US3716865A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Radio controlled system for garage door opener
Assignee: Chamberlain Manufacturing Corp
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Filing: 1971-06-10
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Granted: 1973-02-13
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Expires: 1991-06-10
Abstract
Abstract A closure operator including a simultaneously and synchronously pulsed and frequency modulated transmitter for use in conjunction with a remote receiver for controlling a closure operator and in which the range of control is substantially increased over prior art transmitters. By frequency modulating the pulse output of the transmitter, more energy will be received by the receiver without exceeding the radiation limits as established by the Federal Communications Commission thus allowing greater range. The circuit also utilizes a split stator type tuning capacitor in the transmitter which provides for a relatively constant frequency deviation component over a wide RF carrier tuning range.
Inventors
- 👤 C Willmott
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 15:27
CPC Classifications
G; G08; G08C; G08C19/00; G08C19/16; G08C19/26; E; E05; E05F; E05F15/00; E05F15/70; E05F15/77; E05Y; E05Y2900/00; E05Y2900/10; E05Y2900/106
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
85 words
A transmitter for remote control comprising: a carrier frequency oscillator which includes a frequency contRolling circuit; a tone oscillator connected to said carrier frequency oscillator to key it on and off at the tone frequency; an FM modulator; a voltage variable capacitor forming a part of said FM modulator and said voltage variable capacitor connected to said frequency controlling circuit of said carrier frequency oscillator; and an integrating circuit receiving an input from said tone oscillator and supplying an output to said voltage variable capacitor.
Claim 2
Dependent Claim
85 words
A transmitter for remote control comprising: a carrier frequency oscillator which includes a frequency contRolling circuit; a tone oscillator connected to said carrier frequency oscillator to key it on and off at the tone frequency; an FM modulator; a voltage variable capacitor forming a part of said FM modulator and said voltage variable capacitor connected to said frequency controlling circuit of said carrier frequency oscillator; and an integrating circuit receiving an input from said tone oscillator and supplying an output to said voltage variable capacitor.
Claim 3
Dependent Claim
85 words
A transmitter for remote control comprising: a carrier frequency oscillator which includes a frequency contRolling circuit; a tone oscillator connected to said carrier frequency oscillator to key it on and off at the tone frequency; an FM modulator; a voltage variable capacitor forming a part of said FM modulator and said voltage variable capacitor connected to said frequency controlling circuit of said carrier frequency oscillator; and an integrating circuit receiving an input from said tone oscillator and supplying an output to said voltage variable capacitor.
Claim 4
Dependent Claim
85 words
A transmitter for remote control comprising: a carrier frequency oscillator which includes a frequency contRolling circuit; a tone oscillator connected to said carrier frequency oscillator to key it on and off at the tone frequency; an FM modulator; a voltage variable capacitor forming a part of said FM modulator and said voltage variable capacitor connected to said frequency controlling circuit of said carrier frequency oscillator; and an integrating circuit receiving an input from said tone oscillator and supplying an output to said voltage variable capacitor.
Claim 5
Dependent Claim
34 words
A transmitter according to claim 1 wherein said integrating circuit comprises a resistor in series between said voltage variable capacitor and said tone oscillator and a capacitor connected in parallel with said tone oscillator.
Claim 6
Dependent Claim
83 words
A transmitter for remote control comprising: a carrier frequency oscillator which includes a frequency controlling circuit; a tone oscillator connected to said carrier frequency oscillator to key it on and off at the tone frequency; an FM modulator; a voltage variable capacitor forming a part of said FM modulator and connected to an output of said tone oscillator; and said frequency controlling circuit including a split stator capacitor having two capacitor portions and said voltage variable capacitor connected between said two capacitor portions.
Claim 7
Dependent Claim
83 words
A transmitter for remote control comprising: a carrier frequency oscillator which includes a frequency controlling circuit; a tone oscillator connected to said carrier frequency oscillator to key it on and off at the tone frequency; an FM modulator; a voltage variable capacitor forming a part of said FM modulator and connected to an output of said tone oscillator; and said frequency controlling circuit including a split stator capacitor having two capacitor portions and said voltage variable capacitor connected between said two capacitor portions.
Claim 8
Dependent Claim
24 words
A transmitter according to claim 3 wherein said split stator variable capacitor includes means for simultaneously varying the capacitance of said two capacitor positions.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-02-13 | 1976-08-14 | 1977-02-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-02-13 | 1980-08-14 | 1981-02-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-02-13 | 1984-08-14 | 1985-02-13 | $7700.00 | Window Closed / Lapsed |