Magnetically acting lock and key

Claim 1

In a lock comprising a barrel which is adapted to receive a key and, when the proper key is applied to the barrel, is rotatable about an axis of the barrel, an obstructing member which is movable longitudinally of the axis of rotation of the barrel between a first position in which the obstructing member obstructs movement of the barrel to operate the lock and a second position in which the obstructing member does not obstruct said movement of the barrel and a plurality of magnetic elements which, at least in the absence of the key, engage between the barrel and the obstructing member to prevent movement of the obstructing member relative to the barrel from its first position to its second position, the improvement wherein the magnetic elements are in the form of rolling elements, the barrel has an elongate keyway to receive the key, the obstructing member is in the form of a sleeve and surrounds the barrel, the barrel and the obstructing member collectively define a plurality of channels in which the magnetic elements are disposed and along which the magnetic elements are movable by a magnetic field of the proper key to releasing positions where they permit movement of the obstructing member from its first position to its second position, each of said channels is formed partly in the obstructing member and partly in the barrel and the formations in the barrel which constitute part of each channel are longer thans the corresponding formations in the obstructing member.