Drive Motor 3 2 1 4 8 7 6 5 Drive Motor (1) Shaft. (2) Cover. (3) Thermal switch (thermostat). (4) Commutator. (5) Armature assembly. (6) Field coils. (7) Frame. (8) Brush holder. The drive system is operated by a direct current (DC) motor. Electric storage batteries are the source of power for the DC motor. The four motor brushes are held in four brush hold- ers (8). A spring holds each of the brushes against commutator (4) as the brushes wear. The drive motor is a series wound motor and uses a high temperature insulation. A series wound motor is a commutator motor. The field and armature circuits are a series, which provides a single path for the cur- rent.
Armature (5) is mounted with single row ball bearings at each end. The ball bearings are perma- nently lubricated with a high temperature lubricant. The Optional Superior (S) function equipped lift truckXs drive motor is protected from overheating by a thermal switch (thermostat) (3). The thermal switch opens at 150 L 6ЎC (302 L 11ЎF). It closes at 130 L 7ЎC (266 L 13ЎF). When the normally closed thermal switch is open, the amount of current through the motor is limited to allow the motor to cool. The motor has a fan for cooling. The electrical connections to the motor are made at corrosion resistant terminals on motor frame (7).
On the outside of the motor frame is cover (2) that can be removed for easy access to the brushes and the commutator. Field coils (6) are fastened to the inside of the motor frame. The drive motor is activated when the parking brake is released, the key and seat switch are closed, a direction is selected and the accelerator pedal is depressed. The drive motor powers the power transfer group through shaft (1). Power Train Systems Operation 6