RS20100572A - Theft prevention security lock for the sewer drain grates, covers of sawage and water manholes and covers of other underground utilities for - Google Patents

Abstract

Invention herewith described refers to the theft prevention security lock for the sewer drain grates, covers of sewage and water manholes and covers of other underground utilities designed for various applications. According to one method of application, the security lock (1) consists of a compact assembly with steel plates (4, 5) and vertical side plates (14, 15) and in the top plate (4) there is the opening (6) with a longitudinal slot (6’) made for the right key (7) and with in the lower plate (5) built-in lock (13) with the hook (12) entering the wall of the drain (3). According to other method of application, the lock (1) is placed into the barrel shaped housing (K) attached to the lower part of the parallelepiped cover (20) or a round cover (21) and partially converted to two slanting partitions (29), with projections (30), forming an opening (31) in the form of swallow tail and two spaces of different sizes, within the larger space, in a hole, there is a lock (13) with a rotary hook (12) that, when locked by the key (7), enters the wall of the grate (2) of the drain (3). The key (7) with the hollow conical head (9) and the hexagonal base has on two conical sides of the head (9) two transverse cuts (10) for the key (7) passage through the hole (31) to set on the lock (13) with the rotating hook (12). The further implementation of the security lock (1), when locking the grate (2) of the drain (3), the vertical arm of the tooth (23) is firmly connected to a rib of the grate (2), and the horizontal arm enters underneath the frame (24) of the grate (2), and in the hole in the grate rib (2) there is placed the hexagonal lock (13) with a hook (12) to lock. The locking is performed by turning the key (7) in the lock (13) for 90 ° to one side or the other when the rotating hook (12) enters underneath the frame (24) of the grate (2).