Do-it-yourself eternal lantern - modern projects, forms, diagrams and drawings for manufacturing (70 photos)

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A mobile phone has long become an important attribute of a modern person.
It is very inconvenient if it suddenly discharges at the most inopportune moment - on the street or even far from civilization. However, you can insure yourself in this case, and the simplest option is a manual charger, with which you can recharge your phone (as well as a tablet or any other gadget) in any situation. Let's look at several similar devices in this post. We will consider products from Aliexpress, since in Russian online stores the range of such devices is small, and if they are sold, then at a noticeably higher price. It’s easy to order goods from Aliexpress; if you haven’t done this yet, you can find out more about this online store in one of the previous posts.

By the way, this post is regularly updated; we check links to products and try to select options that are the most affordable.

1) The simplest and cheapest manual charging

It looks like this. It's a simple box with a generator inside. If you turn the knob, a voltage of about 5 V appears at the output, which is exactly what is needed to charge a mobile phone. A minimum of frills - there is no built-in battery, only an LED indicating that there is voltage at the output. The price of such a device is low - about 150-200 rubles. including delivery. As they say, cheap and cheerful.

Can I use this simple generator to charge my phone? Yes, you can. But let's be honest - it's not very convenient. If you read the reviews, the device is quite flimsy and breaks easily. But its main drawback is that in practice a cheap generator produces a weak current, far from the 600 mA stated in the specifications. You will have to turn the handle for several minutes to charge the phone even a little. In general, you can buy a device only as a last resort.

2) Flashlights with phone charger with mechanical generator and radio

There are quite a lot of such flashlights on Aliexpress now, here are a few options.

A flashlight with a mechanical generator and a radio, there are adapters for charging your phone via a USB cable. Flashlight link.

Flashlight with FM and AM radio, solar panels and 2000 mAh lithium-ion battery. Charging cables included.

Instead of one device, you get several at once: a hand generator, a solar battery, a power bank, a radio and a flashlight. The built-in battery can be recharged in three ways - from a solar battery, a manual generator and an external source using a USB cable. If you turn the generator handle for a minute (making about 150 revolutions during this time), this will be enough for 10 minutes of flashlight operation, 20 minutes of radio operation, or recharge the phone for 10 minutes of conversation. The device is small and can be easily carried in your pocket. Probably, if you need a hand charger to carry with you, this is the best option to buy.

Another flashlight with a larger generator. It has even more functions - a mechanical generator, a solar battery, a built-in battery + the ability to add batteries. There is also a three-band radio, a flashlight and a separate LED “reading” lamp. You can charge phones and other devices via a USB cable. You can buy this item using this link.

3) Large flashlight with phone charger, generator and radio

If the previous flashlight easily fits in your pocket, then this is an option, rather, for a hike or outdoor recreation. Powerful flashlight plus optional LED bulb, AM and FM radio, solar panel, siren and charging port.

What is a dynamo lantern

The dynamo flashlight is different from others in that it does not have batteries. It may have:

• a handle that must be turned to recharge;
• a lever that can be pressed repeatedly to facilitate charging;
• There is another option - just shake the lantern, and an hour of work is guaranteed.

The eternal flashlight can work without a time limit. The service life depends on the durability of the light bulb built into it. Modern dynamo flashlight - LED. It can work for more than ten years continuously due to autonomous charging.

It is also called a Faraday flashlight. The device is quite simple. The lamp has a metal core and a coil. When they interact, an electric current arises. The eternal flashlight is equipped with a Ni-Mh battery. One or more LED lamps are installed in the lantern. If there is one lamp, then it is placed in the center, if there are several, then around the center.

Wood cutter with oak handle

A couple of weeks ago they sent me carbide caps for wood cutters. Very sharp, with a hole for an M6 bolt. I’ve been wanting to make a decent chisel for a long time. Of course, I have them, but I wanted them to be really beautiful, practical, reliable and powerful! I ruined the first eucalyptus handle, began to put it on and split the handle, and decided to make the second one from an oak table leg. Well, in general it’s ready, done. 14 mm rod from the shock absorber strut.

The first version of a eucalyptus handle. I screwed the feather drill to the shock absorber rod, and the cutter was screwed through a lead gasket, I was just afraid of splitting it when tightening.

The handle was sharpened with a cutter that will be installed in this handle

Introduction.

A few words about powerful LEDs and lumens.

The above circuits use only high-power LEDs, which are produced by such manufacturers as Philips-Lumileds, Cree, Seoul Semiconductor. High-power LEDs are rapidly improving. New models of high-power LEDs, which were the most advanced LEDs six months ago, now look dim. An even brighter generation of LEDs may soon appear on the market. Therefore, we cannot recommend a specific LED model. The electronic circuits are independent of the type of LEDs used, as long as they have the typical forward voltage of a white LED.

To calculate the luminous efficiency of the circuits presented on this page, you only need to know the power of the LEDs. The LED specification specifies how many lumens per watt it produces.

To assemble the brightest headlight, you need to pay attention to:

• electronic circuit - the more power it produces, the better;
• LEDs - the more lumens per watt, the better;
• optics, reflectors, lenses - their efficiency should tend to 100%.

Circuit 1 is the simplest LED headlight power circuit.

A dynamo, a bridge rectifier and one powerful LED is all you need for a dynamo powered LED headlight!

How it works. The alternating current from the dynamo generator passes through a full-wave rectifier and powers a single high-power headlight LED. The LED current is strictly limited by the dynamo generator to 500..600 mA. You can see for yourself that the LED will shine. Schottky diodes (1N5818) minimize circuit losses. This circuit works for both bottle dynamos and hub dynamos. It produces just over 1.5 W of power.

The above circuit has one problem - the light flickers at low speeds, especially if the power comes from a hub dynamo. This shortcoming can be easily dealt with:

Scheme 2 - reducing flicker at low speed.

The smoothing capacitor reduces flicker at low speed and gives a slight increase in brightness. The larger the capacitance of capacitor C1, the less flicker. C1 requires at least 4V, and the capacity is not limited. Therefore, the only small limiting factors are cost and capacitor size. The circuits work with both hub dynamos and bottle dynamos. Hub dynamos require a larger capacitor to reduce flicker more effectively.

Some tips:

Capacitor C1 can be installed inside the headlight housing, where it must be properly connected to the LED. If the LED is disconnected from the circuit, the capacitor is charged to a fairly high voltage (up to 100 V when driving fast). This is not only life-threatening, but reconnecting the LED causes excessive current, which can even ruin the LED. This is true for most of the diagrams on this page.

Charge your smartphone in the mountains without an outlet: Muscles!

For those who are accustomed to relying on their own strength to charge a smartphone in the mountains, and even on the plains (we are on a hike, without an outlet nearby), distant startupers have carefully built a lot of chargers, indeed, thousands of them.

One of the latest, with the significant name American Red Cross FRX3, contains “inside” not just a neon, but a radio, a flashlight, an external speaker, and a manual generator. According to the manufacturer, one minute of rotating the knob gives 15 minutes of playing music or working with a flashlight.

So, a few years ago the Roto Charger appeared. You get the energy for charging as if you were winding fishing line onto a reel. A minute of active work will turn into three minutes of conversation with a regular dialer.

In this device, and a lot of its other analogs, you will have to turn the handle for a very long time to charge the smartphone. However, to send coordinates to rescuers, such a charge may be quite enough. Therefore, charging your phone away from civilization is also an option.

There are options that are at least less labor-intensive but much more time-consuming. Thus, Filipino teenager Angelo Casimiro created sneakers that generate electricity when walking. The generator consists of two piezo disks in the insole. Two hours of playing basketball is enough for a 10-minute phone charge.

Automatic mode selection.

In circuits 8-10, high power can be achieved as long as acceptable brightness is maintained at low speed by switching from a bridge rectifier to a voltage doubler. Direct, constant participation of the cyclist is required. Some people even like it, since at high speeds they can switch the headlight to a low brightness. Despite this, most cyclists want as much light as possible without bothering with modes while riding. Therefore an automatic switch is required. There are two ways to implement it:

1. Mechanical cable connection in the gear selector. Depending on the selected gear, the headlight operates either in doubling mode in low gear or in bridge rectifier mode in high gear.
2. The switch reads the dynamo frequency and selects the low speed doubling mode, which is implemented in circuit 12.

Scheme 12 - automatic mode selection.

Circuit 12 provides automatic switching between the two modes. It consists of three main parts:

1. Power stage: dynamo, rectifier/doubler, control capacitors, LEDs, channel field-effect unipolar MOSFET switching Q1 & Q2 with their submodulators Q3 & Q4.
2. Scheme for automatically shunting the power supply output when the maximum permissible voltage level is exceeded - T1, D5, R17.
3. Switch IC1 (LM2907) with mode indicator LD11 and hysteresis switch Q5.

The power stage switches between a bridge rectifier and a voltage doubler in the same way as in circuit 8. Due to the specific requirements of the channel JMOS switches, this is not exactly the same circuit, but it works the same way with the same result. The LED circuit increases the voltage stability for switch IC1 and when the maximum voltage level is exceeded, the automatic power supply output bypass circuit is closed, thus protecting the circuit from accidental turning off of the LEDs. Switch IC1 contains a frequency-voltage converter (f2V) and a comparator. An alternating signal from a dynamo is supplied to the input of the f2V block. Frequency switching is set by resistor R15. Output transistor IC1 monitors the base current of channel unipolar MOSFETs Q3 and Q4 as well as indicator LD11. Q5 changes the comparator reference voltage slightly to induce hysteresis. This is necessary to avoid instability near the commutation point.

Circuit 12 provides the same power curves as circuit 8. It can power 3 to 8 high power LEDs in a string and is compatible with bottle dynamos and hub dynamos.

Considering the complexity of the circuit, I made a simple PCB for it. It is optimized for manual assembly; there is no need to use an installation device. Mechanically placed in a 1.125″ head tube with control capacitors C1-C4 located outside the board (placed inside the tube first). Smoothing capacitor C5 is designed for installation in the headlight unit.

For more information, download the CAD files (in CadSoft Eagle format) and complete technical documentation.

There are two more options for circuit 12, which also read the hub dynamo frequency to switch voltage doubler and bridge modes. They are designed to avoid the current surge that occurs in circuit 12 when switching from one mode to another. The circuits exist only on paper, they have not yet been assembled, I am not sure of each component or it is still unclear which ones to use. I can offer two excellent ideas for controlling a channel field-effect unipolar MOSFET when its source potential is constantly alternating with a submodulating potential (switching a variable load).

Alternative #1 for automatic voltage doubler/bridge rectifier mode selection. Not tested. Components are not defined. Designed for professionals.

Alternative option #2 for automatic selection of voltage doubler/bridge rectifier modes. Not tested, components not defined. Designed for professionals.

Let's look at an early design with a different implementation of automatic mode selection (for bottle dynamos only).

We buy on the Internet

A mobile phone has long become an important attribute of a modern person. It is very inconvenient if it suddenly discharges at the most inopportune moment - on the street or even far from civilization. However, you can insure yourself in this case, and the simplest option is a manual charger, with which you can recharge your phone (as well as a tablet or any other gadget) in any situation.

Let's look at several similar devices in this post. We will consider products from Aliexpress, since in Russian online stores the range of such devices is small, and if they are sold, then at a noticeably higher price. It’s easy to order goods from Aliexpress; if you haven’t done this yet, you can find out more about this online store in one of the previous posts.

The functionality of this device for the hunter

A rechargeable dynamo flashlight, due to the fact that it does not require batteries to function, is in demand by hunters, fishermen and tourists. Real dynamo lights are quite expensive, but they serve the purpose - they really last a long time and provide a decent level of quality.

The Eternal Flashlight is indispensable for true trackers. There is no need to save money when choosing a flashlight.

Advantages of a Faraday flashlight:

1. Compact, light. A quality dynamo light is waterproof. Such lamps are very light in weight, they are compact, and have excellent protection against damage and shock.
2. Multifunctionality. Using a flashlight you can charge phones and cameras. Many models are multifunctional because they have built-in compasses and receivers.
3. A large assortment. Choosing a timeless flashlight from a huge variety is very difficult. There are many models, they differ in designs. There are small models, they reach only 5 cm in length. Faraday flashlights come in different power, functionality and designs. Everyone can choose according to their taste, capabilities and needs.

Dynamo flashlight circuit

We propose to assemble an LED flashlight that does not have a battery, but is powered by a capacitor charged by a dynamo. Typically there are 4 wires coming out of the stepper motor corresponding to two coils. Therefore, there are two rectifier blocks in the figure.

List of elements

• Housing 5 x 5 x 2 cm
• LED 3V 20mA 10mm Super Bright White
• Capacitor 1000 uF 16 V
• 2 pcs diode bridges
• Operating mode switch
• Resistors 1 and 10 kOhm
• Stepper motor from printer

One of the options had current stabilization on the transistor - here is the circuit from the stimulator:

DIY dynamo flashlight from a stepper motor

The internal contents of this device do not shine with originality, and consist of a DC motor (about the same as the eject tray in computer CD/DVD drives), a diode bridge assembly, an electrolytic capacitor, a 3.6 V battery with a capacity of 80 mA and an -key" - a cascade on an NPN transistor with an open (hanging in the air) emitter, so that the battery charge is transferred only when the connector is plugged into the flashlight socket (included with the flashlight) and the cellular transistor is “loaded” onto the “dead” battery. The diagram looks like this: