Highway device, in particular manhole, with frame and plug with backward movement relative to the frame to ensure the closed position of the plug in the frame

Abstract

A manhole includes a frame and plug, which moves backward relative to the frame, to ensure the plug reaches a proper closed position in the frame. A first end of a self-locking arm of the structure is pivotally mounted to the frame, and can slide in a fixed guiding groove. The first end of the arm bears on a fixed stop of the frame during tilting of the plug toward the closed position of the frame. The arm moves the plug backwards and so the plug correctly closes the opening of the frame.

1 .- 14 . (canceled) 
     
     
         15 . A manhole comprising:
 a rectangular frame having first and second side walls and first and second end walls defining an opening in the frame, a first plug having a first side that is pivotally mounted to the first end wall of the frame;   a first hinge between and hingedly connecting the first end wall of the frame and the first plug, and having play, for tilting the first plug between an upright position, providing access to the opening of the frame, and a closed position, in which the first plug bears on an inner peripheral seating wall of the frame, fitting into the frame;   a first jack assisting in opening and closing of the first plug and pivotally mounted between the first plug and the frame;   a first self-locking arm having first and second ends and pivotally mounted between the first plug and the frame, parallel to the first jack, for locking the first plug in the upright position, the first end of the first self-locking arm being pivotally mounted to the frame;   a first linear guiding groove secured to the frame and extending below the seating wall of the frame, parallel to the seating wall; and   a first stop secured to the frame, perpendicular to the second end wall of the frame, wherein:
 the first end of the self-locking arm is pivotally mounted to the frame and is slidable in the fixed linear guiding groove so that the first end of the self-locking arm approaches the second end wall of the frame during tilting of the first plug toward the closed position of the first plug, and 
 the first end of the self-locking arm bears on the first stop during tilting of the first plug toward the closed position of the first plug, causing the first plug to withdraw, toward the second end wall, adjacent to a hinged side of the first plug, so the first plug closes the opening of the frame. 
   
     
     
         16 . The device according to  claim 15 , wherein:
 the first self-locking arm has a determined length and is pivotally connected at a fixed location of the first plug so that, by bearing of the sliding first end on the first stop, the first self-locking arm keeps the first plug in a half-open safety position, relative to the frame; and   the first self-locking arm causes the first plug to withdraw toward the second end wall of the frame, while pressing on the first plug, in the half-open position, when the first plug is tilted toward the closing position, closing the opening of the frame.   
     
     
         17 . The device according to  claim 15 , wherein the first plug has the shape of a right triangle, and a single first self-locking arm is hinged under the first plug, near a straight side of the first plug, adjacent to a side of the first plug that is hinged to the frame, and to a corresponding one of the first and second side walls of the frame. 
     
     
         18 . The device according to  claim 17 , comprising:
 a second plug having the shape of a right triangle;   a second hinge between and hingedly connecting the second end wall of the frame and the second plug, having play, for tilting the second plug between an upright position, providing access to the opening of the frame, and a closed position, in which the second plug bears on the seating wall of the frame, fitting into the frame;   a second jack assisting with the opening and closing of the second plug, pivotally mounted between the second plug and the frame;   a second self-locking arm that is hinged parallel to the second jack, located between the frame and under the second plug, near a straight side of the second plug that is adjacent to the side of the second plug that is hinged to the frame, for locking the second plug in the upright position;   a second linear guiding groove secured to the frame and extending below the seating wall of the frame, parallel to the seating wall; and   a second stop secured to the frame, perpendicular to the second end wall of the frame, wherein:
 the second self-locking arm has a first end pivotally mounted to the frame and slidable in the second fixed linear guiding groove so that the first end of the second self-locking arm approaches the second end wall of the frame during tilting of the second plug toward the closed position, and 
 the second end of the second self-locking arm bears on the second stop during tilting of the second plug toward the closed position of the second plug, causing the second plug to withdraw, toward the second end wall, adjacent to a hinged side of the second plug so the second plug closes the opening of the frame. 
   
     
     
         19 . The device according to  claim 18 , wherein the first and second triangular plugs completely cover the opening of the frame in the closed positions of the first and second plugs. 
     
     
         20 . The device according to  claim 15 , wherein the first plug has a rectangular shape completely covering the opening of the frame in the closed position, and further comprising:
 a second self-locking arm having first and second ends and pivotally mounted between the first plug and the frame, parallel to the first jack, for locking the first plug in the upright position;   a second linear guiding groove secured to the frame and extending below the seating wall of the frame, parallel to the seating wall, and a second stop secured to the frame, perpendicular to the second end wall of the frame, wherein the first end of the second self-locking arm is pivotally mounted to the frame and is slidable in the second fixed linear guiding groove so that the first end of the second self-locking arm approaches the second end wall of the frame during tilting of the first plug toward the closed position; and   wherein the second end of the second self-locking arm bears on the second stop during tilting of the first plug toward the closed position, causing the first plug to withdraw, toward the second end wall, adjacent to the hinged side of the first plug so the first plug closes the opening of the frame.   
     
     
         21 . The device according to  claim 15 , wherein the first self-locking arm is hinged at the first end, under the first plug, around a transverse pin of the first self-locking arm, and the first self-locking arm, at the second end, is slidable around the transverse pin of the first self-locking arm and is engaged, through the first guiding groove, to slide along the first guiding groove. 
     
     
         22 . The device according to  claim 21 , wherein the first guiding groove comprises, at an end opposite the first stop, a notch for receiving the first self-locking arm, along the sliding pin, to lock the first plug in the upright position. 
     
     
         23 . The device according to  claim 18 , wherein the first and second self-locking arms are the same length, are arranged in respective planes that are perpendicular to an opening edge of the frame, are hinged at their respective first ends, under the first plug, around two coaxial pins, and are hinged at their respective second ends, opposite the frame, around respective coaxial pins. 
     
     
         24 . The device according to  claim 15 , further comprising first and second coaxial joint hinges connecting the first plug to the frame, spaced apart from each other, and parallel to the second end wall of the frame. 
     
     
         25 . The device according to  claim 15 , comprising:
 a clevis secured to part of the seating wall of the frame; and   two lugs forming knuckles, secured to the first plug, and located between branches of the clevis, wherein each of the first and second joint hinges has a cylindrical axle parallel to the second end wall of the frame and is supported by the clevis, the cylindrical pins pass through the lugs, the knuckles have an orifice larger than the cylindrical pins for movement, with play, of the first plug relative to the cylindrical pins.   
     
     
         26 . The device according to  claim 18 , wherein each of the first and second stops is adjustable in a direction perpendicular to the second end wall. 
     
     
         27 . The device according to  claim 15 , further comprising at least one elastically deformable means fastened to the seating wall, protruding from the seating wall, close to the second end wall of the frame and opposite the second end wall, adjacent to the first joint hinge for facilitating moving the first plug from the closed position. 
     
     
         28 . The device according to  claim 26 , wherein the first jack is hinged to and secured to a platen below the seating wall of the frame.