Pin-cushion correction apparatus for television receivers

Claim 1

A pincushion correction apparatus for a television receiver comprising first and second coil systems each including a saturable magnetic core, a ''''vertical'''' coil adapted for connection to receive the vertical deflection signal current and a ''''horizontal'''' coil adapter for connection to receive the horizontal deflection signal current, the ''''horizontal'''' and ''''vertical'''' coils of each respective system being wound in closely coupled relationship on a saturable winding portion of said magnetic core, said ''''vertical'''' coils being respectively connected in series with each other and said ''''horizontal'''' coils being respectively connected in series coils each other so that the magnetic fluxes induced in the ''''vertical'''' coils by the ''''horizontal'''' coils are directed in opposite directions in the respective coil systems, and a respective permanent magnet associated with each magnetic core for producing a magnetic flux to act with the magnetic flux resulting from the current flowing through the ''''vertical'''' coil of the system, the direction of the flux from each permanent magnet aiding the flux from the ''''vertical'''' coil during one half of the vertical deflection cycle and opposing the flux from the vertical coil during the other half of the cycle with the two systems working in an opposed relationship so that the core of one system is being driven toward magnetic saturation while the core of the other system is being driven in the opposite direction thereby lowering the amount of flux produced by the ''''horizontal'''' coil for coupling to the ''''vertical'''' coil of the system whose core is being driven toward saturation and increasing the amount of flux produced by the ''''horizontal'''' coil of the other system, the permanent magnet of at least one one of said systems being adjustable to control the amount of flux applied to its respective system.