Long range multiple point wireless control and monitoring system

• US 5,087,099 A
• Filed: 08/16/1990
• Issued: 02/11/1992
• Est. Priority Date: 09/02/1988
• Status: Expired due to Fees

• Current Assignee: Stolar Incorporated
• Original Assignee: Stolar Incorporated
• Inventors: Stolarczyk, Larry G.
• Primary Examiner(s): Bagnell, David J.
• Application Number:
  US07/557,907
• Time in Patent Office: 544 Days
• Field of Search: 299/1, 299/30, 367/6, 367/127, 367/128, 367/76, 367/78, 367/80, 340/825.4, 375/6, 455/40, 455/20, 455/21, 455/22, 342/42, 342/50
• US Class Current: 299/1.6
• CPC Class Codes: E21C 35/24 Remote control specially adapted for machines for slitting or completely freeing the mineral control in general G05
• CPC Class Codes: E21D 23/12 Control, e.g. using remote control E21D23/16 takes precedence
• CPC Class Codes: E21D 23/148 Wireless transmission of signals or commands
• CPC Class Codes: E21F 17/18 Special adaptations of signalling or alarm devices for mine lifts B66B; gas-sensitive devices per se G01N
• CPC Class Codes: G08C 15/00 Arrangements characterised by the use of multiplexing for the transmission of a plurality of signals over a common path
• CPC Class Codes: G08C 17/04 using magnetically coupled devices
• CPC Class Codes: G08C 2201/40 Remote control systems using repeaters, converters, gateways
• CPC Class Codes: G08C 2201/51 Remote controlling of devices based on replies, status thereof
• CPC Class Codes: G08C 23/00 Non-electrical signal transmission systems, e.g. optical systems

Abstract

A method for remotely monitoring conditions such as carbon monoxide or 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.

Claims

1. A method of mine wide data transmission which comprises:

inductively coupling a plurality of first repeaters to an electrical conductor running from a surface area to a mine;

inductively coupling a plurality of second repeaters to said electrical conductor;

transmitting a data signal from a base station at a frequency F₂ to one of the first repeaters, said data signal comprising a digitally encoded word;

retransmitting the data signal from one of the first repeaters at a frequency F₃ to one of the second repeaters;

retransmitting the data signal from one of the second repeaters at a frequency F₁ to a remote monitoring and control unit;

decoding the digitally encoded word in the remote monitoring and control unit; and

checking an address characteristic of the digitally encoded word before accepting the digitally encoded word.

2. The method of claim 1 further including the step of:

using the digitally encoded word to activate a plurality of output circuits in the remote monitoring and control unit.

3. The method of claim 1 further including the step of:

using the plurality of output circuits to activate an electrohydraulic control system of a machine.

4. A method of mine wide data transmission which comprises:

inductively coupling a plurality of first repeaters to an electrical conductor running from a surface area to a mine;

inductively coupling a plurality of second repeaters to said electrical conductor;

transmitting a data signal from a base station at a frequency F₂ to one of the first repeaters;

retransmitting the data signal from one of the first repeaters at a frequency F₃ to one of the second repeaters;

retransmitting the data signal from one of the second repeaters at a frequency F₁ to a remote monitoring and control unit;

inputting an input signal into an input circuit of the remote monitoring and control unit;

transmitting the input signal to one of the first repeaters at the frequency F₂ ;

retransmitting the input signal from one of the first repeaters at the frequency F₃ to one of the second repeaters; and

retransmitting the input signal from one of the second repeaters at the frequency F₁ to the base station.

5. A method of mine data transmission which comprises:

inductively coupling a first repeater to an electrical conductor running from a first location to a second location within a mine;

inductively coupling a second repeater to said electrical conductor;

transmitting a data signal from a first station at a frequency F₁ to the first repeater, said data signal comprising a digitally encoded word;

retransmitting the data signal from the first repeater at a frequency F₂ to the second repeater;

retransmitting the data signal from the second repeater at a frequency F₃ to a remote monitoring and control unit;

decoding the digitally encoded word in the remote monitoring and control unit; and

checking an address characteristic of the digitally encoded word before accepting the digitally encoded word.

6. The method of claim 5 further including the step of:

using the digitally encoded word to activate a plurality of output circuits in the remote monitoring and control unit.