Abstract: A method for automatically operating a dredge having a swingable and elevatable ladder with a cutting head having a speed comprising the steps of: providing an automatic swing sequence; providing a cutter head rate control; and providing an automatic ladder raise control sequences. A dredge in which this method is used is also disclosed.

Abstract: A valve casing is provided with a part-spherical interior sealing surface and with three valve ports each open from the outside of the casing and through the part-spherical sealing surface thereof. A part-spherical valve body or ball is mounted in concentric very slightly spaced relation to this sealing surface of the valve casing. The valve body carries a valve seal structure and is provided with a valve body passage extending through the valve body. The valve body is rotatable within the valve casing between: (1) a first position wherein said valve body passage provides a passageway between a first and a second of the ports and said valve seal structure is in sealing relation to the valve casing sealing surface around a third of said ports; and (2) a second position wherein said valve seal structure is in sealing relation around said first port and said valve body passage provides a passageway between said second and third ports.

Abstract: A fluid velocity measuring device which when placed in a freestream fluid flow causes vortices to be formed at a frequency proportional to the flow rate of the fluid. Sensors on the device generate electric signals with frequency proportional to the rate of vortex creation and with relative mean amplitudes indicative of fluid flow direction. Electric circuitry translates the electric signals into indications of fluid speed and direction.

Abstract: A pump pressure control device includes a slidably mounted throttle control cylinder having a piston connected to a pump engine throttle to vary the speed of the engine. One side of the piston in the throttle control cylinder is open to pressure from an accumulator having a diaphragm or bladder therein. The accumulator, on the side of the bladder opposite the side open to the control cylinder, is precharged to a desired pressure. The other side of the control cylinder piston is open to the pressure in the pump output line which it is desired to regulate. The regulated pump discharge pressure is adjusted by sliding the control cylinder with respect to a fixed base. A directional flow valve functions to reverse the connections to the throttle control cylinder when the discharge pressure drops below a predetermined minimum.

Abstract: A fire hydrant is designed to break away at the point of the coupling between the upper and lower standpipes when hit by a moving vehicle or the like, to reduce the chance for damage to the hydrant, the vehicle and possibly to the occupants of the vehicle. A valve push rod extends from a valve operating nut at the top of the hydrant down to operable connection with a hydrant valve so that the valve can be opened when water is to be delivered through the hydrant. To provide a breakaway connection for the push rod, a semi-cylindrical frangible coupling sleeve connects an upper valve rod section to a lower valve rod section in about the same horizontal plane as the upper and lower standpipes are coupled to each other. Then when the upper standpipe is broken away from the lower standpipe, the frangible coupling sleeve will also break, allowing separation of the upper valve rod section from the lower valve rod section without substantial danger of damage to the hydrant.