Abstract:
An improved magnetic return mechanism, especially useful in timing devices of the type including a motor means for driving a member at a given rotational velocity about a given axis and from a selected angular position, means for indicating when the member has been driven a given angular amount corresponding to a cycle time, means for releasing the member for free rotation about the given axis back to the selected angular position, and return means for rotating the member from a position angularly spaced from the selected position to the selected position. This type of return means includes a first set of permanent magnets, means for supporting the first set of magnets on the member, a second set of permanent magnets, means for supporting the second set of magnets in a generally fixed position to create a magnetic return force on the first set of magnets and a magnetic reaction force on the second set of magnets, wherein the forces combine to return magnetically the member to the selected position when the member is spaced from the selected position and is free to rotate. The improvement in this type of device includes a shifting means for allowing a preselected amount of movement of at least one of the magnets in the first and second set of magnets in response to one of the aforementioned magnetic forces, this allowed movement is generally arcuate of the given axis and is with respect to the support means of the magnet allowed to move.