An Improved Method of and Apparatus for Bending and Coiling Pipes.
Year: 1889

page_text: Date of Application, 30th July, 1889-Accepted, 23rd Nov., 1889
COMPLETE SPECIFICATION.
[Communicated from abroad by HERBERT ELLSWORTH FOWLER, of 119, Davenport
Avenue, New Haven, Connecticut, United States of America, Mechanic.]
An Improved Method of and Apparatus for Bending and Coiling
Pipes.
I, HENRY HARRIS LAKE, of the firm of Haseltine, Lake & Co., Patent Agents,
Southampton Buildings, in the County of Middlesex, 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 object of this invention is to bend thin or fragile pipe such as brass or copper,
without reducing it in size or crushing or indenting it. It is common in bending
such pipe to fill it with melted resin which is allowed to cool and before subjecting
the pipe to the bending operation, and after the pipe is bent it must be heated in
order to melt the resin for removal. It is not possible however by any method now
in use, to successfully bend thin brass or copper pipe without, to some extent,
reducing it in size and indenting its surface. The main difficulty has been in
feeding the pipe to the bending mechanism the feeding having been heretofore
accomplished by gripping the end of the pipe after it has passed between the bending rolls
and drawing it forward around the die or by clamping the bent portion of the pipe with
the die and drawing it forward as the die is rotated. These methods were faulty
in that the pipe could only be gripped throughout a small portion of its surface and
the force exerted operated to crush or indent it and also to draw it out or reduce it in
size.
By my improved method I am enabled to bend thin or fragile pipe into coils of
short diameter without filling the pipe and without injury to it or reducing it in
size.
The dominating feature of my invention is the method of feeding the pipe inter-
mittently to the bending mechanism by forcing it forward by means of appropriate
gripping devices applied to the straight portion of the pipe.
Features of the mechanical construction whereby 1 am enabled to feed pipe of soft
or thin metal and coil it, without injury, are gripping jaws which are of such
length as to distribute the strain upon the pipe to avoid crushing, said jaws being
caused to engage the pipe, preferably by toggle arms pivoted upon a sliding head
block operated by suitable gearing.
Another feature of my invention relates to an adjustable bending roll or die
whereby various sized coils may be formed without changing the dies and to novel
means for adjusting said roll or die. Other features will be hereinafter described and
particularly pointed out in the claims.
In the accompanying drawings
Figure 1 is a plan view of a machine embodying my improvements a fragmentary
portion of the driving pulley being broken away.
Figure 2 is a side elevation.
Figure 3 is a side elevation partly in vertical section, and
Figure 4 is a transverse vertical section on line 4, 4 of Figure 1, looking toward
the rear of the machine.
Referring to the drawings, 5 represents the table or bed of the machine which
may be of any convenient form and supported upon the pillar 6. 7 is a stud which
is stepped into the table 5 and bears upon its upper end a die or roll 8, having a
grooved periphery 8 within which the coiling is effected. 9 is a guide plate located
at one side of the path of the pipe as it passes to the die 8. 10 is a swinging plate
pivoted at its inner end upon the rotatable stud 7. The outer end of said plate has
its interior cut away to form guides for a movable block 11, into which is stepped,

page_text: so that it may rotate, a stud 12 which bears upon its upper end a grooved roll or
die 13, which rotates in the same horizontal plane as the grooved die 8, whereby to
effect the bending of the pipe between their opposing edges. 14 is a set screw
connected with sliding block 11 and adapted, by being turned, to reciprocate the
block 11 and thus to vary the distance between the dies 8 and 13, and thus determining
the diameter of the coil or bend. 15 is a curved ratchet plate secured at one end to
the swinging frame 10 and adapted to be moved in the manner hereafter described.
16, 16 are gripping jaws which are connected by screws 17, to the block 18, which
moves in ways 19 of the frame. The aperture of the jaws through which the screws 17
pass admits of a slight lateral movement of said jaws and the latter are made of such
length as to distribute the strain on the pipe sufficiently to prevent crushing or
indentation. The block 18 has a slot and pin connection as shown in Figures 1 and 3
with a short stud 20", projected from the front edge of a sliding block 20, which
moves also in the ways 19. A stud 21 projecting from the under face of the block 20
enters a cam groove 22ª of a cylinder 22 secured to rotate with a shaft 23 motion
being imparted to the latter by means of the worm gear 24 driven by the worin
shaft 25, the latter being rotated by power applied to the belt pulley 26 The block 20
carries on its upper face studs 27 upon which are pivoted short arms 28, the latter
being pivoted to the arms 29 which in turn are pivoted upon studs 30 projecting
from the face of the block 18. The forward ends of the armis 29 are adapted to
impinge upon the sides of the gripping jaws when the rear ends of said arms are
spread by the forward movement of the block 20. 31 is a bar secured to the block 18
and having on its end a dog or pawl 32 whose front end is adapted to engage the
teeth of the ratchet plate 15 above described, so that when the block 18 is moved
forward, the swinging plate 10 will he forced around in the direction of movement.
33 is a guide preferably in the form of the anti friction roller mounted in the block 34,
which is adapted to be moved in an aperture of the table 5 by means of a set screw 35
and to be vertically adjusted by means of a set screw 36 whereby said roller is
adapted to support the forming coil the first turn of which will rest thereon and to
direct the said coil above the die 8 as clearly shown in Figure 2. The lateral
adjustment of this guide adapts it to be used with coils of varying sizes and its
vertical adjustment adapts it to form coils of varying pitch it being obvious that
when the guide 33 is elevated more or less the turns of the coil will be more or
less open.
The operation of the machine is as follows.
A straight length of pipe has its forward end entered between the guide 9 and the
die being projected between the curved faces of the gripping jaws. Power applied
to the pulley 26, will operate through the worm gearing and cam wheel described to
impart a forward movement to the block 0, the initial effect of which will be to
spread the toggle arms at their ends and cause their forward ends to impinge upon
the gripping jaws 16. A further movement in the same direction causes the front
edge of the block 20 to impinge upon the rear edge of the block 18 and a forward
movement is imparted to the last named block thereby carrying forward the gripping
jaws and pipe and causing the latter to engage the die 13. If it be desired to bend a
coil of the exact diameter of die 8 the die 13 is suitably adjusted in the plate 10 and
the said plate is swung around into such a position that the die 13 will cause the
advancing pipe to follow closely the periphery of said die 8. If a coil of larger size
is required, the said plate must be moved through a smaller angle. Whenever the
plate 10 has been advanced by the action of the dog to such a position as will ensure
the production of a coil of the desired size the said dog is disengaged from the
ratchet 15. The plate 10 will be locked against a retrograde movement by the
engagement of a spring actuated pawl 10 with teeth 5" on the periphery of
the table 5. As the coiling progresses the pipe is guided by the roller 33 so as to
clear the die. It will be apparent that the pipe is coiled at each forward movement
of the jaws a distance equal to the movement of said jaws and the length of this
stroke may of course be varied at pleasure. At the close of the working stroke the
stud in the cam slot will have passed into the return part thereof, thereby effecting

page_text: the backward movement of the block 20 and the release of the gripping jaws. When
the pin of the stud 20 reaches the outer end of the slot in the block 18 during this
return movement said block will be caused to move backward carrying the jaws along
the pipe in position for a fresh attack.
It will be observed that in the operation of this machine as hereinbefore des ribed
the feeding of the pipe forward is effected by the impingement of the block 20 upon
the block 18 and the toggle arms will be of such length and so arranged and the
blocks 18 and 20 will be placed such a distance apart that the gripping effect will not
be increased during that part of the forward stroke in which the pipe is being coiled
so that the gripping will be uniform notwithstanding the fact that the power required
with different sizes of pipe or forms of bending mechanism may necessarily be varied.
In the construction as herein shown and described the bending mechanism consists
of circular rolls provided with grooved peripheries which rolls are rotatably mounted
their rotation being effected by the friction of the forwardly moving pipe but I do
not intend to limit my invention to any particular form of bending mechanism as it
is obvious that the stationary rolls of the form shown or stationary blocks with curved
and grooved faces, may be substituted therefor. The stationary devices would be
objectionable on account of the increased power necessary to force the pipe between
them but with some classes of work this objection would be merely trivial.
I do not intend to limit my invention to the particular method of reciprocating the
gripping jaws, although the gearing here shown has been found admirably adapted
for that purpose.
to
Having now particularly described and ascertained the nature of the said inven.
tion and in what manner the same is to be performed as communicated
me by my foreign correspondent 1 declare that what I claim is :-
First. The herein described improvement in the art of bending and coiling pipe
which consists in intermittently forcing or feeding forward a continuous length of
pipe through or between bending devices such as rolls or dies whereby the pipe is
formed into a series of convolutions.
Second. In a pipe bending and coiling machine, the combination, with suitable dies
for forming the coil or bend, of means for feeding the pipe to the dies, comprising
gripping-jaws adapted to engage the straight portion of the pipe and means for
causing said engagement and for reciprocating the jaws to force the pipe between the
bending dies, substantially as described.
Third. In a pipe bending or coiling machine, the combination, with suitable
bending dies, of means for forcing the pipe between said dies to form the coil, said
means comprising in combination gripping-jaws carried by a sliding block and toggle-
arms and suitable gearing for operating said arms to cause them to impinge upon the
gripping-jaws to secure its engagement with the pipe and means for reciprocating the
block to cause the jaws to advance the pipe, substantially as described.
Fourth. In a pipe-bending machine, the combination, with dies for bending or
coiling the pipe, of a pair of grooved gripping-jaws mounted upon a sliding block, a
second block adapted to be moved by suitable gearing into engagement with the first
and a system of toggle-levers pivotally connecting said blocks and adapted to bear
upon said gripping-jaws to cause their engagement with the pipe, substantially as
described.
Fifth. In a pipe-bending machine, the combination, with reciprocating clamping-
jaws for feeding forward the pipe, of a rotatable bending die, a second bending die
mounted upon a swinging plate and means, substantially as described, connecting
said plate with the feeding mechanism.
Sixth. In a pipe-bending machine, the combination, with reciprocating clamping-
jaws for feeding forward the pipe, of a rotatable bending die, a second bending die
mounted upon a swinging plate, means, substantially as described, connecting said
plate with the feeding mechanism and means for locking said plate to a stationary
part of the machine, substantially as described.

page_text: Seventh. In a pipe-bending machine, the combination, with the bending die, of a
guide over which the forming coil passes, said guide being vertically adjustable
whereby the pitch of the coils may be varied, substantially as described.
Eighth. In a pipe-bending machine, the combination, with the bending dies, of a
guide for the forming coils, said guide being vertically adjustable whereby the pitch
of the coils may be varied and laterally adjustable whereby it is adapted for use with
coils of varying diameters, substantially as described.
Dated this 10th day of July 1889.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, Agents for the Applicant.