IMPROVEMENTS IN COINING PRESSES
Year: 1867

page_text: LETTERS PATENT to James Murdoch Napier, of York Road, Lambeth,
in the County of Surrey, for the Invention of " IMPROVEMENTS IN COINING
PRESSES."
Sealed the 18th February 1868, and dated the 21st August 1867.
PROVISIONAL SPECIFICATION left by the said James Murdoch Napier.
at the Office of the Commissioners of Patents, with his Petition, on the
21st August 1867.
I, JAMES MURDOCH NAPIER,, of York Road, Lambeth, in the County, of
Surrey, do hereby declare the nature of the said Invention for "IMPROVEMENTS,
IN COINING PRESSES," to be as follows:-
This Invention has for its object improvements in coining presses, and
consist in the application of hydraulic pressure exerted through a force pump,
or other means upon a ram or piston, and so employed as to bring the coining
dies forcibly to act upon and impress blanks supplied in succession to them.
To separate the dies and allow the piece last under pressure to be displaced
and a fresh blank introduced I provide valves, by actuating which the flow of
the water may be reversed and caused to act upon the opposite side of the
piston where the area is less, and so withdraw it, while the water on the other
side of the piston is at the same time forced out of the cylinder through
valve which is opened to admit of its egress. But instead of forming the ram
with a piston bead and allowing the pressure of the water to act alternately
on the one side and on the other of the piston, I prefer to make the ram

page_text: plain and without a piston head, and to employ atmospheric pressure to return
it into its cylinder and separate the dies, and for that purpose I provide a
suction pump in connection with a vacuum chamber, which is kept exhausted
by it, so that upon the closing of the valve which admits the water under
pressure into the ram cylinder, a valve which I provide for opening and
closing the communication between the ram cylinder and the vacuum chamber
may be opened. When this takes place, the water which has forced the ram
outwards is drawn out of the ram cylinder and the ram is withdrawn into the
cylinder by the pressure of the atmosphere, and takes the place which the
water occupied. I prefer to place the force pump or pumps separate from
the coining press, and to employ them to force the water into an accumulator
or cylinder, having a loaded ram or plunger, so that as the pressure is wanted
I can obtain it by actuating a valve suitably arranged to open a communication
between the accumulator and the ram cylinder of the coining press; this valve
I cause to be closed as soon as time sufficient has been allowed for, the blank to
be impressed, after which the valve communicating with the vacuum chamber
is in its turn opened; these valves are opened and closed mechanically at
suitable times. I also provide mechanism to act in concert with the
mechanism for working the valves for the purpose of feeding the blanks to the
coining press from a suitable hopper or reservoir and for displacing the pieces
after they are impressed, or coined...
:
In cases where there are several coining presses, placed sufficiently near
together, I prefer to make one force pump apparatus and one accumulator
serve for the whole, and also one suction pump apparatus and one vacuum
chamber. When desired I employ water at a comparatively low pressure to
act upon the ram; so as to bring the dies into contact with the blank under
treatment, and immediately upon that being accomplished I cause the valve
connecting the r.m cylinder with the low pressure to close, and the valve
connecting the rain cylinder with the high pressure, to open. By this means
less high pressure, water will be used. The valves of the' high and low
pressure service will act in concert with the valve connecting the ram
cylinder and the vacuum chamber: For the low pressure water service a
separate force pump apparatus and accumulator is provided.
.
I employ suitable mechanism for actuating the collar which supports the
edge or circumference of the blank when the pressure is applied, and which
collar is sometimes complete, as when the edge of the piece is to be milled or
plain, and sometimes "broken" or formed in pieces, as in the case where the
edge of the piece is to be lettered. This mechanism acts in concert with the
mechanisms already referred to for opening and closing the valves and

page_text: actuating the feeding and displacing apparatus. In order to the free ingress
and egress of the water to and from the ram cylinder, and to avoid pipes and
valves inconveniently large several sets of connections and valves may be
used. I prefer to actuate the valves of my improved coining press by cams
placed on a rotating shaft or shafts, and acting upon the valves by means
of levers.
The other mechanisms to which I have referred are also worked from a
rotating shaft or shafts, any convenient power may be employed for driving
the parts of the coining press and the pumps used in the working of the press.
I
My improvements refer also to lever coining presses, in which presses
place the lever (through which the pressure for impressing the coin is given).
in a position below the coining dies, and I actuate the lower die and raise it
towards the upper die to give the pressure by means of the lever which is
beneath it, instead of placing the lever (as is usual in such coining presses)
above the dies to actuate the upper die, and give the pressure by bringing it
down towards the lower die. This mode of action enables me to effect a
better and more convenient arrangement of the parts of the lever coining
press.
I also employ carrying bands for removing the coined pieces from coining
presses to convenient receptacles or places. I make the frame heads of lever
coining presses and of my improved bydraulic coining press of cast steel, by
which I obtain great strength and lightness.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said James Murdoch Napier in the Great Seal Patent Office,
on the 21st February 1868.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JAMES
MURDOCH NAPIER, of York Road, Lambeth, in the County of Surrey, send
greeting.
of
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-first day of August, in the year of our
Lord One thousand eight hundred and sixty-seven, in the thirty-first year
Her reign, did, for Herself, Her heirs and successors, give aud grant unto
me,.
, the said James. Murdoch Napier, Her special licence that 1, 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

page_text: and at all times thereafter during the term therein expressed, should. and
lawfully might make, use, exercise, and. vend, within the United Kingdoni of
Great Britain and Ireland, the Channel Islands, and Isle of Man, an Inven
tion for "IMPROVEMENTS IN COINING PRESSES," upon the condition (amongst
others) that I, the said James Murdoch. Napier, my executors or adminis
trators, 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 coining presses,.and
consists in the application of hydraulic pressure exerted through
a force pump
or other means upon a ram or piston, and so employed as to bring the coining
dies forcibly. to act upon and impress blanks supplied in succession to them;
To separate the dies and allow. the piece. last under pressure to be displaced
and a fresh blank introduced, I provide valves, by actuating which the flow of
the water may be reversed and caused to act upon the opposite side of the
piston where the area is less, and so withdraw it while the water, on the other
side of the piston is at,
the same time forced out of the cylinder through a
valve which is opened to admit of its egress. But instead of forming the ram
with a piston head, and allowing the pressure of the water to act alternately
on the one side and on the other of the piston, I prefer to make the ram
plain and without a piston head, and to employ atmospheric pressure to
return it into its cylinder and separate the dies; and for that purpose I
provide a suction. pump in connection with a vacuum chamber, which, is kept
exhausted by it, so that upon the closing of the valve which admits the water
under pressure into the ram cylinder, a valve which I provide for opening and
closing the communication between the ram. cylinder and the vacuum
chamber may be opened. When this takes place the water which has forced
the ram outwards is. drawn out of the ram cylinder, and the ram is withdrawn
into the cylinder.. by the pressure of the atmosphere, and takes the place
which the water occupied. I prefer to.. place the forcé pump. or. pumps
separate, from the. coining press, and to employ them to force the water into
an accumulator, or cylinder having. a loaded.ram or plunger, so, that as the
pressure is wanted I can obtain it by actuating a valve suitably arranged, to

page_text: open a communication between the accumulator and the ram cylinder of the
coining press. This valve I cause to be closed as soon as time sufficient bas
been allowed for the blank to be impressed, after which the valve com-
municating with the vacuum chamber is in its turn opened. These valves
I also provide
are opened and closed mechanically at suitable times.
mechanism to act in concert with the mechanism for working the valves for
the purpose of feeding the blanks to the coining press from a suitable
hopper or. reservoir, and for displacing the pieces after they are impressed. or
coined.
In cases where there are several coining presses placed sufficiently near
together I prefer to make one force pump apparatus and one accumulator
serve for the whole, and also one suction pump apparatus and one vacuum
chamber. When desired I employ water at a comparatively low pressure to
act upon the ram, so as to bring the dies into contact with the blank under.
treatment, and immediately upon that being accomplished I cause the valve
connecting the ram cylinder with the low pressure to close, and the valve
connecting the ram cylinder with the high pressure to open. By this means
less high pressure water will be used. The valves of the high and low
pressure service will act in concert with the valve connecting the ram cylinder
and the vacuum chamber. For the low pressure water service a separate
force pump apparatus and accumulator is provided.
I employ suitable mechanism for actuating the collar which supports the
edge or circumference of the blank when the pressure is applied, and which
collar is sometimes complete as when the edge of the piece is to be milled
or plain, and sometimes "broken" or formed in pieces, as in the case where
the edge of the piece is to be lettered. This mechanism acts in concert with
the mechanisms already referred to for opening and closing the valves; and
actuating the feeding and displacing apparatus. In order to the free ingress
and egress of the water to and from the ram cylinder, and to avoid pipes
and valves inconveniently large, several sets of connections and valves may
be used; I prefer to actuate the valves of my improved coining press by
cams placed on a rotating shaft or shafts and acting upon the valves by means
of levers.
The other mechanisms to which I have referred are also worked from a
rotating shaft or shafts. Any convenient power may be employed for driving
the parts of the coining press and the pumps used in the working of the
press.
:
My improvements refer also to lever coining presses, in which presses I
place the lever (through which the pressure for impressing the coin is given)

page_text: Figures 1, 2, and 3, Drawing No. 1, represent my improved bydraulic
coining press, in which I have shown the hydraulic cylinder and ram placed
in the upper part of the frame of the press and above the dies, and the several
Figures comprised in Drawing No. 2 illustrate another form of my improved
hydraulic coining press, in which the cylinder and ram are arranged in the
lower part of the frame head and below the dies.
I will in the first place describe that form of my coining press shown in
'Figures 1, 2, and 3, Drawing No. 1, in which motion is given to the upper
die, as in the ordinary lever coining press, but instead of being cominunicated
to the die by means of a lever and toggle joints, or other usual means, the die
is actuated through its connection with the hydraulic ram in concert with
which it moves. The upper die being in this instance the moving one the
usual arrangements of the split or broken collar may be employed for
impressing the edge of the piece when desired, which arrangements I have
not therefore thought it necessary to shew in the Drawing.
In order also to simplify the Drawing I have shown only one valve which
acts to allow of the ingress and egress at suitable intervals of the water which
exerts the pressure upon the end of the ram or piston; and I have supposed
the pressure of the water on the other side of the piston or reduced side of the
ram to be constant for the return of the ram to its raised position. A valve
or valves may however be used, as it will be clearly seen to regulate the
ingress and egress at suitable times of the water which exerts the necessary
pressure upon the piston to return it.to its raised position.

page_text: 1 is the frame head of the press, which may be made of cast iron, as usual,
but in cases where lightness with strength are required I make it of cast
steel. 2 is the ram cylinder. 3, the ram which is reduced in diameter at 4, so
as to form a piston end. The pressure for bringing down the die forcibly
upon the blank is given on the end of the piston at 5, and the return pressure
for raising the ram is exerted upon the .comparatively limited surface of the
piston head at 6. The pipe 7 is connected with any suitably arranged
accumulator from which. the supply of water under pressure for working the
ram is obtained. Pipe 8 is a branch of pipe 7, and supplies a constant
pressure of water to the under side of the piston at 6; this pressure is
overcome by the downward pressure when it is exerted upon the greater area
at 5, but when that pressure ceases the upward pressure at 6 is sufficient in
its turn to raise the piston. 9 is the discharge pipe through which the water
escapes after having done its work. 10 is a piston balanced valve which
works in the cylinder 11; this valve is connected by rod 12 to lever 13,
which is actuated at its lower end by cam 14 upon the shaft 15 which revolves
in the direction of the arrow, the spring 16 serving to keep the roller at the
end of lever 13 against the cam as it rotates, and so perform the return action
of the valve 10.
In Figure 1 valve 10 is shown in that position in which it closes the
communication between the supply pipe 7 and the opening 17 into the
cylinder 2, while it leaves open the communication between the upper end of
the cylinder and the discharge or exhaust pipe 9. In Figure 3 the position
of the valve 10 is changed, and the pressure supply pipe 7 is in communication
with the end of the cylinder 2, so that the water under pressure may flow into
it through the opening 17 and apply the necessary force upon the ram or
piston 3 for impressing the blank under treatment; the connection with the
discharge pipe 9 is at the same time closed. Thus by the working of the
valve 10 the water under pressure is allowed to act upon the ram or piston 3
at suitable intervals so as to force it down against the constant pressure
exerted by the water upon the comparatively limited area of the piston head
at 6, and with sufficient additional force so as to cause the die which is
connected with it to impress or coin the blank. 18 is the upper die which is
beld in the piece 19 and may be regulated to height by the wedge 20 which
applies against the block 21 in the rain 3. The lower die 22 is placed in
its holder 23 which rests upon the block 24 under which the wedge 25 is
placed; this wedge serves to adjust the height of the lower die. 26 is such
a collar as may be used to support and impress the edge of the piece when it
is to be either plain or milled and is what may be termed a whole or complete

page_text: collar, and not a broken or divided collar such as are commonly used when
the edge of the piece is to be lettered. 27 is a carrying plate for the
collar 26, this plate has guides at 28 and is caused to rise and fall along with
the collar at suitable times by the lever 29 and cam 30 which is placed upon
the shaft 15. The lever 29 acts upon the fixed centre at 31 and is formed
double so as to attach by slotted holes in the ends to two pins in the
carrying, plate 27 at 32 and 33 near the guide 28. The return action of the
lever 29 is assisted by the spiral spring 34; cam 35, lever 36, and connecting
rod 37 serve for actuating the feeding slide for supplying the blanks from a
hopper in the usual way to the dies 'and for displacing the finished piece.
The feeding slide may be such as are commonly used for such purpose. The
cam 35 is fixed to the shaft 15 and in its revolutions communicates the
required moveinents to the feeding slide, the spring 38 being employed to
Keep the roller 39 against the cam and to actuate the lever when placing the
new piece in position and displacing the previous piece. The hydraulic
cylinder is supported and firmly fixed in the frame head 1, and the strong
'abutment pieces forming part of the frame head at 40 and 41 serve to arrest
the descent of the ram and so to prevent the dies coming into contact in case
no blank is between them, and otherwise to prevent at any time excessive
pressure upon the blank..
"
In Figures 1 and 2 the ram with the upper die is shewn raised and the
blank is placed upon the lower die, the collar and plate are about to rise and
the valve 10 is about to open the communication and allow the water under
pressure to force down the ram 3. In Figure 3 the ram 3 is shown in its
lowest position and the piece is under pressure between the dies, the collar
being raised, and the valve 10 so placed that the pressure of the water nets
upon the ram to force it down.
Drawing No. 2 shows the other form of my hydraulic coining press to
which I have referred, in which the cylinder and ram are placed below the
dies, so that the lower die moves while the upper die remains fixed.
The description. which I have already given of the machine shewn in
Figures 1, 2, and 3, Drawing No. 1, will enable this arrangement of thy
Invention to be at once clearly understood, I may however observe that in
this case the ram 3 is plain and without piston head, and that the pipe 9 which
carries away the water from the cylinder is to be connected with a vacuum
chamber which is kept exhausted by a suitable pump. By this means the
pressure of the atmosphere is caused to act upon the ram to return it to its
lowest position. The Figures 1 and 2 shew the-dies separated, while Figure 3
shows the piece under pressure; 42 is the hopper for containing the blanks; 44

page_text: and 45 are rollers for guiding carrying, band 46 which receives the coins and
carries them to any convenient situation. I have placed similar indicating
Figures upon the parts shown in Drawing No. 2 as upon those: parts which
are of the same description and shewn in Drawing No.:1.
Figures 4, 5, 6, 7, 8, and 9, Drawing No. 2, are enlarged views showing
various positions of the acting parts of the machine, and will assist to make
still more clear, the description which I have given of the Figures 1, 2, and 3,
Drawing No. 1, to which description however I may add that the piece B is
intended to be firmly fixed to the head of the ram 3 so as to rise and fall with
it; in this piece the holder for the upper die is beld and supported by means
of the wedges a, a. Any suitable force pump and accumulator may be used
to give the necessary water pressure, and any other suitable valves may be
used for opening, and closing the communications if desired. The vacuum
chamber and air pump may also be arranged in any convenient manner.
These accessories I have not thought it. necessary to illustrate or describe as
they are already. well understood.
.L
Figures 4, 5, and 6, Drawing No. 1, illustrate my improvements in-the
lever coining press.in which the lever action usually arranged above, the dies
in the upper part of the frame bead is applied below the dies, and in such a
manner as to render the press more simple and compact as well as more
convenient than the ordinary lever press.
Any convenient arrangement of apparatus for feeding the blanks and for
actuating the collar may be employed, but I have in these Figures indicated
the same mode as already described in connection with my bydraulic coining
press.
In Figures 4 and 5 the dies are shown separated, and in Figure 6
they are shown closed upon the piece or blank- which is being coined, the
slide A which carries the lower die may be weighted if necessary so as to
descend with greater certainty, or springs may be used to draw it downwards
and keep the lever and toggle joints in secure contact. It will be observed
that the lower die is placed in a holder 6 which has guides c, c; this holder
is raised by the action of slide e when the pressure is to be given, as is the
case in Figure 6, and as the slide A retires after the pressure has been exerted
the holder 6 is forced down by the springs f, f, until it rests upon the abut-
ments at 9, 9, in contact with which it remains until again raised, when resting
upon the abutments the lower die should be at the proper level for the coming
on of the next piece.
It will be understood that the mechanical arrangements of my coining
presses may be varied from those which I have more particularly set forth
and described, but I would observe that an important feature of my Invention
°

page_text: is the arranging the mechanism in such manner that the valves are opened
and closed mechanically at suitable times and in concert with the mechanism
for feeding blanks to the coining dies, and for actuating the collar, the several
motions being obtained by cams or equivalent instruments placed on a rotating
shaft or shafts. The accumulator which I prefer to use is one of small
capacity and loaded to a considerable pressure such as, say, to one, two, or
three tons pressure upon the square inch, as by such means the cylinder of
the press may be kept of conveniently small dimensions and sufficient pressure
to coin the blanks obtained. The necessary pressure will of course depend
upon the size of the blank, and the kind of relief required, as well as upon
other circumstances, such as the quality or hardness of the metal. By the
'use of my hydraulic coining press the great friction and complicated mechanism
of the lever press, as well as the wear and tear, will be avoided.. The use of
the abutment pieces against which the ram head takes its bearing as already
described are important to regulate the pressure against the blank and
prevent the destruction of the dies when there is no piece or blank between
them.
In witness whereof, I, the said James Murdoch Napier, have hereunto
set my band and seal, this Twenty-first day of March, in the
our Lord One thousand eight hundred and sixty-eight.
year
of
JAMES M. NAPIER. (L.S.)