LOCKING DEVICE FOR OBJECT TO BE PROTECTED, MAINLY FOR INSPECTION PIT HATCH Russian patent published in 2007 - IPC E02D29/14 E05B39/02 

FIELD: locking devices, preferably adapted to lock hatch doors used in engineering structures, particularly locking devices provided with members, which indicate unauthorized door unlocking.

SUBSTANCE: locking device for inspection pit hatch, which is installed in orifice made at protected object base, comprises locking member and rotary bolt. The rotary bolt includes rod with key-operated head and locking means connected to opposite end thereof. Orifice made in base of protected object additionally has socket to receive rod head with locking member made as signal member and having shape corresponding to that of the socket so that it be secured to head in axial direction and in direction of head rotation. Signal member is made as plate provided with members cooperating with head for head fixation in axial direction and in direction of head rotation. Plate member, which prevents head rotation, has surface mating to that of key socket. Fixing member is shaped as radial teeth comb in axial direction thereof. The teeth are provided with L-shaped projections created at teeth ends and enclosing the head. Space between head and teeth flange surfaces provide interference fitting thereof. Signal plate is installed to completely close access to key-operated head.

EFFECT: simplified structure and extended range of functional capabilities.

2 cl, 4 dwg