An Improved Machine for Forming Solid Bars into Helices.
Year: 1891

page_text: Date of Application, 2nd Mar., 1891-Accepted, 4th Apr., 1891
COMPLETE SPECIFICATION.
CES.
An Improved Machine for Forming Solid Bars into Helices.
I, JOHN LAIDLAW, of the firm of Watson, Laidlaw & Company, of 98, Dundas
Street, Kingston, Glasgow, North Britain, Engineers, 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:
This invention relates to a machine for forming solid bars into helices.
In carrying out my invention I employ three or more, but preferably three
rollers. One of the rollers is carried on the end of a shaft. The upper or neck
bearing of this roller serves as an axis for a turn-table, arm, or their equivalents,
which carries one of the rollers at a determined distance from the revolving centre
of the turn-table. The third roller is carried on a short shaft running in a bearing
cast on the framework, and located immediately underneath the turn table.
There is a slot in the turn-table to allow this third roller to come into suitable
position, and at the same time permit of the turn-table being moved round as much
as is required.
It will be seen that since the axis of the first and the axis of the third roller
carried from, below the turn-table have fixed centres, the roller carried upon the
turn-table may readily be moved into any suitable position relative to the other two
rollers to obtain the required curve.
Suitable grooves are made in all the rollers to suit the section of the bar to be
operated upon.
A suitable roller or wedge-shaped surface is placed so that after the bar has passed
through the bending rollers it is forced over the guiding roller or wedge to give
the required, helix.
In order that my invention may be properly understood and readily carried into
effect I have hereunto appended three explanatory sheets of drawings, in the
several figures of which corresponding parts are marked with the same letters of
reference.
Figure 1 is an elevation partly in section.
Figure 2 is a plan.
Figure 3 is a transverse section on line a d.
The framework or stand of the machine is marked X.
A, B, and D are the three rollers. The roller A is carried on a shaft N, the
upper or neck bearing of which is in the centre of the turn-table C. The roller B
is supported on, and moves with, the turn-table, and is therefore always at a constant
distance from the central roller A. The third roller D is carried on an independent
shaft which comes up through the slot E formed in the turn-table. If the turn-
table is moved, the distance between the rollers D and B will be increased or
diminished, according to the direction of motion. A rack H is formed on the
periphery of the turn-table, so that the turn-table, with the roller it carries, may
be turned round by means of the hand-wheel F, and worm-wheel G. The position
of the roller B relatively to the rollers A and D can thus be adjusted to suit the
curve into which the bar is to be formed. The rollers are grooved as shown at
Figures 1 and 3 to suit the section of the bar to be operated upon. A guiding
surface C, Figures 1 and 2, is formed upon, or fixed to, the turn-table in
order to set the bar up into the helical form after it passes through the bending
rollers.
The arrangement for actuating the rollers will now be described.
The first motion-shaft carries a bevel-wheel J which gears with two bevel-
wheels K and K. By throwing the clutch L into gear with one or other of the
bevel-wheels K or K¹ the second motion-shaft M is caused to turn in either

page_text: direction. This second motion-shaft M communicates motion to the axis N of
the roller A by means of the worm O and worm-wheel P. The axis N
carries a tooth-wheel Q, gearing into a tooth-wheel R on the axis of the roller B.
The tooth-wheel Q also gears into an intermediate tooth-wheel S, which gears
into a tooth-wheel T, attached to the axis of the roller D.
It is necessary that all the rollers should be driven together by gearing, and
that the surfaces in contact with the bar operated upon should move in the same
direction as the bar when passing through.
To bend a bar V with this machine the table is turned to the proper position, so
that the bar passing from the roller D between the rollers A and B shall be bent
to the required curve. As the bar leaves the rollers it is forced slightly upwards
over the inclined surface C¹ so as to obtain the required helix.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is
.
The hereinbefore described machine for forming bars into helices, consisting of
two rollers whose axes are fixed relatively to one another, and a third roller carried
on, and moveable, with, a turn-table or its equivalent, the axis of one of the rollers
being in the centre of this turn-table, with an inclined wedge or guiding surface
attached to the turn-table; the three rollers being driven together by gearing,
substantially as described and illustrated on the accompanying drawings.
Dated this 28th day of February 1891.
BOTTOMLEY & LIDDLE,
154, St. Vincent Street, Glasgow, Applicant's Agents.