Apparatus for applying noise reducer elements to tyres for vehicle wheels

Abstract

Apparatus for applying noise reducing elements to tyres for vehicle wheels. The apparatus includes a loading station of stacks of noise reducing elements, an extraction station of noise reducing elements from each stack placed downstream of the loading station, and a conveyor placed downstream of the extraction station and extending along a predefined path. The conveyor is configured for supporting and advancing in a row the noise reducing elements extracted from the stacks which are then applied to a radially inner surface of the tyres. The extraction of each of the noise reducing elements contemplates: retaining a first noise reducing element placed at the base of a stack; raising the remaining noise reducing elements of the stack from the first noise reducing element; moving away the first noise reducing element according to a set path; and lowering the remaining noise reducing elements of the stack.

Claims

1. An apparatus for applying noise reducing elements to tyres for vehicle wheels, comprising: a loading conveyor arrangement configured for loading stacks of noise reducing elements; an extraction station for extracting noise reducing elements from each stack, wherein said extraction station is placed downstream of the loading station; and a supporting and advancing conveyor placed downstream of the extraction station and extended along a set path, wherein said supporting and advancing conveyor is configured for supporting and advancing in succession the noise reducing elements extracted from the stacks for subsequent picking up of the noise reducing elements from the supporting and advancing conveyor and applying of said noise reducing elements to a radially inner surface of at least one tyre for vehicle wheels, wherein said extraction station comprises: an extraction conveyor having an extraction conveyor upper transport surface configured for supporting at least one stack at a time, wherein said extraction conveyor upper transport surface is movable along a set direction, a retention device comprising first elongated engagement elements operatively active above the extraction conveyor upper transport surface and configured for retaining a first noise reducing element placed at the base of said at least one stack on the extraction conveyor upper transport surface, and a movement device comprising second elongated engagement elements operatively arranged above the extraction conveyor upper transport surface and configured for lifting or lowering remaining noise reducing elements of each stack.

2. The apparatus as claimed in claim 1, wherein the first elongated engagement elements comprise two first elements configured for acting on opposite sides of said first noise reducing element, and said two first elements face each other and are movable between a first mutual approached position, in which said two first elements act on said opposite sides of said first noise reducing element, and a second mutual moved-apart position, in which said two first elements are spaced from said opposite sides.

3. The apparatus as claimed in claim 2 wherein the second elongated engagement elements comprise two second elements configured for acting on opposite sides of at least one of the remaining noise reducing elements, and said second elements face each other and are movable between a first mutual approached position, in which said second elements act on said opposite sides of said at least one of the remaining noise reducing elements, and a second mutual moved-apart position, in which said two second elements are spaced from said opposite sides, said second elements being movable between a lowered position, close to the extraction conveyor upper transport surface, and a raised position.

4. The apparatus as claimed in claim 2, wherein each of the two first elements comprises a plurality of first elongated elements configured for at least partially penetrating into the noise reducing elements.

5. The apparatus as claimed in claim 3, wherein each of the two second elements comprises a plurality of second elongated elements configured for at least partially penetrating into the noise reducing elements.

6. The apparatus as claimed in claim 5, wherein the first elongated elements of each of the two first elements are alternated along the set direction with the second elongated elements of a respective second element placed on a same side.

7. The apparatus as claimed in claim 2, wherein each of the two first elements comprises a first support plate, and a plurality of first elongated elements projecting from the first support plate and located side by side along a first row.

8. The apparatus as claimed in claim 3, wherein each of the two second elements comprises a second support plate, and a plurality of second elongated elements projecting from the second support plate and located side by side along a second row, and wherein the first elongated elements are alternated with the second elongated elements, and said second support plate has through notches configured for receiving the first elongated elements.

9. The apparatus as claimed in claim 1, wherein the loading conveyor arrangement comprises a loading conveyor having a loading conveyor upper transport surface configured for supporting one plurality of stacks at a time, and said loading conveyor upper transport surface is movable along a set direction.

10. The apparatus as claimed in claim 9, wherein the loading conveyor arrangement comprises an auxiliary conveyor having a vertical transport surface extended alongside and along the loading conveyor upper transport surface and configured for receiving in abutment said plurality of stacks supported by the loading conveyor upper transport surface.

11. The apparatus as claimed in claim 10, comprising a lateral alignment station placed between the loading conveyor arrangement and the extraction station, wherein said lateral alignment station is configured for adjusting a lateral position of each stack with respect to a reference.

12. The apparatus as claimed in claim 11, wherein the lateral alignment station comprises an alignment conveyor having an alignment conveyor upper transport surface configured for supporting at least one stack, wherein said alignment conveyor upper transport surface is movable along a set direction, a vertical abutment surface available in a reference position above the alignment conveyor upper transport surface, and a pusher acting on top of the alignment conveyor upper transport surface and configured for pushing at least one stack against said vertical abutment surface.

13. The apparatus as claimed in claim 1, comprising a control device placed between the loading conveyor arrangement and the extraction station, wherein said control device is configured for verifying a vertical alignment of the noise reducing elements of each stack.

Description

DESCRIPTION OF THE DRAWINGS

(1) Such description is given hereinafter with reference to the accompanying drawings, provided only for illustrative and, therefore, non-limiting purposes, in which:

(2) FIG. 1 schematically shows a plant for building tyres for vehicle wheels comprising an apparatus for applying noise reducer elements to tyres for vehicle wheels according to the present invention;

(3) FIG. 2 shows a detailed top view of the apparatus for applying noise reducer elements in FIG. 1;

(4) FIG. 3 shows a lateral elevation view of the apparatus in FIG. 2;

(5) FIG. 4 shows an enlarged top view of a station of the apparatus in FIGS. 2 and 3;

(6) FIG. 5 show a front elevation view of a half of the station in FIG. 4;

(7) FIG. 6 show a lateral elevation view of some elements of the station in FIG. 4;

(8) FIGS. 7A-7I and 7L show respective operating configurations in the station shown in FIGS. 4, 5 and 6;

(9) FIG. 8 shows a radial half-section of a tyre built with the plant in FIG. 1;

(10) FIG. 9 shows the tyre in FIG. 8 sectioned along a middle plane; and

(11) FIG. 10 shows a perspective view of a noise reducer element configured for being installed in the tyre in FIG. 8.

DETAILED DESCRIPTION

(12) With reference to FIG. 1, reference numeral 1 identifies as a whole a plant for building tyres 2 for vehicle wheels.

(13) A tyre 2, built in said plant 1, is shown in FIG. 8 and essentially comprises a carcass structure 3 having two carcass plies 4a, 4b. An airtight layer of elastomeric material or so-called liner 5 is applied internally to the carcass ply/plies 4a, 4b. Two annular anchoring structures 6 comprising each a so-called bead core 6a bearing an elastomeric filler 6b in radially outer position are engaged to respective end flaps of the carcass ply or plies 4a, 4b. The annular anchoring structures 6 are integrated in the proximity of zones usually identified by the name of “beads” 7, at which the engagement between tyre 2 and a respective mounting rim usually occurs. A belt structure 8 comprising belt layers 8a, 8b is circumferentially applied around the carcass ply/plies 4a, 4b, and a tread band 9 is circumferentially overlapped to the belt structure 8. The belt structure 8 can be associated with so-called “under-belt inserts” 10 placed each between the carcass ply/plies 4a, 4b and one of the axially opposite end edges of the belt structure 8. Two sidewalls 11, extending each from the respective bead 7 to a corresponding lateral edge of the tread band 9, are applied in laterally opposite positions on the carcass plies 4a, 4b.

(14) Tyre 2 further comprises noise reducer elements 12 shaped as tiles, coupled to a radially inner surface of tyre 2 located at the tread band 9.

(15) The noise reducer elements 12 are placed astride of a middle plane “M” of tyre 2 and are arranged sequentially side by side, or slightly spaced apart, along the circumferential extension of tyre 2 itself (FIG. 9), in a number depending on the size of tyre 2.

(16) Such noise reducer elements 12 are made of a sound-absorbing material, such as a polymeric foam, preferably of an open cell material, more preferably of polyurethane foam. Their function is to attenuate the noise produced by tyre 2 itself during use.

(17) Each noise reducer element 12 may have a thickness “t” of between about 10 mm and about 40 mm, and a width “W” (measured parallel to an axis of rotation “X-X” of tyre 2) comprised between about 80 mm and about 200 mm.

(18) Plant 1 shown in FIG. 1 comprises a production line 13 of tyres 2 consisting of a building apparatus 14 of green tyres 2 and at least one moulding and vulcanisation unit 15 operatively arranged downstream of the building apparatus 14.

(19) In the non-limiting embodiment of plant 1 shown in FIG. 1, the building apparatus 14 comprises a carcass building line 16 at which forming drums, not shown, are moved between different stations of dispensing semi-finished products designed to form, on each building drum, a carcass sleeve comprising the carcass plies 4a, 4b, liner 5, the annular anchoring structures and possibly at least part of sidewalls 11.

(20) At the same time, in an outer sleeve building line 17, one or more auxiliary drums, not shown, are sequentially moved between different work stations designed to form an outer sleeve on each auxiliary drum, comprising at least the belt structure 8, the tread band 9, and possibly at least part of sidewalls 11.

(21) The building apparatus 14 further comprises an assembling station, not shown, at which the outer sleeve is coupled to the carcass sleeve.

(22) In other embodiments of plant 1, not shown, the building apparatus 14 may be of different type, for example designed to form all of the above components on a single drum by means of building devices.

(23) The built tyres 2 are then transferred to the moulding and vulcanisation unit 15.

(24) As shown in FIG. 1, an apparatus 18 for applying noise reducer elements 12 to tyres 2 is operatively located downstream of the moulding and vulcanisation unit 15.

(25) The moulded and vulcanised tyres 2 are moved, by suitable devices not shown, from the moulding and vulcanisation unit 15 into apparatus 18 for applying noise reducer elements 12.

(26) Apparatus 18 comprises a conveyor belt or a motorised roller 19 for feeding tyres 2 coming from the moulding and vulcanisation unit 15.

(27) In the vicinity of the motorised roller 19, apparatus 1 comprises a loading station 20 of stacks 21 of noise reducer elements 12, an extraction station 22 of said noise reducer elements 12 from each stack 21 placed downstream of the loading station 20, a conveyor 23 placed downstream of the extraction station 22 and extending along a predefined path. The conveyor 23 is configured for supporting and advancing in a succession the noise reducer elements 12 extracted from stacks 21. The loading station 20 acts as a buffer for the noise reducer elements 12.

(28) Each stack 21 may consist of a number of noise reducer elements 12 of between about twenty and about thirty. In the accompanying drawings, for the sake of clarity, each stack 21 comprises six or eight noise reducer elements 12.

(29) A station 24 is arranged at a terminal end of conveyor 23 for picking up the noise reducer elements 12 from conveyor 23 and applying said noise reducer elements 12 to the radially inner surface of tyres 2 carried by the motorised roller 19.

(30) Moreover, apparatus 18 comprises a lateral alignment station 25 placed between the loading station 20 and the extraction station 22, a control device 26 placed downstream of the loading station 20 and before the extraction station 22, a defective stack removal station 27 placed downstream of the control device 26.

(31) The extraction station 22 comprises a first conveyor 29 which has a first upper transport surface 30 configured for supporting at least one stack 21 at a time. The first conveyor 29 has a length comprised between about 300 mm and about 1000 mm. The first upper transport surface 30 is movable at steps along a predefined direction “D” at a speed of between about 20 m/min and about 60 m/min.

(32) In the embodiment shown, the first conveyor 29 is a first conveyor belt wrapped on rollers and the upper transport surface 30 is defined by an upper branch of said first conveyor belt.

(33) A retention device 31 is operatively active above the first upper transport surface 30 and is configured for retaining a first noise reducer element 12′ placed at the base of said at least one stack 21 on the first upper transport surface 30. Moreover, a movement device 32 is operatively arranged above the first upper transport surface 30 and is configured for lifting or lowering the remaining noise reducer elements 12 of each stack 21. The retention device 31 allows retaining the first noise reducer element 12′ resting thereon on the first conveyor 29 and raising the other overlying noise reducer elements 12 of the same stack 21 without the risk of dragging upwards also the first noise reducer element 12′ at the base.

(34) The retention device 31 comprises (FIGS. 4, 5, 6) two first support plates 33, each placed on one of the longitudinal sides of the first conveyor 29. Said two first support plates 33 and the devices moving them are substantially the same, whereby only one will be described hereinafter.

(35) The first support plate 33 carries a plurality of first elongated elements 34 projecting from said first support plate 33 towards the other first support plate 33. The first elongated elements 34 lie in a horizontal plane, are side by side and parallel to each other and are arranged along a first row.

(36) As shown in FIGS. 4-6, the first support plate 33 is connected to a first actuator 35. The first actuator 35 is configured for moving the first support plate 33 between a first approached position to the other first support plate 33 and a second moved-away position. The first actuator 35 is therefore is able to move the first support plate 33 and the first elongated elements 34 along a horizontal direction substantially parallel to the first elongated elements 34 and orthogonal to the predefined direction of the first conveyor 29. In the embodiment shown, the first actuator 35 comprises a first guide 36 on which a first slide 37 bearing the first support plate 33 translates. The first actuator 35 may for example be of the electro-mechanical or pneumatic type.

(37) The movement device 32 comprises two second support plates 38, each placed on one of the longitudinal sides of the first conveyor 29. Said two second support plates 38 and the devices moving them are substantially the same, whereby only one will be described hereinafter.

(38) The second support plate 38 carries a plurality of second elongated elements 39 projecting from said second support plate 38 towards the other second support plate 38. The second elongated elements 39 lie in a horizontal plane, are side by side and parallel to each other and are arranged along a second row.

(39) The first and second elongated elements 34, 39 are a sort of needles of such dimensions as to be able to penetrate into the sound-absorbing material and then exit therefrom without causing such damage to said sound-absorbing material as to impair the functionality thereof, once the noise reducer elements 12 are mounted into tyre 2.

(40) As shown in FIGS. 4-6, the second support plate 38 is connected to a second actuator 40 and to a third actuator 41.

(41) The second actuator 40 is able to move the second support plate 38 and the second elongated elements 39 along a horizontal direction substantially parallel to the second elongated elements 39 and orthogonal to the predefined direction of the first conveyor 29. In the embodiment shown, the second actuator 40 comprises a second guide 42 on which a second slide 43 bearing the second support plate 38 translates. The second actuator 40 may for example be of the electro-mechanical or pneumatic type.

(42) The third actuator 41 is configured for moving said second support plate 38 between a lowered position and a raised position. In the embodiment shown, the third actuator 41 comprises a third vertical guide 44 on which a third slide 45 bearing the second guide 42 is slidably mounted. The third actuator 41 is therefore able to move the second support plate 38 and the second elongated elements 39 along a vertical direction between the lowered position, in which the second elongated elements 39 lie at the same level of the first elongated elements 34, and the raised position, in which the seconds elongated elements 39 lie higher than the first elongated elements 34.

(43) The second support plate 38 has, on a lower edge thereof, through notches 46 (FIG. 6) configured for accommodating the first elongated elements 34 of the first support plate 33 when said second support plate 38 is in the lowered position (FIGS. 5 and 6, the second support plate 38 with the through notches 46 and the second elongated elements 39 are shown with dashed lines in the lowered position). The through notches 46 are formed between second adjacent elongated elements 39 and the first elongated elements 34 are vertically aligned with said through notches 46, i.e. staggered with respect to the second elongated elements 39. In other words, the first elongated elements 34 are alternated, along the predefined direction, with the second elongated elements 39. In this way, the first and second elongated elements 34, 39 may also engage simultaneously in the same first noise reducer element 12′, as will be described hereinafter.

(44) The first support plates 33 with the respective first elongated elements 34 are two first engagement elements configured for acting on opposite sides of said first noise reducer element 12′.

(45) The second support plates 38 with the respective second elongated elements 39 are two second engagement elements configured for acting on opposite sides of at least one of the remaining noise reducer elements 12.

(46) The extraction station 22 comprises two lateral partitions 47 positioned on opposite longitudinal sides of the first conveyor 29 for engaging against opposite sides of stack 21 positioned in the extraction station 22. Each of said two lateral partitions 47 has vertical slits 48 (shown in FIG. 4), each placed at one of the first or second elongated elements 34, 39. The first elongated elements 34 and the second elongated elements 39 pass in said vertical slits 48 and are free to slide therein during their movements. Said lateral partitions 47 have the function of preventing, during the extraction, the first elongated elements 34 and/or the second elongated elements 39 from remaining engaged in the noise reducer elements 12 themselves.

(47) The loading station 20 comprises: a second conveyor 49 having a second upper transport surface 50 configured for supporting a plurality of stacks 21 at a time. The second upper transport surface 50 is movable along a predefined direction for bringing stacks 21 towards the extraction station 22. In the embodiment shown, the second conveyor 49 is a second conveyor belt wrapped on rollers and the second upper transport surface 50 is defined by an upper branch of said second conveyor belt.

(48) The loading station 20 further comprises an auxiliary vertical conveyor 51 having a vertical transport surface 52 extending alongside and along the second upper transport surface 50. The auxiliary vertical conveyor 51 is also an auxiliary conveyor belt wrapped on rollers and the vertical surface 52 is defined by a branch of said auxiliary conveyor belt. The vertical surface 52 is configured for receiving a side of stacks 21 supported by the second upper transport surface 50 in abutment.

(49) The second conveyor 49 and the auxiliary conveyor 51 are preferably driven by a single motor, not shown and for example brushless, so as to impart the same transport speed to said two conveyors 49, 51.

(50) The second upper transport surface 50 and the vertical transport surface 52 therefore move jointly along the predefined direction and at a transport speed of between about 15 m/min and about 40 m/min. The second conveyor 49 and the auxiliary conveyor 51 have a length comprised between about 500 mm and about 2000 mm.

(51) The lateral alignment station 25 comprises a third conveyor 53 having a third upper transport surface 54 configured for supporting at least one stack 21 at a time, wherein said third upper transport surface 54 is movable along a predefined direction. The lateral alignment station 25 is configured for adjusting a lateral position of each stack 21 with respect to a reference. In the embodiment shown, the third conveyor 53 is a third conveyor belt wrapped on rollers and the third upper transport surface 54 is defined by an upper branch of said third conveyor belt. The third conveyor 53 has a length comprised between about 300 mm and about 600 mm. The third upper transport surface 54 moves in the predefined direction “D” at a transport speed of between about 15 m/min and about 40 m/min.

(52) A vertical abutment surface 55 is operationally active above the third upper transport surface 54 which is connected and moved by an actuator 56, preferably pneumatic, able to move it between a reference position, in which said vertical abutment surface 55 lies on the third upper transport surface 54, and a stand-by position, in which the vertical abutment surface 55 lies spaced apart from the third upper transport surface. The vertical abutment surface 55 and the relevant actuator 56 are placed at a longitudinal side of the third conveyor 53.

(53) A pusher 53 is positioned on the opposite longitudinal side of said third conveyor 53 acting above the third upper transport surface 54. Pusher 57 is connected and driven by a respective actuator 58, preferably pneumatic, and is configured for pushing at least one stack at a time against the vertical abutment surface 54 when the latter is in the reference position.

(54) The control device 26 is arranged between the lateral alignment station 25 and the subsequent defective stack 21 removal station 27 and is configured for checking the vertical alignment of the noise reducer elements of each stack 21. In one embodiment, the control device 26 comprises a photo-detector placed above stacks 21 passing between the lateral alignment station 25 and the subsequent removal station 27. The photo-detector is able to detect whether stacks 21 fall into a maximum predefined width.

(55) The defective stack 21 removal station 27 comprises a fourth conveyor 59 having a fourth upper transport surface 60 configured for supporting at least one stack 21 at a time. The fourth upper transport surface 60 can be moved along a predefined direction “D”.

(56) In the embodiment shown, the fourth conveyor 59 is a fourth conveyor belt wrapped on rollers and the fourth upper transport surface 60 is defined by an upper branch of said fourth conveyor belt. The fourth conveyor 59 has a length comprised between about 300 mm and about 600 mm. The fourth upper transport surface 60 moves in the predefined direction “D” at a transport speed of between about 15 m/min and about 40 m/min.

(57) Conveyor 23 placed downstream of the extraction station 21 comprises a fifth conveyor 67 having a fifth upper transport surface 68 configured for supporting the noise reducer elements 12 coming from the extraction station 21. The fifth conveyor 67 has a length comprised between about 300 mm and about 1000 mm. The fifth upper transport surface 68 moves in the predefined direction “D” at a transport speed of between about 15 m/min and about 40 m/min.

(58) A device, not shown, is optionally active on the fifth conveyor 67, which allows packing, or arranging against one another, the noise reducer elements 12 placed in a succession

(59) A control unit, not shown in the drawings, is operatively connected to the loading station 20, to the lateral alignment station 25, to the control device 26, to the extraction station 22, to conveyor 23, to the pick-up and application station 24 and to the motorised roller 19 in order to check them according to the process according to the invention.

(60) In use and according to the process according to the invention, tyres 2 extracted from the moulding and vulcanisation unit or units 15 are fed onto the motorised roller 19 and are advanced with an intermittent motion towards the terminal end of said motorised roller 19. One tyre 2 at a time is therefore carried on said terminal end.

(61) Meanwhile, an operator picks up a plurality of stacks 21 of noise reducer elements 12 from a bale, not shown, and manually loads them into the loading station 20, laying them onto the second conveyor 49 and pushing them against the auxiliary vertical conveyor 51. In particular, a first noise reducer element 12 placed at the base of each stack 21 is resting on the second upper transport surface 50 and one side of the same stack 12 is abutted against the second upper transport surface 52. Stacks 21 are therefore aligned in a row on the second conveyor 49. For example, the number of stacks 21 that may simultaneously lie in the loading station 20 is comprised between about ten and about thirty.

(62) The second conveyor 49 is advanced in the predefined direction “D” together with the third conveyor 53 by one step, up to arranging a stack 21 on the third upper transport surface 54. The third upper transport surface 54 is stopped and the lateral position of stack 21 placed in the lateral alignment station 25 is adjusted with respect to a reference. To this end, when stack 21 is already stationary on the third upper transport surface 54, the vertical abutment surface 55 is brought to the reference position (predefined according to the type of noise reducer elements 12 controlled at that time) that is usually already located in the vicinity of one side of stack 12. Thereafter, pusher 57 pushes stack 12 against said vertical abutment surface 55.

(63) Once the lateral alignment has been performed, the third conveyor 53 is advanced in the predefined direction “D” together with the fourth conveyor 59 by one step, up to arrange stack 21 on the fourth upper transport surface 60, or in the defective stack removal station 27. At the same time, a subsequent stack 21 is brought from the loading station 20 up to the lateral alignment station 25 to be subjected to the lateral alignment described above.

(64) During the transit between the third conveyor 53 and the fourth conveyor 59, stack 21 passes underneath the control device 26, which checks the vertical alignment of the noise reducer elements 12 belonging to such a stack 21, i.e. checks that all the noise reducer elements 12 are oriented in the same way and that stack 21 still has the shape of a right parallelepiped.

(65) In one embodiment, the control device 26 allows detecting the footprint of stack 21. For example, the control device 26 comprises a photo-detector which projects a vertical electromagnetic beam placed on a side of stack 21. If stack 21 is properly organised, the vertical electromagnetic beam does not intercept it and is not interrupted. If stack 21 has one or more elements 12 not organised, they intercept the vertical electromagnetic beam and the control device 26 detects the misalignment. The position of the electromagnetic beam may be adjusted according to the geometry of the noise reducer elements 12 controlled by apparatus 18.

(66) In the defective stack removal station 27, stack 21 is stopped again and if it does not meet the vertical alignment requirements detected before, an operator or an automated system can remove it.

(67) Once the vertical alignment has been checked, the fourth conveyor 59 is advanced in the predefined direction “D” together with the first conveyor 29 by one step, up to arrange stack 21 on the first upper transport surface 30, or in the extraction station 22. At the same time, a subsequent stack 21 is carried from the lateral alignment station 25 up to the defective stack removal station 27.

(68) With stack 21 stationary on the first upper transport surface 30, the single noise reducer elements 12 are extracted sequentially starting from the lowest one (FIGS. 7A-7I and 7L).

(69) To this end, stack 21 enters and stops in the extraction station 22 while the first elongated elements 34 of the retention device 31 are in the second mutual moved-apart position and also the second elongated elements 39 of the movement device 32 are in the second mutual moved-apart position and in the raised position (FIG. 7A). The first elongated elements 34 are positioned on opposite sides of the first noise reducer element 12 placed at the base of stack 21. The second elongated elements 39 are positioned on opposite sides of a second noise reducer element 12″ immediately above or in contact with the first noise reducer element 12′.

(70) The first elongated elements 34 are brought (by the first actuators 35) to the mutual approached position and partially inserted into the opposite sides of the first noise reducer element 12′ and the second elongated elements 39 are brought (by the second actuators 40) to the mutual approached position and partially inserted into the opposite sides of the second noise reducer element 12″ (FIG. 7B). In this way, the first noise reducer element 12′ is retained on the first upper transport surface 30.

(71) While the first noise reducer element 12′ is retained on the first upper transport surface 30, the second elongated elements 39 are moved to the raised position (by the third actuators 41) and they raise the second noise reducer element 12″ and all the other noise reducer elements 12 placed above (FIG. 7C).

(72) While the second noise reducer element 12″ is raised, the first elongated elements 34 are brought (by the first actuators 35) to the mutual moved-apart position and extracted from the opposite sides of the first noise reducer element 12′ (FIG. 7D).

(73) Thereafter, the first conveyor 29 is activated and the first upper transport surface 30 is advanced in the predefined direction “D” and according to the predetermined path together with the fifth upper transport surface 68 of the fifth conveyor 67. In this way, the first noise reducer element 12″ is extracted from stack 21, without sliding against the second noise reducer element 12″ or against other surfaces of apparatus 18, and is fed according to the predetermined path and towards the pick-up and application station 24 (FIG. 7E).

(74) Once the first noise reducer element 12′ has been moved away from the remaining noise reducer elements 12 of stack 21, the first upper transport surface 30 is stopped again. The second elongated elements 39, which are still inserted in the second noise reducer element 12″ and support it, are moved (by the third actuators 41) to the lowered position up to rest the second noise reducer element 12″ on the first upper transport surface 30 (FIG. 7F) and with the remaining noise reducer elements 12 of stack 21 resting on the second noise reducer element 12″.

(75) As described above, on each side, the first and second elongated elements 34, 39 are alternated (FIG. 7G) and the first elongated elements 34 are facing towards the through notches 46 of the first support plate 33 which carries the respective first elongated elements 34.

(76) The first elongated elements 34 are returned (by the first actuators 35) to the mutual approached position and inserted into opposite sides of the second noise reducer element 12″ (FIG. 7H). In this step, the first and second elongated elements 34, 39 co-exist within the second noise reducer element 12″. Notches 46 are placed astride of the first elongated elements 34.

(77) Thereafter, the second elongated elements 39 are extracted from the second noise reducer element 12″ (FIG. 7I), then raised to the raised position and partially inserted in the opposite sides of a third noise reducer element 12′″ (FIG. 7L). The cycle is then repeated until all the noise reducer elements 12 of stack 21 have finished. Thereafter, a subsequent stack 21 is moved to the extraction station 22.

(78) In an embodiment variant not shown, two or more stacks 21 at a time are inserted in the extraction station 22 (in a row and side by side), suitably sized, which simultaneously extracts two or more noise reducer elements at a time from the two or more stacks 21.

(79) The noise reducer elements 12 arranged in succession one after the other, can move forward, carried by the fifth upper transport surface 68, in groups, for example of three.

EXAMPLE

(80) Assuming that ten stacks 21 can be loaded at a time in the loading station 20, in which each stack 21 comprises thirty noise reducer elements 12 (for a total of three hundred noise reducer elements 12) and considering that the time required to pick up a noise reducer element 12 from conveyor 23 and apply it to a tyre 2 is about four seconds, the autonomy of the loading station 20 is about twenty minutes.