Mass-loaded cantilever vibrator

• US 5,245,245 A
• Filed: 05/04/1992
• Issued: 09/14/1993
• Est. Priority Date: 05/04/1992
• Status: Expired due to Term

• Current Assignee: Motorola Mobility, Inc. (Lenovo Group Ltd.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Goldenberg, Michael P.
• Primary Examiner(s): Budd, Mark O.
• Application Number:
  US07/878,348
• Time in Patent Office: 498 Days
• Field of Search: 310/311, 310/312, 310/321, 310/323, 310/330-332, 340/311.1, 340/825.44, 340/146.2, 455/34, 455/38, 455/228, 455/343, 375/58
• US Class Current: 310/330
• CPC Class Codes: G08B 3/1041 with alternative alert, e.g. remote or silent alert
• CPC Class Codes: H10N 30/2042 Cantilevers, i.e. having one fixed end

Abstract

An electronic device (100) includes a housing (222) and a piezo-bender (400). The piezo-bender (400) includes a metal beam (402) having at least a portion of a surface mechanically coupled to a piezo-ceramic layer (304). The piezo-bender (400) is flexibly coupled to the housing (222) at an end of the metal beam (402) forming a cantilever structure. A vibratable body (404) is mechanically coupled to the other end of the metal beam (402). A tuning slide (604) is slidably coupled to the piezo-bender (400) for mechanically tuning the resonant frequency of vibration of the piezo-bender (400) by varying the length of the piezo-bender (400) that can vibrate. An electrical drive circuit (708) is electrically coupled to the piezo-bender (400) for electrically driving the piezo-bender (400) with a drive signal to generate vibratory motion in the piezo-bender (400) for providing a vibratory alert.

Claims

1. An electronic device capable of providing a vibratory alert, comprising:

a housing;

a piezo-bender including a metal beam having at least a portion of a surface mechanically coupled to a piezo-ceramic layer, the piezo-bender being flexibly coupled to the housing at an end of the metal beam forming a cantilever structure, and a vibratable body mechanically coupled to the other end of the metal beam;

a tuning means slidably coupled to the piezo-bender for mechanically tuning the resonant frequency of vibration of the piezo-bender by varying the length of the piezo-bender that can vibrate; and

an electrical drive circuit electrically coupled to the piezo-bender for electrically driving the piezo-bender with a drive signal to generate vibratory motion in the piezo-bender for providing a vibratory alert.

2. A selective call receiver, comprising:

`a housing;

a circuit supporting substrate within the housing and mechanically coupled thereto;

electronic circuitry disposed on the circuit supporting substrate, the electronic circuitry including;

receiving means for receiving a message comprising an address;

decoding means coupled to the receiving means for decoding the received message, and for determining if the received address matches a predetermined address; and

alert generating means coupled to the decoding means for electrically generating an alert signal if the received address matches the predetermined address; and

vibratory alert means for providing a vibratory alert in response to the alert signal, the vibratory alert means comprising;

a piezo-bender including a metal beam having at least a portion of a surface mechanically coupled to a piezo-ceramic layer, the piezo-bender being flexibly coupled to the housing at an end of the metal beam forming a cantilever structure, and a vibratable body mechanically coupled to the other end of the metal beam, and being electrically coupled to the alert generating means and responsive to the alert signal for electrically driving the piezo-bender with the alert signal to generate vibratory motion in the piezo-bender for providing a vibratory alert; and

a tuning slide slidably coupled to the piezo-bender for mechanically tuning the resonant frequency of vibration of the piezo-bender by varying the length of the piezo-bender that can vibrate.

3. The selective call receiver of claim 2, wherein the alert signal for electrically driving the piezo-bender comprises a frequency in the range below 300 Hz for vibrating the piezo-bender to provide a tactile alert.