IMPROVEMENTS IN WEIGHING MACHINES
Year: 1871

page_text: LETTERS PATENT to James Murdoch Napier, of York Road, Lambeth,
in the County of Surrey, for the Invention of "IMPROVEMENTS IN
WEIGHING MACHINES."
Sealed the 15th September 1871, and dated the 30th June 1871.
PROVISIONAL SPECIFICATION left by the said James Murdoch Napier
at the Office of the Commissioners of Patents, with his Petition,
on the 30th June 1871.
I, JAMES MURDOCH NAPIER, of York Road, Lambeth, in the County
of Surrey, do hereby declare the nature of the said Invention for "IM.
PROVEMENTS IN WEIGHING MACHINES," to be as follows:-
This Invention has for its object improvements in weighing machines,
and refers to machines for weighing and classifying according to their
weights the articles or things weighed, such as coins and coin blanks.
The machines may be furnished with the usual hopper or reservoir and
feeding slide, which for convenience in carrying out a compact and
simple arrangement of the mechanism I place by preference at a right
angle to the line of the weighing beam, and actuate by a cam groove

page_text: formed on a cylinder, and which is connected through a lever with the
feeding slide. While the coin is being placed on the weighing plate
grippers may be used in the ordinary way to hold it steady. After the
coin is placed the grippers are opened rapidly (by a cam connected with
them) in such manner that the beam is at once set free to dip at one
end or the other according to the preponderance of the load or of the
counterpoise. This action of the beam brings it or a part connected
with it into contact with an electrical conductor and completes a circuit,
so that an electro-magnet becomes charged; this operates through its
armature and connections upon a directing edge or directing tube to
place it in a position so as to cause the offcoming coin after it has been
weighed to pass into one of several receptacles for classification. When
desired the ordinary remedy weights may be used to keep the beam from
vibrating until the difference between the load and the counterpoise
exceeds a given limit.. I combine and actuate the levelling apparatus
for bringing the beam back to its horizontal position so that it operates
to level the beam after weighing and just previous to the grippers being
closed, and that it ceases to operate and leaves the beam and its
appendages free before the grippers open, so that when they do open the
beam may be at once free to be acted upon by any preponderating
weight.
In the coin classifying machines at present in use the levelling
apparatus finally releases the beam for weighing, whereas it will be
understood from what is stated above that in my improved classifying
machines I use the grippers finally to release the beam and leave it free
to vibrate.

page_text: fifth year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said James Murdoch Napier, Her special license
that I, the said James Murdoch Napier, my executors, administrators,
and assigns, or such others as I, the said James Murdoch Napier, my
executors, administrators, and assigns, should at any time agree with,
and no others, from time to time and at all times thereafter during the
term therein expressed, should and lawfully might make, use, exercise,
and vend, within the United Kingdom of Great Britain and Ireland, the
Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN
WEIGHING MACHINES," upon the condition (amongst others) that I, the
said James Murdoch Napier, my executors or administrators, by an
instrument in writing under my, or their, or one of their hands and
seals, should particularly describe and ascertain the nature of the said
Invention, and in what manner the same was to be performed, and
cause the same to be filed in the Great Seal Patent Office within six
calendar months next and immediately after the date of the said Letters
Patent.
NOW KNOW YE, that I, the said James Murdoch Napier, do hereby
declare the nature of the said Invention, and in what manner the same
is to be performed, to be particularly described and ascertained in and
by the following statement thereof, that is to say :-
This Invention has for its object improvements in weighing machines,
and refers to machines for weighing and classifying according to their
weights the articles or things weighed, such as coin and coin blanks.
The machines may be furnished with the usual hopper or reservoir and
feeding slide, which for convenience in carrying out a compact and simple
arrangement of the mechanism, I place by preference at a right angle
to the line of the weighing beam, and actuate by a cam groove formed
on a cylinder, and which is connected through a lever with the feeding
slide. While the coin is being placed on the weighing plate grippers
may be used in the ordinary way to hold it steady. After the coin is
placed the grippers are opened rapidly (by a cam connected with them)
in such manner that the beam is at once set free to dip at one end or
the other according to the preponderance of the load or of the counter-
poise. This action of the beam brings it or a part connected with it
into contact with an electrical conductor and completes a circuit, so
that an electro-magnet becomes charged. This operates through its
armature and connections upon a directing edge or directing tube to

page_text: place it in a position so as to cause the off-coming coin after it has
been weighed to pass into one of several receptacles for classifi-
cation. When desired the ordinary remedy weights may be used to
keep the beam from vibrating until the difference between the load
and the counterpoise exceeds a given limit. I combine and actuate
the levelling apparatus for bringing the beam back to its horizontal
position so that it operates to level the beam after weighing, and just
previous to the grippers being closed, and that it ceases to operate
and leaves the beam and its appendages free before the grippers open,
so that when they do open the beam may be at once free to be acted
upon by any preponderating weight.
In the coin classifying machines at present in use the levelling
apparatus finally releases the beam for weighing after the grippers are
opened (the levelling bar being for that purpose raised gradually by a
movement extending over the whole of the time set apart for the
weighing operation, so as to restrain and govern the vibration) whereas
it will be understood from what is stated above that in my improved
classifying machines I use the grippers finally to release the beam,
and leave it free to vibrate at once without hindrance from the levelling
arrangement of my Invention suited to the weighing and classifying
of coins and coin blanks into two denominations, light and heavy.
The weighing beam a is supported at its centre in the knife rest b,
which spans the long opening 'made for the reception of the beam in
the top plate A, and is fastened to the under side of the plate A.
Pendants a¹, a², have heads formed with suitable bearings for resting
on the knife edges at the ends of the beam. A weighing plate a³ is
provided for the coin or coin blank at the top of pendant a', which may
be termed the load pendant, and at the top of pendant a² a plate is
provided for counterpoise a'. It will be observed that the beam is
forked at the ends so that the pendants can hang down in the centre of
the fork. a are steadying weights placed on the pendants. Figure 3
shows another view of the lower ends of the pendants indicating
opening a provided for the levelling bar c to pass into. Levelling bar c
is provided with a centre upright c' to which it is fixed.
This upright

page_text: works in guides at bottom and top in frame c³, which is fixed to base
plate A. Pins c³, c*, pass into holes in bar cat ends, and act also as
guides. Adjusting screw serves to regulate the fall of the bar c, the
lower end of upright c¹ when down coming against it as a stop, while it
rests also on the pendants a¹, a², at a². Lever works on a pin in
projecting arm of frame c². The lower end of this lever passes freely
into a slot opening in upright c', and operates against the pin c³ to raise
the levelling bar c by the force of the spring c³ fastened to frame c, the
spring acting through the lever c to raise bar c, when levelling bar
cam callows the roller at the upper end of the lever c to pass on to
its smaller diameter. The return action is caused by the cam c³ in its
revolution forcing back the lever c, which allows the levelling bar c to
descend into the position shewn in the Drawing, in which position the
weighing beam is levelled. The cam c is fixed on to the main spindle B
which is supported in bearing hangers B₁ fastened to the under side of
top plate A. The grippers & serve to hold the load pendant a near the
top under the weighing plate, and to release when the operation of
weighing is to take place; the grippers are attached to the bridge piece d'
which spans the opening in top plate A, and is fixed to its under side.
The cam actuates the grippers through lever d³, the upper end of
which passes into a slot hole in the slide piece d', to which the two
levers of the grippers are attached by connecting rods d³. Spring do
acts against a pin in slide d' to close the grippers when the position
of the cam 2 permits, as is the case in the Drawing, the opening
of the grippers being effected by the action of the cam d on the
roller at the end of the lever d³. The lever d³ works on a pin supported
in a forked arm depending from bridge piece d'. Cam is fixed to
main spindle B. e is the hopper or reservoir for the coins; e¹ are coins
placed in it. The feeding slide e² is actuated by the cam grooved
cylinder through lever e and connecting link e*.
The covering
plate e serves to guide the feeding slide and to support the lower end of
the hopper e. Plate e is recessed on its under side to fit the slide e*.
In the Drawing the slide is shewn in its extreme outward position,
having just placed the coin e fairly upon the weighing plate a.
Levere has a roller at the end towards cam cylinder e³, which roller
fits and works in the cam groove formed on the cylinder; thus the lever
is caused to vibrate as the cam cylinder revolves, and give the necessary
and come motion to the feeding slide, which takes one coin at a time
in succession in the usual way, and places it upon the weighing plate
go

page_text: As the one coin is placed upon the weighing plate by the feeding slide
the coin next before placed thereon, and which has by this time been
weighed is pushed off the weighing plate by the on-coming coin between
the guide plates e³ (which keep it from diverging to the one side or the
other) and on to the directing edge ƒ (which in a manner to be herein-
after explained is caused, to occupy a position to the right or left of the
centre of the line of travel of the coin as it passes off the weighing plate
according as the coin may have been found light or heavy) so that the
coin is caused to topple over to the one side or to the other and fall into
one of the two tube channels e, e¹, and so be conducted into convenient
receptacles for the two denominations of coins or coin blanks. 'The
directing edge fis attached to a lever f¹ which vibrates on centre ƒ³,
being fixed to a centre pin which passes througli plates f³, ƒ*, and
works in them. Lever f³ is fixed to end of centre pin which projects
beyond front plate f³, and at its lower end is formed to catch against a
stop on the armature lever f". Armature lever f" is actuated by the
electro-magnet g (which is of the usual construction) when the coin
weighed is light, in which case the lever f' is attracted towards the
magnet, and lever f³ is disengaged so that spring f is permitted to
reverse the position of the directing edge, and so place it towards the left
hand, thus causing the off-coming coin to pass to the right and down
channel e into the receptacle for light coins. Lever f" has a spring
end which is fastened to support f' and tends upwards so that when the
magnet ceases to operate the other end of lever f' rises against the
adjusting screw f". Screw f" regulates the fall of the lever ƒ7. When
the lever f7 has been acted upon by the magnet and the lever f³ thereby
disengaged, it becomes necessary (before the next operation of weighing
is completed) to return the lever f³ and the directing edge to their
first position, or that in which they are shewn in the Drawing, this is
effected by cam f" on spindle B which acts through lever" (working
on pin at in pendant bracket ƒ³) against a pin ƒ" in lever ƒ³, so
as to force back lever until it passes the stop fª on lever f', and is
prevented from returning by the rising of the lever f, the end of
lever being thus caught against the stop fe on lever f'.
position has been attained the acting end of lever f¹³ falls
ponderating weight, the roller at the other end following the form of
the cam f, to cause the electro-magnet g to act upon the armature
lever f. When the coin is light weight the conducting wire g¹ is
placed under the weighing beam at the counterpoise end, and is
After this
by its pre-

page_text: arranged and held in a metal block g, which forms part of plate g³ and
can be adjusted to height by regulating screw * in plate g³. Plate g³ is
fixed to a non-conductor g³ which is screwed to the top plate A. The
conducting wire g¹ is connected electrically (the binding screw in
block serving) with the binding screw 91, which is connected with
the coil passing round the magnet g and with binding screw go from
which conducting wire g7 passes to the battery. Binding screw g³
connects wire go from the battery with the metal base of the machine
so that as the weighing beam rests with its centre knife edge on steel
bearings a complete circuit is formed, when the counterpoise end of the
beam is caused to descend by a light coin being placed on the weighing
plate at the other end, and is brought into contact with the conducting
wire g. When this circuit is completed the electro-magnet becomes
charged and lever fis attracted and lever fs disengaged, so as to place
the directing edge fin the proper position for directing the coin into the
channel e for light coins; the contact points of the beam and wire g¹
should be of platinum. The position in which the working parts of the
machine are shewn in the Drawing is that which immediately precedes the
raising of the levelling bar c, which (on reference to the arrow indicating
the direction in which the cams rotate, it will be seen) is about to take
place. The cam f¹² is also about to operate to reset the directing
edge f, which has not, however, in this instance been displaced; the
feeding slide is also just on the point of retiring by the action of cylinder
cam c³.
The grippers still hold the pendant a¹, but will open when the
rise d' on cam d² acts on the lever d³; the weighing then takes place,
and if the coin is light the directing edge is set through the medium
of the magnetic action; if, however, the coin is heavy the beam does
not make a contact, and the position of the directing edge is not
changed. The grippers remain open until the roller on lever d³ passes
on to the smaller diameter of the cam d, but before this takes place
the levelling bar is lowered by cam c³, acting on roller on end of lever c³.
By this time the cylinder cam e³ is causing the feeding slide to return
and put a fresh coin on to the weighing plate, displacing the last
weighed. It will be observed that from the form of cam f" the lever f¹³
must return immediately after it has been acted upon, the lever f³
is thus left free to be acted upon in case of the coin weighed proving
to be light. The times of the cams may be modified so as to give more
of the revolution for the weighing operation, and less for the placing
of the coin. For that purpose the form of the cam groove on the

page_text: cylinder may be varied so as to give a quicker action in the one
direction and a slower in the other, the other cams being varied in form
to accord with the cylinder cam e³. I prefer to make the end of the
conducting wire g¹ with which the beam comes into contact very slight,
so as to yield to the action of the beam to a small extent, and thus
maintain the contact longer than would be effected by a less elastic
contact; a guard may also be placed near the wire to protect it against
accident. It will be observed that the base and top plates of the
machine are bound together at the corners by four columns A³. In
cases when the centre knife edge of the beam is placed upon a gate
or other non-conducting rest, the clectrical circuit may be obtained
by the means indicated in Figures 4, 5, and 6, which are different views
of the same parts. a is a portion of a weighing beam; h, a short length
of wire loosely supported in V rest ⁄¹, which is attached to the under
side of the beam; ³, ³, are two conducting wires passing through a
non-conducting adjustable piece / and terminating in thin plates, the
upper edges of which are on the same level. These edges are adjusted
in height by the screws below, and the spiral spring shewn keeps the
piece steady so that the edges are near to the wire when the beam
is horizontal. When the beam ceases to be horizontal, owing to a
preponderating weight at the end where the wire is placed, the wire
comes into contact with the plates, and the electrical circuit is com-
pleted and the magnet charged. * represents a portion of a bridge
piece for carrying the piece ' with the conducting wires. Figures 7
and 8 show a similar arrangement, but the wire h in this case is carried
in a V-rest attached to the end of a weighing pendant a instead of to
the beam.
Figures 9 and 10 represent in elevation and plan respectively an
arrangement of my Invention for weighing and classifying coins and
coin blanks into three denominations or categories, the too light, the
too heavy, and the medium, or those pieces which are within certain
desired limits of weight towards the too heavy and towards the too
light, or in other words within a certain remedy or allowance on either
side of the standard weight. Many parts of this machine are similar
to those already described and referred to in Figures 1 and 2; such of
these parts as are shewn in Figures 9 and 10 are indicated generally
by similar letters and figures. In Figure 10 the covering plate e
to the feeding slide e² is removed. which shews the hole in the plate A

page_text: through which the attachment is made between lever e¹ and feeding
slide by link es. The differences between the machine already
described as for dividing the coins into two classes, and the machine
shewn in Figures 9 and 10 for dividing the coins into three classes, are
mainly confined to those parts which operate to cause the classification
of the coins into the three channel tubes 3, i, i³, instead of into the two
channel tubes e³, e¹º, of Figures 1 and 2.
Referring then to the machine illustrated in Figures 9 and 10, it
may be explained that the coins when displaced from the weighing
plate a³ fall down the inclined receiver i into the directing tube which
is attached by pins 2 to the receiver i. The directing tube is
arranged to vibrate upon the pins 2, so that its lower end can be placed
over either of the channel tubes ³, i, . These tubes conduct the coins
which pass into them into three separate receptacles, which may be
arranged in any convenient manner or position. The middle channel **
will lead the coins to the receptacle for coins of medium weight or
within the allowance arranged, and the channels and ³ may lead
respectively to the receptacles for the too light and the too heavy
coins.
It must be at once clear from what has been said that the classification
of the coins depends upon the position of the directing tube i¹. To
govern the position of this tube, so that the coins may after having been
weighed, be directed into the proper channels, two contact wires g', g',
are provided and placed one under each end of the beam, with means
of adjusting to height. When the operation of weighing takes place
the end of the weighing beam which is depressed by a preponderating
weight will come into contact with the conducting wire under it, and
so complete an electrical circuit, and, as the case may be, cause the
upper or lower magnet g to be charged and to attract the armature
lever j. This lever j vibrates on a pin j¹ in the support C, and is kept
in the middle position as shown in the Drawing by the retaining
levers, which are kept against lever j by the spiral spring j*,
while spring j³ acts against the depending end of lever j³ and forces it
against the stop screw jo, which is screwed into a projection upon the
support C¹; screw j thus becomes a stop by which the position of
lever j can be regulated, and so kept in a middle position between the
upper and lower magnets. Lever j in its vibrations actuates and places
the directing tube a, or when it is not acted upon by either of the

page_text: magnets it retains the tube
channel, the directing tube
by a pin fast in the projecting part of the tube and fitting in a slot in
the lever j. If the contact wire y¹ at the load end of the beam is con-
nected with the lower magnet g, the too heavy coins will cause the
lower magnet to be charged, and to act to draw down the lever j, and
so to place the lower end of the directing tube over the channel ³
which conducts to the receptacle for the too heavy coins. If the
counterpoise end of the beam is depressed by a too light coin being on
the weighing plate, the contact wire at that end will be touched by the
beam and a circuit established which will charge the upper magnet g,
and cause the reverse action in the lever j, bringing the directing tube
over the channel for the too light coins. Stop screws k, k, serve to
regulate the action of the lever j.
in its middle position over the middle
being connected to the end of lever j
The electrical connections are further indicated by dotted lines.
When the directing tube is acted upon so as to bring it over either
of the channels or the catch lever m rises by the force of the spiral
spring attached to it, and the small projection at its end catches against
the pin in the end of the directing tube and prevents it returning
until time has been given for the coin to pass down, when the cam m¹
acts on the roller at the other end of the lever and disengages the
directing tube ¹³, which returns to its middle position, as indicated in
the Drawing. Cam m³ therefore performs a nearly similar office to that
performed by cam f¹³ in Figures 1 and 2. Frames C and C¹ are
mounted on frame C. The ends of the weighing pendants a¹, a², are
provided with hooks for taking up remedy weights out of the V rests I, 1.
These weights represent the amount of allowance or remedy or the
excess of weight which must be raised at the one end or other of
the beam before the coin weighed is to be counted as too light or too
heavy.
Figure 11 shews another view of the end of pendants a¹, a³, as well as
of the remedy weight and V rest, with means for adjusting its height
so that the remedy weights just touch the hooks of the pendants when
the beam is horizontal. The stem of the V rest passes through a socket
piece fast to base plate A¹. Against a shoulder on the stem a spiral
spring acts to keep the rest up, while by the nut below its height can
be regulated:

page_text: Sometimes one remedy weight only is used equal to twice the remedy.
In that case it is applied to the counterpoise pendant, and the weight
of the counterpoise is reduced by the amount of weight represented by
one remedy, that is, by the quantity allowed plus or minus the standard
weight. In that case if the coin raises the counterpoise and along with
it the double remedy it is too heavy, but if the counterpoise alone raises
the coin the latter is too light.
My improved machines may be worked by hand by a descending
weight through regulated wheelwork, or by water, air, or other con-
venient power.
Having thus described the nature of my said Invention, and the
manner of performing the same, I would have it understood that I
claim the construction of weighing machines in such manner that the
turn of the beam by causing an electric contact controls a directing
instrument which determines the destination of the coin or article
weighed, substantially as described.
I also claim the directing edge f determining the destination of the
coin or article weighed, substantially as described.
I also claim the arrangement of the feeding slide moving in a
direction across the beam and actuated substantially as described.
I also claim the construction of weighing machines substantially as
described.
In witness whereof, I, the said James Murdoch Napier, have here-
unto set my hand and scal, this Thirtieth day of December, in the
year of our Lord One thousand eight hundred and seventy-one.
JAMES M. NAPIER. (L.S.)