Improvements in and relating to Apparatus for Bending and Coiling Metal Pipes, Bars, Rods, Plates, and the like.
Year: 1891

page_text: Date of Application, 13th June, 1891
Complete Specification Left, 14th Mar.. 1892-Accepted, 16th Apr., 1892
PROVISIONAL SPECIFICATION.
Improvements in and relating to Apparatus for Bending and Coiling
Metal Pipes, Bars, Rods, Plates, and the like.
I, HUBERT HENRY GRENFELL, of 7 Great Saint Helens, in the City of London,
Captain Royal Navy, do hereby declare the nature of this invention to be as
follows:-
My invention relates to machines or apparatus for bending and coiling metal
pipes, bars, rods, plates and the like. My said invention relates more especially to
the kind or class of machines described in the Specifications of Letters Patent,
No. 12,115 of A.D. 1889 and No. 15,104 of A.D. 1889.
In the said machines the arrangements are such that it is possible only to bend
the pipe or bar or the like towards one side of the line in which it is fed into the
machine. According to one part of my present invention I so arrange that it is
possible to bend the pipe or bar or the like towards either side of the line in which
it is fed into the machine.
For this purpose I so modify the bed of the machine that the bending rolls may
be adjusted to a position on either side of the line in which the pipe or bar is feil
into the machine. The coil or bend will thus be formed right-handed or left-
handed as desired. I further arrange that the swing table which supports the
article after being bent may swing at either side of the line of delivery in accord-
ance with the adjustment of the bending rolls. Moreover I modify the front die
slide so as to make it also adjustable to either side. The swing table bed is
extended to correspond with the increased range of the swing table.
The swing table bracket is pivoted to the centre of the bed instead of at one
side thereof so that it can swing from one side to the other of the machine when
the direction of the bending of the pipe or bar is altered.
According to another part of my invention I propose to provide the gripping
feed jaws with removable liners to suit the various sizes of pipes dealt with and
thus ensure a more effective grip and feeding action.
My said invention also comprises improved means for forcing the pipe, bar or the
like towards the feeding and bending rolls.
It has been found that in bending large pipes or rails for which great force is
required, friction or gripping jaws are liable to slip. To prevent this I provide a
cross piece at or near the rear end of the pipe and so arrange that the cross-piece is
pulled forward to the rolls, either by chains passed over chain pulleys or by bars.
When operated by chains the said chains are either attached to the reciprocating
table described in the aforesaid Specifications or the said table is dispensed with
and the chain pulleys are geared with the rolls so that the pipe is fed continuously
forward. When operated by bars one end of each of the bars is secured to the
reciprocating table above referred to and the opposite ends of the bars pass through
the cross piece. Ratchet teeth are formed on the bars with which pawls carried
by the cross piece engage. With this arrangement the feed is intermittent, for
when the bars are carried forward by the reciprocating table they pull with them
the pipe or article being bent and when the table moves back the pawls become
disengaged and slide to the rear until the table again moves forward, whereupon
the pawls again engage with the teeth and the tube or other article is fed further
forward.

page_text: COMPLETE SPECIFICATION.
Improvements in and relating to Apparatus for Bending and Coiling
Metal Pipes, Bars, Rods, Plates, and the like.
I, HUBERT HENRY GRENFELL, of 7 Great Saint Helens, in the City of
London, Captain Royal Navy, 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 :-
My invention relates to machines or apparatus for bending and coiling metal
pipes or tubes, bars, rods, plates and the like and more especially to the kind or
class of machines described in the Specification of Letters Patent No. 12,115 of
A.D. 1889, and No. 15,104 of A.D. 1889.
In the machines described in the said Specifications the arrangements are such
that it is possible only to bend the pipe or bar or other article to one side of the
line in which it is fed into the machine. According to one part of my present
invention I so construct the machine that it is possible to bend the pipe or bar or
the like to either side of the line in which it is fed into the same, and, according to
another part of my invention I provide improved means for forcing the pipe, bar,
or the like towards the bending rolls, the said improved means being designed to
obviate the employment of friction or gripping jaws, which are liable to slip. My
said invention comprises also certain improvements in details of the apparatus,
which are hereinafter more particularly referred to.
In order that my said invention may be clearly understood I will now proceed to
describe the same with reference to the accompanying drawings, in which
Figure 1 is a plan of one end of a bending machine of the kind hereinbefore
referred to, with a pipe or tube between the bending rollers, bent to one side of the
line of feed.
Figure 2 is a plan similar to Figure 1, but with parts of the apparatus in the
position necessary for bending the pipe in the opposite direction to that in which
the pipe in Figure 1 is bent.
Figure 3 is a side elevation of Figure 2.
Figure 4 is an end elevation of a die and die-slide shown in plan in
Figure 2, and
Figures 5, 6 and 7 are plans of pipe-bending machines in which I have shown
novel mechanism for forcing the pipe or tube towards the bending rolls.
Like letters of reference indicate corresponding parts throughout the drawings.
With reference first to Figures 1, 2, 3,. and 4, A is the main frame of the
machine. B is a bed arranged to travel upon a suitable transverse guide formed
upon the main frame A. The said bed differs from those described in the said
former Specifications inasmuch as it is made semicircular in plan, for reasons which
will hereinafter be explained. C is a screw which may be operated from either
side of the main frame to move the bed B upon the said guide transversely to the
line in which the pipe is fed into the machine.
D is a swing bracket pivoted at D¹ to the centre of the bed B so that it can
turn horizontally about its pivot through an angle of 180° upon the semicircular
bed B. D is a sliding block movable in guides formed in the swing bracket and
D³ is a screw carried in the outer end of the said bracket and adapted to bear upon
the block D2 to force it against the edge of the bed B in order to retain the swing
bracket in any position to which it may be adjusted about its pivot, and the said
screw may be screwed back to relieve the said block from pressure when it is
desired to re-adjust the said bracket. The said bed is made semi-circular in order
that the swing bracket may be conveniently secured thereto at any angle within its
range of 180° by means of the block D' and screw D³ as aforesaid. Upon the said
pivot and above the swing bracket D is a swing slide E. F F are the grooved
bending rolls one of which is pivoted upon the pin about which the swing bracket D

page_text: turns, the other being carried upon the said bracket. The said rolls are both in
the same horizontal plane and lie between the swing bracket D and the swing
slide E. The spindle F of the bending roll carried upon the swing bracket is
supported at its lower end in a block, not visible in the drawings, which block is
adapted to slide in the aforesaid guides formed in the swing bracket D, and the
upper end of the said spindle is received by a block F which is adjustable in the
slide E by a screw E' carried in the outer end of the said slide.
By the employment of the semi-circular bed B the swing bracket D may be
adjusted to either side of the line of feed, as shown in Figures 1 and 2. By means
of the screw E, the bending roll on the said bracket may be readjusted relatively
to the roll carried by the pivot D¹ in order to vary the distance between their
peripheries. By reason of the engagement of the lower end of the spindle F' with
the block in the guides of the bracket D the slide E when the said swing bracket
is turned upon its pivot, will always maintain the position relatively to the swing
bracket in which it is shown in the drawings, that is to say, will always be vertically
above and parallel to the said swing bracket.
G is a part adapted to slide in the groove of the main frame of the machine, and
to be secured at any suitable point therein by bolts or otherwise. This part G is
provided with jaws G in each of which are vertical recesses G. H is the front
die slide or support for the pipe near the point at which it enters the space between
the rolls. The said die is provided upon one face with a semicircular recess to
receive the pipe and upon its opposite face with vertical projections or ribs adapted
to fit the recesses G2 in the part G. Both sides of this part G are provided with
recesses so that the said front die may according to this invention be placed therein
on either side of the pipe, and, when the said die is so placed, with its ribs engaging
with the recesses G³ it is secure against endwise displacement and acts upon the
portion of the pipe passing towards the rolls to keep that portion of the pipe in the
line in which it is fed into the machine. The said die projects forward from
the part G sufficiently to afford a support to the pipe at a point near that at which
the bending is commenced.
Upon the underside of the bed B are two hollow bosses B', fitted with a screwed
spindle B having a handle B'. I is the table upon which the pipe is received after
being bent. Upon its under side this table is provided with a stud adapted to enter
the upper end of the aforesaid hollow bosses, and, according to the direction in
which the pipe is to be bent the said table is adjusted so that its stud will enter one
or other of the hollow bosses B' to retain the table in position at either side of the
line in which the pipe is fed into the machine as shown in Figures 1 and 2. The
end of the screwed spindle B³ bears on the end of the stud and can be screwed into
or out of the hollow boss so that by raising or lowering the said stud it will raise or
lower the table 1. By raising the table above the plane in which the pipe is fed
into the machine the said pipe may be bent upward as it issues from between the
rolls, and spiral coils may in this way be formed.
With reference now to Figure, J is a cross-piece provided with a recess J¹ to
receive the rear end of the pipe which is to be bent. K K are endless chains
which are secured to the cross piece J, and are wound around a barrel L secured
upon a driving shaft L', and passed over sheaves M supported upon shafts which
turn in suitable bearings in the main frame A.
In Figure 6, N is a reciprocating table which may be substantially similar in
construction to that described in the said prior Specifications, but which differs
therefrom in being provided with rearwardly extended ratchet bars N¹.
O is a cross-head, so arranged that the rear end of the pipe which has to be bent
will abut against the same. The said cross-head is provided with pawls O' and
means whereby the said pawls are constantly maintained in contact with the ratchet
bars N¹.
In Figure 7, P P are the gripping jaws of a reciprocating table N. The said
jaws are provided with a tubular liner Q which is adapted to receive the pipe to bę
bent, and to prevent it from being deformed by the pressure of the gripping jaws

page_text: The said tubular liner is provided with several series of holes Q1, into any pair of
which a pin R is inserted to bear against the rear end of the pipe which is being
bent, in order that when the table N and gripping jaws move forward, carrying the
tubular liner with them, the pipe may be fed to the bending rolls by the action of
the pin R on its rear end.
The operation of bending a tube by means of my improved apparatus is similar
to that described in the hereinbefore mentioned former Specifications, but as herein-
before stated, by means of the improvements herein described a pipe or tube or
other article when properly placed in the machine may be bent towards either side
of the line in which it is fed to the bending rolls.
The rotation of the shaft L Figure 5 by any suitable means, such as by gearing
connecting the same with the bending rolls, with the reciprocating table described
in the said former Specifications, or with other moving portion of a tube-bending
machine, will cause the chains K to pull the block or cross-piece J towards the
bending rolls, so as to exert pressure upon the end of the pipe to feed it forward.
The return movement of the table can be effected by reversing the direction of
movement of the chain K or by disengaging the cross piece J from the chain and
moving it to the rear by any suitable means.
In the arrangement illustrated in Figure 6 the feed is intermittent, for, when the
bars N are carried forward by the table, the ratchet teeth on the said bars engage
with the pawls O' upon the cross piece O which is thereby forced forward. When
the table moves back the pawls slide to the rear over the ratchet teeth, until the
table again moves forward whereupon the pawls again engage with the ratchet teeth
upon the bars and the tube or other article is fed further forward.
In the arrangement illustrated in Figure 7 the feed is also intermittent, the
table N in moving forward, carries the tubular liner Q with it and the pin Q¹
moving with the tubular liner, acts upon the rear end of the pipe or tube contained
in the liner and feeds it forward therewith. When the table has completed its
forward movement the pin Q' is withdrawn from the liner the table is moved back,
and the pin is replaced in the liner at such other point as will cause it to be close
behind the end of the tube, and the table is again moved forward as before. When
the range of adjustment of the pin in the tubular liner becomes insufficient to enable
the pin to be put further forward therein the liner may itself be re-adjusted in the
table and a fresh series of feed operations commenced.
If gripping jaws such as those described in the said former Specifications are
used I prefer to provide them with removable liners properly formed to effectually
grip the pipe or other article.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed 1 declare that what I
claim is :-
:-
1. A machine provided with apparatus such as that herein described for bending
a metal pipe or tube or other article in either direction transversely to the line of
feed.
2. The combination of the bending rolls or equivalent devices with the bed and
the pivoted bracket, substantially as and for the purpose specified.
3. The formation of the bed with a semi-circular edge or rim for the purposes
specified.
4. The combination substantially as set forth, with the said bending devices, bed,
and bracket, of the table and means for securing the same on either side of the line
of feed for the purpose specified.
5. The combination with the said table of means, such as are herein described,
for raising and lowering it relatively to the bed and slide for the purpose
specified.
6. The combination with the bending devices, the transversely moving bed, and
pivoted bracket, of suitable feed mechanism substantially as and for the purpose
specified.

page_text: 7. The improved feed mechanism constructed substantially according to either of
the forms or modifications described with reference to Figures 5, 6, and 7 of the
drawings for the purpose specified.
8. An improved bending machine consisting of parts substantially such as are
described with reference to the accompanying drawings and operating as set forth
for the purposes specified.
Dated this 14th day of March 1892.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, Agents for the Applicant.