Automatic turn-on and turn-off control for battery-powered headsets

• US 6,704,428 B1
• Filed: 03/06/2000
• Issued: 03/09/2004
• Est. Priority Date: 03/05/1999
• Status: Expired due to Term

• Current Assignee: The Timao Group, Inc.
• Original Assignee: Michael Wurtz
• Inventors: Wurtz, Michael
• Primary Examiner(s): Kuntz, Curtis
• Assistant Examiner(s): DABNEY, PHYLESHA LARVINIA
• Application Number:
  US09/518,917
• Time in Patent Office: 1,464 Days
• Field of Search: 381/182, 381/370-375, 381/315, 381/365, 381/312, 381/323, 381/327, 381/71.6, 381/71.7, 381/71.9, 381/71.13, 381/71.14, 381/71.19, 381/72, 381/74
• US Class Current: 381/370
• CPC Class Codes: A61F 11/145 electric, e.g. for active noise reduction
• CPC Class Codes: G10K 11/17821 characterised by the analysis of the input signals only
• CPC Class Codes: G10K 11/1783 handling or detecting of non-standard events or conditions, e.g. changing operating modes under specific operating conditions
• CPC Class Codes: G10K 11/17855 for improving speed or power requirements
• CPC Class Codes: G10K 11/17875 using an error signal without a reference signal, e.g. pure feedback
• CPC Class Codes: G10K 2210/108 Communication systems, e.g. where useful sound is kept and noise is cancelled
• CPC Class Codes: G10K 2210/1081 Earphones, e.g. for telephones, ear protectors or headsets
• CPC Class Codes: H04R 1/1041 Mechanical or electronic switches, or control elements switches in general H01H
• CPC Class Codes: H04R 1/1083 Reduction of ambient noise active noise reduction per se G10K11/175; protective devices for the ear, e.g. providing acoustic protection A61F11/06
• CPC Class Codes: H04R 2460/03 Aspects of the reduction of energy consumption in hearing devices
• CPC Class Codes: H04R 5/033 Headphones for stereophonic communication details thereof, e.g. relating to batteries, cables or control elements H04R1/10

Abstract

Some workers wear headsets to protect their hearing from loud persistent noises, such as airplane engines and construction equipment. These headsets are generally passive or active, with the active ones including ear speakers and automatic noise-reduction (ANR) circuitry to cancel or suppress certain types of loud persistent noises. One problem with active headsets, particulary those that are battery-powered, concerns battery life. Workers often take the headset off or store them without turning them off and thus wasting costly battery life. Accordingly, the inventor devised active headsets with automatic turn-on and/or turn-off circuits. One exemplary embodiment senses a condition of the headsets, for example, the light, pressure, or temperature within one earcup, and then turns the headset on or off in response to the sensed condition.

Claims

1. An ANR headset having at least two operating states and comprising:

one or more earcups;

means for sensing a condition within at least one of the earcups, with the sensed condition being an inaudible condition based on user jaw movements or blood movement within a user'"'"'s head; and

means for changing the operating state of the headset from an on state to an off state in response to a perceived absence of the condition within the one earcup for at least a predetermined amount of time.

2. The headset of claim 1, wherein the predetermined period of time is at least one minute.

5. The headset of claim 1 further including means for changing the operating state of the headset from the off state to the on state.

6. The headset of claim 1, wherein the one earcup engages the head of a user to define a volume and the means for sensing senses changes of the volume.

3. An ANR headset having at least two operating states and comprising:

one or more earcups;

means for sensing a condition within at least one of the earcups, wherein the sensed condition is an inaudible condition based on user jaw movements or blood movement and the means for sensing includes a first audio transducer within the one earcup; and

means, coupled to the means for sensing a condition within the one earcup, for changing the operating state of the headset from an on state to an off state in response to a perceived absence of the condition for at least a predetermined period of time, wherein the means for changing the operating state includes a bandpass filter, a threshold detector, a processor, and a power switch, with the bandpass filter coupled between the threshold detector and the first audio transducer and the processor coupled between the threshold detector and the power switch.

4. The headset of claim 3, wherein the means for changing the operating state of the headset changes the operating state from the on state to the off state in response to perceived absence of the condition for at least one minute.

7. An ANR headset having at least an active operating state and an inactive operating state and comprising:

one or more earcups;

an ANR microphone for sensing a condition within at least one of the earcups, with the sensed condition being an inaudible condition based on user jaw movements or blood movement within the user'"'"'s head;

a timer circuit for measuring duration of a perceived absence of the condition for at least a predetermined amount of time; and

a switch coupled to the timer circuit for switching the ANR headset from one of the active and inactive operating states to the other of the active and inactive operating states after the perceived absence for at least the predetermined amount of time.

8. The ANR headset of claim 7, wherein the timer circuit comprises:

a threshold detector; and

a microprocessor coupled to the threshold detector for operating the switch.

9. The ANR headset of claim 7, wherein the predetermined amount of time is at least one minute.

10. A method of operating an ANR headset including an audio transducer attached to an earcup for engaging the ear of a user, the method comprising:

sensing a condition within a cavity at least partly defined upon engagement of the earcup with the ear of a user, with the sensed condition being an inaudible condition based on user jaw movement or blood flow in a user'"'"'s head; and

switching at least a portion of ANR headset from an active state to an inactive state in response to a perceived absence of the condition for at least a predetermined amount of time.

11. A method of claim 10, wherein switching at least the portion of the ANR headset comprises switching in response to sensing an absence of certain frequency content from the output of an audio transducer within a cavity for an amount of time of at least one minute.

12. The method of claim 10, wherein the ANR headset includes an ANR driver within the cavity and ANR circuitry coupled to the ANR driver;

and wherein the method further comprises switching the ANR circuitry from the inactive state to the active state in response to sensing deflection of a portion of the ANR driver.

13. The method of claim 11, wherein the certain frequency content is no greater than 5 Hertz.