Old Birtman -patent

[DesertTortoise]

http://www.freepatentsonline.com/2280269.pdf

 

[Anachronism]

A hat box Hoover without the brush roll

 

[DesertTortoise]

Look carefully and you can see a brush roll in the diagram.

 

[dysonman1]

That is the patent for an exclusive carpet height adjustment. Notice there are six wheels in a particular configuration. That was an exclusive design for Kenmore and Birtman uprights. Birtman uprights were called Bee Vacs. It worked brilliantly. While the patent shows only five wheels, all production machines that I am aware of used two at the very back.

 

[aeoliandave]

Six Wheel Kenmore

...I saw my first one, other than catalog pix, at the Minneapolis Convention. As usual, its sculptural and engineering beauty entranced me.

Several months later one appeared on Ebay in Bloomington IN and I jumped on it.

The center wheels let the vacuum turn on a dime. It has a swivel handle and a clever

yoke latch that releases the handle from locking upright for storage. One of my 50-ish favorite gems, it's about the be matched and surpassed by a personal Holy Grail upright later this week.

 

[suckolux]

I assume this model has the "bark" on start up that brand seems to have?

 

[DesertTortoise]

I only saw five wheels on the drawings in the patent. I was specifically looking for six btw, but only see five. Tell me if I am missing something.

 

[aeoliandave]

At the time this patent was filed in 1938 most upright vacuums, whether the motor was oriented vertical or horizontal, had 3 wheels, the rearmost often taking the form of a swivel caster.
This patent addresses carpet height adjustment of the brushroll as Tom points out.
A patent is usually for an object in development, not yet finalized. By the time it was granted in 1942 styles had changed, motors were less 'steampunk' in favour of streamline industrial design and the addition of 2 thin wheels in back only added to the stability.
The epitome of this thinking resulted in gorgeous solid polished aluminum motor casings into which the armature was inserted. Kirby carries on this reliable manufacturing method.

 

[DesertTortoise]

Ah, I see. The single rear wheel shown in the patent became two, for a total of six. Very interesting. I kind of thought the patent had to do with the origins of height adjustment.

 

[Gr8DaneDad]

If you read Tom Gasko's reply, he states, and I quote "<a name="start_26487.296733"></a>While the patent shows only five wheels, all production machines that I am aware of used two at the very back. "

 

[ronni]

Good to see "Old Birtie"

 

[DesertTortoise]

Tom, I think he posted while I was typing. I was probably interrupted mid sentence and didn't get back to my post until the good Mr. Gasko has put his post up.