Automatic footwear parts processing machine

The present invention relates to an automatic machine for footwear processing such as card and gluing operations on the bottom of footwear and/or on soles.

Footwear processing machines having two or more processing stations and a plurality of supports for the footwear parts to be processed are known. In these machines the supports move between the stations to allow the processing sequence.

One footwear part is thus supported by the same support for all the planned processing operations. As an alternative there are machines in which the processing stations move on the supports.

For example machines which perform carding and glue spreading by means of a pair of heads, one for carding and one for gluing, which translate to move alternately to the work position on a support bearing the footwear are known.

To reduce idle times it has also been proposed to use two supports so that while one head performs one operation on the footwear in the support the other head performs the other operation on the other support. After completion of the processing operations the heads exchange position on the supports.

This solution displays various drawbacks. For example since both carding and gluing take place in one zone of the machine it is impossible to perform good cleaning of the shoe bottom before spreading the glue. In addition it is very difficult for the operator to visually check the carding before start of the glue spreading operation.

Generally it has been found that the use of one support for multiple processing operations involves drawbacks. For example it is difficult for the same type of support to adapt with equal efficiency to different processing operations and for many operations the supports are of a fairly complex and costly type and it would be preferable to not use them in transportation functions or mere waiting.

In addition in the known machines there are idle times which slow production and in particular during footwear parts loading and unloading operations.

The general purpose of the present invention is to overcome the above mentioned drawbacks and others by making available an automatic machine of the type which performs multiple operations on footwear parts to allow greater production efficiency without inappropriately engaging the footwear supports. Another purpose of the present invention and in particular for card and gluing operation is to keep the different operational zones well separated, permit cleaning after carding which would not pollute the gluing zone, and if required allow easy checking of the footwear part between one operation and the other.

In view of these purposes it was sought to provide in accordance with the present invention a footwear parts processing machine comprising at least two processing stations in it and a footwear parts gripping and transfer device movable between a withdrawing position for a footwear part from one of said stations and an unloading position for the footwear part.

To clarify the explanation of the innovative principles of the present invention and its advantages compared with the prior art there is described below with the aid of the annexed drawings a possible embodiment thereof by way of non-limiting example applying said principles. In the drawings:

• FIG 1 shows a front elevation view in the direction of arrow A of FIG 3 of a machine in accordance with the present invention,
• FIG 2 shows a plan view of the machine of FIG 1,
• FIG 3 shows a side elevation view of the machine of FIG 1, and
• FIGS 4 and 5 show a front and a side view respectively of a detail of the machine of FIG 1.

With reference to the FIGS a machine in accordance with the present invention comprises a first processing station fitted with a processing head 11 and a support 13, a second processing station fitted with a processing head 12 and a support 14, and at least one gripping and transfer device or unit 15 for footwear parts.

As clarified below, the transfer device is movable between a position for taking the footwear part from one station and an unloading position.

In a first embodiment the machine indicated as a whole by reference number 10 in FIG 1 provides the functions of carding and glue spreading and comprises a carding head 11 with a card 17 and a glue spreading head 12 with a dispenser 18 operating on a footwear item arranged respectively in a support 13 and 14. Between the two supports moves a powered transfer device 15 which by means of a gripper 16 grasps the footwear item in the carding support 13 and transfers it into the gluing support 14. In FIG 1 a footwear item 55 is shown on the carriage 14 and the gripper 16 which grips a second footwear item 56 is at midpoint between the two carriages.

The heads 11 and 12 are made in accordance with the prior art to be able to move on command their tools 17, 18 along the bottom of the footwear part located in the respective support 13, 14.

For example the heads can be articulated to rotate along inclined powered axes 19, 20 and run transversely to the machine with powered carriages 21, 22. A powered lifting and lowering movement along the longitudinal axis of the tool is also provided. In this manner by appropriately controlling the movements of the heads it is possible to follow the surface of a shoe bottom on the support. The carding head can provide exhaust and blowing means for cleaning the footwear part after carding so as to forward it clean to gluing.

As may be seen in FIG 2 the operating heads are arranged in side-by-side zones of the machine separated by a partition 23. The supports 13 and 14 are powered to run along parallel guides 24, 25 to translate between the carding and gluing zones 26, 27, transfer zones 28, 29 and loading & unloading zones 30, 31.

The transfer grip is movable on guides 32 above and transversely to the guides 24, 25 to move between the two transfer zones.

As may be seen better in FIG 4 the transfer device 15 comprises a carriage 33 of a transverse cylinder without rod forming the guide 32. On the carriage 33 is fixed a vertical carriage 34 of a vertical cylinder 35 on the lower end of which is fixed the grip assembly 16. In this manner by applying pressure to one of the two ends of the vertical cylinder the grip rises or falls. On the carriage 34 are also mounted two shock absorbers 36, 37 of known function.

As may be seen in FIG 5 which is a cross section along plane of cut V-V of FIG 4 the grip assembly is supported at the lower end of the vertical piston 35 through a horizontal guide 38 to run horizontally and transversely to the footwear on the supports. The grip assembly supports a plate 39 with a slot 40 extending horizontally parallel to the guide 38 and having a length equal to the transverse movement of the grip as clarified below.

A compressed air cylinder 41 has its stem passing through the slot 40. On the stem is screwed a head 42 with its narrower part inserted with little play in a hole in a bracket 43 integral with the vertical cylinder 35. In the space between the top of the head and the cylinder at both sides of the plate 39 are inserted two rings 44, 45 made of high-friction material. In the horizontal part of the plate 39 is fastened the gripping hand or grip 16 which when the cylinder 41 is not operated can be moved horizontally along the guide 38 for the entire length of the slot 40. The gripping hand is held elastically in a central position by means of two springs 54.

The need for the horizontal movement and the brake arises from the fact that the gripping hand always stops in the central position of the travel of each footwear support but the forms are not symmetrical. The hand must be able to make a small elastic lateral movement so that its jaws grip the footwear without moving it from its location.

The gripping hand is made up of a cylinder 47 equipped with rods 48 which move symmetrically and bear two flats 49.

Each flat 49 supports a plate 50 in the middle of which through the pin 51 is fastened a second plate 52 which supports two rubber fingers 53 which form the gripping jaw.

In this manner the plate 52 can rotate on the pin 51 so that both the fingers 53 rest against the side of a shoe which is grasped by the grip.

In use the machine initially has the support carriage 13 completely advanced in the loading position 30. The operator mounts the form with the footwear part on the support 13 and starts the machine. The carriage 13 backs to the working position 26 and the carding head performs carding in accordance with the program applied. Upon termination of the carding the carriage 13 advances to the transfer position 28 and the transfer device 15 grasps the footwear and transfers it from the support 13 to the support 14 waiting in the transfer position 29. During seizure of the footwear the brake 41 of the grip is released so that upon closing of the grip jaws 53 the entire grip can translate laterally to adapt to the asymmetrical position of the footwear. After tightening of the grip on the footwear the brake is locked to ensure holding of the position of the footwear in relation to the arm bearing the grip.

When it is empty the support carriage 13 advances again to move into the loading position and receive another footwear part while the carriage 14 backs to the working position 14 where the gluing head performs the applicable glue spreading program. In the meantime the carriage 13 transports the next mounted footwear part to the carding position 26 and another carding operation is started. The carding and gluing operations can therefore proceed parallel on the two footwear parts.

Once the gluing operation is terminated the carriage 14 advances to the unloading position 31 where the operator removes the footwear part from the machine and then backs to the transfer position 29 to receive another footwear part from the transfer device 15.

Since the transfer device 15 stops in an intermediate position of its travel as shown in FIG 1, if the receiving carriage is not free it may happen during the operating cycle that in the machine there be three footwear parts simultaneously and that is two in work and one waiting for the gluing operation.

It is now clear that the preset purposes have been achieved.

In an alternative embodiment the transfer device unloading position is not for loading of one of the processing stations but for emptying from the machine.

This was found particularly advantageous for machines equipped with heads 11, 12 both for gluing, one for glue spreading on the bottom of a footwear item and the other for spreading the glue on a sole. The supports 13, 14 should of course be suited to reception of the respective footwear part. For example the sole support could be a known plane surface with vacuum and/or mechanical locking.

Again with reference to FIG 2 in this alternative embodiment the transfer device is used to take the footwear from the respective support and carry it to the unloading position. In the embodiment of the example with two glue heads the footwear part indicated by reference number 55 may be the sole and the part indicated by 56 the shoe. The unloading position can again be at 28. The carriage 13 merely does not stop in this position to receive the footwear part from the transfer device but on the contrary to allow the transfer device to take from it the footwear part.

As an alternative the unloading position can be in another zone, for example at 28b, and to reach this unloading position the guide 32 can have an appropriate extension 32b. During operation of the machine the operator loads the two carriages with a sole and a shoe, then takes another sole & shoe pair to be glued from the conveyor, loads the shoe on the carriage which in the meantime was freed from the transfer device, takes the glued sole with the freed hand, deposits on the carriage the sole to be glued, takes the glued shoe from the transfer device and lastly deposits the glued sole and shoe on the conveyor.

Naturally the above description of embodiments applying the innovative principles of the present invention is given by way of non-limiting example of said principles within the scope of the exclusive right claimed here. For example transfer position and loading & unloading position for the two footwear part supports can coincide.

In addition as mentioned above the operations performed may be different from those shown or substations each performing part of the complete processing could be provided. In case of high production there can also be provided another transfer device 15b as indicated in broken lines in FIG 2 and virtually identical with the one shown at 15 and described above so as to allow transfer of the footwear parts without the need of waiting until the transfer device 15 or 15b is empty. This way it is possible for example for one transfer device to perform the transfer operation between processing stations while the other transfer device empties the downstream station while waiting for the operator to remove the processed footwear item from the machine. The transfer devices can be used both for transfer of footwear parts between the stations and for temporary parking of these parts between operations or at the end of processing. For example in the case of a gluing machine for two shoes a third shoe can remain in the transfer device so as to form a processing queue. In addition, as mentioned above, the operations performed can be different from those shown or substations each performing part of the complete processing can be provided.

The transfer of shoes or soles on the same machine could be done for the same or other operations.

Lastly, the data concerning the footwear in work such as size, type, left or right et cetera could be easily transferred from one station to the next so as to be shared by the various stations with no need for all the stations to have data collection devices.