US4860361A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Acoustic-device cooling unit
Assignee: Pioneer Corp
•
Filing: 1988-09-02
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Granted: 1989-08-22
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Expires: 2008-09-02
Abstract
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.
Inventors
- 👤 Takeshi Sato
- 👤 Hiroo Adachi
- 👤 Shigeru Munetomo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 16:34
CPC Classifications
H; H03; H03F; H03F1/00; H03F1/52
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
55 words
A cooling unit for cooling an acoustic device with a cooling fan, which comprises: a cooling fan drive circuit for outputting a DC voltage corresponding to an input or output signal level of said acoustic device; and a cooling fan motor which is driven by the DC voltage provided by said cooling fan drive circuit.
Claim 2
Dependent Claim
55 words
A cooling unit for cooling an acoustic device with a cooling fan, which comprises: a cooling fan drive circuit for outputting a DC voltage corresponding to an input or output signal level of said acoustic device; and a cooling fan motor which is driven by the DC voltage provided by said cooling fan drive circuit.
Claim 3
Dependent Claim
29 words
A cooling unit as claimed in claim 1, in which said cooling fan drive circuit outputs a DC voltage corresponding to an input signal level of said acoustic device.
Claim 4
Dependent Claim
51 words
A cooling unit as claimed in claim 2, in which said cooling fan drive circuit comprises: an amplifier for amplifying part of an input signal of said acoustic device; a rectifier circuit for rectifying an output of said amplifier; and a smoothing circuit for smoothing an output of said rectifier circuit.
Claim 5
Dependent Claim
43 words
A cooling unit as claimed in claim 3, in which said cooling fan drive circuit further comprises; a DC voltage source; and an addition circuit for adding the output DC voltage of said DC voltage source to an output of said smoothing circuit.
References Cited (Backward Citations)
US3195034A
Cited
US4267500A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-08-21 | 1993-02-20 | 1993-08-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-08-21 | 1997-02-20 | 1997-08-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-08-21 | 2001-02-20 | 2001-08-22 | $7700.00 | Window Closed / Lapsed |