The control device of Automotive Motor
includes electromagnetic switch, starter relay and ignition starter switch light components, and the electromagnetic switch is made together with the starter.
1. Electromagnetic switch
1. Structural characteristics of electromagnetic switch
The electromagnetic switch is mainly composed of an electromagnet mechanism and a motor switch. The electromagnet mechanism is composed of a fixed iron core, a movable iron core, an attracting coil and a holding coil. The fixed iron core is fixed and the movable iron core can move axially in the copper sleeve. A push rod is fixed at the front end of the movable iron core, a switch contact plate is installed at the front end of the push rod, and the rear section of the movable iron core is connected with the shift fork by an adjusting screw and a connecting pin. A reset spring is installed on the outside of the copper sleeve to reset movable parts such as the movable iron core. The arrangement position of the terminals of the electromagnetic switch wiring is shown in the figure
2. Working principle of electromagnetic switch
When the magnetic flux generated by the attracting coil and the holding coil are in the same direction, their electromagnetic attraction forces are superimposed on each other, which can attract the movable iron core to move forward until the contact disk at the front end of the push rod turns on the electric switch contact potential. The main circuit of the motor is connected. .
When the magnetic pain generated by the attracting coil and the holding coil are in opposite directions, their electromagnetic attraction cancels each other out. Under the action of the return spring, the movable iron core and other movable parts are automatically reset, the contact plate is disconnected from the contact, and the main circuit of the motor is disconnected. .
2. Starting relay
The structure diagram of the starting relay is shown in the upper left corner of the figure, which is composed of an electromagnet mechanism and a contact assembly. The coils are respectively connected to the ignition switch terminal and the ground terminal "E" on the shell, the fixed contact is connected to the starter terminal "S", and the movable contact is connected to the battery terminal "BAT" via the contact arm and the bracket. The starter relay is a normally open contact for electric shock. When the coil is energized, the relay core will generate electromagnetic force to close the contact, thereby turning on the attraction coil and the holding coil circuit controlled by the relay.
1. Control circuit
The control circuit includes a starter relay control circuit and a starter electromagnetic switch control circuit.
The starting relay control circuit is controlled by the ignition switch, and the controlled object is the relay coil circuit. When the ignition switch is switched on, the current flows from the battery politics through the starter power terminal to the ammeter, and from the ammeter through the ignition switch, the relay coil returns to the negative electrode of the battery. Therefore, the iron core of the relay produces a strong electromagnetic attraction, and the contact of the relay is closed to turn on the control circuit of the electromagnetic switch of the starter.