RU2244153C2 - Circuit to cut in starter of internal combustion engine - Google Patents

Abstract

FIELD: electrical engineering.

SUBSTANCE: invention relates to internal combustion engines, particularly, to cut-in circuit of engine starter. According to invention, proposed circuit contains storage battery, starter switch, dc motor and solenoid switch with power contacts and hold-on and pull-in windings. Output of pull-in winding is connected with frame through additional normally-closed contacts. Limiting resistor is connected in parallel to said contacts.

EFFECT: increased magnetizing force and holding effort without increasing overall dimensions and mass of solenoid switch.

1 dwg

Description

The invention relates to electrical engineering, in particular to a starter circuit for an internal combustion engine.

There is a known scheme for turning on the starter of an internal combustion engine (ICE) (Theory, design and calculation of automotive electrical equipment, under the editorship of MN Fesenko. - M .: Mashinostroenie, 1979, p.65) containing a storage battery, a starter switch, a constant motor current and relay having a retracting, holding windings and power contacts. The relay solenoid coil is connected in series with the starter motor, and the holding coil is in parallel, the relay power contacts are connected between the battery plus and the electric motor. The starter switch is connected between the battery plus and the common output of the relay windings. After turning on the starter relay, its power contacts close, and the voltage is supplied to the electric motor. Both terminals of the retractor winding are connected to the positive terminal of the battery.

A disadvantage of the known circuit is the occurrence of reverse current in the retractor coil of the relay after closing its power contacts. This is due to the fact that the resistance of the power supply circuit of the relay windings through the starter switch is greater than the resistance of the power supply circuit of the electric motor through the power contacts of the relay and the voltage drop in these sections is different. The increased resistance of the power supply circuit of the relay windings is due to the fact that this circuit is made of a wire with a small cross section and contains a significant number of plug connections (for example, on VAZ cars, this circuit has a resistance of 0.15 Ohms). The power supply circuit of the electric motor through the power contacts of the relay is made of a large copper wire with a minimum number of bolted contact joints and has a total resistance of the order of 0.005 Ohms.

In this regard, at the terminals of the retracting winding there is a potential difference, under the action of which a reverse current flows in it. This current reduces the magnetic flux generated by the holding winding, and reduces the force of the electromagnet in the on position in the holding mode.

As a prototype of the proposed circuit, the well-known starter switching circuit is used (Japan No. 54-38703, class MKI F 02 N 11/08), in which the output of the retracting winding is connected to the ground through additional normally closed contacts that turn off the retracting winding after the relay is activated for eliminating the occurrence of reverse current in it.

The disadvantage of the prototype is that in the known scheme in the holding mode, the retracting winding is turned off and the magnetizing force is created by only one holding winding. This leads to a decrease in the magnetizing force of the coil containing two windings and to a decrease in the developed holding force starter relay.

The objective of the invention is to create a starter switching circuit, which allows to obtain an increased magnitude of the magnetizing force and holding force without increasing the dimensions and mass of the relay.

The problem is solved in that in the connection circuit of the starter of the internal combustion engine in parallel with additional normally closed relay contacts, a limiting resistor is included.

The drawing shows a diagram of the starter.

The starter circuit of an internal combustion engine includes a battery 1, a starter switch 2, a DC motor 3, a traction relay having a retractor 4, holding 5 windings and power contacts 6. The resistance of the retracting winding 4 is several times less than the resistance of the holding winding 5. Power contacts 6 of the relay are connected between the plus of the battery 1 and the electric motor 3. The output of the retractor winding 4 is connected to the ground through additional normally closed contacts 7. In parallel with the additional contacts 7, a limiting resistor 8 is connected.

When the contacts of the starter switch 2 are closed, the voltage is applied to the common terminal of the solenoid 4 and holding 5 relay windings. Under the action of the magnetic flux windings created by the current, the relay armature is retracted, closing the power contacts 6, and voltage is applied to the output of the electric motor 3. When the relay is activated, the additional contacts 7 open and the current of the retractor winding 4 is shorted to ground through the limit resistor 8. Due to the fact that the limit resistor 8 reduces the current of the retractor winding 4 to the level of the retention winding 5, the retractor winding 4 does not overheat during prolonged operation in the holding mode. The current flowing through the retracting winding 4 in the holding mode creates an additional magnetizing force that increases the force of the electromagnet.

Claims (1)

A starter circuit for an internal combustion engine, comprising a battery, a starter switch, a DC motor and a traction relay having power contacts and holding and retracting windings, the terminal of the latter being connected to the ground via additional normally closed contacts, characterized in that it is parallel to an additional normally closed The pins have a terminating resistor.