Lock for door of meter cupboard - has bolts with inner and outer arms which grip respective surfaces of door frame and secured by nut which can only be removed by using special tool

摘要

The lock is provided with bolts which can only be released by special tools. Each bolt can be rotated about an axis at right angles to the door and has two radial arms, one inside and one outside the door. The inner arm (2A) grips the inner edge of the door frame (1A) whilst the outer arm grips the outer surface of the door frame. Each bolt is held in its locked position by a special nut (3A) which engages an internal screw and fits in a hole in the bolt body. This nut can only be removed by a special tool which can be inserted in the hole which houses the nut. USE/ADVANTAGE - For security of a meter in a public place. The bolts can only be released by authorised personnel.