Explosive bolt driving circuit based on solid-state relay
By designing series and parallel branches and optimizing the energy discharge resistor, the output capacitance and leakage current problems of solid-state relays in the explosion bolt drive circuit are solved, realizing a miniaturized, lightweight, and highly reliable explosion bolt drive circuit suitable for shock and vibration environments.
Patent Information
- Application Number
- CN202422893342.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-26
- Publication Date
- 2025-10-28
- Estimated Expiration
- 2034-11-26
AI Technical Summary
In existing explosion bolt drive circuits, solid-state relays have output capacitance and leakage current issues, which increases the risk of false triggering in high-temperature environments. In addition, they are bulky and unsuitable for applications with limited space or strict quality requirements.
By adopting a series and parallel branch design, combined with energy discharge resistors, electrostatic discharge resistors and protection modules, the output capacitance and leakage current of the solid-state relay are optimized. By designing a 3-level solid-state relay switch, a 2-level energy discharge resistor and a current limiting protection circuit, the impact of voltage step jumps and leakage current is reduced.
This invention achieves miniaturization and weight reduction of solid-state relay drive circuits, improves shock and vibration resistance, reduces the risk of false triggering, and is suitable for environments with strong shock and vibration.
Smart Images
Figure CN223485010U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of pyrotechnic drive circuit technology, specifically to an explosion bolt drive circuit based on a solid-state relay. Background Technology
[0002] In existing technologies, the driving circuits for pyrotechnic devices such as explosive bolts mainly use electromagnetic relays. However, electromagnetic relays are prone to malfunction under impact and vibration. Solid-state relays, on the other hand, use semiconductor power devices as switching elements. They have no moving parts, no mechanical contacts, and generate no electrical sparks, exhibiting excellent resistance to impact and vibration. This effectively solves the problem of malfunction caused by mechanical vibration and impact when electromagnetic relays are used to drive pyrotechnic devices such as explosive bolts. Furthermore, for the same driving current and voltage, solid-state relays are often smaller and lighter than electromagnetic relays, making them well-suited for applications with limited space or stringent quality requirements.
[0003] However, solid-state relays also have the following problems: (1) Solid-state relays have an output capacitor; (2) Solid-state relays have the characteristic of output leakage current. Because of the output capacitor of the solid-state relay, when the input terminal of the solid-state relay is connected to the power supply, there will be a voltage step jump at the output terminal. Because of the leakage current characteristic of the solid-state relay, there will always be a microampere level leakage current output to the explosion bolt. Especially in high temperature environments, the leakage current of the solid-state relay will increase sharply, reaching up to the milliampere level, which will lead to energy accumulation and cause the explosion bolt to be falsely triggered. Utility Model Content
[0004] The purpose of this invention is to provide an explosion bolt drive circuit based on a solid-state relay, aiming to solve the technical problem of how to make the explosion bolt drive circuit smaller and more impact-resistant.
[0005] To solve the above-mentioned technical problems, the technical solution provided by this utility model is as follows:
[0006] An explosion bolt driving circuit based on a solid-state relay includes:
[0007] power supply;
[0008] The series branch has multiple solid-state relays, and the input terminal of the series branch is connected to the positive terminal of the power supply.
[0009] The parallel branch has multiple energy discharge resistors. The input terminal of each energy discharge resistor is connected to the output terminal of the corresponding solid-state relay, and the output terminal of the energy discharge resistor is connected to the output terminal of the series branch and the negative terminal of the power supply.
[0010] Preferably, the series branch includes a first solid-state relay, a second solid-state relay, and a third solid-state relay;
[0011] The input terminal of the first solid-state relay is connected to the positive terminal of the power supply. The output terminal of the first solid-state relay is connected to the input terminal of the second solid-state relay. The output terminal of the second solid-state relay is connected to the input terminal of the third solid-state relay. The output terminal of the third solid-state relay is connected to the output terminal of the series branch.
[0012] Preferably, the parallel branch includes a first energy discharge resistor and a second energy discharge resistor;
[0013] The input terminal of the first energy discharge resistor is connected to the output terminal of the first solid-state relay, the input terminal of the second energy discharge resistor is connected to the output terminal of the second solid-state relay, and the output terminal of the first energy discharge resistor is connected to the output terminal of the second energy discharge resistor and the output terminal of the series branch.
[0014] Preferably, the parallel branch also includes an electrostatic discharge resistor;
[0015] The input terminal of the electrostatic discharge resistor is connected to the output terminal of the third solid-state relay, and the output terminal of the electrostatic discharge resistor is connected to the output terminal of the series branch.
[0016] Preferably, a current-limiting resistor is connected in series between the output terminal of the third solid-state relay and the output terminal of the series branch.
[0017] Preferably, the parallel branch also includes a protection module, one end of which is connected to the output terminal of the series branch, and the other end is connected to the output terminal of the electrostatic discharge resistor.
[0018] Preferably, the value of the electrostatic discharge resistor is in the range of 1kΩ to 20kΩ, including the endpoint value.
[0019] Preferably, the resistance value of the current-limiting resistor is in the range of 1Ω to 10Ω, including the terminal value.
[0020] Preferably, the protection module includes a diode, a varistor, or a gas discharge tube.
[0021] Compared with the prior art, the beneficial effects of this utility model are as follows: the explosion bolt drive circuit utilizes the characteristics of solid-state relays, such as strong impact resistance, strong vibration capability, fast switching speed, small size, and light weight. The design of parallel energy discharge resistor avoids the influence of solid-state relay output capacitance and leakage current on the explosion bolt, so that the explosion bolt drive circuit can be miniaturized and lightweight, and can also be better applied to strong impact and vibration working environments. Attached Figure Description
[0022] Figure 1 This is a structural block diagram of an explosion bolt drive circuit provided in one embodiment of this application;
[0023] Figure 2 A circuit diagram of an explosion bolt drive circuit provided in one embodiment of this application;
[0024] Figure 3 A circuit diagram of an explosion bolt drive circuit provided for another embodiment of this application. Detailed Implementation
[0025] The following embodiments are further descriptions of the present invention and are not intended to limit the present invention.
[0026] like Figure 1 As shown, an explosion bolt driving circuit based on a solid-state relay includes:
[0027] Power supply 1;
[0028] A series branch has multiple solid-state relays 2, and the input terminal of the series branch is connected to the positive terminal of the power supply 1;
[0029] The parallel branch has multiple energy discharge resistors 3. The input terminal of each energy discharge resistor 3 is connected to the output terminal of the corresponding solid-state relay 2, and the output terminal of the energy discharge resistor 3 is connected to the output terminal of the series branch and the negative terminal of the power supply 1.
[0030] This invention addresses the problem of weak shock and vibration resistance of electromagnetic relays in explosive bolt drive circuits. It selects solid-state relays to realize the switching drive of explosive bolts and improves the output capacitance and leakage current of solid-state relays by using energy discharge resistors. This results in an explosive bolt drive circuit based on solid-state relays that is low in power consumption, small in size, strong in shock and vibration resistance, and highly reliable.
[0031] In one specific embodiment, such as Figure 2 As shown, the series branch includes a first solid-state relay SSR1, a second solid-state relay SSR2, and a third solid-state relay SSR3; the input terminal of the first solid-state relay SSR1 is connected to the positive terminal of the power supply, the output terminal of the first solid-state relay SSR1 is connected to the input terminal of the second solid-state relay SSR2, the output terminal of the second solid-state relay SSR2 is connected to the input terminal of the third solid-state relay SSR3, and the output terminal of the third solid-state relay SSR3 is connected to the output terminal of the series branch.
[0032] The parallel branch includes a first energy discharge resistor R1 and a second energy discharge resistor R2; the input terminal of the first energy discharge resistor R1 is connected to the output terminal of the first solid-state relay SSR1, the input terminal of the second energy discharge resistor R2 is connected to the output terminal of the second solid-state relay SSR2, and the output terminal of the first energy discharge resistor R1 is connected to the output terminal of the second energy discharge resistor R2 and the output terminal of the series branch.
[0033] The parallel branch also includes an electrostatic discharge resistor R3; the input terminal of the electrostatic discharge resistor R3 is connected to the output terminal of the third solid-state relay SSR3, and the output terminal of the electrostatic discharge resistor R3 is connected to the output terminal of the series branch.
[0034] A current-limiting resistor R4 is connected in series between the output terminal of the third solid-state relay SSR3 and the output terminal of the series branch.
[0035] The parallel branch also includes a protection module TVS. One end of the protection module TVS is connected to the output terminal of the series branch, and the other end is connected to the output terminal of the electrostatic discharge resistor R3.
[0036] In one specific embodiment, the electrostatic discharge resistor R3 has a value range of 1kΩ to 20kΩ, including the endpoint value.
[0037] In one specific embodiment, the value of the current-limiting resistor R4 ranges from 1Ω to 10Ω, including the endpoint value.
[0038] In one specific embodiment, the protection module TVS includes a diode, a varistor, or a gas discharge tube.
[0039] like Figure 3 As shown, the output terminal of the series branch, i.e. the output terminal of the current-limiting resistor R4, is connected to the explosion bolt, and the explosion bolt is connected to the negative terminal of the power supply to form a circuit.
[0040] This technical solution comprises a three-stage solid-state relay switch, a two-stage energy discharge resistor, a current-limiting protection circuit, and an electrostatic discharge (ESD) protection circuit. The three-stage solid-state relay switches all utilize 60V PMOS transistors to construct the switching circuit. The first solid-state relay circuit functions as a pre-disarming switch, the second as a disarming switch, and the third as an ignition switch. The current-limiting resistor, with a value ranging from 1Ω to 10Ω, limits the ignition current to a reasonable range and provides overcurrent protection against short circuits in the bridge circuit resistance after detonation of explosive bolts or other inertial pyrotechnic devices, preventing impact on the main power supply and system malfunction. The two-stage energy discharge resistor addresses the effects of output capacitance and leakage current from the solid-state relays. The ESD discharge resistor and the TVS protection module prevent the accumulation of static electricity on the output circuit before the explosive bolt is connected. The TVS protection module can be implemented using a TVS diode such as the SMAJ36A, or a varistor or gas discharge tube. The value of the electrostatic discharge resistor is between 1kΩ and 20kΩ. If the resistor is too small, the power will be too high when the drive circuit is working; if the resistor is too large, the electrostatic discharge effect will be weakened.
[0041] This technical solution designs a two-stage energy discharge resistor. Alternatively, an NMOS power transistor (or an NPN power transistor) can be used to achieve the energy discharge function. The advantage of the NMOS power transistor energy discharge circuit is that the discharge speed is faster, but the control circuit is more complex than that of the energy discharge resistor. It requires the design of control logic to turn off the NMOS power transistor when the solid-state relay is turned on and turn on the NMOS power transistor when the solid-state relay is turned off. The energy discharge resistor has two functions: (1) to limit the voltage step jump caused by the output capacitor of the solid-state relay to a safe range. Designing each stage of energy bleed resistor can reduce the amplitude of the voltage step change to 10% of the original value. Then, two stages of energy bleed resistor can reduce the amplitude of the voltage step change to 1% of the original value. For a 28V working power supply environment, the voltage step change at the moment of power-on can be reduced to below 0.28V. At the same time, the energy bleed resistor can also reduce the time width of the voltage step change pulse by more than 10 times. In actual measurement, it can be controlled within 50 microseconds. In this way, the total energy of the voltage step change will be far less than the energy that the bridge circuit resistor of the explosion bolt can withstand, thus solving the influence of the output capacitor of the solid-state relay. (2) Limit the output voltage caused by the leakage current of the solid-state relay to below 10mV. The leakage current of solid-state relays is in the microampere range at room temperature and can reach the milliampere range at high temperatures. The maximum leakage current is generally ≤5mA at 125℃. Assuming the first energy discharge resistor is designed to be a 500Ω resistor, the 1mA current load of the first stage is the 500Ω resistor and the second solid-state relay. However, the equivalent resistance of the second solid-state relay when it is not turned on is above the megaΩ level. Therefore, the current of the 1mA leakage current of the first stage solid-state relay that is distributed to the second solid-state relay will be much smaller than the current distributed to the 500Ω energy discharge resistor. Similarly, the second energy discharge resistor can limit the leakage current of the third solid-state relay to an even smaller level, thereby solving the problem of excessive leakage current of solid-state relays leading to the accumulation of energy in the bridge circuit resistor of the exploding bolt, which in turn causes false triggering.
[0042] The above detailed description is a specific description of feasible embodiments of the present utility model. The above embodiments are not intended to limit the patent scope of the present utility model. All equivalent implementations or modifications that do not depart from the present utility model should be included in the patent scope of this case.
Claims
1. An explosion bolt driving circuit based on a solid-state relay, characterized in that, include: power supply; A series branch has multiple solid-state relays, and the input terminal of the series branch is connected to the positive terminal of the power supply; The parallel branch has multiple energy discharge resistors, the input terminal of each energy discharge resistor is connected to the output terminal of the corresponding solid-state relay, and the output terminal of the energy discharge resistor is connected to the output terminal of the series branch and the negative terminal of the power supply.
2. The explosion bolt driving circuit based on a solid-state relay according to claim 1, characterized in that, The series branch includes a first solid-state relay, a second solid-state relay, and a third solid-state relay; The input terminal of the first solid-state relay is connected to the positive terminal of the power supply. The output terminal of the first solid-state relay is connected to the input terminal of the second solid-state relay. The output terminal of the second solid-state relay is connected to the input terminal of the third solid-state relay. The output terminal of the third solid-state relay is connected to the output terminal of the series branch.
3. The explosion bolt driving circuit based on a solid-state relay according to claim 2, characterized in that, The parallel branch includes a first energy discharge resistor and a second energy discharge resistor; The input terminal of the first energy discharge resistor is connected to the output terminal of the first solid-state relay, the input terminal of the second energy discharge resistor is connected to the output terminal of the second solid-state relay, and the output terminal of the first energy discharge resistor is connected to the output terminal of the second energy discharge resistor and the output terminal of the series branch.
4. The explosion bolt driving circuit based on a solid-state relay according to claim 3, characterized in that, The parallel branch also includes an electrostatic discharge resistor; The input terminal of the electrostatic discharge resistor is connected to the output terminal of the third solid-state relay, and the output terminal of the electrostatic discharge resistor is connected to the output terminal of the series branch.
5. The explosion bolt driving circuit based on a solid-state relay according to claim 4, characterized in that, A current-limiting resistor is connected in series between the output terminal of the third solid-state relay and the output terminal of the series branch.
6. The explosion bolt driving circuit based on a solid-state relay according to claim 4, characterized in that, The parallel branch also includes a protection module, one end of which is connected to the output terminal of the series branch, and the other end is connected to the output terminal of the electrostatic discharge resistor.
7. The explosion bolt driving circuit based on a solid-state relay according to claim 4, characterized in that, The value of the electrostatic discharge resistor is in the range of 1kΩ to 20kΩ, including the endpoint value.
8. The explosion bolt driving circuit based on a solid-state relay according to claim 5, characterized in that, The resistance value of the current-limiting resistor ranges from 1Ω to 10Ω, including the endpoint value.
9. The explosion bolt driving circuit based on a solid-state relay according to claim 6, characterized in that, The protection module includes a diode, a varistor, or a gas discharge tube.