To successfully work with a drill, you need to purchase a charger. The device allows for accelerated charging of the screwdriver battery. Branded models and products from Chinese manufacturers are reliable in operation, and charging the battery of a screwdriver will allow you to work anywhere, even in the absence of an outlet.

Types of screwdrivers and chargers for them

There are many models of screwdrivers on the construction market. They differ from each other not only in price, but in special characteristic features.

Some battery models are of high quality, extending the life of the tool. NiCd, NiMh and Li-Ion are in great demand among consumers - batteries with such advantages as:

• light weight;
• low price.

Many devices differ from each other in the consumed voltage, which is in the range from 10 to 18 watts. Its value is determined by the batteries used. The power of a screwdriver depends on the magnitude of the voltage.

An important characteristic of the duration of the working cycle is the battery capacity of the screwdriver, expressed in ampere-hours (A.h).

Torque is one of the main parameters of the tool. It allows you to screw self-tapping screws into wood. The higher the torque value, the longer the self-tapping screw is screwed into a solid base.

The most common screwdriver has a torque of 11-36 Nm. The torque power regulator allows several operations:

• self-tapping bait;
• screwing screws into thick metal;
• drilling holes.

Set 5 speeds to avoid turning the screws and immersing the head of the self-tapping screw into the base material.

A screwdriver allows you to fix the elements and drill holes. The rotation speed is in the range of 400-500 rpm. During operation, the main speed is used from 1200 to 1300 rpm. With the help of the regulator, the value of the value of its revolutions is changed.

For high-quality work of the tool, chargers are used. They are divided into several types of devices: semi-professional and professional. Depending on the type of work performed, the necessary battery charging is selected. Batteries have a certain operating time, the required power and are designed to work in a screwdriver according to the instructions for use of the device.

Standard battery charging is used to power all chargers having a chemical composition: nickel-cadmium (Ni-Cd), nickel-metal (Ni-Mh).

Charging operates on a voltage of 7.2 to 24 V. You can charge the battery of a screwdriver using a device that operates in automatic mode with voltage regulation and timely shutdown when full charge capacity is established.

The diameter of the screwdriver chuck is from 1.5 to 13 mm. They use a battery with a capacity of 1.5 A, a voltage of 14.4 V. Charging takes place within 1 hour, in addition, a removable battery and a spare element are included in the kit. Some screwdriver battery chargers last 5-6 hours, have a 4V battery rated for 2000 cycles.

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Advantages and disadvantages of screwdriver chargers

Among the various models of screwdrivers and chargers for them, the consumer needs to choose a quality tool. Before you buy it, you need to answer the questions: for what purpose is the tool purchased and how to charge the battery?

Many models have excellent design, small dimensions, light weight, good performance. The original packaging is used - a separate case. Batteries are included and it takes at least 50 minutes to charge the battery. When working, the hands of the master do not get tired, because the handle has 24 steps.

In a large case, you can store additional tools: pliers, screws. The advantages of the model are the presence of a brushless motor and ventilation holes in the hull.

Some models of the charger take too long to cool the battery (within 50 minutes), and the instructions indicate an operating time of 30 minutes. In Chinese models, charging is non-automatic, the service life is no more than 2 years. The impact driver has one battery, which is charged several times during very intensive work.

Heavy screwdrivers have 3 speeds, weight - 2.2 kg, batteries - 18 V Li-Ion. Lithium batteries- the undoubted advantage of charging, which allows you to charge the tool when a discharge of up to 30% of the capacity appears on the indicator.

The disadvantages of the work include the use of non-replaceable batteries. In case of failure, they are replaced only in the service center.

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How to choose the right charger for a screwdriver?

The main secret of the durability of the power supply of the drill is the use of a quality device to charge the battery. The consumer should have necessary minimum knowledge:

• examine the data of the device passport;
• pay special attention to the charging current;
• refuse to purchase goods made in China due to their poor quality and fragility;
• consult with sellers regarding the quality of the goods.

It is unacceptable to use homemade chargers that reduce the battery life of a screwdriver.

If the charger is lost, a universal model is purchased that operates from 12 V for 3 hours.

The Chinese-made battery has 2 drawbacks: there is no rotation speed adjustment at all, and there is also no charging end indicator. The operating time is from 3 to 5 hours.

The type of battery should be determined in advance: nickel-cadmium, nickel-metal-hybrid or lithium-ion. Pay attention to the time during which the battery is charged. The charge of a household drill lasts more than 7 hours, and professional models - about 60 minutes.

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The design of the charger for a household drill

If you want to secure the work process and reduce working time, you should choose a screwdriver with an independent power supply.

The battery supply device consists of a 25-26 W transformer. A voltage of 18 V is supplied to its secondary winding, which passes to the diode bridge through the FU1 fuse.

For operation, 4 diodes with a current of 3 A and an electrolytic capacitor are used, which smoothes the voltage of the diode bridge. Diodes protect the battery from power surges. When the contacts open, the microcircuit is connected to a power source. In the plug-in unit, during its operation, 12 elements are connected in series with each other (each with a capacity of 1.2 V).

The temperature sensor is attached to the nickel-cadmium element. The sensor outputs are connected to the negative pole of the battery and the third connector of the power supply.

In the 3U-A charger, the output cord is connected to the outlet of the screwdriver or to the battery. In some models, when charging, the upper voltage is not controlled, there is a loss of battery capacity. After 15 recharges, the battery fails.

It should be remembered that a working charger provides stable work battery.

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Malfunctions in the operation of the device to provide power to the drill

During the operation of the device that supplies power to the screwdriver unit, many problems occur. One of them is the short period of time during which the battery is used. The main cause of the problem is that an old battery is used for operation or charging fails.

An uncharged power supply leads to a complete stop in the operation of the screwdriver. If a output voltage unit does not correspond to 12 V, 18 V, then the battery must be replaced.

When charging through a faulty socket, the supplying device may become unusable. A defective resistor R7 in the charger must be replaced. In this case, the device that supplies power to the drill is working normally, without load, it forms 8 V at the output.

Often the power supply does not have enough capacity to tighten a dozen standard screws. The main reason for such a malfunction is the failure of the can, its main element.

To troubleshoot, you need to purchase a voltmeter. With its help, it is easy to find failed elements. The use of unsuitable chargers will damage the power supply. The use of non-automatic devices reduces the service life batteries.

How to make a homemade charger for a screwdriver? In the construction business, the main assistant is a screwdriver. Without it, it is very difficult to assemble furniture, when tightening all sorts of bolts and nuts. And if it stops working, then problems immediately arise.

You can, of course, go to the store and buy a ready-made charger, but the price sometimes bites a lot. Sometimes the price is right, but there is no required battery model, and then there is only one way out - to create the charger yourself.

What are the types of batteries? Most often on the market you can find nickel-cadmium batteries. They attract buyers with their size and reasonable price.

This type of battery is very efficient in that it can be charged very often, only up to full charge. But he has one drawback, this kind of toxic, so he was abandoned in Europe.

The next type is nickel-metal hydride, from the point of view of ecology, it is quite safe. These batteries can be left unused for very long periods of time, but should be constantly recharged if necessary. Another popular type is a lithium-ion battery, the disadvantage of which is that this type does not tolerate low air temperatures well, and the price is very high for this species goods.

How to make a screwdriver charger

For a homemade charger, you will need the following materials and tools:

• charging glass;
• damaged battery;
• two wires 15 cm long;
• soldering iron;
• screwdriver;
• drill;
• thermal gun.

Start assembling the battery:

They take a charging cup and carefully open it, glue the terminals and all the electronics with a soldering iron.

Then they take a damaged battery and use a soldering iron to solder the terminals from plus and minus. For further work, do not forget to mark with a marker on the battery cover where there was a plus and a minus.

In the prepared glass, marks are made where the wiring will take place.

With the help of a drill, holes are made, if necessary, then with the help of a blade they are adjusted to size.

The wires are passed through the prepared holes, they take a drill and solder the wires to the glass (it is very important to observe the polarity).

In order to prevent the battery connector from falling apart, a pre-made imitation of a cardboard battery is inserted inside.
The battery cover is attached to the charging glass with a thermal gun.

And the very last step is to attach the bottom cover to the charging glass.

The charger is ready, now you need to insert it into the adapter, and the adapter into the battery.

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Screwdriver device from USB source

You will need the following materials and tools:

• screwdriver;
• socket or socket from the cigarette lighter in the car;
• usb charger;
• fuse from the car 10 A;
• detachable crimp connections;
• dye;
• insulating tape;
• scotch.

Get to work:

To begin with, disassemble the screwdriver into all small parts, you will not need a stator, anchor, gearbox and the entire upper part.
Use a knife to cut off the top case from the handle.

The next step is to work with a drill, you need to drill a hole in the side of the handle and sharpen it a little. There will be a fuse here.

Take wires with crimp ends and connect them to the fuse.

In the case from the handle of the screwdriver, you need to fix the fuse with wires using glue from the gun.

When all this is done, connect to the battery connector.
At the top of the screwdriver, mount the crimp wires to the cigarette lighter socket and use a glue gun to secure everything well.

To fix everything well, wrap the entire body of the handle with tape.
Assemble the entire screwdriver and connect everything well with electrical tape.

For an aesthetic look, you need to sand the puttied part and cover everything with paint.

Hello dear visitors. I want to offer a simple charger circuit for sealed screwdriver batteries. The scheme is shown in Figure 1.

The basis of the circuit is a three-terminal integrated adjustable positive voltage stabilizer KR142EN12A. The stabilizer allows operation with load current up to 1.5A. This parameter limits the maximum battery charge current.

The scheme works as follows. An alternating voltage of 12.6 - 13V, taken from the secondary winding of the mains transformer, is rectified by a diode bridge VD1 - D3SBA40. It can be replaced by RC201, RS201, KBP005, BR305, KBPC1005, or a bridge can be assembled from individual diodes with a direct rectified current of at least two amperes. At the output of the rectifier there is a filter capacitor C1, which reduces the ripple of the rectified voltage. There is already a constant voltage on the capacitor equal to the amplitude value AC voltage 12.6 ... 13V. Those. 12.6 √2 ≈ 17.7V. This voltage will be if ready-made incandescent transformers are used as a mains transformer, for example, TN17, TN18, TN19 with the appropriate connection of the secondary windings. I have a transformer - rewound TVK-110L1. The operating voltage of its secondary winding is 14V.

From the rectifier, the voltage is supplied to the integral stabilizer DA1, the output voltage of which is set using the resistor R4 at the level required for your particular battery. For example, you know that the voltage of a fully charged battery is 14.1V, then this voltage must be set at the output of the stabilizer. Resistor R3 serves as the charging current sensor, in parallel with which a tuning resistor R2 is connected, using this resistor, the charging current limiting level is set, which is equal to 0.1 of the battery capacity. The power dissipated on the resistor R3 is equal to I2 charge R3 = 1.52 1 = 2.25W, so you can use a two-watt resistor with a nominal value of 1 ohm, but the charging current must be slightly reduced. In general, this circuit is a voltage regulator with load current limitation. At the first stage, the battery is charged with a stable current, then, when the charge current becomes less than the limiting current, the battery will be charged with a decreasing current to the stabilization voltage of the DA1 microcircuit.

The charging current sensor for the HL1 indicator is the diode VD2. In this case, the HL1 LED will indicate the passage of current up to,? 50 milliamps. If the same R3 is used as a current sensor, then the LED will go out already at a current of ≈0.6A, i.e. the end of battery charging, judging by the extinguished LED, would have come too soon. The battery would not be fully charged. This device can also charge six-volt batteries. By the way, you can figure out whether it is possible to charge batteries with a voltage of 1.25V. The voltage at the input of the stabilizer DA1 is 20V, the charge current is allowable - 1.5A. the initial voltage on the battery is one volt, which means that in this case 20V - 1V = 19V will drop on the microcircuit. At the same time, a power equal to U I \u003d 19V 1.5A \u003d 28.5W will be released on it. The maximum allowable power dissipation for KR142EN12A is 30W. Those. provided that an appropriate heatsink is used, it is also possible to charge a separate battery cell with a voltage of 1.25V. The radiator area for a given power can be estimated from the diagram.

The charger is assembled on printed circuit board, which can be downloaded here. The specific details I applied are shown in photo1. Well, I think that with the layout of the board in lau format, you can apply other components by changing the pattern of the conductors. If you use TVK-110L1 as a network transformer, then the primary winding can be left completely, i.e. 3000 turns. So, in this case, the number of turns per volt will be equal to W1volt = W1/U1 = 3000/220 ≈ 13.7. The number of turns of the secondary winding will be equal to W2 = U2 W1volt = 12.6 13.7 ≈ 173 turns. Wire diameter D = 0.7√I = 0.7 √1 = 0.7mm - for a charge current of 1A. If the secondary winding is not removed in the core window, then you will have to sacrifice a small no-load current of the transformer and recalculate the number of turns primary winding for another ratio. We consider. The cross-sectional area of ​​the TVK-110L1 core Sc = 6.4 cm2 (SHL20 × 32), W1volt = 50/Sc = 50/6.4 ≈ 8 turns per volt, then the number of turns of the primary winding will be 220 8 = 1760 turns. You will have to wind 3000 - 1760 = 1240 turns. Well, you can count the secondary winding yourself. If you have any questions, then I have a request, ask them on the forum. Perhaps the answers to them will be of interest to other visitors to the site. Goodbye. K.V.Yu.
Download the scheme and drawing of the printed circuit board.

A screwdriver is a tool that almost every home craftsman has. Like other electrical appliances, it requires a connection to the network or accumulates a charge. Most common last option. Removable battery requires charger. Usually it is in the kit. However, like any other device, charging for a screwdriver is not immune from breakage. To restore the tool to working order, you will have to purchase a replacement or make it yourself.

Kinds

There are many chargers suitable for certain brands and models of tools. All of them can be divided into main types.

Analog with built-in power supply

Analog with built-in power supply - quite in demand. it explained by the low cost. Usually not related to professional equipment, quickly fail and "there are not enough stars from the sky." The minimum task, which, as a rule, is set by their manufacturers is to obtain a constant voltage and current load necessary for operation.

Devices work on the principle of a stabilizer. You can do it yourself using the diagram below. To work, you need to remember:

1. The voltage at the output of the charging unit is greater than the battery rating.
2. Suitable for any type of battery.
3. You can use a regular circuit board.
4. Such stabilizers apply the compensation principle: unnecessary energy, heat is removed. To dissipate it, you can take, for example, a copper radiator. Area - 20 cm².
5. The input transformer (Tr1) changes the voltage from 220 to 20 V. Its power is determined by the current and voltage at the output.
6. The current is rectified by a diode bridge (VD1).
7. You can borrow the solution of manufacturers: the assembly of Schottky diodes.
8. After rectification, the current is pulsating, which is harmful. For smoothing, an electrolytic capacitor (C1) is needed.
9. KR142EN is used as a stabilizer. For 12 V, its index is 8B.
10. Management - based on a transistor (VT2) and resistors (tuning).
11. Automatic shutdown after charging is usually not provided. You will have to determine the required time yourself. Alternatively, you can use a circuit that includes a diode (VD2), a transistor (VT1). After charging, the LED (HL1) goes out. There are more serious options with a switch and electronic key that turn off automatically.

If the tool is budget, the circuit of its “native” charger may be simpler. It is not surprising that such products quickly fail. Sometimes a relatively new screwdriver is left without charging. Using the scheme discussed above, you can responsibly approach the issue and the device will most likely last longer than the purchased one. Suitable transformer and stabilizer are determined individually for a particular screwdriver.

Analog s outdoor unit, as the name suggests, are:

Block - regular, includes:

• transformer;
• diode bridge;
• rectifier;
• capacitor filter.

Factory builds usually don't have a heatsink. Its role can be played by a high power resistor. One of the typical causes of breakdowns is in thermal conditions.

To fix the situation, you first need to find out if the power supply is working. If it functions, it is supplemented with a control scheme, if not, another one is sought. It is quite suitable, for example, from a laptop. It has 18V output, which is quite enough. The rest of the details are usually easy to find. They cost very little, you can borrow from other equipment.

The control block diagram is shown below. The transistor KT817 is used, for amplification - KT818. Need a radiator. The approximate area is 30-40 cm². Up to 10 W will be dissipated here

Many Chinese manufacturers are trying to save on literally every little thing. This should be avoided if more or less decent quality is needed. AT homemade scheme there is a 1k ohm trimmer. It is needed to accurately set the current. The output is a 4.7 ohm resistor. It dissipates heat. LED will notify you when charging is complete

The resulting control board is about the size of a matchbox. It fits perfectly in the factory box. There is no need to take out the radiator for the transistor. Enough air movement inside the case

Pulse

Analog devices take a long time to charge: an average of 3-5 hours. Although for domestic purposes it is not scary. Another thing is the professional sphere, where “time is money”. There is such production - accordingly, in a set usually two accumulators.

Professionals often use pulse chargers. They are have an intelligent process control scheme. Time full charge impressive: about one hour. Of course, you can make the same fast analog charger, but then its weight and dimensions will be impressive.

Pulse devices are compact and safe. High quality requires a thoughtful, complex scheme. However, you can repeat it. The circuit below is suitable for NiCd batteries with a third signal pin.

The well-known MAX713 controller is used. Input voltage -25 V. Power supply - simple, so his schema is not here.

The resulting charger for a screwdriver "is distinguished by intelligence and ingenuity." It checks the voltage and turns on the boost charge mode. The battery is ready in about 1-1.5 hours. The scheme allows you to choose:

• charge voltage;
• Battery Type.

It indicates the value of the resistor (R 19) for switching modes and the position of the jumpers. Using the proposed drawing, you can repair the breakdown. An additional incentive will be a financial issue. Saving at least twice.

Charging with a defective battery

Sometimes it happens that the screwdriver itself works, but the battery is broken. There are several options for solving the problem:

Models with different voltage

It is not enough to decide on the type of charger and the brand of the manufacturer; to purchase, you also need to know the voltage of your screwdriver. The most common options are 12, 14 and 18 V.

12 V chargers

The circuit may consist of transistors up to 4.4 pF. This can be seen on the charger diagram for a 12 volt screwdriver. Conductivity in the circuit - 9 microns. Capacitors needed to control clock spikes. The resistors used are usually field resistors. Tetrode chargers have an additional phase resistor. It protects against electromagnetic vibrations.

12V chargers work with resistance up to 30 ohms. Often they can be found on 10 mAh batteries. Among well-known manufacturers, Makita is more often used.

14 V chargers

The diagram shows that five transistors are needed for charging at 14 V. Other features of the circuit:

• the microcircuit is suitable only for four-channel;
• capacitors - impulse;
• tetrodes are needed to work with 12 mAh batteries;
• two diodes;
• conductivity - about 5 microns;
• the average capacitance of the resistor is not more than 6.3 pF.

Devices created according to the scheme can withstand current up to 3.3 A. Triggers are rarely included in the circuit. The exception is Bosch products. For Makita products, flip-flops are successfully replaced with wave resistors.

Chargers for 18 V

The 18 volt screwdriver charger uses only transition-type transistors in the circuit. Other product features include:

• three capacitors;
• tetrode and diode bridge;
• grid trigger;
• current conductivity is about 5.4 microns, sometimes chromatic resistors are used to increase it.

The use of high-conductivity transceivers is a feature of the domestic company Interskol. current load can reach up to 6 A. Makita often uses high quality dipole transistors in their models.

Whichever manufacturer of screwdriver is chosen, the problem of replacing the charger can be easily solved. To do this, it is enough to at least know some of the features of your instrument.

A cordless screwdriver is an alternative to a conventional screwdriver for both small tasks and large home renovation projects. The tool is affordable, easy to use, and a special advantage is the lack of wires common to power tools. For periodic recharging of batteries, a charger for a screwdriver is used.

Benefits of cordless tools

Today, there are many devices that successfully cope with installation work using fasteners: screwdrivers, drills, drilling machines, many of them have a charger for a screwdriver.

Small, light, mobile and self-contained screwdrivers offer the following advantages:

Wireless power supply device

Sometimes it is not possible to purchase a new charger for older models of a tool and you need to modify it or make a new one yourself. Ni-Cd and Li-ion lead acid batteries will require an 18 volt screwdriver charger circuit. The main features of this universal source are:

1. Voltage direct current.
2. Automatic shutdown when fully charged.
3. The maximum current is 5 amps, the batteries can be charged normally.
4. Fully customizable mode according to battery specifications.
5. Low cost.
6. Optimal wiring. No special parts are required, they are all standard and readily available.
7. LED indicators to monitor cutoff and charging status.
8. Suitable for garages and home use.

This multi-purpose fixture is a 5 amp DC source, however, charging less current may require an additional DC circuit between the input power supply.

When deep charging, the battery may overheat, which must be protected by automatic temperature controller circuit or fan cooling. List of parts for repairing a screwdriver with your own hands:

1. Resistors.
2. Capacitors.
3. Simistry.
4. Zener diodes.
5. Reducer.

Repair of power sources

Batteries do not really have complicated spare parts, as they are assembled from the simplest charging cells. In order to determine the repair, you need to open the source and check for damage. Tools and materials that will be needed when performing repairs:

• Multimeter.
• Screwdriver.
• Electrical contact cleaner.
• Insulating tape.

There are times when the coil of a cordless screwdriver is defective and therefore overheats the device. The insulation melts easily, the batteries fail and the cordless screwdriver cannot be used. A technical error cannot always be determined by external inspection and disassembly of the tool is necessary.

Sequence of operations:

Diagnostics of the state of the power tool

Hot surfaces on the cordless screwdriver and battery indicate that the tool is overheating. Overheating is a process that can happen in two ways. On the one hand, the screwdriver has an internal defect, and on the other hand, it is possible that it is not used correctly. To do this, before repair, you need to check:

Screwdrivers are produced by a large number of companies, tools from Interskol, Bosch, Makita are especially popular. Usually they are extremely strong and reliable, however, individual parts can wear out. For example, when the drill does not work when the trigger is pressed. Such a breakdown indicates that the trigger (button) does not work. Replacing a trigger is a fairly simple operation. The battery must be removed before starting repairs to prevent injury when the engine is triggered. The procedure for replacing the regulator using the example of a charger for a Bosch screwdriver:

Another type of repair for a Bosch screwdriver, for example, or from another well-known manufacturer, is required much less often and it is better to entrust it to a service center.

Cordless screwdrivers are pretty reliable these days, so it's actually hard to find failures of the 18V model. Lithium-ion batteries have great time battery life and low speeds self-discharge, thanks to which the tools equipped with them are constantly used in the household.