AN IMPROVEMENT ON FEEDING MECHANISM FOR FILE CUTTING MACHINES
Year: 1877

page_text: COMPLETE SPECIFICATION filed by Hiram Bassett Nickerson at the Office of
the Commissioners of Patents on the 4th June 1877.
HIRAM BASSETT NICKERSON, of Boston, in the County of Suffolk and State of
Massachusetts, in the United States of America. "AN IMPROVEMENT ON FEEDING
MECHANISM FOR FILE CUTTING MACHINES."
The nature of my Invention consists in combining with the feed screw of a file
cutting machine a system of eccentric gears, eccentrically adjustable, arranged in
such a manner that the velocity with which the file is fed may, if desired, be made
to vary constantly; moreover, an infinite variety of changes in the velocity may be
made.
By the use of the above device, an irregularity may be given to the cutting of
the file, so that, when completed, it will have a certain irregularity, which, though
machine cut, will render the file as good as the best hand made.
A float file cut by my improved method will not "chatter," from the fact that
the teeth, being unlike each other, will not act all in sufficient unison to produce that
effect..
A cross-cut file will not produce channels or scratches unless the teeth are
accurately aligned. Files cut with the ordinary machines are thus aligned, and thus
produce scratches.
Files cut with teeth arranged by my new method will not produce chanels or
scratches from the fact that the teeth are arranged in waved lines.
DESCRIPTION OF THE DRAWINGS.
Figure 1 is a perspective view showing the arrangement of gears used for driving
the feed screw. Figures 2 and 3 are horizontal sections through the same.
Figure 4 is a view of a cross-cut file with a series of decreasing and increasing
teeth.
Figure 5 is a plan of a float file with similarly arranged teeth.
Figure 6 is a longitudinal section showing the teeth of a float file.

page_text: In the Drawings I have shown the feed motion only of a file cutting machine as
my present Invention, as far as it relates to the machine, is confined to that part
only.
N, N³, in the Drawings represent the end of the feed screw.
D, Figure 1, represents a shaft, through which power is communicated for driving
the feed device, the gear-E serving as a medium. Upon the end N, N¹, of the
driving screw a circular eccentric M is placed, and upon this eccentric a gear L, so
that if desired, by movement of the eccentric M within L, the shaft N₁ may be
located at the center; in other words, the gear L may be used as an eccentric gear
or as an ordinary gear.
By suitable mechanical device, the eccentric M may be made fast in any position
with L that may be desired. The peice C swings upon the shaft D and serves to
hold a center P, Figures 2 & 3, upon which the gears F. and H revolves.
Q, Figure 1, is a spring which, acting upon the lower end of C, serves to press it
together with the gears F and H towards the gear L, and thus to keep the gears F,
H, and L in working relation with each other. The gear F revolves around its own
center and meshes with D. The gear H always revolves with F but is adjusted
eccentrically.
In Figures 1 and 3, the gear L is represented as holding working relation to both
gears F & H, that is, as F & H revolve together, the teeth of one or the other
would mesh with the teeth of L, thus causing L to revolve with a varying velocity..
If the gear H is made eccentric with the gear F, then E and F would both
act together upon L, and would cause it to revolve with a uniform motion, but if
H be adjusted eccentrically to F, then the action of F and H upon L will become
intermittent, and consequently the motion of L will vary in velocity. In the
Drawings L is represented as concentric with the feed screw N, N', so that if L be
moved with uniform velocity the feed will also move uniformily; but if L be moved
around upon M so as to become eccentric to the shaft N, N¹, then, though impelled
by uniform motion of F, it would give a variable motion to the feed screw N, N¼>
When it is desirable that the gear F alone shall actuate the gear L, the ring O,
Figure 3, may be removed and the gear L pressed upon the shaft of the driving
screw, as represented in Figure 2, so that it shall mesh with F only, in which
case if L be eccentric with N, N¹, the motion of the driving screw N, N¹, will be
uniform.
From the above it will be seen that I have four methods of adjustment,-
First. To have. the gear L mesh only with F, as represented in Figure 2, and to
have it concentric with the driving screw N, N', in which case a uniform motion
will be given to the driving screw; in other words, the file will be fed regularly.
Second. The gear L meshing only with F, but set eccentrically with the feed
screw N, N. This adjustment gives a regular intermittant velocity to the feed
screw, which repeats itself at every revolution.
=
Third. The gear L may be set so as to be concentric with N, N¹, and to mesh
--with both gears F&H; H-being-concentric with F; this adjustment will give an
-intermittant-velocity-which-repeats-itself-at-every revolution of-F & H, but it may
be varied in degree.
Fourth. The gear L, meshing with F&H, as above, may be set eccentric to N, N¹.
By this class of adjustment an endless. variety of velocities may be given to the
-feed.
. I will now proceed to describe the files as produced by machines which have my
improved feed motion.
By inspection of. Figure 4 it will be seen that the intersection of two set of

page_text: sets of regularly spaced, if united by a third line, be found to be arranged in a
straight line.
In my machine file the channels forming the teeth are irregularly spaced, so that
in the case of a cross-cut file, the teeth form a sinuous line, as represented by A, B,
Figure 4, so that the file will not scratch, that is, form channels, from the fact that
one tooth will not follow in the track of any other as in the case of an ordinary
machchine-cut file.
The objection to a machine-cut float file is that the teeth are so regularly spaced
that one works exactly like another, and all working in perfect harmony causes the
file to chatter or move with a rapid ricochet which interferes seriously with the
production of good work.
By my arrangement of teeth, as shown in Figures 5 and 6, this difficulty is
entirely overcome. Upon a critical examination of my file it will be seen that the
teeth which are nearest to each other are cut somewhat deeper than those which
are wider spaced. This result is incidental to the arrangement of teeth since the
metal, being finely cut, cannot offer so much resistance to the action of the chisel
as it could if coarse cut.
Having now described the construction and operation of my Invention, what I
desire to secure by Letters Patent is as follows:-
--
Claim 1st. The combination of the swinging peice C, spring Q, concentric shafts
D, P, and gears E, F, with the gears L, H, and eccentrics K and M, all arranged
substantially in the manner described.
Claim 2nd. As a new article of manufacture, a file whose surface is serrated in
two or more series of parallel lines, whose distance apart is increased or diminished
in a given ratio, in the manner shown and described.
In witness whereof, I, the said Hiram Bassett Nickerson, have hereunto set
my hand and seal, this Twenty-first day of April, in the year of our Lord
One thousand eight hundred and seventy-seven.
HIRAM BASSETT NICKERSON. (L.S.)

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