A mechanically driven pump was a necessity in the spreader because electric motorpowered pumps and highly combustible fertilizers don’t mix.
“The best solution seemed to be a drive wheel attached to a pump shaft spun by one of the spreader’s turning tires,” says Tom Jessen, owner of lawn-care equipment maker PermaGreen Supreme. Jessen eventually stumbled on a Companion PO3 pulley from Torque Transmission, Fairport, Ohio, that did the trick.
The pulley has a V-shaped groove on its circumference, which is just the right size to accommodate an O-ring. The O-ring serves as tread on the pulley. An adjustable aluminum hub let Jessen align the pulley with the tire. The glass-reinforced nylon pulley is also lightweight, another criteria for Jessen because he wanted the spreader to be as easy to push as possible.
Torque Transmission custom designed a pulley, complete with O-ring, and PermaGreen Supreme bought 1,500 at $5.74 each. Not only was it a sizable order for Torque Transmission, it saved Jessen the cost of casting pulleys, which would have involved expensive tooling and manufacturing delays.
Inventor Tom Jessen used a pulley from Torque Transmission with an O-ring wrapped around it as the drive wheel for his company’s fertilizer spreader.