Piezoelectric transducer arrangement with integral terminals and housing

• US 4,240,002 A
• Filed: 04/02/1979
• Issued: 12/16/1980
• Est. Priority Date: 04/02/1979
• Status: Expired due to Term

• Current Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: McKee, John M., Tosi, Kenneth F.
• Primary Examiner(s): Budd, Mark O.
• Application Number:
  US06/026,624
• Time in Patent Office: 624 Days
• Field of Search: 310/321, 310/322, 310/324, 310/330, 310/334, 310/338, 310/340, 310/344, 310/365, 179/110 A, 340/384 E, 340/388
• US Class Current: 310/324
• CPC Class Codes: H04R 17/00 Piezoelectric transducers; Electrostrictive transducers piezoelectric or electrostrictive elements in general H10N30/00; details of piezoelectric or electrostrictive motors, generators or positioners H10N30/00

Abstract

A miniature piezoelectric element is conductively mounted on a metal diaphragm having one or two projecting tabs which provide two solderless terminals. An insulating area is screened onto the diaphragm around the piezoelectric element and out onto one tab. A conductive layer is formed on the upper surface of the active element and out onto the insulating area on the tab without contacting the diaphragm. The diaphragm can then be supported within any suitable housing with the tab or tabs projecting for contact by a miniature connector.

Claims

1. A transducer device as for a miniature radio apparatus and comprising:

a planar metal diaphragm having at least one peripherally projecting portion;

a planar electromechanical element having a surface area less than the surface area of said diaphragm and having electrodes formed on the opposing faces of said element;

non-insulating mounting means for affixing a first face of the electromechanical element centrally of the diaphragm;

a thin insulating layer formed on the diaphragm and adjacent at least a portion of the electromechanical element and extending onto one projecting portion of the diaphragm;

conductive means formed on at least a portion of a second face of the electromechanical element and on a portion of the insulating layer including the insulated area on the projecting portion of the diaphragm but not in electrical contact with the diaphragm, whereby the exposed projecting portion of the diaphragm and the conductive means formed on the projecting portion provide terminals for the device; and

housing means for peripherally holding and retaining the diaphragm, having a sound aperture adjacent the second face of the electromechanical element, and having a second aperture for allowing the peripherally projecting portion of the diaphragm, including the extended portion of the insulating layer and the conductive means, to extend beyond the housing means.

2. A transducer device in accordance with claim 1 and wherein the diaphragm includes two peripherally projecting portions and the terminals for the transducer device are the second projecting portion and the conductive means formed on the first projecting portion of the diaphragm respectively.

3. A transducer device in accordance with claim 1 wherein the electromechanical element is of a ceramic material which can be made piezoelectrically active by the appropriate application of a voltage.

4. A transducer device in accordance with claim 1 wherein the non-insulating mounting means is a non-conductive epoxy cured under heat and pressure to allow electrical conduction between the electromechanical element and the diaphragm while maintaining permanent mechanical connection.