Improvements in Hydraulic Forging Presses, and in Hydraulic Apparatus in connection therewith.
Year: 1896

page_text: Improvements in Hydraulic Forging Presses, and in Hydraulic
Apparatus in connection therewith.
I, CARL HUBER, of I Graben, No. 28, Vienna, Austria, Engineer, do hereby declare
the nature of this invention to be as follows:-
This invention relates to an improved construction of forging presses, the main
feature of which consists in the provision of two opposite horizontal hydraulic presses
which act simultaneously upon two opposite sides of the object to be forged, instead
of having only a single hydraulic press operating in combination with a stationary
abutment piece or anvil, as heretofor. By this arrangement the advantages are gained,
firstly that it is not necessary to turn over the object after each pressing, as the
compressing is effected perfectly uniformly on both sides; secondly the hammer
scale falls away at once from the vertical surfaces of the object after each pressing;
thirdly the manipulation of the auxiliary tools suspended from chains &c. such as
mandrels, chisels &c. is rendered very easy, fourthly, the compression is rendered
perfectly uniformn throughout the forging piece.
The forging press is for these purposes constructed as follows: Two hydraulic
cylinders arranged facing each other have at the front ends of their plungers cross
heads guided at top and bottom by horizontal guides on a strong bed frame rigidly
connecting the two cylinders. To the front faces of the plungers are attached
removeable heads that can be changed according to the nature of the forging to be
operated upon. The plungers have a central bore, that works over a central piston or
plunger fixed to the bottom of the hydraulic cylinder. The central fixed plunger has
a passage formed through it, which is connected by a pipe with a water pressure
distributing box from which a pipe also leads to the interior of the hydraulic cylinder
behind the main plunger. This plunger has its front part made of somewhat smaller
diameter than the inner end, so that while the latter fits the hydraulic cylinder an
annular space is formed between the front part and the cylinder, and this space can
also be put in communication with the water pressure distributing box.
The actuation and accurate control of the hydraulic plungers is effected by a
combined regulating and controlling slide valve apparatus so as to produce either the
simultaneous forward or the backward motion of both plungers, or the holding of the
one plunger stationary while the other is moved forward, the said apparatus being
also made to control the water pressure supply to each hydraulic cylinder so that the
plungers shall perform accurately the same advancing motion, and thus insure that
the forge piece shall always remain in the same central position.
Various constructions of regulating and controlling apparatus may be employed
for effecting these operations, but I prefer to employ the following arrangement. The
water pressure is first made to enter a chamber in which there is a double coned slide
governing two ports in such a manner that by moving the slide in one direction it
restricts the opening of the one part and increases that of the other. Each part

page_text: leads to a separate slide valve chamber one of which controls the supply and discharge
passages to and from the one hydraulic cylinder while the other controls those of the
other cylinder, both slides being moved simultaneously by one and the same hand.
lever. The said supply and discharge passages do not communicate directly with
their respective hydraulic cylinders but with the beforementioned water pressure
distributing box with which the passages from the hydraulic cylinder are connected
as follows.
The passage leading through the central fixed plunger communicates with a
compartment of the box connected directly to the fluid pressure supply from the
controlling valve chamber, while the passage leading from behind the main plunger
communicates with a second compartment, that is cut off from the first one by a valve
held closed by a strong spring.
The mode of operating is as follows. Assuming that the double coned regulating
valve is exactly in the middle position, then exactly the same volume of water under
pressure will enter each controlling valve chamber, so that if these valves are moved
so as to allow the water pressure to flow to the distributing boxes, it will at once pass
thence through the central passage of the fixed plunger of each hydmulie cylinder
into the hollow of the main plunger, so that hoth these will be advanced simultaneously
until they come in contact with the forge piece. During this time, the vacuum
formed behind the main plunger by its advance, causes water to be drawn from a
tank through a pipe communicating with the second compartment of the distributing
box and thence into the cylinder so as to fill the space behind the plunger with water
at atinospheric pressure. Owing to the resistance to the farther forward motion of
the plungers offered by the forging piece, the water pressure, in nccumulating in the
first compartment of the distributing chamber, will force open the spring valve of
the second ccmpartment, and the full water pressure will now pass both through the
ceutral passage and into the hydraulic cylinder behind the main plunger, thus
exercising the required forging pressure upon the forging piece. If during this
action it should be found that the one plunger, from any cause travels faster than
the other, the operator at once moves the double coned slide so as to restrict the
flow of water pressure to the former.
When the requisite forging action has been obtained, the operator reverses the
position of the controlling slides, whereby the beforementioned passages of the
hydraulic éylinders are put in communication with discharge ports, while on the other
haud a communication is established between a supply of moderate water pressure
and the beforementioned small annular space at the front part of the plungers, so that
by such water pressure the plungers are now made to perform their back stroke at the
same time forcing out the water behind them through the discharge ports.
If it be desired to only actuate the one press, the other being stationary, this is
simply effected by moving the double cone valve so that it cutirely closes the supply
port of that press which is to remain stationary.
The supply of water pressure may be produced by pumps in any known manner,
but I prefer to employ for this purpose the following arrangement of apparatus.
A vertical cylinder containing a heavily weighted plunger, similar to that of ordinary
hydraulic accumulators, has on the top of its framing a steam or other fluid pressure
cylinder of the same length as the accumulator cylinder, and whose piston is connected
by a rod to the crosshead of the accumulator plunger. The accumulator cylinder is
connected at botton either directly by a pipe to the chamber of the beforementioned
double coned regulating valve, or to a receiver which is connected with the latter.
When it is required to work the forging press, steam is admitted below the above-
mentioned piston, thereby raising the weighted plunger, and consequently drawing
in water into the accumulator cylinder from a suitable supply, so that on the discharge
of the steam from the upper cylinder the water is forced under the required pressure
from the accumulator to the double coned regulating valve of the press.
With the accumulator may be combined two small inverted cylinders in which
work plungers connected to the crosshead of the accumulator planger, so that on the
aising of the latter as described, water, previously drawn into the stall cylinders is forced

page_text: under corresponding moderate pressure either direct, into the annular spaces of the
hydraulic cylinders for effecting the backward motion, or into a receiver from which
it is supplied to the hydraulic cylinders when required for that purpose.
Dated this Nineteenth day of December 1896.
ABEL & IMRAY,
Agents for the Applicant.
Improvements in Hydraulic Forging Presses, and in Hydraulic
Apparatus in connection therewith.
I, CARL HUBER, of I Graben, No. 28, Vienna, Austria, Engineer, do hereby declare
the nature of this invention and in what manner the same is to be performed
be particularly described and ascertained in and by the following statement:-
This invention relates to an improved construction of forging presses, the main
feature of which consists in the provision of two opposite horizontal hydraulic presses
which act simultaneously upon two opposite sides of the object to be forged, instead of
having only a single hydraulic press operating in combination with a stationary abutment
piece or anvil, as heretofor. By this arrangement the advantages are gained, firstly,
that it is not necessary to turn over the object after each pressing, as the compressing
is effected perfectly uniformly on both sides; secondly, the hammer scale falls away
at once from the vertical surfaces of the object after each pressing; thirdly, the
manipulation of the auxiliary tools, suspended from chains &c. such as mandrels,
chisels &c. is rendered very easy.
The accompanying drawings shew a hydraulic forging press constructed according
to my said invention. Fig. 1 shews a side elevation partly in section, Fig. 2 a cross
section on line X X Fig. 1; Figs. 3, 4 and 5 shew respectively an enlarged vertical
section, side view, and end view of the controlling and regulating slide valve apparatus
and Fig. 6 a vertical section of the automatic lift valve apparatus.
A, A are two perfectly similar hydraulic cylinders, which are secured together by
means of four strong horizontal bars or columns B, and are fixed on a cast iron
base C. In each cylinder is a hydraulic piston-plunger D, the outer end of which bas
a cross-head E with four bearing blocks which slide on the bars B, and thus act as
very rigid guides for insuring the accurate rectilinear reciprocating motion of the
piston-plunger. The front face of the latter has a dovetail groove into which is fitted
the correspondingly dovetailed removeable forging head F. In the rear end of each
cylinder A is fixed a central auxiliary plunger G which fits a corresponding central
bore e of the plunger D.
The block of metal to be forged rests upon rollers on a table H, which is carried by
the plungers of two or more hydraulic cylinders J, so that by admitting or discharging
water pressure to and from these cylinders, the block can be raised or lowered to the
exact level desired relatively to the forging heads during the working thereof.
To the one cylinder A is fixed the casing of the regulating and controlling slide
valve apparatus K. This contains firstly a regulating slide M which is actuated by
means of an external hand wheel L Fig. 1 and is very sensitive, and secondly two
identical working slides 0 0 which are moved simultaneously by the hand lever N.
The chambers of the one side O are connected with the water spaces f and of the
one cylinder A by the pipes c and m and the chambers of the other slide are
connected with the same spaces of the other cylinder by means of the second set of
pipes c and m.
In each pipe c is included an automatic lift valve apparatus P, the arrangement
and object of which will be presently explained.

page_text: The pressure water delivered from a suitable pump enters the chamber I of
the regulating slide M through the pipe a, and is distributed by the slide M to
the two working slides 0 through the pipes b and b¹.
By the adjustment of the regulating slide M by means of the hand wheel L it is
rendered possible to so regulate the quantities of water supplied to the two
cylinders A A that, if these quantities are equal, the speed of advance of the two
plungers D is equal, while if the quantities supplied are unequal, the said speeds
are also unequal, and if the supply to the one cylinder be entirely cut off, its plunger
remains stationary, while the plunger of the other cylinder moves forward with a
speed which is double that of the plungers when both moving together.
As both cylinders must always work in a perfectly identical manner, with exception
of the said difference of speed, the following description of the action will be
confined to the working of one of the cylinders.
If the plungers D are to advance towards each other, the two working slides O are
so moved by means of the lever N, that the pressure water coming from the
regulating slide M, after passing through the chambers of the working slides, flows
through the pipes c into the valve apparatus P.
So long as the supply force pump only has to overcome the resistances of the
moving parts when working idle, it only works with a low pressure and the pressure
water which enters the valve apparatus P, flows, after passing through the same,
through pipe d and the central passage of the auxiliary plunger G, into the space e
of the working plunger D, where it effects the rapid forward movement thereof. The
vacuum thus produced in the space behind the plunger draws in filling water
through the pipe y and through the automatically acting check valve in the valve
apparatus P, such water being drawn in through pipe à from the reservoir i..
The valve V, which is loaded by a spring k prevents any passage of pressure
water into the space behind the working plunger, as the force of the spring & is
such as only to be overcome at a predetermined maximum pressure. This maximum
pressure will be exerted in the pipes c d at the moment when the forging head bears
against the object to be forged."
The valve V then opens, and pressure water passes also into the space behind the
plunger D, which will now operate with a correspondingly increased working pressure
on the object worked.
During the whole of the above described operation, the relative speeds of the two
plungers D can be regulated by a corresponding adjustment of the regulating
slide M.
The valve apparatus K consists of the slide valve casing in which are contained the
two perfectly identical working slides O, of which the upper one controls the
right hand cylinder, and the lower one the left hand cylinder, and the regulating
slide M, the slides O being moved longitudinally by the lever N and the slide M by
the hand-wheel I, as before stated.
The water from the supply force pump passes through the pipe a into the
chamber I of the regulating slide a whence it passes through the oppositely coned
openings XX into the chambers II and III. From chamber II it passes through
the pipe b into the chamber 1 of the upper working slide O, and froin chamber III
it passes through the pipe 6 into the chamber 2 of the lower slide O.
At the middle position of the slides shewn on the drawings, the water can flow
freely through the discharge pipes n back into the reservoirs. If the two slides O
be shifted to the left hand, for example, the pressure water contained in the
chambers and 2 will pass into the chambers 3 and 4, whence it is led through
the pipes c to the spaces behind the working plungers D.
l
The water forced out of the spaces by the forward movement of the plungers D
passes through the pipes m into the chambers 5 and 6 of the working slides O and
thence through the discharge pipes n into the reservoirs i, connected by the pipe o.
If now the working slides O be moved over to the right, the same action as that
described above takes place, the pressure water being conducted through the pipes m
to the annular spaces 2 in the front part of the cylinders, so as to force the piston

page_text: plungers D backward. The water forced out of the spaces e by the backward motion
of the piston plungers D, passes through the pipes d, valve apparatus P and pipes c
into the slide valve apparatus and thence through the pipes n into the reservoirs.
The water forced out of the spaces f by the same backward motion also passes the
same way, but, on entering the valve apparatus P through pipes g, it opens the
valve in order to enter the pipe c.
will
If the regulating slide is in its middle position, perfectly equal quantities of water
I pass to each hydraulic cylinder. If on the other hand it be moved from that
position it will be evident that owing to the coned form of the slide more water will
be made to flow to the one cylinder and less to the other one. The slide can be
shifted to such an extent that the communication with the one cylinder is entirely
closed, so that its plunger remains stationary, while the increased supply to the
other cylinder will cause its plunger to advance at double the speed.
Having now particularly described and ascertained the nature of this invention
and in what manner the same is to be performed I declare that what I
claim is :-
1. A hydraulic forging press consisting of two identical opposite horizontal
hydraulic cylinders A with vertical operating surfaces F carried by working pistons
or plungers that are made to act simultaneously on opposite sides of the object to be
forged, such plungers working with a central bore upon fixed auxiliary plungers G
and having their motion controlled by means of a valve apparatus K in such manner
that they can either be made to advance at the same speed or at different speeds,
the forward motion being effected by the admission of pressure water into the
spaces fand e, while the backward motion is effected by the admission of pressure
water into the front annular space substantially as described.
2. In a hydraulic forging press such as is referred to in the first claim, the
combination with the hydraulic cylinders A and moveable and fixed plungers D and G,
of pressure water distributing apparatus adapted to supply pressure water either to
the central bore e of the plungers D or to both this bore and the space f behind
such plungera, or to the annular space surrounding the front part of the plungers,
substantially as described.
し
3. In combination with the construction of forging press referred to in the first
claim, a controlling and regulating valve apparatus K consisting of a regulating
slide valve M actuated by a hand-wheel L and two working slide valves 0 Ŏ
simultaneously operated by a lever N, by means of which the pressure water can
be distributed in any desired manner to the two cylinders so as to effect either the
equal or unequal motion thereof, or to stop the motion of the one or the other at
any desired point, substantially as described.
4. In a forging press of the kind referred to in the first clain, the combination
with a fixed auxiliary plunger G working in a central bore of the plunger D, of a
valve apparatus P with valves V vso arranged, that for bringing the plunger G
up against the work, the pressure water is only admitted to the bore of the plunger
while at the same time water is drawn in behind the plunger through the check
valve v, the valve V being only forced open for the admission of pressure water
from the controlling valve apparatus K to behind the plunger through pipes c
and g after the plunger has been brought up against its work, substantially as
described.
5. A hydraulic forging press combined and operating as herein described with
reference to the accompanying drawings.
Dated this 20th day of September 1897.