IMPROVEMENTS IN MACHINERY OR APPARATUS FOR ASCERTAINING AND INDICATING WEIGHT
Year: 1877

page_text: LETTERS PATENT to Thomas Henry Ward, of Smethwick, near Birmingham,
in the County of Stafford, for the Invention of "IMPROVEMENTS IN MACHINERY
OR APPARATUS FOR ASCERTAINING AND INDICATING WEIGHT."
Sealed the 26th March 1878, and dated the 4th October 1877.
PROVISIONAL SPECIFICATION left by the said Thomas Henry Ward at the
Office of the Commissioners of Patents on the 4th October 1877.
THOMAS HENRY WARD, of Smethwick, near Birmingham, in the County of
Stafford. "IMPROVEMENTS IN MACHINERY OR APPARATUS FOR ASCERTAINING AND
INDICATING WEIGHT."
My Invention relates more particularly to that description of suspension weighing
apparatus in which the weight of a load is ascertained by weighing a proportion
or component part thereof, and thence determining the total weight upon the prin-
ciple of the parallelogram of forces, examples of which apparatus are described in
the Specification to Letters Patent granted to me, dated the 6 November 1876,
No. 4294; and my Invention has partly for its object producing an apparatus
which shall be self-contained, and the whole of the parts of which shall be com-
prised within a limited space; and also obtaining simplicity and economy in the
construction of the apparatus, whether the Invention is applied to suspension or
self-contained apparatus, or to platform weighing machines, or to other like apparatus
for ascertaining weight.
In applying my Invention to the construction of a suspension or self-contained
apparatus, in order to effect these objects, I employ a rocker, which is carried in-
bearings in the jaws of a bifurcated frame, and in a central shackle surmounted by
a loop or ring for the facility of suspension. This rocker, which acts also as a pin
connecting the shackle to the machine, and is constructed of such a section that
two of its edges are utilized as the upper and lower knife edges, such, for example,
as two angles of a square, is placed at an angle; that is to say, so that a line drawn
through its knife edges will be inclined to the vertical plane, but the parts are so
-

page_text: arranged that the rocker, in its normal condition, whilst still being inclined, shall
approximate as closely as practicable to a vertical position.
A cushion of india-rubber, or other yielding material, may if desired be inter-
posed between the knife edge and the shackle for the purpose of diminishing con-
cussion in the knife edges.
The frame above mentioned, which is forked at both ends, carries a hook at the
lower end suspended loosely by a pin shaped to a knife edge bearing, for the sake
of greater accuracy, and thereby ensures the machine always being suspended in
one constant vertical position. The rocker is fixed or fitted to a lever arm, which
is connected directly at or near its lower end to a spring balance, and is also
attached, by preference, at a point situate intermediate between its fulcrum and its
lower extremity, to a vibrating lever mounted on a fixed centre, and carrying a
segment which imparts motion through the intervention of a pinion to a pointer for
indicating upon a dial the weight of the load to be ascertained.
The spindle of the pinion, and which also carries the pointer, passes through a
hole in the vertical frame, or if preferred at the side of the frame, to which latter
is secured a frame for carrying the dial and the fulcrum of the vibrating lever seg-
ment; and a casing cast in one with the frame or otherwise is further provided for
enclosing the whole of the working parts.
The apparatus operates in the following manner :- -When a load is attached to
the hook, the rocker, which naturally inclines a little, is caused to turn slightly on
the lower bearings of its top knife edge, and the load is deflected (the degree of
such motion and deflection varying in proportion to the amount of the load, but
being so arranged as to be as small as it is practically possible, for example, say
of an inch; and, as the pendent lever arm works in unison with the rocker, the
fornier is also caused to turn, thereby elongating the spring of the balance by an
amount greater than the deflection in rocker due to the leverage of the lever, and at
the same time imparting motion to the vibrating lever segment by an amount still
greater than before, due to the extra leverage of the quadrant lever which actuates
the pointer. It will thus be seen that, in lieu of weighing the entire load, a com-
ponent part thereof only is weighed, which is represented by the amount of
deflection, and that as the degree of deflection varies with the load, that when the
resistance of the spring is brought to bear upon it the arc, which the pendent lever arm
has described when it arrives at its position of rest with the load, and the spring, in
equilibrio, will be in proportion to the amount of deflection, and consequently to
the weight of the load by suitably graduating therefore the dial, and proportioning
the dimensions of the several moving parts, the total weight of the load will be
ascertained from its component upon the principle of the parallelogram of forces.
When my Invention is applied to a platform weighing machine I employ rockers,
arranged in the manner herein-before described, and in any number required for
carrying the platform, as, for example, two or four rockers may be used separately
or in connected sets, a set consisting of, say, two rockers connected together by
tubular or other connecting rods or bars. One of the rockers or one of the sets
of rockers, or their connecting bar carries a lever arm situate in a plane approxi-
mating to the horizontal, the extremity of which lever arm is connected by a rod
arranged vertically, or otherwise, without the intervention of intermediate bell-
crank levers or other gear to a spring balance and indicating apparatus similar to
those of the self-contained or suspension apparatus herein-before described, or if
desired, to one or more levers ordinarily known as the graduated levers of a weighing
machine.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Thomas Henry Ward in the Great Seal Patent Office on the 4th April
1878.
THOMAS HENRY WARD, of Smethwick, near Birmingham, in the County of
Stafford. "IMPROVEMENTS IN MACHINERY OR APPARATUS FOR ASCERTAINING AND
INDICATING WEIGHT."
My said Invention relates to suspension weighing apparatus of that description
in which the weight of a load is ascertained by weighing a proportion or component
part thereof, and thence determining the total weight upon the principle of the
parallelogram of forces, examples of which apparatus are described in the Specifica-
tion to Letters Patent granted to me, dated the Sixth November, One thousand
eight hundred and seventy-six, No. 4294, and my said Invention has for its object
producing a suspension apparatus, more especially intended to be used in combination
with cranes, which shall be self-contained, simple, compact, and powerful, and
economical in its construction, and the whole of the parts of which shall be comprised
within a limited space or compass.
In carrying out my said Invention in order to effect these objects, I connect the
shackle or suspension device by which the apparatus is supported with the hook or
suspending device which carries the load to be weighed, by means of a frame con-
stituting the body of the machine, the upper end of which is attached to the
said shackle or suspension device by a rocker formed on its upper and lower
sides, with knife edges, and made of the minimum height practicable, so as to
perform, in addition to its function as a rocker, that of a pin or key for con-
necting the parts together, whilst the lower end of the said frame is either
attached to the hook or suspending device by a pin formed with a knife edge,
so as to ensure that the frame or body of the machine is always suspended in a
constant vertical position, or by the hook or suspending device being itself provided
with a knife edge engaging with the frame for a like purpose.
The rocker is placed at an angle, that is to say, so that a line drawn through its
knife edges will be inclined to the vertical plane, but the parts are so arranged that
the rocker in its normal condition, whilst still being inclined, shall approximate as
closely as practicable to a vertical position, say at an angle of about five degrees. To
the rocker is fixed or fitted a lever arm, which is connected directly at or near its
lower or outer end to a spring balance, and is also attached by preference at a point
situate intermediate between its fulcrum and its lower extremity to a vibrating lever
mounted on a fixed centre, and carrying a toothed segment which imparts motion
through the intervention of a pinion to a pointer for indicating upon a dial the
weight of the load to be ascertained.
The spindle of the pinion, and which also carries the pointer, passes through a hole
in a bracket carrying the indicating gear, which bracket is screwed into the vertical
frame; or if preferred, it may be arranged at the side of the frame; the bracket also
serves to secure the dial to the machine, whilst an arm of the bracket which carries
the fulcrum of the quadrant with its appendages, projects through into a fixed box
provided for the purpose of protecting the whole of the working parts.
The apparatus operates in the following manner :- When a load is attached to the
hook, the rocker, which is normally somewhat inclined, is caused to turn slightly on its
lower knife edge, and the load is deflected (the degree of such motion and deflection
varying in proportion to the amount of the load, but being so arranged as to be assmall
as it is practically possible; for example, say, in a one ton machine one fifty fifth of an
inch and as the lever arm works in unison with the rocker, the former is also caused
to turn, thereby elongating the spring of the balance by an amount greater than the
deflection in the rocker, in the proportion to the increased leverage of the lever over
the tumbler, and at the same time imparting motion to the vibrating lever, segment
which actuates the pointer, and causing the said lever to describe a longer arc than
the lever arm, so as to obtain a maximum or augmented stroke of the pointer upon
•

page_text: the dial for the facility of reading the indications. It will thus be seen that in lieu
of weighing the load upon the principle of the lever, as is customary in weighing
machines, it is weighed upon a combination of the principles of the lever and the
parallelogram of forces, and that as the degree of deflection varies with the load, and
is resisted by the spring, the arc which the lever arm has described when it arrives
at its position of rest with the load, and the spring in equilibrio will be in propor-
tion to the amount of deflection, and consequently to the weight of the load by
suitably graduating therefore the dial, and proportioning the dimensions of the
several moving parts, the total weight of the load will be ascertained upon the
principle before described.
A weight or weights or other equivalents may be substituted for the spring
balance, and the vibrating lever, segment, pinion, dial, and pointer and appendages
may be dispensed with, the weight of the load being ascertained by the addition
of, or the sliding of weights, or both, after the manner of weighing with ordinary
levers.
And in order that my said Invention may be fully understood, I shall now
proceed more particularly to describe the same, and for that purpose shall refer to
the several Figures on the annexed Sheets of Drawings, the same letters of reference
indicating corresponding parts in all the Figures.
Figures 1 to 7 Sheet 1, of the accompanying Drawings, illustrate one modification
of apparatus for ascertaining and indicating weight constructed according to my
said Invention, Figure 1 being a front elevation; Figure 2, a back elevation with
the cover removed; Figures 3 and 4, longitudinal and transverse sectional elevations;
Figure 5, an end view; Figure 6, a sectional plan through the box only, corresponding
to Figure 2; and Figure 7, an enlarged detail of the rocker and the contiguous
portions of the frame and shackle.
Figures 8 and 9, Sheet 2, illustrate in transverse and longitudinal sectional
elevation another arrangement of shackle frame and hook in accordance with my
said Invention; and Figures 10, 11, and 12 (Sheet 2) illustrate a further modi-
fication, Figure 10 being a front elevation; Figure 11 a sectional plan, and
Figure 12 an end view of the same; Figure 12a is a transverse sectional elevation
illustrating another modification of the rocker.
Referring to the arrangement illustrated by Figures 1 to 7, A is the shackle or
suspension device, by which the apparatus is supported, and B is the hook or
suspending device for carrying the load to be weighed, the two parts being con-
nected together by means of a frame C, which at its upper end is attached to the
shackle A by a rocker D, and at its lower end carries the hook B formed with a
knife edge at a, in order to ensure that this frame shall be always suspended in a
constant vertical position. The rocker D, which is formed with knife edges on its
upper and lower sides at b, c, respectively, is made of the minimum height practicable,
so as to admit of its being utilized as the means of connecting the frame C and
shackle A together without the aid of additional pins, the rocker itself constituting
the pin for uniting the two parts, which are made of a hook shape at d, e, to engage
with the knife edges b, c, respectively. The rocker D is placed at an angle; that is
to say, so that a line 1, 2, drawn through the knife edges b, c, will be inclined to
the vertical plane 3, 4, but the parts are so arranged that the rocker in its normal
condition whilst still being inclined shall approximate as closely as practicable to a
vertical position. To the rocker D is fixed or fitted a lever arm F, which is
connected near its lower end to one extremity of a spring G, the opposite extremity
of which is secured to one of the sides of a box H in which the various operating
parts or gear are located, and at a point above the spring G there is attached to
the said lever arın F by means of a rod f one arm g of a double armed vibrating
lever I, which is mounted on a fixed centre at h in a bracket K screwed into the
frame C. This vibrating lever is provided on its other arm with a toothed
segment i, engaging with a pinion mounted on one end of a spindle l, which
passes through the boss of the bracket K, and carries at its opposite end a pointer L

page_text: for indicating the weight of the load to be ascertained upon the dial M carried by
the bracket K.
The frame C is provided at its upper end with a projection m engaging with a
recess in the shackle A for the purpose of preventing any liability of the accidental
disengagement of these parts of the machine, and the lower part of the frame is
provided with a screwed pin n engaging with a recess in the hook B for a like
purpose.
The lever arin F is fitted with a stop o for limiting its motion in both directions
and also for protecting the spring from undue strain, which stop is adjustable in
order to admit of the position of the lever being regulated in setting the apparatus.
The spring G and the rod f are formed with right and left hand screw threads for
facilitating the adjustment of their proper connections. It is preferred to make the
working edges b, c, of the rocker D slightly rounded, as shewn in the enlarged
detail, Figure 7, in lieu of forming them to a sharp angle.
By constructing however the rocker of the best steel with hardened knife edges
the latter may be made sharper than would be otherwise admissible without the
liability of their being unduly flattened in wear. The box H which contains the
whole of the gear or working parts is represented as attached to the frame C, and a
cover N is provided which closes the box.
:-The apparatus
The operation of weighing is carried out in the following manner :-
being by its shackle or suspension device A fixed to or suspended from any body or
support, the load to be weighed is attached to the hook B, the point of suspension
of which at a is in the vertical line 3, 4, passing through the upper knife edge b of
the rocker D.
When the load is attached to the hook the rocker D, which is normally somewhat
inclined, is by the weight of the load caused to turn slightly to the right on the
bearing of its knife edge at c, in the shackle A, into the position indicated by the
dotted line 5, 6, in Figure 7, and the load which still depends vertically from the
knife edge b has thus been deflected to an infinitesimal extent, which is represented
(slightly exaggerated) by the distance between the vertical line 3, 4, and the vertical
line 7, 8, in Figure 7, the degree of the motion of the rocker and of the deflection of
the load varying in proportion to the amount of the load. As to the lever arm F
works in unison with the rocker D, it follows that the former is also caused to turn,
thereby elongating the spring G by an amount exceeding that of the deflection of
the rocker in proportion to the increased leverage of the lever over the rocker (the
resistance of the spring being received by the lever in its functions as a lever rather
than of a pendulous arm); at the same time motion is imparted to the vibrating
lover I, the segment of which actuates the pinion for transmitting motion to
the pointer L, the arc described by the segment i being still greater than that
described by the lever arm F, so that with a minimum or minute deflection of the
rocker D there is obtained by the arrangement and combination of gear herein-before
described a maximum or augmented stroke of the pointer L, upon the dial M, and
the reading of the indications is accordingly facilitated. It will thus be seen that
in lieu of weighing the load upon the principal of the lever, as in ordinary weighing
machines, in the apparatus constructed in accordance with my said Invention it is
weighed upon a combination of the principles of the lever and the parallelogram of
forces, and that as the degree of deflection in the rocker varies with the load, and is
resisted by the spring, the arc which the lever arm F has described when it arrives
at its position of rest, with the load and the spring in equilibrio, will be in proportion
to the amount of deflection, and consequently to the weight of the load, by suitably
graduating therefor the dial M, and proportioning the dimensions of the several
moving parts, the total weight of the load will be ascertained upon the principles
herein-before described.
In the modification, illustrated by Figures 8 and 9 (Sheet 2), the frame C is made
bifurcated at its opposite ends to embrace the shackle A and the hook B respectively,
the rocker D serving as the connecting pin between the shackle A and the frame C,
as before, whilst the hook B is also attached to the frame by a pin D', shaped to a

page_text: knife edge at a¹². The other parts of the apparatus, not shewn in the Drawings
(Figures 8 and 9), are similar to those of the apparatus herein-before described with
reference to Figures 1 to 7. The mode of connecting the hook to the frame by means
of a pin formed with a knife edge, as shewn in Figures 8 and 9, may also be adapted
to the arrangement of frame shewn in Figures 1 to 7 of the Drawings.
According to a further modification of my said Invention, which is illustrated by
Figures 10, 11, and 12, Sheet 2 of the Drawings, the spring balance G, segmental
lever I, pinion k, pointer L, and dial M, and their appendages are dispensed with,
whilst the frame is shortened, and the lever F, which in this case is made of such a
shape as to encircle or embrace the frame, and is arranged horizontally in lieu of
vertically, has suspended from its outer end weights G' which control the motion of
the lever F, when the rocker D is turned on the bearing of its lower knife edge at c,
under the weight of the load, the outer end of the lever being protected by an arm
or bracket C extending from the frame C, and which carries the stop o¹ for control-
ling the deflection, and is balanced by a counterweight at C. The lever F at the
opposite end to that at which the weights G₁ are suspended, is screw-threaded for
the reception of an adjustable counterweight C³, which however is not manipulated
in connection with the operation of weighing.
In order to determine the weight of the load suspended from the hook B; weights
are to be added at G2, until the lever F is depressed on to the stop pin o¹ of the
projecting arm C¹, then the balance weights are to be adjusted until the lever rises;
or the lever may be graduated, as shewn, and the weight of the load ascertained by
moving along it a sliding weight O, until the lever starts from off its stop, or in the
case of heavy loads beyond the range of the graduated scale, the weight may be
taken approximately by the addition of weights at G2, and a nice adjustment of the
lever F, obtained by sliding the weight O.
Although I have shewn this modification of the lever F and gear, as applied to a
frame C, constructed and arranged in a similar manner to that of the apparatus
illustrated by Figures 1 to 7, Shect 1, it is obvious that the frame may be constructed
and may be connected to the shackle A and hook B in the manner herein-before
describod with reference to Figures 8 and 9 (Sheet 2) of my Drawings, if
preferred.
In the case of each modification, care should be taken to have all the working
parts free of action, especially at the sides of the lever and shackle, and this will be
better ensured by recessing the rocker, as shewn at o², in Figure 120, so that the
shackle bearing and the frame bearing will drop into position between its inclined
recesses, and thus avoid the side rubbing surfaces entailed in the arrangements
previously described.
Having now described and particularly ascertained the nature of my said Inven-
tion, and the manner in which the same is or may be used or carried into effect, I
would observe in conclusion that I do not intend to confine myself to the precise
details and forms shewn in the accompanying Drawings, as it is obvious that the
apparatus is susceptible of slight modification without altering the principle, as, for
example, the dial may form the lid of the box by a slight re-arrangement in the
gear, the rocker may vibrate inwards in lieu of outwards, and it may be connected
to a pair of levers instead of to one lever only; the shackle may be arranged as a
fixture in lieu of hooking to a support, and the shape of the frame may be varied,
and the normal inclination and likewise the height of the rocking pin may also vary
slightly, but what I consider to be novel and original, and therefore claim as the
Invention secured to me by the herein-before in part recited Letters Patent is,-
First. In a suspension machine or apparatus for ascertaining the weight of a load
by weighing a small proportion or component part thereof, and thence determining
the total weight upon the combined principles of the lever and of the parallelogram
of forces, the employment of a pin or key which, in itself, constitutes a knife edge
rocker, and is arranged normally inclined, but approximately as nearly as practicable
to a vertical line, and so as to vibrate through a minimum or minute are, the said
rocker being attached to a lever, which is resisted in its function as a lever in

page_text: contradistinction from that of a pendulous arm by means of one or more springs,
weights, or their equivalents, substantially as herein-before described.
Secondly. In a suspension machine or apparatus of the description herein-before
referred to, connecting the shackle or suspension device by which the apparatus is
supported with the hook or suspending device which carries the load to be weighed,
by means of a frame attached to the shackle or suspension device by a pin or key,
which, in itself, constitutes a knife-edge rocker, and is arranged normally inclined,
but approximating as nearly as practicable to a vertical line, and so as to vibrate
through a minimum or minute arc, the said rocker being attached to a lever which
is resisted in its functions as a lever in contradistinction from that of a pendulous
arm, by means of one or more springs, weights, or their equivalents, substantially as
herein-before described.
Thirdly. In a suspension machine or apparatus of the description herein-before
referred to, the combination with the shackle or suspension device A, hook or sus-
pending device B, connecting frame C; and rocker D of the lever arm F, the
segmental lever I, pinion k, hand or pointer L, and dial M, the whole being
constructed and arranged so as to operate substantially in the manner and for the
purposes herein-before described, and as illustrated by Figures 1 to 9 of my
Drawings.
In witness whereof, I, the said Thomas Henry Ward, have to this my
Specification set my hand and seal, this Twenty-ninth day of March, One
thousand eight hundred and seventy-eight.
THOMAS HENRY WARD. (L.B.)