Sensed sound level based fan speed adjustment

Patent metadata

Field	Value
Publication number	US-9311909-B2
Application number	US-201213631308-A
Country	US
Kind code	B2
Filing date	Sep 28, 2012
Priority date	Sep 28, 2012
Publication date	Apr 12, 2016
Grant date	Apr 12, 2016

Abstract

Sounds sensed by a microphone of a device include sounds from a cooling fan of the device that varies based on the speed of the cooling fan, and other sounds used by a program of the device such as voice inputs. The sound level of sounds used by the program is determined, and the speed of the fan is adjusted so that a desired cooling level is attained while keeping the fan speed low enough that the noise from the fan does not interfere with the sounds used by the program.

First claim

What is claimed is:

1. A method implemented in a device, the method comprising:
detecting a sound level of sounds sensed by a microphone, the sounds including a particular range of frequencies used by a program of the device, and the program receiving audio inputs in the particular range of frequencies via the microphone;
determining a sound level of a fan of the device at a current fan speed, the determining comprising using a speed to noise transfer function to identify the sound level generated by the fan of the device at the current fan speed; and
adjusting a speed of the fan so that the sound level of the fan is less than a sound level sensed by the microphone that is attributable to sounds other than fan noise.

2. A method as recited in claim 1 , the adjusting further comprising adjusting the speed of the fan to run at at least a threshold speed to provide a desired amount of cooling regardless of the sound level of the fan.

3. A method as recited in claim 1 , the adjusting further comprising reducing how quickly the speed of the fan is adjusted in response to changes in sound level of the fan.

4. A method as recited in claim 3 , the reducing how quickly the speed of the fan is adjusted in response to changes in sound level of the fan comprising averaging the current fan speed over an amount of time.

5. A method as recited in claim 3 , the reducing how quickly the speed of the fan is adjusted in response to changes in sound level of the fan comprising averaging an indication of the sound level of the fan over an amount of time.

6. A method as recited in claim 3 , the reducing how quickly the speed of the fan is adjusted in response to changes in sound level of the fan comprising averaging a value of a control signal indicating a voltage to apply to a motor of the fan over an amount of time.

7. A method as recited in claim 1 , the program comprising a program to record voices at the device, the particular range of frequencies comprising frequencies that are recorded by the program.

8. A method as recited in claim 1 , the program comprising a video conferencing program that transmits voices to an additional device, the particular range of frequencies comprising frequencies that are transmitted to the additional device.

9. A method as recited in claim 1 , further comprising playing back, via one or more speakers of the device, a sound wave that cancels at least part of the sound level of the fan.

10. A method as recited in claim 1 , the speed to noise transfer function being determined for only the particular range of frequencies used by the program.

11. A method as recited in claim 1 , the determining further comprising selecting one of multiple different speed to noise transfer functions to identify the sound level of the fan of the device at the current fan speed, each of the multiple different speed to noise transfer functions being associated with a different one of multiple microphones of the device, the selecting comprising selecting the speed to noise transfer function associated with an activated one of the multiple microphones.

12. A method as recited in claim 1 , the microphone comprising one of multiple microphones of the device that is sensing a highest sound level, lowest sound level, or averaged sound level of the multiple microphones.

13. The method as recited in claim 1 , further comprising:
determining a second sound level of a second fan of the device at a second current fan speed; and
adjusting a speed of the second fan so that the sound level of both of the fans is less than the sound level sensed by the microphone that is attributable to sounds other than fan noise.

14. A system in a device, the system comprising:
a microphone that detects sounds in a particular range of frequencies used by a program of the device;
a fan motor that controls, based on an input voltage, a speed of a fan of the device; and
a difference logic coupled to receive audio data including sounds sensed by the microphone in the particular range of frequencies, the difference logic being configured to determine, based on both a sound level of the sounds sensed by the microphone and a sound level generated by the fan of the device at a current fan speed, a voltage to apply to the fan motor so that a sound level of the fan is less than a sound level sensed by the microphone of sounds other than fan noise, the difference logic being configured to determine the voltage to apply to the fan motor based on a speed to noise transfer function that identifies the sound level generated by the fan of the device at the current fan speed.

15. A system as recited in claim 14 , the system further including a threshold cooling voltage to apply to the fan motor so that the speed of the fan provides a desired amount of cooling regardless of the voltage determined by the difference logic.

16. A system as recited in claim 14 , the system further including a filter that reduces how quickly the voltage to apply to the fan motor is adjusted in response to changes in the sound level of the fan and/or the sound level of the sounds detected by the microphone.

17. A system as recited in claim 16 , the filter being configured to average the current fan speed over an amount of time.

18. A system as recited in claim 14 , the speed to noise transfer function identifying the sound level of the fan at various speeds.

19. A system as recited in claim 18 , the speed to noise transfer function being determined for only the particular range of frequencies used by the program.

20. A method implemented in a device, the method comprising:
detecting a sound level of sounds sensed by a microphone, the sounds including a particular range of frequencies used by a program of the device, and the program receiving audio inputs in the particular range of frequencies via the microphone;
determining a sound level of a fan of the device at a current fan speed, the determining including using a speed to noise transfer function to identify the sound level generated by the fan of the device at the current fan speed in the particular range of frequencies used by the program, the determining further including selecting one of multiple different speed to noise transfer functions to identify the sound level of the fan of the device at the current fan speed, each of the multiple different speed to noise transfer functions being associated with a different one of multiple microphones of the device, the selecting comprising selecting the speed to noise transfer function associated with an activated one of the multiple microphones; and
adjusting a speed of the fan so that the sound level of the fan is less than a sound level sensed by the microphone that is attributable to sounds other than fan noise, and reducing how quickly the speed of the fan is adjusted by averaging the current fan speed over an amount of time.

21. A device comprising:
a microphone configured to detect sounds in a particular range of frequencies;
a fan motor configured to control, based on an input voltage, a speed of a fan; and
a circuit configured to receive audio data including sounds sensed by the microphone in the particular range of frequencies, the circuit being configured to determine, based on both a sound level of the sounds sensed by the microphone and a sound level generated by the fan at a current fan speed, a voltage to apply to the fan motor so that a sound level of the fan is less than a sound level sensed by the microphone of sounds other than fan noise, and based on a spee

Assignees

• Microsoft Technology Licensing Llc

Inventors

• Giaimo Iii Edward C
• He Yi
• Evans Duane Martin
• Delano Andrew D

Classifications

• H04R3/02

  for preventing acoustic reaction {, i.e. acoustic oscillatory feedback (specially adapted for hearing aids H04R25/453)} · CPC title

• F01P11/12

  Filtering, cooling, or silencing cooling-air · CPC title

• H04R27/00

  Public address systems (circuits for preventing acoustic reaction H04R3/02; circuits for distributing signals to loudspeakers H04R3/12; {monitoring or testing arrangements for public address systems H04R29/007}; amplifiers H03F) · CPC title

• G10K11/16 Primary

  Methods or devices for protecting against, or for damping, noise or other acoustic waves in general (G10K11/36 takes precedence) · CPC title

• H04R2227/003

  Digital PA systems using, e.g. LAN or internet · CPC title