Nilfisk-Advance Nilisk-Alto 866 Service Manual

Service Manual: Clarke Focus II Midsize, Nilisk-Alto ScrubTec 8Form Number 5043117 Page 57SCRUB SYSTEM, DISCFUNCTIONAL DESCRIPTIONThe disc scrub system moves the scrub head up and down and turns the scrub motors on at of at the operator’s requestto provide loor scrubbing acion. The discs spin toward the center at the front edge of each disc. The head is moved upand down by an electric actuator motor that has integrated posiion switches. The weight of the scrub head providesthe downward pressure in the normal scrub mode. When extra pressure is requested the actuator moves down farthercausing a gas spring to exert addiional downward pressure on the loor.The main machine controller energizes the brush solenoid to turn on the brush motors when the following inputs havebeen met:• Key switch on• Operator request – One Touch Control Buton pressed• Machine moving signal is received from PG Drive Motor Controllero Approximately 17 volts received from the main controller (J1 Pin 4) is switched to batery negaive by theDrive Motor Controller, dropping the voltage to 0 volts.The main machine controller directly drives the brush head actuator. It applies system voltage across the two actuatormotor wires to move the motor up. It reverses polarity to move the motor down. The brush head actuator also has 3posiion switches built into it to let the main machine controller know how high or low the brush head is. Each switchreceives a 5 volt feed through a resistor from the controller which returns back to batery negaive on a common wireto connector J3 pin 7. The controller has “internal voltmeters” which monitors the signal voltage of each switch circuit.When the switch is closed, the voltage signal is nearly 0 volts. When the switch is open, the voltage is approximately 5volts.• Full Up Posiion = M0 is 5v (M1 and M2 are both 0v)• Normal Scrub Posiion = M1 is 5v (M0 and M2 are both 0v)• Extra Scrub Pressure Posiion = M2 is 5v (M0 and M1 are both 0v)When the key is turned on the main machine controller looks to see if the brush head is fully up by monitoring the M0switch voltage. If it is not 5v, it drives the actuator to the full up posiion. When the operator presses the One TouchControl Buton the controller drives the actuator down unil it sees the M1 switch open (5v). If the operator pushes theIncrease Brush Pressure Buton, the controller drives the actuator further down unil it sees the M2 switch open (5v).When the operator pushes the One Touch Control Buton again to turn the scrub funcion of, the controller drives theactuator motor up unil it sees the M0 switch open again (5v).