self propelled vacuums.....
Phillip,
Hoover Of course was the first to introduce Self Propelled vacuuming to the world with the Dial-A-Matic in 1967. That continued until 1978, when that line was dropped in favor of the Concept One. Hoover continued Self Propelled of course with the Concept One , Two, PowerMax and etc mostly using the same basic mechanism introduced in 1967. And they are one of the last besides Kirby, and possibly a Eureka or two to still offer that feature with their current WindTunnel line. They never had a trade name for their drive either. Just always called it Self-Propelled.
Kenmore offered the feature for the first time on their Whirlpool built DuoPowers around 1974-75 or so. Their drive was called PowerEase. It was only available on their TOL model. By 1978 or so it was no longer available. It wasn't very reliable, and handles broke and such. Not to mention they made an already HEAVY cleaner, unbearbly so.
Kenmore's second attempt was twofold. Onew was the second generation Whirlpool designed uprights ( think the ones that had the two headlights) that was again a loose copy of the Concept One, and was available in either a soft, or hard bag edition. Whirlpool also sold this machine as well and is comparitively rare. They had no trade name that I know of for thier drive system.
Thier second attempt came from their Singer line of machines. Ryobi Motor Products (nee Singer), popped out a Self Propelled version of their twin fan uprights around 1982 or so. They had a higher hood, and a funky large headlight that was needed to accomodate all the innards to make the thing work. These were only soft bag models IIRC. There were one or two models. One was more deluxe than the other.
Eureka entered the Self Propelled market around 1978 or so. Maybe 1979. Obviously maybe Norm can chime in here as to what year that actually was. I'm clear as a bell that they were the 5000 series machines. They too used the old Continental style metal hood with a plastic dormer on top to accomodate the higher motor to run the gear belt back to the drive post for the PowerDrive unit. They continued the line thru the early 80's, re-spinning it again for the Precision or Procision (sp) line of uprights, also built for Monkey Wards, in several diffeent models. Eureka did not have a name for their drive system either.
And of course Kirby with the Tech-Drive that began in 1993 for the G-3 machines continuing up until today in the current Sentria.
To finally answr your question, the only other "company" to put out a S-P machine that I'm aware of is the half hearted attempt at ressurecting the Singer line during the mid 1980's by Ryobi. There was one or two models in the Singer System lineup that was a clone of the Kenmore version. They made a so-so heavy machine quite chunky, and from what I've seen and heard, were not all that reliable either.
Self Propelled machines I think were passed up by other comapnies, or brand names becasue they were "truly limited" in their honest usefulness. Not only did other "brands" not have the nescesary Research and Development abilities to create such a thing ( and really besides the ones mentioned, how many more brands really were there at the time). They made a machine much more heavy and bulky, were usually jerky in operation and they diddn't work all that swell in thicker carpets which were all the rage when these things were out on the market.
And finally they made the machine cost WAY more than a non- powered companion line model. Both to produce and to sell.... Bad news bears for a compnay that really needed volume to survive.
Really only Hoovers Self Propelled system was really any good IMHO, with Eureka's a close second. And the reason why Hoover and Kirby still do theirs is becasue they push them really hard in the marketplace. In most cases where self propelled machines truly failed anyway in one for m or another....
Hope this helps...
Chad
Ann Arbor Michigan
Oh yeah BTW, there WAS one other that I just remembered. Panasonic, used to have a PowerHead on their TOL canisters around 1992??? area, which used a reversible motor, thru a quite complex linkage and electric switch arrangement that caused the motor to first propell forward when pushed forward, and when tugged backwards, the brush pushed backwards. Because their brushroller was quite agressive, it really did "propell" the nozzle as it intended.
However what did that head in was it's finiky switch and linkage setup which broke FREQUENTLY, and out of adjustment never allowed the head to properly clean correctly....
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