Improvements in Beam-and-Scale Weighing Apparatus.
Year: 1892

page_text: Date of Application, 22nd June, 1892
Complete Specification Left, 15th Mar., 1893-Accepted, 29th Apr., 1893
PROVISIONAL SPECIFICATION.
Improvements in Beam-and-Scale Weighing Apparatus.
I, SAMUEL BANKIER, of 61, Granville Street, Glasgow, in the County of
Lanark, North Britain, Clerk, do hereby declare the nature of this invention to be
as follows, that is to say :-
My said invention has for its object to improve the construction of beam-and-
scale weighing apparatus so as to obtain increased accuracy and sensitiveness, with
quickness in coming to rest, at a moderate cost.
In carrying out my invention according to one modification I have the beam made
of steel or other suitable metal or material with, preferably, flat vertical sides, and
with a fulcrum pin projecting from both sides. The fulcrum pin is cylindrical and
rests on two horizontal surfaces, on which the pin rolls with any angular movement
of the beam. The horizontal bearing surfaces are formed in pieces, between which
the beam placed, and which are fixed to a pillar itself fixed in a sole or stand.
At the ends of the beam arc-shaped surfaces are formed the centres of which
surfaces are in the same straight line as the centre of the fulerum pin, and at equal
distances therefrom. The scales, which may be of any convenient form, are
suspended from the ends of the beam, each by two fine cords which lie upon the
arc-shaped surfaces. Each pair of cords may be the two sides of a looped single
piece which is held by a pin fixed in the top of the beam; or the two looped cords
may be held by a single spindle extending upwards from the middle of the beam,
which spindle also serves for having a weight screwed up or down upon it to raise
or lower the centre of gravity with the view of varying the sensitiveness of the
apparatus.
From the middle of the beam there extends downwards an arm, which is vertical
when the beam is horizontal, and which has formed or fixed on its lower end a
divided scale extending upwards towards each side, the divisions of the scale being
designed to show small differences of weight corresponding to inclinations of the
beam. For indicating on the said scale there is provided a thread stretched
vertically by a small plummet at its lower end, and passing over the fulcrum pin
from a point a short distance from the fulcrum pin towards one end of the beam."
In other modifications the device of the rolling fulcrum pin and its horizontal
bearing surfaces may be combined with any suitable known construction of the
other parts. The device of the rolling fulcrum pin avoids friction and consequent
inaccuracy; and the device of the suspending cords lying on the arc-shaped surfaces
also avoids friction, as, with any angular movement of the beam the cords either
wind on or unwind off the surfaces to a small extent without any rubbing or sliding
action.
Dated this Twenty-first day of June 1892.
EDMUND HUNT,
Applicant's Agent.
COMPLETE SPECIFICATION.
Improvements in Beam-and-Scale Weighing Apparatus.
I, SAMUEL BANKIER, of 61, Granville Street, Glasgow, in the County of
Lanark, North Britain, Clerk, 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, that is to say :-
My said invention has for its object to improve the construction of beam-and-
scale weighing apparatus, so as to obtain increased accuracy and sensitiveness, with
[Price 8d.]

page_text: quickness in coming to rest, at a moderate cost; and it consists, principally, in
making the beam with a cylindrical fulcrum pin arranged to roll on one or more
horizontal or nearly horizontal surfaces..
And in order that my said invention and the manner of performing the same may
be properly understood, I hereunto append a sheet of explanatory drawings to be
hereinafter referred to, and showing two modifications of my improvements in beam-
and-scale weighing apparatus.
Figure, 1, of the drawings is a plan, and Figure, 2, a front elevation of one
modification of my improved apparatus.
Figure, 3, is an end elevation of a part of the beam and scale attachment.
Figure, 4, is a sectional elevation of parts of the apparatus.
Figure, 5, is a front elevation of a pendent arm having a scale on it.
Figures, 6, 7, and, 8, are respectively a sectional plan, a front elevation and a
sectional elevation showing a second modification of part of the apparatus.
In these drawings the same reference letters and numerals are used to mark the
same or like parts wherever they are repeated.
According to my first modification I have the beam, A, made of steel, or other
suitable material or metal, with preferably flat vertical sides, and with a fulcrum
pin, A 1, projecting from both sides. The fulcrum pin, A 1, is cylindrical, and rests
on two horizontal surfaces, B, on which the pin rolls with any angular movement
of the beam, A. The horizontal bearing surfaces, B, are formed in two pieces, B 1,
between which the beam, A, is placed, and which are fixed to a horizontal arm, C,
on a pillar, D, itself fixed in an ordinary sole or stand, E. At the ends of the
beam, A, arc-shaped surfaces, A 2, are formed, the centres of which surfaces are in
the same straight line as the centre of the fulcrum pin, A 1, and at equal distances
therefrom. The scales, G, which may be of any convenient form, are suspended
from the ends of the beam, A, each by two fine cords, G 1, which lie upon the
arc-shaped surfaces. Each pair of cords, G 1, may form the two sides of a looped
single piece, which is held by a pin, H, fixed in the top of the beam, A, or if
desired the two looped cords, G 1, may be held by a single spindle (not shown)
extending upwards from the middle of the beam, A, which spindle would also serve
for having a weight (not shown) screwed up or down upon it to raise or lower the
centre of gravity with the view of varying the sensitiveness of the apparatus.
Single cords or bands may be used instead of the pairs of cords, G 1, if desired.
From the middle of the beam, A, there extends downwards a pointer, A 3, which
is vertical when the beam is horizontal, and which indicates on a scale, J, extending
upwards towards each side, on an arm, J 1, provided for the purpose, by graduations
designed to show small differences of weight corresponding to inclinations of the
beam. The said scale arm, J 1, is suspended on a knife edge formed on a piu, J 2,
fixed in one of the pieces, B 1, so as to hang plumb. Or if desired although not
shown the scale arm, J 1, may be formed on the beam, A, and for indicating on the
said scale, J, there may be provided a thread stretched vertically by a small
plummet at its lower end, and passing over the fulcrum pin, A 1, from a point a
short distance from the fulcrum pin towards one end of the beam.
To obviate any inaccuracy which might result from the sole or stand, E, being
placed on a surface which is not quite level, and thereby cause the bearing
surfaces, B, to be slightly inclined I adopt a modification shown in Figures, 6, 7,
and 8, of some parts of my apparatus. I suspend the pieces, B 1, by a pin, K,
fixed in them and which rests and can roll on a bearing surface formed on a
bracket, L, which is fixed to the pillar, D. I also have the bearing surfaces, B,
slightly curved, preferably concentrically with the pin, K, which suspends the
pieces, B 1. The pin, K, may, if desired, be made with a knife edge on its under
part, to rest on the bearing surface of the bracket, L, or conversely, the bracket
may be formed with a knife edge, the pieces, B 1, being in that case adapted to rest
on such knife edge. The parts, B1, and their top connection, M, are by preference
made so that their centre of gravity coincides with the knife edge or with the axis
of the pin, K.

page_text: The device of the rolling fulcrum pin, A 1, and its horizontal or nearly horizontal
bearing surfaces, B, may be combined with any suitable known construction of the
other parts. The device of the rolling fulcrum pin, A 1, avoids friction and
consequent inaccuracy; and the device of the suspending cords, G 1, lying on the
arc-shaped surfaces, A. 2, also avoids friction, as, with any angular movement of the
beam, A, the cords either wind on or unwind off the surfaces to a small extent
without any rubbing or sliding action.
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:
In beam-and-scale weighing apparatus, constructing the beam with a cylindrical
fulcrum pin, arranged to rest and roll on one or more horizontal or nearly
horizontal surfaces, substantially as and for the purposes hereinbefore described.
Dated this Fourteenth day of March 1893.
EDMUND HUNT,
Applicant's Agent.