Harness, Dickey & Pierce, P.L.C.
Pick-up device for a microphone
 A pick-up device includes a front cover, a diaphragm incorporating a voice coil disposed posteriorly of the front cover, a front flux shield plate disposed posteriorly of the diaphragm and having a first hole, a magnet disposed at a back side of the front flux shield plate and having a second hole aligned with the first hole, a yoke disposed around the front flux shield plate and the magnet and confining a first air passage with both the front flux shield plate and the magnet, a rear flux shield plate disposed at the back sides of the magnet and the yoke and having a threaded third hole which is aligned with the second hole, the rear flux shield plate further having a second air passage which is communicated with the first air passage, an encapsulation to encompass the yoke and the rear flux shield plate, a rear cap to encompass the encapsulation and the rear flux shield plate, a screw rod passing through the rear cap and threadedly engaged with the third hole, thereby closing the third hole, and a high frequency resonance pad provided in front of the front flux shield plate and having a securing portion which extends into at least the first and second holes, the high frequency resonance pad being formed via an in-situ forming process. 
H
H04R
inventional
Ching-Lu
Chang