Detonator assembly
AssigneeDetnet South Africa (Pty) Ltd
InventorsElmar Lennox MULLER, Abraham Johannes LIEBENBERG
Life of this patent
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Abstract
A detonator assembly which includes a detonator arrangement comprising a detonator, a receiver which is responsive to a magnetic signal from a control centre and a control circuit which, in response to a signal from the receiver, regulates firing of the detonator, and which is characterised in that a fibre optic cable is connected to and extends from the detonator arrangement, and in that the detonator arrangement includes a transmitter/receiver module which is in signal communication with the fibre optic cable and the control circuit.
Claims6
1-4. (canceled)
A blast site (10) which includes a blast controller (22) at a control centre (24), a plurality of spaced apart at boreholes (12), a magnetic signal transmitter (18), a loop antenna (16) which surrounds the boreholes (12) and which is connected to the magnetic signal transmitter (18) and a plurality of detonator assemblies (26), each detonator assembly (26) being associated with a respective borehole (12) and including a detonator arrangement (28) which is positioned inside a borehole (12) and which comprises a housing (30) and, positioned inside or attached to, the housing (30) a detonator (52), a control circuit (48) and a transmitter/receiver module (44) which is in signal communication with the control circuit (48), a fibre optic cable (32) which is connected at a first end to the detonator arrangement (28), and a communication interface (42) which, in use, is formed at a second end of the fibre optic cable (32) at a mouth (43) of the borehole, characterised in that, in respect of each detonator assembly (26) the module (44) is capable of bidirectional communication via the fibre optic cable (32) at light frequency via the communication interface (42) with a mobile interrogating device and in that each detonator arrangement (28) respectively includes, positioned inside or attached to the housing (30) a magnetic signal receiver (46) which is responsive to a magnetic signal transmitted by the magnetic signal transmitter (18) which functions under the control of the blast controller (22), and in that the control circuit (48), in response to a signal from the magnetic signal receiver (46) regulates firing of the detonator (52).
A method of operating a detonator assembly (26) which includes a detonator arrangement (28) and a fibre optic cable (32) which at a first end is connected to the detonator arrangement (28) and which at a second opposing end forms a communication interface (42), wherein the method includes the steps of deploying the detonator arrangement (28) in a borehole (12) whereby the fibre optic cable (32) extends in the borehole from the detonator arrangement (28) and the communication interface (42) is located at a mouth (43) of the borehole (12), engaging in two-way communication at a light frequency with the detonator arrangement (28) via the communication interface (42) and, when required, of transmitting a fire command to a magnetic signal receiver (46) in the detonator arrangement (28) using a through-the-earth magnetic signal from a magnetic signal transmitter (18) at a control centre (24).
A method of establishing and operating a blast site which includes the steps of forming a plurality of spaced apart boreholes at the site, placing a loop antenna (16) to surround the boreholes, connecting a magnetic signal transmitter to the loop antenna, providing a plurality of detonator assemblies (26) and placing each detonator assembly (26) into a respective borehole (12) characterised in that, for each detonator assembly (26) two-way communication with a control circuit in the detonator assembly is established by means of a mobile interrogating unit, carried by an operator, which is coupled to a respective communication interface in the detonator assembly whereby signals are transmitted at a light frequency via a fibreoptic cable (32) between the interrogating unit and a respective transmitter/receiver module (44) in the detonator assembly and in that, when required, of transmitting a fire command to a magnetic signal receiver in the detonator assembly using a through-the-earth magnetic signal from the magnetic signal transmitter.
Dependencies are inferred from the claim text.