Improvements in the Manufacture of Hollow Punches.
Year: 1890

page_text: Date of Application, 9th Dec., 1890
Complete Specification L-ft. 1st Aug.. 1891-Accepted, 19th Sept., 1891
PROVISIONAL SPECIFICATION.
Improvements in the Manufacture of Hollow Punches.
I, GEORGE SRAWLEY, of 298 Summer Lane Birmingham in the County of
Warwick Tool Manufacturer do hereby declare the nature of my said invention to
be as follows:-
My invention has for its object: improvements in the manufacture of hollow
punches for punching holes in leather, cloth, paper, and other material by which I
avoid the great tendency for the punch to split up the weld and the punch is
stronger and cheaper than in the case of forged and turned ones.
First: we take a bar of steel either square round or other section and either
stamp or press, by means of dies, the punch to the required external shape or con-
figuration. The piece of steel is then bent or cranked so as to enter a suitable
machine, where it is held firmly while two drills are brought to bear upon it, one a
large one for the back end and the other smaller for the front end-These two holes
are drilled simultaneously, one drill by preference, the little one is stopped before
the two meet and the larger one by preference completes the hole.
The gate is removed and the external part of the punch is now reset to shape by
a small mandril or drift put in the punch and the punch in dies and so pressed or
stamped into a true shape. I then apply emery wheels externally to finish the
outside and to sharpen the punch. The punch is then tempered hardened and
polished.
The machine is fitted with blocks to hold the metal after stamping while being
drilled and otherwise operated.
Dated the 0th day of Danamba 1900
GEORGE BARKER,
77, Colmore Row, Birmingham, Agent for Applicant.
COMPLETE SPECIFICATION.
Improvements in the Manufacture of Hollow Punches.
I GEORGE SRAWLEY of 298 Summer Lane Birmingham, in the County of
Warwick, Tool Manufacturer do hereby declare the nature of my said 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 improvements in the manufacture of hollow
punches, for punching holes in leather, cloth, paper, and other material by which I
avoid the great tendency for the punch to split up the weld and the punch is
stronger and cheaper than in the case of forged and turned ones.
First we take a bar of steel either square round or other section and either stamp
or press, by means of dies, the punch to the required external shape or configuration.
The piece of steel is then bent or cranked so as to enter a suitable machine where
it is held firmly while two drills are brought to bear upon it one a large one from
the back end and the other smaller for the front end-These two holes are drilled
simultaneously one drill by preference the little one stopped before, and the larger
one by preference completes the hole.
The gate is removed and the external part of the punch is now next to shape by
a small mandril or drift put in the punch and the punch in dies and so pressed or
stamped into a true shape. I then apply emery wheels externally to finish the
outside and to sharpen the punch. The punch is then tempered, hardened, and
polished.

page_text: The machine is fitted with blocks to hold the metal after stamping while being
drilled and otherwise operated.
In order that my invention may be clearly understood and more easily carried
into practice I have appended hereunto a double sized sheet of drawings upon
which I have fully illustrated the nature of my said improvements.
Figure 1, is a plan of part of a drilling machine showing my mode of drilling the
punches.
Figure 2, is a side elevation of the steel piece as stamped or pressed into shape
prior to drilling.
Figure 3, is a front elevation of the steel piece as stamped or pressed into shape
previously to drilling.
Figure 4, is a longitudinal section through the punch when complete.
In carrying my invention into effect I first take a bar of steel either square,
round, or other convenient section and stamp or press it by means of dies whilst hot
into the required external shape or configuration such as shewn by Figures 2 & 3.
The end a of the piece of steel is then cranked or bent into the form shewn in
Figure 1 to allow of it being placed in a suitable block D' in the drilling machine
which is made to receive it and where it is held firmly in any suitable manner
while the two, drills B and B are brought to bear upon it, the drill B' at the
back end a being larger than the one entering at the front end a². The two
holes and a are simultaneously drilled one of the drills, by preference the
smaller one, B2 being stopped before the two meet, and the larger one B¹ by
preference completes the hole. The punch is then removed from the machine and
a small mandril inserted in the drilled hole while the punch is placed in dies and
pressed or stamped into its true shape again as shewn by Figure 4. The outside is
then finished by the application of emery wheels to finish the outside and sharpen
the punch. The punch is then tempered hardened and polished.
Having now particularly described and ascertained the nature of my said invent
tion and in what manner the same is to be performed I declare that what I
claim is :-
The improvements, in the manufacture, of hollow punches substantially as and
for the purpose herein set forth and shewn upon the accompanying drawing.
Dated this 31st day of July 1891.
GEORGE BARKER,
77, Colmore Row, Birmingham, Agent for- Applicant.
GEORGE BARKER,
77, Colmore Row, Birmingham, Agent for. Applicant.