Patent US4684853A successfully refreshed from Google Patents.
US4684853A
Expired / Lapsed
US
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Garage door opener using transmitter with SAW oscillator modulator
Assignee: Emhart Industries Inc
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Filing: 1986-07-25
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Granted: 1987-08-04
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Expires: 2006-07-25
Abstract
Abstract A radio frequency (r-f) transmitter has an electric oscillator circuit for producing an oscillating r-f signal in an antenna. A feedback sub-circuit of the oscillator circuit includes a surface acoustic wave (SAW) resonator for stabilizing the oscillations. The feedback circuit has a Q of less than 12000. There is a modulation sub-circuit of the oscillator circuit which includes a voltage variable capacitor. The voltage variable capacitor responds to input voltage variations to modulate the capacitance of the feedback circuit, thereby modulating the frequency of the transmitter. A garage door opener system employing the transmitter is also disclosed.
Inventors
- 👤 Ronald J. Coash
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 13:25
CPC Classifications
H; H03; H03B; H03B5/00; H03B5/30; H03B5/32; H03B5/326; E; E05; E05F; E05F15/00; E05F15/70; E05F15/77; G; G07; G07C; G07C9/00; G07C9/00174; G07C9/00182; E05Y; E05Y2900/00; E05Y2900/10; E05Y2900/106; G07C2009/00753; G07C2009/00769; G07C2009/00793; G07C9/00896; G07C2009/00928
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
127 words
A garage door opener system comprising: a means for mechanically connecting to a garage door; a motor for driving said means for connecting; a manually operable switch; means responsive to said switch for producing a transmitter input signal, a transmitter responsive to said transmitter input signal for producing an r-f outout signal, said transmitter comprising an electric oscillator circuit means for producing said r-f output signal, a surface acoustic wave device connected within said oscillator circuit means for stabilizing oscillations of said r-f output signal, and means for modulating the oscillation frequency of said oscillator circuit means; a receiver for receiving said r-f output signal and for producing a controller input signal; a controller means responsive to said controller input signal for providing power to said motor.
Claim 2
Dependent Claim
127 words
A garage door opener system comprising: a means for mechanically connecting to a garage door; a motor for driving said means for connecting; a manually operable switch; means responsive to said switch for producing a transmitter input signal, a transmitter responsive to said transmitter input signal for producing an r-f outout signal, said transmitter comprising an electric oscillator circuit means for producing said r-f output signal, a surface acoustic wave device connected within said oscillator circuit means for stabilizing oscillations of said r-f output signal, and means for modulating the oscillation frequency of said oscillator circuit means; a receiver for receiving said r-f output signal and for producing a controller input signal; a controller means responsive to said controller input signal for providing power to said motor.
Claim 3
Dependent Claim
46 words
The garage door opener of claim 1 wherein said oscillator circuit means includes a feedback circuit and said surface acoustic wave device is a surface acoustic wave resonator electrically connected within said feedback circuit to stabilize the oscillation of said oscillator circuit means about prescribed frequency.
Claim 4
Dependent Claim
18 words
The garage door opener of claim 2 wherein the Q of said feedback circuit is less than 12,000.
Claim 5
Dependent Claim
24 words
The garage door opener of claim 1 wherein said means for modulating comprises a means for modulating the capacitance of said oscillator circuit means.
Claim 6
Dependent Claim
19 words
The garage door opener of claim 4 wherein said means for modulating the capacitance comprises a voltage variable capacitor.
Claim 7
Dependent Claim
61 words
The garage door opener of claim 1 and further including input means for producing an input signal having a series of voltage transitions between a high voltage value and a low voltage value, and wherein said means for modulating modulates the oscillation frequency of said oscillator circuit means to produce an r-f signal having frequency shifts corresponding to said voltage transitions.
Claim 8
Dependent Claim
16 words
The garage door opener of claim 6 wherein said input signal comprises a Manchester encoded signal.
Claim 9
Dependent Claim
21 words
The garage door opener of claim 6 wherein said oscillation frequency is in a range between 50 megahertz and one gigahertz.
Claim 10
Dependent Claim
20 words
The garage door opener circuit of claim 8 wherein said frequency shift is equal to or greater than 60 kilohertz.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-08-03 | 1991-02-02 | 1991-08-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-08-03 | 1995-02-02 | 1995-08-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-08-03 | 1999-02-02 | 1999-08-04 | $7700.00 | Window Closed / Lapsed |