CONTINUOUS SPINNING SYSTEM FOR CONNECTING A PLURALITY OF CARDING MACHINES WITH A DRAWING FRAME

Abstract: A continuous spinning system for connecting a plurality of carding machines (1) with a drawing frame (2) by means of two can-transporting roller conveyors (61, 62) arranged along a row of the carding machines (1) to the drawing frame (2) and a can-feed conveyor (31) arranged upstream of the drawing frame (2) and connected with each of the can transporting roller conveyors (61, 62) in such a manner that a one direction­ al circulating path is formed between the carding machines (1) and the drawing frame (2). A full can (11b) delivered from the respective carding machine (1) is transferred onto the roller coveyor (61) and further to a roller conveyor (62) and finally to a supply position for the drawing frame (2) via the can-feed conveyor (31). An empty can (11a) discharged from the draw­ ing frame (2) is transferred onto the roller conveyor (61) and returned to the respective carding machine (1). A front end of a sliver in the full can newly deposited on the supply position is picked up from the can (11b) and fed to a drafting zone of the drawing frame (2) when one of supply cans (11c) in the supply position is exhausted.

Description: 1. Field of the Invention The present invention relates to a continuous spinning device connecting a plurality of carding machines with a drawing frame, in which the respective slivers delivered from each of the carding machines are supplied to the drawing frame for doubling the same. 2. Description of the Related Arts In the conventional continuous system of the above type, such as disclosed in Japanese Examined Patent Publication (Kokoku) No. 38-25172 or Utility model Publication (Kokoku) No. 46-34341, a sliver-transporting belt or a table is disposed upstream of a drawing frame, along which a plurality of carding machines are arranged in parallel to each other. Slivers delivered from the respective carding machines are directly laid onto the belt or the table and supplied to a draft zone of the drawing frame. Another type of the continuous spinning system for connecting a plurality of carding machines with a drawing frame is disclosed in Japanese Examined Patent Publication (Kokoku) No. 39-16220, in which a can filled with a sliver delivered from the respective carding machine is automatically conveyed to a supply position of the drawing frame. The former system, in which the sliver is directly fed to the drawing frame, has a drawback in that the cost of installation is high since a large number of carding machines are necessary corresponding to the number of slivers to be doubled by the drawing frame. In addition, since the productivity of the drawing frame is limited, an increase of the doubling number of the sliver results in a lower efficiency of the respective carding machine. For example, assuming the productivities of the drawing frame and the respective carding machine are 600 m/min and 150 m/min, respectively, and the doubling number of the slivers in the drawing frame is eight, the efficiency of the respective carding machine must be lowered by 50% to equalize the productivity thereof with that of the drawing frame. In addition, a serious problem arises in the above direct feed system regarding the quality of the final yarn, because, according to the direct feed system, a direction of the sliver formed in the carding machine is not reversed in the drawing frame and a plurality of front hooked fibers remains in a roving to be fed to a final drafting process in a ring spinning frame. It is well-known in the art that the front hooked fiber in the roving prevents smooth drafting and has an adverse influence on a resultant yarn quality. To solve the above problem of front hooked fiber in the roving, as disclosed in Japanese Examined Patent Publication (Kokoku) No. 40-25177, it is proposed that a full can filled with a sliver delivered from a first drawing frame be turned upside down to feed the sliver to a second drawing frame in a reverse direction to the usual manner. This, however, can not be yet practically utilized because of the complexty and high cost of the device. On the contrary, in the case of the aforesaid system according to Japanese Examined Patent Publication No. 30-16220, since the sliver delivered from a carding machine is once received in a can before being supplied to the drawing frame, the sliver direction is reversed when the sliver is supplied to the drawing frame, and, thus the above problem can be eliminated. This system, however, is far from attaining complete automation because, although the full can from the carding machine is automatically conveyed to the feed position of the drawing frame, the sliver in the can cannot be automatically supplied to the drawing frame. In addition, this system requires a large number of cans and a wide space for transporting and storing cans, to smoothly operate the whole system. CH-A-422,599 discloses a system which is characterised in that when a group of sliver cans supplied to a drawing frame has been practically exhausted, the drawing frame is temporarily brought to standstill. In the standstill condition, all the slivers in the respective exhausted cans are severed and the exhausted cans are manually replaced by new or fresh full cans. Thereafter, when the trailing end of the several slivers have been "pieced" or connected with the leading end of a fresh sliver, the drawing frame is restarted. Such an operation, when using the system and apparatus of CH-A-422,599 results in considerable down-time. In contrast, and as clearly defined in the characterised part of claim 1 as examined, the act of sliver "piecing" or connecting between the exhausted cans and the fresh cans is carried out sequentially on a "one can by one can basis" whilst the drawing frame is in continuous operation. The device of the present invention clearly defines a continuous sliver piecing operation which is conducted smoothly and effectively. SUMMARY OF THE INVENTION It is an object of the present invention to provide a continuous spinning device for connecting a plurality of carding machines with a drawing frame, in which the efficiency of the respective carding machine can be kept always at a higher level, and a sliver delivered from the carding machine can be automatically supplied to the drawing frame without a problem of hooked fibers due to the sliver feed direction in the drawing frame. The above object is achievable by a continuous spinning device for connecting a row of carding machines arranged in parallel to each other with a drawing frame incorporating an auto-leveler therein for controlling a thickness unevenness of the sliver, each of the carding machines being provided with an automatic can-exchanger in a delivery side thereof, comprising a can-transporting means extending along a row of the can-exchangers toward the upstream region of the drawing frame, and a U-shaped can-feed conveyor provided in a direct upstream region of the drawing frame, the can-transporting means and the can-feed conveyor being connected to each other so that a full can delivered from the carding machine and pushed out by the can-exchanger is transported by the can-transporting means to the can-feed conveyor, while an empty can discharged from the can-feed conveyor is returned by the can-transporting means to the can-exchanger, characterized in that the respective can-exchanger is provided with a sliver-cutting device for severing a continuous sliver filled in the full can from the carding machine and positioning a cut end of the sliver at an upper portion of the full can, and the drawing frame is provided with a sliver conveyor extending straightly upstream from a drafting zone of the drawing frame beyond the upperside of an arcuate portion of the can-feed conveyor; in that a can-turning device for rotating the full can about an axis thereof is provided at an inlet portion of the can-feed conveyor and a suction nozzle movable between a sliver-pick-up position defined in the vicinity of the upper portion of the full can deposited on the can-turning device and a sliver-transferring position defined above the sliver-pick-up position is provided for withdrawing the cut end of the sliver in the full can with the cooperation of the can-turning device; and in that a sliver-nipping and feeding device is provided for receiving the cut end of the sliver from the suction nozzle at the sliver-transferring position and supplying the same onto the sliver-feed conveyor. In one preferred embodiment, the can-transporting means comprises two roller conveyors, each being arranged in parallel to the other and extending upstream from the can-feed conveyor, and a can-transferring device provided between both the roller conveyors at an end thereof remote from the can-feed conveyor for transferring the can from one roller conveyor to the other, the row of carding machines being arranged along one of the roller conveyors. The can-turning device comprises a turn-table provided in the vicinity of the inlet portion of the can-feed conveyor, and a can-displacing mechanism for temporarily positioning the full can on the turn-table. The sliver-cutting device comprises a sliver-suppressing plate provided in an upper region of a push-out position defined adjacent to a sliver-delivery postion in the can-exchanger, and a can-push-out mechanism for pushing out the full can from the sliver-delivery position to the push-out position. The operation of the above device is as follows: When a can disposed at the sliver-delivery position has been filled with a sliver, the can-exchanger is made to operate to displace the full can therefrom onto the roller conveyor of the can-transporting means and, simultaneously, a new empty can is supplied to the sliver-delivery position, whereby the delivery of the sliver from the carding machine can be continued without interruption. During the displacement of the full can, continuity of the sliver in the full can from the carding machine is severed by the sliver-cutting device and the cut end thereof is laid on the top of the full can, while the full can on the can-transporting roller conveyor is conveyed to the can-feed conveyor. On the can-feed conveyor, the full can is first deposited on the turn-table in the can-turning device, then the suction nozzle is moved down to the sliver-pick-up position and starts sucking. Simultaneously therewith, the full can is made to rotate about its axis by means of the turn-table, whereby the cut end of the sliver in the full can is easily caught by the suction nozzle. After the rotation of the full can is stopped, the suction nozzle is returned to the sliver-transferring position while holding the cut end of the sliver, whereby the sliver end is withdrawn from the full can. Then, the sliver end is transferred to the sliver-nipping and feeding device and supplied onto the sliver conveyor, and further, to the drafting zone of the drawing frame. The respective supply can deposited at the respective supply position of the drawing frame is sequentially forwarded to the next supply position when the foremost preceding supply can has become almost empty, whereby the empty can is pushed out from the supply position on the can-feed conveyor onto the roller conveyor of the can-transporting means and returned to the can-exchanger of the respective carding machine. BRIEF DESCRIPTION OF THE DRAWINGS Other objects and advantages of the present invention will be apparent from the following description with reference to the drawings illustrating the preferred embodiments: Fig. 1 is a plan view of a device according to the present invention; Fig. 2 is an enlarged plan view of a part of the device shown in Fig. 1, illustrating an automatic can-exchanger; Fig. 3 is an enlarged plan view of a part of the device shown in Fig. 1, illustrating a can-feed conveyor; Fig. 4 is a side elevational view corresponding to Fig. 3; Fig. 5 is a further enlarged plan view illustrating a mechanism and an operation of a sliver-nipping and feeding device for feeding a sliver to a sliver conveyor; Fig. 6 is a side view corresponding to Fig. 5; Fig. 7 is an enlarged view of another embodiment of the sliver-nipping and feeding device; Fig. 8 is a sectional view of a suction nozzle; Fig. 9 is a sectional view of a turning and swinging mechanism for moving the suction nozzle; and Fig. 10 is a plan view of the mechanism shown in Fig. 9. DESCRIPTION OF THE PREFERRED EMBODIMENTS Figure. 1 illustrates a continuous spinning device for connecting a plurality of carding machine 1 (four in this embodiment) with one drawing frame 2. The carding machine is of an individually operable type well-known in the art and, therefore, a detailed description thereof is not given in this specification. The respective carding machine 1 is provided with an automatic can-exchanger 3 at the sliver delivery side, that is, directly downstream of the carding machine (in this regard, in this text, "downstream" and "upstream" are used with reference to a flow of a sliver). The can-exchanger is also well-known in the art as disclosed in Japanese Examined Patent Publication (Kokoku) Nos. 36-5170 and 40-5170 or Japanese Examined Utility Model Publication (Kokoku) No. 60-30275. A can-transporting means 4 of a roller conveyor type is installed in front of the can-exchangers 3 along a row of the carding machines 1. As shown in Fig. 2, a sliver-delivery device of the carding machine 1 comprises a coiler plate 5 supported by a coiler pillar 6, a coiler wheel 7 rotatably secured in a sliver delivery position by the coiler plate 5, and a turn table 9 rotatably disposed beneath the coiler 7. In Fig. 2, reference numerals 10 and 12 designate a waiting position of an empty can 11a and a push-out position of a full can 11b, respectively. The can-exchanger 3 has three air cylinders 13, 15, and 17. The first air cylinder 13 is provided with a hook 14 engageable with a bottom flange of the empty can 11a at a free end of a piston rod 13a thereof, by which the empty can 11a laid on the can-transporting means 4 is taken into the waiting position 10. The second air cylinder 15 is provided with a pusher member 16 at a free end of a piston rod 15a thereof for pushing out the full can 11b from the sliver delivery position 8 to the push-out position 12 and, in turn, pushing in the empty can 11a deposited at the waiting position 10 into the sliver-delivery position 8. The third air cylinder 17 is provided with a pusher member 18 at a free end of a piston rod 17a thereof for pushing out the full can 11b deposited at the push-out position 12 onto the can-transporting means 4. A plurality of photo-electric sensors are provided for controlling the operation of the can-exchanger 3. A first phototube 19 is utilized for detecting the absence of the can 11 at the waiting position 10. A second phototube 20 is utilized for detecting the presence of the full can 11b at a take-in position 21 defined on the can-transporting means 4 confronting the waiting position 10. A first pair of a projector 22a and a receiver 22b is used to detect the presence of a can at the position 21. A second pair of a projector 23a and receiver 23b is used to detect the absence of a can 11 in the vicinity of a discharge position 24 defined on the can-transporting conveyor 4 confronting the push-out position 12. The operation of the photo-electric sensors is as follows: When the phototube 19 detects the absence of an empty can 11a at the waiting position 10, the receiver 22b detects the can 11 at the push-out position 21, and, further, the phototube 20 detects that the can now at the position 21 is the empty can 11b, a roller conveyor 61 (described later) of the can-transporting means 4 is made to stop in a short time, and the air cylinder 13 is made to operate so that the empty can 11a at the position 21 is displaced to the waiting position 10. When the can 11 deposited at the sliver-delivery position 8 has been filled with the sliver, that is, the full can 11b has been formed, the air cylinder 15 is made to operate and project the piston rod 15a forward so that the empty can 11a at the waiting position 10 is pushed to the right in Fig. 2 into the sliver-delivery position 8, which, in turn, causes to the full can 11b at the sliver-delivery position to be removed therefrom to the push-out position 12. After the displacement of the full can 11b has been completed, if the received 23b detects the absence of a can 11 at the discharge position 24, the air cylinder 17 is made to operate and project the piston rod 17a forward so that the full can 11b at the push-out position 12 is pushed to the discharge position 24 on the can-transporting means 4. The can-exchanger 3 is provided with a sliver-cutting device 25, by which the cut end of the sliver is positioned at the uppermost portion of the full can 11b while hanging down from the periphery thereof. The sliver-cutting device 25 is also known, for example, in Japanese Unexamined Utility Model Publication No. 57-37958. This sliver-cutting device 25 comprises a sliver-suppressing plate 26 just above the push-out position 12, extending horizontally from the coiler plate 5. The full can 11b is displaced from the sliver-delivery position 8 to the push-out position 12 while the sliver layer projected from the can 11b slides on the back surface of the sliver-suppressing plate 26. The can used in this system is a so-called "spring-biased can", in which a sliver dish (not shown) is always biased upward by a spring (not shown) in the conventional manner. Therefore, in the empty can 11a deposited at the sliver-delivery position 8, the sliver dish is projected above the can body to be brought into contact with the back surface of the coiler plate 5, which sliver dish is gradually pressed down into the can body as the sliver is filled in the can. Accordingly, during the can exchange, a new sliver coming in to the empty can 11a is braked between the sliver dish and the coiler plate 5, which causes a sliver breakage between the full can 11b and the empty can 11a, whereby the cut end of the sliver is allowed to drop down slightly from the periphery of the full can 11b. Alternatively, a pair of cutting rollers or an air jet may be used above the coiler wheel. Further, a comb-type lever, a roller lever or a pair of scissors may utilized beneath the coiler wheel. Such sliver-cutting devices are disclosed in Japanese Examined Patent Publication (Kokoku) Nos. 38-15763 and 40-17087 or Japanese Examined Utility Model Publication (Kokoku) No. 40-2420. The drawing frame 2 is of the conventional one head and one delivery type and is provided with a continuous can-exchanger 27. Further, the drawing frame 2 is provided with an auto-leveler (not shown) for leveling a thickness unevenness of the sliver of both short and long periods. This type of auto-leveler is well-known in the art, e.g. disclosed in Japanese Examined Patent Publication (Kokoku) No. 60-12447 and, therefore, a description thereof is omitted in this specification. A sliver conveyor 28 horizontally extends upstream from a machine frame 29 of the drawing frame 2 for supplying the sliver to a drafting zone (not shown) of the drawing frame 2. A can-feed conveyor 30 of a U-shape in a plan view is provided beneath the sliver conveyor 28 in such a manner that an arcuate portion of the U crosses the sliver conveyor 28 and both straight portions of the U are arranged behind the sliver conveyor 28 along an axis thereof. At the furthest end of each of the straight portions of the can-feed conveyor 30, there is provided an inlet 30a and an exit 30b, respectively. The can-feed conveyor 30 comprises a can path 31, a can-moving device 32 arranged in the vicinity of the inlet 30a, and a roller conveyor 33 arranged on the can path 31 except for the neighbourhood of the inlet 30a. The can-moving device 32 comprises four arms 36 equi-angularly mounted on a vertical shaft 35 and a motor 37 for intermittently rotating the shaft 35 90 degrees at a time. As illustrated in Fig. 3, the arms 36 are disposed so that, when the arms 36 are stationary, a can-receive position 38 for the full can 11b conveyed by the can-transporting means 4 is caught between one pair of the adjacent arms 36 and a sliver-pick-up position 39 is caught between another pair of the adjacent arms 36. A can-turning device 40 is arranged at the sliver-pick-up position 39 for rotating the full can 11b about an axis thereof. The can-turning device 40 comprises a turn-table 41 rotatably mounted on the can path 31 and a motor (not shown) for driving the turn-table 41 slowly in the arrowed direction in accordance with a signal generated when one of the supply can 11c for the drawing frame 2 has been empty, to turn the full can 11b positioned on the turn table 41. Alternatively, the can-turning device 40 may comprise a plurality of rollers which circumferencially nip and drive the full can 11b. On the roller conveyor 33, a predetermined number of supply cans 11c are deposited at supply position A through E and at least one empty can 11a is disposed at a reserve position F. The number of the supply cans 11c at supply positions A through E corresponds to a doubling number of slivers processed in the drawing frame 2. Since the amounts of sliver stored in the supply can 11c initially differ from each other in such a manner that the last can 11c at the position A closest to the full can 11b is 100% full of sliver and the foremost can 11c at the position E has the least amount of sliver while the middle cans 11c at the positions B through D have, in order, a gradually decreased amount of sliver so that a so-called "tapered operation" can be carried out, the content in the supply can 11c occupying the position E is exhausted one by one as the sliver processing in the drawing frame 2 is continued, if the respective can 11c is forwarded to the succeeding position in the clockwise direction in Fig. 3 when one of the supply cans 11c is exhausted. The above roller conveyor 33 is positively driven at a required time by a motor-belt means (not shown), so that the supply can 11c is intermittently forwarded one by one as shown in the arrowed direction by the cooperation of rotation of the arm 36. A single sliver-pick-up device 42 is provided for picking up the end of the sliver from the full can 11b on the turn-table 41 on a one can by one can basis. This device 42 comprises a stand 34a installed in the center of the continuous can-exchanger 27, on which a turning mechanism 43 and a swinging mechanism 44 is mounted for moving a suction arm 45. At a free end of the suction arm 45, a suction nozzle 46 is secured in such a manner that the latter is communicated to a suction source (not shown) through a hollow portion of the former. As shown in Fig. 8, the suction nozzle 46 is pivoted at the tip end of the suction arm 45 and rotatable axially by means of a motor 153. A mouth of the suction nozzle 46 is covered with a wire mesh 152, on which the sliver end is held by suction and lifted to a sliver-transferring position defined above the sliver-pick-up position 39, as stated later. The search for a free end of the sliver dropping down from the periphery of the can 11b deposited at the sliver-pick-up position 39, i.e., on the turn-table 41 is carried out with the cooperation of a detecting means 150, such as a phototube, attached to the suction nozzle 46 (see Fig. 8) while the can 11b is rotated by means of the turn table 41. When the phototube 150 detects the sliver end, the turn table 41 is made to stop and the suction nozzle 46 takes hold of the sliver end. Thereafter, the nozzle 46 lifts up the sliver end and withdraws the sliver from the can 11b while holding the sliver end by suction. The root portion of the suction arm 45 is related to the swinging mechanism 44 mounted on a base 34. The suction arm 45 is turnable at a predetermined angle substantially in the horizontal plane passing through an upper position thereof by means of the turning mechanism 43. Further, the suction arm 45 is swingable at a predetermined angle substantially in the vertical plane between the lower position and the upper position. More specifically, as illustrated in Figs. 9 and 10, the turning mechanism 43 comprises a rotatable disc 101 and a motor 104 for driving the disc 101 through gears 102 and 103. The swinging mechanism 44 comprises a shaft 106 rotatably held by a pair of supports 105, 105 and a motor 109 for driving the shaft 106 through gears 107 and 108, on which shaft 106 is fixedly secured the root of the suction arm 45. A sliver-nipping and feeding device 47 for receiving a fresh sliver withdrawn from the full can 11b and supplying the same to the drawing frame 2 is provided immediately upstream of a pair of feed rollers 48a, 48b and a screw guide 49, both of which are secured on a frame of a sliver conveyor 28 extending backward from the back side of the drawing frame 2. The sliver-nipping and feeding device 47 is mounted on a stand 50 installed on a basement 34 in the central region of the continuous can-exchanger 27. On the side wall of the upper portion of the stand 50, a swing arm 52 is pivoted and rotated back and forth, by a motor 51, at a predetermined angle in a vertical plane. A nip roller 53 of a fixed position is rotatably secured at the upper end of the swing arm 52. To an opposite end of a shaft of the nip roller 53 is integrally fixed a friction roller 54 which, in turn, is engageable with another friction roller 55 fixedly mounted to an output shaft of a motor M1 when the swing arm 52 is in the sliver nip position shown in Fig. 4. This nip roller 53 is mated with a displaceable nip roller 56 rotatably mounted at the end of a swing lever 57 pivoted on the swing arm 52 as stated before. The swing lever 57 is made to reversibly rotate at a predetermined angle about a pivot thereof by a motor (not shown) connected thereto, whereby the displaceable nip roller 56 is engageable with and disengageable from the nip roller 53 of the fixed position. A detector 58 such as a phototube is provided for detecting the front end of the sliver lifted up from the full can 11b by the suction arm 45 on the stand 50 at a position above the nip roller 53 when the swing arm 52 occupies the sliver-transferring position as shown in Fig. 4. On the upper surface of the stand 50, a V-shaped guide 59 is secured for smoothly guiding the sliver during the reversing operation thereof to the can 11b. A receiving plate (not shown) for the sliver which is released from the suction arm 45 may be provided between the V-shaped guide 59 and the suction nozzle 46 disposed at the sliver-transferring position. As illustrated in Fig. 3, a friction roller 60 is arranged immediately upstream of the pair of feed rollers 48a, 48b provided on the rear side of the drawing frame 2 and is driven by the feed roller 48a through the conventional pulley-belt means. The sliver nipped by the pair of nip rollers 53 and 56 is forwarded by the normal rotation of the latter with the friction roller 54 coaxially fixed with the nip roller 53 being pressed onto the friction roller 60 when the nip roller 25 is moved to the sliver-feed position shown by an imaginary line in Fig. 4 due to rotation of the swing arm 52. On the other hand, the screw guide 49 is connected to a motor M2 through the conventional pulley-belt means so that the screw guide 49 makes one rotation as the fresh sliver is supplied between the feed rollers 48a, 48b, whereby the old slivers precedingly supplied to the feed roller 48a, 48b are transversely shifted by one pitch of the screw guide 49. The can-transporting means 4 comprises a pair of roller conveyors 61 and 62 extending in parallel to each other behind the can-feed conveyor 30. At the further ends of the pair of roller conveyors 61 and 62, there is provided a can-transferring device 63 for transferring the can 11 on one roller conveyor 61 to the other roller conveyor 62. The roller conveyor 61 is connected to the exit 30b of the can-feed conveyor 30 at one end of the former, and is driven by a motor (not shown) to convey the can 11 further from the can-feed conveyor 30. The other roller conveyor 62 is connected to the inlet 30a of the can-feed conveyor 30 at one end of the former, and is driven by a motor (not shown) to convey the can 11 toward the can-feeding conveyor 30. In the illustrated embodiment, the can-transferring device 63 is constituted by a roller conveyor, but it may be replaced by a swing arm similar to the arm 36 or a stationary guide arranged obliquely relative to the roller conveyor 61 or an air cylinder for pushing the can to the roller conveyor 62. In the vicinity of the front ends of the roller conveyors 61, 62, a bypass 64 is provided for connecting both the roller conveyors 61, 62. A can-returning device 65 is arranged in a region corresponding to the bypass 64, by which the can 11 is displaced from the roller conveyor 62 to the roller conveyor 61. The can-returning device 65 comprises an air cylinder 66 and moves the can 11 by pushing the same deposited on a can-return position 68 with a pushing member 67 secured at a free end of a piston rod 66a of the air cylinder 66. A plurality of sensors are provided for controlling the operation of the can-returning device 65. A pair of a projector 69a and a receiver 69b detects the presence of the can 11 at the can-return position 68. A phototube 70 discriminates the full can 11b from the empty can 11a now at the can-return position 68. A phototube 71 detects the presence of the full can 11b on the can-receive position 38. If the full can 11b is detected at the can-receive position 38 by the phototube 71, every can 11 arriving at the can-return position 68 is pushed therefrom to the roller conveyor 61 by means of the air cylinder 66. On the contrary, if the absence of a full can 11b is detected at the can-receive position 38, the full can 11b arriving at the can-return position 68 is forwarded to the can-receive position 38 and only the empty can 11a is pushed out from the can-return position 68 to the roller conveyor 61. Alternatively to the illustrated embodiment , the can-transporting means 4 may be constituted by a reversibly driven type single roller conveyor and may be controlled so that the full and empty cans are alternately deposited on this roller conveyor. In the continuous spinning device described above, when the can 11 deposited at the sliver-delivery position 8 has been filled with the sliver, the can-exchanging operation is carried out after the phototube 19 has detected the presence of the empty can 11a at the waiting position 10, so that the resultant full can 11b is pushed out onto the push-out position 12 and, instead, the full can 11a is supplied to the sliver-delivery position 8. As a result of this can exchanging operation, one end of the sliver portion traversed from the coiler wheel 7 and the full can 11b is nipped between the sliver dish of the empty can 11a and the coiler plate 5, and the other end thereof is nipped between the full can and the sliver suppressing plate 26. According to the succeeding rotation of the turn-table 9, the empty can 11a starts to rotate, whereby the sliver portion is severed from the fresh sliver on the empty can side and the cut end thereof hangs down from the top of the full can 11b. Then, after the receiver 23b has confirmed the absence of a can 11 at the discharge position 24 on the can-transporting means 4, the air cylinder 17 is made to operate to push out the full can 11b from the push-out position 12 to the discharge position 24. The discharged can 11b is conveyed in the arrowed direction in Fig. 1 by means of the roller conveyor 61, the can-transferring device 63 and the roller conveyor 62. When the receiver 69b detects that the full can 11b has arrived at the can-return position 68, and simultaneously the phototube 71 has detected the absence of the full can 11b at the can-receive position 68, the full can 11b arriving at the can-return position 68 is supplied onto the former position 38 according to the continuous rotation of the roller conveyor 62. On the contrary, when there is no full can 11b on the can-receive position 38, the roller conveyor 62 is temporarily made to stop, during which period the full can 11b deposited at the can-return position 68 is transferred onto the roller conveyor 61 through the bypass 64 by the action of the air cylinder 66. In general, the abovesaid can-returning operation can be eliminated or, at least, minimized when the total productivity of the carding machines 1 is balanced with that of the drawing frame 2. Alternatively, for the same purpose, a pool for the full can 11b may be provided between the can-return position 68 and the can-receive position 38. When exhaustion or substantial exhaustion of the sliver in the supply can 11c at the top position has been detected by a sensor (not shown), the arm 36 is made to rotate at an angle of 90° so that the full can 11b on the turn-table 41 is displaced onto the roller conveyor 33 and another full can 11b at the can-receive position 38 is displaced onto the turn-table 41. Simultaneously therewith, the roller conveyor 33 is made to rotate to discharge the empty can 11a at the foremost preceding position of the supply cans 11c therefrom onto the roller conveyor 61 and to forward the respective supply cans 11c at one pitch along the U-shaped path of the roller conveyor 33. When the 90° rotation of the arm 36 is completed and the full can 11b has been deposited on the turn-table 41, the search operation for the sliver end is carried out on this full can 11b. That is, according to a signal indicating the completion of the can-exchanging operation from a limit switch (not shown), the turning mechanism 43 is operated so that the suction arm 45 waiting at a waiting position shown by a solid line in Fig. 3 is turned counter-clockwise to an operating position shown by an imaginary line in Fig. 4 by means of the swinging mechanism 44. When the suction nozzle 46 of the suction arm 45 reaches the vicinity of the periphery of the full can 11b at the sliver-pick-up position, suction of the suction nozzle 46 is commenced. When the suction arm 45 arrives at the lower position to operate a limit switch (not shown), the turn-table 41 is made to rotate, which, in turn, rotates the full can 11b in the arrowed direction so that the front end of the sliver dropping down from the periphery of the can 11b is sucked and held on a wire mesh 152 covering a mouth of the suction nozzle 46. Upon detection of the sliver end by a detector 150 incorporated in the suction nozzle 46, the turn-table 41 is made to stop and, simultaneously therewith, the swinging mechanism 44 is operated so that the suction arm 45 is displaced from the lower position to the upper position, whereby the sliver is withdrawn from the full can 11b. When the suction arm 45 reaches the upper position, the turning mechanism 43 is again operated to make the suction arm 45 rotate in the clockwise direction in Fig. 3 and retreat to the position shown by a solid line. According to this operation, the sliver lifted up from the full can 11b can be introduced between the pair of nip rollers 53 and 56 of the sliver nipping and feeding device 47 waiting with both of the rollers 53, 56 separated from each other to form an opening there-between, as shown in Fig. 4. Next, when a detector 58 such as a phototube detects the sliver introduced between the nip rollers 53 and 56, a signal is generated therefrom to start a motor (not shown) to displace the nip roller 56 in the clockwise direction as shown in Fig. 4, whereby the rollers 53 and 56 engage with each other and nip the sliver therebetween. Upon the completion of the nipping of the sliver by the nip rollers 53 and 56, suction transmission to the suction nozzle 46 is interrupted, and the end portion of the sliver lifted by the suction nozzle 46 is dropped down on the protector (not shown). After releasing the sliver end from the suction nozzle 46, the motor m1 is made to rotate to reverse of the nip rollers 53, 56 through the friction rollers 55 and 54, whereby the sliver is returned to the full can 11b. The motor m1 is then made to stop immediately before the sliver end passes through the nip zone between the nip rollers 53, 56 by the action of the detector 58. According to this reversing of the nip rollers 53, 56, a length of the free end of the sliver extending out from the nip zone of the nip rollers 53, 56 becomes very short. The sliver nipping and feeding device 47 is maintained in the state wherein the nip rollers 53, 56 hold the sliver end until the next rotation of the can-displacing arm 33 is completed. When the supply can 11c in the foremost preceding position has become nearly empty and a tail end of the sliver is close to the feed rollers 48a and 48b, a signal is generated from a detector (not shown) for supplying a fresh sliver. According to this signal, the motor 51 is made to rotate to cause the swing arm 52 together with the nip rollers 53, 56 to displace forward from the nip position to a feed position. Because the length of the sliver end projected out from the nip rollers 53, 56 is very short, this portion of the sliver is kept straight without bending during the displacement. When the nip rollers 53, 56 arrive at the sliver-feeding position, the friction roller 54 coaxially fixed with the nip roller 53 is pressed onto the rotating friction roller 60, whereby the nip rollers 53, 56 are rotated in the normal direction so that the front end of the fresh sliver held thereby is forwarded between the feed rollers 48a, 48b. As the fresh sliver is nipped between the feed rollers 48a, 48b, the screw guide 49 arranged upstream thereof is caused to make one rotation by means of the motor M2 so that the older slivers now being processed are transversely displaced by one pitch of the screw guide 49. Generally speaking, since it is difficult to precisely match the front end of the fresh sliver with the tail end of the exhausting sliver, there may be a small gap or overlap between the two ends during the above operation, whereby the resultant sliver delivered from the drawing frame is liable to include a thicker or thinner portion corresponding to the lapped ends or the gap in the case of the conventional system. Such unevenness of the resultant sliver, however, can be avoided according to the present invention due to the provision of the auto-leveler. Once the sliver is caught between the nip of the feed rollers 48a and 48b, the sliver is released from the nip zone between the nip rollers 53 and 56 through the backward swing motion of the swing lever 57 caused by the motor (not shown), because this motion of the lever 57 causes, in turn, the disengagement of the nip roller 56 from the nip roller 53. Thus, the fresh sliver is continuously supplied to a vacant space of the screw guide 49 prepared by the transverse displacement of the older slivers. After the release of the fresh sliver from the nip rollers 53, 56, the swing arm 52 together with the nip rollers 53 and 56 is made to reverse from the feed position to the nip position through the action of the motor 51 and maintained in the latter position while the nip rollers 53 and 56 are separated from each other until the next sliver supply is needed. The abovesaid operations are repeated as the 90° rotation of the can-displacing arm 36 is completed, and one of the supply can 11c for the drawing frame 2 is exhausted. On the other hand, the empty can 11a and the full can 11b pushed onto the roller conveyor 61 of the can-transporting means 4 are conveyed toward the furthest end thereof. When the receiver 22b detects the presence of the can 11a or 11b at the take-in position 21 corresponding to the respective carding machine 1, the following operation is carried out. If the phototube 20 detects that the can arrived at the take-in position 21 is the empty can 11a and the phototube 19 detects the absence of a can at the waiting position 10, the roller conveyor 61 is temporarily made to stop, during which period the air cylinder 13 is made to operate to take the empty can 11a from the take-in position 21 into the waiting position 10. On the contrary, if the empty can 11a is already at the waiting position 10, or if the can at the take-in position 21 is the full can 11b, the roller conveyor 61 continues its rotation and the can 11a or 11b on the roller conveyor 61 is circulated along the can-transporting means 4. In Fig. 7, another embodiment of the sliver nipping and feeding device 47 is illustrated, in which, instead of a pair of simple nip rollers 53 and 56 of the above embodiment, a pair of nip rollers with aprons 53A and 56A, such as a tensor bar type, are utilized. Because the nip zone of the aproned nip rollers 53A and 56A is longer than that of the former embodiment, the sliver end waiting in the nip position while held between the pair of rollers can be perfectly concealed within the nip zone of the aproned nip rollers 53A and 56A so as not to damage the sliver end. Also, instead of the motor M1 and the friction roller 55 for the reversing of the nip roller 53, and the friction rollers 54 and 60 for forwarding the nip roller 53, a reversible motor (not shown) may be provided on the swing arm 52, by which the nip rollers 53 and 56 are rotatable in both of the normal and reverse directions through the usual pulley and belt means. Further, an element movable in a straight path may be utilized for carrying the nip rollers in place of the swing arm 52 of the preceding embodiment. In addition, the search for the sliver end may be carried out by means of a disc-like or bar-like suction nozzle which is positioned above the top of the rotating full can 11b in parallel thereto, provided the sliver end is prepared on the upper surface of the full can 11b. When the present inventive device is applied to a normal spinning process consisting of carding, first drawing, second drawing, roving and ring-spinning, a rear hooked fiber originated from the carding process is fed to a drafting mechanism of a ring spinning frame in the reversed state, that is, as a front hooked fiber, because the sliver direction is reversed between the every adjacent processes (in this case, four times). It is well-known to those skilled in the art that, in a final stage of drafting, that is, in the ring spinning process, the rear hooked fiber is more preferable than the front hooked fiber because a smooth drafting can be then expected. Since a can is utilized for temporarily receiving a sliver delivered from the carding machine, there is no need to Lower the productivity of the respective carding machine for the purpose of matching the same with that of the drawing frame, whereby the number of the carding machines constituting the system can be decreased.

Claims: A continuous spinning device for connecting a row of carding machines (1) arranged in parallel to each other with a drawing frame (2) incorporating therein an auto-leveller for controlling a thickness unevenness of the sliver, each of the carding machines (1) being provided with an automatic can-exchanger (3) in a delivery side thereof, comprising a can-transporting means (4) extending along a row of the can-exchanges (3) toward the upstream region of the drawing frame (2), and a U-shaped can-feed conveyor (30) provided in a direct upstream region of the drawing frame (2), the can-transporting means (4) and the can-feed conveyor (30) being connected to each other so that a full can (11b) delivered from the carding machine (1) and pushed out by the can-exchanger (3) is transported by the can-transporting means (4) to the can-feed conveyor (30), while an empty can (11a) discharged from the can-feed conveyor (30) is returned by the can-transporting means ( 4) to the can-exchanger (3), characterized in that the respective can-exchanger (3) is provided with a sliver-cutting device (25) for severing a continuous sliver filled in the full can (11b) from the carding machine (1) and exposing a cut end of the sliver at an upper portion of the full can (11b), and the drawing frame (2) is provided with a sliver conveyor (28) extending straight upstream from a drafting zone of the drawing frame (2) beyond the upperside of an arcuate portion of the can-feed conveyor (30); in that a can-turning device (40) for rotating the full can (11b) about an axis thereof is provided at an inlet portion of the can-feed conveyor (30) and a suction nozzle (46) movable between a sliver-pick-up position (39) defined in the vicinity of the upper portion of the full can (11b) deposited on the can-turning device (40) and a sliver-transferring position defined above the sliver-pick-up position (39) is provided for withdrawing the cut end of the sliver in the full can (11b) with the cooperation of the can-turning device (40); and in that a sliver-nipping and feeding device (47) is provided for receiving the cut end of the sliver from the suction nozzle (46) at the sliver-transferring position and supplying the same onto the sliver conveyor (28). A continuous spinning device as defined in claim 1 characterized in that the can-transporting means (4) comprises two roller conveyor (61, 62), each being arranged in parallel to the other and extending upstream from the can-feed conveyor (30) and a can-transferring device (63) provided between both the roller conveyors (61, 62) at an end thereof remote from the can-feed conveyor (30) for transferring the can (11) from one of the roller conveyors to the other, the row of the carding machines (1) being arranged along one of the roller conveyors (61, 62). A continuous spinning device as defined in claim 1 characterized in that the can-turning device (40) comprises a turn-table (41) provided in the vicinity of the inlet portion of the can-feed conveyor (30), and a can-displacing mechanism for temporarily positioning the full can on the turn-table (41). A continuous spinning device as defined in claim 1 characterized in that the sliver-cutting device (25) comprises a sliver-suppressing plate (26) provided in an upper region of a push-out position (12) defined adjacent to a sliver-deliver position (8) in the can-exchanger (3), and a can-push-out mechanism for pushing out the full can (11b) from the sliver-delivery position (8) to the push-out position (12). A continuous spinning device as defined in claim 2, characterized in that a can-returning device is arranged at an end, on the drawing frame side, of the pair of roller conveyors (61, 62) of the can-transporting means (4), for transferring the can (11) from one of the roller conveyors (61, 62) to the other. A continuous spinning device as defined in claim 1 characterized in that the suction nozzle (46) is secured on a free end of a suction arm (45) which, in turn, is movable by means of a swinging mechanism (44) and a turning mechanism (43) arranged in a region encircled by the can feed conveyor (30). A continuous spinning device as defined in claim 1, characterized in that the sliver-nipping and feeding device (47) comprises a pair of nip rollers (53, 56) displaceable between the sliver-transferring position and a rear end of the sliver conveyor, one of the nip rollers (56) being movable away from and close to the other for releasably nipping the front end of the fresh sliver; and means for detecting (58) the front end of the sliver.

Inventors: HIRAI, HARUMI, SHINKAI, KUNIO, TOMOTO, YOSHIJARU
Applicants: HOWA MACHINERY LIMITED
Application year: 1986
Main classification: B65H67
IPC codes: D01H9, D01H5, B65H67