Abstract: A solenoid for a park lock mechanism wherein an annular frame has a reduced diameter at one end and receives a bobbin with a coil wound thereon with the bobbin projecting outward of the coil at one end and defining an integral bearing positioned in the one end of the annular frame. A magnetic permeable sintered metal bushing is interposed between the integrated bearing of the bobbin and the one end of the annular frame. A plunger is received in the bobbin for sliding movement relative thereto. The plunger has a first reduced section at one end that includes an element for connecting to a shifter and a second reduce section at its other end that projects out of said bobbin. The solenoid has two operating conditions, a first condition in which no magnetic force is applied to the plunger and a connected shifter is locked, and a second condition in which magnetic force is applied to the plunger and a connected shifter is unlocked for shifting.

Abstract: A solenoid for a park lock mechanism wherein an annular frame has a reduced diameter at one end and receives a bobbin with a coil wound thereon with the bobbin projecting outward of the coil at one end and defining an integral bearing positioned in the one end of the annular frame. A magnetic permeable sintered metal bushing is interposed between the integrated bearing of the bobbin and the one end of the annular frame. A plunger is received in the bobbin for sliding movement relative thereto. The plunger has a first reduced section at one end that includes an element for connecting to a shifter and a second reduce section at its other end that projects out of said bobbin. The solenoid has two operating conditions, a first condition in which no magnetic force is applied to the plunger and a connected shifter is locked, and a second condition in which magnetic force is applied to the plunger and a connected shifter is unlocked for shifting.

Abstract: A simplified fan and brushless DC motor employs an annular permanent magnet magnetized in segments about its circumference. Each segment is oppositely radially magnetized with respect to its adjacent segments. Fan blades are located within the annular magnet. A coil comprising two electrically independent and bifilar wound windings, connected to be oppositely energized, and an electromagnet structure defining two pole pieces reside outside the permanent magnet annulus. A Hall effect device alternately energizes the separate coil windings in response to passage of the segments of the rotor magnet to alternately produce opposite magnetic fields in the pole pieces. Thus commutated, the double coil arrangement affects rotation of the rotor and the fan blades.

Abstract: An arrangement for sensing the operating condition of an alternating current machine employs a Hall switch on the stator which is subjected to the alternating magnetic field established during operation. The Hall switch has a magnetic field strength threshhold below which it will not be actuated. During normal operation of the machine, the alternating field strength will cyclically exceed the switch threshhold, thereby generating a series of pulses at the frequency of alternation of the field. Should the field strength decrease as a result of overload of the machine, a decrease in line voltage, or the like, to a level below the threshhold level of the switch, the pulse output of the switch will cease. Circuitry responsive to the absence of periodic pulses actuates an indicator circuit to warn of the faulty operation.