IMPROVEMENTS IN THE CONSTRUCTION OF GAS RETORT MOUTH- PIECES AND LIDS, AND IN THE FASTENINGS THEREOF
Year: 1880

page_text: PROVISIONAL SPECIFICATION left by Andrew Mackie at the Office of the
Commissioners of Patents on the 4th March 1880.
ANDREW MACKIE, of 42, Cambridge Street, Pimlico, in the County of Middlesex,
Civil Engineer.
"IMPROVEMENTS IN THE CONSTRUCTION OF GAS RETORT MOUTH-
PIECES AND LIDS, AND IN THE FASTENINGS THEREOF."
The objects of this Invention are to insure the hermetic sealing of gas retorts
and to facilitate the opening and closing of the retort lids.
To this end I provide on each side of the retort mouthpiece a vertical projecting
catch, and within each of these catches I form a groove or channel sloping outwards
so that the distance of the ends of the two channels from one another is greater at
the bottom than at the top to enable a transverse motion being given to the retort lid
by the aid of the cross-bar. Upon the outer surface of the lid I provide a rim with
two openings therein, one on each side slanting in opposite directions, and either of
the two enlarged in such a manner as to allow of the extremities of the cross bar
to pass through it, and of the cross-bar being placed in its required position. The
outer surface of the retort lid I also furnish with a projecting pin of the shape of a
sphere or spherical zone, for the cross bar to pivot thereon and adapt itself to the
apertures in the rim of the retort lid. The cross bar itself I furnish with a groove
or channel at its back for receiving the projecting pin, and with a bearing piece at
each end to prevent it from shifting longitudinally. The extremities of the cross bar
beyond the bearing pieces I form confex in cross section, and I make them bear
upon the openings in the rims of the lid, as well as upon the sides of the channels
within the projecting catches of the mouthpiece itself, thereby forcing the lid
against the mouthpiece.
For the purpose of regulating the pressure of the cross-bar upon the lid and
thence the pressure of the lid upon the mouthpiece, and securing a perfectly gas
tight joint, I insert a vertical set screw through the cross-bar between the centre of
the lid and the rim, the end of this set-screw bearing upon a projecting stop on the
outer surface of the lid and admitting of a partial revolution of the cross-bar around
its spherical pivot. This set-screw also prevents the cross-bar from coming opposite
the enlarged opening in the rim of the retort lid. I moreover furnish the cross-bar
with suitable handles for placing, displacing, and rotating the same..
On one side of the retort mouthpiece I provide two or more horizontal bearing
plates with spaces in between to receive the corresponding lugs or flat pieces with

page_text: which I furnish the lid, and I so place these lugs as to keep them clear both of the
cross-bar and the projecting catch of the mouthpiece, and make them sufficiently
wide in proportion to their thickness to admit of their supporting the lid and
cross-bar combined without the aid of a pin. By this means I am also enabled to
slide the lid both across towards and away from the face of the mouthpieco,
this latter movement allowing of the lid adjusting itself thereto, and for this
purpose I give to the apertures in the bearing plates on the mouthpiece a larger
diameter than to those in the lugs or hinge plates on the lid or conversely. By
this longitudinal movement the grit and other foreign substances which during the
operation may have lodged themselves between the mouthpiece and the lid, or on
or between the bearing surfaces of the hinge are effectually cleared out.
Upon the plain surface of the retort mouthpiece, or upon the plain surface of the
retort lid bearing thereon, or upon both these surfaces which bear upon each other,
I form a number of grooves, cavities, or recesses, separated from each other in every
direction by ridges or interstices of solid metal. By this means I greatly reduce
the area of the bearing surface and commensurately lessen the chance of gas
'escaping between the two surfaces by reason of grit or other impurities adhering to
either surface between the lid and the mouthpiece, and I also localize the injurious
effect of flaws or defective parts in the face of either.