IMPROVEMENTS IN MACHINERY OR APPARATUS FOR BENDING OR CURVING SOFT METAL TUBES
Year: 1872

page_text: LETTERS PATENT to William Robert Lake; of the Firm of Haseltine,
Lake, & Co., Patent Agents, Southampton Buildings, London, for
the Invention of "IMPROVEMENTS IN MACHINERY OR APPARATUS FOR
BENDING OR CURVING SOFT METAL TUBES."-A communication from
11
Canada
Sealed the 25th March 1873, and dated the 1st November 1872.
PROVISIONAL SPECIFICATION left by the said William Robert Lake
at the Office of the Commissioners of Patents, with his Petition, on
the 1st November 1872.
I, WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake, & Co.,
Patent Agents, Southampton Buildings, London, do hereby declare the
nature of the said Invention for "IMPROVEMENTS IN MACHINERY OR APPARATUS
FOR BENDING OR CURVING SOFT METAL TUBES," a communication, to be as
follows:-
This Invention has reference to improvements in machines or appli-
ances used for bending or curving soft metal tubes or pipes to form
curved pipes, elbows, syphons, and other like articles used in the
plumbing business, and for many other purposes. Such curved pipes or

page_text: other articles are commonly made of lead, and are worked out of sheet
lead by hand. Another manner of making them is by casting them in
moulds giving the required bend or curve; such castings are however
found to be very objectionable, as they are heavy and stiff to set should
any alteration be required to be given while fitting them to the place
they are intended to be used in; and another serious objection to these
castings is, that the metal is open and porous, often so much so that a
portion of the water passing through the pipe will pass through the body
of the metal and appear on the outside of the same. To produce a
machine capable of reducing the cost of making these pipes bent by
hand, and obviating with the objections above mentioned in cast ones, is
the object of the present Invention.
The bed of this improved machine is supported in any suitable manner,
and has two uprights forming bearings for, and carrying a shaft to
which is attached a fly wheel; it also carries a bevelled gear wheel
intermeshing with another bevelled gear wheel herein-after more par-
ticularly described. One end of the said shaft extends through the
bearings, and has a slot intó which a hardened steel die is fitted and
secured by pins or in any other suitable manner. The end of this die is
curved to the form of the pipe transversely, and includes about
90 degrees of the circle; its other end is similarly configurated to act
upon about one-half the circle, with the exception of being hollowed out
in the centre to about 80 degrees, so that while the first-named end acts
upon the upper surface of the pipe the other end acts more on the sides.
There is also a lower die upon which the pipe rests. There is a screwed
mandril which has a head at one extremity, while the other extremity is
pivotted to a block secured in a slot in the bed. The head is of the
proper diameter to fill the bore of the pipe to be bent.
I use a feed block bored out to fit and slide upon the top of the screw
of the mandril. In the front end of this block a serrated recess is formed
of the proper size to receive and hold the end of the pipe to be acted
upon, and a pin may be used or not as desired for holding the pipe.
At the back of the said block a nut fitted to the thread of the mandril
is placed. This nut is provided with an annular flange having ratchet
teeth upon its periphery. On the inner side of the flange on this neck a
a pawl block having an eye fitted to the neck is placed; this is provided
with a pawl. An arm extends from the pawl block to a slide working
on a shaft caused to run eccentrically throughout its length by means of

page_text: a bent end working in a centre bearing. Several centres may be pro-
vided at this point to adjust the eccentricity of the said shaft at one end.
The other end is provided with a curved arm, to which the second bevel
gear wheel is eccentrically attached and carried in a centre bearing. The
attachment is slotted to adjust the amount of eccentricity of this end of
the said shaft, and thereby vary the amount of feed caused by the action
of the pawl on the ratchet teeth. The said wheel is of such proportion
with regard to the first bevel wheel as to make two revolutions to one
made by the latter.
To prevent the turning of the feed block on the mandril it is pro-
vided with a pin entering a groove extending longitudinally in the
bed, and parallel with the axial line of the said mandril. A groove is
formed in the bed at such an angle that when the block travelling on the
mandril in a machine of this class constructed for bending 1½ inch pipes
has travelled seven inches, it will cause the said block to revolve on it to
the amount of about 30 degrees, and it will be well understood that the
proportion will vary with the size of the pipe. A pin for travelling in
this groove in this case is made flat, and set at an angle to suit that of
the groove.
A spring is attached at one end to the block, and is
connected to the bed. This spring is for the purpose of causing the block
to press against the nut, and prevent its turning when the pawl is drawn
back to make a fresh stroke for revolving the nut.
In constructing the bed die I divide the die into portions; one portion
is hollowed out so that the pipe when in place rests on two surfaces.
Round the whole of its surface it is bevelled, and in the said portions it
is slightly, by preference, rounded on its front side, and extremely so on
its back.
To prevent the catching of the pipe in the lower die when it is fed
forward by the block, or lifting bar of any suitable configuration is
pivotted at one end to the upright; to the other end is attached a link
or bar connecting it to an eccentric pin or an eccentric attached at
the end of the fly wheel shaft. Jam nuts are provided for adjusting
the lenght of the said link and the amount of lift required. The
working side of the ends of the upper die is rounded to the form of a
burnishing tool to prevent any cutting of the lead.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said William Robert Lake in the Great Seal Patent
Office on the 30th April 1873.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
ROBERT LAKE, of the Firm of Haseltine; Lake, & Co., Patent Agents,
Southampton Buildings, London, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the First day of November, in the year
of our Lord One thousand eight hundred and seventy-two, in the thirty-
sixth year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said William Robert Lake, Her special licence
that I, the said William Robert Lake, my executors, administrators,
and assigns, or such others as I, the said William Robert Lake, my
executors, administrators, 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 "IMPROVEMENTS IN
MACHINERY OR APPARATUS FOR BENDING OR CURVING SOFT METAL TUBES," a com-
munication to me from abroad by Robert Mitchell, of Montreal, Canada,
upon the condition (amongst others) that I, the said William Robert Lake,
my executors or administrators, by an instrument in writing under my,
or their, or one of their hands and scals, 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 within six calendar months next and immediately
after the date of the said Letters Patent.
NOW KNOW YE, that I, the said William Robert Lake, 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, reference being had to the accompanying
Drawings forming a part of this Specification.
This Invention has reference to improvements in machines or appli-
ances used for bending or curving soft metal tubes or pipes to form
curved pipes, elbows, syphons, and other like articles used in the

page_text: plumbing business, and for many other purposes. Such curved pipes or
other articles are commonly made of lead, and are worked out of sheet
lead by hand. Another manner of making them is by casting them in
moulds giving the required bend or curve; such castings are however
found to be very objectionable, as they are heavy and stiff to set should
any alteration be required to be given while fitting them to the place
the are intended to be used in; and another serious objection to these
castings is that the metal is open and porous, often so much so that a
portion of the water passing through the pipe will pass through the body
of the metal and appear on the outside of the same. To produce a
machine capable of reducing the cost of making these pipes bent by
hand, and obviating the objections above mentioned in cast ones is the
object of the present Invention.
The said machines, although more particularly designed for the manu-
facture of lead tubes, may also be used for making tubes of other ductile
metals and compositions of metals; and for some of these it will be
necessary to increase the strength of some of the parts of the machine.
Figure 1 is a plan of the said improved pipe bending machine; F
is a side elevation; and Figure 3, an end elevation of the same.
Figures 4, 5, and 6 shew details of the said machine.
Figure 7 shews a section of blank No. 1.
Figure 8 shews the product of Figure 7.
Figure 9 shews a section of blank No. 2.
Figure 10 shews the product of Figure 9.
Figure 11 shews à section of blank No. 3.
Figure 12 shews the product of Figure No. 11.
Figure 13 shews the details of the lower die.
Figure 14 shews a cross section of the pipe.
A is the bed of this improved machine, which is supported i
suitable manner. B, B, are two uprights forming bearings for the sh
o which is attached a fly wheel D. On that part of it betwe
bearings B, B, is secured a bevelled gear wheel E, intermeshing

page_text: another bevilled gear wheel F, herein-after more particularly described.
The end G of the spindle shaft. C extends through the bearings B, as
shown. In this end a slot is formed into which a hardened steel die is
fitted and secured by pins passing in through the two parts or in any
other suitable manner. This die is of the configuration more clearly
shown in Figure 3, the end H being curved to the form of the pipe
transversely, and including about 90 degrees of the circle. Its other
end H¹ is similarly configurated to act upon about one half the circle,
with the exception of being hollowed out in the centre to about
80 degrees; so that while the end H acts upon the upper surface of the
pipe, the other end H' acts more on the sides. I is the lower die upon
which the pipe rests. K is the head of the screwed mandril L, the other
extremity of which is pivotted by a pin M to a block N attached in a
slot in the bed A. This provides for the necessary amount of adjustment
of the head K, where its extremity terminates over the die I. The
head K is of the proper diameter to fill the bore of the pipe to be
bent.
O.is the feed block bored out to fit and slide upon the top of the screw
of the mandril L. In the front end of this block a serrated recess P is
formed, as more clearly shown in Figures 5 and 6, all of the proper size
to receive and hold the end of the pipe to be acted upon. Q is a pin
which may be used or not as desired for holding the pipe in position.
At the back of the block O a nut R fitted to the thread of the
mandril L is placed. This nut is, provided with an annular flange,
having ratchet teetli S upon its periphery. On the inner side of the
flange on this neck a pawl block T having an eye fitted to the neck is
placed. This block is provided with a pawl U, constructed and arranged
in the ordinary manner. V is an arm extending from this pawl block
to a slide W, working on the shaft X. This shaft is caused to run
eccentrically throughout its length by means of a bent end y working
in a centre bearing Z, and several centres may be provided at this point
to adjust the eccentricity of this end of the shaft X. The other end
is provided with a curved arm a, to which the wheel F is eccentrically
attached, and is carried in a centre bearing b. The attachment is slotted
to adjust the amount of eccentricity of this end of the said shaft X, and
thereby vary the amount of feed caused by the action of the pawl U on
the ratchet teeth S. The wheel F is of such proportion with regard to
the wheel E as to make two revolutions to one made by the latter.

page_text: To prevent the turning of the feed block O on the mandril L it is
provided with a pin c entering a groove d, extending longitudinally in
the bed and parallel with the axis line of the mandril L.
e is a groove
which may be of greater depth cut at such an angle that when the
block O travelling on the mandril L in a machine of this class con-
structed for bending one and a half inch pipes has travelled seven inches
it will cause the block O to revolve on it to the extent of about thirty
degrees. It will be understood that the proportion will vary with the
size of the pipe. c¹ is the pin for travelling in the groove e. In this
case it is made flat, and is set at an angle to suit that of the groove,
and must have considerable width in the direction of the groove. The
pin c will also be of similar construction, only that it will be straight,
and its width will be in the direction of the groove d. f is an elastic
cord or spring attached at one end to the block O.
roller and returns and is connected to the bed A, as
in Figure 1. This is for the purpose of causing the block O to press
against the nut R, and by the friction created to prevent its turning,
when the pawl U is drawn back to make a fresh stroke for revolving the
nut.
g
It passes over a
clearly delineated
In constructing the bed die I the following particulars will be observed,
as shown in Figure 13. K is the head of the mandril and K' the pipe
being bent, while I is the lower die in its relative position during the
process; 1, 2, 3, 4, divide the die into positions, that part of it between
2 and 3 is hollowed out, so that the pipe when in place rests on the two
surfaces 1 to 2 and 3 to 4. Around the whole of its surface it is bevelled,
and in the portions between 1 to 2 and 3 to 4 it is slightly by preferenco
rounded on its front side and extremely so on its back. These roundings
off on the back commence at the points 2 and 3, and increase as they
approach respectively the points 1 and 4.
To prevent the pipe when being fed forward by the block O being
caught in the lower die a lifting bar h of any suitable configuration is
pivotted at one end to the upright B, to which at the other end is
attached a link or bar i, connecting it to an eccentrically situated pin,
or an eccentric attached to the end of the shaft C. By this contrivance
the mandril head K with the pipe upon it is lifted free from the bed die I,
preventing the catching of the pipe therein and its being injured. ',,
are jam nuts adjusting the length of the link i and the amount of lift
required.

page_text: It will be also observed in constructing the ends H and H' of the
upper die that the working side is rounded to the form of a burnishing
tool to prevent any cutting of the lead, as by its action the end is spun
or pressed out.
It may be well here to explain the peculiarities required in the pipes
to be bent. To produce the elbow shewn in Figure 8 I cast the straight
blank shewn in Figure 7, having a swell 7 formed upon it. The swell /
contains a superabundant amount of metal sufficient to form the extended
length of the outer side of the elbow in Figure 8. In placing the said
blank on the mandril this swell is placed concentrically under the centre
of H and H. The blank shewn in Figure 9 is provided with two
swells m and n, the swell n being first worked out to form the short bend
in Figure 10. The pipe is then turned about and placed in the opposite
direction on the mandril for the swell m to be above and acted upon.by
Hand H, giving the form shewn in Figure 10. The amount of the
bend is regulated by the superabundant amount of metal contained in
the swells.
When it is desired to form a bend similar to that shewn in Figure 12
I cast a blank having a swell q as shewn in Figure 11. In this case
however the swell instead of being straight with the axis of the bore of
the pipe, as in the foregoing cases, is laid on with a left hand turn of
thirty degrees of the circumference of the pipe to seven and a half inches
of its length or thereabouts; that is as before mentioned for one and a
half inch pipe, and more or less according to the size of the pipe.
In forming the above described swells on the blanks Figures 7, 9, and
11, the cross section of the pipe will be as shewn in Figure 14, consisting
of two circles eccentric to each other, the amount of eccentricity being
governed by the amount of metal required.
Pipes of equal thickness all around their circumference may also be
bent by this machine, but the product will be an inferior article as the a
outer curve of the bend will be considerably thinner than the inner
one.
Having thus fully described the said Invention as communicated to
me by my foreign correspondent, and the manner of performing the
same, I wish it understood that I claim,-
First. The combination with the die I and the mandril L of the
working die H, H', substantially as and for the purposes set forth.

page_text: Second. The combination of the threaded mandril L and the shaft X
of the intermediate mechanism, through which feed motion is imparted
to the pipe, substantially as described.
Third. The lifter mechanism, consisting of the bar h, connecting rod i,
and eccentric pin in combination with the die I, substantially as and for
the purposes set forth.
In witness whereof, I, the said William Robert Lake, have here-
unto set my hand and seal, this 30th day of April, in the year
of our Lord One thousand eight hundred and seventy-three.
Witness,
HY. J. NOONE.
WM. ROBT. LAKE. (L.S.)