IMPROVEMENTS IN FURNACES FOR STEAM BOILERS AND WATER HEATING APPARATUS
Year: 1876

page_text: LETTERS PATENT to Samuel Crabtree, Thomas Crabtree, and James Crabtree,
all of Manchester, in the County of Lancaster, Bleachers, Dyers, and Finishers,
for the Invention of "IMPROVEMENTS IN FURNACES FOR STEAM BOILERS AND
WATER HEATING APPARATUS.”
Sealed the 23rd May 1876, and dated the 5th February 1876.
PROVISIONAL SPECIFICATION left by the said Samuel Crabtree, Thomas
Crabtree, and James Crabtree at the Office of the Commissioners of Patents on
the 5th February 1876.
"
SAMUEL CRABTREE, THOMAS CRABTREE, and JAMES CRABTREE, all of Manchester,"
in the County of Lancaster, Bleachers, Dyers, and Finishers. IMPROVEMENTS IN
FURNACES FOR STEAM BOILERS AND WATER HEATING APPARATUS."
This Invention consists in an improved mode of admitting air to the sides of the
furnaces of steam boilers and water heating apparatus to increase the combustion
of the fuel and to consume the smoke.
In performing our Invention we leave holes in the side walls of the. furnace, and
these holes are provided with sliding dampers which can be raised and lowered at
pleasure to increase or reduce the quantity of air admitted, or to shut it off entirely.
We prefer to place one pair of holes near the firing door, and the other pair near
the bridge, by this arrangement when the holes near the firing door are closed and
the others open a bright fire is kept up near the bridge, and the smoke from the tiring
end is entirely consumed before it gets to the bridge. By this means a bright clear
fire can be kept up with the commonest refuse coal, and with very little labour.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Samuel Crabtree, Thomas Crabtree, and James Crabtree in the Great
Seal Patent Office on the 2nd August 1876.
SAMUEL CRABTREE, Thomas Crabtree, and James CRABTREE, all of Manchester,
in the County of Lancaster, Bleachers, Dyers, and Finishers. "IMPROVEMENTS IN
FURNACES FOR STEAM BOILERS AND WATER HEATING APPARATUS."

page_text: This Invention consists in an improved mode of admitting air to the sides of the
furnaces of steam boilers and water heating apparatus to increase the combustion
of the fuel, and to consume the smoke.
In performing our Invention we leave holes in the side walls of the furnace, and
these holes are provided with sliding dampers which can be raised and lowered at
pleasure to increase or reduce the quantity of air admitted, or to shut it off
entirely.
And in order that our Invention may be fully understood and readily carried
into operation we will proceed to describe the accompanying Sheet of Drawings,
reference being had to the figures and letters marked thereon.
433
Fig. 1 is a front elevation of a steam boiler furnace of the ordinary construc-
tion to which our improvements are applied, and Fig. 2 is a side view of the
same; both these views are in section.
a, a are the side walls of the furnace; b, the grate bars; and c an ordinary egg-
ended boiler. On each side of the furnace are two cast-iron plates d, d, with six
or any other convenient number of perforations through them, and corresponding
openings are made in the side walls a, a. The lowest row of perforations is placed
a little above the level of the grate bars b to convey the air to the under part of
the fire. The perforations in the plates & may be entirely or partially closed by the
sliding doors c, e. When the fire has been made up the front of the furnace is
closed by the ordinary firing door, and the air for supporting combustion is then
supplied through the perforations in the plates d, d, and between the grate bars
from below as usual, the air so supplied keeps the fire bright and clear, and conse-
When the holes near
quently consumes the fuel in the most advantageous manner.
the firing door are closed and the others open a bright fire is kept up near the
bridge, and the smoke from the firing end is entirely consumed before it gets to the
bridge. By this means a bright clear fire can be kept up with the commonest
refuse coal, and with very little labour.
Our Invention is also applicable to the furnaces of water heating apparatus.
Having thus stated the nature of our Invention, and described a convenient
manner of performing the same, we wish to remark that we do not intend to limit
ourselves to the details given, as the number and size of the perforations through
which the air is admitted to the fire may be considerably varied, and we claim as
our Invention admitting air to the furnaces of steam boilers and water heating
apparatus through perforations in the side walls, as shewn and described.
In witness whereof, I, the said Samuel Crabtree, for myself and on behalf of
the said Thomas Crabtree and James Crabtree, have hereto set my hand and
seal, this Twenty-ninth day of July, One thousand eight hundred and
seventy-six,
SAMUEL CRABTREE. (L.S.)