Without a screwdriver, furniture assembly or renovation becomes more difficult. Cord machines are inconvenient to use, therefore, battery-powered screwdrivers are common among professionals and amateurs. The main problem with these devices is the battery recovery process. The kit includes a charger for a screwdriver and a replaceable battery. If the charger is out of order, you need to buy a new product or assemble an analogue at home.
Content
- Battery types
-
Analog chargers
- Pulse charger
- Fixing a non-working battery
Battery types
Household and professional appliances operate on a variety of power sources. Batteries are divided into types, their charging modes are also different. Nickel-cadmium options are characterized by high power, but finding such a product is becoming increasingly difficult due to non-compliance with environmental requirements. Sulfuric acid models are rarely used - the weight is too heavy. Even the low price does not add to the popularity of such batteries.
Lithium-ion batteries are considered the best product on the market. These models have the following advantages:
- complete tightness of the cell;
- significant power density;
- built-in charge controller;
- environmental friendliness and light weight.
The popularity of these types of batteries is due to the simple disposal procedure and safety of use.
Analog chargers
Cordless drills are equipped with a spare battery and charger, which will return the consumed energy to the power source. An analog screwdriver charger is inexpensive. Its construction is primitive, but allows you to provide a constant voltage and the current required for charging. The power supply unit of such a sample is easy to assemble on your own. The universal circuit board will be the foundation for the future product. For efficient heat dissipation, the stabilizer microcircuit will need a copper radiator with an area of 20 cm².
It is important to choose the right transformer so that the 220 VAC voltage is reduced to the required 20 V. The diode bridge is responsible for rectifying the current, but this procedure makes the current ripple. An electrolytic capacitor will help to correct the situation. The "roll" (KR142EN) serves as a stabilizer. The main problem with such a system is the lack of automation. The consumer himself determines the charging time of the battery or can assemble a charge control circuit based on a transistor and a diode.
For domestic needs, affordable Chinese screwdrivers are used. Complete chargers from China do not last long. It is better to assemble a charger for a screwdriver with your own hands and continue to use the technique than to spend money on buying a new product.
Pulse charger
Analog chargers are ineffective when working with professional equipment. A spare battery allows you to continue working, but if the equipment is used intensively, the battery will be discharged faster than the spare will receive the required amount of energy. Long charging process - this is the main disadvantage of analog chargers. Pulse counterparts charge the battery several times faster - and it won't be an hour before the battery is ready for use. It is possible to assemble an analog charger of sufficient power, but the weight of the unit will be too heavy.
The impulse charger has a small size and well-thought-out protection, provides high charge currents. The price of such a product is overpriced. Despite the complex scheme, the assembly will save at least half the market value of the charger. The circuit will have to be assembled on the MAX713 controller, the operating input voltage is 25 V, the current is constant. The user will be able to select the voltage and type of battery. Repairing a charger for a screwdriver of this sample is more expensive than making an analogue yourself.
Fixing a non-working battery
With prolonged work with a screwdriver, most often it is not the components of the device that fail, but the battery (or both batteries at once). Not everyone wants to work with toxic substances that are part of this element. Therefore, the best solution would be to organize an external power supply. As an alternative to proprietary 14.4 V batteries, a car analog may be suitable. To assemble a full-fledged power supply, you will need:
- transformer with 15-17 V at the output;
- diode bridge;
- thermostat.
In extreme cases, you can change the battery power supply of the screwdriver to the mains supply - the alteration is simple.
Buying a cordless screwdriver simplifies the solution of a number of everyday issues. Owners of cheap domestic and Chinese devices, as well as branded professional equipment, can do effective charging with their own hands in case of problems with the complete product. A homemade analogue will not differ in efficiency and reliability if you do everything according to the scheme and using high-quality elements.
