Purpose, features of the device and the principle of operation of the car starter

2024 Author: Erin Ralphs | [email protected]. Last modified: 2024-02-19 11:42

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

Destination

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

Hence the question of launching it arises. For this purpose, the starter was invented. Let's take a look at how it workslater. This element is able to spin the shaft using an electric motor and an external power source. The last one is a rechargeable battery. Depending on the model and type of vehicle, 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. Collector plates are pressed on it, as well as the core.
• Starter solenoid relay. The principle of its operation is extremely simple. The relay is used to supply power to the electric motor when the ignition key is turned. The relay also pushes the freewheel. The design of the element contains a movable jumper and power contacts.
• Overrunning clutch (in the common people - "bendix"). It is a roller mechanism that transmits torque through the engagement gear to the flywheel ring.
• Brushes. Serve to supply current to the starter armature plates. Thanks to the brushes, the power of the electric motor increases when it engages with the flywheel.
• Case. It is in it that all the above elements are combined. Typically, the body has a cylindrical shape. It also contains a core and an excitation winding.

All modern starters have a similar design. The differences can only be minimal. So, on cars with automatic transmission, the starter is equipped with holding windings. They serveso that the car does not start in "drive" and other modes, except for "neutral".

Types

There are several types of mechanisms:

• With gear.
• Without him.

The principle of operation of the last type of starter is in direct contact with the rotating gear. The main advantage of this design is high maintainability and resistance to increased loads.

But on most vehicles, an element with a gearbox is installed. The principle of operation of this type of starter will be discussed later. Compared with its counterpart, the gear element is more efficient, consumes less current, is small in size and maintains high performance throughout the entire period of operation.

Working principle

Since this element is powered by a battery, a prerequisite for its launch 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 very 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 principle of operation of a car starter is quite simple. First, the driver places the key in the lock and turns it to the 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 retracting winding. The relay itself may make a characteristic click. This indicates that the contacts have closed.

Further, the anchor of the retractor moves inside the housing, thereby pushing the bendix and engaging it with the flywheel crown. When the armature reaches the end point, the contacts close. Voltage is supplied to the winding of the starter motor. All this leads to the rotation of the flywheel of the engine. At the same time, the crankshaft of the motor itself rotates. A combustible mixture begins to flow into the cylinders themselves, and candles light up. Thus the motor is driven.

After the speed of the flywheel has exceeded the speed of the starter shaft, the bendix disengages. It, thanks to the return spring, is set to 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 has successfully started.

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 distinctive loud grinding sound. It occurs because the speed of rotation of the crown does not match that of 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 brief crunch can cause serious problems with the electric motor.

Starter requirements

This mechanism must meet several requirements:

• Reliability. It implies the absence of breakdowns in the next 60-80 thousand kilometers).
• Ability to start in low temperatures. Very often, the starter does not turn well at temperatures of -20 and below. But usually the cold electrolyte in the battery is to blame. To warm it up, before starting it is recommended to “blink” the high beam a couple of times.
• The ability of a mechanism to start multiple times over a short period of time.

Conclusion

So, we found out what a starter is, its principle of operation. 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.