Improvements in Weighing Machines or Scales.
Year: 1892

page_text: Date of Application, 23rd Jan., 1892-Accepted; 23th May, 1802
COMPLETE SPECIFICATION.
Improvements in Weighing Machines or Scales.
We, ANDREAS FREYTAG, and PAUL KÄRSTEN, of Langenweddingen, Germany,
Manufacturers, 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 machines or scales, and it has for its object to
weigh the same or two different materials, either solid or liquid, continuously and
without the materials coming into contact with one another, either before, during
or after the weighing operation.
With our invention it is possible to weigh, in the same machine, two different
materials, say, for example, one solid and one liquid, always in the same proportion
to each other.
Our arrangement consists mainly of two scales or receptacles, which are, by
suitable mechanism, filled alternately with the material or materials to be weighed.
The new machine has these advantages over old machines (1) that within an
equal period of time, almost double the quantity can be weighed and (2) that with
the same amount of work, the new machine will last twice as long.
And in order that our said invention may be properly understood, we have
hereunto appended two explanatory sheets of drawings, whercon: -
Fig. 1 is a side elevation of the mechanism of the scales.
Fig. 2 is an end view, partly in section, of the mechanism Fig. 1.
Fig. 3 is a plan of the mechanism, Fig. 1.
Fig. 4 is a side view of the scales, with the mechanism in a different position
from Fig. 1.
Fig. 5 is a part longitudinal section, through the mechanism of the machine.
Fig. 6 is a detail view to an enlarged scale.
Fig. 7 shows, in longitudinal and cross section, a travelling weight for the
balance.
Referring to the drawings, whereon the same reference letters, wherever repeated,
indicate the same or similar parts.
As already mentioned, two receptacles or scales W, W, (Fig. 4) are fitted to the
machine, into which the material to be weighed is supplied automatically. In the
drawings, we have shown pipes R, R', as conveyers for the material. The efflux
from the conveyers is so regulated, in the manner hereinafter described, that it is
possible to arrange, at will, the quantity to be weighed. When the predetermined
quantity is reached, the efflux from the conveyers is automatically stopped and the
Scale or receptacle which has been filled, is emptied.
The beam of the balance consists of two parts, fitted together in exactly the
same manner and which carry, at the ends, the weighing scales. Each part or
bar A, A, of the beam, is, as usual, fulcrumed on knife edges, which are marked on
the drawing a, a¹. The knife edges on which the scales are slung, are marked b, b'.
An axle or shaft c connects the parts or levers B, B1 of the beam scale together.
These levers B, B¹ have, as usual, arms of equal length. Each part A, A, of the
beam has or may have cut-out-parts, as shown. At the extremities of these
levers B, B', are projections f", to which are fitted two bent rails C¹ and on these
bent rails C, weights Grun. The rails are fitted, one at each side of the
machine, as shown, and are so arranged that the centre of each is exactly below the
shaft or axle c. The swing of the rails C and levers B, B', is limited by stops g, g',
projecting from the downwardly bent ends of the beam. When one arm of the
levers B, Bi, rests on or is caught by the stops y or g¹, then, the lower half
of the rails C³, C³, is exactly parallel with the lowered part of the beam A, A¹
(see Fig. 1).

page_text: Instead of the weights G being suspended from a single pulley, as shown m
Figs. 1 to 5, they may be suspended from two pulleys, as shown at Fig. 7, so as to
facilitate their rapid movement.
When the beam of the balance is in the horizontal position and the scales are
balanced, as shown at Fig. 4, the weights G are exactly below the knife edges b',
on which one of the scales is hung. At the ends of the rails C, C', are adjustable
catches or stops h, ', which limit the movement of the weights G. These catches
or stops are capable of being slid along to a greater or smaller distance from the
centre of the rails, so as to increase or decrease, as the case may be, the movement
of the weights G. The rails C, C', are graduated for the purpose of enabling the
catches to be adjusted accurately. The graduations read from the centre to each
end of the rails.
On the inside of each part A, A, of the beam, are projecting supports, each
having a V shaped groove. In the grooves rest loosely the triangular ends d' of a
cross bar d. Mounted on each end of this bar is a small arm S, and, in its centre,
a lever E, having two arms (see Fig. 6). The lower arm of the lever has a small
As the weight D
roller e on it and the upper arm carries an adjustable weight D.
causes the lever E to be in unstable equilibrium, and as the shaft d, on which the
lever is rigidly fitted, has the bearing-edges d', it follows that the lever can easily
be tilted from side to side. The lower end of the lever E, as it is tilted from side
side, catches against one or other of the arms h, k, of a forked lever K, which latter
is firmly fitted on the cross bar c. The arms k, k, are slightly flexible and can be
drawn together or asunder, so as to limit the play of the lever E, by means
of micrometer screws, (not shown on the drawings).
Presuming the beam of the balance is in the position shown at Fig. 1, that is,
inclined to the right, then the slide-rail-arrangement is also inclined to the right
and rests on the right-hand stop g'. The weights G are also at the right-hand.
The weight D has the tendency to incline in the same direction, but, at the same
time, as the roller e at the lower end of lever E is caught against the arm of the
forked lever K, the lever E and also the weight is maintained in a position at right
angles to the beam A, A'. If, now, the beam is slowly turned into the horizontal
position, the lever E is still retained in the same position relatively with the beam,
until the latter lies exactly horizontal. The slightest movement beyond the
horizontal position, makes the lever E tilt over to the right hand (or in a reverse
movement to the left-hand) and catch against the arm of the forked lever K.
As the slide-rail-arrangement, and the beam is tilted over to the left, the forked
lever K, in consequence of its firm connection to the axle c, also inclines towards
the left so that the arm k¹, catching on roller e, brings back the lever E and
weight D to its normal rectangular position, in relation to the beam.
If the beam is again turned to the right hand, the action hereinbefore described
is repeated.
The opening between the arms k, k, of the forked lever K, is carefully adjusted,
so that, at the moment when the beam attains the horizontal position, the centre of
gravity of the weight D is beyond the axle d and the upper end of lever E, in
In this way the
consequence, is caused to tilt to the same side as the weight.
lever E is made to have an advance over the beam A, A¹. But this action must
not; of necessity, be allowed to have any influence on the exactness of the weighing.
It is counterbalanced by still allowing a small quantity of material to pass into the
corresponding scale, during the tilting movement.
By properly adjusting the opening between the arms k, k¹, of the forked lever K,
the advance of lever E over the beam, can be adjusted to a nicety, for every quantity
to be weighed, so that the scale always acts with perfect correctness.
The left side of the part A and the right side of the part A' of the beam, have on
them brackets L, l, in which rollers n, n', are carried. Carried on cross shafts P, P₁
are jointed levers H, H', and carried on cross shafts Q, Q', are tappets j, j'. The
material to be weighed flows into the scales from the tubes R, R', which have or
may have stop cocks O, O'.

page_text: The action of the apparatus is as follows:-
Supposing the balance is in the position, shown at Fig. 1. In this position the
cock is opened and the cock O' is closed. The liquid, if liquids are being
weighed, flows into the left-hand vessel W (Fig. 4). When a certain quantity of
liquid has flown into the left-hand vessel, it, and also the left-hand end of the beam,
will go down, and with the beam also the weighted end of the lever H, (which, for
the time being, rests on the roller » of bracket 1) until it strikes against the cut-out.
part of the tappet, when further downward movement of the lever H is stopped,
for the time being. The movement of the lever H, through the link T, partially
closes the cock O, so that further efflux of fluid from the tube R is but small.
When the horizontal position of the balance is reached, the lever E, with the
weight D, tilts over to the left, strikes the arm k¹ of the lever K, turns axle e and
the arm S on the axle, so that the latter, in its turn, strikes the lower end of the
tappet and sets free the lever H, which, at once, by its own gravity, falls down
and cuts off further supply of fluid from pipe R.
By the tilting over of the weight D, the centre of gravity of the balance
is transferred to the left-hand side, and, as a consequence, that side begins to fall.
The inclination to the left, causes the slide-rails C, C, also to incline to the left
and consequently the weights G slowly travel from the right-hand side to the left.
The left side of the balance, now, sinks right down and the weights run into their
farthest left-hand position and, at the same time, the lever E is pulled into a
rectangular position, relatively with the beam.
The going down of the left side of the beam is, of course, accompanied by a
corresponding rise of the right side. The rising of the right-hand side causes the
roller n' of the bracket to strike against the lever H¹ and lift it up so as to open
the cock O¹ on the tube R¹ and allow fluid to pass into the right-hand scale of the
balance, until the beam is again lowered.
When the scales go down and shortly before the lowest position is reached, the
plugs K, Fig. 4, which may be conical if so desired, and close the lower end of the
receptacles W, are made to strike against some obstruction, say, for example,
the connecting bridge of the balance, and are forced up, so as to leave an opening
at the bottom through which the scales can empty themselves. The plugs K
are made as large as possible, so that the discharge of the scales takes only a
short time.
The shape of the weights G, which we prefer to use, is shown at Fig. 7.
The balance might be so arranged as to weigh different quantities in each scale.
This is done by the use of a bar S¹ (Fig. 5), on which small balls are placed.
These balls are about double the weight of the sliding catches h, h¹, and are
movable along the bar. The bar S', which is graduated, is fixed on that side of the
parts A, A', of the beam, opposite to the brackets and . The necessary
uneven adjustment of both sides of the balance is effected by moving the small balls
along the bar.
It will be readily understood that by altering the scales or receptacles W, W,
together with the plugs K', the machine can be easily adapted for weighing solids.
It is to be understood that we do not confine ourselves to the exact arrangement
hereinbefore described, as the parts may, manifestly, be altered without departing
from the principle of the invention.
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed, we declare that what
we claim is :-
:-
1. An automatic weighing machine, having filling scales (W, W,), which are
alternately charged with material (the amount of the charge being regulated by
means of travelling weights G. and sliding stops h, h¹) from efflux tubes (R, R¹),
provided with cocks (0, 0¹) the cocks being alternately opened by the oscillations
of the machine and closed by the action of a two-armed tumbling lever (E), the

page_text: scales being emptied by knocking up a plug (K'), fitted in the bottom of each,
substantially as hereinbfore described with reference to the drawings annexed.
2. In a machine of the class herein before set forth, the combination therewith
of a bar (S) with movable weights, for the purpose of enabling the machine to be
used for weighing different quantities in each scale, substantially as hercinbefore
described.
3. The general arrangement and combination of parts of the improved weighing
machine, substantially as hereinbefore described and shown on the drawings
annexed.
Deted this 22nd day of La1802
H. D. FITZPATRICK,
70, Wellington Street, Glasgow, Agent.