SUPPORT, COOLER EGR 7095091C1 - Caterpillar

Toggle Switch Steering System
Illustration 1 g00662971
Diagram of the Steering System (1) Toggle switch steering (2) Terrain toggle switch steering (3) Activation switch (toggle switch steering) (4) Seat direction switch (5) Steering cylinders (6) IQAN (7) Implement control valve (A) Line to the steering metering pump (B) Line to the steering metering pumpThe toggle switch steering system is activated by activation switch (3). When activation switch (3) is in the OFF position only the steering wheel can be used to articulate the machine.Either of the two toggle switches can be used to control the speed of turning. As the toggle switch is moved further from the CENTER position the machine will turn faster. As the toggle switch moves further from the CENTER position, the resistance in the circuit changes. This changes the voltage that is sent to the IQAN. At the LEFT position, the voltage is approximately 0.5 Volts. At the RIGHT position, the voltage is approximately 4.5 Volts. At the CENTER position, the voltage is approximately 2.5 Volts.The magnitude of the voltage from the toggle switch controls the current from the IQAN to the proportional solenoids in implement control valve (7). Two solenoids in the implement control valve control the steering. One solenoid controls the oil flow for left turns. The other solenoid controls the oil flow for right turns.The magnitude of the current to the proportional solenoids controls the amount of movement of the solenoids. The movement of the solenoids controls the flow of oil to the steering cylinders. More oil flow to the cylinders will increase the speed of steering.When the operator rotates the seat, seat direction switch (4) is switched. The IQAN then sends current to the other proportional solenoid. This enables the operation of toggle switch (1) to function in the same manner in the forward direction or the reverse direction.