AN IMPROVED CONSTRUCTION OF PUNCHING MACHINE
Year: 1868

page_text: PROVISIONAL SPECIFICATION left by Richard Hodson at the Office
of the Commissioners of Patents, with his Petition, on the 15th
September 1868.
I, RICHARD HODSON, of West Ham, in the County of Essex, Engineer,
do hereby declare the nature of the said Invention for "AN IMPROVED
CONSTRUCTION OF PUNCHING MACHINE," to be as follows:-
This Invention relates to the automatic punching, in iron plates: and
other articles, of holes at equal and irregular distances apart, the punches
used being capable of being thrown into or out of action at the pleasure
of the operator or attendant. The punching machine or press consists of
a fixed bed for carrying the counter dies made fast to strong end
standards which support the operating parts of the machine. Turning
in bearings in the upper end of the standards is a longitudinal driving
shaft, which receives motion from any prime mover. This shaft is
mounted excentrically, and it is embraced by saddles attached to the
upper face of a compound slide extending from end to end of the-
machine. The shaft is also surrounded by straps attached to the opposite.
ends of the slide; the rotation therefore of the excentric shaft will. raise.

page_text: and depress the slide. The slide is made of two parts, and they are
.connected together by screws passed through holes, those in the lower
part of the slide being elongated to allow of the upper part receiving at
times an independent up-and-down motion. In cross section the upper
part of the slide is T-shaped, and the lower part resembles a reversed
1. Pivotted to the outer vertical face of this lower part are cranked
levers, which serve to operate sliding blocks carried by the lower part
of the slide; these blocks, when the machine is required to act, are
thrust forward under the tail of the T-shaped slide and receive and
transmit the pressure therefrom to the lower part of the slide. Below
this slide the punches are situated, and from it they receive the pressure
which causes them to descend and pass through the plates or other
articles placed below them to be punched. The punches work through
adjustable guides fitted to a slotted horizontal sliding bar, which is
capable of receiving a traverse motion for the purpose of feeding the
plate forward after the operation of the punches. The plate to be
punched rests upon the counter dies carried by the fixed bed, and these
dies are fitted with loose collars (notched in the direction of the traverse
of the plate). to lift the plate from the counter dies and thus to prevent
the burr formed in the act of punching from interfering with the feed
traverse of the plate. These loose collars are lifted at the proper time by
arms keyed to a rock shaft, which is operated from a cam on the
excentric shaft before mentioned. In order to allow of a selection of
the punches being put into and thrown out of action at pleasure, on the
under face of the slide is formed a dovetailed groove, in which are fitted
sliding steel blocks; these blocks when in position will overlie the
heads of the selected punches, and the descent of the slide will cause
those punches to act, but when withdrawn the heads of those punches
will on the depression of the slide merely enter the dovetailed slot, and
no pressure will be imparted to them. The sliding blocks are worked
by being connected by rods 'to bell-crank or rock levors, which may be
set in action by a hand lever, or automatically by means of a crank pin
'fitted to a short shaft carrying a chain wheel. The rotation of this shaft
serves also to give the feed motion to the sliding punch bar. At the
back of the machine is a longitudinal shaft, to the ends of which (outside
the standards) are keyed crank arms; fitted to these are connecting
rods, the other ends of which hang on rods carried by brackets affixed to
the front of the punch bar. This longitudinal. shaft has a pinion in gear

page_text: with a wheel on the chain wheel shaft. The chain wheel is loose on its
shaft, and it carries a pawl which enters the teeth of a ratchet wheel
keyed to the chain wheel shaft. The chain of this wheel carries a
weight at one end, and at the other is secured to a finger carried by
a vertical sliding rod, which is also weighted; this rod is also fitted
with a tappet upon which a sliding tooth carried by a second vertical
sliding rod acts to lift the weighted rod; this second rod is lifted by a
connecting rod operated by a crank arm keyed to the excentric shaft
before mentioned. When the sliding tooth is brought into contact with
the tappet on the weighted rod that rod will be raised, and it will allow
the weighted chain to pull round the chain wheel and slide back the
pawl over the ratchet teeth. As soon however as the sliding tooth has
attained a given elevation it will be withdrawn by a tumbler action, and
the weighted rod being now released it will fall, and pulling over the
chain will eause it through the pawl to pull round the chain wheel shaft
and give rotary motion to the gearing before mentioned, and thus the
throw of the crank arms that operate the plunger bar will be obtained,
as will also the throw of the crank that operates the levers for sliding
the blocks in the face of the pressing slide, as above described. Before
however these motions can take place it is requisite to release the
longitudinal shaft at the back of the machine, which shaft is locked by
a bolt that enters a notched cam or plate keyed to the shaft. The bolt
slides in a fixed guide, and it is jointed to a looped rod which terminates
in a catch. Within the loop works an excentric which is keyed to a
longitudinal back shaft. This excentric is connected by a link and
crank arm to a crank pin, which being rocked by a hand lever moves
the excentric into a position that will tip the looped rod and bring its
catch within reach of a cam on the excentric driving shaft; when,
therefore, this cam comes round and acts upon the catch it will lift the
looped rod and thereby draw the bolt. Keyed on the back shaft are
other excentrics, and pendent from these excentrics are rods which carry
a presser bar; this bar slides in fixed guides, and it is provided with
horizontal prongs or fingers, which press upon the plate and hold it.
firmly ready for the descent of the punches. Before the plate is fed
forward the prongs or fingers are raised by the excentric to relieve it of
their pressure, which is due partly to the weight of the bar and partly to
a weighted rack bar, which gearing into a pinion on the excentric back.
shaft gives the shaft a motion the reverse of that it receives from the

page_text: hand. lever. By means of a tappet on the rack bar a cam on the
excentric driving shaft lifts that bar and thereby releases the excentric
back shaft from its weight, or pressure. The feed. is effected while the
punches are depressed and in the plate.