The Screwdriver Does Not Work What Is The Reason

Cartridge

Keyless chucks are usually used in screwdrivers. The chuck of the screwdriver contains jaws that are tightened with a threaded cone in the direction of the axis and hold the shank of the replacement tool. These jaws move along the threads on the taper and are held in the bushing grooves. As a result of the ingress of dirt, abrasives and poor lubrication, the rubbing surfaces of the jaws and the cone wear out. These details have to be changed.

In order to disassemble and repair the cartridge, you may need pullers to press its parts out of the body. It is not recommended to knock them out with a hammer due to the risk of breakage of some parts.

How to repair a battery with your own hands

A preliminary check is required to repair the battery. To do this, the battery is charged and tested for the output power for a certain time. If the charge is low, nickel-cadmium batteries can be recovered.

In case of undervoltage and too little current, the battery has to be repaired. Repair consists in finding faulty items and replacing them. Lithium-ion battery packs require the use of charge balancing controllers due to the battery series connection, which can significantly complicate repairs and require the assistance of a qualified electronics technician. This is especially important because lithium-ion batteries, if improperly repaired, can become source of fire.

Replacing brushes

Replacing brushes is quite common, especially for screwdrivers used by builders and fitters who work with stone or near a stone dust source. For example, it is enough to assemble a wooden rack in a warehouse with cement with a screwdriver so that the brushes are almost half worn out.

To replace the brushes, you need to disassemble the screwdriver, remove the motor and then remove the brushes. How this is done depends on the design of the engine. Sometimes the brushes are fixed with plugs (this is the easiest case to replace them), and sometimes they are pushed out towards the collector axis. In some cases, you have to resort to devices to temporarily hold the brushes during assembly.

How to extend the life of an instrument?

The screwdriver must be protected from dampness, extreme cold and dust. Batteries should be stored and charged according to their own instructions, if included. Also use only your own charger. Before going to work, you need to charge both batteries in advance.

When working overhead, it is useful to put a tight cap made of nylon or a piece of cardboard on the bat as a protective washer against debris. In this way, the chuck of the screwdriver is well protected. It is never necessary to lay the screwdriver side by side; it is better to place it vertically on a table or shelf near the work place if there is no danger of dropping it from a height. This will prevent debris from getting inside.

Do not operate in drill mode all the time (with the ratchet off). When screwing in self-tapping screws, select the optimal tightening torque, starting with small ones. Also, do not get carried away by the long work of the ratchet, this will quickly wear out the torque limiter clutch.

Engine

The screwdriver motor can be assembled entirely in a metal case.

In this case, it has a magnet instead of the stator field winding.

This slightly increases its reliability, but can be a significant hindrance during repairs.

Such engines are often made non-separable and not repairable. Plain bearings are used in such motors. If it is possible to disassemble a motor of this type, then the armature can be rewound or brushes replaced.

In the case when the motor has a stator winding, the screwdriver body itself serves as its housing and bearing shields. These motors use rolling bearings with “eternal” life-long grease. Sometimes you have to change them. Sometimes the fan impeller breaks from foreign objects entering the ventilation slots.

Often it is necessary to rewind the stator or rotor of the motor together with replacing the insulation in the grooves, replace worn brushes or grind a collector with a worn surface.

Force regulator

The force regulator is most often referred to as an engine speed regulator. Structurally, it is performed together with “trigger”, button on the tool handle. All parts are assembled in a plastic case. Inside there is a power MOSFET transistor, which is controlled by a PWM controller made in the form of a chip with a minimum number of external elements.

The control signal is obtained from a variable resistor associated with the button slider. The variable resistor itself is damaged; the dust that enters it erases the carbon coating and the speed is regulated by jerks or completely fails. Replacing with a similar one helps to solve the problem.

When examining, keep in mind that field-effect transistors are sensitive to static electricity, which destroys them, and take measures against it: grounding strap, clothes made of natural materials.

Self-diagnosis instructions

Before proceeding with self-diagnosis of the refrigeration unit, you should make sure that it is connected to the network, it is standing securely and the doors are tightly closed. If all these conditions are met, then you can proceed to the equipment diagnostics, which includes the following actions:

1. Pay attention to the Defrost button, especially if its place is inside the refrigerator compartment. It often happens that the user accidentally presses the button himself, thereby activating the defrost function.
2. Pay attention to the seals on the refrigerator doors. It is not an exception that in the refrigerating chamber, these elements simply broke or lost their former flexibility. They must be replaced. This is often found in units that have served for more than one year. In this case, it is necessary to leave the door on the freezer compartment loosely closed, because in this compartment, most likely, a layer of ice is frozen, which prevents the door from closing tightly, due to which the temperature in the main compartment rises slightly.
3. Often the unit does not cool down due to a faulty sensor. This can be checked by changing the temperature control.
4. You should bring your hand to the motor located in the lower recess of the equipment. If it is very hot, it is likely that the motor thermal protection has been activated due to overheating of the refrigerator. It is necessary to turn off the equipment and move it slightly away from the wall. If after some time, when the refrigerator has completely cooled down, when turned on everything began to work properly, the problem was only that the engine did not have time to cool down.
5. You need to measure the voltage on the motor with a tester. If it is absent, then the problem was the failure of the refrigerator thermostat.

Thus, with self-diagnosis, you can identify and eliminate common minor malfunctions, why the refrigerator works, but the freezer does not fulfill its tasks. However, if, after these actions, the refrigerator still does not freeze, the reasons may be more serious.

The main reasons why the refrigerator works, but does not freeze

Quite often there are situations when the refrigerator works, but does not freeze. In this case, you should not rush to call the master, because perhaps the cause of the breakdown is not as complicated as it might seem.

Today we will get acquainted with the information on how to independently diagnose the refrigerator, and also consider the most common reasons why the refrigerator does not freeze, but the main compartment continues to work.

Possible refrigerator malfunctions

If the engine has been working properly for some time, while the engine sounds are heard, but then it turns off, and there is no cold, then most likely the motor compressor cannot start. Additionally, clicks can be heard after about 10 seconds. Humming of the motor compressor, this activates the thermal protection located in the thermal relay. over, the motor tries to re-start after 3 minutes.

There may be several reasons for this behavior, namely:

• Failure of the relay;
• The starting capacitor was broken;
• Burned out motor.

What actions should be taken in such cases? The relay is fixed on the motor compressor, so you need to inspect the relay and, if periodic clicks are detected, it can be concluded that it is working properly. And if this part is silent, you will have to replace it.

The capacitor for starting the motor can be checked with a tester. To do this, you must first discharge it through the resistance. If the capacitor is in good working order, the arrow of the tester, set to measure resistance in mΩ, should first fall sharply, and then return to its initial position.

If the condenser turned out to be working, but the refrigerator still does not freeze, then most likely you will have to go to a workshop to replace the burnt out motor.

Quite often, the cause of the failure of the freezer is the leakage of freon from the system. This confirms the long-term operation of the engine and the presence of cold condensation on it. Evaporation of freon may occur due to the formation of microcracks in the evaporator. This happens often after tearing off a frozen product from the wall along with ice, as well as after strong vibration during prolonged operation of the unit. Another reason for the leakage of freon can be broken tubes that go to the evaporator from the compressor, for example, as a result of moving equipment. It is difficult to independently determine the location of the freon leak, as well as to do it after soldering and gas injection.

If the equipment does not cool, clogged refrigerant capillaries may also be the cause. In these situations, it is also necessary to seek help from a specialist, since without certain equipment it will not be possible to push the system.

If you have experience with electrical appliances, you can try to repair the refrigerator yourself.

Runout of the screwdriver chuck

The runout of the screwdriver chuck indicates that there is a problem with the tool gearbox located just behind the motor. This is another reason why the full recoil screwdriver does not work.

Screwdriver Planetary Gearbox Parts

The output shaft of this gearbox is the place where the chuck is attached, so if we talk about the runout of the chuck itself, you need to keep in mind the runout of the gearbox shaft. The reasons for this may be the following:

• A) bending of the gearbox shaft;
• B) wear of the gears of the reducer;
• C) failure of the support bearing of the gearbox shaft;
• D) the maximum development of the pins on which the planetary gear satellites are attached.

All of the above parts are of factory origin and cannot be repaired. In this case, the problem of beating the screwdriver chuck is solved by replacing the gearbox parts with new ones.

Why the screwdriver does not work

Repair or installation of furniture is in full swing, and the screwdriver has stopped working. Let’s consider the main causes of breakdowns and how to repair a screwdriver with our own hands (it will also help us with this). To answer the question why the screwdriver does not work, and how to repair it, you need to have an idea about the device of the screwdriver, its main units, among which the following can be distinguished: a gearbox, a reversing device, an electric motor, a speed regulator and if the tool is a self-contained battery (charging battery ).

over, both expensive and cheaper screwdrivers basically have a similar device, which differs from each other in the presence of certain advanced options. From here, we can single out the main reasons why the screwdriver does not work, which almost all models suffer to one degree or another:

• The first thing you need to pay attention to is the serviceability of the battery or the breakdown of the electrical cable from the network (mains screwdriver).
• Failure of the tool trigger button.
• The engine speed is not regulated or poorly regulated.
• Impossibility of reverse switching.
• Chuck runout.
• The electric motor does not rotate.

The engine speed of the screwdriver is not regulated

The lack of adjustment of the screwdriver engine speed significantly reduces the convenience when working with the tool, and also makes it impossible to perform high-quality work. The regulator is located in close proximity to the start button or is made with it as a whole, however, the speed regulator transistor is attached to the electric motor where it is cooled through the radiator grilles.

The location of the regulator of turns of the electric motor (7)

As practice shows, in the event of a similar problem, it would be more correct to replace the speed controller completely with a new one. Fortunately, they are on sale and are relatively inexpensive. All attempts to repair it led to the same conclusion, unless, of course, you are an expert in the field of electrical engineering.

Failure of the start button of the screwdriver

Start button (red) for screwdriver

It is not difficult to get to the failed start button: you need to unscrew all the screws connecting the two halves of the tool body using a Phillips screwdriver. Next, using an electric soldering iron, disconnect the button wires from the electric motor, disconnect the terminals connecting the button with the battery or the mains power cable and remove the problem from the case. In its place we insert a new button, carry out the connection process in reverse order and check the operation of the new part by connecting it to the battery or power cable.

Stages of disassembling the screwdriver button

Faulty battery or screwdriver cable

Everyone understands that regardless of the steepness of the rock drill, its operation is impossible without an energy source. Therefore, first of all, you need to check the serviceability of the battery if you have a mobile puncher and does not depend on the power source. The main reason for the inoperability of the battery is its discharge or long-term operation. The second reason is eliminated by a complete replacement of the battery, and the first by simple recharging using the rectifier supplied with the sale of the tool.

Disassembled screwdriver battery

As a rule, two batteries are included in the same kit: one is in action, that is, in operation, and the other is being recharged. In the event of a failure of the charger, it will be more rational to replace it with a new one, unless, of course, you are not an expert in radio electronics.

If you are the owner of a power screwdriver, first of all, if the motor does not rotate, check the entire chain of the electric drive: the socket, the cable plug and the cable itself. Believe me, it often happens that the socket fails (contacts burn out), the cable plug may fail for the same reasons, and the cable itself can be damaged as a result of careless handling.

Screwdriver reversing switch

The reversing switch of the screwdriver plays an important role when performing work on screwing in self-tapping screws, as well as removing them if necessary. The reverse circuit of the electric motor is located in the same housing with the speed controller, and the speed redirection switch itself is located in a convenient place on the handle.

Start and reverse buttons located nearby

Switching is carried out by changing the polarity on the terminals by moving the reverse button. Repairing the entire reverse circuit, including the PWM generator located on the board, is reduced to cleaning the switch contacts and replacing the reverse circuit with a new one.

Screwdriver button repair instruction and diagram

The screwdriver is a mobile tool that makes it easier to work with fasteners and screw connections.

Until recently, cordless screwdrivers could only be found in the arsenal of professionals, but with the advent of inexpensive household models on the wide sale, their popularity has increased dramatically.

Unlike an expensive professional tool, budget counterparts have a smaller resource, which is why they often fail.

One of the weakest points of a household screwdriver is the start button and the reverse switch. As practice shows, it is they who break most often.

Over time, the tool stops responding to any manipulation at all. Often there is a problem of the opposite nature, when the motor starts to work spontaneously.

In some cases, to eliminate the defect, it is enough to disassemble the tool and clean it, although more often a complete replacing the screwdriver button. In both the first and second cases, you can fix the problem yourself. Everything in order.

Device and diagram of the screwdriver button

The screwdriver button is the main control element that performs several functions at once:

• Turn on / turn on the instrument;
• Switching the direction of rotation;
• Smooth engine start;
• Speed ​​control.

In this case, each of the controls built into the button block cannot work correctly by itself. Except for the direction of rotation switch, which is more often a separate function block.

In most cases, the body consists of three conventional compartments, in which working units and mechanisms are located.

1. In the lower part of the body there is an on / off control unit and an electric motor speed adjustment.
2. In the middle part there is the trigger of the soft start itself (the deeper you press it, the higher the rotation speed of the cartridge). When pressed, the button slides in a special block along the guides, a variable resistor is responsible for adjusting the speed.
3. In the upper part there is a button for reversing the direction of rotation of the cartridge. The direction is reversed by changing the polarity of the voltage applied to the switch.

This is approximately how all control units of screwdrivers of different brands are arranged. To get acquainted with the device of a button of a specific instrument model in more detail, we recommend that you study screwdriver button diagram (it is in the instructions).

How to repair a screwdriver button if it does not work detailed instructions

To diagnose and repair a screwdriver, you will need the following tools:

• Crosshead screwdriver;
• Narrow flat-blade screwdriver.

As a result of active use of any power tool, dirt will inevitably accumulate inside its body.

Diagnostic steps:

1. We disassemble the tool body. To do this, disconnect the battery, unscrew all the screws (they can be hidden behind decorative overlays that will have to be removed).
2. We check the health of the electric motor. To do this, disconnect two power wires from the control unit and connect them to the battery contacts (the engine should start working).
3. We disassemble the screwdriver button. To do this, squeeze the plastic latches and separate the two parts of the button body.
4. We make a visual inspection of the state of the button for dirt and damage.
5. Next, you need to carefully assemble the screwdriver button, install it in place and test.

INSTRUCTIONS
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If cleaning the control unit did not work, it is necessary to replace the entire button unit.

For this you need:

1. Disassemble the screwdriver (the process is described above);
2. Install the new button in place of the old one;
3. Connect the motor to the button terminals (polarity is not necessary in this case);
4. Assemble the screwdriver by carefully placing the wires in the case.

It is very important to choose a button for a specific model of a screwdriver, since with all the external similarity and visual correspondence, the part may not fit into the grooves. Typically, new buttons are sold complete with battery terminals and transistor.

Repair of mechanical parts

In addition to electrical faults, screwdrivers often have mechanical damage.

Mechanical repair of a screwdriver with your own hands and diagnostics are quite possible in normal living conditions.

Sometimes it is enough to disassemble the device, clean it from dust and dirt, lubricate the rubbing parts and the tool will continue to please the caring owner.

It happens that the tool behaves normally at idle speed, but under load it fails or the chuck shaft simply scrolls.

Unusual sounds often occur when the instrument is turned on or the ratchet is on. This indicates wear on bearings or bushings. The instrument is disassembled and these parts are examined. If the bushing or bearing has clearly visible defects, then they must be replaced.

If an incomprehensible grinding is heard during operation or the tool jams, then the gearbox has broken.

Types of gearbox faults:

• Damaged bearings or bushings.
• Gears have worn teeth.
• Shaft curvature.
• The pin of the satellite is deformed.

If the gearbox shaft is bent or the bearings are worn out, this causes the chuck to run out.

Some tool models can use bearings instead of copper bushings.

During operation, the teeth of the couplings wear out. Slippage begins and, in some rotation modes, no tightening occurs. Then replacement of couplings is required.

Defective gearbox elements are rarely repairable. Most often, new ones are installed instead of them or the gearbox is completely changed.

Repairing a screwdriver gearbox with your own hands is not difficult to do. You need patience, accuracy and then you can repair any faulty device.

Failure of the start button of the screwdriver

Start button (red) for screwdriver

It is not difficult to get to the failed start button: you need to unscrew all the screws connecting the two halves of the tool body using a Phillips screwdriver. Next, using an electric soldering iron, disconnect the button wires from the electric motor, disconnect the terminals connecting the button with the battery or the mains power cable and remove the problem from the case. In its place we insert a new button, carry out the connection process in reverse order and check the operation of the new part by connecting it to the battery or power cable.

Stages of disassembling the screwdriver button

The screwdriver of the reason stopped working. The screwdriver of the reason stopped working. Electrical circuit repair

Problems with electronics are expressed in the inability to turn on the tool, failure of reverse mode switches, problems with adjusting the number of revolutions.

When carrying out diagnostics of the electronic part, one must have certain skills in working with electrical networks and circuits. And then it will be possible to fix the tool of the hitach, bison or any other.

If the tool does not respond to the start button, then start troubleshooting from the battery.

First try to charge the battery in the charger. Then measure the voltage of the batteries with a multimeter. The voltage value must exactly match the declared battery rating. If the indicator is much lower, then it is necessary to determine which element is faulty: a charger or a battery.

The charger is also checked by a tester. A multimeter is connected to the terminals of the charger and the voltage is measured at no-load. The voltage value must be several values ​​higher (up to two volts) than the nominal voltage written on the device case. In the absence of voltage, the charger is definitely faulty.

It makes sense to change battery cells if there is an extra non-working battery available. Then the missing elements can be pulled out of it. The purchase of new cells is unreasonable because their price is comparable to the cost of a new battery.

Deeper knowledge of electronics is required to fix a charger.

If the batteries with the charger are normal, the tool should be carefully disassembled.

When disassembling, you need to remember how the parts were assembled so that you can then assemble them correctly.

It is most correct to draw a diagram of the arrangement of nodes, contacts, screws, springs before starting repair and diagnostics.

Visually inspect the contacts. Are there any darkened among them? If you find dark or dirty contacts, you need to clean them with sandpaper. Special attention should be paid to the quality of soldering.

Two wires run from the start button to the battery terminals. With the battery inserted, the voltage of the button inputs is measured. If there is voltage, the power supply is removed and the inputs to the battery are short-circuited. The resistance at the button input is measured. The option when the resistance indicator is close to zero means that the button is OK.

If the button works, then the problem is in other circuit nodes or in the brushes. If the multimeter shows an open circuit, then the button needs to be repaired or replaced. Most often, the button is damaged because it is the most actively used.

When the reverse is not working, the procedure is similar. The tester probes touch the button input and the motor contact. Then the switch handle is activated. If there is no resistance, then the problem is in the reverse contacts. If the arrow of the device deviates, then the reverse is working.

No rpm control, but the electric motor shows the maximum speed? This means that either the button or the regulating transistor does not work.

If, after checking the entire electrical circuit, no problems are found, but the screwdriver does not work, then there is a possibility that the malfunction is associated with the brushes. Brushes are erased during intensive tool operation. When the length is reduced by forty percent, the brushes need to be replaced. It is possible to solder them, but the solder should only be refractory.

After eliminating the above problems, the operation of the device is checked. If performance is not restored, then it is necessary to check the electric motor.

Faulty battery or screwdriver cable

Everyone understands that regardless of the steepness of the rock drill, its operation is impossible without an energy source. Therefore, first of all, you need to check the serviceability of the battery if you have a mobile puncher and does not depend on the power source. The main reason for the inoperability of the battery is its discharge or long-term operation. The second reason is eliminated by a complete replacement of the battery, and the first by simple recharging using the rectifier supplied with the sale of the tool.

Disassembled screwdriver battery

As a rule, two batteries are included in the same kit: one is in action, that is, in operation, and the other is being recharged. In the event of a failure of the charger, it will be more rational to replace it with a new one, unless, of course, you are not an expert in radio electronics.

If you are the owner of a power screwdriver, first of all, if the motor does not rotate, check the entire chain of the electric drive: the socket, the cable plug and the cable itself. Believe me, it often happens that the socket fails (contacts burn out), the cable plug may fail for the same reasons, and the cable itself can be damaged as a result of careless handling.