Automatic Clamp for Supporting the Rim of the Blank in Gear. Cutting Machines.
Year: 1899

page_text: Date of Application, 9th Feb., 1899
Complete Specification Left, 17th Oct., 1899-Accepted, 9th Feb., 1900
PROVISIONAL SPECIFICATION.
Automatic Clamp for Supporting the Rim of the Blank in Gear.
Cutting Machines.
I, ULRICH EBERHARDT, residing at the City of Newark, County of Essex,
State of New Jersey, U.S.A., Engineer, do hereby declare the nature of this
invention to be as follows:-
The object of the present invention is to furnish the means of holding the blank
more firmly during the operation of cutting the teeth therein, and the invention
consists of jaws adapted to clamp the rim of the blank during the
cutting operation adjacent to the cutting point, and to automatically release the
same during the shifting of the blank for cutting the succeeding teeth.
In automatic gear cutting machines it is common to fix the circular blank
upon a mandrel which determines the position of the blank during the cutting
of each tooth, the cutter being first fed through the blank and then retracted
while the blank is shifted to its succeeding position; and all of these operations
are repeated by automatic mechanism so that when the blank and mechanism
are properly adjusted, the teeth may be cut in the entire wheel without further
attention from the operator. Where the machine is employed to cut a very
large blank, or a blank is supported, owing to the small size of its bore, upon a
mandrel which is incapable of holding it firmly, it is désirable to tightly clamp
and hold the rim of the blank adjacent to the cutter, to prevent the blank
from springing or yielding during the cutting operation. Such yielding not
only causes an inaccuracy in the shape of the teeth, but a roughness of their
surface, owing to their vibration or chattering.
In the present invention, jaws are provided to automatically clamp the blank
upon its front and rear sides at the proper time, to hold the same rigidly during
the cutting operation, and automatically release the blank, when necessary, for
shifting. The blank is thus securely held during the cutting operation, and re-
leased during the shifting operation, without any attention on the part of the
workman.
Both of the clamping jaws may be moved to release the blank, but in practice
the jaw between the rear side of the blank and the frame or column of the
machine, may remain adjusted in contact with the blank, and only the front
jaw be reciprocated.
Wheels of small diameter require no such support during the cutting of the
teeth, and the rims of wheels of large diameter vary very slightly in their posi-
tion adjacent to the edge of the cutter, and clamping jaws arranged to embrace
a large wheel may therefore, without material alteration in position, be made to
embrace others of smaller diameter. The mechanism for reciprocating the mov-
able jaw is arranged-to lock the same immovably when in contact with the blank,
and such jaw reciprocating mechanism is preferably actuated or controlled by
the movements of the cutter head, as its operation is effected during the retrac-
tion of such cutter head from the notch which the cutter forms in the blank.
In automatic gear cutting machines, the mechanism for shifting the blank
(for cutting a succeeding tooth) is actuated when the cutter is withdrawn there-

page_text: from, and the clamping jaw in the present invention is therefore operated to
release it from the blank before the shifting mechanism rotates the latter, and
to press it upon the blank as soon as the shifting mechanism has operated, and
before the cutter commences to form the succeeding tooth.
As all these operations have a definite time-relation to the retracting of the
cutter slide, it is common to actuate the blank-shifting mechanism by connection
with the cutter slide, and the cutter slide is preferably utilized, in the present
invention, to actuate the jaw clamping device. The jaw clamping mechanism
may however be actuated by any other part of a gear cutting machine, which
operates synchronously with the retraction of the cutter slide, as for instance,
parts of the feed reversing mechanism and all of the shafts and gears connected
therewith.
The jaws are mounted upon a jaw carrier consisting of a parallel bar or guide,
and having the jaws fitted movably thereon. Such carrier is preferably formed
with an adjustable foot-plate by which it is held parallel with the mandrel and
may be set close to the rim of the blank. One of the jaws is fixed adjustably
upon the carrier in contact with the rear side of the blank, to sustain the pressure
produced as the cutter is fed into the blank, and the other jaw is held movably
upon the carrier so as to be pressed upon the blank during the cutting operation.
In the preferred construction, a so-called clamp-rod is extended from the
movable jaw through the fixed jaw and through the foot-plate to a suitable
mechanism for reciprocating it at the beginning and end of the shifting opera-
tion. Such mechanism may consist of a toggle or of a wedge, either of which
when moved in one direction operates to press the jaw firmly upon the blank
and to lock the same thereon. The reciprocating mechanism may be actuated
directly by the cutter head through the agency of movable arms pressed in op-
posite directions by the cutter head when the cutter is retracted from the blank.
The reciprocating mechanism may also be conveniently operated, in automatic
gear cutting machines, by a suitable detachable connection to the rotating shaft
which is provided in such machines to reciprocate the cutter head and rotate
the cutter spindle.
In such a case, an eccentric or crank is connected with the wedge or toggle
forming the jaw reciprocating mechanism and is driven from the said rotating
shaft by a clutch which is suitably actuated by the movements of the cutter
head. The clutch may be thus actuated by means of a trip lever and a dog for
moving the same, which dog is operated twice by the cutter head at suitable
intervals of time (during its retraction from the blank), to unclamp the blank
for shifting, and to clamp it again in readiness for cutting.
The jaw reciprocating mechanism may also be actuated by a spring to press
the movable jaw normally upon the blank and to lock it in such position, and
a connection may be made between the spring and the cutter head whereby the
force of the spring is neutralized when the cutter head is retracted from the
blank, so that the pressure upon the movable jaw is relaxed while the blank
is shifted. The invention may be practiced by moving both of the jaws; but I
find it more convenient to move the outer jaw only, and I make the same adjust-
able upon the clamping rod so as to press upon the outer side of blanks of
various thicknesses.
The essential part of the invention is the provision of the clamping jaw or
jaws with means for pressing one or both of the jaws upon the blank during
the cutting operation, and means for releasing one or both of the jaws from the
blank during the shifting of the latter, and the means of supporting the jaws
and reciprocating them is therefore immaterial.
Digned at No. 10, Wall Street, New York, N.Y., this 31st day of January
1000

page_text: :
Automatic Clamp for Supporting the Rim of the Blank in Gear
Cutting Machines..
I, ULRICH EBERHARDT, residing at the City of Newark, County of Essex,
State of New Jersey, U.S.A., Engineer, do hereby declare the nature of this
invention and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement;―
The object of the present invention is to furnish a means of holding the blank
more firmly during the operation of cutting the teeth therein.
The invention consists of jaws adapted to clamp the rim of the blank during
the cutting operation adjacent to the cutting-point and to automatically release
the same during the shifting of the blank for cutting the succeeding teeth. In
automatic gear-cutting machines it is common to fix the circular blank upon a
mandrel, which determines the position of the blank during the cutting of each
tooth, the cutter being first fed through the blank and then retracted while the
blank is shifted to its succeeding position, and all of these operations are repeated
by automatic mechanism, so that when the blank and mechanism are properly
adjusted the teeth may be cut in the entire wheel without further attention from
the operator.
Where the machine is employed to cut a very large blank or a blank is sup-
ported, owing to the small size of its bore, upon a mandrel which is incapable of
holding it firmly, it is desirable to tightly clamp and hold the rim of the blank
adjacent to the cutter to prevent the blank from springing or yielding during
the cutting operation.
In the present invention jaws are provided to automatically clamp the blank
upon its front and rear sides at the proper time to hold the same rigidly during
the cutting operation and automatically release the blank when necessary for
shifting. The blank is thus securely held during the cutting operation and
released during the shifting operation without any attention on the part of the
workman. Both of the clamping-jaws may be moved to release the blank; but
in practice the jaw between the rear side of the blank and the frame or column
of the machine may remain adjusted in contact with the blank and only the front
jaw be reciprocated.
The mechanism for reciprocating the movable jaw is arranged to lock the same
immovably when in contact with the blank, and such jaw-reciprocating mech-
anism is preferably actuated or controlled by the movements of the cutter-bead,
as its operation is effected during the retraction of such cutter-head from the
notch which the cutter forms in the blank.
In the annexed drawings several varieties of mechanism are shown for ac-
tuating the clamp in such cutter-head; but it should be understood that the
clamps and their mechanism may be modified in form to adapt them to other
gear-cutting machines.
In the drawings, Fig. 1 is a plan of a gear-cutter provided with a wedge-
slide and rotary eccentric to actuate the clamping-jaw, with a part of the apparatus
omitted. for feeding the cutter-head and intermittently rotating the blank, as
sucli devices are old and form no part of the present invention. Fig. 2 is a
side elevation Fig. 3 a front elevation with section of cutter-head D on
line 3, 3, in Fig. 2, and Fig. 4 a rear elevation showing such parts of the
machine as are necessary to illustrate the form of invention shown in Fig. 1.
In these figures the top of the column and part of the blank are broken off
for want of room; and the guide-arm at the rear end of the clamp-rod in Fig. 2,
as well as the bed for the cutter-head in Fig. 3, are shown in section where

page_text: hatched. Fig. 5 is an elevation similar to Fig. 2 with a wedge-slide and an
oscillating frog to actuate the clamping-jaw, and the jaw-carrier adjustable ver-
tically upon the column. Fig. 6 is a front elevation of the column and jaw-
carrier with dotted lines showing the adjustment required for different blanks.
Fig. 7 is a side elevation of a gear-cutter with alternative (toggle) mechanism
for actuating the clamping-jaw, and Fig. 8 is an end elevation of the carrier and
clamping-jaws upon a larger scale than the other figures. Fig. 9 is a vertical
longitudinal section of the clutch shown upon the shaft s in Figs. 1 and 2, for
automatically actuating the clamping-jaws.
A designates the bed of the machine supporting the cutter-head D to move
horizontally and having at one end the column E, upon which the mandrel-bear-
ing is adjustable vertically and fitted with sleeve G to carry the mandrel.
The worm and worm-wheel H (shown in Figs. 1 and 2) operate with suitable
mechanism to rotate the blank at intervals. The cutter-head is shown provided
with a feed-screw a, which is actuated by well-known devices to reciprocate the
cutter head and drive the cutter to and fro through the rim of the blank.
A driving-shaft J is shown, with driving-pulley J, connected by shaft L with
the means for reversing the feed of the cutter-head. A shifter-arm g² is shown
in Figs. 1 and 2 pivoted upon a casing N2, which in practice contains the mech-
anism for rotating the feed-screw. The driving-shaft is shown connected with
gears K and K and friction-clutch I, which turns the worm-wheel H and
sleeve G. A screw 12 is shown in Fig. 7 provided with hand-wheel F to adjust
the mandrel-bearing to and from the cutter. Fig. 3 shows the relation of the
clamping-jaw to the cutter u, the cutter being shown at the bottom of the
blank and the clamping-jaw c applied to the rim of the blank at one side of
the cutter.
The carrier M, having parallel edges with disk-like foot-plate M, is mounted
upon a bracket N at one side of the column E and is shown swiveled thereon,
so as to turn the jaws toward the rim of the wheel whatever its curvature. The
foot-plate is shown in Fig. 3, with slots and bolts to secure it when adjusted.
A jaw is shown at the rear side of the blank fitted movably to the carrier M
and may be held in contact with the blank by any suitable means. In Fig. 2
a set-screw d is shown tapped into the jaw and projected therefrom against the
foot-plate M and provided with a jam-nut to hold it when adjusted.
The screw serves to adjust the jaw in contact with the blank, as the distance of
the latter from the foot-plate may vary, and it also sustains the pressure upon
the blank when clamped by the jaw c. The screw may be used without the
jam-nut, as shown in Figs. 5 and 7, and is omitted from the jaw in Fig. 1, as
any other suitable means may be used to hold the jaw from moving upon the
carrier. The rear side of the bracket N is provided with a guide-arm I', and a
clamping-rod extends through the center of the foot-plate and through the
jaws cand e and projects past the guide-arm, which is constructed to support
its outer end.
In Fig. 2 the support is furnished by a head-piece e, which is attached to the
rod and provided near its end with a roll e¹. The head-piece is forked, as shown
in Fig. 1, and a slide f is extended transversely through the guide-arm and
through the slot in the head-piece and is provided adjacent to the roll e¹ with
a wedge-surface o, which operates when the slide is suitably moved, as shown
in Fig. 2, to draw the clamping-rod endwise and press the clamping-jaw c against
the blank when the nut is suitably adjusted. When thus clamped, the side of
the slide, which is furnished with a parallel seat o¹ adjacent to the
wedge, serves to lock the jaw against the blank, and thus relieve
the mechanism which reciprocates the slide from any strain during
the cutting of the blank.
A spring på presses the rod, with the roll, normally toward the slide, and when
the movement of the slide is reversed the roll enters a notch o at the base of the

page_text: wedge and the clamp is released from the blank, as shown in Fig. 5. The slide
may be reciprocated by various means, but must be suitably moved to release the
blank from the pressure of the jaw c during the shifting of the blank. Such
shifting is commenced upon the retracting movement of the cutter-head as soon
as the cutter is drawn clear from the space g in the blank, and the reciprocating
mechanism for the slide may thus be actuated by the movement of the cutter-
head at such time.
i
and
The
In Figs. 1 to 4 an eccentric is shown connected to the slide by link
rotated by gears and j, the gear being fitted loosely upon its shaft s.
eccentric is shown in its lowest position, in which the clamping-jaw c is locked
against the blank, and a half revolution of the eccentric throws the slide upward
and holds the jaw released. A subsequent semirevolution of the eccentric
restores the slide to its initial position and clamps the jaw against the blank.
These movements are effected by intermittent rotations of the pinion, which is
one half the size of the wheel j.
The shaft sis continuously rotated by connection with the driving-pulley J2
and is provided with a hub m, (see Fig. 1 and 9,) having a notch m² in its front
side.
The pinion is held against the front of the hub by collar (see Fig. 3) and
a sliding key is inserted through the pinion and in practice is pressed nor-
mally toward the notch m' by a suitable spring_m². The key is formed with
a head a', by which it may be drawn out of the notch, and a wedge-shaped
latch is pivoted adjacent to the collar s', so as to move to and from the shaft s.
The latch is pressed normally against the shaft by spring 2 (see Fig. 2),
and when held in the position shown in Fig. 2 the head of the key engages the
point of the wedge and retracts the key from the revolving hub in and arrests
the movement of the eccentric in either its upper or lower position. The hub m
may be secured to the shaft s in any convenient manner and is shown pinned
thereto in Fig. 9, as well as the collar s¹, by which construction the pinion i
is held in place movably upon the shaft, so that it may turn freely when the
key n is withdrawn from the notch n¹.
The latch is connected by rod 2 with two trip-levers 73, hinged adjacent to
the cutter-head D.
A dog is pivoted adjustably to the cutter-head and constructed with foot q¹
to hold it rigidly as the cutter-head is retracted, so that it depresses the trip-
levers, but swings clear of the same, as indicated by dotted lines, when the
cutter-head advances to cut the blank. The dog is so adjusted upon the cutter-
head that when the cutter first clears the blank in its retractive movement the
dog trips the first lever and clutches the pinion to the shaft s, thus rotating the
eccentric one half a revolution and releasing the clamping-jaw c.
in
The blank-shifting mechanism then operates to rotate the blank, which is
effected before the retractive movement of the cutter-head brings the dog
contact with the second trip-lever 1, which then trips such lever and produces
another semirotation of the eccentric to lock the jaw against the blank before
the cutter-head advances to cut it. By this construction the cutter-head simply
actuates the trip levers, and the power to clamp and unclamp the jaw is fur-
nished by the rotating shaft: but the movement of the cutter-head may be made
to move the slide directly, as shown in Fig. 5. In this figure a double trip-
lever or so-called "frog" having arms 2 is oscillated by a dog q upon the
cutter-head.
The frog is connected with the slide by rods and bell-crank ³, and the
cutter-head shifts the slide f into the required opposite positions while the cutter
is withdrawn from the blank and when the cutter-head is moving backward
and forward during the shifting of the blank. The jaw is thus unclamped and
reclamped before the cutter begins the succeeding cut. Fig. 7 also shows a
construction in which the power to clamp the jaw is derived from the cutter-

page_text: head, toggle-links u being arranged to operate the rod and actuated by a bell-
crank and connections with the cutter-head.
A lug is projected from the cutter-head, and a rod p is extended from the
bell-crank through such lug and provided with an adjustable collar p8.
A spring U is provided to normally straighten the toggle-links to clamp the
jaw C, and the retractive movement of the cutter-head bends the links, as shown
in Fig. 7, and thus unclamps the jaw, which is held in such position, during
the rotation of the blank, by a latch v, which is pivoted upon the bed of the
machine to engage a tooth upon the collar 28. A dog q is fixed upon the cutter-
head to press the tail of the latch as the cutter is advanced to cut the blank, thus
releasing the collar and permitting the spring U to reclamp the jaw.
In Figs. 1 to 4 the clamping device is shown mounted upon a bracket N,
which is a fixture upon the column E, and the clamping-jaws thus occupy a
fixed relation to the cutter u, although they may be tipped at various angles
by the turning of the foot-plate M, which sustains the jaw-carrier. Blanks
varying considerably in size may be clamped with such a construction, as the
rims of the blanks do not vary widely in position relative to the cutter u. A
blank is shown in full lines in Fig. 3, and a portion of two other blanks is
indicated by the dotted curves C and C, which blanks would be supported by
shifting the mandrel to the positions designated by the centers and ³. The
curves of these blanks all intersect the clamping-jaws, and could thus be held
by the clamp without changing its adjustment upon the column.
In Fig. 6 the bracket N is shown slotted, and the foot sustaining the carrier
is mounted upon a plate M2, which is vertically adjustable upon the bracket
and clamped thereto by bolts . Fig. 6 shows the various positions of the
carrier-foot upon the bracket to bring the jaws into exactly the same relation
to blanks of various sizes, the centers of the blanks and the requisite positions of
the mandrels to carry such blanks being indicated by the small circles . The
foot-plate is represented in dotted lines in the different required positions, with
a central circle showing the clamp-rod b, and the jaws are shown in the upper
and lower positions turned toward the center of the blank to which they are
applied.
The clamping-jaw may be moved outwardly upon the carrier M to admit
any number or thickness of blanks upon the mandrel, the nut 61 serving to adjust
the jaw tightly against the blank when the locking device is actuated. In like
manner the screw serves to set the adjustable jaw in contact with the rear
side of the blanks whatever their distance from the column or mandrel support.
With such construction it is only necessary to move one of the jaws to actuate
the clamping device; but both of the jaws may be made movable, if preferred,
and the form of the carrier and jaws varied to suit the requirements of different
machines.
As a variety of means is shown herein for actuating the clamping-jaw during
the retraction of the cutter from the blank, so that the blank may be shifted
before the cutter is fed forward, it will be understood that the invention is not
limited to the particular form described herein, but that the mechanism for thus
actuating the jaws may be varied to suit the construction of different machines.
The essential part of the invention is the combination, with the clamping-
jaw or jaws, of means to press the jaw upon the blank during the cutting
operation and means to release the jaw from the blank during the shifting of
the latter.
.
In automatic gear-cutting machines the mechanism for shifting the blank is
actuated when the cutter is withdrawn therefrom, and the clamping-jaw in the
present invention is therefore connected with suitable means to release it from
the blank before the shifting mechanism rotates the latter and to press it upon
the blank as soon as the shifting mechanism has operated and before the cutter
commences to form the succeeding tooth. As all these operations have a
definite time relation to the retraction of the cutter-slide, it is common to actuate

page_text: the blank-shifting mechanism by connection with the cutter-slide, and the
cutter-slide is also utilized in the present invention to actuate the jaw-clamping
device.
These parts may, however, be actuated by any other part of the machine which
operates synchronously with the retraction of the cutter-slide, as the parts of the
feed-reversing mechanism and all of the shafts and gears connected therewith.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what
I claim is;-
1. In a gear-cutting machine, the combination, with a driving-shaft and means
actuated thereby for intermittently rotating the blank and feeding a cutter
through the same, of mechanism for supporting the blank, clamping-jaws
arranged upon opposite sides of the blank, and means actuated by such driving-
shaft for automatically operating the jaws to clamp the blank during the cutting
operation and to release the same during the shifting operation.
2. In a gear-cutting machine, the combination, with a driving-shaft and means
actuated thereby for intermittently rotating the blank and feeding a cutter
through the same, of mechanism for supporting the blank, a clamping-jaw fixed
adjustably at one side of the blank, a jaw provided with means for reciprocating
it to and from the other side of the blank, and means actuated by such driving-
shaft for automatically pressing the movable jaw against the blank during the
cutting operation, and retracting it therefrom during the shifting of the blank,
substantially as herein set forth.
3. In a gear-cutting machine, the combination, with a driving-shaft and means
actuated thereby for intermittently rotating the blank and feeding a cutter
through the same, of a suitable support with a mandrel-bearing mounted thereon
and a mandrel to carry the blank, a jaw-carrier projected parallel with the man-
drel, a movable jaw held adjustably thereon to fit against one side of the blank,
a jaw provided with means for moving it to and from the opposite side of the
blank, and means actuated by the driving-shaft for automatically pressing the
movable jaw against the blank during the cutting operation, and retracting it
therefrom during the shifting of the blank, substantially as herein set forth.
4. In a gear-cutting machine having means for intermittently rotating the
blank and feeding a cutter through the same, the combination, with a suitable
support, of a mandrel-bearing and mandrel to carry the blank, a jaw-carrier
having parallel sides projected parallel with the mandrel, jaws movable thereon,
with a set-screw to adjust one of the jaws, and a clamp-rod with adjusting-nut,
extended through the other jaw and provided with means to clamp it upon the
blank, substantially as herein set forth.
5. In a gear-cutting machine having means for intermittently rotating the
blank and feeding a cutter through the same, the combination, with a suitable
support, of a mandrel-bearing and mandrel to carry the blank, a jaw-carrier
projected parallel with the mandrel, a jaw fixed adjustably upon the carrier,
a movable jaw with clamp-rod having roll attached thereto, and a wedge with
means for moving the same in contact with the roll to clamp such jaw against
the blank, substantially as herein set forth.
6. In a gear-cutting machine having means for intermittently rotating the
blank and feeding a cutter through the same, the combination, with a suitable
support, of a mandrel-bearing and mandrel to carry the blank, a cutter-head
to move the cutter through the blank, a jaw-carrier projected parallel with the
mandrel, a jaw fixed at one side of the blank. a jaw movable to and from the
opposite side of the blank, mechanism for reciprocating such movable jaw, and
means connected with the cutter-head for actuating such reciprocating mech-
anism during the retraction of the cutter from the blank.
7. In a gear-cutting machine having means for intermittently rotating the
blank and feeding a cutter through the same, the combination, with a suitable

page_text: support, of a mandrel-bearing and mandrel to carry the blank, a cutter-head
to move the cutter through the blank, a jaw-carrier projected parallel with the
mandrel, a jaw fixed at one side of the blank, a jaw movable to and from the
opposite side of the blank, means for locking the movable jaw against the blank,
mechanism for unlocking and retracting such jaw, and means connected with the
cutter-head for actuating such retracting mechanism, substantially as herein set
forth.
8. In a gear-cutting machine having a bed with cutter-head movable hori-
zontally thereon, and column with mandrél bearing adjustable vertically, and
means for intermittently rotating the blank and reciprocating the cutter-head,
the combination, with the column, of the bracket N having the foot-plate.
swiveled thereon with clamp-rod extended through the center of the same, a
guide for the rear end of the rod with mechanism to reciprocate the
same, the carrier M projected from the foot-plate parallel with the mandrel, with
fixed and movable jaws thereon, and nut to adjust the movable jaw upon the
clamp-rod, as and for the purpose set forth.
9. In a gear-cutting machine, the combination, with the gear-cutter frame.
having a mandrel-bearing and mandrel to carry the blank, of a shaft with means
for intermittently rotating the blank and actuating the cutter-feed. a cutter-
head to carry the cutter and move it through the blank, jaws adapted to clamp
the blank during the cutting operation, a rotary member, as an eccentric, to
actuate the jaws, a clutch connecting the shaft with said rotary member, and a
frin-lever with dop operated by the cutter-head to actuate the clutch during a
half rotation of such rotary member, substantially as herein shown and described.
10. In a gear-cutting machine, the combination. with the gear-cutter frame
having a mandrel-bearing and mandrel to carry the blank, of a shaft with means
for intermittently rotating the blank and actuating the cutter-feed. a cufter-
head to carry the cutter and move it through the blank. jaws adapted to clamp
the blank during the cutting operation, a rotary member, as an eccentric. to
actuate the jaws. a clutch connecting the shaft with said rotary member. a dom
upon the cutter-head. a rod connected with the clutch mechanism and with
two trip-levers arranged in the path of such dog. the dog and levers being
arranged to actuate the clutch twice while the cutter is, withdrawn from the
blank, so as to unclamp and clami the jaws hefore and after the shifting of the
blank, substantially as herein set forth.
11. The improved apparatus hereinbefore described with reference to the
accompanying drawing for carrying out the operations as set forth.
New York, N.Y., Dated this 30th day of June 1899.
THOMAS SEXTON CRANE,
Agent for Applicant.