Abstract: A key guard comprises a key ring having an absent segment. A channel in the guard captures and restrains the ring to circular motion along its arc. A follower carries an interposer which intersects the channel under spring action of a spring means symmetrically positioned with respect to a central axis. The spring means may be a pair of compression springs, or a pair of spring arms acting on the follower. The ring and the key guard may be flat.

Abstract: A package comprises a cover closing an article housing formed in a baseplate. A contiguous compartment closed by a plate contains a spring assembly comprising two arc members joined at their ends and bearing on abutment members. A profiled rod inserted through a complementarily profiled opening pushes on thrust member against the abutment of the ends of the spring assembly on the abutment members so as to bring about, by symmetrical reaction, retraction of the bar supporting the bolt members. However, if a fly-weight has not previously been retracted by a magnetic field a projection engages in a groove in the fly-weight to lock the lock. The consecutive action of the magnetic field and the pressure on thrust member are applied by a key device retained at the checkout of the self-service store. The invention has one particular application in the merchandizing of prerecorded magnetic tape cassettes.

Abstract: A key ring which includes a metal ring with an open segment area for the insertion and removal of keys has the metal ring mounted in a circular guide groove of a handle portion such that the ring is rotatable therein. A latch is slidably disposed in a passage in the handle portion and spring-biased into engagement with the metal ring for locking the metal ring to prevent its rotation.Means are provided for disengaging the latch so as to permit rotation of the metal ring.

Abstract: A pair of combination locks is employed to hold the lid of a luggage case cked closed, with a left-hand lock operating as a mirror image of a right-hand lock. Principal parts of the locks, including improved dial-indexing springs (but not the dials) are interchangeable. The dial-indexing springs cooperate with the dials of left-hand and right-hand locks in the same manner, so that all of the dials have the same action.