Making "Fishing" Work
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The automata action is created by a mechanism that uses cams, geneva mechanisms, gears, counterweights, levers, and a swing hammer. The gear reduction from the handle to the main shaft is 9.6 to 1. Power transmission is through hand-cut 3/8" thick gears. The video to left is a guided tour.
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There are two separate geneva mechanisms to provide intermittent action to the piece. One controls the largemouth bass that lunges out from under the dock and the other lifts a hammer weight that causes a little fish to jump when Billy raises his line. Each action occurs at different times on every fourth rotation of the main shaft, or every 38.4 rotations of the handle.
Cam followers on this piece all have wheels to reduce the friction since there is a re number of loads in this piece. The two cams that activate the catfish and crayfish run off the secondary shaft and operate at twice the speed of the main shaft.
Counter weights are used in some cases to reduce load by balancing or to provide mass for gravitational forces to return a component to a neutral position. (For example hidden in Billy's body are counterweights to balance the weight of his outstretched arm.)
Two of the more subtle movements in the piece are that when the largemouth bass is fully extended his mouth closes and his eyes roll back in his head.
Cam followers on this piece all have wheels to reduce the friction since there is a re number of loads in this piece. The two cams that activate the catfish and crayfish run off the secondary shaft and operate at twice the speed of the main shaft.
Counter weights are used in some cases to reduce load by balancing or to provide mass for gravitational forces to return a component to a neutral position. (For example hidden in Billy's body are counterweights to balance the weight of his outstretched arm.)
Two of the more subtle movements in the piece are that when the largemouth bass is fully extended his mouth closes and his eyes roll back in his head.