Door for a mine stopping having knife-edge hinges
Number of patents in Portfolio can not be more than 2000
United States of America Patent
Stats
-
Feb 15, 1983
Grant Date -
N/A
app pub date -
Oct 17, 1980
filing date -
Oct 17, 1980
priority date (Note) -
Expired
status (Latency Note)
Importance
Abstract
A door for closing a man-door opening in a mine stopping, the door having a pair of knife-edge hinges one at each of the two upper corners of the door for mounting the door to swing about a horizontal axis adjacent the top edge of the man-door opening between open and closed positions. Each hinge comprises a horizontally extending pivot pin and a vertically extending lug comprising a relatively thin metal plate member having a hole therein adapted to receive the pivot pin, whereby the area of engagement between the pivot pin and the lug is relatively small so that corrosion on the hinge at said area of engagement does not inhibit opening of the door.
First Claim
Other Claims data not available