User:Veeder Root Doc/sandbox

YOCOM: CRANKBACK VEEDER ROOT COMPUTER 1932-1949 The first Mechanical Computer for computing the dispensing of gasoline was introduced into service in the Wayne #40 pump in 1932. Terminology for this unit was "Crankback" This unit was manufactured by the Veeder Root company, and became the standard for the industry. Newer models of mechanical Computer are still used today using the same basic design to calculate price.

The Computer is driven by a fluid measuring device called a Meter. The Computer displays price per gallon, amount of gallons delivered and amount of sale. The first Computers only computed price up to 49.9/10 and had no wheels to display price. In 1935, wheels to display price were incorporated into the design. The top part with the numbered wheels is called the Head, the bottom part is called a Variator. It is the Variator that through 3 adjustable range arms, 10 cent range, one cent range and 10ths cent range, and a conical graduated gear on the center input shaft calculates the price of gallons delivered.

All three range gear assemblies are driven from a center conical graduated gear (that is attached to the center shaft) and converge into a planetary gear "cluster" (above the conical gear) that is on the same center shaft yet can turn independantly. That in turn, sets the ratio of the singular output gear on top of the cluster that drives the Money wheels in the Head. The gallons wheels in the Head are driven from a gear on top of the center input shaft, thus making the calculations for gallons come directly from the Meter below.

The Head does not calculate and is but is a means to numericly display calculations (price of purchase) and gallons (delivered) amounts the variator conveys to the Head. The Head is also used to reset the numbers back to zero, before the next delivery. 4 revolutions of the input shaft from the Meter into the Variator will register 1 gallon in the Head. Display of money wheels in the Head depend on what price the range arms in the Variator are set at. Setting the range arms in different price locations changes the ratio output to the Head.

There is a sub unit with 2 sets of 1" Dia. numbered wheels that keep up with the total amount of sale on one set and total amount of gallons on another set, this Part is called the Totalizer. The Totalizer would be read at the beginning and the end of each day so to keep up with sales.

Computer type Gasoline Pumps had a L shaped handle on the side that is still called a "Crankhandle","Crank" for short, the Computer had to be reset "Set Back" to zero by turning the Crankhandle or Crank, 1 full 360 degree cycle. This is where the term Crankback Computer came from.

Sources;,, Patent number: 2264557,, Patent number: 2213597,, Illustrated Guide to Gas Pumps #2 Jack Sim Author,, 24 yrs experience restoring crankback computers. 29 yrs rebuilding gasoline pump components