Improved Mechanical Stoker.
Year: 1891

page_text: The decision of the Comptroller-General, of the 26th day of June 1893, allowed,
under Section 18 of the Patents, &c. Act, 1883, an Amendment of this
Specification.
Date of Application, 12th Sept., 1891-4ccepted, 17th Oct., 1891
COMPLETE SPECIFICATION (AMENDED).
Improved Mechanical Stoker.
I, RICHARD HARLEY Williamson of 21 Victoria Street, Ashton-under-Lyne,
in the County of Lancaster, Joiner, 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 said invention relates to an improved apparatus for automatically supplying
coal to the furnaces of steam boilers.
The accompanying drawing which is partly in section illustrates the construction
of the said apparatus and its application to one of the furnaces of an ordinary'
Cornish boiler.
a is the coal bunker or hopper. Immediately thereunder is a shoot or spout b
preferably of sheet iron. At 6 the shoot is attached to a convenient fixed support.
The mode of attachment may be by means of a hinge but I prefer to form this
part of the shoot of comparatively thin sheet iron, and to bolt or rivet it to the
fixed support. An elastic or yielding joint is thus obtained which permits the
shoot to vibrate up and down. c is a cam on which the under surface of the shoot
rests in such a manner that as the cam c rotates the shoot will be struck by
the leaves of the cam and be caused to vibrate and the coal-which-falls from the
hopper into the shoot will be shaken out on to the Archimedian screw d. By the
rotation of the latter the coal is carried upwards along the tube d³ into the box e
and forced through the aperture & therein into the furnace where it will spread
itself out amongst the burning fuel.
The apparatus is intended to work continuously and in order to regulate the
gradual supply of fuel to correspond to the rate of combustion in the furnace I
provide a rod attached by a flexible connection such as a chain at f¹ to the
shoot b. The upper end of the rod fis screwed and passes through a nut in the
boss of the hand wheel f". By turning the hand wheel the shoot 6 may be
raised so as only to just touch the leaves of the came when the vibration will be
very slight and very little coal will be shaken out or it may be lowered so far that
each blow of the leaves of the cam will impart considerable vibration to the shoot
and hence more coal will be discharged on to the screw d. At the place of contact
between the under side of the shoot 6 and the cam c detachable plates may be
provided which may be readily replaced when worn out by the action of the cam c.
For actuating the apparatus I prefer to use the gearing indicated chiefly by
dotted lines in the drawing, namely,-A pulley driven by a cord or belt & imparts
rotary motion to the spur wheel mounted on the same shaft. Into the spur
wheel is geared the spur wheel which drives the shaft o on which the cam c
is mounted. From the spur wheel on the cam shaft c is driven the spur
wheel keyed on the same shaft as the bevel wheel which in turn drives the
bevel wheel. The latter is secured to the shaft d of the Archimedian screw d.
The whole of the gearing is mounted in a suitable frame work m.

page_text: In order to close the aperture and thus prevent ingress of air during a
temporary stoppage as for instance at meal times the bottom of the box & is
hinged at and by depressing the handle (pivoted at e) the bottom ³ may be
raised. A bolt catch or other similar device is provided for keeping down the
handle e' as will be well understood without further description.
The gradual and continuous supply of coal to the furnace and its distribution
amongst the burning fuel by the hereinbefore described apparatus without the
necessity of opening the furnace doors is attended by as diminished consumption
of fuel and at the same time the production of smoke is almost entirely prevented.
The details of the apparatus and the relative proportions and arrangements of
the parts thereof may be varied to suit different types of boilers and local
circumstances without. departing from its characteristic. features. To protect the
part of the apparatus in the furnace from the action of the heat firebricks may be
inserted in suitable recesses: as shown at eº..
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―
1. A mechanical stoker consisting essentially of an Archimedian screw working
in a tube for conveying the coal into the furnace: and in combination with an
adjustable vibrating, shoot for shaking out the coal into the conveying tube
substantially as hereinbefore described.
2. In a mechanical stoker as set forth in Claim No. I the box e at the end of the
conveying tube, provided with a hinged bottom for closing the entrance to the
furnace during temporary stoppage.
3. In a mechanical steker the use of an Archimedian-screw rotating in a tube
disembeguing beneath the burning fuel substantially as and for the purpose herein-
before set forth,
Dated this Eleventh day of September 1891.
EDWARD TURNER WHITELOW,
70, Deansgate, Manchester, Agent for the Applicant.