US 4,330,154 AGranted

Mining apparatus

AssigneeDowty Mining Equipment Limited

InventorRobert G. Harris

Life of this patent

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Abstract

A control means for use in a mining apparatus includes a radiation-emitting device on a cutting machine, a number of receiving devices, one associated with each roof support of the apparatus, for receiving radiation from the radiation-emitting device as the machine passes a receiving device, whereby a main control signal is generated, and advance-initiating means for each roof support, responsive to a command signal. A main conductor is connected to the receiving devices for carrying a main control signal, and disabling means is associated with each advance-initiating means and main conductor for rendering a said advance-initiating means non-responsive to a command signal applied to that means when the main control signal is above a pre-determined value. Attenuating means associated with the main conductor between each pair of roof supports is provided for gradually reducing the main control signal to a value below said pre-determined value.

Claims3

Dependent claims

For use in a mining apparatus including a cutting machine and a plurality of roof supports, each having an advance-initiating means responsive to a command signal for controlling the advance of the roof support, arranged side-by-side along a mineral face to be cut by the machine, a control means comprising:

(a) a radiation-emitting device associated with the cutting machine,
(b) a plurality of receiving devices, one associated with each roof support, capable of receiving radiation emitted from the radiation-emitting device as the cutting machine passes in proximity to a receiving device and capable of generating a main electrical control signal in response to the receipt of such radiation,
(c) a main control conductor connected to the receiving devices for carrying a main electrical control signal,
(d) disabling means associated with each advance-initiating means and with the main control conductor for rendering an advance-initiating means non-responsive to a command signal applied to the advance-initiating means when the main electrical control signal is above a pre-determined value, and
(e) attenuating means associated with the main control conductor between each pair of roof supports for attenuating the main electrical control signal to a value below the said pre-determined value when that signal has passed a pre-determined number of attenuating means from a receiving device receiving radiation from the radiation-emitting device.

2 more elements

Dependencies are inferred from the claim text.

Facts

Application: 06/210,001Filed 24 Nov 1980
Priority: GB 794039022 Nov 1979
Granted: 18 May 1982
Term ends: Not estimatedThe source records don’t support an estimate.

Classification6 codes

E21D 23/14
Control, e.g. using remote control: effecting automatic sequential movement of supports, e.g. one behind the other
E21D 23/142
Effecting automatic sequential movement of supports, e.g. one behind the other: measuring the advance of support units with respect to external…
E21D 23/146
Effecting automatic sequential movement of supports, e.g. one behind the other: transmission of signals and commands by cable
E21F 13/086
Shifting conveyors or other transport devices from one location at the working face to another: armoured conveyors shifting devices