 8000 mks rayls, measured using ASTM C522;
- and
- a second absorption layer on the first insertion loss layer and comprising:
- a fiber absorber layer on the first airflow resistant scrim, the fiber absorber layer having a surface density of about 0.3 to 0.5 kg/m2;
- and
- a second airflow resistant scrim attached directly to the fiber absorber layer, the second airflow resistant scrim having an airflow resistance of about 100 to 3000 mks rayls, measured using ASTM C522.
6 more elements
Dependencies are inferred from the claim text.