IMPROVEMENTS IN THE REGISTERS OF STEAM BOILERS
Year: 1876

page_text: LETTERS PATENT to James Ledger, Engineer and Patent Agont, of 61, Fleet
Street, London, for the Invention of "IMPROVEMENTS IN THE REGISTERS OF
STEAM BOILERS." A communication from abroad by Louis Eugène Nouflard,
of Lille, in the French Republic.
Sealed the 9th February 1877, and dated the 17th August 1876.
PROVISIONAL SPECIFICATION left by the said James Ledger at the Office of
the Commissioners of Patents on the 17th August 1876.
JAMES LEDGER, Engineer and Patent Agent, of 61, Fleet Street, London. "Iы-
PROVEMENTS IN THE REGISTERS OF STEAM BOILERS." A communication from abroad
by Louis Eugène Nouflard, of Lille, in the French Republic.
This Invention relates to certain improvements in the registers of steam boilers,
whereby the said registers, will be closed, or partially closed automatically during
the time that the fuel is introduced in the furnace, thereby preventing a current of
cold air entering when the furnace door is opened.
The following is the manner I propose to attain the above object :-At any
suitable distance from the boiler I place a cam or excentric making one revolution
in ten minutes, or thereabouts. This cam acts on a slide to which is attached a
chain, the end of which is fixed to a lever. Another chain goes from the said lever
to the register.
The operation of the above arrangement is as follows:- -When the stoker
introduces fresh fuel in the furnace the register is nearly closed for about two
minutes, owing to the action of the cam on the slide and lever aforesaid, thus
preventing a current of air entering during that operation. The cam continuing
its action opens the register in full for the next two minutes, and then gradually
closes it during the following six minutes. One minute before the expiration of
the time the slide aforesaid acts on a bell to warn the stoker that the furnace is
ready for another charge of fuel.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said James Ledger in the Great Seal Patent Office on the 10th February
1877.
"Iar-
JAMES LEDGER, Engineer and Patent Agent, of 61, Fleet Street, London.
PROVEMENTS IN THE REGISTERS OF STEAM BOILERS." A communication from abroad
by Louis Eugène Nouflard, of Lille, in the French Republic.
This Invention relates to certain improvements in the registers or dampers of
steam boilers, whereby the said registers will be automatically closed, or partially
closed, during the time that the fuel is introduced in the furnace, thereby preventing
a current of cold air entering when the furnace door is opened.
:-
The following is the manner by which I propose to attain the above object:-
At any suitable distance from the boiler I place a cam or excentric making one
revolution in twelve minutes, or thereabouts. This cam acts on a slide to which is
attached a chain, the end of which is fixed to a lever. Another chain goes from the
aid lever to the register or damper.
The operation of the above arrangement is as follows:-When stoker introduces
fresh fuel in the furnace the register is nearly closed for about thirty seconds, owing
to the action of the cam on the slide aforesaid, thus preventing a current of air
entering during that operation. The cam continuing its action opens the register
in full during the next two minutes, and then keeps it open for five minutes,
after which it gradually closes it during the following four and a half minutes. One
minute before the expiration of the time, the slide aforesaid acts on a bell to warn
the stoker that the furnace is ready for another charge of fuel.
And, in order to explain this Invention more fully, I will now proceed to describe
the means whereby it may be put into practical effect, reference being had to the
illustrative Sheet of Drawing accompanying these presents, and to the numeral figures
and letters of reference marked thereon respectively as follows:
DESCRIPTION OF THE DRAWING.
Figure 1 is an elevation, and Figure 2 a plan of the improvements in registers or
dampers of steam boilers as applied to two boilers, and constructed according to this
Invention.
In each of these Figures similar letters of reference are used to denote cor-
responding parts.
A is a frame, in which work the two slides B, B¹, put in motion by cams C, C¹,
working againsts rollers D, D¹. The slides B, B1, are united by chains b, b¹, to levers
E, E, which are also connected to the dampers F, F, by chains f, f¹, which are
made to pass over pulleys G, G₁. The weight of the registers or dampers is counter-
balanced by weights H, H¹, connected to the said dampers or registers by chains
h, h', passing over pulleys K, K¹.
To regulate the opening of the flues L, L', screws M, M³, are used as shown at
the lever E, or by eyelets m, placed at a certain distancef rom each other along the
lever E¹. Motion is given to the cams C, C, by a worm wheel N and worm O,
receiving notion from another worm wheel P, and worm Q, on the spindle of which
is a pulley R actuated by any suitable driving power.
MODE OF OPERATION.
The speed of the cams being regulated to one revolution in twelve minutes, the
result of their outline on the dampers F, F, by the slides B, B¹, levers E, E¹, chains
b, b', and ff, will be to raise or lower the said dampers or registers in the following
mauner: During the thirty seconds in which the stoker is feeding the furnace of
the boilers the dampers will be closed, or nearly so, in order to prevent any influx
of cold air under the said boilers. During the next two minutes the dampers aro
opened in full, and remain opened for five minutes. Then during four and a half
minutes they are gradually closing, so as to keep the heat inside the furnace.

page_text: The stoker's attention is called by a bell S striking ono minuto before the
expiration of the last four and a half minutes, which gives him ample time to get
ready for another charge, as the damper or register remains almost closed for thirty
seconds.
The object of the regulating screws M, M¹, or eyelets m, is to give more or
less opening to the flues L, L, according to circumstances or to the quality of fuel
used.
Having now described and set forth the nature and object of this Invention, as
communicated to me from abroad, I would remark in conclusion that I do not limit
or confine myself to the precise details and form of apparatus above described and
represented, as these may vary according to circumstances; but what I claim as my
Invention, and desire to secure by the horein-before in part recited Letters patent,
is, "closing and opening the flues of steam boilers by means of dampers or registers
worked automatically, substantially as described and represented."
I witness whereof, I, the said James Ledger, have hereunto set my hand
and seal, this Eighth day of February, in the year of our Lord One thousand
eight hundred and seventy-seven.