Patent attributes
A shielded solenoid for a solenoid operated valve having a solenoid body and an annular coil of electrical wire in the solenoid body. An armature of magnetic material is rectilinearly movable with respect to the body. A magnet holder is fastened to the armature and has a permanent magnet fixedly oriented thereon. A shield member covers the magnet holder and the permanent magnet. The shield member is configured to shield a Hall effect sensor from any significant electromagnetic field produced by the coil when effecting rectilinear movement of the armature. The hollow shield member has a non-metallic plug closing one end thereof. The plug has the Hall effect sensor oriented therein to closely oppose the magnet on the magnet holder so that movement of the armature and resulting corresponding movement of the magnet will cause the Hall effect sensor to produce a signal indicative of movement of the armature.
