Huh, I wonder if it had a DC motor...
Unfortunately, one of the few Frigidaire washer manuals I am missing is the 1967 Tech Talk Supplement (Vol 67, No. 11) that covers the late release L series WXL washer. The WXL was released for sale much later in the 1967 model year, requiring a separate parts sheet and Tech Talk article to be published for the new variable speed washer. It should also be noted that the N series washer service manual also covers the variable speed clutch.
GM made a total of 4 varriable speed machines from 1967 till the release of the 1-18 washers in 1970: WXL (1967), WXN (1968), WCDXN (1968), WXP (1969 model year). These were TOL/Custom Imperial machines with the exception of the WCDXN Custom Deluxe. I guess the marketing folks figured that if they had an optional rapid-dry CD machine, they may as well stretch the cost across as many models as possible.
Years ago I stumbled upon the late 68/early 69 Tech Talk supplement for the WXP, WCDXN, and WXN washers. Fascinating what GM attempted with a magnetic clutch, a few transistors, and a low voltage transformer. The washer does indeed utilize the familiar 120v motor found in other Roller-matics.
While the supplement below does not cover how the clutch works, a service tip is described, indicating that if you remove the control module circuit between the control coil and apply straight 12v to the control coil from an external source, the machine should spin/agitate at full speed. It appears the motor shaft slides through the center shaft of the clutch assembly, and attaches to the clutch driver plate. The clutching action happens between the lining and the driven plate. The driven plate has notches evenly spaced on the parameter of the pate, providing an on/off signal to the speed sensor. I'm not electronics/electronic clutch expert, but I suspect the control module reads this signal and appropriately adjusts a pulse to the clutch coil until the preset resistance is similar between the speed control from the control panel and the speed sensor. That still doesn't account as to why full 12v at the sensor would provide full speed unless a fully charged coil allows the clutch to spin freely and a varied voltage would cause the magnet to drag the clutch for lower speeds. LOL, now I'm thinking out-loud!
Mag clutch experts - please correct me as I'm much more versed in standard mechanical clutches.
I've included a few scans below. If Robert would like I did scan the whooping 16 page manual in case there is interest to have it posted in the service manual section of the site.
I'd love to find and tear into a WXL or WXN someday, or see one in person. [this post was last edited: 12/2/2010-22:01]
