Middle ear transducer

• US 6,005,955 A
• Filed: 08/07/1996
• Issued: 12/21/1999
• Est. Priority Date: 08/07/1996
• Status: Expired due to Term

• Current Assignee: Envoy Medical Corporation (Envoy Medical, Inc.), Saint Croix Medical, Inc.
• Original Assignee: St Croix Medical Incorporated
• Inventors: Kroll, Kai, Adams, Theodore P., Meyerson, Scott C., Brillhart, Bruce A.
• Primary Examiner(s): Harvey, Minsun Oh
• Application Number:
  US08/693,436
• Time in Patent Office: 1,231 Days
• Field of Search: 381/312, 381/322, 381/324, 381/328, 600/25
• US Class Current: 381/328
• CPC Class Codes: A61F 2002/183 Ear parts
• CPC Class Codes: H04R 25/606 acting directly on the eardrum, the ossicles or the skull, e.g. mastoid, tooth, maxillary or mandibular bone, or mechanically stimulating the cochlea, e.g. at the oval window

Abstract

An electromechanical transducer for an implantable hearing aid, such as a partial middle ear implantable (P-MEI) or total middle ear implantable (T-MEI) hearing aid system. The invention comprises at least one piezoelectric element proportioned for mechanically coupling to a middle ear only through an auditory element in the middle ear, such as the tympanic membrane, malleus, incus, stapes, or in the inner ear, such as the oval window, round window, vestibule, or semicircular canals. The invention need not be secured to a temporal bone. Inertial masses and a carrier are optionally provided to assist in sensing or producing mechanical vibrations. The carrier is optionally hermetically sealed. Superpositioned individual frequency responses optimize an overall frequency bandwidth.

Claims

1. An electromechanical transducer for an implantable hearing aid, the transducer comprising:

a carrier proportioned for mechanically coupling to a middle ear only through an auditory element in the middle ear;

a first piezoelectric element mechanically coupled to the carrier for transducing between a mechanical vibration of the carrier and a first electrical signal;

a second piezoelectric element mechanically coupled to the carrier for transducing between the mechanical vibration of the carrier and a second electrical signal;

a first inertial mass mechanically coupled to the first piezoelectric element; and

a second inertial mass mechanically coupled to the second piezoelectric element.

2. The transducer of claim 1, in which the first and second inertial masses have substantially nonidentical masses.

3. The transducer of claim 2, in which the mechanical vibration of the carrier is at least partially produced by a superposition of vibrations from each of a first and second combination, the first combination including the first inertial mass and the first piezoelectric element and having a substantially nonidentical electromechanical frequency response from the second combination, the second combination including the second inertial mass and the second piezoelectric element.

4. The transducer of claim 2, in which the respective first and second electrical signals are transduced from the mechanical vibration of the carrier.

5. An implantable electromechanical device adapted for coupling exclusively only to an auditory element in a human ear for which auditory sound vibrations are transduced, the device comprising:

first and second bi-element transducers with a first inertial mass attached to said first transducer and a second inertial mass attached to said second transducer;

means for securely attaching said first and second transducers to the auditory element; and

an electronics unit to transmit electrical signals to said first and second transducers,

said electrical signals being sufficient to induce deflections forming vibratory displacements in an orientation relative to a desired directional plane within said first and second piezoelectric elements and said deflections being opposed by a resistance from each of said first and second inertial masses to thereby provide a vibratory frequency response preconditioned to exert a specific resultant vibratory force on the auditory element.

6. The device of claim 5, wherein said first and second inertial masses are substantially different masses to enable different frequency responses in combination with vibratory displacements of said first and second transducers.

7. The device of claim 6, wherein said first and second bi-element transducers are structured to vibrate with substantially nonidentical frequency responses.