IMPROVEMENTS IN THE MANUFACTURE OF BIRD CAGES
Year: 1874

page_text: PROVISIONAL SPECIFICATION .left by Samuel Robotham at the Office
of the Commissioners of Patents, with his Petition, on the 15th
October 1874.
I, SAMUEL ROBOTHAM, of Birmingham, in the County of Warwick,
Manufacturer, do hereby declare the naturo of the said Invention for
“IMPROVEMENTS IN THE MANUFACTURE OF BIRD CAGES," to be as follows :-
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My Invention has for its object the puncturing of metal strips, and
threading wires therein. For this purpose I provide in a suitable frame
two pairs of rolls acted upon by an under roll or spindle, which
maintains a rotatory motion, but by a single spur at one end imparts an
intermittent motion to the two pairs of rolls-by-moving a spur wheel one
tooth (at each rotation), the spur wheel being keyed to one of the rolls,
the other three rolls receiving their motion therefrom: On the under
spindle, on which are also the fast and loose pullies at one end to
connect by band with the motive power, is fixed at the other an archi-
medean or screw shaped cam of the length the wires are required. This.
cam acts on a lever, to which are connected plyers for forcing the wire
forward. The cam draws the plyers back along the wire, and a weight
:

page_text: I
produces the forward motion. Moveable guides are placed to keep the
wire in a straight line.
The strips of metal being cut of a suitable width, one of the front
rolls, the top one by preference, has a shallow groove turned the width
of the strips. Another groove is turned in the centre, the edges being
left sharp for cutting. The fellow roll has projecting punches made to
fit the narrow groove in the opposite roll. The said punches are formed
to cut longitudinally, and force a loop, which by a few turns of the cam
spindle forces the strip of metal, so that a loop is brought opposite the
end of the wire, and the cam freeing the plyers the weight draws the
plyers and wire forward, and passes the said wire through the loop, and
so on through two more loops (by preference) formed in the same
manner. The wire is then cut off by a lever acted upon by a tooth on
the cam spindle. The intermittent motion of the rolls then passes the
wire that is cut off with the strips of metal in due course between the
other pair of rolls, which are so formed that they press the loop of
metal tight on the wire, and also emboss a pattern between the wires.
To facilitate the passing of the wires into the loops semi-conical guides
are placed opposite the said loops, which are lifted up to allow the wires
to pass on. The guides are held down by crank levers, which are acted
upon by the punches or other projections, so that when the ends of the
levers are pressed the guides are held down, and the projection passing
on at the next intermittent motion the levers are released, and the guides
rise up with a weight or spring.
Instead of the second pair of rolls for embossing and closing the sheet
metal loops on to the wires I sometimes use a stamp, the hammer of
which is raised by the cam lever in its backward motion from carrying
the wires through the loops.
The stamp hammer may be loosed and caught by the usual method of
a self-acting catch and releasing bar.
I prefer to form a solid base past the threading or sliding of the wire
for the stamping.
In order to keep the work straight after being stamped I provide a
plain or flat surface, and one or more hooks to a cross bar, which said
cross bar is acted upon when connected with the work by a weight
connected therewith by a chain or cord over one or more pullies. The

page_text: said weight is so distanced from a lever that when a desirable quantity
of work is made the said lever shall throw off the band from the driving
pulley.
There is also an apparatus similar to that used in weaving machines
connected with the strips of metal, so that when a strip terminates at
the rolls the driving band will be thrown on to the loose pulley.