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.

Description

BACKGROUND OF THE INVENTIONThe present invention relates to a highways device, in particular a manhole, comprising a rectangular frame whereof the side walls and ends delimit an opening and at least one plug whereof one side is pivotally mounted relative to an adjacent end wall of the frame by at least one joint hinge.The invention is in particular but not exclusively applicable to manhole covers.In such an application, the frame is durably sealed in the ground and one or several plugs articulated relative to the frame can occupy a lowered position in which the plugs cover the opening formed in said frame or a raised position in which the plugs free the opening of the frame.Each joint hinge of a plug to the frame generally has functional play allowing the plug to be articulated to the frame without difficulty and to fit correctly into the opening of the frame delimited by its four side walls and ends to close said opening.However, each manhole cover plug is very heavy, as it is made...

AI Technical Summary

Benefits of technology

"The present invention aims to improve safety devices for plugs of highways devices by offsetting the drawbacks of existing devices. The invention provides a highways device comprising a rectangular frame with an opening, a plug, and a self-locking arm pivotally mounted between the plug and the frame. The self-locking arm has a sliding end that can come closer to the frame during tilting of the plug to its closed position, allowing it to withdraw and close the opening of the frame. The self-locking arm is pivotally mounted to the frame and can slide in a fixed guide groove to lock the plug in its upright position. The invention provides a more effective and reliable safety device for plugs of highways devices."

Problems solved by technology

However, each manhole cover plug is very heavy, as it is made from a cast iron-based material, in particular spheroidal.

Thus, such plugs are difficult to maneuver during tilting thereof between the closed and open positions of the frame and, moreover, when they occupy their raised open position, they can accidentally tilt to their closed position of the opening of the frame.

However, such a safety device has the drawback that during tilting of the plug to its closed position of the frame opening, the assistance jack exerts a force on the plug pushing it towards the end wall of the frame opposite the joint hinge, the functional play of which risks making the corresponding edge of the plug collide with the upper edge of said end wall, thereby preventing correct closing of the frame opening by the plug and risking damaging both the edge of the plug and the corresponding end wall of the frame.

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