Technical Field
[0001] The present invention relates to the technical sector concerning sewing vamps to
soles of shoes for realising footwear.
Background Art
[0002] The prior art comprises machines which realise a sewing of an open vamp onto a moulded
sole made of a synthetic material, for example polyurethane. These machines are obtained
by opportunely tooling a machine for sewing with a curved needle, in which the needle
is borne at the free end of an arm, keyed radially on a longitudinally-arranged shaft
in the head of the machine itself.
[0003] The shaft is designed to be activated with an alternating oscillating motion, such
as to move the needle between two extreme positions, along a curved trajectory which
is concentric of the radius of curvature of the needle.
[0004] The machine is provided with suitable guide and support means destined to define
the correct vertical positioning of the sole during sewing.
[0005] In the outward oscillation the needle passes first through the lower edge of the
vamp, and then the sole, and exits laterally of the latter, then entering a rotary-hook
device, commonly known as a crotchet, which is designed to cooperate with the needle
in order to form the stitch.
[0006] In suitable phase-relation with the outward oscillation of the needle, a holding
member is activated such as to press the sole in the opposite direction to the needle
advancement and thus oppose the thrust of the needle.
[0007] With the needle engaged in the vamp and the sole the longitudinal shaft is axially
translated in synchrony with the crochet by an amount which is equal to predefined
stitching step, thus determining the advancement of the material to be sewn.
[0008] The return oscillation of the needle is then commanded, which determines the disengagement
of the needle from the material and enables an opposite translation to be performed,
of a same extension, of the shaft-needle-crochet group, in order to bring the group
back into the initial position.
[0009] In setting-up the above-described machine, the head is arranged inclined with respect
to the vertical, such that the portion of the circular trajectory described by the
needle at the sewing zone is appropriated orientated such as to facilitate the entry
of the needle into the vamp and the exit thereof from the sole.
[0010] The shoe obtained, known in the footwear sector as IDEAL, exhibits two externally-visible
stitch lines, one along the lower edge of the vamp and the other on the side of the
sole.
[0011] Also known are shoes, entirely for females, known as BALLERINA (ballerina pumps),
which are constituted by an open vamp of small dimensions, joined to a thin sole often
without a heel and preferably made of leather.
[0012] In the best realisations of these shoes, the sole is prepared with a small step in
the relative perimeter edge, and with an incision being made that starting from the
upper surface of the sole penetrates obliquely into the thickness thereof, in the
direction of the perimeter edge, and extends along a closed-ring trajectory which
follows, at a more-or-less constant distance, the plan profile of the sole.
[0013] The vamp is turned through and the external side of the lower surface is glued at
the position of the step.
[0014] The joint is then stabilised with a stitching that goes from the internal end of
the incision up to the step, and involves the pre-glued lower edge of the vamp. Once
the sewing operating has been concluded, the vamp is newly turned through and the
stitching is invisible both externally and internally of the shoe.
[0015] The stitching described above is realised either manually or using machines constructed
expressly for this operation; in the first case the drawbacks are related to the slowness
of execution and the need for specialised operatives, while in the second case a considerable
investment is required in a machine totally lacking in versatility, which can risk
lying idle for long or short periods according to market demand.
[0016] The curved-needle machine, with the tooling described for IDEAL shoes is not suitable
for realising the stitching in BALLERINA shoes.
[0017] FR 513.102 discloses a machine for sewing a vany to a sole of a shoe which serves as basis for
claim 1.
Summary of the Intention
[0018] The aim of the present invention is therefore to provide a machine for sewing a vamp
to a shoe sole which exploits the intrinsic characteristics of curved-needle machines
and is equipped such as to enable sewing BALLERINA type shoes.
[0019] A further aim of the invention consists in providing a machine which performs the
stitching starting from a semi-finished workpiece (vamp + sole) in exactly the same
way as known systems.
[0020] A still further aim of the invention is to provide a machine which is able to sew
a slim sole to a vamp, where the sole is either leather or synthetic, in order to
obtain shoes that are different to BALLERINA models.
[0021] A further aim of the invention relates to the desire to provide a machine in which
the specific tooling for sewing BALEERINA shoes can be rapidly demounted so that the
machine can be temporarily adapted to other operations.
Brief description of the Drawings.
[0022] The characteristics of the invention will more fully emerge from the following description,
of a preferred embodiment of the sewing machine of the invention, in accordance with
what is set out in the claims and with the aid of the accompanying figures of the
drawings, in which:
figure 1 is an exploded perspective view of a vamp and a sole of a shoe of the BALLERINA
type;
figure 2 is a large-scale illustration of a partial section of the sole along plane
II-II of figure 1;
figure 3 is a partial front view of the machine in a non-operative mode;
figure 4 is a similar view to that of figure 3, with the machine in a first operating
stage on a shoe;
figure 5 is a large-scale view from the entry side of the needle, illustrating the
stitching organs in the first operating stage of figure 4;
figure 6 is a frontal view, partially sectioned, of the stitching zone, with the organs
in the first stage of figures 4 and 5;
figure 7 is a similar view to that of figure 5, with the organs in a second operating
stage;
figure 8 is a front view, partially sectioned of the sewing zone, with the organs
in the second stage illustrated in figure 7;
figure 9 is a similar view to that of figures 5 and 7, with the organs in a third
operating stage;
figure 10 is a view from the exit side of the needle, relating to the stage illustrated
in figure 9;
figure 11 is a partial section of the sole and the vamp after stitching;
figure 12 is a perspective view of a BALLERINA shoe when completed.
Description of Preferred Embodiments of the Invention.
[0023] With reference to the figures of the drawings, M denotes the sewing machine of the
invention in its entirety.
[0024] The machine M, in known ways, comprises a head 1 in which the movement organs for
activating the sewing organs are housed.
[0025] A longitudinal shaft (not illustrated in detail) enters among the movement organs,
which shaft projects frontally from the head 1 and bears keyed thereto a radial arm
3, at a free end of which a needle 4 is fixed and develops in an arc of circumference,
a centre of which coincides with the axis of the shaft 2 (see in particular figure
4).
[0026] The longitudinal shaft 2 is destined to be activated alternatingly oscillatingly,
such as to move the needle 4 between two end positions, respectively a retracted position
R and an advanced position A, along a curved trajectory concentric with the radius
of curvature of the needle 4 and arranged on a vertical plane.
[0027] In the outward run, between the retracted position R and the advanced position A,
the needle 4 is destined to encounter and pass beyond the material to be stitched,
supported and positioned by special organs, as will be described in more detail herein
below.
[0028] When the needle 4 is in the advanced position A, the point thereof is internal of
a rotating-hook 5 device, known as a crotchet, with which it cooperates to realise
the sewing stitches with two knotted threads.
[0029] When the operator releases the start pedal of the machine M, a known device intervenes
to cause the automatic halting thereof, with the needle 4 in the retracted position
R.
[0030] A holding member 6 is arranged in the space between the material to be sewn and the
crotchet 5, which holding member 6 is mobile on a parallel plane to the oscillation
plane of the needle 4, which pushes the material in an opposite direction to the advancement
of the needle 4, such as to bear the thrust and facilitate penetration thereof.
[0031] The longitudinal shaft 2 is axially translatable with alternating motion in runs
of predetermined entity, in synchrony with the crotchet 5 and in suitable phase relation
with the oscillation of the needle 4 and with the movement of the holding member 6,
such as to impress on the needle 4 a perpendicular motion with respect to the oscillation
plane thereof, representing a predetermined stitching step.
[0032] In a preferred embodiment, a known device 40 for protecting the needle is associated
to the needle 4; this needle-protecting device 40 is constituted by an oscillating
lever 41 which is concentric to the radial arm 3 and subject to the action of a spring
42.
[0033] The oscillating lever 41 is shaped at a free end thereof such as to partially envelop
the beam of the needle 4 and when the needle is in the retracted position thereof
R the action of the spring 42 maintains the lever 41 at the zone of the point of the
needle 4.
[0034] The lever 41 is destined to oppose any anomalous flexion solicitations which might
occur on the needle 4 during the phase in which it passes through the material; for
this purpose it follows the needle in the outward run thereof towards the advanced
position A, up to when the impact with the material takes place, which halts the run
of the lever 41 while the needle 4 penetrates the material.
[0035] The machine M of the invention is equipped with the following organs:
a spreader foot 10, provided at a lower end of a bearing element 11 having a substantially
vertical development, solidly constrained to the head of the machine M such that the
spreader foot 10 is located on a vertical plane that is parallel to the oscillation
plane of the needle 4, in an intermediate position between the retracted position
R and the advanced position A thereof; the spreader foot 10 exhibiting, in the side
thereof facing the needle 4, a gully 10A which partially envelops the beam of the
needle 4 during the outward run of the needle 4 towards the advanced position A;
an abutting foot 12 fixed inferiorly to the bearing element 11, such as to be in an
opposite position to the spreader foot 10;
a supporting stud 13, having a substantially vertical axis, arranged below the spreader
foot 10 and the abutting foot 12, in a practically central position thereto;
a shaped arm 14, a top of which bears the support stud 13, the shaped arm 14 freely
oscillating with respect to a relative base, according to an axis that coincides with
the axis of the support stud 13.
[0036] The support stud 13 is associated to means for height-adjustment, for example a screw
mechanism, not illustrated in detail.
[0037] In a preferred embodiment, the support stud 13 is born idle on the axis thereof and
exhibits at least a portion 13A of the relative upper element which is obliquely cut,
for reasons that will more fully emerge herein below.
[0038] The machine M, thus equipped, is destined to sew a vamp T to a sole F of a shoe 20
of the BALLERINA type, described in the preamble hereto (figure 12).
[0039] In some machines M destined for sewing particular models and/or formats of shoes
20, the axis of the support stud 13 (and the arm 14), differently from what is illustrated
above, can be inclined towards the spreader foot 10 by an angle of about 15° with
respect to the vertical.
[0040] Similarly to the prior art, the sole F is relatively thin (about 6mm), preferably
made of leather, and, in the illustrated example is without a heel.
[0041] The sole F is prepared by realising a step 21 in the relative perimeter edge 22 and
creating a slit 23 which, starting from the upper surface 24 of the sole F, penetrates
obliquely into the thickness thereof, in the direction of the perimeter edge 22, and
extends along a closed-ring trajectory which follows the plan profile of the sole
F at a practically-constant distance (figures 1 and 2).
[0042] With respect to the normal configuration illustrated in figure 1, the vamp T is turned
(figure 2) and the outside side 25A of the lower edge 25 thereof is glued to the step
21 (figures 6, 8).
[0043] The above-described operating stages realise a semi-finished workpiece S which can
be subjected to the action of the machine M for stabilising, by stitching, the union
between the vamp T and the sole F as is more specifically described herein below.
[0044] The semi-finished workpiece is inserted by suitably orientating the shaped arm 14
and is arranged such that the lower surface 26 of the sole F (i.e. the surface which
when the shoe is finished is destined to contact the ground) rests on the support
stud 13, which is orientated and height-regulated for the purpose, such as to define
an abutment at a predetermined height.
[0045] The semi-finished workpiece S is then translated and rotated horizontally, aiding
the manoeuvre with suitable displacements of the shaped arm 14, up to bringing the
spreader foot 10 to partly insert in the slit 23 such as to distance the adjacent
lips L1, L2 in the zone of the slit 23 which is destined to constitute the start of
the stitching (figures 4, 5 and 6) as well as bringing the abutting foot 12 to laterally
abut the lower edge 25 of the vamp T and the adjacent perimeter edge 22 of the sole
F.
[0046] The action of the spreader foot 10 is facilitated by specially inclining the semi-finished
workpiece S, thanks to the inclined cut of the portion 13A of the support column 13,
which can be orientated in the most favourable position (figures 4, 6).
[0047] At this point it is possible to start the machine, by means of the pedal, in order
to initiate the stitching:
the needle 4 inserts between the opened lips L1, L2 of the slit 23 (figure 7) to pass,
in order through sole F and the lower edge 25 of the vamp T, exiting in a median position
with respect to the height of the step 21; in this movement it is aided by the action
of the holding member 6 (figure 8);
the needle 4 proceeds towards the first advanced position A which brings it internally
of the crotchet 5 (figures 9, 10) and, in phase relation, the synchronous axial translation
of the shaft-needle-crotchet group starts to advance the material to be stitched by
one sewing step (arrow X in figure 9);
at the end of the translation, the needle 4 is made to oscillate towards the retracted
position R to disengage from the material, the operation being facilitated by the
presence of the spreader foot 10, which functions as an abutment;
an opposite axial translation is impressed on the shaft-needle-crochet group, which
returns it to the initial position, ready for a new sewing stitch.
[0048] The operator manually accompanies the semi-finished piece S for the whole ring-trajectory
of the slit 23, displacing the shaped arm 14 into the position which is most appropriate
each time.
[0049] Once the stitching C is completed, and the semifinished workpiece S extracted, the
vamp T is newly turned to return it to its normal configuration, defining the shoe
20 (figure 11, 12).
[0050] The stitching C is invisible from the outside of the shoe 20, as it is hidden by
the folding-over of the vamp T, and also from the inside, as it is covered by the
lips L1, L2 of the slit 23, newly neared to one another (see figures 11 and 12 once
more).
[0051] In a constructional variant of the machine, not illustrated, an actuator, for example
a pneumatic actuator, is combined with the means for height-regulating the support
stud 13, which can sharply lower the stud 13 by a predetermined amount in order to
enable stitching in the zone of the heel should the sole F exhibit a small heel block.
[0052] In the above examples, reference has been made to leather soles, but obviously the
described machine is also able to perform sewing operations on a moulded sole made
of a synthetic material, as long as it has similar shape and dimensions.
[0053] The special characteristics of the machine of the invention clearly emerge from the
above description, which fully attains the set aims, firstly in order to easily obtain
a special stitching, which is a distinguishing sign of a prestige shoe, without using
either specialist operators or specific machinery.
[0054] With reference to BALLERINA shoes, special mention must be made of the fact that
the machine is designed to perform the stitching starting from a semifinished workpiece
(vamp + sole) prepared exactly in the same way to what is required in the prior art,
totally respecting, therefore, the shoe-making traditions and the final quality of
the product obtained.
[0055] Obviously the machine can also be used, with the described tooling, for footwear
not precisely describable as BALLERINA shoes, as long as the footwear is similar in
terms of construction type.
[0056] A further advantageous aspect of the machine is that the operating organs which constitute
the tooling for BALLERINA type shoes 8or the like) can be quickly demounted and replaced
with others, to temporarily convert the machine for other work operations.
[0057] This versatility gives a further advantage, which consists in being able to market,
with perfectly affordable costs, a transformation kit which enables a client already
in possession of a curved-needle machine to convert it for the work operations that
have been mentioned herein.
[0058] It is understood however that all of the above is given by way of non-limiting example,
and therefore any eventual modifications to details thereof, for example in the form
of the operating organs, which might become necessary for technical and/or functional
reasons, are considered to fall within the ambit of protection defined by the following
claims.
1. A machine for sewing a vamp to a sole of a shoe, the vamp (T) being of a type previously
turned and glued, by a respective lower edge (25), to a step (21) fashioned on the
peripheral edge (22) of a sole (F), the sole (F) also affording a slit (23), originating
from an upper surface (24) of the sole (F), penetrating obliquely into the thickness
of the sole (F) in a direction of the peripheral edge (22) and extending along an
annular path following, at a substantially constant distance, a plan profile of the
sole (F), the machine (M) comprising a support stud (13) having a substantially vertical
axis, which is destined to define a lower abutment as well as a support for the lower
surface (26) of the sole (F); a spreader foot (10), provided at a lower end of a bearing
element (11) solidly constrained to the head (1) of the machine (M), and is destined
to be partially inserted in the slit (23) in order to spread adjacent lips (L1, L2)
apart in an area of the slit (23) which is to be sewn; an abutting foot (12), which
is fixed on the lower portion of the bearing element (11), in an opposite position
to the spreader foot (10) and destined to laterally abut the lower edge (25) of the
vamp (T) and the corresponding peripheral edge (22) of the sole (F), in order to define
the horizontal position of the sole (F) in the area of interest as sewing proceeds;
a needle (4), having a shape extending in an arc of circumference, which is made to
oscillate on a vertical plane parallel to the planes where the spreader foot (10)
and the abutting foot (12) lie, between a retracted position (R), to the side thereof,
and an advanced position (A), in which the needle (4) is inserted between the spread
edges (L1, L2) of said slit (23) to pass through, in order, the sole (F) and the lower
edge (25) of the vamp (T), the needle (4) being translatable perpendicularly to the
respective oscillation plane, with reciprocating motion, according to strokes of an
amplitude of a predetermined pitch; a rotating hook device (5), to which a bobbin
of sewing yarn is associated, arranged on a side opposite a side the needle (4) enters,
the device (5) being destined to interact with the needle (4) in order to realize
stitching points (C).
2. The machine according to claim 1, characterized in that on a side thereof facing said needle (4), said spreader foot (10) is provided with
a gully (10A) partially enveloping the shaft of the needle (4) during the forward
stroke towards the advanced position (A).
3. The machine according to claim 1, characterized in that said supporting stud (13) is arranged at a top of a shaped arm (14) which freely
oscillates with respect to a respective base, according to an axis coinciding with
an axis of said stud (13).
4. The machine according to claim 1 or 3, characterized in that the upper end of said supporting stud (13) is provided with at least an obliquely
cut portion (13A).
5. The machine according to claim 1 or 3, characterized in that the axis of the supporting stud (13) and the associated shaped arm (14) slopes towards
the spreader foot (10) by an inclination angle of 15° with respect to the vertical
direction.
6. The machine according to claim 1 or 3 or 4 or 5, characterized in that said supporting stud (13) is borne idle on its axis.
7. The machine according to claim 1 or 3 or 4 or 5, characterized in that said supporting stud (13) is associated to means for height adjustment thereof.
8. The machine according to claim 7, characterized in that said means for height adjustment are of a screw type.
9. Machine according to claim 7, characterized in that to said means for height adjustment are combined actuator means able to rapidly lower
said supporting stud (13) to a prefixed height, in phase relation with a stitching
sewing of a heel area in a sole (F) which exhibits a small heel.
1. Maschine zum Annähen eines Oberleders an eine Schuhsohle, wobei das Oberleder (T)
von der Art ist, die zunächst umgedreht und mit einem entsprechenden unteren Rand
(25) an eine Abstufung (21) angeklebt wird, die an dem umlaufenden Außenrand (22)
einer Sohle (F) ausgebildet ist, wobei die Sohle (F) ferner einen Riss (23) aufweist,
der ausgehend von einer oberen Oberfläche (24) der Sohle (F) und zum umlaufenden Außenrand
(22) hin schräg in die Dicke der Sohle (F) eindringt und entlang eines ringförmigen
Weges verläuft, der in einem im Wesentlichen konstanten Abstand dem Grundrissprofil
der Sohle (F) folgt, wobei die Maschine (M) Folgendes beinhaltet: einen Auflagebolzen
(13) mit einer im Wesentlichen vertikalen Achse, der sowohl als unterer Anschlag als
auch als Auflage für die untere Oberfläche (26) der Sohle (F) dient; ein Aufspreizfüßchen
(10), das an dem unteren Ende eines tragenden Elementes (11) ausgebildet ist, das
fest mit dem Kopf (1) der Maschine (M) verbunden ist, und das dazu bestimmt ist, teilweise
in den Riss (23) eingeführt zu werden, um jeweils benachbarte Lippen (L1, L2) in dem
zu nähenden Bereich des Risses (23) auseinander zu spreizen; ein Anschlagfüßchen (12),
das am unteren Abschnitt des tragenden Elementes (11) in einer dem Aufspreizfüßchen
(10) gegenüberliegenden Position befestigt ist und dazu bestimmt ist, einen seitlichen
Anschlag für den unteren Rand (25) des Oberleders (T) und den entsprechenden umlaufenden
Außenrand (22) der Sohle (F) zu bilden, um die horizontale Position der Sohle (F)
in dem jeweils vom Nähvorgang betroffenen Bereich zu definieren; eine Nadel (4), die
sich kreisbogenförmig erstreckt und die in einer vertikalen Ebene, die parallel zu
den Lageebenen des Aufspreizfüßchens (10) und des Anschlagfüßchens (12) ist, in eine
Schwingbewegung versetzt wird zwischen einer zurückgezogenen Position (R) an deren
Seite und einer vorgerückten Position (A), in der die Nadel (4) zwischen den auseinandergespreizten
Rändern (L1, L2) des Risses (23) eingeführt ist, um der Reihe nach die Sohle (F) und
den unteren Rand (25) des Oberleders (T) zu durchstechen, wobei die Nadel (4) lotrecht
zu der entsprechenden Schwingungsebene Hin- und Herbewegungen ausführen kann, deren
Ausschlagweite einem vorgegebenen Schritt entspricht; eine drehende Hakenvorrichtung
(5), mit der eine Spule Nähgarn verbunden ist, die auf einer Seite gegenüber der Seite,
auf der die Nadel (4) eintritt, angeordnet ist, wobei diese Vorrichtung (5) dazu bestimmt
ist, mit der Nadel (4) in Wechselwirkung zu treten, um die Nahtstiche (C) zu erzeugen.
2. Maschine nach Anspruch 1, dadurch gekennzeichnet, dass das Aufspreizfüßchen (10) auf einer Seite davon, die der Nadel (4) zugewandt ist,
eine Auskehlung (10A) aufweist, die den Schaft der Nadel (4) während der Vorwärtsbewegung
in die vorgerückte Position (A) teilweise umgibt.
3. Maschine nach Anspruch 1, dadurch gekennzeichnet, dass der Auflagebolzen (13) an der Oberseite eines geformten Arms (14) angeordnet ist,
der relativ zu einer entsprechenden Basis frei entlang einer Achse schwingen kann,
die mit der Achse des Bolzens (13) übereinstimmt.
4. Maschine nach Anspruch 1 oder 3, dadurch gekennzeichnet, dass das obere Ende des Auflagebolzens (13) zumindest einen schräg zugeschnittenen Abschnitt
(13A) aufweist.
5. Maschine nach Anspruch 1 oder 3, dadurch gekennzeichnet, dass die Achse des Auflagebolzens (13) und der damit verbundene geformte Arm (14) ein
Gefälle zu dem Aufspreizfüßchen (10) hin aufweisen, mit einem Neigungswinkel von 15°
bezogen auf die Vertikale.
6. Maschine nach Anspruch 1 oder 3 oder 4 oder 5, dadurch gekennzeichnet, dass der Auflagebolzen (13) antriebslos auf seiner Achse gelagert ist.
7. Maschine nach Anspruch 1 oder 3 oder 4 oder 5, dadurch gekennzeichnet, dass der Auflagebolzen (13) mit Mitteln für seine Höhenverstellung verbunden ist.
8. Maschine nach Anspruch 7, dadurch gekennzeichnet, dass die Mittel zur Höhenverstellung aus Schrauben bestehen.
9. Maschine nach Anspruch 7, dadurch gekennzeichnet, dass mit den Mitteln zur Höhenverstellung Betätigungsmittel verbunden sind, die den Auflagebolzen
(13) schnell um eine vorbestimmte Höhe absenken können, und zwar in Phasenbeziehung
zum Nähen eines Absatzbereiches an einer Sohle (F) die einen kleinen Absatz aufweist.
1. Une machine pour coudre une claque à une semelle de chaussure, la claque (T) étant
d'un type préalablement retournée et collée, au niveau d'un bord inférieur (25) respectif,
à un degré (21) réalisé sur le bord périphérique (22) d'une semelle (F), ladite semelle
(F) présentant aussi une fente (23), partant d'une surface supérieure (24) de la semelle
(F), pénétrant obliquement dans l'épaisseur de la semelle (F) en direction du bord
périphérique (22) et s'étendant le long d'un parcours annulaire qui suit, à une distance
essentiellement constante, un profil en plan de la semelle (F), la machine (M) comprenant
un plot de support (13) ayant un axe essentiellement vertical, qui est destiné à définir
une butée inférieure ainsi qu'un support pour la surface inférieure (26) de la semelle
(F) ; un pied élargisseur (10), prévu au niveau d'une extrémité inférieure d'un élément
porteur (11) solidement assujetti à la tête (1) de la machine (M), et destiné à être
partiellement introduit dans la fente (23) afin d'élargir des lèvres adjacentes (L1,
L2) dans une zone de la fente (23) à coudre ; un pied de mise en butée (12), qui est
fixé sur la partie inférieure de l'élément porteur (11), dans une position opposée
par rapport audit pied élargisseur (10), et destiné à servir de butée latérale au
bord inférieur (25) de la claque (T) et au bord périphérique (22) correspondant de
la semelle (F), de manière à définir la position horizontale de la semelle (F) dans
la zone concernée par la couture ; une aiguille (4), ayant une forme se développant
en arc de cercle, qui est entraînée à osciller sur un plan vertical parallèle aux
plans d'appartenance du pied élargisseur (10) et du pied de mise en butée (12), entre
une position rentrée (R), à côté de ceux-ci, et une position avancée (A), dans laquelle
l'aiguille (4) est introduite entre les bords (L1, L2) élargis de ladite fente (23)
pour passer au travers, dans l'ordre, de la semelle (F) et du bord inférieur (25)
de la claque (T), l'aiguille (4) pouvant être translatée perpendiculairement au plan
d'oscillation respectif, par un mouvement de va-et-vient, selon des courses ayant
une amplitude de pas prédéfini ; un dispositif à crochet rotatif (5), auquel une bobine
de fil à coudre est associée, disposé sur un côté opposé à un côté d'entrée de l'aiguille
(4), le dispositif (5) étant destiné à interagir avec l'aiguille (4) afin d'effectuer
des points de couture (C).
2. La machine selon la revendication 1, caractérisée en ce que, sur un côté faisant face à ladite aiguille (4), ledit pied élargisseur (10) est
doté d'une gorge (10A) enveloppant partiellement la tige de l'aiguille (4) durant
la course en avant vers la position avancée (A).
3. La machine selon la revendication 1, caractérisée en ce que ledit plot de support (13) est disposé au niveau d'une partie supérieure d'un bras
profilé (14) qui oscille librement par rapport à une base respective, selon un axe
qui coïncide avec un axe dudit plot (13).
4. La machine selon la revendication 1 ou 3, caractérisée en ce que l'extrémité supérieure dudit plot de support (13) présente au moins une portion (13A)
coupée obliquement.
5. La machine selon la revendication 1 ou 3, caractérisée en ce que l'axe du plot de support (13) et du bras profilé (14) associé descend vers le pied
élargisseur (10) selon un angle d'inclinaison de 15° par rapport à la direction verticale.
6. La machine selon la revendication 1 ou 3 ou 4 ou 5, caractérisée en ce que ledit plot de support (13) est porté libre sur son axe.
7. La machine selon la revendication 1 ou 3 ou 4 ou 5, caractérisée en ce que ledit plot de support (13) est associé à des moyens de réglage de sa hauteur.
8. La machine selon la revendication 7, caractérisée en ce que lesdits moyens de réglage de la hauteur sont du type à vis.
9. La machine selon la revendication 7, caractérisée en ce que lesdits moyens de réglage de la hauteur sont associés à des moyens actionneurs destinés
à abaisser rapidement ledit plot de support (13) à une hauteur prédéfinie, en relation
de phase avec une couture d'une zone du talon dans une semelle (F) qui présente un
petit talon.