IMPROVEMENTS IN THE DOORS OF PUDDLING FURNACES, AND IN FASTENINGS FOR THE DOORS OF PUDDLING FURNACES, HEATING FURNACES, MILL FURNACES, FORGE FURNACES, AND OTHER LIKE FURNACES
Year: 1877

page_text: PROVISIONAL SPECIFICATION left by Jonathan Edwards at the Office of
the Commissioners of Patents on the 12th October 1877.
JONATHAN EDWARDS, of Prince's End, Tipton, in the County of Stafford, Iron
Founder. "IMPROVEMENTS IN THE DOORS OF PUDDLING FURNACES, AND IN
FASTENINGS FOR THE DOORS OF PUDDLING FURNACES, HEATING FURNACES, MILL
FURNACES, FORGE FURNACES, AND OTHER LIKE FURNACES."
My Invention has reference to the sliding doors of the furnaces enumerated, and
other like furnaces; and my said Invention consists principally of the construction
and arrangement herein-after described of the parts of a. fastening for the said
sliding doors, whereby the fastening and releasing of the said doors may be
effected with great facility; the doors are held very firmly against the face of the
door frame, and the use of wedges for fastening the door is unnecessary.
I will describe my Invention as applied to the sliding door of a puddling
furnace.
I joint to the front of the door frame of the furnace, and at about the middle
thereof, a lever fastening, consisting of three sides of a rectangular frame. The free
ends or extremities of the two shorter sides of this frame-like fastening carry pivots
or centres which turn in open bearings made in brackets at the front of the door
frame. The other ends of the said short sides of the frame are connected together
by the longer side of the frame, which said longer side constitutes a handle by which
the lever fastening may be moved for fastening or unfastening the door. The free
ends of the said short sides of the lever fastening are expanded into a circular
figure excentric to the pivots on which the fastening turns, the said expanded and
excentric parts constituting cam-like ends to the lever fastening. When the
sliding door has been lowered in its frame, and the lever fastening brought into a
horizontal position, the cam-like ends of the said fastening bear forcibly against
the door near its edges and force the said door towards and hold it firmly against
the face of the door frame. In order to release the door the lever fastening is
Lifted from the horizontal position described to a nearly vertical position. By this
motion the acting parts of the excentric or cam-like ends of the fastening are

page_text: removed from the door, and the door is released and may be raised. When the
lever fastening is lifted into its unfastening position it is held in that position by
a lever catch at one side of the door frame. On the under side of this catch is a
notch, and on one of the shorter sides of the lever fastening is a projection
which is inclined or bevelled on its upper face. When the lever fastening is lifted
from its horizontal position its projection strikes against and raises the lever catch;
and when the lever fastening is at the proper height to unfasten the door the said
catch falls and its notch engages with the projection on the said lever fastening and
holds the latter in its raised position.
When a clear space is required at the front of the furnace door for repairing the
furnace or otherwise, its fastening mechanism may be readily removed by lifting its
pivots from the open bearings in the brackets at the front of the door frame. The
lever catch may also be removed by withdrawing its joint pin.
I construct the stoppers by which the rabble holes in the doors of puddling fur-
naces are closed in the following manner :-I make the front of the stopper of a
plate having at its back a small chamber, the said plate and chamber being made in
one piece. The said small chamber has the figure of and fits closely in the rabble
hole in the sliding door of the furnace. The said small chamber in the stopper is
filled with fire-clay.
When the stopper is in its place for closing the rabble hole, the edge of the said
rabble hole is preserved by the fire-clay lined chamber of the stopper from the
direct action of the heat of the furnace, and the said edge of the rabble hole is
thereby kept comparatively cool, so that during the puddling process the said edge
of the rabble hole is better fitted to resist the wearing action of the rabble against
it than when the said edge has been exposed to the heat of the furnace as when
ordinary stoppers are used.
In order that the stopper need not be detached from the furnace door when the
rabble hole is required to be opened, I hang the said stopper on a hook-like peg
above the stopper hole, an eye at the summit of the front plate of the stopper
taking upon the said peg. Upon this peg the stopper is capable both of sliding and
swivelling. To remove the stopper from the rabble hole the stopper is drawn for-
ward, its eye sliding on the peg until the lined fire-clay chamber of the stopper is
withdrawn from the rabble hole; the stopper is then turned on the peg through a
quadrant, and made to rest on a foot or support on the front of the door. The
rabble hole is thereby left clear for the rabble.
The stopper may, if required, be completely disconnected from the door by
drawing its eye from off the hook-like peg.
In order to reduce the bulk of metal around the rabble hole inside the furnace
door, I make the outer edges of the metal block fixed around the inside of the said
rabble hole with inclined or bevelled edges instead of square edges as usual. The
edges of the fire-clay lining bricks which are situated around the said block are
correspondingly bevelled or inclined so as to fit closely against the inclined edges of
the rabble hole block.
The fastening herein first described, as applied to a puddling furnace door, may
also be applied to the sliding doors of heating, mill, and forge furnaces, and other
furnaces having sliding doors.