CN114514108A

CN114514108A - Feeding device and method for feeding a continuous elongated element

Info

Publication number: CN114514108A
Application number: CN202080069596.4A
Authority: CN
Inventors: A·蒙泰罗索
Original assignee: Pirelli Tyre SpA
Current assignee: Pirelli Tyre SpA
Priority date: 2019-10-16
Filing date: 2020-10-08
Publication date: 2022-05-17
Anticipated expiration: 2040-10-08
Also published as: WO2021074940A1; CN114514108B; EP4045275A1

Abstract

Feeding device (999) and method for feeding a continuous elongated element (900), wherein the continuous elongated element is gripped by means of a thrust actuator (5) between a first roller (1) and a second roller (2) arranged side by side, the first and second rollers having respective axes of rotation (101, 102) substantially parallel to each other, wherein the first roller (1) and the second roller (2) are rotated by a motor (8) and a transmission (14), to advance the continuous elongated element, to feed it to the feeding point (A) at a feeding speed, wherein the respective rotational speeds of the first roller (1) and the second roller (2) are controlled by a motor (8) and a transmission (14), in order to limit or prevent variations in the respective rotation speed due to the action of the continuous elongated element (900) exerted on at least one of the first roller (1) and the second roller (2).

Description

Feeding device and method for feeding a continuous elongated element

Technical Field

The present invention relates to a feeding device and a method for feeding a continuous elongated element, in particular for producing tyres.

Background

In the context of a tire production process, it is common to process or manipulate a continuous elongated element (e.g., a ribbon-like element) that is typically either entirely an elastomeric compound or comprises an elastomeric compound in combination with other elements.

The term "feeding" or the like means the conveying of the continuous elongated element through a feeding point for the purpose of any type of treatment (for example mixing, extrusion, cutting, unwinding or winding, coupling with other elements, calendering, etc.).

By "continuous elongated element" is meant a structurally bonded element having a longitudinal dimension (defined length) that is substantially greater than the remaining dimensions (defined width and thickness) and having a cross-section perpendicular to the longitudinal dimension of any shape (e.g., rectangular, circular, oval, irregular, etc.).

For example, it is known to feed a continuous elongated element to a continuous processing machine for continuously processing a material. The feeding of the continuous elongated element to the machine may or may not be carried out in combination with the feeding of the other components.

For the purposes of the present description and/or of the following claims, the expression "continuous processing machine" denotes a machine to which the material to be processed (for example, the continuous elongated element and/or the composition of the compound) is fed continuously (except possibly due to maintenance or changes in the desired product recipe) in order to obtain the desired product, and from which the product is discharged by a substantially continuous flow.

Continuous processing machines include continuous mixers for producing a compound (e.g., a masterbatch, an intermediate, or a final compound), such as two-screw mixers (i.e., twin screws, typically co-rotating), annular extruders (i.e., mixers having a plurality of co-rotating screws arranged in an annular arrangement), planetary extruders (i.e., mixers having a rotating central mandrel and a plurality of planetary mandrels arranged about and meshed with the central mandrel to rotate about the central mandrel and to rotate upon themselves with the rotation of the central mandrel). These mixers are capable of high-energy mixing of the materials introduced with them, both in the state of the individual components (separated or combined) and in the state of compounding (even cold), the active elements of the mixer (for example screws and/or mandrels) being characterized by the inclusion, along their longitudinal extension, of a conveying section (for example helical threads) for advancing the materials, interspersed with mixing sections (for example compression masticating elements and shear masticating elements).

Continuous processing machines also include extruders for producing semi-finished products (e.g., tread bands, beads, etc.) used in tire production, such as single-screw and twin-screw extruders (typically counter-rotating), extruders for semi-finished products (e.g., profilers), feed extruders for fabric sizing calenders. These extruders, although inevitably producing a low degree of mixing, mainly perform the function of pushing the compound towards the outlet mouth. These extruders do not generally produce compounds starting from separate ingredients.

The continuous elongated element can be fed directly to the feeding section of the continuous processing machine, wherein this feeding section generally comprises a feed screw (at least one) which captures the continuous elongated element and drags it to the mixing and/or conveying chamber of the processing machine. Usually, the continuous elongated element is fed to the feed screw of the above-mentioned machine simply by gravity alone, for example by means of a hopper.

"generally perpendicular" with respect to geometric elements (e.g., lines, planes, surfaces, etc.) means that the elements (or elements parallel thereto and incident to each other) form an angle between 90 ° -15 ° and 90 ° +15 °, preferably between 90 ° -10 ° and 90 ° +10 °, inclusive.

By "substantially parallel" with respect to the above-mentioned geometric elements is meant that these elements (or elements parallel thereto and incident to each other) form an angle between 0 ° -15 ° and 0 ° +15 °, preferably between 0 ° -10 ° and 0 ° +10 °, inclusive.

The terms "optical", "light", and the like refer to electromagnetic radiation that does not necessarily fall strictly within the optical band (i.e., the 400-700nm band), but rather falls more broadly within a broader neighborhood of the optical band, such as from ultraviolet to infrared (e.g., the wavelength of the optical radiation may be between about 100nm and about 10 μm).

By "matrix camera" is meant a camera whose pixels of the sensor are arranged according to a rectangular matrix of two dimensions of comparable length (e.g. the two dimensions differ by less than an order of magnitude, such as a 16 x 9, 4 x 3 or 3 x 2 format). By extension, a "matrix image" is a digital image acquired by a matrix camera.

The "optical axis" of a lens refers to the line along which the lens is rotationally symmetric.

"linear laser source" means a laser source capable of emitting a linear laser beam, i.e. a laser beam lying in a "propagation plane" and having, as propagation direction, a "propagation axis" belonging to the propagation plane and passing through the laser source. The intersection of a linear laser beam with a physical surface (e.g., the surface of an elongated element) having reflective/diffusive properties produces a "laser line".

Document US4718770 discloses a screw extruder comprising a feeding section whose feeding rollers are adjacent to the screw and run counter to the rotation of the screw.

Document JP2008126541A discloses a method of feeding a strand-like elastomer into an extruder having a screw and a feed roller arranged parallel to the screw and counter-rotating with respect to the rotation of the screw.

Disclosure of Invention

Typically, the feed screw of a continuous processing machine is connected to or coincident with at least one processing screw of the machine. For example, in a planetary extruder, the feed screw may coincide with the beginning of the central mandrel without satellites, or in a single screw extruder, the feed screw may coincide with the beginning of the conveying and pushing screw itself. Thus, the rotational speed of the feed screw is typically determined by adjustments made to the rotational speed of the processing screw for processing reasons (e.g., adjusting the degree of mixing or adjusting the amount of extrusion).

The applicant has observed that typically during the feeding of the continuous elongated element to the feeding portion of the continuous processing machine, the flow rate of the elongated element actually fed depends on the rotation speed of the feed screw, since the elongated element is caught and dragged by the feed screw. For example, as the feed screw rotational speed increases, it typically results in an increase in the actual feed flow rate, as the feed screw tends to drag a greater amount of elongated element into the machine (and vice versa).

The applicant has therefore observed that when the rotation speed of the working screw (or screws) varies for processing reasons, undesirable variations in the feed flow rate may occur.

The possible presence of feed rollers adjacent to the feed screw, as described in US4718770 and JP2008126541A, increases this undesirable dragging, since the feed rollers cooperate with the feed screw of the extruder to accurately drag the elastomeric strip-like material into the mixing chamber of the extruder itself.

The applicant has therefore felt the need to be able to separate from each other the rotation of the processing screw (and therefore of the feed screw) and the flow rate of the continuous elongated element actually fed, in order to improve and/or diversify the production process of the compound and/or the realization of the semifinished product. For example, the applicant has realised that it is advantageous to be able to adjust the rotation speed of the feed screw while keeping the flow rate of the elongated element actually fed constant. In particular, given a certain feed flow rate of the elongated elements, in certain stages of the continuous process, for example a mixing process, it may be useful to increase the rotational speed of the feed screw in order to enhance the mixing, but not at the same time increase the feed flow rate (since in this case no increase in the degree of mixing will be obtained, since there will be more elongated element material to be mixed, the result being a balance of the two effects).

Moreover, the applicant has also noticed that, in the above-mentioned cases, any dosing performed on the continuous elongated element upstream of the continuous processing machine may be damaged and/or distorted by the dragging effect of the feed screw.

The applicant has therefore faced the problem of feeding the continuous elongated element to the continuous processing machine in a controlled, autonomous manner and independent of the type and/or parameters and/or process conditions (for example the time trend of the process section, the rotation speed of the components, such as the rotation speed of the conveying and mixing screws, the feeding of other components, etc.) in order to diversify and/or improve the continuous processing process and/or to be able to guarantee an effective control of the flow rate of the actual feed (and therefore also to contribute to the possible dosing of the elongated element).

According to the applicant, the above problem is solved by a feeding device of a continuous elongated element, wherein the continuous elongated element is gripped between a pair of rollers which are rotated by and only through the action of a motor and a transmission.

According to one aspect, the present invention relates to a device for feeding a continuous elongated element.

The device includes:

-a first roller and a second roller arranged side by side, the respective axes of rotation of which are substantially parallel to each other, wherein the first roller is movable relative to the second roller along a direction of displacement to vary the mutual distance between the axes of rotation;

-a push actuator pushing the first roller towards the second roller, the push actuator acting on the first roller with an adjustable push force;

-a motor and transmission mechanically connected to the first and second rollers for rotating the first and second rollers about respective axes of rotation at respective rotational speeds so as to limit or prevent variations in the respective rotational speeds of the first and second rollers due to non-motor-generated effects exerted on at least one of the first and second rollers.

The expression "not said motor-generated action" means an action generated by any component not related to the motor and/or to the feeding device, for example and typically an action exerted by the continuous elongated element on the rollers (which generate a mechanical torque) when pulled by the continuous processing machine (for example by the feed screw).

According to one aspect, the invention relates to an apparatus, preferably for producing tyres, comprising a feeding device according to the invention and a continuous processing machine comprising a feeding screw having a respective axis of rotation, wherein said feeding device is arranged in the vicinity of said feeding screw. Preferably, the continuous processing machine is one of: planetary extruders, twin-screw mixers, ring extruders, single-screw extruders, twin-screw extruders, feed extruders for fabric encapsulation calenders, extruders for semi-finished products.

According to one aspect, the invention relates to a method for feeding a continuous elongated element.

The method comprises the following steps:

-providing a first roller and a second roller arranged side by side, the respective axes of rotation of the first roller and the second roller being substantially parallel to each other, wherein the first roller is movable with respect to the second roller along a displacement direction to vary the mutual distance between the axes of rotation;

-arranging said continuous elongated element between said first and second rollers;

-pushing the first roller towards the second roller with an adjustable thrust to nip the continuous elongated element between the first and second rollers;

-rotating the first and second rollers so as to advance the continuous elongated element to feed it continuously to a feeding point at a feeding speed,

-controlling the respective rotation speeds of said first and second rollers so as to limit or prevent variations in the respective rotation speeds due to the action exerted by said continuous elongated element on at least one of said first and second rollers.

The expression "controlling … … the speed of rotation" means that the actual speed of rotation imparted to the rollers is substantially equal to the desired value (for example given by the motor according to the process of the specific implementation), and that it consists in limiting or preventing the variation in the speed of rotation of the rollers due to the action exerted by the continuous elongated element on at least one of the rollers (i.e. not generated by the motor).

According to one aspect, the present invention relates to a tyre production process comprising a method for feeding a continuous elongated element according to the present invention.

According to the applicant, the first and second rollers are arranged side by side and have respective axes of rotation parallel to each other, wherein the first roller is movable with respect to the second roller along a displacement direction to vary the mutual distance between the axes of rotation, establishing in a simple manner a positioning interface (and a subsequent feeding interface) of the elongated element. The variation of the reciprocal distance between the rollers allows to create a space for inserting the continuous elongated element and subsequently to bring the first roller into contact with the elongated element. In this way, different sizes (typically thicknesses) and/or configurations of the elongate element can be accommodated.

Pushing the first roller towards the second roller allows gripping the elongated element and maintaining such gripping (e.g. dynamically) also when the dimension of the elongated element (e.g. the thickness of the elongated element) varies, which may for example follow a cross-sectional variation and/or surface defects such as protrusions and/or material defects. In this way, the elongated element can be made to follow the rotation imparted to the two rollers by the motor and the transmission, reducing and/or avoiding the slippage of the rollers with respect to the elongated element.

Furthermore, since the pushing force is adjustable, the elongated element may be clamped in a variable manner as desired and/or depending on the material from which the elongated element is made (e.g., soft materials may require less pushing force than harder and/or stronger materials).

The control of the thrust exerted on the first roller towards the other roller and of the respective rotation speed (for example, the motor and the transmission being able to limit or prevent the variation of the respective rotation speed of the rollers due to the action produced by the non-motor exerted on at least one of the rollers) cooperate in order to prevent or limit the possibility of the elongated element being dragged by a component unrelated to the feeding device (for example, the feed screw of the continuous processing machine).

In fact, when the feed screw pulls the continuous elongated element at a speed greater than the feed speed at which the rollers rotate, it is possible to prevent the elongated element from slipping through both rollers themselves, due to the thrust that keeps the rollers clamped on the elongated element, and moreover, due to the motor and transmission means as described above, it is possible to brake or preferably prevent the dragging of the elongated element against the rollers and the consequent excessive slipping of the elongated element.

In this way, it is possible to feed the elongated element only after the motor and the transmission means have imparted a rotation to the roller, and therefore in a controlled, autonomous manner, and independently of the type and/or parameters and/or conditions of the process.

In one or more of the above aspects, the invention may have one or more of the following preferred features.

Preferably, a feeding device according to the invention is provided.

Preferably, pushing the first roller towards the second roller is performed by the push actuator.

Preferably, rotating the first and second rollers and controlling the respective rotational speeds are performed by the motor and transmission.

Typically, the direction of advancement of the continuous elongated element is substantially aligned with the longitudinal dimension of said continuous elongated element.

Preferably, the section of the continuous elongated element substantially perpendicular to the direction of advancement of the continuous elongated element has a parallelogram profile, more preferably rectangular and/or having short and long sides with a length ratio greater than or equal to 10 (i.e. the element is strip-shaped). Preferably, said first and second rollers contact said continuous elongated element at said long edges (i.e. the rotation axis of the rollers is substantially parallel to the long edges of the section of the elongated element).

Typically, the continuous elongated element is composed of a homogeneous material. Preferably, the continuous elongated element comprises an elastomeric compound, or it is entirely constituted by an elastomeric compound.

Preferably, the tyre production process comprises mixing (for example, together with other ingredients or separately) or extruding the elastomeric compound (for example, by means of the continuous processing machine) after said feeding.

Preferably, said displacement direction is perpendicular to both said axes of rotation. Preferably, said thrust is directed along said displacement direction. In this way, the first roller moves and maintains the thrust towards the second roller in a rational manner.

Preferably, the motor comprises a first and a second motor unit, different from each other and comprising a first and a second motor shaft, respectively. For example, each motor unit may be: compressed air motors, electric motors (dc, ac, universal, brushless), hydraulic motors, internal combustion engines, and the like.

Preferably, the transmission means is interposed between the motor and the first and second rollers to mechanically connect the motor and the first and second rollers. In this way, the driving force is distributed to the rollers.

In one embodiment, each roller is directly keyed to the motor shaft of the respective motor unit (in other words, the transmission is coincident with the motor shaft and each motor unit is directly, mechanically connected to the respective roller).

Preferably, the transmission comprises a first transmission portion mechanically connecting the first motor unit to the first roller and a second (and different) transmission portion mechanically connecting the second motor unit to the second roller. In this way, each roller is independently motorized. Preferably, the first transmission portion and the first motor unit are integral with the first roller. In this way, the movement of the first roller in the displacement direction is facilitated, since the first motor unit and the first transmission part can also be moved together with the first roller independently of the second roller and the respective second motor unit and second transmission part. In this way, the feed device is manufactured in a simple manner.

In an alternative embodiment, the motor comprises one and only one motor unit. In this case, preferably, the transmission is configured to allow the first roller to move along the displacement direction while keeping the first and second rollers mechanically connected to the only one motor unit. For example, the transmission may comprise a chain transmission suitably dimensioned in a dynamic manner to allow such movement of the first roller while maintaining mechanical cooperation with said only one motor unit.

Preferably, the transmission comprises at least one input shaft and at least one output shaft, wherein preferably the input shaft receives rotation from the motor and the output shaft rotates the first and second rollers.

Preferably, the first and second transmission parts comprise respective first and second input shafts and respective first and second output shafts.

Preferably, the first and second input shafts are mechanically, more preferably rigidly, connected to the first and second motor shafts, respectively, for rotation with the first and second motor shafts, more preferably integrally.

Preferably, said first and second output shafts are mechanically, more preferably rigidly, connected to said first and second rollers, respectively, for rotating said first and second rollers.

The expressions "input shaft" and "output shaft" refer to the direction of distribution of the driving force (i.e. from the motor to the rollers through the transmission).

Preferably, the transmission, more preferably each of the first and second transmission parts, comprises a mechanical coupling between the respective input shaft and the respective output shaft for transmitting rotation of the respective input shaft to the respective output shaft so as to limit or prevent rotation of the respective output shaft other than that transmitted by the respective input shaft. Preferably, the mechanical coupling comprises a gear coupling of the worm-gear type (for example, the input shaft equipped with a worm and the output shaft integral with or connected to a gear meshed to the worm) arranged in succession from the respective input shaft to the respective output shaft, more preferably the mechanical coupling is constituted by the above-mentioned gear coupling. In this way, the rotation of the worm follows the rotation of the gear, which in turn transmits the rotation to the roller. At the same time, the worm mechanically prevents rotation of the gear when the gear is subjected to mechanical torque other than from the worm. In this way, it is achieved in a structurally simple manner that a variation of the respective rotational speeds of the first roller and the second roller due to a non-motor-generated action exerted on at least one of the rollers is prevented.

Alternatively or additionally, when the motor shaft is subjected to a torque "external" to the motor (i.e. not provided by the motor), the motor itself (e.g. the first and/or second motor unit) can apply a braking action to apply rotation to the roller independent of the external torque.

In one embodiment, the transmission may comprise a single input shaft for a single motor shaft of only one motor unit and a respective output shaft for each of said first and second rollers. In this case, preferably, the transmission comprises a respective mechanical coupling between the single input shaft and each respective output shaft, the respective mechanical coupling comprising at least one, more preferably all, of the above-mentioned features of the mechanical coupling of each of the first and second transmission parts.

Preferably, the transmission, more preferably each of the first and second transmission parts, is free of clutch members. In this way, the motor always remains engaged with the roller, further reducing the risk that the rotation speed of the roller may vary due to the action exerted by the non-motor.

Preferably, each of said first and second transmission parts comprises, more preferably consists of, a respective gearbox. In one embodiment, the reduction ratio of each gearbox is greater than or equal to 1:50, more preferably greater than or equal to 1:40, and/or less than or equal to 1:20, more preferably less than or equal to 1: 30. In this way, a desired drag torque (for example, according to the material of which the elongated element is made, typically according to the viscosity of the material) can be obtained at the roller.

Preferably, each of the first and second transmission portions is mechanically connected to the respective roller at a first longitudinal end of the respective roller.

Typically, the rotation of the first and second rollers has opposite directions (i.e., the rollers rotate in opposite directions).

Preferably, said rotation of said first and second rollers is such that the linear velocities of the respective side surfaces of said first and second rollers are substantially (i.e. less than 10% of theoretical) equal to each other. Typically, the first and second rollers have mutually equal radii and respective rotational speeds. In this way, the feeding of the additional elongated element is facilitated, reducing the risk that the roller may drag incorrectly, for example, which may scratch the surface of the elongated element.

Preferably, the feeding means comprise angular position sensors for the first and second rollers, respectively, for measuring the angular position of the first and second rollers, respectively (for example encoders). This angular position can be measured directly on the roller or indirectly, i.e. on the elements having the respective angular position uniquely associated with the above-mentioned angular position of the roller (for example, said first and second motor shafts, said first and second input shafts, said first and second output shafts, etc.).

Preferably, the feeding device comprises a command and control unit connected to the motor (more preferably to both the first and second motor units) and to each angular position sensor. Preferably, the command and control unit is programmed for commanding the motor at least as a function of the measurements of each angular position sensor. In this way, the rotation of the first and second rollers may be substantially synchronized.

Preferably, for each of said first and second rollers, said feeding means comprises a respective set of bearings (e.g. ball bearings, magnetic bearings, etc.) arranged at a first longitudinal end of the respective roller and/or at a second longitudinal end of the respective roller opposite to said first longitudinal end. In this way, the roller is supported while the rotation of the roller is promoted.

Preferably, each of said first and second rollers comprises a respective lateral surface which develops in a cylindrically symmetric manner about a respective rotation axis. In use, the lateral surface of each roller is placed in contact with the continuous elongated element.

Preferably, said lateral surface has a cylindrical development. In this way the contact area with the elongated element is maximized.

In an alternative embodiment, the lateral surface has a toothed development, i.e. it has a plurality of radial reliefs, preferably with right angles, wherein the reliefs of the first roller are staggered with respect to the reliefs of the second roller. In this way, the elongated element is cut into a plurality of strips along the advancement direction, facilitating the capture by the feed screw.

Preferably, said lateral surfaces of said first and second rollers are configured for gripping said continuous elongated element. Preferably, said side surfaces of the first and second rollers have a surface treatment (for example, said side surfaces are knurled or embossed) for increasing the coefficient of friction (for example, the static coefficient of friction) with said continuous elongated element. In this way, the retention force of the two rollers on the elongated element increases due to the thrust.

In one embodiment, the length over which the first roller can move along the displacement direction is greater than or equal to 5mm, more preferably greater than or equal to 10mm, and/or less than or equal to 30mm, more preferably less than or equal to 25 mm.

In one embodiment, the minimum distance between the side surfaces of the first and second rollers is greater than or equal to 2mm, more preferably greater than or equal to 4mm, even more preferably greater than or equal to 5mm, by virtue of the movement of the first roller. In one embodiment, the maximum distance between the side surfaces of the first and second rollers is less than or equal to 40mm, more preferably less than or equal to 30mm, even more preferably less than or equal to 25mm, depending on the movement of the first roller. In this way, elongated elements having various dimensions (for example, thicknesses) can be fed.

Preferably, the feeding means comprise a base body, more preferably rigid, which extends in the longitudinal direction, in the transverse direction and in the height, respectively. Typically, the longitudinal direction, the transverse direction and the height are substantially perpendicular to each other.

Preferably, the first roller is movable relative to the substrate. In one embodiment, said second roller is also movable relative to the substrate to vary said mutual distance between said axes of rotation. In this way, the stroke of each roller can be kept limited.

Preferably, said base body comprises a first and a second seat respectively housing at least partially said first and second roller.

Preferably, said first and second seats have respective main development directions substantially parallel to the longitudinal development direction of said base body.

Preferably, the respective axes of rotation of the first and second rollers are substantially parallel to the longitudinal direction. In this way, the rollers occupy their respective seats rationally.

Preferably, the displacement direction is substantially parallel to the transverse direction. In this way the first roller is moved reasonably relative to the substrate.

Preferably, the base comprises a through hole having an inlet mouth and an outlet mouth arranged on opposite sides of the base along the height. Preferably, said through hole is interposed between said first and second seats, said first and second seats being in communication with said through hole, more preferably contiguous to said through hole. In this way, a passage is made through the substrate, suitably arranged so that the continuous elongated element is interposed between the first roller and the second roller.

Preferably, the through-hole extends substantially along the height. In this way, a substantially straight channel is created for the elongated element.

Preferably, the first and second rollers at least partially occlude (preferably narrow a section of the passage of) the through-hole. In this way, the first roller and the second roller are able to interact with the elongated element inside the through hole.

Preferably, the first seat comprises a first portion remote from the through hole and of opposite shape to the circumferential portion of the side surface of the first roller. Preferably, said first seat comprises a second portion contiguous to said first portion, said second portion being close to (more preferably contiguous to) said through hole and shaped so as to provide a guide for sliding of said first roller along said displacement direction. In this way, the first roller can slide along the first seat to vary the degree of interference with the through hole.

Preferably, the second seat is opposite in shape to a circumferential portion of the side surface of the second roller. This saves space to reduce overall interference (encumbrance).

Optionally, the base body may comprise a further through hole, more preferably having a respective inlet mouth and a respective outlet mouth arranged at opposite sides of the base body along said height. In this way, further elements (typically non-continuous elongated elements, such as granular elements) can be fed.

Preferably, the side surfaces of the first and second rollers are accessible only through the through-holes (e.g. through the inlet mouths). In other words, the substrate surrounds the first and second rollers except at the through-holes. In this way, the moving parts of the device are enclosed within the matrix, increasing its intrinsic safety.

Preferably, the base body comprises a set of base elements that can be assembled together to form the base body, wherein the base elements have a main planar development along the longitudinal direction and the transverse direction and they are stacked along the height. In this way, the entire device can be assembled in a simple manner by stacking the base elements.

Preferably, the set of base elements comprises at least three base elements, more preferably three and only three base elements.

In one embodiment, the length of the inlet mouth of the through hole along the longitudinal direction is greater than or equal to 20cm, more preferably greater than or equal to 60cm, such as greater than or equal to 90cm, and/or less than or equal to 150cm, more preferably less than or equal to 120cm, such as less than or equal to 100 cm. The above dimensions allow easy feeding of elongated elements having various dimensions, typically a transverse width of between slightly less than 20cm and about 120 cm.

Preferably, said base body comprises respective housing seats for said transmission means and for said set of bearings, respectively.

Preferably, one or more (more preferably at least two) base elements comprise respective recesses shaped for forming, together with the base elements assembled together to form the base body, the first and second seats and/or the housing seat. In this way, it is possible to achieve a seat substantially completely inside the base body and/or with a significant undercut, for example a housing seat, typically of a set of bearings, for example to improve the intrinsic safety of the feed device and/or to further limit its encumbrance.

Preferably, the base element comprises male-female couplings at mutually facing surfaces, said male-female couplings being shaped to centre the base elements with respect to each other along the longitudinal direction and the transverse direction. In this way, stacking of the base elements becomes easier.

Preferably, said base body, more preferably the base element of said outlet mouth containing said through hole, comprises a thermal conditioning circuit, more preferably a thermal conditioning circuit for cooling. In fact, the feeding device is typically arranged in the vicinity of continuous processing machines, which are usually operated at high temperatures, which may be harmful to the feeding device. In the case of this thermally regulated base element, it acts as a heat insulator for the remaining base element.

Preferably, the push actuator comprises a first actuator element operatively connected to a first longitudinal end of the first roller, and more preferably it further comprises a second actuator element operatively connected to a second longitudinal end of the first roller opposite the first longitudinal end. For example, each actuator element may be a hydraulic or pneumatic piston (preferably with double action) or a linear electric actuator. In this way, the movement of the first roller is easily controlled, and the pushing force can be uniformly applied to the first roller.

Preferably, said thrust is adjusted according to the viscosity of said continuous elongated element. In this way, it is possible to adapt the device to various elongated elements, facilitating their feeding and reducing the risk of damaging the elongated elements and/or not providing a thrust force sufficient to move the elongated elements.

Preferably, said command and control unit is connected to said thrust actuator to regulate said thrust according to a value representative of the viscosity of said continuous elongated element. The value representative of the viscosity can be measured and transmitted directly to the command and control unit or entered manually by the operator.

According to one aspect, the present invention relates to a feeding apparatus of a continuous elongated element, comprising an advancement system for advancing said continuous elongated element along a first path in an advancement direction, said advancement system comprising a feeding device according to the invention, provided at an outlet of the first path, for continuously feeding said continuous elongated element at a feeding speed to a feeding point corresponding to said outlet of said first path.

The terms "upstream", "downstream", "intermediate, starting, end position", "inlet", "outlet", and the like refer to the relative position or arrangement between elements and/or zones of the apparatus with reference to the direction of advance of the continuous elongated element.

Preferably, the feeding device comprises a measuring system for continuously measuring on said continuous elongated element a quantity suitable for evaluating the actual flow rate of said continuous elongated element continuously fed to said feeding point.

The "flow rate" of a continuous elongated element refers to the quantity of continuous elongated element (quantity in volume or mass, correlated by the density of the material) delivered through a position per unit time.

Preferably, the feeding device comprises a respective command and control unit connected to said advancement system and to said measurement system and programmed for commanding said advancement system continuously in order to adjust said feeding speed continuously as a function of said measured quantity and a reference value of the feeding flow rate of said continuous elongated element in said feeding point.

In this way, the feeding device can dose the continuous elongated element, i.e. it can feed the continuous elongated element continuously to a feeding point (for example, to a continuous processing machine) by controlling its actual flow rate.

In fact, in the case of "irregular" continuous elongated elements (i.e. having a cross section that varies along the longitudinal direction of the elongated element), it may not be sufficient, for some applications, to control the feed speed in order to control the actual flow rate. The above-described feeding device also allows dosing of elongated elements that are "irregular", thanks to the measurement of quantities suitable for evaluating the actual flow rate and to the control of the feeding speed according to the quantities and to the feeding device according to the invention.

The expression "continuously" in relation to an operation relating to a continuous elongated element means that the operation is repeated closely in time in order to spatially resolve the elongated element in a suitable manner, for example so that the operation is carried out on successive contiguous points that are on the order of centimeters or even less than one centimeter from each other in the longitudinal direction of the elongated element.

Preferably, the command and control unit of the feeding device is operatively connected to, more preferably comprises, said command and control unit of the feeding device.

Preferably, said quantity comprises, more preferably corresponds to a quantity sufficient to calculate, at least approximately, a value representative of the area range of a section of said continuous elongated element on a plane substantially perpendicular to said advancement direction.

Preferably, the measuring system comprises at least one optical detection device for continuously detecting the geometrical information in a detection point along the first path. In this way, a non-contact detection is performed so as not to interfere with the advancement of the elongated element.

In an alternative embodiment, the quantity may be a mass per unit length (i.e. the longitudinal passage of the continuous elongated element is dynamically weighed by the measuring system as it advances).

Preferably, the geometric information comprises a height distribution of at least a part of the profile of the cross-section with respect to a reference height. In this way, the area range of the cross section can be calculated taking into account the actual distribution of at least a part of the profile of the cross section. In this way, possible defects of the elongated element (for example surface defects such as lack and/or excess of material, variations in the shape of the section, etc.) can be included in the calculation of the area range, so as to improve the accuracy of calculating the area range of the section.

Preferably, the optical detection means comprise a matrix camera having an optical axis and a linear laser source capable of emitting a linear laser beam having a propagation axis (arranged at a certain angle, for example 40 °, with respect to the optical axis). In this way, the geometrical information can be acquired by means of laser triangulation, which allows scanning through a line of the surface of the elongated element, i.e. a substantially point-like (nominal) scan along the longitudinal dimension, to obtain a height distribution of at least a portion of the profile of the cross-section (and therefore of the aforementioned surface of the elongated element as it advances).

In one embodiment, the geometrical information comprises a height distribution of a (substantially entire) contour of the cross-section. Preferably, said measuring system comprises a further optical detection device arranged on the opposite side of the continuous elongated element with respect to said optical detection device. Preferably, the further optical detection means comprises the same features of the optical detection means described above. In this way, the accuracy of the detection of the geometric information by means of laser triangulation is improved, since possible surface defects can also be detected on the other surface of the elongated element (for example, up to substantially also the entire geometric profile of the cross section).

Preferably, said command and control unit of said feeding device is programmed for continuously calculating, from said geometrical information, a value representative of the area range of said section. In this way, as a range of areas of the cross section substantially punctiform along the advancing direction, a high dosing accuracy can be achieved, since the actual flow rate (as described below) can be evaluated in a substantially punctiform manner.

Preferably, said command and control unit of the feeding device is programmed for continuously calculating a theoretical value of the feeding speed as a function of the ratio between said reference value of the feeding flow rate and said value representative of the area range of the section. In this way, the actual flow rate at the feed point can be implicitly estimated and compared with a reference value for the feed flow rate.

Preferably, continuously adjusting the feed speed comprises setting the feed speed equal to the theoretical value. In this way, the actual flow rate fed to the feed point corresponds to the desired flow rate value.

Preferably, continuously commanding the advancement system so as to continuously adjust the feed speed comprises continuously (only) commanding the feed device, more preferably continuously commanding the motor (more preferably each of the first and second motor units, even more preferably in a mutually independent manner) for adjusting (e.g. accelerating, decelerating) the rotation of the first and second rollers.

Preferably, said command and control unit of the feeding device is programmed for calculating (more preferably as a function of said feeding speed) the time delay taken for said section to travel from said detection point to said feeding point. Preferably, said command and control unit of the feeding device is programmed for continuously commanding said advancement system so as to continuously adjust said feeding speed also according to said time delay (more preferably, when said section has reached said feeding point). In this way, the physical extension of the feeding device is taken into account when adjusting the feeding speed (since the area range of the cross-section is calculated at a detection point which usually does not correspond to the feeding point).

Drawings

The characteristics and advantages of the invention will be further clarified by the following detailed description of some embodiments, presented by way of non-limiting example of the invention, with reference to the attached drawings, in which:

figure 1 schematically shows a section of a feeding device according to the invention (taken along the plane BB of figure 2);

FIG. 2 schematically illustrates a top view of the feeding device of FIG. 1;

FIG. 3 schematically illustrates a perspective view of some components of the feeding device of FIG. 1;

figure 4 schematically shows an arrangement according to the invention;

fig. 5 schematically shows a feeding device according to the invention.

Detailed Description

In the figures, the numeral 999 indicates as a whole a feeding device of the continuous elongated element 900.

Illustratively, the continuous elongated element 900 is constituted by a strip-like element made of a homogeneous green elastomeric compound. Exemplarily (fig. 2), a section 200 of the continuous elongated element perpendicular to the direction of advancement 100 of the continuous elongated element (in fig. 2, with the direction into the plane of the paper) is substantially rectangular (ignoring possible surface defects, not shown), for example rectangular with a long side of about 20cm long and a short side of about 3cm high.

The feeding device 999 exemplarily comprises a first roller 1 and a second roller 2 arranged side by side and each having a rotation axis 101, 102 (identified by the symbol + in fig. 1) parallel to each other, wherein the first roller 1 is movable with respect to the second roller 2 along a displacement direction 103, exemplarily perpendicular to both rotation axes 101, 102, in order to change a mutual distance D between the rotation axes 101, 102.

Exemplarily, the first roller 1 and the second roller 2 each have a respective side surface 4 which extends in a cylindrically symmetrical manner about a respective axis of

rotation

101, 102. Illustratively, in use, the lateral surface 4 of each roller is arranged in contact with the continuous elongated element 900 at the long side thereof (fig. 2 and 3).

Illustratively, the lateral surfaces 4 have a cylindrical development and they are configured for gripping the continuous elongated element 900. For this purpose, the lateral surfaces 4 of the first roller 1 and of the second roller 2 are exemplarily provided with a surface treatment (schematically represented by means of hatching in fig. 2 and 3) for increasing the static friction coefficient with the continuous elongated element 900 (for example, the lateral surfaces are knurled or embossed).

Exemplarily, the feeding device 999 comprises a pushing actuator 5 pushing the first roller 1 towards the second roller 2, acting on the first roller 1 with an adjustable pushing force directed along the displacement direction 103.

Exemplarily, the first roller 1 may be moved along the displacement direction 103 for a total length of about 20 mm.

Illustratively, the minimum distance between the side surfaces 4 of the first roller 1 and the second roller 2 is about 5mm and the maximum distance is about 25mm, depending on the movement of the first roller 1.

The push actuator 5 comprises, by way of example, an actuator element 6 constituted by a double-acting pneumatic piston (only schematically illustrated), which is, by way of example, operatively connected to a first longitudinal end 7 of the first roller 1.

Exemplarily, the feeding device 999 comprises a motor 8 and a transmission 14 mechanically connected to the first roller 1 and the second roller 2 to rotate the first roller 1 and the second roller 2 around the respective rotation axes 101, 102 at respective rotation speeds, in order to limit or prevent a variation of the respective rotation speeds of the first roller 1 and the second roller 2 due to an action exerted on at least one of the first roller and the second roller by the non-motor 8.

Illustratively, a transmission 14 is interposed between the motor 8 and the first and

second rollers

1, 2 to mechanically connect the motor and the first and second rollers.

Exemplarily, the motor 8 comprises a first motor unit 10 and a second motor unit 11 (schematically shown in fig. 2 and 3) comprising a first motor shaft 12 and a second motor shaft 13, respectively.

Exemplarily, the transmission 14 comprises a first transmission part 15 mechanically connecting the first motor unit 10 to the first roller 1 and a second transmission part 16 mechanically connecting the second motor unit 11 to the second roller 2. Exemplarily, the first transmission portion 15 and the first motor unit 10 are integrated with the first roller 1.

Illustratively, the first and

second transmission portions

15, 16 include respective first and

second input shafts

17, 18 and respective first and

second output shafts

19, 20.

Exemplarily (fig. 3), a first input shaft 17 and a second input shaft 18 are rigidly, mechanically connected to the first motor shaft 12 and the second motor shaft 13, respectively, to rotate integrally therewith, and a first output shaft 19 and a second output shaft 20 are rigidly, mechanically connected to the first roller 1 and the second roller 2, respectively, to rotate these rollers.

Illustratively, each

transmission portion

15, 16 includes a mechanical coupling (not shown) between the

respective input shaft

17, 18 and the

respective output shaft

19, 20 for transmitting rotation of the

respective input shaft

17, 18 to the

respective output shaft

19, 20 so as to limit or prevent rotation of the

respective output shaft

19, 20 that is not transmitted by the

respective input shaft

17, 18. The mechanical coupling consists, for example, of a gear coupling of the worm-gear type arranged in succession from the

respective input shaft

17, 18 to the respective output shaft 19, 20 (for example, not shown, the input shaft being equipped with a worm, the output shaft being integral with a gear meshing with the aforementioned worm). In this way, the geometry of the mechanical coupling physically prevents the rotation of the respective output shaft, which is not transmitted by the respective input shaft (the rotation of the gear is prevented, since it cannot produce a corresponding rotation of the worm about the respective axis, but only allows the transmission of the motion in the opposite direction, i.e. from the worm to the gear).

Illustratively, each

transmission part

15, 16 is free of clutch members.

Each

transmission part

15, 16 is constituted, illustratively, by a respective gearbox with a reduction ratio equal to 1:40 (i.e. the torque applied by the respective motor shaft connected to the transmission part multiplied by 40 is the torque at the output of the gearbox and the rotational speed of the input shaft divided by 40 is the rotational speed at the output shaft of the gearbox.

Exemplarily (fig. 2 and 3), each

transmission portion

15, 16 is mechanically connected to the

respective roller

1, 2 at the first longitudinal end 7, 87 of the respective roller.

Illustratively, the feeding device 999 comprises, for each roller, a respective angular position sensor 50 (e.g. an encoder) for measuring the angular position of the first roller 1 and of the second roller 2, respectively. Exemplarily, this angular position is measured indirectly at a first output shaft 19 and a second output shaft 20, which are rigidly connected to the respective rollers, having respective angular positions uniquely correlated to the above-mentioned angular positions of the rollers.

Illustratively, the feeding device 999 comprises a command and control unit 60 connected to the first motor unit 10 and to the second motor unit 11 and to each angular position sensor 50.

Illustratively, for each roller, the feeding device 999 comprises a set of ball bearings 70 arranged at a first longitudinal end 7, 87 (not shown) of the respective roller and at a second longitudinal end of the respective roller opposite the first longitudinal end 7, 87.

Illustratively, the feeding device 999 comprises a rigid base 21 that extends along mutually perpendicular longitudinal 201, transverse 202 and height 203 directions, respectively.

Exemplarily, the first roller 1 is movable relative to the substrate 21.

Exemplarily, the base body 21 comprises a first seat 22 and a second seat 23 shaped to house at least partially the first roller 1 and the second roller 2, respectively, the first seat 22 and the second seat 23 exemplarily having respective main directions of development substantially parallel to a longitudinal direction 201 of development of the base body 21.

Exemplarily, the respective axes of

rotation

101, 102 of the first and

second rollers

1, 2 are parallel to the longitudinal direction 201, and the displacement direction 103 is parallel to the transverse direction 202.

Illustratively, the base 21 includes a through-hole 24 extending along a height 203 and having an inlet mouth 25 and an outlet mouth 26 disposed on opposite sides of the base 21 along the height 203. Illustratively, the through hole 24 is interposed between the first seat 22 and the second seat 23, which communicate with and are contiguous to the through hole 24.

Illustratively, the length L of the inlet mouth 25 along the longitudinal direction 201 is equal to about 30 cm.

Exemplarily, the first roller 1 and the second roller 2 partially occlude the through hole 24 when being accommodated in the first seat 22 and the second seat 23, respectively, thereby narrowing a passage of the through hole 24.

Exemplarily, the first seat 22 comprises a first portion 27 distant from the through hole 24 and having an opposite shape to the circumferential portion of the side surface 4 of the first roller 1, and a second portion 28 contiguous to the first portion 27 and the through hole 24, said second portion being shaped as a sliding guide making the first roller 1.

Exemplarily, the second seat 23 is of opposite shape to the circumferential portion of the side surface 4 of the second roller 2.

Illustratively, the base 21 comprises a further through hole 29 having a respective inlet mouth 30 (shown in fig. 2) and a respective outlet mouth (not shown) arranged on opposite sides of the base 21 along the height 203.

Exemplarily, the side surfaces 4 of the first and

second rollers

1, 2 are accessible only through the through holes 24 (e.g. through the inlet mouth 25).

Illustratively, the base 21 includes a set of three base elements 31 that can be assembled together to form the base 21. Illustratively, base element 31 has a major planar extent (e.g., plates) along longitudinal direction 201 and transverse direction 203, and is stacked along height 203.

Illustratively, the base body 21 includes

respective housing seats

32, 33 for the transmission 14 and for the set of ball bearings 70, respectively.

Exemplarily, two base elements 31 (for example, a first and a second base element 31 arranged one after the other along a height 203 in a direction coinciding with the advancement direction 100, fig. 1) comprise respective recesses shaped for forming, together with the base elements 31 assembled to form the base body 21, the first and

second seats

22, 23 and the

housing seats

32, 33. Illustratively, once the base element 31 is assembled, the housing seat 33 of the set of ball bearings 70 is located inside the base body 21, while the housing seat 32 of the transmission 14 is in communication with the outside (for example, it opens in correspondence with at least one of its upper surfaces).

Illustratively, as shown in fig. 1, base element 31 includes male-female couplings at mutually facing surfaces that are shaped to center base element 31 with respect to each other along longitudinal direction 201 and transverse direction 202.

Illustratively, the base element 31 of the outlet mouth 26 containing the through hole 24 comprises a cooling circuit (not shown).

In use, the feeding device 999 allows to carry out a method for feeding the continuous elongated element 900.

Exemplarily, the continuous elongated element 900 is arranged between the first roller 1 and the second roller 2, and the first roller 1 is pushed towards the second roller 2 with a pushing force by the pushing actuator 5 for pinching the continuous elongated element 900 between the first roller 1 and the second roller 2.

Illustratively, the pushing force is adjusted according to the viscosity of the continuous elongated element. For this purpose, the command and control unit 60 is illustratively connected to the thrust actuator 5 to adjust the thrust according to a value representative of the viscosity of the continuous elongated element.

Exemplarily, the motor 8 is activated to rotate the first roller 1 and the second roller 2 in order to advance the continuous elongated element 900 to feed it continuously to the feeding point a at a feeding speed.

Illustratively, the respective rotation speeds of the first roller 1 and of the second roller 2 are controlled (for example, by the motor 8 and by the transmission 14) so as to limit or prevent variations in the respective rotation speeds due to the action exerted by the continuous elongated element 900 on at least one of the rollers.

Illustratively, the rotation of the first and

second rollers

1, 2 has opposite directions (i.e., the rollers rotate in opposite directions) and the linear velocities of the side surfaces 4 of the first and

second rollers

1, 2 are made equal to each other. Exemplarily, the radii and the respective rotational speeds of the first and

second rollers

1, 2 are equal to each other.

The command and control unit 60 is illustratively programmed for commanding the first motor unit 10 and the second motor unit 11 as a function of the measurement of each angular position sensor 50.

With reference to fig. 4, numeral 90 globally denotes an installation comprising a feeding device 999 according to the present invention and a continuous processing machine 80 comprising a feed screw 81 (also shown in fig. 1) having a respective rotation axis 105, wherein the feeding device 999 is arranged in proximity to the feed screw 81. The continuous processing machine 80 is exemplarily a planetary extruder, and the feed screw 81 is exemplarily coincident with the start portion 82 of the satellite-free central mandrel.

With reference to fig. 5, numeral 99 globally designates a feeding apparatus for a continuous elongated element 900, comprising an advancement system 91 for advancing the continuous elongated element 900 along a first path 110 in an advancement direction 100, the advancement system 91 comprising a feeding device 999 according to the present invention, arranged at the outlet of the first path 110, for continuously feeding the continuous elongated element 900 at a feeding speed to a feeding point a corresponding to the outlet of the first path 110.

Illustratively, the feeding device 99 comprises a measuring system 92 for continuously measuring on the continuous elongated element a quantity suitable for evaluating the actual flow rate of the continuous elongated element continuously fed to the feeding point a.

Illustratively, the quantities suitable for evaluating the actual flow rate of the continuous elongated element correspond to geometrical information relating to the section 200 of the continuous elongated element 900. Illustratively, the geometrical information comprises a height profile of at least a portion (not shown) of the profile of the section 200 with respect to a reference height (for example, the side surface of the support roller 403 of the advancement system 91 on which the elongated element is rested).

Exemplarily, the measuring system 92 comprises a single optical detection device 94 (schematically shown) for continuously detecting, in a detection point R along the first path 110, a height distribution of a portion of the profile of the cross section facing the optical detection system 94 with respect to the side surface of the support roller 403. For this purpose, the optical detection device 94 is illustratively based on laser triangulation techniques and comprises a matrix camera (not shown) having an optical axis 300 and a linear laser source (not shown) adapted to emit a linear laser beam 301 having a propagation axis (illustratively, forming an angle of about 40 ° with the optical axis 300).

In one embodiment (not shown), the measuring system may comprise a further optical detection device comprising the same features as the optical detection device described above and arranged on the opposite side of the elongated element (i.e. below the elongated element) with respect to the single optical detection device 94 for detecting the height distribution of another portion of the profile of the cross-section at a further detection point offset with respect to the support roller 403 along the longitudinal extension of the elongated element (so that the support roller does not interfere with the detection).

The feeding device 99 comprises, illustratively, respective command and control units 93 connected to the advancing system 91 and to the measuring system 92, said command and control units illustratively comprising the command and control unit 60 of the feeding apparatus 999.

Illustratively, the command and control unit 93 of the feeding device 99 is programmed for continuously commanding the advancing system 91 for continuously adjusting the feeding speed according to the quantity measured by the measuring system 92 and a reference value of the feeding flow rate of the continuous elongated element 900 at the feeding point a.

For example, the command and control unit 93 of the feeding device 99 is illustratively programmed for continuously calculating a value representative of the area range of the section 200 from the height distribution, and for continuously calculating a theoretical value of the feeding speed from the ratio between a reference value of the feeding flow rate and the value representative of the area range of the section 200. Illustratively, continuously adjusting the feed speed comprises setting the feed speed equal to a theoretical value, and continuously commanding the advancement system 91 so as to continuously adjust the feed speed illustratively comprises continuously commanding each of the

motor units

10, 11 so as to adjust (e.g., accelerate, decelerate) the rotation of the first and

second rollers

1, 2.

Exemplarily, the command and control unit 93 of the feeding device 99 is programmed for calculating, from the feeding speed, the time delay it takes for the section 200 to travel from the detection point R to the feeding point a, and for continuously commanding the advancement system 91 to continuously adjust the feeding speed also according to the above-mentioned time delay (for example, when the section 200 has reached the feeding point a).

The first passage 110 illustratively comprises a detection portion 111 comprising a detection point R, wherein illustratively an entrance of the detection portion 111 coincides with an entrance of the first passage 110. Illustratively, the first passage 110 includes a buffer portion 112 disposed downstream of and contiguous with the detection portion 111, wherein, illustratively, an outlet of the buffer portion 112 coincides with an outlet of the first passage 110.

Illustratively, the advancement system 91 is adapted to subject the continuous elongated element to a tension along both the detection portion 111 and along the buffer portion 112, wherein, illustratively, the reference tension along the buffer portion 112 is less than the reference tension along the detection portion 111 (as indicated by the bend formed by the elongated element). The lower tension along the buffer portion 112 provides sufficient material to avoid the possibility of the elongated element being overstretched (which could damage the elongated element and/or break the elongated element) after the feed speed is adjusted by the advancing device 999.

Illustratively, the feeding device 99 comprises respective tension sensors 95, 96 for the detection portion 111 and the buffer portion 112, respectively, which are adapted to continuously (e.g. without contact) detect the tension of the continuous elongated element along a respective one of the detection portion 111 and the buffer portion 112.

Illustratively, the command and control unit 93 of the feeding device 99 is connected to each tension sensor 95, 96.

Illustratively, the advancement system 99 comprises

respective advancement devices

97, 98 for the detection portion 111 and the buffer portion 112, respectively, which are arranged at the entrances of the detection portion 111 and the buffer portion 112, respectively, and are configured for adjusting the advancement of the continuous elongated element. Illustratively, the advancing

devices

97 and 98 are configured for braking and advancing, respectively, the continuous elongated element.

Illustratively, each

advancement device

97, 98 is configured for gripping the continuous elongated element. Illustratively, each advancing

device

97, 98 comprises a main roller M controllable by the command and control unit 93 of the feeding apparatus 99 and a further roller F arranged parallel to the main roller M and kept pushed against the main roller M (optionally, this further roller can also be controlled by the command and control unit 93 of the feeding apparatus 99).

Exemplarily, the command and control unit 93 of the feeding device 99 is further programmed for successively comparing the tensions detected along the detecting portion 111 and the buffering portion 112, respectively, with respective reference tensions and for successively commanding the respective advancing

means

97, 98 according to the respective comparisons between the tensions detected along the detecting portion 111 and the buffering portion 112, respectively, and the respective reference tensions.

Illustratively, the feeding device 99 comprises, upstream of the first passage 110, a centring portion for centring the elongated element. At this centring portion, the feeding device 99 comprises, by way of example, a further advancing means 400 for unloading the elongated element by dragging it from a possible storage means (not shown), such as a tray, a reel or the like, a further tension sensor 401 for detecting the tension of the elongated element along the centring portion, and a pair of rollers having vertical axes 402 (only one of which is visible) for centring the elongated element (for example, by twisting) in cooperation with the further advancing means 400 and/or with the advancing means 97 located at the entrance of the detecting portion 111. Exemplarily, the command and control unit 93 of the feeding device 99 is connected to the further detection means 400 and to a further tension sensor 401.

Claims

1. A feeding device (999) of a continuous elongated element (900), comprising:

-a first roller (1) and a second roller (2) arranged side by side, the respective axes of rotation (101, 102) of which are substantially parallel to each other, wherein the first roller (1) is movable with respect to the second roller (2) along a displacement direction (103) so as to vary a mutual distance (D) between the axes of rotation (101, 102);

-a pushing actuator (5) that pushes the first roller (1) towards the second roller (2), acting on the first roller (1) with an adjustable pushing force;

-a motor (8) and a transmission (14), said motor and said transmission (14) being mechanically connected to said first (1) and second (2) rolls for rotating said first (1) and second (2) rolls around said respective rotation axes (101, 102) at respective rotation speeds, so as to limit or prevent variations in the respective rotation speeds of said first (1) and second (2) rolls due to effects exerted on at least one of said first (1) and second (2) rolls not produced by said motor (8).

2. The feeding device (999) according to claim 1, wherein the displacement direction (103) is perpendicular to both of the respective rotation axes (101, 102), and wherein the thrust is oriented along the displacement direction (103).

3. The feeding device (999) according to any one of the preceding claims, wherein the motor (8) comprises a first motor unit (10) and a second motor unit (11), the first and second motor units comprising a first motor shaft (12) and a second motor shaft (13), respectively, wherein the transmission (14) is interposed between the motor (8) and the first and second rollers (1, 2) to mechanically connect the motor and the first and second rollers, wherein the transmission (14) comprises a first transmission part (15) mechanically connecting the first motor unit (10) to the first roller (1) and a second transmission part (16) mechanically connecting the second motor unit (11) to the second roller (2), and wherein the first transmission portion (15) and the first motor unit (10) are integral with the first roller (1).

4. The feeding device (999) according to claim 3, wherein the first transmission part (15) and the second transmission part (16) comprise a respective first input shaft (17) and second input shaft (18) and a respective first output shaft (19) and second output shaft (20), wherein the first input shaft (17) and the second input shaft (18) are mechanically, preferably rigidly, connected to the first motor shaft (12) and the second motor shaft (13), respectively, for rotation with said first motor shaft (12) and said second motor shaft (13), preferably integrally, wherein the first output shaft (19) and the second output shaft (20) are mechanically, preferably rigidly, connected to the first roller (1) and the second roller (2), respectively, in order to rotate the first roller (1) and the second roller (2).

5. The feeding device (999) according to claim 4, wherein each of the first transmission portion (15) and the second transmission portion (16) comprises a mechanical coupling between the respective input shaft (17, 18) and the respective output shaft (19, 20) for transmitting the rotation of the respective input shaft (17, 18) to the respective output shaft (19, 20) in order to limit or prevent the rotation of the respective output shaft (19, 20) transmitted by a non-respective input shaft (17, 18), and wherein the mechanical coupling comprises a gear coupling of the worm gear type arranged one after the other from the respective input shaft (17, 18) to the respective output shaft (19, 20).

6. The feeding device (999) according to any of the claims 3 to 5, wherein the transmission device (14), preferably each of the first transmission part (15) and the second transmission part (16), is free of clutch members, and wherein each of the first transmission part (15) and the second transmission part (16) comprises a respective gear box.

7. The feeding device (999) according to any one of the preceding claims, wherein each of the first roller (1) and the second roller (2) comprises a respective side surface (4), the side surfaces (4) extending in a cylindrically symmetric manner about the respective axis of rotation (101, 102), wherein the side surfaces (4) have a cylindrical extension, wherein the side surfaces (4) are configured for gripping the continuous elongated element, and wherein the side surfaces (4) have a surface treatment for increasing a coefficient of friction with the continuous elongated element.

8. The feeding device (999) according to any one of the preceding claims, wherein the first roller (1) is movable along the displacement direction (103) by a length greater than or equal to 5mm, and/or less than or equal to 30mm, and wherein, depending on the movement of the first roller (1), a minimum distance between the side surfaces (4) of the first roller (1) and the second roller (2) is greater than or equal to 2mm, a maximum distance being less than or equal to 40 mm.

9. The feeding device (999) according to any one of the preceding claims, wherein the feeding device comprises a base body (21) stretched along a longitudinal direction (201), a transverse direction (202) and a height (203), respectively, wherein the first roller (1) is movable relative to the base body (21), wherein the base body (21) comprises a first seat (22) and a second seat (23) that accommodate at least partially the first roller (1) and the second roller (2), respectively, wherein the base body (21) comprises a through hole (24) having an inlet mouth (25) and an outlet mouth (26) arranged on opposite sides of the base body (21) along the height (203), wherein the through hole (24) is interposed between the first seat (22) and the second seat (23), the first seat (22) and the second seat (23) being in communication with the through hole (24) and preferably with the through hole (24) Wherein the first roller (1) and the second roller (2) at least partially obstruct the through-hole (24), and wherein the side surfaces (4) of the first roller (1) and the second roller (2) are only accessible through the through-hole (24).

10. The feeding device (999) according to claim 9, wherein the base body (21) comprises a set of base elements (31) which can be assembled together to form the base body (21), wherein the base elements (31) have a main plane development along the longitudinal direction (201) and the transverse direction (202) and are stacked along the height (203), wherein the set of base elements comprises at least three base elements, wherein one or more base elements (31) comprise a respective recess shaped for forming the first seat (22) and the second seat (23) together with the base elements (31) assembled together to form the base body (21), and wherein the length (L) of the inlet mouth (25) of the through hole (24) along the longitudinal direction (201) is greater than or equal to 20cm, And/or less than or equal to 150 cm.

11. A feeding apparatus (99) of a continuous elongated element (900), comprising an advancement system (91) for advancing the continuous elongated element along a first path (110) in an advancement direction (100), said advancement system (91) comprising a feeding device (999) according to any one of the preceding claims, which is provided at an outlet of the first path (110) for continuously feeding the continuous elongated element at a feeding speed to a feeding point (A) corresponding to the outlet of the first path (110), wherein the feeding apparatus (99) comprises a measuring system (92) for continuously measuring on the continuous elongated element a quantity suitable for evaluating an actual flow rate of the continuous elongated element continuously fed to the feeding point (A), wherein the feeding apparatus (99) comprises a command and control unit (93), said command and control unit is connected to said advancement system (91) and to said measurement system (92) and is programmed for continuously commanding said advancement system (91) so as to continuously adjust said feeding speed as a function of said measured quantity and of a reference value of the feeding flow rate of said continuous elongated element in said feeding point (a).

12. The feeding apparatus (99) according to claim 11, wherein said quantity comprises geometrical information sufficient for calculating, at least in an approximate way, values representative of the extent of the area of a section (200) of the continuous elongated element (900) on a plane substantially perpendicular to the advancing direction (100), and wherein the measuring system (92) comprises optical detection means (94) for detecting said geometrical information continuously in a detection point (R) along the first passage (110).

13. The feeding apparatus (99) according to claim 12, wherein the geometrical information comprises a height distribution of at least a portion of the profile of the cross-section (200) with respect to a reference height, and wherein the optical detection device (94) comprises a matrix camera having an optical axis (300) and a linear laser source capable of emitting a linear laser beam (301) having a propagation axis.

14. The feeding apparatus (99) according to any one of claims 11 to 13, wherein the command and control unit (93) is programmed for continuously calculating, from the geometrical information, a value representative of an area range of the section (200) and for continuously calculating, from a ratio between the reference value of the feeding flow rate and the value representative of the area range of the section (200), a theoretical value of the feeding speed, wherein continuously adjusting the feeding speed comprises setting the feeding speed equal to the theoretical value, wherein continuously commanding the advancement system (91) so as to continuously adjust the feeding speed comprises continuously commanding the feeding device (999), and wherein the command and control unit (93) is programmed for calculating a time delay taken for the section (200) to travel from the detection point (R) to the feeding point (a) and for continuously commanding the advancement system (91) to continuously command the feeding device (999) The feed speed is continuously adjusted according to the time delay.

15. An installation (90) comprising a feeding device (999) according to any one of claims 1 to 10 and a continuous processing machine (80), the continuous processing machine (80) comprising a feed screw (81) having a respective axis of rotation (105), wherein the feeding device (999) is arranged in the vicinity of the feed screw (81), and wherein the continuous processing machine (80) is one of: a planetary extruder, a twin-screw mixer, an annular extruder, a single-screw extruder, a twin-screw extruder, a feed extruder for a fabric gluing calender, an extruder for a semi-finished product.

16. A method for feeding a continuous elongated element (900), said method comprising:

-providing a first roller (1) and a second roller (2) arranged side by side, the respective axes of rotation (101, 102) of which are substantially parallel to each other, wherein the first roller (1) is movable with respect to the second roller (2) along a displacement direction (103) so as to vary a mutual distance (D) between the axes of rotation (101, 102);

-arranging the continuous elongated element between the first roller (1) and the second roller (2);

-pushing the first roller (1) towards the second roller (2) with an adjustable thrust so as to nip the continuous elongated element (900) between the first roller (1) and the second roller (2);

-rotating the first roller (1) and the second roller (2) so as to advance the continuous elongated element (900) to feed the continuous elongated element (900) continuously at a feed speed to a feed point (A),

-controlling the respective rotation speed of the first roller (1) and of the second roller (2) so as to limit or prevent variations in the respective rotation speed due to the action exerted by the continuous elongated element (900) on at least one of the first roller (1) and the second roller (2).

17. A tyre production process comprising a method for feeding a continuous elongated element according to the preceding claim.