Amorphous metal transformer core and coil assembly

In an electric transformer,

• A. a preformed coil structure;
• B. a wound core of closed-loop configuration extending about a window and having joints in a localized region thereof that allow said core to be opened at said joints to permit insertion into said window of said preformed coil structure, wheresupon said coil structure surrounds a portion of said core, said core comprising superposed laminations of thin amorphous ferromagnetic strip material which extend continuously around said core from said localized joint region;
• C. said amorphous ferromagnetic laminations including predetermined portions adjacent said joints which are displaced a relatively large distance from said localized joint region to provide a wide opening into said core window for said insertion of said preformed coil structure;
• and
• D. A coating of an adhesive bonding agent applied before said displacement to the exposed lateral edges of said laminations in regions of said core not including said predetermined portions, thereby holding said laminations in correct assembled relationship when said core is opened, yet with interfering with displacement of said predetermined portions while said predetermined portions are being moved to open or reclose said joints,
• E. said predetermined portions of said core adjacent said joints being substantially free of said adhesive bonding agent during said displacement icnident to opening and reclosing said joints, thereby allowing relative movement of the laminations in each of said predetermined core portions during said displacement.