General Information
DRIVE MOTOR
When the water level/pressure switch is satisfied circuits are completed to the main drive motor. The drive motor is a special high torque
Contact sets in a timer or in a motor reversing relay provide proper connection to the motor to cause it to run clockwise in agitate and counterclockwise in spin (viewed from the top).
The motor drives the power unit by means of a special design “V” belt. The belt has a “slip factor” designed to act as a slip clutch.
TRANSMISSION
The helical drive shaft drives a pinion gear (which is splined to the top of the drive shaft) at approximately 618 r.p.m. This drives the bevel gear at approximately 150 r.p.m.
The pivot pin of the yoke portion of the torque block and yoke assembly is driven in a circular motion (orbit) around an imaginary center point of the bevel gear center axis. The yoke drives the torque block back and forth through an arc of approximately 97 degrees at the rate of about 150 times per minute. Because this is a continuous motion, the drive provides very smooth operation. The low number of parts results in improved dependability. This gear case can be serviced without removing it from the washer.
HELICAL DRIVE
The helical drive mechanism used in the washer is simple
-not requiring a special device or linkage to shift the washer from agitation to spin.
The drive mechanism utilizes a reversible motor and helical (threaded) drive shaft. A pulley which is threaded to the helical drive shaft moves either up or down the shaft dependent upon the direction it is turned by the drive motor by means of a drive belt.
AGITATION
When the pulley is turning counterclockwise (viewed from the bottom) it moves down the helical drive shaft. As it
rotates down the shaft, a lug on the pulley comes against a drive lug which is splined to the helical drive shaft. At this point the drive shaft turns with the pulley. The pulley bearing which merely resting on top of the pulley also rotates with the pulley, drive lug and helical drive shaft.
At the top of the drive shaft is a spined gear. As it rotates it drives a series of gears causing the agitator to move back and forth in an arc creating the water action for the wash.
The tub and transmission are locked in place and cannot turn because the brake rotor and brake shoe (which is splined to the transmission ) is being held down against the brake drum by the brake spring.
SPIN
When the motor reverses, the pulley will turn in a clockwise (viewed from the bottom). This causes the pulley and bearing to turn. The pulley climbs the threads on the helical drive shaft overcoming the force of the brake spring to lift the brake rotor and brake shoe off the brake drum.
As the pulley climbs the shaft and overcomes the force of the brake spring, there is a downward pull on the shaft.
Within the transmission there are two washers which act as a spin clutch. This is a friction clutch consisting of a bronze washer which is splined to and turns the drive shaft. Between this washer and the pinion gear is a steel washer which is locked to the transmission case.
As the helical shaft is pulled downward, the two clutch washers under the pinion are forced together. This is done rapidly and slippage occurs only during the first two or three revolutions, until the film of oil between the two clutch washers is forced out.
The drive occurs when the washers are forced together and the pulley has climbed the shaft as far as it can. The driving force has locked the pulley, brake rotor, drive tube and gear case together and all will turn as a unit in the same direction as the pulley is turning, causing the tube to spin is a counterclockwise direction (as viewed from the top).
Spin cycle completed:
When the washer reaches the end of the spin cycle, the drive force is removed. Thus, there is no force supplied to lock the components together or to compress the brake spring. Therefore, the downward force of the brake spring and the momentum of the spinning washbasket effectively reverse all the actions outlined above.
©2003 Maytag Appliances Company | 16022842 Rev. 0 | 9 |