Title of Invention

YARN TAIL CUTTING METHOD IN SPINNING MACHINE

Abstract During doffing, a ring rail (17) is stopped at a position that corresponds to a part of a spindle base (24b) that contacts a yarn tail cutting member (28). A spindle (11) is stopped in a state where yarn (Y) extending from a cop (38) to a traveler (T) is wound at a position below contacting part. When the spindle (11.) is stopped, the cop (38) is raised and removed from the spindle (11) using a doffing aevice (35) . The yarn tail cutting member (28) is raised together with the cop (38) until the cop (38) is raised to a predetermined point. The ring rail (17) is raised when the cop (38) is raised and removed from the spindle (1.1) using the doffing device (35). The yarn (Y) is held between the yarn Lai1 cutting member (28), which has separated from the cop (38), and the spindle base (24b). The yarn (Y) is cut with the cutter portion (30). Accordingly, the length of the yarn tail remaining at the spindle base is reduced, and the yarn tail is reliably cut (Fig. IB).
Full Text

YARN TAIL CUTTING METHOD IN SPINNING MACHINE
BACKGROUND OF THE INVENTION
The present invent i.on relates to a method for cutting a yarn tail in a spinning machine. Specifically, the spinning machines nclude ring spinning frames and ring twisting frames that are capable of lifting and lowering a yarn tail cutting member along a blade extending upward from a spindle base. A -'am tail cutt 1 ng member Includes a bobbin rece iviriy portion and a cutter portion located lower than the bobbin receiving portion. The yarn rail cutting member and the spindle base can hold (pinchi yarn extending from a cop to a traveler.
A spinning machi ie such as a ring spinning frame and a ring twisting frame is required to automatically replace a full bobbin with another bobbin. In other words, a spinning machine i s required to perform a process for replacing a bobbin ab :>ut which yarn has been wound with an empty bobbin. SpecificaLly, the spinning machine is required to automatically wind yarn about an empty bobbin when activated after the completion of the bobbin replacement. Therefore, she spinning machine _i s required to connect yarn connected to a roller part to a spindle while keeping the yarn passing through a traveler. Conventionally, to meet the requirement, a yarn tail cutting portion is provided at the spindle base, and a yarn tail winding portion is located below the yarn tai l cutting portion. After a bobbin becomes full, the ring rail is quickly lowered so that inclined winding is performed. Thereafter, the yarn is wound about the yarn tail winding portion. When removing the full cop from a spindle, yarn extending between the yarn tail winding portier and the full cop, or a yarn tail, is cut by the yarn tail cutting portion. According to this method, yarn tail

is wound several times about the yarn tail winding portion at the tine of doffing. Thus, after the doffing, a large amount of yarn remai.ru-: on the yarn rail winding portion (spindle base).
Japanese Laid-Open Patent Publication No. 2002-173837 discloses a yarn tail cutting method for cutting yarn (yarn tail1 remaining on a spindle base. A yarn tail cutting member can, a cutter portion located below a bobbin receiving portion. The yarn tail cutting member can be raised and lowered along a blade extending upward from the spindle base. The yarn tail cutting member and the spindle base can hold (pinch) yarn extending from a coo to a traveler. The cutter portion cuts the yarn tail.
in fine yarn tail cutting method disclosed in the above document, when the doffing is stopped, a ring rail 51 is stopped a; a part of a spindle base '3a that contacts a yarn tail cutting member 52. The spindle 53 is stopped with yarn Y wound about a portion lower than the contacting part. Next, as shown in Fig. SB, a doffing device 54 raises and removes a cop 55 from the spindle o3. Until the cop 55 is raised along the spindle 53 to a certain point, the yarn tail cutting member 52 is raised together with the cop 55. A traveler 56 is provided on a ring 51a. The yarn Y extending from the cop 55 to the traveler 56 is guided to the space between the yarn tail cutting member 52 and the spindJe base 53a. Thereafter, the yarn tail cutting member 52 separated from the cop 55 and the spindle base 53a hold (pinch) the yarn Y. The cutter portion of the yarn tail cutting member 52 cuts the yarn Y.
However, even if the yarn tail cutting method of the above document is applied, the ring rail 51 is held at a stopping oosition when the doffing device 54 raises and

removes the cop 55 from "he spindle 53. Normally, the cop 55 is raised and removed from the spindle 53 at a constant speed. Thus, the yarn Y extending from the cop 55 to a front:, roller (not shown) via the traveler 5 6 and a snail wire 57 is pulled, which moves the traveler 56. The amount of movement of the traveler 56 is not necessarily the same for all the spindles. When winding iS stopped for doffing or when the cop 55 is being raised and removed, the movement amount of the travelers 56 vary according to the behavior of the yamy Y and the travelers 56.
For example, while the cop 55 is raised from the position shown in Fig. 6A to the position shown in Fig. 6B, the Liavo'or 56 may move from the posizion shown in Fig. 6E to the position shown in Fig. 6F on rhe ring 51a. Specificarly, the traveler 56 rotates almost by 90° about the spindle 53. If the movement amount of the traveler 56 is great as in this case, the winding angle when the yarn Y is wound about the spindle 53 becomes small. Therefore/ when the yarn tail cutting member 52, which has separated from the cop 55, contacts aces the spindle base 53a, the yarn tail cutting member 52 and the spindle base 53a are likely to fail to hold (pincn) the yarn Y. As shown in Fig. 6C, the yarn Y extends from the cop 55 to the snail wire 57 directly /La the traveler 56. When rhe doffing device 54 raises and removes the cop 55 from the spindle 53 from the state of 6C, the yarn Y is cut at a position between the cop 5) and the snarl wire 57 dur i ng the raising and removing operation of the cop 55. That is, the state shown in Fig. 60 occurs.
SUMMARY
Accordingly, it is an objective of the present invention to provide a yarn tail cutting method that reduces

the length of a yarn tail remaining at a spindle base, and reduces broken threads.
According to one aspect of the invention, a yarn tail cutting method in a spinning machine is provided. The spinning machine includes: a ring rail; a traveler that runs along the ring rail; a spindle; and a yarn tail cutting member. The spindle includes a blade that extends upward from a spndle base. The yarn tail cutting member can be raised and lowered al<:ng the blade. yarn tail cutting mernbat includes: a boob i n receiving portion to which bobbin about is wound fitted and cutter located lower than portion. member spindle base are configured hold therebetween that extends from cop traveler.the method includes stopping during doffing ring rail at position corresponds part of contacts member. further in state where below contacting raising removing u sing device stopped. culting together with until raised predetermined point guiding space between base. holding has separated when removed using device.> Other aspects and advantages of the invention will become apoarent from the following description, taken in

conjunction with the accompanying drawings, illustrating by way of example the principles of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
The features of the present invention that are believed to be novel are set forth with particularity in the appended claims. The invention, together with objects and advantages thereof,lay best be understood by reference to the foil :>wing description of the presentntly preferred embodiments together with the accompanying drawings in which:
Figs. 1A and "IB arc side views, with a part cut away, illustrating a doffing operation of a doffing device acording to one ombodiment of the personal embodiment;
Figs. 1C and ID are schematic plan views corresponding to Figs. 1A and IB, respectively, showing the relationship between a cop and a t raveler;
Figs. 2A and 2B are side views, with a part cut away, illustrating the doffing operation of the doffing device, continued from Fig. IB;
Fig. 3 is a diagrammatic view showing a ring spinning frame;
Figs. 4A and 4B are schematic views showing the relationsnip between the ring spinning frame of Fig. 3 and the doffing device of Fig. 1A;
Fig. 5A is a side view, with a part cut away, showing the spindie of Fig. 1A;
Fig. 5B is an enlarged cross-sectional view of Fig. 5A, showing the state in which the yarn tail cutting member contacts a spindle base;
Figs. 6A to 6D are side views, 'with a part cut away, showing a doffing operation according to a prior art; and
Figs. 6E and 6F are schematic plan views corresponding to Figs. 6A and 6B, respectively, showing the relationship between a cop and a traveler.

DESCRIPTION OF THE PREFERRED EMBODIMENTS
One embodiment of the present invention will now be described with reference to Figs. 1A to 5B. The embodiment shows a yarn rail cutting method in a ring spinning frame.
Fig. 3 shows a spindle drive system for rotating spindles 1. The spindle drive system has a spindle motor 12, a dri-re pulley 13 driven by the spindle motor 12, a driven pulley 14, and a tangential belt 15 engaged with the drive pulley 13 and the driven pulley 14. The tangential belt 15 .is engaged w_i th the spindles 11.
Fief. 3 shows a lift motor 23 that lifts and lowers a ring rail. 17. A servomotor is used as the lift motor 23. A traveler T moves along a ring 17a of the ring rail 17. The drive shaft of the lift motor 23 is connected to a line shaft 16 .vith a gea r" mechan.i sm (not shown) . The 1 i.ne shaft 16 extends along the row of the spindles 11. A plurality of lift units 19 (only one is illustrated) is arranged along the line shaft 16 at predetermined intervals. The lift units 19 are configured to lift and lower the ring rails 17.
Specifically, each lift unit 19 has a worn 20 that is fitted to and rotates integrally witn the line shaft 16 and a nut body 22 that engages with the ^orm 20. The nut body 22 is engacred with a screw portion 21a. The screw portion 21a is termed in a lower portion of a poker pillar 21 that extends vcr t i cal.ly for supporting the ring rail 17. The structure of the lift unit 19 is basically the same as that disclosed in, for example, Japanese Laid-Open Patent Publication No. 7-300726. The line shaft 16, the lift unit 19, and the poker pillars 21 form a lifting drive system for lifting and lowering the ring rail 17. Figs. 1A and 2B show

a lappet 18 having a snail wire 18a. The lappet 18 can be raised and lowered in synchronization with the movement of the ring tail 17 .
Next, the spindle 11 and a yarn tail cutting member 28 incorporated in the spindle 11 will be described. The spindle 1 :. and the yarn tail cutting member 28 have the same structure as that disclosed in Patent Document 1.
As shown in Fig. 5A, a bolster 17 is fixed to a spindle rail 26. The spindle 11 is rotatab]y supported by the bolster 2 7 with a bearing. The spindle 11 includes a spindle saflt 25 and ?~ o" ade portion 2 4 that extends upward from the spindle shaft lb . The blade portion 24 has a blade 24a, to which a cylindrical bobbin E is attached, a spindle base 14b formed at a lower portion of the blade 24a, and a belt engaging portion formed at a lower portion of the spindle base 24b. The blade 24a, the spindle base 24b, and the be.lt engaging portion are formed integrally. The spindle base 24b has a larger diameter than the blade 24a. The blade 24a extends upward from the spindle base 24b.
As shown in Fig. 5B, the yarn tail cutting member 28 is attached to the blade 24a in such a manner as to be raised and lowered. The yarn tail cutting member 28 has a bobbin receiving portion 29 to which the bobbin B is fitted, and a cat v er per r.ion 30 located below the bobbin receiving portion 29. The cylindrical bobbin receiving portion 29 has an accommodation recess 2 9a that opens radially inwardly. The accommodation recess 29a accommodates a coil spring 31. A cylindrical collar 32, which functions as a stopper, is fixed to the blade 24a. When the yarn tail cutting member 28 contacts one spindle base 24b, the lower part, of the collar 32 corresponds to the upper end of the bobbin receiving portion 29. The outer diameter of the collar 32

is slightly less than the outer diameter of the accommoda ti on recess 2 9a . Therefore, when the yarn tail cutti.ng member 28 is raised and the ooii spring 31 is contracted, the accommodation recess 2 9a accommodates the collar 3?. The yarn :ail cutting member 28 slides along the collar 32. The outer diameter of the bobbin receiving portion 2 3 is reduced toward the upper end.
As snown in Fig. 5B, the lower end of the coil spring 31 or.tac-s the lower end of the accommodation recess 29a, and the upper ena of the coil spri ng 31 contacts the lower end of the collar 32. The coil spring 31 always urges the yarn tail cutting member 28 toward the spindle base 24b. The coil spring 31 functions as a limiting portion that prevents the yarn tail cutting member 28 from being raised above a predetermined height from Lho contact position with the spindle base 24b. The coil spring 31 and the collar 32 in the present embodiment set the upper limit of the movement of the cutter portion 30, that is, the limit of the upward movement of the cutter portion 30.
Referring to Fig. 5B', the cutter portion 30 is circular, and specifically, has a shape of a flat and circuiar truncated cone. The diameter of the circular edge of the cutter portion 30 is larger than the outer diameter of the lower end of the bobbin B in the present embodiment. An outer circumferential surface of the lower portion of the bobbin receiving portion 29 has an annular groove 33 for accommodating a rubber ring 34. The rubber ring 34 increases the force by which the bobbin receiving portion 2 9 and the bobbin B are engaged with each other. Part of the rubber ring 34 prot r Lidos from the groove 33 and contacts the ;nner circumferential surface of the bobbin B.
Fiat. 4A and 4B show a known doffing device 35 (bobbin

replacement: device) that simultaneously performs doffing for all the soindles used in a ring spinning frame. The doffing device 35 includes a doffing bar 36 having bobbin holders 36a. A transport device 37 located below the spindle rail 2 6 has a peg 37a for supporting a empty bobbin B. The doffing device 35 replaces an empty bobbin B or. the peg 37a with a coo 38 on the spindle 11. In the doffing, the bobbin holder 36* raises and removes the empty bobbin B from the peg 37a, moves the empty bobbin B along arrows shewn in Fig. 4A, and pats the empty bobbin. B on a middle peg 39. Next, the bobbin holder 36a is moved to a position above the cop 38 on the spindle 11. The bobbin ho 1der 36a is moved along arrows shown in Fig. 4 B to hold the cop 38, raises and removes the cop 38 from the spindle 11, and puts the cop 38 onto the peg 37a. Next, the bobbin holder 36a is moved along arrows shown in Fig. 4A, and puts the empty bobbin B on the middle peg 39 onto the spindle 11. Next, the. bobbin holder 3ba is moved along arrows shown in Fig. 4B, and is returned co a standby position above the peg 37a.
An operation of this embodiment will now be described.
As shown in Fig. tA, when the bobbin B is attached to the spindle 11 so as to be integrally rotatable, the lower portion of the bobbin B is engaged with the bobbin receiving portion 29. When the spindle motor 12 rotates the spindle 11 through the tangential belt 15, the bobbin B rotates integrally with the spindle 11.
When, as a result of the spinning, a full bobbin state occurs, that is, when yarn Y is fully wound about the bobbin 3, a predetermined procedure for stopping the spindle 11 is executed. That is, through the same operation as the prior art, the ring rail 17 is rapidly lowered, so that inclined wine:no 3 8a (shown in Fig. 1A) is applied to the cop 38 that is fully wound about the bobbin B. Thereafter, the ring

rail 17 is stopped at a position in the vicinity of a position at which the spindle base 24b contacts the yarn tail cutting member 23. The traveler T on the ring rail 17 is located slightly lower than the position at which the spindle base 24b contacts the yarn rail cutting member 28, That is, "he traveler T is located slightly lower than the position at which the spindle base 24b contacts the lower surface of the cutter portion 30. bake is applied to the spindle 1 '. for stopping the spindle 11 at a position slightly tower than a position at which the spindle base 24b contacts :he yarn tail cutting member 28, such that less than one coll, for example, half roll of yarn is wound about the spindle 11. The lappet 18 is positioned at a retreat position where it does not interfere with the doffing. As a result, t'ne state shown in Fig. 1A occurs.
In other words, in the doffing, the ring rail 17 is stopped at a position that corresponds to a position at which the spindle base 24b contacts the yarn tail cutting member 28. In this specification, "the position that corresponds to a part oi the spindle base 24b that contacts the yarn tail cutting member 28" refers to a position of the rinq rail 1.7 where the yarn Y extending from the traveler T to the cop 38 can be entriduced to a space between the cutter portion 30 and the L hc car> 38 can be antr.oduced to aspace between the cutter portion 30 and the spindle base 2 4b when the yarn tail cutting member 2B contacts the spindle base 24b.
Then, the doffing device 35 is activated. The bobbin holcer 3 6a raises and removes the cop 38 fully wound about the bobbi n R from the spindle 11. The lift motor 23 raises the ring rail 17. The lift motor 23 raises the ring rail 17 at the same speed of the raising/removing speed of the cop 38. Until the cop 38 is raised along the spindle 11 to a certa.x point, the yarn tail cutting member 28 is raised together with the cop 38. As shown in Fig. IB, the yarn Y

extending from the cop 38 to the traveler T is guided to the space between the yarn tail cutting member 28 and the spindle base 24b.
As described above, the ring rail 17 is raised simultaneously with the cop 38 when Lhe cop 38 is raised and removed from, the spindle 11. Thus, 'while the cop 38 is raised from the position shown in Fig. 1A to the position shown in '7ig. IB, the .increase in the tension of the yarn Y extending from the cop i8 to the traveler T is limited. As a result, even if the cop 38 is raised as shown in Figs. 1C ana ID, the position of the traveler T relative to the ring 17a is no*; changed. .figs. 1C and ID show states that are different from the prior art traveler 5 6 shown in Figs. 6E ano 6F. Thus, in this embodiment, the angle of the inclination of winding of the yarn Y about the spindle 11 is not reduced. As a result, from when the yarn tail cutting member 2 8 separates from the cop 33 to when the yarn tail cutting member 28 reaches a position for contacting the spindle base 24b, the yarn "ail cutting member 2 8 hardly fails uo hold the yarn Y.
The r.ovability of the traveler T is influenced by the spinning conditions, such as the size and the number of twist. If the spun yarn is thin, the weight of the traveler T is reduced, and the traveler T .is easy to move. Thus, compared to a case in which yarn of 4 0 counts is spun, the traveler I is easier to move when yarn of 8 0 counts, which .is thinner than the yarn of 40 counts, is spun. "When tension is applied re a yarn Y having snarl, the yarn Y is likely to separate from the traveler T or to move significantly. Therefore, according to the spinning conditions, the permissible value of the tension of the yarn Y when Lhe cop 38 is rai sed and removed from the spindle 11 varies. In the present embodiment, when the cop 38 is

raised and removed from the spindle 11, the ring rail 17 and the cop 38 are simultaneously raised at the same speed. Therefore, the increase in the tens i on of the yarn Y is minimized,
The upper limit of the ring rail 1.7 (limit of upper movement) is set such that the traveler T is lower than the upper surface of the cutter portion 30 when the cutter portion 3') is at the highest position. In the present embodiment, the upper surface of the cutler portion 30 in a state where the yarn rail cutting member 28 contacts the spindle base 24b is sot as a reference, and the upper limit of the ring rail 17 is set. such that the traveler T is located w.i.hin 10 rnm above the reference. Specifically, the upper limit of the ring rail 17 is set such that the traveler T is located 5 mm above the reference. The position of the traveler 7 that corresponds to the upper limit of the ring rai L 17 corresponds to the position of half the maximum opening degree of the yarn tail cutting member 28. "The maximum opening degree of the yarn tail cutting member 28" refers to the maximum distance between the cutte:: portion 30 and the spindle base 24b.
When the yarn tail cutting member 2 8 reaches a predetermined height with the cop 38, the urging force of the coil spring 31 causes the yarn tail cutting member 28 to separate from the cop 38. Then, the yarn tail cutting member; 23 is lowered and contacts the spindle base 24b. The yarn tail cutting member 28 and the spindle base 24b hold (pinch) the yarn Y extending from the cop 38 to the traveler T. The cop 38 is being continuously raised. Thus, the cutter portion 30 is pressed against the tense yarn Y, and, as a result, cuts the yarn Y. The state shown in Fig. 2A occurs. The yarn tail cutting member 28 and the spindle base 24b can hold (pinch) the yarn Y after the yarn Y is

cut. The yarn Y extends from the yarn tail cutting member 28 and the spindle base 24b to the front roller 40 shown in Fig. 3 via the traveler T and the snail wire 18a.
After the cop 38 is doffed, the state shown in Fig. 2B occurs. An empty bobbin B is placed on the spindle 11. The lappet 18 is positioned at a winding position. Thereafter, the machine is restarted. Until the next doffing, the yarn tail cutting member 28 and the spindle base 24b continue to hold (pi.n<:h the end of yarn y extending from traveler rn. tail hel d nc.hed by ta.i .1 cutring member and spindle base is connected to a cop in rhe next doffing separated .> The present embodiment has the following advantages.
(1) I.1 he yarn tail cutting member 28 with the cutter portion 3) is lowered after being raised with the cop 38 during doffing. As a result, the yarn tail cutting member 23 and the spindle base 24b hold (pinch) the yarn Y extending from the cop 38 to the traveler T. The cutter portion 3") cuts the yarn Y. Therefore, the present embodiment: is different from the prior art that holds a yarn tail by winding the yarn La LI about a spindle 53. That is, according ro the present embodiment, the yarn tail does not need to be wound about: the spindle V. several times. Further, in the present embodiment, no special yarn tail wind1 no oortion is formed. Thus, it is possible to reduce the amount of thread remaining on the spindle base 24b (yarn tail) b y a s L mp 1 e s L r. \ i c 11 I r e .
(2} When the doffing device 3 5 raises and removes the cop 38 from the spindle 11, the ring rail 17 is also raised. Thus, when the cop 33 is raised and removed from the spindle 11, the yarn Y that is connected to the front roller 40 from

the cop 38 via the traveler T and the snail wire 18a is prevented from being pulled. As a result, the movement of the traveler T is limited. Therefore, when the yarn tail cutting member 28 separates from the cop 38, which is being raised, and returns to a position to contact the spindle base 24b, the yarn tail cutting member 28 is less likely to fail to hold the yarn Y extending from the cop 38 to the traveler. Further, compared to the; prior art, yarn tail cutting ir; reliably executed without fail.
(3) When the cop 38 is raised and removed from the
spindle I., the tension of the yarn Y extending from the cop
38 to the snail wire 18a via the traveler T is increased.
In the present embodiment, the raising speed of the ring rail 17 is the same as the raising/removing speed of the cop 36. Thus, the increase in the tension of the yarn Y is minimized . Thi s further prevents the yarn tail cutting member 28 from failing to hold the yarn Y.
(4) The upper limit of the ring rail 17 is set such
that the traveler T is lower than the upper surface of the
cutter portion 30 when the cutter portion 30 is at the
highest position. If the yarn tail cutting member 28
separates from the cop 38 in a state where the traveler T is
located at a position higher than the upper surface of the
cutter portion 30, in other words, in a state where the
traveler V is displaced from a space (opening) between the
lower surface of the yarn tail cutting member 28 and the
spindle base 24b, the possibility that the yarn Y fails to
bo held is increased. However/ in the present embodiment,
the yarn tail cutting xember 28 sepa rates from the cop 38 in
a state wnere the traveler T exists oetween the lower
surface of the yarn tail cutting mernoer 28 and the spindle
base 24b. This reduces the possibility that the yarn tail
cutting member 28 fails to hold the yarn Y.

(5) The spindle 11 has the coil spring 31, which functions as a limiting member for limiting the upward movement of" the yarn tail cutting member 28. The coil spring 31 sets the upper limit of the cutter portion 30. Therefore, the upper limit of the culler portion 30 is easily set, and as a result, the upper limit of the ring rail 17 t easily set.
(6) "the upper surface of the cutter portion 30 in a state where the yarn call cutting member 28 contacts the spindle base 24b is used as a reference. The upper limit of the ring rail 17 is set such that the traveler T is located 10 mm above the reference. If the raised position of the traveler 7 is too far from a part of the spindle base 24b that contacts the yarn tail cutting member 28, the yarn tail cutting member 28 is likely to fail to hold the yarn Y. The present embodiment, however, reduces the possibility of such failure.
(7) The upper limit of the ring rail 17 is set such that the traveler T corresponds to the position of half the maximum opening degree of the yarn tail cutting member 28. Compared to a case where the upper limit of the ring rail 17 is set such that the traveler T corresponds to a position close to the upper limit of the maximum opening degree of the yarn tail cutting member 28, the yarn Y is less likely to fail to be held in che present embodiment.
(8) The coil spring 31 always urges the yarn tail
cuttincf member 28 toward the spindle base 24b. Therefore,
the yarn tail cutting member 28 contacting the spindle base
24b reliably holds the yarn Y extending to the traveler T.
The present invention is not limited to the above

embodiments but may be modified as follows.
The speed at which the ring rail 17 is raised when the doffing device 35 raises and removes the cop 38 from the spindle 11 does not need to be the same as the raising/removing speed of the cop 38. That is, the raising speed of "he ring rail 17 may be slower or faster than the raising/removing speed of the cop 38. However, it is preferable that the raising speed of the ring rail 17 be the same as the raising/removing speed o;" the cop 38, since this setting of. the speeds minimizes the increase in the tension of the yarn Y and easily prevents the yarn tail cutting member 28 from failing to hold the yarn Y.
The upper limit of the ring ra.i I 17 does not need to be set such "that, when the doffing device 35 raises and removes the cop 3 3 from the spindle 11, the traveler T corresponds to a position of half the maximum opening degree of the yarn tail cutting member 28. For example, the upper limit of the ring rail 17 may be set such that the traveler T is higher than the oosition of half the maximum opening degree of the yarn tail cutting member 28. Contrastingly, the upper limit of the ring rail 17 may be set such that the traveler T is lower than the position of half the maximum opening degree of the yarn tail cutting member 28.
However, it is preferable that the upper limit of the ring rail 17 be set such that the traveler T is lower than the upper surface of the cutter portion 30 when the cutter portion 30 is at the highest position. This is because, if the yarn tail cutting member 28 separates from the cop 38 in a state where the traveler I1 is located at a position higher that- the upper surface of the cutter portion 30, in other woco.s, ir. a state whe re the traveler T is displaced from an opening between the yarn tail cutting member 2 8 and the

spindle base 24b, it is more likely that the yarn tail cutting member 28 fails to hold the yarn Y. However, depending on the size and the number of twist, there are cases where the yarn tail cutting member 28 is prevented from failing to hold the yarn Y even if the traveler T is displaced from the opening between the yarn tail cutting member 28 and the spindle base 24b.
The lpper surface of the cutter portion 30 in a state where the yarn tail cutting member 2o contacts the spindle base 24b may be set as a reference, and the upper limit of the ring call 17 when r he doffing device 35 raises and removes the cop 38 fr^m the spindle '..1 may be set such that the traveler T is located at a position 10 mm above or higher than the reference. However, it is preferable that the upper limit of the ring rail 17 be set such that the traveler T is located at a position 10 mm or less above the reference. This is because, if the raised position of the traveler T is too far from a part of the spindle base 24b that contacts the yarn tail cutting member 28, the yarn tail cutting member 28 is more likely to fail to hold the yarn Y. If the raised position of the traveler T is within 10 mm above the reference, the failure of holding yarn is unlikely to occur even if the spinning conditions are changed.
When the doffing device 35 raises and removes the cop 38 from tae spindle, the ring rail 17 does not need to be raised at the same as when the cop 38 starts being raised from the spindle 11. For example, the ring rail 17 may star being raised after or- before the cop 38 starts being raised from the spindle 11. However, it is preferable that the ring rail 17 start being raised simultaneously as the cop 38 starts being raised and removed from the spindle 11, since the increase ir the tension o ■". the yarn Y Is suppressed.

In the illustrated embodiment, the coil spring 31 located between the collar 32 and the yarn tail cutting merber 28 functions as a limiting portion for limiting the upward movement of the yarn tail cutting member 28. However, the limiting member does not need to be the coil spring 31. For example, the coil spring 31 and the collar 32 may be omitted, and a stopper may be fixed to a predetermined part of the blade 24a. The stopper contacts the bobbin receiving portion 29 to limit the upward movement of the ya-m\n Lail cuLling member 28. When being raised together with the cop 38, the yarn tail cutting member 28 contacts the stopper and thus separates from the cop 38.
The cutter portion 30 does not need to be circular, but may be sawtooth shaped. Alternatively, an annular blade may be formed separately from the main body of the cutter portion, and the main body may have waging portions for fi x inq the blade to the ma in body.
The spindle 11 does not need to be driven with a belt drive systern. For example, motors each corresponding to one spindle may be provided. That is, the spindles 11 may be driven by a single spindle drive method. Further, the spindles 11 do not need to be driven with the single tangential belt 15. It may be configured that each set of four consecutive spindles 11 may be engaged with and driven by a single belt.
The system for driving the ring rail 17 may be independent from the system for driving the spindles 11 or from the system for driving the draft machine. The system for driving the ring .-rail 17 may be any type as long as the system is capable for: lifting and lowering the ring rail 17.

The rubber ring 34 is used as a member for increasing the force by which the bobbin B is engaged with the bobbin receiving portion 29. However, a lea f* spring may be employed ror this purpose.



CLAIMS:
1. A yarn tail cutting method in a spinning machine, wherein the spinning machine includes: a ring rail (17); a traveler (T) that runs along the ring rail (17) ; a spindle (11); and a yarn tail cutting member (28), wherein the spindle (11) includes a blade (24a) that extends upward from a spindle base (24b), wherein the yarn rail cutting member (28) can be raised and lowered along the blade (24a), wherein tie yarn tail cutting member (28) includes: a bobbin receiving portion (29) to which a bobbin (B) about which yarn (Y) i.s wound is fhitted; and a cutter portion (30) located lower than the bobbin receiving portion (29), and wherein t'ne yarn tail cutting member (28) and the spindle base (24b: are configured to hold therebetween the yarn (Y) that exteids from a cop (38) to the traveler (T), the method comprising:
stopping, during doffing, the ring rail (17) at a position that corresponds to a part of the spindle base (24b) that contacts the yarn tail cutting member (28);
stopping the spindle (11) in a state where the yarn (Y) is wound at a position below the contacting part;
raising and removing the cop (38) from the spindle (11) using a doffing device (35), in a state where the spindle (11) is stopped;
raising the yarn tail cutting member (28) together with the cop (38) until the cop 38 is raised to a predetermined point;
guiding the yarn (Y) to a space between the yarn tail cutting member (28) and the spindle base (24b);
holcing the yarn (Y) between the yarn tail cutting member (23), which has separated from the cop (38), and the spindle base (24b); and
cutting the yarn (Y) with the cutter portion (30),
:;he method beinc characterized by raising the ring rail

(17) when the cop (38) is raised arid removed from the spindle (."1 1} using the doffing device (35).
2. The yarn tail cutting method according to claim 1,
characterized in that the raising speed of the ring
rail (17) is set to be the same as the raising/removing
speed of the cop (38).
3. Tne yarn tail cutting method according to claim 1 or
o
characterized in that the upper limit of the movement
of the ring rail (17) is set such that the traveler (T) is lower: thai": an upper surface of the cutter portion (30) when the cutter portion (30) is at the highest position.
4. The yarn tail cutting method according to claim 3,
characterized in that the spindle (11) is provided with
a limiting member (31) for limiting the upward movement of the yarn tail cutting member (28), the limiting member (31) limiting the upper limit of the movement of the cutter portion (30).
5. The yarn tai1 cutting method according to any one of
claims 1 to 3,
characterized in that an upper surface of the cutter
portion (30) in a state where the yarn tail cutting member (26) contacts the spindle base (24b) is set as a reference, and the upper limit cf the movement of the ring rail (17) is determined such that the traveler (T) is located within 10 mm above the reference.
5. The yarn ta.i 1 cutting method according to any one of claims 1 to 4,
characterized in that raising of the ring rail (17) is started al the same time when the cop (38) starts being

raised and removed.


Documents:

0801-che-2007-abstract.pdf

0801-che-2007-claims.pdf

0801-che-2007-correspondnece-others.pdf

0801-che-2007-description(complete).pdf

0801-che-2007-drawings.pdf

0801-che-2007-form 1.pdf

0801-che-2007-form 18.pdf

0801-che-2007-form 26.pdf

0801-che-2007-form 3.pdf

0801-che-2007-form 5.pdf

801-CHE-2007 AMANDED CLAIMS 24-05-2010.pdf

801-CHE-2007 AMANDED PAGES OF SPECIFICATION 24-05-2010.pdf

801-CHE-2007 CORRESPONDENCE OTHERS 25-10-2010.pdf

801-che-2007 form-3 24-05-2010.pdf

801-CHE-2007 CORRESPONDENCE OTHERS 24-05-2010.pdf

801-CHE-2007 POWER OF ATTORNEY 24-05-2010.pdf

abs-801-che-2007.jpg


Patent Number 244900
Indian Patent Application Number 801/CHE/2007
PG Journal Number 53/2010
Publication Date 31-Dec-2010
Grant Date 23-Dec-2010
Date of Filing 16-Apr-2007
Name of Patentee KABUSHIKI KAISHA TOYOTA JIDOSHOKKI
Applicant Address 2-1, TOYODA-CHO, KARIYA -SHI, AICHI-KEN, JAPAN
Inventors:
# Inventor's Name Inventor's Address
1 YAKUSHI, MAKATO C/O KABUSHIKI KAISHA TOYOTA JIDOSHOKKI 2-1, TOYODA-CHO, KARIYA -SHI, AICHI-KEN, JAPAN
2 AMANO, HISAO C/O KABUSHIKI KAISHA TOYOTA JIDOSHOKKI 2-1, TOYODA-CHO, KARIYA -SHI, AICHI-KEN, JAPAN
PCT International Classification Number D01H 9/16
PCT International Application Number N/A
PCT International Filing date
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 2006-113505 2006-04-17 Japan