Patent · US Expired

Acoustic-device cooling unit

US4860361A · kind A · utility

40Cited by
2References
4Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 2, 1988
Grant dateAug 22, 1989
Priority date
Expiry dateSep 2, 2008

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03F1/52
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

A cooling unit for cooling an acoustic device installed on the vehicle by using a cooling fan comprises a cooling fan drive circuit which outputs a DC voltage proportional to the input or output signal level of the acoustic device to control the speed of rotation of the cooling fan motor, whereby the noise of the cooling fan is suppressed in a sense of hearing when no signal is provided by the acoustic device.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.