The working principle of Starter
One electromagnetic switches
The motor by magnetic field (stator) and the armature (rotor) and commutator, in order to increase the torque by 4 magnetic multipole magnetic field, are common. When the current passes through the armature coil, the whole coil is turned by a torque. As the DC motor is energized, it will produce a back electromotive force, and is proportional to the engine speed, and torque is inversely proportional, so it can meet the requirements of engine starting. The starting current of the starter is large, so the operation time must be short.
1. electromagnetic switch structure features
The electromagnetic switch is mainly composed of two parts: an electromagnet mechanism and an electric motor switch. The electromagnet mechanism is composed of a fixed core, a movable core, an attracting coil and a retaining coil. The fixed iron core is fixed, and the movable core can be axially moved in the copper sleeve. The front end of the movable iron core is fixed with a push rod, and the front end of the push rod is provided with a switch contact plate, and the back section of the movable iron core is connected with the shifting fork with an adjusting screw and a connecting pin. A reset spring is arranged outside the copper sleeve to reset the movable parts such as movable iron core. The arrangement position of the terminals of the electromagnetic switch is shown in the diagram
2. electromagnetic switch working principle
When attracting winding and holding coils generates a magnetic flux at the same direction, the electromagnetic force are superimposed on each other, can attract the movable iron core moving disc contact until the front end of the push rod will be connected to the electric switch contact potential motor main circuit is switched on so far.
When attracting winding and holding coils generated magnetic flux in the opposite direction, the electromagnetic force to offset each other, under the action of the reset spring, the plunger movable component automatic reset, touch disc and contact disconnect motor main circuit disconnect.
Two 、 starting relay
The structural diagram of the starting relay is shown in the upper left corner of the relay, consisting of an electromagnet mechanism and a contact assembly. The coil are respectively connected with the casing on the ignition switch terminal and ground terminal "E" connection, the fixed contact and starter terminal "S" connection, movable contact arm and the bracket by contact with the battery terminal "BAT". The starting relay is a normally open contact, and when the coil is energized, the relay core generates electromagnetic force to close the contacts so that the relay controlled attraction coil and the holding coil circuit are switched on.
1. control circuit
The control circuit comprises a starting relay, a control circuit and a starter electromagnetic switch control circuit.
The starting relay control circuit is controlled by an ignition switch, and the controlled object is a relay coil circuit. When the ignition switch is switched on, the current moves from the accumulator battery through the starter power terminal to the ammeter, from the ammeter to the ignition switch and the relay coil back to the battery negative. Thus, the relay core generates strong electromagnetic attraction, which is the control circuit for closing the relay contact and switching on the electromagnetic switch of the starter.
2. main circuit
As shown in the arrow, when the electromagnetic switch is switched on, the coil 3 is attracted and the holding coil 4 generates a strong electromagnetic attraction, and the main circuit of the starter is switched on. Circuit for:
Battery positive, starter power terminals, electromagnetic switch, excitation winding and armature winding to ground, the negative battery produces electromagnetic torque, so the starter, starting the engine.
One. Introduction of starter
The starter is composed of a DC series motor, a control mechanism and a clutch mechanism. It specifically starts the engine and needs a powerful torque, so it has to pass a great amount of current and reach several hundred amperes.
DC motor at low speed, torque, high speed, torque gradually smaller, it is suitable for starter.
The starter adopts a DC series motor, and the rotor and stator parts are made of coarse rectangular cross section copper wire; the drive mechanism adopts a reduction gear structure; the control mechanism adopts an electromagnetic magnetic suction mode.
Two. Electric mechanismThe motor by magnetic field (stator) and the armature (rotor) and commutator, in order to increase the torque by 4 magnetic multipole magnetic field, are common. When the current passes through the armature coil, the whole coil is turned by a torque. As the DC motor is energized, it will produce a back electromotive force, and is proportional to the engine speed, and torque is inversely proportional, so it can meet the requirements of engine starting. The starting current of the starter is large, so the operation time must be short.
Three 、 reduction mechanism
The driving gear of the reduction gear mechanism is connected with the engine flywheel to start the engine, and adopts a one-way drive mode. When the speed of the pinion gear on the motor is higher than the speed of the flywheel ring of the engine, the motor drives the engine to rotate, and when the engine speed is higher than the motor, the power transmission relationship between them is automatically lifted.
The deceleration starter mainly consists of electromagnetic meshing switch, reduction gear, motor, starting gear (pinion) and one-way meshing device, as shown.
Four, institutional features
P11C engine deceleration starter has the following salient features:
The power output structure is divided into two parts: the armature shaft and the transmission shaft. The two ends of the armature shaft are supported by a ball bearing, the load distribution is uniform, the use time is long, the abrasion is not easy, the armature is shorter, and the armature shaft bending is not easy to occur and the winding of the magnetic field is not worn.
Using the deceleration device between the rotor and the starting gear, installation of gear, motor starting torque transmitted to the starting gear will increase. By using electromagnetic switches, the power output of the motor (after the reduction gear) is the starting gear and the starting gear shaft, while the part of the clutch does not move. The starter with small output power often adopts the external meshing method, and the starter with large output power adopts the internal engagement mode.
Slow down starter is operated by electromagnetic switch, and some are equipped with auxiliary switch (or vice switch). Its role is to prevent the electromagnetic switch and switch burn (starting switch). The power consumption of the starter is greatly reduced by classifying and switching on the power supply, thereby prolonging the service life of the starter.
The volume and weight of the deceleration starter is about half of that of the traditional starter. It saves the raw materials and is easy to assemble and repair.
The deceleration starter starter poles with the traditional method, but the magnetic field coil winding is often used a small wire winding armature winding in series, although with the traditional principle is the same, but the advanced manufacturing technology.