For successful work with a drill, you must purchase a charger. The device allows you to accelerate the battery charging screwdriver. Brand models and products of Chinese manufacturers are reliable in operation, and charging the battery of the screwdriver will allow you to perform work in any place, even in the absence of an outlet.
Diagram of the device charger for the battery screwdriver.
Types of screwdrivers and chargers for them
On the construction market are many models of screwdrivers. They differ from each other not only by price, but by special characteristic features.
Some battery models have high quality, prolonging the life of the tool. NiCd, NiMh and Li-Ion - batteries with such advantages as:
- small weight;
- low price.
Many devices differ from each other consumed voltage, ranging from 10 to 18 watts. Its value is determined by the batteries used. Power screwdriver depends on the magnitude of the voltage.
Comparative table of characteristics of screwdrivers from different manufacturers.
An important characteristic of the duration of the operating cycle is the screwdriver battery capacity, expressed in ampere hours (A.h.).
Torque is one of the main parameters of the tool. It allows you to screw the screws into the wood. The higher the torque value, the longer the screw is screwed into the solid base.
Most common screwdriver having a torque of 11-36 Nm. Torque power control allows you to perform several operations:
- bait screw;
- screwing screws into thick metal;
- drilling holes.
Set 5 speeds of work, to avoid turning the screws and plunging the screw head into the base material.
Screwdriver allows you to fix the elements and carry out the drilling of holes. The rotation speed is in the range of 400-500 rpm. During the work the main speed from 1200 to 1300 rpm is used. With the help of the regulator changes the value of its speed.
For high-quality operation of the tool using chargers. They are divided into several types of devices: semi-professional and professional. Depending on the type of work performed, choose the necessary battery charging. Batteries have a certain time of operation, the required power and are designed to work in a screwdriver according to the instruction manual of the device.
Charger scheme for charging the battery of the screwdriver.
Standard battery charging is used for powering all chargers with chemical composition: nickel-cadmium (Ni-Cd), nickel-metal (Ni-Mh).
Charging works from a voltage of 7.2 to 24 V. You can charge the screwdriver battery using a device operating in automatic mode with voltage regulation and timely shutdown when establishing the full charge capacity.
The diameter of the screwdriver cartridge is from 1.5 to 13 mm. Use a battery with a capacity of 1.5 A, a voltage of 14.4 V. Charging occurs within 1 hour, additionally a removable battery and a spare element are included in the package. Some battery charger for the screwdriver work 5-6 hours, have a battery with a power of 4 V, designed for 2000 cycles of work.Back to table of contents
Advantages and disadvantages of the screwdriver chargers
Among the various models of screwdrivers and charging them to the consumer, you need to choose a quality tool. Before you buy it, you need to answer the questions: for what purpose is the instrument purchased and how to charge the battery?
Many models have excellent design, small size, light weight, good performance. Used original packaging - a separate case. Batteries are included, and you need to charge the battery for at least 50 minutes. When working the hands of the master do not get tired, because the handle has 24 steps.
In the large case you can store additional tools: pliers, self-tapping screws. Advantages of the model are in the presence of a brushless motor and ventilation holes in the housing.
Hitachi charger circuit.
For some models of the charger, the battery cools too long (for 50 minutes), and the instructions indicate the operation time - 30 minutes. In Chinese models, charging is non-automatic, the lifetime is no more than 2 years. The impact screwdriver has one battery that charges several times with very intensive work.
Heavy screwdrivers have 3 speeds, weight - 2.2 kg, batteries - 18 V Li-Ion. Lithium batteries are an undoubted advantage of charging, which allows you to charge the instrument when a discharge of up to 30% capacity appears on the indicator.
The disadvantages of the work include the use of non-replaceable batteries. At failure, they are replaced only in the service center.Back to table of contents
How to choose the right charger for the screwdriver?
The main secret of the durability of the power supply of the drill is to use a quality device to charge the battery. The consumer should have the necessary minimum of knowledge:
- examine the data of the device passport;
- pay special attention to the charging current;
- refuse to purchase goods of Chinese origin due to its poor quality and fragility;
- consult with sellers regarding the quality of the goods.
It is unacceptable to use self-made charging, reducing the time of operation of the screwdriver battery.
Bosch charger circuit.
In case of loss of the charging device, a universal model is purchased, which operates from 12 V for 3 hours.
The battery made in China has 2 drawbacks: there is no adjustment of the rotational speed, and there is no indicator of the end of charging. Opening hours range 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 last about 60 minutes.Back to table of contents
The design of the charger for a household drill
If you want to ensure the labor process and reduce working time, you should choose a screwdriver with an independent power supply.
The battery supplying device consists of a 25-26 W transformer. The secondary winding receives a voltage of 18 V, passing to the diode bridge through the FU1 fuse.
For operation, 4 diodes with a current of 3 A and an electrolytic capacitor, which smoothes the voltage of the diode bridge, are used. Diodes protect the battery from power surges in the network. When the contact is open, the microcircuit is connected to the power supply. In a replaceable unit, during its operation, 12 elements (each with a capacity of 1.2 V) are connected in series with each other.
Screwdriver battery circuit.
A temperature sensor is attached to the nickel-cadmium cell. The sensor leads are connected to the negative pole of the battery and the third power supply connector.
In the charger 3U-A, 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.
Back to table of contents
It should be remembered that a good battery charger ensures stable battery operation.
Faults in the operation of the device to provide power to the drill
When operating the device that supplies power to the screwdriver unit, many problems occur. One of them is a short period of time during which the battery is operated. The main reason for the failure is that an old battery is used to work or charging fails.
Uncharged power supply leads to a complete stop in the screwdriver. If the output voltage of the unit does not correspond to 12 V, 18 V, then the battery must be replaced.
When charging through a faulty outlet, the power supply may become unusable. The defective resistor R7 in the charger must be replaced. In this case, the device supplying the drill with power is working normally, without load, it forms 8 V.
Often, the power supply has insufficient capacity to tighten a dozen standard screws. The main reason for such a malfunction is the failure of the can, its main element.
For troubleshooting, you must purchase a voltmeter. With it, it is easy to find the failed elements. Using inappropriate chargers disables the power supply. The use of non-automatic devices reduces battery life.Back to table of contents
Repair supplying device for drill-screwdriver
Power cordless drill.
Screwdriver - an expensive thing, but it is necessary in the economy. The cost of the battery is most of the price of the drill. Practical owner will not spend extra money on the purchase of a new power supply, and make repairs charging their own hands.
To get the work tools:
- soldering iron;
By the appearance of charging, you can determine the fault. If the diodes are broken in the charge of 18 V and the transformer burned out, then get the diodes FR307 or 607 and the thermal fuse with the primary winding.
Replacing batteries is not difficult. Disassemble the case, replace the elements, even if the case is glued together or assembled on screws.
It is necessary to remember the location of the elements and the order of their connection between them. The battery has 12 elements. Nickel-cadmium blocks have an increased self-charge. Elements in them contain high resistance.
In charging there may be a mains voltage, lowered by a transformer. In the event of a malfunction, current and voltage stabilization is absent, and the LEDs are lit while charging continuously.
Using a soldering iron, they clean the contacts of the batteries. Soldering is performed for 2 seconds to avoid overheating of the unit. During the work it is necessary to observe safety measures: it is necessary to solder with glasses, to spend acid dropwise.
Screwdriver can be remade to work with lithium blocks. In this case, the screwdriver battery can be charged faster and better. The nickel block is charged in the ordinary charger. By the end of charging, the amount of current decreases, the voltage is not controlled by the device, and the battery does not turn off by itself.
The second stage of work is the connection of four blocks with each other. They are placed in the battery compartment and fastened with tape, then connected to the contacts, previously connected to each other with aluminum wires with a cross section of 2.5 mm².
The unit is charged with an adapter: there is a plug on one side and two connectors on the other side (balancing and charging). The power supply of the unit goes through 2 cables connected in series with each other.
If the charger fails, inspect the step-down transformer and charge. Yellowness can form around the diodes, indicating that charging passes current in two directions. As a result, overheating of the transformer windings and breakdown in all the diodes occur. During repair, it is necessary to drain the diodes and solder them.
The transformer windings should be checked (to detect a break in them). When the sensor overheats, it is replaced and restore conductivity. Turning on the device in the network, check the operation of the display device. In case of its serviceability, the device is ready for operation.
Charging the battery with a special device is simple. Properly performed charging will allow you to set an offline mode for the screwdriver, take into account all the nuances in its work and choose the optimal type of battery with a minimum of drawbacks.