US 4,392,544 A · Controller for electric traction motor

Abstract

A controller (10) for the traction motor of an industrial truck comprises an actuator spool (56) which is axially shiftable by a manual selector member (12) for actuating a plurality of control switches (44,46,48). Detent means (86,78,82,84) hold the spool in forward, reverse or park positions and a return spring (66) urges the spool toward neutral position. The actuator spool (56) is adapted for rotational movement about its axis for automatic release of the detent means and return of the spool to neutral position. A seat occupancy detector (18) is actuated when the driver leaves the seat and imparts rotational movement to the spool which releases the detent means and returns the spool to neutral. The controller is also adapted to provide manual and automatic control of a parking brake (6). When the selector member is in the park position, cam means (184) on the actuator spool actuates a control switch (48) to apply the vehicle brake. When the selector member is in the forward, reverse or neutral position the control switch is operative to release the brake with the driver on the seat; if the driver leaves the seat the spool is rotated and actuates the control switch for applying the parking brake.

Claims8

Dependent claims

A controller for use in a vehicle having an electric traction motor with forward and reverse drive means,

a controller housing,
control means adapted to be actuated for selecting forward and reverse drive,
an actuator spool mounted in said housing and adapted for axial movement to neutral, forward and reverse positions,
cam means on said spool for selectively actuating said control means,
a manually actuable selector member movable to neutral, forward or reverse positions and being operatively coupled with said actuator spool for axial movement thereof to corresponding positions for selective actuation of the control means by said cam means,
detent means coacting between said spool and said housing for holding said spool in said forward or reverse position,
bias means continuously urging said spool toward said neutral position,
release means for releasing said detent means whereby said spool and said selector member are returned to said neutral position by said bias means,
and condition responsive means for actuating said release means.

6 more elements

Dependencies are inferred from the claim text.

Controller for electric traction motor

Life of this patent

Controller for electric traction motor

Life of this patent

Abstract

Claims8