Improvements in Weighing Apparatus.
Year: 1896

page_text: Date of Application, 9th Jan., 1896-Accepted, 15th Feb., 1896
COMPLETE SPECIFICATION.
Improvements in Weighing Apparatus.
I, ALPHA REEVE BEAL, of the Town of East Bloomfield, in the County of
Ontario and State of New York, United States of America, Commercial Agent,
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 improvement relates to platform-scales; and it consists in the combination
and arrangement of parts hereinafter more fully described and embodied in the
claims.
In the drawings,
Figure 1 is a front elevation of a platform-scale, showing my invention.
Fig. 2 is a plan view of the carriage looking down from line 1-1 of Fig. 1.
Fig. 3 is an enlarged cross-section of the carriage and frame in line 2-2 of
Fig. 2.
Fig. 4 is an enlarged cross-section in line 3-3 of Fig, 1, showing more
particularly the means for locking the price-poise in position while the carriage
is being shifted.
Fig. 5 is a vertical section in line 4-4 of Fig. 4.
Fig. 6 is a diagram showing one of the locking pins and the slides that work
therein.
Fig. 7 is a cross-section in line 5-5 of Fig. 1.
A indicates the platform, which is of ordinary construction.
B is the main frame supported by the platform, and C is the carriage which
moves forward and back on the frame, being provided with friction-wheels a a to
lessen friction.
D is a standard rising from the carriage and serving as the fulcrum for the
lever-work. In the example shown in the drawings the apparatus is of the kind
known as a "price or computing scale," in which when a weight is placed on the
platform and the price-poise has been adjusted to a given price per pound the
aggregate value is indicated by a sliding poise on another beam. I do not, however,
limit my invention to this particular class of scales.
E, F, and G are three scale beams, all combined together and turning on the
fulcrum D. The lower beam E has a scale from 3 up to 60, more or less, which
indicates price per pound, and in connection with this is used a price-poise H,
which has no longitudinal movement, but the adjustment in changing from one price
to another is accomplished by sliding the beam through the poise by moving the
carriage. The upper beam F has a single scale from 1 upward and the middle
beam G has two scales each from 1 upward. The bottom scale of the middle
beam G indicates pounds when the price-poise is set at 10, and the upper scale
of said middle beam and the single scale of the upper beam F both indicate
aggregate values of any weight at any given price per pound by moving a counter-
poise I, so as to balance the beams under the weight on the platform. This
arrangement is the same as in other price-scales in use.
J is another beam, having its fulcrum at 6 on the under side of the frame and
loosely connected with the beam E by a rod connection c. This beam is provided
with a scale and constitutes a tare-beam, and is used for indicating pounds-weight
on the platform.
The beam E slides loosely through the slot of the price-poise H, and it has been

page_text: found difficult to adjust the pointer accurately to the number on the scale by hand
without taking too much time.
If the price-poise is set accurately by making it drop into notches, on the beam,
and the carriage is locked when the tooth on the price-poise drops into the notches,
the draw-bar is put out of line by the setting of the price-poise unless it is set so
that the tooth drops squarely into the notches without any sliding motion of the
price-poise whatever. This throwing of the draw-bar out of line interferes with
and destroys the accurate weighing qualities of the scale. I remedy these
difficulties by the following means:-
To the carriage is attached a longitudinal rack K, provided with teeth spaced
to correspond with the sub-divisions of the scale, and to the main frame is pivoted
at fa pawl L, capable of being thrown into and out of engagement with the rack.
The teeth of the rack and the end of the pawl are wedge-shaped, and when the
scale-beam is adjusted through the poise so as to bring the desired number approxi-
mately to the pointer of the poise, if there is any discrepancy in the adjustment the
pawl, striking down into the rack, will draw the beam exactly to place. If desired
the arrangement may be reversed, the rack being attached to the frame and the
paul to the carriage.
By the means above described both edges of the scale-beam E can be made
smooth and unnotched, insuring easy movement of the beam through the poise and
obviating many difficulties where the edge of the beam is notched.
M is a longitudinal shaft attached to the carriage C and provided with a
handle h at one end, by which it is turned, and a tension-spring i at the other,
which tends to hold it in position. On this shaft is a cam k, resting in a half-
circular camway 1 of the pawl and striking a lug m of the pawl to throw the latter
up when the shaft is turned against the spring. The rear part of the camway is
notched as shown at ', by which means the pawl makes a quick movement at the
first turn of the shaft in order to engage with the rack. When once adjusted to
a given number on the scale-beam the price-poise H must be locked to the beam to
prevent displacement, but in order to move the beam through the poise it must be
unlocked again. The arrangement for locking and unlocking is shown in Figs. 4, 5,
and 6 In the upper end of the poise H is mounted a gib or washer N, which is
movable up and down and fits the under side of the scale-beam, a packing n
being interposed between them. This gib is provided with two pins o o, which
rest locsely in sockets in the poise and it is pressed up by springs p p around the
pins. The pins are provided with cross-slots rr, in which enter the ends of
slides ss from opposite sides of the poise, the ends of the slides being wedge-
shaped and lapping past each other, as shown in the cross-section, Fig. 6.
the slides are forced inward the gib is depressed, thus relieving it from contact
with the edge of the beam. The slides are hrown out by coiled springs t t.
When
When
P is a clamp consisting of two arins pivoted together at q, like a pair of shears,
said aims extending up on opposite sides of the poise H and there provided with
two branches u u, with heads that come opposite the ends of the slides s 8.
the arms are compressed, the heads force the slides inward and release the gib
from the scale-beain, as before described. The clamp is operated by a wedge,
which rests between pins w w on the lower ends of the arms of the clamp. The
wedge is attached to a crank-arm r, which in turn is attached to the shaft M and is
thrown by it.
In order to level the scale-beam and hold it so that it can be run freely through
the poise, I employ a locking device, as follows:-
R, Figs. 1 and 7, is a rod that moves freely up and down in bearings of the
carriage, its upper end resting in line with the scale-beam E, but out of contact
therewith. It is forced down to a stop by a spring y, and it is raised against the
spring by crank arm on the shatt M. The action of turning the shaft to release
the pawl raises the rod.
jis a yoke embracing the scale-beam and pivoted centrally to a bearing e of the
carriage.

page_text: a a are stops on the yoke which strike the edges of the scale-beam. The lower
end of the yoke is jointed to the upper end of rod R, and when the latter is thrown
it raises the scale-beam to a level position and the yoke clamps upon both edges
and holds it firmly in place.
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 weighing scale, the combination of a bed plate, a carriage movable
forward and backward thereon, a scale-beam attached to the carriage and provided
with a scale, a poise through which the scale-beam slides, a rack whose teeth are
wedge-shaped and spaced to accord with the divisions of the scale on the beam, a
pawl engaging with the rack, and means for operating the pawl, the whole so
arranged, as described, that the engagement of the pawl with the teeth of the rack
will move the carriage and adjust the divisions of the scale accurately with the
poise as specified.
2. In a weighing scale, the combination of a bed plate, a carriage movable
forward and back thereon, a scale-beam provided with a scale attached to the
carriage, a poise through which the scale-beam slides, a rack whose teeth are
wedge-shaped and spaced to accord with the divisions of the scale on the beam, a
pawl engaging with the rack, a cam and shaft for operating the pawl, a locking
attachment connected with the poise, and means for operating the locking attach-
ment, the whole so arranged, as described, that the engagement of the pawl with
the rack will move the carriage and adjust the divisions of the scale accurately
with the poise, and the poise will then be locked to the scale beam, as specified.
3. In a weighing scale, the combination of a movable carriage, scale beam
pivoted thereto so as to move with the carriage, a poise through which the scale
beam slides, a gib connected with the poise, provided with slotted pins, slides with
wedge-shaped ends entering the slots of the pins, a clamp operating on the slides,
and means for actuating the clamp, as specified.
4. In a weighing scale, the combination of a movable carriage, a scale beam
pivoted thereto, a sliding rod resting under the scale beam, a yoke embracing the
scale beam, said yoke jointed to the end of the sliding rod, and means for operating
the sliding rod, as specified.
Dated this 9th day of January 1896.
ALLISON BROS.,
Agents for the Applicant.