IMPROVEMENTS IN MACHINERY OR APPARATUS FOR MAKING BOLTS AND RIVETS
Year: 1858

page_text: 1706
application for Letters Patent was not given within the time prescribed
by the Act.)
PROVISIONAL SPECIFICATION left by John Henry Johnson at the Office
of the Commissioners of Patents, with his Petition, on the 18th February
1858. A communication from Jean Baptiste Fondu and Emile Boin.
I, JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of
Middlesex, and of 166, Buchanan Street, in the City of Glasgow, North
Britain, Gentleman, do hereby declare the nature of the said Invention for
IMPROVEMENTS IN MACHINERY OR APPARATUS FOR MAKING BOLTS AND RIVETS," a
communication from Jean Baptiste Fondu and Emile Boin, foreigners resident
abroad, to be as follows:-
This Invention relates to an improved combination of machinery or appa-
ratus for pressing bolts and rivets either hot or cold, and to a peculiar safety
apparatus for throwing the machine out of gear when the strain upon it
becomes unduly great. The whole of the mechanism is carried on a cast-iron
bed plate or standard placed horizontally, the main driving shaft being carried
in bearings at one end of the bed plate and the feeding mechanism at the
opposite end. The cam shaft is parallel to the driving shaft and receives
motion therefrom by means of a small spur pinion peculiarly fitted on to the
main shaft, and gearing into a large spur wheel keyed on to one end of the
cam shaft. The small pinion is secured to the driving shaft by means of bolts
or pins, against which bear two cutting plates, so that on any undue resistance

page_text: being offered to the movements of the machine the plates will cut off the
holding bolts or pins and thereby release the pinion, which will then turn
loosely upon the shaft, and consequently effect the stoppage of the machine
before any damage can be accomplished.
The material to be formed into bolts or rivets is fed into the machine in a
hot or cold state in the form of long lengths of bars of a circular section,
which bars are fed forward to the dies by being passed between a pair of
grooved feeding rollers, actuated intermittantly by a pall and ratchet wheel
movement driven by a suitable cam on the cam shaft. The pall is actuated
directly by a slotted crank or arm, and the connecting rod is capable of adjust-
ment therein, so as to give a greater or less stroke at each revolution of the
feed cam, whereby the length of material fed in at every stroke may be
regulated according to the length of bolt or rivet to be produced. A piece
of the proper length is first cut off from the bar by means of suitable shears
worked by toggle joints on either side of the machine, and these toggle joints
are actuated by rods worked from suitable cams on the cam shaft; by the
time the length is cut off it is firmly held between a pair of slides, also worked
from the toggle joints above referred to, and these slides hold the short length
of bar during the time it is being operated upon by the die which forms the
head. This die is carried by a slide, which is moved forward to give the
required pressure by means of a bent lever actuated by a cam on the cam
shaft, and after forming the head it is drawn back again by a rod connected
to another cam on the same shaft; the holding slides are now opened by
means of a short lever acted upon by a spring, and the finished bolt or rivet
is pushed forward and falls out by the advance of the end of the bar, which is
now brought forward by the feed motion in readiness for a repetition of the
operations above described. Suitable arrangements are employed for regulating
the pressure of the dies, and the machine may be constructed with two or
more sets of dies and attendant mechanism, so as to manufacture any desired
number of bolts or rivets at one time.