Improvements in Gear Cutting Engines.
Year: 1893

page_text: Date of Application, 22nd Feb., 1893
Complete Specification Left, 11th Nov., 1893-Accepted, 10th Feb., 1894
PROVISIONAL SPECIFICATION.
Improvements in Gear Cutting Engines.
I, ULRICH EBERHARDT, of 97, New Jersey Railroad Avenue, in the City of
Newark, County of Essex, State of New Jersey, United States of America,
Engineer do hereby declare the nature of this invention to be as follows:-
This invention relates to certain improvements in gear cutting engines which are
commonly used to form teeth in metallic blanks, and which are provided with a
worm wheel and worm having change wheels to rotate the blank intermittingly
after each movement of the cutter.
In such machines a locking device, operated by hand or automatically, is
provided to lock the first one of the change wheels uniformly in a fixed position
after each shift of the worm wheel, and one improvement in the present invention
consists in the combination with the worm shaft, of an auxiliary shaft connected to
the said change wheels, and additional change wheels connecting the auxiliary
shaft with the worm shaft to vary the operation of the lock upon the worm and
the blank.
By this improvement the same change wheels may be made to produce a variety
of movements in the worm wheel and the blank.
Another improvement consists in the combination with the carriage for the rotary
cutter, of a pipe for projecting a cooling liquid upon the cutter, and a passage
through the carriage and the bed sustaining the same, with a pau beneath such
passage to receive the liquid and the chips cut from the blank.
The pan is preferably provided with a strainer in the bottom to separate the
liquid from the chips, and a pump is provided to elevate the liquid again to the
cutter; by which means a lubricant may be applied continuously to the cutter
without waste.
Another improvement adapts the machine for "hobbing" a worm wheel with a
spiral cutter or "hob," and consists in the connection of the arbor which drives the
cutter, with change wheels which drive the worm wheel, by suitable shafts and
gearing; so that the worm wheel and the blank which is driven thereby may be
rotated simultaneously with the cutter. The blank is prepared to form the desired
worn wheel, and may, with this arrangement, be placed in the machine and the
teeth cut directly in the same by the continued rotation of the hob and the blank,
the blank being moved, by a suitable adjustment of the change wheels, a space
equal to one tooth for each rotation of the hob.
In the present invention a shaft is extended across the carriage which sustains
the hob and is connected at one end with the arbor which drives the hob, and at
the other end with the change wheels which rotate the worm.
Another improvement consists in a certain construction of the bearings for the
arbor of the cutter or hob.
The bearings consist in round holes formed in the solid metal of the carriage
upon opposite sides of the aperture in which the cutter is to swing, and the arbor
is divided transversely between the two bearings, so that one end of the arbor may
be moved longitudinally to apply the cutter or hob to the other portion of the
arbor which remains in the aperture. The two portions of the arbor are connected
by a threaded joint, and the movable portion of the arbor, when screwed fast to the
other portion, operates to clamp the hub or cutter firmly upon the arbor. By this
construction the bearings may be made integral with the carriage and thus hold
the orbar more rigidly

page_text: Another improvement consists in the combination, with the spindle bearing
which carries the mandrel for the blanks, of a goose neck attached to such bearing,
and provided with an outboard bearing for such mandrel.
The spindle bearing and outboard bearing are preferably formed with laterally
removable caps to permit the mandrel to be removed from the bearings laterally.
Another improvement consists in a feed screw attached to the cutter carriage, a
rotary nut for propelling such screw, means for rotating the nut automatically to
feed the cutter through the blank, a laterally projecting crank shaft and bearing
adjacent to the nut, and gears connecting the shaft and nut to turn the nut by
hand.
Another improvement consists in the application of reversible gearing to the nut,
with means to actuate the same automatically after each forward movement of the
cutter, to retract the cutter from the blank; and a cast iron casing enclosing such
reversible gearing and provided with the bearings for the reversible gearing.
Another improvement relates to the raising and lowering of the spindle bearing
in a vertical column to and from the cutter, the bearing being provided with a
screw to raise and lower the same, and such screw being provided with a rotary
nut having reversible gearing connected therewith to turn the same in opposite
directions. Such gearing is driven by a belt and pulley, so that the spindle
bearing may be raised and lowered by power, and the nut is provided also with
hand gearing to adjust the spindle bearing more accurately when the belt is
detached.
Dated this 22nd dor of Dahoma 1000
J. C. CHAPMAN, C.P.A.,
Filing Agent.
COMPLETE SPECIFICATION.
Improvements in Gear Cutting Engines.
I, ULRICH EBERHARDT, of 97, New Jersey Railroad Avenue, Newark, Essex
County, State of New Jersey, United States of America 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 to certain improvements in gear cutting engines which are
commonly used to form teeth in metallic blanks, and which are provided with a
worm wheel and worm having change wheels to rotate the blank intermittingly
after each movement of the cutter.
In such machines a locking device, operated by hand or automatically, is
provided to lock the first one of the change wheels uniformly in a fixed position
after each shift of the worm wheel, and one improvement in the present invention
consists in the combination with the worm shaft, of an auxiliary shaft connected
to the said change wheels, and additional change wheels connecting the auxiliary
shaft with the worm shaft to vary the operation of the lock upon the worm and
the blank.
By this improvement the same change wheels may be made to produce a variety
of movements in the worm wheel and the blank.
Another improvement consists in the combination with the carriage for the
rotary cutter, of a pipe for projecting a cooling liquid upon the cutter, and a
passage through the carriage and the bed sustaining the same, with a pan beneath
such passage to receive the liquid and the chips cut from the blank.
The pan is preferably provided with a strainer in the bottom to separate the
liquid from the chips, and a pump is provided to elevate the liquid again to the
cutter; by such means a lubricant may be applied continuously to the cutter
without waste,

page_text: Another improvement adapts the machine for "hobbing a worm wheel with a
spiral cutter or "hob," and consists in the connection of the arbor which drives
the cutter by means of a suitable shaft and gearing to the change wheels which
drive the worm wheel, so that the worm wheel and the blank which is driven
thereby may be rotated simultaneously with the cutter. The blank is prepared to
form the desired worm wheel and may, with this arrangement, be placed in the
machine and the teeth cut directly in the same by the continued rotation of the
hob and the blank, the blank being moved, by a suitable adjustment of the change
wheels, a space equal to one tooth for each rotation of the hob..
In the present invention a shaft is extended across the carriage which sustains
the hob and is connected at one end with the arbor which drives the hob, and at
the other end with the change wheels which rotate the worm.
Another improvement consists in a certain construction of the bearings for the
arbor of the cutter or hob.
The bearings consist in round holes formed in the solid metal of the carriage
upon opposite sides of the aperture in which the cutter is to swing, and the arbor
is divided transversely between the two bearings, so that one end of the arbor
may be moved longitudinally to apply the cutter or hob to the other portion of
the arbor which remains in the aperture.
The two portions of the arbor are connected by a threaded joint, and the
movable portion of the arbor, when screwed fast to the other portion, operates to
clamp the hob or cutter firmly upon the arbor. By this construction the bearings
may be made integral with the carriage and thus hold the arbor more rigidly.
Another improvement consists in the combination with the spindle bearing
which carries the mandrel for the blanks, of a goose-neck attached to such bearing,
and provided with an outboard bearing for such mandrel. The spindle and
outboard bearing are preferably formed with laterally removable caps to permit
the mandrel to be removed from the bearings laterally. Another improvement
consists in a feed screw attached to the cutter carriage, a rotary nut for propelling
such screw, means for rotating the nut automatically to feed the cutter through
the blank, a laterally projecting crank shaft and bearing adjacent to the nut, and
gears connecting the shaft and nut to turn the nut by hand.
Another improvement consists in the application of reversible gearing to the nut,
with means to actuate the same automatically after each forward movement of the
cutter, to retract the cutter from the blank; and a cast iron casing enclosing
such reversible gearing and provided with the bearings for the reversible
gearing.
Another improvement relates to the raising and lowering of the spindle bearing
in a vertical column to and from the cutter, the bearing being provided with a
screw to raise and lower the same, and such screw being provided with a rotary
nut having reversible gearing connected therewith to turn the same in opposite
directions.
Such gearing is driven by a belt and pulley, so that the spindle bearing may be
raised and lowered by power, and the nut is also provided with hand gearing to
adjust the spindle bearing more accurately when the belt is detached.
These improvements are illustrated in the drawing in a machine having a
horizontal bed with a cutter head movable upon the top of the same, and a column
with a mandrel head adjustable vertically thereon to carry the mandrel for
rotating the blank. Such mandrel head carries a worm wheel, a worm and change
wheels for rotating the blank intermittingly.
In the drawing, Fig. 1 is a side elevation of the machine with the parts upon
the mandrel A' in section where hatched. Fig. 2 is a plan of the machine with
the column in section and the mandrel head and its attached worm wheel removed,
leaving only the bearings for the worm shaft. Fig. 3 is a rear elevation of the
machine; Fig. 4 is a front elevation of the casing for the feed gearing with the
door open; and Fig. 5 is a side elevation of a mandrel with a removable
bushing B upon its point.

page_text: A designates the bed surrounded at the base by a pan B10 and having cutter
head D fitted movably to the top.
A feed screw a is secured to the cutter head D and projected through a rotary
nut 6 mounted in bearing at the outer end of the bed and provided with a feed
gear c.
The mandrel bearing F carries the mandrel G upon the outer end of which is
fixed a chuck B to grasp the mandrel A¹. A frame G¹ is fixed to the rear end of
the bearing F to carry the bearings G2 of the worm shaft I, and to support the
studs for the primary change wheels I. Upon the frame G¹ is fixed a bearing G³
for an auxiliary shaft I which is connected with the worm shaft I by secondary
change wheels 1. The mandrel hearing is adjustable vertically upon the column E
to adjust the blank A to and from the cutter O. The auxiliary shaft I and the
secondary change wheels I enable the operator to vary the rotation of the worm
very widely with the usual change wheels I, and to thus cut gears of different
pitches with fewer of such change wheels. Two auxiliary shafts may be used, if
needful, for great variations.
Separate trains of gearing are required to actuate the feed nut, the cutter
spindle, and the worm wheel H; and these trains are conveniently actuated by
means of a shaft J¹ which is mounted in bearings attached to the bed, so that the
machine is complete in itself, and requires merely the application of a single belt
to a single pulley for operating all its parts. To support the said shaft J'a
bracket Kis projected from the side of the bed near the rear end, and the
Dearings J for the shaft are provided one upon the outer end of the bracket and
the other upon the bed in line therewith.
A bearing K² is affixed to the inner bearing J and a shaft L is journalled therein
and connected by bevel gears with the shaft J. The shaft L is extended along the
side of the bed to a casing M which is shown enclosing the gearing for the nut b
which actuates the feed screw a.
A shaft dis mounted in bearings d' within the casing and is provided with
a clutch sleeve e having a gear c' thereon, engaging with the wheel cupon the nut.
At one end of the clutch sleeve a worm wheel is fitted to the shaft, and at the
opposite end a spur wheel n, both wheels being fitted to turn loosely upon the
shaft d and provided with teeth el to engage similar teeth. upon the clutch.
The spur wheel n is provided with a sleeve n extended through the inner face of
the casing and supported in a bearing upon its outer side, such bearing being
recessed into the front end of the bed A. The casing is provided with a bearing
for the shaft L, which is connected with the spur wheel n by intermediates P. The
intermediates turn upon bolts y secured in bosses y' upon the rear side of the casing.
The shaft L is also connected with the worm wheel by a worm j, bevel wheels k,
and change wheels m.
Bearings 9 are provided to sustain the worm shaft q', and a bearing is attached
by ribs w to the bearing 1, to support a shaft u which carries one of the bevel
wheels and one of the change wheels m.
An adjustable frog r is provided to sustain the intermediate wheels m', which
are required to connect the change wheels m, when they are properly adjusted, to
produce the desired speed in the worm. A clutch lever g, shown in Fig. 1 is
provided to shift the clutch, which may be done automatically in the manner
common in such constructions.
The worm wheel operates to feed the cutter slowly into the blank, but when
the clutch is shifted to the wheel n the nut rotates in the opposite direction at a
higher rate of speed to retract the cutter quickly.
The change wheels m form part of the train connecting the nut with the driving
shaft J permitting the feed to be operated at a variable rate of speed, while the
wheels n and reverse the screw quickly at a uniform rate of speed. The bearings
for the shaft L, shaft u, shaft d and shaft g, are cast integral with the casing M, as
shown in Figs. 2 & 4, which holds the parts firmly in their desired relation, and
protects the various wheels from derangement.

page_text: An aperture M2 is provided in the front of the casing to remove the change
wheels from the shafts / and u, and to adjust the frog r. An aperture O' is formed
in the top of the bed A coincident with the aperture O¹ in the cutter head, and
long enough to receive the chips discharged by the cutter as the head moves back
and forth upon the ways C.
A pipes for discharging the cooling fluid upon the cutter, is shown in
Figs. 1 & 2, connected by a flexible hose with a pump s¹; which is set in
the pan B10.
A passage with a sloping shute S is shown extending from the rear edge of the
opening O downward through the bed toward the front end of the same, to direct
the chips and fluid into a removable trough T.
An opening is formed in the front end of the bed to insert the trough, and a
lip So is formed upon the end of the shute above the bottom of the pan, under
which lip the end of the trough may be inserted. A perforated false bottom T' is
inserted within the trough T, and outlets t are formed below the false bottom.
The pump s¹ draws the liquid from the pan, and supplies the cutter over and over
with clean fluid.
A goose-neck Fis projected horizontally from the mandrel-head F, and a vertical
brace F2 is projected upward from the outer end of the bed and connected with the
outer end of the goose-neck to steady the same.
A bolt is inserted through a slot f¹ into the end of the goose-neck to form such
connection, and is loosened when the mandrel head requires adjustment. An arm F
is fitted movably upon the goose-neck, and is projected toward the mandrel A¹ and
provided at its lower end with an outboard bearing for the mandrel.
The socket which retains the mandrel upon the end of the arm is provided with
a cap Bl secured by removable bolts b³, and the sleeve G is provided with a socket
or chuck B having a similar cap, so that the mandrel may be removed laterally
from its bearings. A bushing 132 adapts the socket to receive and fit mandrels
of different sizes. The arm F³ is clamped adjustably upon the goose-neck by
screws and is thus adapted to support a mandrel of any length, while the bolt f
adapts the brace F to hold the goose-neck at any height.
An aperture O' is formed in the cutter head with bearings N2 at its opposite
sides to sustain the cutter spindle, which is formed in two sections N¹ and n¹.
The sections are connected by a threaded joint formed of a socket o³ upon the
section N' and a threaded stud o³ upon the section n¹. The end of the section N¹
extends only part way across the aperture 0%, to permit the removal of the
cutter between the end of such section and the outer bearing N³. The sections
are formed with shoulders z. z¹ to clamp the cutter when the stud is screwed into
the socket 0%.
The outer section of the spindle, lettered n', is formed upon its outer end to
fit a wrench which may be applied thereto for rotating such section and screwing
the stud o into the socket o; when clamping the cutter upon the spindle. When
it is desired to remove the cutter, the wrench is used to unscrew the stud from the
socket by rotating the section n', and when the two sections are thus detached, the
section n¹ may be wholly retracted from the aperture O', thus leaving space between
the outer bearing and the end of the sections N¹ to insert the cutter and slip it
upon the section N¹.
When the cutter is thus fitted upon the spindle, the
section is pushed inward and the stud o³ screwed into its socket, clamping the
cutter firmly between the shoulders z, z¹.
The section N is held in position in the bearing N, upon its outer side by the
gear wheel V, and upon its inner side by a collar forming the shoulder ".
By this construction the cutter spindle is firmly supported upon both sides of the
cutter, and the cutter may be removed from the spindle without removing the
section N¹ from its bearings. The section N¹ is connected upon the outer end by
change wheels and bevel gears D³ with the shaft L, one of the gears being fitted
to a spline D in the shaft.
To rotate the worm I' simultaneously with the cutter spindle N, a shaft P. is fixed

page_text: transversely upon the carriage D in
with the gears by cog-wheels v³.
circles only in Fig. 1.
suitable bearings, and connected at one end
The wheels and are indicated by dotted
A swivel bracket U is journalled to the outer end of the shaft P and provided
with bearings for bevel gears U. A spline shaft P¹ is fitted movably to one of
the bevel gears U¹, and is connected at the opposite end by a swivel bearing and
bevel gears U2 with one of the change wheels 1. Such connection is formed
by a shaft Us, upon which the locking device would operate when cutting spur
gears; but such locking device is not shown, as its operation is already well known,
and the drawing in Figs. 1 and 2 shows merely the connections required for hobbing;
with which the motion of gears would be continuous.
To this end a blank A to form a worm wheel, is shown upon the mandrel A', and
it is evident that the cutter O must rotate once for each tooth to be cut in the blank,
and that the worm I¹ must therefore rotate the worm wheel H and the mandrel A¹
in a proportional degree.
By means of the shafts P and P' the cutter is connected directly with the primary
change wheels I³, which may be adjusted to produce such proportional movement.
The secondary change wheels I perform an entirely new function in such a con-
nection, by affording the means to increase or diminish the effect of the ordinary
change wheels 13; as the change wheels I may be removed from their respective
shafts I and G³ and others of suitable size submitted at any time.
A means for raising and lowering the mandrel head F by power is shown in
Figs. 1 and 2. A screw Q is projected downward from the head beneath the
mandrel G, and is provided at the bottom with a rotary nut Q¹ journalled at the
bottom of the column and having a bevel wheel Q' attached thereto. A. shaft R is
inserted through one side of the column and provided at the outer end with means
to apply a wrench or crank. A shaft R' is projected through the opposite side of
the column, and provided at its outer end with a spur wheel R. Both shafts are
provided with bevel wheels R' fitted to the wheel Q³.
A frog V is fitted to turn upon the shaft R³ and limited in its movement by a
bolt n fitted to a slot n*.
A stud Vis fixed to the column and projected through the frog V, and provided
upon the outer end with a sleeve carrying a cog-wheel V' and a pulley V. The
pulley is omitted from Fig. 1.
The frog is furnished with two intermediates, adapted when one is used to
transmit the motion of the pulley V in one direction to the nut Q', and in the
opposite direction when both intermediates are used. The principal intermediate v³
is pivoted upon the frog between the wheels R³ and V2, and a wheel v¹ is pivoted
adjacent to the wheel in such position as to mesh therewith, and also with the
wheel V when the frog is shifted.
In Fig. 1 the principal intermediate is shown connecting the pulley with the
wheel R which, when the pulley is rotated to the right, as per arrow to in Fig. 1,
operates to turn the nut Q to the right and thus to raise the mandrel head F.
The frog is furnished with a handle V4, and when shifted thereby may be secured
by a nut upon the bolt n³. When moved into a reverse position to that shown in
Fig. 1, the intermediate would be disengaged from the wheel ², and the motion
would be transmitted through both the intermediates of and to the wheel R³, thus
reversing the motion as desired, and lowering the mandrel head F. The pulley V'
is connected by belt with a pulley J' upon the shaft J', and the mandrel head is
raised or lowered by placing the frog in the desired position to move the head
upward or downward. When the head is moved approximately to the desired
position, the frog is shifted to an intermediate position, in which neither of the wheels
would engage the wheel V, and the pulley V' would therefore revolve without
affecting the nut. A thumb nut N is provided to clamp the frog in such inoperative
position.
The shaft R is then actuated by a crank or wrench to adjust the head accurately,
and
may also be used in feeding the blank toward the cutter.

page_text: The rotary nut b for the feed screw a is in like manner provided with a hand-
shaft connected with the nut by bevel wheels ct. The shaft is mounted in
a bearing adjacent to the nut bearing 61, and is arranged to shift longitudinally
to disengage the wheels c when the cutter head is actuated by the automatic
devices.
The shaft c is furnished with two grooves so, and a sliding key is fitted to a
slot in the bearing to engage either groove at pleasure, and to thus hold the shaft
in or out of gear with the wheel c.
It will be fully understood that the machine described herein is intended and
adapted for cutting spur gears as well as for hobbing worm wheels, in which case a
suitable spur cutter would be placed upon the arbor of the spindle R', and the
hobbing shaft P would be disconnected from such cutter spindle by removing one
of the gears . The shaft P is shown of sufficient length adjacent to the gear v²
to slide such gear outward, and thus disconnect the shaft without wholly removing
the gear.
A screws, which is shown in Fig. 2 in the hub of such gear, may be used to
hold it in its operative or inoperative position.
By the improvements above described, I greatly facilitate the use of the machine
for a wider range of work, and enable the operator to effect all the desired
adjustments with great rapidity.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, declare that what I
claim is :
1. In a gear cutter having a worm wheel, a worm and worm shaft to rotate the
blank, and primary change wheels to regulate the intermittent movement of the
blank, the combination, with the worm shaft, of an auxiliary shaft connected with
the said change wheels, and secondary change wheels connecting the auxiliary
shaft with the worm shaft, to vary the operation of the primary change wheels
upon the worm and the blank, substantially as herein set forth.
2. In a gear cutter, the combination, with a bed having a pan beneath the same,
of a movable cutter head with a cutter spindle revolved thereon, and the bed and
cutter head having coincident openings to discharge the chips to the pan.
3. In a gear cutter, the combination, with a cutter head having two spindle
bearings and a space between the same, of a cutter spindle with a cutter rotated in
such space, a jet pipe for projecting a cooling fluid upon the cutter, a pan formed
around the bottom of the bed, and an outlet to discharge the chips and fluid from
the space to such pan, substantially as herein set forth.
4. In a gear cutter, the combination, with a bed having a pan beneath the same,
of a movable cutter head with a cutter spindle revolved thereon, the bed and cutter
head having coincident openings to discharge the chips, a jet pipe for projecting a
cooling fluid upon the cutter, a sloping passage for conducting such chips and fluid
into the pan, with a lip above the bottom of the pan and a removable trough fitted
beneath such lip, the trough having a perforated false bottom and an outlet to
discharge the fluid, substantially as herein set forth.
5. In a gear cutting machine having a cutter head with aperture in the same to
admit the cutter, and spindle bearings N2 upon opposite sides of the aperture, the
combination, with the bearings N', of the spindle N¹ with arbor projected partly
across the aperture O¹, the spindle section n' movable in the bearing, and a threaded
connection between the sections, as and for the purpose set forth.
6. In a gear cutter having a horizontal bed with cutter head movable upon the
top of the same, and a column with mandrel bearing adjustable vertically thereon,
the means for rotating the cutter spindle in unison with the mandrel, consisting in
a worm wheel, a worm, and change wheels for rotating the same mounted adjustably
upon the column, a hobbing shaft supported in bearings transversely upon the
cutter head, gearing connecting the same at one end with the cutter spindle, and

page_text: gearing connecting the hobbing shaft with the worm through its change wheels, as
herein set forth.
7. In a gear cutting machine having a horizontal bed with cutter head movable
upon the top of the same, and a column with mandrel head adjustable vertically
thereon, the combination, with the mandrel and mandrel head, of an outboard
bearing fixed in line with the mandrel, and chucks with removable caps upon the
mandrel bearing and upon the outboard bearing to hold the mandrel reinovably,
substantially as set forth.
8. In a gear cutting machine having a bed with cutter head movable upon the
top of the same, and a column with mandrel and mandrel head adjustable vertically
thereon, the combination, with the cutter head, of a screw fixed thereto and
provided with a rotary nut, a cog-wheel upon the nut with suitable gearing to rotate
the same automatically, a laterally projecting shaft C and gears C connecting the
nut with the shaft, and means for turning the shaft by hand to adjust the screw and
cutter head, substantially as shown in Fig. 2.
9. In a gear cutting machine having a bed with cutter head movable upon the
top of the same, and a column with mandrel and mandrel head adjustable vertically
thereon, the combination, with the cutter head, of a screw fixed thereto, a rotary
nut mounted upon the outer end of the bed, a feed shaft with a train of gearing
connecting the shaft and nut by change wheels, and a separate train of gearing for
reversing the movement of the nut, a clutch to engage the separate trains
alternately with the nut, and the casing M enclosing such clutch and trains of
gearing, and having the bearings therefor cast upon such casing, substantially as
shown in Figs. and 4.
10. In a gear cutting machine having a bed with cutter head movable upon the
top of the same, and a column with mandrel bearing adjustable vertically thereon,
the combination, with the mandrel hearing, of a nut journalled in one end of the
column, a screw projected from the mandrel bearing through such nut, a bevel gear
with shaft projected laterally through the column, a spur wheel and frog upon the
outer end of such shaft, a stud with gear and pulley adjacent to such shaft, and
intermediate gears upon the frog adapted to transmit the motion of the pulley
reversely to the spur wheel, substantially as set forth.
11. A gear cutter having a bed with cutter head movable upon the top of the
same, a feed screw to actuate the cutter head, a column upon the bed with mandrel
head adjustable vertically thereon, with a worm wheel and worm carried by such
mandrel head to rotate the blank, a cutter spindle mounted upon the cutter head,
bearings fixed upon the bed or base of the machine, a driving shaft mounted in such
fixed bearings, with a driving pulley upon said shaft, and one or more trains of
gearing connecting such fixed pulley shaft with the movable cutter spindle, with
the feed screw, the worm, or other attachments.
12. A gear cutter having a bed with cutter head movable upon the top of the
same, a feed screw to actuate the cutter head, a column upon the bed with mandrel
head adjustable vertically thereon, with a worm wheel and worm carried by such
mandrel head to rotate the blank, a cutter spindle mounted upon the cutter head,
bearings fixed upon the bed or base of the machine, a driving shaft mounted in such
fixed bearings, with a driving pulley upon said shaft, a train of gearing actuated by
such pulley for rotating the worm, a separate train of gearing with change wheels
for rotating the cutter at a changeable rate of speed, and a separate train of gearing
with change wheels for feeding the cutter head at a changeable rate of speed, the
combination being adapted to actuate all the parts by means of a single driving
pulley supported upon the bed.
13. In a gear cutting machine having a horizontal bed A with a cutter head D
movable upon the top of the same, and a column E upon the inner end of the bed
with mandrel and mandrel head adjustable vertically thereon, the combination, with
the mandrel head, of a goose-neck projected therefrom, an arm secured adjustably
the goose-neck and provided with an outboard bearing for the mandrel, and a
upon

page_text: ¨vertical brace secured upon the outer end of the bed and having a slotted connection
to the end of the goose-neck, as herein set forth.
Dated this 10th day of November 1893.
J. C. CHAPMAN,
70, Chancery Lane, London, W.C., Associate Agent.