Dynamo Powered Headlight Diagram.
The headlight layout is completely independent from the first part of the project. It consists of two relay coils and a headlight.
DIY contactless dynamo
This page contains instructions for assembling a simple non-contact dynamo machine from relay coils and hard drive magnets with your own hands. A homemade dynamo can power the rear flasher and headlight. If you are interested in a pedal generator for powering equipment, then see a series of articles about assembling a powerful electric generator with your own hands from a car dynamo and a bicycle.
The electrical circuit for powering the rear flasher is quite simple. It contains only three bright red LEDs and a 4700nF capacitor. The capacitor is only used to stabilize the voltage across one of the LEDs. The other two LEDs flicker as the magnets pass near the winding. If you want all three LEDs to blink, you can remove the capacitor. If several LEDs are connected in parallel, the non-flickering LED will continue to light even during a stop.
In the second part of the tutorial, we will create a circuit to power the five bright white LEDs of the headlight using two coils. This circuit is completely independent from the first power supply circuit for the rear light.
- Front headlight with five white LEDs
- Rear light with three red LEDs and 4700nF capacitor
- Coil of the second circuit feeding the headlight
- Coil of the first circuit feeding the tail light
- Hard drive magnet
- Hard disk magnet
- Relay coil
On an oscilloscope, you can trace the voltage generated by the coil. The recorded signal can be imported into a circuit simulator and try to simulate your design.
In the simulation, unfortunately, I did not succeed in achieving constant conductivity for LED 3, despite the fact that I did it on a real circuit. Perhaps this happened due to the lack of inductors in the coil model.
Note that the circuit is not symmetrical as the energy generated by the coil is concentrated on positive values. Energy distribution depends on magnet design and coil used.
- Original system with batteries no longer needed
We will need a cheap LED tail light to fit our new system.
In order not to waste time assembling the coil with your own hands, it is better to try to find some old relay. I took the panel in the picture above from the old mini-automatic telephone exchange. The second picture shows a coil from a disassembled relay.
The coil resistance should be between 100 and 200 ohms. The resistance of the coil shown in the figure is 200 ohms. The higher the resistance of the coil, the more energy is generated, but at the same time, the efficiency decreases due to the increase in losses in the coil.
Dynamo rear light circuit.
Next, you will need to get the neodymium magnets from the hard drive. My rear wheel dynamo uses three of these magnets, but you can use a lot more if you can secure them securely.
Homemade Bicycle Generator // Burn Calories and Make Electricity
- Dual power switch from an old computer
- Original schema
- Assembled circuit
This is a circuit for powering five bright LEDs using two coils. They don’t generate energy at the same time. When connected in series, one coil will absorb some of the energy from the other. This does not happen in this scheme.
To make all LEDs flicker, capacitors are not specifically used here. The only place where you can put the capacitor is in parallel with LED 3, since it never receives negative voltage. As a result, you will have one flicker-free LED and four flickering.
The coil resistance should be within 100.200 ohms, but my circuit uses two 600 ohm coils and everything works great for me.
Hub dynamo as an electric motor
A hub dynamo, or hub generator, is a conventional bicycle hub with a built-in magnetic mechanism. During rotation, eddy currents are formed, at the exit from the bushing, mechanical energy is converted into a current with a given strength, voltage and power. On bicycle dynamos, the voltage reaches 6V and the power reaches 1.8-2W.
The invention was patented by the English company Sturmey Archer. Nowadays, production is actively supported by other manufacturing companies. Shimano and Schmidt.
Features of the generator sleeve design:
- fixed armature (winding) on the axis;
- an annular magnet fixed and rotating with the sleeve;
- terminals and double wires;
- high mass.
The bushing electricity source does not use the bike frame as a ground and is isolated from the frame together with the lamps. In a full-wave rectifier, the AC (output) and DC (to headlamp) circuits are completely separated from each other.
how to make a cycle dynamo. cycle generator
Dynamo hubs are heavy, however, lighter magnets of rare earth metals and an aluminum shell made it possible to slightly reduce their weight. In operation, the device has a low resistance to unwinding, and with an increase in the angular velocity, the current frequency increases. This effect smooths out the voltage gain and allows the generator to operate over wide speed ranges.
The headlights with which the hub generator is equipped have a built-in current stabilizer. When connecting another headlight, a separate rectifier is installed in the circuit so as not to burn the electrical appliance. The brightness of the headlamp depends on its requirements for the energy source and, in fact, the output voltage of the bushing. The more the discrepancy to the smaller side (the headlight is more powerful), the dimmer the light. In the opposite situation, the light source will not work.
How to make a generator with your own hands
Now let’s try to make a generator for a bicycle ourselves. We will use a stepper motor as a basis. To power the lighting devices, you will need an engine with the following characteristics:
- rated current. 2.4 A;
- resistance. 1.2 Ohm;
- output voltage. 2.88 V.
The dynamo should be installed near the rear wheel hub. To transfer rotation from the wheel to the handwheel (rubberized wheel) of the motor, a transfer ring is required. You will need flexible plastic tape to create it. Manufacturing:
- Twist the ribbons into a ring, weld the ends.
- Cut out side slots for each wheel spoke. The depth of the slots. ¼ of the thickness of the ring.
- Place the ring on the knitting needles, fill the slots with glue-sealant on the inside of each knitting needle.
When the ring is ready, a stepper motor is screwed onto the free seats to the feathers, and the flywheel is installed over the ring. If there is no free space for the engine, you will need to weld an additional plate with holes on the frame.
The general scheme for creating a generator with your own hands: generator. assembly of an electrical circuit (bridges, resistors, capacitors). connection. installation of headlights.
To assemble the electrical unit for the headlights you will need:
- LEDs 1N4004. 8 pcs (bridge-converter);
- stabilizer LM317T;
- ceramic capacitor with a capacity of 1 μF;
- resistors 240 Ohm and 820 Ohm for the stabilizer;
- a 1W diode and a 110 Ohm resistor to it (0.25 W);
- plastic box where everything will be.
We assemble the components taking into account the following scheme:
DIY electric circuit
- Solder diodes 1N4004 in parallel bridges.
- Solder a capacitor between the positive and negative ends of the circuit.
- Install resistors and voltage regulator.
- Solder the LED (1W) and resistor to the headlamp circuit.
- Connect the headlight to the capacitors through the wires, and then the electrical circuit with the generator on the rear wheel.
- To turn off the lamp even while cycling, in the gap between the capacitors, install a switch that will close and open the circuit.
The case with the electrical circuit is fixed to the bike frame, the wires are fixed with clamps.
At the last stage, the operation of the system is checked: the wheel must freely pass over the wheel and move synchronously with it. With a properly assembled electrical circuit of capacitors, resistors and rectifier bridges, the headlight will turn on. True, at low wheel speeds, its light will flicker.
Bottle bike generator: features, pros and cons
Let’s get acquainted with another source of energy. a bottle or bus converter.
The bottle generator is a closed housing with a rotating rubber roller on the outside, attached to the front fork. The body contains a directly converting device. winding and magnets. The movement of the magnetic field is achieved due to the engagement of the roller with the tire and the direct transfer of mechanical energy from the wheel to it. The higher the driving speed, the stronger the polarity inside the generator and the higher the output voltage.
- the ability to turn off as unnecessary. just move the roller to the side;
- easy to install on any type of bike;
- inexpensive compared to sleeve generators.
- weight bias: weight is about 250 g, bottle is attached on one side;
- low efficiency in wet weather. the roller slides on the tire;
- noise, high friction at speeds;
- tire sidewall wear;
- long adjust the tilt and position.
We should also mention the carriage bicycle generator. Its body is fixed in the area of the pedal assembly. carriage, under the chain stays. The rotation of the magnetic device is set by a roller that meshes with the rear wheel of the bike. The fixation of the roller on the tire is provided by a clamping spring.
Contactless bicycle generator
Bottle and carriage generators generate power by contacting a moving wheel. The hub dynamo is an integral part of the wheel. The contactless generator does not touch the wheel in any way, does not create frictional forces and resistance to rotation. Eddy currents are formed due to the close location of the plane of rotation of the magnetized rim and a strong magnet.
The headlights are built directly into the device, the electricity is transmitted directly through the rectifier bridge. The indisputable advantages of this generator include:
- lack of cables;
- there is no frictional force and resistance from the side of the device;
- low weight of the structure. no more than 60 g.
The devices are mounted in pairs: on the fork. the headlight, on the feather. the rear reflector. In fact, these are independent flashlights, only they do not work from batteries, but through the rotation of wheels in a magnetic field. The luminosity of the lamps is at or higher than that of rechargeable lighting devices.
When the wheel decelerates, the intensity of the eddy currents decreases, the lights should dim, and when the wheel stops, they go out completely. To ensure uniform light and the ability to use the light even in a parking lot, a capacitor (a battery for generating electricity) is provided in the design, which is filled when the bike moves.
A bicycle generator is a device that allows you to receive electricity by rotating the pedals and transfer it to the bicycle lighting or third-party electrical appliances. By design, bicycle generators are divided into several types: sleeve, bottle, carriage and contactless.
The output current and voltage are inextricably linked with the cadence. the speed of movement. The pattern is valid for all types of generators. The bicycle generator supplies alternating current, which is stabilized to direct current by a rectifier bridge. Its role can be played by soldered diode lamps or special devices, for example, a full-wave rectifier.
Build a Bike DIY. Bicycle Dynamo
The electric generator will allow you to get the additional benefit of pedaling. get energy for the lighting of your two-wheeled vehicle completely free of charge when driving on a dark highway or rough terrain. Small and useful, this device requires little or no maintenance and can be assembled on your own.
What are the lanterns?
Bicycle headlights are of various types. They differ in mounting method, lighting quality and charge type.
The flashlight can be powered by conventional AAA batteries, or can be powered by a lithium battery. Nowadays, rechargeable headlights are becoming more and more popular, as they have sufficient lighting power and a long period of operation, and also do not require the constant purchase of spare batteries.
Most headlights are handlebar mounted, but there are alternatives. They can be fork-mounted or even attached to a cyclist’s helmet. Depending on where the headlamp is installed, the characteristics of road illumination when driving change.
Modern bicycle headlights amaze with their variety of choices in terms of power and quality of lighting. Diodes for the manufacture of headlights on a bicycle are often used the most modern, which allows you to bring lighting to a new level. It is no longer a novelty that the road ahead can be illuminated and well visible, just like in the daytime. In addition, different reflector patterns can add enough side lighting to improve side visibility.
Attaching the headlamp to a cyclist’s helmet is a very convenient way to increase the maneuverability of the light beam and expand the illumination diameter according to the required requirements.
Some cycling enthusiasts who are not satisfied with the modern bicycle headlight market prefer to assemble their own bike lantern. Such a headlamp requires some knowledge in the field of electronics, but the process of making a headlamp with your own hands is not too complicated and time consuming.
Headlight dynamo for bike
A dynamo generator for a bicycle with your own hands can be assembled according to video instructions.
A headlight on a bicycle is a necessary attribute for evening and night walks. They are needed both outside the city and on city streets, since even within the city there is not always enough lighting for normal and safe travel on a bike.
When choosing a good headlight for a bicycle, it is necessary to take into account such parameters as the brightness of the lighting, the reliability of the mount and the economy of battery consumption.
Those who like long journeys in places where it is often impossible to charge a flashlight and other electronics once again prefer to install dynamos. A device that allows you not to depend on an outlet and batteries is very easy to do with your own hands, and there will be a lot of benefits from it. it will save you from the rather annoying question of where the headlight can be charged while traveling, and even at night you will be able to move around calmly.
In addition, a dynamo-based lantern can be installed for the city as well. This charging method is preferred by those who do not like to change batteries very often or periodically charge batteries, which tend to sit down very quickly due to the fact that modern headlights on a bicycle have sufficiently powerful LEDs, and often several, which very quickly consume battery power.
The principle of operation of a dynamo machine for a bicycle is that the alternating current generated by the dynamo generator passes through a rectifier and powers the LED in the headlight. In this case, there is a possibility of light flickering at low speeds, but this problem can be easily solved by installing a smoothing capacitor. The headlight on a bike with a dynamo generator will shine with a bright, even light.
There are two types of dynamos that power a bicycle headlight:
- Bottle dynamo machine. It is a small electric generator that is attached to the side wall of the front tire of a bicycle. Such dynamos are quite convenient, have a low cost and can be easily installed with your own hands. The disadvantages of such a device are additional noise and increased resistance during use. In addition, since the principle of operation of such a dynamo consists in direct friction against the wall of the bicycle tire, in this case, this will contribute to the rapid wear of the tire.
- Dynamo hub. It is a dynamo that is embedded in the hub system of a bicycle wheel. Dynamo hubs are considered to be a fairly reliable source of energy, requiring virtually no maintenance, which is why such hubs are very popular among cycling enthusiasts. In addition, they now often come in the original configuration of a touring bike.
There are a large number of circuits for dynamo machines for a bicycle, allowing you to properly configure them and thereby increase the voltage, power and performance at low speeds of these devices.