Method for electronic detonator to resist electromagnetic interference

Abstract

The present invention discloses a method for resisting electromagnetic interference of electronic detonators. During small-section blasting, electromagnetic interference can easily cause the electronic detonators to mis-detonate or fail to detonate. The method of the present invention adds a level output pin g to the control chip. Pin g outputs a low level after the control chip is powered on and reset, and outputs a high level after the control chip receives a detonation command; an NMOS transistor and an anti-backflow diode are added; pin g is connected to the gate of the NMOS transistor, the drain of the NMOS transistor is connected to the anode of the anti-backflow diode, the cathode of the anti-backflow diode is connected to the power supply terminal of the control chip, and the source of the NMOS transistor is connected to the ground terminal of the rectifier bridge. When an electronic detonator is detonated, a current pulse generated by electromagnetic interference caused by the explosion is induced on the pin line of the subsequent electronic detonator. The current pulse is directly transmitted to the ground, and the control chip will not be interfered with by the electromagnetic pulse caused by the explosion. The method of the present invention is easy to implement and has a good anti-electromagnetic pulse interference effect.

Description

Technical Field

[0001] The present invention belongs to the technical field of electronic detonators and relates to a method for anti-electromagnetic interference of electronic detonators. Background Art

[0002] Compared with non-electric detonators, electronic detonators have functions such as more accurate initiation delay time control, initiation energy control, and safety control, and are widely used. Since electronic detonators are involved in blasting operations, their safety requirements are extremely high. It is required that electronic detonators can not be accidentally detonated under electromagnetic interference and misoperation in complex environments. Especially during small-section blasting, the induced voltage and induced current of electronic detonators are likely to cause accidental detonation and misfire of electronic detonators.

[0003] A small section generally refers to a tunnel with a width or span of the cross-sectional outer contour less than 4m and an area less than 20m 2 . When using the mining method for construction, various pilot tunnels, various municipal tunnels, water supply and drainage pipelines, pedestrian tunnels, etc. belong to this type. The vibration and strong electromagnetic interference intensity generated by blast holes are inversely proportional to the square of the distance. Due to the relatively short hole spacing in small-section tunneling blasting, the vibration and strong electromagnetic interference generated by the previously detonated blast holes have a strong impact, resulting in damage and failure of the chips of the electronic detonators that are in the process of delay blasting, and causing abnormal blasting. The current method to alleviate this situation is to reduce the delay between electronic detonators and reduce the impact of the blasting generated by the previously detonated blast holes on the chips of the electronic detonators in the unblasted blast holes. This restricts the blasting plan, affects the efficiency and effect of blasting, and increases the construction period and construction cost. Summary of the Invention

[0004] The purpose of the present invention is to provide a method for anti-electromagnetic interference of electronic detonators aiming at the problems existing in the existing electronic detonators.

[0005] The power supply terminal of the control chip U of the electronic detonator and one end of the voltage stabilizing capacitor C are connected to the power output terminal of the rectifier bridge. The other end of the voltage stabilizing capacitor C and the grounding terminal of the control chip U are connected to the grounding terminal of the rectifier bridge, forming a parasitic capacitance Cp with the ground; the rectifier bridge includes four diodes. The cathode of the first diode D1 is connected to the anode of the second diode D2 and then connected to one end of the step-down resistor R. The other end of the step-down resistor R is connected to a lead wire P of the electronic detonator. The anode of the third diode D3 is connected to the cathode of the fourth diode D4 and then connected to another lead wire N of the electronic detonator. The anode of the first diode D1 and the anode of the fourth diode D4 are connected as the grounding terminal of the rectifier bridge. The cathode of the second diode D2 and the cathode of the third diode D3 are connected as the power output terminal of the rectifier bridge. In the method of the present invention, a level output pin g is added to the control chip U. The level output pin g outputs a low level after the control chip U is powered on and reset, and outputs a high level after the control chip U receives the detonation command; an Nmos transistor and an anti-backflow diode D are added. The level output pin g is connected to the gate of the Nmos transistor N. The drain of the Nmos transistor N is connected to the anode of the anti-backflow diode D. The cathode of the anti-backflow diode D is connected to the power supply terminal of the control chip U. The source of the Nmos transistor N is connected to the grounding terminal of the rectifier bridge.

[0006] After the control chips U of multiple parallel-connected electronic detonators are powered on and reset, the pin g outputs a low level, the Nmos transistor N is turned off, and the detonator actively cuts off the power after sending the detonation command; after the control chip U receives the detonation command, the pin g outputs a high level, the Nmos transistor N is turned on, and the power output terminal and the grounding terminal of the rectifier bridge are connected; the control chips U of all the electronic detonators rely on the power of the voltage stabilizing capacitor C for delayed detonation.

[0007] When an electronic detonator detonates, the explosion of the explosive causes electromagnetic interference and generates a current pulse. A current pulse is induced on the lead wire of the subsequent detonating electronic detonator. The current pulse does not flow through the control chip U and is directly transmitted to the ground, and the control chip U is not interfered by the electromagnetic pulse caused by the explosion.

[0008] Since the impedance of the control chip U is much larger than the on-impedance of the Nmos transistor N, if a current pulse is induced on one lead wire P of the subsequent detonating electronic detonator, the current pulse is transmitted to the ground through the step-down resistor R, the second diode D2, the Nmos transistor N, and the parasitic capacitance Cp; if a current pulse is induced on the other lead wire N of the subsequent detonating electronic detonator, the current pulse is transmitted to the ground through the third diode D3, the Nmos transistor N, and the parasitic capacitance Cp.

[0009] Furthermore, a fuse F is also provided. The power supply terminal of the control chip U is connected to the cathode of the anti-backflow diode D and then connected to the power output terminal of the rectifier bridge through the fuse F.

[0010] After the control chip U of multiple electronically detonators connected in parallel is powered on and reset, the pin g outputs a low level, the Nmos transistor N is turned off, and the initiator actively cuts off the power after sending out the initiation command; after receiving the initiation command, the pin g of the control chip U outputs a high level, the Nmos transistor N is turned on, the power output terminal and the ground terminal of the rectifier bridge are connected, causing a short circuit, and the fuse F blows; the control chips U of all the electronically detonators rely on the power of the voltage stabilizing capacitor C for delayed initiation.

[0011] When an electronically detonator initiates, the explosion of the explosive causes electromagnetic interference to generate current pulses, and current pulses are induced on the lead wires of the later-initiated electronically detonators. The current pulses do not flow through the control chip U and are directly transmitted to the ground, and the control chip U is not interfered by the electromagnetic pulses caused by the explosion.

[0012] If a current pulse is induced on a lead wire P of a later-initiated electronically detonator, the current pulse causes the voltage of the first diode D1 of the later-initiated electronically detonator to exceed the reverse breakdown voltage, and the first diode D1 breaks down and conducts. The current pulse induced on the lead wire P is transmitted to the ground through the step-down resistor R, the first diode D1, and the parasitic capacitor Cp;

[0013] If a current pulse is induced on the other lead wire N of the later-initiated electronically detonator, the current pulse causes the voltage of the fourth diode D4 of the later-initiated electronically detonator to exceed the reverse breakdown voltage, and the fourth diode D4 breaks down and conducts. The current pulse induced on the lead wire N is transmitted to the ground through the fourth diode D4 and the parasitic capacitor Cp.

[0014] When the first electronically detonator with delayed initiation is about to initiate, there are no induced current pulses on the lead wire P and the lead wire N. The power of the voltage stabilizing capacitor C is used for the delayed initiation of the electronically detonator, and this electronically detonator initiates normally.

[0015] After receiving the initiation command, the Nmos transistor is in the conducting state in the method of the present invention. When an electronically detonator initiates, the explosion of the explosive causes electromagnetic interference to generate current pulses, and current pulses are induced on the lead wires of the later-initiated electronically detonators. The current pulses do not flow through the control chip and are directly transmitted to the ground, realizing that the control chip is not interfered by the electromagnetic pulses caused by the explosion. The method of the present invention is easy to implement and has a good anti-electromagnetic pulse interference effect. Description of the Drawings

[0016] Figure 1 It is a control schematic diagram of an existing electronically detonator;

[0017] Figure 2 It is a schematic diagram of the implementation of an embodiment of the method of the present invention;

[0018] Figure 3 It is a schematic diagram of the implementation of another embodiment of the method of the present invention. Detailed Implementation Manner

[0019] The present invention will be further described below in conjunction with the accompanying drawings and embodiments. The following embodiments are only specific embodiments of the present invention, but the design concept of the present invention is not limited thereto. Any non-substantive modification made to the present invention using this concept shall fall within the protection scope of the present invention.

[0020] As Figure 1 shown, for the existing control chip U' of the electronic detonator, the signal input end and one end of the voltage stabilizing capacitor C are connected to the output end of the rectifier bridge, and the other end of the voltage stabilizing capacitor C and the grounding end of the control chip U' are connected to the grounding end of the rectifier bridge, forming a parasitic capacitance Cp with the ground; one input end of the rectifier bridge is connected to the step-down resistor R and then used as a lead wire of the electronic detonator, and the other input end of the rectifier bridge is used as another lead wire of the electronic detonator. The two lead wires are connected to the initiator, and the initiator sends an initiation signal and supplies power to the control device. The control chip U' in the control device initiates according to the initiation signal sent by the lead wire.

[0021] Embodiment 1.

[0022] As Figure 2 shown, for the method for the electronic detonator to resist electromagnetic interference, an additional level output pin g is added to the control chip U of the original electronic detonator. The level output pin g outputs a low level after the control chip U is powered on and reset, and outputs a high level after the control chip U receives the initiation command. An additional Nmos transistor and an anti-backflow diode D are added.

[0023] The power output end of the rectifier bridge is connected to the drain of the Nmos transistor N and the anode of the anti-backflow diode D. The power supply end of the control chip U and one end of the voltage stabilizing capacitor C are connected to the cathode of the anti-backflow diode D. The level output pin g of the control chip U is connected to the gate of the Nmos transistor N. The source of the Nmos transistor N, the other end of the voltage stabilizing capacitor C, and the grounding end of the control chip U are connected to the grounding end of the rectifier bridge and form a parasitic capacitance Cp with the ground.

[0024] Among them, the rectifier bridge includes four diodes. The cathode of the first diode D1 is connected to the anode of the second diode D2 and then connected to one end of the step-down resistor R. The other end of the step-down resistor R is connected to a lead wire P of the electronic detonator. The anode of the third diode D3 is connected to the cathode of the fourth diode D4 and then connected to another lead wire N of the electronic detonator. The anode of the first diode D1 and the anode of the fourth diode D4 are connected as the grounding end of the rectifier bridge. The cathode of the second diode D2 and the cathode of the third diode D3 are connected as the power output end of the rectifier bridge.

[0025] After the control chip U of multiple parallel electronic detonators is powered on and reset, the pin g outputs a low level, the Nmos transistor N is turned off, and the initiator actively cuts off power after sending out an initiation command; after the control chip U receives the initiation command sent by the initiator, the pin g outputs a high level, the Nmos transistor N is turned on, and the power output terminal and the ground terminal of the rectifier bridge are connected; the control chips U of all the electronic detonators rely on the power of the voltage stabilizing capacitor C for delayed initiation.

[0026] When an electronic detonator detonates, the explosion of the explosive causes electromagnetic interference to generate current pulses, and current pulses are induced on the lead wires of the later-detonating electronic detonators. The current pulses do not flow through the control chip U and are directly transmitted to the ground, and the control chip U is not interfered by the electromagnetic pulses caused by the explosion. Specifically:

[0027] Since the impedance of the control chip U is much greater than the on-impedance of the Nmos transistor N, if a current pulse is induced on a lead wire P of the later-detonating electronic detonator, the current pulse is transmitted to the ground through the step-down resistor R, the second diode D2, the Nmos transistor N, and the parasitic capacitor Cp; if a current pulse is induced on the other lead wire N of the later-detonating electronic detonator, the current pulse is transmitted to the ground through the third diode D3, the Nmos transistor N, and the parasitic capacitor Cp.

[0028] When the first electronically detonated detonator is about to detonate, there are no induced current pulses on the lead wire P and the lead wire N. The power of the voltage stabilizing capacitor C is used for the delayed initiation of the electronic detonator, so the electronic detonator detonates normally.

[0029] Embodiment 2.

[0030] As Figure 3 shown, a fuse F is additionally provided on the basis of Embodiment 1. One end of the fuse F is connected to the power supply terminal of the control chip U after being connected to the cathode of the anti-backflow diode D, and the other end of the fuse F is connected to the power output terminal of the rectifier bridge.

[0031] After the control chip U of multiple parallel electronic detonators is powered on and reset, the pin g outputs a low level, the Nmos transistor N is turned off, and the initiator actively cuts off power after sending out an initiation command; after the control chip U receives the initiation command, the pin g outputs a high level, the Nmos transistor N is turned on, the power output terminal and the ground terminal of the rectifier bridge are connected, causing a short circuit, and the fuse F blows; the control chips U of all the electronic detonators rely on the power of the voltage stabilizing capacitor C for delayed initiation.

[0032] When an electronic detonator detonates, the explosion of the explosive causes electromagnetic interference to generate current pulses, and current pulses are induced on the lead wires of the later-detonating electronic detonators. The current pulses do not flow through the control chip U and are directly transmitted to the ground, and the control chip U is not interfered by the electromagnetic pulses caused by the explosion. Specifically:

[0033] If a current pulse is induced on a lead wire P of a post-initiation electronic detonator, the current pulse causes the voltage of the first diode D1 of the post-initiation electronic detonator to exceed the reverse breakdown voltage, and the first diode D1 breaks down and conducts. The current pulse induced on the lead wire P is transmitted to the ground through the step-down resistor R, the first diode D1, and the parasitic capacitor Cp; if a current pulse is induced on another lead wire N of the post-initiation electronic detonator, the current pulse causes the voltage of the fourth diode D4 of the post-initiation electronic detonator to exceed the reverse breakdown voltage, and the fourth diode D4 breaks down and conducts. The current pulse induced on the lead wire N is transmitted to the ground through the fourth diode D4 and the parasitic capacitor Cp.

[0034] When the first delay-initiation electronic detonator is ready to initiate, there is no induced current pulse on the lead wire P and the lead wire N. The charge of the voltage-stabilizing capacitor C is used for the electronic detonator to initiate with a delay, without affecting the normal initiation of the electronic detonator.

[0035] The solution of Embodiment 2 is applicable to the case where the current pulse is strong. In this case, if the solution of Embodiment 1 is adopted, there may be a current pulse entering the control chip U to cause interference. Through practice, in general, the solution of Embodiment 1 can achieve anti-electromagnetic interference.

Claims

1. Method for electronic detonator to resist electromagnetic interference, characterized in that: The anti-electromagnetic interference device adopted includes a control chip U, a rectifier bridge, a step-down resistor R, a voltage-stabilizing capacitor C, an anti-backflow diode D, and an Nmos transistor N; The control chip U is provided with a level output pin g. The level output pin g outputs a low level after the control chip U is powered on and reset, and outputs a high level after the control chip U receives a detonation command; The rectifier bridge includes four diodes. The cathode of the first diode D1 is connected to the anode of the second diode D2 and then connected to one end of the step-down resistor R. The other end of the step-down resistor R is connected to a lead wire P of the electronic detonator; the anode of the third diode D3 is connected to the cathode of the fourth diode D4 and then connected to the other lead wire N of the electronic detonator; the anode of the first diode D1 and the anode of the fourth diode D4 are connected as the grounding end of the rectifier bridge; the cathode of the second diode D2 and the cathode of the third diode D3 are connected as the power output end of the rectifier bridge; The power output end of the rectifier bridge is connected to the drain of the Nmos transistor N and the anode of the anti-backflow diode D. The power supply end of the control chip U and one end of the voltage-stabilizing capacitor C are connected to the cathode of the anti-backflow diode D. The level output pin g of the control chip U is connected to the gate of the Nmos transistor N. The source of the Nmos transistor N, the other end of the voltage-stabilizing capacitor C, and the grounding end of the control chip U are connected to the grounding end of the rectifier bridge and form a parasitic capacitor Cp with the ground; When the first delay-detonating electronic detonator is about to detonate, there is no induced current pulse on the lead wires P and N. The electric quantity of the voltage-stabilizing capacitor C is used for the delay detonation of the electronic detonator, and the first delay-detonating electronic detonator detonates normally; After the control chips U of multiple parallel-connected electronic detonators are powered on and reset, the pin g outputs a low level, the Nmos transistor N is turned off, and the detonator actively cuts off the power after sending out a detonation command; after the control chip U receives the detonation command, the pin g outputs a high level, the Nmos transistor N is turned on, and the power output end and the grounding end of the rectifier bridge are connected; the control chips U of all the electronic detonators rely on the electric quantity of the voltage-stabilizing capacitor C for delay detonation; When an electronic detonator detonates, the explosion of the explosive causes electromagnetic interference and generates a current pulse. A current pulse is induced on the lead wire of the later-detonating electronic detonator. The current pulse does not flow through the control chip U and is directly transmitted to the ground, and the control chip U is not interfered by the electromagnetic pulse caused by the explosion; If a current pulse is induced on one lead wire P of the later-detonating electronic detonator, the current pulse is transmitted to the ground through the step-down resistor R, the second diode D2, the Nmos transistor N, and the parasitic capacitor Cp; if a current pulse is induced on the other lead wire N of the later-detonating electronic detonator, the current pulse is transmitted to the ground through the third diode D3, the Nmos transistor N, and the parasitic capacitor Cp.

2. The method for an electronic detonator to resist electromagnetic interference according to claim 1, characterized in that: A fuse F is also provided; the power supply end of the control chip U is connected to the cathode of the anti-backflow diode D and then connected to the power output end of the rectifier bridge through the fuse F.

3. The method for electromagnetic interference resistance of electronic detonators according to claim 2, wherein: After the control chip U of multiple electronically detonators connected in parallel is powered on and reset, the pin g outputs a low level, the Nmos transistor N is turned off, and the detonator actively cuts off the power after sending out a detonation command; after receiving the detonation command, the pin g of the control chip U outputs a high level, the Nmos transistor N is turned on, the power output terminal and the ground terminal of the rectifier bridge are connected, causing a short circuit, and the fuse F melts; the control chips U of all the electronically detonators delay detonation relying on the power of the voltage stabilizing capacitor C. When an electronically detonator detonates, the explosion of the explosive causes electromagnetic interference to generate current pulses, and current pulses are induced on the lead wires of the subsequently detonated electronically detonator. The current pulses do not flow through the control chip U and are directly transmitted to the ground, and the control chip U is not interfered by the electromagnetic pulses caused by the explosion.

4. The method for anti-electromagnetic interference of an electronically detonator according to claim 3, wherein: If a current pulse is induced on a lead wire P of the subsequently detonated electronically detonator, the current pulse causes the voltage of the first diode D1 of the subsequently detonated electronically detonator to exceed the reverse breakdown voltage, the first diode D1 breaks down and conducts, and the current pulse induced on the lead wire P is transmitted to the ground through the step-down resistor R, the first diode D1 and the parasitic capacitor Cp; If a current pulse is induced on another lead wire N of the subsequently detonated electronically detonator, the current pulse causes the voltage of the fourth diode D4 of the subsequently detonated electronically detonator to exceed the reverse breakdown voltage, the fourth diode D4 breaks down and conducts, and the current pulse induced on the lead wire N is transmitted to the ground through the fourth diode D4 and the parasitic capacitor Cp.

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