Apparatus for troweling pipe linings of mortar

Claim 1

APPARATUS FOR TROWELING COATED INTERIOR SURFACES OF CONDUITS AND THE LIKE, COMPRISING: A SUBSTANTIALLY FRUSTO-CONICALLY SHAPED TROWELING ELEMENT FORMED OF AT LEAST ONE RESILIENT SHEET OF MATERIAL SHAPED TO CONFORM TO A CONE, THE LARGER AND TRAILING END PORTIONS OF SAID ELEMENT BEING FREE RESILIENTLY TO ENGAGE UNDER PRESSURE AND TO SMOOTH THE CONDUIT COATING, WHILE THE SMALLER END OF SAID ELEMENT COMPRISES THE LEADING END THEREOF, SIDE EDGE PORTIONS OF THE SHEET MATERIAL BEING IN CIRCUMFERENTIALLY AND RELATIVELY SLIDABLE OVERLAPPING RELATION; MEANS FOR MOUNTING THE LEADING END PORTIONS OF THE ELEMENT WHILE PERMITTING SUCH RELATIVE CIRCUMFERENTIALLY SLIDABLE RELATION, SAID MEANS MOUNTING THE LEADING END PORTIONS INCLUDING A CIRCUMFERENTIALLY EXTENDING INNER MEMBER LENDING STIFFNESS TO SAID LEADING END PORTIONS; AND SPRING MEANS WITHIN SAID LEADING END OF THE ELEMENT AND HAVING OPPOSITE ENDS RESPECTIVELY CONNECTED WITH RESPECT TO SAID EDGE PORTIONS, SAID SPRING MEANS BEING TENSIONED IN A DIRECTION TENDING TO SLIDE SUCH OVERLAPPING EDGE PORTIONS RELATIVE TO EACH OTHER CIRCUMFERENTIALLY OF THE TROWELING ELEMENT IN A DIRECTION TO EXPAND SAID ELEMENT, THE SPRING CONNECTIONS INCLUDING SLIDABLE MEANS ACCOMPANIED BY PORTIONS RESTRAINING SUCH SLIDABLE MEANS TO MOVEMENTS GENERALLY CIRCUMFERENTIALLY OF THE TROWELING ELEMENT.