Communications: electrical – Continuously variable indicating – With meter reading
Reexamination Certificate
1998-03-24
2001-07-24
Holloway, III, Edwin C. (Department: 2635)
Communications: electrical
Continuously variable indicating
With meter reading
C340S870030, C340S005220, C455S151200, C341S176000
Reexamination Certificate
active
06265987
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to a remote control device, more particularly to a learning-type remote control device which is capable of detecting both the carrier frequency and the control code in a remote control signal that is transmitted by another remote control device, and which is capable of generating remote control signals of different carrier frequencies.
2. Description of the Related Art
Remote control devices, such as those used in the control of garage doors and car alarms, have become an indispensable part of our daily lives. Therefore, there is always a need to make back-up remote control devices in order to avoid replacement of the entire remote control system in the event that a remote control device has been misplaced.
U.S. Pat. No. 5,237,319 discloses a remote control device having a learning function in which a remote control signal transmitted from another remote control device is received to perform learning and to transmit a new remote control signal on the basis of the learning. When making a copy of a target remote control device, the learning-type remote control device is capable of learning a control code that is present in a remote control signal from the target remote control device. Thus, the learning-type remote control device is more convenient to program than one having no learning function. However, the remote control signal of a remote control device further includes a carrier signal portion that is modulated by the control code. Presently, a separate instrument is needed to measure the carrier frequency of the target remote control device, and to set the conventional learning-type remote control device to the measured carrier frequency before a copy of the target remote control device can be made.
Measurement of the carrier frequency of the target remote control device, and setting of the conventional learning-type remote control device to the measured carrier frequency are time-consuming tasks that cannot be accomplished by the consumer without using a separate instrument. Moreover, the conventional learning-type remote control device can only generate remote control signals of the same carrier frequency, thereby limiting its utility.
SUMMARY OF THE INVENTION
Therefore, the main object of the present invention is to provide a learning-type remote control device which is capable of detecting both the carrier frequency and the control code in a remote control signal that is transmitted by another remote control device.
Another object of the present invention is to provide a learning-type remote control device that is capable of generating remote control signals of different carrier frequencies.
Accordingly, the learning-type remote control device of this invention is capable of detecting both carrier frequency and control code in a remote control signal that is transmitted by a target remote control device, and comprises a control key unit, a memory unit, a digital-to-analog converting unit, a variable frequency oscillating unit, a mixing unit, a signal detecting unit, and a processing unit.
The control key unit includes a plurality of control keys. The memory unit has a plurality of memory spaces for storing a plurality of frequency counts and a plurality of control codes that correspond respectively to the control keys. The digital-to-analog converting unit converts a frequency count input into a frequency control signal. The variable-frequency oscillating unit is connected to the digital-to-analog converting unit and is operable so as to generate a carrier signal having a frequency which varies according to magnitude of the frequency control signal. The variable-frequency oscillating unit is further operable so as to modulate the carrier signal according to a control signal that is provided thereto. The mixing unit is adapted to wirelessly receive the carrier signal from the variable-frequency oscillating unit and the remote control signal from the target remote control device, and to generate a mixed signal by mixing the carrier signal with the remote control signal. The signal detecting unit is connected to the mixing unit for generating a detected frequency signal and a detected control signal from the mixed signal. The detected frequency signal indicates when the frequency of the carrier signal from the variable-frequency oscillating unit approaches lower and upper sideband frequencies of the remote control signal from the target remote control device. The detected control signal contains the control code of the remote control signal from the target remote control device. The processing unit is connected to the control keys, the memory unit, the digital-to-analog converting unit, the variable-frequency oscillating unit and the signal detecting unit. The processing unit is operable selectively in a learning mode and a signal generating mode in response to user operation of the control key unit.
When operated in the learning mode, the processing unit provides the frequency count input to the digital-to-analog converting unit. The processing unit varies the frequency count input to the digital-to-analog converting unit, and detects a minimum value of the frequency count input during which the detected frequency signal from the signal detecting unit reaches a preset threshold voltage as a lower sideband frequency count, and a maximum value of the frequency count input during which the detected frequency signal from the signal detecting unit reaches the preset threshold voltage as an upper sideband frequency count. The processing unit determines a frequency count that corresponds to the carrier frequency of the remote control signal transmitted by the target remote control device from the lower and upper sideband frequency counts. The processing unit further determines the control code in the remote control signal transmitted by the target remote control device from the detected control signal of the signal detecting unit. The processing unit stores the frequency count and the control code determined thereby in one of the memory spaces of the memory unit corresponding to an operated one of the control keys.
When operated in the signal generating mode, the processing unit retrieves the frequency count and the control code of an operated one of the control keys from the corresponding one of the memory spaces in the memory unit. The frequency count retrieved by the processing unit is provided to the digital-to-analog converting unit as the frequency count input. The control code retrieved by the processing unit is converted thereby into the control signal that is provided to the variable-frequency oscillating unit.
REFERENCES:
patent: 5227780 (1993-07-01), Tigwell
patent: 5237319 (1993-08-01), Hidaka
patent: 5379453 (1995-01-01), Tigwell
patent: 5475366 (1995-12-01), Van Lente et al.
patent: 6021319 (2000-02-01), Tigwell
patent: WO 94/02920 (1994-02-01), None
Hsu Jui-Hung
Wang Mao-Shen
Dougherty & Troxell
Holloway III Edwin C.
LandOfFree
Remote control device with learning function does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Remote control device with learning function, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Remote control device with learning function will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2544622