Telefonaktiebolaget Lm Ericsson (Publ)

Sony Ericsson Mobile Communications Ab

Anders Edgren

Magnus F Hansson

Mohammad Vatankhah

Patrik Bergman

Carl Henrik Tullstedt

The present invention relates to an electro-acoustic communications unit () and a portable communication device () for producing a desired frequency characteristics in alert mode and phone mode, comprising a housing with a wall () defining an interior, having a certain volume and an exterior of the housing, an acoustic driver () for generating acoustic signals, said acoustic driver () being mounted to the wall (), an acoustic port (), having a length and a cross-sectional area, said port () penetrating the wall () and connecting the interior of the housing with the exterior of said housing, where the volume, length and cross-sectional area are dimensioned in relation to the acoustic driver () in a way such that said electro-acoustic communications unit achieves a desired frequency characteristics when engaging the exterior end () of said acoustic port of the communications unit with a user's ear ().

Electro-acoustic transducer for a portable communication device

In a method of controlling a vibrator, the vibrator is first driven towards a first frequency during a first interval and then is driven towards a second frequency during a second interval. In a preferred embodiment the first frequency is higher than the lowest resonance frequency of the vibrator and the vibrator is then allowed to reduce the frequency to a frequency lower than the resonance frequency. By letting the frequency vary in a pulsating manner in the vibrating device, the vibration can be sensed more easily by a human, and thereby making it possible to use a very small mass in the vibrating device, which therefore can be made using a small weight, while still making it possible to sense the vibration.

Vibrator

A device for increasing heat transfer from an object includes at least one oscillating membrane for generating air motion in air surrounding the object, and a nozzle for affecting the air motion so that the air motion causes a continuous exchange of the air surrounding the object.

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Stockholm, Sweden

Anders Edgren