CERTAIN IMPROVEMENTS IN SOLID DIES FOR SCREWING TUBES OR OTHER PURPOSES
Year: 1876

page_text: LETTERS PATENT to John Wells, of Wednesbury, in the County of Stafford,
Mechanical Engineer, for the Invention of "CERTAIN IMPROVEMENTS IN SOLID
DIES FOR SCREWING TUBES OR OTHER PURPOSES."
led the 27th February 1877, and dated the 30th August 1876.
PROVISIONAL SPECIFICATION left by the said John Wells at the Office of
the Commissioners of Patents on the 30th August 1876.
JOHN WELLS, of Wednesbury, in the County of Stafford, Mechanical Engineer.
"CERTAIN IMPROVEMENTS IN SOLID DIES FOR SCREWING TUBES OR OTHER PURPOSES."
My improvements in solid dics consist in giving a spiral or oblique direction to
the faces of the cutting threads, the internal circular die being divided into any
reasonable number of projecting spial faced threads Dies thus fashioned will cut
screws on the ends of tubes, bolts, or bars of iron or other metal with more regu-
lanty and expedition than can be effected by the ordinary dies with perpendicular
faces to the cutting threads.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said John Wells in the Great Seal Patent Office on the 28th February 1877.
JOHN WELLS, of Wednesbury, in the County of Stafford, Nechanical Engineer.
"CERTAIN IMPROVEMENTS IN SOLID DIES FOR SCREWING TUBES OR
PURPOSES"
OTHER
My improvements in solid dies consist in giving a spiral or oblique direction to
the faces of the cutting theads, the internal circular die being divided into any
reasonable number of projecting spiral faced threads Dies thus fashioned secured
in suitable stocks according to size will cut screw threads on the ends of tubes,
bolts, or bars of iron or other metals with more regularity and expedition than can
be effected by the ordinary dies, with perpendicular faces to the cutting threads as
now used, as will be perfectly understood by reference to the Drawings hereunto
annexed, which I will now describe.

page_text: five, or other divisional numbers may be used Fig 2 is a section of Figure 1 taken
through the dotted lines a and b. In this view I am enabled to show the oblique
or angular direction of the clearance ways, and in this lies the essential element of
my improvements; for instead of the clearance being perpendicular to the face of
the-die as in ordinary dies, the threads from their obliquity to the clearanco take up
their work of cutting the thread one after the other in the said operation, which is
a great advantage in the operation of screw cutting both in the beginning and con-
tinuance of the operation. The degree of obliquity here shown I have found to
answer well, notwithstanding it may be slightly increased or diniinished without
materially effecting the object of the Invention.
These dies may be applied to a corresponding square recess in my improved screw
stock, as here shown in Fig. 3, marked A The angular external ineasurement of
the die being preserved any number of such dies for various sized threads may be
applied to the same stock, and held in position by. the plate B, which being held by
the screw c permits the plate B to be turned around until the hollow & passes under
the head of the screw f. The handle parts of the stock C and D aie by preference
made of short lengths of tubing closed at the outer ends, and tapped in to the cast
part of the stock at g and h
Fig. 4 is a side view of Figure 3 with the plate B in position, showing the
circular socket E for receiving a loose socket, as shown separate in side and bottom
view at Fig. 5; the advantage of the use of this loose socket is simply that it may
be changed as the dies are changed, that its concentric hole as at F may be increased
or diminished according to the size of the tube or bar to be tapped, over which the
said loose socket freely works; this loose socket is held in the socket E, Figure 4,
by a thumb screw, as at k, or by other convenient' means The screw fextends, as
indicated by the dotted lines, through the stock, with the inner end tapped for
receiving the thumb screw m, which will afford means for holding the under side of
the head of the screw pin f down on the part B so as to prevent looseness. This
arrangement of the stock allows of any necessary progressive size of dies to be used
with it, but for screwing smaller or larger bars or tubes the stock and dies should
be apportioned in size to them, as will be well understood by artisans accustomed to
their use.
Having thus described the nature of my Invention, and the manner in which the
same may be carried into effect by artisans accustomed to the manufacture of such
kind of appliances, I wish it understood that the details herein described and set
forth may be varied without departing from the spirit and object of my Invention,
as for instance the dies and their corresponding recesses in the stock may be other-
wise shaped on the outer surface than the rectangular form here given, as they
may be of an octagon form or even rounded, provided they are shaped with pro-
jections or recesses, the said recesses or projections in the stock being of corre-
sponding shape for receiving them, but I claim as of my Invention the angular
cutting faces of the dies, ranging at any angle from 5° to 30°, and tho adaption of
such dies to the stock, as herein described and exhibited, without regard to the size
or proportion of such dies and stocks or attendant parts
In witness whereof, I, the said John Wells, have hereunto set my hand and
seal, this Twenty-fourth day of February, in the year of our Lord One thou-
sand eight hundred and sarrenty-seven
Witness,
GEORGE F. A. GRIFFIN,
Clerk to Mr. James S. Cockings,
17, Ann St.,
Birmingham.
JOHN WELLS. (LS.)