Motion control system for materials handling vehicle

An automatic coast control device for a hand/rider truck provided with a brake comprising a deadman brake mechanism, a steering mechanism comprising a steering arm having an upper and a lower end, said steering arm being movable to a position causing engagement of said brake, an electrical power circuit comprising a high speed control circuit and a low speed control circuit, said control circuits controlling, respectively, a high speed travel mode and a low speed travel mode of said truck, and means for selecting said high speed or said low speed travel mode, said device comprising:

• a movable housing sleeve closed at one end by a wall provided with a coast arm pivotally connected to the lower end of said steering arm;
• a movable slide disposed within said housing sleeve;
• a spring capable of compression disposed and constrained between said housing sleeve and said slide;
• a stem movably mounted within said slide and provided at one end with engagement means for engaging said slide;
• and
• actuator/deactuator means connected to said engagement means for actuating said engagement means when said low speed travel mode is selected and said low speed control circuit is thereby energized and for deactuating said engagement means when said high speed travel mode is selected and said high speed control circuit is thereby energized;
• whereby, generation of an electrical signal within said low speed control circuit actuates said actuator means, causing said engagement means to engage said slide, thereby producing compression of said spring, said compression urging said steering arm away from said position causing engagement of said brake, thereby automatically overriding said deadman brake mechanism while said truck is in said low speed travel mode.