1. An intrinsically safe circuit for an electronic detonator comprising, electrically connected:

the input end of the current limiting module is connected with the detonator leg wire and is used for limiting the magnitude of current;

the input end of the transient suppression module is connected with the output end of the current limiting module and used for preventing surge pulse;

the input end of the rectification module is connected with the output end of the transient suppression module and is used for converting alternating current into direct current;

the input end of the blocking module is connected with the output end of the rectifying module and is used for preventing the energy storage module at the control end of the electronic detonator from discharging to the detonator leg wire;

and the transmitting and receiving auxiliary module is connected to the output end of the blocking module and is used for clamping the output signal.

2. An intrinsically safe circuit for an electronic detonator as claimed in claim 1, wherein: the current limiting module comprises a first resistor and a second resistor, the first resistor and the second resistor are respectively any one of a current limiting resistor or a FUSE resistor, and first ends of the first resistor and the second resistor are respectively connected with the two detonator leg wires.

3. An intrinsically safe circuit for an electronic detonator as claimed in claim 2, wherein: the transient suppression module comprises a TVS diode, and the second ends of the first resistor and the second resistor are respectively connected with the TVS diode.

4. An intrinsically safe circuit for an electronic detonator as claimed in claim 3, wherein: the TVS diode is a bidirectional TVS diode, the second end of the first resistor is connected with the first end of the bidirectional TVS diode, and the second end of the second resistor is connected with the second end of the bidirectional TVS diode.

5. An intrinsically safe circuit for an electronic detonator as claimed in claim 2, wherein: the rectifying module comprises a full-wave rectifying circuit, the full-wave rectifying circuit comprises four connected diodes D1, D2, D3 and D4, and second ends of the first resistor and the second resistor are respectively connected to input ends of the rectifying module.

6. An intrinsically safe circuit for an electronic detonator as claimed in claim 1, wherein: the blocking module comprises a blocking diode, the output end of the rectifying module is respectively connected with the anode of the blocking diode, and the cathode of the blocking diode is connected with the control end of the electronic detonator.

7. An intrinsically safe circuit for an electronic detonator as claimed in claim 1, wherein: the transceiver auxiliary module comprises any one of a pull-down resistor or a pull-up resistor.

8. A time delay device for an electronic detonator comprising the intrinsically safe circuit of claim 1, a detonator pin wire connected to the intrinsically safe circuit and then to a control terminal, the control terminal comprising:

the signal input end of the delay control chip is connected with the output end of the intrinsic safety circuit;

the input end of the energy storage module is connected with the output end of the intrinsic safety circuit, and the output end of the energy storage module is connected with the ignition switch;

the ignition switch is connected with the signal output end of the delay control chip;

the ignition element is connected with the ignition switch and is used for igniting the ignition powder head.

9. A time delay device for an electronic detonator as claimed in claim 8, wherein: the delay control chip adopts an ASIC chip, the energy storage module adopts an energy storage capacitor, the ignition element is one of an ignition resistor or a rigid explosive head, and the ignition switch is one of an MOS (metal oxide semiconductor) tube, a triode or a field effect tube.

10. A time delay device for an electronic detonator as claimed in claim 9, wherein: the control end further comprises a chip protection circuit, the chip protection circuit comprises a protection resistor, and the protection resistor is arranged at the voltage input end and the signal output end of the time delay control chip.

Background

According to the specification of GB3836.4-2010, an intrinsically safe circuit is a circuit which, under specified test conditions, neither electrical sparks nor thermal effects which occur during normal operation or in specified fault conditions can ignite a specified explosive gas mixture, and is the safest of the explosion-proof electrical devices, since even in fault conditions it does not detonate, i.e. is "intrinsically" safe, and is therefore called intrinsically safe, called intrinsically safe for short.

In special industries such as coal mines or mines, ignition risks cannot be caused by high temperature or sparks of the whole product under any conditions, the problem of detonator loss exists in the currently used allowable electric detonators for coal mines, serious social safety hazards exist, various measures are taken by national regulatory authorities to prevent the occurrence of the events, and the most effective measure is to comprehensively popularize the electronic detonators to replace common detonators. However, the common electronic detonators do not pass coal safety certification, and have huge potential safety hazards in production when used in underground coal mines and combustible and explosive gas environments, and cannot meet the requirements of intrinsic safety, so that the electronic delay detonators are not popularized and used in underground blasting operation on a large scale, and therefore, the development of the electronic detonators meeting the requirements of intrinsic safety is an urgent need in the popularization process of the electronic detonators at present.

Disclosure of Invention

Aiming at the problems, the invention provides an intrinsic safety circuit and a time delay device for an electronic detonator, which can eliminate the potential production safety hazard of the electronic detonator in coal mine operation and have high safety coefficient.

The technical scheme is as follows: an intrinsically safe circuit for an electronic detonator comprising, electrically connected:

the input end of the current limiting module is connected with the detonator leg wire and is used for limiting the magnitude of current;

the input end of the transient suppression module is connected with the output end of the current limiting module and used for preventing surge pulse;

the input end of the rectification module is connected with the output end of the transient suppression module and is used for converting alternating current into direct current;

the input end of the blocking module is connected with the output end of the rectifying module and is used for preventing the energy storage module at the control end of the electronic detonator from discharging to the detonator leg wire;

and the transmitting and receiving auxiliary module is connected to the output end of the blocking module and is used for clamping the output signal.

Further, the current limiting module includes a first resistor and a second resistor, the first resistor and the second resistor are any one of a current limiting resistor or a FUSE resistor, and first ends of the first resistor and the second resistor are connected to the two detonator leg wires respectively.

Further, the transient suppression module includes a TVS diode, and second ends of the first resistor and the second resistor are respectively connected to the TVS diode.

Further, the TVS diode is a bidirectional TVS diode, a second end of the first resistor is connected to a first end of the bidirectional TVS diode, and a second end of the second resistor is connected to a second end of the bidirectional TVS diode.

Further, the rectification module comprises a full-wave rectification circuit, the full-wave rectification circuit comprises four connected diodes D1, D2, D3 and D4, and second ends of the first resistor and the second resistor are respectively connected to the input end of the rectification module.

Furthermore, the blocking module comprises a blocking diode, the output end of the rectifying module is respectively connected with the positive electrode of the blocking diode, and the negative electrode of the blocking diode is connected with the control end of the electronic detonator.

Further, the transceiver auxiliary module includes any one of a pull-down resistor and a pull-up resistor.

A time delay device for an electronic detonator, comprising the intrinsic safety circuit, wherein a detonator pin wire is connected to a control terminal after being connected to the intrinsic safety circuit, and the control terminal comprises:

the signal input end of the delay control chip is connected with the output end of the intrinsic safety circuit;

the input end of the energy storage module is connected with the output end of the intrinsic safety circuit, and the output end of the energy storage module is connected with the ignition switch;

the ignition switch is connected with the signal output end of the delay control chip;

the ignition element is connected with the ignition switch and is used for igniting the ignition powder head.

Furthermore, the delay control chip adopts an ASIC chip, the energy storage module adopts an energy storage capacitor, the ignition element is one of an ignition resistor or a rigid explosive head, and the ignition switch is one of an MOS (metal oxide semiconductor) tube, a triode or a field effect tube.

Furthermore, the control end further comprises a chip protection circuit, the chip protection circuit comprises a protection resistor, and the protection resistor is arranged at the voltage input end and the signal output end of the time delay control chip.

The intrinsic safety circuit for the electronic detonator can be used as an interface circuit, is additionally arranged in the electronic detonator, can be used as a general scheme of a two-wire electronic detonator communication protocol, and has the advantages of small volume and strong transportability, the intrinsic safety circuit limits the current by arranging the current limiting module, prevents surge pulse by arranging the transient suppression module, and prevents the energy of the energy storage module from being reversely filled back to the foot wire end of the electronic detonator when the circuit is in fault by arranging the blocking module, thereby achieving the purpose of intrinsic safety and solving the problem that the common electronic detonator is easy to generate gas and coal dust explosion under the coal mine operation; the intrinsic safety circuit is applied to the time delay device of the electronic detonator, so that the electronic detonator can meet the requirement of intrinsic safety, is particularly suitable for coal mine operation, and has strong practicability, simplicity, convenience and easy popularization.

Drawings

FIG. 1 is a block diagram of an intrinsically safe circuit for an electronic detonator in one embodiment;

fig. 2 is a circuit diagram of an intrinsically safe circuit for an electronic detonator in embodiment 1;

fig. 3 is a circuit diagram of an intrinsically safe circuit for an electronic detonator in an embodiment 2;

fig. 4 is a block diagram of a delay device for an electronic detonator in one embodiment.

Detailed Description

The technical solutions of the present invention will be described clearly and completely with reference to the accompanying drawings, wherein the drawings provided in the present embodiments illustrate the basic idea of the invention only in a schematic way, and the components related to the present invention are only shown in the drawings rather than drawn according to the number, shape and size of the components in actual implementation, and the form, number and proportion of the components in actual implementation may be changed freely, and the layout of the components may be more complex.

Referring to fig. 1, an intrinsically safe circuit for an electronic detonator comprises, electrically connected:

the input end of the current limiting module 1 is connected with the detonator leg wire 100, so that the current can be limited;

the input end of the transient suppression module 2 is connected with the output end of the current limiting module 1 and is used for preventing surge pulse;

the input end of the rectifying module 3 is connected with the output end of the transient suppression module 2 and is used for converting alternating current into direct current;

and the input end of the blocking module 4 is connected with the output end of the rectifying module 3 and is used for preventing the energy storage module at the control end of the electronic detonator from discharging to the detonator leg wire 100.

And the transmitting and receiving auxiliary module is connected to the output end of the blocking module and is used for clamping the output signal.

Example 1:

referring to fig. 2, in particular, in one embodiment of the present invention, the intrinsically safe circuit is configured as follows:

the current limiting module 1 comprises a first resistor R3 and a second resistor R4, in the embodiment, the first resistor R3 and the second resistor R4 respectively adopt current limiting resistors, and the 1 st ends of the first resistor R3 and the second resistor R4 are respectively connected with two detonator leg wires BUS1 and BUS 2;

the transient suppression module 2 includes a TVS diode D7, and the 2 nd ends of the first resistor and the second resistor are respectively connected to the TVS diode D7, specifically in this embodiment, the TVS diode D7 is a bidirectional TVS diode, the 2 nd end of the first resistor R3 is connected to the 1 st end of the bidirectional TVS diode, and the 2 nd end of the second resistor R4 is connected to the 2 nd end of the bidirectional TVS diode D7;

the rectifying module 3 comprises a full-wave rectifying circuit, the full-wave rectifying circuit comprises four connected diodes D1, D2, D3 and D4, the 2 nd end of a first resistor R3 is connected between the diodes D1 and D3, the 2 nd end of a second resistor R4 is respectively connected between the diodes D2 and D4, and the rectifying module can supply power to a control terminal and charge an energy storage module at a control terminal;

the blocking module 4 comprises blocking diodes D5 and D6, the anode of the blocking diode D5 is connected between the diodes D1 and D3, the anode of the blocking diode D6 is connected between the diodes D2 and D4, and the cathodes of the blocking diodes D5 and D6 are respectively connected to the control end of the electronic detonator.

In this embodiment, the transceiver module includes a pull-down resistor, and the specific setting is: the 1 st ends of the pull-down resistors R5 and R6 are connected with the output end of the blocking module, and the 2 nd ends of the pull-down resistors R5 and R6 are grounded. When receiving a command, if the signal input terminal IN1 of the control terminal is at high level and IN2 is floating, the pull-down resistor R6 provides a default level for the signal input terminal IN 2; if the signal input terminal IN2 is high and the pull-down resistor IN1 is floating, R5 provides a default level for IN 1.

Example 2:

referring to fig. 3, in another embodiment of the present invention, the intrinsically safe circuit is arranged as follows:

the current limiting module 1 comprises a first resistor R3 and a second resistor R4, in the embodiment, the first resistor R3 and the second resistor R4 respectively adopt FUSE resistors, and the 1 st ends of the first resistor R3 and the second resistor R4 are respectively connected with two detonator leg wires BUS1 and BUS 2;

the transient suppression module 2 includes a TVS diode D7, and the 2 nd ends of the first resistor and the second resistor are respectively connected to the TVS diode D7, specifically in this embodiment, the TVS diode D7 is a bidirectional TVS diode, the 2 nd end of the first resistor R3 is connected to the 1 st end of the bidirectional TVS diode, and the 2 nd end of the second resistor R4 is connected to the 2 nd end of the bidirectional TVS diode D7;

the rectifying module 3 comprises a full-wave rectifying circuit, the full-wave rectifying circuit comprises four connected diodes D1, D2, D3 and D4, the 2 nd end of a first resistor R3 is connected between the diodes D1 and D3, the 2 nd end of a second resistor R4 is respectively connected between the diodes D2 and D4, and the rectifying module can supply power to a control terminal and charge an energy storage module at a control terminal;

the blocking module 4 comprises blocking diodes D5 and D6, the anode of the blocking diode D5 is connected between the diodes D1 and D3, the anode of the blocking diode D6 is connected between the diodes D2 and D4, and the cathodes of the blocking diodes D5 and D6 are respectively connected to the control end of the electronic detonator.

In this embodiment, the transceiver module includes a pull-up resistor, and the specific setting is: the 1 st ends of pull-up resistors R7 and R8 are connected with the output end of the blocking module, and the 2 nd ends of pull-up resistors R7 and R8 can be connected with the energy storage module.

The electronic detonator adopting the intrinsically safe circuit of the embodiment 2 is tested, and the test contents comprise:

1. the direct current resistance performance is as follows:

2 FUSE resistors of 4.7K are used, and are combined with a clamping function of a chip pin at the input of 48V to form an internal loop, and the FUSE resistors can overflow 5mA and are not fused.

2. The alternating current resistance performance is as follows:

and applying 220V/50Hz alternating current voltage to the electronic detonator, keeping the voltage for 10s, and preventing the electronic detonator from exploding.

When 2 FUSE resistors with 4.7K are used, when 220V alternating current is applied to a pin wire, the inner part of an input pin of the chip 2 is clamped to form a loop, the current flowing through the FUSE resistors is about 30mA, the FUSE current is blown, the FUSE occurs, the loop is immediately damaged, no current flows through a back-end circuit, and the back-end circuit cannot be damaged.

3. Electrostatic sensitivity:

3.1. under the conditions of 500pF of capacitance, 5000 omega of series resistance and 25KV of charging voltage, the electronic detonator is discharged from the leg wire to the leg wire and from the leg wire to the tube shell, and does not explode.

3.2. Under the conditions that the capacitance is 2000pF, the series resistance is 5000 omega and the charging voltage is 8KV, the leg wire-leg wire and the leg wire-tube shell of the electronic detonator are discharged, and the electronic detonator is not exploded.

When static electricity is generated, tip discharge is carried out by a discharge tooth gap by using 2 4.7K FUSE resistors and combining with a discharge tooth design of a pin wire bonding pad, and the remaining incomplete discharged charges are limited by the 2 4.7K FUSE resistors, so that the pins of a chip are prevented from being damaged.

According to the test results, the intrinsically safe circuit with the FUSE resistor has good direct current resistance, alternating current resistance and static sensitivity.

In other embodiments of the present invention, the current limiting module may also use both the current limiting resistor and the FUSE resistor.

The intrinsic safety circuit for the electronic detonator can be used as an interface circuit, is additionally arranged in the electronic detonator, can be used as a general scheme of a two-wire electronic detonator communication protocol, and has the advantages of small volume and strong transportability.

Referring to fig. 4, in an embodiment of the present invention, there is further provided a delay device for an electronic detonator, including a detonator leg wire 100, where the detonator leg wire 100 is connected to the intrinsically safe circuit 200 and then connected to a control terminal, and the control terminal includes:

the signal input end of the delay control chip 300 is connected with the output end of the intrinsic safety circuit 200;

the input end of the energy storage module 400 is connected with the output end of the intrinsic safety circuit 200, and the output end of the energy storage module 400 is connected with the ignition switch 500;

the ignition switch 500, the ignition switch 500 is connected with the signal output end of the delay control chip 300;

the ignition element 600, the ignition element 600 is connected with the ignition switch 500, and the ignition element 600 is used for igniting the ignition charge head.

In one embodiment of the invention, the delay control chip adopts an ASIC chip, has the function of delay counting, mainly comprises a signal receiving module, a data sending module, an instruction decoding module, a storage module, a delay counter, a clock circuit and an output driving module, can receive signals from a detonator pin wire, and outputs control signals to an ignition switch after delay counting; the energy storage module adopts an energy storage capacitor, the ignition element is one of an ignition resistor or a rigid explosive head, and the ignition switch is one of an MOS (metal oxide semiconductor) tube, a triode or a field effect transistor.

In an embodiment of the present invention, the control terminal further includes a chip protection circuit 700, the chip protection circuit includes a protection resistor, the protection resistor is disposed at the voltage input terminal and the signal output terminal of the delay control chip 600, the protection resistor is used for protecting the delay control chip, and can enhance the protection of the electronic detonator delay module, thereby effectively preventing the electronic detonator delay module from being damaged by blasting impact and extrusion during blasting, and preventing the electronic detonator from being misfired.

The intrinsic safety circuit can be used as a two-wire system communication protocol interface circuit, the two detonator leg wires are not only signal transmission ports, but also chip working energy supply ports, the capacitors of the energy storage module can be charged through the detonator leg wires, electric energy is input into the capacitors of the energy storage module through the detonator leg wires, the electric energy can be stored through the capacitors of the energy storage module, and the electric energy can be provided for the control chip through the capacitors of the energy storage module after power failure, so that abnormal detonation caused by insufficient starting power is avoided;

when charging, the current limiting module of the intrinsically safe circuit can play a role of limiting the input of a detonator pin wire, the transient suppression module can perform anti-surge pulse, the rectifying module of the intrinsically safe circuit can perform alternating current-direct current conversion and output direct current to charge a capacitor of the energy storage module, the blocking circuit of the intrinsically safe circuit can prevent the energy of the capacitor from being reversely filled back to the pin wire when the circuit is in fault, if the power supply pin of the time delay control chip 600 is in short circuit with the first signal input end, the blocking diode D5 and the diode D4 of the rectifying circuit form a two-stage blocking diode, when the power supply pin of the time delay control chip 600 is in short circuit with the second signal input end, the blocking diode D6 and the diode D3 of the rectifying circuit form a two-stage blocking diode, and in addition, the blocking diode D5 and the blocking diode D6 can convert nonpolarity into polarity.

The electronic detonator product adopting the intrinsic safety circuit and the time delay device can achieve the purpose of intrinsic safety, prevent the capacitive energy from being back-filled to the pin wire end when the circuit fails, and solve the problem that the common electronic detonator is easy to generate gas and coal dust explosion under the coal mine operation. The product has strong practicability, is simple and convenient and is easy to popularize.

It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

Furthermore, it should be understood that although the present description refers to embodiments, not every embodiment may contain only a single embodiment, and such description is for clarity only, and those skilled in the art should integrate the description, and the embodiments may be combined as appropriate to form other embodiments understood by those skilled in the art.