Abstract: A hoist drum control includes a drum clutch control pressure graduating valve (15) connected between a pressure air source (14) and a shuttle valve (21), the latter being connected in a line to the drum drive clutch cylinder (25). Quick release valves (22, 24) are disposed closely adjacent the clutch cylinder and the shuttle valve for releasing pressure in the clutch cylinder line. An adjustable drag regulator (16) and air supply poppet valve (17) is connected between the air source and the shuttle valve (21) and is actuatable to supply low pressure to the drum drive clutch cylinder (25) for dragging. A momentary return of the drum from dragging to full speed is accomplished by momentarily shifting the said pressure graduating valve (15) to an out-of-neutral mode to supply high pressure to the drum drive clutch cylinder (25). A normally open relay valve (20) is disposed in the line between the regulator (16) and poppet valve (17) and one side of the shuttle valve (21).

Abstract: The engine of a mobile power crane-excavator is utilized as a source of heat to soften grease so that it may be applied to the open gears on the machine, even at low ambient temperatures. Heated water from the vehicle engine is caused to flow in heat transfer relationship with cold grease through a multi-conductor hose to provide a pre-heat of the grease. The heated water is caused to heat a metallic nozzle through which the pre-heated grease flows, thus creating a final heating of the grease up to the desired temperature. Air supplied through the nozzle causes the grease to be sprayed onto the gear. The remote supply tank for the grease may also be pre-heated with hot water from the vehicle engine.

Abstract: A loading and conveying machine has crawler treads and a frame extending forwardly thereof. A conveyor extends from the front to the rear of the machine. An apron is pivotally mounted at the front of the frame and receives material from a loading implement and deposits it onto the conveyor. The front end of the conveyor is pivotally mounted to the apron and arcuately moves about the apron pivot axis when the apron is raised or lowered. The axis of apron-conveyor pivotal mount is removed from the center of rotation of the front end of the conveyor and spaced rearwardly and downwardly therefrom. The distance between the rear apron edge and the axis of apron-conveyor pivotal mount is greater than the distance between the said edge and the center of rotation of the front end of the conveyor. The axis of apron-conveyor pivotal mount is disposed in a transverse vertical plane which is positioned between the rear apron edge and the center of rotation of the front end return portion of the conveyor.

Abstract: A crane-excavator or the like has a boom, a saddle, a translatable stick and a digging implement. A stick cylinder and implement cylinder are provided. The ends of the stick and implement cylinder rams are connected to common lever arms which are pivoted to the stick on a transverse axis which is offset from the ram-lever connections and form the stick center line. The lever arms are connected to the digging implement in a manner so that the combined forces from both rams are transmitted to the implement to pivot the latter about its axis. The simultaneous movement of the stick cylinder ram and the implement cylinder ram causes the stick to extend or retract, thus causing a shift of the implement-stick pivot axis relative to the saddle. The implement may be raised or lowered even when the stick ram is fixed in length.

Abstract: Pneumatic actuation of an over-center clutch by a main control valve and fluid motor in the direction to engage the clutch is prevented by one or more safety lockout control valves each diverting the pneumatic pressure fluid from the main control valve to actuate the fluid motor in the direction of clutch disengagement while connecting the main control valve to drain. A single operative fluid pressure is employed.

Abstract: A material loading and conveying machine has an openended scoop for gathering and containing loose material, and a conveyor for receiving material from the scoop. The open rear end of the scoop abuts a curved backstop plate having a center of curvature on the axis about which the scoop is raised or lowered. In addition, the lower portion of the backstop plate is fixed to the machine, while the upper backstop portion normally abuts the lower portion but is selectively raisable to form a gate which meters the flow of gathered material from the open rear end of the raised scoop onto the conveyor.

Abstract: A carrier-mounted crane is provided with inner and outer boom sections which are securable together at upper and lower connections. When the outer boom is to be pivotally folded beneath the inner boom, the lower connection comprises a folding compound arm extending between the boom sections and pivotable intermediate its ends. When the upper boom connection is released and the outer boom folded under, its main pivot connection to the compound arm shifts longitudinally away from the inner boom section, thus effectively moving the outer boom away from the carrier. The tip or outer end of the folded outer boom will thereby remain free of interference with the carrier elements.

Abstract: A loading and conveying machine has crawler treads and a frame extending substantially forwardly thereof. A conveyor is mounted for pivotal movement about a horizontal axis and extends rearwardly from ahead of the frame to the back of the machine. An apron is pivotally mounted at the front of the frame and receives material from a loading implement and deposits it onto the conveyor. The machine has an approach angle providing a space defined by a ground plane and a forwardly and upwardly inclined plane tangential to the arc described by the front of the treads and extending through the lower front frame corner. The apron is angularly adjustable, and furthermore, the apron pivot is vertically shiftable to thereby change the apron attitude so that it can be wholly positioned above the inclined approach plane without obstruction by the conveyor.

Abstract: A loading and conveying machine has crawler treads and a frame extending forwardly thereof. A conveyor extends from the front to the rear of the machine. An apron is pivotally mounted at the front of the frame and receives material from a loading implement and deposits it onto the conveyor. The front end of the conveyor is pivotally mounted to the apron and arcuately moves about the apron pivot axis when the apron is raised or lowered. The joined conveyor and apron may also be adjusted together by vertically moving the apron pivot axis. The midsection of the conveyor is articulated so that the conveyor framework is separated into front and rear segments which are independently movable relative to each other and to the machine frame.

Abstract: A material handling device, such as a crawler type crane-excavator, is provided with a fail-safe brake having a piston which is normally spring biased into brake engaging position and which is moved to brake release position by a positive control. A port in the piston end of the brake housing is connected to an external source of pressurized air. A passage through the piston rod permits flow of this air to the opposite piston side, thereby equalizing the air forces thereon. The air intimately contacts the brake elements and biasing springs and is discharged from adjacent the springs to the outside through a one-way exhaust valve. When maximum purging is desired, the air discharge is disposed in the lowermost portion of the brake housing. In addition, the pressurized air may be conditioned and also provided with a lubricant or the like therein to help maintain proper brake functioning and reduce the possibility of corrosion of the brake parts.

Abstract: A control system for crane-excavators and the like wherein a metering valve is connected by fluid lines to the control cylinder for the load carrying member, such as a boom or dipper arm. A check valve and a spring biased relief valve are disposed in the fluid line on the down side of the external force created by the weight of the load carrying member on the cylinder. To prevent pressure peaking in both the upside and downside lines, as well as improper check and relief valve operation when the metering valve is moved to neutral, the metering valve is constructed to connect the downside line to the drain tank when the valve is in neutral position.