Inverter transformer

Abstract

In one example of a transformer, which is used in a dc-to-ac inverter circuit for lighting an electrical discharge lamp, a construction may be employed in which a primary winding and a secondary winding are gripped on both sides by a pair of cores composed of a magnetic material. In this transformer, a spacer is employed when forming a gap between the two cores. As a result, not only does the height dimension of the transformer grow large, but there is also a risk of the magnetic flux leaking from the spacer part to the outside. In the inverter transformer of the present invention, at least one core of the pair of cores is constructed as a groove formation core 1, which has a central leg 2 and outer perimeter wall 4 in addition to a septum 3 between central leg 2 and outer perimeter wall 4, and in which groove portions 61, 71 are formed concentrically between central leg 2 and septum 3, and septum 3 and outer perimeter wall 4, respectively. The primary winding 7 and secondary winding 6 are arranged concentrically in the groove portion 71 and groove portion 61, of this groove formation core 1, respectively. The other core is formed as a plate-shaped core 8, and a closed magnetic circuit is formed in which the groove formation core 1 and plate-shaped core 8 are arranged facing each other.

Dependencies are inferred from the claim text.