[0001] The present invention concerns an automatic machine with a plurality of working stations,
to carry out machinings on the edge and bottom of footwear, particularly shoe cementing
operations.
[0002] Various types of automatic machines have since long been introduced on the market
to carry out different machinings on footwear, particularly roughening, seam reducing
and cementing operations, as well as applying heels and soles. All these machines
have evidently been proposed to reduce the number of specialized workers employed
in the footwear sector, both due to the increasing costs of this type of labour and
due to the progressive ever increasing shortage of the highly skilled labour required
to carry out some particularly delicate steps of this production.
[0003] A first type of automatic machines substantially reproduces the approach to handwork
and therefore consists of a machine with a single working station, equipped with one
or more tools to machine the shoe. On this type of machines, the operative positions
on the single working station only one shoe mounted on a last, and he starts the production
cycle which may consist of one or more successive operations, at the end of which
he removes the shoe which has been machined and introduces a new shoe; systems can
be provided to shift the support for the shoe, so as to facilitate its positioning
on and removal from the machine. An example of this type of automatic machine is described
in EP-A-0 388 674. This type of automatic machines is apt to perform a good machining
on the shoe, it has fairly reduced dimensions, but its productiveness is insufficiently
high due to the fact that the machine is fully inoperative while the shoes are being
positioned thereon and removed therefrom. The dead time reckoned for these operations
is in fact between 50% and 80% of the time required for the actual working step, according
to whether the machine performs a single or more successive operations on the shoe.
[0004] To overcome this drawback, a second more advanced type of automatic machines has
been introduced on the market, characterized in that it comprises a shoe loading station,
one or more working stations and, finally, an unloading station of the finished shoe.
Different solutions have been proposed for what concerns the number and distribution
of the working and loading/unloading stations, as well as the system to convey the
shoes from one station to the next. A first solution provides for an in-line machine,
wherein the first station is the loading station, followed by the required number
of intermediate working stations and ending with the unloading station. A second solution
provides instead for a rotary machine with four stations, wherein the first station
is used for the loading and unloading operations, while the other three stations are
used for the required machining operations. An example of this solution is described
in DE-41 04 468 (Leibrock); the improvement in respect of the previous solution lies
both in the fact of having eliminated the need for a double station to carry out the
loading and unloading operations, and in the fact of having given a more compact shape
to the machine, with evident advantages from the mechanical and plant layout point
of view. Both these solutions are however characterized by the large overall dimensions
of the machine which have highly conditioned the application thereof.
[0005] A third solution consists of a machine with only two stations, which provides for
means to alternately move between said stations two shoes mounted on lasts, the two
stations alternately acting one as a loading/unloading station and the other as a
working station, and viceversa. Thanks to this particular double function of the two
stations, it has been possible to realize this machine - described in EP-596.570,
in the name of the same Applicant - with an extremely compact design, whereby it has
met with great success on the market, particularly in its carding/cementing combination.
In fact, the replacement of a machine of the first aforementioned type with a machine
of this last type has allowed to increase its productiveness by 50%, without taking
up any additional space.
[0006] Encouraged by the success of this machine, the Applicant has become perfectly aware
that on the market, particularly that involving the small and medium shoe factories,
there is still a high requirement for automatic machines apt to perform machinings
on footwear, which - following the same basic concept of the machine described in
EP-596.570 - allow however to increase the productiveness, while substantially taking
up the same space as the already existing machines. Machines of this type allow in
fact to increase the cost-effectiveness of a shoe factory, without requiring any extension
of the production areas and even without requiring any changes in the distribution
of the machinery and of the respective utility plants, thereby easily overcoming the
resistances of this line of industrial activity against the innovation of the machinery,
which resistances are in fact mainly tied to the costs and times required for a complete
restructuring of the production units.
[0007] The object of the present invention is to thus supply an automatic machine to carry
out machinings on footwear which, while substantially taking up the same space as
the most compact automatic machines of known type, allows to significantly increase
the productiveness thereof.
[0008] According to the present invention, said object is reached by means of an automatic
machine to carry out machinings on the edge and bottom of footwear, of the type comprising
a plurality of working stations arranged according to a circular path, along which
move the shoes to be machined mounted on lasts, one of said stations being used for
the operations of loading the shoe to be machined and unloading the finished shoe,
characterized in that said circular path extends on a vertical plane. Other characteristics
of the automatic machine according to the present invention are described in the secondary
claims.
[0009] Further characteristics and advantages of the present invention will anyhow be more
evident from the following detailed description of some preferred embodiments of the
automatic machine to carry out machinings on footwear according to the invention,
given with reference to the accompanying drawings, in which:
Fig. 1 is a diagrammatic side elevation illustrating a first embodiment of the automatic
machine to carry out machinings on footwear according to the present invention, meant
for the operations of cementing the bottom and the edge of a shoe;
Fig. 2 is a diagrammatic front elevation of the automatic machine illustrated in fig.
1;
Fig. 3 shows, on an enlarged scale, a detail of fig. 1 which illustrates the first
working station used for both operations of loading the shoe to be machined and unloading
the finished shoe;
Fig. 4 shows, on an enlarged scale, a detail of fig. 1 which illustrates the second
working station used for the first machining on the shoe;
Fig. 5 shows, on an enlarged scale, a detail of fig. 1 which illustrates the third
working station used for the second machining on the shoe;
Fig. 6 is a diagrammatic front elevation of a second embodiment of the automatic machine
to carry out machinings on footwear according to the present invention, comprising
three working stations, meant for the operations of pounding and seam reducing at
the bottom of a shoe;
Fig. 7 is a diagrammatic front elevation of a third embodiment of the automatic machine
to carry out machinings on footwear according to the present invention, comprising
three working stations, meant for the operations of roughing and seam reducing at
the bottom of a shoe; and
Fig. 8 is a diagrammatic front elevation of a fourth embodiment of the automatic machine
to perform machinings on footwear according to the present invention, comprising four
working stations, meant for the operations of roughing, pounding and seam reducing
at the bottom of a shoe.
[0010] The general structure of the automatic machine to carry out machinings on footwear
according to the present invention is clearly illustrated in figs. 1 and 2. It comprises
a closed box-type frame T, onto a sidewall 1 of which is idly pivoted the shaft 2
of a rotating support 3 with a plurality of spokes 4. The shaft 2 is perpendicular
to the sidewall 1, while the spokes 4 extending therefrom lie on a plane parallel
to said wall and thus perpendicular to the shaft 2. The rotating support 3 is caused
to rotate by a main motor M
p through a conventional type belt transmission, both diagrammatically illustrated
in fig. 2. In the first embodiment of the invention - shown in figs. 1 to 5 - the
rotating support 3 comprises three spokes 4 positioned at 120° one from the other,
the number of spokes of the support 3 obviously determining the number of the working
stations in the machine.
[0011] The motor M
p is operated by an on-board processing unit - the control console C of which is positioned
in the front part of the machine - to cause the intermittent rotation of the support
3, so that the different spokes 4 of said support move their position in the respective
working stations, each of which is used to carry out a different operation or machining
on the shoe.
[0012] To allow carrying out these operations, each spoke 4 ends with suitable gripping
devices allowing to steadily block on the spoke, for the whole working cycle, a shoe
mounted on its last. The gripping devices are pneumatically operated through specific
compressed air channels extending along the shaft 2 and then branching off, by means
of a three-way rotating joint, in correspondence of channels each housed into the
three spokes 4, so that the feeding of compressed air to the gripping devices takes
place independently from the position of the support 3 and from its steady or moving
condition. The operation of the single gripping devices is thus obtained, in known
manner, by means of independent controls for each gripping device, so that each device
can be operated not only for the initial introduction and final removal of the shoe,
but also in the intermediate stations when required for the machinings carried out
on said shoes. Also the operation of the gripping devices is obviously controlled
by the internal processing unit according to the particular working cycle.
[0013] In the automatic machine according to the present invention, a new shoe to be machined
mounted on its last is introduced in station I, to which the operative can gain access
through an opening 5 provided in the front part of the machine. The blocking of the
shoe onto the end of the spoke 4 is illustrated in further detail in fig. 3, where
it can be seen that the last F, with its upper mounted thereon, is inserted on the
spoke 4 - through a pin/hole system known per se, and thus not illustrated - and set
in its position by a fixed heel support 6. The last F is then blocked in this position
by means of a pneumatically operated gripping device 7, which locks the neck of the
last F on both sides. Other systems to block the last can anyhow be adopted, without
thereby departing from the scope of the present invention.
[0014] Once the last F has thus been blocked in position onto the end of the spoke 4, the
on-board processing unit operates the motor M
p which causes the shifting by 120° of the rotating support 3, so that the shoe which
has just been positioned in station I is shifted onto the working station II, while
a new spoke 4 reaches the station I and is ready for a new shoe to be introduced thereon.
[0015] The working station II is illustrated in further detail in fig. 4. This station is
used to carry out the cementing of the lateral edge L of the shoe. The tool to spread
the adhesive substance consists of a cementing head 8, carrying at its front end the
brush 9 to spread the adhesive substance. The motion of the cementing head 8 is controlled
by the processing unit, according to a preset working program, by operating five motors,
X, Y, Z, A and B, which cause shifting of the cementing head 8 along the three orthogonal
axes X, Y and Z, and the rotation of said head about two mutually perpendicular axes
A and B, passing through the point of contact of the brush 9 with the edge of the
shoe.
[0016] In particular: the motor X controls the movement of the slide 10 along the guides
11; the motor Y controls the movement of the slide 12 along the guides 13 integral
with the slide 10; the motor A controls the rotation of the rotating support 14 about
the axis A integral with the slide 12; the motor Z controls the lifting/lowering of
the support 15 for the head 8 in respect of the rotating support 14; and, finally,
the motor B controls the rotation of the cementing head 8 in respect of the rotation
axis B. The axis B and the axis Y are perpendicular to the plane of the drawing shown
in fig. 4.
[0017] A subsequent rotation of the support 3, at the end of the machining carried out on
the shoe in station II, shifts said shoe onto station III, where the second machining
is carried out thereon. Said station is illustrated in detail in fig. 5. Station III
is used to carry out the cementing of the shoe bottom. The tool to spread the adhesive
substance consists of a cementing head 18, carrying at its front end the brush 19
to spread the adhesive substance. Also in this case, the motion of the cementing head
18 is controlled by the processing unit, according to a preset working program, by
operating five motors, X1, Y1, Z1, A1 and B1 - similar to those previously described
for station II - with a slightly different mechanical arrangement, as described hereunder.
[0018] In particular: the motor X1 controls the movement of the slide 20 along the guides
21; the motor Y1 controls the movement of the slide 22 along the guides 23 integral
with the slide 20; the motor Z1 controls the lifting/lowering of said slide 22 in
respect of the slide 20; the motor A1 controls the rotation of the rotating support
24 about the axis A1 integral with the slide 22; and, finally, the motor B1 controls
the rotation of the cementing head 18 in respect of the rotation axis B1. The axis
B1 and the axis Y1 are perpendicular to the plane of the drawing shown in fig. 5.
[0019] Fig. 6 illustrates a second embodiment of the invention, in which three working stations
are provided, similar to the previous ones, except that station II is used to carry
out a pounding operation, while station III is used to carry out a seam reducing operation.
[0020] Fig. 7 illustrates a third embodiment of the invention, with three working stations,
in which station II is used to carry out a roughing operation on the shoe upper, while
station III is used to carry out a seam reducing operation quite similar to that illustrated
in the second embodiment of the invention.
[0021] A last embodiment of the invention is finally shown in fig. 8 wherein, in a higher
machine, the rotating support 3 comprises four spokes 4 which thus determine four
corresponding working stations.
[0022] In addition to the first station I used to load/unload the shoe mounted on its last,
there are a second working station II for the roughing operation of the shoe upper,
a third working station III for the pounding operation on the heel of the shoe, and
a fourth and last station IV for the seam reducing operation.
[0023] The machine structure illustrated heretofore allows to perfectly reach the object
of the present invention. In fact, the plan overall dimensions of the aforedescribed
machine is substantially equal to that of a conventional machine with a single working
station. The space for the other two or three stations is in fact obtained by utilizing
the height of the machine which, normally, does not involve any problem of installation.
Moreover, the machine according to the first embodiment described heretofore has an
additional important advantage, in that cementing of the shoe edge is carried out
in station II, namely with the bottom of the shoe facing downwards. In this way, any
possible dripping of the adhesive substance cannot interfere with the shoe upper,
thereby notably reducing the amount of production rejects. When the shoe is then shifted
from station II to station III, the adhesive substance is already sufficiently dried
up as to no longer involve any dripping problem and then retain any dripping which
may be determined during cementing of the shoe bottom, without hence damaging the
integrity of the upper.
[0024] The invention has been described with reference to some preferred embodiments thereof,
but it is evident that its protection scope is not limited to such embodiments, but
includes any variant within reach of a person skilled in the art, provided that it
falls within the definitions given in the accompanying claims.
1. Automatic machine to carry out machinings on the edge and bottom of footwear, of the
type comprising a plurality of working stations arranged according to a circular path,
along which move the shoes to be machined mounted on lasts, one of said stations being
used for the operations of loading the shoe to be machined and unloading the finished
shoe, characterized in that said circular path extends on a vertical plane.
2. Automatic machine as in claim 1), wherein said shoes mounted on lasts (F) are blocked
onto the ends of the spokes (4) of a rotating support (3), having a number of spokes
(4) corresponding to that of said working stations, the rotation axis of said support
(3) coinciding with the axis of said circular path.
3. Automatic machine as in claim 2), wherein the means to block said shoes mounted on
lasts consist of pneumatically operated gripping devices (7).
4. Automatic machine as in claim 3), wherein said blocking means are fed with fluid under
pressure through channels integral with said spokes (4) and fed by a correspondent
number of channels housed into the shaft (2) of said support (3), through a multi-way
rotating joint.
5. Automatic machine as in any one of the previous claims, wherein three working stations
(I, II, III) are provided, two at a higher level and one at a lower level, the working
station at a higher level which is closer to the front part of the machine being the
first station (I) used to load and unload the shoe.
6. Automatic machine as in claim 5), wherein said working station at a lower level is
the second working station (II), used to carry out cementing of the lateral edge (L)
of the shoe, while the third working station (III) is used to carry out cementing
of the bottom of the shoe.
7. Automatic machine as in claim 5), wherein said working station at a lower level is
the second working station (II), used to carry out a pounding operation on the heel
of the shoe, while the third working station (III) is used to carry out a seam reducing
operation on the bottom of the shoe.
8. Automatic machine as in claim 5), wherein said working station at a lower level is
the second working station (II), used to carry out a roughing operation on the shoe
bottom, while the third working station (III) is used to carry out a seam reducing
operation on the bottom of the shoe.
9. Automatic machine as in any one of claims 1) to 4), wherein four working stations
(I, II, III, IV) are provided, two at a higher level and two at a lower level, the
working station at a higher level which is closer to the front part of the machine
being the first station (I) used to load and unload the shoe.
10. Automatic machine as in claim 9), wherein said working stations at a lower level are
the second (II) and the third (III) working station, respectively used to carry out
a roughing operation on the shoe and a pounding operation on the heel of the shoe,
while the fourth working station (IV) is used to carry out a seam reducing operation
on the bottom of the shoe.