An Improved Machine for Cutting Spiral Mouldings.
Year: 1891

page_text: Date of Application, 10th Apr., 1891
Complete Specification Left, 9th Jan., 1892-Accepted, 13th Feb., 1892
PROVISIONAL SPECIFICATION.
An Improved Machine for Cutting Spiral Mouldings.
ALGERNON CHARLES PEMBERTON, 5 Dunster House Mincing Lane, London E.C.
Colonial Broker, do hereby declare the nature of this invention to be as follows:-
An improved method of cutting spiral mouldings in wood and other materials
for decorative and other uses.
This invention consists of a hollow mandril M the bore of which is sufficiently
large to allow the wooden blank on which' the spiral is to be cut to pass freely
through. At one end of the mandril, and for preference that nearest the revolving
cutter, is fixed a face plate F. with the centre bored out to the same size as the
hole in the mandril. This face plate has a rim sufficiently wide to revolve in a
bearing D and carries two lugs L. L. to which are hinged by means of the
brackets K. K. two rollers A A. These rollers are separately geared by two or
more cogs Z Z to two axles X X which pass through the centre of the pins Y Y
on which the brackets, K K are hinged. These axles X X have at the opposite
ends to Z Z, cogs cut with teeth to take the worm on the end of an axle T, which
passes through a hole in face plate F, which hole serves as a bearing for it, it then
proceeds in a parallel direction with the mandril for a few inches until it-terminates
in another bearing secured to the mandril M by a lug! (Not shewn in the drawings
for the sake of clearness.) This axle has a pinion wheel mounted on the opposite
end to that on which the worm is, so arranged that it shall engage with a fixed
circular rack C..
The action of the machine is as follows. When the mandril M is revolved a
convenient method of doing which is a worm as shown at G engaging in a cog E.
fixed ou the mandril. The pinion P revolves and turns the worm U fixed to the
same axle which in turn actuates the wheels N N from these the motion is con-
veyed to the hinged rollers A A through the gearing Z Z. The result being that
while the rollers A A revolve on their axles, the mandril M also revolves round,
and carries them with it, and the blank B which is being fed through M, is gripped
by the rollers AA. which are drawn together by the strong spiral spring Q, fixed
to the brackets K K and the blank is, propelled forward and revolved at the same
time so that a spiral motion is secured, the pitch of which entirely depends on the
relative rate at which the rollers A A are geared to move at in proportion to the
revolutions of the mandril M. Having secured the spiral motion of the blank, all
that is necessary to cut the spiral mouldings on it, is to fix a rapidly revolving
cutter at a proper angle to the work and arrange a guide to take the blank imme-
diately over where the cutter strikes it-to prevent chatter. These cutters are the
ordinary ones well known to all machine wood workers and there is no occasion
to enter into a description of them and they can be arranged to cut a groove of
any pattern desired round the blank by shaping the blades correspondingly.
In the drawings...
Fig. 1. is a side elevation of the machine.
Fig. 2.a view looking down from above...
Jis the stand on which the bearings are mounted. D. is a bearing to take the
nd of the mandril M, which is supported at the other end by the bearing D 2.
Sis a funnel to facilitate the entry of the blank into the mandril. O. O. are screws
o alter the tension at which the rollers A A grip the work..
.
To alter the machine from a, right handed spiral to a left handed one the motion
mparted to it is reversed (conveniently done by crossing the driving belt W.) and
n intermediate wheel introduced into the gearing either-between the rack C. aud

page_text: the pinion P. or between the cogs Z Z. The pitch of the spiral is conveniently
altered by making the axles carrying the rollers A A. square between the forks of
the brackets K K and so arranged that they can be readily withdrawn by removing a
pin and washer at the opposite side to the gear wheels Z Z when the rollers A A
can be changed for others of different diameter. In the drawing the machine is
arranged to cut a left handed thread, and only the feeding part of the mechanism
shown the cutters being placed as close to the rollers A A as the guide will allow.
April 10th 1891.
A. C PEMBERTON.
COMPLETE SPECIFICATION.
An Improved Machine for Cutting Spiral Mouldings.
I, ALGERNON CHARLES PEMBERTON, 5 Dunster House Mincing Lane
London E.C. Colonial Broker, 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 invention consists of a machine for cutting spiral mouldings of different
patterns round blank pieces of wood and other substances, for decorative and other
purposes.
It consists of a roller feed arrangement by which the blank is fed through a
guiding box with a regular spiral motion and while steadied by this guiding box.
the pattern is cut upon it by one or more rapidly revolving cutters. The following
is the construction of the machine, and its method of working.
M is a hollow mandril capable of revolving in the bearings B1 B2, the bore of
this mandril is sufficiently large to allow the blank J, on which the spiral is to be
cut, to pass freely through it. At one end of this mandril and for preference that
nearest the revolving cutters is fixed a face plate with the centre bored out to the
same size as the hole in the mandril. This face plate has a rim sufficiently wide to
take a bearing in the plummer block B1 and with the bearing B2 forms the bearings
on which the mandril revolves. On the face of this plate furthest away from the
mandril are fixed two lugs L L to which are hinged by means of the brackets K K,
two rollers RR. These rollers are separately geared by the train G G to the
axles XX which pass through the lugs LL (these axles have a steel bush over
each of them in which they can revolve, but the bush is secured in L by a set
screw, and the ends of this bush are allowed to protrude from L. on each side suffi-
cient to form a bearing for the brackets K K. to hinge on. These axles X X have
at the opposite ends to G, worm wheels W W both of which engage on opposite
sides of the screw S. The axle T carrying this screw passes back through the
face plate F which forms one bearing for it, and takes another bearing in the lug H
fixed to the mandril M close to this lug is fixed a pinion T 1 which engages on the
inside of the fixed internal wheel I.
The action of the machine is as follows,-When the mandril M.is revolved by
any convenient means (a worm-wheel and screw being shewn in the drawing D, D.S)
the pinion T1 revolves as it runs over the teeth of the fixed internal wheel I and
turns the screw S by means of the axle connecting them this in turn actuates the
worm wheels W W which convey their motion through the axles X. X and. from
thence through the gear wheels G G G to the rollers R R the result being that
while these rollers revolve on their own axles, they are also revolved in conjunction
with the mandril M and the blank which is being fed through M is gripped by the
rollers RR (which are drawn together by strong spiral springs O two being used one
on each side of the brackets K K) and as these rollers revolve in a direction which
drives the blank forward they are at the same time revolved with the mandril,fthe
result is that a regular spiral motion is secured to the blank the pitch of which
entirely depends on the relative rate at which the rollers are geared in proportion
to the revolutions of the mandril M...
. H_

page_text: Having secured the spiral feed of the blank, a block of wood or metal A is fixed
as close up to the rollers as possible.
This block for convenience is made in halves and bolted together, and has a
hole in it through which the blank can just pass without any shake, in the
top and bottom and also in the sides if desired are cut out semi-circular
openings wide enough to allow the cutters to operate on the blank. These cutters
are attached to ordinary cutter blocks on shafts and are of the general pattern well
known to machine wood workers. Two only are shown in the drawing one
engaging on the top of the blank, the other underneath fixed to the shaft C 2 hidden
from sight by the block A. If more than two cutters are required for an intricate
spiral the other cutters must be attached to vertical shafts arranged at a proper
angle to the work, this also applies to the horizontal cutter shafts, and may be
taken to be a right angle to the line of the pitch of the spiral. To facilitate the
adjustment of the shafts carrying the cutter blocks, so that the cutters shall lie in the
correct line of the pitch for various spirals, the holding down bolts of the plummer
blocks, in which the cutter shafts revolve, are made to slide in slots S L, in the
table supporting the machine; these slots permit of the ready moving of the shafts
for different pitches, and for changing the pitch from left to right, or the reverse.
To accomplish this the motion imparted to the mandril is reversed, conveniently
done by crossing the driving belt Z and moving the pinion T 1 to the axle V 1 by
which means motion given to the screw S is continued in the same direction as
when the mandril was revolved the reverse way, owing to the reversing action
of the two pinions V V which then come into play. Having reversed the feed of
the blank the cutter shafts are moved round about a quarter of a circle until C1
occupies the position previously held by C 2.
To alter the pitch of the spiral from fine to coarse, or the reverse, within certain
limits, the most convenient method is to make the axles carrying the rollers R R
square between the forks of the brackets K K, and so arranged they can be readily
withdrawn by removing a pin and washer at the end opposite the gear wheels GG,
other rollers of a different diameter can be substituted. Extreme changes can be
effected by making the studs, upon which the centre gear wheels G G revolve,
movable in the bracket K and substituting a different train of wheels.
In the drawings
Figure is a side elevation of the machine shown with the cutter shaft C1
broken off and its bearings removed to permit a clearer view of the block A.
Figure 2 is a vertical view looking down on to the machine.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what I
claim is,
The whole machine as heretofore described for cutting screws and spirals in wood
and other materials for decorative and other purposes.
Dated this Ninth day of January 1892.
A. G. PI
PEMBERTON.