AN IMPROVED INSTRUMENT FOR CUTTING SCREW THREADS ON TUBES AND FOR CUTTING OFF LENGTHS THEREOF
Year: 1877

page_text: LETTERS PATENT to Gerard Wenzeslaus von Nawrocki, of the Firm of J. Brandt
and G. W. von Nawrocki, Civil Engineers and Patent Agents, of No. 2, Koch
Strasse, Berlin, in the German Empire, for the Invention of "AN IMPROVED
INSTRUMENT FOR CUTTING SCREW THREADS ON TUBES AND FOR CUTTING OFF
LENGTHS THEREOF." A communication by Carl Johann Friedrich Neuber
and Johann Carl Julius Vernimb, both of Hamburg, in the German Empire,
'
PROVISIONAL SPECIFICATION left by the said Gerard Wenzeslaus von
Nawrocki at the Office of the Commissioners of Patents on the 10th August
1877.
GERARD WENZESLAUS VON NAWROCKI, of the Firm of J. Brandt and G. W. von
Nawrocki, Civil Engineers and Patent Agents, of No. 2, Koch Strasse, Berlin, in
the German Empire. "AN IMPROVED INSTRUMENT FOR CUTTING SCREW THREADS
ON TUBES AND FOR CUTTING OFF LENGTHS THEREOF." A communication by Carl
Jóhann Friedrich Neuber and Johann Carl Julius Vernimb, both of Hamburg, in
the German Empire.
The present Invention relates to an apparatus for cutting screw threads on tubes
of different diameters by means of one and the same pair of dies, and after completing
this operation, cutting off the end of the tube to the length required.
For this purpose two dies are employed, of elliptical form, so that for tubes of
different diameters, different portions of the dies are brought into operation. The
one die is fixed by screws in a curved slotted jaw, and has a handle screwed to its
outer end for turning the instrument. The other die fits with a dovetailed projection
into a slide that is moved up and down an arm on one side of the said jaw by means
of a screw screwing through the end of the arm, and secured in a boss on the side of
the slide that enters a slot in the said arm, the end of the screw having a spherical
head which is held in a spherical socket, formed partly in the boss, and partly in a

page_text: separate piece fixed to the boss by a screw. The slide is hollow, and in it is
a cutting blade for cutting off the tube, for which purpose it is protruded through
the slide and through a hole in the screw die thereon by means of a screw working
through the end of the slide.
A simple flat cutter may be used in place of the second screw die. The first-
named screw actuating the slide is extended to form a second handle to the
instrument, and both screws have transverse holes for the insertion of spikes for
turning them.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Gerard Wenzeslaus von Nawrocki in the Great Seal Patent Office on
the 9th February 1878.
GERARD WENZESLAUS VON NAWROCKI, of the Firm of J. Brandt and G., W. von
Nawrocki, Civil, Engineers and Patent Agents, of. 2,, Koch Strasse, Berlin, in
the German Empire. "AN IMPROVED INSTRUMENT FOR CUTTING SCREW THREADS
ON TUBES AND FOR CUTTING OFF LENGTHS THEREOF." (A communication by Carl
Johann Friedrich Neuber and Johann Carl Julius Vernimb, both of Hamburg, in the
German Empire.)
This instrument is a combined screw stock and tube cutter, and it can
can by a
very simple manipulation be changed from one instrument into the other.
In the accompanying Sheet of Drawings this Invention is shown in one half its
full size.
Figures 1, 2, 3, 4, 5, and 6, show the instrument capable of cutting threads of
bolts or screws up to 2 inch diameter, and of cutting off lengths of tubes up to the
same diameter.; while Figures 7 and 8, show upon the same scale a similar
instrument suitable for cutting threads and tubes of small size.
Figure 1 is a side elevation of the instrument as a screw stock; Figure 2, a front
sectional view along the line a, b; Figure 4, a section along the line c, d,. Figure 5,
a section along the line e, f; and Figure 6, a ground plan... ..
i.
Figure 3 is a side elevation in section of the instrument arranged as a tube
cutter; Figure 7 is a side elevation of the instrument for tubes of small diameter;
and Figure 8, a section of the same along the line g, h.
To the frame A of the instrument the tool holder B is attached, movable in a
slot of the frame by means of the screw C, which is constructed in one piece with
handle D. The die L, specially serving as a guide, is fastened to the upper curved
part of the frame A, by means of the screw bolts E, F, and in the large size instru-
ments it is furnished with a handle G, as shown in the Drawing. In the small size
instruments this handle can be dispensed with. The cutting die K is fastened to
the tool holder by means of a projection, which is pushed into the opening s of the
holder. The end of this projection is furnished with a semicircular boring,..and.is
slipped over the ball-shaped end of the screw H, in a manner similar to that
shown in Figure 3 of the tube cutter. The die L is of elliptical shape, in
consequence of which threads of different diameters can be cut with the same pair
of dies

page_text: For cutting threads the tube is brought into the opening J, and kept between
the pair of dies by means either of the screw H or the screw C. By turning the
instrument around the tube, and by means of the pressure of the screw H or the
screw C, the thread is produced.
For cutting off lengths of tubes the die L is removed from the instrument, and
instead of the cutting die K, a cutting tool M is fastened within the tool holder B,
in the manner shown in Figure 3 of the accompanying Sheet of Drawings. The
tube is brought into the hollow end of the frame A, and by pressing the
edge of the tool M. against the surface of the tube by means of either one
or other of the screws H or C, and by turning the instrument the length is
cut off.
If preferred, edge rollers may be placed on the bolts E, F, which will assist the
tool M in the operation of cutting.
Figures 7 and 8 show the instrument for small size tubes. The die L is without
a handle, and may be formed exchangeable as a die on both sides, either for screws
of different or of the same diameter.
In all other parts this instrument is identical with the one before described,
and the same letters correspond with the same parts of both size tools.
And having now described the nature of the said Invention and in what manner
the same is to be performed, I declare that I claim, the improved and combined
instrument forming a screw stock and tube cutter as herein-before described, and
substantially as shown in the accompanying Sheet of Drawings.
In witness whereof, I, the said Gerard Wenzeslaus von Nawrocki, have here-
unto set my hand and seal, this Second day of February, One thousand
eight hundred and seventy-eight.
GERARD WENZESLAUS V. NAWROCKI. (L.S.)