IMPROVEMENTS IN SCREWING APPARATUS
Year: 1883

page_text: LETTERS PATENT to Joshua Heap of Ashton under Lyne in the County of
Lancaster Engineers Tool Maker, for an Invention of IMPROVEMENTS IN
SCREWING APPARATUS
PROVISIONAL SPECIFICATION left by the said Joshua Heap at the Office
of the Commissioners of Patents on the 21st September 1883.
JOSHUA HEAP of Ashton-under-Lyne in the County of Lancaster, Engineers'
Tool Maker, "IMPROVEMENTS IN SCREWING APPARATUS
"
My Invention relates to screwing stocks and screwing machines wherein the dies
are advanced simultaneously towards the axis of rotation or the centre of the work
by the action of a hollow cone pressing all the dies inward simultaneously. In tho
said form of stock three or a greater or less number of dies slide in recesses formed
to receive them in the body of the stock the said stock body being recessed and
screwed to receive a hollow cone outwardly formed with a screw thread and so
arranged that as the said hollow cone is screwed further into the stock its inclined
face bearing upon the similarly inclined ends of the dies forces them simultaneously
inwards. To keep the dies in their several recesses a cap or plate is employed
which has hitherto been secured to the body of the stock by means of screws or
bolts. According to my Invention I dispense with the said means for fixing the
plate over the dies and secure it in position by means of the hollow cone. The
cone is in the form of a ring the outer periphery being screwed as aforesaid to
enter the stock body whilst the inner periphery consists partly of the inclined
conical face and partly of an upper screwed portion the screw thread being the
same in pitch as that on the outer periphery. The outer circumference of the cap
plate is also screwed to fit the interior thread of the cone ring so that as the hollow
cone is screwed into the stock body it engages also with the cap plate and retains
it in position. I preferably provide the cap plate with a projecting stud or catch
which enters a hole in the stock body and prevents the plate from turning with
the hollow cone. My Invention further relates to the steel dies used in screwing
and consists in forming them to cut both ways. This I effect by forming a diagonal
groove across the threads of the die so as to present a cutting face opposite or

page_text: nearly opposite to the centre of the work. Thus in screwing downwards the
cutting faces at the bottom of the dies will lead, and in returning the cutting faces
at the top will lead. In an arrangement of apparatus or stock for screwing pipes I
utilize the herein before referred to hollow cone to effect the chucking of the pipe.
The hollow cone screws upon the end of the chuck or guide bush and simultaneously
forces in sliding dogs which grip the pipe and hold it in a truly central position to
be acted upon by the dies.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Joshua Heap in the Patent Office on the 8th March 1884.
.
JOSHUA HEAP of Ashton-under-Lyne in the County of Lancaster Machine
Tool Maker IMPROVEMENTS IN SCREWING APPARATUS
"
My Invention relates to screwing stocks and screwing machines wherein the dies
are advanced simultaneously towards the axis of rotation or the centre of the work
This I accomplish by the action of a hollow cone pressing all the dies inward
simulataneously. In one form of stock three or a greater or less number of dies slide in
recesses formed to receive them in the body of the stock the said stock body being
recessed and screwed to receive a hollow cone outwardly formed with a screw
thread and so arranged that as the said hollow cone is screwed further into the stock
its inclined face bearing upon the similarly inclined ends of the dies forces them
simultaneously inward. To keep the dies in their several recesses a cap or plate is
employed. In ordinary stocks the corresponding part has been secured to the
body of the stock by means of screws or bots. According to my invention
I dispense with the said means for fixing the plate over the dies and secure it in
position by means of the hollow cone. My invention relates further to the steel
dies used in screwing and consists in forming them to cut both ways. This
I effect by forming a diagonal groove across the threads of the die so as to present
a cutting face opposite or nearly opposite to the centre of the work. In an
arrangement of apparatus or stock for screwing pipes I use a hollow cone to effect
the chucking of the pipe.
A cross
In Order that my invention may be fully understood I have attached hereunto a
sheet of drawings to which I will refer in this place. In the said drawings Fig: 1
represents a longitudinal section and Fig 2 a plan of a screwing stock constructed
in accordance with my invention. In the said Figs a is the body of the stock
which is formed or provided with suitable handles a¹ as is usual. The said body
is of circular formation and in it is formed a turned annular recess.
section of this recess is seen to the right hand in Fig: 1 wherein it will be seen
that the outer wall b is of cylindrical formation and the inner wall b₁ of conical
formation so that a truncated cone projects from the bottom of the recess. In the
wall 6 of the recess is formed a screw thread and a corresponding thread is formed
in the outer periphery of a ring c which is fitted to screw into the recess. A part

page_text: of the interior of the said ring is turned to form a hollow cone. In the centre of
the stock body is formed an opening to receive the bolt or body to be screwed as
is usual and into this opening project the dies d, d, d, which are fitted in slots
formed in the body that is to say in the aforesaid truncated cone. The outer ends
of these dies are beveled and rounded to suit the conical interior surface of the
ring c with which the said outer ends are in contact when the dies are in use the
said ring furnishing an abutment for the dies. In the ring c are formed holes c'
and a key provided with two or more studs adapted to enter such holes is employed
to turn the said ring or any other suitable provision for enabling the ring to be
turned may be made. It will be seen that when the ring is turned in the direction
which will cause it to advance into the recess the dies will all be thrust inward
simultaneously by the action of the conical interior of the ring upon the outer ends
of the dies and the said interior being turned to a true conical form the dies will
all be advanced toward the work to an equal extent. To retract the dies or to
permit them to move back from the work the ring c is turned in the direction
which will withdraw it to some extent from the recess. The conical formation of
the wall b of the recess is adopted in order to obtain longer bearings for the dies
than if the said walls were parallel with the outer wall 6 but I do not confine
myself to such formation. The slots in which the dies are placed are covered by
an annular plate or cover e which is formed with a screw thread on its outer edge.
A corresponding screw thread is formed at c in the ring c and these screw threads
correspond in pitch with the screw threads at b. The effect of this arrangement
is that the two sets of screw threads work in unison so that the ring c can be
turned in either direction without disturbing the cover e. When the ring is entirely
withdrawn the said cover is released so that it can be removed. To ensure the
cover being replaced in the correct position that will enable both sets of screw
threads to engage at the same time a stud or pin in the body of the stock or in
the cover enters a hole in the other part. This method of keeping the cover e in
place obviates the necessity for the use of small screws, which necessitate the use
of a screw driver or small key and which are liable to be lost and are easily
damaged and quickly worn out. To facilitate the removal and replacement of the
ring c I prefer to form it with a projecting edge which is milled or nicked so
that the ring can be turned when loose without the aid of a key. My improved
formation of the dies is illustrated in Figs 1 and 2 and especially in Fig: 1
wherein one of the dies is seen with a diagonal groove crossing the threads from top
to bottom of the cutting face of the die.. The two sides of this groove furnish two
cutting edges the novelty consisting in the inclination of the said groove whereby
when screwing downward the cutting faces at the bottom of the die will lead and
in returning or screwing upward the cutting faces at the top of the dio will lead.
The remaining Figs illustrate a form of apparatus adapted more particularly for
use in screwing pipes Fig: 3 being a longitudinal section. Fig: 4 a plan and
Fig 5 a cross section on the line in Fig 3. In this example the screwing stock a
is provided with a hollow boss in which is formed a screw thread which
corresponds in pitch with the thread which is to be produced upon the pipe or
work. The screw thread in the said boss engages with a corresponding thread
formed on the exterior of a tubular guide piece g which is clamped upon the pipe
or work. Two holding dogs or clamps h, h, are fitted to slide in slots in the
piece g and are thrust inward by means of a ring i. A part of the interior of
this ring is formed as a hollow cone as in the case of the ring c and a part of the
said interior is formed with a screw thread which engages with a thread formed on
the piece g. By turning the ring i so as to screw it further upon the piece g the
dogs h are thrust inward so as to clamp the guide piece upon the tube or work to
be screwed. When a tube is screwed with this apparatus the guide piece g ensures
the formation of a true thread. I do not confine myself to the use of two dogs
only as the apparatus might be fitted with three and if the guide piece g was
lengthened it might be provided with two sets of dogs so as to clamp the tube at
two places in its length. The stock so constructed may be used in the screwing of
•

page_text: bolts or rods or of work other than tubes. The method of setting up dies by
means of a conically shaped ring formed with a screw thread and advanced and
retracted by a revolving screwing motion is applicable in the construction of
screwing machines or of other forms of screwing apparatus than are illustrated in
the attached drawings.
Having Now fully set forth and indicated the nature of my said invention and
the manner in which I carry the same into practical effect I would have it to be
understood that I claim -
First. The combination of parts forming the screwing stocks constructed and
acting substantially as set forth and indicated hereinbefore and in and by the
accompanying drawings.
Secondly. In screwing apparatus setting up the dies by means of a ring formed
with an interior hollow conical surface and with an exterior screw thread and
seated in a screwed recess such ring being advanced by a revolving screwing
motion to set up all the dies simultaneously substantially as set forth and
indicated.
Thirdly. In screwing stocks or apparatus the ring c formed and acting upon the
dies substantially as and for the purpose set forth and indicated.
Fourthly. Cutting a diagonal groove that is to say a groove inclined with
respect to the axis of the work across the threads of each die. used in a screwing
apparatus substantially as and for the purpose set forth and indicated.
Fifthly. The method of keeping in place the covering plate of screwing stocks
by means of the screwed ring used to set up the dies substantially as set forth and
indicated.
And lastly. The screw ring formed with a hollow cone to set up holding dogs or
clamps substantially as set forth and indicated with reference to Figs 3, 4 and 5 of
the attached drawings.
In Witness whereof I the said Joshua Heap have hereunto set my hand - and
seal this fourth day of March in the year of our Lord one thousand eight
hundred and eighty-four
Signed, sealed, and,
delivered in the
presence of
EDWARD K. DUTTON
41 John Dalton St, Manchester.
(Agent for the Patentee)
JOSHUA HEAP. (L.S.)