REMOTE FIRING SYSTEM FOR NON-ELECTRIC DETONATORS USING ELECTRONIC INITIATORS

Abstract

A firing system comprising an electronic initiator, and a blasting unit connected to and capable to initiate the electronic initiator, wherein the electronic initiator comprises an external housing made of plastics, an explosive charge, a fuse head and an electronic delay element, the external housing comprising an inner cavity and retaining means adapted to retain at least one shock tube, the explosive charge, the fuse head and the electronic delay element being located in the inner cavity of the external housing, the explosive charge being located at a closed end of the inner cavity, at a position such that the explosive charge is capable to ignite the shock tubes retained by the retaining means in a use situation of the electronic initiator, the fuse head and the explosive charge being located relative to each other such that the fuse head is capable to ignite the explosive charge, and the electronic delay element being connected to the fuse head and being configured to initiate it.

Claims

1. A firing system comprising: at least one electronic initiator, and a blasting unit connected to the at least one electronic initiator through at least one wire, wherein the electronic initiator comprises an external housing, an explosive charge, a fuse head and an electronic delay element, the external housing being made of plastics and comprising an inner cavity and retaining means adapted to retain at least one shocktube, the explosive charge, the fuse head and the electronic delay element being located in the inner cavity of the external housing, the explosive charge being located at a closed end of the inner cavity, at a position such that the explosive charge is capable to ignite the shocktubes retained by the retaining means in a use situation of the electronic initiator, and the fuse head and the explosive charge being located relative to each other such that the fuse head is capable to ignite the explosive charge, and the electronic delay element being connected to the fuse head and configured to initiate it, wherein the blasting unit is placed out of the external housing of the electronic initiator.

2. The firing system according to claim 1, wherein the electronic initiator further comprises a sealing plug located in the inner cavity, sealing an open end thereof.

3. The firing system according to claim 1, wherein the retaining means of the electronic initiator comprise at least one slot adapted to receive at least one shocktube.

4. The firing system according to claim 3, wherein the at least one slot is situated adjacent to the explosive charge.

5. The firing system according to claim 1, wherein the electronic delay element of the electronic initiator is an electronic circuit programmable to set a delay time.

6. The firing system according to claim 1, wherein the blasting unit is remotely controllable.

7. The firing system according to claim 1, further comprising a control unit adapted to remotely control the blasting unit to initiate the electronic initiator.

8. The firing system according to claim 1, comprising a plurality of electronic initiators connected to the blasting unit.

9. The firing system according to claim 8, wherein the electronic initiators are programmable to initiate respective blasts sequentially in time.

10. The firing system according to claim 1, comprising a plurality of blasting units and a plurality of electronic initiators, each blasting unit being connected to at least one electronic initiator.

11. The firing system according to claim 10, wherein the blasting units are programmable to initiate the electronic initiators sequentially in time.

12. The firing system according to claim 1, wherein the blasting unit comprises communication means configured to allow communication with at least one additional blasting unit.

13. The firing system according to claim 12, wherein the communication means are configured to operate in ad-hoc mode and/or in infrastructure network mode.

14. The firing system according to claim 1, wherein the weight of the explosive charge of an electronic initiator is less than 500 mg.

Description

DESCRIPTION OF THE DRAWINGS

[0025] These and other characteristics and advantages of the invention will become clearly understood in view of the detailed description of the invention which becomes apparent from preferred embodiments of the invention, given just as an example and not being limited thereto, with reference to the drawings.

[0026] FIG. 1 shows a schematic picture of a firing system according to an embodiment of the invention.

[0027] FIG. 2 shows a cross section of the electronic initiator according to an embodiment of the firing system of the invention.

[0028] FIG. 3 shows a cross section of an electronic initiator as the one shown in FIG. 2, retaining a number of shocktubes.

[0029] FIG. 4 shows a schematic picture of a firing system according to an embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION

[0030] FIG. 1 schematically shows a firing system according to an embodiment of the invention. In this embodiment, the firing system comprises an electronic initiator (1) and a blasting unit (10) connected through at least one wire (8) to the electronic initiator (1) and adapted to initiate the electronic initiator. The firing system further comprises a control unit (11) adapted to remotely control the blasting unit (10) to initiate the electronic initiator (1). In this embodiment the control of the blasting unit is based on wireless technology.

[0031] FIG. 2 shows an electronic initiator (1) according to an embodiment of the invention. The electronic initiator (1) comprises an external housing (2) made of plastics, an inner cavity and retaining means adapted to retain at least one shocktube. In this embodiment the external housing has two slots (7) for receiving each a plurality of shocktubes.

[0032] The electronic initiator (1) includes an explosive charge (5), a fuse head (3) and an electronic delay element (4) located within the inner cavity of the external housing (2). As shown in the figure, the external housing (2) has a closed end at which the explosive charge (5) is located. The explosive charge (5) is located relative to the retaining means such that the explosive charge (5) is capable to ignite the shocktubes retained by the retaining means in a use situation of the electronic initiator (1). In this embodiment the explosive charge (5) is located along an elongated portion of the inner cavity and the retaining means, configured as two slots, are adjacent and parallel to the explosive charge.

[0033] An electronic delay element (4) is connected to the fuse head (3) and is configured to initiate the fuse head (3) upon reception of an initiation voltage from a blasting unit through wires (8). The fuse head (3) and the explosive charge (5) are located relative to each other such that the initiated fuse head (3) is capable to ignite the explosive charge (5). The electronic delay element (4) is an electronic circuit programmable to set a delay time between reception of the initiation voltage and initiation of the fuse head.

[0034] A sealing plug (6) is located closing the open end of the inner cavity. The lead wires (8) connecting the electronic initiator (1) and the blasting unit (11) are located entering the inner cavity through the sealing plug (6).

[0035] FIG. 3 shows the cross section of the electronic initiator of FIG. 2, in a use situation as the one schematically depicted in FIG. 1, in which the electronic initiator is retaining a number of shocktubes (12). As visible in the figure, five shocktubes (12) are received in each slot (7), each shocktube (12) being placed in the slot (7) adjacent to the explosive charge (5) and substantially perpendicular to the slot direction. Each shocktube (12), when connected to a corresponding non-electric detonator, is intended to transmit the blast initiated in the electronic initiator to the non-electric detonator.

[0036] In a use situation of the firing system, upon emission of an initiation signal from the control unit (11), the blasting unit (10) powers the electronic initiator (1) through wires (8) with an initiation voltage which is sufficient to initiate the fuse head (3). The electronic delay element (4) may be configured to set a delay time prior to the initiation of the fuse head. Initiation of the fuse head (3) causes ignition of the explosive charge (5), thus producing a blast which is transmitted through the shocktubes (12) to a number of non-electric detonators. The shocktubes (12) retained by the retaining means of the electronic initiator (1) are schematically shown in FIG. 1. The non-electric detonators connected to the shocktubes (12) are not shown.

[0037] FIG. 4 shows a second embodiment of the firing system according to the invention. The firing system of this embodiment is like the one described in connection with FIG. 1, but in this embodiment the firing system includes a second blasting unit (10), in turn having an electronic initiator connected thereto. The presence of more than one blasting unit allows the firing system to assign time sequences between the blasting units. Additionally, in embodiments where each blasting unit is connected to several electronic initiators, time sequences can be assigned to the electronic initiators connected to each blasting unit, in order to define a sequence of blasts as required by the situation.