Abstract: A proportional fluid flow control hydraulic valve including a valve body in which a by-pass flow passage leads from an inlet port to a by-pass outlet port. A valve chamber is arranged between the inlet port and a regulated flow outlet port and the by-pass outlet port. The by-pass flow passage includes an annular auxiliary flow channel which extends in bypassing relationship around the valve chamber. A valve member movably mounted in the valve chamber has valve ports therein for controlling fluid flow from the inlet port and the auxiliary fluid flow channel past the valve member to the regulated flow passage. In one form, the valve member is normally disposed in balanced hydraulic equilibrium in the valve chamber to prevent fluid flow from the inlet port through the auxiliary fluid flow channel and the valve ports in the valve member into the valve chamber and thence into the regulated flow passage.

Abstract: In an ignition indicator system for internal combustion engines, a transformer is interposed in each line between the spark plug and distributor or other timing circuit. The transformer has a sensor element positioned adjacent thereto to be indirectly coupled to the transformer output circuit. Terminal means is provided for connecting the sensor element to detector means which permits analysis of the pulses for firing the spark plug. Preferably, the transformer and the high voltage portion of the ignition system is shielded by a grounded casing or sheath to minimize radiation of signals, as well as to confine any explosion of ignited gases within the casing or sheath. Access to the sensor element does not adversely affect the shielding effect of transformer casing.