How to check the grinder for performance. Dismantling Ushm

Table of Contents:

How to check the anchor of the grinder with a tester

When diagnosing and repairing the electric part of the grinder, it is most convenient to use a multifunctional tester (abbreviated name. Multimeter). If such a device is not at hand, then for some checks a screwdriver with an indicator or a bulb with two wires is suitable. During the repair process, the multimeter allows you to measure both voltage and current values, and engine winding resistance. Indicator and light bulb can only be shown the presence or absence of voltage.

Diagnosis of power breakthrough

Perhaps the most common malfunction of the electrical equipment of the grinder is a break in the power of power inside the lining of the power cable. To diagnose and repair such damage, it is enough to disassemble the rear handle of the grinder and check the voltage on the terminals before the circuit breaker. Another way is to disconnect the cable terminals and use the multimeter to check for the breaks of the resistance of each of its veins.

Stator check and rewind

To check the stator of the electric motor of the grinder, it is necessary to disconnect both of its windings from the power circuit, and then measure their resistance with a multimeter in the range of 200 Ohms. On a good winding, the device will show the resistance of about one ohom, and on a faulty (with a cliff). Dozens or hundreds of misses. If the winding is out of order as a result of a short circuit, then the cargo, as a rule, can be seen from the inside of the stator body. It is impossible to check the stator for an interval circuit with an ordinary tester. For this there are special induction devices. The only ways to repair the stator is its replacement or rewind. The second is possible only in the presence of appropriate qualifications, so most often the stator is simply changed.

Diagnosis of the anchor by the tester

Check the anchor of the grinders both on the cliff of windings and their closure on the core. In the first case, the resistance is measured in a circle between the two adjacent plates of the collector located on the Rotor shaft. All values ​​should be the same (within the same ox), and a significant difference indicates a cliff. In the second measurement is made between the radar radio pipeline and the collector plates. To search for inter.Flip circuit, as in the case of a stator, you must use a special device. If a malfunction is detected, it is necessary to decide on how to carry out repairs: rewinding the anchor or its replacement with a new. It is unrealistic to rewind the anchor windings independently without appropriate skills and equipment, and rewinding in the service will cost almost as much as a new anchor. Therefore, the best option for repair is a purchase and independent replacement of the anchor.

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Checking the start and control unit

Diagnosis of electronic components of the grinder is reduced to determining the serviceability of individual blocks, and repair (if there are no skills in radio engineering). To their complete replacement. The smooth starting device can be checked with an ammeter by comparing the current jump with it and without it. For accurate diagnosis of the unit maintenance unit under load, an oscilloscope is required. Although in order to understand whether it is in principle or not, it is enough just to observe the behavior of the grinder at different modes.

Checking coal brushes

In the process, carbon brushes are erased and when the minimum size is reached, they are subject to replacement. The first sign of problems with brushes is uneven sparking ring around the collector with flashes. Some models have round holes with screw lids to replace and check the brushes on the housing. But in most Bulgarians, in order to change them, you have to completely, as during repair, disassemble the body or rear handle.

Diagnosis of the start button and speed regulator

The most common malfunction in the electrics of the grinder is the failure of the start button, which is most often the result of the dust entering it. You can check the operability of the button using a multimeter or indicator screwdriver, freezing the voltage on its output contact. It is usually not subject to repair and is simply replaced by a new. It is even easier to determine the malfunction of the rotation speed regulator: when the wheel rotates, it or changes the number of spindle revolutions or not. If there are no skills in the repair of such devices, then it is easier to buy a new one for a few hundred rubles.

Why the instrument malfunction most often concerns the rotor?

During work, the grossing of the largest loads occur on the rotor, namely:

With incorrect or too long operation, the breakdown of the electrical appliance can be anchor, it is also called the rotor, which may need to be repaired or complete replacement. But before it is convinced of a malfunction of this particular detail, it is necessary to make sure that it really failed.

How to check a grinder with a multimeter?

In the economy of any home master, not to mention professionals, there is almost always a corner grinding machine (Ushm), which is popularly called “grinder”. The tool is popular, love and respect, so any of its malfunctions is perceived very painfully.But, before going to a specialized department for a new grinder, you should try to independently deal with a breakdown. Having dismantled the Ushm, you can visually detect some mechanical damage, but defects in the electric part must be checked using special tools, one of which is a multimeter. Next, we will consider how to check the grinder with a multimeter.

For what reasons, Ushm can fail

Most often, the tool stops working when the anchor (rotor) is damaged. When opening the body, you can see the burning and uneven wear of the brushes. The indirect signs of such a breakdown are the heating of the tool and vibration during operation.

It is more difficult to detect electrical breakdowns. These include:

Also, quite common reasons for the refusal of the tool can be:

  • The wires of the wires in the power cable and the circuit breaker malfunction. The grinder does not turn on;
  • Interpretation closing in the rotor windings and electronics malfunction leads to the fact that the tool works only at low speeds;
  • Sparking due to erasing coal brushes or strong wear of the engine collector;
  • The appearance of smoke occurs when closing in the Windows of the stator or rotor, as well as with excessively intensive work (when air cooling channels are clogged with dust).

As you can see, many breakdowns are due to the malfunctions of the electrical part of the tool. Therefore, you need to be able to detect them before deciding to send the tool to the repair workshop.

How to call the anchor multimeter

For a competent check, you need to know the principle of operation and the device of the rotor. Its main constructive parts are:

  • A circular core, which is a set of plates made of electrical steel;
  • Winding in a certain way in the grooves of the core.

Following a special scheme, two windings are laid in each of the grooves. Each of the conductors is half the turn. Its ends are connected in pairs on the lamella. The end of the last turn and the beginning of the first are located in one groove and closed to one lamel.

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Before checking the anchor with a multimeter, you need to carefully examine it for various damage:

  • Melted wiring;
  • Burnt insulating varnish;
  • Deformation of the turns;
  • The presence of conductive particles (like residues of solder), which often cause a short circuit;
  • Curvature of the bent edges of the lamellas (cocks) connecting them to the winding leading to the burnout of the lamella;
  • The accumulation of graphite from the collapsing brushes between the lamellas, which also causes a short circuit.

Step.By.Step instructions

Directly checking the anchor by the multimeter is as follows:

  • The probe connectors of the device are inserted into the corresponding nests.
  • Set the resistance measurement mode. Measurement range. 200 Ohms.
  • The probes alternately touch every two neighboring lamellas, fixing the results displaying on the multimeter display. You will have to nickname every couple of neighboring plates sequentially.

We decipher the results

Deciphering the results of checking the anchor multimeter:

  • In the case when the resistance between all pairs of neighboring plates is the same, draw a conclusion about the serviceability of the anchor winding.
  • If the resistance is less than 1 ohm or close to zero, then there is a short circuit between the turns.
  • If the resistance value exceeds the average by two or more times, you need to look for a break in the windings of the winding. Когда сопротивление очень велико, на экране цифрового прибора вообще ничего не отразится, а на аналоговом устройстве стрелка будет зашкаливать.

Checking the serviceability of the stator

The stator is a motionless part of the electric motor, creating an electromagnetic field in which the rotor rotates. The reason for the refusal is often either a short circuit or a break in the windings (coil) of the stator.

Signs indicating the stator breakdown:

  • The appearance of smoke;
  • The smell of burning insulation;
  • Overheating of the body of the grinder;
  • Cessation of rotation of the shaft or its slowdown;
  • Sharp spontaneous set of revolutions.

Step.By.Step instructions

You can also check the stator using a multimeter:

  • The probes connectors are inserted into the appropriate nests on the tester housing.
  • The device is installed in the resistance measurement mode. The measurement range is placed from 20 Ohms to 200 Ohms.
  • The probes are alternately brought to the windings and fix the readings on the screen.

We decipher the results

The results of the call can be as follows:

  • The tester everywhere fixes the same resistance. The coil of the stator (winding) is in good.
  • At some points, the resistance differs. There is a short circuit in the winding, or there is a break in one of the turns.
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Thus, having at your disposal even the easiest multimeter, you can determine the nature of the malfunction of the grinder and make a balanced decision about whether it is worth repairing or better to purchase a new one. Although, for diagnosis, it is better to take the tool to the workshop, where there are more opportunities and devices for expert opinion.

Now you know how to check the grinder with a multimeter.

Replacing the anchor independently at home

Practice shows that if it is decided to replace the anchor of the grinder, then it is best to change it along with the supporting bearings and the impeller of engine cooling.

  • New anchor Ushm. Must match your model. Intranscents with other models. Unacceptable.
  • Takes, wrenches.
  • Soft brush and rag to wipe the mechanism.

How to remove the anchor

Replacing the anchor begins with a disassembly of a grinder. The following steps are performed:

    The brushes are removed by a screwdriver on both sides. Brushes are extracted.

How to anchor in place

To install the new anchor of the grinder in place, you should take a new part, and then assemble the tool in the reverse order. The follower is as follows:

  • A fixation disk is installed on the anchor shaft.
  • The bearing is installed by the method.
  • A small gear is planted and fixed with a locking ring.
  • The anchor is started into the gearbox body, the docking holes are combined.
  • Reducer mounting bolts are twisted.
  • The anchor with the gearbox is inserted into the grinder body and fixed.
  • Brushes besieged to their places, closed with lids.

After performing these actions, the Bulgarian is ready for work. Replacing the anchor is made.

Ancient Sufi wisdom says: “The person who is able to get out with dignity from a difficult situation is Smart. But wise is one who does not fall into such a situation.»Following the rules of operation of household appliances, avoiding overheating of the motor, you can avoid breakdowns and troubles in the operation of the grinder. The content and storage of the tool in cleanliness and dryness will prevent its mechanisms from pollution and oxidation. Timely maintenance of the tool is guaranteed to relieve unpleasant surprises during operation.

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How to rewind a corner grinding machine at home, detailed instructions, video

The next video describes the repair of the grinding machine of the Makita model with increased sparking in the brush-collection node. Determining the causes of the defect was complete diagnosis of the electrical part of the coffee grinder.

The cause of an increased spark was a rupture of one of the windings of the Bulgarian anchor. The author eliminates the defect by winding a faulty winding. After determining the necessary parameters for laying old coils and their subsequent removal, it is done to wind a new winding. She produced using a special tool.

After winding the coil is fixed in grooves with wooden wedges or other soft material. The wires of the windings and the conclusions of collector lamellas (“roosters”) of the author are connected by welding. Be sure to perform this operation to check the coil circuit multimeter and a short circuit indicator.

If there are no ruptures, ruptures or short circuits between the revolutions, epoxy impregnation. Create conditions for high.Quality impregnation by the rotor will preliminarily heat. The author describes in detail the technological methods that contribute to the better stream of resin in the coils.

Since the rotor rotates at high speed, it is important to reduce the load on the bearing nodes. Ensure its good balance

The author of the video only indicates the availability of this technological operation, no more information is provided. After balancing, the collector is pumped into the working position, t.E. Based on bearing nodes. During this processing, mechanical particles can fall on the winding, so the devices should be checked for the presence of ruptures and short circuits.

The same author repairs grinding machines of different models: the first video model is repaired, and in the second video Bosch model model. So the repair technique is the same in both cases.

Important right to determine the parameters and winding scheme unsuccessful rotors on both models. Here, in addition to a visual inspection, the author refers to the location of a closed electric circuit for the wire from the core of the groove with the corresponding output of the “rooster” of the Tester plate, showing the minimum resistance in the presence of such a connection

The author recommends making a graphic representation of the stylization scheme indicating the necessary parameters.

Unlike the previous video, this author specially demonstrates his actions when working on a lathe when removing an old winding, freeing grooves from other bundles of wires and actions when winding the wire. The author is professionally engaged in the repair of power tools, so there is a special device for winding in the arsenal.

After winding the ends, the ends are fixed according to the scheme by bending the excretions of the “bouncers” of the planks. Additionally, the use of natural heat.Resistant threads is made to tie the front wires (synthetics should not be used). Then this is a welding wire with bent ends of the planks and checks for cliffs and short circuits using the corresponding devices.

Checking the stator multimeter

The electric starter is located on the outer section of the electric motor, on top of the rotor. Before checking the stator, it is necessary to dismantle it and get the brushes, and then dismantle the gearbox. Previously, carefully examine the winding and make sure that there are no visible tears and other defects on its surface.

Possible causes and signs of a non.Working stator of the grinder:

  • Sharp increase in voltage;
  • Penetration of moisture inside the engine;
  • Overload of the power tool and the created internal overheating of the nodes;
  • Sharp remove the cord from the outlet, with a working tool;
  • The appearance of the smell of burning rubber or plastic;
  • Overheating of the body;
  • The appearance of smoke from the electric motor during its operation;
  • Slow rotation of the shaft or its complete absence;
  • The grinder dramatically gains speed.

The multimeter allows you to check the presence of a break in stator windings, for this it is necessary to perform the following actions:

  • The meter exhibits the maximum of 200 ohms.
  • They begin to check the errors of the multimeter, for this they touch the probes among themselves, the tester arrows should indicate “0”.
  • Concern the probes of conclusions on the windings, if the scale of the device is shown “infinity”, the winding is not working and rewinds are necessary.
  • Check the presence of a short circuit on the case. A very dangerous state of power tool, which not only causes a drop in its power, but is also a potential source of user electric shock.
  • Include resistance measurement.
  • The red probe is installed at the output output, the black one is fixed on the stator case.
  • With a short circuit winding on the case, on the display r is less than on the working. This failure is eliminated only by rewinding of windings.
  • To measure the inter.Seal short circuit in the electrostator, measure R on a separate winding.
  • Determine the “0” point of the windings, measuring R of each. The smallest resistance will indicate a faulty.

The multimeter allows you to quite accurately determine failures in the work of the anchor and the stator of the engine of the grinder. The discovered failure can be eliminated by rewinding the electric motor or replacing from the remote control. Currently, there are enough such sets in the retail network for most popular Ushm models.

After repairing the stator or rotor, the tool is revealed according to the stored disassembly pictures. Check the performance of the tool. If everything is done correctly, the Bulgarian will serve its owner for more than one year.

Examples of testing anchor

Both anchors of professional tools and medium.Sized equipment can fail. Below your attention we present a specific example of checking the anchor of the Makita GA 9050 angle grinding machine. The power tool is equipped with a powerful 2000-Water collector electric motor. To verify the performance of the anchor of the Bulgarian Makita GA 9050, the contact group of part should be diagnosed directly. Before this, you need to turn on the multimeter and set the measurement mode 200 Ohms. If you have an analog digital measuring device, it is better to use it than digital. After setting a multimeter, you can proceed directly to checking the anchor.

The resistance is measured between each plate. Multimeter probes are placed on each lamella so that the recess between them is located exactly in the middle. If the part is in good condition, the resistance between each of the lamellas should be the same. The divergence of indicators most likely indicates the breakdown of contact. Of course, at home, such a malfunction will not be able to detect. If you notice the gap of the winding outside when checking the anchor, you can try to stock up on your own. Sometimes this allows you to save the situation, and the Bulgarian will serve you for some time. The absence of indicators during the examination of the plates during the check of the anchor for performance indicates their disclosure.

Sometimes a malfunction can be seen visually. In working condition, all the plates of the contact group of the anchor should be even and smooth. In the described cases, the part cannot be repaired and requires replacement. Directly with the anchor should be changed and engine brushes. A new detail can cost a lot of money, but its purchase will cost cheaper than purchasing a tool.

If you follow the contact circle, checking the anchor, you found that the resistance between all the plates is the same, its indicators do not “jump” and there are no visible cliffs, it is necessary to conduct the next check. Measurement mode must be put on a value of 200 kom. If your measuring device does not contain such a scale, it can be set to a value of 20 kOhm. One probe of the multimeter is fixed on the mass, while others must be touched on any of the plates. Normally, when checking the anchor, the contacts should not be “nicknamed”. If you do not observe such a reaction, then your anchor does not shorten the mass. Most likely, the part is good or the presence of an interval circuit is possible.

Examples of testing anchor

Both anchors of professional tools and medium.Sized equipment can fail. Below your attention we present a specific example of checking the anchor of the Makita GA 9050 angle grinding machine. The power tool is equipped with a powerful 2000-Water collector electric motor. To verify the performance of the anchor of the Bulgarian Makita GA 9050, the contact group of part should be diagnosed directly. Before this, you need to turn on the multimeter and set the measurement mode 200 Ohms. If you have an analog digital measuring device, it is better to use it than digital. After setting a multimeter, you can proceed directly to checking the anchor.

The resistance is measured between each plate. Multimeter probes are placed on each lamella so that the recess between them is located exactly in the middle. If the part is in good condition, the resistance between each of the lamellas should be the same. The divergence of indicators most likely indicates the breakdown of contact. Of course, at home, such a malfunction will not be able to detect. If you notice the gap of the winding outside when checking the anchor, you can try to stock up on your own. Sometimes this allows you to save the situation, and the Bulgarian will serve you for some time. The absence of indicators during the examination of the plates during the check of the anchor for performance indicates their disclosure.

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Sometimes a malfunction can be seen visually. In working condition, all the plates of the contact group of the anchor should be even and smooth. In the described cases, the part cannot be repaired and requires replacement. Directly with the anchor should be changed and engine brushes. A new detail can cost a lot of money, but its purchase will cost cheaper than purchasing a tool.

If you follow the contact circle, checking the anchor, you found that the resistance between all the plates is the same, its indicators do not “jump” and there are no visible cliffs, it is necessary to conduct the next check. Measurement mode must be put on a value of 200 kom. If your measuring device does not contain such a scale, it can be set to a value of 20 kOhm. One probe of the multimeter is fixed on the mass, while others must be touched on any of the plates. Normally, when checking the anchor, the contacts should not be “nicknamed”. If you do not observe such a reaction, then your anchor does not shorten the mass. Most likely, the part is good or the presence of an interval circuit is possible.

Inspection of the mechanics of the collector engine

When repairing any electric motor, you should check the free course of the shaft, which depends on the wear of the bearings. The prolonged inertial rotation of the rotor, the absence of a rattle, creaks, radial and axial shaft beam indicates the good quality of the bearings when looking for the cause of excessive heating of the collector electric motor. Having made sure of the service of the mechanics, you can check the electrical component of the electric motor.

For example, parts of the bearing that have fused inside the electric motor or fragments from other mechanisms can damage the rotary and stator windings of the collector engine

Therefore, when analyzing the electrical appliance or power tool, you should always pay attention to the serviceability of other mechanisms, because the collector electric motor inside the case is open and unprotected from the hit of small objects that can damage it

In many power tools, the engine is not protected from small objects

Briefly about the device of collector electric motors

In collector electric motors, the magnetic fields of the stator and rotor interact at an angle that is as profitable as possible to give the shaft the moment of rotation. The rotation angle (rotor position) and at the same time switching system are collector brushes on the rotor. The system of coils with magnetic circuits creating the resulting electromagnetic field to give the moment is called an anchor.

The principle of action of a collector electric motor using a direct current engine example

In most collector electric motors, an anchor is an anchor whose electromagnetic field “clings” for magnetic fields of magnets or stator windings of excitement. Therefore, the word “anchor” is often understood as a collector engine rotor, since switching the stator windings is more complex and less effective.

Collector DC electric motors with magnets are used mainly in children’s toys and in electric drive devices of cars. To create a powerful magnetic field and a stronger torque, excitation coils are used, which are connected in several ways:

  • The sequential connection (the current of the collector and coils of excitement is equal). The advantage is a large maximum moment, which, however, can be a lack of idle, unwinding the shaft of the collector electric motor to critically high speeds;
  • Parallel connection. The advantage is the good stability of the rotor of the collector engine when changing the load on the shaft, but the maximum moment is less compared to sequential excitement;
  • Mixed excitement, in which one part of the rotor and stator windings are connected sequentially, and the other is parallel. The most popular example of the use of mixed excitement in collector electric motors is a car starter;
  • Independent excitement, in which the current of the rotor and stator collector is regulated separately. It is used in powerful collector electric motors on electric locomotives.

Schemes of connecting excitation coils in a direct current engine

Leaving aside the theory, it should be noted that the collector drives of direct current with sequential excitement can also work from alternating voltage, in fact, being a detrimental. These engines have an additional conclusion for connecting alternating voltage and are widely used in various power tools, due to the “flexible” characteristics of changes in speed and the moment of rotation.

Excitement coils and designation of a universal collector engine

The chain calls by the tester

If the visual inspection has not given obvious results, it is recommended to continue the examination using a multimeter. Having set the switching switch of the modes to the Ommeter position (200 Ohms range), it is necessary to “call” two neighboring lamellas of anchors with two probes. If the resistance on all turns is the same, this means that the windings are working. If on some pairs a tester shows another resistance or a chain break, a malfunction in this coil.

Gap of wiring can occur between the winding and the core. Carefully examine the places of connection of the coils with the lamelons of the collector in the bottom of the anchor, visually check Contact rations.

Which is more likely in a grinder.Signs of rotor combustion

As Shakespeare said: “Nothing forever under the moon”. Household appliances, alas, is not an exception. It happens that even the most reliable mechanism fails. And one must be ready to meet this fact without panic, with firm confidence that there are no hopeless situations. How a grinder is arranged, what malfunctions can be, how to check the anchor of the electric motor, determine the cause of the breakdown and eliminate the problems? Knowing the device of the main components of the power tool will allow the master with their own hands to diagnose and repair the angular grinding machine.

Factors causing the stator failure:

Signs by which you can understand that the stator is faulty:

  • The smell of burning insulation appears.
  • The case overheats.
  • Smoke appears.
  • The rotation of the shaft slows down or stops.
  • The shaft spontaneously spontaneously spaces, the tool is dramatically gaining maximum speed.

The wires of the winding are covered with a protective layer of insulating varnish. When overheating, it burns out and destroys. This causes a short circuit of the turns. The varnish at the same time makes a specific smell. The closure of only one of the wires completely disables the grinder.

Rules that will help to avoid overheating of the Ushm engine:

  • Turn off the device after working at low speeds not immediately, but after about one minute.
  • When working under load at low speeds, make frequent breaks.

Often you can avoid replacing a faulty stator by rewinding its winding. The rewinding of the spoiled coil of the stator of the grinder can be done with your own hands, but it is recommended to entrust this work to a specialist.

The device of anchor of the grinder

The motor anchor is a design consisting of a special conductive winding and magnetic wire, in which a rotating shaft is pressed. On one side of the part there is a sliding gear. On the opposite side is a collector with lamellas.

There are also special grooves in the design in which the anchor winding is laid. Its ends are in pairs connected in the lamella and as a result form a single chain.

Diagnostics of malfunctions in Ushm work

Before trying to disassemble the Ushm, you need to diagnose the breakdown. Before the final failure, the following signs may appear:

  • Strong vibration is observed;
  • Collector brushes can spark;
  • The motor may turn on with uterine buzzing;
  • Shake the rotation bearings;
  • There is a smell or smoke from the body.

Checking the electric part

The electrical part of the tool includes the following elements:

Checking the power circuits

First you need to evaluate the integrity of the network cord. There should not be damage on it. You can also include a tester in a voltmeter mode and estimate the input voltage in the Ushm. It should be 220 in.

Checking the start and control unit

Then it is recommended to test the operation of the start button. The functioning of the electronic control unit is of no small importance. Often the contacts of the circuit breaker are oxidized or clogged.

Diagnosis of the rotor. How to “call” the anchor by the tester?

To evaluate the operation of the rotor, you need to use the tester. To do this, the multimeter must be turned on for 200 Ohms and alternately evaluate the resistance of the windings. If it coincides in all areas, this indicates the integrity of the anchor. Otherwise, the element must be replaced.

Diagnosis of the electric motor stator

With the serviceability of the anchor, all manipulations are carried out with the stator. In this case, it is recommended to evaluate the resistance of the windings. When rewinding the coils, you need to use a special plywood template.

Checking the mechanical part of the machine

To identify the breakdowns of mechanical elements, it is recommended to disassemble the device case. Typically, the gearbox cover is fixed using 4 screws. They need to be unscrewed to get to a pair of gear.

Inspection of the gear of the gearbox

When examining the gear, it is necessary to evaluate the strength of the mounting of the gear. The volume of lubrication and the determination of the structure of the teeth are of no small importance.

Checking the stop button

This element is a spring.Loaded steel rod that prevents the rotation of the working shaft. The button is used when changing cutting discs. Damage is possible when jamming the disk. They also happen when the engine is turned on with a pressed button.

Officing a flange for attaching nozzles

Bulgarian disk is attached with flange threaded clamp. It differs in a simple design, therefore it breaks very rarely. When examining, you need to familiarize yourself with the state of the thread. If necessary, this part can be treated with solidol.

Checking the bearing of the rotor shaft

To evaluate the operation of these elements, they must be visually examined. Waste bearings have a plain color and easily rotate when scrolling.

How to disassemble the Ushm

When identifying the causes of the malfunction, you need to start repairing the Ushm. It is important to know how to disassemble a grinder. In this case, you need to follow the following rules:

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  • Disconnect the device from the network;
  • Place the tool on a well.Lit table or workbench;
  • Adhere to the procedure for disassembling and reverse assembly of the device.

Small breakdowns and their elimination

In cases where the Bulgarian refuses to turn on when the start button is pressed, the reason can be insignificant and, most likely, the repair can be carried out yourself without the help of a specialist. In this case, you need to be guided by the main rule. To start with the simplest knots and move to more complex. In this case, the cause of the breakdown of the grinder may be the wiring on the section of the power wire and brushes.

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First of all, you need to turn off the grinder from the network, and then inspect the cable for damage. After that, you need to disassemble the housing and check the connection of the power button and brushes. If the wire is damaged, it can be replaced with a new, and the torn electric circuit is restored. If, after checking the cable and the electric circuit, the current comes to the mechanism, but the start is not made, then the problem may be in the start button itself.

You should check the button and eliminate it if the malfunction is detected or replace the button. The button must be carefully disassembled, while it is desirable to mark the terminals and wires. When connected, it is important to correctly connect the contacts, since the wrong installation can cause blocking the winding and jamming of the anchor.

After checking the operability of the power wire and the button, you need to check the speed controller, which is available in some Ushm models. If the malfunctions are not detected, then you need to pay attention to the brushes and, if necessary, replace them, as well as clean all the contacts.

Graphite brushes are faulty

The main cause of the malfunction may be brushes. Depending on the loads and duration of the work, the brush grinds can last six months, a year or two, then worn out, and the tool may stop working. Replacing old parts with new ones is made with a cable turned off and a disassembled case. Using a screwdriver, you need to unscrew the brush holders and remove the old brushes. They can also be closed with plugs in the housing, and then the case will not have to disassemble.

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Brushes should only change to similar in size and material, and after replacing the brush is rubbed. The grinder works at idle for some time. With a faulty start button, it is forbidden to work with a grinder, as this can lead to jamming of the cutting disk, its destruction and unpredictable consequences. Speed regulator is a device for a smooth launch of a grinder, and after malfunctions in its work, it requires a replacement, since the repair will be difficult and almost impossible.

Preventive maintenance of an angle grinding machine

Unexpected breakdown can be avoided if not only visual inspection, but also the maintenance of the tool regularly. Prevention regulations manufacturer usually indicates in the passport. In order for the Bulgarian to serve for a long time and without “surprises”, it follows:

  • Timely conducting the maintenance of the tool;
  • Observe the norms of operation and storage;
  • Avoid prolonged operation of the tool under load at reduced speeds;
  • Prevent pinching of the working part of the tool;
  • Monitor the mechanisms and timely change worn parts.

18V Brushless 125mm GRINDER SHOOT-OUT. Makita, Milwaukee, DeWALT, Bosch and MORE.

Preventive disassembly, cleaning and lubrication of mechanical parts will increase the life of the tool several times. Such simple maintenance will avoid expensive repairs.

The optimal conditions for storing an angle grinding machine are dry rooms protected from sharp changes in air temperature. With prolonged preservation of the tool, it is preferable to pack it in a plastic bag in a cardboard box.

All repair work carried out with the power tool should strictly comply with safety standards. In no case should you disassemble the case when the device is included in the network. Near the place of disassembly, containers with combustible and flammable materials should not be located.

Ushm prevention

The prevention of the grinder includes compliance with passport requirements during its operation, the implementation of periodic maintenance and conducting scheduled repairs. First of all, it is necessary to strictly observe the ratio of work cycles and breaks recommended by the manufacturer. It is also necessary to periodically clean the internal space of the grinder body from dust, change the brushes in a timely manner and make the reducer lubrication. In the event of a grinder of stable vibrations and uncharacteristic sounds, an internal examination of the mechanical part should immediately carry out and carry out the necessary repair.

Unlike the usual fast.Packed nut of the grinder is a fairly expensive device. And how long it can last and whether its repair is possible in case of failure? If someone knows the answer to this question, please share information in the Комментарии и мнения владельцев.

Checking and repairing the anchor of the grinder

What wants to see the prime owner of the house in his “baggage” of power tools? Everyone, without hesitation, will answer this question for a second. Drill. And immediately adds. And, of course, Bulgarian! After all, it is she who will help to cut metal, ceramics, brick, concrete, asphalt, stone or wood; perform work on arranging niches, arched and doorways. Using this power tool, you can clean the surfaces from rust, soldering spray and influx; get rid of welds or just polish the metal to shine. The grinder will become an indispensable assistant in other types of home repairs.

Whatever the grinder (Ushm) has a reliable design, during operation, some nodes and parts fail. A breakdown of anchor working in fairly strict conditions is often the reason for the lack of normal functioning of the electric drive. In the article master plumber Consider, methods of repairing or replacing the anchor of the grinder.

The anchor of the engine of the grinder is a conductive winding and a magnetic circuit in which the rotation shaft is pressed. He has a lead gear at one end, on the other a collector with lamellas. The magnetic circuit consists of grooves and soft plates covered with varnish for isolation from each other.

In the grooves, according to a special scheme, two anchor winding conductors are laid. Each conductor makes up a half of the turns, the ends of which are paired on the lamella. The beginning of the first round and the end of the latter are in one groove, so they are closed to one lamel.

By purchasing a power tool, few people think that someday he will fail. Breakage happens to any electric tool, regardless of the price and the manufacturer’s company.

Replacing Bearings in Die Grinder

  • Club of conductors.
  • Interpretation close.
  • The breakdown of isolation to the mass is the closure of the winding on the metal case of the rotor. Occurs due to the destruction of isolation.
  • Slopics of collector conclusions.
  • Uneven wear of the collector.

The main causes of the breakdowns of the Bulgarians, including their anchors, can be considered:

check, grinder, performance, ushm
  • Mechanical wear. Brushes most often suffer.
  • Non.Compliance with the operational “passport” mode of operation. Anchor and stator.
  • Overload and voltage surges in the mains. Stator and rotor.
  • The failure of small details. Bearings, fixers, nuts, washers, etc.
  • Fall, blows and other careless attitude to the Ushm. The breakdown of the case.
  • Lack of preventive cleaning. Gearbox malfunctions or breakdown of the VCL button./Off.

If the anchor is faulty, the engine overheating occurs, the insulation of the winding is melted, the turns are shortened shortly. Contacts connecting the anchor winding to the collector plates are soldered. The current supply stops and the engine stops working.

The volume of repair work allows you to determine competent diagnosis of rotor damage. The specifics of the formation of defects that most appear when overheating of the grinder during prolonged work at increased loads allows you to determine them visually.

Standard diagnosis involves a visual analysis of the device. It is necessary to analyze the integrity of the wire and the supply of current to the motor collector. With normal feeding, you should examine the grinder from the inside. To disassemble the device will not be difficult. It is best to photograph the location of the main modules of the device when analyzing. After disassembling, conduct a visual test of the anchor on the following properties:

Prevention and maintenance

If you had to repair the grinder with your own hands, then after such an action you will definitely treat the tool more carefully and more carefully. After all, the service life of these units directly depends on how the owner takes care of them. Any tool needs care, and not only electric. Even if you leave a simple wrench in the yard in the open air, then a month later signs of rust will appear on it. The same with the power tool as grinder, they not only need to be stored correctly, but also regularly maintained.

So that the Bulgarian does not need to independently repair, it is necessary to periodically process it with lubricants, as mentioned above. To extend the service life of the unit, the following preventive measures are required:

  • Depending on the purpose of the unit (household or professional), to operate it according to the recommendations of the manufacturer, which will eliminate the need to repair the grinder with your own hands in the near future
  • Do not overload and prevent overheating
  • Regularly disassemble the case and clean the internal parts, blow them and replace grease
  • At the first signs of malfunctions, resort to repairs. You can not work with a device if you know that the mechanism is defective in it. This can not only entail a complete breakdown of the unit, but also cause dangerous consequences for the master working as a tool
  • Timely perform the replacement of consumables, parts and nodes
  • Do not work as a tool in which the button is faulty
  • If you work with an unit with a wooden process of wood, you need to be careful and very careful. The most dangerous with such actions is the return when touching the disk to the processed part. You can’t cut trees with a grinder, since it is not intended for this
  • In the process of work, keep the tool with only two hands, for which the design has a special adjustable handle
  • Use the tool only with an installed cover. Without a cover, to work strictly contraindicated by the device. There are many videos on the Internet about the consequences of incorrect work by a grinder that you can see to understand why you need to comply with safety requirements. The cover on the grinder is mobile, therefore, depending on the type of work performed, it should be correctly placed

It is necessary to store the tool in a ventilated or ventilated garage, but not in the observation pit where the condensate accumulates. Adhering to all the recommendations, it will not be difficult to repair the grinder, since the need for its repair will disappear with itself. Below watch a short and useful video on how to work correctly a grinder. This video will be useful for those who are tired of carrying out the repair of the grinder with their own hands, the need for which depends on the correct operation of the tool. Do not forget about this when you load your tool to the limit.