Improvements in Planing or Shaping Machines for Cutting Toothed Wheels, Sprocket Wheels, and other articles.
Year: 1897

page_text: Date of Application, 30th Mar., 1897-Accepted, 26th Feb., 1898
Improvements in Planing or Shaping Machines for Cutting Toothed
Wheels, Sprocket Wheels, and other articles.
I, EDWIN RUSSELL FELLOWS, of Springfield, in the County of Windsor and State of
Vermont, United States of America, Gentleman, do hereby declare the nature of my
nvention, and in what manner the same is to be performed, to be particularly
lescribed and ascertained in and by the following statement :-
This invention has for its object to provide a gear-cutting machine adapted to act
on a gear or other blank simultaneously at a plurality of points, to the end that the
gear-teeth may he cut more rapidly than is possible by the use of a cutter which nets
on the blank at but a single point. The invention also has for its object to enable one
cutter to cut teeth for all sizes of gears, and to generate the curve for each gear in
accordance with the size or diameter thereof.
Of the accompanying drawings, forming a part of this specification,-
Figure 1 represonts a front elevation of a gear-cutting machine embodying the
best form of my invention at present known to mo.
Figures 2 and 3 are end elevations of the same.
Figure 4 represents a plan view.
Figure 5 represents a section, partly on line 5-5 of Figure 1, looking toward the
right, and partly ou the line 5'-5' of Figure 6.
Figure 6 represents a section on line 6-6, Figure 5.
Figure 7 represents a perspective detail view.
Figure 8 represents a section on line 8-8, Figure 4.
Figure 9 represents a section on line 9-9, Figure 8.
Figure 10 represents a front elevation of the cutter-spindle and its carrier.
Figure 11 represents a sectional view of the cutter.
Figures 12 to 19, inclusive, represont plan views of the cutter and blank, showing
different stages of the gear-shaping operation.
Figure 20 represents a cutter formed to cut the teeth of a sprocket-wheel.
Figure 21 represents a modified form of cutter, and the piece formed thereby.
Figures 22 to 25, inclusive, represent a cutter of different construction from that
shown in preceding figures.
In the drawings-
a represents the supporting frame, which is provided with means for supporting
and progressively moving a blank b on which gear-teeth are to be cut, and
c represents the gear-shaped cutter, which is movable in guides on the supporting
frame, forward and back across the plane of the blank, and is fed or rotated step-by-
step after each backward or return movement, the blank being also given a pro-
gressive feed movement after each return movement of the cutter. The result of
these movements is the formation of gear teeth on the blank, as hereinafter described.
In forming teeth on circular or gear-wheel blanks, the blank is given a step-by-step
rotary feed motion, while in forming rack-teeth on straight blanks, the blank is given
a step-by-step rectilinear feed notion. I will first describe the machine as constructed
for cutting teeth on circular blanks, this being its most important function. The
blank b is secured to oue end of a spindle b', which is journalled in a bearing' b³
LD017

page_text: supported by the frame of the machine. The spindle is rotated step-by-step in unison
with the cutter, by mechanism hereinafter described. As here shown, the blank is
engaged with the spindle b¹ by means of a taper-beaded arbor b³ (Figure 8), the head b
of which is engaged with a tapered seat in the spindle (the latter being hollow), a
clamping-uut on the arbor holding the blank against a collar 6 secured to the
spindle, and a dog 67 formed on the collar and engaged with one of the arms b³ of
tbe blank. The bearing b is carried by a swinging arm b, which is connected by a
hinge with the supporting frame, so that.the spindle b¹ may be swung outwardly
from its operative position, as shown in dotted lines in Figure 4, for convenience in
applying and removing the work. The arm is secured to hold the spindle b¹ in its
operative position by a nut 612 engaged with a bolt 18 affixed to the supporting
frame and bearing on a slotted ear on the arm bº.
The cutter c, shown in section in Figure 11, is a gear-shaped body of hardened
steel, having a series of alternating projections 2 and recesses 3, the ends of said
projections constituting a series of metal-planing teeth. The outer end 4 of the
cutter is preferably slightly recessed or bevelled, to make the angle formed by its
intersection with the outer faces of the teeth slightly acute, thus giving each tooth a
suitable rake. The cutter is given a suitable clearance by bevelling the backs of the
teeth.
In Figures 5 and 11, I show the cutter formed integral with its sbank c10, while in
Figures 22 to 25 1 show the cutter made in a separate piece, having a central
orifice c¹, which receives a portion of the shank co. The said shank is provided with
a shoulder c18 at one side of the cutter, and with a threaded portion cat the opposite
side of the enlter. Between the shoulder c¹³ aud the cutter is interposed the cutter-
support cs, which is preferably a plate of the general form of the cutter detachably
mounted on the shank and rigidly backed or supported by the shoulder c¹. The
support. c bas a series of radiating projections corresponding in form to the cutter-
teeth but slightly smaller in area, said projections supporting the rear or upper ends
of the teeth against the strain exerted upon them while they are in operation, without
coming in contact with the surfaces formed by said teeth on the gear-blank, the
projections following the teeth into the blank.
cle represents a clamping-nut, which is engaged with the threaded portion of the
sbank co and may either bear directly upon the under surface of the cutter-body, or
upon an interposed plate or washer c" which in turn bears upon the under surface of
the cutter-body. When the nut ce is turned tightly to place, it co-operates with the
support c in clamping the cutter and holding it securely in place upon the shank.
I provide the cutter c and support cs with coinciding grooves, which receive a
spline c5, the shank c having also a groove which receives one side of the spline.
The support c and nut cla constitute clamping members, relatively adjustable, to
detachably secure the cutter to the shank, the cuttor being readily removable and
interchangeable with other cutters, so that cutters of different shapes and sizes may
be used with the same shank. The detachability of the support c¹ enables a different
support to be used for each size or shape of cutter. The shank and the clamping
members thereon, one of said members having radiating projections arranged to
support the rear ends of the cutter-teeth, constitute an improved cutter-head or
holder, which forms a part of my invention.
I do not limit myself to the support els made as a separate piece detachable from
the shank, as said support may be integral with or rigidly attached to the shank.
The cutter c and support c¹ may be clamped directly to the end of a suitable rotary
shaft, instead of being clamped to the tapered spindle c¹, in which case the
shoulder c would be the end of the cutter-shaft.
It will be seen that the teeth are of uniform size and shape, and that their sides
are formed to generate the curves of gear-teeth, the cutter-teeth being also arranged
in a continuous circular series, so that the cutter operates continuously in genorating
the curves of gear-teeth on a blank when the cutter is given a back-and-forth endwise
movement across the blank and the cutter and blank are rotated step-by-step, each on
a fixed axis.

page_text: The cutter is secured to a spindle c¹, which is journalled to rotate in bearings
hereinafter described, supported by a primary slide (Figures 1 and 10), said slide
being movable on fixed guides toward and froin the axis of the blank b.
The spindle c rotates in bearing c formed on the upper portion of the slide c²
and in a sliding bearing formed on a secondary slide c which is movable
between guides on the slide c³, the spindle being longitudinally movable in
the bearing ct.
The
d(Figures 5 and 6) represents a rack which is rigidly secured to the secondary
slide c and meshes with a gear-segment on a rock-shaft d' journalled in bearings
on the supporting frame, the segment d' having a sliding connection with the
shaft d by means of a spline do on the shaft. A crank-arm d³ affixed to the rock-
shaft de is connected by a rod d with a wrist-pin (Figure 2) adjustably mounted
on a crank-arm do affixed to the driving or main shaft d' of the machine.
rotation of the shaft di oscillates the segment d', through the described intermediato
mechanism, and causes the segment to impart a reciprocating endwise movement
to the spindle and cutter. The main shaft is rotated by a variable-speed driving
mechanism, which imparts a much more rapid motion to the shaft during the return
movement than during the cutting movement of the cutter. This result is accom-
plished by means of a shaft ds, which receives motion through a belt running on ono
of a series of cone-pulleys do thereon, and intermeshing elliptical gears d¹º di affixed
respectively to the shafts d' and d', said gears being connected by a link 2. The
shaft de rotates at a uniform rate of speed, dependent on the size of the pulley with
which the driving-belt is engaged, while the shaft receives through the elliptical
gears a varying rate of speed. The spindle c¹ is provided with adjustable nuts or
thrust-bearings did, one in contact with the bearing c and the other in contact
with a cross-bar c formed on the secondary slide e' above the bearing c. The slide
is provided, between the bearing and cross-bar c, with an arched brace or cross-
bar el extending across the spindle c'.
The blank-spindle is provided with a worm-gear e, which is affixed to said spindle.
The cutter-spindle c¹ is provided with a worm-gear el, which is formed on or affixed
to a sleeve (the latter being fitted to rotate in the bearing c), and is provided
with a key engaged with a groove in the cutter-spindle c¹, provision being thus made
for rotatively connecting the gear el with the cutter-spindle, and for permitting said
spindle to move endwise independently of the gear. (Figure 2) represents a cain
affixed to the main shaft d'. Motion is communicated from said cam, through the
following connections, to the worm-gear on the blank and cutter spindles :
e represents a rock-shaft journalled in fixed bearings and provided with an arm e
having a trundle-roll & bearing on the cain . To the rock-shaft e is affixed a longer
arme connected by a rod e¹o with an arin e affixed to a rock-shaft e¹s also journalled
in a fixed bearing. The rock-shaft el has an arm es, which is connected by a link e¹
with a rod e sliding in a fixed bearing elo. Said rod bears against a rod e, which
slides in a bearing es attached to the arm 69, which is independently movable, for
reasons herein before explained. The parts e¹ and el constitute a sectional rod, the
object of which is to permit the detachinent of the part contained in arm from the
pait contained in the fixed guide e, thus permitting the swinging of said arm.
The rod or section " is connected by a link 180 with one arm of a lever e10 which is
mounted to oscillate on a shaft e jourualled in a bearing on the supporting frame.
The other arm of the lever e¹ has a spring-pressed pawl (Figure 9), which
normally engages a ratchet es affixed to the shaft eo. A spring attached to the
lever el norinally presses upwardly the arm of said lever to which the link 180 is
connected, the said pressure being cominunicated to the arm e' through the inter-
mediate parts, thus holding said arm against the care and taking up lost motion
in the said intermediate parts. A supplemental pressure is exerted on the arm e' by
n spring (Figure 2) acting on a short arm on the rock-shaft e. To the shaft 20
is affixed a gear e, which is connected by an intermediate gear 29 with a gear 30 ou
a shaft having a worm e meshing with the worm-gear e on the blank-spindle b¹.
The rock-shaft e¹ has another arm e, which is connected by a link with one arm

page_text: of a lever which is mounted to oscillate on a shaft journalled in a bearing on
the slide c. The other arm of the lever is provided with a spring-pressed pawl
(Figure 3), which normally engages a ratchet 637 affixed to the shaft . A worm
affixed to the shaft engages the worm-gear e¹ on the cutter-spindle.
It will be seen that the came on the main shaft oscillates the pawls and
through the described connections, and thus causes said pawls to impart step-by-step
rotary feed movements to the blank-spindle and the cutter-spindle, these movements
being timed to occur when the cutter is separated from the blank.
I do not limit myself to a mechanism for giving the work-spindle aud cutter-
spindle rotary step-by-step feed movements, as the said mechanism may be modified
to continuously rotate said spindles at a slow rate, without departing from the spirit
of my invention, it being new with me to connect a cutter-spindle and a work-spindle
with mechanism for simultaneously rotating both parts and maintaining an operative
connection between them throughout a complete rotation of the work-spindle,
whether the rotary movement be step-by-step or continuous.
The slide c² has a limited movement on the guides c' c toward and from the work-
spindle, and is pressed away or outwardly from the work-spindle by springs ƒ ƒ
(Figures 1 and 10) bearing ou studs affixed to the slide cand on a holding-slide g.
Between the slide caud the holding-slide g is a strut ƒ³, which bears on the slide c²
and limits the movement of the slide and the cutter-spindle away from the
work-spindle.
To withdraw the cutter from the work during its return movement, I provide
means for automatically shortening the struts at the close of the forward or cutting
movement of the cutter, thus permitting the springs f to move the cutter back from
its operative path and for lengthening the strut at the end of the return movement
of the cutter, thus causing it to move the cutter back to its operative path, the cutter
therefore moving forward in one path and returning in another. To this end, I
make the strut f³ in two sectious 5 6, one having a screw-thread and the other a
tapped socket engaging said thread. The section 6 is rigidly secured to the holding-
slide g by a set-screw 7. To the section 5 is affixed a gear-segment 8, with which
meshes a gear-segment 9 splined to the rock-shaft e12 of the above-described feed
mechanism. The feed-operating cam 5 is timed to give the pawls e² their
backward movement just as the cutter reaches the end of its forward movement, and
in so doing rotates the shaft 62 and gear-segment 9 in the direction indicated by the
arrow in Figure 7, thus causing the said gear-segment to partially rotate the section 5
of the strut in the direction required to shorten the strut by the co-operation of the
screw-threads on the fixed and movable sections thereof. When the cutter reaches
the end of its roturn movement, the feed-operating cam gives the pawls ee their
forward movement, and in so doing rotates the shaft und gear-segment 9 in the
direction required to lengthen the strut.
The described backward and forward movements of the cutter and its carrier (the
slide c³) require a sliding connection between the rock-sbaft e¹³, which is journulled
in fixed bearings, and the gear-segment 9 and arms, which are supported by and
move with the slide c². I therefore provide said rock-shaft with a spline 12 (Figures
5 and 7), on which the segment 9 and arm ess are fitted to slide.
At the commencement of the operation, the cutter must be entirely outside of the
periphery of the blank. I have therefore provided means whereby the feed mechanism
inay be made inoperative, and means whereby the cutter may be advanced step-by-
step until its cent ml tooth has entered the blank to the full extent required, before
the operation of the feed mechanism.
The pawl e is provided with a handle 13, and the pawless with a handle 14,
whereby said pawls may be retracted from the accompanying ratchets, thus making
the feed mechanism inoperative, the pawls being held retracted by pins 15 on said
haudles when the handles are turned to cause the said pius to bear on the outer ends
of the levers carrying said pawls. The holding-slide g has a nut g¹, which is engaged
by a feed-screw journalled in bearings on the supporting frame. The feed-screw
has a hand-wheel g³ by which it may be rotated to move the slide g. When the

page_text: slide is thus moved inwardly toward the work-spindle, the strut forces the slide c*
and the cutter c inwardly at the same time. When the slide g is moved outwardly,
the springs f and studs cause the slide and the cutter to follow it. The
operator, after the completion of each piece of work, can withdraw the cutter from
the work-spindle, so that it will be outside the periphery of the next blank, as shown
in Figure 12, and then, by allowing the cutter to make its forward and return
movements, as above described, and moving the slide c³ forward after each returu
stroke, the cutter can be advanced until its operative teeth have entered the work
the required distance, or until the central tooth has entered the blank to the
inaximum depth required, as shown in Figure 14, after which the feed mechanism is
made operative by releasing the pawls, the rost of the operation being automatic.
The operation of generating gear-teeth on the blank by the combined feed
motions of the cutter and blank is illustrated by Figures 14 to 19, inclusive. Figure 14
shows the forin of the blank when the feed motions commence. In the succeeding
figures, the blank is shown by full and dotted lines in the position it occupies
relatively to the cutter after the feed movements of the work and cutter, and while
the cutter is making its inoperative movement, the dotted lines indicating the metal
being removed at the time. It will be understood, however, that in these views the
quantity of metal removed is considerably exaggerated, the actual quantity removed
by each pass of the cutter across the blank being too small to be represented in this
manner.
Figure 19 shows a completed tooth t, and Figures 14, 15, 16, 17, and 18 show the
successive steps involved in the generation or shaping of said tooth. These figures
make the shaping or generating operation clear, without further description. It will
be seen that spur-gear teeth of any desired form may be produced in the manner and
by the incans described, the form of the teeth cut on the blank being determined by
the form of the teeth of the cutter.
My invention is not limited to the formation of teeth on circular gears, and may
be used for shaping or generating rack-teeth. In Figures 1, 2, 3, 4, and 8, I show a
slides having a rectilinear movement in a fixed guide 8 and arranged to support a
rack-blank and present it to the cutter c. Said slide may be moved progressively to
feed the rack-blank by any suitable means, such as a gear (not shown) rotated step-
by-step by a suitablo modification of the mechanism which rotates the gear-blank b,
the slide having rack-teeth 82 to engage said gear. The operation of generating a
series of rack-teeth is practically the same as that of generating gear-teeth, the only
difference being a rectilinear instead of a rotary movement of the blank.
I do not limit myself to the details of mechanism here shown, and may use any
other suitable means for imparting to the gear-shape cutter and the blank the
necessary gear-shaping or generating movements.
The chief advantages resulting from the employment of a gear-shaped cutter
which is fed by a rotary movement on its own axia in a machine of the character
described are as follows:-
First, The cutter generates the form of the curve of each gear-tooth on the blank,
so that each tooth cut is theoretically correct.
Secondly, One size of cutter for any given pitch will cut any size of gear.
Thirdly, The operation of cutting is continuous. In ordinary automatic gear-
entting machines, there are two separate and distinct mechanisms, one for feeding
the cutter, and one for indexing the blank. Ench mechanism must be inoperative
while the other is in operation, a complication of mechanism being involved, which
is avoided by my improvement.
Fourthly, Several cutting teeth or points are in operative contact with the work
simultaneously, insuring a rapid operation.
Fifthly, The same cutter will cut either external or internal gear-teeth with equal
ease and correctness. This is an important advantage, it being very difficult to cut
internal gears correctly by any of the gear-cutting machines now in use.
I do not limit myself to a cutter of conventional gear shape,-a cutter of any form
having a circular series of cutting teeth or projections alternating with recesses, the

page_text: highest or outer portions of the feeth being substantially equidistant from the axis of
rotation of the cutter, will be within the scope of my invention.
In Figure 20, I show a cutter c³ formed to cut a sprocket-wheel, the teeth being
longer than the intervening recesses.
In Figure 21, I show a cutter c' having curved teeth or projections shaped to form
four plane surfaces c² on a blank presented to it, both the blank and the cutter
having a rotary feed movement, the cutter having also a back-and-forth movement
across the blank.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the saine is to be performed, I declare that what I
claim is
1. The combination of a metal-planing cutter having a circular series of radiating
or outwardly projecting gear-shaped metal-planing teeth, a blank-holder or support,
inéans for reciprocating one of said parts to cause the cutter to plane the blank, and
means for changing the relative positions of said parts to cause the said teeth to act
successively at different points on the blank and generate the curves of gear-teeth
thereon.
2. The combination of a gear-shaped metal-planing cutter having external gear-
shaped teeth arranged in a circular series, a blank-holder, cutter-operating mechanism
having provisions for progressively rotating said cutter to make its teeth successively
operative and for reciprocating the cutter to give the operative teeth their cutting
and return movements, and mechanisin for feeding the blank.
3. The combination of a blank-holder, a gear-shaped metal-planing cutter, a spindle
supporting said cutter, bearings supporting said spindle, means for rotating the
spindle in said bearings to feed the cutter, meaus for reciprocating the spindle and
its bearings to give the cutter its operative movements across the blank, and mechanism
for feeding the blank.
4. The combination of a blank-holder, a gear-shaped metal-planing cutter, a spindle
supporting said cutter, bearings supporting said spindle, means for reciprocating the
spindle and its bearings to carry the entter forward and back across the blank, means
for changing the path of the spindle relatively to the blauk-holder after each stroke
of the cutter, to alternately project and retract the cutter, and means for rotating
the cutter.
5. The combination of a blank-holder, a gear-shaped metal-planing cutter, a spindle
supporting said cutter, bearings supporting said spindle, means for reciprocating the
spindle and its bearings to carry the cutter forward and back across the blank, means
for changing the path of the spindle relatively to the blank-holder after each stroko
of the cutter, to alternately project and retract the cutter, means for imparting a
progressive lateral movement to the spindle and its bearings to advance it into the
blank, and means for rotating the cutter, the said last-named means having provision
for being made temporarily inoperative.
6. The combination of a gear-shaped metal-planing cutter, a spindle supporting
the same, a blank-holder, a driving-shaft, mechanism for imparting a rotary motion
from the said shaft to the cutter-spindle, and mechanism for imparting a reciprocating
motion to the spindle, the last-mentioned mechanisin having provision for varying
the speed of the reciprocating movement after each stroke.
7. The combination of a gear-shaped metal-planing cutter, a spindle supporting
the same, a blank-holding spindle, a driving-shaft, connections intermediate the
said shaft and spindles for positively rotating the spindles in unison, and connections
intermediate the driving-shaft and cutter-spindle for imparting a reciprocating
motion to the latter.
8. The combination of a gear-shaped metal-planing cutter, a spindle supporting the
same, a blank-holding spindle, a rock-shaft el intermediate the driving-shaft and
spindles, connections between the rock-shaft and driving-shaft whereby the rock-
shaft is positively oscillated, and connections between the rock-shaft and spindles for

page_text: imparting positive rotary movements to the spindles in unison, and connections
between the driving-shaft and cutter-spindle for reciprocating the latter.
9. The combination of a blank holder, a gear-shaped metal-planing cutter, a spindle
supporting the cutter, a secondary slide supporting the spindle and movable to
reciprocate the spindle longitudinally, a primary slide supporting the secondary slide
and movable toward and froin the axis of the blank-holder, uechanism for reciprocating
the secondary slide and spindle, an adjustable connection between the primary slide
and the holder g, and mechanism for adjusting said connection to vary the position
of the primary slide.
10. The combination of a gear-shaped metal-planing cutter, a rotary spindle
supporting the cutter, a rotary blank-holding spindle, gearing adapted to impart
rotary motion to said spindles, pawls and ratchets adapted to operate said genring,
and means for simultaneously oscillating said pawls.
11. The combination of a gear-shaped metal-planing cutter, a rotary spindlo
supporting the cutter, a rotary blank-holding spindle, and a swinging bearing for
the last-named spindle adapted to displace the spindle from its operative position.
12. A metal-planing cutter having outwardly projecting or radiating metal-planing
teeth the backs of which are formed at a slight clearance angle with the axis of the
cutter while their sides are formed to generate the curves of gear-teeth when the
cutter aud gear-blauk are relatively moved as described, said cutter-teeth being of
uniform size and shape and arranged in a continuous circular series, whereby the
cutter is enabled to operate continuously in generating the curves of gear-teeth on
blauks of different sizes, as set forth.
13. A metal-planing cutter having outwardly projecting or radiating metal-planing
teeth the backs of which are formed at a slight clearance angle with the axis of the
cutter, said teeth being of uniform size and shape and arranged in a continuous
circular series, combined with a shank adapted for engagement with a cutter-operating
device or mechanism and having provisions for detachably holding or clainping the
cutter, said shank having its axis coincident with the axis of the cutter.
14. A metal-planing cutter comprising a hub or body having a central orifice and
a continuous circular series of outwardly projecting metal-planing teeth, the backs of
which have a slight clearance angle; combined with a shank or spindle formed to
removably enter said orifice and having a shoulder at the rear side of the cutter; an
inner clamping member or plate perforated to receive the shank and supported by
said shoulder at the rear side of the cutter, said member having projections coinciding
with the teeth of the cutter; an outer clamping member adjustably connected with
the shank and adapted to engage the outer side of the cutter; and means for locking
the inner clamping member and cutter together to prevent independent rotary
movement of either.
15. The combination of a gear-shaped metal-planing cutter having a central orifice
and a groove communicating therewith; a shauk having a shoulder and a threaded
portion; a detachable supporting or clamping member rigidly backed by said shoulder
and provided with projections coinciding with the cutter-teeth, and with a centml
orifice and groove coinciding with the orifice and groove of the cutter; a clamping-
nut engaged with the threaded portion of the shank; and an annular plate or washer
interposed between the nut and cutter.
Dated this 20th way of repruary 1031.
EDWIN RUSSELL FELLOWS.
Haseltine, Lake & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.