Improvements in Portable Punching and Rivetting Machines.
Year: 1891

page_text: Date of Application, 28th Aug., 1891
Complete Specification Left, 3rd May, 1892-Accepted, 4th June, 1892
PROVISIONAL SPECIFICATION.
Improvements in Portable Punching and Rivetting Machines.
I, ALBERT CHARLES AUGUSTUS HOLZAPFEL, of 57 Fenchurch Street,, in the
City of London, Merchant, do hereby declare the nature of this invention to be as
follows:-
My invention relates to portable punching and rivetting machines worked by
hydraulic or other fluid pressure in which a punching or rivetting tool is moved by
the piston.so as to advance against and punch a plate or form the head of a rivet
held against it by an abutment on its other side.
The object of the present construction of apparatus is to render such machines
direct, acting and to make them more compact and applicable for working in small
and confined spaces.
For this purpose I construct the cylinder with an extended part or arm at the
end furthest from, the cylinder cover and at right, angles to the direction of move-
ment of the piston.
This extended part forms the abutment for containing the tool or die against
which the punch or, rivetting tool works. The piston is similarly, constructed with
a correspondingly extended part outside the cylinder cover at right angles to its
direction of movement and in this arm is fitted the punch. or rivetting tool in line
with and immediately opposite the abutment tool.
The cylinder, and piston are made of differential area at their two ends so that
when it is moved in the one direction doing work the fluid pressure acts on the
larger area and when it is moved in the reverse direction to release the punch or
tool from its work the fluid pressure acts on the smaller area.
The cylinder is also constructed with an abutment piece between the two pro-
jecting arms against which the plates bear when the punch is being withdrawn from
its work, thus preventing its backward movement with the punch beyond a certain
point and so facilitating the withdrawal of the latter.
According to a modified arrangement, instead of the moving arm being, made to
project from the piston rod outside the cylinder cover, it is made to project at right
angles, from the piston itself through a slot in the lower side, of the cylinder. In
this case the piston is made of greater length than its stroke and is provided with
paoking at its two ends to prevent leakage of the fluid pressure past. its working
Laces.
Dated this: 20th day of August. 1891.
ABEL & IMRAY,
Agents for the Applicant.
COMPLETE SPECIFICATION.
'Improvements in Portable Punching and Rivetting Machines.
I, ALBERT CHARLES AUGUSTUS HOLZAPFEL, of 57 Fenchurch Street, in the
City of London, Merchant, do hereby declare the nature of this invention, and in
what manner the game is to be performed, to be particularly described and ascertained
in and by the following statement:—
My invention relates to portable punching and rivetting machines worked by
hydraulic or other fluid pressure in which a punching or rivetting tool is moved by
the piston so as to advance against and punch a plate or form the head of a rivet
held against it by an abutment on its other side.
The object of the present construction of apparatus is to render such machines
31 ...מ

page_text: direct acting and to make them more compact and applicable for working in small
and confined spaces.
For this purpose I construct the cylinder with an extended part or arm at the
end furthest from the cylinder cover and at right angles to the direction of move-
ment of the piston.
This extended part forms the abutment for containing the tool or die against
which the punch or rivetting tool works. The piston is similarly, constructed with
a correspondingly. extended part outside the cylinder cover at right angles to its
direction of movement and in this arm is fitted the punch or rivetting tool in line
with and immediately opposite the abutment tool.
-
The cylinder and piston are made of differential area at their two ends so that
when the piston is moved in the one direction doing work, the fluid pressure acts on
the larger area and when it is moved in the reverse direction to release the punch
or tool from its work the fluid pressure acts on the smaller area.
The cylinder is also constructed with an abutment piece between the two pro-
jecting arms against which the plates bear when the punch is being withdrawn from
its work, thus preventing its backward movement with the punch beyond a certain
point and so facilitating the withdrawal of the latter.
According to a modified arrangement, instead of the moving arm being made to
project from the piston rod outside the cylinder cover it is made to project at right
angles from the piston itself through a slot in the lower side of the cylinder. In
this case the piston is made of greater length than its stroke and is provided with
packing at its two.ends to prevent leakage of the fluid pressure past its working
faces.
Fig. 1 of the accompanying drawing shews a longitudinal section of the first
before described arrangement of portable punching and rivetting machine constructed
according to my invention. A is a cylinder in which is a piston B having at one
end a small cylindrical extension B¹ fitting a cylindrical recess A³ at the end of the
cylinder A, and having also at the other end a cylindrical extension B working
through the cover C, outside which it is bent into elbow form and carries at its end
-a punching or rivetting die D. The cylinder A has a projecting arm A³ fitted with
an abutment piece E facing the punching or rivetting die D.
The cylinder communicates by a passage F at the front end and by a passage G
at the rear end with the fluid pressure supply which, for the punching or rivetting
action, operates on the annular front surface of the piston B, and for the return
movement, acts upon the small area of the extension B'.
It will be seen by the above description that power for the rivetting or punching
is transmitted directly from the piston B to the operating tool and that as the
cylinder is situated a certain distance above or below the arms carrying the die or
punch and abutinent, the punching or rivetting can be effected in confined spaces,
and in particular the punching and rivetting of the flanges of flanged plates near
the roots of the flanges and close up in the corners thereof can be readily effected
by the machine. Fig. 2 shews a longitudinal section of the second before described
arrangement of portable punching and rivetting machine, Fig. 3 shews a modifi-
cation thereof. In the arrangement shewn at Fig. 2 the cylinder A is formed with
8 slot A' and the piston B formed with a flat face B' opposite such slot to which
face is securely bolted an arm H projecting through the slot, and carrying at its
end the punching or rivetting die D situated opposite the abutment piece E carried
by the arm A of the cylinder A. 1 is a guard fixed to the cylinder when the
machine is used for punching, for facilitating the withdrawal of the punch from the
hole of the sheet metal operated on. A' is a cylindrical recess on the cylinder into
which fits a cylindrical extension B' on the piston so that by admitting fluid
pressure through the passage G, the piston and arm H are made to effect their
return motion, after having been forced forward by the fluid pressure admitted
through the passage F.
In the arrangement shewn at Fig. 3 the arm H is formed in one with the piston B,
instead of being fixed thereto, and in order to enable it to be introduced into the

page_text: slotted cylinder, this is formed in two separate parts as shewn, the front part A
being formed with the slot A' extending right to the rear end, so that the piston
can pass in through it, after which the rear part A', which constitutes the cylinder
proper, is bolted on to A by means of the flanges A*.
The other parts of the machine are precisely the same as previously described.
In either of the above arrangements, the length of the piston B can be varied in
proportion to the canting pressure exercised thereon due to the leverage of the
arm B or H, and when such canting pressure is considerable it may be relieved or
neutralised by providing another arın projecting from the opposite side of the piston
and sliding with its end against or upon a guide bar fixed to the cylinder frame, so
as to afford a support to such second arm at a leverage more or less the same as
that of the arm B' or H.
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. In a machine for punching and rivetting, the combination of a cylinder A having
a projecting arm A' carrying an abutment piece and a piston B subjected to fluid
pressure and having an elbow shaped extension B' extending laterally to the same
distance as the arm of the cylinder, and carrying the punching or rivetting tool,
substantially as described, with reference to Fig. 1 of the drawings.
2. In a machine for punching and rivetting, the combination of a cylinder A having
a projecting arm A carrying an abutment piece, and a longitudinal slot A³, and a
piston B-subjected to fluid pressure and having an arm H projecting laterally there-
from through the slot of the cylinder to the same distance as the arm of the cylinder
and carrying the punch or rivetting tool substantially as described with reference
to Figs. 2 and 3 of the drawings.
3. In punching and rivetting machines such as are referred to in the preceding
claims, providing the piston B with an extension of smaller diameter B' working in
a correspondingly smaller bore of the cylinder, so that for moving the piston back
after punching or rivetting, the fluid pressure is made to act upon the small area of
the part B¹, substantially as described.
9-11.
S M 1000
ABEL & IMRAY,
Agents for the Applicant.