Patent ID: 7534065

Claim:
A system comprising an electrical device lockable to an accessory part; a guide configured to guide the accessory part in a predetermined movement direction as the accessory part moves between a locking position in which the accessory part is locked to the electrical device and a removal position in which the accessory part is removed from the electrical device, wherein the guide comprises a longitudinally extending male guide rail provided on one of the electrical device and the accessory part and a longitudinally extending female guide groove provided in the other of the electrical device and the accessory part and constituting a linear guide that longitudinally receives said guide rail within said guide groove and defines a predetermined insertion direction, wherein said locking position is defined when said guide rail is received within and engages an inner end of said guide groove, and said removal position is defined when said guide rail is removed from said guide groove, said guide having a break in at least one location inside said guide groove between the locking position and removal position, wherein said break comprises at least one mating projection provided in said guide groove in said one of the electrical device and the accessory part and at least one mating transversely extending recess provided on said guide rail on said other of the electrical device and the accessory part and engageable with one another, and at said location a force acting on the accessory part moves the accessory part in a transverse direction relative to said guide groove into a safety position wherein said mating projection engages said mating recess in which the accessory part is prevented from moving further along said guide into the removal position; and at least one latch element provide on said guide rail engageable into a detent recess provided in said guide groove for locking the electrical device to the accessory part in said locking position and operative in a first transverse direction relative to the insertion direction, wherein in the safety position the at least one projection is brought into engagement with the at least one recess in a second transverse direction relative to the insertion direction, wherein the second transverse direction is transverse to the first transverse direction.