Series-connection current limiting circuit of miner lamp intrinsic safety power supply

An intrinsically safe, current-limiting circuit technology, which is applied in the direction of electric lamp circuit layout, electric light source, light source, etc., can solve the problems of large size of miner's lamp, high cost of battery, and large fault current of the circuit

CN102695316BInactive Publication Date: 2014-03-19FUSHUN MINERS LAMP MFG GENERAL PLANT
4 Cites 0 Cited by

Patent Information

Authority / Receiving Office
CN · China
Patent Type
Patents(China)
Current Assignee / Owner
Publication Date
2014-03-19
Estimated Expiration
Not applicable · inactive patent

Smart Images

  • Figure 1
    Figure 1
  • Figure 2
    Figure 2
Patent Text Reader

Abstract

The invention discloses a series-connection current limiting circuit of a miner lamp intrinsic safety power supply. The series-connection current limiting circuit of the miner lamp intrinsic safety power supply is characterized by comprising a DC / DC (Direct Current / Direct Current) boosted circuit, a control circuit, a reference power supply, a current sampling circuit, a voltage sampling circuit and a three-stage series-connection power adjusting and protecting circuit, wherein the DC / DC boosted circuit is formed by an IC1 (Integrated Circuit), diodes, capacitors and a resistor and is used for supplying a control power supply; the control circuit is formed by an IC2 and resistors and used for setting and comparing the voltage and the current; the reference power supply is formed by an IC3, a resistor and a capacitor and is used for supplying the preset control voltage for a '+' input end of the IC2; the current sampling circuit is formed by a resistor R1 and a resistor R2, and the voltage sampling circuit is formed by a resistor R12 and a resistor R13, and the current sampling circuit and the voltage sampling circuit are respectively used for supplying the preset control voltage for a '-' input end of the IC2; and the three-stage series-connection power adjusting and protecting circuit is formed by an FET2 (Field Effect Transistor), an FET3 and an FET4. According to the series-connection current limiting circuit of the miner lamp intrinsic safety power supply, disclosed by the invention, the current limiting circuit is formed by applying power semiconductor devices and other electronic devices, and the situations that when in normal work, the inner resistances of the devices are kept to the lowest, and no influence on the working performance of loads is realized; and the inner resistances of the devices can be increased immediately when the loads are in over current or short circuit failure, the failure current can be immediately limited within the safety current, and thus the miner lamp power supply can be safely protected.
Need to check novelty before this filing date? Find Prior Art

Description

1. Technical field

[0001] The invention belongs to the special safety technology for miner's lamps, and in particular relates to a series current-limiting circuit for safety protection of the miner's lamp power supply. 2. Background technology

[0002] At present, my country's miner's lamp uses a miner's lamp protector to protect the miner's lamp from short-circuit or over-current faults during use. Cut off the fault current, and the protection effect is outstanding; when the battery is discharged to the second half, the internal resistance of the power circuit is large, the fault current is small, or the fault short-circuit point is falsely connected, the protection effect is limited, or even cannot play a protective effect. How to eliminate safety hazards, limit the fault current below the safe current, and make the miner's lamp power supply meet the intrinsically safe standard is an important issue in the miner's lamp design. Intrinsically safe miner's lamp is designed to...

Examples

Embodiment Construction

[0016] The circuit of the present invention is composed of power field effect transistors FET1, FET2, FET3, FET4, integrated circuits IC1, IC2, IC3 and resistance-capacitance elements.

[0017] The integrated circuit IC1 is a 555 time base circuit, packaged with 8 pins, 1 pin is grounded, 2 pins and 6 pins are connected to capacitor C5 and resistor R3, 3 pins are connected to the other end of capacitors C1, C3 and R3, 4 pins, After the 8-pin is connected, it is connected to the external power supply A+, and the 5-pin is vacant.

[0018] The integrated circuit IC2 is a 339 four-voltage comparator, packaged with 14 pins, its 1 pin is connected to the control pole of the field effect transistor FET2, the 2 pins are respectively connected to the control poles of the field effect transistor FET3 and FET4, the 3 pin is connected to the positive pole of the working power supply, and 4 Pin and pin 6 are connected to the current sampling resistor R2, pin 5 and pin 7 are respectively co...