Improvements in and connected with Fire Doors for Locomotive Boiler and other Furnaces.
Year: 1891

page_text: Date of Application, 25th May, 1891
Complete Specification Lelt, 24th Feb., 1892-Accepted, 9th Apr., 1892
PROVISIONAL SPECIFICATION.
Improvements in and connected with Fire Doors for Locomotive
Boiler and other Furnaces.
I, JAMES JOHNSON of 112 Leslie Terrace, Aberdeen, in the County of
Aberdeenshire, Scotland, Locomotive Engineer, do hereby declare the nature of
this invention to be as follows:-
:-
This invention has reference to improvements in and connected with fire doors
for locomotive boiler and other furnaces.
I provide a furnace door comprising two parts or flaps (hereinafter called for
distinction respectively the upper door and the lower door); these are arranged to
open outward and away from one another and are capable of being closed air
tight or practically so. The upper door serves for the regulation of the draught;
the lower door for the purpose of charging the fuel.
For directing the air current, a baffle plate is provided which I arrange to be
capable of adjustment as will hereafter more clearly appear.
The upper door is furnished at one edge with a projection that passes through a
slot in a cheek fixed at the side of the door and when the upper door is opened
engages with a curved rack pivoted to the said cheek thereby holding the said
door open. The pivoted rack is provided with a handle whereby it can be drawn
back out of engagement with the projection when desired to close the door.
The lower door has fixed to its hinge-bolt or pivot a crank arm having a pin
working freely in a slot in the lower extremity of a link which, at its other
extremity, is connected to the short arm of a bell crank operating lever working
on a rotary stud or spindle to which the battle plate is rigidly secured.
The lower door is held in its closed position by a latch secured to door frame
and engaging with a corresponding projection or engagement piece on the lower
door. The parts are so arranged that when this latch is disengaged, as for.
instance by a knock with the shovel, the lower door will, by its own weight and the
weight of the levers connected therewith and made to slightly overbalance the
weight of the baffle plate be caused to fall open thereby causing the baffle plate to
swing up into its highest position so as to be out of the way for firing, the lower
door itself falling upon an india rubber or other suitable stop or cushion and the
pin of the crank being at the lower end of the slot in the before mentioned link
connected with the operating lever. The lower door can thus be closed by raising
the said lever and the baffle plate can then be adjusted by moving the lever
backward again, the door being held fast by its latch and movement of the lever
being permitted by the slot in the link connected therewith. The operating
lever carries a suitable spring catch lever or fixing-lever working on a curved rack
or toothed quadrant, for securing the lever in any desired position. The battle
plate is secured to the spindle or axle or to a frame connected thereto, by bolts
and nuts so that should a plate be destroyed another can readily be substituted
therefor.
Dated thish dow of M., 1901
W. LLOYD WISE,
Per F. J. Brougham,
46, Lincoln's Inn Fields, London, W.C., Agent for the Applicant.

page_text: COMPLETE SPECIFICATION.
Improvements in and connected with Fire Doors for Locomotive
Boiler and other Furnaces.
I, JAMES JOHNSON of 112 Leslie Terrace, Aberdeen, in the County of
Aberdeen, Scotland, Locomotive 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 :-
This invention has reference to improvements in and connected with fire doors
for locomotive boiler and other furnaces.
I provide a furnace door comprising two parts or flaps (hereinafter called for
distinction respectively the upper door and the lower door); these are arranged to
open outward and away from one another and are capable of being closed air
tight or practically so. The upper door serves for the regulation of the draught;
the lower door for the purpose of charging the fuel.
For directing the air current, a baffle plate is provided which
capable of adjustment as will hereafter more clearly appear.
In the accompanying drawings,
Fig. 1 is a front elevation,
Fig. 2 a side elevation and
arrange to be
Fig. 3 a detail view of a locomotive fire door in two parts with baffle plate and
gear, constructed according to this invention.
A is the upper door for regulating the draught. B is the lower door for charging
the fuel. C is the adjustable battle plate. D is a curved rack for holding the
upper door A open. E is a bell crank operating lever for working the door B and
for adjusting the battle plate C. F is a latch for holding the door B in its closed
position, and G is a stop or buffer for the said door.
The upper door A is furnished at one edge with a projection A' that passes
through a slot in a check A² fixed at the side of the door, and, when the upper
door is opened, engages with the curved rack D which is pivoted at D' to the said
check thereby holding the door A. open. The pivoted rack D is provided with a
handle D whereby it can be drawn back out of engagement with the projection
when desired, to close the door.
The lower door B has fixed to its hinge-bolt or pivot B' a crank arm B² having
a pin working freely in a slot E' in the lower extremity of a link E which, at its
other extremity, is connected to the short arm of the bell crank operating lever E
fixed upon a pivot, shaft, or spindle C to which the baffle plate C is rigidly
secured.
The lower door B is held in its closed position by a latch F which may have
more than one notch as indicated in dotted lines secured to the door frame A*
and engaging with a corresponding projection or engagement piece B³ on the
lower door. The parts are so arranged that when this latch is disengaged, as for
instance by a knock with the shovel, the lower door B will, by its own weight
and the weight of the levers connected therewith overbalance the battle plate and
fall open thereby causing the baffle plate to swing up into its highest position so
as to be out of the way for firing. The lower door itself is arrested by the stop
or cushion G provided with india rubber springs G', the pin of the crank B2 when
the door B rests on the said stop being at the lower end of the slot E in the
before mentioned link. The lower door can thus be closed by raising the said
lever, and the baffle plate C can then be adjusted by moving the lever backward
again, the door being held fast by its latch F and movement of the lever being
permitted by the slot E' in the link E. The operating lever E carries a suitable
spring catch lever or fixing-lever H working on a curved rack or toothed
quadrant, this catch lever when released permitting the lever E to move in one
direction, but engaging with the teeth of the rack I when it tends to move in

page_text: the other direction, so securing the lever and the baffle plate in position. The
baffle plate is secured to the spindle C¹ or to a frame connected thereto, by belts
and nuts C so that should a plate be destroyed another can readily be substituted
therefor.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. For a locomotive boiler or other furnace, the arrangement of an upper and a
lower fire door such as A and B with baffle plate, the lower door and battle plate
being under control of one lever substantially as described.
2. The combination and arrangement of parts substantially as described and
shown in the drawings for the purpose specified.
Dated this 24th day of February 1892.
W. Lloyd Wise,
JAMES JOHNSON.
46, Lincoln's Inn Fields, London, W.C., Agent for the Applicant.