Shearing, Punching, Flanging or Analogous Operations.
Year: 1887

page_text: Shearing, Punching, Flanging, or Analogous Operations.
'
I, JAMES ARMER of 13 Clifton Road Brockley in the County of Kent 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:-
My Invention has for its object to provide hydraulic machines for pressing rivetting
shearing punching flanging or analogous operations which machines are very
economical in working.
According to my Invention I operate the ram of the press or operating part of the
machine during the portions of its strokes which are consequent upon the necessity
for giving headway or working space between the bed of the press or machine and
the ram or operating part for manipulating the material operated upon as distinguished
from the small extent of movement necessary to give the actual pressure or perform
the actual work of the machine. I provide in communication with the cylinder of the
press or machine a reservoir of liquid at a much lower pressure than that used for
the actual pressing, which flows freely to and from the said Cylinder whilst the ram
is moving through the larger portion of its stroke before it commences to exert the
full working pressure upon the materials; and during the corresponding return
stroke. I will call the said large portion of the forward strokes "the idle travel" of
the ram and the remaining portion of the stroke "the effective travel" and I will
call the travel in the reverse direction "the return travel." I arrange a valve in
connection with the ram of the press or machine so that as soon as the ram has com-
pleted its forward idle travel the said valve closes the communication between the

page_text: reservoir or low pressure liquid and the ram cylinder and at the commencement of
the return travel the said valve is again opened to re-establish the said communica-
tion. In connection with this valve is a cylinder and piston affording the means of
raising the valve and ram by pressure below the piston and of moving the ram through
the forward idle travel by pressure above the piston the actual pressure of the forward 5
effective travel being exerted upon the ram by admitting liquid under pressure at the
proper moment into the ram cylinder which may be effected in the usual way.
will more particularly describe my Invention with reference to a press constructed
according to my Invention for pressing Gunpowder from which its general application
will be understood. The accompanying Drawing is a vertical section of such a press.
The bed of the press is provided with recesses a for the reception of the Gunpowder
and provided with moveable bottoms constituted by plungers & operated by the ram C,
to the cylinder D of which liquid under high pressure is admitted after the main
ram E of the press has descended so that the plungers and ram E act to press the
contents of the recesses a and thereafter after the ram E is raised the said plungers 6 1
are moved further upwards to eject the moulded pieces from the recesses a. The
ram E works in the hydraulic cylinder G to which liquid under high pressure is
admitted by the inlet g from any suitable source of hydraulic power. Above the
cylinder G is situated a reservoir H containing liquid and having a communicating
passage g2 leading from the said reservoir to the said Cylinder. To the top of the
ram E a spindle I is attached loosely so as to have a small vertical "
play" The
said spindle is provided with a valve and a piston. The steni part works in a
cylinder J to which liquid which may be under constant pressure is admitted by the
inlet j. The piston divides the cylinder J from a small chamber K to which liquid
under pressure is admitted by the pipe k. The space between the stem part 3 and
the cylinder J presents an area at the underside of the piston sufficient to enable
the pressure admitted by the pipe to raise the ram E of the press when the pressure
is relieved from the top of the piston which presents an area sufficient to enable the
pressure admitted by the pipe k to overcome the combined pressure on the underside
of the valve j and on the underside of the piston . Since in this case a constant
pressure is used, it follows that the diameter of a must exceed in cross-sectional area
the area of the valve i presented to the pressure in the cylinder G presuming the
pressures admitted by the pipes gj k to be equal to each other.
The operation of the press is as follows.-
The material to be pressed having been placed in the recesses a in the bed the valve
on the pipe g being closed the valve on the pipe k is opened and the pressure exerted
upon the top of the piston causes the ram E to descend through the forward idle travel
the liquid flowing from the reservoir H through the passage g³ into the cylinder G
until the valve closes the said passage g². Pressure is then admitted by the pipe g
to give the forward effective travel to the ram E the connection of the spindle I with
the ram having as aforesaid sufficient play to allow of the necessary slight movement
of the ram E. In the press described the effective travel is very small and the
economy of hydraulic power in the complete working of the press correspondingly
great. The plungers bare at the same time raised by admitting pressure by the inlet d
so that the material in the spaces a is pressed between the tops of the plungers and
the underside of the ram E. The valve on the inlet g is then closed and pressure is
relieved from the chamber K a free outlet being established which may be effected in
any convenient way for example by making the valve on the pipe k a three-way valve
opening alternately to the source of pressure and the atmosphere. The constant
pressure on the underside of the piston then raises the valve i and the rain E imme-
diately follows through the return travel the liquid flowing from the cylinder G back
into the reservoir H through the passage g². The plungers b are then fully raised to
eject the pressed material.
It will be understood that the lower bed of the press may be of any suitable
construction as may be best suited to the purpose which the press is to serve.
I do not limit myself to the precise details illustrated as they may be varied
without departing from the nature of my Invention.

page_text: Having now particularly described and ascertained the nature of my Invention and
the manner in which the same may be performed I declare that what I claim is :-
First The arrangement and combination of parts constituting the machine for
pressing rivetting shearing punching flanging or analogous operations substantially
as herein before described and illustrated in the accompanying drawing.
Second In machines for pressing, rivetting, shearing, punching, flanging or
analogous operations the combination of the chambers or cylinders G J K and
means for admitting liquid under pressure thereinto the valve stem and piston
having the areas substantially as and operating for the purposes, herein before explained
with reference to the accompanying Drawing.
Third The combination with the subject matter of the last preceding claiming
clause of the reservoir H communicating by the passage with the cylinder G
substantially as and for the purposes hereinbefore described with reference to the
accompanying Drawing.