Rotary switch for switching very large DC currents

A switch for commutating a very large DC current into the spaced parallel rails of a launcher for electromagnetic propulsion of a projectile placed between the rails, said switch comprising:

• (a) a cylindrical rotor including,
• a first conducting element extending transversely through and axially along the rotor with the radial ends thereof terminating at angularly spaced locations on the cylindrical surface of the rotor;
• second and third conducting elements extending angularly around and axially along the cylindrical surface of said rotor between the radial ends of the first conducting element with one on either side thereof;
• and
• rotor insulating members electrically isolating said conducting elements from direct electrical contact with each other;
• (b) a stator comprising,
• four brush members angularly spaced about the rotor and extending radially inward toward and axially along the cylindrical surface of the rotor, said brush members terminating in arcuate surfaces complementary to and in sliding electrical contact with the cylindrical surface of the rotor, said very large DC current being applied to first and second of said brush members which are angularly spaced by third and fourth of said brush members, each of which, in turn, is connected to one of said rails;
• and
• fixed insulating member surrounding the remainder of the rotor between the conducting elements for electrically isolating the same from direct electrical contact with each other;
• and
• (c) means for rapidly rotating said rotor from a first position in which said first conducting element completes a circuit between said first and second brush members and a second position in which the second conducting element completes a circuit between the first and third brush members and the third conducting element completes a circuit between the second and fourth brush members such that the very large DC current is commutated into the gun rails.

A switch for selectively inserting a source of a very large DC current into a series circuit including an inductor and the firing switch of an electromagnetic launcher, said switch comprising:

• a cylindrical rotor including a conducting element extending angularly around a portion of and axially along the cylindrical surface of the rotor;
• a stator including three angularly spaced brush members extending radially inward toward and axially along the cylindrical surface of the rotor and terminating in arcuate surfaces complementary to and in sliding electrical contact with the cylindrical surface of the rotor, a first of said brush members being connected to one side of the DC current source, a second of said brush members being connected to one side of the inductor and the third brush member being connected between the second side of the DC current source and said firing switch;
• and
• means for rapidly rotating said rotor between a first position in which the conducting element on said rotor completes an electrical circuit between said first and second brush members such that said DC current source is in series with the inductor and firing switch, and a second position in which said conducting element completes an electrical circuit between said second and third brush members such that said DC current source is removed from the series circuit.