US PATENT SUBCLASS 338 / 117
.~ Slidable coextensive helical and linear contacts


Current as of: June, 1999
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338 /   HD   ELECTRICAL RESISTORS

68  DF  MECHANICALLY VARIABLE (E.G., RHEOSTAT) {24}
117.~ Slidable coextensive helical and linear contacts


DEFINITION

Classification: 338/117

(under subclass 68) Subject matter wherein a resistor whose element is usually a cylindrical helix presents a cylindrical helical contact portion of one turn or less on the surface of the element or a cylindrical helical row of taps of one turn or less electrically connected to the resistance element to a linear contacting member or linear row of taps extending alongside and coextensive with the helical contact portion or row of taps, the helical contact portion or row of taps being

rotatable to move the point of contact along the length of the helical contact portion or helical row of taps and along the length of the linear contacting member or linear row of taps; or wherein a resistor whose element is usually a cylindrical helix presents a linear contact portion on its surface or a linear row of taps electrically connected with the resistance element to a cylindrical helical contacting member of one turn or less or to a cylindrical helical row of taps of one turn or less or to an elongated flat twisted contacting member, the twist being through 1805 or less, the contacting member or helical row of taps extending alongside and coextensive with the linear contact portion or linear row of taps, and being rotatable to move the point of contact along the length of the linear contact portion or linear row of taps and along the length of the helical or twisted contacting member or along the length of the helical row of taps.

(1) Note. In this subclass the point of contact moves along the length of both contacting members upon rotation of one of the members, while in subclasses 143+ below the point of contact moves along one of the members, namely the helical resistance element and remains fixed on the other member, namely the contact upon rotation of the helical resistance or the contact.

SEE OR SEARCH THIS CLASS, SUBCLASS:

143+, for a variable resistor whose contact moves along the turns of a helical resistance element. See also (1) Note above.