Patent Page

Rockford Speed Governing

| November 2005


Gas Engine Patents of Note

In a perfect world, everything is built, well, perfectly. But alas, we don't live in a perfect world, so we must build to the best of our abilities, taking the advice and using the principles of others who came before us.

This patent, a "Governor for Explosive Engines," shows how not to build a governor. Although probably an effective design, it is overly complicated and uses far too many moving parts. Nevertheless, it would be very interesting to watch one of these Rockford engines run.

Its inventor, Frederick C. Zumdahl of Rockford, Ill., assignor to Rockford Engine Works, stated: "The object of this invention is to provide novel and effective means for automatically governing the speed of explosive engines."

How it Works

When the crankshaft (2) rotates, a spur gear on the end of the crank (14) meshes with another spur gear (15). This second spur gear (15) has a cam (17) attached to it. The cam makes contact with a roller (20) on the upper end (19) of the rocker arm (not numbered) mounted to the engine frame on a stud (18). The lower end of the arm (21) has a block (22) with a notch in it (23). One end of the bell-crank (24) holds an ad-justable detent (25). The beveled end (29) of the detent fits securely into the notch on the lower arm.

The other side of the bell-crank (30) has another arm attached (31). This arm has a shoe (32) on one end and a threaded rod (33) with nut (34) on the other. The rod is surrounded by a coil spring (36); another coil spring can be found between the nut (34) and bell-crank arm (24).