Abstract: A hose assembly, a hose coupling and a part therefor and methods of making the same are provided, the hose assembly having a tubular insert portion of a hose coupling inserted into one end of a hose, the external peripheral surface of the insert portion having a plurality of spaced apart annular ridges and having a plurality of spaced apart annular grooves therein that are separated from each other by the annular ridges so that the insert portion has medial grooves intermediate opposite end grooves thereof, the end grooves being narrower than the medial grooves.

Abstract: A hose assembly, a hose coupling and a part therefor and methods of making the same are provided, the hose assembly having a tubular insert portion of a hose coupling inserted into one end of a hose, the external peripheral surface of the insert portion having a plurality of spaced apart annular ridges and having a plurality of spaced apart annular grooves therein that are separated from each other by the annular ridges so that the insert portion has medial grooves intermediate opposite end grooves thereof, the end grooves being narrower than the medial grooves.

Abstract: A hose assembly, a hose coupling and a part therefor and methods of making the same are provided, the hose assembly having a tubular insert portion of a hose coupling inserted into one end of a hose, the external peripheral surface of the insert portion having a plurality of spaced apart annular ridges and having a plurality of spaced apart annular grooves therein that are separated from each other by the annular ridges so that the insert portion has medial grooves intermediate opposite end grooves thereof, the end grooves being narrower than the medial grooves.

Abstract: A deflector jet servovalve including a fluidic amplifier constructed utilizing a plurality of laminae stacked one upon the other and bonded together to form an integral laminated structure. The fluidic amplifier includes a fixed ejector and a pair of receivers disposed opposed the ejector with a movable deflector disposed between the ejector and the receivers to deflect a jet stream emanating from the ejector. Conduit means is also defined in the integral laminated structure to supply fluid under pressure to the ejector and to receive any differential fluid output therefrom.

Abstract: Pressure gain compensation for a single-stage servovalve of the jet pipe type. The pressure gain compensation is provided by a separate reciprocally mounted spool having a feedback wire connected between the spool and the ejector jet. The spool has a differential pressure applied across the ends thereof from the receptors disposed opposed the ejector jet. Movement of the spool applies a force feedback to the ejector jet which is proportional to the pressure differential across the receptors and is opposite the force applied to the ejector by the torque motor to thereby compensate for pressure gain.

Abstract: A mineral mining machine having haulage drive mechanism and at least one cutter drive unit for cutting elements which may be at each end of the mining machine. The cutting elements are driven by an electric motor through a variable speed gear-train and the haulage mechanism is driven by a hydraulic motor through a gear-train. The invention provides for a torque sensing device associated with a part of each cutter drive mechanism to sense the power transmitted by the cutter gear-train and a power sensing device associated with the electric motor. The torque sensing devices are in the form of a mechanical or electrical transducer which provides a signal when the power transmitted by the cutter gear-trains exceed or tends to exceed the rated value of the cutter gears. The signal is transmitted to a hydraulic pump to control the output to the hydraulic motor and thereby effect reduction of the haulage speed.