Abstract: A method for the purification of argon in a gas obtained as a by-product from the fractionation of air to the recover O.sub.2 and N.sub.2 is described. The argon-containing gas is fed to a single argon-rectifying column which separates oxygen and then to a conventional purification column in which the separation takes place. The apparatus for carrying out the method comprises a rectification column having the top connected to a heating compressing and cooling circuit for liquefying and recycling in the liquid state the evolved vapors; the bottom of the column is heated by a fraction of the compressed but not cooled gaseous mixture drawn from the heating and compressing section of said circuit; the end section of this latter being further connected to a conventional nitrogen-withdrawing column for feeding a portion of the oxygen-free liquefied product.

Abstract: An electromagnetic clutch device for transmitting torque from an input means to an output means. The clutch actuating means includes an electromagnetic means, a driving means, an armature coaxially disposed with the input means and threadedly connected to a driving friction ring member, said armature responsive to said electromagnetic winding and said friction ring member being allowed to adjust with respect to said armature for driving the output means. The relative position between the armature and the driving friction ring member is maintained by a retarder disposed coaxially with the armature. The retarder permits relative rotational motion between the driving friction ring member and the armature in one direction and prevents relative motion between said armature and ring member in the other opposite direction. The fail-safe feature is such that when the electromagnetic means is energized no torque is transmitted from the input means to the output means.

Abstract: An altitude compensated vacuum control system for regulating the vacuum servo mechanism of an internal combustion engine of the type having a distributor with a vacuum servo controlled advance mechanism incorporating a positive stop for maximum spark advance, a carburetor to provide a source of vacuum to operate said vacuum servo mechanism and a vacuum control valve assembly for regulating the vacuum servo mechanism of said distributor. The vacuum control valve assembly receives a spark port vacuum signal from the carburetor to maintain a predetermined vacuum spark advance as the engine begins to accelerate.