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In the Piston Side photo, you will see the epicyclic gearing that is used for deriving the straight line motion. A requirement for straight line motion is that the pivot be on the pitch circles of the two gears. In earlier versions (this was invented in the 1800's!), a tab was applied to the inner gear to carry the pivot. Richard solved the problem of the tab by making one tooth on the planet gear twice size, and the corresponding tooth spaces in the ring gear to correspond. Photo 5 is a close-up view of the gears.
The valve motion is regulated by a peripheral cam, as shown in the "Cam Side" photo. These two features, we believe, make Straight Arrow a unique engine. Design is by Richard Egge, who made the gears and cam.
Richard is an instructor in Machine Tool Technology at DeKalb Tech in Clarkston, Georgia, a suburb of Atlanta. Students in the Machine Tool program are in a two year program yielding a diploma in MTT, and become machinists or CNC Programmers (often before graduation!). DeKalb Tech is a two-year unit of the University System of Georgia.
Technical notes: The epicyclic gear system is a straight line motion invented in the 19th century, but in this case fabricated with modern technology: a wire EDM machine, controlled by a computer program. The original cam was made in two pieces on a CNC milling machine and later modified by using the CNC rotary table to cut the peripheral slot. The cam follower and linkage was made by Roy Rice, using conventional machining methods. The piston and valve are graphite turnings, and the lamp is a dummy doorknob.
Straight Arrow has turned out to be one of the easiest starting Flame Lickers that I have experienced. The only problems have been slow starting from the cold state, caused by condensation from the alcohol burner. After a short warm-up, a single flip of the flywheel (cam) will start the engine, and it runs merrily for many minutes without trouble. We attended the 1998 NAMES exhibition, where we showed our engines, and where Straight Arrow performed flawlessly.