Patent GB-1397287-A (GB)
Title: Collecting mechanisms for use with a tower furnace
IPC: B28B5/02
Filed: 1972-12-01
Abstract: 1397287 Endless-belt conveyers SELAS CORP OF AMERICA and DOW CHEMICAL CO 1 Dec 1972 [22 Dec 1971] 55734/72 Heading B8A [Also in Division F4] A collecting mechanism for use with a tower furnace having an opening in the bottom, comprises an endless belt having upper and lower courses moving horizontally beneath the opening of the furnace, a pair of drive rolls around which the belt is guided, first drive means connected to one of the drive rolls to move the upper course at a fixed speed to move material from under the furnace, a second drive means operative to exert a constant torque and means to connect it individually to sprockets at each end of the other drive roll to exert a constant traction to the lower course of the belt. The apparatus is for the manufacture of ceramic foam by dropping particles of clay through the bloating zone of a tower furnace. The bloated particles form an agglomerated mass on the belt beneath the furnace opening, which is moved at a rate determined by the thickness of the slab required. The belt 1 is supported between side chains running on sprockets on each side of the head roller 2 and tail roller 3. The belt is made of wire mesh. At the left hand end a parting agent 8 is deposited on the belt from a hopper 15, the thickness of the layer being set by scraper bar 17. The parting agent, which is a granular material with good insulating properties to protect the belt, is heated by burners 19 in zone 4 to a temperature approaching the temperature of the material falling through the furnace. As the belt moves through the collecting zone 5 a slab of ceramic foam is built up. The slab then passes through a solidifying zone 6, where it is heated by further burners 19, to an annealing zone 7. The layer 8 of parting agent breaks up at the end of the upper course and falls on to a cross conveyer 33. The head roll 2 is driven through a conventional sprocket drive by a variable-speed motor, the axle being held axially in the drive side bearing and floating in the other. The sprocket on the non-drive side is floatably keyed to the axle. The tail roll 3, Fig. 3, is similarly arranged. To provide for expansion in the length of the belt the bearings are slidably arranged, each bearing being attached by a chain 56 to a tensioning weight. The chains pass over sprockets 57 on shaft 40 so that the tension can transfer to either side if the expansion of the belt is uneven. The motor 61 drives through an hydraulic drive 62 which provides a constant torque at the output sprocket 64. Sprocket 64, through chain 65, drives sprocket 66 on shaft 67, having sprockets 68, 69 connected by chains to drive sprockets 76 at either end of the axle 43 of roll 3. Sprocket 68 and 69 drive counter shafts 71 via chains 72 and sprockets 73. Sprockets 74 on the countershafts serve to drive the sprockets 76 via chains 75. Roller sprockets 77 mounted on vertically sliding rods are spring-loaded to apply a constant tension to the lower run of chain 75. The upper runs of chains 75 pass over fixed idlers and any slack is taken up by an idler mounted on a swinging arm and positioned to rest on the chain.