IMPROVEMENTS IN MOULDING OR SHAPING METALS
Year: 1856

page_text: PROVISIONAL SPECIFICATION left by John Kinniburgh at the Office of
the Commissioners of Patents, with his Petition, on the 31st January
1856.
I, JOHN KINNIBURGH, of Renfrew, in the County of Renfrew, North
Britain, Foundry Manager, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN MOULDING OR SHAPING METALS," to be as follows, that is
to say:-
This Invention relates principally to the manufacture or moulding of metal
pipes or hollow or tubular articles of cylindrical contour; but it is also
applicable in the manufacture or moulding of other metallic articles more or
less resembling pipes in general structure.
In moulding and casting pipes, or similar articles, by the aid of this Inven-
tion, core bars, capable of expanding and collapsing, or contracting in diametrical
dimensions, are used. These expanding and collapsing core bars are each
composed of three, more or less, longitudinal pieces of curved metal or seg-
mental metal plates, combined together in such manner as to be capable of
forming core bars, of various diameters, by being disposed annularly with their
longitudinal junction edges in contact with each other. When three segmental
pieces are used, one of them, curved to correspond to the largest diameter to
which the core bar is to be adjusted, is a fixture as regards the adjusting
action, being fast upon a bottom or end plate. In the axial line of this plate,

page_text: or in the line from which its curvature is struck, there is a central adjusting
spindle, somewhat longer than the core bar segments, capable of revolution in
a footstep in the end plate at the bottom, and in a collar bearing in arms con-
nected to the upper end of the fixed segment. On this spindle there are keyed
two or more small eccentrics, their radii of eccentricity being coincident, so that
they give their effect simultaneously; on the same side of the spindle connecting
rods pass radially outwards from these eccentrics, & are jointed to the inner
side of a long narrow externally wedge-shaped piece, which virtually forms a
fourth segment of the core bar. This wedge piece is guided, so as to travel in
an accurate radial line, by fixed end guide pieces. The two main adjustable
segments, which are similar to the fixed segment, are each hinged, jointed to,
or otherwise put in contact with the fixed segment, one on each side, so that
their free contiguous ends are capable of folding over towards or from each
other, these contiguous edges being formed with inclines to correspond to the
inclines on the intermediate wedge piece. Short connecting rods also pass
from these adjustable segments to short radially traversing pieces, slotted or
grooved, so as to work over the central spindle as a retaining guide. When
the core bar is to be set to its moulding diameter, the central spindle is
turned until the eccentrics thereon press out the wedge piece far enough
to bring the adjustable segments into the position necessary to complete
the circle begun by the fixed segment. When the core bar is to be
removed from the newly produced casting, the central spindle is turned
in the reverse direction, so as to cause the eccentrics to draw in the narrow
wedge piece, and leave the contiguous edges of the adjustable segments
free; as the wedge piece traverses inwards further it comes in contact with
the centrally disposed pieces, which are jointed to the connecting rods of
the adjustable segments, so that the onward traverse of the intermediate wedge
piece thus causes the adjustable segments to be folded over upon their joints
and turn inwards to fully collapse the core bars diameter. The core bar
can then be at once removed with great ease. Instead of the eccentrics and
connecting rods herein-before described as employed for effecting the traverse
action of the adjustable segments, rack & pinion movements
mechanical arrangements may be used.
or other