Patent ID: 6169472
Filing Date: 2001-01-02
Classification: H01C,H04N

Abstract:
A PTC thermistor apparatus for use in a circuit for demagnetizing shadowmasks of color picture tubes, comprising: a housing wherein said housing has side walls arranged vertically between a top wall and a base, wherein said top wall has attachments which protrude from a bottom surface of said top side, said protruding attachments each having an inner vertical surface essentially parallel to said housing side walls, and wherein said base has a recess located on a top surface of said base, said recess having two vertical surfaces essentially parallel to said housing side walls; a unit which contains at least two PTC thermistors that are dimensioned to be electrically identical and are electrically connected in parallel, that are thermally coupled, and that are installed in said housing, said unit having; a top end held in place by said housing attachments, wherein opposite sides of said unit facing away from one another lay flat against said vertical surfaces of said protruding attachments for support; two contact points located on said opposite sides of said unit facing away from one another, and a bottom end held in place by said housing recess wherein said opposite sides of said unit facing away from one another lay flat against said two vertical surfaces of said recess, and each PTC thermistor comprises a first electrical terminal and a second electrical terminal wherein each of said PTC thermistors has their said first electrical terminals interconnected inside of said housing, each PTC thermistor further comprises: spring contact elements partially located within said housing which are fashioned as spring sheet elements, which are concave as seen in a direction from said upper support points and said lower support points towards said unit contact points, each said spring contact element having:an upper support point located at a top end which supports said spring contact element against one of said housing side walls, a unit contact region located adjacent to said top end which electrically contacts and holds said unit at said unit contact point, a lower support point located adjacent to said unit contact region near said housing base, a piercing through region located adjacent to said lower support point which pierces through said housing base, and an extension located at a bottom end of said spring contact element which protrudes outside of said housing base.