An electric drill is one of the most common household tools. And it's very bad when it suddenly stops working. In such cases, I really want to repair the drill with my own hands.
Electric drill device diagram.
The design of a drill or hammer drill is quite simple. Different tool models mainly differ only in the difference in the arrangement of parts and the quality of their manufacture. The versatility of the operating principle and structures used allows you to make independent repair of the drill in most cases of malfunctions.
Any electric drill consists of a body, which houses the electrical and mechanical parts, and a chuck, in which the drill is mounted, on the main shaft of the drill. The electrical part usually contains:
Diagram of the percussion mechanism of the drill.
In turn, a two-phase AC motor consists of a stator and a rotor (armature) with a collector.
The mechanical part includes a gearbox and a bearing system. The gearbox transfers the rotation of the electric motor to the drill shaft, reducing the rotation speed. A more complex mechanical part in a hammer drill (hammer drill). The hammer drill's reducer provides the percussion-translational and rotational movement of the drill (drill). Its design, in addition to the gear, includes pistons (shock and flying), ram and firing pin.
A malfunction of the electrical part manifests itself in the form of a lack of rotation of the engine, i.e. when there is no indication that the engine is running (hum, vibration, etc.). If the impact drill does not turn on, and the cartridge is easily turned by hand, then we can safely talk about a malfunction of the electrical part. The same can be said if there is no speed control or reverse rotation. An expected malfunction in the electrical part is indicated by sparking during the operation of the drill. Temporary interruptions in the operation of the drill, extraneous noise can also indicate an electrical circuit.
Most often, a malfunction in the electrical part is due to wear of the contact brushes. If they are cut by 40%, then sparking and malfunctions can be observed. With more wear on the brushes, the electric motor simply does not turn on. The procedure for determining the culprit of a malfunction in the electrical part is recommended as follows (as available). First, the tester determines the integrity of the cord (cable). Then the operation of the start button (switch) and the integrity of the starting capacitor are checked. Then the contact buttons are removed and checked. Finally, the integrity of the motor windings is determined.
A clear sign of a mechanical problem is a jammed drill shaft. If the cartridge cannot be rotated by hand, and at the same time you can hear the hum of the electric motor when turned on, then the reason lies in the breakdown of the gearbox or bearing. The most common cause of mechanical failure is the failure of thrust bearings. A breakdown of the gearbox can also appear in the case when the chuck is turned by hand and the electric motor is running, and the rotation is not transmitted to the main shaft. A malfunction in the mechanical part can cause periodic malfunctions (temporary stoppages) of the drill, hum, grinding and insufficient shaft rotation speed. In rock drills, a malfunction in the mechanical part can remove the impact movement of the drill.
Finally, a malfunction can manifest itself in the drill chuck. So, it can be difficult to remove the drill when the cams do not open due to breakage in the engagement inside the chuck. Sometimes the malfunction manifests itself in the form of scrolling the chuck relative to the drill shaft. In this case, a malfunction occurs in the area where the chuck is attached to the shaft.
One of the most common causes of malfunction is wear or burning of contact brushes. The first signs of brush wear appear in the form of sparking in the contact area of the brushes with the electric motor armature and minor malfunctions of the drill when the load is increased.
The location of the contact brushes inside the drill.
Many drill models have simplified access to the brushes, and changing them is not difficult, and some drills require disassembling the body and removing the brush holder. The brushes must be replaced with new ones equal in size to the failed brushes.
They should be firmly attached to the brush holder. The electrical contact of the lead wire must be tightened well. The contact of the brush with the armature collector must be reliable. It is necessary to check the action of the spring.
Failure of an electric motor is the second largest cause of a drill malfunction. This is due to damage to the stator winding or armature. Such damage occurs due to a factory defect in the windings or improper operation of the drill (long-term operation without interruptions, the load in excess of the permissible load when the drill is jammed, etc.). As a rule, electrical breakdown of the winding is easily identified visually or by the characteristic burning smell. If there are no visible manifestations, then the motor windings should be checked with a tester, ohmmeter and megohmmeter for the value of resistance. There may be three types of wire damage - short circuit between turns, breakdown of a turn to the body, or wire breakage. Repair of the stator or armature is not carried out independently.
Drill motor connection diagram.
To replace the elements of the electric motor, the drill body is disassembled, the contact brushes and lead wires are disconnected, and the electric motor is removed together with the support bearings.
If necessary, retract the drive gear. The faulty element of the electric motor is disconnected and replaced with a new one or the old one is installed after repair (rewinding) by professionals.
The switch (start button) and the rotational speed regulator in the drill are usually combined. The speed is regulated by pressing the button with different efforts. First, you should check the presence of voltage at the input and output terminals of the button. If there is no signal, then carefully remove the button housing and inspect all contacts. As a rule, burning or sticking of contacts is determined visually. All contacts must be thoroughly wiped with alcohol and cleaned with sanding paper. After that, the presence of voltage should be checked again. If there is no signal, the button should be replaced with a new one. The cause may be a violation of electrical contact with the wire. In this case, the wire must be soldered.
Drill button connection diagram with reverse.
The reverse rotation mechanism is based on a system of make and break contacts. Its prevention is carried out in the same way as the start button. In addition, you should check all the wires of the mechanism going to the brushes and the stator of the electric motor.
The reason for the impossibility of starting the electric motor may be the failure of the starting capacitor. Usually, a non-working condition of a capacitor is noticeable by a color change. But it is more reliable to measure its capacity and compare it with the nominal value.
Checking the electrical part begins with determining the integrity of the power cord (cable) using a tester or ohmmeter.
The resistance between the contacts of the plug is measured (determination of the short circuit of the wires) and the resistance of each core.
A jammed chuck or a grinding noise indicates a failure of the gearbox or bearings.First of all, you should disassemble the drill body and inspect the condition of the gears in the gearbox. The wear of the mounting splines or the destroyed teeth of the gears indicate the failure of the part. This gear must be replaced. The gears are inspected along the entire circumference, smoothly turning the shafts by hand.
The bearings are checked by turning the shaft in them. If the shaft is sluggish, start by lubricating the bearings. If this does not help, then they are removed from the axle using a special puller. The bearing cage is scrolled by hands. If movement is difficult or extraneous sounds are heard, then the bearing should be replaced.
During prolonged use of the drill, the cartridge may fail. Sometimes this manifests itself in the impossibility of removing the drill - the adjusting sleeve does not rotate or, on the contrary, it easily scrolls, and the jaws do not move apart. This indicates wear of the gear joint in the chuck due to metal shavings and dust. In this case, the repair is reduced to replacing the cartridge. The chuck is usually fastened to the shaft with a left-hand thread and is fixed with a screw. The cartridge can be removed by unscrewing the screw and turning the cartridge in the opposite direction with force. In some models of drills, the chuck is installed using a tapered surface in an interference fit. In this case, it must be knocked out with light blows to the end from the side of the drill body.
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The drill often breaks at the most inopportune moment. In order for this not to become a problem, you should know how to repair the drill yourself. You should understand the design of the drill used and determine the cause of the malfunction.
Of course, it is impossible to say so unequivocally that the buttons on all drills are connected in the same way, there are drills with a reverse, there are direct connections, so this answer will be more informative than carry specific information.
Even on drills of the same type, there is a difference in connecting a button depending on the functionality of the drills, here is an example of connecting an old Soviet drill:
Another connection diagram for a reversible drill, more or less generally accepted:
On some reversible drills, the following contacts are in principle involved on the button:
The upper part of the button interrupts the pole on the electric motor.
The number of sockets (wires) for commutation of the drill button can be different, depending on the functionality of the tool, but at least six - two - mains input 220 (phase + zero) - two going to the capacitor and two going to the winding and brushes of the stator of the electric motor.
If you look closely, you can see short diagrams right on the bodies of some buttons. More precisely and more specifically, you can see the diagram for connecting the button in the manual to the instrument (operating manual)
For example, in many buttons of the Interskol tools, the sockets of the supply wire are made round, this already excludes the remaining four, two of which go to the stator and two to the capacitor.
The electric drill button is connected according to the following scheme:
In total, there are six contacts on the button, into which the wires going to the winding of the electric motor are fixed, the terminal blocks or inlets of the starting capacitor and the supply of the 220V power wire are clamped.
Here is a visual picture with signed contacts, what to connect to.
Here are some wiring diagrams for the drill buttons.
If you are looking for something universal that fits all types of drills, then this is not the case.
Drills are different in type, in power (by the way, when buying a new drill button, you must take into account the power of the tool, otherwise the button will not last long).
The drill can be with or without reverse (the button with the reverse has an additional lever with which the drill switches to reverse rotation).
There is a professional tool, there is a household use.
That is, in order to find the diagram of the drill button (connection), you need to build on a specific model of the drill.
Replacing the drill button, or repairing it, is carried out only when the electric drill is turned off.
If you have an old Soviet drill, then it is extremely difficult to find the original (native) scheme.
An electric drill in a home workshop takes a special place. Therefore, tool breakage is a big enough nuisance. Despite the complexity of the design, it is quite possible to make an independent repair.
2.button with switch-on unit - can be equipped with
reverse switch (speed regulator);
3. shaft rotation speed regulator (or reverse switch);
4.Gearbox housing - carries out load-bearing functions for rotating
5. gears and reducer mechanism;
6. bearings of the shaft of the cartridge and the armature of the engine;
8. brush assembly of the electric motor;
9. chuck with drill or cutter holding mechanism.
The drill never breaks as a whole: one of the elements fails. Having understood the design and interconnection of the power tool assemblies, it will be easier to localize the malfunction.
Drill repair is carried out according to the principle "from simple to complex". You should not immediately disassemble the tool to the screw, and assess the condition of all nodes at the same time.
The drill does not turn on. We start with the power cord (at least before that, you should check the voltage in the outlet and extension cord). Having disassembled the case, we find the cable contacts, and "ring" them with a multimeter.
Important! Do not check the power cable with voltage applied! If the current-carrying conductors break, you can get an electric shock, or organize a short circuit.
We connect to the socket of the mains plug and the opposite terminal of the cord. Then we bend the cable several times along its entire length. Lost contact or its complete absence indicates the presence of an open circuit inside the insulation. If the fracture of the current-carrying conductor is close to the edge, the cable is cut and reconnected. It will just be a little shorter. If the gap is in the middle of the length, it is better to replace the wire. The splicing will be unsafe.
The cord is working properly - we check the switch. We connect the multimeter to the terminals, and press the key. A large current flows through the contacts, sparking occurs (especially when dust enters the case). Contacts can corny oxidized. Carefully disassemble the switch body and clean the contact groups with fine sandpaper.
In case of breakage of metal parts, it is better to purchase a new unit.
If there is an additional contact group in the circuit between the switch and the electric motor (for example, a reverse switch or a speed regulator), we diagnose this node as well.
Next, we check the connecting wires from the switch to the motor brushes. If they are in order, we diagnose the brush assembly.
The springs should confidently press the brushes against the anchor lamellas; we check the carbon elements themselves for wear. If necessary, we change: spare parts are included in the delivery set, or purchased in specialized stores. The armature contact strips can be oxidized or clogged. They can be gently cleaned with fine sandpaper.
A more complex breakdown is failure of the armature or stator windings. Using a multimeter, a short circuit is checked between the body of the unit and the contacts of the windings. Then the resistance is measured. The value should be the same on each winding, the variation in readings should be no more than 5%. Defective windings must be rewound.
This can be done on your own, or in a repair shop (in any case, it will be cheaper than buying a new engine).
Such breakdowns manifest themselves quite clearly. Extraneous noise, grinding, shaft jamming, etc.
The motor rotates slowly and the windings get very hot. Or, during normal rotation, a characteristic hum (grinding) is heard. Most likely - the rotor bearings are worn out or clogged. Having disassembled the drill body, we carefully take out the rotor.It is removed together with the bearings. By twisting the outer clip, you will immediately determine the malfunction. If the bearings rotate tightly, they must be flushed with a penetrating liquid (WD-40 or regular kerosene)
Important! Make sure that no liquids get into the armature winding! Otherwise, the insulating varnish may dissolve, and an inter-turn circuit will occur.
Then grease is placed between the clips for high-revving units. Lithol or graphite grease for automotive bearings will do.
If there is a backlash between the bearing races, the units must be replaced.
Dismantling is carried out with a special puller or with an open-end wrench.
If there are no balls, be sure to find them in the case. Dropped objects can get caught between engine or gearbox parts and damage the entire unit.
The bearings of the chuck shaft are diagnosed and repaired in the same way. Only dismantling them without a puller will not work.
If the mounting place of the outer bearing cage (bed) is worn apart (this happens when the bearing is jammed), you will need to make liners of thin sheet metal. Otherwise, beating will occur when the shaft rotates.
The engine rotates in normal mode, noise and grinding noise are heard from the gearbox housing. The shaft turns unevenly. Worn or destroyed gears of the reducer.
We disassemble the case and examine the gears.
It is advisable to wash the assembly of old grease and rotate the shaft 360 °, controlling the engagement of the gears. If a backlash or excessive wear of the teeth is detected, the mechanical part will have to be changed.
Perhaps a large amount of dust has simply accumulated in the gearbox housing. Together with the lubricant, an abrasive paste is formed. In this case, after flushing the assembly, simply add new grease.
Tip: The grease should be changed periodically without waiting for breakage.
Especially if you often drill stone walls.
The cartridge is broken. For cam devices (turnkey) this is a great rarity, the design is reliable and simple. The unit is exposed to dust, so the internal mechanism can easily jam. Most often, the gripper guides are clogged with small abrasive particles.
If the chuck does not twist well, it is enough to blow it out with compressed air and treat it with a penetrating lubricant.
Attention: The jaw chucks do not lubricate the inside!
It is quite difficult to disassemble a part without a special tool. If some component is mechanically broken inside, you still have to change the entire assembly.
But keyless chucks, on the contrary, are easily disassembled and repaired.
They are not as reliable and do not carry the load very well. To disassemble such a cartridge, it is enough to remove a pair of lock washers. You will easily find a broken or worn part that can be easily replaced.
There are two types of fastening: Morse taper, and threaded. In the first case, you need to inflict several blows with a small hammer on the back of the cartridge. After which it can be easily removed.
To unscrew the threaded fastener, the shaft is held with a wrench (there are special flats on the shaft).
There are no faults that cannot be corrected by hand. If a separate unit cannot be restored, only it changes, there is no need to buy a new drill.
To prevent breakdowns, you should adhere to simple rules:
After dusty work, blow out the ventilation holes and the interior of the cartridge. Keep the instrument clean.
Do not overheat the engine - take breaks for prolonged use.
Refill the grease on the rotating parts periodically.
The drill is considered one of the most popular DIY tools and is used in many types of work. Due to heavy use, tool parts can break and damage the device. Do not rush to the service center: it is quite possible to repair the drill with your own hands and save a lot of money.
If you know the device of the drill and the principle of operation of the tool, then self-repair of the product will not complicate you.
Regardless of the model or manufacturer, all of these electrical tools consist of a typical set of basic components.
Any do-it-yourself drill repair must begin with a visual inspection of all parts. The principle here is simple - from simple to complex, that is, first we check the cord, wiring, contacts, various fasteners, then we start testing the blocks and the engine. It does not always come to a complete disassembly of the product, but in practice you need to be prepared for such a development of events. How to disassemble a specific model, the instruction manual will help.
Regardless of the build quality and manufacturer, the following malfunctions occur quite often:
the electric motor fails due to a breakdown of the armature or stator;
extreme wear of brushes;
bearing problems;
the speed control button does not work;
the contacts of the start button are oxidized or burned out;
breakage of the chuck holding the drill due to wear of the jaws.
If you decide to repair an electric drill yourself, then first you need to diagnose and find a malfunction. It is rarely possible to repair a failed part on its own, as a rule, it is simply replaced with a new one.
Before disassembling the drill, make sure it is disconnected from the mains. Any disassembly begins with the removal of the fasteners. Then we unscrew the screws and self-tapping screws, remove the upper part of the product - all the components remain in the lower part. Drill wiring diagram quite simple - there is no need to separately describe all the elements, everything is already intuitive.
Naturally, it is much more difficult for models with electronic adjustments, but it is unlikely that it will be possible to repair a drill with such units on your own, it is better to entrust this to specialists from the service center.
When the power goes out, you just need to change the position of the product - the reason lies in the cable, most likely one of the wires broke ... It is necessary to disconnect the drill from the mains and check with a multimeter cable. You can use the simplest option - a light bulb and a battery in the same circuit.
Attention! Pulling the cord when the drill is plugged in is strictly prohibited, in order to avoid a short circuit - you will have to rewind the motor winding.
After checking, you can bend it as you like to find the place of the cliff , then a part of the cable is cut off, the wires are stripped and new contacts are created for connection. When a break occurs in the middle of the cable, then it must be completely replaced with a new one. True, thrifty users prefer to connect broken wires by soldering, followed by reliable isolation of the repair site, but there is no longer complete trust in such a wire.
This part has a very simple design, but if a problem occurs, it will prevent the drill from starting. Its work is simple: the key slides in a special block and closes the contacts with a pusher finger. From long-term operation inside the block dust accumulates , which prevents the button from moving and blocks it, preventing the contact circuit from closing. The defect is easily eliminated - open and remove dust with a brush.
Important! Never try to lubricate the sliding surfaces of the button - the dust will mix with the grease and deplete, resulting in the entire unit being replaced.
Not all users know that power from the mains is transmitted to the rotor using brushes made of graphite - during normal operation, constant arcing occurs between them and the rotor. There are times when a wad of dust is crammed between the armature and the brush, and since the dust is a dielectric, the drill will not work until we remove the dust and restore contact.
During use, the brushes gradually decrease, because their lower part is erased. Periodically they need to be inspected and changed - it's easy to do, you just need to have a new set in stock.
When you notice strong sparking in the area of \ u200b \ u200bthe brushes, and have recently changed them, this can happen due to rotor problems or its manifold.
For a thorough check, carefully remove the rotor from the stator. Contacts can be charred or have scale - you need to clean them with sandpaper strictly in the direction of rotation. The reason the appearance of dross there can be long-term work at maximum speed. How to check if the rotor is working properly? Ring the adjacent lamellas with a multimeter - their resistance should be identical.
Do not forget check winding - whether there was a short circuit with the magnetic circuit case. In the event of a breakdown, the faulty winding is rewound independently or taken to a service center.
A visual inspection must be done periodically: in case of overheating, when the product worked with maximum loads, the protective varnish could melt and occur turn-to-turn closure ... In this case, the winding will burn out, and the electric motor is unsuitable for further operation. The check is done in the same way as in the case of the rotor - we check the windings with a multimeter. If a breakdown is detected, the stator winding must be rewound.
Leading manufacturers of impact drills pay special attention to the protection of the winding wires, because their products operate in a special mode.
Why is the device still not working if you checked everything and ruled out breakdowns in the electric circuit of the drill? There can be only one answer - the non-working state of the product arose due to the presence of mechanical faults.
Bearings do not work ... Dust gets into the grease due to the breakthrough of the stuffing box, so they wear out quickly and can jam at some point. It is easy to eliminate: we wash the bearing in kerosene, change the oil seals, fill in new grease, better than a special composition for products with high rotation speeds.Broken reducer - a very serious breakdown, you need spare gears, or you will have to replace the entire module. It is only necessary to install the same model. If the drill is a common modification, then it is not a problem to buy spare parts for it in stores.Experts consider one of the most difficult malfunctions breakage of cartridge parts .
During work, drilling waste often gets into the inner part of the chuck, they mix with the lubricant, which wedges the inner jaws. The cartridge must be disassembled, all parts are washed and lubricated before assembly. If extreme wear is found, then the part must be replaced; if the base or sleeve is severely worn, the entire block should be replaced.
We tried to tell you about all the failures encountered during the operation of electric drills. Remember that DIY repairs are always much cheaper than buying a new product.
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Drill repair can be carried out on your own, the main thing is to know the causes of breakdowns and methods of their "treatment". Today we will talk about how the drill button connection diagram looks like, we will not ignore other malfunctions, thanks to which you will be the happy owner of a working tool.
If your tool has begun to work worse, or has completely ceased to perform its direct duties, it's time to diagnose malfunctions and try to cope with them. First, we check the wire for damage and the voltage in the outlet, for which you can turn on any other device - a TV or a kettle.
If you are inspecting battery-powered devices, you need to check them when using the tester - in this case, the voltage indicated on the case should have the same value as the battery voltage.
If the voltage is less, you will have to replace the batteries with new ones. If the battery is working properly, the power supply is normal, look for problems in the hardware. The most common breakdowns are:
Knowing how the electric drill button is connected, you can quickly solve the problem. In addition, a problem with the operation of the drill may also arise due to the dustiness of the tool, because the drill "takes" wood, brick, and other materials. This means that you should take care to clean the device after each use - this is the only way to reduce the risk of malfunction due to dirty tools. That is why after you have carried out repairs in the apartment, immediately clean the drill.
VIDEO Unfortunately, a tester will not be enough for you to check the performance of the tool, which is due to the fact that most of the buttons of the device are equipped with a smooth speed control, and therefore a conventional tester may give you incorrect data. In this case, you need a special wiring diagram for the drill button. Often in tools, one wire is connected to a terminal, and therefore pressing the button at the same time leads to ringing of the terminals. In the event that the light comes on, everything is fine with the button, but if you notice a malfunction, it's time to replace the button.
When replacing, keep in mind that the scheme can be either simple or with a reverse. Due to this, all work on replacing the button must be carried out exclusively according to the scheme, without adding anything "from oneself". So, the part must be suitable in size and correspond to the power of the tool. At the same time, calculating power is a fairly simple task. We use the formula P = U * I (taking into account that the power of the drill is 650 W), I = 2.94 A (650/220), which means that the button should be 2.95 A .
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Despite the fact that this process is quite complicated, you can do all the work with your own hands, observing some important rules. For example, remember that opening the case can cause all parts and loose parts to simply fall out of the case. Naturally, this should be avoided, because then it will be quite difficult to put the device together. To do this, you can gently lift the cover, noting the exact location of the parts on the paper.
The button is repaired as follows:
First, the clamps for the casing are hooked, after which it is carefully pulled together;
All rusted and darkened terminals are cleaned of carbon deposits, for which you can use alcohol or sandpaper;
We reassemble the tool, making sure that all the parts of the device are in place, and we check the performance of the drill - if nothing has changed, we change the part;
We fill the turnover regulator with a compound, and therefore, if the part fails, we simply replace it;
A frequent breakdown is the erasure of the working layer under the rheostat - it is better not to repair it, just waste your time, it is better to buy a new one and replace it.
Many are interested in where to get such a scheme? First of all, it should come with the tool when buying it, but if there is no scheme, or you have lost it, you will have to search the Internet. After all, only with its help you will be able to carry out the repair correctly, without errors. By the way, the speed control button and the reverse control button are located in different places, and therefore they will have to be checked separately.
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There are several reasons for drill armature or stator breakage. First of all, it is the illiterate operation of the device. For example, many users simply overload the tool, carrying out work without interruption. This leads to the fact that the drill motor does not have time to "rest".The second reason lies in the poor winding wire, which is often found in cheap models. That is why breakdowns of cheap tools are much more common. In this case, repairs must be carried out using a specialized tool. And it will be better if you entrust this work to professional specialists.
However, if it was decided to carry out the repair on its own, you will certainly have a question - how to do everything right? As you already understood, an electric drill "suffers" from breakdowns of the armature and stator, and this can be checked by several signs, for example, when the tool suddenly sparks during operation. If there are no "bright" signs, you can use an ohmmeter.
First, carefully disassemble the device case;
We remove the wires and all internal parts;
After finding out the reasons for the breakdown, we change the spare part to a new one, close the case again.
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But the drill may not work due to trivial malfunctions - for example, because of the brushes inside the motor. This means that you cannot do without repairing brushes here, while this work is quite simple - you do not even need to have special knowledge and tools. To do this, we disassemble the device, remove the brush holders from it and change the parts that are broken. By the way, there are models, the body of which can not be disassembled - in them you just need to remove special plugs through the installation window, after which we change the brushes .
You can buy these parts at any hardware store, there are also some models that are sold with a set of additional brushes. It is important that you do not wait until the brushes are completely worn out - check them from time to time. And all due to the fact that there is a risk of a gap between the bristles and the collector. As a result, this part will start to overheat and will disappear over time - which means that you will have to change the whole anchor, which will be much more expensive and more complicated, and it is not a fact that you will be able to solve this issue on your own.
As you can see, there are various breakdowns, many of which will be subject to you, others will be feasible only for specialists in service centers. And in order to reduce the risk of such breakdowns, you need to take care of your tool, clean it after work, check the condition of parts and brushes in order to replace them with new ones in time. However, if you see that you cannot handle it yourself, take the device to the workshop.
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Of course, before taking on the repair of any tool, it is worth understanding its structure. Do not be intimidated by the fact that there are different types of drills. As a rule, they consist of the same parts.
In turn, for the operation of the electrical mechanism, the most important part is the electric motor. This part also includes a brush holder with contact brushes, a button for starting a drill, a mechanism that allows you to adjust the speed of the drill, reverse, a capacitor and a cable.
The mechanical part contains the bearings and the gearbox system. With the help of a gearbox, the element of rotation is transferred from the electric motor to the shaft. It is worth mentioning here that if you are the lucky owner of a hammer drill, the mechanical part there is a little more complicated.To ensure not only rotation, but also an impact movement, it provides for the presence of gears, a ram and a striker.
We figured out the design, now you can go to the types of drill breakdowns.
The first and most obvious breakdown is when the electric motor does not work when turned on. How to check if the engine really junk? You can easily turn the chuck and the drill is not working - the first sign. You cannot adjust the speed - second. The drill sparks, there is extraneous noise or temporary interruptions in its operation - this is the third sign that something is wrong with the engine.
Most often "something is wrong" is the wear of the contact brushes. When they are grinded by more than forty percent, then there is an interruption and sparks fly. If the wear is even greater, then the engine will simply stop working.
But before replacing them, of course, you should check which component is the cause of the breakdown. To do this, use a tester that checks the power cable. It is also important to check the health of the start button and the capacitor. In addition, it is important to inspect the motor windings for integrity.
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Most often, it is not difficult to get close to the brushes in a drill, although there are some models in which you will have to disassemble the case completely.
After you have taken out the old brushes, you need to replace them with new ones. To do this, they should be fixed so that they are well kept in the brush holder, and also the wire supplying power should be fixed tightly. Before assembling the body, you need to make sure that the brushes and the armature collector are in contact, and that the spring is working properly.
Another popular type of breakdown is a malfunction of the electric motor itself. Most often it occurs due to the fact that the stator or the armature in the part of the winding is damaged. The cause of breakdown can be both a factory defect and improper use of the drill, which includes too long time of continuous operation, overload on the drill.
Winding breakdowns are most often seen with the naked eye. If you cannot visually determine the location of the breakdown, you can use a tester or megohmmeter for these purposes. In this case, the winding can be damaged in three ways, it can short-circuit, a breakdown can occur, or the wire can simply break. If the damage touches the armature or stator, then you should not repair them on your own.
If you need to replace some element of the motor, then for this you need to carefully disassemble the case, it is important to properly disconnect the brush contacts and the power wire. After that, the engine itself is taken out and the broken part is replaced.
Another popular type of breakdown is the malfunctioning of the button-switch, which is usually responsible for regulating the rotation speed. At the first stage, a check is carried out, there is tension. In its absence, the button is removed and inspected for an object, whether the contacts are stuck or burnt.
The contacts are wiped and cleaned and reconnected. If the contact with the supply wire is broken, then the wire is soldered. If after these manipulations the button does not work, you will have to change it to a new one.
VIDEO In the same way, the reverse rotation is checked if a malfunction occurs there. Additionally, the wires connecting it to the brushes and the stator are checked.
Another of the most common causes of failure is a malfunction in the gearbox or bearings. It manifests itself most often in such a way that your drill gets jammed or a grinding noise is heard during operation, although you can hear that the engine is running. In this case, the bearings are replaced (most often the support bearing fails).To decide on replacement, a visual inspection for the integrity of the gears along the entire diameter is sufficient.
Checking the bearings is carried out while turning the shaft. If the shaft is difficult to move, normal lubrication may be sufficient to correct the problem. If the bearing still rotates with difficulty, it is replaced.
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