Plastic and nonmetallic article shaping or treating: processes – With severing – removing material from preform mechanically,... – Forming continuous work followed by cutting
Patent
1995-12-19
1998-10-13
Aftergut, Karen
Plastic and nonmetallic article shaping or treating: processes
With severing, removing material from preform mechanically,...
Forming continuous work followed by cutting
264148, 264163, 26417711, 26421111, 264DIG31, 425219, 425220, 425308, 425310, 425425, 425434, B28B 507, B28B 714, B28B 1114
Patent
active
058208020
DESCRIPTION:
BRIEF SUMMARY
This invention is concerned with improvements in or relating to a roof tile making machine and its method of operation.
Concrete roof tiles are in the main formed by the well known roller and slipper method in which tile pallets are fed seriatim beneath the mortar hopper of a tile making machine, whereat when the machine is in use, mortar is fed onto the pallets to form a continuous ribbon thereon. Downstream of the mortar hopper, a cutting mechanism of the tile making machine is operated to cut the ribbon of mortar to form discrete "green state" tiles on the individual pallets which "green state" tiles are thereafter cured by conventional means.
The upper surfaces of the tiles so formed are generated by the roller and slipper and may therefore be of any desired profile across the tiles so formed. For example, the tiles may have a so-called "Bold Roll" or "Roman" profile.
The under-surfaces of the tiles, on the other hand, are formed by the pallets, that is, the surfaces of the pallets are shaped with recesses and channels to form hanging nibs, strengthening ribs and downwardly facing interlocking sidelock features of the tiles.
Often the strengthening ribs have a depth which is self-defeating in relation to their purposive intent which is to strengthen the tiles. Tests effected on cured tile sections have consistently indicated that the thin body sections have greater strength than the ribs or that size for size the proportion of the tile's strength supplied by the ribs is disproportionate to their depth. It is believed that this phenomenon is caused by the variations in compaction of the different sections of the tiles. For example, a thin body section is readily compacted to give a high strength for a particular cross-section and yet an adjacent strengthening rib formed under the same compacting pressures, applied by the same roller and slipper does not have the strength expected of it. Visual examination of the cross-section of such ribs by examination of the apparent porosity thereof has revealed that the compaction of the mortar is greatest towards the thin body portion of the tiles whilst it falls off towards the extremities of the ribs, that is the degree of compaction of the mortar in the ribs is apparently a function of the respective depths of the ribs.
The present invention seeks to overcome or at least mitigate the disadvantages of the prior art concrete roof tiles. Thus, the present invention provides a tile making machine comprising a hopper provided with a packshaft, roller and slipper, said packshaft being effective, when the machine is in use and tile pallets are fed seriatim beneath said hopper, to direct mortar onto said pallets as they pass beneath the roller and slipper to form a continuous ribbon of mortar on said pallets, characterised in that the tile making machine also comprises compaction means upstream of said packshaft, roller and slipper, which compaction means comprises a primary compaction device which, when the machine is in use and tile pallets are fed as aforesaid, directs and compacts mortar onto and/or into selected portions only of said pallets said selected portions forming, inter alia, longitudinal strengthening ribs in finished tiles.
The present invention also provides a tile making machine according to the preceding paragraph further characterised in that said compacting means also comprises a secondary compaction device wherein, when the machine is in use, and after the primary compaction device has directed and compacted mortar onto and/or into the selected portions of the pallets as aforesaid, the secondary compaction device further compacts the mortar in said selected portions only of the pallets as the pallets pass therebeneath to fully compact the mortar of the portions forming the longitudinal strengthening ribs in the finished tile as aforesaid.
Preferably in the tile making machine according to the last two preceding paragraphs, the primary compaction device comprises a multi-tined wheel arranged in use to overlie selected portions only of said pallets a
REFERENCES:
patent: 3303245 (1967-02-01), Trudeau
patent: 3776075 (1973-12-01), Matthews
patent: 4666648 (1987-05-01), Brittain
patent: 4856395 (1989-08-01), Smith et al.
patent: 5075985 (1991-12-01), Koch et al.
patent: 5080840 (1992-01-01), Jost et al.
patent: 5223200 (1993-06-01), Schulz et al.
patent: 5595698 (1997-01-01), Nicholas et al.
Aftergut Karen
Redland Technologies Limited
LandOfFree
Tile making machine and method does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Tile making machine and method, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Tile making machine and method will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-310270