Microelectromechanical loudspeaker with a large-area force field

Patent metadata

Field	Value
Publication number	US-2025083948-A1
Application number	US-202418815919-A
Country	US
Kind code	A1
Filing date	Aug 27, 2024
Priority date	Sep 12, 2023
Publication date	Mar 13, 2025
Grant date	—

Abstract

A microelectromechanical loudspeaker. The loudspeaker includes a substrate, a housing arranged on the substrate, and a cavity delimited by the housing and the substrate. The loudspeaker includes a translation device, which is arranged in the cavity so as to be movable and deflectable in a specified movement direction parallel to the substrate surface and includes an arrangement of a plurality of movable fin structures, which are arranged next to one another in the movement direction and divide the cavity into a plurality of portions fluidically separated from one another, and a support structure connecting the movable fin structures to one another, and a drive device designed to deflect the translation device in the movement direction, including a plurality of drive units each including least one actuator electrode mechanically connected to the translation device and at least one stator electrode mechanically connected to the housing and/or the substrate.

First claim

1 - 16 . (canceled)

17 . A microelectromechanical loudspeaker, comprising:
a substrate with a substrate surface; a housing arranged on the substrate; a cavity delimited by the housing and the substrate; a translation device, which is arranged in the cavity so as to be movable and deflectable in a specified movement direction parallel to the substrate surface and includes an arrangement of a plurality of movable fin structures, which are arranged next to one another in the movement direction and divide the cavity into a plurality of portions fluidically separated from one another, and a support structure connecting the movable fin structures to one another; a drive device configured to to deflect the translation device in the movement direction, the device including a plurality of drive units which each include at least one actuator electrode mechanically connected to the translation device and at least one stator electrode mechanically connected to the housing and/or the substrate, wherein the actuator electrode and the stator electrode assigned to a drive unit are configured to, when they are subjected to different electrical potentials, generate an electrostatic force that accelerates the translation device in the movement direction; wherein at least some of the actuator electrodes are arranged on the support structure.

18 . The microelectromechanical loudspeaker according to claim 17 , wherein:
immovable fin structures arranged on the substrate and/or the housing are in each case provided between two directly adjacent, movable fin structures, and a gas volume that can be compressed by a movement of the movable fin structures in the movement direction is formed in each case between the movable fin structures and the immovable fin structures directly adjacent to them.

19 . The microelectromechanical loudspeaker according to claim 17 , wherein the translation device includes two translation devices moving in opposite directions and including in each case a respective movable support structure and a plurality of respective movable fin structures arranged on the respective support structure are provided in the cavity, wherein the respective movable fin structures of the two translation devices are arranged alternately in the movement direction in such a way that a gas volume that can be compressed by a relative movement of the respective fin structures is in each case formed between the respective movable fin structures of a first translation device of the two translation devices and the respective movable fin structures of a second translation device of the two translation devices.

20 . The microelectromechanical loudspeaker according to claim 17 , wherein some of the actuator electrodes are arranged on a top side and/or on a bottom side of the at least one movable fin structure.

21 . The microelectromechanical loudspeaker according to claim 17 , wherein:
the housing includes a frame structure laterally enclosing the cavity, wherein the movable support structure is configured in a shape of a frame, in which the movable fin structures are laterally clamped; at least some of the actuator electrodes are arranged on end faces of the support structure; and stator electrodes assigned to respective actuator electrodes are arranged on inner sides of the frame structure that are arranged opposite the end faces of the support structure.

22 . The microelectromechanical loudspeaker according to claim 17 , wherein:
the housing includes a frame structure laterally enclosing the cavity; the movable support structure is in ae shape of a frame, in which the movable fin structures are laterally clamped; at least some of the actuator electrodes are arranged on an outer side of side walls of the support structure; and stator electrodes assigned to respective actuator electrodes are arranged on inner sides of the frame structure that are arranged opposite the side walls of the support structure.

23 . The microelectromechanical loudspeaker according to claim 17 , wherein:
the housing includes a frame structure, which laterally encloses the cavity and in which the movable fin structures are laterally clamped; and in a central region of the moveable fin structures, the support structure interconnects the movable fin structures arranged next to one another in the movement direction.

24 . The microelectromechanical loudspeaker according to claim 17 , wherein on top and/or bottom sides of at least some of the movable fin structures on the top and/or bottom sides, the at least one of the moveable fin structures include lateral expansion structures, which extend in the movement direction and in each case includes a plurality of actuator electrodes arranged next to one another in the movement direction.

25 . The microelectromechanical loudspeaker according to claim 17 , wherein:
the actuator electrodes and stator electrodes assigned to the actuator electrodes in each case include a plurality of rail-shaped structures extending in the movement direction; the rail-shaped structures of the actuator electrodes and the rail-shaped structures of the stator electrodes interlock like a comb.

26 . The microelectromechanical loudspeaker according to claim 17 , wherein the actuator electrodes and the stator electrodes are in each case planar and are arranged opposite one another and separated from one another by a defined gap.

27 . The microelectromechanical loudspeaker according to claim 17 , wherein the actuator electrodes and the stator electrodes are in each case arranged next to one another in the movement direction and form two interlocking crenellated structures.

28 . The microelectromechanical loudspeaker according to claim 17 , wherein:
the actuator electrodes and stator electrodes assigned to the actuator elements are in each case in a form of a plurality of electrode plates, which are arranged one below the other in a direction perpendicular to the substrate surface and extend in parallel with the substrate surface; the electrode plates of the actuator electrodes and the electrode plates of the stator electrodes are arranged alternately in the direction perpendicular to the substrate plane and are in each case connected to one another via their own connection structure.

29 . The microelectromechanical loudspeaker according to claim 17 , wherein:
each of at least some of the actuator electrodes includes a two-dimensional arrangement of stamp electrodes extending in the movement direction and connected to one another via a connection structure, and stator electrodes assigned to the at least some of the actuator electrodes in each case includes an arrangement of correspondingly shaped hole electrodes, wherein each hole electrode is configured to receive the stamp electrode of the actuator electrode assigned to it.

30 . The microelectromechanical loudspeaker according to claim 29 , wherein:
the stamp electrodes in each case have a cross-sectional profile with expansions extending perpendicularly to the movement direction; and the hole electrodes assigned to the stamp electrodes have a cross-sectional profile adapted to the cross-sectional profile of the stamp electrodes.

31 . The microelectromechanical loudspeaker according to claim 30 , wherein the cross-sectional profile of the stamp electrodes is in a shape of a double-T-beam or cross.

32 . The microelectromechanical loudspeaker according to claim 17 , wherein the support structure includes a displacement support, which connects the movable fin structures of the translation device to one another, and a drive sup

Assignees

• Bosch Gmbh Robert

Inventors

• Winden Andreas
• Gehl Bernhard
• Maier Daniel
• Engelhart Peter

Classifications

• H04R2400/11

  Aspects regarding the frame of loudspeaker transducers · CPC title

• H04R9/02

  Details · CPC title

• H04R9/06 Primary

  Loudspeakers · CPC title

• H04R19/02

  Loudspeakers (H04R19/01 takes precedence) · CPC title

• H04R2201/003

  Mems transducers or their use · CPC title