CERTAIN IMPROVEMENTS IN WEIGHING MACHINES
Year: 1847

page_text: POOLEY'S SPECIFICATION.
TO ALL TO WHOM THESE PRESENTS SHALL COME I HENRY
POOLEY, of Liverpool, in the County of Lancaster, Ironfounder, send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Royal Letters Patent under the Great Seal of the United Kingdom of Great
Britain and Ireland, bearing date at Westminster, the Sixteenth day of June,
One thousand eight hundred and forty-seven, in the tenth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
Henry Pooley, my exors, admors, and assigns, Her especial licence, full power,
sole privilege and authority, that I, the said Henry Pooley, my exors, admors,
and assigns, or such others' as I 'the said Henry Pooley, my exors, admors, or
assigns, should at any time agree with, and no others, from time to time and
at all times during the term of years therein expressed, should and lawfully
might make, use, exercise, and' vend, within England, Wales, and the Town
of Berwick-upon-Tweed, in the Islands of Guernsey, Jersey, Alderney, Sark,
and Man, and in all Her said Majesty's Colonies and Plantations abroad,
Invention of "CERTAIN IMPROVEMENTS IN WEIGHING MACHINES;" in which
said Letters Patent is contained a proviso, that I, the said Henry Pooley, shall
cause a particular description of the nature of my said Invention, and in what
manner the same is to performed, by an instrument in writing under my hantl
and seal, to be inrolled in Her said Majesty's High Court of Chancery within
six. calendar months. next and immediately after the date of the said in part
my

page_text: recited Letters Patent, as in and by the same, reference being thereunto had,
will more fully and at large appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
Henry Pooley, hereby declare that my said Invention has relation to that
"description of weighing machines which are constructed on what is known as
the steel-yard principle, and has for its object first, to render the same more
exact of performance; second, to protect certain of the parts thereof from
accidental or designed derangement; third, to relieve more speedily and
effectually the knife edged bearings of the larger weighing machines of the
class, commonly called weighbridges, from strain or wear during the placement
of ponderous goods upon the platforms, or the passing of carts or railway
trains over the same; fourth, to combine weighing machines of the improved
construction last-mentioned with turntables upon railways; fifth, to protect
the pits formed for the reception of such weighing machines from the intrusion
of wet and dirt; sixth, to adapt platform weighing machines to the purpose
of regulating the proportional impact of each wheel of a locomotive engine
upon the rails of railways; and seventh, to adapt lifting or hoisting cranes
to weighing purposes by the combination therewith of a steelyard and single
lever, and to relieve the knife edged centres of such cranes from wear, except
when in the act of weighing. And I declare that the manner in which the
said Invention is to be performed is as follows, reference being had to the
Drawings hereunto annexed, that is to say:―
Figure 1, Sheet No. 1, of the Drawings annexed, represents a top plan of
one of my improved weighing machines of the larger kind, with the table or
platform removed in order to shew the construction of the levers and other
parts beneath. Figure 8 is a side elevation of the same; and Figure 4 a
transverse elevation. In the two last views, several of the parts are shewn in
section. A, A, are two foundation plates of cast iron securely bolted to a level
bed of stone, brick, or timber; a top view of one of these foundation plates is
given separately in Figure 2. B, B, B¹, B', are four props or fulcra, which rest
loosely in slots or sockets c, c, made for them in the foundation plates, and
have a small extent of lateral action to admit of their accommodating them-
.selves to the movements of the principal levers. These fulcra have steel faces
on their upper ends, which in their cross section are of a curved form, upon
which faces the knife edges (F, F) of the levers rest; D 1, and D 2, are the
two principal levers of the machine, the larger one D1 stretches in a diagonal
direction from its fulcra (B, B) to the point E, where it is connected with the
steelyard (Figures 1 and 4). F, F, are the knife edges by which this lever
rests on the fulcra B, B. The shorter lever D³ rests by knife edges F, F, on

page_text: the fulcra B', B'; at its smaller end it terminates in a knife edge (seen in
section, Figure 3) which rests within a coupling ring L, by which ring it is
connected to the principal lever D¹ at a projecting point cast thereon. G, G,
G, G, are four verges or knife edged supports, which are inserted in the top..
surfaces of the levers D', D', and support the table or platform of the machine..
M is a bar of timber cut to the form shewn, and bolted to the underside of
the long lever D¹, for the purpose of correcting the vibration which would
otherwise be caused in the machine by the drawing of a carriage on to the
platform, and which is at present a source of much inaccuracy in weighing.
machines. N (Figure 3 and 4). are two strong beams of timber (or made of..
iron and timber combined, if preferred) for the purpose of sustaining the:
weight of the platform and load. To the underside of these beams are bolted
four bearing pieces o, o, o, o, of cast iron, from which project downwards four:
studs 9, 9, 9, 9, with curved steel faces, which rest on the knife edged verges G.:.
These bearing pieces are prolonged outwards beyond the studs to the extremi-
ties of the beams. P, P, are cast iron receiving props that are firmly bolted'
or otherwise secured to the foundation plates A, A, and come immediately
under the prolonged portions of the bearing pieces o, o.
When the machine
is in a dormant or quiescent state, that is to say, ungeared or not in a weighing
state, the platform rests on these props; a plan of one of these props is given
separately in Figure 5, a side view Figure 6, and a front view in Figure 7...
The balance or steelyard part of the machine, with the framework to which it
is attached, forms the upper portion of the side elevation, Figure 3. Q is the.
steelyard which is constructed and suspended as herein-after described; R, the
moveable poise with its hanger, which indicates the fractional parts of a ton
or hundredweight, as the case may be; S, the counterpoise by which the.
levers, platform, and other parts of the machine are balanced, and upon the
plate of which weights representing tons or hundredweights, as the case may be,
are placed in weighing (except in those machines which have a supplementary
steelyard, as herein-after described. The steelyard is shewn detached from its..
frame, and on an enlarged scale, in Figure 8 to 13, both inclusive, Figure 8
being a side elevation of it; Figure 9, a longitudinal vertical section; Figure..
10, a horizontal section; Figure 11, a top view of it; and Figures 12 and 13,
transverse sections on the lines a, b, and c, d. It will be seen from an inspec-
tion of these Figures that the body of the steelyard is hollow, and has con-:
cealed within it an adjusting weight or bar T, which is moveable to and fro in
its recess by means of a screwed rod U. The screwed rod U₁ carries at one
end Va pinion with diagonal teeth, into which gears an endless screw or
worm W, the axis of which is fixed at right angles to the screwed rod, and..

page_text: passing through the sides of the steelyard is filed off flush therewith. A hole
K is made in each side of the steelyard, opposite to each end of the axis, by
inserting a key into which the worm W. may be turned round, and the adjust-
ing weight T made, by means of the screwed rod U, either to advance towards
or recede from the point of the steelyard, according as the state of the equi-
librium of the, machine may from time to time require. If desired, the key
may be dispensed with, and a head with a milled edge be fixed to, the worm,
or the internal adjusting bar may be moved by a rack and pinion, or any
other equivalent mechanical means. By thus constructing the steelyard, the
most perfect. equilibrium may be at all times preserved in the weighing
machine, without any risk of disturbance from external causes. The adjusting
weight is placed not only out of sight, but out of the reach of persons who
might from curiosity, or mischief, or fraud, desire to meddle with the balance;
and it is capable at the same time of being regulated with perfect ease by the
person in charge. It is besides wholly free from liability to accidental altera-
tion, which, in other machines, often occurs from moving the portable machines
from place to place. To relieve the knife edged bearings and other parts of
the machine from strain or wear, except when the machine is in actual use
for weighing, I adopt the following method:-Over the suspending shackle a,
Figures 3 and 8, of the steelyard, is placed a pulley b, Figure 5, which turns
freely on its axis c. To this suspending shackle is rivetted the first link of a
chain d, d, which passes over the pulley, and is connected at its other end by a
rode to another chain f, which is carried round a quadrant g, and terminates
in a screw bolt, which is inserted into the extreme end h of the quadrant,
where it is secured by a nut, the screwed end serving to give the exact regu-
lation of length to the chain. The quadrant g is. attached to a long and
powerful band leyer of wrought iron i, or, in other words, forms the short arm
of the compound lever i, g. The action is as follows:-Suppose the machine
is out of gear, or in a dormant or quiescent state, the long hand lever assumes
in that case a vertical position, as shewn by the dotted lines k, k; the steelyard
and main weighing levers are dropped down to the positions shewn also by
dotted lines in Figure 3, and the platform with its beams rests securely by
its bearing pieces o, o, upon the receiving props P, P. When the machine
is required to be put into a weighing state, the long hand lever i is drawn
from the vertical to the horizontal position, that is, from k to i, Figure 8, and
made fast in the strong catch or staple n, which is bolted to the pillar p.
The effect of this is to raise the steelyard, the weighing levers, and the plat-
form to the precise points for weighing. When the weight is ascertained, tho
hand lever i is released from its catch, and returned to the vertical position k,

page_text: when all the parts of the machine fall again into their former quiescent and
safe position, all the knife edged bearings and other parts being released from
contact, and safe from the effects of loads passing over the platform.
In some cases I make use of a supplementary steelyard X, as shewn in
Figure 14, in order to indicate the heavier weights, and thus obviate the
trouble and loss of time so often complained of in the case of machines which
require weights representing tons or hundredweights to be lifted and placed
on the plate of the counterpoise S, Figure 3.. In this arrangement the means:
of internal adjustment, before described, may be applied to either the upper or.
lower steelyard, as may be most convenient. When applied to the larger'
weighing machines, or weighbridges, the lower steelyard Y is graduated to parts.
from 1 lb. to 5 cwt., and the upper steelyard ✗ to tons, half tons, and quarter.
tons, up to the power for which the machine is adapted; and when this arrange-
ment is applied to the smaller machines; the upper steelyard is employed to:
represent the hundredweights, and the lower steelyard, pounds or ounces..
When the relieving apparatus is to be fixed to machines having the supple-
mentary steelyard, Figure 14, the compound leverage is connected to the lower:
steelyard, which, when it is lowered out of gear, leaves the upper steelyard at
rest upon its fulcrum t and guard s. To render also the working of the
relieving apparatus a still easier operation in the case of very large weigh-
bridges, I sometimes attach a large counteracting weight.X, X, by a common
chain to a quadrant Q, as shown in Figure 14, the' quadrant being keyed on
the axis Z of the long hand lever.
The weighing machine represented in Figures 1, 3, and 4, and before
described, is adapted for use upon railways, and is shewn in these Figures as.
so applied. It remains however to explain a peculiarity in the construction of
the platform, whereby any flow of water or mud into the pit, which is formed
to receive the machine (the accumulation of which is a frequent cause of
injury to such machines, and of inaccuracy in their indications) is wholly
prevented, and which improvement is equally applicable to the platforms of
weighbridges or turntables wherever placed. With this view, I make the
kirbs z, z, of cast iron, and in the form shewn in the section in Figures 3 and
4; the inner edges being turned up angularly as a flanch over the top of the
kirb so formed, the moulded edge y of the platform is brought as seen in
section in Figure 4. It is obvious that this shape of kirb and platform will
turn off any water that may fall upon them, whilst the improved relieving
apparatus, before described, by raising the platform from its quiescent.
position, will free the edge of the platform from contact with pebbles or
other matters which might otherwise affect the accuracy of the results. A

page_text: plan of the platform as fixed is given separately in Figure 15; R, R, are the
rails; C, C, chairs; P, the platform, and NH, is a manhole to to. give access
to the pit. for the purpose of cleaning or repair. I have described my
improved steelyard and relieving apparatus, as connected with a weighbridge,
with rectangular platform, and as adapted to a railway; but I wish it to be
understood that I do not confine myself to that particular shape.or application;
but that the platform may be circular, hexagonal; or of any other convenient
shape, and the machine be adapted as well to common roads as railways.
And although I have exemplified the nature of the improvements, constituting
`my said Invention, by shewing their application to a machine of the larger
class, called weighbridges, yet I wish it to be understood that these improve-
monts are equally applicable to weighing machines of a lesser size, such as are
used in warehouses, wharfs, and shops; and whether these lesser machines
are employed as fixtures or are moveable upon wheels or otherwise, making
such modifications only in point of dimensions or arrangement as differences of
circumstances may obviously require. It deserves further to be observed, that
in any of the forms aforesaid the steelyard may, if desired, be made separate
from and unconnected with the improved relieving apparatus, and also that
the relieving apparatus, before described,,may be used in combination with any
other kind-of-steelyard.
.
"
The manner, in which a platform weighing machine of any of the improved
forms of construction before described may be applied to the regulation
of the springs in locomotive engines, so as to adjust the impact of each pair
of wheels upon the rails, is represented in Sheet No. 2 of the Drawings
hereunto annexed. Figure 1 is a plan of a set of weighing tables or plat-
forms, A, B, C, with a principal line, or pair of rails R', R¹, passing over
them; and two other parallel lines or pair of rails R2, R2 (colored red), and
R³, R³ (colored green); each of these tables or platforms is connected with
a steelyard. of the improved construction before described, with its frame and
relieving levers as shewn in the longitudinal section, Figure 3, Sheet No. 1.
Now, supposing these tables, be in a dormant or quiescent state (that is
to say) with the long hand levers in the vertical position indicated by the
dotted lines. D, D, D, and the platforms with their beams resting by their
bearings O, O,. on the props P, P, P, P, then let a locomotive engine be
brought upon the machine along the rails R, R, till each pair of its wheels
rests upon one of the tables. When the engine is so placed, let the long hand
levers D, D, D, be brought down to the horizontal position, which will bring all
the parts of the machine into a weighing state. The steelyards will then
indicate, first, the gross weight of the engine, and, second, the weight imposed

page_text: on the rails by the leading, the driving, and the following wheels respectively,
and also (of course) the state of the springs by which the engine frame is
supported upon the axles. Should any of the pairs of. wheels appear to be
unduly loaded, the bolts by which the springs are made tight or slack may
be screwed or unscrewed until, in the judgment of the engineer, the driving.
wheels have their proper impact, and each of the other pairs of wheels bears
a suitable proportion thereto. But it may and does often occur that one of
the springs of a pair of wheels may not be properly adjusted, although the
entire weight indicated as borne by the pair of wheels is accurate; I thereforo
test the wheels separately in manner following:-The engine is first drawn on
the machine along the rails R³, R³ (colored red), when the three. wheels on
one side only of the engine are brought upon the tables, the wheels of the
opposite side being upon the permanent way. The indicated weight of
each of these three wlieels is noted, after which the engine is drawn off
to convenient points or switches, and again brought upon the tables along
the rails R³, R³ (colored green), whereby the weight of the wheels on the
opposite side of the engine is ascertained in like manner. The two sets of
results are then compared, and any disparity corrected by screwing or
unscrewing the springs until a perfect adjustment is effected. Should there
be a turntable of sufficient dimensions near the weighing tables, the engine
may be reversed upon it, and one of the three pairs of rails dispensed with.
When a locomotive engine has four wheels only, it may be regulated by any.
two of the set of three tables according to the distance between the centres
of the axles.
The mode of adapting the ordinary lifting or hoisting cranes to weighing.
purposes is represented in Figures 3, 4, 5, 6, and 7, Sheet No. 2. In
some cases much time may be saved by thus lifting and weighing by one
operation, and in others bodies may be weighed by means of a compound
apparatus of this description, which in consequence of their inconvenient.form
it would be difficult, if not impracticable, to place upon any platform weighing.
machine. Figure 3 is a side elevation partly in section, and Figure 4'a top.
plan of a weighing crane adopted to the above purposes. In its general form
it resembles a crane of an ordinary kind, and the wheel and barrell, pinion
shafts, and other hoisting parts, may be of any approved construction according
to the power required in the crane, or to the weight which it is intended to
lift. A represents a load hanging to the crane by a hook B and live pulley C;.
round. this pully C the chain passes and has its last link attached to the
peculiarly formed bearing hook D which is shewn separately on an enlarged.
scale in Figure 5 and. 6; Figure 5 being a front, and Figure 6.a side view..

page_text: The upper portion E forms a double shackle, the. holes in which have their
surfaces of hardened and polished steel; the hook is hung by, these holes upon
the knife edged centres F of the long lever G. This lever (G) is shewn as:
placed between the sides of a double jib, by which sides it is hid from view;
but the lever may be placed over or under a common or single jib, in which
case it would then be exposed to view. The fulcrum of the lever G is at H, and
may be either rigid or suspended in a link, as may be most convenient. The
longer end of the lever is prolonged to the centre of the pillar of the crane at
I, where it terminates in knife edged centres. From I is a connecting
rod K which descends to the steelyard at L, to which it is connected by a
shackle and knife edged centres. The steelyard itself, so far as regards
construction and adjustment, is similar to those before described, except
only that it is a lever of the second order having: its fulcrum at the
extremity of the shorter end; and instead of a suspended link sustaining
the fulcrum, that fulcrum forms part of a rod M which descends below
the steelyard and passes through a guide or eye N, in which it is at liberty
to move freely, so as to admit of a small extent of oscillating motion in the
steelyard in order to prevent any friction from rigidity. The disengaging
fulcrum rod M is shewn in detail in Figure 7. It has a frame O, within
which is fixed an eccentric wheel P, having its axis connected by proper
centres with the pillar of the crane. Upon the axis of the eccentric is keyed
a hand lever Q, the design of which is to relieve the centres. and all other parts
of the weighing machinery from strain or wear during the time of hoisting, and
at all other times, except when in the act of weighing. The manner in which
this effect is produced is as follows:-When the crane is used for hoisting
only, the hand lover Q is in the vertical position indicated by the dotted lines
R, and the shorter end of the steelyard and the long lever are raised to the
extent of the eccentric action, and the square bearing shoulders of the bearing
hook and shackle D are brought down to the stationary resting bed upon the
jib S. In this state the weighing apparatus is entirely quiescent, and the
crane is merely an ordinary hoisting machine. When a load is lifted by the
crane which it is desired to weigh, the hand lever R is drawn down to the
horizontal position at Q, and make fast to a staple or catch fixed to the bracket
T. By this movement the hand lever, acting acting by its eccentric wheel
upon the steelyard and long lever, raises the bearing hook and shackle from its
bed, and puts all the parts of the apparatus into a weighing state. As the
length of chain, between the bearing hook and shackle D and the body A to
be weighed, is liable to considerable variation, it will be necessary, in order to
accurate results, that the weight should be ascertained when the load to be

page_text: weighed is at one given height from the ground. For this purpose I make an
indicating link U in the chain, which is very obvious to the view, and which
link, on its arriving opposite to the indicator V, fixed upon the axis of the live
pulley C, marks the altitude at which the load may be accurately tested.
Upon the chain immediately under the hook and shackle D, is a large hollow
ball of cast iron W, having a cased passage through the centre (vertically) to
admit the chain, and being perforated by a screwed hole on its upper side X,
through which hole lead, either in a melted state or in the form of shot, is to
be poured into the chamber, for the purpose of counterbalancing the dead
weight of the parts composing the weighing apparatus; or the requisite coun-
terbalance may
be attached to the long lever if preferred, or provided for in
any other suitable way. After the crane has been first fixed, all subsequent
corrections of the balance may be effected by the internal steelyard adjustment
before described.
Having now described the nature of my said improvements, and the manner
in which the same are to be performed, I declare that though I have in the
course of the preceding description directed certain forms, proportions, and
positions to be given to different parts of my improved weighing machines, 'I
wish the same to be understood as exemplifications merely of the system on
which they are constructed, and that I reserve to myself a right to vary such
forms, proportions, and positions, according to circumstances, as long as the
same peculiar system of construction is observed, and the same general effects
are obtained. And I declare that the improvements that I claim as con-
stituting my said Invention are as follows:-
First, I claim the employment in weighing machines of steelyards having
moveable adjusting weights enclosed within the bodies thereof, as before
described.
Second, I claim the suspending of the fulcrum of the steelyard from com-
pound levers, and the other connected arrangements before described, whereby
the knife edged bearings of steelyard weighing machines are relieved from
strain or wear when not in actual use.
Third, I claim the employment in steelyard weighing machines of a supple-
mentary steelyard to indicate the heavier weights, as before described.
Fourth, I claim the combination of steelyards and relieving apparatus of
any of my improved forms of construction with railway turntables.
Fifth, I claim the construction of the platforms of the class of weighing
machines, called weighbridges, with edges overhanging flanched kirbs, as
before described.