Unlock instant, AI-driven research and patent intelligence for your innovation.

Acoustic actuators

An acoustic transducer, driven technology, used in magnetostrictive sensors, transducers, piezoelectric/electrostrictive transducers, etc.

Inactive Publication Date: 2010-12-15
费奥尼克有限公司
View PDF5 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

It has been found through experimentation and experimentation that, especially when miniaturized, the output sound signal produced by such a device is deformed by the ring spring, causing unpredictable stretching of the driven surface, resulting in deviations that destroy the audio output ( off square) output force

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Acoustic actuators
  • Acoustic actuators
  • Acoustic actuators

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0032] Referring first to Figure 1, the active element 11 is mounted substantially horizontally on an inertial or back mass 10 which is attached to a base 14 by means of a resilient plate 15 which acts as a solid state hinge. The support plate 16 extends perpendicularly to the hinge and engages the support curved surface 12 mounted on the end of the active element 11 . A leaf spring 13 is arranged between the support plate 16 and the back mass 10 in order to apply a controlled pretension to the active elements. The active element is thus driven horizontally, and the actuator converts this movement into a vertical force through a hinge, preferably a solid state hinge, to reduce energy loss. Hinges with pins and / or bearing surfaces produce undesired losses due to movements involving small amplitudes. The support curve 12 may be part of the element, or more advantageously a separate piece of low compliance material.

[0033] In the case of magnetostrictive active elements, for ...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

An acoustic transducer comprises an active element (21) which changes in length along a first axis in response to an audiofrequency input signal, the element being mounted between an inertial mass (20) and a foot (24) which in use engages a surface whereby audiofrequency vibrations produced by the active element are transmitted to the surface, characterised in that the foot is hingedly (25) connected to the inertial mass and the active element is located between the foot and the mass such that the angle between the first axis and the surface is less than 90 DEG , in use. Acoustic actuators with a magnetostrictive element having two statched coils, or with two magnetostrictive elements, the coils or elements having mutually different frequency response to achieve broader bandwidth are alsodisclosed.

Description

technical field [0001] The present invention relates to acoustic actuators, such as the type used to drive flat-panel sound generators. Background technique [0002] Direct drive actuators using active elements which are rods of magnetostrictive material are well known. An example of such an actuator is disclosed and claimed in our published international application WO 02 / 076141. The way these actuators are constructed means that although they provide high forces, their physical profile is not suitable for some applications. Other active elements such as piezoelectric elements can be incorporated into actuators that have a planar or narrow profile and are suitable for many applications where magnetostrictive actuators are not. But piezoelectric actuators provide less force, require high voltages around 100v, and are not suitable for acoustic applications with frequencies below 1KHz. For these reasons piezoelectric actuators cannot be used. While laminated piezoelectric ...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Patents(China)
IPC IPC(8): H04R15/00H04R17/00H04R7/04H04R1/24H04R1/26H04R1/00
Inventor W·J·梅特林汉姆D·A·约翰逊B·D·史密斯N·芒斯M·G·阿斯顿
Owner 费奥尼克有限公司