Elevating mechanisms

Claim 1

IN AN ELEVATING MECHANISM, AN UPSTANDING, ELONGATED MEMBER HAVING A CHANNEL-SHAPED, LONGITUDINALLY EXTENDING CENTRAL PORTION AND TWO LONGITUDINALLY EXTENDING FLANGES, SAID CHANNEL-SHAPED PORTION HAVING AN INTERMEDIATE PORTION AND TWO LONGITUDINALLY EXTENDING SIDE WALL PORTIONS, SAID FLANGES PROJECTING OUTWARDLY FROM THE EDGE PORTIONS OF RESPECTIVE ONES OF SAID SIDE WALL PORTIONS REMOTE FROM SAID INTERMEDIATE PORTION IN GENERALLY OPPOSITE DIRECTIONS AND HAVING FREE EDGE PORTIONS TERMINATING IN SPACED RELATION TO EACH OTHER, SAID FLANGES HAVING CHANNEL-SHAPED AND OPENING GENERALLY INWARDLY TOWARD THE CENTRAL PORTION OF SAID MEMBER, ANOTHER UPSTANDING, ELONGATED MEMBER HAVING A CHANNEL-SHAPED, LONGITUDINALLY EXTENDING CENTRAL PORTION AND TWO LONGITUDINALLY EXTENDING FLANGES, SAID LAST-MENTIONED CHANNEL-SHAPED PORTION HAVING AN INTERMEDIATE PORTION AND TWO LONGITUDINALLY EXTENDING SIDE WALL PORTIONS, SAID LAST-MENTIONED FLANGES PROJECTING OUTWARDLY FROM THE EDGE PORTION OF RESPECTIE ONES OF SAID LAST-MENTIONED SIDE WALL PORTIONS REMOTE FROM SAID LAST-MENTIONED INTERMEDIATE PORTION IN GENERALLY OPPOSITE DIRECTIONS AND BEING SLIDABLY MOUNTED IN A RESPECTIVE ONE OF SAID FIRST-MENTIONED FLANGES IN POSITION TO SUPPORT SAID LAST-MENTIONED INTERMEDIATE PORTION IN SPACED RELATION TO SAID FIRST MENTIONED PORTION PORTION, SAID LAST-MENTIONED FLANGES BEING LONGITUDINALLY RECIPROCABLE RELATIVE TO SAID FIRST-MENTIONED FLANGES, A SHEAVE ROTATABLY MOUNTED ON THE UPPER END PORTION OF SID FIRST-MENTIONED CENTRAL PORTION, AND A CABLE FOR LONGITUDINALLY RECIPROCATING SAID OTHER MEMBER RELATIVE TO SAID FIRST-MENTIONED MEMBER, SAID CABLE BEING TRAINED OVER SAID SHEAVE AND HAVING ONE END PORTION OPERATIVELY CONNECTED TO SAID OTHER MEMBER, AND ANOTHER END PORTION DISPOSED OUTWARDLY OF SAID FIRST-MENTIONED MEMBER IN POSITION TO BE LONGITUDINALLY RECIPROCATED THROUGH A PATH OF MOVEMENT EFFECTIVE TO LONGITUDINALLY RECIPROCATE SAID CABLE OVER SAID SHEAVE.