Foster Electric has been granted a patent for a speaker device that includes a speaker unit with a magnetic circuit and diaphragm, connected to a Helmholtz resonator. The design allows for improved sound generation by utilizing specific orientations and capacities within the device. GlobalData’s report on Foster Electric gives a 360-degree view of the company including its patenting strategy. Buy the report here.

According to GlobalData’s company profile on Foster Electric, Acoustic authentication was a key innovation area identified from patents. Foster Electric's grant share as of April 2024 was 48%. Grant share is based on the ratio of number of grants to total number of patents.

Speaker device with helmholtz resonator for improved sound quality

Source: United States Patent and Trademark Office (USPTO). Credit: Foster Electric Co Ltd

The granted patent (Publication Number: US11917388B2) discloses a speaker device comprising a speaker unit with a magnetic circuit and diaphragm capable of generating sound waves by vibrating the diaphragm. The device also includes a Helmholtz resonator connected to the speaker unit, with the diaphragm having a first surface facing a sealed space and a second surface facing the resonator. The resonator features a chamber with a duct connected to it, set at a capacity smaller than the sealed space, and with the magnetic circuit located outside the chamber.

Furthermore, the patent claims detail that the Helmholtz resonator's resonance frequency is set higher than the speaker unit's operation band frequency. The sealed space can be provided by a sealed container, with the structure potentially constituting an automobile. In the case of an automobile, a portion of the duct is positioned inside the cabin, from the joint to the opening, enhancing the speaker device's functionality within the vehicle environment.

To know more about GlobalData’s detailed insights on Foster Electric, buy the report here.

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GlobalData, the leading provider of industry intelligence, provided the underlying data, research, and analysis used to produce this article.

GlobalData Patent Analytics tracks bibliographic data, legal events data, point in time patent ownerships, and backward and forward citations from global patenting offices. Textual analysis and official patent classifications are used to group patents into key thematic areas and link them to specific companies across the world’s largest industries.