Improvements in Rivetting and Pressing Machines.
Year: 1896

page_text: Date of Application, 14th Apr., 1896-Accepted, 23rd May, 1896
America, Manufacturer.]
Improvements in Rivetting and Pressing Machines.
I JAMES JOHNSON of 4 Clayton Square, Liverpool in the County of Lancaster,
Patent Agent, do hereby declare the nature of this 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 relates to improvements in machines for rivetting by pressure, or
in machines applying pressure for other purposes in such manner that the greatest-
pressure is exerted at or near the end of the stroke, and although in this
Specification I describe the invention particularly as applied to rivetting machines,
I do not intend to limit myself thereto, but wish to cover its use for any purpose
for which it may be adapted.
DESCRIPTION OF THE DRAWINGS.
Figure 1 shows in side elevation a rivetting machine constructed in accordance
with my invention; Figure 2 is a front elevation thereof; Figure 3 is a horizontal
section on the line -, of Fig. 1.
Like symbols indicate like parts in each.
In the drawing, A represents the frame of a rivetting machine. B, is the
rivetting plunger which moves to and fro in a suitable guide or hub C on the
frame A. D. E, are the rivetting dies, the moving die D being fixed to the plunger
and the stationary die E being fixed to the frame.
The motor by which the plunger is actuated consists of a cylinder N having a
reciprocating piston and a piston-rod M operated by steam, compressed air, or
water; or any other type of motor, such as an electric motor, or even hand-levers for
giving longitudinal motion to the piston or other rod M may be employed. N' is a
valve governed by a hand-lever N2 by means of which the operation of the motor
may be controlled. Power is transmitted from the motor to the die plunger
through a lever or bar F pivotted at one end at G to the machine frame, and at
the other end pivotted to the upper end of the plunger B by means of a pin H,
fitting in a somewhat elongated hole. At the end of the piston-rod M there is
preferably an anti-friction roller L, which rides upon the upper side of the lever F,
and as this lever is inclined relatively to the path of motion of the roller when the
plunger is in its most elevated position, as shown in the drawings, longitudinal
motion of the piston-rod will cause the roller to act thereon with a wedge-like
action and to turn the lever on its pivot G, thereby depressing the plunger B, and
moving the die D towards its cempanion die E. To hold the roller L in contact
with the lever during such motion of the piston-rod, and to take up the strain of
the work, I employ a swinging arm K, pivotted at one end to the piston-rod at the
axis of the roller L, and pivotted at the other end at J to bars or posts I, I, which
extend from the frame A and in effect constitute part of the frame. By reason of
the use of the said swinging arm, when the piston-rod is projected, the roller at its
tend moves in the arc of a circle shown by dotted lines, and the thrust thereon is
taken up by the swinging arm and lost. O, is a lifting bar connecting the arm K

page_text: at a point to the lever F at the point Q. This lifting bar, is divided and fitted
with a spring p so as to have some loose motion, the purpose being that when the
piston rod is retracted, the retraction of the swinging arm K acting through the
rod O will lift the lever F.
The operation of the machine is as follows:-The work to be rivetted is
interposed between the dies D, E, and the parts being in the position shown by full
lines in Fig. 1, the cylinder N is operated so as to project the piston rod M. The
roller L moving along the surface of the lever F will force it down, thus moving
the plunger B within its guide and pressing the moving die upon the rivet with
great pressure. The dotted lines in the drawing and the reference figures designated
by the prime (1) mark, show the parts in the positions which they occupy at the end
of the stroke.
The action of the inclined lever F with the end of the piston-rod rolling or sliding
in contact there with is such that the speed of motion of the plunger decreases as
the plunger advances, and that the slowest motion and the greatest pressure is
exerted upon the work at the end of the stroke when the rivet is being finally upset
and shaped, and when the greatest pressure is needed. On the return stroke of the
piston, the lever F is lifted by means of the lifting-rod O'and the parts are thus
restored to the positions shown in the drawing, but although the lifting rod is a
convenient device for this purpose, it is not essential, for the same work can be
perforined by a spring, weight, or other counterbalance acting upon the lever.
The advantages of my invention are many and will be apparent to those skilled:
in the art.
The apparatus which I have described is simple in construction; compact,
durable, and easy to maintain in working order, and it affords means for rivetting
in the most effective manner, giving the greatest pressure at the time when it is
most needed, and distributing the strains of work upon the proper parts of the
nachine.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
First. The improvements in rivetting and pressing machines substantially as
herein set forth.
Second. A machine for pressing or rivetting, comprising a plunger which carries
the moving die or tool, mechanism such as a cylinder having a reciprocating part
adapted to impart motion to the plunger, a lever connected with the plunger and
inclined to the path of motion of said reciprocating part and in sliding contact
therewith, and a swinging arm pivotally connected to the frame of the machine
and connected also with said reciprocating part for holding the latter to its working
contact with the lever, substantially as described.
Third. A machine for pressing or rivetting, comprising a plunger which carries
the moving die or tool, mechanism such as a cylinder having a reciprocating part
adapted to impart motion to the plunger, a lever connected with the plunger and
inclined to the path of motion of said reciprocating part and in sliding contact
therewith, a swinging arm pivotally connected to the frame of the machine and
connected also with said reciprocating part for holding the latter to its working
contact with the lever and a roller bearing between said reciprocating part and the
lever substantially as described.
Fourth. A machine for compressing or rivetting, comprising a plunger which
carries the moving die or tool, mechanism such as a cylinder having a reciprocating
part adapted to impart motion to the plunger, a lever connected with the plunger
and inclined to the path of motion of said reciprocating part and in sliding contact
therewith, a swinging arm pivotally connected to the frame of the machine and
connected also with said reciprocating part for holding the latter to its working
contact with the lever, and a lifting rod or connection coupling the swinging arm
with the lever, substantially as described.

page_text: Fifth. A machine for pressing or rivetting, comprising a plunger which carries the
moving die or tool mechanism such as a cylinder having a reciprocating part
adapted to impart motion to the plunger, a bar connected with the plunger and
inclined to the path of motion of said reciprocating part, and in sliding contact
therewith, a swinging arm pivotally connected to the frame of the machine and
connected also with said reciprocating part for holding the latter to its working
contact with the bar, and a lifting-rod or connection coupling the swinging arm
with the bar, substantially as describe d