GB631975A - Improvements in or relating to carriers for tunnel forms - Google Patents

Abstract

631,975. Moulding tunnels in situ. BLAW-KNOX CO. May 14, 1947, No. 13002. Convention date, May 20, 1946. [Class 20(ii)] [Also in Group XXX] A carrier for tunnel or like forms comprises a wheeled frame which runs on a track through a length of form in place, a beam which extends longitudinally above the frame and is adapted to support a form section, independent means pivoted on a longitudinal axis at each end of the frame raises and lowers one end of the beam and independent means at each end of the frame shifts one end of the beam laterally. As shown the form section carrier comprises an elongated wheeled frame 10. A central sill 11 is supported on transverse axles 15 by channels 13 and angles 14 and the sill is connected to uprights 18 which are also connected to an upper longitudinal beam 20. Jacks 25 are mounted on a platform 22 at either end of the carrier, the platforms being pivoted to tilt laterally. The jacks support a longitudinal beam 26 each end of which is raised or lowered independently by the jacks. Hand pumps 29 for operating the jacks are mounted at the base of the jacks. A channel section 30 mounted on each platform passes freely through channels in beams 20 and 26 and is moved laterally by screws 31 passing through the fixed beam 20, thus adjusting the beam 26 laterally. In operation, for casting concrete, the ends of the form section 12, are supported on jacks 39 and the concrete is moulded round the outside of the forms. To strip the concrete, the carrier is run into position, the door is taken from the side jacks 39 by raising jacks 25 into contact with the crown 33 and then the pivoted side members 34, 35 are collapsed by retractors 37 pivotally secured to the beam 20, the jacks 25 are lowered and the crown 33 collapsed so that the whole of the form is ready to be transported away leaving the concrete tunnel in position.