GB723912A - Improvements in or relating to moulding cores for use in moulding hollow concrete and similar members - Google Patents

Abstract

723,912. Collapsible cores for moulding hollow concrete members &c. EVANS, W. A. April 1953 [March 19, 1952], No. 7052/52. Class 87 (2) A core of the type described in Specification 682,305 having outer members 1 with flanges 1a, inner members 2 and end plates 11 is expanded by members 16, 17 having cam surfaces 16b, 17b which engage rollers 14 on the members 2. In modifications, the rollers may be on the members 16, 17 and the cams on the members 2, or cams on the members 2 or members 16, 17 may engage with projections on the members 2 or members 16, 17. The member 16 and members 17 may be interconnected by bars 20 welded to blocks 22 bolted to the members. The end member 17 has a hooked bar which is pulled to expand the core. When it is desired to use several cores in a line, the hooked bar on the end member 17 is fitted into a channel 24 of the adjacent member 16 and held therein by a spring (27)-urged latch. To prevent the hooked bar from being pushed back and thus collapsing the core when it is pushed into the channel to engage the latch, a bar is inserted through a hole 35 in the upper member 1 to act as a stop. The coupled cores are collapsed by inserting a bar into the end member 16 to engage the latch, and then pulling the bar. Two cores may be uncoupled by inserting a member through a hole 36 in the member 1 and disengaging the latch. Modified constructions of latch members are described and the hooked bar may be secured to the member 16 by a screw which is accessible through the opening 36. The holes 35, 36 may be secured to the member 16 by a screw which is accessible through the opening 36. The holes 35, 36 may be closed by shutters. The members 1 have ribs which engage grooves 19 in the members 16 and between lips 17a on the members 17. The core may be wrapped in paper during moulding. The members 2 may be in two parts secured by bolts 38 to enable the width of the core to be adjusted as is described in Specification 712,612.