Abstract: A safety device for a self-propelled machine with a steering rod guided by an operator's handle includes a safety handle positioned proximately below the operator's handle in parallel to at least a portion of the operator's handle for grasping by the operator. The safety handle has first and second arms projecting vertically downward. A shaft is rotatably mounted in the steering rod below the safety handle, and a sleeve is journalled on the shaft. The first and second arms of the safety handle are rigidly attached to opposite ends of the shaft. An operating disc for controlling the motion of the machine is rotatably mounted in the steering rod. A spring normally biases the operating disc to maintain the machine in a stationary position. A locking arm is rigidly attached to the sleeve and engages teeth in the operating disc for securing the operating disc in a fixed position whereby the motion of the machine is constant.

Abstract: A vibrating tamper with side-by-side engine section and tamper section connected by a suspension system including leaf springs. The tamper section includes a reciprocating leg terminating in a tamping plate. The engine section includes handles, an engine with a rotary drive shaft, and a transmission for converting the drive shaft rotary motion to reciprocating motion to be imparted to the tamper. A driven, eccentrically mounted roller cooperates with a lever forked at one end to embrace the roller. At its other end, the lever applies reciprocating drive to the tamper. The reciprocating drive is applied through helical springs encircling the tamper leg. The forked lever end and eccentric assure that forces substantially parallel the axis of the tamper leg are transmitted to the tamper section, minimizing forces perpendicular the leg.