Johnson Crushers International

Kwikee Products Co., Inc.

Benjamin James Boyce

James R Kunz

Lawrence C Olsen

Malcolm M Maccabee

A vibrating screen assembly supported by springs is provided which is used to size separate rock and other material. The present invention includes increasing the natural frequency of the screen assembly by stiffening the individual screen decks of the screen assembly, to enable the screen assembly to operate at higher operating speeds without prematurely failing.

Vibrating screen

The step assembly (,) includes a housing (,) which is mountable to a recreational vehicle, typically underneath the door of the vehicle. A pair of linkage arms (,) and (,) are rotatably coupled at their lower ends to each side of the housing (,). The step assembly (,) contains an upper tread assembly (,), a center tread assembly (,), and a lower tread assembly (,), respectively including an upper step (,), a center step (,), and a lower step (,). The upper ends of the linkage arms (,) and (,) are rotatably connected to the upper portion of the upper tread assembly (,). The center tread assembly (,) is slidably engaged with the upper tread assembly (,) through a slideway assembly (,). The lower tread assembly (,) has a lower tread pivot arm (,) which is rotatably coupled to the center tread assembly (,) by a pin (,) mounted on the center tread assembly. The lower step (,) has a lower face (,) that substantially closes off the housing (,) when the step assembly is in a fully retracted position, forming a continuation of the vehicle outer surface. A linear actuator (,) is connected to the housing (,) and one of the tread assemblies, in order to extend and retract the tread assembly relative to the housing (,).

Growing community of inventors

Eugene, OR, United States of America

Benjamin James Boyce