Improvements in Coin-freed Weighing Machines.
Year: 1892

page_text: Date of Application, 4th Aug., 1892-Accepted, 10th Sept., 1892
COMPLETE SPECIFICATION.
Improvements in Coin-freed Weighing Machines.
I, GRAYDON POORE, of 35, Oakhill Road, Putney, in the County of Surrey,
Civil 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:-
"3
This invention relates to that class of weighing machines known as "automatic
and in which the weight of the person or article placed on the platform is not
indicated on the dial until the mechanism or some part of it, has been released by
the insertion of a coin of predetermined size or weight and has for its object the
simplification of the mechanism employed so as to ensure certainty of action, and
to arrange the said mechanism that it can readily be applied to existing non-
"automatic" weighing machines and so convert them to "automatic" machines.
Automatic weighing machines can be divided into two classes:
1st. Those in which the body placed on the platform is immediately weighed but
the weight is not indicated until after the insertion of the coin as in Everitt's
Patent No. 16,433 of 1884, or the indication is not rendered visible as in Cooper's
Patent No. 5139 of 1886, and in Reimann's Patent No. 10383 of 1886.
2nd. Those in which the machine is normally locked and the platform prevented
from falling by the action of a stop so arranged that it can be released and removed
by the coin, or released by the coin and removed by the hand as in Knight's Patent
No. 15,580 of 1886, and in Salter's Patent No. 6983 of 1886.
Machines constructed according to my invention are included under the second
of these classes, and in carrying my invention into effect I provide a stop consisting
of a pair of "toggle" links, one end of which is connected to or engages with
the framing of the machine and the other engages with any convenient moving
part of the weighing mechanism such as the rod connecting the weighing plat-
form and levers with the indicating gear. I so arrange these toggle links that
they shall sustain the load on the platform when their centres are in the same
straight line or nearly so, as they then practically form one continuous column or
strut. When in this position a very small force, acting at their point of connec-
tion to each other aud in a direction at right angles to their common centre
line will suffice to remove them out of the straight line, when they will cease to
form a strut and the weight on the platform in descending will carry them down
before it.
The force necessary for this purpose is provided by the weight of the coin,
which, on insertion into the machine, is allowed to fall into a suitable receiver
or coin bucket. This coin bucket is fixed at one end of a lever carried on centres
fixed to the framing of the machine and is provided with a suitable counter balance
weight.
The coin bucket is provided with a hinged bottom actuated by a pin attached
to the bucket in such a manner that it is free to move in an upward direction,
but when depressed, it first engages with the bottom of the bucket, or a pin thereon,
and then moves it aside. One or more projections on the framing of the machine
are arranged to engage with this bucket pin. During the descent of the bucket
lever by the action of the coin, the pin is merely lifted by and allowed to pass
over them, but on the lever being raised it engages with one of them, moves the

page_text: bottom aside and allows the coin to fall into a receptacle provided for the
purpose. The balance weight will then replace the bucket lever in its normal
position.
An arm projecting from the bucket lever engages with a pin on the centre of
the toggle links by means of a hooked rod and so enables the weight of the coin
during the descent of the bucket lever to pull them out of the "straight line"
position.
The toggles are then free to fall, the platform is free to descend and the weight
will be indicated on the dial in the usual manner.
After the operation, the platform is raised by the main springs and the toggles
are replaced in their normal "straight line" position and the bucket lever is also
replaced by the same action. This in turn discharges the coin in the manner
indicated above and the machine is once more locked.
I will now describe my invention more fully by reference to the accompanying
drawings, which represent an apparatus suitable for attachment to an ordinary
"Salters" spring weighing machine.
Fig. 1. is a front elevation of the apparatus, the front of the casing and the
projecting toggle centre-pin being removed so as to show the mechanism. I have
indicated the weighing machine to which it is intended to be attached, by dotted
lines.
Fig. 2. is a side elevation in section showing the attachment of the toggles to
the framing and weighing rod, the coin gear being omitted for clearness. The
Figures 1 and 2 shew by dotted lines the upper portion of a spring weighing
machine consisting of a casing A. A, main springs B B, column C which is hollow
and fixed to its lower end on the casing which carries the weighing platform.
Through C runs a rod D, which is attached at its lower end to the lever on which
the platform rests and at its upper, to the crosshead E which is hung on the
springs B, and operates the indicating gear by means of the rack G, the pinion F,
the pointer H, and the graduated dial I. All this is of the usual well-known type
and requires no further description.
KK is a casing arranged to carry the automatic mechanism. It fits over the
original casing AA of the weighing machine and is fixed to it by bolts K' K'.
LL is a cover or front which is removable to allow of the gear being examined and
carries in its centre a glass plate M, through which the dial I and the pointer H
can be seen.
N, O are a pair of toggle links which form a stop and lock the machine when
their centres are in or approximately in the same straight line. They pass through
and work in an aperture A' in the casing A. and are centred and carried at the
lower end of O by a pin projecting from a bracket or bridge-piece P, and at the
upper end of N are connected to the crosshead E and rod D of the weighing machine
by the pin R (see Fig. 2). Their common centre pin S projects forward as shewn
in Fig. 2 as and for the purpose hereinafter set forth.
T is a lever which carries at one end the coin bucket U. and at the other
the balance weight V. It is centred at W to the bracket W₁ which is fixed to the
casing K. The coin is directed to the bucket U by a shoot from an external slot
in any suitable manner.
An arm T which projects in a downward direction from the bucket lever T is
connected to the centre pin S (Fig. 2) of the toggles N, O, by means of a rod T*
provided with two lugs T and T. Y is a pin fixed in the casing K K which serves
as a guide to the rod T which slides on it.
The coin bucket U normally lies below the shoot from the money slot and is
fitted with a hinged bottom U¹ having a projection U³. The pin U is free to
lift when pushed upwards, turning on the same centre as the hinged bottom piece U...
When pushed in a downward direction it engages with the projection U³ and causes
the hinged bottom to lift up and allow the contents of the bucket to fall out into Z
which is a receptacle provided for them. X X represent a row of projections
on the casing K K over which the pin U rides inoperatively during the downward

page_text: travel of the bucket U but engages with one of them and so raises the bottom U¹‍
when the bucket is ascending.
The toggle links NO are shewn with their centres in the same straight line.
This is a position of very unstable equilibrium and I prefer to allow them when
at rest to lean against the stop P' carried from the bridge piece P and which
allows the centre pin S to be a little out of the straight line and on the same,
side of it as the coin bucket. U. This makes the links lock the machine more
securely.
The action of the mechanism is as follows:
When a weight of any kind is placed on the platform of the machine it tends to
pull down the crosshead E by means of the platform levers and the rod D. This
however is prevented from moving in a downward direction by the toggle links.NO.
which form a strut under it.
If a coin be now inserted in the machine it falls into the bucket U and by its
weight carries it down together with the bucket lever T. The arm T₁ and
hooked rod T then exert a pull on the centre pin S of the toggle links, by bringing
the lug T against it.
This has the effect of putting the toggle links NO out of their straight line
position and the weight on the platform acting through the rod D and crosshead E
carries them down easily to the position shown by broken lines and the weight is
indicated by the pointer H on the dial I in the usual manner, the pointer H being
driven by the pinion F and the rack G. The guide pin Y prevents the rod T' from
resting on the toggles during the process of weighing.
When the weight is taken off the platform, the springs B B pull up the cross-
head E and draw the toggles N O into the straight line position and their centre
pin S, as it rises, catches the lug T' and by means of the rod T2 and the levers T
and T raises the bucket U to its normal position, the coin being released and
allowed to fall into the receptacle Z as the pin U engaging with one of the
projections X is pressed downwards and so lifts the hinged part U₁ of the bucket
by coming into contact with U.
The balance weight V then presses the lug T* against the centre pin S (through
the lever T and the rod T2) and pushes the toggle links against the stop P2 and
slightly out of the straight line position.
The hinged bottom U' of the coin bucket U is so balanced that it falls back
into its normal position as soon as the pin Us is clear of the stops X so the
whole apparatus is now in the same position as when operations were started and
cannot be used again without the insertion of another coin.
I have described the apparatus as applied to a spring balance weighing machine,
but it is obvious that it is equally applicable to any other kind.
I have also described the toggle stop as being removed by the weight of the
coin, but I can also effect this by the operator acting in conjunction with the coin;
the hand gear being previously freed by the action of the coin in any usual manner
and the rest of the action being performed by the hand of the operator actuating
a rod adapted to displace the toggle links.
I find it sometimes convenient to use a dash-pot in the known manner to
avoid shocks to the machinery when the toggle stop falls and suddenly releases the
platform.
I also sometimes find it convenient to use a revolving dial and fixed pointer
instead of a fixed dial and revolving pointer as described above.
Having now thus fully described my invention and in what manner it may
conveniently be carried into effect, I hereby declare that I make no claim to any
part of the weighing mechanism, nor do lay claim to any special form of coin
gear. But what I do claim is :-
}
1st. A coin freed weighing machine having all its moving parts normally held
fast, but adapted to be released and rendered operative by the action of a coin the
machine being constructed substantially as and in the manner described.

page_text: 2nd. In weighing machines which are normally locked and intended to be released
on the insertion of a coin, the arrangement of locking gear consisting of a pair of
toggles which, when in the same straight line, support the load on the plat-
form, but can be thrust aside and so release it by or after the insertion of a coin.
3rd. The hereinbefore described arrangement of toggles N, O, counterweighted
coin bucket lever T with arm T¹ and hooked rod T engaging toggle pin S
combination with the weighing rod D of a spring balance weighing machine, t
whole being arranged and adapted to operate substantially in the manner and f
the purpose set forth.
4th. The hereinbefore described arrangement of appliances for converting
-ordinary spring balance weighing machine into a coin freed one substantially as st
forth.