APPARATUS FOR COLLECTING, DISTRIBUTING AND STORING FLEXIBLE LAMINAR ELEMENTS, IN PARTICULAR INDUSTRIAL HIDES
Technical field
The invention present relates to an apparatus for the collection, distribution and storage of flexible laminar elements, in particular of industrial hides, for inserting them in the various production phases of the tanning process.
Background art
Devices for the stacking of hides of the type above indicated are known, which are adapted to receive and stack the hides on benches or on trestles at the completion of production phases.
These machines operate substantially in the same manner as manual operators, who seize the hides after the various production stages and deposit them on benches or trestles.
Such devices however cannot be used for all products of the tanning manufacture.
They are still inaccurate in laying down the hides, cause thick folds or streakings, or slipping of the hides to the ground. All these inconveniences are unacceptable when the cost of the product is high, as in the case of valuable hides employed in the shoe or leather good sector.
A device of this type for stacking hides on special trestles is described in the
International patent application No WO98/43906, which includes a conveyor belt surface for conveying hides and slidably supported on a movable tray to
gradually adapt to the height of the pile of hides.
A drawback of this type of device is that it is not possible to insert the hides automatically in the operating machines of the different phases of the production.
It is in fact necessary, at every passage from one production phase to the following one, to spread the hides manually, for example on the conveyor belt in proximity of the inlet portion of a spraying machine or to the clutching zone of the rotative cylinders of polishing, printing or stretching machines.
Presentation of the invention
A general object of the present invention is to overcome the cited drawbacks by providing an apparatus for the collection, distribution and storage of flexible laminar elements, in particular of industrial hides, reliable and simple to operate.
A further aim of the invention is to carry out the collection, distribution and storage operations, with a high level of quality in handling the hides, reducing to the minimum the damage of the hides.
A particular aim is to reduce to the minimum operators' intervention during the operation of the apparatus by maximizing the quantity of functions carried out automatically.
In accordance with one preferred aspect of the invention, there is provided an apparatus for the collection, distribution and storage of flexible laminar elements, in particular of industrial hides during various phases of their production, which includes a first support unit and a second hide handling
unit, adapted to be operatively supported by the first unit, in which the first and second units are provided with releasable connecting means to allow their transfer both jointly and separately, and in which the second unit includes two rotating cylinders with substantially parallel axes, and there further being provided flexible conveying means for loading, unloading and stocking hides, in which the conveying means are provided with two extremity portions each respectively fixed to one of the cylinders.
Thanks to the modularity of the apparatus it is possible to collect, distribute and stock the hides in an optimal position, substantially eliminating operator intervention with reduced possibility of mistakes in the operations of insertion, distribution, collection or piling of the hides.
Advantageously, the apparatus includes a rod-shaped actuator element, disposed substantially parallel and in interposed position to the axes of the cylinder and handling in translation, which acts on the tape to dispose this latter in unfolded position by forming a substantially horizontal feature and plane for the loading/unloading of the hides from the apparatus itself.
It is thus possible to shape a section of the conveyor belt so as to make automatic insertion of hides easier in different operating machines used in the various production phases, holding them in an optimal and precise position with consequent qualitative increase of the finished product.
Brief description of the drawings
Further characteristics and advantages of the invention will become more apparent in light of the following detailed description of some preferred but not exclusive embodiments of an apparatus for the collection, distribution and storage of flexible laminar elements illustrated with the help of the attached
drawing sheets in which: figure 1 shows an overall view of a hide spraying machine on which the apparatus according to the invention is applied; figure 2 shows a perspective view of the first main element composing the apparatus according to the invention; figure 3 shows a perspective view of the second main element composing the apparatus according to the invention; figures from 4 to 7 show perspective views of the apparatus according to the invention in various sequences relative to the preparation operations; figures 8 and 9 show perspective views of details of the apparatus according to the invention; figures 10a, 10b, 1 1 a - 1 1 c show some details of the apparatus according to the invention; figure 1 2 shows a detail of the actuating and tensioning devices of the apparatus according to the invention; figures 13a -1 3c show side views of some sequences of the positioning of the tensioning and actuating devices of figure 1 2; figures 14, 1 5 and 1 6 show various operating positions of a component part the apparatus according to the invention.
Description of a preferred embodiment
With particular reference to the figure 1 , two hide distributing/collecting apparatuses 1 , 1 ', according to the invention, are placed in operating position in correspondence of a machine M, which carries out an operation of the production cycle of the hides P, for example spraying. One apparatus works as distributor of hides to be treated in the machine M while at the other extremity of the production line of the machine M, the second apparatus, identical to the first, operates as collector of treated hides.
The collecting / distributing apparatus 1 , illustrated in greater detail in figures 3 and 4, is made of two main parts including, the supporting unit 2 and the handling unit 3, both supported by wheels 4, 5, or by special trolleys allowing displacement in the work area manually or by automatic systems, of the type with magnetic guides.
The unit 2 is composed of a support frame 6 with connecting devices 7, 8, 9, 1 0 to operatively attach the handling unit 3 during the operations performed with the two units 2, 3 joined together. On one side of the frame 6 the connecting devices 7, 8 comprise driving means while those on the other side the connecting means 9, 10 have only a support function.
The connecting means of one side of the unit 2 are illustrated in detail in figure 8. They include an electric engine 1 1 , or similar driving means, and a reduction gear 1 2, for transmission of the rotation to a hollow hub 13 with tapered extremity 14.
This hub contains internally a quick docking system with radially displaceable spheres 1 5 which can be pushed in a radial direction by a pin 16 with tapered extremity moved by an hydraulic or pneumatic piston. The device achieves the quick docking with the axis 1 7, by displacement in the direction of its extremity, once the pin 1 3 is inserted in its seating. It is thus possible to transmit the rotation motion to the axis 1 7 of the cylinder 1 8, supported by the handling unit 3.
Both the connecting devices 7, 8 are supported by guides 1 9, so as to axially move under the action of hydraulic or pneumatic jacks 20, or equivalent means, that allow coupling and uncoupling of the axis 1 7.
The second coupling device 8 is similar to the first one and performs the
coupling with the axis of the second cylinder 21 of the handling unit 3.
The phases of the coupling operation of one of the coupling devices 7, 8 is illustrated in detail in figures 1 1 a, 1 1 b, 1 1 c.
The handling unit 3 supports two cylinders 1 8, 21 , each performing alternatively and reversibly a rolling up and unrolling function of a tape 22, depending on whether it operates as collector or distributor of the hides. The tape 22 is generally made of a continuous fabric that can reach a length of about 300 metres or more, but it can be made of series of tapes or wires placed side by side.
The support unit 2 includes also two guides 24, 25 provided with racks on which a carriage 25, provided with wheels 26, 27, 28 rolls. The carriage 25 can move on the guides 23, 24 by means of an electric motor 29. The carriage 25 includes also an actuating element 30 having the shape of a rod positioned horizontally and a stretching element 31 in the shape of a pendulum. The figure 1 2 illustrates in detail the stretching and actuating element.
As illustrated in figure 6, during the operations in which the support unit 2 and handling unit 3 operate jointly, a frame or trestle 32 is attached to them after the coupling of the two units 2, 3, thus extending the length of the guides 23, 24 so as to create a plate surface S, during unrolling of the tape sufficient to maintain the hides P stretched, which have to be collected or distributed by the same apparatus. This is illustrated in the figure 7. This trestle 32, or similar element, can also be a part of the operating machine M itself and be anchored to the apparatus 1 only at the moment of the coupling with the machine M.
Figures 1 3a, 13b, 1 3c show in detail the various phases of the extension of the actuating element 30, which is displaced on the racks by the carriage 25 moved by the motor 29 through a reduction gear.
The actuator departs from its backward rest position and arrives at the extended position, for the subsequent distribution of the collected hides in the upper cylinder after activation of the apparatus 1 .
Figure 1 3a shows the handling unit 3, with the loaded upper cylinder 1 8, already inserted in the support unit 3, with the actuating element 30 still retracted. The stretching element 31 is retracted in an upper horizontal position and is maintained in this position by an appropriate automatic control system.
In figure 1 3b the actuating element 30, in an intermediate position, is driven parallely to itself by the movement of the carriage 25 which is guided on the guides 23, 32. The pendulum stretching element 31 is still maintained in a raised horizontal position.
In figure 1 3c the actuating element has reached the foremost final position for distribution of the hides P. The stretching element 31 is released by the lifting device and moves downwards, in the working position, with an inclination optimally set so as to perform both the desired stretching action on the tape 22 and the compensating action during the rolling up of the tape on the lower cylinder 21 .
The sliding of the tape 22 on the apparatus 1 can occur at variable speed, dependent on the thickness of the hides and on the density at which they are loaded in the superior cylinder. Moreover the feeding speed of the hides in the various machine on which the apparatus 1 can operate can be different.
Control is necessary as, for example, in the distribution function of the hides, the advancement speed of the tape must be maintained strictly steady and equal to the speed of the operating machine which is served.
So, in order to guarantee a regular sliding of the tape 22, in accordance with the invention, the apparatus 1 is provided with an adequate control, not shown in the figures, performing a servo-diameter function: the upper cylinder 1 8 reduces its diameter, during its gradual unrolling and consequently it must increase its rotation speed to guarantee that the advancing speed remains constant, while the lower cylinder increases its diameter, by rolling up the tape released by the upper cylinder, and must thus reduce its rotation speed. The servo-diameter system is provided with two distinct closed loop controls: a speed control for the upper cylinder 18 and a position control for the lower cylinder 21 .
The closed loop speed control of the upper cylinder 1 8, that constitutes through a tension inverter and a three-phase asynchronous motor the drive of the upper cylinder, takes the speed as reference, that is the desired speed that the tape must have, from a first tachymetric device of the phonic wheel, encoder, tachymetric dynamo or similar type, placed on the operating machine to be served. This signal is compared to an analogous feed-back signal coming from a second tachymetric device placed on a roll 35, supported by the trestle 32 and driven in rotation by the tape 22 and detects the actual linear speed. The difference between the two signals, opportunely modified by a correcting network to guarantee the stability of the system, produces an error signal, which acts on the tension inverter and corrects the rotation speed of the asynchronous motor and consequently of the cylinder, in such a way to make it exactly equal to the reference speed, thus eliminating the error.
The second control system acts on the lower cylinder 21 and has the function of recovering or releasing the tape, guaranteeing a steady and ideal tension. The closed loop position control, which controls the operation of the lower cylinder 21 through a tension inverter and a three-phase asynchronous motor, detects the position reference through an opportune potentiometer, placed on the electric console, producing an exact tension signal. This tension signal corresponds to a given angular position of the stretching element 31 . An increase of the reference signal increases the wanted inclination of the stretching element 31 and then the wanted strain of the tape. The feed-back angular signal of the stretching element 31 is obtained by a rotative potentiometric transducer, that produces a tension signal corresponding to the angular position actually taken by the stretching element. The difference between the reference signal of and the feed-back signal produces the error signal, that corrects the rotation speed of the asynchronous motor and consequently of the lower cylinder by acting on the tension inverter, after being appropriately modified by a correcting network to guarantee steady working of the system.
In this way, for example, the cylinder speed increases or decreases if the stretching element falls or raises, to quickly recover or release the conveyor tape excess and restore the wanted angular position of the corresponding stretching element corresponding to the right tension of the tape itself. In this manner the error is eliminated and the apparatus has a regular, flowing and ready functioning.
This solution, in accordance with the invention, has the advantage that it is not necessary to detect at every moment the diameters of the two cylinder 1 8, 21 , which is a complicated operation and giving inaccurate results for the upper cylinder, since the presence of the hides inside it makes its surface very irregular. These two controls allow the provision of a precise system,
with very satisfactory response times.
In addition^ the coupling means 9, 10 placed on the part of the support unit 2 opposite to that of the first coupling means 7, 8, are provided with an appropriate height regulating means, like hydraulic or mechanical lifting jacks 36, 37, which performs also the centring function of the carpet by raising or lowering theirs pistons, on whose extremity are the seatings of the cylinder hubs 18, 21 .
By actuating the lifting jacks 36, 37 it is possible to raise or lower the cylinder axis to insert or release the handling unit 3 from the support unit 2.
The apparatus 1 works as follows. It is placed in correspondence of the exit of a machine M performing one of the production phases of the hides P. The hides, going out from the conveyor belt or tape of the machine are laid down smoothly on the tape 22 of the apparatus, in the zone S, which will bring the hides to roll up in spiral around the upper cylinder 1 8 together with the tape 22, moving with the same speed of the conveyor belt of the machine M.
At the end of this operation, a cylinder 1 8 loaded with hides is obtained which are wrapped in sequential and tidy way, protected from dust or from other possible contaminations, with the possibility of being stocked in a store or of being sent to following working steps on another machine.
For this reason, it is sufficient to remove the handling unit 3 from the support unit 2 and transfer it to another support unit positioned before the working plane of another machine used for a subsequent production process step. Here the upper cylinder 1 8 on which the hides P are wrapped inverts its rotation direction and it is unrolled so as to free the hides from its coils for their insertion in the new operating machine.
During these operations the control system regulates the tape speed which is equal to the feeding speed of the hides in the operating machine.
The fixed unit 2 allows also a quick rolling up of the whole tape 22 of the cylinder on which the hides wrapped so as, in case a hide stock doesn't complete the cylinder full loading capacity, to easily and rapidly remove the cylinder and stock it in a store, as illustrated in figure 1 6. The store, in fact, can be developed in height and be provided with special codified seatings to receive the cylinder 1 8 loaded with hides. With this hide storage system, in form of cylinders, a computer-based management and handling of the store is easier to accomplish as well as the mechanical handling of the cylinders.
The figure 14 and 1 5 represent two handling units in two different operative situations. The figure 14 shows the case of the lower cylinder 21 having the tape completely wound up around itself, while the upper cylinder 1 8 has only a few windings of the tape 22 rolled up. This is the condition of the handling unit 3 unloaded and ready to receive the hides when coupled to the support unit 2.
The figure 1 5 shows the opposite situation to the one just described, with the handling unit 3 with the upper cylinder 18 with the tape 22 completely rolled up, and holding in its windings the hides P collected in a preceding working phase on another operating machine, for example at the exit of a drying tunnel. This second situation corresponds to the condition of a loaded handling unit 3, and ready to release the hides, for a following working phase, after coupling to the support unit 2.
The figure 1 6 shows schematically the possibility of placing in a vertical store the cylinders loaded with hides, for a stocking period. This system of temporary storage of the hides has the big advantage of occupying a reduced
space and moreover guarantees perfect conservation conditions of the product with regard to possible environment contaminations at a limited cost.
Although the invention has been described with reference to particular means, material, and embodiments, it is to be understood that the invention is not limited to the particulars disclosed and extends to all equivalents within the scope of the claims.
The instant application is based upon Italian patent application VI98A000166, filed on 1 1 September 1 998, the disclosure of which is hereby expressly incorporated by reference thereto, and the priority of which is hereby claimed.