IMPROVEMENTS IN MECHANICAL STOKERS
Year: 1884

page_text: I JAMES PROCTOR of Hammerton Street Iron Works Burnley in the County of
Lancaster Engineer do hereby declare the nature of my invention for IMPROVEMENTS
IN MECHANICAL STOKERS to be as follows:—
This invention relates principally to improvements in the construction of the
"mechanical stoker" for which Letters Patent were granted to me dated
November 18th A.D. 1880 N° 4759; the objects of my present invention being
to prevent the noise and shock caused by the striking or impact of the end of the
shovel lever against the buffer spring which is used for the purpose of stopping the
shovel at or about a given point as described in the Specification of the Letters
Patent above referred to, and also to regulate the feed of the coal to the said
shovels.
For this purpose according to my present invention I dispense with the buffer
springs altogether, and I utilize the tension of the shovel spring (which throws the
coal upon the fire) for the purpose of absorbing and counteracting the said impact
by fixing the said spring in such a position that the tension thereof acts in a line
with the centre of the shovel shaft, which throws on the fuel so that when the
spring is distended and released to throw on the fuel, the tension of the spring
always pulls it back into its original position in a line with the centre of the shovel
shaft; the part of the shovel lever to which the spring is attached is also inclined
in the same direction so that when the shovel is at rest this portion of the lever
and the spring are in a straight line passing through the centre of the shovel shaft
a sufficient amount of stretch being always upon the spring to hold the lever in
this position until acted upon by the gearing.
This part of my invention can be applied to other mechanical stokers of similar
construction.
As the ram in the feeding tube moves to and fro and agitates the coal, the latter
had in some cases in my former apparatus a tendency to fall too quickly of its own
weight into the shovel boxes especially if shaken at all by the action of the shovel ;
and sometimes (especially in the case of large lumps of coal being in the hopper)
the said lumps were liable to be jammed together in the tube and thus the "feed'
of the coal was consequently irregular. These defects I now remedy first by
mounting a hinged plate or flap at the top of the tube, which plate rests on the coal
"

page_text: and keeps it together and by its pressure thereon prevents it from falling too
quickly whilst at the same time it can yield and prevent the coal from becoming
jammed in the tube. I also mount the upper part of the tube on the same hinge
thereby forming a yielding lid to the tube in case the hinged plate rises against it,
and thus the coal cannot possibly become jammed fast in the tube.
By these means the noise and shock caused by the sudden impact of the shovel
levers against the buffers is entirely dispensed with and the wear and tear of the
apparatus considerably reduced and at the same time the feed of the coal is much
more regular than hitherto.

page_text: I, JAMES PROCTOR of Hammerton Street Iron Works, Burnley in the County of
Lancaster, Engineer, do hereby declare the nature of my invention for "IMPROVE-
MENTS IN MECHANICAL STOKERS" and in what manner the same is to be performed,
to be particularly described and ascertained in and by the following statement:—
This invention relates principally to improvements in the construction of the
"Mechanical Stoker," for which Letters Patent wero granted to me, dated
November, 18th A.D. 1880, No 4759.
The objects of my present invention are to prevent the noise and shock caused
by the striking or impact of the end of the shovel lever against the buffer spring,
which is used for the purpose of stopping the shovel at or about a given point as
described in the Specification of the Letters Patent above referred to, and also to
regulate the feed of the coal to the said shovels.
Such being the nature and objects of my present invention, I will now proceed
to describe in detail the manner in which the same is to be carried into practical
effect, and in order that my invention may be clearly understood, I have annexed
hereto a sheet of Drawings illustrative thereof, and have marked the same with
figures and letters of reference, corresponding with those in the following explanation
thereof.
Fig. 1 in the annexed drawing is a vertical section of the shovel box of one of
my improved "Mechanical Stokers" shewing the application of the first part of
my present improvements thereto, or that portion which relates to the shovel
springs.
According to my present invention, I dispense with the buffer springs altogether
and I utilize the tension of the shovel spring a a (which throws the coal upon the
fire) for the purpose of absorbing and counteracting the said impact, by fixing the
said spring a a in such a position that the tension thereof acts in a line with
the centre of the shovel shaft b b which throws on the fuel as drawn, so that when
the spring is distended (as indicated by the dotted lines) and released to throw on
the fuel, the tension of the spring always pulls it back into its original position in
a line with the centre of the shovel shaft bb; the part cc of the shovel lever to
which the spring is attached is also inclined in the same direction, so that when the
shovel dd is at rest, this portion of the lever cc and the spring a a are in a-
straight line passing through the centre of the shovel shaft bb a sufficient amount
of stretch being always upon the spring a a to hold the lever c c in this position,
until acted upon by the gearing.
By this means the noise and shock caused by the sudden impact of the shovel
levers c c against the buffers are entirely dispensed with, and the wear and tear of
the apparatus considerably reduced; at the same time that one spring only acts as
the shovel spring and the buffer spring also, this part of my invention can be
applied to other "mechanical stokers" of similar construction.
Fig. 2 in the annexed drawing is a front elevation (shewn partly in section) of
so much of one of my "mechanical stokers" as is necessary to shew the application
of the second part of my present improvements thereto.

page_text: This part of my invention relates to the ram box ee from which the fuel is
supplied to the shovel boxes ff-As the ram g g in the feeding tube of the box e e
moves to and fro, and agitates the coal, the latter had in some cases, in my former
apparatus, a tendency to fall too quickly of its own weight into the shovel boxes ff
especially if shaken at all by the action of the shovel dd and sometimes (especially
in the case of large lumps of coal being in the hopper) the said lumps were liable
to be jammed together in the tube, and thus the feed of the coal was consequently
irregular.
These defects I now remedy by mounting a hinged plate or flap 'g' g¹ inside the
top of the tube, which plate reste on the coal as shown, and keeps it together, and
by its pressure thereon prevents its from falling too quickly, whilst at the same
time it can yield and prevent the coal from becoming jammed in the tube-This
plan answers best for small coal, but when "cobbley" or lumpy coal is employed
I prefer to make the upper part fx fx of the tube in the form of a flap as shewn
by the dotted lines, and in some cases for mixed coals, I combine the two bringing
the flap g¹ g¹ beneath the hinged piece fx fx so that the former acts by itself for
the smaller coal, but when a large lump comes in the way, the latter yields also, so
as to allow it to pass, and thus the coal cannot possibly become jammed fast in the
tube, and the "feed" of the coal is much more regular than hitherto.
Having now particularly described the nature and object of my said inven-
tion, and in what manner the same is to be performed, I declare that what
I claim as my invention is
First, in a "mechanical stoker" of the description herein referred to, fixing the
shovel spring in a line with the centre of the shovel shaft, and at such a tension,
that it acts both as a shovel spring and a buffer spring substantially as hereinbefore
described, and
Secondly, hingeing the top of the tube or a plate hung therefrom, or both, so as
to bear upon the coal, and prevent it from falling too rapidly and at the same
time to admit of its yielding or giving way when required to allow cobs or lumps
to pass.