Figure 5-25. - Fuel pressure switch.
terminates whenever the water level sensing switch closes. When the water level sensing switch is finally activated, the timer starts running and the agitation operation commences.
The AGITATION operation function is to provide washing and rinsing of the laundry once the tub is filled with water. There are two basic methods of washing action in general use. One is a reciprocating agitator tank. The other is a rotating drum that picks up the that swirls the water and clothes back and forth in a clothes and allows them to drop into a pool or stream of water. Most automatic washers are of the agitator, top-loading variety.
The SPIN operation function is to remove excess water from the laundry fabrics. During this operation, the main drive motor spins the laundry tub at a relatively high rate of speed, forcing water out of the tub and laundry fabrics by means of centrifugal force. The drain pump removes this spun-out water from the washer; therefore, the DRAIN operation function is to pump the used wash water and rinse water out of the washer and into the wastewater system.
Modern automatic clothes washers include a number of optional features that do not appear as necessary parts of the timing diagram. The more common options are as follows:
Most washers have a high/low water level selector switch; some give the user a choice of high, medium, and low water levels; and a few washers have an "infinite" water level adjustment that lets the user set the water to any desired level. The purpose of such a switch is to conserve water whenever the laundry tub is only partially filled with laundry. Some washers do not have a water level selector switch, and all wash and rinse phases run with the tub filled to capacity.
In most washers you normally have access to a set of switches, push buttons, or a dial that allows a choice of water temperatures. Newer and better washers have separate selector switches for the wash water and rinse water phases; hot water, warm water, or cold water for the washing phase; and warm water or cold water for the rinsing phase. In the simplest washers, the switch might only permit a selection of either hot or cold water for both the washing and rinsing phases of the wash cycle.
The agitation speed selector lets you select a normal or gentle speed for the agitation action. The gentle speed is used only in instances where there is a chance that normal speed might harm certain types of fabrics. It is important to note that this speed selector switch does not influence the timing in any way. For example, if you set up a 10-minute washing operation, the operation occupies a full 10 minutes whether the agitator speed is set to normal or gentle.
An automatic washer can be an elaborate piece of electromechanical equipment. Most modern washers have a number of basic electrical and mechanical parts that work much the same way in every make and model. The primary parts include the following:
1. a timer assembly,
2. solenoids for controlling the inflow of hot and cold water,
3. a transmission and a main drive motor for providing the powerful agitation and spin actions, 5-25Continue Reading