Improved Method and Apparatus for Cutting or Dividing Metal Bars or Rods.
Year: 1897

page_text: Date of Application, 28th July, 1897--Accepted, 29th Jan., 1898
COMPLETE SPECIFICATION.
Improved Method and Apparatus for Cutting or Dividing Metal
Bars or Rods.
I, HUGO JOHN, of the Firm of J. A. John, of Pilse 8, Erfurt, Germany,
Manufacturer, 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 :―
With previous devices for cutting or dividing iron bars or rods of round, square, or
other cross section, a bar to be divided has been laid upon a block a (Fig. 1) and the
dividing steel, such as a cutting or shearing plate b, has been moved in a straight
direction towards the bar to be divided. The movement of the cutting plate b has
been either rectilinear, as indicated in Fig. 1, or curvilinear, the cutting-plate b
being rotatable about a pin d by means of a crank. or eccentric c (Fig. 2) so that the
plate b has been rotated towards the block a in an almost straight direction-i.e. in
a direction quite or almost perpendicular to the bar to be divided.
The arrangement of a number of such cutting-holes in a circular arc about a
centrally rotated cutting-plate b so that wires of various thicknesses could be cut, is
also already known.
The cutting plate a has in all known constructions a cutting edge of a shape
similar to that of the cross section of the bar to be cut; it consequently acts only
by the pressure exerted upon it, and therefore a comparatively considerable force is
necessary to cut or shear the bar.
This invention consists of a method and apparatus for dividing iron bars of various
cross sections which, in consequence of a new principle of cutting or, rather, twisting.
off the bar, renders the work considerably easier. The method consists in that one
of the two cutting parts-i.e., either the cutting plate or the abutment-plate-is
rotated centrally in relation to the other part, but the cutting-hole is so arranged
that a point of its edge lies either exactly or nearly in the axis of rotation of the
movable plate or the axis of rotation lies inside the area of the cutting
hole.
On the rotation of the movable part the cutting edges in the two parts are gradually
shifted in relation to each other and press not only perpendicularly upon the bar to
be cut but also execute a drawing cut in a peculiar way. The part of the bar to be
cut off, which lies in the rotating cutting-part, participates in this rotation. The
bar to be cut is at the end to be divided off rotated about itself through a certain
angle-i.e. rotated relatively to the fixed part and therefore twisted off. In this
case there is, in addition, a drawing cut-i.e. the mode of action of the knife f (see
Fig. 3), which presses on the round body e to be cut and is moved forward at the
same time in the direction of the arrow, the body to be cut rolling forward
simultaneously and consequently rotating about itself.
This mode of operation differs essentially from that represented in Fig. 4, which
is known, being usual in book-binding, cutting-machines, and in which the cutter g
does, indeed, move obliquely in relation to the sheets h to be cut but is pressed
with its whole surface upon the sheets. In the method according to this invention,
on the contrary, the cutting surfaces of the cutting edge are continually
changing

page_text: The cutting parts are represented in Figs. 5 & 6 in front elevation and section
respectively..
A is the abutment-plate, and B is the cutting-plate, which rotates about itself
and which in the present case is constructed as a cylinder. B is rotated in the
direction of the arrow C. A and B are each provided with a hole D, which has
a cross section similar to that of the bar to he cut and into which the bar to be
divided is inserted. The hole D is placed eccentrically to the centre E of the
cylinder B and in such a manner that it lies either with a point of its periphery
in the axis of rotation E or with such a point only a few millimetres away or the
axis of rotation lies within the hole D. In the initial position of the hollow cylinder
the cutting-hole D of the cylinder B forms a continuation of that of the abutment-
plate A. If, now, the cylinder B.be rotated in relation to the plate A and in the
direction of the arrow C (see Fig. 7), the following will be the effect :-
"The point 1 of the cutting plate B, which at first was opposite to the point 1 of
the abutment-plate A, after a certain time reaches 1+, the semicircle 1, 2, 3 of the
plate B reaches 1+, 2+, 3+, the cutting edge consequently moves the quicker the
farther it is from the centre E, and the cutting surfaces therefore execute a drawing
cut upon the bar to be cut.
In addition to the rotation of the article to be divided in the sense of the arrow C
by the cylinder B, there is also a rotation of the bar-end to be divided off, about
itself or about a point 3 of its periphery in relation to the stationarily held part of
the bar, whence results the distortion of the fibres of the bar at the dividing-place,
and, consequently, the twisting-off of the required part of the bar.
It is therefore characteristic of this invention that the bar to be divided is held by
a cylinder B, whose cutting edges are in contact with the cutting plate A and is
centrally rotated, the cutting-hole D being located so eccentrically that the axis of
rotation Elies quite or nearly in its periphery.
A machine constructed according to this invention is represented in Figs. 8 and 9.
The plate A is fixed and in the machine shown it is adjusted so as to be exactly
concentric to the centre of the cylinder B by means of a wedge G that bears against an
angle-piece F. The cylinder B is centrally rotatable in a frame H and is secured to
a long lever J, whose rotation in the sense of the arrow is caused by mechanism that
will now be described.
On the pin K¹ there is rotatably mounted a cap K that receives a toothed detent-
rack L, which is rotatable at O on the hand-lever M, near the fulcrum N of the latter.
The rack L can be fixed in the cap K by means of pins P, but the detaining pins P
may be removed and the cap be then coupled with the rack L according to one
direction of movement by means of a detent Q. The mode of operation is consequently
as follows:-
When the rack L and the cap K are firmly coupled by the detaining pins P and
the hand-lever M is moved, the latter pulls the lever J in the lever-ratio
NM¹
NO
(the toothed rod L is a rigid connexion) and in consequence of this the hollow
cylinder B is rotated comparatively quickly.
In cutting thicker bars the detaining pius P are removed; the rack L can then
move relatively to the cap K and consequently the hand-lever M can be brought
repeatedly towards the lever J with the result that the lever J is gradually drawn
in the direction of the arrow in the figure. A detent R may be employed in
this case to keep the cylinder B home during its rotation-i.e., to prevent it from
rotating backwards during the cutting. The detent R engages in a curved detent-
rack S on an edge of one of the frames of the machine.
The adjustable stop T serves for determining the length to be cut off.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed I declare that what I
claim is-
1. A method for dividing or cutting bars or rods according to which a part of a bar ‹

page_text: to be divided is carried by a body B which has a cutting-hole and is rotated about
itself in relation to a fixed abutment-plate A, which also has a cutting-hole, the
arrangement being such that the cutting-hole of the body A is eccentric to the axis
of the body B and a point in its edge is located either exactly or almost exactly in
the axis of rotation, so that during the central rotation of the body B in relation to
the abutment-plate the cutting edges of both execute a drawing cut.
2. Apparatus for carrying out the method referred to in the preceding claim, in
which the cutting-plate A, provided with a hole D and cutting-edges, adjoins a hollow
cylinder B, which is guided centrally in the frame H, is likewise provided with a hole
and cutting edges, is progressively rotated by means of a lever-connexion J, L, M,
and therefore gradually changes the position of its hole in relation to that of the hole
in the cutting plate.
3. Apparatus according to Claim 2 in which a detent-rack L is adapted to be
disconnectably coupled, by means of detaining pins P, to a cap K mounted rotatably
on a lever J, and provided with a detent Q, so that by coupling the rack L with the
cap K by means of the pins P the lever J can be caused to have a quick forward
rotation, and by disengaging the pins P from the rack the detent Q will be caused to
engage therewith and will then allow the cutting plate B to have a slower forward
rotation.
4. Apparatus for cutting or dividing rods or bars constructed, arranged, and
operating substantially as herein before described with reference to and shown in
Figs. 8 and 9 of the accompanying drawings.
Dated this 28th day of July 1897.
For the Applicant,
W. LLOYD WISE,
46, Lincoln's Inn Fields, London, W.C., Chartered Patent Agent.