Improvements in Smoke Consuming Apparatus for Steam Boiler and other Furnaces.
Year: 1897

page_text: PROVISIONAL SPECIFICATION.
Improvements in Smoke Consuming Apparatus for Steam Boiler
and other Furnaces.
We, JOSEPH DUGDALE, Junior, of Soho Foundry, Blackburn, in the County of
Lancaster, Machine Maker, and JOHN FROST DAVIES, of the same address,
Engineer, do hereby declare the nature of this invention to be as follows:-
Our invention relates to improvements in smoke consuming apparatus for
steam boiler and other furnaces and the objects of our improvements are to
close the furnace door automatically and to admit air at the door, at or beyond
the bridge, or between the door and bridge, when the furnace door is opened, and
to shut the air off automatically by the motion which closes the door.
In applying our improvements to a furnace fitted with a mechanical stoker
we employ a handle secured to a stud carried preferably by the framing of the
door and to this stud we secure a finger which projects into the door frame and
supports the door. To the handle we also secure a pin on which is pivoted a
catch controlled by the fireman and weighted at its other end which at certain
times engages with a recess in an inclined or cam surface on the back or boss of
a ratchet wheel or segment of a wheel, which is mounted on a stud and turned
by a nawl with a boss fitted loosely upon the eccentric boss of a worm wheel
driven from a worm mounted upon the rotating shaft of the mechanical stoker,
or otherwise suitably actuated.
An adjustable segmental plate is mounted loosely on the stud which carries
the ratchet wheel, the plate being shaped to hold the pawl out of gear with the
teeth or to gear with them at regulated times, and a slotted arm on this plate
is connected by a rod to the handle.
When the handle and catch have been moved to open the door if it be desired
to partially close the door immediately the coal has been fed on to the furnace
the fireman releases the handle and the pivoted catch and the adjustable plate
being set for this purpose, holds the pawl out of gear with the ratchet wheel, and
thus the door is free to move at once say to a half closed position in which it
is held by the weighted end of the pivoted catch being caught in the recess in
the cam surface at the back of the ratchet-wheel. When the handle is in. this
second position the plate is held so that the pawl will be in gear with the ratchet
wheel and will gradually turn it thereby releasing the catch from its recess and
gradually closing the door.
If it be desired to bring the automatic closing motion into gear immediately
the fireman has opened the door and let go the handle the adjustable plate will
be shaped or adjusted accordingly to allow the pawl to engage with the teeth on
the ratchet wheel so that the latter will be slowly turned and the door gradually
closed.
The mechanism may be so arranged that after the door has been opened it can
only be closed by the automatic arrangement.
The apparatus, with slight modifications, can be applied to hand fed furnaces
fitted with horizontal or vertical hinged or pivoted doors.
Immediately the door is quite closed the pawl is moved out of gear with the

page_text: ratchet wheel by the shape of the segmental plate and the parts re-set them-
selves automatically.
We propose also if desired to connect the handle by rods to a damper (or
dampers) covering an opening (or openings) in the bridge at the back end of
the furnace or at any other suitable place so that the damper is opened and
closed automatically and simultaneously, or otherwise, with the furnace door.
We wish it to be understood that we do not limit ourselves to any particular
arrangement of mechanism as any other suitable arrangement may be employed
for automatically opening and closing the furnace door as herein described.
Dated this 16th day of December 1897.
H. B. BARLOW & GILLETT,
Agents for Applicants.
Improvements in Smoke Consuming Apparatus for Steam Boiler
and other Furnaces.
We, JOSEPH DUGDALE, Junior, of Soho Foundry, Blackburn, in the County of
Lancaster, Machine Maker, and JOHN FROST DAVIES, of the same address,
Engineer, 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:-
Our invention relates to improvements in smoke consuming apparatus for
steam boiler and other furnaces and the objects of our improvements are to
close the furnace door automatically and to admit air at the door, at or beyond
the bridge, or between the door and bridge, when the furnace door is opened, and
to shut the air off automatically by the motion which closes the door.
In the accompanying four sheets of drawings-
Fig. 1 is a front elevation of part of the framing of a furnace door adapted
for a mechanical stoker and fitted with our improved apparatus for closing the
furnace door automatically, Fig. 2 is a plan of part of Fig. 1, and Fig. 3 is a
sectional side view of Fig. 1, Figs. 1 and 3 are similar views to Figs. 1
and 3 respectively but showing the furnace door partly closed instead of full
open, Figs. 4, 5 and 6 are detail views showing the segmental plate and pawl in
three different positions, Figs. 7 and 8 are front view and plan respectively of
a hinged furnace door to which our improved closing motion is applied, Fig. 9
is a detail view of part of the same, Figs. 10 and 11 are two views of an arrange-
ment for closing the openings in a furnace door automatically when the door
is shut, and Fig. 12 is a longitudinal section of a furnace flue illustrating the
mode of connecting the door closing mechanism to a damper at the bridge.
In Figs. 1, 2 and 3,-2 denotes the framing of the furnace door, 3 the door, 4 a
stud carried by the framing, and 5 a handle and 6 a finger, both secured to the
stud 4, the finger 6 projecting into the door frame and supporting the door 3.
To the handle we also secure a pin 7 on which is pivoted a finger catch 8 con-
trolled by the fireman and weighted at its other end 9 which at certain times
engages with either of two inclined flanges or cam projections 10 on the back
or boss of a ratchet wheel or toothed segment 11, and by which means the door
is latched either full open as in Figs. 1, 2 and 3, or partly open, as in Figs. 1^
and 34. The toothed segment 11 is mounted upon a stud 12 and is turned by
a pawl 13, the boss of which is mounted loosely upon the eccentric boss 14 of
સ worm wheel 15 driven by a worm 17 from a rotating shaft 16 which is
employed to drive the mechanical stoker. An adjustable segmental plate 18 is
mounted loosely upon the stud 12 and this plate is shaped to hold the pawl 13
out of gear with the teeth on the segment 11 or allow it to gear with them when

page_text: the door is to be closed by the automatic mechanism; a slotted arm
on the
plate 18 is connected by an adjustable rod 19 to the pin 7 secured to the handle 5
for the purpose of regulating the position of the plate 18 on the stud 12. To
regulate the position of the toothed segment 11 we employ an adjustable stop
plate 20 bolted to the door frame 2 against which the segment 11 normally rests.
To open the door 3 to the fullest extent, as shown in Figs: 1, 2 and 3, the
handle 5 is actuated and the finger catch 8 falls into the space below the lower
or inner cam projection 10 and so holds the door full open. If it be desired to
partially close the door immediately the coal has been fed on to the furnace,
the fireman releases the handle 5 and the pivoted catch S from under the inner
cam projection 10 (and the plate 18 being set for this purpose, at the moment
holds the pawl 13 out of gear, see Fig. 4, with the toothed segment 11) and
lowers the door 3 at once, say to a half closed position, as shown in Figs. 1 and 3,
in which it is held by the catch being latched below the upper or outer cam
projection 10. When the handle is held in this second position the cut away
portion of the plate 18 has been moved into a position, shown in Figs. 1 and 5,
and is held by the connection 19 from the handle 5 SO as to allow the
pawl 13 to gear into the teeth of the segment 11 which with the cam projection 10
will be slowly turned by the pawl as it is actuated by the rotation of the shaft 16.
The effect of this rotation is to cause the end 9 of the catch S to travel away
from the centre 12 as the inclined cam projection 10 is moving under it and this
allows the door 3 to gradually close by its own weight, until by the continued
rotation of the segment 11 the cam projection 10 has been moved past the end
of the catch 8 which is thereby released and the door being free at once falls
the remaining distance and closes completely, and simultaneously by the con-
nection 19 the segmental plate 18 is moved into the position shown in Fig. 6.
If it be desired to bring the automatic closing motion into gear immediately
the fireman has opened the door and let go the handle 5 the plate 18 will be
shaped or adjusted accordingly to allow the pawl 13 to engage with the teeth
on the segment 11 while the catch end 9 engages in the lower or inner cam
projection 10 while the latter will be slowly turned and the door closed as
already described; or the mechanism may be so arranged that after the door has
been opened it can only be closed by the automatic arrangement.
Figs. 7, 8 and 9 represent substantially the same mechanism as Figs. 1, 2
and 3, with the slight alterations necessary to adapt our invention to a hinged
door opening and closing approximately horizontally.
In these views, the door has an inclined surface under its upper bearing
which tends always to close it.
The shaft 16, in this case a special shaft for the purpose of our invention,
worm 17, worm wheel 15 and pawl 13, mounted loosely on the eccentric boss 14
of the wheel 15, give motion to the toothed segment 11, as previously described;
but an additional pawl 21 is employed as a retaining catch to prevent the seg-
ment moving backward, and the toothed segment 11 has an adjustable stud 22
screwed into it, which when the segment is actuated, comes in contact with an
adjustable stud 23 connecting an arm 24 pivoted on the stud 12 to the light end
of the segmental plate 18. Consequently when the stud 23 is depressed it also
carries down with it the segmental plate 18 and the arm 24.
When the door is closed, as in Fig. 7, the arm 24 is latched under, it but when
opened by hand the arm 24 rises by the weight of the connected parts and
latches the door open as indicated in Fig. 9. When the shaft 16 is set in motion
and the pawl 13 actuates the toothed segment 11 the raised end of the arm 24
is gradually depressed until the door 3 is released, and is then closed by the
inclined surface above specified. When the door is again opened and the arm 24
rises into the position shown in Fig. 9 the parts re-set themselves automatically.
that already
Figs. 10 and 11 illustrate a very similar arrangement to
described but in this case the door 3 swings in a horizontal plane and is opened
and closed by hand and the motion imparted by the pawl 13 to the toothed seg-

page_text: ment 11 is utilised to gradually close (after the door 3 has been shut) a rotary or
sliding damper 25 fitted over openings 26 formed in the door. To effect this the
damper 25 has teeth formed on its periphery and these teeth are in gear with
teeth on a rack 27 supported and free to slide on the door 3. The sliding rack 27
has a projection 28 secured to it and as the shaft 16 rotates and the pawl 13
actuates the toothed segment 11 a projection 29 on the latter comes in contact
with the projection 28 and so moves the rack 27 forward thereby slowly turning
the rotary damper 25 and gradually closing the openings 26 in the door.
Whilst the rack 27 is being gradually moved forward to close the damper an
inclined surface on the underside of the rack travels over and gradually depresses
an arm 30 carried by the segmental plate 18 and by the time that the rack has
moved far enough to close the openings 26 the segmental plate 18 will have
moved far enough to disengage the pawl 13 and also the retaining catch 21.
When the door is again opened a lever 31 fulcrumed thereon is pressed out-
ward by a stationary incline 32 fixed to the framing and coming into contact
with the end of the sliding rack 27 presses it back and allows the parts to re-set
themselves automatically.
Fig. 12 illustrates an arrangement for simultaneously opening the dampers
by the connections from the handle 5 by which the door is opened. In this
arrangement we fix an arm 33 on the pivot 4 which moves with the handle 5
and connect this arm 33 by a rod 34 to an elbow lever 35 which is connected by
a rod 36 to two levers 37 and 38 which respectively control the movements of
the two dampers 39 and 40. When the door 3 is opened by the movement of
the handle the dampers 39 and 40 are simultaneously opened the former un-
covering openings near the front of the furnace and the latter uncovering air
passages near the bridge 41. In like manner the dampers are closed when the
movement is reversed and the door 3 is shut.
We wish it to be understood that we do not limit ouselves to any particular
arrangement of mechanism as any suitable arrangements other than those illus-
trated may be employed for opening and automatically closing the dampers or
the furnace door as herein described.
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed we declare that what
we claim is:-
1. The arrangement, use and application of mechanism for automatically
closing a furnace door substantially as herein set forth.
2. The arrangement, use and application of mechanism to close a furnace door
automatically and to admit air at the door, at or beyond the bridge, or between
the door and the bridge, when the furnace door is opened, and to shut off the air
automatically by the motion which closes the door substantially as herein set
forth.
3. The arrangement, use and application of automatic mechanism for
gradually shutting off the supply of air after the furnace door has been closed
by hand substantially as herein set forth.
4. The several combinations and arrangements of mechanism for automatically
closing the furnace door or shutting off the air or both substantially as herein
described and as illustrated by the accompanying drawings.
T1
111
1000
H. B. BARLOW & GILLETT,
Agents for Applicants, 17, St. Ann's Square, Manchester.