EP2921577B1

EP2921577B1 - Draft device and spinning machine

Info

Publication number: EP2921577B1
Application number: EP15159590.7A
Authority: EP
Inventors: Akihiro Morita
Original assignee: Murata Machinery Ltd
Current assignee: Murata Machinery Ltd
Priority date: 2014-03-19
Filing date: 2015-03-18
Publication date: 2019-08-28
Anticipated expiration: 2035-03-18
Also published as: EP2921577A2; CN104928814B; EP2921577A3; JP2015178688A; CN104928814A

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention mainly relates to a fiber control member provided to a draft device and adapted to curve a fiber bundle to be drafted by pairs of draft rollers.

2. Description of the Related Art

When drafting a material having high content rate of short fibers, a fiber control member adapted to curve a transportation path of a sliver may be arranged between pairs of draft rollers arranged next to each other. By arranging the fiber control member, a drafted fiber (sliver) can be prevented from falling off the pairs of draft rollers. Furthermore, since a draft ratio (a ratio at which the fiber is stretched) can be set to be large by arranging the fiber control member, drafting can be performed using a thick sliver. In a case of using a thick sliver, procurement of materials is facilitated and production efficiency can be improved.
Japanese Patent Application Laid-open No. 2006-200069 (Patent Document 1) discloses a draft device provided with this type of fiber control member. Patent Document 1 discloses an art in which the fiber control member (a fiber travelling control member) is provided between a pair of back rollers and a pair of third rollers, or between the pair of back rollers and a pair of second rollers. Patent Document 1 also describes a configuration in which the fiber control member is formed into a shape of a rod-like cylinder and is attached to a main body frame.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide a fiber control member having a function to effectively remove the accumulated fly wastes.
This object is achieved by a draft device comprising a fiber control member according to claim 1.
The present invention is based on the finding that in conventional approaches, since the sliver is rubbed with the fiber control member when travelling, a certain amount of cotton waste or short fiber falls off, and thus fly wastes may accumulate in proximity to the fiber control member. Patent Document 1 merely discloses a function and a position of the fiber control member and does not describe how to remove the accumulated fly wastes.
According to the present invention, a fiber control member comprises a first end portion, a fiber bundle curving section adapted to curve a transportation path of a fiber bundle to be drafted by a draft device, the fiber bundle curving section being formed at the first end portion, a second end portion located opposite to the fiber bundle curving section, and a cutout formed at the second end portion, the cutout being cut out towards the first end portion.
Accordingly, since fly wastes generated at the time of drafting fall from the cutout, the fly wastes can be prevented from accumulating around the fiber control member and the draft rollers.
In the fiber control member, a width of the cutout preferably becomes smaller in a direction towards the first end portion.
Accordingly, the fly wastes are unlikely to hook onto the cutout, the fly wastes can be more reliably prevented from accumulating.
In the fiber control member, positions of the first end portions at end portions in a longitudinal direction are preferably closer to the second end portion than a position of the first end portion at the fiber bundle curving section.
Since both end portions of the fiber control member are located on a side far from the fiber bundle, the fly wastes can be prevented from accumulating in proximity to end portions of each of the fiber control member and the draft roller in the longitudinal direction.
The fiber control member is formed of a plate-like member having preferably a thickness of at least 1.6 mm and at most 2.0 mm.
By setting the thickness of the plate-like member within this range, a gap between the fiber control member and the draft roller can be large. Thus, since the fly wastes can be made to fall from the gap, the fly wastes can be prevented from accumulating.
According to the present invention, a draft device includes the above-described fiber control member, a draft roller adapted to draft the fiber bundle, and attachment grooves adapted to receive the fiber control member for holding the fiber control member.
Accordingly, since the fiber control member is held by merely inserting the fiber control member into the attachment grooves, the fiber control member can be easily attached/removed. Thus, even if the fly wastes have accumulated, the fly wastes can be promptly removed.
The draft device preferably includes a draft roller supporting section adapted to support the draft roller. The attachment grooves are formed in the draft roller supporting section.
Accordingly, by merely attaching the fiber control member to the attachment grooves, a positional relationship between the fiber control member and the draft roller can be appropriate. Furthermore, since the draft roller supporting section has a function to support the draft roller and a function to hold the fiber control member, the number of components can be reduced.
The draft device is preferably configured as follows. The draft roller includes a draft portion at a central portion in an axial direction, the axial direction being substantially perpendicular to a travelling direction of the fiber bundle, and small-diameter portions located at both sides to the draft portion in the axial direction. A width of the fiber bundle curving section is substantially same as a width of the draft portion of the draft roller. The end portions of the fiber control member in the longitudinal direction are arranged to be opposed to the small-diameter portions and are closer to the second end portion than the fiber bundle curving section.
Since the draft roller drafts the fiber bundle by merely the draft portion at the central portion, positions, which are opposed to the small-diameter portions, of the fiber control member can be located away from the fiber bundle, and the fly wastes can be prevented from accumulating in proximity to the end portions of the draft roller in the longitudinal direction.
The draft device is configured as follows. The draft device includes a plurality of pairs of the draft rollers arranged in a travelling direction of the fiber bundle between an upstream end and a downstream end of the draft device. Each of the plurality of pairs of the draft rollers includes a top roller and a bottom roller. The fiber control member is arranged between a first bottom roller arranged first from the upstream end of the draft device and a second bottom roller arranged second from the upstream end of the draft device.
Accordingly, a function of the fiber control member can be effectively exerted.
According to a second aspect of the present invention, a spinning machine includes the above-described draft device, a pneumatic spinning device, and a winding device. The pneumatic spinning device is adapted to twist the fiber bundle drafted by the draft device by airflow to produce a spun yarn. The winding device is adapted to wind the spun yarn fed from the pneumatic spinning device around a package.
Accordingly, the spinning machine in which the fly wastes are unlikely to accumulate and a yarn breakage is unlikely to occur can be realized.
In the spinning machine, an angle formed by an installation surface and a fiber bundle transporting direction of the draft device is preferably at least 45 degrees and at most 90 degrees.
In the above-described case, since the fly wastes are unlikely to fall under influence of gravity, the fly wastes are likely to accumulate on the fiber control member. Thus, in the spinning machine with the above-described configuration, an effect of the present application in which the fly wastes are made to fall from the cutout can be more effectively exerted.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front view illustrating an overall configuration of a fine spinning machine according to an embodiment of the present invention;
FIG. 2 is a side view illustrating a spinning unit;
FIG. 3 is a perspective view illustrating a state in which a fiber control member is to be attached to a draft device;
FIG. 4 is a perspective view illustrating a portion of the draft device;
FIG. 5 is a side cross-sectional view illustrating a portion of the draft device;
FIG. 6A is a front view illustrating the fiber control member;
FIG. 6B is a perspective view illustrating the fiber control member;
FIG. 7A is a front view illustrating an example of another shape of the fiber control member; and
FIG. 7B is a front view illustrating an example of further another shape of the fiber control member.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Next, a fine spinning machine (a spinning machine) according to an embodiment of the present invention will be described with reference to the accompanying drawings. A fine spinning machine 1 illustrated in FIG. 1 includes a large number of spinning units 2 arranged side by side, a yarn joining vehicle 3, a motor box 4, a blower box 95, and a machine control device 90.
The machine control device 90 is adapted to intensively control each component provided to the fine spinning machine 1. The machine control device 90 includes a monitor 91 and an input key 92. By an operator performing an appropriate operation with the input key 92, for example, a setting and/or a state of a specific spinning unit 2 or all of the spinning units 2 can be displayed on the monitor 91.
As illustrated in FIG. 2, each of the spinning units 2 includes a draft device 7, a pneumatic spinning device 9, a yarn accumulating device 14, and a winding device 70 arranged in this order from upstream towards downstream. "Upstream" and "downstream" in the present specification indicate upstream and downstream in a travelling (transporting) direction of a sliver 6 at the time of spinning, a fiber bundle 8, and a spun yarn 10. Each spinning unit 2 is adapted to spin the fiber bundle 8, which is fed from the draft device 7, by the pneumatic spinning device 9 to produce the spun yarn 10, and to wind the spun yarn 10 by the winding device 70 to form a package 45.
The draft device 7 is arranged in proximity to an upper end of a housing 5 of the fine spinning machine 1. The draft device 7 is adapted to draft (stretch) the sliver (a fiber bundle) 6 fed from a sliver case (not illustrated) via a sliver guide 20 until a thickness of the sliver 6 becomes a predetermined thickness. The fiber bundle 8 drafted by the draft device 7 is fed to the pneumatic spinning device 9. The draft device 7 will be described later in detail.
The pneumatic spinning device 9 is adapted to apply twists to the fiber bundle 8 fed from the draft device 7 to produce the spun yarn 10. In the present embodiment, a pneumatic spinning device adapted to apply twists to the fiber bundle 8 by use of whirling airflow is employed. Although detailed description and drawings are omitted, the pneumatic spinning device 9 specifically includes a fiber guiding section, a whirling airflow generating nozzle, and a hollow guide shaft body. The fiber guiding section is adapted to guide the fiber bundle 8 fed from the draft device 7 to a spinning chamber formed inside the pneumatic spinning device 9. The whirling airflow generating nozzle is arranged around a path of the fiber bundle 8 and is adapted to generate the whiling airflow in the spinning chamber. With the whirling airflow, a fiber end of the fiber bundle 8 inside the spinning chamber is inverted and whirled. The hollow guide shaft body is adapted to guide the spun yarn 10 that has been produced from the spinning chamber to outside the pneumatic spinning device 9.
A yarn quality measuring instrument 12 and a spinning sensor 13 are provided downstream of the pneumatic spinning device 9. The spun yarn 10 spun by the pneumatic spinning device 9 passes the yarn quality measuring instrument 12 and the spinning sensor 13.
The yarn quality measuring instrument 12 is adapted to monitor a thickness of the travelling spun yarn 10 with an optical sensor, which is not illustrated. When detecting a yarn defect (a portion of the spun yarn 10 having abnormality in thickness or the like) in the spun yarn 10, the yarn quality measuring instrument 12 transmits a yarn defect detection signal to a unit controller (not illustrated) . The yarn quality measuring instrument 12 is not limited to the optical sensor and may be a configuration in which the thickness of the spun yarn 10 is monitored by a capacitance sensor, for example. The yarn quality measuring instrument 12 may detect a foreign substance in the spun yarn 10 as a yarn defect.
The spinning sensor 13 is arranged immediately downstream of the yarn quality measuring instrument 12. The spinning sensor 13 is capable of detecting a tension of the spun yarn 10 between the pneumatic spinning device 9 and the yarn accumulating device 14. The spinning sensor 13 transmits the detected tension to the unit controller. The unit controller detects an abnormal portion such as a weak yarn by monitoring the tension detected by the spinning sensor 13.
The yarn accumulating device 14 is arranged downstream of the yarn quality measuring instrument 12 and the spinning sensor 13. As illustrated in FIG. 2, the yarn accumulating device 14 includes a yarn accumulating roller 15 and a motor 16 adapted to rotationally drive the yarn accumulating roller 15.
The yarn accumulating roller 15 is capable of temporarily accumulating the spun yarn 10 by winding a predetermined amount of the spun yarn 10 around an outer peripheral surface thereof. By rotating the yarn accumulating roller 15 at a predetermined rotational speed in a state in which the spun yarn 10 is wound around the outer peripheral surface thereof, the spun yarn 10 can be drawn from the pneumatic spinning device 9 at a predetermined speed and be transported to downstream. Furthermore, since the spun yarn 10 can be temporarily accumulated around the outer peripheral surface of the yarn accumulating roller 15, the yarn accumulating device 14 can function as a kind of buffer. Accordingly, a defect (a slackening of the spun yarn 10, for example) in which a spinning speed in the pneumatic spinning device 9 and a winding speed (a speed of the spun yarn 10 wound around the package 45) are not correspond to each other for some reason can be resolved.
A yarn guide 17 and the winding device 70 are arranged downstream of the yarn accumulating device 14. The winding device 70 includes a cradle arm 71 supported in a swingable manner about a support shaft 73. The cradle arm 71 is capable of supporting a bobbin 48 in a rotatable manner, around which the spun yarn 10 is to be wound.
The winding device 70 includes a winding drum (a contact roller) 72 and a traverse device 75. Furthermore, the winding device 70 includes a winding drum driving motor, which is not illustrated. When a driving force of the winding drum driving motor is transmitted, the winding drum 72 is rotated while being in contact with an outer peripheral surface of the bobbin 48 or an outer peripheral surface of the package 45. The traverse device 75 includes a traverse guide 76 capable of engaging with the spun yarn 10. The winding device 70 drives the winding drum 72 by the winding drum driving motor while reciprocating the traverse guide 76 by a drive means, which is not illustrated. Accordingly, the winding device 70 rotates the package 45 being in contact with the winding drum 72 and winds the spun yarn 10 around the package 45 while traversing the spun yarn 10.
As illustrated in FIGS. 1 and 2, the yarn joining vehicle 3 includes a yarn joining device 43, a suction pipe 44, and a suction mouth 46. After a yarn breakage or a yarn cut has occurred in a certain spinning unit 2, the yarn joining vehicle 3 travels to such a spinning unit 2 on a rail 41 and stops. The suction pipe 44 sucks and catches the spun yarn 10 fed from the pneumatic spinning device 9 and guides the caught spun yarn 10 to the yarn joining device 43 while vertically swinging with an axis as a center. The yarn joining device 43 joins the guided spun yarns 10 together.
Next, the draft device 7 will be described in detail with reference to FIG. 2. First, a draft roller provided to the draft device 7 will be described.
As illustrated in FIG. 2, the draft device 7 includes the tubular sliver guide 20 into which the fiber bundle 6 is introduced, and a plurality of pairs of draft rollers include bottom rollers and top rollers that are respectively facing each other. The bottom rollers are located on a back side (a lower side) of the fine spinning machine 1, and the top rollers are located on a front side (an upper side) of the fine spinning machine 1. The draft device 7 of the present embodiment is configured as a so-called four-wire draft device provided with a pair of back rollers, a pair of third rollers, a pair of middle rollers, and a pair of front rollers in this order from upstream. In the present embodiment, an angle formed by an installation surface of the fine spinning machine 1 (a horizontal surface) and a sliver transporting direction (a yarn path) of the draft device 7 is at least 45 degrees and at most 90 degrees.
A plurality of the top rollers are a back top-roller 21, a third top-roller 22, a middle top-roller 24 with an apron belt 23 provided, and a front top-roller 25 in this order from upstream. A plurality of the bottom rollers are a back bottom-roller 26, a third bottom-roller 27, a middle bottom-roller 28 with an apron belt 23 provided, and a front bottom-roller 29 in this order from upstream.
Each of the top rollers 21, 22, 24, and 25 is a roller of which outer peripheral surface is formed of an elastic member such as rubber or the like. Each of the top rollers 21, 22, 24, and 25 is supported in a rotatable manner with an axial line thereof as a center via bearings (not illustrated) or the like. Each of the bottom rollers 26, 27, 28, and 29 is a metallic roller and is adapted to be rotationally driven with an axial line thereof as a center.
The draft device 7 includes an urging means (not illustrated) adapted to urge each of the top rollers 21, 22, 24, and 25 towards the respectively opposing bottom rollers 26, 27, 28, and 29. Accordingly, the outer peripheral surfaces of the top rollers 21, 22, 24, and 25 respectively make contact with outer peripheral surfaces of the bottom rollers 26, 27, 28, and 29 in an elastic manner. By rotationally driving the bottom rollers 26, 27, 28, and 29 with this configuration, the top rollers 21, 22, 24, and 25 that respectively make contact with the bottom rollers 26, 27, 28, and 29 in an opposing manner are rotated accompanying the rotation of the bottom rollers.
The draft device 7 transports the fiber bundle 6 towards downstream by nipping (sandwiching) the fiber bundle 6 between the rotating top rollers 21, 22, 24, and 25 and the rotating bottom rollers 26, 27, 28, and 29. In the draft device 7, a configuration is made such that a pair of the draft rollers located more downstream is rotated faster. The fiber bundle 6 is thus stretched (drafted) while being transported between a pair of the draft rollers and a pair of the draft rollers, and accordingly thickness of the fiber bundle 6 becomes thinner as goes downstream.
By appropriately setting a rotational speed of each of the bottom rollers 26, 27, 28, and 29, a degree to which the fiber bundle 6 is drafted can be changed. Thus, the fiber bundle 8 drafted to a desired thickness can be fed to the pneumatic spinning device 9. Accordingly, the spun yarn 10 of a desired yarn count (thickness) can be spun in the pneumatic spinning device 9.
Next, a fiber control member 50 provided to the draft device 7 will be described with reference to FIGS. 3 through 6. FIGS. 3 through 5 are each a view illustrating only a portion around the back bottom-roller 26 and the third bottom-roller 27 of the draft roller.
As illustrated in FIG. 3 and the like, the back bottom-roller 26 is formed of a draft portion 26a and small-diameter portions (reduced-diameter portions) 26b. The draft portion 26a is located at a central portion of the back bottom-roller 26 in an axial direction thereof. As a whole, an outer diameter of the draft portion 26a is constant. The sliver 6 is drafted by sandwiching the sliver 6 with the draft portion 26a of the back bottom-roller 26 and a draft portion of the back top-roller 21.
The small-diameter portions 26b are portions respectively connected to both ends of the draft portion 26a in the axial direction. The small-diameter portions 26b are portions of which diameters become small and again become large as located away from the draft portion 26a. In a same manner, the third bottom-roller 27 is formed of a draft portion 27a and small-diameter portions 27b. Although not illustrated in drawings, the other bottom rollers 28, 29 are the same.
As illustrated in FIG. 3 and the like, the draft device 7 includes a draft roller supporting section 60. The draft roller supporting section 60 is formed of two wall- like members 60a and 60b arranged in an opposing manner with a predetermined interval therebetween. The wall- like members 60a and 60b are respectively adapted to hold both end portion of the bottom roller (specifically, the small-diameter portions 26b, the small-diameter portions 27b) . In the present embodiment, the wall-like member 60a adapted to hold the back bottom-roller 26 and the wall-like member 60a adapted to hold the third bottom-roller 27 are different. In a same manner, the wall-like member 60b adapted to hold the back bottom-roller 26 and the wall-like member 60b adapted to hold the third bottom-roller 27 are also different. The two wall-like members 60a may be integrated. The two wall-like members 60b may be integrated.
An attachment groove 61 is formed in each region in proximity to each portion of the wall- like members 60a and 60b where the back bottom-roller 26 is held. The attachment grooves 61 are formed to vertically cross an arrangement direction of the bottom rollers. The attachment grooves 61 may be formed in a member provided separately from the wall- like members 60a and 60b.
The fiber control member 50 is received and held by the attachment grooves 61. The fiber control member 50 is formed of a plate-like member of which thickness is, for example, from 1.6 mm to 2.0 mm. The fiber control member 50 is plated by hard chrome or the like to exert abrasion resistance.
The fiber control member 50 has a sliver curving section (a fiber bundle curving section) 51, a cutout 52, and lateral end portions 53 including attachment portions 53a. In the following description, as illustrated in FIG. 6A, a side on which the fiber control member 50 makes contact with the sliver 6 (a side in which the sliver curving section 51 is formed) may be referred to as a sliver side, and a side opposite thereto may be referred to an opposite-sliver side. Furthermore, the sliver side may be referred to as the first end portion, and the opposite-sliver side may be referred to as a second end portion.
The sliver curving section 51 is formed on the sliver side (the first end portion) of the fiber control member 50. The sliver curving section 51 is formed at a central portion (a portion between the lateral end portions 53 or where the end portions 53 are not formed) of the fiber control member 50 in a longitudinal direction thereof (an axial direction of the bottom rollers). A length of the sliver curving section 51 in the longitudinal direction thereof is substantially the same as the lengths of the draft portions 26a and 27a.
The sliver curving section 51 is a portion formed by folding the plate-like member a plurality of times so as to curve towards the back bottom-roller 26 (upstream in the transporting direction of the sliver 6). Since outer surfaces of the folded portions make contact with the sliver 6, the sliver curving section 51 curves a transportation path of the sliver 6 (FIG. 5). By providing the fiber control member 50, the sliver 6 can be prevented from falling off. Furthermore, even if a draft ratio is set to be large, the sliver 6 can be drafted by the draft device 7. A gap L (FIG. 5) between the sliver curving section 51 and the back bottom-roller 26 is preferably at least 1.2 mm and at most 2.0 mm.
As illustrated in FIGS. 6A and 6B, the cutout 52 is formed at the second end portion (the opposite-sliver side) by cutting out the plate-like member from the end portion on the opposite-sliver side towards the sliver side (in other words, to be close to the first end portion) . The cutout 52 is formed at the central portion of the fiber control member 50 in the longitudinal direction (the portion between the end portions 53 or where the end portions 53 are not formed) . A size (a width, a length) of the cutout 52 in a longitudinal direction thereof is smaller than a size of the sliver curving section 51 in the longitudinal direction. When a width of the cutout 52 on the opposite-sliver side is referred to as L1, and a width of the cutout 52 on the sliver side is referred to as L2, L1 is greater than L2. In other words, the width of the cutout 52 becomes smaller or decreases from the second end portion towards the first end portion (from the opposite-sliver side towards the sliver side) . In the present embodiment, a change rate of the width of the cutout 52 is substantially constant.
When the sliver transporting direction is at least 45 degrees and at most 90 degrees as in the present embodiment, as illustrated in FIG. 5, fly wastes generated at the time of drafting are unlikely to fall under influence of gravity and are likely to accumulate on the fiber control member 50 (around an inner side of a curved portion of the sliver curving section 51, in particular) . Since the cutout 52 is formed to the fiber control member 50 of the present embodiment, the fly wastes can be made to fall and are unlikely to be accumulated. Thus, while benefiting from an advantage (improvement in a draft speed) brought by increasing the sliver transporting speed, a disadvantage (a tendency of the fly wastes to accumulate) can be resolved.
The attachment portions 53a are respectively formed at the both lateral ends of the fiber control member 50 in the longitudinal direction. The sliver side portions 53b of the attachment portions 53a are located closer to the opposite-sliver side than the sliver curving section 51. Accordingly, the accumulated fly wastes can be made to fall from portions (recesses between the sliver curving section 51 and the attachment portions 53a, in particular) around the attachment portions 53a.
The sliver side portions 53b of the attachment portions 53a are located further on the sliver side than sliver side portions 53c of portions 53d of the end portions 53 between the sliver curving section 51 and the attachment portions 53a. Hemispherical protrusions 53e that slightly protrude in a thickness direction (see the arrow T in Fig. 6B) are formed on the attachment portions 53a.
As illustrated in FIG. 3, by inserting the attachment portions 53a into the attachment grooves 61, the fiber control member 50 is attached to the draft device 7. The widths of the attachment grooves 61 are nearly equal to thicknesses of the attachment portions 53a. The attachment portions 53a can be held by the draft roller supporting section 60 by merely being inserted into the attachment grooves 61. The hemispherical protrusions 53e are optional and may be formed so that the thickness of the attachment portions 53a is adjusted to the width of the attachment grooves 61. The hemispherical protrusions 53e may also be formed in a direction opposite to the illustrated direction.
For removing the fiber control member 50, an operator is merely required to grip and pull the fiber control member 50 upward, e.g. at the end portions 53. In this manner, by configuring the fiber control member 50 to be removable through a one-touch operation, even if the fly wastes are accumulated on the fiber control member 50, the fly wastes can be easily removed.
Next, a variant embodiment of the above-described embodiment will be described with reference to FIG. 7. In the description of the variant embodiment, a same reference numeral will be denoted on a same or similar member in the drawings as/with the above-described embodiment, and description may be omitted.
The above-described shape of the cutout 52 is an example, and may be appropriately modified. For example, as illustrated in FIG. 7A, the width of the cutout 52 may be constant. In this case, the cutout 52 may be easily formed.
Alternatively, as illustrated in FIG. 7B, a portion of the cutout 52 may be formed in an arc shape. In this case, accumulation of the fly wastes can be more reliably prevented by preventing the fly wastes from hooking onto the cutout 52.
As described above, the sliver curving section 51 that curves the transportation path of the sliver 6 drafted by the pairs of the draft rollers is formed at the end portion of the fiber control member 50 of the present embodiment. The portion where the sliver curving section 51 is formed (the end portion on the side where the sliver curving section 51 is formed) is referred to as the first end portion, and the portion (the end portion) located opposite to the sliver curving section 51 is referred to as the second end portion. The cutout 52 that has been cut out towards the first end portion is formed at the second end portion of the fiber control member 50.
Accordingly, since the fly wastes generated at the time of drafting fall from the cutout 52, the fly wastes can be prevented from accumulating around the fiber control member 50 and the draft roller. A yarn breakage that may occur in association with accumulation of the fly wastes thus can be prevented from occurring.
The width of the cutout 52 of the fiber control member 50 of the present embodiment becomes smaller or decreases in a direction towards the first end portion.
Accordingly, since the fly wastes are unlikely to hook onto the cutout 52, the fly wastes can be more reliably prevented from accumulating.
The attachment grooves 61 that receive the fiber control member 50 for holding the fiber control member 50 are formed in the draft device 7 of the present embodiment.
Accordingly, since the fiber control member 50 is held merely by being inserted into the attachment grooves 61, the fiber control member 50 can be easily attached/removed. Thus, even if the fly wastes accumulates, the fly wastes can be promptly removed.
A width of the sliver curving section 51 of the present embodiment is substantially the same as the widths of the draft portions 26a and 27a of the draft roller (specifically, the back bottom-roller 26 and the third bottom-roller 27). Portions, which are respectively opposed to the small-diameter portions 26b and 27b, of the end portions 53 of the fiber control member 50 are formed on a side further away from the sliver 6 than portions respectively opposed to the draft portions 26a and 27a.
The draft device 7 drafts the sliver 6 with the draft portions 26a, 27a at the central portion of the bottom rollers 26, 27. Thus, by locating positions of the end portions, which are opposed to the small-diameter portions 26b, 27b of the bottom rollers 26, 27, of the fiber control member 50 away from the sliver 6, the fly wastes can be prevented from accumulating in proximity to end portions of the bottom rollers 26, 27 in a longitudinal direction thereof.
Although preferable embodiments of the present invention are described above, the above-described configurations may be modified as follows, for example.
In the above-described embodiment, the fiber control member 50 is arranged between the back bottom-roller 26 and the third bottom-roller 27. However, the fiber control member 50 may be arranged between the third bottom-roller 27 and the middle bottom-roller 28.
The above-described arrangement of the top rollers and the bottom rollers of the draft device 7 is an example. A positional relationship between the top rollers and the bottom rollers, or the number of the pairs of the draft rollers may be appropriately modified.
A shape of the fiber control member 50 may be any, and may be appropriately modified. For example, the sliver curving section 51 is not limited to a shape formed by curving a plate-like member. Furthermore, the shape of the cutout 52 and a range in which the cutout 52 is formed are arbitrary, and the cutout 52 may be another shape other than the shapes described in the above-described embodiment and the variant embodiment.
A method of attaching the fiber control member 50 is not limited to a one-touch method of merely inserting, and may be a configuration to fix by a bolt or the like.

Claims

A draft device (7) comprising:
a plurality of pairs of the draft rollers arranged in a travelling direction of a fiber bundle (6) between an upstream end and a downstream end of the draft device (7), wherein each of the plurality of pairs of the draft rollers includes a top roller (21, 22, 24, 25) and a bottom roller (26, 27, 28, 29), and

a fiber control member (50), comprising:
a first end portion;

a fiber bundle curving section (51) adapted to curve a transportation path of the fiber bundle (6) to be drafted by a draft device (7), the fiber bundle curving section (51) being formed on the first end portion;

a second end portion located opposite to the fiber bundle curving section (51); and

a cutout (52) formed at the second end portion, the cutout (52) being cut out towards the first end portion,

characterized in that with the cutout fly wastes can be prevented from accumulating around the fiber control member and the draft rollers,

the draft device further comprises attachment grooves adapted to receive the fiber control member for holding the fiber control member and in that the fiber control member (50) is formed of a plate-like member and is arranged between a first bottom roller (26) arranged first from the upstream end of the draft device and a second bottom roller (27) arranged second from the upstream end of the draft device,

the fiber bundle curving section (51) is a portion formed by folding the plate-like member, and

the fiber control member (50) is arranged so that an outer surface of the folded portion of the fiber bundle curving section (51) makes contact with the fiber bundle (6), the fiber bundle curving section (51) thereby curving the transportation path of the fiber bundle (6) and wherein the fiber control member is preventing the fiber bundle from falling off.
The draft device (7) according to claim 1, wherein a width of the cutout (52) becomes smaller in a direction towards the first end portion.
The draft device (7) according to claim 1 or claim 2, wherein lateral ends of the first end portion in a longitudinal direction are closer to the second end portion than the fiber bundle curving section (51).
The draft device (7) according to any one of claim 1 through claim 3, wherein the plate-like member having a thickness of at least 1.6 mm and at most 2.0 mm.
The draft device (7) according to any one claim 1 through claim 4, comprising a draft roller supporting section (60) adapted to support the draft rollers, wherein the attachment grooves (61) are formed in the draft roller supporting section (60).
The draft device (7) according to any one claim 1 through claim 5, wherein the draft roller includes a draft portion (26a, 27a) located at a central portion in the longitudinal direction, the longitudinal direction being perpendicular to a travelling direction of the fiber bundle (6), and small-diameter portions (26b, 27b) located at both ends of the draft portion (26a, 27a),
a width of the fiber bundle curving section (51) is same as a width of the draft portion (26a, 27a), and
the end portions (53) of the fiber control member (50) in the longitudinal direction are arranged to be opposed to the small-diameter portions (26b, 27b).
A spinning machine (1) comprising:
the draft device (7) according to any one of claim 1 through claim 6;

a pneumatic spinning device (9) adapted to twist the fiber bundle (8) drafted by the draft device (7) by airflow to produce a spun yarn (10); and

a winding device (70) adapted to wind the spun yarn (10) fed from the pneumatic spinning device (9) around a package (45).
The spinning machine (1) according to claim 7, wherein an angle formed by an installation surface of the spinning machine (1) and a fiber bundle transporting direction of the draft device (7) is at least 45 degrees and at most 90 degrees.