INSPECTION MAN-HOLE Russian patent published in 1999 - IPC

FIELD: construction engineering. SUBSTANCE: inspection man-hole has body with through-openings in its side wall together with supporting shoulder, supporting pad, and recesses. Also provided is cover with through-holes and protruding cantilevers which interact with recesses in body, and locking device. Through-holes in cover and through-openings in body are provided with supporting and turning axles with levers which engage in turning with at least one of supporting and turning axles. Geometric axes of supporting and turning axles are crossing in space limited by cover and body. Supporting and turning axle of cover is made in the form of curved lever having locking slot fir engagement with supporting and turning axle of body. Curved lever can be made either integrally with body or as separate part secured stationary with respect to supporting and turning axle. Aforesaid embodiment of inspection man-hole and its cover prevents uncontrolled opening of man-hole cover under moving vehicle which adds safety to motor road traffic. In addition, components of cover locking device are robust and functioning reliably and prevent penetration of dirt inside man-hole. EFFECT: higher efficiency. 7 cl, 4 dwg