In 1979, S.I. Fishgal made his rock crusher inventions for, but did not assign to Joy Manufacturing Co. (Pittsburgh, PA). The crushers were transmission, fluid-driven and impact ones as follows:
Double-Acting Single and Dual Eccentric, Cam Cone and Jaw, Arcuated-Jaw, Twin-Jaw, Coil Cone, Toothed Gyratory, Horizontally Fed Single and Dual Swing Jaw, Roll Jaw, Multi-Roll, Multi-Eccentric Jaw, Eccentric Twin-Jaws, Hydraulic Cone, Gyratory and Jaw, Fluid-Actuated Gyratory and Jaw, Expansionary Actuators, Blasting Jaw, Combustion, Electric Steam