Year: 1888

page_text: Date of Application, 3rd Feb., 1888
Complete Specification Left, 1st Nov., 1888
Complete Specification Accepted, 31st Dec., 1888
I, HENRY ALLCHIN, of 278 Mile End Road, London, E., Scale Manufacturer, do
hereby declare the nature of this invention to be as follows:-
This invention is designed to ensure greater accuracy in those descriptions of scales
known as
"Counter weighing Machines" of various sizes and patterns and it is also
applicable, more or less, to "sack weighing machines" and other kinds of weighing
apparatus, wherein the scales which receive the articles to be weighed are above the
scale beam instead of being below them, as in the case of the ordinary suspended scales.
In applying my invention to these "Counter weighing machines
I do not propose
to alter the beam which is of the ordinary pattern. My improvements affect the con-
nections which preserve the equilibrium of the scales during the rise or fall of the
beam, and communicate reciprocal movement from one scale to the other.
The novelty in my invention consists mainly in making the horizontal connecting
bar which I will call C, vibrate on a central fixed fulcrum B, which is not itself
vibrating.
Contrary to the usual practice I place the two striking points of B in a line and I
also reverse the position of C so that the two lugs which engage the striking points
of B project upwards instead of downwards, both faces of the said lugs being also in a
line, so as to engage accurately with B, and vibrate without altering the adjustment of
the scale.
At each end of C is a shoulder and projecting tongue of metal on which I rivet two
small plates D, each having a hook on one end alternately to each other. These plates
form guides and interlocking attachments for two vertical connecting bars A which
descend from the scale and terminate in a double hook of the ordinary pattern, which
interlocks with the plates D, in such a way, as to be held in contact therewith while
having the necessary amount of play to allow of the movements of the scales.

page_text: It is important to notice that the various parts A B and D have at their striking
places or points of contact, sharp or knife edges so as to minimise frictions and that
when fixed in position only one of the two plates D projects, far enough to allow of
its 'edge bearing against A.
The foregoing arrangement and formation of parts has the effect of reducing friction
and preventing the variation or unjust actions of the scales, which sometimes results
from the old method of construction in which the fulcrum was made to vibrate, and in
which the horizontal connecting bar C was liable to be bent by a load placed out of
the centre of the scale, and when bent caused the scale to weigh incorrectly.
Dated this 3rd day of February 1888.
S. S. BROMHEAD,
97, Newgate Street, London, E.C.,
Patent Agent.

page_text: COMPLETE SPECIFICATION.
Improvements in Weighing Machines.
L, HENRY ALLCHIN of 278 Mile End Road London in the County of Middlesex,
Scale Manufacturer 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:-
"
This invention is designed to ensure greater accuracy in those descriptions of scales
known as
"Counter weighing machines," and "Weighing Machines of various sizes
and patterns, and it is also applicable more or less to other kinds of weighing apparatus
wherein the scales which receive the weights and articles to be weighed, are above
the scale beam, instead of being below them, as in the case of the ordinary susponded
scales.
In applying my invention to Counter weighing machines, 1 do not alter the beam
which is of the ordinary pattern.
My improvements affect the connections which in this pattern machine are placed
below the beam, but which are placed above the scale in certain kinds of machines.
These connections preserve the equilibrium of the scales during the rise or fall of the
beam and communicate reciprocal movement from one scale to the other.
In the accompanying drawings,
Fig. 1 shows the working parts of an ordinary Machine Scales with the usual con-
nections below the beam. A. A, are two vertical bars attached at their summits to the
scales. B is the fulcrum which usually oscillates to and fro. is the horizontal lever
or connecting bar. Some of the defects of this arrangement are that the bar C.
may become bent by a heavy weight being placed suddenly in one of the scales,
and the length of the leverage would thereby be altered, the balance of the scate
being impaired so that it would no longer weigh correctly.
Another defect is that through the swinging motion at the fulcrum much play
and consequent friction are caused and a heavy lateral strain is sometimes suddenly
communicated from one of the bars A, to the other, which tends to bend or break
them thus impairing the efficiency of the scales.
Fig. 2 shows a set of connecting parts to go below the beam, constructed on my
system the vertical bars A being shewn detached.
It will be seen that in this arrangement the fulcrum B is fixed and stayed from
each side so that lateral thrust from A to A is impossible.
Moreover as the horizontal bar C, cannot oscillate all unnecessary play is avoided
and as the bar C vibrates on the fulcrum B, the rise and fall motion of the vertical
bars A, A, is rendered steady but is not in any way impeded. The efficient action of
the whole is rendered easy by the use of interlocking hooked bearings K with knife
edges at all working points as shown in the drawings in Figs. 2, 3, 4, 5 and 6.
These bearings have forks engaging with striking points of knife edge section, the
knife edges which interlock with the forks being in all cases in line with each other
at each bearing so that the vertical action of the scale is guided and steadied, with a
minimum of friction and with, great accuracy.

page_text: In the drawing furnished herewith
Fig. 3 Shews a perspective view of the fixed fulcrum.
Fig. 4 Shews a plan of the same.
Fig. 5 Shews a perspective view of the horizontal bar C.
Fig. 6 Shews a plan of the same.
Fig. 7 Shews a front view of one of the end plates enlarged.
Fig. 8 Shews a back view of ditto enlarged.
Fig. 9 Shews a plan of the hook bearing on the vertical bar A enlarged.
It will be obvious from an inspection of the drawings that there is no probability of
a weight on either scale bending the bar C, or displacing the vertical bars A, A.
At each end of the bar C is a fork or pair of lugs J, projecting downwards and
fitted to engage with the hooked bearing K on the vertical bár A. This fork may be
cast solid with the bar C, or may be formed of the two plates D, each having a lug on
one end alternately to each other and being fitted on a tongue at the end of Cas shown
in Fig. 2. These forks in either case present only a knife edge to the hooked bearing K.
If preferred any of these hook and fork bearings may be reversed so that the hook
shall be above the fork, or the fork above the hook.
16
It should be mentioned that the hook bearing K of the vertical bar A admits of any
required amount of play being allowed as a slight twist of the vertical bar will slacken
it if too tight, and tighten it if too slack. In an Imperial" or "inverted" pattern
machine, the connections are above the scale and beam, and the fulcrum is not always
employed, but in the case of the fulcrum being omitted. two forked-end connecting
bars are used instead of one, each being a straight bar, with ends similar to those shown
on Fig. 2 (D) or cast solid as hefore described. In that case the hook K would be
mounted on a horizontal shank, or angular bracket so as to hold it in its horizontal
position on the pillar or column of the scale.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what
I claim is;
1. In a weighing machine with beam below the scales a vibrating connecting bar
or lever with fixed fulcrum and with forked or hooked ends as herein explained and
set forth.
2. In a weighing machine as before described the interlocking hook and fork, or
fork and eye bearings, with fixed striking points of knife-edge section, the said points
being set in line as herein described and set forth.
3. In the working parts of a weighing machine a terminal fork or hook or the
terminal plates D forming together a fork, to engage with the hooked bearing K. as
herein explained and set forth.
Dated this 1st day of November 1888.
S. S. BROMHEAD,
97, Newgate Street, E.C.,
Patent Agent.