PROCESS AND APPARATUS TO FIND ONE END IN A TEXTILE FIBER BAND OR SLIVER AND TO ENGAGE SAID END TO FEED MEMBERS IN A TEXTILE MACHINE

Abstract: The apparatus acts on a textile fiber band or sliver (2) wound in a sliver can (3) to form primary coils helically aligned about the axis of said can to form superposed secondary coils. A grasping member (2) movable in a vertical direction raises some of said primary coils (4). A supporting member (17) is then moved close to one sliver length (28) descending from the raised coils (4) to arrange said length so that it may be disposed astride of the supporting member itself when said coils (4) are dropped into the can (3). Sliver (2) is unwound upon the action of an unwinding roller (20) or as a result of the rotation of the supporting roller (17) to bring the free end (2a) of said sliver close to the supporting member (17). The free end (2a) is engaged between the feed rollers (10, 11) of a textile machine by moving the supporting roller (17) close to said feed rollers or by moving the feed rollers close to each other.

Description: The present invention relates to a process and an apparatus to find one end in a textile fiber band or sliver and to engage said end to feed members in a textile machine, said sliver being collected in a sliver can and helically distributed to form primary coils consecutively aligned according to the form of a helix that is wound about the axis of said sliver can to form secondary coils consecutively superposed, said sliver ending at the top in a free end designed to be engaged to feed members in a textile machine. In particular the process and apparatus of the invention are conceived to automatically arrange a sliver so that it may undergo suitable processings by a textile machine of the type fed from a sliver can. It is known that for the treatment of textile fibers several operations are provided such as carding, combing, drawing and so on, which are adapted to select the fibers and arrange them so that they may undergo the subsequent spinning operations. To enable them to be submitted to these preliminary operations on the part of the corresponding textile machines, fibers must be arranged in the form of a continuous sliver and suitably collected within big cylindrical containers, usually referred to as "cans". During the processing by one of said textile machines, the sliver is proportionately drawn out of said cans upon the action of feed members associated with the machine and, after being submitted to the corresponding working operation, is laid down again in an orderly manner into other cans. From the last mentioned cans sliver will be fed to another textile machine designed to carry out the next working. At the present state of the art the presence of an operator is always necessary to achieve the initial engagement of the sliver to the textile machine members. In greater detail, the operator must find out the free end of the sliver in the can and then engage said end to the machine feed members. Once this operation is performed, the unwinding of the sliver from the can takes place automatically while the working is being carried out by the textile machine which will automatically stop if a lack of sliver between the feed members should be detected, due to the exhaustion of the sliver itself or the accidental breaking of the same. At this point it will be necessary to intervene manually again to restore the machine operation. The need of said interventions gives rise to some problems. In fact it has been found that, being a single operator generally entrusted with the control of an important number of textile machines, it may happen that the same is unable to promptly intervene so as to restore the operation of a machine which has stopped for one of the above specified reasons. It has been found as well that the necessity of said hand interventions makes it inconvenient to use modern automatized transferring techniques, by which it would be advantageously possible to achieve the transferring of cans to the different textile machines in a completely automatic manner. Presently said transferring operations are generally carried out by the same operators who are designed to restore the operation of the textile machines. A previous attempt to achieve the purpose of automatically feeding the free end of a fiber band or sliver to the feed members of a textile machine is discussed in the European Patent Application EP-A-0212979 published on March 4, 1907 in bulletin 87/10. The apparatus of this publication comprises a sliver lifter capable of grasping one free sliver end hanging down sideward from an upper portion of a full sliver can. In order to bring said free sliver end to the position adapted to enable it to be grasped by the sliver lifter, a turntable device is provided on which is put down the full sliver can having the free sliver end already arranged in a hanging down position so that said sliver lifter can pick up the latter while it passes in front of it by effect of the rotations imparted to the sliver can by the turntable device. However since this sliver lifter is not capable of performing its function of grasping one free sliver end without the aid of an auxiliary apparatus consisting of the turntable device, it is clear that the complete automation of the operation to find one end in a sliver and to engage said end to feed members of a textile machine cannot be considered as attained. The disadvantage resulting therefrom is therefore apparent if one takes into account the fact that in addition to the lack of a complete automation there is also the drawback that many operating components are required. Under this situation the main object of the present invention is to eliminate the problems present in the known art by providing an apparatus which, in a completely automatic manner, is capable of finding the free end of the sliver contained in a can and engaging said end between the feed members of a textile machine. The foregoing and further objects which will become more apparent in the course of the present description are substantially attained by a process to find one free end of a textile fiber band or sliver for engaging said free end to feed members of a textile machine, said sliver being collected in a sliver can and being helically distributed to form primary slive coils consecutively aligned, said process comprising the following steps: a) grasping and lifting upwards at least one of said primary sliver coils from said slive can to cause the formation of two sliver lengths descending from said raised primary sliver coils; b) disposing a supporting member alongside one descending sliver length of said two descending sliver lengths for moving it apart with respect to the other descending length for getting said lengths astride of said supporting member; c) disengaging said raised primary sliver coils to achieve astride engagement of both said descending sliver lengths on said supporting member; d) engaging said slive to unwinding means acting in the vicinity of said supporting member; e) unwinding, by the action of said unwinding means,that descending sliver length that is located between said supporting member and said free sliver end until the latter comes close to said supporting member; f) transferring said free sliver end to said feed members so as to achieve the engagement with the latter. Such process is achieve by an apparatus to find one free end in a textile fiber band or sliver for engaging said free sliver end to feed members of a textile machine. said sliver being collected in a sliver can and being helically distributed to form primary coils consecutively aligned, said apparatus comprising: a grasping member movable from one raised position above said sliver can to a second lower position into said sliver can to engage at least one of said pimamry coils and lift the latter to its said first raised position, said grasping member being comprised of an aspirator provided with a downward facing suction mouth in order to cause the engaging and grasping of said at least one of said primary coils; a supporting member movable from a rest position in which it is spaced apart from said feed members to a working position in which it is disposed in the vicinity of said feed members and alongside one sliver length descending from said primary coils having two descending sliver lengths and raised by said grasping member; unwinding means cooperating with said supporting member to unwind the primary coils located between said supporting member and the free end of the sliver; stop means acting near said supporting member for breaking the action of said unwinding means when said free end comes close to said supporting member; engagement means operatively connected to said supporting members for engaging said free sliver end with said feed members; characterized in that, said supporting member is able to move said descending sliver length apart with respect to the other descending length for getting said lenghts astride of said supporting member. Further features and advantages will best be understood from the detailed description of a process to find the free end of a sliver and to engage said end to the feed members in a textile machine in accordance with the present invention, and of some preferred embodiments of an apparatus to put the process of the invention into practice. Said description will be given hereinafter by way of non-limiting example, with reference to the accompanying drawings, in which: Fig. 1 is a top view of a can containing a sliver distributed therein in an orderly manner; Fig. 2 is a diagrammatic top view of the movements carried out by the can and the members laying down the sliver thereinto to achieve the distribution of said sliver in an orderly manner; Fig. 3 is an interrupted sectional view, taken along line III-III in Fig. 4 in which the movable grasping member is shown, of the suction mouth exhibited by said grasping member associated with the apparatus of the invention; Fig. 4 is a diagrammatic side view of the apparatus in a rest condition, with the sliver being engaged between the feed members of a textile machine; Fig. 5 is a front view of the apparatus in the same conditions as in the preceding figure; Fig. 6 is a diagrammatic side view of the apparatus with the sliver guiding members spaced apart from the field of action of the other members of the apparatus; Fig. 7 is a side view of the apparatus with the grasping suction member lowered over the sliver contained in a can; Fig. 8 is a front view of the apparatus in a condition in which the grasping suction member has raised some primary coils formed with the sliver; Fig. 9 is a side view of the apparatus in a condition in which a supporting member has been arranged to engage a sliver length descending from the raised coils; Fig. 10 is a side view of the apparatus after the raised coils have fallen back into the can; Fig. 11 is a side view of the apparatus in a condition in which the unwinding member cooperates with the supporting member to find out the free end of the sliver; Fig. 12 is a side view of the apparatus in a condition in which the free end of the sliver has reached the supporting member; Fig. 13 is a side view of the apparatus in a condition in which the supporting member is raised to engage the free end of the sliver to the feed members of the textile machine; Fig. 14 is a side view of a further possible embodiment of the apparatus in question where the members thereof are disposed in a rest condition and the sliver is engaged by the feed members of the textile machine; Fig. 15 is a front view of the apparatus in the same conditions as in Fig. 14; Fig. 16 is a side view of the apparatus shown in Fig. 14 where the members designed to guide the sliver are moved away from the field of action of the other members of the apparatus; Fig. 17 shows the apparatus as seen in Fig. 14 with the grasping suction member lowered over the sliver contained in a can; Fig. 18 is a front view of the apparatus shown in Fig. 14 in a condition in which the grasping suction member has raised some coils formed with the sliver; Fig. 19 is a side view of the apparatus shown in Fig. 18 in a condition in which a supporting member has been disposed alongside a sliver length descending from the raised coils; Fig. 20 is a side view of the apparatus after the coils have fallen back into the can; Fig. 21 is a side view of the apparatus as shown in the preceding figure, with an unwinding member cooperating with the supporting member to carry out the search of the free sliver end; Fig. 22 shows the apparatus viewed in Fig. 14 with the free sliver end disposed close to the supporting member; Fig. 23 is a side view of the apparatus shown in Fig. 14 with the free sliver end being engaged between the feed members of the textile machine; Fig. 24 is a side view showing a further embodiment of the apparatus in a rest condition with the sliver engaged between the feed members of the textile machine; Fig. 25 is a front view of the apparatus as viewed in Fig. 24; Fig. 26 is a side view of the apparatus shown in Fig. 24 in a condition in which the members designed to guide the sliver are spaced apart from the field of action of the other members of the apparatus; Fig. 27 is a side view of the apparatus shown in Fig. 24 with the grasping suction member lowered over the sliver contained in a can; Fig. 28 is a front view of the apparatus as viewed in the preceding figure in a condition in which the grasping suction member has caused the raising of some coils formed with the sliver; Fig. 29 is a side view of the apparatus as shown in Fig. 28 in a condition in which a supporting member has been disposed alongside a sliver length descending from the raised coils; Fig. 30 is a side view of the apparatus with the sliver being engaged on either side of the supporting member; Fig. 31 shows the apparatus in a condition in which the sliver is unwound in order to find out the free end; Fig. 32 is a side view of the apparatus with the free sliver end being engaged in the region of the supporting member; Fig. 33 shows the apparatus as viewed in the preceding figure when the free end is engaged between the feed members of a textile machine. Referring particularly to Figs. 4 to 13, reference numeral 1 globally denotes an apparatus capable of carrying out a process adapted to find one end in a textile fiber band or sliver and engage said end to the feed members of a textile machine in accordance with the present invention. Apparatus 1 is designed to act on a sliver 2 which, as clearly seen in Fig. 1, is conventionally arranged in an orderly manner at the inside of a cylindrical container or can 3. In greater detail, sliver 2 is helically wound so as to form a number of primary coils 4 consecutively aligned according to the form of a helix that is wound about the axis of can 3. The helical distribution of primary coils 4 forms a number of consecutively superposed secondary coils, one of which is disposed over all the other coils, as seen in Fig. 1, and terminates in a free end 2a of sliver 2. In a manner known per se, the distribution of sliver 2 at the inside of can 3 is the result of the combination of two rotational movements. One of said movements is given by the rotation of can 3 about is own axis in the direction of arrow 5 in Fig. 2 upon the action of a device referred to as "can-turning device". Said rotation of can 3 causes the formation of superposed secondary coils. A second rotational movement is given by a circular path 6 which is eccentric to can 3, taken in the direction of arrow 7 in Fig. 2 by a so-called "mouth" 8 designed to lay down said sliver 2. The second movement, controlled by a device named "mouth-turning device" gives rise to the formation of the primary coils 4. As clearly seen in Figs. 4 to 13, can 3 containing sliver 2 is arranged underneath the apparatus 1 the members of which cooperate with the feed members 9 of a textile machine, not shown, to achieve the engagement of the free end 2a of sliver 2 between said feed members. In the embodiment shown feed members 9 consist of an idler feed roller 10 and a powered feed roller 11 disposed alongside each other. The search of the free end 2a and the engagement thereof between the feed members 9 take place, according to the present invention, by means of a process comprising the following steps: lifting at least one of said primary coils from the sliver can to cause the formation of two sliver lengths descending from the raised coils; disposing a supporting member alongside one of said descending lengths to move it apart with respect to the other descending length and arrange it so that it engages on either side of the supporting member due to the downward movement of the raised coils; disengaging the raised coils to achieve the engagement of the length descending on either side of the supporting member; engaging the sliver to unwinding means acting in the vicinity of the supporting member; unwinding, by the action of said unwinding means, the primary coils located between the supporting member and the free end until said free end comes close to the supporting member; transferring the free end close to said feed members so as to achieve the engagement of said end with the latter. According to the invention apparatus 1 comprises a grasping member 12 slidably engaged to a supporting frame not shown movable in a substantially vertical direction from a first position in which it is raised above the can 3 to a second position in which, as shown in Fig. 7, it acts flush with the sliver 2 contained in the can to engage at least one of the primary coils 4. Preferably, the grasping member 12 is comprised of an aspirator 13 provided with a suction mouth 14 directed downwardly, where a vacuum is produced to achieve the engagement of primary coils 4. As clearly seen in Fig. 3, the suction mouth 14 substantially has a rectangular-profile tubular section inside which there is a grid-structured protection element 15 made of perforated plate, for example. Said protection element 15 extends transversely, a certain amount far from the free end 14a of the suction mouth and enables the suction of air through mouth 14 while preventing the fibers of sliver 2 from being sucked into the aspirator 13 when the engagement of the primary coils 4 takes place. Apparatus 1 further comprises a supporting member 16 movable from a rest position in which, as shown in fig. 4, it is spaced apart from the feed members 9, to a working position in which, as seen in Fig. 9, it is disposed in the vicinity of said feed members for the reasons to be clarified in the following. In the embodiment shown the supporting member 16 comprises a supporting roller 17 rotatably engaged to a first arm 18 oscillatably pivoted, at one end thereof, to the supporting frame of the apparatus to bring the supporting roller from a rest position to an operating position. The arrest of motion of arm 18 in the operating position takes place as a result of a contact between the supporting roller 17 and a locating roller 19 rotatably engaged underneath the feed rollers 10 and 11. When in its operating condition the supporting roller 17 cooperates with unwinding means to carry out the search of the free end 2a of sliver 2. Said unwinding means consists of a powered unwinding roller 20 supported at one end thereof by a second arm 21 the opposite end of which 21a is rotatably pivoted to the supporting frame of apparatus 1. Arm 21 enables the unwinding roller 20 to be brought from a rest position in which, as shown in Fig. 4, it is spaced apart from the supporting roller 17, to an operating position in which, as shown in Fig. 11, it acts against the supporting roller to carry out the search of the free end 2a. While the unwinding roller 20 is in operation, sliver 2 is suitably guided through a guide element 22 pivoted to the second end 18b of the first arm 18, adjacent the supporting roller 17. The unwinding means is interlocked to stop means for example consisting of a photoelectric switch 23 associated with the guide element 22 and acting in the region of the supporting roller 17 to stop the operation of the unwinding roller 20 when the free end 2a comes close to said supporting roller. Appartus 1 further comprises engagement means acting so as to cause the engagement of the free end 2a by feed members 9. Still referring to the embodiment shown in Figs. 4 to 13, said engagement means is achieved by making the first arm 18 in two portions telescopically engaged with each other. In greater detail, one portion 24 is oscillatably pivoted to the supporting frame of the apparatus while the second portion 25 carrying the supporting roller 17 is slidably engaged along the first portion 24. In accordance with the process of the invention, the operating cycle of apparatus 1 takes place as follows. During the regular operation of the textile machine, apparatus 1 is at rest, as viewed in Fig. 4. As seen in said figure, while sliver 2 is being proportionately unwound from can 3 upon the action of feed roller 10 and 11, aspirator 13 keeps a raised position with respect to the can itself and the supporting and unwinding rollers, 17 and 20 respectively, keep their respective rest positions. Under this situation sliver 2 is conventionally guided upstream of the feed rollers 10 and 11, by a supporting bar 26 holding the sliver over can 3 adjacent the axis thereof. Furthermore a sliver guiding member 27 substantially formed with two upright rods provided in the lower part thereof with portions having a diverging extension, acts close to the feed rollers 10, 11 to keep the sliver trued with respect to said rollers. Both the supporting bar 26 and sliver guiding member 27 are movable for example upon command of fluid-operated cylinders, along respective guiding elements not shown, to be moved away from the field of action of the members of apparatus 1 when the latter must carry out the engagement of the free end 2a to the feed members 9. In greater detail, the supporting bar 26 is movable from an operating position in which, as previously said with reference to Fig. 4, it is disposed over the can 3 adjacent the axis of the latter, to a rest position in which, as shown in Fig. 6 for example, it is moved apart from can 3, under the feed rollers 10 and 11 and the locating roller 19. The sliver guiding member 27 instead, is movable from an operating position in which, as viewed in fig. 4, is disposed in front of the feed rollers 10, 11, to a rest position in which, as shown in Fig. 6, it is raised with respect to the same. Operation of apparatus 1 preferably takes place upon command of photoelectric sensors acting in known manner close to the feed rollers 10, 11 to cause the operating intervention of the apparatus itself when the absence of sliver 2 between said feed rollers 10, 11 is detected. Other sensors of known type act close to the can 3 to detect whether, when there is no sliver between the feed rollers, the can is completely empty or still contains a certain amount of sliver. If the can is empty, apparatus 1 is not operated until the empty can is replaced with a full can. According to the operating intervention of apparatus 1, after the supporting bar 26 and sliver guiding member 27 have been brought back to their respective rest positions, there is the activation of aspirator 13 which is brought, as shown in Fig. 7, from its first to its second position so that the suction mouth 14 rests on some primary coils 4 being part of the uppermost secondary coil. The arrest of the descending motion of aspirator 13 can be for example achieved upon command of a photoelectric switch associated with the suction mouth 14 or upon command of sensors designed to detect the level of sliver 2 contained in can 3. It will be recognized that the suction mouth 14 rests on some primary coils 4 at randon and that, according to the different cases, said coils may be located more or less spaced apart from the free end 2a. However the primary coils 4 engaged by the suction mouth 14 are included in the last secondary coil disposed at the top of the sliver mass contained in can 3. The primary coils on which the suction mouth 14 rests are immediately sucked against the stop element 15 and held sideways by the walls of the suction mouth. Aspirator 13 is then lifted up from can 3 and brought to its first position so as to cause the raising of the primary coils 4 engaged by the suction mouth 14, as clearly shown in Figs. 8 and 9. The raising of the primary coils 4 brings about the formation of at least a sliver length descending from said coils. In greater detail, if the raised coils 4 are far enough from the free end 2a of sliver 2, there is the formation of a first descending length 28 connected to the sliver mass 2 extending in the lower part of can 3 and a second descending length 29 which is instead connected to the free end 2a of the sliver. If, on the contrary, the raised primary coils 4 are very close to end 2a, or if said end itself is raised together with the coils, there is the formation of the single descending length 28. Once the aspirator 13 has carried out the step designed to raise the primary coils 4 in the manner described above, the first arm 18 having its second portion 25 extended past the first portion 24 is rotated about its end 18a upon the action of a fluid-operated cylinder for example, to bring the supporting roller 17 from a rest position to an operating position. During its displacement the supporting roller 17 passes under the grasping member 12 and is then disposed alongside the first descending length 28 in order to cause the latter to be moved away from the raised coils 4 and to be engaged between the locating roller 19 and the supporting roller itself. It is to be noted that the first descending length 28 engaged by the supporting roller 17 is preferably disposed on the opposite side with respect to the end 2a, taking into account the raised primary coils 4. In this manner the engagement of sliver 2 by the supporting member 16 is ensured even if the free end 2a of the sliver is raised together with the primary coils 4. When the supporting roller 17 has reached its operating position, aspirator 13 is deactivated so as to cause the disengagement of the raised primary coils 4 which consequently fall back into can 3. Under this situation the first descending length 28 becomes engaged on either side of the supporting roller 17 (see Fig. 10). After this step, the second arm 21 is rotated about its pivoting end 21a upon the action of a fluid-operated cylinder for example, so as to bring the unwinding roller 20 to its operating position against the supporting roller 17. As shown in Fig. 11, at the end of this step sliver 2 is engaged between the supporting roller 17 and unwinding and locating rollers 20 and 19 respectively, as well as suitably supported by the guide element 22 pivoted on the free end of the first arm 18. The unwinding roller 20 is then rotated in the direction of arrow 30 in Fig. 11 and, by friction, it pulls along in rotation the supporting roller 17 and locating roller 19 as well. In this way, the unwinding of the primary coils 4 included between the supporting roller 17 and the free end 2a is carried out. Preferably the sliver which is unwound by rollers 20, 17 and 19 is simultaneously and proportionately laid down into an auxiliary container 31 arranged under the feed rollers 10 and 11 and disposed alongside of can 3. It may be also advantageously provided that during this step can 3 be rotated by known means so that the primary coils 4 which are being unwound should be always disposed under the unwinding and supporting rollers 20 and 17. The photoelectric switch 23 causes the arrest of the unwinding roller 20 and consequently the supporting and locating rollers 17 and 19 as soon as the free end 2a goes beyond the contact line between said unwinding and supporting rollers. Under this situation, as viewed in Fig. 12, the free end 2a will be held between the supporting roller 17 and locating roller 19 and directed upwardly. The second portion 25 of the first arm 18 is now moved towards the interior of the first portion 24 upon command of a fluid-operated cylinder for example, so as to raise the supporting roller 17 and bring it to a position in which, as shown in Fig. 13, it acts against the powered feed roller 11 and is very close to the idler feed roller 10. The free end 2a is involved in the movement of the supporting roller 17 and, at the end of the displacement of said roller, it is engaged in the area defined between the supporting roller and feed rollers 10, 11. The powered feed roller 11 is then rotated in the direction of arrow 32 in Fig. 13 and by friction it pulls along in rotation the idler feed roller 10 and supporting roller 17. The free end 2a is therefore compelled to pass between the feed rollers 10, 11 and as a result the feeding of sliver 2 to the textile machine is restored. The operating cycle of apparatus 1 is completed by causing the return of the different members thereof to their respective starting positions shown in Fig. 4. In greater detail, first an angular rotation of arms 18 and 21 occurs so as to move the respective unwinding and supporting rollers 20 and 17 away from the feed rollers 10, 11. Then the sliver guiding member 27 moves downwardly in front of the feed rollers 10, 11 and engages the sliver 2 upstream of the latter while, simultaneously, the supporting bar 26 is brought to its operating position to ensure a regular unwinding of sliver 2. Finally, the second portion 25 of arm 18 is drawn out of the first portion 24, which enables the supporting roller 17 to come back to its rest position. At the end of the operating cycle of the apparatus sliver 2 can be automatically unwound by the feed rollers 10, 11 as far as either an accidental breaking of the same or its exhaustion require a new intervention of apparatus 1. Figs. 14 to 23 show a further embodiment of the apparatus in accordance with the invention, globally identified by reference numeral 33. In said figures all members which have not been modified or replaced with respect to those of the first embodiment hereinbefore described have been allocated the same reference numerals and they will not be further described except when necessary. In said second embodiment the engagement means is not accomplished by the first arm 18 made of two telescopically-engaged portions, but provision is made for the idler feed roller 10 to be mounted on at least a lifting arm 34 oscillatably pivoted to the supporting structure of apparatus 1 or the textile machine frame. The lifting arm 34 can be rotated at an angle about its pivoting axis 34a to bring the feed roller 10 from an operating position in which, as shown in Fig. 14, it acts against the powered feed roller 11, to a rest position in which, as shown in fig. 19, it is spaced apart from said powered feed roller. Furthermore when the supporting roller 17 is disposed in its operating position, it acts against the powered feed roller 11 instead of against the locating roller 19, as provided in the preceding embodiment. When the supporting roller 17 is in its operating position the powered feed roller 11 is made rotatably idle, preferably upon the action of an electromagnetic clutch connecting it to the corresponding driving motor. In accordance with the operation of apparatus 33, as sequentially shown in Figs. 14 to 23, once the raising of some primary coils has occurred in the same manner as in the first embodiment, the idler feed roller 10 is brought to its rest position, due to the angular rotation imparted to the lifting arm 34, and the supporting roller 17 is moved to its operating position, i.e. against the powered feed roller 11, due to an angular rotation of the first arm 18. While moving from its rest position to its operating position, the supporting roller 17 takes a path which passes underneath aspirator 13, so as to move close to the first descending length 28 and separate it from the raised coils 4. In this manner, like in the above description, the descending length 34 is arranged to get engaged on either side of the supporting roller 17 when the raised primary coils 4 are dropped into the can 3. Once the engagement of sliver 2 astride of the supporting roller 17 is achieved, the unwinding roller 20 is brought to its operating position and rotated so that, by pulling along in rotation the supporting roller 17 and feed roller 11, it may cause the unwinding of the primary coils 4 included between the supporting roller and the free end 2a. As previously described, the rotation of the unwinding roller 20 and, as a result, that of the supporting and feed rollers 17 and 11, is in this case too stopped when the free end 2a goes beyond the contact line between the unwinding roller and supporting roller. At this point the lifting arm 34 is rotated about its pivoting point 34a to bring the idler feed roller 10 to its operating position. As clearly seen in Fig. 23, when the idler feed roller 10 reaches its operating position, the free end 2a is engaged between said idler roller and the powered feed roller 11. The unwinding and supporting rollers 20 and 17 are brought back to their respective rest positions and sliver 2, after being engaged by the supporting bar 26 and sliver guiding member 27, can be unwound by feed rollers 10, 11 while the textile machine is working. Figs. 24 to 33 show a further embodiment of the apparatus in accordance with the invention globally identified by reference numeral 35. In this case too all members which have not been modified or replaced with respect to the other embodiments have been allocated identical reference numerals and will not be hereinafter described except where necessary. Like in the previously described alternative embodiment, in apparatus 35 as well the idler feed roller 10 is supported by at least a lifting arm 34 and is movable from an operating position in which it acts against the powered feed roller 11 to a rest postion in which it is spaced apart from said powered roller. In the present alternative embodiment arms 18 and 21, as well as their respective supporting and unwinding rollers, 17 and 20 respectively, provided in the preceding embodiments are replaced by a single primary arm 36 having one end 36a rotatably pivoted to the supporting frame of apparatus 35 while the other end 36b supports a powered roller 37 in cantilevered fashion. In this case the arm 36 and roller 37 perform both functions of supporting member and unwinding means for the operation of the apparatus, as more clearly shown in the following. As previously described with reference to the first arm 18, arm 36 oscillates about the pivoting point of its end 36a to bring the powered roller 37 from a rest position in which it is spaced apart from the feed members 9 to an operating position in which it acts adjacent said members. When in it operating position, roller 37 acts against the powered feed roller 11 which is made idle for example upon the action of an electromagnetic clutch. Apparatus 35 further comprises an auxiliary supporting bar 39 mounted in cantilevered fashion to one end of a supporting arm 40 the opposite end 40a of which is rotatably pivoted to the primary arm 36. The supporting arm 40 is movable about its pivoting point, for example upon command of a fluid-operated cylinder, to bring the auxiliary supporting bar 39 from a first position in which, as shown in Fig. 29, it is arranged to be in vertical alignment with the powered roller 37 and disposed thereunder when the latter is in its operating position, to a second position in which, as shown in Fig. 31, it is sideways moved apart from the powered roller 37, on the opposite side with respect to the feed members 9. In accordance with the operation of apparatus 35, sequentially shown in Figs. 24 to 33, after the raising of the primary coils 4 has occurred, the primary arm 36 is rotated about its pivoting axis to bring the powered roller 37 to its operating position against the powered feed roller 11, which is made idle in the same manner as previously described. During its displacement the powered roller 37 comes alongside of the first descending length 28 and laterally separates it from the raised coils 4 pushing it against the feed roller 11. When the raised coils 4 are dropped into the can 3, the first descending length 28 engages on either side of the powered roller 37. Advantageously the presence of an auxiliary sliver guiding member 41 may be provided, which is supported in cantilevered fashion by the primary arm 36 and, as clearly seen in Fig. 25, has a U-shaped configuration in which the two ends are diverging. Said auxiliary member 41 is designed to engage the first descending length 28 when the raised primary coils 4 fall into the can 3, as shown in Figs. 29, 30, 31. The auxiliary supporting bar 39 which has been till now in its first position, is moved to its second position by an angular rotation imparted to the supporting arm 40. Under this situation the auxiliary supporting bar 39 engages the sliver 2 and supports it in the region of the axis of can 3, upstream of the powered roller 37. The powered roller 37 is then driven in rotation in the direction of arrow 42 in Fig. 31 and, as a result, it pulls along in rotation the feed roller 11 to produce the unwinding of the primary coils 4 included between the powered roller 37 and the free end 2a. During this unwinding step the sliver is suitably guided by the supporting bar 39 and the sliver guiding member 41 and, as it occurs in the previously described embodiments, it is proportionately laid down into the auxiliary container 31. Preferably the auxiliary supporting bar 39 is provided at its free end opposite the supporting arm 40, with a circular ridge 39a adapted to prevent sliver 2 from falling down during the unwinding. The rotation of the powered roller 37, and therefore the feed roller 11, is immediately stopped, for example upon command of a photoelectric switch 43 acting close to the auxiliary sliver guiding member 41, when the free end 2a reaches said powered roller. When rollers are stopped the free end 2a is held therebetween and directed upwardly so that it can be engaged between the powered feed roller 11 and idler feed roller 10 when the latter is brought back to its operating position. Once this operation has occurred, the different members of apparatus 35 sequentially take their respective starting positions and the textile machine begins working again while sliver 2 is being progressively unwound from can 3 upon the action of feed rollers 10, 11. The present invention attains the intended purposes. With the process and apparatus of the invention it is in fact possible to carry out in a completely automatic manner the search of the free end of the sliver gathered in a can and the engagement of said end between the feed members of a corresponding textile machine, in order to restore the operation of said machine. Thanks to the completely automatic accomplishment of these operations, the time necessary to bring the textile machine into operation again is relatively short and it is possible to eliminate the long down times present in the textile machines of the known art when the feeding of sliver is for example stopped, and at that moment the operator is unable to attend to its restauration at once. Furthermore and advantageously, due to the elimination of all hand operations, it is possible to greatly exploit modern automatic techniques in order to carry out the transferring of cans to the different textile machines.

Claims: 1. A process to find one free end (2a) of a textile fiber band or sliver (2) for engaging said free end to feed members (9) of a textile machine, said sliver (2) being collected in a sliver can (3) and being helically distributed to form primary sliver coils (4) consecutively aligned, said process comprising the fllowing steps: a) grasping and lifting upwards at one of said primary sliver coils (4) from said sliver can (3) to cause the formation of two sliver lengths (28, 29) descending from said raised primary sliver coils (4); b) disposing a supporting member (17, 37) alongside one descending sliver length (28) of said two descending sliver lengths (28, 29) for moving it apart with respect to the other descending length (29) for getting said lengths astride of said supporting member (17, 37); c) disengaging said raised primary sliver coils (4) to achieve astride engagement of both said descending sliver lengths on said supporting member (17, 37); d) engaging said sliver (2) to unwinding means (20, 37) acting in the vinicity of said supporting member (17; 37); e) unwinding, by the action ofr said unwinding means (20, 37), that descending sliver length (28) that is located between said supporting member (17, 37) and said free sliver end (2a) until the latter comes close to said supporting member (17, 37); f) transferring said free sliver end (2a) to said feed members (9) so as to achieve the engagement with the latter. 2. An apparatus to find one free end (2a) of a textile fiber band or sliver (2) for engaging said free sliver end to feed members (9) of a textile machine, said sliver (2) being collected in a sliver can (3) and bieng helically distributed to form primary coils (4) consecutively aligned, said apparatus comprising: a grasping member (12) movable from one raised position above said sliver can (3) to a second lower position into said sliver can (3) to engage at least one of said primary coils (4) and lift the latter to its said first raised position, said grasping member (12) being comprised of an aspirator (13) provided with a downward facing suction mouth (14) in order to cause the engaging and grasping of said at least one of said primary coils (4); a supporting member (17, 37) movable from a rest position in which it is spaced apart from said feed members (9) to a working position in which it is disposed in the vinicity of said feed members (9) and alongside one sliver length (28) descending from said primary coils (4) having two descending sliver lenghts (28, 29) and raised by said grasping member (12); unwinding means (20, 37) cooperating with said supporting member (17, 37) to unwind the primary coils (4) located between said supporting member and the free end (2a) of the sliver (2); stop means (23) acting near said supporting member (17, 37) for breaking the action of said unwinding means (20, 37) when said free end (2a) comes close to said supporting member (17, 37); engagement means (25, 34) operatively connected to said supporting member (17, 37) for engaging said free sliver end (2a) with said feed members (9); charaterized in that, said supporting member (17,37) is able to move said descending sliver lenght (28) apart with respect to the other descending lenght (29) for getting said lenghts (28,29) astride of said supporting member (17,37). 3. An apparatus according to claim 2, characterized in that said supporting member comprises at least a supporting roller (17) rotatably engaged in cantilevered fashion to a first arm (10) which is rotatably hinged at one (18a) of its ends and angularly oscillatable about its pivoting axis in order to bring the supporting roller (17) from said rest position to said working position, said supporting roller (17) when in its working position acting against a locating roller (19) rotatably engaged below the feed members (9); and a guide element (22) oscillatably hinged to said first arm (18) being provided for engaging said sliver (2) extending on either side of said supporting roller (17) and guiding said sliver upstream of the same supporting roller. 4. An apparatus according to claim 2, characterized in that said unwinding means comprises at least a powered unwinding roller (20) carried by a second arm (21) rotatably supported at one (21a) of its ends and angularly oscillatable to bring said unwinding roller from a rest position in which it is spaced apart from a supporting roller (17) of said supporting member to a working position in which it acts against said supporting roller to unwind said sliver (2) engaged on either side thereof. 5. An apparatus according to claim 2, characterized in that it further comprises an auxiliary container (31) located below said feed members (9) and disposed alongside said stationary sliver can (3) to collect the sliver (2) unwound by the action of the unwinding means (20, 37). 6. An apparatus according to claim 2, characterized in that said stop means comprises at least a photoelectric switch (23) operating in the region of said supporting member (17) to detect the absence of sliver (2) thereon. 7. An apparatus according to claim 2, characterized in that said engagement means comprises one arm (18) carrying said supporting member (17), said arm consisting of a first portion (24) having its end (18a) rotatably hinged and being angularly oscillatable to bring said sypporting member (17) from said rest position to said working position, and a second portion (25) telescopically guided along the first portion (24) and engaging said supporting member (17), said second portion (25) being movable towards the first portion (24) to cause the lifting of said supporting member (17) when the latter is in its working position so that it is brought into working engagement with said feed members (9). 8. An apparatus according to claim 2, characterized in that it further comprises a supporting bar (26) movable from a rest position in which it is laterally spaced apart from the sliver can (3) to a working position in which it is located over said can (3), adjacent the axis of the same, to support the sliver (2) as it is unwound from the can (3) by the action of said feed members (9). 9. An apparatus according to claim 2, characterized in that said engagement means comprises at least a lifting arm (34) rotatably hinged at one end thereof and at the other end rotatably engaging an idler feed roller (10) being part of said feed members (9), said lifting arm (34) being angularly oscillatable about its pivoting axis to bring said idler feed roller (10) from a rest position in which it is raised with respect to a powered feed roller (11) being part of said feed members (9) as well, to a working position in which said idler feed roller (10) acts against the powered feed roller (11). 10. An apparatus according to claim 3, characterized in that said supporting roller (17), when in its working position, acts against a feed roller (11) being part of said feed members (9), said feed roller (11) being powered when the apparatus (1) is inactive and being operatively disengageable from the respective driving motor so that it is made to idle during the operating intervening of the apparatus itself. 11. An apparatus according to claim 2, characterized in that both said supporting member and unwinding means consist of a primary arm (36) supporting a powered roller (37) in cantilevered fashion and being oscillatably hinged at one end (36a) thereof, to bring said powered roller from said rest position to said working position, when in its working position said powered roller (37) acting against a feed roller (11) of said feed members (9). 12. An apparatus according to claim 11, characterized in that hinged to said primary arm (36) is a supporting arm (40) carrying an auxiliary supporting bar (39) in cantilevered fashion and being oscillatable about its pivoting point (40a) on the primary arm (36) to bring the auxiliary supporting bar (39) from one position in which it is designed to be vertically aligned with the powered roller (37) and located thereunder when said powered roller is in its working postion, to a second position in which said auxiliary bar is laterally spaced apart from said powered roller (37) and located on the side opposite said feed members (9).

Inventors: CARBONETTO, PIER FRANCO, FRACASSI, UMBERTO
Applicants: S.P.A. PETTINATURA ITALIANA
Application year: 1988
Main classification: B65H67
IPC codes: D01H5, D01H9, D01H15