Security Device

Abstract

The invention relates to a security manhole that is secured to the mouth of an underground pipe ( 4 ) including an edge ( 2 ) and a hinged cover ( 5 ) having rising cylinders ( 6 ), a peripheral sealing gasket ( 30 ) being provided for. The cover ( 5 ) includes an opening provided with a screw fixed lid ( 8 ), one of the screws compresses a first electrical contact ( 9 ) sending a warning signal to a control centre. Underneath the lid is provided a turning part ( 10 ) pulling in an angular fashion a closing handle ( 14 ) provided onto the edge. In the closed position, said handle ( 14 ) is located on top of the plate ( 18 ) integral with said edge ( 5 ), both having an access ramp providing automatic pre-closing. The closing position is provided through a second electrical contact ( 19 ). In the opening position, the closing handle ( 14 ) is retained by retention pawl ( 15 ) hinged to the edge ( 2 ). Release is provided through a screw ( 21 ) fixed to the cover ( 5 ) upon contact with said retention pawl ( 15 ).

1 . SECURITY MANHOLE, with cover hinged to the edge fixed to the mouth of the underground pipe, assisted by means of raising and there existing a sealing joint for closure of the cover, wherein the cover comprises an opening with a peripheral stagger in which seats a plate fastened with screws, one of which exerts pressure on an electrical contact sending a warning signal, there existing beneath the plate a rotating piece provided with a coaxial shaft ending in a stub which fits into a housing of the closing handle linked to the edge and having a rotating pulling movement, able to adopt a position in which it is located above another plate integral with the cover, both of which are provided with a ramp for facilitating access, being able to adopt another angular position for release in which it is retained by a retention pawl; with provision being made for another electrical contact which transmits the corresponding signal to the control centre securing this closure position, there existing means which force that closure position along with means of opening from the inside in an anti-panic action from the underground pipe via radial handles to a lower extension of the actual rotating axis of the closing handle. 
   
   
       2 . SECURITY MANHOLE, according to  claim 1 , wherein a pre-closure is provided for the cover both from the outside and from the inside, consisting of a screw that is adjustable in height and fixed to the cover, which makes contact with the retention pawl which maintained the closing handle in the rotated open position, causing it to descend in order to release said closing handle so that, aided by a recovery spring, it can occupy the partially closed position, without reaching the point of acting on said electrical contact, the cover comprising a handle for pulling from the inside. 
   
   
       3 . SECURITY MANHOLE, according to  claim 1 , wherein the means which force the pre-closed or locking position of the closing handle are determined by a belt wound around a widened cylindrical segment of the shaft for rotation of said handle and whose free end is secured to a pulling spring fixed to the wall of the edge. 
   
   
       4 . SECURITY MANHOLE, according to  claim 1 , wherein the closing handle is linked to the edge by means of a support that is adjustable in height in order to control the tightening pressure of the cover on the peripheral sealing gasket. 
   
   
       5 . SECURITY MANHOLE, according to  claim 1 , wherein the vertical section of the underground pipe to which the edge is secured incorporates an access ladder consisting of a fixed section backed onto the walls of the vertical pipe and another end section that is hinged for folding onto the roof of the horizontal pipe, there existing means of retention for the folded position, along with a counterweight connected to the mobile section.