Improvements in Furnace Smoke Preventers
Year: 1891

page_text: Date of Application, 6th Aug., 1891
Complete Specification Left, 4th May, 1892-Accepted, 4th June, 1892
PROVISIONAL SPECIFICATION.
Improvements in Furnace Smoke Preventers.
WALLACE MCGUFFIN GREAVES Engineer 6 Fountain Street Manchester. I
do hereby declare the nature of this invention to be as follows:--
In the front of the furnace and above the door I make an opening, large enough
to admit a two inch steam pipe, bend or elbow, or other suitable size or form of
hollow conductor having secured the same-I now take a small steam pipe, coupling
one end to the boiler, or other direct supply of live steam, and the other end into
the above mentioned cup, bend or elbow, loosley leaving a small open space all
round it, by which means air can pass. This small steam pipe must have a
stop tap, to be opened before beginning work and shut off at the finish of the days
work; but on the front of the boiler and just over the fire door a second tap must
be inserted, this second tap must be so made that it never becomes completely
closed, but at all times allows a slight escape of steam enough to ensure its acting
as a slight injector of air by the free space left in the first mentioned bend or elbow,
by reason of the difference between the small steam pipe and the aforesaid bend or
elbow. This imperfect tap should for preference be a plug-tap and be worked by
a box key made with a long handle reaching a point just above the fire-door.
Upon the fire-door and next to it's hinge I fasten a bracket which reaches to a
point a little higher than the level of the key just before-mentioned, upon the top of
this bracket I have a small arm attached at right angles so that when the fire-door
At the end of this arm
is closed the arm points in a direct line with the door.
I couple a small chain and attach the other end of the chain to the before mentioned
key-It's object or use being "that when the door is opened the small arm turns
outwards from the boiler and turning upon it's centre pulls the chain after it and
thereby opening the tap and allowing the free escape of steam and so increasing
the power of the injector.
Upon closing the fire-door the chain permits the key to drop back to it's original
position.
I claim the second tap imperfect bracket on fire-door and chain coupling to tap
handle and bracket.
COMPLETE SPECIFICATION.
Improvements in Furnace Smoke Preventers.
WALLACE MGUFFIN GREAVES Engineer, 6ª Fountain Street, Manchester,
do hereby declare the nature of this invention and in what manner the same is to
be performed, to be particularly described and ascertained in and by the following
statement :-
My invention is essentially a contrivance for automatically increasing or decreasing
a current of air and steam injected into a furnace on the opening and shutting of
the furnace door.
Fig. 1. shows the front of a boiler and furnace.
Fig. 2. shows a transverse section through tap L on an enlarged scale.
The pipe C communicates with boiler at A. B is tap worked by hand to close
and open current in pipe C as desired. D is union. Lis tap which is made and
fitted so as never to be entirely closed. In preference it is a plug tap with plug F.
J is cup into which the steam pipe C enters. An opening is there made into the

page_text: furnace. Air enters the cup as shown by arrows drawn in by the steam current in
pipe C.
To the furnace door is attached a bracket H. To this bracket is attached
à chain G. The other end of chain is attached to key E of tap L. The key does
not fit closely to plug F as shown in Fig. 2. Some movement of the key takes
place before tap is moved.
When the furnace door is open the key E is moved so as to open the tap and so
increases the power of the injector. When the door is closed the key E drops by
its own weight and partially closes the tap L.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is.
A contrivance for automatically increasing and diminishing an injecting current
into a furnace on the opening and shutting of the furnace door by means of a
coupling attached at one end to a bracket in the furnace door and at the other end
to the handle of an imperfect tap on the steam pipe substantially as described and
shown.
Dated this 2nd day of Max 1000
W. H. MUNNS,
Agent for Applicant.