A NEW OR IMPROVED MACHINE FOR FORMING ELBOWS OR BENDS IN SHEET METAL PIPES OR TUBES
Year: 1871

page_text: LETTERS PATENT to John Millward, of Curzon Chambers, Paradise
Street, Birmingham, in the County of Warwick, for the Invention
of "A NEW OR IMPROVED MACHINE FOR FORMING ELBOWS OR BENDS IN
SHEET METAL PIPES OR TUBES." A communication from abroad
by Charles Hoeller, of Cincinnati, Hamilton County, State of Ohio,
Tinited States of America
-
PROVISIONAL SPECIFICATION left by the said John Millward at the
Office of the Commissioners of Patents, with his Petition, on the
16th March 1871.
I, JOHN MILLWARD, of Curzon Chambers, Paradise Street, Birming-
ham, in the County of Warwick, do hereby declare the nature of the
said Invention for "A NEW OR IMPROVED MACHINE FOR FORMING ELBOWS
OR BENDS IN SHEET METAL PIPES OR TUBES," to be as follows:-
This Invention consists in the construction of a new or improved
machine for manufacturing elbows or bends in sheet metal pipes or
tubes, such as those described in the Specification to Haseltine's Patent,
No. 3143, of 1870.

page_text: The essential feature and mode of operation involved in this machine
consist in passing the sheet metal pipe or tube by a step-by-step motion.
over a mandril, at the end of which are two sets of clamps or jaws,
surrounding the pipe and operating in such manner in combination with
a rocking disc or head, situated inside the pipe beyond the end of the
mandril, that as the pipe passes over the end of the mandril the one
set of clamps or jaws is caused to close down upon the pipe, nipping
it upon the end of the mandril, while the other set of clamps closes down.
and nips the pipe upon the rocking head, which in then being forcibly
brought together with the last-named clamps, and the portion of the
pipe nipped thereby close up to the end face of the mandril and the
first-named clamps, bends up or crimps a portion of the circumference
of the pipe situated between the two sets of clamps, and thus by a
succession of such crimpings or bendings at short distances apart the
elbow or bend is formed on the pipe.
Variously modified arrangements may be employed for actuating the
several before-mentioned principal parts of the machine, but by preference
the machine is constructed for this purpose in the following manner :-
The machine consists of a frame or stand, surmounted at a convenient
height by a horizontal barrel or hollow mandril, attached at the back
end to the machine frame and projecting at the front through a jaw-
shaped opening in the frame, in such a way that a cylindrically bent
sheet or plain pipe may be slipped over the same. At the free end the
mandril has a collar or circular head of about the same size as the inside
of the pipe, formed with a bead, extending round the greater part of its
circumference, and gradually decreasing in projection from the top to the
ends or points. A pair of half circular clamps or jaws operating
transversely to the mandril head are hinged to the frame on the under
side, and are fitted at their projecting upper ends with links and levers
by which they can be made to meet at the top and tightly clasp the pipe
on the said collar or mandril head, and the interior surfaces of the said
clamps have grooves to correspond with the bead on the collar before
described. The front of the mandril is fitted with a circular plate or head
of a similar size to the collar on the mandril, hinged on its under side
in such a manner as to permit of the pipe passing over it, and to be
capable of moving to and from the end of the mandril at the top, with
a vibratory motion upon its lower edge as a centre. A pair of clamps
similar to those before described and operating in the same manner, arc

page_text: hinged to the frame at their lower ends in such a way as to swing with
the last-mentioned head when tightly clasping the pipe over the same,
and the bead and the inside of clamps are so shaped as to prevent the
pipe slipping. The hinged head is operated by a rod attached to its
centre, which passes through the hollow mandril and is connected with
a cam or excentric on a short cam shaft mounted transversely at the
back of the machine. The end of the connecting rod may be so fitted
to the hinged head as to throw out a sliding tongue or plate on the
upper side of the head, at the moment when the closing action takes
place, as an additional device to prevent the slipping of the pipe. Upon
the outside of the mandril slides a concentric travelling head, having an
annular groove in its front to receive the end of the pipe to be bent,
and a wedge or screw for securing the pipe in the same. To this
travelling or sliding head a step-by-step forward motion towards the
aforesaid clamps is imparted by means of a bar secured to its under side,
which is in connection by a rack and spring pawl with a sliding block
behind the cam shaft before mentioned, and receiving from a separate
cam thereupon a feed motion forward, by steps corresponding with the
extent to which the hinged head in front of the mandril opens.
The operations of the machine as a whole is as follows:-'
The plain
pipe, either formed of a single cylindrically curved sheet, with a slight
overlap, or in any other known manner, is slipped over the fixed and
rocking head of the mandril into the annular groove in the sliding head
on the mandril, which is drawn back as far as necessary for the length
of the bend, and so as to leave the pipe projecting a little beyond the
heads. The inner clamps or those clasping collars on the mandril head
are forcibly closed, thereby partially crimping the pipe in a preparatory
manner over the bead on the said collar. These clamps are then released
and the cam shaft partially rotated by a suitable hand lever or other
means, thereby throwing open the hinged head and pushing forward the
feed block. Both pairs of clamps are now forcibly closed, the inner
ones forming another preparatory crimp, and the outer ones firmly
holding the pipe upon the rocking head. In this position the first
preparatory crimp lies in the space between the clamps; the outer clamps,
together with the rocking head are then drawn tightly against the inner
clamps and mandril collar by the hinge-like movement of the rocking
head, operated by a reverse rotation of the cam shaft, and the crimp in
the pipe is thus completed. By a repetition of this process the plain

page_text: pipe is converted by a series of preferably equidistant crescent-shaped
crimps into an elbow of any desired angle.
The manipulation of the clamps may be assisted by treadles, connected
by toothed sectors or other known means for opening and closing rapidly
and easily, independently of the links and knuckle levers for holding and
tightening the same, and the opening or releasing movement may be
assisted by springs. The cam movement for opening the hinged head
may also be assisted by a strong spring, suitably arranged so as to push
or pull the head away from the mandril.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John Millward in the Great Seal Patent Office
on the 30th August 1871.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
MILLWARD, of Curzon Chambers, Paradise Street, Birmingham, in the
County of Warwick, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Sixteenth day of March, in the year
of our Lord One thousand eight hundred and seventy-one, in the thirty-
fourth year of Her reign, did, for Herself, Her licirs and successors, give
and grant unto me, the said John Millward, Her special licence that I,
the said John Millward, my exccutors, administrators, and assigns, or
such others as I, the said John Millward, my executors, adminis-
trators, and assigns, should at any time agree with, and no others,
from time to time and at all times thereafter during the term therein
expressed, should and lawfully might make, use, exercise, and vend,
within the United Kingdom of Great Britain and Ireland, the Channel
Islands, and Isle of Man, an Invention for "A NEW OR IMPROVED MACHINE
FOR FORMING ELBOWS OR BENDS IN SHEET METAL PIPES OR TUBES," a com-
munication to me from abroad by Charles Hoeller, of Cincinnati,
Hamilton County, State of Ohio, United States of America, upon the
condition (amongst others) that I, the said John Millward, my executors
or administrators, by an instrument in writing under my, or their, or
one of their hands and seals, should particularly describe and ascertain
the nature of the said Invention, and in what manner the same was to be
performed, and cause the same to be filed in the Great Seal Patent Office

page_text: Wium Six calendar months next and immediately after the date of the
said Letters Patent.
NOW KNOW YE, that I, the said John Millward, do hereby declare
the nature of the said Invention, and in what manner the same is
to be performed, to be particularly described and ascertained in and by
the following statement thereof, reference being had to the accompanying
Sheet of Drawings, and to the figures and letters marked thereon, that
is to say :-
This Invention consists in the construction of a new or improved
machine for manufacturing elbows or bends in sheet metal pipes or
tubes, such as those described in the Specification to Haseltine's Patent,
No. 3143, of 1870.
The essential feature and mode of operation involved in this machine
consists in passing the sheet metal pipe or tube by a step-by-step motion
over a mandril, at the end of which are two sets of clamps or jaws
surrounding the pipe and operating in such manner in combination with
a rocking disc or head situated inside the pipe beyond the end of the
mandril, that as the pipe passes over the end of the mandril the one set
of clamps or jaws is caused to close down upon the pipe, nipping it upon
the end of the mandril, while the other set of clamps closes down and
nips the pipe upon the rocking head, which, in then being forcibly
brought together with the last-named clamps and the portion of the
pipe nipped thereby, close up to the end face of the mandril and the
first-named clamps, bends up or crimps a portion of the circumference of
the pipe situated between the two sets of clamps, and thus by a succes-
sion of such crimpings or bendings at short distances apart the elbow or
bend is formed on the pipe.
Variously modified arrangements may be employed for actuating the
several before-mentioned principal parts of the machine, but, by pre-
ference, the machine is constructed for this purpose in the following
manner: The machine consists of a frame or stand surmounted at a
convenient height by a horizontal barrel or hollow mandril attached at
the back end to the machine frame, and projecting at the front through
a jaw-shaped opening in the frame in such a way that a cylindrically
bent sheet or plain pipe may be slipped over the same. At the free end
the mandril has a collar or circular head of about the same size as the
inside of the pipe, formed with a bead, extending round the greater part
of its circumference, and gradually decreasing in projection from the top

page_text: to the ends or points. A pair of half-circular clamps or jaws operating
transversely to the mandril head are hinged to the frame on the under
side, and are fitted at their projecting upper ends with links and levers,
by which they can be made to meet at the top and tightly clasp the pipe
on the said collar or mandril head, and the interior surfaces of the said
clamps have grooves to correspond with the bead on the collar before
described. The front of the mandril is fitted with a circular plate or
head of a similar size to the collar on the mandril, hinged on its under
side in such a manner as to permit of the pipe passing over it, and to
be capable of moving to and from the end of the mandril at the top
with a vibratory motion upon its lower edge as a centre. A pair of
clamps similar to those before described and operating in the same
manner are hinged to the frame at their lower ends in such a way as to
swing with the last-mentioned head when tightly clasping the pipe over
the same, and the bead and the inside of clamps are so shaped as to
prevent the pipe slipping. The hinged head is operated by a rod attached
to its centre, which passes through the hollow mandril, and is connected
with a cam or excentric on a short cam shaft mounted transversely at
the back of the machine. The end of the connecting rod may be so
fitted to the hinged head as to throw out a sliding tongue or plate on
the upper side of the head, at the moment when the closing action
takes place, as an additional device to prevent the slipping of the pipe.
Upon the outside of the mandril slides a concentric travelling head
having an annular groove in its front to receive the end of the pipe to
be bent, and a wedge or screw for securing the pipe in the same.
this travelling or sliding head a step-by-step forward motion towards
the aforesaid clamps is imparted by means of a bar secured to its under
side, which is in connection by a rack and spring pawl with a sliding
block behind the cam shaft before mentioned, and receiving from a
separate cam thereupon a feed motion forward by steps corresponding
with the extent to which the hinged head in front of the mandril
opens
:
Το

page_text: heads. The inner clamps, or those clasping collar on the mandril head
are forcibly closed, thereby partially crimping the pipe in a preparatory
manner over the bead on the said collar. These clamps are then released,
and the cam shaft partially rotated by a suitable hand lever or other
means, thereby throwing open the hinged head and pushing forward the
feed block. Both pairs of clamps are now forcibly closed, the inner
ones forming another preparatory crimp, and the outer ones firmly
holding the pipe upon the rocking head. In this position the first pre-
paratory crimp lies in the space between the clamps. The outer clamps,
together with the rocking head, are then drawn tightly against the
inner clamps and mandril collar by the hinge-like movement of the
rocking head operated by a reverse rotation of the cam shaft, and the
crimp in the pipe is thus completed. By a repetition of this process the
plain pipe is converted by a series of, preferably, equidistant crescent-
shaped crimps into an elbow of any desired angle.
The manipulation of the clamps may be assisted by treadles connected
by toothed sectors or other known means for opening and closing rapidly
and easily, independently of the links and knuckle levers for holding
and tightening the same, and the opening or releasing movement may
be assisted by springs. The cam movement for opening the hinged
head may also be assisted by a strong spring suitably arranged so as to
push or pull the head away from the mandril.
But in order that this Invention may be fully understood I shall now
proceed more particularly to describe the manner of performing the
same, and for that purpose shall refer to the several Figures on the
accompanying Drawing, the same letters of reference indicating corre-
sponding parts throughout the corresponding Figures.
Figure 1 is a perspective view of a machine embodying this Invention;
Figure 2 is a longitudinal section, and Figure 3 an end elevation of the
same; Figure 4 is an enlarged view of the crimping heads; Figure 5 is
a detached view of the cam shaft for operating the feed and crimping
devices; Figure 6 is a side view of the hinge device for the crimping
clamps in connection with the rocking head.
A is the frame of the machine, and B is the projecting cylindrical
barrel for receiving the bent sheet to be formed into an elbow or bend.
The barrel or mandril B is secured to the frame by bolts C, D, or other
suitable attachment, and the unsupported end of it is constructed with a

page_text: collar or circular head E which has a bead e formed upon it which extends
with a gradually decreasing projection from the top to points near the
bottom. F, F, are clamps or jaws hinged to the frame in such a manner
that they close tightly upon the collar E to enclasp or nip the bent sheet
tube of which the bend or elbow is to be formed, and these clamps have
grooves corresponding with the bead e on the mandril head. G is the
rocking head hinged to the lower part of the collar E by means of the
bolt g or by other equivalent device. H, H', are clamps or jaws arranged
to close tightly upon the head G and having a groove / fitting over
the concave edge or bead of the said head. These clamps are designed
when closed to swing with the hinged head G, and are attached to a
stud frame I hinged to the frame A by a joint K (as shewn in Fig. 6)
in line with the bottom inner edge of the head G. The rocking head G
with its clamps when closed can be moved so as to close against the
inclined face of the collar E by means of the connecting rod L operated
by an excentric or cam m mounted on the transverse shaft M and by
the hand lever N in the manner shewn, or by devices equivalent thereto.
The head can be thrown open again by a reverse movement of the same
devices and connecting rod L assisted by the powerful spring O acting
upon the outer clamps. The clamps F, F¹, and H, H¹, are hinged to
open and close upon the bolts or pins P and are held firmly in the closed
position by means of links Q, Q', and cam-ended handles R, R'. The
bent sheet metal pipe from which the elbow is to be formed is pushed
over the heads E, G, when the clamps F, F, H, H³, are open and
the pipe is secured at the inner end in an annular groove in the sliding
head S by the cam lever T or other suitable device. The sliding block
or head S has secured to it the notched rod U for feeding the pipe
between the operations of crimping. This rod is operated by the spring
pawl V attached to the sliding block W by means of the cam X mounted
on the said cam shaft M. In order to provide an additional fastening
device for the portion of the sheet metal tube between the die G and its
clamps to prevent slipping the rod L is fitted with a tapering rectangular
head a which is fitted to force up a dovetail sliding tongue or plate Y
when the rod is pulled in the direction of cam shaft M: The tongue or
plate Y by this device secures the pipe inside in a very perfect manner.
For convenience of handling toothed treadles Z may be attached to the
machine for the purpose of closing up one side of the clamps. Also the
springs 6 may be affixed as shewn to assist in throwing out the same
part of the clamps.
b

page_text: It will be seen that the cams m and X are in line, and that when 'the
lever N is moved in the direction of the arrow the heads E, G, are
brought together to form the crimp in the elbow, and the pawl V moved
back at the same time for a new tooth in the feed rod U. In the
operation of moving the lever N in the opposite direction after the
necessary release of the clamps F, F¹, H, H', the head G is swung open
and the pipe fed or pushed forward the extent of one notch in the rod U:
It will be observed by reference to Figure 2, that before a pipe is
brought to a position between the heads E, G, for the crimp that it
has received, a slight preliminary crimp between the head Ee and
clamp F, F, f, which is designed for the very important purpose of
enabling the metal to bend properly in the formation of the final crimp
between the heads E, G. The operation of the machine is as follows:-
The sheet metal is first cut to length and rolled or bent to the form of
a cylinder and overlapped a little at the junction, or suitably fastened
together. This tube is then slipped over the heads E, G, into the annular
groove in the head S and secured there by the cam lever T. The tube
is then adjusted in such a position that it overhangs the heads E, G,
outwardly a short distance of two inches, more or less, in accordance
with the diameter of the pipe. The clamps F, F¹, are then closed tightly
and form in closing a preliminary curved crimp corresponding in shape
and length to the bead projection e. The lever N is then moved to the
extreme point in the direction of the arrow shown on the Drawing for
the pawl V to catch a new tooth, and then, after the clamps F, F¹, are
released it is reversed, and in this operation of reversing the pipe is moved
so that the preliminary crimp on the same is situated centrally between
the heads E, G. Both clamps F, F' and H, H', are then tightly closed
over the pipe, the clamps F, F, giving another curved preliminary
crimp as before, and the clamp G, by virtue of its concave shape or by
the help of the sliding tongue or plate Y operated by the tapering head a
to the connecting rod, grasping or nipping the metal firmly and thus
preventing slipping. The lever N is again moved in the direction of
the arrow, and a closed crescent-shaped crimp is formed between the
heads E, G, such as is shown outside of the head G in Fig. 2. This
operation is continued until by successive and preferably equidistant
crimps the pipe is turned to a right angle or other bend of any required
number of degrees.

page_text: By means of this Invention, elbows or bends for stove-pipes and many
other purposes of the kind herein-before described may be made more
rapidly, at less cost, and with greater accuracy and regularity than by
any other method at present known.
Having thus described the nature of the Invention and the manner
in which the same is to be performed, I wish it to be understood
that I do not limit myself to the precise details of construction and
arrangement herein-before described with reference to the accompanying
Drawing, as it is obvious that many modifications may be made in the
arrangement of the machine as a whole, and especially in the devices
for connecting and operating the clamps upon the heads E, G, and
also in the devices for operating the head G and feed block S, without
departing from the nature of the Invention, but what I claim as new
and desire to be secured to me by the herein-before in part recited
Letters Patent is :-
First. The construction of a machine for making pipe elbows or bends
wherein a barrel or mandril B, E, with clamps F, F", is arranged to
operate in combination with a hinged crimping device composed of a
rocking head G and clamps H, H³, substantially as and for the purposes
herein before described.
Second. The provision in connection with the mandril collar or head E
and clamps F, F, of the bead and groove e, f, or other equivalent device
for forming a preliminary crimp as and for the purpose herein-before
described.
Third. The combination and arrangement of parts for operating the
said rocking head and crimping device, consisting of the connecting
rod L, cam shaft M, m, and lever N, arranged substantially in the
manner shewn and for the purpose specified.
Fourth. The devices for feeding or pushing forward the pipe to be
formed into a bend by the operation of crimping, consisting of the
feed block S, feed rod U, pawl V, yoke or sliding block W, cam shaft
M, X, and lever N or other equivalent devices, combined and operating
substantially as and for the purposes specified.
Fifth. The sliding plate or tongue Y and tapered head a operating in
connection with the rocking head and connecting rod in the manner and
for the purpose specified.

page_text: Sixth. The retracting spring O acting in combination with the hinged
crimping device G, H, H' as and for the purpose described.
Seventh. The fastening device, for securing the clamps in their closed
position consisting of the links Q, Q, and the cam handle R, R', arranged
and operating substantially as herein-before set forth.
In witness whereof I, the said John Millward have hereunto set
my hand and seal this Twenty-sixth day of August, in the year
of our Lord, One thousand eight hundred and seventy-one.