Improvements in Weighing Scales.
Year: 1889

page_text: Date of Application, 20th Aug., 1889
Complete Specification Left, 20th May, 1890-Accepted, 16th Aug., 1890
PROVISIONAL SPECIFICATION.
Improvements in Weighing Scales.
I, ROBERT EMETT GLOVER, of Granger in the County of Scotland, State of Missouri,
United States of America, Gentleman, do hereby declare the nature of this invention
to be as follows:-
My invention relates to improvements in scales for weighing drugs and other
articles in small quantities.
In one form of this invention a quadrant shaped table or base is provided at its
corners with depending legs or supports and on said table, near the inner corners
thereof are a pair of bearings. A fulcrum plate is arranged between the said bearings
and has a pair of upturned ears at its corners through which extend pivotal pins
that project from the inner side of the bearing blocks.
A scale arm is pivoted on the centre of the plate at a point beyond the axis thereof
by means of a pin or stud and on the shorter end of the said arm is attached a
weight while the outer end of the arm is adapted to sweep over a graduated scale on
the face of the table near the curved edge thereof the said arm supporting the scale
pan. The weight is sufficiently heavy to just balance the empty scale pan when the
arm is at exactly right angles to the fulcrum plate.
An adjusting arm is pivoted to the fulcrum plate and carries a second weight and
the vertical inner end of the said arm is provided with a thumb-nut by means of
which said adjusting arm may be rotated and thus cause the weight to be extended
to any desired distance from the fulcrum plate.
The operation of this construction is as follows:-
When the principal arm vibrates from its normal position at right angles to the
fulcrum plate and from the zero mark on the scale the centre of gravity moves back
from the fulcrum of the arm to the weighted end thereof and the figures on the dial
under the arm when the latter is brought to rest indicate the weight of material
necessary to balance the arm; thus if it is desired to weigh two scruples of a com-
modity the arm is turned until its outer end is over the appropriate mark on the
dial and it will then require exactly two scruples of the commodity when placed in
the pan to balance the arm.
The function of the adjustable arm is to compensate for any imperfection in the
construction of the mechanism and to enable the scale-arm or principal arm to be
balanced with a paper or other substance on the pan, the weight of the paper not
being a part of the commodity placed in the pan and this is readily accomplished by
turning the thumb-nut in such manner as to adjust the second weight, the arm being
slotted for that purpose, to the necessary distance from the fulcrum plate.
I will now describe a modification.
The base in this form of apparatus may be of quadrant shape, or it may have any
other preferred shape, said base being provided along its front curved edge with a
strip having upon its upper face a graduated scale. Supported upon and adapted to
be secured to the base in any suitable manner is a table or platform of a shape
corresponding to that of the base, a uarrow opening being left between the front edge
of said table and the rear edge of strip.
Upon the table near its rear end is secured a metallic strip the upper edge of
which is sharp whereby to serve as a knife edge bearing for a ring provided with
notches for the reception of said edge; said ring serves the same purpose as, and
operates in a manner similar to, the plate in the form first above described.
The
The scale arm in the modification may be a single arm, or it may consist of two
sections united by cross pieces the whole forming practically a single arm.
rear ends of the sections are secured to a weight which may be made annular and

page_text: has an eccentrically located socket or recess upon its underside. To the forward
ends of the sections are secured arms adapted to support a scale pan while of said
sections is curved downward and plays over the scale.
The weight is supported upon the upper edge of the ring and upon said edge it is
adapted to turn freely when the scale arm is shifted in its position. When the
weight is placed in position the heavier portion lies in rear of the pivotal axis of
ring as in the construction first described and said weight is so arranged relatively
to the scale arm that it will exactly counterbalance the combined weight of the latter
and the scale pan when said arm points to the zero mark the latter being say about
20° to one side of a line perpendicular to the pivotal axis of ring instead of at right
angles to said axis as in the first construction.
To steady the scale arm when being shifted a rod is provided the forward end of
which is hooked to a loop on the lower end of a vertical arm secured to the scale
arm and likewise hooked at its rear end to a loop or staple on the underside of the
platform.
To provide a means for compensating for any imperfection in the construction of
the mechanism and to balance the scale arm when paper or other substance is placed
in the scale pan I employ a rod carrying at its forward end a weight said rod passing
through openings in the cross pieces of the scale arm and adapted to be adjusted
horizontally therein to carry the weight closer to or farther from the fulcrum of the
ring. Or instead of this arrangement the rod may be made stationary and the weight
made to travel thereon, or any other preferred arrangement may be adopted whereby
to secure the desired result.
The operation of this construction of my device is similar to that of the construction
first described.
BERNHARD DUKES,
226, High Holborn, London, W.C., Agent for the Applicant.
COMPLETE SPECIFICATION.
Improvements in Weighing Scales.
I ROBERT EMETT GLOVER of Granger in the County of Scotland, State of Missouri
United States of America Gentleman, 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:—
My invention relates to an improvement in scales for weighing drugs and other
articles in small quantities and it consists in the peculiar construction and combination of
parts that will be more fully set forth hereinafter and particularly pointed out in the
claims.
In the accompanying drawings
Fig. 1 is a perspective view of a scales embodying my improvement.
Fig. 2 is a sectional view of the same.
Fig. 3 is a plan view of a modified construction of my scales the counterbalancing
weight being in section and
Fig. 4 a vertical section thereof.
Although I have shown in the above drawings, two constructions of my improved
device, yet the principle of operation is the same in each of said constructions.
I will first describe that construction shown in Figs. 1 and 2, and in these figures,
the quadrant shaped table or base A is provided at its corners with depending legs or
supports B and on said table, near the inner corners thereof are a pair of bearings C.
A fulcrum plate D is arranged between the said bearings and has a pair of upturned
ears E at its corners through which extend pivotal pins F that project from the inner
side of the bearing blocks.
A scale arm G is pivoted on the centre of the plate D at a point beyond the axis
thereof by means of a pin or stud B and on the shorter end of the said arm is attached

page_text: a weight I, while the outer end of the arm is adapted to sweep over a graduated
scale K on the face of the table near the curved edge thereof, the said arm supporting
the scale pan L.
The weight I is sufficiently heavy to just balance the empty scale pan when the arm G
is at exactly right angles to the fulcrum plate.
An adjusting arm M is pivoted to the fulcrum plate and carries a weight N and
the vertical inner end of the said arm is provided with a thumb-nut O by means of
which said arm may be rotated and thus cause the weight to be extended to any
desired distance from the fulcrum plate.
The operation of this construction is as follows:
When the arm G vibrates from its normal position at right angles to the fulcrum
plate and from the zero mark on the scale, the center of gravity moves back from the
fulcrum of the arm G to the weighted end thereof and the figures on the dial under
the arm G when the latter is brought to rest indicate the weight of material
necessary to balance the arm G; thus if it is desired to weigh two scruples of a
commodity the arm G is turned until its outer end is over the appropriate mark on
the dial and it will then require exactly two scruples of the cominodity when placed
in the pan to balance the arm.
The function of the adjustable arm M is to compensate for any imperfection in the
construction of the mechanism and to enable the scale arm G to be balanced with a
paper or other substance on the pan, the weight of the paper not being a part of the
commodity placed in the pan and this is readily accomplished by turning the thumb
nut O in such manner as to adjust the weight N, the arm M being slotted for that
purpose, to the necessary distance from the fulcrum plate.
I will now describe the construction illustrated in Figs. 3 and 4, and in these
figures, A¹ indicates the base which may have the quadrant shape shown or it may have
any other preferred shape, said base being provided along its front curved edge with
the strip a having upon its upper face a graduated scale K¹. Supported upon and
adapted to be secured to the base A¹ in any suitable manner is a table or platform A²,
of a shape corresponding to that of the base A¹, a narrow opening a¹ being left between
the front edge of said table and the rear edge of strip a.
Upon the table A² near its rear end is secured a metallic strip ( the upper edge
of which is sharp, whereby to serve as a knife-edge bearing for a ring D' which is
provided with notches d for the reception of said edge as shown, said ring D¹ serving
the same purpose as and operating in a manner similar to the plate D in the con-
struction first described.
G¹ is the scale arm which may be a single arm as in the other construction or it
may consist of two sections g as shown united by the cross-pieces g¹ the whole forming
practically a single arm. The rear ends of the sections g are secured to a weight I¹
which in this instance is made annular and having an eccentrically located socket or
recess upon its underside. To the forward ends of the sections g are secured arms
which are adapted to support a scale pan while one of said sections is curved
downward and plays over the scale.
As shown the weight I is supported upon the upper edge of the ring D¹ upon
which edge it is adapted to freely turn when the scale arm is shifted in its position.
It will be seen that when the weight is placed in position the heavier portion lies
in rear of the pivotal axis of ring D₁ precisely as in the construction first described
and said weight is so arranged relatively to the scale arm that it will exactly
counterbalance the combined weight of the latter and the scale pan when said arm
points to the zero mark the latter being in this instance about 20° to one side of a line
perpendicular to the pivotal axis of ring D' as shown, instead of at right angles
to said axis as in the first construction.
To steady the scale arm when being shifted, a rod i¹ is provided the forward end
of which is hooked to a loop on the lower end of the vertical arm i³ secured to the
scale arm and likewise hooked at its rear end to a loop or staple on the underside of
the platform.
To provide a means for compensating for any imperfection in the construction of

page_text: the mechanism and to balance the scale arm when paper or other substance is placed
in the scale pan I employ a rod M' carrying at its forward end a weight N¹ said rod
passing through openings in the cross pieces of the scale arm and adapted to be
adjusted horizontally therein to carry the weight closer to or farther from the fulcrum
of the ring D¹. Or instead of this arrangement the rod M¹ may be made stationary
and the weight ma le to travel thereon, or any other preferred arrangement may be
adopted whereby to secure the desired result.
The operation of this construction of my device is similar to that of the construction
first described and need therefore, not be given in detail.
It will be seen that when the scale arm is shifted in its position the weight
will be shifted in its position, thereby changing its position relatively to the
fulcrum of the ring D in a manner similar to the weight I, whereby the quantity of
material placed in the scale pan to balance the arm will vary according to the
distance the arm is moved away from the zero mark.
It is obvious that no weights or springs are necessary as a part of the scales,
other than the counterbalancing weight and the adjusting weight and that the scales
are adapted to weigh small commodities with very great accuracy and with great
rapidity.
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 :-
1. In a scales, the combination with a fulcrumed support, of a scale arm supported
thereby and adapted to be turned relatively thereto, said scale arm being provided at
its rear end with a counter balancing weight, and adapted to carry at its forward end
a scale pan as described.
2. In a scales, the combination with the base having the graduated scale K³, and
the table or platform supported upon said base, of the strip C secured upon said table,
the ring D fulcrumed upon the upper edge of said strip, the weight 1 having the
recess and supported and adapted to be turned upon said ring, and a scale arm secured
at its rear end to said weight and its forward end adapted to play over the scale and
to support a scale pan as described.
3. In a scales, the combination with the base having the graduated scale K' and
the table or platform supported upon said base, of the strip C¹ secured upon said
platform, the ring D' fulcrumed upon the upper edge of said strip the weight I' having
the recess, and supported upon said ring, a scale arm secured at its rear end to said
weight and its forward end adapted to play over the scale and to support a scale pan,
and a second weight supported by said scale arm and adapted to be adjusted longitudi-
nally thereon, for the purposes specified.
Dated this 20th day of May 1890.
JENSEN & SON,
77, Chancery Lane, London, W.C., Patent Agents.