| 摘要 |
FIELD: hinge joint of cover with frame. SUBSTANCE: the joint has two ears under the cover, one of which is furnished with a lug, vertically positioned tab rigidly coupled to the wall of the mentioned ears and held between the two mentioned ears by means of a dismountable hinge pin; the frame wall has a recess engageable with the lug in such a way that in the upper open position of the cover the mentioned lug drops into the recess and locks or interlocks the cover in this position. The invention finds its application for closing manufacturing holes made in roadways of streets and roads. EFFECT: prevented spontaneous and untimely closing of open covers, enhanced safety in use. 11 cl, 6 dwg |
