Abstract: A blade sharpener having a sharpening mechanism that functions to sharpen a blade engaging the mechanism and being moved longitudinally relative to that mechanism. The sharpening mechanism is located within a hollow housing or scabbard for containing the blade, and means is provided to restrain the blade against inadvertent removal from the housing. The blade is moved into and out of the housing through a front end of the housing, and the restraining means becomes operative (automatically) when the blade is fully inserted. Locking means then functions to prevent release of the restraining means, and that locking means includes a plate movable in the longitudinal direction of the housing between locking and unlocking positions. The locking means is moved into the unlocking position by actuation of a press button located at the rear end of the housing, and automatically returns to the locking position when pressure is removed from the press button.

Abstract: A spark ignited engine of the type employing exhaust gas recirculation and stratification of the recirculated exhaust gas. The engine has at least one cylinder accommodating a piston and communicating with at least one inlet port cooperating with an inlet valve for inducing air into the cylinder, and at least one exhaust port cooperating with an exhaust valve for discharging exhaust gas from the cylinder. The engine is operated such that the recirculated exhaust gas is induced alone into the cylinder through the inlet port during a part of the engine operating time whereby recirculated exhaust gas and air are introduced through the same port, though at different times.

Abstract: A two-stoke engine comprises a cylinder accommodating a piston and having an air inlet port and an exhaust port. The exhaust port communicates with an exhaust system which includes a reduction catalyst and an oxidation catalyst. The exhaust system includes two exhaust flow paths in parallel, the first of which includes the reduction catalyst and the second of which bypasses the reduction catalyst, the downstream ends of the two flow paths being connected together upstream of the oxidation catalyst. The exhaust port is controlled by the piston or by poppet valves so that as the piston performs its downstroke the initial flow of exhaust gas is substantially through the first flow path and the subsequent flow of exhaust gas is substantially through the second flow path.

Abstract: An elongated fitting, which forms a thread as it is screwed onto the end of a conduit, has an internally threaded tubular portion at one end which receives the conduit. A stem portion on the opposite end permits coupling of the fitting to external parts. An intermediate portion is provided for rotating the fitting relative to the conduit. A longitudinal slot axially extends along the wall of the tubular portion to permit visual inspection of the amount of conduit inserted in the fitting and for lowering the tightening torque required for forming the threads on the conduit.

Abstract: A device for indicating the direction of rotation of a rotating body forming part of or associated with rotating electrical machine comprises the combination of a probe unit positioned to interrupt magnetic lines of force generated by the electrical machine, a detector for interpreting signals from the probe unit, and an indicator, which can be a center zero current meter or an oscilloscope, for displaying direction of rotation.