Shoring equipment

Claim 1

IN SHORING EQUIPMENT, A PAIR OF NORMALLY PARALLEL BEAMS EACH HAVING A LONGITUDINALLY EXTENDING WEB PORTION AND, A PAIR OF LONGITUDINAL EXTENDING SPACED RIBS INTEGRAL WITH THE WEB OF EACH BEAM AND DEFINING A CHANNEL SECTION OPENING TOWARD THE CHANNEL SECTION OF THE OTHER BEAM, A PAIR OF PINS TRAVERSING SAID CHANNEL OF EACH BEAM AND SUPPORTED BY THE RIBS THEREOF, ONE PIN OF EACH PAIR CONSTITUTING A PIVOT PIN AND THE OTHER A BEARING PIN, LINERALY EXTENSIBLE FORCING MEANS EXTENDING BETWEEN SAID BEAMS AND A HEAD BLOCK AND A FOOT BLOCK CARRIED AT OPPOSITE ENDS OF SAID FORCING MEANS, SAID HEAD BLOCK BEING PIVOTALLY MOUNTED ON THE PIVOT PIN FOR MOVEMENT INTO AND OUT OF BEARING ENGAGEMENT WITH THE BEARING PIN OF A PIN PAIR CARRIED BY ONE BEAM, AND SAID FOOT BLOCK PIVOTING ON THE PIVOT PIN FOR MOVEMENT IN AND OUT OF BEARING ENGAGEMENT WITH THE BEARING PIN OF A PIN PAIR CARRIED BY THE OTHER BEAM, EACH OF SAID BLOCKS BEING MAINTAINED IN A SPACED POSITION FROM THE WEB OF THE BEAM WITH WHICH IT IS ASSOCIATED BY ITS PIVOT PIN WHEN SAID BLOCK DOES NOT ENGAGE ITS BEARING PIN AND BY ITS PIVOT PIN AND BEARING PIN WHEN SAID BLOCK BEARS ON ITS BEARING PIN AND THE SURFACE OF THE BLOCK BEARING ON ITS BEARING PIN BEING ORIENTED AND ARRANGED WITH RESPECT TO SAID FORCING MEANS TO DIRECT THE LINE OF EXTENSION SUBSTANTIALLY PERPENDICULARLY TO THE BEAM ON WHICH SAID BLOCK IS PIVOTED, THE PIVOT PINS BEING DIAGONALLY ARRANGED WITH RESPECT TO EACH OTHER IN THE CORNERS OF THE QUADRILATERAL LOCATED BY THE SAID PIN PAIRS, WHEREBY SAID BEAMS MAY BE MOVED TOWARD EACH OTHER UPON PIVOTING SAID BLOCKS ON SAID PIVOT PINS AND OUT OF ENGAGEMENT WITH SAID BEARING PINS FOR INSERTION AND REMOVAL FROM BETWEEN OPPOSED SURFACES AND, WHEN SAID BLOCKS ENGAGE SAID BEARING PINS, EXTENSION OF SAID FORCING MEANS PERMITS SAID BEAMS TO SHORE OPPOSED SURFACES.