Improvements in Mechanism for Shearing and Threading Pipes.
Year: 1896

page_text: Date of Application, 8th Dec., 1896-Accepted, 13th Mar.. 1897
COMPLETE SPECIFICATION.
Improvements in Mechanism for Shearing and Threading Pipes.
1, THOMAS BRADBURY NUTTALL, Manager, residing at No. 3309 Ward
Street, in Pittsburg, in the County of Allegheny, State of Pennsylvania, and
United States of America, 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 :-
-
The invention described herein relates to certain improvements in pipe shears,
and has for its object a construction whereby the pipes can be easily and quickly
placed in position, and the ragged or scrap ends thereof rapidly cut off. In general
terms, the invention consists in the construction and combination substantially as
hereinafter more fully described and claimed.
In the accompanying drawings forming a part of this specification,
Figure 1 is a front elevation of my improved machine; Fig. 2 is a sectional
elevation of the same;
Fig. 3, is a transverse section of the revolving drum, the plane of section being
indicated by the line III-III, Fig. 2;
Fig. 4, is a rear end elevation of the machine; and
Fig. 5 is a detail view, showing the cutters for grooving or threading pipe.
In the practice of my invention, I provide a suitable base or frame 1, having
concave seats adapted to form bearings for the journals 2 of the rotating drum 3.
The rotating drum is held within its bearings in the base by cap plates 4. On the
drum about midway of its length is secured a circular toothed rack 5, adapted to
intermesh with the pinion 6, on the driving shaft 7, which is mounted in suitable
bearings on the brackets 8, attached to the sides of the supporting base 1. Bars 9
are arranged diagonally across the drum at both ends thereof, and between these
guide rods are arranged the shear shafts 11 and 12. These shear shafts are
provided near their front ends with wings 10, which are adapted to overlap,
.and through these wings is passed a pivotal pin 13. The ends of this pin are
arranged in blocks adapted to slide in slots in the vertical bars 9, at the front
end of the machine. Threaded bolts 14 and 15 have one end secured to the upper
shear shaft 11 and project up through a plate 16, secured between the bars 9, at
the ends of the drum. On the threaded bolts are screwed nuts 17, whereby the
shear shafts may be raised and lowered as desired. The rear end of the shear
shaft 12 is yieldingly supported in proper relation to the shaft 11 by means of
springs 24, which have their lower ends connected to a bar 25 passing under the
shaft 12, while their upper ends are connected to a bar 26 attached to a threaded
rod 27, projecting up through the plate 16.
On the front ends of the shear shafts are loosely mounted rotating cutters 18
and 19, the cutter 18, which is adapted to fit within the pipe to be sheared, is
preferably formed with a flat bearing face, while the cutter 19, is bevelled as
shown, so that in operating on a pipe it will be forced towards the cutting edge of
the cutter 18. On the rear end of the shear shaft 11 is loosely mounted a disc 20,
preferably formed with a transversely convex periphery, and on the rear end of
the shear shaft 12 is mounted an eccentric 21, having a transversely concave
periphery. On the eccentric 21 is secured an operating handle 22, which as
the drum rotates, will be carried against a stationary stop 23, on the supporting
frame, and held from rotation with the drum until the eccentric 21 shall have been

page_text: shifted to such an extent that its point of greatest eccentricity will bear against
the periphery of the disc 20. The handle 22 or its stop 23, are so constructed and
arranged that when the eccentric has been shifted to the point stated, the handle
will be shifted from the stop and will thereafter move with the drum. In order to
prevent an accidental misplacement of the eccentric from its adjusted position, a
recess or flattened portion is formed in its periphery at the point of greatest
eccentricity for the reception of the edge of the disc 20, as shown in dotted lines in
Fig. 4. This adjustment or shifting of the rear end of the shear shaft 12 away
from the shear shaft 11, will force the cutters at the front ends of said shafts
towards each other until the shear edges will overlap.
In using my improved machine, the shear shafts are first adjusted towards or
from the center of the drum until a pipe fitting over the upper shear shaft or its
cutting disc, and bearing against the flat bearing periphery thereof, will have its
axis in line with the axis of the rotating drum. A pipe is then slipped over the
projecting end of the shear shaft 11, and the drum rotated. As the drum rotates
the handle 22 will be brought into engagement with the stop 23, whereby, on the
continued rotation of the drum shifting the eccentric and forcing the cutter on the
lower shear shaft towards the cutt on the upper shear shaft. By the continued
rotation of the drum these cutters are carried around the pipe and its scrap end
removed. It will be understood that during the operation of these shears, the pipe
is held stationary by any suitable form of pipe clamp or vice.
By placing a flat, plane-faced disc 28, on the shear shaft 11 and a disc 29
provided with a series of spirally arranged cutting ribs on the shaft 12, suitable
external screw threads may be formed on the pipe.
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:
1. In a pipe shear, the combination of two cutters, one of which is adapted to
project into the pipe to be cut, means for adjusting the cutters towards and from
each other, and means for moving the cutters in concentric circles, substantially
as set forth.
2. In a pipe shear, the combination of a rotating drum, two cutters adjustably
mounted on said drum, one of said cutters being adapted to project into the pipe to
be cut, and means for shifting the cutters towards and from each other, substantially
. as set forth.
3. In a pipe shear, the combination of a rotating drum, two shear shafts pivotally
connected near their front ends and adjustable radially of the drum, cutters mounted
on the front ends of the shear shafts, and means for forcing the rear ends of the
shear shafts apart, substantially as set forth.
4. In a pipe shear, the combination of a rotating drum, two shear shafts
pivotally connected near their front ends and adjustable radially of the drum
cutters mounted on the front ends of the shafts, and means actuated by the
movement of the shear shafts for forcing the rear ends apart, substantially a
set forth.
I
5. A machine in accordance with either of the preceding claims but with
threading tools such as are shown in Figure 5, substituted for shearing tools.
Dated, at Pittsburg, Pa., U.S.A., this Sixteenth day of November
Witnesses :-
DARWIN S. WOLCOTT.
F. E. GAITHER.
THOMAS BRADBURY NUTTALL.