Description of the starter. Car starter - device, principle and features of the starter. Types of modern starters

Every more or less experienced driver knows perfectly well that the starter is a device for initially starting the engine, without which starting the engine, to put it mildly, is very difficult (but not impossible). It is this element that allows you to create the initial rotation of the crankshaft with the required frequency, so it is an integral part of any modern car or other device,

Structurally, the starter is a four-pole DC electric motor. It is powered by a battery, and its power may vary depending on the car model. Most often, 3 kW starters are used for gasoline engines. Let's try to explain in more detail what a starter is: what it is, what its operating principle and structure are.

Main function

It is known that a diesel or gasoline car engine rotates due to micro-explosions of fuel in the combustion chambers. All other electrical equipment receives power directly from it. However, when stationary (turned off), the motor cannot produce either torque or electrical energy. That is why a starter is needed, which ensures the initial rotation of the engine using an external power source - the battery.

Device

This element consists of the following parts:

1. Housing (aka electric motor). This steel part houses the field windings and cores. That is, the classic circuit of almost any electric motor is used.
2. Alloy steel anchor. The collector plates and core are attached to it.
3. Starter solenoid relay. This is a device that supplies power to the electric motor from the ignition switch. It also performs another function - it pushes out the overrunning clutch. There are power contacts and a movable jumper.
4. Bendix (the so-called overrunning clutch) and drive gear. This is a special mechanism that transmits torque to the flywheel through the engagement gear.
5. Brushes and brush holders - transmit voltage to the commutator plates. At the same time, they increase the power of the electric motor.

Of course, depending on the specific starter model, its design may differ slightly. However, in most cases, this element is made according to the classical scheme and contains all the components described above. The differences between these mechanisms can be minor, and most often they lie in the way the gears are separated. In addition, in cars with an automatic transmission, the starters are equipped with additional windings, which are designed to prevent the engine from starting if the “automatic” is set to the driving position (D, R, L, 1, 2, 3).

Principle of operation

Now you understand that this is the starter in the car. It sets the starting rotation for the engine, without which the latter simply cannot start working. Now we can consider its operating principle, which can be divided into 3 stages:

1. Connection of the main drive gear to the flywheel.
2. Start the starter.
3. Disconnection of flywheel and drive gear.

The operating cycle of this mechanism itself lasts a couple of seconds, since it does not take part in the further operation of the motor. If we look at the operating principle in more detail, it looks like this:

1. The driver turns the ignition key to the "Start" position. The current from the battery circuit goes to the ignition switch and then goes to the traction relay.
2. The Bendix drive gear meshes with the flywheel.
3. Simultaneously with the engagement of the gear, the circuit is closed, as a result of which voltage is supplied to the electric motor.
4. The engine starts.

Types of starters

And although similar, the devices themselves may differ in design. In particular, they can be with or without a gearbox.

In cars with diesel engines or high-power motors, starters with gearboxes are used. This element consists of several gears that are installed in the starter housing. Thanks to it, the voltage is increased several times, which makes the torque more powerful. Starters with gearboxes have the following advantages:

1. Higher efficiency and operating efficiency.
2. Consume lower current when
3. Compact sizes.
4. Maintains high operating efficiency even when the battery charge drops.

As for conventional starters without gearboxes, their operating principle is based on direct contact with a rotating gear. The advantages of such devices are as follows:

1. Quick start of the motor due to instant connection with the flywheel crown when voltage is applied.
2. Ease of operation and high maintainability.

Recently, starter-generators, which are devices for starting an internal combustion engine and generating electricity, have become popular. In fact, a starter-generator is an analogue of commercially produced generators and starters separately.

Incorrect operation

And although many drivers understand that the starter is just a tool for starting the engine, many use it incorrectly. In particular, situations are common when, after starting the engine, the driver still holds the key in the ignition switch in the “Start” position. It should be understood that the current consumed by the starter during operation is 100-200 amperes, and in cold weather it can reach 400-500 amperes. That is why it is not recommended to hold the starter for 10 seconds or more. Otherwise, the bendix may spin up too much, heat up and jam.

Drivers also often use the starter as an electric motor in cases where there is no gasoline in the tank. They simply engage first gear and turn the ignition key. The car starts and even drives only thanks to the work of the starter. In this way you can drive 100-200 meters, but this will completely “kill” the starter.

In general, the starter should work for 3-4 seconds maximum. If the engine starts within 10 seconds, then there is clearly something wrong with the system.

Conclusion

Now you understand what this element is in a car and how it works. By the way, it should not be confused with a plant, as women do. It is worth understanding that a violet starter is a plant, and a car starter is an element for starting an internal combustion engine.

The car needs to be cranked several times. On the first machines this was done manually. But now all cars are equipped with starters that allow the shaft to rotate without any effort. The driver only needs to insert the key into the lock and turn it to the third position. Then the engine will start without any problems. What is this element, what is the purpose and principle of operation of the starter? We will talk about this in our article today.

Purpose

Due to crankshaft revolutions, the engine produces the energy necessary to move the car. But the problem is that when stationary, the motor cannot produce any power.

This raises the question of its launch. The starter was invented for this purpose. We'll look at how it works a little later. This element is capable of spinning the shaft using an electric motor and an external power source. The latter uses a rechargeable battery. Depending on the model and type of car, the starter power may vary. But for most passenger cars, a 3-kilowatt electric motor is sufficient.

Device

The design of this element includes several parts:

• Starter anchor. Made from alloy steel. The collector plates are pressed onto it, as well as the core.
• Starter solenoid relay. Its operating principle is extremely simple. The relay is used to supply power to the electric motor when the ignition key is turned. The relay also pushes out the overrunning clutch. The design of the element contains a movable jumper and power contacts.
• Overrunning clutch (in common parlance - “Bendix”). It is a roller mechanism that transmits torque through the engagement gear to the flywheel crown.
• Brushes. Serve to supply current to the starter armature plates. Thanks to the brushes, the power of the electric motor increases at the moment it engages with the flywheel.
• Frame. It is in it that all of the above elements are combined. Typically the body is cylindrical in shape. Inside it there is also a core and an excitation winding.

All modern starters have a similar design. The differences may be only minimal. So, on cars with an automatic transmission, the starter is equipped with retaining windings. They serve to prevent the car from starting in “drive” and other modes except “neutral”.

Types

There are several types of mechanisms:

• With gearbox.
• Without him.

The operating principle of the latter type of starter is direct contact with a rotating gear. The main advantage of this design is its high maintainability and resistance to increased loads.

But on most cars an element with a gearbox is installed. The operating principle of this type of starter will be discussed below. Compared to its analogue, the gear element has a higher efficiency, consumes less current, is small in size and maintains high performance characteristics throughout the entire period of operation.

Principle of operation

Since this element is powered by a battery, a prerequisite for starting it is the presence of a voltage of 12V or higher in the network. As a rule, when starting the starter, the voltage “sags” by 1-1.5V, which is quite significant. In this regard, it is not recommended to turn the starter for a long time (more than five seconds), since you can easily discharge the battery. The operating principle of a car starter is quite simple. First, the driver places the key in the lock and turns it to its extreme position. This will start the ignition system. To start the starter you need to turn the key again. At this time, the contacts will close and the voltage will pass through the relay to the pull-in winding. The relay itself may make a characteristic click. This indicates that the contacts have closed.

Next, the armature of the retracting element moves inside the housing, thereby extending the bendix and engaging it with the flywheel crown. When the armature reaches the end point, the contacts close. Voltage is supplied to the starter motor winding. All this leads to rotation of the engine flywheel. At the same time, the crankshaft of the engine itself rotates. The combustible mixture begins to flow into the cylinders themselves, and the spark plugs light up. In this way the motor is driven.

After the flywheel rotation speed exceeds the starter shaft rotation speed, the bendix disengages. Thanks to the return spring, it is installed in its original position. At the same time, the key in the lock returns to its original position. The power supply to the starter is cut off.

Thus, the principle of operation of the starter (including VAZ) is aimed at short-term rotation of the flywheel, due to which the internal combustion engine is started. The element stops working as soon as the engine starts successfully.

What happens if you do not turn off the starter while the engine is running?

Often such problems are observed when the return spring fails. If the starter continues to rotate with the flywheel, you will hear a characteristic loud grinding noise. It occurs because the speed of rotation of the ring does not coincide with that produced by the starter gear (the difference is 2 or more times). This can also happen due to a broken ignition switch.

Note that such a process is very harmful for the gears and for the starter as a whole. Even a short-term crunch can cause serious problems with the electric motor.

Starter requirements

This mechanism must meet several requirements:

• Reliability. This assumes no breakdowns in the next 60-80 thousand kilometers).
• Ability to start in low temperature conditions. Very often the starter turns poorly at temperatures of -20 and below. But usually the culprit is cold electrolyte in the battery. To warm it up, it is recommended to “blink” the high beams a couple of times before starting.
• The ability of the mechanism to be started repeatedly within a short period of time.

Conclusion

So, we found out what a starter is and its operating principle. As you can see, this is an integral element of any modern car. If it fails, it will be possible to start the engine only “from the pusher” (and on cars with automatic transmission it is completely impossible). Therefore, you need to monitor its condition and not ignore breakdowns.

The starter is an electromechanical device. This suggests that the principle of operation of the starter is to use the electrical energy of the battery and convert it into mechanical energy.

Internal structure of the unit:

The starter is divided into 5 main elements:

1. The body is made of steel and is shaped like a cylinder. On the outer wall there are 4 field windings (usually there are 4 or more) and cores (aka “poles”). Everything is held together with screw connections. The screw is twisted into a core to press the winding against the wall. The body has special holes for fastening the front part of the device, where the overrunning clutch moves.
2. The armature is an axis made of special steel onto which the armature and commutator plates are pressed. The cores have special grooves for laying armature windings. The ends of the winding are fixed to the collector plate. The collector plates are located on a circle and mounted on a dielectric platform. The diameter of the core depends on the diameter of the body. The anchor is secured to the front and back covers using bushings made of copper and steel. Bushings are also bearings.
3. The traction relay is installed on the body of the device. In the rear part of the power relay housing there are contacts - “nickels”, a movable jumper contact made of soft metal. “Pyataks” are simple bolts driven into the cover of the traction relay. Using nuts, the battery power wires, as well as the wires of the positive brushes, are put on it. The core is connected to the overrunning clutch using a rocker arm called a Benedix (the name comes from the name of the American engineer Benedix who created it).
4. The Benedix is ​​tightly mounted on the shaft and is a roller mechanism connected to a meshing gear in the flywheel crown. When torque is applied to the Benedix, the cage rollers move out of the grooves, firmly fixing the gear to the outer race. Rotating in the opposite direction, the rollers enter the separator, and the gear begins its rotation, independent of the outer race.
5. Through the brush holder, direct voltage is applied to the copper and graphite brushes, which is transferred to the armature commutator plates. In appearance, the brush holder is a dielectric cage with metal inserts, and the brushes are located inside it. The brush contacts are welded to the point plates. The pole plates are the tails of the field windings.

In order for a car engine to be able to start, the following processes occur in its depths:

• after closing the contacts in the ignition switch, the current is directed through the starter relay to the pull-in winding of the traction relay;
• the armature of the retractor relay, moving inside the housing, pushes the bendix out of the housing and engages its gear with the flywheel ring;
• when the armature of the retractor relay reaches the end point, the contacts close and current flows to the holding winding of the relay and the winding of the starter motor;
• The rotation of the starter shaft causes the machine engine to start. After the speed of rotation of the flywheel exceeds the speed of rotation of the starter shaft, the bendix disengages from the ring and is set to its original position using a return spring;
• When the key in the ignition switch returns to the first position to start the engine, the supply of electricity to the starter is stopped.

Among the starter malfunctions, the following should be noted:

• turning on the starter does not develop the required engine speed (it turns slowly);
• turning on the starter provokes the grinding of the starter gear, which is not engaged;
• the starter is not activated;
• the starter armature rotates, but the unit does not turn the crankshaft;
• The starter does not turn off after starting the engine.

The reasons for these problems are:

• poor starter connection or weak starter pole connection;
• inappropriate oil in the engine crankcase;
• battery failure or discharge;
• poor brush contact or loose wire ends;
• short circuit in the starter windings;
• the drive moves heavily along the shaft;
• the teeth of the flywheel ring have become unusable;
• the travel of the drive gear and the closing moment of the switch contacts is not adjusted properly;
• there is no contact when the ignition is turned on or the ignition switch has become unusable;
• the starter drive buffer spring is weakened;
• blocking the drive on the armature shaft;
• burning of relay contacts or its unsuitability for operation;
• bearing wear;
• the drive gear is “late” to disengage from the ring gear.

Only timely diagnostic measures, as well as high-quality, professional service will prevent such incidents, and if this has already happened - use the services of specialists from our StarteR Service Center.

Signs and causes of starter malfunction:

Question: why doesn't the starter turn on?

Answer: The contact connections may be broken, something has broken in the starter circuits, or the cause may be a short circuit. In addition, there may be a problem inside the traction relay.

Question: Where does the clicking sound come from when starting the starter?

Answer: The cause may be a discharged battery, loose contacts in the starter circuit, or a malfunction of the traction relay winding.

Question: Why does the armature not rotate when the starter is turned on, and if it does rotate, it is slow?

Answer: This happens mainly due to a discharged battery. In addition, the reasons may be burnt contacts of the traction relay, broken contact connections, a dirty commutator, old brushes, or a short circuit may have occurred in the windings.

Question: What is the reason for the ignition switch sticking in the Start position?

Answer: Most likely, the bendix did not come out of the clutch that was with the flywheel. The motor spun the starter armature, causing the starter to burn out.

Question: Why does the ignition always stick?

Answer: The reason is the starter working after starting the engine. There is no point in repairs, because the starter will break anyway.

Question: What is the secret to quick starter wear?

Answer: when the engine starts, the starter armature rotates at a frequency of one and a half thousand per minute; due to a couple of extra seconds, the number of revolutions increases by about 5 thousand. Therefore, the life of bushings, brushes, bendix, forks and commutators is exhausted faster.

Question: Why didn't the starter turn off after starting the engine?

Answer: The cause may be a malfunction of the freewheel in the starter or the contacts inside the traction relay are caked.

Question: What happens if the starter armature rotates when turned on, but the flywheel remains stationary?

Answer: all due to damage to the teeth of the flywheel or drive gear, problems with the lever, loose fastenings to the clutch housing starter, slipping of the device clutch, or problems with the drive ring.

Question: What is the reason for loss of starter power in a warm car?

Answer: such a loss is hidden:

• in mounting bolts;
• in mounting locations;
• among rotten power wires under the braid;
• in oxidized areas where wires and contact terminals are compacted;
• on rusty mounting bolts and nuts.

Instructions for use:

It must be remembered that the starter is a powerful electric motor, but only of short duration. Don't forget about this, try to follow the important instructions:

Turn on the starter for no more than 10 seconds. If the car engine does not start, leave the starter alone for 30 seconds, as it cools extremely slowly. After 2-3 unsuccessful engine starts, take a 4-minute break.

Watch the contacts in the battery terminals. It often happens that the terminals oxidize and the starter does not accept the current it needs, as a result of which it does not develop sufficient torque. The engine does not start, and instead of cleaning the terminals, we take the unit in for repair. Of course, the masters will explain the reason, but the time is wasted.

After starting the engine, turn off the starter. If this is not done, then 2-3 seconds will simply destroy the node. After all, when starting the engine, the starter armature has a rotation speed of 1500 rpm, and after starting, the armature will begin to rotate at a speed many times greater (if the bendix is ​​engaged with the engine flywheel). An increase in speed will lead to increased wear on all starter parts, which will lead to complete destruction of the unit. Watch this moment, do not allow such meaningless rotation. The same effect is inherent in the case of malfunctions of the ignition switch.

Do not move the vehicle using the starter. It is worth considering that the lower the speed, the more current flows to the starter windings. If you put the car on the handbrake, engage the gear, and then turn on the starter, then after 30 seconds of such madness the windings of the assembly will simply burn out, and the battery will also become unusable.

Take care of your car, and it will come to your aid more than once.

Having gone through a long path of formation and development, modern vehicles have a lot of improved systems and mechanisms, the details of which are subject to greater and greater demands. For example, a car starter... Everyone knows about its exceptional importance in terms of the full functioning of the car, therefore, it is often the subject of special concern for the car owner, especially if he is the happy owner of the latest model with a built-in automatic transmission (in the event of a starter failure, use using a crank to start the engine, as owners of outdated brands do, will no longer work). Based on the particular importance of the issue, we considered it necessary to consider in more detail the types of starters, the design and principles of their operation, as well as possible malfunctions and ways to eliminate them.

Types and purpose of starter

A car starter is presented in the form of a small four-band electric motor that provides the initial rotation of the crankshaft. It is needed to maintain the required rotation speed, which most directly affects the further start of the internal combustion engine. Often, starting a medium-cylinder gasoline engine requires the presence of a starter with approximately 3 kW of electricity. The starter can be called a DC motor that receives energy from the battery. The voltage taken from it, with the help of four brushes (an integral part of any starter), significantly increases the power of the electric motor itself. All electromagnetic motors of this kind existing today are divided into two main groups: those with a gearbox and those without one.

Many experts advise using a starter with a gearbox, which is argued by its reduced current requirement. In other words, devices of this type will be able to ensure efficient rotation of the crankshaft even when the battery charge is low. Another advantage of using a starter with a gearbox is the presence of permanent magnets in its design, which significantly reduce the possibility of problems with the winding of the device. True, if you look from the other side, the likelihood of a rotating gear breaking, on the contrary, increases. As a rule, this scenario most often occurs due to a manufacturing defect or in the case of low-quality production.

Starters without a gearbox have a direct effect on gear rotation. In this case, owners of vehicles with such a system benefit from the simplicity of the device’s design, which makes them easier to repair. In addition, immediately after applying current to the electromagnetic switch, the gear is instantly connected to the flywheel, which ensures fairly fast ignition. Also, do not forget about the high endurance of such starters, especially since the likelihood of breakdown due to the influence of electricity is practically reduced to zero. However, in the operation of starters that do not have a gearbox, not everything is so perfect and there is a possibility of operational failures at low temperatures.

How does the starter work?

In fact, the design of the starter is not particularly complicated, and the main components are the electric motor, armature, retractor relay, overrunning clutch (Bendix), and brush holders.

Frame(electric motor) is presented in the form of a cylindrical steel part. Excitation windings (usually there are four of them) and cores (poles) are attached to its inner wall. Fastening is carried out by means of a screw connection, in which the screw is screwed into the core, which, in turn, presses the winding against the wall. Also, in the body there are threaded technological holes, with the help of which the front part is fastened, where the overrunning clutch moves.

Anchor– the part is made of alloy steel and has the shape of an axis. The core and collector plates are pressed onto it. The core design contains special grooves designed for laying armature windings, the ends of which are securely attached to the collector plates. The collector plates, in a circular pattern, are mounted on a dielectric base. The diameter of the core and the internal diameter of the housing (together with the windings) are directly related to each other. The armature is fastened to the front and rear covers of the starter using brass (less often copper) bushings, which simultaneously act as bearings.

Solenoid (or traction) relay used to transfer power from the ignition switch to the starter motor, while performing another important task - pushing out the overrunning clutch. In the rear part of the retractor relay housing there are power contacts called “nickels”, as well as a movable jumper contact made of soft materials. “Pyataki” are ordinary bolts pressed into the ebonite cover of the traction relay. Using nuts, power wires coming from the battery and the “positive” starter brushes are connected to them. The traction relay core and the overrunning clutch (better known as the “Bendix”) are connected to each other through a movable “rocker arm”.

Overrunning clutch(Bendix) is a movable roller mechanism mounted on the armature shaft. One of its main tasks is to transmit torque to the flywheel crown, using a special meshing gear for this purpose. After starting the engine, it disconnects the flywheel crown and the drive gear, thereby ensuring stable operation and safety of the starter. The entire structure is assembled in such a way that when torque is transmitted to the bendix in one direction, the rollers located in the separator come out of the grooves and rigidly fix the gear to the outer race. When rotation occurs in the opposite direction, the rollers “hide” in the separator and the gear can rotate regardless of the outer race.

Brush holders and brushes provide operating voltage to the armature commutator plates. The brush holder is presented in the form of a dielectric cage having metal inserts located inside. Using spot welding, the brush contacts are welded to the pole plates, which, as a rule, are the “tails” of the field windings. By performing the main operating cycle of the starter, brush holders increase the power of the electric motor.

The designs of most starters are similar to each other and necessarily include all of the above components. If there are differences, they are insignificant and, most often, relate to the automatic unlocking mechanism of the gears. Also, the starter for cars with automatic transmissions has additional retaining windings designed to prevent the engine from starting when the selector is installed in any of the travel positions. The difference between different starter models lies in their size, power and supplied voltage. So, for example, if a 12 V battery is enough to operate a passenger car starter, then for a heavy truck starter this will not be enough and you need to use 24 V.

Starter operating principle

The entire working process of a car electric starter is conventionally divided into three stages: on the first - the drive gear is connected to the flywheel ring; in the second, the starter starts, and the third stage involves the disconnection of the drive gear and flywheel. The starter's operation is short-term, since after performing its main function (transmitting torque to the engine), it no longer participates in the further movement of the car. The detailed operating principle of the starter looks like this: When the driver turns the ignition key to the starting position, current from the battery is transferred to the ignition switch and then to the traction relay.

After this, the bendix drive gear (overrunning clutch) moves and connects to the flywheel, which helps close the circuit and subsequently supply voltage to the electric motor. As a result of the described actions, the car engine starts, and after its speed begins to exceed the speed of the starter itself, the overrunning clutch disconnects the drive gear from the electric motor shaft. That's it, until the next start of the power unit, the starter may not strain.

Possible starter malfunctions

Like any other mechanism in a car's design, the starter cannot work properly all the time. Of course, it is subject to much less load than, say, the same internal combustion engine, however, it cannot completely avoid breakdowns. There may be several reasons for each individual malfunction, and in order to understand the problem in detail, it is impossible to do without a thorough diagnosis. We'll talk about repairing the starter a little later, but now let's take a more specific look at all the possible malfunctions of this important device.

And so, for starters, the starter may simply not turn on. The reasons for this phenomenon may be:

- breakdown of the starter relay (winding breakage, wedging, displacement of the contact disk);

Lost power circuit contact (possibly due to loose wires or internal corrosion); - winding short circuit;

Lack of contact in the mechanism responsible for turning on the ignition.

Also, slow rotation of the crankshaft is considered a problem in operation, even if the starter has started. The presence of this malfunction may be due to the increased viscosity of the filled oil, which does not correspond to the season; problems with the battery (breakage or discharge); oxidation of battery cable terminals, loose terminals or poor brush contact.

Sometimes it happens that the armature seems to be rotating, but for some reason the crankshaft does not rotate. In this case, the causes of the malfunction may be hidden in the towing of the freewheel of the drive or in the difficulty of moving the drive along the screw thread of the shaft.

Another malfunction that often occurs in the operation of the starter is the grinding of a gear that cannot engage. This happens as a result of the formation of holes in the teeth of the flywheel ring, or as a result of incorrect adjustment of the moment of closing the contacts of the switch and the drive gear. Also, one of the possible causes is a weakening of the drive buffer spring.

Of course, the starter not starting is a problem, but running too long when the engine has already started but the starter is still spinning is also considered a malfunction. In this case, it can be assumed that there is a problem in the ignition switch (it is stuck); short circuit of the relay winding or jamming of the drive located on the armature shaft. In addition, sintered contacts of the traction relay also lead to a similar malfunction.

If during the starter operation you notice an increased noise level, this may be a consequence of the following malfunctions:

- the drive gear comes out of engagement with the ring gear with a delay;

The starter fastenings have become significantly loosened;

The tightness of the starter pole fastening decreased and the anchor began to catch on it.

Starter repair

So, let’s imagine that you have discovered one of the above-mentioned signs of a starter malfunction. Naturally, the first step towards eliminating it will be to conduct a full diagnosis in order to determine the exact location of the breakdown. To begin with, it is worth checking the wiring, or rather the wires going from the battery to the starter and the wire passing through the relay from the ignition switch. Perhaps it is in this part that the malfunction lies. If everything is in order with the wires and the relay, then you will have to dismantle the starter itself.

In each individual car model, the described part may differ in size, method of fastening or location, but despite this, the operating principle of all of them is almost the same.

Note! To carry out a detailed inspection and subsequent repair work, dismantling the starter must be carried out without fail. The step-by-step instructions for removing the starter are as follows:

1. Disconnect the battery (do not touch the starter until this point, as this may cause a short circuit);

2. Unscrew the current-carrying electrical cables from the starter terminals and the traction relay studs; Remove the engine protection;

3. Unscrew the starter mounting bolts;

4. Remove the starter by lifting it up.

Once the device is in your hands, you should check its functionality. To carry out this operation you will need a charged battery: the ground must be connected to the body, and the positive wire to the contact bolt If the relay is working properly, the bendix (overrunning clutch) will be extended to the front. If, after connecting, the starter still does not work, we can safely talk about a faulty brushes or a burnt-out winding, but usually the problem is still in the brushes.

The next step towards fixing the problem is disassembling the device. To accomplish this, you need to unscrew the two fastening bolts, after which the body, along with the anchor and brushes, is removed. At the same time, you can inspect the gearbox: to do this, remove the protective cover and perform a visual diagnosis. If everything is fine, lubricate the gears with grease, close the lid and put it all aside.

Now pick up the electrical part of the starter, which, according to the results of the preliminary inspection, needs repair, pull the brushes and armature out of the housing. To remove them, simply press your finger on the axle and since it is held only by a magnetic field, it should come out without problems. Then, using a Phillips screwdriver, unscrew the two screws and remove the top cover (there is a washer and retaining ring underneath).

After everything has already been unscrewed, you need to remove the back cover, inspecting the bushing located there - it is also often a weak point in the starter. When the bushing wears out, the axle becomes warped and it is difficult for the starter to turn the engine, or it does not turn it at all. At every maintenance or repair, experts recommend replacing all bushings.

An important part of the starter design is the brushes, and if they wear out too much, the device will definitely not work. Therefore, when disassembling the starter, be sure to pay attention to them, and if the inspection confirms the preliminary diagnosis, then it is better to replace the broken parts with new ones. It is very difficult to restore such brushes (a very strong soldering iron is required), so it is easier to buy a new block. Note! Inside the brush block there is a plastic sleeve that helps keep the brushes compressed. Under no circumstances should it be pulled out, otherwise you will complicate the subsequent procedure of putting the block on the anchor.

Now let's move on to inspecting the starter rotor (armature). If you notice dirt or any other debris in its grooves, they can be cleaned using a metal file or a thin flat screwdriver. It is better to clean the surface adjacent to the brushes and level it with fine sandpaper. After all the specified stages of work are over, reassemble the starter in the reverse order and check its functionality: if it works, then we install it back on the vehicle.

During the process of reassembling the starter, do not forget to treat all its moving parts (gearbox, bushings) with lubricant. Remember! To ensure that the starter does not fail at the most inopportune moment for you, it is necessary to carry out its technical inspection at least once a year, followed by maintenance. Maintenance consists of all of the above measures, after which the starter power increases and the amount of current consumed for operation decreases. As a result, starting the engine in the cold season is significantly easier.

To successfully start an internal combustion engine, you need a device that will give the crank mechanism an initial impulse, that is, it will rotate the flywheel to the required speed. The starter is such a device and is responsible for starting the engine. In this article we will consider in detail the design and operating principle of a car starter, as well as its possible malfunctions.

Starter device

The car starter is an electric motor. It converts electrical energy from the battery into mechanical work, which drives the flywheel and crankshaft to begin the process of moving the pistons. All engines are equipped with a starter.

Car starter

The principle of operation of the device is based on the laws of physics, which are known from school. If you place a wire frame with two ends between the two poles of a magnet and then pass a current through it, it will begin to rotate. This is the simplest electric motor.

A simple car starter consists of a metal case containing four magnetic cores (shoes). These magnets in the housing represent electric motor stator. Previously, an excitation winding was wound on the shoes, to which electric current was supplied from the battery. That is, it was a classical electromagnet. Modern devices use conventional magnets.

Another important part of the device is anchor. It is a shaft with a pressed core made of electrical steel. In the grooves of the core there are the very frames that will rotate around the poles of the magnet. The ends of the frames are connected to a commutator, to which four brushes fit - two positive from the battery and two negative, which will go to ground.

The closing back cover contains brush holders with springs that constantly press the brushes towards the commutator to ensure contact. Also installed in the rear cover is an armature support sleeve or bearing.

There is an input contact on the metal case. The positive terminal of the battery (+) is connected to this contact. The current passes through the armature frames and exits to the negative mass brushes. Ground is connected to the negative terminal of the battery. Thus, a magnetic field is created around the armature frame and it rotates.

The positive battery wire that goes to the starter is much thicker than the others. This wire carries a starting current of approximately 400A.

Current from the battery to the starter cannot be supplied continuously. It is only needed when the engine starts. Therefore, between the positive wire of the battery and the starter contact there is a so-called copper penny that closes the contacts.

There is also a spline connection on the armature shaft, on which there is a guide bushing and bendix with a gear with the possibility of axial movement. This movement ensures that the gear contacts directly with the flywheel ring gear. In simple words, we can say that Bendix approaches the flywheel, turns it as much as necessary, and then moves back.

But the bendix does not move along the shaft on its own. This makes another smaller electromagnet - solenoid relay. A fork fits from the relay to the gear, which pushes the bendix. The retractor coil is supplied with control current from the battery through the ignition switch. When the ignition is turned on, the coil is magnetized and retracts the core. This core, on the one hand, is connected to the Bendix fork, and on the other, to the nickels that close the contacts of the electric motor. When the voltage from the solenoid relay coil is removed, the plug is pulled back into place and the electric motor stops working.

The armature begins to rotate only when the gear has already engaged with the flywheel.

Main Components

Thus, the main components of the starter can be called:

• magnetic stator;
• shaft with anchor;
• solenoid relay with components (electromagnet, core, contacts);
• brush holder with brushes;
• bendix with gear;
• fork;
• body elements.

Principle of operation

Considering the design of the starter, let's consider its operation step by step:

1. The driver turns on the ignition and control voltage is supplied to the solenoid relay. The relay coil becomes magnetized and moves the core.
2. The core brings the bendix and gear to the flywheel using a fork and at the end of its stroke closes the contact pins to the electric motor.
3. The starting current is supplied to the armature winding, which begins to rotate in the magnetic field of the stator. The starter started working.
4. The engine started and the driver turned the key from the start position. The control current stopped supplying the solenoid relay, the nickels opened, and the bendix and gear returned to their original position under the action of the return spring. The starter has stopped working.

Bendix device

Bendix is ​​a rather interesting device. It is sometimes called a freewheel or freewheel.

To start the engine, the flywheel must rotate no slower than 100 rpm. Since the starter gear is much smaller than the flywheel ring gear, it needs to spin 10 times faster to give the flywheel the required acceleration. This is 1000 rpm.

When the engine starts, the flywheel begins to rotate very quickly. It transmits this rapid rotation to the gear. It is easy to calculate that the gear rotation speed will already be 10,000 rpm. If such acceleration was transmitted to the starter shaft, it would not be able to withstand it. This is exactly what Bendix is ​​for. It transmits rotation from the gear to the flywheel, but does not transmit it back from the flywheel to the gear.

The Bendix itself consists of two parts: the gear and the housing. The inner race of the gear fits into the housing with the outer race. Inside this clip there are four rollers with springs. The bendix housing rotates through the starter shaft. When rotating, the inner race of the gear seems to jam in the housing and rotates, and when the gear rotates from the flywheel, these rollers diverge and do not transmit rotation to the shaft. The starter shaft itself rotates at the same speed.

Types of starters

As described above, modern starters do not use shoes with an excitation winding, but magnets. Magnets as a stator can significantly reduce the dimensions of the device. In this case, the rotation speed of the armature increases. Therefore, a gearbox is sometimes used.

Based on this, starters are divided into:

• gear;
• simple (gearless).

We have already become familiar with the structure and operation of a simple starter. The operation of a gearbox is based on the same principles as a simple one, but has a slightly different device. The torque from the armature first goes to the planetary gearbox, which converts it, and then to the bendix shaft. Rotation from the armature to the gear is transmitted through the planetary gear carrier.

This type of starter has the following advantages:

• higher efficiency;
• less current consumption;
• small sizes;
• starting the engine even when the battery charge is low.

But this design affects the complexity of repairs.

Basic faults

All possible types of starter malfunctions can be divided into mechanical and electrical.

Mechanical components may be associated with:

1. Contact pads sticking.
2. Wear of bearings and retaining bushings.
3. Wear of bendix rollers.
4. The plug or the solenoid relay core is jammed.

Electrical problems:

1. Production of brushes and commutator plates.
2. Open circuit in the winding of the shoes (stator) or the solenoid relay.
3. Short circuit and burnout of windings.

The brushes and solenoid relay cannot be repaired. These parts are replaced with new ones. It is better to entrust winding repairs to a qualified auto electrician.

The starter is a rather complex mechanism that requires attention from the driver. It is better to eliminate any noises and rattles promptly. But despite the overall complexity of the device, the principle of its operation is very simple. Once you understand it, you can fix many problems yourself.