Short-current protection action current adjusting method and device thereof and device for multi-pole electromagnetic release

摘要

A short-circuit protection action current adjusting method and a device thereof for a multi-pole electromagnetic release. An electromagnetic system includes an auxiliary static iron core, a second static iron core, a coil, a reset spring and a dynamic iron core; at an initial position, a first gap is formed between the auxiliary static iron core and the dynamic iron core, a second gap is formed between the dynamic iron core and the second static iron core, and the thickness of the second gap changes in the same direction along with the size variation of a release threshold; the elastic force of the reset spring changes oppositely along with the size variation of the release threshold; when a release current value is adjusted from large to small, the coil energy reduces in a quadratic relationship mode along with flowing currents and meanwhile the electromagnetic attraction between the dynamic iron core and the second static iron core is increased in a quadratic relationship mode, which is in inverse proportion to reduction of the thickness of the second gap. According to the short-circuit protection action current adjusting method and device thereof for the multi-pole electromagnetic release, adjustment of the release current value and electromagnetic attraction required by actions of the dynamic iron core are in a linear fixed corresponding relationship due to automatically achieved balance between two quadratic functions, and adjustment of the release threshold through the user is convenient, reliable and stable.