HEATER GP-CAB 1525087 - Caterpillar

When the axle is shifted to LOW range, sliding clutch (12) engages planetary pinions (11) and bearing adjustment nut (13). The idler pinion gears rotate between bevel gear (9) and the sliding clutch gear while the center points of the idler pinion gears rotate at a speed less than the ring gear speed. The pinion shafts drive the differential assembly at this slower speed.When the axle is shifted to HIGH range, sliding clutch (12) is meshed with the teeth of clutch plate (10) and planetary pinions (11). This causes the planetary pinions to rotate with bevel gear (9) instead of rotating about the center points of the pinions. Since the planetary pinions are rotating with the bevel gear, the pinions rotate the differential case at ring gear speed. The rotation of the differential case rotates the spider, the differential pinions, the side gear, and the axle shafts about the shaft centers at the RPM of the ring gear.Note: The axle is shown in the HIGH speed range.Rotor Axle Shift Circuit
Illustration 3 g00764555
(1) High range switch (2) Electric motor (3) Circuit board (4) Low range switch (5) Slider block gear (6) Case (7) Springs (8) ResistorThe rotor axle shift circuit consists of the speed range switch and the rotor axle shift unit. The speed range switch is a two-position toggle switch that is mounted in the console. The shift unit is mounted on the rotor axle.Electric motor (2) is electrically connected to high range switch (1) and low range switch (4). The electric motor has a worm gear that is mounted on the motor shaft. The worm gear meshes with slider block gear (5). The slider block gear has a depression that is molded into the gear upper surface and a hole for a pin on the lower surface. The pin rests in a slot in the slider block assembly. As the slider block gear rotates, the pin slides the slider block case (6) in one direction or the other direction. This compresses one of the slider block springs (7). Circuit board (3) that contains resistor (8) that is included in the unit. The resistor is also electrically connected to the high/low range switches. The slider block assembly consists of two springs (7) that are mounted inside case (6) .Electrical System for the Shift Control
Illustration 4 g00764558
Shifting in High Range (STARTING) (1) High range switch (4) Low range switch (5) Slider block gear (9) Cam pin for low range (10) Gear ramp (11) Cam pin for high rangeWhen the transmission is in LOW, the circuit between axle speed range switch (1) and shift unit low range switch (4) is completed. The circuit between the speed range switch and high range switch (1) is broken.Cam pin (9) for the low range switch rests in gear ramp (10). This opens the circuit between the switch and the motor and this closes the circuit between the switch and the resistor in the circuit board.Cam pin (11) for the high range switch rests on gear