MANWAY LIFT ASSIST

摘要

PATENT PFP:235 CA MANWAY LIFT ASSIST of the Invention The invention relates to an improved balancing aid for a pivotally mounted cover for a manhole comprising means for hinging the cover relative to the manhole so the cover may be rotated about the hinge to expose and cover the manhole; and a spring retaining means comprising a rod pivotally secured to the cover, said rod being at least partially encased by a housing, said housing containing a compression spring means which is compressed when the cover is closed; wherein the improvement comprises securing the spring retaining means by attachment means which may be removed only after the spring means is first removed.