Improvements in Apparatus for Cutting Metal Joists, Bars, or the like:
Year: 1894

page_text: Date of Application, 17th Sept., 1894-Accepted, 24th May, 1895
COMPLETE SPECIFICATION.
Improvements in Apparatus for Cutting Metal Joists, Bars, or
the like:
I, CARL HOPPE, of Garten-Strasse 9-12 Berlin in the Empire of Germany, 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:-
:
In apparatus for cutting or shearing I or channel iron joists or bars hitherto
known only one of such joists, of a certain profile in section, and of a given size,
can be cut with one and the same set of cutters or shears, in consequence of which
a great number of different sets of cutters for the various sections of joists are
required.
This apparatus for cutting I and other joists, or bars, has for its object to enable
one and the same set of cutters to be used to cut I-joists, etc., of different sections.
Thus, taking for example 32 of the commonest and most frequently employed
sections of I-joists (i.e. from 80 to 500 millimetres in height); with my improved
apparatus only 4 different sets of cutters would be needed; whereas with the
apparatus previously known 32 different sets would be necessary.
The accompanying drawings illustrate the apparatus as used for cutting I-joists;-
Figures 1, 14, 1, and 1° relate to the apparatus for cutting one of the smallest
joist-sections for this set of cutters (e.g. 80 millimetres in height) before the
cut; while
Figures 2, 24, and 2B, show the same, after the cut;
Figure 3 illustrates the arrangement for cutting one of the largest joist-sections
for the same set of cutters, (e.g. 130 millimetres in height) before the cut; and
Figures 4 and 44 show only the positions of the cutters before and after the cut,
respectively.
This apparatus consists of 3 symmetrical pairs of cutters arranged to slide in
suitable grooves in the cutter-holders, i.e. in all 6 cutting blades, A1, A2, B¹, B³,
C1, C2, whereof the external pair, A¹ A², are pressed inwards and operate upon
the flanges of the joist from outside and in opposite directions respectively; and
the inner 2 pairs of cutters B¹ B and C C² whereof each separate cutting blade
is adapted to cut into one of the 4 inner right-angles (formed by the two flanges and
central web of the joist) and has its two cutting edges forming a right angle, are
pressed in a diagonal direction so as to operate simultaneously upon the two sides
of the web and the 4 inner surfaces of the two flanges, in a contrary direction to
each other centrally and to the first pair A¹ A³, outwardly; and thus all the
3 pairs, (or 6 cutting blades) are pressed simultaneously against the entire profile or
outline of the joist, acting severally in opposite directions, each to each, so as to
effect the cut, the whole of the twelve cutting edges meeting or nearly so in the
three axial lines of the web and flanges of the severed joist (all as shown in
Figures 2 and 4B) after the cut.
The cutting with one and the same set of cutters of I and other joists or bars of
different sections (viz. I-joists, 80, 90, 100, 110, 120 and 130 millimetres in height)
s attainable by reason of the special arrangement of the cuts, the special directions
of movement of the various cutters, and the sliding cutter-holders.
2
Of the 4 inner right-angled cutting blades B1 B2, C1 C2, the cutting edges bo³,
,,, which operate upon opposite sides of the web of the joist (i.e. as shown
1
2

page_text: .
.
in Figure 1, upon the upper and under sides) are, like these web-surfaces,
horizontally arranged; on the other hand, the cutting edges b¹³, c¹² of those
blades, as well as the corresponding cutting edges at a,, and a² a of the outer
cutters A A respectively do not stand vertically i.e. at right angles to the
horizontal cutting edges above named but are slightly out of the perpendicular,
slanting in a direction parallel to the line of bi-section of the angle formed
between the outer and inner flange-surfaces of the joist, and having therefore an
inclination to the vertical of about 7 per cent. (or 6-3 degrees) i.e. to the outer
surface of the flange; inasmuch as in all I-joists, of whatever section, the
inclination between the inner and outer flange-surfaces amounts to 14 per cent.
Consequently the following relations of parallelism subsist between the various
- cutting edges above named; a' || b¹² ; q² || c³² ; a¹ || c²; a² || b³.
+
As already stated, these 6 cutters A¹ A B B C C are not fixed, but are
arranged to slide in grooves h¹... ... (Figures 1, 1B and 3) in the cutter holders H¹
H', H H. These 4 cutter holders are adapted to slide transversely to the joist
in the head of a press or fixed in the press-plate connected with the plunger of a
hydraulic press, so that e.g. the lower cutter-holder H'H' is pressed against the
upper cutter-holder H¹ H³, or vice versa.
The inner 4 angle-cutters B1 B2 C1 C2 have each pressure-surfaces f¹ fl. .f2 f...
arranged at an angle of 45 degrees to their cutting edges, as shown in Figure 4,
each such diagonal pressure-surface corresponding to and actuated by the similar
pressure-surfaces F' F¹... F' F'... (Figure 1B) of the cutter-holder grooves h¹...
hh, so that the angle-cutters B₁ C₁ and B² (³, under the influence of the
vertical pressure P' P¹ (or P P) upon the oblique pressure-surfaces above. named,
are consequently pressed in the direction of the resultant force RR (Figure 4)
i.e. obliquely (or in this case at an angle of 45 degrees) outwards and downwards,
simultaneously; that is to say, outwards, against the inner surfaces of the flanges,
and downwards (or upwards) against the opposite sides or surfaces of the web, of
the joist to be cut; while, at the same time the outer cutters A¹ A³, under the
influence of the said vertical pressure P¹ P₁ (or P P) acting upon the diagonal
pressure-surfaces f f f ... (Figure 4) of A¹ A2 by means of the similar
pressure-surfaces F¹ F¹.
FF...(Figure 1B) of the grooves h¹ h¹... h² h² in the
cutter-holders H'H' H2 H2, are thrust inwards in a horizontal direction (towards
the corresponding inner angle cutters) against the outer surfaces of the flanges of
the joist to be cut. Thus, these 3 pairs of cutters severally opposed to each
other, a'' and a³ ³, a c¹ and a² c², bc and bc, are driven against each other
and through the metal of the joist or bar over the entire outline of the section, so
as to effect the required severance, and to leave the 6 pairs of cutting edges in
close contact (or nearly so) on the completion of the cut, in such manner that the
severed joist-ends are clean and free from any disfigurement.
The small diamond-shaped central portion Figures 2 and 44 of the web
remaining uncut by the blades is of such comparatively insignificant dimensions
that its severance is naturally superinduced by the completion of the cut.
For the purpose of preventing the cutters from falling out of the cutter-holders,
each of them is held in place by a pin D pressed upon by a spring F° as shown in
Figures 14, 1°, which pin does not however present any hindrance to its sliding
motion in the groove.
As shown in Figure 3, in cutting I-joists of various sections with the same set
of cutters as described above, it is necessary to employ intermediate cutters
(between the angle-cutters) to correspond to the extra height of the joist i.e. the
extra length in the centre of the web, for which purpose suitable cutter-holders
with dove-tail notchess (Figures 14 and 2ª) must be inserted in the press-head or
in the press-plate of the hydraulic press.
For cutting T-iron of different sections with the same apparatus i.e. with one
and the same set of cutters, only a half set of cutters viz. A B C¹ or A² B'C'
need be used. It may, however, be remarked that there is nothing to prevent the
use of the complete set of cutters upon a couple of T-irons of like section (these

page_text: being laid e.g. web to web with the flanges outwards, as if in fact they were au
I-joist slit in two longitudinally by a cut along the centre of the web).
Inasmuch as, also, the inclination of the inner to the outer flange-surface is
invariably 14 per cent., independent of size, in both [-iron and L-iron, these may
be cut upon the same principle, only with suitably arranged cutters; for in case of
the C-iron, for instance, on the outer flat side of the web, two straight cutters
would be pressed vertically against the web.
For cutting L-iron, similarly, only one pair of cutter holders H'H' or H'H',
with their cutters would come into operation, in a manner analogous to that of the
relation between the cutting of the I-joist and that of the T-iron.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed I declare that what I
claim is ;-
1
1. An apparatus for cutting metal joists or bars of ITL channel or other
section comprising an outer pair of movable or sliding cutters such as A' A³ pressed
against the piece to be cut with their cutting edges operating upon the outer flange-
surfaces of the joist or bar and inner movable cutters such as B₁ C¹ B³ C² sliding
simultaneously diagonally at an angle of 45 degrees up and downwards as well as
outwards and having their cutting edges b₁₁cob co directed against opposite sides
of the web of the joist or bar while their edges b₁ c' b c operate upon the inner
flange-surfaces in combination with separate movable cutter-holders such as H' H¹
HH sliding in the direction transverse to the piece of metal to be cut and
corresponding to the height thereof and provided with corresponding oblique
pressure-surfaces and grooves for the cutters in which grooves the cutters are
adapted to slide for the purpose of cutting with one and the same set of cutters
I and other joists or bars of different sections substantially as described and
illustrated in the accompanying drawings.
2. An apparatus such as described in Claim 1 for cutting metal joists or bars of
I or other section wherein the cutting edges operating on the outer and inner
flange-surfaces of the metal to be cut are inclined at an angle from the vertical
equivalent to one-half of the angle of inclination between such outer and inner
surfaces i.e. about 7 per cent. (or 6.3 degrees) so as to effect a complete severance
of the flanges of joists or bars of different sections with one and the same set of
cutters substantially as described.
3. An apparatus such as described in Claim 1 for cutting metal joists or bars of
I or other section wherein separate cutter-holders sliding towards each other in a
direction transverse to the metal to be cut and provided with corresponding oblique
pressure-surfaces for the cutters are arranged in such manner as to secure a
corresponding movement of the cutters from opposite directions towards and
against each other substantially as described.
Dated this 17th day of September 1894.
W. P. THOMPSON & BOULT,
Agents for the Applicant.