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Àug. ‘14, i962
R. K. BROADBENT
3,048,864
VAMP CRIMPER
Filed Jan. 5, 1961
4 Sheets-Sheet 1
mw Nm.
_«___._ __«_I» :._
li
Invení'orf
Àug- 14, 1962
R. K. BROADBENT
3,048,864
VAMP CRIMPER
Filed Jan. 5, 1961
4 Sheets-Sheet 2
22
Iawezzêoß:
“
Roòerîifßa‘foadòeaaä,
Aug. 14, 1962
R. K. BROADBENT
3,048,864
VAMP CRIMPER
Filed Jan. 3, 1961
4 Sheets-Sheet 3
Aug. 14, 1962
R, K. BROADBENT
3,048,864
VAMP CRIMPER
Filed Jan. 5, 1961
4 Sheets-Sheet 4
3,048,864
c r'
United States Patent C LCC
Patented Aug. 14, 1962
2
l
provide cooperating pockets in the jaws when crimping
is to be done on shoe portions having parts of even
3,048,864
VAMP CRIMPER
Robert K. Broadbent, Lakeville, Mass., assignor to Geo.
Knight & Co., Inc., Brockton, Mass., .a corporation of
Massachusetts
Filed Jan. 3, 1961, Ser. No. 80,113
10 Claims. (Cl. i12-54.4)
greater thickness, as, for example, a full fitted blucher
This invention relates to improvements in shoe ma
chinery, and more particularly to improvements in ma
chinery for crimping an upper, or vamp, preparatory to
ing shoe. The clamping shoe gives substantial resistance
upper after lacing or an upper which includes a metal
buckle. The pockets may be provided at both the back
and front of the jaws to cope with particular types of
work.
Disposed between the jaws and in the line of vertical
travel of the blade, I employ a resiliently mounted clamp
to the downward travel of the blade between the jaws.
This results in the center line of the Vamp, which is en
lasting.
gaged by the blade, being very firmly clamped to the shoe
For many years it has been recognized that if the piece
with the result that no buckling or riding up of the
of leather which is to be the upper, or vamp, of a shoe
leather along the centerline thereof occurs.
is stretched in a particular manner (or crimped, as it is
These and other objects and features of my invention
called in the trade) it is more easily fitted to the last and
will appear as the description proceeds with the aid of
also produces a more attractive shoe. This crimping re
the accompanying drawings in which:
sults in the sides of the vamp being progressively stretched
FIG. 1 is a front elevation of my invention showing
toward the edges thereof, hence providing a fullness in
the
positions of the blade, vamp and clamping shoe prior
20
the vamp tending to force the sides of the Vamp down
to actuation of the apparatus;
wardly with the longitudinal center line assuming a con
FIG. 2 is a vertical section taken along the line 2_2
cave upwardly position.
of
FIG. l;
Vamp crimpers built under the teachings of the prior
FIG. 3 is a front elevation in partial cross-section along
art suffered from several serious defects, however. One 25 the line 3_3 of FIG. 2 showing the blade, vamp and
such defect is that the center line of the vamp, which is
clamping shoe in crimping position;
not stretched in the crimping process, tends to buckle or
FIG. 4 is a plan view of a vamp prior to stretching
ride up on itself during the stretching of the side por
showing the approximate areas where stretching occurs;
tions. This results from the natural tendency of the
FIG. 5 is a side elevation of a vamp after stretching;
leather to squeeze together at those portions of itself 30
FIG. 6 is a section taken on the line 6_6 of FIG. 5;
which are structurally opposed to the areas being
FIG. 7 is a section taken on the line 7_7 of FIG. 5;
stretched. As it is common to crimp the vamp by forc
FIG. 8 is a view in perspective showing the blade, jaws
ing it between curved jaws by means of a blade engag
and part of a vamp prior to stretching, the vamp having
ing the vamp along its center line, the center line is the
a =set of longitudinal reference lines;
portion of the vamp which tends to buckle and ride up
on itself. Where this occurs a very unsightly series of
wrinkles are the usual result.
35
yAnother defect in vamp crimpers heretofore made has
been their inability to receive more than one thickness
of leather without harming the thickened portion. This 40
has meant that the vamp per se had to be crimped before
the usual lining and other related parts of the upper could
be attached to the Vamp. This sequence of operations
makes the attachment of the other parts to the vamp
FIG. 9 is a partially cut-away side viewA showing the
i vamp in FIG. 8 in fully depressed position between the
jaws; and
FIG. l0 is a fragmentary portion of FIG. 1 showing in
addition means for actuating the blade.
'
» Having reference to the drawings for a more particular
description, I mount two opposed jaw assemblies on hori
zontal arm segments 20 carried by a suitable standard
(not shown). The jaw assemblies are identical in con
struction, and each comprises a metal base 22 having two
more difficult, as it is necessary to attach them to curved 45 upstanding frame members 24, 26. The upper portions of
surfaces rather than to a flat piece of leather.
the frame members 24, 26 are rounded from front to rear
Accordingly, one object of my invention is to provide
a vamp crimper which properly stretches the vamp with
to provide a smooth surface having no sharp edges. Be
out producing wrinkles caused by buckling or riding up
positioned dimensioned slightly larger than the frame
members 24, 26 to provide supporting surfaces for'the
laterally extending parts of the vamp.
Slidably mounted through the frame members 24, 2‘6
tween the frame members 24, 26 a wooden block 28 is
along the center line.
50
Another object of my invention is to provide a vamp
crimper which will crimp a vamp which has other upper
portions and lining material attached thereto, such as a
and block 28 is a horizontal shaft 30. Attached to the
tip, a moccasin seam, a decorative effect added to or over
inner portion of the shaft 30 is an electrically actuated
lying the toe portion, a saddle, a tongue lining or por 55 heater '32 having substantially the ysame dimensions as the
tions of the quarters or lace stays added to or overlying
frame members 24, 26. Each heater 32 abuts and heats
the Ivamp portion over the instep.
its respective crimping jaw 34 which is secured to the
In the practice of my invention, in a preferred embodi
inner end of shaft 30. Each crimping jaw 34 is a steel
ment thereof, I utilize a vamp crimper made along the
usual lines of construction. Such device comprises a pair 60 plate having a rounded top edge 36 over which the leather
is drawn during operation of the apparatus. Each crimp
of laterally adjustable heated jaws mounted on a base
ing jaw ‘34 extends somewhat beyond the heater 32 on all
with a crimping blade disposed over and between the
sides. It is to be noted that the heater 32 and associated
jaws for downward travel therebetween. The blade is
crimping jaw 34 are Slidably mounted relative to the base
provided with a special edge for engaging the leather
vamp. The blade edge is constructed with a thicker seg 65 22 of the jaw assembly whereby the opposed crimping
jaw 34 may be moved apart or together by proper move
ment in the middle and with thinner segments toward the
_ ment of the horizontal shafts 30.
ends. This construction permits the jaws to receive a
The two crimping jaws preferably include oppositely
vamp with the other attached elements. The blade, being
disposed matching pockets ‘35, which are areas cut away
thinner toward its ends, forms pockets in cooperation with
the jaws which permit the presence of the additional thick 70 on the facing sides of the jaws to provide room to receive
nesses of material without adversely affecting the crimp
_ ing operation. Additionally, I have found it desirable to
thickened parts of the upper adjacent the part being
crimped during the crimping operation. Pockets 35, if
3
3,048,864
used, cooperate with corresponding pockets in the crimp
ing blade, which will be described hereinafter.
In the preferred form of blade used in crimping men’s
shoes, the horizontal dimension of the blade between the
In order that the jaws 34 may function most eñ‘iciently,
pockets 55 is about 2% to 3 inches. This is suñicient
to stretch the vamp properly over that area running from
the rear of the toes to the instep.
a .set of coiled springs 38 are mounted parallel to the
horizontal shaft 30, abutting the heater casing 32 at one
end and the outer frame member 24 at the other end.
Although the configuration of the blade 52 of my in
vention permits the crimping of uppers ready for last
ing, an operation not practically possible under the teach
ings of the prior art, it should be noted that I also pro
The springs pass through aligned openings formed in the
inner frame member 26 and block 28. In practice, six
springs 3S are employed for each jaw ‘34,-and they are
positioned under compression to urge the heaters 32 and
associated jaws 34 toward each other.
vide means for preventing the upper from buckling or
Wrinkling along the longitudinal center line of the vamp,
The force exerted by the springs 3‘8 may be controlled
thereby eliminating a defect often produced by prior art
by means of a cam member 40v which is rotatably mounted
vamp crimpers.
on the horizontal shaft 30 exterior of the outer frame
member 24. A pin 42 is positioned on the outer face of
the outer frame member 24 and engages an inclined an
In order to prevent such buckling of the upper, I pro
vide a clamping shoe 56 located »between the jaws 34.
The clamping shoe 56 is provided with an engagement
face 59 which is convex in shape and is dimensioned to
correspond with the concave face 54 of the blade 52.
It is to be noted that the clamping shoe 56 extends
nular cam face 44 on the cam member 40'. The cam mem
ber 40 is held against the outer face of the frame mem
ber 24, and simultaneously means for gross adjustment of
the spacing of the jaws 34 is provided by a threaded ad 20 longitudinally between the jaws 34 less than the full
justing nut 46 which engages the threaded exterior end of
length of the blade 52 but more than the length of the
the horizontal shaft 30. A lock nut assembly indicated
»center section S4 alone.
generally at 48 and provided with a handle 50 is em
The clamping shoe 56 is positioned between the jaws
ployed to lock the adjusting nut 46 when proper relative
34 on a vertically movable support memlber S8 which
spacing of the jaws ‘34 is achieved. Adjustment of the cam 25 has a rounded upper end 60‘ which iits into a suitable
members V4t) may be made to vary the force required to
opening indicated generally at 62 in the bottom of the
spread the jaws 34.
Positioned directly above the opening between the jaws
clamping shoe 56. The clamping shoe 56 and slidable
34 is a crimping blade 52. The blade S2 is movable ver
tically to descend between the jaws 34 by means of a suit
providing the opening 62 in the clamping shoe S6 slightly
able pneu-.rnatic or hydraulic cylinder assembly shown in
FIG. 10 in which the cylinder 51 has a piston and piston
support member 58 are joined by a horizontal pin 64.
By
30 larger than the upper end of support member 58, the
clamping shoe 56 is enabled to move slightly relative
to the support member 5S to more easily adjust to slight
rod 53 connected to the blade 52. The piston moves up
diiterences in positioning of the upper in the apparatus.
or down in conventional manner under the control of the
The slidable support member 58 has a laterally extend
operator as fluid is introduced to the upper or lower ends 3 Ul ing boss 63 into which is screwed the threaded upper end
of the cylinder through appropriate supply pipes.
of piston rod 66 which extends vertically from a piston
in a suitable pneumatic cylinder 63 carried by bracket
7b positioned beneath the horizontal arm segments 20.
If desired, a strong compression spring might be substi
ported and actuated in its vertical movement by a rear 40 tuted for the pneumatic cylinder 68 to urge the clamping
wardly extending and pivoted arm of such length that the
shoe upwardly as required. The bracket 70 is attached
movement of the blade follows substantially a straight
to the horizontal arm segments 20 by suitable bolts 72.
line as the crimping operation is performed.
The support member 58 is held in proper operating posi
The blade 52 is of slightly less longitudinal dimension
tion by vertical guide members 74, 76 which are attached
than the jaws 34 and has a concave engagement face 54
to the bracket 70. The guide member 74 is grooved to
which is dimensioned to correspond with the convex con
receive
the support member 58, and the guide member
figuration of the crimping jaws 34. The engagement face
76 is provided with a gib 78 which is .grooved to re
54 `>is rounded to prevent damage to the upper during
ceive the support member 58. Adjustment screws 80 are
crimping.
Other conventional means for actuating the blade 52
through its up and down movement may be used. For
example, according to the prior art, the blade may be sup
'Ihe blade 52, which is preferably about 5%; inch thick,
is further provided with pockets or indentations S5 formed
by partially cutting away the ends thereof on both sides
provided for the proper positioning of the gib 7S.
50
The operation of my apparatus is as follows:
Begin
ning with the blade S2 in its uppermost position, air is
supplied through pipe 8,1 to the pneumatic cylinder 68
whereby the pockets of the end sections are reduced to a
under suiiicient pressure to create `adequate resistance to
thickness of `about 1A inch. The blade pockets are located
the downward
of the clamping shoe 56. In
so as to cooperate with the jaw pockets 35 to provide 55 practice, i-t has movement
been found that with a one-square-inch
extra space for thickened upper parts. The thinning of
piston eighty pounds per square inch is a suitable pressure
the blade 52 at its ends at 55 is carried upward from
for proper operation. As above noted, the same effect
the engagement face 54 to a line 57 which is close to the
may be obtained by spring means, the upper end of which
top faces 36 of the jaws 34 when the blade 52 is at the
would engage the member 58 with the lower end support
bottom of its travel between the jaws 34 (see FIGS. 5 60 ed by the bottom of bracket 70. It is to be noted, as
and 9). By this novel expedient of thinning the ends of
shown in FIGS. 1 and 2, that the clamping shoe 56 is
the blade 52 with respect to the center section and the use
normally positioned slightly above the jaws 34.
of the jaw pockets 35, it is possible to use my vamp
The leather upper or vamp to be crimped is then posi
crimper for the crimping of uppers which already have
tioned on top of the jaws 34 with its longitudinal center
the lining and other portions of the upper sewn in place. 65 line positioned above the clamping shoe 56. FIG. 4
This result is due to the fact that such other parts are
shows a plan View of such a vamp, the shaded areas
located toward the toe and instep- to make the upper
showing
the pytrarn-idally shaped areas in which stretch
thicker toward its ends. Since during the crimping oper
ing is desired. Since the leather is usually quite thin,
ation the upperis positioned longitudinally with respect
to the jaws 34, the thinning of the blade 52 and the provi
sion of the jaw pockets '35 permit the added thickness of
upper material to move into position between the jaws 34
especially in the making of higher quality shoes, and
since the movement of the leather over the jaws 34
would tend lto harm its finish, it is customary in the
art to employ a resilient leather boot, on top 0f which
without harm, while simultaneously the proper stretching
the Vamp is placed. The boot consist-s of a sheet of %4
force is applied by the thicker mid-portion 54 of blade 52
inch thick chrome tanned soft upper leather which rests
to the mid-section of the vamp.
75 directly against the jaws 34. I have found that best re
3,048,864
A
'sults are achieved where uppers of tine leather are to be
stretched if in addition to the boot one to three sheets
of extremely resilient pure gum live rubber j/16 inch thick
are placed between the upper and the boot in a sand
wiched relation.
FIG. 3 -shows the arrangement for
crimping an upper 82 of medium thickness through the
use of two sheets of rubber 84 and a boot S6. It the
upper to be crimped is of thin leather, then an extra
sheet 84 of the pure gum live rubber should be added.
if the upper is of thicker leather, then one of the sheets
S4 is preferably removed. Thus the novel boot herein
disclosed makes it possible, by varying the number of
rubber sheets, to crimp with equal success uppers of
varying thickness.
ln operation, the blade 52 is brought down to engage
the upper, rubber and boot sandwich.
The blade 52 en
t3
I claim:
.
l. A vamp crimper comprising a pair of spaced jaws
in the form of parallel plates having convex curved up
per edges, a depressible clamping shoe between said plates
having a convex curved upper edge which is normally
positioned above the said jaws, a crimping blade posi
tioned above said jaws and clamping shoe, said blade hav
ing a concave curved lower edge of substantially the same
curvature as the upper convex curved edge of said clamp
ing shoe, means for causing the descent of said crimping
blade to iirst clamp a shoe upper and underlying boot be~
tween said blade and said clamping shoe and thereafter
for causing further downward movement of said clamp
ing shoe, shoe upper, boot and blade between said jaws,
whereby the leather of said shoe upper as it is dragged
downwardly by the blade along with said boot over the
curved upper edges of said jaws to a vertical position be
tween said blade and jaws is progressively and symmetri
cally stretched in a direction parallel to the line of clamp
20 ing of said shoe upper between said blade and clamp
gages the upper and presses the several layers against the
clamping shoe 56. As there is a resistance of eighty
pounds provided by the clamping shoe 56, a iirm en
gagement is produced. The blade 52 is forced ‘down
ing shoe.
between the jaws 34 to the desired depth, as shown in
2. A vamp crimping machine comprising a pair of
FlG. 3, by overcoming the pneumatic or spring resistance
spaced jaws having their opposed faces parallel, the upper
of the clamping shoe 56. This causes the upper 82 and
edges of said jaws being convex and parallel, a _clamping
the sheets Se and 86 to be progressively drawn downward
over the top convex edges of the jaws 34 while at the 25 shoe between said jaws, said clamping shoe supported by
resilient means permitting said clamping shoe to be de
same time being held smoothly between the blade 52
pressed between said jaws, the upper edge of said clamp
and the jaws 34. This action crimps or stretches the u-p
ing shoe being convex and normally above the upper
per progressively toward the sides thereof.
edges of said jaws, a crimping blade located above said
The stretching of the upper or vamp is shown diagram
matically in FIGS. 8 and 9. HG. 8 shows a fragment 30 clamping shoe and parallel to said jaws, the bottom edge
of said blade being concave and of substantially the same
of an upper 82. resting on the jaws 34 with the blade 52
curvature as the upper edge of said clamping shoe, means
in position above them. For clarity in these figures,
for causing the descent of said blade toward said clamp
the boot has been omitted. In practice, the boot is al
ing shoe whereby a sheet of material to be stretched and
ways used. A series of equal longitudinal lines A--A’,
an underlying boot may be iirst clamped between said
B--B’, C-C', D-D’ and E-E’ are shown in which
clamping shoe and blade, and thereafter for causing fur
the line A-A’ is the longitudinal center line of the upper.
ther downward movement of said blade whereby the ma
A2, B2, C2, D2 and E2 represent the mid-points of the
terial and boot will then be drawn downwardly over the
several lines. The lines A-A’ also represents the nar
curved upper edges of said jaws to a flat position between
row longitudinal area along‘which the upper 82 is firmly
clamped between the blade 52 and the clamping shoe 56. 40 said jaws, thereby to longitudinally stretch the said sheet
of material on both sides of the line of clamping between
FlG. 9, in which the near jaw 34 has been removed, shows
said clamping shoe and said blade.
what happens to the upper when the blade 52 has been
3. A machine for stretching a stretchable sheet of ma
forced down between the jaws 34, driving the shoe 56
terial on both sides of a selected line, said machine com
downwardly and dragging the leather over the convex
45 prising a pair of jaws in the form of a pair of spaced
jaws.
vertical plates with their facing sides parallel, the upper
It will now be apparent to one skilled in the art that
as the upper is drawn over and between the jaws and is
edges of said jaws being identically curved convexly,
spring means permitting said plates to spread apart upon
the application of suñ'icient spreading force, a clamping
shoe 56 and from buckling along its sides by the pressure
of jaws 34, the leather must stretch progressively as it 50 shoe positioned between said jaws, said clamping shoe
being of less longitudinal dimension than said jaws, the
descends. FIG. 9 shows this stretching in the area above
upper edge of said clamping shoe being convex and of
the clamping shoe 56, where it is most pronounced. The
prevented from buckling along its center line by clamping
line A-A’ in FIG. 9 is the same length that it was at
the start in FIG. 8, as this area of the upper is held
substantially the same curvature as the curvature of the
top edges of said jaws, the upper edge of said clampingr
iirrnly between the blade 52 and the clamping shoe 56. 55 shoe normally being positioned above the upper edges of
said jaws, resilient supporting means for said clamping
The line B-B’, which was originally the same length
shoe whereby said clamping shoe may -be forced down
as the line A-A' in FIG. 8, is now slightly longer
wardly between said jaws, a crimping blade located above
in FIG. 9. Similarly, the distances along lines C»-C’,
said clamping jaws and of less thickness than the space
D-D’ and E-E’, originally equal in FIG. 8, have pro
gressively increased, as in FIG. 9, as the leather has been 60 between said jaws, said blade being longer than said
clamping shoe and having a concave lower edge of the
stretched.
While the blade 52 is in lowermost position, as shown
same curvature as said clamping shoe, the lower end por
in FIGS. 3 and 9‘, the heat radiated from the heater 32
tions of said blade being of reduced thickness as compared
through the jaws 34 causes the leather to “set” in its
with the thickness of that portion of said blade immedi
stretched or crimped form. When the blade SZ is with 65 ately above said clamping shoe, and means for causing
drawn upwardly, the clamping shoe 56 simultaneously re
controlled downward movement of said blade, whereby
turns to its uppermost position, ejecting the stretched or
when a shoe upper is placed on said clamping shoe said
crimped upper and the underlying protective sheets. The
blade may be caused to descend to clamp said upper be
upper, after being stretched in this manner, is in proper
tween said shoe and blade, and upon further downward
70
shape for easier lasting, as is shown in FIGS. S, 6 and 7.
movement of said blade and clamping shoe with the shoe
The apparatus is then ready for another operating cycle.
upper clamped therebetween the said upper will be pro
It is my intention to claim all modifications and changes
gressively dragged over the convex upper edges of said
of the preferred embodiment of my invention herein
jaws and progressively stretched in a longitudinal direc
chosen for purposes of disclosure which do not constitute
75 tion, the said portions of said blade that are of reduced
departures from the spirit and scope of the invention.
3,048,864
thickness, when moved down to a position between said
jaws, providing space between said jaws and blade for
thicker portions of said shoe upper.
4. Apparatus for crimping a shoe upper comprising a
base, a pair of heated opposed jaws each having a substan
tially convex top face mounted on said base, a convex
clamping shoe, resilient means normally supporting said
clamping shoe between said jaws at a position slightly
higher than the top of said jaws, a vertically movable blade
positioned over said clamping shoe and dimensioned to ñt
between said jars, a substantially concave Contact edge on
said blade of the same curvature las said jaws and said
clamping shoe, and means for moving said blade down
wardly to cause said blade to engage a leather upper
placed over the said convex top »faces of said jaws and to
clamp said leather against said shoe, said last mentioned
means thereafter arranged to move said blade, leather and
shoe downwardly between said jaws stretching said leather
8
7. In a vamp crimper, a blade including a lower engage
ment edge having a substantially concave configuration, a
center segment of said blade thicker than the thinner end
segments thereof, said thinner segments of said blade
adapted to receive thicker portions of said vamp.
8. A crimping blade for use in a vamp crimper having
oppositely disposed jaws, said blade comprising `a vertically
disposed rigid sheet of metal about 3A; inch thick, the lower
edge of said blade being concave downwardly, the two
lower ends of said blade being of reduced thickness in the
order of abou 1A inch to leave a center section about 3
inches long of unreduced thickness at the bottom of said
blade, the vertical dimension of the areas of reduced thick
ness being at least substantially equal to the distance said
blade is to descend between the said jaws.
9. A vamp crimper comprising a pair of spaced jaws
separable under pressure, a crimping blade Valigned with a
resiliently mounted clamping shoe which is positioned be
upper on both sides of the line of clamping between said
tween said jaws, the bottom of said blade being concave
blade and shoe.
20 and the tops of said jaws and shoe being convex, said blade
5. Apparatus as defined in claim 4, said jaws having ophaving substantially the same curvature as the tops of said
positely disposed pockets vertically aligned with the end of
jaws and shoe, and means for first moving said blade to~
said blade.
ward said shoe to clamp a piece of leather therebetween
6. Vamp crimping apparatus comprising a base, a blade
mounted on said base for up and down travel relative
thereto, a concave lower edge on said blade having a
center section thicker than the end sections thereof, a pair
of opposed crimping jaws disposed below said blade posi
tioned to allow said blade to pass veitically between them,
means lfor heating said jaws, convex top surfaces on said
jaws of the same curvature as said blade, a clamping shoe
having a convex -top surface of the saine curvature as the
lower edge of said blade, said shoe positioned between
said jaws in the line of travel of said blade, resilient sup
porting means positioningsaid clamping >shoe top surface
normally slightly above the said top faces of said jaws, and
means for driving said blade downwardly between said
jaws whereby an upper positioned on top of said jaws is
engaged by said blade and carried downwardly thereby
and for thereafter moving said blade, shoe and leather
clamped therebetween to a position between said jaws, said
jaws maintaining sufficient pressure on the leather against
the faces of said blade to stretch said leather smoothly and
progressively as it is dragged over the tops of said jaws.
l0. A vamp crimping machine comprising a pair of
spaced jaws, a resiliently mounted clamping shoe between
said jaws, a crimping blade located above said shoe, and
means for moving said blade downwardly to clamp ma
terial between said blade and shoe, and for thereafter mov
ing said material and shoe downwardly between said jaws,
one end of said blade being of reduced thickness and said
jaws 4having oppositely facing pockets vertically aligned
with the reduced thickness portion of said blade.
References Cited in the tile of this patent
being progressively stretched as i-t passes over the edge 40
of said jaws, and being‘held in ñrm engagement with said
blade by the upward pressure exerted by said clamping
shoe thereby preventing said upper from buckling along
the .line of contact with said blade.
UNITED STATES PATENTS
5,412
27,561
276,408
White ________________ __ Jan. l2, 1848
Nolen et al ____________ __ Mar. 20, 1860
Holmes ______________ ~_ Apr. 24, 1883
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