jackshaft


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jackshaft

[′jak‚shaft]
(mechanical engineering)
A countershaft, especially when used as an auxiliary shaft between two other shafts.
References in periodicals archive ?
After a long day of moving the pieces around to optimize the relative positions of the engine, jackshaft, gin and condenser, everything was bolted to the floor.
A homemade device cobbled together with disparate parts, it uses the frame of a Model T auto, wheels from a Ford Falcon (adapted to make the rims fit), front and rear Model I axles (cut and narrowed), a jackshaft to reduce the speed of the 1935 Plymouth transmission, a Rockford twin-disc clutch off a 4-cylinder Wisconsin engine, a Model T steering wheel and emergency cable handbrake, and a Little Giant steam boiler (serial no.
Where a belt formerly connected the pedals and the rear wheels to make the foot-powered pedal tractor go, Ron added a jackshaft with two sprockets (one small, one large) to get the gears to turn slower under power from the weed whip.
In the case of the engine, Denny removed a little jackshaft, then a couple of U-joints and the drive shaft.
The 1-inch jackshaft is mounted on a slide to give the short belt the correct tension.
I installed a jackshaft between the engine and flywheel, which helps to get gear ratio satisfactory.
This shaft was connected directly to the blade on some models, while another model called the Flying Cloud used a V-belt from this shaft to another jackshaft that drove the blade.
This configuration requires sheaves, belts and jackshafts to lower the speed to 600 to 700 RPM, which is ideal for a 60-inch or 80-inch mill.
Overall system friction was reduced when unnecessary gearing, jackshafts, cams, couplings, etc.