Interlock control system for power machine

An apparatus for controlling operation of a skid steer loader having a seat, wheels, a drive mechanism for driving the wheels, a lift arm structure manipulated by hydraulic actuators, and a hydraulic circuit for controlling the hydraulic actuators, the apparatus comprising:

• occupancy sensor means, coupled to the skid steer loader, for providing an occupancy signal indicative of occupancy in the seat;
• traction lock override means for providing a traction lock override signal;
• controller means, coupled to the traction lock override means and the occupancy sensor means, for providing a traction output signal and a hydraulic output signal based on the traction lock override signal and the occupancy signal;
• traction lockout means, coupled to the drive mechanism and the controller means, for locking the drive mechanism to preclude the drive mechanism from driving the wheels based on the traction output signal;
• and
• hydraulic lockout means, coupled to the hydraulic circuit and the controller means, for locking out operation of the hydraulic actuators based on the hydraulic output signal.

An apparatus for controlling operation of a skid steer loader having a frame, a seat supported by the frame, wheels supporting the frame, a drive mechanism for driving the wheels, a lift arm structure manipulated by power actuators, and a power circuit for controlling the power actuators, the apparatus comprising:

• an ignition switch;
• a seat bar coupled for movement relative to the seat;
• a seat bar sensor, coupled to the seat bar for sensing position of the seat bar and providing a seat bar sensor signal indicative of the position of the seat bar;
• a seat sensor, coupled to the seat, for sensing whether the seat is occupied and providing an occupancy signal indicative of occupancy in the seat;
• traction lock override means for providing a traction lock override signal;
• controller means, coupled to the traction lock override means, the seat bar sensor, the ignition switch, and the seat sensor, for providing output signals including a traction output signal, a power output signal, and a display output signal, based on the traction lock override signal, the seat bar sensor signal, the occupancy signal, and the input from the ignition switch;
• traction lockout means, coupled to the drive mechanism and the controller means, for locking the drive mechanism to preclude the drive mechanism from driving the wheels based on the traction output signal;
• power lockout means, coupled to the power circuit and the controller means, for locking out operation of the power actuators based on the power output signal;
• and
• display means, coupled to the controller means, for displaying indicia indicative of an operational state based on the display output signal.