IMPROVEMENTS IN THE MANU- FACTURE OF COMBS, AND IN THE MACHINERY OR APPARATUS EMPLOYED THEREIN.
Year: 1878

page_text: LETTERS PATENT to John Lumsden Nelson, of the City and County of
Aberdeen, North Britain, for the Invention of "IMPROVEMENTS IN THE MANU-
FACTURE OF COMBS, AND IN THE MACHINERY OR APPARATUS EMPLOYED
THEREIN.
"
•
PROVISIONAL SPECIFICATION left by the said John Lumsden Nelson at the
Office of the Commissioners of Patents on the 3rd October 1878.
JOHN LUMSDEN NELSON, of the City and County of Aberdeen, North Britain.
"IMPROVEMENTS IN THE MANUFACTURE OF COMBS, AND IN THE MACHINERY OR
APPARATUS EMPLOYED THEREIN."
This Invention has for its object to cut combs with greater speed and regularity,
and of any shape required at the same time, with more ease to the operative than
is effected by the machines at present in use.
The foregoing object is effected by a machine having the guides for its circular
saw on a movable quadrant, which can be screwed up tight on to the same centres
as those on which the saw itself revolves, thus securing simultaneous action on the
part of the saw and its guides, and thereby great accuracy of cutting.
In order to regulate the number of teeth in the comb I employ a catch with a
double lift to enable the machine to cut any pitch of tooth required in a comb.
.
"
In order to cut teeth in a comb of any shape whatever I use a roller, the same
shape as the back of the comb to be cut, attached to the back part of the "glands
or comb holder, and moved simultaneously with the "glands" by the tumbler on
the main shaft of the machine.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said John Lumsden Nelson in the Great Seal Patent Office on the 2nd
April 1879.
JOHN LUMSDEN NELSON, of the City and County of Aberdeen, North Britain.
"IMPROVEMENTS IN THE MANUFACTURE OF COMBS, AND IN THE MACHINERY OR
APPARATUS EMPLOYED THEREIN."
My said Invention has for its object to cut combs of any shape required with
greater speed and regularity, and with more ease to the operator than is effected
by the machinery at present in use..
The foregoing object is effected by a machine having the guides for its circular
saw on a moveable quadrant, which can be screwed up tight on to the same centres
as those on which the saw itself revolves, thus securing simultaneous action on the
part of the saw and its guides, and thereby greater accuracy of cutting. In order
to regulate the number of teeth in the comb I employ a catch with a double lift to
enable the machine to cut any pitch of tooth required in a comb.
In order to cut teeth on a comb of any shape whatever I use a roller the same
shape as the back of the comb to be cut attached to the back part of the "glands"
or comb holder, and moved simultaneously with the "glands" by the tumbler on
the main shaft of the machine.
And in order that my said Invention may be properly understood, I now proceed
more particularly to set forth the system, mode, or manner in or under which the
same is or may be used or practically carried into effect, reference being had to the
accompanying Drawings, and to the letters and figures marked thereon, that is to
say:
Figure 1 represents in side elevation a machine constructed according to my
Invention. The circular saw A is mounted in standards A' capable of being
adjusted forward or backward by means of the screw A³. The guides B for the
said saw are connected to a casting C by the pin at b, upon which the said guides
can be turned so as to be adjustable in their position, their motion for adjustment
being allowed by the quadrantal slot c, and they being fixed in such adjusted
position by screwing up the pinch nut c¹. The guides and connections are shewn
separately in elevation in Figure 2, and in plan in Figure 3. They have adjustable
spring knobs b¹ to bear upon the face of the saw. In the bearings c² (connected by
the web c³) forming part of the casting C is secured by the set screw a², the spindle a
having a pivot end a¹ for one side of the saw, the spindle for the other side of the
saw being of the usual construction and furnished with a pulley A³ for driving the
saw from an overhead shaft or otherwise. The part of the spindle a between the
bearings c² is the part which is mounted in the standard A' on the one side of the
saw. The comb holder (or “glands") D (represented separately in back elevation
in Figure 4) turns upon centres at d, its weight at back preponderating, so that it
inclines to fall back. It has at top jaws ď¹, the upper one of which can be urged
down by the screw d² to grip tightly the comb x placed between them. At the
back of the comb holder D is a shaper E so held between pivots e, e, that it is
free to rotate, and may be readily removed and replaced by a straight piece for
straight combs, or by "shapers" corresponding to the shape of the back of the
comb being cut. The comb is alternately fed up to the saw and allowed to fall
back therefrom by a cam fupon a cam shaft F which is driven through the toothed
wheel upon it by a pinion f' upon a shaft driven from the same shaft which
drives the saw, or from other convenient shaft, the speed being suitably reduced.
The comb holder D is mounted upon a foundation piece D¹ sliding upon the bed
plate of the machine, it having a lug through which a screw passes, the said screw
having on its end the ratchet wheel G, and being provided with a handle g for
rotating the screw by hand when required.

page_text: Upon the shaft F is a cam h which acts upon a lever H turning upon a stud at
h. This lever H is connected by the rod I to a lever or catch J turning upon a
stud j adjustable in a bracket K, the holes in the said lever and in the bracket
being slotted as shewn. k are checks to limit the stroke of the levers H and J, and
prevent their taking too much of the wheel, or to be used as a finer index or
adjustment if required.
When the machine is in operation the rotation of the shaft F causes the cam f to
bear upon the "shaper" E and urge up the comb holder D, and cause the saw to
make its cut to a depth according to the part of the "shaper " E upon which the
cam bears, the said comb in its progress depressing the guides B. When the cut
has been made to its proper depth the cam fallows the comb holder D to fall back
and the comb is withdrawn from the saw, the guides B following the comb till the
web of the casting C comes into contact with a stop c which is adjustable in the
standard A'. As the saw is making its cut the lever H is without motion, but
when the comb is clear of the saw the lever H being acted upon by the cam /
causes the lever or catch J to draw back the ratchet wheel G fixed upon the screw,
upon which the comb holder traverses as aforesaid, giving motion of rotation to the
said screw and feeding forward the comb into position for the next cut. As soon
as the cam h allows the arm H to come forward the lever or catch J rides over the
ratchet wheel G. These operations are repeated till the cutting is completed, the
inner ends of the guides B being depressed by the comb as each cut is made, and
returning upward by the weight of their other end as the comb is withdrawn from
the saw, and in their said motions always turning upon the same centre as that
upon which the saw turns. The adjustment of the stud j in the slot in the
bracket K gives a variable degree of stroke to the lever J, so that the ratchet
wheel G may be brought over to a greater or less extent according to the adjust-
ment, and therefore a greater or less travel be given to the comb holder D at each
stroke. The "shaper" E causes a greater or less throw of the comb holder D to be
made by the cam f, and therefore a greater or less depth of tooth to be cut according
to the shape of the back of the comb.
Having now described and particularly ascertained the nature of my said Inven-
tion, and the system, mode, or manner in or under which the same is or may be
used or practically carried into effect, I would observe in conclusion that what I
consider to be novel and original, and therefore claim as the Invention secured to
me by the herein-before in part recited Letters Patent is,-
First. The arrangement of parts constituting the improved machine for cutting
the teeth of combs, essentially as herein-before described, and illustrated in the
accompanying Drawings.
Second. The mounting the guides (B), essentially as herein-before described, and
illustrated in the accompanying Drawings, so that they turn upon the same centre
as that upon which the saw turns.
Third. The combination with the comb holder or "glands" of a shaper" (E)
for regulating the depth of cut according to the shape of comb, essentially as herein-
before described, and illustrated in the accompanying Drawings.
Fourth. The arrangement of mechanism, essentially as herein-before described,
and illustrated in the accompanying Drawings, for giving a variable sideway move-
ment to the comb holder or "glands" according to the number of teeth which are
to be cut.
In witness whereof, I, the said John Lumsden Nelson, have hereunto set my
hand and seal, this Twenty-ninth day of March, in the year of our Lord
JOHN LUMSDEN NELSON. (L.S.)