Starter system for an internal combustion engine and a solenoid usable in the starter system
First Claim
1. A starter system for an internal combustion engine, particularly for motor vehicles, including:
- a direct-current voltage supply;
an electric starter motor for rotating a movable pinion;
an electromagnetic operating device including a solenoid and an associated movable core which, as a result of the passage of a current through the solenoid, moves from a rest position to an operating position, giving rise to a corresponding movement of the pinion towards an operating position in which the pinion can be coupled for rotation with a rotary member of the internal combustion engine, and to the supply of current to the electric starter motor;
control means for controlling connection of the electromagnetic operating device to the voltage supply and the passage of the current through the solenoid, the control means including a controlled-conduction device connected in series with the solenoid, and a control unit for driving the controlled-conduction device in a predetermined manner; and
sensor means for measuring the current flowing through the solenoid, wherein the current flowing through the solenoid is indicative of any variation of the speed of movement of the movable core and of the pinion;
the control unit being connected to the sensor means and arranged to drive the controlled-conduction device in such a manner that the current flowing through the solenoid causes the speed of said pinion to be below a predetermined value, when the pinion reaches its operating position.
1 Assignment
0 Petitions
Accused Products
Abstract
The system includes a direct-current voltage supply, an electric motor for rotating a movable pinion, and an electromagnetic operating device including a solenoid and an associated movable core. The core moves the pinion towards an operating position in which it can be coupled for rotation with a rotary member of the internal combustion engine. The connection between the electromagnetic operating device and the voltage supply is controlled by an electronic unit which measures the current flowing in the solenoid by means of a portion of the wire forming the solenoid, which portion is bent and preferably twisted, and acts as a resistive shunt.
17 Citations
14 Claims
-
1. A starter system for an internal combustion engine, particularly for motor vehicles, including:
-
a direct-current voltage supply; an electric starter motor for rotating a movable pinion; an electromagnetic operating device including a solenoid and an associated movable core which, as a result of the passage of a current through the solenoid, moves from a rest position to an operating position, giving rise to a corresponding movement of the pinion towards an operating position in which the pinion can be coupled for rotation with a rotary member of the internal combustion engine, and to the supply of current to the electric starter motor; control means for controlling connection of the electromagnetic operating device to the voltage supply and the passage of the current through the solenoid, the control means including a controlled-conduction device connected in series with the solenoid, and a control unit for driving the controlled-conduction device in a predetermined manner; and sensor means for measuring the current flowing through the solenoid, wherein the current flowing through the solenoid is indicative of any variation of the speed of movement of the movable core and of the pinion; the control unit being connected to the sensor means and arranged to drive the controlled-conduction device in such a manner that the current flowing through the solenoid causes the speed of said pinion to be below a predetermined value, when the pinion reaches its operating position. - View Dependent Claims (2, 3, 4, 5, 6)
-
-
7. A starter system for an internal combustion engine, particularly for motor vehicles, including:
-
a direct-current voltage supply; an electric starter motor for rotating a movable pinion; an electromagnetic operating device including a solenoid and an associated movable core which, as a result of the passage of a current through the solenoid, moves from a rest position to an operating position, giving rise to a corresponding movement of the pinion towards an operating position in which the pinion can be coupled for rotation with a rotary member of the internal combustion engine, and to the supply of current to the electric starter motor; control means for controlling connection of the electromagnetic operating device to the voltage supply and the passage of the current through the solenoid, the control means including a controlled-conduction device connected in series with the solenoid, and a control unit for driving the controlled-conduction device in a predetermined manner; and sensor means for measuring the current flowing through the solenoid, the control unit being connected to the sensor means and arranged to drive the controlled-conduction device in such a manner that the current flowing in the solenoid varies according to a predetermined time law, to which a predetermined law of variation of the speeds of movement of the movable core and of the pinion corresponds; wherein the sensor means comprises a portion of the wire forming the solenoid, the portion being bent so as to be substantially U-shaped, and being disposed in such a manner that, in operation, the magnetic flux linkage with the portion is low or essentially zero, and wherein the ends of the portion of the solenoid are connected to the control unit in such a manner that, in operation, the portion of the solenoid acts essentially as a resistive shunt, and the voltage between the ends of the portion is indicative of the intensity of the current flowing through the solenoid. - View Dependent Claims (8, 9, 10)
-
-
11. A solenoid, particularly for use in an electromagnetic operating device usable in a starter system for the internal combustion engines of motor vehicles, comprising an electrical wire wound substantially in a helix, wherein a portion of the wire is bent so as to be substantially U-shaped and is disposed in such a manner that, in operation, the magnetic flux linkage with the portion is low or essentially zero;
- the ends of the portion being accessible to enable the measurement, in use, of the voltage drop in the portion, which is indicative of the intensity of a current flowing in the solenoid.
- View Dependent Claims (12, 13, 14)
Specification