Patent GB-1242856-A (GB)
Title: Slip-form paving apparatus
IPC: E01C19/40
Filed: 1968-08-14
Abstract: 1,242,856. Paving machines C.M.I. CORD. 14 Aug., 1968 [4 March, 1968], No. 38923/68. Heading E1G. Slip form paving apparatus 100, Fig. 4, for spreading and levelling dumped material 132 between travelling side forms comprises a rectangular subframe which is detachably suspended as by pins 106, 108 from the frame 12 of a self-propelled engine and control platform 48, Fig. 2, which carries one or more adjustable-height finishing screeds 302 which are laterally oscillated by a variable speed eccentric drive, Fig. 5 (not shown). The subframe carries:-laterally adjustable side forms (550,552); an auger assembly 130; vertically adjustable bars 134,140 controlling the flow of material; a transverse row of immersion vibrators 136 and baffle plates 138; two oscillatory finisher screeds 302,304 adjustable for height and crown profile; and optionally a floating fine finisher 146. All adjustments are effectede.g. hydraulically - from the platform 48. The frame 12 is similar to that in Specification 1,185,907 and is supported for vertical adjustment on four endless tracks 30, 32, 38, 40 by telescopic posts 26 &c on outrigger arms 18 &c., the hydraulic steering and level controls being actuated automatically by sensing arms engaging string lines 80, 82, and the outrigger arms being connected to the frame 12 by horizontal pivots and power means allowing the frame 12 to be raised for transport. Wedges, Fig. 16 (not shown) may be provided to offset one or more of the outrigger arms, and the frame 12 may have a retractable foot, Fig. 17 (not shown) so that the front track may be lifted to a higher plane -e.g. when paving up to and over a bridge. The auger assembly 130 comprises coaxial left and right hand augers, Fig. 5 (not shown) hydraulically driven at independently variable speeds. The screed 134 is suspended by four individually adjustable hydraulic cylinders, Figs. 5, 6 (not shown) spaced across the machine. The electrical immersion-vibrators 136 alternating with baffle plates 138 are carried by arms on a single transverse shaft (262) whereby they may be hydraulically raised and lowered in the material 132 (e.g. when paving ramps). The flow-control bar 140 is resiliently suspended from four hydraulic cylinders, Figs. 5, 7 (not shown) and is vibrated by a number of e.g. pneumatic vibrators (298). Each oscillatory screed 302, 304, Fig. 4 comprises a flat-walled tube terminating in a horizontally-hinged adjustable end plate 308, Fig. 8, and is suspended from four longitudinal shafts 320 &c by pairs of horizontal sliding sleeves 350 &c, and height-adjusting eccentrics 450 &c. The eccentrics on the outer pair of longitudinal shafts are adjusted by individual hydraulic cylinders 440 &c. The inner pair of longitudinal shafts have gangedtogether compound eccentrics Figs. 9, 10 (not shown) whose inner and outer sleeves are respectively actuated by a cylinder (510 and a cylinder (492) respectively adjusting the crown profile and the height of the screeds. The pairs of sleeves 350 slide on shafts 354 which can be eccentrically adjusted to vary the pitch or angle of attack of the oscillatory screeds, which are driven in anti-phase by a hydraulic motor and connecting rods. The side forms (552), Figs. 5, 11 (not shown), which are apertured for access to the finishers, are laterally adjustable against screw stops by horizontal jacks and carry angularly adjustable slip forms 598, Fig. 13 which can be pivotally raised by cylinders (608 &c). The whole machine is built in at least two longitudinally-divided parts; the paved width may thus be halved, or may be increased by inserting extension pieces. One of the side forms may carry an electrical depth gauge, Fig. 14 (not shown) comprising a vertically movable centrally-pivoted lever carrying front and rear sensing wheels running on the substrate to give an average depth reading. Similar sensing apparatus may engage the string lines 80, 82, Fig. 2 for steering and level control. The apparatus may be provided with trailing edgeform units, Figs. 18, 19 (not shown) floating on the finished paving to give a clean edge, possibly flared to allow for slump. The slip form 598 may include a groove or tongue to provide a jointing tongue or groove in the paving edge, and/or may be apertured to allow the hydraulic insertion of horizontal jointing bars, Fig. 21 (not shown) from an L-shaped magazine (830).