Improvements in Gear Cutting Machines.
Year: 1898

page_text: Date of Application, 14th Nov., 1898-Accepted, 5th Aug., 1899
COMPLETE SPECIFICATION.
Improvements in Gear Cutting Machines.
I, CHARLES DE LOS RICE, of No. 24, Marshall Street, in the City of Hartford,
County of Hartford, State of Connecticut, United States of America, Mechanical
Engineer, 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 in general to gear cutting machines and more-especially
to machines in which a template or former or master gear or tooth is used, in
contradistinction to machines which are intended to generate a tooth in accordance
with a theoretical form, but it will nevertheless be understood, particularly as
this description proceeds, that various features of the invention are capable of
a general application, and are not of necessity restricted to any particular type
of machine. For the purpose of enabling the nature of the invention to be
clearly understood, the same is illustrated in the accompanying drawings and
described herein as applied to a machine for cutting bevel gears. In that
machine a master (either a complete gear or a single tooth) of the desired form
and a blank of suitable size, which may or may not have been previously
roughed out, are secured together upon a spindle, the blank being presented to
a suitable cutting tool and the master being pressed against a stationary guide.
A work- or master-controlling weight is applied to the spindle so that the master
shall be pressed against the stationary guide with sufficient pressure and the
spindle is mounted upon a carrier to which movement is iniparted about an
axis which intersects the axis of the spindle. The carrier also receives a vertical
movement to bring the blank and the master into operative relation with the
cutter and the stationary guide respectively. A suitable indexing mechanism is
also applied to the spindle above referred to. The various working parts above
mentioned, with the exception of the cutter, receive their motion from or are
controlled and checked in their motion by cams which rotate synchronously but
have their effective portions so arranged as to produce or permit the several
movements at the proper time. The cutter, or cutting tool, is shown both
as a rotary cutter and as a reciprocating cutter and in order to compensate for
the thickness of the cutter and for the thickness of the guide when cutting
opposite sides of a tooth, the cutter is so supported as to be capable of a lateral
displacement to the necessary extent. During the operation of the machine the
work, starting from its initial and lowest position, first rises rapidly to approach
the cutter and then continues to rise slowly during the cutting to the required
depth then it receives a slight rotative movement about the axis of the blank
for side cutting to the finish line of the tooth, and next a combined rotative and
partially revolving or swinging movement about the vertical axis for the forma-
tion of the tooth curves: this is followed by a quick return of the same motion
and a quick drop to the lowest point. The last step is the indexing operation
which brings the corresponding side of the next tooth into position. When all
of the teeth have been formed on one side certain parts of the machine are
reversed or shifted and the operations are repeated on the opposite side of each
:

page_text: tooth. The details of construction and operation will be more fully explained
hereinafter. The machine here shown and described has been specially designed
with especial reference to absolute accuracy in its work, the finished gear con-
forming exactly to the master and profiled therefrom, although on a different
scale, and to efficiency as regards the quantity of work done. To this end
devices are provided for securing the utmost exactness in adjustment of parts;
absolute immovability of those parts which should remain stationary during
operation is provided for and the chance for wear between working parts is reduced
to a minimum; the reliability of the cutter is also assured. The work and the
template or former or master gear or tooth are secured to the same member so
that there is no possibuity of any wear or lost motion between the two; finally
the moving parts have a very slow movement and a very limited action making
it possible to design them with such liberal proportions as to reduce both wear
and elasticity to a minimum.
In the drawings, in which the machine above referred to and certain modifi-
cations of some of its parts are illustrated,-
Figure 1 is a front view of the machine, a part of the indexing wheel being
broken away
to show other parts beyond it:-
Figure 2 is a side elevation of the machine viewed from the left in Figure 1;
Figure 3 is a vertical section of the machine, substantially in the plane of the
axis of the lower cam shaft;
Figure is a horizontal section on the irregular plane indicated by the
line 44 of Figure 3;
Figure 5 is a detail view in front elevation illustrating the indexing mechanism
and the connection of the work-controlling weight therewith;
Figure 6 is a rear elevation of some of the parts shown in Figure 5 with the
addition of the centering device;
Figure 7 is a plan view of the cutter and its driving, carrying and shifting
devices;
Figure 8 is a right hand elevation of the upper, rear portion of the machine,
illustrating the devices shown in Figure 7 and the belt shipper releasing
mechanism;
Figure 9 is a detail view of the cutter shifting weight and some of the parts
with which it co-operates;
Figure 10 is a view similar to Figure 1, but showing a machine having a
single master gear tooth in place of a complete master gear, and having a
reciprocating cutter in place of a rotary cutter;
Figures 11 and 12 are detail side and plan views of some of the parts shown in
Figure 10.
The machine represented in the drawings (Figures 1 to 9 inclusive) receives
power through a belt wheel A on a short shaft A' which rotates in suitable
bearings on a carrier hereinafter referred to. From the shaft A¹ power is trans-
mitted by a chain A2 and sprocket wheels A3 A4 to a worm shaft A5 which is
mounted in suitable bearings in the standard of the machine and engages a worm
wheel A on a vertical shaft A7. A second shaft A8 is driven from the shaft A7
at the same rate, the two shafts A7 and A8 bearing cams which actuate certain
of the working parts hereinafter referred to.
Upon one of the cams, B, secured to the lower cam shaft A8, and termed, with
reference to its function, the work-lifting cam, rests a carrier C, which supports
the blank to be cut and the master gear or tooth or template or former, moves
them to operative relation with the cutter or guide, and permits them to have,
in cutting bevel gears, a partial revolution, or, as it is hereinafter described,
a swinging movement about an axis vertical to the axis of the blank and master
gear, as well as a rotative movement on the last named axis. The carrier, in
the machine shown, comprises a vertical shaft supported in suitable bearings,
and suitable bracket arms to receive the bearings for the work spindle. A block Ci
carrying a roller C² to rest upon the cam B, and prevented from rotative move-

page_text: ment by a guide or guides C3 forms a thrust bearing to receive an adjustable step
bearing C which is threaded into the lower part of the carrier so as to permit
of adjustment of the carrier with respect to the cam, and is secured in adjusted
position by a set screw C. In the arms of the carrier are rotatably mounted
eccentrically bored bushings which form the bearings for the work spindle or
holder D. The eccentricity of the bushings is precisely the same and they can
be adjusted equally (being graduated if necessary) in the split clamping yokes
in which they are mounted so as to bring the axis of the work spindle or
holder 1 exactly into the plane of the vertical axis about which the carrier
swings. One of the bushings, as C, is cut away to receive a friction shoe (8
the pressure of which upon the work spindle can be adjusted by a set screw C.
The object of this friction shoe is to prevent too free rotation of the work spindle,
particularly during the cutting to depth and during the indexing operation.
The blank to be cut and the former are connected to move together during
the cutting and for this purpose the work spindle or holder is adapted to have
securely fastened thereto the blank, which is represented at D', and the master
gear or tooth or template or former, which is represented at D2, as a full gear,
although, as will be explained hereinafter, a single master gear tooth may be
substituted for the full gear if the character of the work renders it desirable.
The relative positions of the blank and the master, which term is used herein
as a general term without regard to the particular character of the part, will
depend upon the size which the gear to be cut is to have relative to the master.
In the drawings, the gear to be cut is represented at about one-fifth of the
diameter of the master, being relatively nearer to the apex of the cone in which
the blank and the master are contained, that is to say, the pitch cone of the gear,
the said apex, lying in the axis about which the carrier swings. Obviously,
if the gear to be cut is to be larger than the master, the blank will be placed
further away from this apex than the master. Any suitable means may be
employed to secure the blank and the master to the work spindle so that there
shall be no possibility of wear or lost motion between them, but that both shall
move as one part during the cutting, although relative movement may be per-
mitted between operations on successive teeth. As represented in the drawings,
the blank may be held by a bolt D3 which passes through the tubular spindle,
and the master may have a split hub, as shown at D*, adapted to be clamped upon
the spindle.
At the outer end of the work spindle or holder 1) is secured rigidly the index-
ing wheel E which is provided about its periphery with a double row of pro-
jections e, which are staggered circumferentially for a purpose to be described,
and is also provided, in its peripheral flange, with a series of notches e¹.
Means are provided for imparting to the work spindle a rotative tendency in
order to press the working face of the master against the guide, and it is desirable
that such means shall have such an engagement with the work spindle that
the latter may be turned from time to time to bring a fresh surface of the blank
to working position. The means shown for imparting to the work spindle this
rotative tendency comprise a work- or master-controlling weight or weighted
arm F which is pivotally secured to a sleeve or plate F¹ which is mounted for
convenience upon the hub of the indexing wheel E, a friction ring f being
interposed between the indexing wheel and the sleeve or plate, while a nut fi
is applied. to the work spindle D to bear against said sleeve, being held by a
lock nut. The master-controlling weight is pivoted to the sleeve at a point
substantially above the axis, and is adapted to rest upon either one of two steps F2
which are formed on the respective sides of the sleeve F¹, each being provided
with an adjustable bearing stud. The weight is permitted to rest upon one or
the other of these steps according to the side of the tooth which is being finished.
Connection between the master-controlling weight and the work spindle I)
or the master is effected through an arm F3 extended from the sleeve F¹ and

page_text: carrying a plunger latch F which is adapted to engage the notches e¹ in the
peripheral flange of the indexing wheel E. The latch is released at the proper
time during the descent of the carrier, to permit the operation of the indexing
mechanism, by the collision of a laterally projecting pin ft with a suitable stop
carried on the fixed framework or standard of the machine. The stop which is
represented at F in the drawings is arranged to serve not only for the purpose
of releasing the indexing wheel from the work- or master-controlling weight,
but, before this release is actually effected, to force the indexing mechanism
to its true position so as to insure the work being in exactly the correct position
with respect to the cutter when it rises again. For this purpose the stop is
formed of two laterally adjustable blocks having their proximate sides inclined
toward each other. The bottom of the V-notch formed by the two blocks serves
as the seat against which the releasing pin f strikes as the carrier descends.
Before the indexing mechanism is released, however, and while one side of the
tooth is being finished, the release pin fwill be positioned on one side of the
V-seat or notch, and on the opposite side while the other side of the tooth is
being finished, thus throwing the center line of the arm F and latch F4 a
little off from the perpendicular line in each case, but to the same distance. This
distance corresponds to the distance of the center of the recess between two gear
teeth from the perpendicular plane which passes through the axis of the work
spindle or holder, which distance is one-half the thickness of the cutter, and
as this distance will vary inversely with the number of teeth of a given pitch in
the gear to be cut, the adjustability of the two parts of the stop permits
the necessary variation of the distance of the release pin f from the vertical
central plane to be effected.
It will be understood that when the pin ft, in the downward movement of
the carrier, strikes the bottom of the notched stop F, it will be held so that in
the further downward movement of the carrier the latch F will be withdrawn
from the notch e' in the flange of the indexing wheel E thereby permitting said
wheel to be turned. During the first part of the downward movement the pin f
will strike one or the other of the inclined sides of the notch in the stop 15,
thereby rotating the indexing wheel to a true position with respect to the
corresponding side of the next tooth, should it have departed therefrom. During
operation upon the side of the tooth the centre line of the same tooth stands
half the thickness of the tooth to one side of the perpendicular plane which
passes through the axis of the indexing wheel and is the plane of cutting, and
the pin must consequently stand as much to the other side of the same plane,
which position is determined by the inclined side of the stop F. Since the
thickness of teeth may vary in different sizes of gears, the blocks which form
the stop must be adjustable as described.
The work-lifting cam B is so shaped as to cause the carrier to rise rapidly at
first, to cause the work to approach the cutter, and then to rise slowly for a short
distance while the cut is carried to the required depth. In order to prevent the
work or master-controlling weight from imparting a rotative tendency to
the work spindle during the rise of the carrier and the cutting to the required
depth, which would prevent the cutter teeth from passing through the slot (if
already roughed out) between the teeth equi-distant from the center line of each
tooth and might therefore result in the breaking of the cutter teeth by premature
contact with the work during its rapid rise, provision is made for lifting the work-
or master-controlling weight or supporting it during the rise of the carrier, so that
it shall not rest upon the step which is connected to the work spindle F.
The means referred to comprise a cam F6 on the shaft A8, which is timed exactly
with the work lifting cam B and, through a rod F7, cross arm F, and plungers Fº,
one at each side of the axis of the work spindle and in line with the corresponding
position of the weight arm, supports the weight or lifts it from the steps F
during the entire rise of the carrier. When the rise of the carrier has been

page_text: completed the weight-lifting cam F permits the plungers F to descend and
the weight F to rest upon one or the other of the steps F, so that a rotative
tendency shall be imparted to the work spindle during the side cutting.
For the proper side forming cut (in cutting bevel gears) the work should have
a lateral movement in the arc of a circle about the vertical axis in which the
apex of the cone of the work lies, and suitable mechanism, as will be presently
described, may be provided for this purpose, as well as to prevent the master-
controlling weight, which is no longer supported by the plunger F, from receding
too rapidly and thereby overburdening the cutter, although the weight alone,
through the co-operation of the curved surface of the master with the guide, may
produce the lateral as well as the rotative movement, in which case the mechanism
to be described, if employed, merely checks the action of the weight. If this
mechanism is not employed, it will be understood that the work-spindle would be
returned to central position by hand after the operation upon one tooth and in
preparation for the operation upon the next.
Two cams G are secured to the vertical shaft A', and motion is communicated
from one cam or the other, according to the side of the teeth which is being
finished, to the laterally movable or swinging carrier, by transmitting devices of
which there are two sets, either one of which can be engaged with or disengaged
from the carrier as may be required. As the two sets of transmitting devices are
precisely alike, the one lying slightly above the other, a description of one will
suffice for both. A bell lever G, carrying a roller G2 to bear against the cam,
is pivoted to the standard of the machine, the roller being held against the cam
and the return movement of the connected parts effected by an adjustable
weight G³, connected to one arm of the lever by a chain G which passes over a
guide pulley G. To the other arm of the bell lever is connected a link G6 which is
made adjustable in length by ordinary means, such as are indicated in Figure 4,
and is formed at its free end with an open, tapering slot or slotted jaw G7, in
one side of which is mounted a spring-pressed plunger pin Gs with a rounded
head which protrudes slightly from the face of the side of the slot. In suitable
bearings in the carrier is mounted a spindle G which rests upon a segmental
track G carried by a suitable bracket secured to the fixed frame or standard
of the machine. This spindle is rotatable and also movable longitudinally in its
bearings and rests always on the segmental track Go during the swinging of the
carrier, being held down by a suitable spring G. In the plane of each of
the links G the spindle is made angular in cross section to correspond with the
slot of the corresponding link, so that when the link is made to engage the spindle,
its engagement shall be rendered certain. The bearing of the plunger pin Gs
against the side of the spindle aids in retaining the engagement and preventing
the link from working off during the movement of the parts. In order to provide
for the convenient engagement of either link with the carrier, as described above,
a segmental hand wheel G2 is mounted horizontally on the standard of the
machine and is connected, on opposite sides of its vertical axis, by links G with
the links G respectively, so that by a partial rotation of the hand wheel in
one direction or the other, one of the links G will be engaged with the carrier and
the other disengaged therefrom. Although the weight and the cam mechanism,
when both are used as here shown, produce respectively the rotative movement and
the lateral movement, it will be obvious that their relations might be reversed,
the cam mechanism, in either case, checking and controlling the action of the
weight.
Reference has been made above to the indexing operation, which follows the
return of the laterally movable or swinging carrier to its central position, the object
of such indexing operation, as is well understood, being to rotate the work
so as to bring a fresh surface into position to be operated upon.
As already
described, the indexing wheel E is secured to the work spindle and the work-
controlling weight is disconnected therefrom during the descent of the carrier C
and just prior to the beginning of the indexing operation. The indexing

page_text: cam, as indicated at E', is secured to the horizontal shaft As, and at the proper
time raises a vertically movable rod E2 which is connected at its upper end to
one end of a bell lever E. The other end of said bell lever engages a horizontal
plunger E which imparts motion, by its reciprocation, to the indexing wheel E.
In order to permit the engaging pin e² of the horizontally reciprocating plunger
to be oscillated to one side or the other in order that it may engage the pins or
projections e of one row or the other on the indexing wheel E, (the two rows
being offset just enough on the wheel circumference to permit the engaging pin e²
to pass from one row to the other according to the side of the teeth which is being
finished) said engaging pin e2 is carried on a sleeve e on the plunger E. The
sleeve reciprocates longitudinally with the plunger, but in order to prevent any
hammering action of the plunger on the indexing wheel and consequent excessive
movement thereof, the sleeve e is mounted loosely on the plunger and a spring e is
interposed between the sleeve and one of the fixed abutments e. It is obvious that
the oscillation of the sleeve e³, to bring the pin ea into line with one or the other
of the rows of projections e of the indexing wheel E will be necessary only when a
change is made from one side of the teeth to the other side of the teeth, that is,
when one set of the carrier swinging devices is disengaged from the carrier and
the other set is engaged therewith. Consequently, the movement of the shifting
hand wheel G¹ may be taken advantage of to effect the required oscillation of
the sleeve e. For this purpose the hub of the hand wheel is provided with a
cam E, shown clearly in Figure 6, which actuates the vertically movable bar E,
sliding in a suitable guideway secured to the standard. At its upper end the
bar carries a yoke, between the members of which is a horizontal slide bar Es.
The sleeve e is formed with projections e which straddle this slide bar, so that
the reciprocations of the sleeve are not interfered with, although the sleeve can
be oscillated upon its axis at any time, to cause the pin e2 to engage the one or
the other of the rows of projections on the periphery of the indexing wheel E,
whereby, through the horizontal reciprocations of the plunger E, the required
step by step rotation of the indexing wheel, and consequently of the work spindle
and the blank secured thereto, is effected.
It is obviously unnecessary to have the work- or master-controlling weight exert
a rotative tendency on the work spindle during the return of the swinging
carrier to its central position and during its drop to its lowest position. Means
are therefore provided for lifting the work-controlling weight away from the
steps on the work spindle during these periods, so that the weight shall have no
influence whatever upon the work spindle at that time and the master shall be
relieved of needless wear. The means shown comprise a cam H on the horizontal
shaft A8, which is positioned to act at the time referred to against a lever H',
pivoted on the standard of the machine. The outer or free end of this lever is
connected by the chain H2 with one end of an overhead lever H³. The other end of
this lever is also connected by a chain with the work- or master-controlling weight
or weighted lever F. The employment of flexible connections between the cam
lever and the weight permits the latter to be reversed for the cutting of the
opposite sides of the gear teeth. When the operations referred to have been
completed the cam H permits the work- or master-controlling weight F to descend
until it again rests upon the plunger F which is to support it.
The guide which co-operates with the master during the operation of cutting,
is mounted so as to be held rigidly during the cutting, to be capable of exact
adjustment to the most effective position, and to be capable also of being shifted
laterally when the change is made from one side of the teeth to the other, in
order that its second working face shall stand in precisely the same plane as did
the first working face. The extent of this lateral shifting is obviously equal to
the thickness of the guide. The guide is shown at K as a plate, the working
surface of which is a true plane with which the curved working surface of the
master co-operates, the plane of the guide coinciding with the plane of the work-
ing face of the cutter, which, in a bevel gear machine, passes through the

page_text: axis about which the work swings. The plate is secured by a bolt k, between two
plates K', having each a segmental slot and both secured to or forming part of
a laterally movable carriage K². The segmental slots permit the guide to
be adjusted to the most favorable position as regards the master. The carriage K
is mounted in a suitab.e guideway formed at the end of a bar K³ held rigidly
to the frame or standard of the machine. At each end of the guideway is mounted
a stop K, preferably in the form of a threaded stud capable of adjustment with
great nicety.
In order that the work shall be performed with absolute accuracy, it is also
necessary that the cutter shall be shifted laterally when the change is made from
one side of the teeth to the other, so as to bring its second working surface exactly
into the working plane. It is also necessary that the cutter shall be held firmly
while it is at work, in order to prevent vibratory action and chattering. The
cutter shown in Figures 2, 3, 7 and 8 of the drawings, is a rotary cutter L, and
is mounted upon a cutter head -L which is laterally movable upon a saddle L²,
which in turn is adjustable on an inclined bed plate L³ formed on or supported
by the frame or standard of the machine. The cutter head is formed with bearings
for the cutter shaft L and the short driving shaft A', with which the cutter shaft
is coupled by spur gears L. Suitable means are provided for holding the cutter
head firmly to the saddle while permitting the necessary lateral movement.
In bearings on the saddle L2 is mounted a shaft L, transverse to the direction
of movement of the cutter head, said shaft having at one end a weighted arm or
lever L, and at the other end a cam or eccentric Ls. The inner bearing brackets
for the shaft L project upwardly through slots in the cutter head L, and the
cam Ls between them is adapted to bear against bearing points on the cutter head.
These bearing points are conveniently formed by adjustable screw studs L'
which are inclined toward each other at an angle of about forty-five degrees.
The cam L is positioned upon the shaft so that the weighted lever or
arm L', when it has forced the cutter head, through the action
of the cam L8, to the limit of its movement in either direction,
shall stand at such an angle as to hold the cutter head and the cutter without
liability to vibration or chattering. At one end of the saddle is a screw threaded
stud Lio which receives, between nicely adjustable nuts L", an outwardly and
downwardly extending ear L12 secured to the cutter head L. The nuts Lu con-
stitute adjustable stops to limit the movement of the cutter head, and consequently
of the cutter, in each direction. The saddle 12 is also adjustably secured upon
its inclined bed plate, so that the cutter may be brought exactly to the position
desired.
Means are provided for stopping the machine as soon as the work has been
completed on one side of every tooth of the gear being cut, these means being
shown in Figures 1, 4 and 8. To one of the carrier swinging levers G¹ which,
as now understood, makes a complete movement for each tooth in the master
gear or in the gear to be cut, is connected a spring-pressed pawl M which engages
a ratchet wheel M¹ mounted upon a vertical stud on a bracket secured to the
standard of the machine. A shield M is arranged so that the pawl shall engage
only one tooth of the ratchet wheel at each reciprocation and shall advance
the ratchet wheel only one space. At the proper point in the ratchet wheel is
secured a cam pin M3 which, when the ratchet wheel has advanced a number of
spaces equal to the number of teeth in the gear operated upon, shall operate
suitable belt shipper releasing mechanism, such mechanism being shown in the
drawing as comprising a bell lever M4 and a lever M which is connected to the
spring or weight-actuated belt shipper, not shown, and is normally held against
the action of the weight or spring, by its engagement with the bell lever or
latch 3*, but is released when such latch or bell lever Mt is tripped by the cam
pin M³
The operation of the machine thus far described will now be clearly understood.
The master gear 12 and the blank D¹ having been_secured to the work spindle,

page_text: and the several cams B, E, F, G and H being all at their initial or zero positions,
and the cutter and guide being adjusted for work upon one side of the teeth of
the gear, while the work-controlling weight F is disposed on the corresponding
side, the first action is that of the cam B, which first raises the carrier Crapidly
to cause the work to approach the cutter L, and then more slowly while the
cutter is working to the required depth at the root of the tooth. Meantime the
cam Fraises the work- or master-controlling weight F so that it shall impart no
rotative tendency to the work spindle until the carrier ceases to rise. Then the
cam 6 permits the work- or master-controlling weight F to descend and impart
a rotative tendency to the work spindle during the side cut, the tooth
of the master gear meanwhile bearing against the guide K. Next,
while the work or master-controlling weight continues to act upon the
work spindle, the cam G regulates the movement of the carrier to finish the side
cut. Meantime the weight-lifting cam H has begun to act and, as the
work-lifting cam B permits the carrier 0 to descend, the weight-
lifting cam H takes all of the weight from the work spindle. At the same
time the cam G forces the carrier to swing back to its central position. As the
carrier approaches its lowest position the indexing mechanism is disconnected
from the work- or master-controlling weight and finally the cam E actuates
the indexing mechanism to bring a new portion of the blank to the line of
work. These several operations are repeated until one side of every tooth has
been completed, when the machine is stopped by the release of the belt shipping
mechanism. To adjust the machine for work on the other side of every tooth of
the gear, the guide K is shifted to bring its second working surface to the working
plane and the weighted cam lever L is thown over to bring the other working
surface of the cutter to the same plane. The segmental hand wheel G2 is then
shifted to bring the other swinging cam G into operative relation with the carrier C
and the work or master-controlling weight F is shifted to rest on the opposite
plunger F. This shifting of the work- or master-controlling weight causes a
slight rotative movement of the work spindle, the extent of which is governed by
the adjustment of the steps 12 and their relation to the tops of the plungers F
which receive the weight.
This slight rotative movement brings the work itself into the proper position
with respect to the cutter and the master gear into proper position with respect
to the guide.
It will be readily understood that by substituting another master of the proper
proportions, and by properly adjusting the various parts of the machine according
to the work to be performed, it is possible to adapt the machine without other
changes to the production of gears of any desired angle or shape and of any
desired size within reasonable limits, the machine being universal. It will also
be seen that the machine is a true profiling machine, reproducing in the gear cut
the exact shape of the master, so that it is possible to modify the shape of a
theoretically correct master gear tooth, to such an extent, as by rounding off the
point of the tooth, for example, as shall give the best results in practice. Further-
more, by substituting an emery wheel, for example, for the steel cutter, the
machine can be used for grinding gears to remove tool marks and to cure any
distortion that may have been suffered by the gears during the hardening process
to which they are usually subjected after being cut.
Although, especially or the cutting of small gears, it is preferable to employ
a rotary cutter, as in the form of machine already described, on account of the
greater speed with which the work can be performed, and is also preferable to
employ a complete master gear, rather than a single tooth, because a complete
master gear regulates the spacing of the teeth, which is an important considera-
tion, as well as determining the tooth curves, and also because the complete
master gear, before being used, can be mounted and run with its mating gear
and thereby proved to be of acceptable form, ensuring absolutely correct results
in the gears profiled from it, nevertheless, it is easily possible to substitute a

page_text: reciprocating cutter for the rotary cutter, whenever the size of the gears or other
considerations make such a change desirable, and it is equally possible to employ
a single master gear, tooth or former in place of a complete master
gear if the character of the work to be performed renders this
change desirable. A machine in which both of these substitutions have been
made is shown in Figures 10, 11 and 12, and will now be described, so far as
the parts just referred to are concerned; all other parts, not more particularly
mentioned hereinafter, are represented as constructed, arranged and operating in
the same manner as in the machine already described, and therefore require no
further explanation herein. As represented in the figures just referred to, the
single master gear tooth D is securely clamped in an arm projecting from a
sleeve Do which is journalled on the work spindle D. The indexing wheel E
is secured rigidly, as before, to the work spindle and is adapted for engagement
with the sleeve which supports the master gear tooth. As represented, it is
provided on its inner face with a series of notches e* for engagement with a
spring-pressed plunger latch D7 which is mounted in another arm extended from
the sleeve D. Obviously, the notches e must be spaced with perfect accuracy,
After the finishing of one side of a tooth the plunger D is withdrawn by hand to
permit of the indexing operation without the rotation of the master gear tooth
with the indexing wheel. Otherwise the operations of the machine are the same
as those already described. If the machine be used with a single master gear
tooth it would evidently be feasible to create a steel tooth for the purpose in a
most refined form, and to case-harden and burnish it if necessary so that its life
would be very great, and this one tooth could be used for different gears and in
any case would ensure the absolute similarity of all the teeth of a gear.
A reciprocating cutter may be arranged as shown in Figures 10, 11 and 12,
the tool itself, which is represented at N having its sides parallel with each
other and having a thickness great enough to insure strength but not so thick
as to interfere with the tooth next to that one being operated upon. It should
also be so mounted as to have a capacity for lateral adjustment sufficient to bring
either one cutting edge or the other into the plane of work which in cutting
bevel gears, must necessarily intersect the axis about which the work swings.
The tool N is shown as mounted in a reciprocating carrier N¹ which is connected
by a rod N with a crank pin N³ carried by a shaft N, the crank pin and the con-
nection of the rod to the reciprocating slide both being adjustable so as to make
it possible to control the action of the cutter. The slideway N is carried by an
arm No which is swiveled upon the framework of the machine, the axis of the
swivel being in a line with the apex of the pitch cone, so that the movement of
the cutter can be adjusted to be parallel with the base of the gear tooth in a gear
of any angle. In this arrangement, as well as in that previously described
the lateral feed of the blank to the cutter is effected through the lateral oscillation
of the work spindle about the vertical axis, the operation of the machine with a
reciprocating cutter head being in no respect different from the operation of
the machine with a rotary cutter. The working edge of the reciprocating cutter
moves in a fixed plane during the cutting of one side of a tooth, as does also
the working face of the rotary cutter, and the lateral feed of the work spindle is
effected and controlled in precisely the same manner and by the same mechanical
devices in both instances.
Although both forms of machines described herein are specially adapted for
cutting bevel gears, it will nevertheless be understood that the essential features
of the machine are also capable of use in cutting spur gears, the master, whether
a complete gear or a single tooth, and the work having, in such case, a lateral
movement in right lines, instead of a lateral movement in the arcs of circles. It
will also be understood that various changes may be made in the construction and
arrangement of the several parts of the machine without departing from the
spirit of the invention, and that the invention, therefore, is not to be limited
to the precise construction and arrangement of parts herein shown and described.

page_text: 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 :
1. A machine for cutting gear teeth comprising means for supporting a master
and a gear blank to rotate about a common axis and to move laterally, and a
guide for contact with said master.
2. A machine for cutting gear teeth comprising means for supporting a master
and a gear blank to have a movement of rotation about a common axis and to
have a lateral movement, a guide for contact with the master, and a weight or
equivalent means connected to said master and gear blank to press the master
against the guide with a rotative tendency.
3. A machine for cutting gear teeth comprising means for supporting a master
and a gear blank to rotate about a common axis and to move laterally, a guide
plate the working surface of which is a true plane, and means to press the
working surface of the master against the working surface of the guide plate
with a rotative tendency.
4. A machine for cutting gear teeth comprising means for supporting a master
and a gear blank to rotate about a common axis and to move laterally, a guide
plate the working surface of which is a true plane, means to press the working
surface of the master against the working surface of the guide plate with a
rotative tendency, and a cutter, the working surface of which is a true plane
lying in the plane of the working surface of the guide plate.
5. A machine for cutting bevel gear teeth comprising means for supporting a
master and a gear blank to rotate about a common axis and to swing about an axis
intersecting the first named axis, and a guide for contact with said master.
6. A machine for cutting bevel gear teeth comprising means for supporting
a master and a gear blank to rotate about a common axis and to swing about
an axis intersecting the first named axis, a guide plate the working surface of
which is a true plane lying in the plane of said intersecting axis, means to press
the working surface of the master against the working surface of the guide plate
with a rotative tendency, and a cutter the working surface of which is a true plane
lying in the plane of the working surface of the guide plate.
7. A machine for cutting bevel gear teeth comprising a spindle to which the
master and gear blank are secured, a carrier for said spindle and with which it
is movable about an axis intersecting the axis of the spindle, a stationary guide
for contact with the master, and a cutter with its working face in the same plane
with the working face of the guide and said intersecting axis.
8. A machine for cutting gear teeth comprising a spindle to which the master
and the gear blank are secured and rotatable on its own axis, a carrier having
bearings for said spindle, a stationary guide for contact with the master, a cutter
with its working face in the same plane with the working face of the guide and
said intersecting axis, a step secured frictionally to said spindle, and a weight
arranged to bear upon said step.
9. A machine for cutting gear teeth; comprising a spindle to which the master
and the gear blank are secured and rotatable on its own axis, a carrier having
bearings for said spindle, a stationary guide for contact with the master, a cutter
with its working face in the same plane with the working face of the guide and
said intersecting axis, a step secured to said spindle, a weight arranged to bear
upon said step, and a cam and intermediate devices to lift the weight from the
step.
10. A machine for cutting bevel gear teeth comprising a spindle to which the
master and the gear blank are secured and rotatable on its own axis, a carrier
movable about an axis intersecting the axis of the spindle and having bearings
for said spindle, a stationary guide for contact with the master, and a cutter.
11. A machine for cutting gear teeth comprising a holder for a master and a
gear blank rotatable on its own axis, a stationary guide for contact with the master,
a cutter, a work- or master-controlling weight connected to said holder, indexing

page_text: mechanism connected to said holder, and a connection between said weight and
said indexing mechanism.
12. A machine for cutting gear teeth comprising a holder for a master and
a gear blank rotatable on its own axis, a stationary guide for contact with the
master, a cutter, a work- or master-controlling weight frictionally connected to
sard holder, indexing mechanism connected to said holder, and a connection
between said weight and said indexing mechanism.
13. A machine for cutting gear teeth comprising a holder for a master and a
gear blank rotatable on its own axis, a stationary guide for contact with the
master, a cutter, an indexing wheel secured to said holder and having notches,
a plate secured to the holder frictionally and having a step and an arm, a
latch carried by said arm to engage said notches and a weight to bear upon said
step.
14. A machine for cutting gear teeth, comprising a holder for a master and a
gear blank rotatable on its own axis, a stationary guide for contact with a
master, a cutter, indexing mechanism connected to said holder, a radially movable
projection connected with the indexing mechanism, and a stationary V-notch for
engagement with said projection.
15. A machine for cutting gear teeth comprising a holder for a master and a
gear blank rotatable on its own axis, a stationary guide for contact with the
master, a cutter, an indexing wheel secured to the holder, an actuator for said
indexing wheel, and means to shift said actuator to cause it to engage different
points on said wheel, offset circumferentially whereby the thickness of the cutter
is compensated for in working upon opposite sides of the gear teeth.
16. A machine for cutting gear teeth comprising a holder for a master and a
gear blank rotatable on its own axis, a stationary guide for contact with the
master, a cutter an indexing wheel secured to the holder and having two sets of
teeth or projections offset circumferentially, a plunger having a pin or projection
to engage one or the other of said sets of teeth, means to reciprocate said plunger,
and means to oscillate said plunger in one direction or the other, to. bring its
pin or projection into engagement with one or the other of said sets of teeth.
17. A machine for cutting bevel gear teeth comprising a holder for a master
and a gear blank rotatable on its own axis, a carrier for said holder and with
which it is movable about an axis intersecting the axis of the holder, a stationary
guide for contact with the master, a cutter, and a cam and intermediate connec-
tions to regulate the movement of said carrier about said intersecting axis.
18. A machine for cutting bevel gear teeth comprising a holder for a master
and a gear blank rotatable on its own axis, a carrier for said holder and with
which it is movable about an axis intersecting the axis of the holder, a stationary
guide for contact with the master, a cutter, independent sets of devices to regulate
the movement of said carrier about its axis in opposite directions, and means to
engage either of said sets of devices with said carrier.
19. A machine for cutting bevel gear teeth comprising a holder for a master
and a gear blank rotatable on its own axis, a carrier for said holder and with
which it is movable about an axis intersecting the axis of the holder, a stationary
guide for contact with the master, a cutter, a link to engage said carrier, a cam
and operative connections between said link and cam, a hand wheel, and a link
connecting the first named link with the hand wheel.
20. A machine for cutting gear teeth comprising a holder for a master and a
gear blank rotatable on its own axis, a carrier for said holder movable in a
direction transverse to the axis of the holder to bring the blank into operative
relation with the cutter, a cutter, and means to move said carrier.
21. A machine for cutting gear teeth comprising a holder for a master and a
gear blank rotatable on its own axis, a carrier for said holder movable in a
direction substantially perpendicular to the axis of the holder to bring the blank
into operative relation with the cutter, a cutter, and a cam against the periphery
of which said carrier rests,

page_text: 22. A machine for cutting bevel gear teeth comprising a holder for a master
and a gear blank rotatable on its own axis, a carrier for said holder and with
which it is movable about an axis intersecting the axis of the holder, a stationary
guide for contact with the master, a cutter and means to move said carrier in a
direction substantially perpendicular to the axis of the holder to bring the blank
and the master gear into operative relation with the cutter and the guide respec-
tively.
23. A machine for cutting bevel gear teeth comprising a holder for a master
and a gear blank rotatable on its own axis, a carrier for said holder and with
which it is movable about an axis intersecting the axis of the holder, a stationary
guide for contact with the master, a cutter, a cam and intermediate connections
to swing said carrier about said intersecting axis, and means to move said carrier
in a direction substantially perpendicular to the axis of the holder to bring the
blank and the master into operative relation with the cutter and the guide respec-
tively.
24. A machine for cutting bevel gear teeth comprising a holder for a master
and a gear blank rotatable on its own axis, a carrier for said holder and with which
it is movable about an axis intersecting the axis of the holder, a stationary guide
for contact with the master, means to swing said carrier about said intersecting
axis, and a belt-shipper releasing device in operative relation with said means
and progressively actuated thereby with a step by step movement whereby the
belt shipper is released after the carrier has been swung a predetermined number
of times.
25. A machine for cutting gear teeth comprising a holder for a master and a
gear blank, a stationary guide for contact with the master on either side of the
master tooth, means to press the master against the guide, a cutter, and means
to shift the cutter sidewise in either direction to bring its working face into the
same plane with the working face of the guide.
26. A machine for cutting gear teeth comprising a holder for a master and
a gear blank, a stationary guide for contact with the master on either side of
the master gear tooth, means to press the master against the guide, a cutter, a
cutter head upon which the cutter is mounted, and with which it is movable
sidewise, and a weighted lever having a cam surface for co-operation with bearing
points on the cutter head.
27. A machine for cutting gear teeth comprising a holder for a master and a
gear blank, a stationary guide for contact with the master on either side of the
master tooth, means to press the master against the guide, a cutter, a cutter head
upon which the cutter is mounted and with which it is movable sidewise, adjust-
able stops to limit the movement of the cutter head, and means to shift the
cutter head to bring the working face of the cutter into the same plane with the
working face of the guide.
28. A machine for cutting gear teeth comprising a rotary cutter mounted on
relatively fixed bearings, a stationary guide, and a movable master connected with
the blank to be cut and engaging said guide.
29. A machine for cutting gear teeth comprising a rotary cutter mounted on
relatively fixed bearings, a stationary guide, a movable spindle to support the
blank to be cut, and a master connected with said spindle and engaging said guide.
30. A machine for cutting gear teeth comprising a rotary cutter, a support for
said cutter, a stationary guide, a movable master connected with the blank to
be cut and engaging said guide, and an inclined bed plate upon which the cutter
support is adjustable in a plane inclined to the axis of the blank and master.
Dated the Lith
f Nawamhan 1000
PHILIP M. JUSTICE,
Chartered Patent Agent, London, For the Applicant,