Improvements in Spring Actuated Weighing Machines.
Year: 1898

page_text: Date of Application, 6th Sept., 1898-Accepted, 13th May, 1899
COMPLETE SPECIFICATION.
Improvements in Spring Actuated Weighing Machines.
I, PAUL JOHANN STEINKE, of 43, Waldstrasse, Berlin, in the German Empire,
Mechanical Engineer, 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:-
The invention, forming the subject of the present application, refers to spring
balances, in connection with which the weight suspended from the arm of a lever
tightens a spring, in the well known manner, and in consequence of the spiral
spring being compressed, the weight of the object to be weighed is indicated on
a scale graduated empirically, by means of a pointer which is connected with the
scale-beam.
The spring balances hitherto known shew this great defect, that the spring is
subject to variations of volume, in consequence of variations in temperature, so
that the indicator no longer points exactly to the zero position; and moreover,
the fractional weights cannot be read off from the scales with precision.
The present invention has done away with this defect, as it is possible, not only
to adjust the scales without any difficulty, but, moreover, to indicate the most
precise fraction of the weight, by means of the mechanism described.
The invention is illustrated in the annexed drawings, in which Figure 1 is a
front elevation of the scales: Figure 2 is a side view; and Figure 3 a detai!.
On the bottom plate b, which is adjustable by means of thumb-screws a, is a
column e, which carries the entire weighing mechanism, which may be provided
with some well known plumb appliance d, for the purpose of checking the
vertical adjustment of the apparatus. This column c, at its top, carries the forked
support e, in which a shaft is placed between ball bearings f f¹. This shaft g,
which may suitably be held in the support e, by means of the ball bearing screw .
is enclosed in a casing i, upon which there is a cog wheel k. This casing & rests
between the side of the support e and the protuberance of a casing n, soldered
to the counter-nut m of the screw h. To the casing of the cog wheel k, the inner
end of the spiral spring o is fastened, and the other end of the spring is made
fast to the scale-beam p which is firmly attached to the shaft g. This scale beau
at its outer end carries the weighing scale q, whilst the indicator r is firmly, con-
nected with the scale beam and the shaft g.
The indicator moves about a scale arranged on the column e, and which is
graduated empirically.
is
Into the cog wheel gears a pinion s, which can be actuated by means of the
hand wheel. Upon a sleeve on the shaft of the pinion s an indicator
arranged, which is held in position solely by friction, and can be turned by hand,
without thereby affecting the pinion s. The indicator moves in front of an
upper scale r, which has likewise been graduated empirically, and its object is
to indicate the exact fractions of the weight.
The operation of the mechanism is as follows:
Assuming the weight of the article to be weighed to be 5.45 grammes, when

page_text: the article is placed upon the weighing scale 4, the indicating pointer r will move
to a point intermediate 5 and 6 grammes, on the scale u. The indicator v, on
the scale, is now placed against the Figure 5, by hand, and the button t is then
turned, until by reason of the revolving motion given to the cog-wheel, and
the consequent tension of the spring o situate on the casing of the cog wheel k,
the scale-beam, and with it the indicator r, are so far raised, that the pointer
on the lower scale u points to the Figure 5. The indicator v will then point to
5.45 on the upper scale, so that the precise fractional weight may be read off the
upper scale w
The balance may also be used in the reverse manner, for weighing off a certain
quantity of any substance. For this purpose, and in this case (for example), the
indicator is pointed to 5 grammes, by hand, without actuating the button_t,
and then turned to 5.45, by means of the button t, whereupon so much of the
material to be weighed off is dropped into the weighing scale q, as will make the
indicator on the lower scale u indicate 5 grammes. In order to compensate for
the influence of changes of the temperature, if, by reason of a change of tempera-
ture, the indicator on the lower scale does not point exactly to the zero position,
it is placed precisely against zero, by means of turning backward or forward the
button the indicator being then brought back by hand to the zero of the
upper scale w.
Having now particularly described and ascertained the nature of this inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is:
1. A spring actuated weighing machine wherein the scale beam when loaded,
is caused to move a hand in connection therewith out of its normal position, and
a second scale with a rotatable loosely mounted hand for ascertaining the exact
fractional weight, so adapted as to cause the action of the spiral spring influenced
by the weight on the scale beam to be reversed on turning such hand, and so that
when the hand, moving along the main scale, assumes a position, as described,
the second hand will indicate the exact weight on the second scale; subsian-
tially as set forth.
2. In a spring actuated weighing machine, the combination of the main or
essential parts, as set forth with reference to and shewn in the drawings.
3. In weighing machines, of the type herein described, the arrangement and
combination of a spiral spring o; a shaft g, to which it is connected, mounted in
suitable bearings; and a pointer r, connected with the weigh beam; as set forth
with reference to and shewn in the drawings.
Dated this 5th day of Santonia 1900
CHEESBROUGH & ROYSTON,
Applicant's Patent Agents, 15, Water Street, Liverpool.