IMPROVEMENTS IN PORTABLE PUNCHING MACHINES
Year: 1876

page_text: LETTERS PATENT to John Fielding, Engineer, of the Atlas Iron Works,
Gloucester, in the County of Gloucester, for the Invention of "IMPROVEMENTS
IN PORTABLE PUNCHING MACHINES."
Sealed the 30th September 1876, and dated the 5th April 1870.
PROVISIONAL SPECIFICATION left by the said John Fielding at the Office
of the Commissioners of Patents on the 5th April 1876.
JOHN FIELDING, Engineer, of the Atlas Iron Works, Gloucester, in the County of
Gloucester. "IMPROVEMENTS IN PORTABLE PUNCHING MACHINES."
This Invention has for object improvements in portable hydraulic punching
machines, and consists chiefly in making the cylinder noveable with the main screw
for the purpose of bringing the preliminary pressure on to cylinders and for drawing
the punch out of the hole. One method of carrying my Invention into effect is as
follows: The body of the machine is formed either with two open jaws for the
insertion of the plate to be punched, or with a space closed at two sides with
sufficient room for the introduction of bars or rails which are to be punched.
For convenience of description it shall be supposed that the machine is formed
with open jaws. One of these jaws is arranged suitably for carrying the hollow
punching die. The other is bored and has a thread cut in it to receive a screw
which carries the punch. This I will call the main screw. To the outer end of
this main screw which is hollow throughout its length is attached a cylinder
(which I will call the main cylinder), within which works a piston packed with a
cupped leather or other suitable packing. In connection with this piston is a rod
or stem which extends down within the hollow main screw and abuts against the
end of the punch, which is held in the main screw in such a manner that whilst it
is free to move freely end ways it is prevented from coming entirely out.
At the outer extremity of the main cylinder is a smaller cylinder, (which may be
made in one piece with the main cylinder, or separate from it, and attached in any
suitable manner.
Within this smaller cylinder fits a piston packed by means of a cupped leather or
other suitable packing. This piston is free to move within the cylinder. A second
screw is provided at the outer end of the smaller cylinder, and work into a nut which
may be made in one piece with this cylinder. The inner end of the second screw
takes a bearing against the small piston, which in the operation of punching it forces
[Price Gd.1

page_text: towards the larger. piston. The space between the two pistons being open to both,
it follows that upon the space being filled with water, oil, or any liquid of a similar
nature, whatever motion is given to the small piston through the medium of the
second screw, this motion is directly transmitted to the larger piston in the main
cylinder in proportion to the areas of the respective pistons.
The main screw performs two functions, firstly, that of creating a certain pressure
within the cylinders by the act of forcing the punch against the plate (preparatory
to the final pressure required to punch the plate being given by forcing the small
piston towards the larger one by means of the second screw); this also fixes the
machine firmly on to the plate, which much facilitates the working of the second
screw.
Secondly. It withdraws the punch from the hole after the plate has been punched
by simply unscrewing it within the jaw.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said John Fielding in the Great Seal Patent Office on the 5th October
1876.
JOIN FIELDING, Engineer, of the Atlas Iron Works, Gloucester, in the County of
Gloucester. "IMPROVEMENTS IN PORTABLE PUNCHING MACHINES."
This Invention has for object improvements in portable hydraulic punching
machines or "bears" in which the body of the machine is formed with two open
jaws for the insertion of the plate to be punched, or with a space closed at two
sides with sufficient room for the introduction of bars or rails which have to be
punched.
The machine, shown in the accompanying Drawings, Figure 1 section, Figure 2
top view, and Figure 3 face view, has open jaws A, B, one A formed for taking
the hollow punching die C and the other B bored, and with a screw thread cut in
it for the reception of the main screw shaft D which carries the punch. E. This
main screw D is hollow from end to end, and is fitted with a piston rod F, the
lower end of which acts upon the punch E. The upper end of the main screw
carries a cylinder G in which works a piston H of the rod F, the piston being packed
in the usual manner.
Above the cylinder G is a smaller cylinder I (one leading into the other as
shown) for carrying a plug piston J, upon the head of which a threaded rod K can
act when it is screwed into and through the cap L to push the plug piston J down-
wards, supposing the machine to be used in a vertical position. The head of the
rod K is formed with a square or equivalent shaped head, as is also the head portion
M of the cylinders G, I, to enable them to be acted upon by a spanner, or as
convenient.
The punch or tool E is fitted to move within the screw D, but not to come
entirely out.
N is the plug hole by which the cylinder is charged with oil or water as
desired.
The mode of working the machine is as follows:-The cylinders G, I, being
charged with oil or other suitable liquid the small screw K is raised to its highest
position with a wrench, which is suitably formed to fit the small screw K, and the
suitably formed part M of the cap on the hydraulic cylinder G. The main
screw D is then turned to move downwards, till a slight pressure is brought upon
the liquid in the cylinder enough, say, to bring the punch fairly and closely to its
work. Then remove the wrench to the lead of the small screw K, and screw the
latter down until the plate is punched.
After running back the small screw K the punch may be withdrawn by un-
serewing the main screw D.

page_text: Having now described the nature of my said Invention, and in what manner the
same is to be performed, I declare that I claim the improvements in portable
hydraulic punching machines or " bears" comprising the two cylinders and pistons
which act in conjunction as described for the purpose set forth, and the construction
of the machine substantially as shown in the accompanying Drawings.
In witness whereof, I, the said John Fielding, have hereunto set my hand
and seal, this Twenty-sixth day of September, One thousand eight hundred
and seventy-six.
JOHN FIELDING. (L..S.)