[0001] The present invention relates to a machine for preassembling and assembling an upper
on a shoe-making last in accordance with the preamble of Claim 1.
[0002] In the footwear processing sector, machines are known that automatically perform
the various processing operations. In general terms, said processing operations comprise:
arranging the upper on the shoe-making last after an insole has previously been associated
with the sole of the last, gripping the edges of the upper by means of a multiplicity
of grippers mounted around the last, stretching the upper on the last by means of
a relative displacement between grippers and last, blocking the upper on the last
by means of pressure members, applying an adhesive to the edge of the insole, gradually
easing the grip of the grippers on the upper and turning the edge of the upper over
the edge of the insole, resulting in the adhesive bonding of the edge of the upper
to the insole.
[0003] In order for the assembly of the upper on the insole to be performed correctly, the
grippers have to be positioned around the last in a manner such that their gripping
tips, or more specifically the segments that define the respective gripping portions
of the tensioning grippers, are mutually aligned at a predetermined distance from
the last, reproducing the profile of the latter and exercising a uniform traction
along the entire edge of the upper.
[0004] The tensioning grippers comprise a central gripper positioned in alignment with the
front part of the shoe-making last and two respective opposing pluralities of lateral
grippers.
[0005] In order to permit the abovementioned positioning, adjusting members are associated
with each gripper and make it possible to move the gripper closer to or away from
the last. Subsequently, each of said pluralities of lateral grippers is borne by a
respective support member which, relative to the bearing structure, is movable along
a curved trajectory which encompasses the shoe-making last, so as better to adjust
the positioning of the lateral grippers relative to the specific geometry of the last.
This makes it possible to adjust the position of the lateral grippers rapidly to the
varying geometries of shoe-making lasts which, as is obvious, vary in accordance with
the type of footwear to be produced.
[0006] It is, however, necessary to point out that, as regards the central gripper, if the
geometry of the width of the tip of the last is varied, for example by changing to
a shape of footwear having a square front end rather than a rounded one, it is necessary
to use a gripper of different width. Therefore, when the geometry of the shoe-making
last varies, while in the case of the lateral grippers it is sufficient to reposition
the respective support member, in the case of the central gripper it becomes necessary
to replace said gripper with one of appropriate width.
[0007] That having been said, the complexity of the abovementioned machines and the bulk
of all the elements that form them result in a situation where there is insufficient
space around the central gripper to be able to operate with a tool, such as a spanner,
the use of which becomes necessary in order to carry out operations of loosening and
tightening the securing members that lock the central gripper on its support. As a
result, before the central gripper can be replaced, it becomes necessary to remove
the lateral grippers so as to create the necessary space around the central gripper
to operate with the tool, it being impossible to proceed manually without tools.
[0008] The removal of the lateral grippers, or even their mere loosening, entails a subsequent
need to adjust the position of the lateral grippers relative to the last. As may easily
be deduced, this adjustment has to be performed by trained personnel and takes time,
so that it has an adverse impact on the productivity of the machine, partly because
it has to be repeated each time the footwear model to be assembled is changed.
[0009] From the above it is evident that, within the footwear sector, there is a greatly
felt need to be able to undertake the replacement of the central gripper simply and
quickly, without the need to use specialized personnel.
[0010] It is an object of the present invention to devise a machine for the preassembly
and assembly of an upper on a shoe-making last which possesses structural and functional
features such as to meet the above requirement and, at the same time, eliminates the
disadvantages to which reference has been made.
[0011] This object is achieved by a machine for the preassembly and assembly of an upper
on a shoe-making last in accordance with Claim 1, which makes it possible to create
rapidly a sufficient space around the central gripper to operate with a tool so as
to permit easy replacement thereof, depending on the type of footwear.
[0012] Further features and the advantages of the machine according to the present invention
will become apparent from the description given below of a preferred example of embodiment
thereof, given by way of indication and without implying limitation, with reference
to the attached figures, in which:
Figure 1 shows a diagrammatic perspective view of the working zone of a machine according
to the invention for the preassembly and assembly of an upper on a shoe-making last;
Figure 2 shows a simplified plan view of Figure 1;
Figure 3 shows a perspective view in partial section of a detail of the machine according
to Figure 1;
Figure 4 shows a lateral view in section of Figure 3;
and Figure 5 shows a lateral view of a detail of the machine according to Figure 1.
[0013] With reference to the attached figures, 1 globally designates a machine according
to the invention for the preassembly and assembly of an upper on shoe-making last
3, with the sole of which an insole has been associated.
[0014] The machine 1 comprises a bearing structure 9 to which is fixed a support 4 having
a triangular upper surface of limited extent on which the last 3 is intended to bear
in alignment with its front part, in other words with its sole.
[0015] The last 3 is supported from below by the triangular surface of the support 4, in
a manner such as to present the upper 2 facing upwards, and is positioned in a manner
such as to extend from a rear part to a front part along a longitudinal axis (L-L).
[0016] The triangular surface of the support 4 is inclined so that its perpendicular, marked
Z-Z, is subvertical and substantially coincides with the line of sight of an operator
who, standing in front of the machine 1, is observing the upper surface of said support
4.
[0017] The machine 1 comprises an upper pushing device 7, two opposed lateral pushing devices,
both marked 8, and a rear pushing device, not shown in the figures, which are intended
to engage respectively with the back, the sides and the heel of the last 3, so as
to keep said last in pressing contact against the triangular surface of the support
4 and substantially immobilized in the working position.
[0018] The machine 1 is equipped with tensioning grippers, marked 5, 10 and 11, able to
engage the edge of the upper 2 and to pull said upper 2, causing it to adhere to the
last 3. The abovementioned tensioning grippers are positioned around the support 4
in a manner such as to be substantially facing the contour of the front part of the
sole of the last 3, positioned on the support 4.
[0019] The grippers 5, 10 and 11 are of the type described and illustrated in the same applicant's
document EP 0 582 027-B1, the content of which is explicitly incorporated here by
way of reference. Each gripper comprises a body which is provided at the upper end
with two jaws 33 and is fixed at the lower end to a manipulating rod 12 by means of
two arms (not shown) which define a parallelogram linkage system making it possible
to cause the opening and closing movements of the jaws 33. Each gripper is selectively
controlled for opening and closing, and can be selectively displaced in the direction
Z-Z by means of appropriate actuating means, so as to obtain the desired tensioning
of the leather of the upper 2 on the last 3.
[0020] The tensioning grippers comprise a central gripper 5 positioned along the longitudinal
axis L-L in alignment with the front part of the shoe-making last 3 and a first plurality
and a second plurality of lateral grippers, respectively marked 10 and 11, opposite
one another relative to the longitudinal axis L-L. As stated above, the grippers 5,
10 and 11 are positioned in a manner such as to surround the contour of the front
part of the sole of the shoe-making last 3.
[0021] The lateral grippers 10 of the first plurality (that on the left in Figure 2) and
the lateral grippers 11 of the second plurality (that on the right in Figure 2) are
mounted on the support member, respectively marked 13 and 14 and movable relative
to the bearing structure along a curved trajectory T which encompasses the support
4 on which the shoe-making last 3 is positioned. This makes it possible to adjust
the positioning of the lateral grippers 10 and 11 of each plurality to the geometry
of the shoe-making last 3. In substance, by moving each support member 13 and 14,
it is possible to obtain a simultaneous displacement of all the lateral grippers,
10 and 11 respectively, associated therewith.
[0022] In the example, each support member 13, 14 takes the specific form of a substantially
flat and rectangular supporting base 15, from the central portion of which extends
a vertical wall 16. From the upper end of the vertical wall 16, a bracket 18 extends
substantially parallel to a portion of the underlying supporting base 15. The bracket
18, the vertical wall 16 and the supporting base portion covered by the bracket 18
define a C-shaped structure. The two support members 13, 14 are disposed in a manner
such as to present the respective C-shaped structures facing one another and extending
in the direction of the longitudinal axis L-L of the machine 1. In substance, the
C formed by each support member 13, 14 is facing the support 4 on which the last 3
is positioned.
[0023] The bracket 18 and the underlying portion of the supporting base 15 of each support
member 13, 14 are provided with appropriate respective pluralities of through-holes,
one above the other, through which extend the rods 12 on whose upper ends the tensioning
grippers 10 and 11 are fixed. Connected to the lower end of each rod 12 is a pneumatic
cylinder 19 whereby the vertical movement of said grippers is obtained, intended to
ensure the correct tensioning of the upper 2.
[0024] As is apparent from Figure 3, in which only the support member 13 (that on the left
in Figure 2) is shown, the support member 13 provides operational support for four
lateral grippers 10, and an equal number of lateral grippers 11 are supported by the
support member 14.
[0025] Each support unit 13, 14 bears, with its base 15, on a working level 6 of the bearing
structure 9 disposed perpendicularly to the abovementioned direction Z-Z. The working
level 6 is thus substantially parallel to the sole of the shoe-making last 3. Alternatively,
the working level 6 may be replaced by a plurality of cross-pieces.
[0026] According to an advantageous feature, at least one support member 13, 14, and both
in the example shown, is or are mounted on a respective trolley or slide 20, 21, which
is movable from and to a remote position in which the respective pluralities of lateral
grippers 10, 11 is at a distance from the central gripper 5.
[0027] When the two trolleys 20, 21 are in the remote position, a sufficient space is created
around the central gripper 5 to manipulate a tool, such as for example a manipulating
spanner for loosening the bolts which provide the tightening of the central gripper
5 on the rod 12.
[0028] The machine 1 comprises means for actuating the two trolleys 20, 21 from and to the
remote position, in other words from an advanced operating position, in which the
lateral grippers 10, 11 are positioned close to the last 3 to a remote position and
vice-versa. Preferably, the movement of the two trolleys 20, 21 takes place simultaneously.
In this respect, it must be specified that Figure 2 refers to a plan view of the zone
of the machine 1 in which the grippers 5, 10, 11, the support members 13, 14 and the
two trolleys 20, 21 are present. However, simply for purposes of illustration, the
right-hand half of Figure 2 refers to a situation in which the trolley 21 associated
with the support member 13 is in the remote position, while in the left-hand half
of the same Figure 2 the trolley 20 associated with the support member 14 is shown
in the advanced, operating position.
[0029] Each trolley 20, 21 performs the displacement from the advanced, operating position
(shown in the left-hand half of Fig. 2) to the remote position (shown in the right-hand
half of Fig. 2) with a movement having a displacement component transverse to the
longitudinal axis L-L. Preferably, this displacement consists of a translatory movement
of each of the two trolleys 20, 21 in a direction X-X perpendicular to the longitudinal
axis L-L. In substance, the two trolleys 20, 21, during the movement, move away from
or towards one another.
[0030] As will be more clearly apparent from the continuation of the description, the translatory
movement proves to be advantageous to implement from the standpoint of the structural
simplicity of the machine 1, though it is possible to impose a rotational or rotational/translatory
movement on the two trolleys 20, 21 or, more specifically, on the support members
13 and 14 of the lateral grippers 10, 11. In a further alternative embodiment, it
is possible to provide a movement of the support members 13, 14 of the lateral grippers
10, 11 in a vertical direction or in the abovementioned direction Z-Z.
[0031] In the example shown, each trolley takes the specific form of a plate supported by
and shape engaged with sliding guides 22, which extend in the abovementioned direction
X-X below the working level 6 and are supported by the bearing structure 9 of the
machine 1.
[0032] Each support member 13, 14 is connected to the respective trolley 20, 21 by means
of two bolts 23 having the threaded shank extending in the direction Z-Z. In order
to permit movement of the support member 13, 14 relative to the trolley 20, 21 along
the curved trajectory T encompassing the support 4 and the last 3, slots 24 are provided
in the base 15 of each support member 13, 14, extending along the abovementioned trajectory
T, through which slots the shank of a respective bolt 23 extends. Alternatively, the
slots 24 may be replaced by a slit of greater length.
[0033] By analogy with what has been described above, slots 25 are made in alignment with
the bolts 23 in the working level 6, through which slots the shanks of the bolts 23
extend. The slots 25 extend in the transverse direction X-X. Clearly, the length of
the slots and their positioning is such as to allow each trolley 20, 21 the possibility
of movement in the manner described above between the advanced, operating position
and the remote position, and vice-versa, without the shanks of the bolts 23 interfering
with the working level 6.
[0034] In the example, the means for actuating the trolleys 20, 21 comprise a threaded bar
26 extending in said transverse direction X-X and pivotably supported in rotation
by the bearing structure 9. This threaded bar 26 is kinematically associated with
an electric motor (not shown) for the rotational actuation thereof and is in screw/nut
engagement with a portion, or appendage 27, of each of said trolleys 20, 21. Consequently,
one rotation of the threaded bar 26 produces to a translatory movement of the trolleys
20, 21 along the sliding guides 22.
[0035] It is appropriate to point out that, in order to obtain simultaneous movement together
or apart of the two trolleys 20, 21, it is necessary for the threaded bar 26 to have
two threaded lengths with opposing threads (right-hand and left-hand), the first of
these threaded lengths being in screw/nut engagement with the threaded appendage 27
of the trolley 20 and the other threaded length being in screw/nut engagement with
the threaded appendage 27 of the trolley 21.
[0036] The kinematic connection between the shaft of the electric motor and the threaded
bar 26 is produced by means of a chain transmission comprising a chain 28 engaging
with two pinions 29, 30 respectively keyed on the threaded bar 26 and on the shaft
of the electric motor.
[0037] The actuation of the support members 13, 14 along the curved trajectory T is obtained
by virtue of respective actuating cylinders, for example of the pneumatic type, which
act directly on the base 15 of the support members 13, 14 by means of a manipulating
rod 31.
[0038] The machine 1 further comprises means for folding the edge of the upper 2 over onto
the sole of the shoe-making last 3, and means for pressing the folded-over edge of
the upper 2 from below against the insole, following application of adhesive along
the edge of the insole.
[0039] In the example shown, the abovementioned means for folding over the edge of the upper
2 comprise two plates 17, curved so as to encompass the profile of the tip of the
last 3 and movable towards said last 3, while the abovementioned means for pressing
comprise a plurality of rod-like elements 32 that are movable towards the last 3 in
a manner such as to engage it from below with a predetermined elastic force.
[0040] The machine 1 is equipped with means 34 for distributing the adhesive along the contour
of the sole of the insole associated with the last 3.
[0041] The machine 1 is additionally equipped with actuating means, regulating and monitoring
means, control means and others also necessary to ensure the correct functioning thereof
during its working cycle. Such means are known per se and are not described below
or shown in the figures.
[0042] As may be appreciated from the above description, the machine according to the invention
for the preassembly and assembly of an upper on a shoe-making last makes it possible
to meet the above requirement and, at the same time, to overcome the disadvantages
to which reference was made in the introductory part of the present description.
[0043] Specifically, when it is necessary to replace the central gripper of the machine,
it is sufficient to reverse the two trolleys from the latter into the remote position
in order to create the necessary space around the central gripper 5 to operate with
a manipulating spanner on the bolts that ensure the tightening of the said gripper.
It should be pointed out that the reversing movement and the subsequent placement
of the abovementioned trolleys in the operating position, and hence also that of the
respective lateral grippers associated therewith, does not in any way entail the loss
of the position of said lateral grippers, any subsequent adjustment being unnecessary.
[0044] Yet a further advantage of the machine according to the invention lies in the structural
simplicity of the structural solution adopted.
[0045] Clearly, a person skilled in the art, in order to meet contingent and specific requirements,
will be able to introduce numerous modifications and variations into the machine described
above for the preassembly and assembly of an upper on a shoe-making last, all of these,
however, being contained within the scope of protection of the invention as defined
by the claims that follow.
1. Machine (1) for preassembling and assembling an upper (2) on a shoe-making last, comprising
a bearing structure (9) with which are associated:
- support means (4) for positioning, along a longitudinal axis (L-L) a shoe-making
last (3) extended between a front part and a rear part and on which an upper (2) is
supported;
- means (7, 8) for 'engaging the shoe-making last (3) and locking it relative to said
support means (4);
- tensioning grippers (5, 10, 11) to engage the edge of the upper (2) and to pull
said upper (2), causing it to adhere to the shoe-making last (3), said tensioning
grippers (5, 10, 11) being positioned around said support means (4) in a manner such
as to be substantially facing the contour of the sole of the last (3), said tensioning
grippers comprising a central gripper (5) positioned in alignment with the front part
of the shoe-making last (3) and a first plurality and a second plurality of lateral
grippers (10, 11) opposite one another relative to said longitudinal axis (L-L),
- actuating means (19) for actuating the tensioning grippers,
- at least one support member (13, 14) for one of said pluralities of lateral grippers
(10, 11), said support member (13, 14) being movable relative to the bearing structure
(9) along a trajectory encompassing said support means (4), in order to adjust the
positioning of the lateral grippers to the geometry of the last (3);
- actuating means (31) for actuating the support members (13, 14),
- means (17) for folding over the edges of the upper (2);
characterized in that:
- at least one support member (13, 14) is mounted on a trolley (20, 21), which is
movable from and to a remote position in which the respective plurality of lateral
grippers (10, 11) is at a distance from the central gripper (5) such as to create
a sufficient space for a tool to be manipulated around said central gripper (5), and
in that it comprises means for actuating said trolley.
2. Machine (1) according to Claim 1, in which both the support members (13, 14) are mounted
on a trolley, which is movable from and to a remote position in which the respective
plurality of lateral grippers (10, 11) is at a distance from the central gripper (5).
3. Machine (1) according to Claim 1 or 2, in which the displacement of said trolley (20,
21) from and to the remote position takes place with a movement having a displacement
component (A) transverse to said longitudinal axis (L-L).
4. Machine (1) according to Claim 3, in which the displacement of said trolley (20, 21)
from and to the remote position comprises a translatory movement in a direction (X-X)
transverse to said longitudinal axis (L-L).
5. Machine (1) according to Claim 4, in which said trolley (20, 21) is slidingly supported
by sliding guides (22) borne by the bearing structure (9).
6. Machine (1) according to Claim 5, in which said means for actuating said trolley (20,
21) comprise a threaded bar (26) extending in said transverse direction (X-X) and
pivotably supported in rotation by said bearing structure (9), said threaded bar (26)
being kinematically associated with an electric motor for the rotational actuation
thereof and being in nut/screw engagement with a portion (27) of said trolley (20,
21), one rotation of the threaded bar (26) producing a translatory movement of the
trolley (20, 21) along the sliding guides (22).
7. Machine (1) according to Claim 1, in which said support member (13, 14) and said trolley
(20, 21) are connected by means of bolts (23) solidly fixed to the trolley (20, 21),
a slot (24) being provided in the support member in alignment with each bolt (23)
and able to permit a relative movement of the support member (13, 14) relative to
the bolt (23) along said curved trajectory (T).
8. Machine (1) according to Claim 7, in which between said support member (13, 14) and
said trolley (20, 21) is interposed a portion (6) of said bearing structure (9) in
which apertures (25) are made for the passage of said bolts, said apertures (25) being
sufficiently extended to permit the movement of the bolts (23) together with the trolley
(20, 21) during the movement of the latter from and to the remote position.
9. Machine (1) according to Claim 1, in which said means for the positioning of a shoe-making
last (3) comprise a support (4) capable of supplying a resting surface for the sole
of the shoe-making last (3), the shoe-making last (3) being supported from below in
a manner such as to present the upper (2) facing upwards.
10. Machine (1) according to Claim 1, in which said support member (13, 14) is movable
relative to the bearing structure (9) along a curved trajectory (T) encompassing said
support means (4).