Stone-dress′ing ma-chine′.
A machine for reducing to shape or working the surface of the stone ready for the final operations of grinding and polishing.
In
Fig. 5854, the cutters are attached to a rotating-wheel, and act upon the face of the stone, which rests upon a traversing-table, and is fed along to the cutters by gearing from the main driving-shaft.
In another machine, a frame travels over the stone, being carried on wheels with rubber tires, and may be moved by a hand-crank, which is connected to either the moving or dressing devices.
The cutters are clamped at the lower end of a rod, which has adjustable springs to limit its action, and is raised by radial revolving arms, which engage a lever that comes in contact with its tappet.
A machine for working moldings, figures, or ornamental devices upon stone is shown in Fig 5855.
A circular tool carrying a number of diamond points is employed This is journaled vertically in a pivoted frame, admitting a movement of translation in any desired direction, and has rapid rotation by pulleys and belting.
The work, with the model or pattern, is clamped upon a table beneath, which may be raised or lowered, and held at any hight, and the tool is, by means of handles, elevated or depressed, as required, to suit the inequalities of the work, while a jet of water is conveyed to the point where it is acting.
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Stone-cutting machine. |
Fig. 5856 is a machine for facing grindstones.
The carriage slides on horizontal ways, carrying a bar of iron at right angles to its path of movement, the alternating movements and feeding being effected by bevel gears and a screw.
The turning of the crank cases the tool to traverse from right to left across the periphery of the stone, and
vice versa. The carriage is advanced by a sliding tubular shaft.
In
Fig. 5857, the cutter-wheel is placed in a case which only
[
2396]
allows a segment to protrude, and excludes grit.
The traverse sliding surfaces and the long journal-bearing are also encased.
The rests of the journal are adjustable toward and from the stone while the traverse is effected by rack and pinion.
In
Fig. 5858, the bed
C is supported upon friction rollers, and has a rotary reciprocating motion beneath the stones, above, which are secured in a frame which has a longitudinal reciprocation.
