Improvements in Gear Cutting or Forming Machines.
Year: 1894

page_text: Date of Application, 17th Apr., 1894
Complete Specification Left, 20th July, 1894-Accepted, 6th Oct., 1894
PROVISIONAL SPECIFICATION.
Improvements in Gear Cutting or Forming Machines.
A communication by WILLIAM GLEASON and JAMES E. GLEASON, both of
Rochester, in the County of Monroe and State of New York, United States
of America, Machinists.
I, WILLIAM PHILLIPS THOMPSON, F.C.S., M.I.M.E., of The Agency for
Foreign Patent Solicitors, 6, Lord Street, Liverpool and 6 Bank Street,
Manchester both in the County of Lancaster and 323 High Holborn in the
County of Middlesex, Civil Engineer, do hereby declare the nature of this
invention to be as follows:-
This invention relates to that class of gear cutting or forming machines in which
the teeth of the gears to be cut are planed out and shaped or formed by means of
reciprocating tools so controlled as to move always in lines radial with a common
fixed point.
Medium or small sized gears are usually formed in these machines from solid
blanks by first rough-cutting away the metal to form the spaces between the teeth,
the latter being finally gone over with finishing tools to give their working faces
the proper incline and curvature.
The main object of the invention is to construct a complete automatic gear
planer by means of which when a blank is put into the machine to have teeth
formed upon it the machine being provided with the proper cutting tool and
properly adjusted and started will cut entirely around the blank without further
attention by the operator.
To accomplish this the following operations have to be performed in succession
with each tool employed, viz.: (1) the reciprocating tool (the roughing tool for
instance) has to be fed against the work; (2) the feed thrown off when a space is
cut to a prearranged depth; (3) the tool (continuously reciprocating) moved back
clear from the blank; (4) the latter indexed and (5) the feed again thrown in.
All these general operations are repeated in the order named for each space or
groove cut in the face of the blank, the operator only needing to be present in time
to stop the machine after the spaces have been cut entirely around. The finishing
tools to give the proper form to the two faces of the teeth are afterwards
substituted successively for the roughing tool, the machine working automatically
in each case and going through the same succession and order of operations with
each of these tools as with the roughing tool. The attention of the operator
during the whole process of forming and completing the teeth of a gear is necessary
only to start and stop the machine each time around the blank and put in place
the proper tool for the work and make the necessary changes and adjustments of
the machine.
The invention further comprises numerous features of novelty relating to form,
combination and operation of the parts, the whole being hereinafter fully
described.
DESCRIPTION OF FIGURES.
L
J

page_text: Figure 4 is a side elevation of portions of the indexing mechanism seen as
indicated by arrows 4 in Figures 1 and 7, parts being broken away.
Figure 5 is a vertical transverse section of parts of the indexing mechanism
taken on the dotted lines 5 in Figures 1 and 7, parts being broken away and
omitted.
Figure 6 is a side view of the detent gear, showing the rigid stops, viewed the
same as Figure 5.
Figure 7 is an end view of the machine, seen as indicated by arrow 7 in Figure 1,
showing the general indexing mechanism, the friction pulley being diametrically
sectioned.
Figure 8 shows more clearly some of the essential parts of the indexing mechanism,
parts being vertically sectioned on a plane corresponding with the axis of the worm
or as upon the dotted line 88 in Figure 9.
Figure 9 is a face view of a part of the adjusting cylinder seen as indicated by
arrow 9 in Figure 8, parts being broken away and transversely sectioned as on the
dotted line at the point of said arrow 9.
Figure 10 is a side elevation of the graduated adjusting cylinder.
Figure 11 is a side elevation of parts at the left front of the machine, seen as
indicated by arrow 11 in Figure 1.
Figure 12 shows the essential parts of the detent for the indexing mechanism,
mainly vertically sectioned on the dotted line 12 12 in Figure 1, parts being shown
in two positions by full and dotted lines.
Figure 13 shows a transverse section on the dotted line 13 in Figure 4, of the
trip shaft.
Figure 14 is a plan of parts of the feed mechanism and the pull-back
mechanism.
Figure 15 is a vertical section of parts of the feed mechanism, along the axis of
the feed post, taken substantially on the dotted lines 15 15 in Figures 2 and 21,
parts being shown in two positions by full and dotted lines.
Figure 16 is a vertical cross section of the base block and associated parts at the
foot of the feed post, taken on the dotted line 16 16 in Figure 2.
Figures 17, 18 and 19, show in detail some of the co-acting parts of the relief
mechanism.
Figure 20 is a side view of parts at the upper end of the feed post, showing
some of the feed-relief mechanism, viewed as indicated by arrow 20 in
Figure 15.
Figure 21 is a view on top of the feed post, indicated by arrow 21 in Figure 15,
parts being omitted and broken away.
Figure 22 shows adjacent portions of the toothed rocker and the toothed ring in
engagement.
Figure 23 is a side elevation of parts at the front of the machine, seen as
indicated by arrow 23 in Figure 1, parts being omitted and other parts vertically
sectioned.
Figure 24 shows the head of the plug seen as indicated by arrow 24 in
Figure 26.
Figure 25 is a view of parts driving the feed, indicated by arrow 25¹ in
Figure 26, the gear being omitted and parts vertically sectioned on the dotted
line 25 25 in said latter figure.
Figure 26 is a horizontal section of a part of the turret, showing some of the
driving mechanism for the feed, taken on the dotted lines 26 in Figures 23
and 25.
Figure 27 is a side elevation of the pull-back mechanism, viewed as indicated by
arrow in Figure 14, parts being shown in two positions by full and dotted lines.
rigure 28 is a side view of parts of the trip mechanism, portions of the frame and
other parts being vertically sectioned along the axis of the trip shaft.
Figures 29, 30 and 31, show in detail the construction and operation of parts of

page_text: the trip mechanism, the last figure being a view indicated by arrow 31 in Figure 29,
various parts being shown in two positions by full and dotted lines.
Figure 32 is a side elevation of the adjustable connecting bar for the tool-
carrying slide with associated parts, seen as indicated by arrow 32 in Figure 1.
Figure 33 is a view of the connecting bar and associated parts, seen as indicated
by arrow in Figure 32.
Figure 34 is an elevation of the parts carrying the form holder, seen as indicated
by arrows 34 in Figures 1 and 36, parts being broken away and vertically sectioned
on the dotted line 34' in Figure 35.
Figure 35 is a part holding the form holder and some other parts, horizontally
sectioned on the dotted line 35 in Figure 34.
Figure 36 is a side elevation of the form-holding mechanism and adjacent parts
of the base block and tangent arm, seen as indicated by arrow in Figure 37, parts
being broken away and omitted and other parts vertically sectioned on various
planes.
Figure 37 is a plan of adjacent portions of the tangent arm and base block,
showing the form holder and form, seen as indicated by arrow 37 in Figure 36.
Figure 38 is a front elevation of the form holder, forms and form rider, seen as
indicated by arrow 38 in Figure 36.
Figure 39 is a rear view of the slide carrying the form holder.
Figure 40 is a plan of the buffer for the feed-relief lever, the spring barrel
being horizontally sectioned on the dotted line 40 in Figure 41.
Figure 41 is a side elevation of the buffer, seen as indicated by arrow 41 in
Figure 40.
Figure 42 is a front elevation of the buffer, parts of which and the supporting
grooved segment being transversely sectioned on the dotted line 42 in Figure 40.
Figure 43 is a front elevation of the tool-stock, tool holder and other parts,
seen as indicated by arrow 43 in Figure 1, parts being broken away and vertically
sectioned.
Figure 4 is an elevation of parts of the tool-stock, seen as indicated by
arrow 44 in Figure 43.
Figure 45 shows the tool holder and other parts horizontally sectioned on the
dotted line 45 in Figure 43.
Figure 46 shows the tilting head in plan, and the slide block horizontally
sectioned on the dotted line 46 in Figure 43.
Figure 47 is a plan of the bottom plate of the tilting head.
Figure 48 is a side elevation of the feed pawl and ratchet, with associated parts,
seen as indicated by arrows 48 in Figures and 11, parts being broken away and
the pawl shown in two positions by full and dotted lines.
Figure 49 shows a section of parts through the axis of the detent for the pawl,
on the dotted line 49 in Figure 48, indicated by arrow, the pawl being shown in
two positions by full and dotted lines.
Figure 50 shows the inner face of the pawl.
Figures 1 to 7 inclusive, 11, 14, and 23 to 27 inclusive, (which figures include
the general views,) are drawn to a scale of one-sixth working size; the remaining
figures, all detail, being drawn to various scales larger than the figures
enumerated.
GENERAL DESCRIPTION.
Referring to the parts shown, A is the frame of the machine, B the head-stock,
C the turret, and D the tangent arm. E is the blank gear to be cut, it being rigid
upon a horizontal spindle F, Figures 1 and 7, resting in the head-stock.
G, Figures 1, 4 and 7, is an indexing wheel with worin teeth of common
construction, rigid with the spindle F. H, Figures 1, 3, 11 and 23, is a horizontal
circular segment made rigid with the circular part of the frame. I, Figures 1, 2,
11, 16 and 23, is a shiftable base block for the feed mechanism, resting upon the
segment H.

page_text: "
The indexing mechanism is shown at K in the general Figures 1 and 7, and in
detail in Figures 4, 5, 6, 8, 12 and 13.
The feed mechanism is shown at L in the general Figures 1, 11 and 23, and in
detail in Figures 15 to 22 inclusive, and in Figures 40, 41, 42, and 48, 49, 50.
The trip mechanism, which releases the indexing mechanism and allows it to
operate, is shown at N in the general Figure 23, and in detail in Figures 3, 28,
29, 30 and 31.
The pull-back mechanism, for swinging the tangent arm and the cutting tool
back from the work after each operation in cutting a tooth is completed, is
shown at in the general Figures 1, 11 and 23, and in detail in Figures 14
and 27.
The form-holding mechanism, and the means for shifting the tangent arm, base
block and feed mechanism, are shown at P in the general Figures 1, 11 and 23,
and in detail in Figures 34 to 39 inclusive.
The mechanism for operating the tool and the feed mechanism, is shown at R
in the general Figures 1 and 23, and in detail in Figures 24, 25, 26, 32 and 33.
The tool-holding mechanism is shown at T in the general Figures 1 and 11, and
in detail in Figures 43 to 46 inclusive.
The frame of the machine is formed with a circular part at one end upon which
rests concentrically a flat semi-circular bed-piece S, Figures 1, 3, 11 and 23. This
forms a base upon which the turret C rests and upon which the latter is adapted
to swing in a horizontal plane around a vertical pivot a, Figure 11.
The axis of
this pivot and the axis of the gear-carrying spindle F are in a vertical plane.
The tangent arm D rests at one end in horizontal pivotal bearings in the upper
part of the turret in which it is adapted to swing through short distances in a
vertical plane upon a horizontal pintle b, the axes of this pintle and of the pivot a
being in a vertical plane. The tool-holding mechanism is secured to, and carried
by, a dovetail slide U, Figure 11, fitted to slide longitudinally in a corresponding
cavity in the tangent arm.
The pivot a, Figures 1 and 11, for the turret C is hollow, and within it rests
a concentric vertical shaft d, to the upper end of which is secured a spur pinion e
above the base of the turret, and to its lower end a bevel gear f. This gear is
engaged by a bevel driving pinion g secured to a horizontal driving shaft indicated
by dotted lines in Figure 1, to the outer end of which is secured an ordinary step
pulley V, Figures 1, 3 and 23.
THE TOOL-DRIVING MECHANISM.
Acting with the pinion e is an intermediate gear h, Figures 1 and 11, which turns
a third gear i, Figures 1, 23, 25 and 26, these three gears being in a horizontal
plane. Rigid with the gear i is a bevel pinion & adapted to turn a bevel gear 1,
Figures 1, 23, 25, 26 and 33, said pinion and gear, k and i, turning upon a vertical
stud m rigid in the plate of the turret.
The gear
is formed with a transverse slotted part n adapted to hold a shiftable
head by means of slides o o and stud p, Figures 1, 32 and 33. To the head + is
adjustably secured a bar W, Figures 1, 11, 32 and 33, which is connected at the
other end with the tool-carrying slide U, by means of a stud u rigid with the slide
upon which the connecting bar has a journal bearing. By means of this
construction the tool-holding mechanism and the tool are reciprocated by the
driving belt on the step pulley V.
and
In doing different kinds of work it frequently becomes convenient to alter the
length of the connecting bar, and for this purpose it is made longitudinally
adjustable in the head r. Referring to Figures 32 and 33 it will appear that the
bar rests in a channel or gain formed in the upper part of the head which is covered
by a plate s held to the head by clamping screws t, shown also in Figure 1. By
loosening these screws the connecting bar inay be shifted longitudinally in its
bearing in the head and so move the slide U nearer to or farther from the head r.

page_text: THE TOOL HOLDING AND CONTROLLING MECHANISM.
The slide U is formed with a central longitudinal T-shaped groove v, Figure 11,
and the slide block w of the tool-holding mechanism, Figures 1, 11, 43 and 46, has
a part extending into said groove, as shown. This slide block is held to place by
horizontal clamping bolts a passing through it and entering a sliding piece or
block yoccupying the wide portion of the groove c. Associated with the slide
block is a tilting head formed with a stem a' passing horizontally through the
slide block w and secured by a nut . This tilting head is formed with a vertical
circular opening cl, Figure 46, which is occupied by a stem d of the "tool-stock e',
Figures 11, 43, 44 and 45, said stem having a swivel motion in the tilting head.
By means of these constructions the point of the tool f1, Figures 1 and 11, may
be slightly tilted with reference to a horizontal, and slightly swung in a horizontal
plane, both of which motions are necessary in the successful planing of gear teeth.
The tilting head is formed with a recess g', clearly shown in Figures 43 and 46,
in which the tool-stock rests. The vertical side walls of this recess are each
formed with two faces meeting each other in an obtuse angle at the middle, but the
faces of the tool-stock opposing these respective walls are made straight. And as
the part of the tool-stock in the recess does not wholly fill the latter the swivel
motion of the tool-stock just mentioned is provided for. The slanting walls of the
tilting head form stops to limit the swivel motion of the tool-stock in both
directions.
The tilting head is held in its tilted positions by means of a horizontal bolt /',
Figures 11 and 43, rigid in said head and passing through curved slots in the
slide block w. These slots are concentric with the stem a' of the tilting head
and a nut is provided for holding the parts rigidly together when the bead is
tilted.
The tool-stock e serves to hold a longitudinally adjustable tool holder ',
Figures 1, 43, 44 and 45, formed with a horizontal rectangular cavity m¹, in which
the tool (1) is accurately fitted. This tool holder is made to slide horizontally
under a plate or gib y, Figures 1, 43, and 44, bolted to the tool-stock, and it is
provided with vertical and horizontal binding screws n' n', for holding the tool
rigidly in place. It is further formed with a shank o', Figures 44 and 45, extending
laterally through a rectangular cavity p¹ formed in the tool-stock, terminating in
a threaded part for receiving a binding nut ». The cavity is made longer
horizontally than the width of the shank to admit of a horizontal motion of the
tool holder for the purpose of adjusting the tool to the work. A traverse screw s¹,
Figures 43, 44 and 45, is threaded in the shank o¹ parallel with the cavity m³ by
means of which to longitudinally adjust the tool. The traverse screw has a simple
bearing in the tool-stock, back of a hollow screw-plug t¹, which admits of rotary,
but prevents longitudinal, motion for the traverse screw.
The stem d of the tool-stock extends downward through the tilting head z, as
appears in Figure 43; and to move the tool vertically we employ a headed shaft u¹,
Figures 11 and 43, threaded in a plate p¹ (shown in plan in Figure 47) secured
to the lower end of the tilting head by simple fastening screws, shown in dotted
lines in Figure 43. The axes of the shaft and the stem dare in line, and the
shaft is provided with a set nut w below vl to hold it firmly in place. The lower
end of the stem is counter-bored to receive the headed end of the shaft, and a
hollow follower is threaded into the stem to bear against and confine the head of
the shaft, as shown. The lower end of the follower is formed with a projecting
flange, and the plate is counter-bored on its inuer face to receive the flange, as
shown in Figure 43. By means of this construction the tool-stock, with the tool
holder and the tool, may be moved vertically by turning the shafi u' one way or
the other, while the tool-stock is permitted to turn freely in a horizontal direction
upon the head of the shaft u².
The shaft u is squared at its lower end to receive a wrench for turning it.

page_text: The slight swinging of the tool-stock horizontally in its bearing in the tilting
head is to cause the two cutting edges or points of the tool to be properly presented
successively to the work as the direction of motion of the tool is changed. For
this purpose the tool needs to be swung or shifted each time after a cut has been
taken across the face of the gear in either direction. To effect this successive
shifting of the tool a spring arm ', Figures 1 and 11, is made rigid with the tool-
stock so as to extend out across the arm D. The latter is formed with a longitudinal
T-shaped race a², in which are secured adjustable stop-studs 6, which are set in
positions to be encountered by the spring arm at each end of the stroke of the
tool, to turn the tool-stock in the tilting head, as stated.
The feed mechanism is operated by the following means: The shaft c', which is
horizontal, of the bevel gear 1, Figures 1, 23, 24, 25, 26, rests in a bearing in a
Parallel with the
horizontal cylindrical plug X fitted in a recess in the turret C.
shaft cand in the same horizontal plane is a second shaft also resting in the
plug, the two shafts being connected at one end by a gear e² and a pinion f two
to one in diameter. By this means the shaft c turns the shaft d. The plug is
formed with an overhanging flange through which bolts pass to secure the plug
rigidly to the turret. The outer face of the head of the plug is counter-bored, as
shown in Figures 23 and 24, in which to receive the gear and pinion f2 flush with
its surface. The shafts c and d terminate in equal overhanging threaded ends to
which is fitted an interchangeable grooved hub g'. This hub carries a shiftable
stud h, which operates a feed rod, Figures 1, 11, 23, 26 and 48, and it is usually
provided with a traverse screw to move the stud longitudinally within the hub.
This machine is calculated to have the tool cut either both ways across the face
of the gear or only in one direction, as may be required. If cutting both ways
the hub g' is put upon the quicker shaft d³ to feed twice to each revolution of the
driving gear for the tool. If cutting in one direction only the hub is put upon
chaft it to food only ongs to a vavulution of the rear /
The circular toothed segment H, Figures 1, 3, 11 and 23, is concentric with the
pivot a of the turret, and formed with circular T-shaped channels, Figures 1, 3
and 16. The base block I rests directly upon this segment and is secured thereto
by bolts m passing down into the grooves 1. Tongues n², Figures 15 and 16, of
the base block project into the grooves to hold the base block in place. By
loosening the bolts the base block with its superincumbent parts may be shifted
longitudinally upon the segment. The base block, which is sectoral in plan, is
formed with a circular T-shaped longitudinal race or cavity o³, Figures 2, 16
and 23, in its upper side, and upon the block a base plate Y rests, having a part
projecting into said race o. The base block is also provided with a circular
toothed rack, as shown, in the race o³, forming a part of the inner side wall of
the race.
A feed stand Z, Figures 11, 14, 15 and 23, is secured rigidly to the base plate Y
by clamping bolts p², and formed with a vertical central opening to receive a feed
post A. The feed post has a journal bearing in the stand, and it is formed with &
collar occupying a cavity s in the stand to support the post in place. Near its
lower end the feed post is provided with a rigid pinion u to engage the teeth of the
rack. The plate Y is formed with a vertical circular recess v², Figures 2, 15
and 16, in which to receive the pinion, and a smaller recess w³ to receive the lower
reduced end of the post and to form a journal bearing therefor.
A worm gear, Figures 1, 11, 15 and 23, is placed upon the post immediately

page_text: above the collar ³, adapted to turn independently of the post. A horizontal
tangent shaft, Figures 23 and 48, is held in bearings, Figure 1, rigid with the
stand Z upon which is secured a worm a³, Figures 1 and 15, to turn the gear ..
Rigid with the tangent shaft also a ratchet 63, Figures 1 and 48. This ratchet
is actuated by a pawl c³ held to turn upon a simple stud fixed in a paw!
carrier d³, Figures 1, 11 and 23, adapted to turn freely upon the shaft.
The feed rod, which passes near the pawl carrier, is provided with a shiftable
head held upon a stud frigid in the pawl carrier. The head turns upon the
stud as with a journal bearing; and by means of it and the feed rod, the feed-
actuating hub g³, Figure 23, is enabled to rock the pawl carrier and so turn the
ratchet and the shaft y'.
The pawl, shown in reverse position in Figure 50, is formed with two unequal
conical cavities g³ in which a pointed detent ³, Figure 49, is urged by a spring 3,
said detent and spring being held in a cavity in the adjacent part of the pawl
carrier. When the pawl is turned to engage the ratchet, as shown in full lines
in Figure 48, the detent enters the large cavity, and by pressing against its inclined
side holds the pawl against the ratchet. To throw the pawl out of action it is.
shifted by the attendant to the position indicated by dotted lines in Figures 48.
and 49 in which position the detent enters the small cavity and holds the pawl clear
from the ratchet.
The shaft y is provided with a rigid hand wheel ³ at its extreme outer end by
means of which the attendant, who stands at A' Figure 1, may turn the worm gear
independently of the actuating mechanism for said shaft.
Now it will be understood that if the connection between the worm gear and
feed post be such that the latter is turned by the former the base plate Y with the
feed mechanism and tangent arm will be moved upon the base block on account of
the pinion rolling along the toothed rack of the base block, the turret
swinging accordingly. That is to say, the action of the feed serves to swing the
turret and move the tool toward the work by sliding the base plate along its
bearing upon the fixed base block. The worm gear and the post are caused to.
coact or turn together at intervals by the following means:
The worm gear, usually made of composition, is formed with a series of fine
radial teeth o³, Figures 15 and 21, in its upper side, the teeth in practice being cut
in a ring of case-hardened iron, P, inserted rigidly in the gear.
Above the gear,.
upon the post, is a circular tilting ring or rocker m³, Figure 19, forined with teeth n³,
on a portion only of the rocker, to engage the teeth of the gear, as shown
in Figure 22. This rocker does not closely fit the post all round, but at two.
opposite sides its interior is made flaring, as shown in Figures 15 and 19. It is
held to the post by a transverse pin crossing the axis of the post at the middle
plane of the rocker, by means of which pin and the flaring interior the rocker is
permitted to tilt or rock vertically on the post, as indicated by dotted lines
in Figure 15. When the rocker is horizontal its teeth engage the teeth of the
worm gear and both must move together; but when in its tilted position the teeth
are disengaged and the rocker and the gear move independently of each other.
When the teeth of the two parts engage each other the feed is said to be
"thrown in " and the tool is urged against the work.
MEANS FOR THROWING OFF THE FEED.
This is
When the tool has cut to the proper depth into the blank in any given case the
feed has to be automatically thrown off to arrest the progress of the tool.
accomplished as follows:
The rocker is formed with a laterally extended part, in a vertical cavity in which
is inserted a lifter or tilter, Figures 15, 19 and 21, having its lower end in contact
with the worm gear, as shown. The axis of the lifter parallel with the axis of
the post, and the litter is urged downward against the gear by a spring s³, the
When the tool has cut to the proper depth into the blank in any given case the
feed has to be automatically thrown off to arrest the progress of the tool. This is
accomplished as follows:
The rocker is formed with a laterally extended part, in a vertical cavity in which
is inserted a lifter or tilter, Figures 15, 19 and 21, having its lower end in contact
with the worm gear, as shown. The axis of the lifter is parallel with the axis of
the post, and the litter is urged downward against the gear by a spring ³, the
action of which tends to tilt the rocker and throw the teeth out of engagement.

page_text: Above the rocker, upon the feed post, is a feed-relief lever t, Figures 15, 18, 20
and 21, fitted also to tilt as indicated by dotted lines in Figure 15, and free to move
horizontally upon the post. Above the lever, upon the post, is a hubbed plate v³,
Figures 11, 15, 17, 20 and 21, acting as a confiner for the lever and the rocker, the
plate being secured to the post by a set screw u³, Figure 1, so as to be shiftable
thereon. A sufficient space is left between the lever and the confiner to allow
the former room to tilt, as stated.
The feed-relief lever is provided at its upper side with a rigid longitudinal
tooth, Figures 15, 18 and 20, adapted normally to bear against the adjacent
surface of the confiner. The surface of the confiner above the tooth is plain save
as to a notch, Figure 17, into which the tooth may enter when, at any time, it
and said notch are presented to each other. Now when the tooth is out of the
notch and bears against the surface of the confiner, the lever is confined or held
down to a horizontal position and in turn presses the teeth of the rocker into the
teeth of the gear against the action of the spring. But when the lever and the
confiner are by any means brought relatively into positions in which the tooth
may enter the notch the spring immediately lifts the rocker and clears it from
the gear.
"
Above the confiner a cap y³ is screw-threaded into the upper end of the post; and
the confiner is provided with a hand lever 2³, Figures 1 and 23, by means of which
the attendant may move the tangent arm and the tool toward or from the work.
When the tooth enters the notch the feed instantly ceases, for the gear being
free to turn upon the post the latter is not affected by the continued action of the
feed-driving mechanism.
To control the feed-relief lever so as to cause the notch to be presented to the
tooth at the proper time to stop the feed, there is provided a horizontal circular
grooved segment a, Figures 1, 11, 23, 40, 41 and 42, concentric with the feed post,
over which the lever swings. To this segment are secured two stops, 64 and c,
which, arresting the horizontal motion of the lever in either direction, serve to
control the latter. When the tool is being fed against the work the lever is in
advance of the notch the parts moving relatively in the directions indicated by full-
line curved arrows in Figure 21. Now when the lever encounters the stop b*,
Figure 1, its motion will be arrested but the confiner will continue to move forward
and the tool continue to feed. When, however, the notch arrives at or overtakes
the tooth the lever will suddenly rise, from the action of the spring s³, releasing the
rocker and the worm gear, and the feed will instantly cease. That this action of
the parts will be quite sudden will be clearly understood by viewing Figure 20;
for when the tooth and the notch arrive at the relative positions there shown the
tooth will quickly slide into the notch and release the rocker, as stated.
Now, if after the feed has been thus terminated, the parts be by any means
turned to move in the opposite direction (indicated by dotted arrows in Figure 21)
the lever will encounter the other stop, c', and the tooth will be pushed out of
the notch.
This will again depress the rocker and throw the feed into action. When the
parts move in the directions indicated by dotted arrows in Figure 21, the
base plate and the feed mechanism, with the tangent arm will be moved back along
the base block on account of the action of the pinion u³ upon the toothed rack t²,
which will withdraw the tool from the work.
The stops & c are shiftable around the segment a', each being held to place
by ordinary clamping screws d' passing through them and threaded into nuts in
the groove of the segment, one of said nuts being shown at ein Figures 41 and 42.
By shifting or adjusting these stops the depth to which the tool will be fed into the
work in any given case may be accurately determined, and likewise the distance
the tool will be drawn back from the work.
It is preferable to make the stop c yielding by providing a horizontal bumper f4,
Figures 40, 41 and 42, for the lever to encounter, said bumper being actuated by a
spring g' back of it, as shown. The rear end of the bumper being threaded and

page_text: are so connected that while the arm may move vertically through short distances
independently of the feed mechanism, both the latter and the arm move together in
horizontal directions. The feed stand Z is formed with a horizontal rectangular
cavity, Figure 11, near the arm, in which is closely fitted a substantially cubical
block adapted to move laterally through short distances in a line parallel with
the arm.
To the rear vertical face of the arm and over the cavity it is rigidly
secured a bracket 1, Figures 1, 11 and 23, formed with a vertical downwardly-
projecting offset stem m', which passes into and through the block 4, fitting
accurately therein, but so as to move freely in a vertical direction. Now, as the
block can have no lateral motion in the cavity in a line toward or from the arm,
it follows that the latter and the feed mechanism must always move together in
horizontal directions, when the tool is moved toward or from the work, but that the
arm may move vertically independent of the feed mechanism.
THE PULL-BACK MECHANISM.
When the tool in any given case has been fed to the proper depth into the
blank and the feed thrown off the tool must be quickly withdrawn from the blank
and out of the way before the latter is indexed. The tool is withdrawn by sliding
the base plate back upon the base block, the arm moving with it, which is
effected as follows:
B is a holding arm, Figures 11, 14, 23 and 27, made rigid with the base block,
to which is pivoted a bent lever C', adapted to swing in a vertical plane. The
short arm of this lever is joined to the tangent arm D or to some convenient part
of the mechanism supported by the base block as, for instance, to a clamping
bolt p³, by a connecting bar n', as shown, the joint at either end of the bar being
free to move.
The long end of the lever is adapted to hold a shiftable weight D₁,
which when unopposed serves to keep the tangent arm swung back from the work.
When the tangent arm is moved toward the work by the feed mechanism it is done
against the action of the weight. For instance, referring to Figure 27, when the
tool is commencing to act upon the blank the lever C₁ and associated parts occupy
the positions shown in full lines; but while the tool is being fed to its extreme
depth into the work the lever and associated parts are gradually moved to the
positions shown by dotted lines. Now the instant the toothed rocker of the feed
mechanism is tilted to release it from the worm gear the lever C¹ will be returned
to the position shown by full lines in the figure in which the cutting tool is drawn
clear from the blank.
To prevent the weight pulling the parts back with too violent action when the
feed is thrown off, a vertical dash pot E' is employed rigid with the supporting
arm B', provided with a plunger F connected with the lever, shown in longitudinal
section in Figure 23. At the bottom of the dash pot is a pet cock o' through which
air is supplied to the space below the plunger. The opening through the pet cock
being small the escape of air as the plunger descends must be gradual, on account
of which the plunger will be cushioned upon the air beneath it and relieve the
shock of the descending weight. By regulating the opening through the pet cock
the cushioning of the plunger may be controlled.
After the tooth of the feed-relief lever enters the notch in the confiner by the
lever meeting the stop b, as stated, the lever and the confiner remain engaged and
move together when thrown back toward the yielding buffer by the pull-back
mechanism. The device is so arranged that the weight throws the parts back
sufficiently to cause the lever to sharply encounter the yielding buffer, the effect of
which is to throw the tooth out of the notch and depress the lever and the rocker,
which again throws the feed into action.

page_text: The contiguous faces of the notch and the tooth are inclined at an angle of
about 450 which permits the tooth to slide easily out of the notch.
The operation of the feed mechanism and the pull-back mechanism is such that
the former gradually moves the base plate Y, with its superincumbent parts
including the tangent arm, through a given distance in one direction, and the latter
moves the same parts suddenly in the opposite direction through the same
distance.
After the tangent arm is thrown back by the pull-back mechanism and the
tool cleared from the blank the latter is indexed, which is done by the following
means:
G¹, Figure 8, is a tangent shaft for the worm gear G, Figures 1, 4 and 7, which
carries a worm H' to engage the gear. I is a horizontal hanger bolted rigidly to
the head stock B, and the tangent shaft rests in bearings pp therein. The
shaft is formed with an enlarged overhanging part constituting a collar which
bearing against the contiguous bearing p* prevents end travel of the shaft in one
direction, while set nuts turned against the bearing on the opposite side, prevent
end travel of the shaft in the other direction. K' is a short extension shaft for G',
which on account of the connecting parts, is practically in one piece with said
shaft G. To the shaft K', is secured a removable toothed pinions which is a
part of a system of gearing for turning G'. A shaft t is held parallel with the
shaft G', in an extended part of the hanger I', and provided at one end with a
removable overhanging gear u, which by means of a changeable compound inter-
mediate vis adapted to turn the pinion stand the shaft G¹ This train of
gearing, with the means for holding and operating the compound intermediate, is
common to lathes and similar machinery.
At the other end of the shaft t is secured.a. gear L' which is turned indirectly
by means of a pinion w, Figures 1 and 5, held upon the shaft N¹ resting in
horizontal bearings in the hanger l'. The position of the shaft N' is such that its
axis is in line with the axis of the tangent shaft G'. The pinion to and gear L'
are connected by means of intermediate pinions y held by a shiftable frog at,
Figures 1, and 7. This frog, which is of common construction and operation, is
adapted to turn upon the shaft N¹ and to be set in either of two positions so as to
bring one or the other of the intermediate pinions y into mesh with the gear L' for
the purpose of controlling the direction of motion of the tangent shaft G₁.
The shaft N' and the whole indexing mechanism is driven by a belt on the
friction pulley O¹, which is constructed as follows: The web of the pulley O',
Figure 7, is a thin plate formed with a hub adapted to turn freely upon the shaft N¹.
This web is inclosed by two circular disks and a, as shown, the former disk
being rigid with the shaft N' and the latter disk turning with the shaft but being
adapted to move longitudinally thereon. The disk a' is formed with an extended
hub formed with a cavity in which is placed, upon the shaft, a spiral spring b
confined by a nut threaded upon the shaft and adapted to enter the cavity in the
hub. The web of the pulley and the contiguous faces of the disks are forned with
annular depressions opposing each other in which are placed rings d' of friction
material, as leather. The disks are not in contact with the web of the pulley but
a little apart therefrom, the connection between said disks and the web being
through the medium of the friction rings. The tendency of the spring 6 is to
press the disk a³ toward the web of the pulley and the latter toward the rigid
disk and by turning the nut c one way or the other to regulate the tension of
the spring the friction at the leather rings may be controlled.
The tensity of the friction is maintained at all times sufficient to enable the
continuously rotating pulley O' to turn the whole indexing mechanism, from which
it will be understood that, unopposed, the belt on said pulley would keep the blank

page_text: gear continually revolving. To hold the latter while a tooth is being cut a detent
for the indexing mechanism is interposed, the same being as follows:
A
The gear L is provided upon its inner side with rigid lugs or stops e es,
Figures 6 and 12, opposing each other and near the periphery of the gear.
horizontal detent bolt f, appearing in Figures 1 and 5, but better shown in
Figure 12, is adapted to have its free end enter between the stops e es, as shown,
to prevent the rotation of the gear. The bolt is held by a barrel rigid in the
hanger I, within which is a spiral spring upon the bolt, pressing against the
collar of the latter in a manner to force it against the gear. Thus normally
the action of the indexing mechanism will be arrested.
To temporarily withdraw the detent bolt to release the mechanism for the
purpose of indexing the blank there is employed a horizontal longitudinal trip
shaft, Figures 1, 4, 7, 13 and 28, resting in bearings in the frame beneath the
head-stock. To the overhanging end of the barrel 9, over the trip shaft, is
rigidly secured a downwardly-extending arm k, Figures 7 and 12, provided at its
lower end with a lengthened longitudinal hub, through the axis of which the trip
shaft passes, as appears in Figures 1, 4 and 13. The shaft turns freely in the hub,
the latter forming a sort of pendant bearing for the shaft. The pendant arm k is
bifurcated at its lower end, including the hub, in the space between the branches of
which is inserted the hub of a smaller detent-releasing arm provided with a
spline m, Figure 13, which rests in a longitudinal groove n in the trip shaft,
Figure 1. By means of the groove and the spline, the shaft and the releasing arm
move together as to rotatory motions of the former, but the arm may freely slide
longitudinally along the shaft independently of the latter. The detent bolt fo
projects to some distance beyond the outer end of the barrel, and the releasing arm
takes hold of this projecting part, as shown in Figures 5 and 12. Upon each side
of the releasing arm, upon the detent bolt, is placed a collar o rigid with the bolt,
between which collars the arm may freely move but without lost motion. Now a
slight turning of the trip shaft toward the right, (as appears in Figures 7 and 13,)
will throw the releasing arm and the detent bolt to the positions shown by dotted
lines in Figure 12. In this position the bolt is withdrawn from between the
stops of the gear L', which serves to temporarily release the latter and the whole
indexing mechanism, and allow the latter to act until the gear makes a complete
revolution and is again caught by the detent bolt.
THE TRIP MECHANISM.
The bed piece S, Figures 1, 3, 23 and 28, is formed with a circumferential
groove in which is fitted to slide a circular segment P¹ to which the turret C is
rigidly bolted so that both parts, P¹ and C, move together. This segment is
formed with a horizontal peripheral dovetail grooves for holding bolts to adapted
to rigidly secure in place a downwardly-extending shiftable trip arm us, as shown.
The trip shaft projects beyond the bearing, to the overhanging end of which is
rigidly secured a crank arm, see also Figures 29, 30 and 31.
The crank arm is
provided with a pendant latch was held in a cavity therein and adapted to swing on
a pivot screw a rigid in the crank arm. The latch is free to move toward the
left, (as appears in Figures 3, 29 and 30,) but encounters a shoulder y of the
crank arm when pushed toward the right. The trip arm u has its lower end
turned inward at right-angles, as shown in Figure 28, in position to engage the
extreme point of the latch when the turret is turned toward the right, as appears
in Figure 3.
The trip arm, when the pull-back mechanism turns the turiet backward or
toward the right, comes in contact with the latch, as indicated in Figure 29,
and turns the trip shaft through a small distance or until the parts assume the
positions indicated by dotted lines in Figures 29 and 12. This turning of the
shaft, it will be understood, is against the action of the spring of the detent
bolt, Figure 12; and when the parts are in the positions shown by dotted lines

page_text: in Figure 29 the latch has swung high enough to clear the contiguous edge of
the trip arm. When these relative positions of the parts are reached the
spring will immediately cause the parts connected with the trip shaft at both
ends to assume their normal positions, shown in full lines.
The dotted positions of the parts shown in Figure 29 correspond with the
dotted positions of the parts shown in Figure 12; and likewise the full-line
positions of the parts in the two figures correspond; that is to say, when the trip
arm moves the crank arm to the position shown by dotted lines in Figure 29 the
detent bolt will be withdrawn from the stops on the gear L', serving to release
the latter and set the indexing mechanism in motion.
The turning of the arm by the arm u through the short distance indicated
is but the work of a moment but sufficiently long to release the gear L' and
allow it to turn. When the latch w clears u', as stated, the spring will
immediately drive the detent bolt forward against the gear, but the stop e* having
then passed on, on account of the rotation of the gear, the latter will make a
complete revolution before being again arrested by the bolt. During this turning
of the gear the bolt simply slides around against its smooth surface until the
inclined end of the approaching stop is encountered, when the bolt rides up the
same and springs back into the space between the stops. This again stops the gear
and holds the indexing mechanism from acting.
The motions of the parts are so timed that the indexing mechanism is not
tripped or started until the tool has been drawn back clear of the blank. And
the indexing is done while the tool is being again fed toward the blank but before
it reaches the latter.
When the latch has cleared the trip arm, as stated, and the arm & has returned
to its normal position, the trip arm will be a short distance to the right of the
latch as will appear by viewing Figure 29. Now as the feed again slowly turns
the turret the trip arm will be gradually moved toward the left and again encounter
the latch, as in a backward stroke. But the latch being free to move in that
direction the crank arm and the trip shaft are not affected by the trip arm, the
latch simply swinging out of the way as the trip arm passes. When the latter, in
moving toward the left, reaches the position shown in Figure 30, it will clear the
latch, which then assumes its normal position by gravity ready to be encountered
again by the trip arm.
Two corresponding opposing stops are employed on the gear L' so that the
indexing mechanism will work if turned in either direction.
MEANS FOR ADJUSTING THE WORK.
It frequently becomes necessary when using the finishing tools to adjust the
work to the tool by turning the blank slightly in one direction or the other without
disturbing the indexing mechanism. To provide for this adjustment there is
employed an adjusting cylinder R¹, Figures 1, 4, 7, 8 and 9, interposed somewhere
in the indexing mechanism between the shafts N' and G', preferably upon the latter
or upon the shaft t. As shown, this cylinder consists of a main part 2 and a
corresponding minor part a°. The part is made rigid with the shaft G' and
formed with an annular T-shaped groove & in its face to receive clamping bolts,
as shown, the bolts being inserted through a square opening d in the back of the
piece. The bolts bold the part a rigid with the part 2, and the extreme reduced
end of the shaft G enters a short distance to centre the latter. The short
shaft K' is rigid in a so that when the bolts are tightened the shaft K' is practically
& continuation of the shaft G', both parts turning together.
The periphery of the part 2 adjacent to a is divided into a scale of equal parts,
as appears in Figures 1, 7 and 10, forty divisions, more or less, as may be found
convenient, being employed. A single corresponding mark is formed on the adjacent
part of a as an indicator for the relative positions of the two parts. Now as the
part is rigid with the shaft Gl then by loosening the bolts & coid shatt man ha

page_text: turned independently of the part a and all the gearing between it and the shaft N¹.
By this means the work may be brought exactly to the tool by turning it as may
be required. After the adjustment is made the bolts are again tightened.
THE FORM MECHANISM.
In planing gears in this machine the faces of the teeth are copied from forms as
in other machines of this class. The extreme lower corner of the tangent arm is
provided with a rigid but removable form rider e, Figures 11, 23, 37, 36 and 38.
The form rider inclines downward and backward in position to bear upon an
inclined form S', as shown. The form used for rough-cutting the teeth is straight
and horizontal, as shown. For finishing the faces of the teeth curved forms T¹ T
are employed. These forms are held in a form holder U¹ secured indirectly to the
base block I of the feed mechanism. A vertical grooved body V' is secured rigidly
to the base block by a screw f', in which body is fitted a slide W₁ adapted to move
vertically. The slide is formed with a projecting inclined part X' against which
the form holder is held upon a stud 9 rigid in the slide. A clamping nut /*
secures the form holder rigidly in place, and by loosening which the holder may be
turned to bring either form into action as may be required. A detent of some
simple kind is employed to accurately set the form holder in each of its positions
of adjustment.
For vertically adjusting the forms a lifting screw i, Figures 34 and 35, is
employed threaded in a bearing in the part V₁ in position to bear upward against
a part of the slide. This lifting screw is provided with a set nut to hold it in
place after adjusting the form. The body V₁ overhangs and partly covers the
teeth of the segment H and it is provided with a pinion Y upon a vertical
shaft m turning in bearings in V1, Figures 11, 23, 34, 36 and 37, the pinion being
in position to engage the teeth 1. The shaft m' is squared at to receive a wrench
for turning it for the purpose of moving the base block around upon the segment,
the holding bolts m' being first loosened. Wheu thus shifting the base block, the
feed mechanism, the tangent arm, the pull-back mechanism, and the form-holding
mechanism go with it, all these parts being secured to or carried by the base block.
The shifting of the base block with its dependent parts is for the purpose of
adapting the machine for planing gears of different diaineters and bevels.
The head-stock B is adapted to be moved longitudinally upon the frame by a
horizontal traverse screw Zi, Figures 1 and 7, beneath it. This screw rests in a
bearing of rigid with the frame and operated by an overhanging crank p..
As the machine is constructed, the indexing mechanism is at one end, and the
trip mechanism at the other end, of the frame.
Dated thie 16th day of April 1894.
COMPLETE SPECIFICATION.
Improvements in Gear Cutting or Forming Machines.
A communication by WILLIAM GLEASON and JAMES E. GLEASON, both of
Rochester, in the County of Monroe and State of New York, United States
of America, Machinists."
1, WILLIAM PHILLIPS THOMPSON F.C.S., M.I.M.E., of The Agency for
Foreign Patent Solicitors, 6 Lord Street, Liverpool and 6, Bank Street, Manchester,
both in the County of Lancaster and 323 High Holborn in the County of Middlesex,
Civil Engineer, do hereby declare the nature of this invention and in what manner

page_text: the same is to be performed, to be particularly described and ascertained in and
by the following statement:-
This invention relates to that class of gear cutting or forming machines in which
the teeth of the gears to be cut are planed out and shaped or formed by means of
reciprocating tools so controlled as to move always in lines radial with a common
fixed point.
Medium or small sized gears are usually formed in these machines from solid
blanks by first rough-cutting away the metal to form the space between the teeth,
the latter being finally gone over with finishing tools to give their working faces the
proper incline and curvature.
The main object of the invention is to construct a complete automatic gear
planer by means of which, when a blank is put into the machine to have teeth
formed upon it, the machine being provided with the proper cutting tool and
properly adjusted and started, will cut entirely around the blank without further
attention by the operator.
To accomplish this, the following operations have to be performed in succession
with each tool employed, namely:-(1) the reciprocating tool (the roughing tool,
for instance,) has to be fed against the work; (2) the feed thrown off when a space
is cut to a prearranged depth; (3) the tool (continuously reciprocating) moved
back clear from the blank; (4) the latter indexed and (5) the feed again thrown
in. All these general operations are repeated in the order named for each space or
groove cut in the face of the blank, the operator only needing to be present in time
to stop the machine after the spaces have been cut entirely around. The finishing
tools to give the proper form to the two faces of the teeth are afterwards
substituted successively for the roughing tool, the machine working automatically
in each case and going through the same succession and order of operations with
each of the tools as with the roughing tool. The attention of the operator during
the whole process of forming and completing the teeth of a gear is necessary only
to start and stop the machine each time around the blank and put in place the
proper tool for the work and make the necessary changes and adjustments of the
machine.
The invention further comprises numerous features of novelty relating to form,
combination and operation of the parts, the whole being hereinafter fully described
and more particularly pointed out in the claims.
Referring to the drawings filed wih the Provisional Specification:
Figure 1 is a general plan of the gear planer, parts being broken away and
omitted..
Figure 2 is a plan of parts at the base of the feed mechanism.
Figure 3 is a front end view of the frame and other parts, seen as indicated by
arrow 3 in Figure 1, better showing the trip mechanism.
Figure 4 is a side elevation of portions of the indexing mechanism, seen as
indicated by arrow 4 in Figures 1 and 7, parts being broken away.
Figure 5 is a vertical transverse section of parts of the indexing mechanism
taken on the dotted line 5 in Figures 1 and 7, parts being broken away and
omitted.
Figure 6 is a side view of the detent gear, showing the rigid stops, viewed the
same as Figure 5.
Figure 7 is an end view of the machine seen as indicated by arrow 7 in Figure 1,
showing the general indexing mechanism, the friction pulley being diametrically
sectioned.
Figure 8 shows more clearly some of the essential parts of the indexing mechanism,
parts being vertically sectioned on a plane corresponding with the axis of the worm,
or as upon the dotted line 88 in Figure 9.
Figure 9 is a face view of a part of the adjusting cylinder, seen as indicated by
arrow 9 in Figure 8, parts being broken away and transversely sectioned as on the
dotted live at the point of said arrow 9.

page_text: Figure 1 is a side elevation of the graduated adjusting cylinder of the indexing
mechanism.
- Figure 11 is a side elevation of parts at the front of the machine, seen as indicated
by arrow 11 in Figure 1.
Figure 12 shows the essential parts of the detent for the indexing mechanism,
mainly vertically sectioned as on the dotted line 12 12 in Figure 1, parts being
shown in two positions by full and dotted lines.
Figure 13 shows a transverse section on the dotted line 13 in Figure 4, of the trip
shaft and portions of the associated parts.
Figure 14 is a plan of parts of the feed and the pull-back mechanism.
Figure 15 is a vertical section of parts of the feed mechanism along the axis of
the feed post, taken substantially on the dotted lines 15, 15, in Figures 2 and 21,
parts being shown in two positions by full and dotted lines.
Figure 16 is a vertical cross section of the base block and associated parts at the
foot of the feed post taken as on the dotted line 16 16 in Figure 2.
Figures 17, 18 and 19 show in detail some of the co-acting parts of the relief
mechanism.
Figure 20 is a side elevation of parts at the upper end of the feed post,
showing some of the feed relief mechanism viewed as indicated by arrow 20 in
Figure 15.
Figure 21 is a view on top of the feed post indicated by arrow 21 in Figure 15,
parts being omitted and broken away.
Figure 22 shows adjacent portions of the toothed rocker and the toothed ring in
engagement.
Figure 23 is a side elevation of parts at the front of the machine, seen as indicated
by arrow 23 in Figure 1, parts being omitted.
Figure 24 shows the head of the plug, seen as indicated by arrow 24 in
Figure 26.
Figure 25 is a view of parts driving the feed, indicated by arrow 25¹ in
Figure 26, parts being omitted and other parts being vertically sectioned on the
dotted line 25 25 in said latter figure.
Figure 26 is a horizontal section of a part of the turret, showing some of
the driving mechanism for the feed, taken on the dotted lines 26 in Figures 23
and 25.
Figure 27 is a side elevation of the pull-back mechanism, viewed as indicated
by arrow in Figure 14 Sheet 3, parts being shown in two positions by full and
dotted lines,
Figure 28 is a side view of parts of the trip mechanism, portions being vertically
sectioned along the axis of the trip shaft.
Figures 29-31 show in detail the construction and operation of parts of the trip.
mechanism, the last figure being a view indicated by arrow 31 in Figure 29.
Figure 32 is a side elevation of the adjustable connecting bar for the tool-.
carrying slide with associated parts, seen as indicated by arrow 32 in Figure 1.
Figure 33 is a view of the connecting bar and associated parts, seen as indicated
by arrow in Figure 32.
Figure 34 is an elevation of the parts carrying the form-holder, seen as indicated
by arrow 34 in Figure 36, parts being broken away and vertically sectioned as on
the dotted line 34' in Figure 35.
Figure 35 is a part holding the form-holder, and some other parts, horizontally
sectioned as on the dotted line 35 in Figure 34.
Figure 36 is a side elevation of parts under the end of the tangent arm, seen as
indicated by arrow in Figure 37, parts being broken away and omitted and other
parts vertically sectioned on various planes.
Figure 37 is a plan of parts under the extreme end of the tangent arm, showing
the form-holder, and associated parts.
Figure 38 is a front elevation of the. form-holder, forms and form rider, seen as
indicated by arrow 38 in Figure 36.

page_text: rests concentrically a flat semi-circular bed-piece S, Figures 1, 3, 11 and 23. This
forms a base upon which the turret C rests and upon which the latter is adapted to
swing in a horizontal plane around a vertical pivot a, Figure 11. The axis of this
pivot and the axis of the gear-carrying spindle F are in a vertical plane.
The tangent arm D rests at one end in horizontal pivotal bearings in the upper
part of the turret in which it is adapted to swing through short distances in a
vertical plane upon a horizontal pintle b, Figures 1 & 23, the axes of this pintle
and of the pivot a being in a vertical plane.
The tool-holding mechanism is secured to and carried by a dove-tail slide U,
Figure 11, fitted to slide longitudinally in a corresponding cavity in the
tangent arm.
The pivot a, Figures 1 and 11, for the turret C is hollow, and within it rests a
concentric vertical shaft d, to the upper end of which is secured a spur pinion e
above the base of the turret and to its lower end a bevel gear f. This gear is
engaged by a bevel driving pinion g, secured to a horizontal driving shaft indicated
by dotted lines in Figure 1, to the outer end of which is secured an ordinary step
11
Ty
1
Acting with the pinion e is an intermediate gear h, Figures 1 and 11, which turns
a third gear i, Figures 1, 23, 25 and 26, these three gears being in a horizontal
plane. Rigid with the gear i is a bevel pinion k adapted to turn a bevel gear 1,
Figures 1, 23, 25, 26 and 33, said pinion and gear k and i turning upon a vertical
stud m, rigid in the plate of the turret.
l
The gear is formed with a transverse slotted part n, adapted to hold a shiftable
head r by means of slides o o and stud p, Figures 1, 32 and 33. To the head r is
adjustably secured a bar W, Figures 1, 11, 32 and 33, which is connected at the
other end with the tool-carrying slide U, by means of a stud u rigid with the slide,
and upon which the connecting bar has a journal bearing. By means of this
construction, the tool-holding mechanism and the tool are reciprocated by the
driving belt on the step pulley V.
In doing different kinds of work, it frequently becomes convenient to alter the
length of the connecting bar, and for this purpose it is made longitudinally
adjustable in the head r. Referring to Figures 32 and 33, it will appear that
the bar rests in a channel or gain formed in the upper part of the head, which is
covered by a plate s held to the head by clamping screws t, shown also in Figure 1.
By loosening these screws, the connecting bar may be shifted longitudinally in
its bearing in the head and so move the slide U nearer to or farther from the
head r.
THE TOOL-HOLDING AND CONTROLLING MECHANISM.
The slide U is formed with a central longitudinal T-shape groove v, Figure 11,
and the slide block w of the tool-holding mechanism, Figures 1, 11, 43 and 46,
has a part extending into said groove, as shown. This slide block is held to place
by horizontal clamping bolts passing through it and entering a sliding piece or
block y occupying the wide portion of the groove v. Associated with the slide
block is a tilting head z formed with a stem a' passing horizontally through the
slide block w and secured by a nut b. This tilting head is formed with a vertical
circular opening c', Figure 46, which is occupied by a stein d' of the tool-stock e',
Figures 11, 43, 44 and 45, said stem having a swivel motion in the tilting bead.
By means of these constructions, the point of the tool f', Figures 1 and 11, may
be slightly tilted with reference to a horizontal and slightly swung in a horizontal
plane, both of which motions are necessary in the successful planing of gear
teeth.
The tilting head is formed with a recess g', clearly shown in Figures 43 and 46,
C

page_text: in which the tool-stock rests. The vertical side walls of this recess are each.
formed with two faces meeting each other in an obtuse angle at the middle, but
the faces of the tool-stock opposing these respective walls are made straight. And,
as the part of the tool-stock in the recess does not wholly fill the latter, the swivel
motion of the tool-stock just mentioned is provided for. The slanting walls of the
tilting head form stops to limit the swivel motion of the tool-stock in both
directions.
The tilting-head is held in its tilted positions by means of a horizontal bolt A',
Figures 11 and 43, rigid in said head and passing through curved slots in the
slide block w0. These slots are concentric with the stem a of the tilting head, and
a nut is provided for holding the parts rigidly together when the head is tilted.
The tool-stock e' serves to hold a longitudinally adjustable tool-holder,
Figures 1, 43, 44 and 45, formed with a horizontal rectangular cavity m', in which
the tool is accurately fitted. This tool-holder is made to slide horizontally under
a plate or gib y, Figures 1, 43 and 44, bolted to the tool-stock, and it is provided
with vertical and horizontal binding screws n'n', for holding the tool rigidly
in place. It is further formed with a shank o', Figures 44 and 45, extending
laterally through a rectangular cavity p' formed in the tool-stock terminating in a
threaded part for receiving a binding nut. The cavity is made longer horizontally
than the width of the shank to admit of a horizontal motion of the tool-holder for
the purpose of adjusting the tool to the work. A traverse screws', Figures 43, 44
and 45, is threaded in the shank o', parallel with the cavity m¹ by means of which
to longitudinally adjust the tool. The traverse screw has a simple bearing in the
tool-stock back of a hollow screw-plug t which admits of rotary, but prevents
longitudinal, motion for the traverse screw.
The stem d' of the tool-stock extends downward through the tilting head z, as
appears in Figure 43; and to move the tool vertically, a headed_shaft u',
Figures 11 and 43, is employed, threaded in a plate v (shown in plan in Figure 47)
secured to the lower end of the tilting head by simple fastening screws shown in
dotted lines in Figure 43. The axis of the shaft and the stem d' are in line, and
the shaft is provided with a set nut w¹ below v' to hold it firmly in place. The
lower end of the stem is counter bored to receive the headed end of the shaft, and
a hollow follower a' is threaded into the stem, to bear against and confine the head
of the shaft, as shown. The lower end of the follower is formed with a projecting
flange, and the plate v is counterbored on its inner face to receive the flange, as
shown in Figure 43. By means of this construction, the tool-stock, with the
tool-holder and the tool, may be moved vertically by turning shaft u' one way or
the other while the tool-stock is permitted to turn freely in a horizontal direction
upon the head of the shaft u¹.
The shaft u' is squared at its lower end to receive a wrench for turning it.
The slight swinging of the tool-stock horizontally in its bearing in the tilting
head is to cause the two cutting edges or points of the tool to be properly
presented successively to the work as the direction of motion of the tool is
changed. For this purpose, the tool needs to be swung or shifted each time after
a cut has been taken across the face of the gear in either direction. To effect
this successive shitting of the tool, a spring arm 2', Figures 1 and 11, is made rigid
with the tool stock so as to extend out across the arm D. The latter is formed
with a longitudinal T-shaped race a', in which are secured adjustable stop-studs 6*
which are set in positions to be encountered by the spring arm at each end of the
stroke of the tool to turn the tool-stock in the tilting head; as stated.
THE FEED-DRIVING MECHANISM.

page_text: also resting in the plug, the two shafts being connected at one end by a gear e
and a pinion, two to one in diameter. By this means, the shaft turns the
shaft d. The plug is formed with an overhanging flange through which bolts pass
to secure the plug rigidly to the turret. The outer face of the head of the plug
is counterbored, as shown in Figures 23 and 24 and 26, in which to receive the
gear and pinion f' flush with its surface. The shafts and terminate in
equal overhanging threaded ends, to which is fitted an interchangeable grooved
hub g. This hub carries a shiftable stud 2, which operates a feed rod ?,
Figures 1, 11, 23, 26 and 48, and it is usually provided with a traverse screw to
move the stud longitudinally within the hub.
This machine is calculated to have the tool cut either both ways across the face
of the gear or only in one direction, as may be required. If cutting both ways, the
hub g is put upon the quicker shaft d² to feed twice to each revolution of the
driving gear for the tool. If cutting in one direction only, the hub is put
upon the lower shaft c² to feed only once to a revolution of the gear /.
THE FEED MECHANISM.
By
The circular toothed segment H, Figures 1, 3, 11 aud 23, is concentric with the
pivot a of the turret, and formed with circular T-shaped channels 12, Figures 1, 3
and 16. The base block I rests directly upon this segment and is secured thereto
by bolts n passing down into the grooves. Tongues n', Figures 15 and 16, of
the base block project into the grooves to hold the base block in place.
loosening the bolts, the base block with its superincumbent parts may be shifted
longitudinally upon the segment. The base block, which is sectoral in plan, is
formed with a circular T-shaped longitudinal race or cavity o³, Figures 2, 16
and 23, in its upper side; and upon the block, a base plate Y rests, having a part
projecting into said race o². The base block is also provided with a circular
toothed rack, as shown, in the race o³, forming a part of the inner side wall
of the race.
A feed stand Z, Figures 11, 14, 15 and 23, is secured rigidly to the base plate Y
by clamping bolts p², and formed with a vertical central opening to receive a feed
post A The feed post has a journal bearing in the stand, and it is formed with a
collar occupying a cavity s in the stand to support the post in place. Near its
lower end, the feed post is provided with a rigid pinion to engage the teeth of
the rack. The plate Y is formed with a vertical circular recess ³, Figures 2, 15
and 16, in which to receive the pinion and a smaller recess w³ to receive the lower
reduced end of the post and to form a journal bearing therefor.
A worm gear, Figures 1, 11, 15 and 23, is placed upon the post immediately
above the collar adapted to turn independently of the post. A horizontal
tangent shaft y2, Figures 23 and 48, is held in bearings 3, Figure 1, rigid with the
stand Z upon which is secured a worm a³, Figures 1 and 15, to turn the gear.
Rigid with the tangent shaft is also a ratchet &, Figures 1 and 48. This ratchet
is actuated by a pawl c³, held to turn upon a simple stud fixed in a pawl carrier d³,
Figures 1, 11, and 23, adapted to turn freely upon the shaft.
The feed rod, which passes near the pawl carrier, is provided with a shiftable
head e, held upon a stud frigid in the pawl carrier. The head turns upon the
stud as with a journal bearing; and, by means of it and the feed rod, the feed-
actuating hub, Figure 23, is enabled to rock the pawl carrier and so turn the
ratchet and the shaft y³.
The pawl, shown in reverse position in Figure 50, is formed with two unequal
conical cavities, in which a pointed detent, Figure 49, is urged by a spring,
said detent and spring being held in a cavity in the adjacent part of the pawl
carrier. When the pawl is turned to engage the ratchet, as shown in full lines
in Figure 48, the detent enters the large cavity and, by pressing against its inclined
side, holds the pawl against the ratchet. To throw the pawl out of action, it is
shifted by the attendant to the position indicated by dotted lines in Figures 48

page_text: and 49, in which position the detent enters the small cavity and holds the pawl
clear from the ratchet.
The shaft is provided with a rigid hand wheel at its extreme outer end, by
means of which the attendant who stands at A', Figure may turn the worm gear
independently of the actuating mechanism for said shaft.
Now it will be understood that, if the connection between the worm gear and
the feed post be such that the latter is turned by the former, the base plate Y
with the feed mechanism and tangent arm will be moved upon the base block on
account of the pinion u rolling along the toothed rack of the base block, the
turret swinging accordingly that is to say, the action of the feed serves to swing
the turret and move the tool toward the work by sliding the base plate along its
bearing upon the fixed base block. The worm gear and the post are caused to
co-act or turn together at intervals, by the following means:-
:
The worm gear usually made of composition is formed with a series of fine
radial teeth o, Figures 15 and 21, in its upper side, the teeth in practice being
cut in a ring of case-hardened iron inserted rigidly in the gear. Above the
gear, upon the post, is a circular tilting ring or rocker m³, Figure 19, formed
with teeth n on a portion only of the rocker to engage the teeth of the
gear as shown in Figure 22. This rocker does not closely fit the post all
round, but at two opposite side its interior is made flaring, as shown in Figures 15
and 19. It is held to the post by a transverse pin p³ crossing the axis of the post
at the middle plane of the rocker, by means of which pin and the flaring interior,
the rocker is permitted to tilt or rock vertically on the post, as indicated by dotted
lines in Figure 15. When the rocker is horizontal, its teeth engage the teeth of
the worm gear, and both must move together; but, when in its tilted position, the
teeth are disengaged and the rocker and the gear move independently of each other.
When the teeth of the two parts engage each other, the feed is said to be "thrown
in" and the tool is urged against the work.
When the tool has cut to the proper depth into the blank in any given case, the
feed has to be automatically thrown off to arrest the progress of the tool.
This is accomplished as follows:-
The rocker is formed with a laterally extended part in a vertical cavity in which
is inserted a lifter or tilter ³, Figures 15, 19 and 21, having its lower end in
contact with the worm gear, as shown. The axis of the lifter is parallel with the
axis of the post, and the lifter is urged downward against the gear by a spring ³,
the action of which tends to tilt the rocker and throw the teeth out of engagement.
Above the rocker upon the feed post is a feed-relief lever t³, Figures 15, 18, 20
and 21, fitted also to tilt as indicated by dotted lines in Figure 15 and free to move
horizontally upon the post. Above the lever upon the post, is a hubbed plate v³,
Figures 11, 15, 17, 20 and 21, acting as a confiner for the lever and the rocker, the
plate being secured to the post by a set screw u³, Figure 1, so as to be shiftable
thereon. A sufficient space is left between the lever and the confiner to allow
the former room to tilt as stated.
The feed-relief lever is provided at its upper side with a rigid longitudinal
tooth Figures 15, 18 and 20, adapted normally to bear against the adjacent
surface of the confiner. The surface of the confiner above the tooth is plain, save
as to a notch, Figure 17, into which the tooth may enter when at any time it
and said notch are presented to each other. Now when the tooth is out of the
notch and bears against the surface of the continer, the lever is confined or held
down to a horizontal position, and in turn presses the teeth of the rocker into
the teeth of the gear against the action of the spring s³. But when the lever
and the confiner are by any means brought relatively into positions in which
the tooth may enter the notch, the spring immediately lifts the rocker and
clears it.

page_text: Above the confiner, a cap y' is screw-threaded into the upper end of the post;
and the confiner is provided with a hand lever 2, Figures 1 and 23, by means of
which the attendant may move the tangent arm and the tool toward or from the
work.
When the tooth enters the notch, the feed instantly ceases, for, the gear being
free to turn upon the post, the latter is not affected by the continued action of the
feed-driving mechanism.
To control the feed-relief lever so as to cause the notch to be presented to the
tooth at the proper time to stop the feed, a horizontal circular grooved segment a*
is provided, Figures 1, 23, 40, and 42, concentric with the feed post over which
the lever swings. To this segment are secured two stops b and c, which, arresting
the horizontal motion of the lever in either direction, serve to control the latter.
When the tool is being fed against the work, the lever is in advance of the notch,
the parts moving relatively in the directions indicated by full line curved arrows
in Figure 21. Now, when the lever encounters the stop 6, Figure 1, its motion
will be arrested, but the confiner will continue to move forward and the tool con-
tinue to feed. When, however, the notch a arrives at or overtakes the tooth, the
lever will suddenly rise from the action of the spring 83, releasing the rocker and
the worm gear, and the feed will instantly cease. That this action of the parts
will be quite sudden, will be clearly understood by viewing Figure 20; for, when
the tooth and the notch arrive at the relative positions there shown, the tooth will
quickly slide into the notch and release the rocker, as stated.
Now if, after the feed has been thus terminated, the parts be by any means
turned to move in the opposite direction (indicated by dotted arrows in Figure 21)
the lever will encounter the other stop e, and the tooth will be pushed out of the
notch.
This will again depress the rocker and throw the feed into action. When the
parts move in the directions indicated by dotted arrows in Figure 21, the base
plate and the feed mechanism with the tangent arm will be moved back along the
base block on account of the action of the pinion u³ upon the toothed rack t
which will withdraw the tool from the work.
The stops and care shiftable around the segment a', each being held to
place by ordinary clamping screws d passing through them and threaded into
nuts in the groove of the segment, one of said nuts being shown at et in Figures 41
and 42. By shifting or adjusting these stops, the depth to which the tool will be
fed into the work in any given case may be accurately determined and likewise
the distance the tool will be drawn back from the work.
It is preferred to make the stop c¹ yielding by providing a horizontal bumper *,
Figures 40, 41 and 42, for the lever to encounter, said bumper being actuated by
a spring back of it, as shown. The rear end of the bumper being threaded
and provided with a screw nut * enables the operator to adjust the tension of
the spring at pleasure.
The feed mechanism is directly in the rear of the tangent arm, and the two
parts are so connected that, while the arm may move vertically through short
distances independently of the feed mechanism, both the latter and the arm move
together in horizontal directions. The feed stand Z is formed with a horizontal
rectangular cavity, Figure 11, near the arm, in which is closely fitted a
substantially cubical block adapted to move laterally through short distances in
a line parallel with the arm.
To the rear vertical face of the arm and over the cavity is rigidly secured a
bracket, Figures 1, 11 and 23, formed with a vertical downwardly projecting
offset stem m, which passes into and through the block_**, fitting accurately
therein, but so as to move freely in a vertical direction. Now, as the block can
have no lateral motion in the cavity in a line toward or from the arm, it follows
that the latter and the feed mechanism must always move together in horizontal
directions when the tool is moved toward or from the work, but that the arm may
move vertically independent of the feed mechanism.

page_text: THE PULL-BACK MECHANISM.
When the tool in any given case has been fed to the proper depth into the
blank and the feed thrown off, the tool must be quickly withdrawn from the blank
and out of the way before the latter is indexed. The tool is withdrawn by sliding
the base plate back upon the base block, the arm moving with it, which is effected
as follows:-
B' is a holding arm, Figures 11, 14, 23 and 27, made rigid with the base block,
to which is pivoted a bent lever C adapted to swing in a vertical plane. The
short arm of this lever is joined to the tangent arm D or to some convenient part
of the mechanism supported as, for instance, to a clamping bolt p² by a con-
necting barn, as shown, the joint at either end of the bar being free to move.
The long end of the lever is adapted to hold a shiftable weight D¹, which, when
unopposed, serves to keep the tangent arm swung back from the work.
When the tangent arm is moved toward the work by the feed mechanism, it is
done against the action of the weight. For instance, referring to Figure 27, when
the tool is commencing to act upon the blank, the lever C¹ and associated parts
occupy the positions shown in full lines; but, while the tool is being fed to its
extreme depth into the work, the lever and associated parts are gradually moved
to the positions shown by dotted lines. Now the instant the toothed rocker of the
feed mechanism is tilted to release it from the worm gear, the lever C¹ will be
returned to the position shown by full lines in the figure, in which the cutting tool
is drawn clear from the blank. °
To prevent the weight pulling the parts back with too violent action when the
feed is thrown off, a vertical dash pot E¹ is employed rigid with the supporting
arm B¹ provided with a plunger F' connected with the lever, shown in longitudinal
section in Figure 23. At the bottom of the dash pot is a pet-cock o*, through
which air is supplied to the space below the plunger.
The opening through the pet-cock being small, the escape of air as the plunger
descends must be gradual, on account of which the plunger will be cushioned
upon the air beneath it and relieve the shock of the descending weight. By
regulating the opening through the pet-cock, the cushioning of the plunger may
be controlled.
After the tooth of the feed-relief lever enters the notch in the confiner by
the lever meeting the stop *, as stated, the lever and the confiner remain engaged
and move together when thrown back toward the yielding buffer by the pull-
back mechanism. The device is so arranged that the weight throws the parts back
sufficiently to cause the lever to sharply encounter the yielding buffer, the effect
of which is to throw the tooth out of the notch and depress the lever and the
rocker, which again throws the feed into action.
The contiguous faces of the notch and the tooth are inclined at an angle of
about 45 degrees, which permits the tooth to slide easily out of the notch.
The operation of the feed mechanism and the pull-back mechanism is such
that the former gradually moves the base plute Y with its superincumbent
parts, including the tangent arm, through a given distance in one direction, and
the latter moves the same parts suddenly in the opposite direction through the
same distance.
THE INDEXING MECHANISM.
After the tangent arm is thrown back by the pull-back mechanism and the
tool cleared from the blank, the latter is indexed, which is done by the following
means:-
G. Figure 8. is a tangent shaft for the worm gear G. Figures 1. 4 and 7. which
After the tangent arm is thrown back by the pull-back mechanism and the
tool cleared from the blank, the latter is indexed, which is done by the following
means:
G. Figure 8. is a tangent shaft for the worm gear G. Figures 1. 4 and 7. which
carries a worm H¹ to engage the gear. I is a horizontal hanger bolted rigidly to
the head-stock B, and the tangent shaft rests in bearings p p therein. The shaft
´ is formed with an enlarged overhanging part constituting collar, which, bearing

page_text: against the contiguous bearing pt prevents end travel of the shaft in one direction,
while set nuts, turned against the bearing on the opposite side, prevent end
travel of the shaft in the other direction. K' is a short extension shaft for G.
which, on account of the connecting parts, is practically in one piece with said
shaft G. To the shaft K' is secured a removable toothed pinion s, which is a
part of a system of gearing for turning G. A shaft is held parallel with
shaft G', in an extended part of the hanger I', and provided at one end with a
removable overhanging gear u', which, by means of a changeable compound inter-
mediate is adapted to turn the pinions and the shaft G. This train of gearing
with the means for holding and operating the compound intermediate is common
to lathes and similar machinery.
At the other end of the shaft is secured a gear L, which is turned indirectly
by means of a pinion w', Figures 1 and 5, held upon a shaft N', resting in a
horizontal bearing in the hanger I. The position of the shaft N¹ is such that its
axis is in line with the axis of the tangent shaft G'. The pinion w¹ and gear L'
are connected, by means of intermediate pinions y, held by a shiftable frog x,
Figures 1, 5 and 7. This frog, which is of common construction and operation, is
adapted to turn upon the shaft N' and to be set in either of two positions, so as to
bring one or the other of the intermediate pinions y in mesh with the gear L' for
the purpose of controlling the direction of motion of the tangent shaft G'.
The shaft N and the whole indexing mechanism is driven by a belt on the
friction pulley O¹ which is constructed as follows:-
The web of the pulley O¹, Figure 7, is a thin plate formed with a hub adapted
to turn freely upon the shaft N'. This web is inclosed by two circular discs **
and a as shown, the former disc being rigid with the shaft N' and the latter diso
turning with the shaft but being adapted to move longitudinally thereon. The
disc as is formed with an extended hub formed with a cavity in which is placed
upon the shaft a spiral spring confined by a nut c threaded upon the shaft and
adapted to enter the cavity in the hub. The web of the pulley and the contiguous.
faces of the discs are formed with annular depressions opposing each other in
which are placed rings of friction material as leather. The discs are not in
contact with the web of the pulley but a little apart therefrom, the contact between
said discs and the web being through the medium of the friction ringe. The
tendency of the spring is to press the disc a' against the web of the pulley and
the latter against the rigid disc 2; and by turning the nut one way or the other
to regulate the tension of the spring the friction at the leather rings may be
controlled.
The tensity of the friction is maintained at all times sufficient to enable the
continuously rotating pulley O' to turn the whole indexing mechanism, from which
it will be understood that unopposed the belt on said pulley would keep the blank
gear continually revolving. To hold the latter, while a tooth is being cut, a
detent for the indexing mechanism is interposed, the same being as follows.
The gear L' is provided upon its inner side with rigid lugs or stops e
Figure 6, opposing each other and near the periphery of the gear. A horizontal
detent bolt appearing in Figures 1 and 5, but better shown in Figure 12 is.
adapted to have its free end enter between the stops e e as shown, to prevent the
rotation of the gear. The bolt is held by a barrel y rigid in the hanger I, within
which a spiral spring upon the bolt presses against the collar of the latter in a
manner to force it against the gear. Thus normally the action of the indexing
mechanism will be arrested.
To temporarily withdraw the detent bolt to release the mechanism for the
purpose of indexing the blank, a horizontal longitudinal trip shaft, Figures 1, 4,
7, 13 and 28, is employed, resting in bearings in the frame beneath the head stock.
To the overhanging end of the barrel y over the trip shaft is rigidly secured a
downwardly-extending arm Figures 7 and 12, provided at its lower end with a
lengthened longitudinal hub, through the axis of which the trip shaft passes, as
appears in Figures 1, 4 and 13. The shalt turns freely in the hub the latter

page_text: forming a sort of a pendant bearing for the shaft. The pendant arm is
bifurcated at its lower end including the hub in the space between the branches of
which is inserted the hub of a detent-releasing arm provided with a spline m
Figure 13, which rests in a longitudinal groove n in the trip shaft, Figure 1. By
means of the groove and the spline the shaft and the releasing arm move together
as to rotatory motions of the former, but the arm may freely slide longitudinally
along the shaft independently of the latter. The detent bolt f* projects to some
distance beyond the outer end of the barrel and the releasing arm takes hold of
this projecting part, as shown in Figures 5 and 12. Upon each side of the
releasing arm upon the detent bolt are placed collars of rigid with the bolt between
which the arm may freely move but without lost motion. Now a slight turning of
the trip shaft toward the right as appears in Figures 7 and 13, will throw the
releasing arm and the detent bolt to the positions shown by dotted lines in
Figure 12. In this position the bolt is withdrawn from between the stops e of the
gear L which serves to temporarily release the latter and the whole indexing
mechanism, and allow the latter to act until the gear makes a complete revolution
and is again caught by the detent bolt.
THE TRIP MECHANISM.
The bed piece S, Figures 1, 3, 23 and 28 is formed with a circumferential
groove in which is fitted to slide a circular segment P¹ to which the turret C is
rigidly bolted so that both parts P¹ and C move together. This segment is formed
with a horizontal peripheral dovetail groove for holding bolts to adapted to
rigidly secure in place a downward extending shiftable trip arm u', as shown.
The trip shaft projects beyond the bearing p, to the overhanging end of which is
rigidly secured a crank arm v, see also Figures 29, 30 and 31. The crank arm is
provided with a pendant latch w held in a cavity therein and adapted to swing on
a pivot screw rigid in the crank arm. The latch is free to move toward the
left as appears in Figures 3, 29 and 30, but encounters a shoulder y' of the crank
arm when pushed toward the right. The trip arm us has its lower end turned
inward at right angles as shown in Figure 28 in position to engage the extreme
point of the latch when the turret is turned toward the right, as appears in
Figure 3.
The trip arm, when the pull back mechanism turns the turret backward or
toward the right, comes in contact with the latch, as indicated in Figure 29 and
turns the trip shaft through a small distance or until the parts assume the positions
indicated by dotted lines in Figures 29 and 12. This turning of the shaft, it will
be understood is against the action of the spring of the detent bolts, Figure 12;
and when the parts are in the positions shown by dotted lines in Figure 29 the
latch has swung high enough to clear the contiguous edge of the trip arm.
these relative positions of the parts are reached, the spring will immediately
cause the parts connected with the trip shaft at both ends to assuine their normal
positions shown in full lines.
When
The dotted positions of the parts shown in Figure 29 correspond with the dotted
positions of the parts shown in Figure 12; and likewise the full line positions of
the parts in the two figures correspond; that is to say, when the trip arm moves
the crank arm to the position shown by dotted lines in Figure 29, the detent bolt
will be withdrawn from the stops on the gear L' serving to release the latter and
set the indexing mechanism in motion.
The turning of the arm by the arm us through the short distance indicated
is but the work of a moment, but sufficiently long to release the gear L' and allow
it to turn. When the latch w clears as stated, the spring will immediately
drive the detent bolt forward against the gear, but the stop having then passel
on, on account of the rotation of the gear, the latter will make a complete
revolution before being again arrested by the bolt. During this turning of the
gear the bolt simply slides around against its smooth surface until the inclined end

page_text: It frequently becomes necessary when using the finishing tools to adjust the work
to the tool by turning the blank slightly in one direction or the other without
disturbing the indexing mechanism.
To provide for this adjustment an adjusting cylinder R, Figures 1, 4, 7, 8
and 10 is employed, interposed somewhere in the indexing mechanism between the
shafts N' and G', preferably upon the latter or upon the shaft t. As shown, this
cylinder consists of a main part 2 and a corresponding minor part a. The
part is made rigid with the shaft G¹ and formed with an annular T-shaped
groove 66 in its face to receive clamping bolts cc as shown, the bolts being inserted
through a square opening in the back of the piece. The bolts hold the part a
rigid with the part 2 and the extreme reduced end of the shaft G¹ enters aⓇ a short
distance to centre the latter. The short shaft K³ is rigid in a so that when the
bolts are tightened the shaft K' is practically a continuation of the shaft G¹, both
parts turning together.
The periphery of the part adjacent to a is divided into a scale of equal parts
as appears in Figures 1, 7 and 10, forty divisions more or less, as may be found
convenient, being employed. A single corresponding mark is formed on the
adjacent part of a as indicated for the relative positions of the two parts. Now
as the part 2 is rigid with the shaft G', then by loosening the bolts' said shaft
may be turned independently of the part a' and all the gearing between it and the
shaft N'. By this means the work may be brought exactly to the tool by turning
it as may be required. After the adjustment is made the bolts are again
tightened.
THE FORM MECHANISM.
In planing gears in this machine the faces of the teeth are copied from forms as
in other machines of this class. The extreme lower corner of the tangent arm is
provided with a rigid but removable form rider e Figures 11, 23, 37, 36 and 38.
The form rider inclines downward and backward in position to bear upon an
inclined form S' as shown. The form used for rough-cutting the teeth is straight
and horizontal, as shown. For finishing the faces of the teeth curved forms T T¹
are employed. These forms are held in a form holder U' secured indirectly to the
base block I of the feed mechanism. A vertical grooved body V' is secured
rigidly to the base block by a screw in which body is fitted a slide W' adapted
to move vertically. The slide is formed with a projecting inclined part X¹ against
D

page_text: which the form holder is held upon a stud 9 rigid in the slide. A clamping nut h
secures the form holder rigidly in place, and by loosening which the holder may
be turned to bring either form into action as may be required. A detent of some
simple kind is employed to accurately set the form holder in each of its positions
of adjustment.
For vertically adjusting the forms a lifting screw Figures 34 and 35, is
employed threaded in a bearing in the part Vin position to bear upward against
a part of the slide. This lifting screw is provided with a set nut k to hold it in
place after adjusting the form. The body V₁ overhangs and partly covers the
teeth of the segment H and it is provided with a pinion Yi upon a vertical
shaft m turning in bearings in V1, Figures 11, 23, 34, 36 and 37, the pinion being
in position to engage the teeth 16. The shaft m is squared at n to receive a
wrench for turning it for the purpose of moving the base block I around upon the
segment, the holding bolts m² being first loosened. When thus shifting the base
block, the feed mechanism, the tangent arm, the pull-back mechanism and the form
holding mechanism go with it, all these parts being secured to or carried by the
base block. The shifting of the base block with its dependent parts is for the
purpose of adapting the machine for planing gears of different diameters and
bevels.
The head stock B is adapted to be moved longitudinally upon the frame by a
horizontal traverse screw Z¹ Figures 1 and 7, beneath it. This screw rests in a
bearing of rigid with the frame and is operated by an overhanging crank po.
As the machine is constructed the indexing mechanism is at one end and the
trip mechanism at the other end of the frame.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, as communicated to me by
my foreign correspondents, I declare that what I claim is :-
1. A gear planer provided with an indexing mechanism and a detent or stop for
said mechanism, in combination with a pivotal turret, an arm carrying the cutting
tool held by the turret and means to give the turret a retrograde motion and actuate
said detent or stop, substantially as shown and described.
2. A gear planer provided with an indexing mechanism, in combination with a
pivotal turret, an arm carrying the cutting tool held by the turret, mechanism to
turn the turret to move the tool backward, a detent for the indexing mechanism,
and a trip arm carried by the turret to actuate the detent, substantially as shown
and described.
3. A gear planer having an indexing mechanism and a detent therefor in com-
bination with a pivotal turret, an arm carrying the cutting tool held by the turret,
a feed mechanism to turn the turret in one direction, a pull-back mechanism to turn
the turret in an opposite direction, and a trip for the detent operated by the pull-
back mechanism, substantially as shown and described.
4. An automatic gear planer having an indexing mechanism and a detent therefor,
in combination with a continuously rotating friction wheel to drive the indexing
mechanism, and means to operate the detent, substantially as shown and described.
5. An automatic gear planer having an indexing mechanism consisting of a
driving shaft and a worm and intermediate gearing connecting said shaft and worm,
an adjuster for the work interposed between said shaft and the worm and connected
with both by said intermediate gearing, said adjuster consisting of two parts joined,
one part adapted to turn the worm and the other part adapted to be turned by the
shaft, said parts of the adjuster being adapted to be turned independently of ench
other, substantially as shown and described.
6. An automatic gear planer comprising an indexing mechanism having a rotatory
gear L' provided with a stop, a spring-pressed bolt adapted to engage said stop, a
shaft adjacent to said gear and an arm on the shaft adapted to operate said spring-
pressed bolt, and means to turn the shaft, substantially as shown and described.
7. An automatic gear planer comprising an indexing mechanism having a rotatory

page_text: gear L¹ provided with a stop, a spring-pressed bolt adapted to engage said stop, a
shaft adjacent to the gear and an arm on the shaft adapted to operate said bolt, and
means to turn the shaft, said arm being adapted to turn with the shaft but to slide
longitudinally thereon, substantially as and for the purpose specified.
8. An automatic gear planer having a turret or body C supporting parallel
shafts d' and c connected by gearing adapted to cause them to turn with unequal
velocities, a crank arm adapted to be placed upon either shaft, and means to rotate
said shafts, substantially as shown and set forth.
9. A gear planer having a frame, a pivotal turret supported by the frame, a
tool-carrying arm held by the turret, a horizontal base block adapted to be made
rigid relative to the frame, a base plate adapted to slide upon the base block, a feed
mechanism controlling the tool-carrying arm rigid with the base plate, a weighted
lever connected with the base block and with the parts supported by the latter, the
feed mechanism serving to move the parts upon the base block in one direction and
the weighted lever adapted to move said parts in the opposite direction, substan-
tially as shown and described.
10. A gear planer having a frame, a horizontal toothed segment rigid with the
frame, a shiftable base block held by the segment, a feed mechanism held by the
base block, a tool-carrying arm controlled by the feed mechanism, a toothed pinion
held in bearings beneath said arm rigid with the base block adapted to engage the
teeth of the segment, said pinion being adapted to move the base block with its
superincumbent parts along the segment, substantially as shown and described.
11. A gear planer having a pivotal turret and a rigid base block, in combination
with a feed mechanism held by the base block, a tool-carrying arm held by the
turret and controlled by the feed mechanism, the base block being formed with a
series of gear teeth, the feed mechanism having a vertical rotatory post, a pinion
on the post to engage the teeth of the base block, and means to turn the post,
substantially as shown and described.
12. A gear planer having a toothed base block and a base plate adapted to slide
thereon, in combination with a feed stand rigid with the base plate, a rotatory post
held by the stand, a pinion on the post to co-act with the base block, a worm
toothed gear on the post, a toothed rocker held to turn with the post and adapted
to engage the worm gear, a tilter for the rocker, a toothed relief-lever on the post
co-acting with the rocker, a notched plate over the lever rigid with the post, and a
stop or actuator for said lever, and nieans to turn the worm gear, substantially as
shown and described.
13. A gear planer having an indexing mechanism, a feed mechanism, a tool-
carrying arm controlled by the feed mechanism, a pull-back mechanism for the
arm, a detent for the indexing mechanism, and a trip for the detent operated by
the pull-back mechanism, the latter acting upon the arm in advance of the action
of the indexing mechanism, substantially as shown and described.
14. A gear planer having a pivotal turret, a tool-carrying arm held by the turret,
a stationary base block, a feed mechanism held movably upon the base block and
controlling said arm, a weighted lever connected with the base block and with the
mechanism upon the latter, and a dash pot or buffer for the lever, substantially as
and for the purpose specified.
15. A gear planer having a pivotal turret, a shaft held by the turret, a crank
arm on the shaft, a tool-carrying arm held by the turret, a tool-carrying recipro-
cating slide in said arm, and an adjustable connecting bar for said crank arm and
the tool-carrying slide, and means to turn the crank arm, substantially as shown
and described.
16. An automatic gear planer having a frame and an indexing mechanism sup-
ported thereby, a detent for the indexing mechanism, a pivotal turret supported by
the frame, an actuator for the detent controlled by the turret, said actuator being
at one end of the frame and the indexing mechanism at the opposite end of the
frame with a shaft to connect the actuator and the indexing mechanism, substantially
as shown and described.

page_text: 17. A gear planer having a toothed base block, in combination with a feed stand
supported by the base block, a rotatory post in the feed stand, a pinion on the post
to co-act with the base block, a worm gear on the post, a rocker held by the post
to turn therewith and adapted to engage the worm gear, a tilter for the rocker, a
toothed relief lever over the rocker, a notched plate rigid with the post co-acting
with the lever, a yielding stop for the lever, means to turn the latter against said
stop, substantially as shown and described.
Dated this 19th day of July 1894.
WM. P. THOMPSON & Co.,
Agents.