Abstract: The invention relates to an electromagnetic actuator, which is designed to be connected to a backside of a plate like structure and which comprises an annular coil arrangement and a magnet system being designed to generate a magnetic field transverse to the annular coil arrangement. The annular coil arrangement and the magnet system are connected to each other by a plurality of springs, which are arranged inside of the annular coil arrangement.

Abstract: The invention relates to an electromagnetic actuator, which is designed to be connected to a backside of a plate like structure and which comprises an annular coil arrangement and a magnet system being designed to generate a magnetic field transverse to the annular coil arrangement. The annular coil arrangement and the magnet system are connected to each other by a plurality of springs, which are arranged inside of the annular coil arrangement. Furthermore, the invention relates to an output device, comprising a plate like structure and an electromagnetic actuator of the above kind connected to a backside of the plate like structure.

Abstract: An electrodynamic actuator (1a, 1b) is disclosed, which is designed to be connected to a plate like structure (2) and which comprises a coil arrangement (3a, 3b) with at least one voice coil (4a, 4b), a magnet system (5) with a movable magnetic circuit part (7, 7a . . . 7f) and a static magnetic circuit part (6a . . . 6F) and a spring arrangement (12) coupling the static magnetic circuit part (6a . . . 6F) to the movable magnetic circuit part (7, 7a . . . 7f) and allowing a relative movement between the same. Both the spring arrangement (12) and the magnet system (5) provide a total restoring force (FT) directed towards an idle position (P0) of the movable magnetic circuit part (7, 7a . . . 7f). A part of a total restoring force gradient (?FT/?z) caused by the magnet system (5) is at least 10% of the total restoring force gradient (?FT/?z) in said idle position (P0) of the movable magnetic circuit part (7, 7a . . . 7f).

Abstract: An electrodynamic actuator (1a, 1b) is disclosed, which is designed to be connected to a plate like structure (2) and which comprises a coil arrangement (3a, 3b) with at least one voice coil (4a, 4b), a magnet system (5) with a movable magnetic circuit part (7, 7a . . . 7f) and a static magnetic circuit part (6a . . . 6F) and a spring arrangement (12) coupling the static magnetic circuit part (6a . . . 6F) to the movable magnetic circuit part (7, 7a . . . 7f) and allowing a relative movement between the same. Both the spring arrangement (12) and the magnet system (5) provide a total restoring force (FT) directed towards an idle position (P0) of the movable magnetic circuit part (7, 7a . . . 7f). A part of a total restoring force gradient (?FT/?z) caused by the magnet system (5) is at least 10% of the total restoring force gradient (?FT/?z) in said idle position (P0) of the movable magnetic circuit part (7, 7a . . . 7f).

Abstract: The invention relates to an electromagnetic actuator, which can be connected to a backside of a plate like structure and which comprises a voice coil, a magnet system and a spring arrangement connecting the voice coil and a movable part of the magnet system. The spring arrangement comprises at least two spiral springs each having at least three spring legs. The spring legs run in radial and tangential direction in a clockwise or counterclockwise winding direction and are rotational symmetric around the coil axis. The winding directions of the spiral springs are chosen in a way that rotations around the coil axis caused by a relative movement between the voice coil and the movable part of the magnet system in the excursion direction are oriented in opposite directions. The invention also relates to an output device with a plate like structure and an electromagnetic actuator connected thereto.

Abstract: The invention relates to an electromagnetic actuator, which can be connected to a backside of a plate like structure and which comprises a voice coil, a magnet system and a spring arrangement connecting the voice coil and a movable part of the magnet system. The spring arrangement comprises at least two spiral springs each having at least three spring legs. The spring legs run in radial and tangential direction in a clockwise or counterclockwise winding direction and are rotational symmetric around the coil axis. The winding directions of the spiral springs are chosen in a way that rotations around the coil axis caused by a relative movement between the voice coil and the movable part of the magnet system in the excursion direction are oriented in opposite directions. The invention also relates to an output device with a plate like structure and an electromagnetic actuator connected thereto.

Abstract: The invention relates to an electromagnetic actuator, which is designed to be connected to a backside of a plate like structure and which comprises an annular coil arrangement and a magnet system being designed to generate a magnetic field transverse to the annular coil arrangement. The annular coil arrangement and the magnet system are connected to each other by a plurality of springs, which are arranged inside of the annular coil arrangement. Furthermore, the invention relates to an output device, comprising a plate like structure and an electromagnetic actuator of the above kind connected to a backside of the plate like structure.

Abstract: An open modular speaker assembly is configured to be inserted into a mobile wireless device and includes a frame, a magnetic assembly that is disposed within the frame and a membrane assembly disposed within the frame and in proximity to the magnetic assembly. Actuation of the magnetic assembly by an electric current causes a movement of the magnetic assembly causing a resultant movement of the membrane assembly. A first portion of the mobile wireless device and the membrane assembly form a front volume where the resultant movement of the membrane assembly produces sound in the front volume, and such that a second portion of the mobile wireless device and the membrane assembly form a back volume that is separated from the front volume by the membrane assembly. Air is displaced or exchanged between the front volume and the back volume.