Analysis of the circuit principle of hand-cranked self-generating flashlight

The hand-cranked self-generating flashlight introduced in this article can solve the problem of power outage.

The circuit principle of the hand-cranked self-generating flashlight is shown in Figure 1. Its structural diagram is shown in Figure 2. When using the flashlight, shake the flashlight to make its magnet 7 move up and down , and generate electric energy through coil 6 , which is then rectified by D1-D4 in Figure 2, and C1 stores energy to charge the battery CR2032. Through the switch control, the white light emitting diode emits light to realize the function of self-generating.

In Figure 1, 1 is a cylindrical plastic frame; 2 is a white light emitting diode; 3 is a circuit board; 4 is a switch made of copper sheet; 5 is a reserved position for CR2032 battery; 6 is an air-core coil with an inductance of about 33mh and a wire diameter of about φ.2mm; 7 is a strong magnet that should be able to move up and down smoothly in the cylinder. 8 is a focusing lens with a rubber sealing ring between it and the plastic frame to make the light more concentrated and the range longer; 9 is a rubber shock-absorbing ring to prevent the magnet from directly impacting the plastic frame. Put the above materials as a whole and then put them into the plastic flashlight shell 10 on the right. The slide switch 11 of the flashlight corresponds to the copper sheet of the circuit board, and then screw on the flashlight cover 12. This flashlight can be used.

We can shake this flashlight up and down. It can emit light continuously. Because it uses ultra- bright white light diodes and has lenses for focusing, the brightness and range are greater than the AA battery flashlight that only uses focusing diodes. But this flashlight also has a significant disadvantage, which is that it needs to be shaken continuously to emit light continuously. In order to overcome this disadvantage and save costs, we did not use lithium rechargeable batteries to increase energy storage . Instead, we connected two CR2032 lithium batteries in parallel at both ends of C1. Practice has proved that since the power consumption of this flashlight is about 30mA, the new battery can be used for a long time, and when the power is low, shaking the flashlight can be used for a while. After repeated repeated failures of the battery, it can still continue to work after removing the battery. If your financial conditions permit, it is ideal to replace the battery with a lithium rechargeable battery.