IMPROVEMENTS IN KILNS AND APPARATUS EMPLOYED IN THE MANUFACTURE OF BRICKS
Year: 1868

page_text: PROVISIONAL SPECIFICATION left by William Robert Lake at the
Office of the Commissioners of Patents, with his Petition, on the
18th February 1868.-A communication from abroad by Charles L.
Cornish and John McDonald, both of the City and State of New
York, United States of America.
I, WILLIAM ROBERT LAKE, of the "International Patent Office,"
No. 8, Southampton Buildings, Chancery Lane, in the County of
Middlesex, Consulting Engineer, do hereby declare the nature of the
said Invention for "IMPROVEMENTS IN KILNS AND APPARATUS EMPLOYED IN THE
MANUFACTURE OF BRICKS," a communication, to be as follows:-
My improvements relate to a method of burning or baking bricks,
tiles, and other articles by passing them on trucks or moving platforms
through a long tunnel provided with means for regulating the tem-
perature, whereby the bricks or other articles are heated and cooled
gradually during their passage through the tunnel.
The said improvements consist chiefly in the peculiar construction
of the kiln or tunnel; in the means for effecting the gradual heating and
cooling of the bricks therein; in the novel construction of the trucks or
platforms for carrying the bricks; and in the devices for controlling the

page_text: motion of the trucks, and for adjusting them in any desired position in
the kiln. A fire is made in each truck or platform as the same arrives
opposite apertures formed in the side walls of the tunnel, which is
provided with a door at each end to allow the trucks to enter or leave
the tunnel upon rails which extend through the same. The side
apertures are formed about midway between the two ends of the tunnel,
and each truck or platform of bricks is gradually warmed as it passes
from the entrance end to these apertures, the temperature gradually
diminishing from such apertures to the other end of the tunnel. The
bottom of the tunnel may be inclined so that the trucks or platforms are
impelled through the same by gravitation, or the said bottom may be
made horizontal and power applied to move the trucks or platforms.
The latter are constructed with flanges which project downward into
sand or other loose material lying in the bottom of the tunnel. By this
means cool air may be caused to circulate below the trucks or platforms
without coming in contact with the bricks. A suitable chimney is
erected at one end or at some other convenient part of the kiln. Each
truck is provided with a rack which gears into a toothed wheel on a
shaft extending through the side of the tunnel. The said shaft carries
on its outer end another wheel which gears into a toothed pinion or
worm whereby the shaft can be turned to check and regulate the motion
of the trucks. The kiln or tunnel is preferably constructed of brick
with parallel side walls; these walls should be built double with a
central air space. The roof of the tunnel is arched and is also built
double with an air space between its two portions. The two sides are
connected by strong tie rods which extend across the tunnel and resist
the thrust of the arched roof. The foundation of the tunnel should be.
constructed of strong masonry to support the rails which may be'
extended for any required distance beyond the ends of the tunnel. The
doors at the ends of the tunnel are preferably made to slide in vertical
frames, and are provided with balance weights so that they may be
readily opened and closed when the trucks are admitted or discharged.
The trucks or platforms are made of nearly the same width as the interior
of the tunnel with their edges fitting closely together. The wheels of
the said trucks should be flanged or grooved to keep them properly.
upon the rails. The side flanges of the trucks or platforms extend
downward between the side walls of the tunnel and the outer rails.
The cold air circulating below the trucks prevents their being injured
by the fire and also prevents the overheating of the lower ranges of the

page_text: bricks carried upon the said trucks. When the tunnel is inclined the
upper surface of the trucks or platforms should be made horizontal, or
should be constructed with a series of horizontal steps or planes so that
the bricks may be stacked properly upon the same. The bricks are
arranged on each truck in such a manner as to form the archway across
the same for the fire corresponding with the apertures in the side walls
of the tunnel. The said apertures are provided with doors which are
conveniently arranged to allow access to the said archways for lighting
and managing the fires. Sight apertures may also be formed in the
side walls to allow the progress of the burning to be ascertained. If
the bottom of the kiln or tunnel is made horizontal I prefer to propel
the trucks through the same by means of an endless chain driven by
any suitable machinery and power. Instead of placing the rails on the
bottom of the tunnel the trucks or platforms may be provided with
rails arranged to pass over a series of grooved rollers on the bottom of
the tunnel. The chimney is preferably connected with the kiln at
about the level of the upper surface of the trucks or platforms, so that
the heat may act more effectually upon the upper ranges of bricks.