US4968978A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Long range multiple point wireless control and monitoring system
Assignee: Stolar Inc
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Filing: 1988-09-02
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Granted: 1990-11-06
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Expires: 2008-09-02
Abstract
Abstract A method for remotely monitoring conditions such as carbon monoxide for methane gas concentration, longwall roof support pressure, machine parameters or uncut coal, trona or potash layer thickness in a natural resource mining system such as a longwall or continuous mine system. The method utilizes a plurality of sensors connected to low magnetic moment transmitters, e.g. 0.1 ATM2, or high magnetic moment transmitters, e.g. 2.5 ATM2, that transmit collected data during multiple short burst transmission periods. Prior to transmission, the data is converted to a digital word format. An algorithm in the transmitter microcomputer ensures that random time intervals exist between data transmission bursts thus preventing a data transmission clash at the central receiver. A microcomputer algorithm in the central receiver protects against data contention caused by simultaneous transmission from several sensors. The data is transmitted to the central receiver either through a natural waveguide pathway or through a utility conductor that is magnetically coupled to the transmitter and central receiver by properly oriented electrically short magnetic dipole antennas. The method can be used, for example, to automatically control the positioning of a plurality of longwall roof supports or to transmit data from a longwall drillhead, along the drill rod, to the central receiver. Data can be communicated between a remote location and a surface area by utilizing a system of repeaters inductively coupled to a utility conductor. Use of the repeater system permits operation of mining machines from a surface computer.
Inventors
- 👤 Larry G. Stolarczyk
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 02:49
CPC Classifications
E; E21; E21D; E21D23/00; E21D23/12; E21C; E21C35/00; E21C35/282; E21C35/302; E21D23/14; E21D23/148; E21F; E21F17/00; E21F17/18; G; G08; G08C; G08C15/00; G08C17/00; G08C17/04; G08C23/00; G08C2201/00; G08C2201/40; G08C2201/50; G08C2201/51
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
156 words
A method for remotely monitoring conditions in a natural resource deposit which comprises: placing a sensor near an area to be monitored; inductively coupling a sensor transmitter to a conductor using an electrically short magnetic dipole antenna; periodically supplying power to the sensor transmitter and to the sensor during a power-on period; monitoring conditions in said area to be monitored by collecting data with the sensor during said power-on period; converting said data collected by the sensor to a digital format; activating the sensor transmitter for a time interval sufficient to transmit a transmitted digital word, comprised of at least some of said data collected by the sensor during said power-on period, to a central receiver; forming a first narrow-band frequency modulated signal by using said first digital word to frequency modulate a carrier signal; and transmitting said first modulation signal during said power-on period, from the sensor transmitter, through said conductor, to said central receiver.
Claim 2
Independent Claim
156 words
A method for remotely monitoring conditions in a natural resource deposit which comprises: placing a sensor near an area to be monitored; inductively coupling a sensor transmitter to a conductor using an electrically short magnetic dipole antenna; periodically supplying power to the sensor transmitter and to the sensor during a power-on period; monitoring conditions in said area to be monitored by collecting data with the sensor during said power-on period; converting said data collected by the sensor to a digital format; activating the sensor transmitter for a time interval sufficient to transmit a transmitted digital word, comprised of at least some of said data collected by the sensor during said power-on period, to a central receiver; forming a first narrow-band frequency modulated signal by using said first digital word to frequency modulate a carrier signal; and transmitting said first modulation signal during said power-on period, from the sensor transmitter, through said conductor, to said central receiver.
Claim 3
Dependent Claim
12 words
The method of claim 1 wherein said conductor comprises a utility conductor.
Claim 4
Dependent Claim
12 words
The method of claim 1 wherein, said conductor comprises a natural waveguide.
Claim 5
Dependent Claim
47 words
The method of claim 1 further including the steps of: deactivating said sensor transmitter after transmitting said first modulated signal; and reactivating said sensor transmitter at a random time interval and retransmitting said first modulated signal as a second modulated signal identical to said first modulated signal.
Claim 6
Dependent Claim
80 words
The method of claim 4 further including the step of: receiving said first modulated signal and said second modulated signal at said central receiver; demodulating said first modulated signal after it is received and demodulating said second modulated signal after it is received to yield a first received digital word and a second received digital word, respectively; and ensuring the validity of said first received digital word by comparing said first received digital word to said second received digital word.
Claim 7
Dependent Claim
42 words
The method of claim 5 further comprising: verifying that a first received digital word is contains a predetermined number of bits; and verifying that the parity of said first received digital word is identical to the parity of said transmitted digital word.
Claim 8
Dependent Claim
19 words
The method of claim 1 wherein said carrier frequency is in the range of 30 kHz to 3 MHz.
Claim 9
Dependent Claim
23 words
The method of claim 1 wherein said first modulated signal is formed by utilizing a two-frequency modulation signal to modulate said carrier signal.
Claim 10
Dependent Claim
17 words
The method of claim 1 wherein said electrically short magnetic dipole antenna is a tuned loop antenna.
Claim 11
Independent Claim
128 words
A method for remotely monitoring conditions in a natural resource deposit which comprises: placing a sensor near an area to be monitored; periodically supplying power to a sensor transmitter and to the sensor; monitoring conditions in said area to be monitored by collecting data with the sensor; converting said data collected by the sensor to a digital word; activating the sensor transmitter for a time interval sufficient to transmit said digital word; transmitting said digital word from the sensor transmitter over an electrical conductor to a central receiver using an electrically short magnetic dipole antenna to couple the sensor transmitter to said electrical conductor; deactivating the sensor transmitter after transmitting said digital word; and reactivating the sensor transmitter at a random time interval and retransmitting said digital word.
Claim 12
Independent Claim
128 words
A method for remotely monitoring conditions in a natural resource deposit which comprises: placing a sensor near an area to be monitored; periodically supplying power to a sensor transmitter and to the sensor; monitoring conditions in said area to be monitored by collecting data with the sensor; converting said data collected by the sensor to a digital word; activating the sensor transmitter for a time interval sufficient to transmit said digital word; transmitting said digital word from the sensor transmitter over an electrical conductor to a central receiver using an electrically short magnetic dipole antenna to couple the sensor transmitter to said electrical conductor; deactivating the sensor transmitter after transmitting said digital word; and reactivating the sensor transmitter at a random time interval and retransmitting said digital word.
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) | 1993-11-05 | 1994-05-07 | 1994-11-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-11-05 | 1998-05-07 | 1998-11-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-11-05 | 2002-05-07 | 2002-11-06 | $7700.00 | Window Closed / Lapsed |