Improvements in Weighing Machines.
Year: 1894

page_text: Date of Application, 10'h Mar., 1894
Complete Specification Left, 27th Oct., 1894-Accepted, 1st Dec., 1894
Improvements in Weighing Machines.
I, THOMAS WILLIAM MARK, of 12 Cook Street, Liverpool in the County of
Lancaster, Merchant, do hereby declare the nature of this invention to be as
follows:-
This invention relates to weighing instruments of the kind commonly known as
machine scales, counter machines, Anglo-French machines and vibrating counter
machines.
Hitherto such instruments have been constructed to weigh above the centre of
gravity in their weigh beams and require a system of secondary beams, tie or
connecting rods, or bottom dogs to keep the trays or receptacles (upon which the
articles to be weighed and the weights are placed) in an upright and horizontal
position above the centre of gravity of the scale beam.
Now by my invention I propose to dispense with the beforementioned secondary
beams, tie rods, and connecting or bottom rods, thereby reducing the number of
working parts and any unnecessary friction of the joints resulting from the use
of the same.
In carrying my invention into effect, the plan I prefer is to provide a system of
counterpoise weights for keeping the trays in an upright and horizontal position
above the centre of gravity. The weights themselves are located below the centre:
of gravity and are applied to each tray in such a manner as to be in exact
equilibrium and thus in no way injure the weighing efficiency of the instrument.
The actual weight which ought to be used greatly depends upon the weighing
capacity of the scale, this being designed so that the weight shall be sufficient to
keep not only the trays but also the loads upon them in a horizontal position and
prevent them falling or toppling over.
1001
WM. P. THOMPSON & Co.,
Of 6, Lord Street, Liverpool, Patent Agents for the Applicant.
Improvements in Weighing Machines.
I THOMAS WILLIAM MARK of 12 Cook Street, Liverpool, in the County of
Lancaster, Merchant, 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 relates to weighing instruments of the kind commonly known as
machine scales, or counter machines in which the trays, pans or receptacles provided
for the reception of the articles to be weighed, and also the weights are so placed as
to be one or both above the centre of gravity of their weigh beam, as distinct from a
beam scale in which the trays are hung from the ends of the beam and are below
the centre of gravity.
:
Hitherto such machine scales have required a system of secondary beams, tie or
connecting rods, or guide rods, to support the said trays, pans or receptacles (herein-
after called the trays) laterally, and keep them in an upright and horizontal position
above the centre of gravity of the scale beam and thus prevent them toppling over
and, pilling their contents.

page_text: Now by my invention, I dispense with the beforementioned secondary beams,
tie rods, connecting guide or bottom rods, thereby reducing the number of
working parts and any unnecessary friction of the joints resulting from the use
of the same.
In carrying my invention into effect, the plan I prefer is to provide a system of
pendulum counterpoise weights for keeping the trays in an upright and horizontal
position above the centre of gravity of the weigh beam. The counterpoise weights
themselves are located below the centre of gravity of the weigh beam of the
instrument. The actual weight of counterpoise which ought to be used greatly
depends upon the weighing capacity and description of the scale, this being designed
so that these counterpoise weights shall be sufficient to keep not only the trays but
also the loads upon them from falling or toppling over.
The arrangement will be easily understood by referring to the accompanying
drawing which shows the invention by way of example applied to one form or
pattern of weighing scale. In this A is the scale bean whose centre of gravity is
at a B the upright supporting the same, C C the trays, D D the rods and box,
ends pivoted at d to the scale beam and adapted to support the trays, E E the
counterpoise weights attached to or formed at or near the bottom of the rods D.
It will be seen that these weights keep the trays upright above the centre of
gravity a and prevent them toppling over when articles are being weighed.
The improvement expressed concisely, is a weighing instrument in which the only
point of touch with a fixed object is at a and yet has its trays above the centre of
gravity of the weigh beam. My invention also enables me to use in these scales
the open frame single beam A which has not hitherto been employed in scales of
the kind mentioned.
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 1
claim is :-
1. The improvement in weighing instruments of the kind set forth, whereby the
use of secondary beams, ties or rods is dispensed with, and the number of working
parts reduced, substantially as described.
2: In weighing instruments of the kind in which the articles are weighed in
trays or receptacles located above the centre of gravity of the. weigh beam,
the arrangement for keeping the trays in an upright position, without the use of
secondary beams or rods, namely forming the pivoted rods which support the trays
or receptacles at each end of the weigh beam, with counterpoise weights at or near
their bottom ends, these weights being below the centre of gravity of the weigh
beam of the instrument.
3. In a weighing instrument of the kind set forth, the combination of the weigh
beam A, the rods D D pivoted to the ends of the weigh beam and adapted to
support the trays, and the counterpoise weights E E attached to or formed at or
near the bottom ends of the rods, substantially as described.
Dated this 26th day of October 1894.
WM. P. THOMPSON & Co.,
Of Liverpool, Manchester, Birmingham, Nottingham, and London,
Patent Agents.