SPINNING RING

Abstract: A spinning ring (10) serves to take up a thread (T), introduced from an element bobbin (70), round a bobbin (82), and comprises a stationary cylinder (20), a revolving cylinder (30) and a traveller (50). The stationary cylinder (20) is mounted to a ring rail (74). The revolving cylinder (30) is provided concentrically of and inside the stationary cylinder (20) to be rotatable about a central axis of the stationary cylinder (20). The bobbin (82) is provided concentrically of and inside the revolving cylinder (30) to be rotatable about a central axis of the revolving cylinder (30). The traveller (50) is provided to be rotatable circumferentially of the revolving cylinder (30) relative thereto to guide a thread (T), introduced from the element bobbin (70), to the bobbin (82). When the bobbin (82) performs steady-state revolution, it is set such that a speed of the traveller (50) relative to the revolving cylinder (30) is substantially zero and the traveller (50) and the revolving cylinder (30) revolve relative to the stationary cylinder (20) in a substantially integral manner.

Description: This invention relates to spinning rings for winding yarns fed from yarn feeders on bobbins. Among prior art spinning rings of the pertaining type is one which comprises a stationary ring, a rotary ring and a traveler. The stationary ring is secured to a base member. The rotary ring is disposed inside and concentrically with the stationary ring for rotation about the central axis thereof. The bobbin is disposed inside and concentrically with the rotary ring for rotation about the central axis thereof. The traveler is provided on the rotary ring for revolution in the circumferential direction of the rotary ring to guide the yarn fed from the yarn feeder to the bobbin. With the rotation of the bobbin, the traveler undergoes revolution along the edge of outer periphery of the rotary ring in the circumferential direction thereof, so that the yarn fed from the yarn feeder is taken up on the bobbin while being twisted. When the traveler is caused to undergo revolution, the rotary ring is caused to be rotated. The yarn (raw yarn) fed from the yarn feeder is thus spun and taken up on the bobbin. The higher the rotation speed of the bobbin, the better the spinning efficiency. The rotation of the bobbin and the revolution of the traveler correspond to each other, and also the revolution of the traveler and the rotation of the rotary ring are related to each other. EP 0 401 008 A2 discloses a spinning ring according to the preambles of claim 1. US 4 238 920 discloses a spinning ring according to the preamble of claim 1 without a slide ring. It is an object of the invention to improve the spinning efficiency by improving the revolution characteritics of the traveler and of the rotary ring. This object is achieved by a spinning ring according to claim 1. Further developments of the invention are given in the dependent claims. When the bobbin starts to be rotated (i.e., accelerated), the traveler is caused to undergo revolution relative to the rotary ring, so that the rotary ring is caused to start rotation gradually relative to the rotary ring. When the bobbin reaches the normal operating speed (but not always right after the normal operating speed is reached), the rotary ring is rotated at a speed corresponding to the rotational speed of the bobbin to make substantially zero the speed of revolution of the traveler relative to the rotary ring. Consequently, the traveler and the rotary ring are rotated substantially in unison with each other relative to the stationary ring. In this state, the traveler no longer receives substantial frictional force due to its rotation relative to the rotary ring. The burden (i.e., degree of damage) of the traveler is reduced, so that its life can be extended. In addition, the speed of rotation of the bobbin can be increased to obtain improved production efficiency. A braking force is applied to the rotary ring, the rotation of which is related to the revolution of the traveler. Consequently, a braking force is applied with respect to the revolution of the traveler. When the bobbin is rotated at high speed so that the yarn undergoes high speed revolution in unison with the rotary ring and the traveler, the yarn is expanded side-wise by a great centrifugal force. If the phenomenon of side-wise expansion of ballooning is pronounced, the yarn may be in highly forced contact with an adjacent member or the like to be broken (ballooning collapse phenomenon). Owing to the braking force applied to the rotary ring and the traveler, the yarn is always pulled by a predetermined pulling force. The ballooning collapse is thus suppressed to prevent the yarn from being in contact with an adjacent member or the like and being broken. In addition, when the rotary ring and the traveler are stopped after delay when the bobbin is stopped (over-run rotation), the yarn is disturbed in the neighborhood of the traveler (snarl phenomenon). Such a snarl phenomenon is prevented by the braking force acting on the rotary ring and the traveler. In the spinning ring in a second aspect of the invention, the brake section is a non-flat air brake section for applying to the rotary ring a braking force which is based on a frictional force produced between the brake section and the air around the rotary ring. The frictional force between the air brake section and the neighboring air is increased with increasing rotational speed of the rotary ring, and the braking force is applied to the rotary ring in correspondence to the rotational speed of the rotary ring. It is thus possible to more effectively obtain the effect in the second aspect of the invention. In the spinning ring in the second aspect of the invention, the air brake section comprises a plurality of blades extending in the radial direction of the rotary ring. In the spinning ring in a third aspect of the invention, the brake section comprises a plurality of brake elements capable of advancement and retreat in the radial direction of the rotary ring, the brake elements being advanced by centrifugal forces generated with the rotation of the rotary ring, the advanced brake elements being brought into contact with the stationary ring. when centrifugal forces are applied to the brake elements in correspondence to the rotational speed of the rotary ring, frictional forces are generated between the blade elements and the stationary ring when the brake elements are advanced and brought into contact with the stationary ring. A braking force is thus applied to the rotary ring in correspondence to the rotational speed of the rotary ring. Thus, it is possible to more effectively obtain the effect of the invention. The slide ring permits smoother rotation of the rotary ring relative to the stationary ring, and thus enables high speed rotation of the rotary ring. The slide ring may have a single cut section. With the rotation of the rotary ring in unison with the traveler, the slide ring receives impact force in its radial direction. However, since the slide ring has a cut section, it can be elastically deformed to increase or reduce the clearance of the cut section. The slide ring thus can be elastically expanded or contracted just like a spring, so that it can absorb the impact force from the rotary ring with its elastic deformation to reduce the degree of re-transfer of the impact force from the rotary ring back to the same. Impact force thus is not transferred back to the rotary ring so much, and smooth high speed rotation of the rotary ring can be ensured. The slide ring may be divided into a plurality of ring portions. As noted above, with the rotation of the rotary ring in unison with the traveler, the slide ring receives impact force in its radial direction. However, since the slide ring is divided into a plurality of ring portions, these ring portions can readily be moved finely in the radial direction when impact force is applied thereto in the radial direction with the rotation of the rotary ring. Thus, they can readily absorb the impact force with their fine movement, thus ensuring smooth rotation of the rotary ring. The slide ring may have a portion thinner than other remaining portions. The thin portion can more readily undergo elastic deformation than other portions, so that it can absorb the impact force developed by the rotation of the rotary ring by a greater degree. The slide ring may comprise a main ring made of an elastic material and having a cut section and a reinforcement ring without any cut section and fitted on the main ring. The slide ring is rotated with the rotation of the rotary ring. If the slide ring comprises the sole main ring with a cut section, it may be expanded by centrifugal force generated by its rotation to be in forced contact with the stationary ring. As a result, the frictional force (i.e., sliding resistance) between the stationary ring and the slide ring is increased, thus possibly preventing smooth rotation of the rotary ring. Owing to the reinforcement ring, the main ring is not expanded beyond a predetermined diameter, that is, the slide ring itself is not expanded beyond a predetermined diameter. Thus, it is possible to prevent forced contact of the slide ring with the stationary ring and ensure smooth rotation of the rotary ring. The main ring and the reinforcement ring may have different vibration attenuation characteristics. With the different vibration attenuation characteristics of the main ring and the reinforcement ring, vibrations of the rotary ring developed by the rotation thereof can be more effectively attenuated. The "plurality" in claim 9 is typically "two". With the revolution of the traveler generating tension in the yarn, the rotary ring tends to undergo fine precession. According to claim 9, such precession is prevented by the plurality of slide rings provided at a predetermined interval in the central axial direction of the stationary ring and the rotary ring, and the rotary ring is rotated accurately about its central axis. Since the precession of the rotary ring is prevented, the traveler undergoes uniform revolution, that is, smooth high speed revolution of the traveler is ensured. In addition, without precession of the rotary ring, smooth rotation of the rotary ring is not disturbed by increasing friction (i.e., rotational resistance) between the rotary ring and the stationary ring, and smooth high speed rotation of the rotary ring can be ensured. The slide rings can be made of elastic synthetic resin, elastomer or metal. In a preferred embodiment, the stationary ring is mounted in the base member such that it is fitted in a mounting hole in the base member, and at least a portion of the stationary ring that is in contact with the base member being made of a synthetic resin. It will be noted that the whole stationary ring may be made of a synthetic resin. Since not only the traveler undergoes revolution but also the rotary ring is rotated relative to the stationary ring, high impact force is applied to the stationary ring. However, at least a portion of the stationary ring that is in contact with the base member is made of a synthetic resin. Thus, compared to the case of a stationary ring made of a metal, the impact force is alleviated between the stationary ring and the base member. Consequently, the degree in which the impact force is retransferred from the base member to the rotary ring and other parts can be reduced to permit smooth take-up of the yarn on the bobbin. In addition, the revolution of the traveler generating tension in the yarn, the rotary ring undergoes fine precession, and this motion causes fine precession (i.e., fine vibrations) of the stationary ring as well. Therefore, if the stationary ring is made of a metal, its portion in contact with the base member may separate coating of the base member (which is usually made of a metal and is provided with a coating on its surface) due to its fine vibrations. In such a case, the portion of the base member with the coating separated therefrom may be rusted to stain the yarn with the rust. According to the embodiment, this does not occur because at least a portion of the stationary ring that is in contact with the base member is made of a synthetic resin. Rusting of the base member thus is eliminated. The rotary ring may be a one-piece molding. This permits increased accuracy of the rotary ring. Various other features of the invention are conceivable, which are combinations of the above features. It follows a description of preferred embodiments referring to the drawings, of which: FIG. 1 is a view showing a spinning apparatus using spinning rings 10 (110, 210, 310, 410) as an embodiment of the invention. FIGS. 2 to 8 are views for describing the spinning ring 10 according to a first embodiment of the invention, in which FIG. 2 is an exploded perspective view showing spinning rings 10 and a ring rail 74 shown in FIG. 1; FIG. 3 is a sectional view showing the spinning ring 10 and its neighboring parts; FIG. 4 is a fragmentary sectional view, to an enlarged scale, showing the spinning ring 10; FIG. 5 is a perspective view of a brake ring 46 in FIG. 4, shown inverted upside down; FIG. 6 is a perspective view showing a slide ring 40 in the spinning ring 10 shown in FIG. 4; FIG. 7 is a view showing the spinning rings 10 and their neighboring parts in the apparatus shown in FIG. 1 in an operating state; and FIG. 8 is a view showing an advantage of the spinning ring 10 in comparison to FIG. 4. FIGS. 9 to 15 are views for describing modifications of the slide ring 40 in the spinning ring 10 of the first embodiment, in which FIG. 9 is a fragmentary perspective view showing a slide ring 40A; FIG. 10 is a fragmentary perspective view showing a slide ring 40B; FIG. 11 is a fragmentary perspective view showing a slide ring 40C; FIG. 12 is a fragmentary sectional view showing a slide ring 40D; and FIG. 13 is a fragmentary perspective view showing a slide ring 40E. FIG. 14 is a perspective view showing a brake ring 46A, shown inverted upside down, as a modification of the brake ring 46. FIG. 15 is a fragmentary perspective view showing a brake ring 48B, shown inverted upside down, as a different modification of the brake ring 46. FIGS. 16 to 18 are views for describing the spinning ring 110 according to a second embodiment of the invention, in which FIG. 16 is a fragmentary sectional view (corresponding to FIG. 4) showing the spinning ring 110; FIG. 17 is a perspective view showing a slide ring 140 in the spinning ring 110 shown in FIG. 16; FIG. 18 is a perspective view showing a brake ring 146 in the spinning ring 110 shown in FIG. 16; and FIG. 19 is a perspective view showing a brake element 148 in the brake ring 146 shown in FIG. 18. FIGS. 20 to 28 are views for describing a modification of the spinning ring 110 of the second embodiment, in which FIG. 20 is a fragmentary sectional view showing part of a rotary ring 130A as a modification of a rotary ring 130 and its neighboring parts; FIG. 21 is a perspective view showing a brake element 148A in the rotary ring 130A shown in FIG. 20; FIG. 22 is a fragmentary perspective view showing a brake ring 146B as a modification of the brake ring 146; FIG. 23 is a perspective view showing a brake element 148B in the brake ring 146B shown in FIG. 22; FIG. 24 is a fragmentary perspective view showing a brake ring 146C as a different modification of the brake ring 146; FIG. 25 is a perspective view showing a brake element 148C in the brake ring 146C shown in FIG. 24; FIG. 26 is a fragmentary sectional view (corresponding to FIG. 16) showing a spinning ring 210 as a modification of the spinning ring 110; FIG. 27 is a perspective view showing a slide ring 240 in the spinning ring 210 shown in FIG. 26; and FIG. 28 is an exploded perspective view showing the slide ring 240 shown in FIG. 27. FIG. 29 is a fragmentary sectional view (corresponding to FIGS. 4 and 16) for describing a spinning ring 310 according to a third embodiment of the invention. FIG. 30 is a fragmentary sectional view for describing the spinning ring 410 as a modification of the spinning ring 310 of the third embodiment. First Embodiment A spinning apparatus employing spinning rings 10 (110, 210, 310, 410) as an embodiment of the invention will first be described with reference to FIG. 1 and other figures. Above the spinning apparatus (FIG. 1), a number of raw yarn bobbins (or yarn feeders) 70 are provided in a row extending in a direction at right angles to the plane of paper. Drafting devices 72 are disposed on the opposite sides of a substantially central part of the apparatus in the height direction thereof. On the opposite sides of a lower part of the apparatus, ring rails (or base members) 74 (see FIG. 2) extend in a direction at right angles of the plane of paper. The ring rails 74 are vertically movable by a drive force of a motor (not shown) as they are guided by vertically extending guide rods 78. As shown in FIGS. 2 and 3, each ring rail (or base member) 74 has a number of mounting holes 75 arranged in a row extending in a direction at right angles to the plane of paper of FIG. 1. The spinning rings 10 (110, 210, 310, 410) are each fittedly mounted in each of the mounting holes 75. The ring rails 74 are made of iron and have a coating provided on their surface. Above the ring rails 74, guide members 76 are disposed such that they each face each spinning ring 10. Each guide member 76 has through holes 77 formed therein. A separator (or partitioning member) 95 is provided between adjacent spinning rings 10 (see FIG. 7). As shown in FIGS. 1, 3 and 4, a spindle 80 which is rotatable by a motor (not shown), extends along the axis of each spinning ring 10. A take-up bobbin (or spun yarn bobbin) 82 (not shown in FIG. 1) is fitted on the spindle 80 such that it is not rotatable relative thereto. Yarn T (i.e., raw yarn T1) fed from each raw yarn bobbin 70 is led through each drafting device 72, the corresponding through hole 77 in each guide member 76 and a traveler 50 of each spinning ring 10 to each bobbin 82. Yarn T (i.e., spun yarn T2) is taken up on the bobbin 82 with the rotation of the spindle 80 and the bobbin 82 while the associated ring rail 74 is moved vertically. The spinning ring 10 will now be described. As shown in FIGS. 2 to 4, the spinning ring 10 comprises a stationary ring 20, a rotary ring 30 and the traveler 50. The stationary ring 20 is made of a synthetic resin. As shown in FIG. 4, its outer peripheral part has a cylindrical mounting portion 22 and a ring-like mounting surface 24. The mounting portion 22 has a stop ring mounting groove 26 formed in its lower portion. The inner peripheral part of the stationary ring 20 has a slide ring outer portion receiving recess 21 formed in its upper portion. The rotary ring 30 is disposed inside and concentrically with the stationary ring 20 for rotation about the central axis thereof. The rotary ring 30 has a ring-like flange 32 formed at its top. The outer peripheral part of the rotary ring 30 has a slide ring inner portion receiving recess 31. A slide ring 40 is provided between the stationary ring 20 (i.e., the slide ring outer portion receiving recess 21) and the rotary ring 30 (i.e., the slide ring inner portion receiving recess 31). The slide ring 40 is made of an engineering plastic material, elastomer or metal which is elastic, heat-resistant and wear-resistant and has a very small coefficient of friction. As shown in FIG. 6, the slide ring 40 has a rectangular sectional profile, and it has a cut section 40a. The slide ring 40 offers low frictional resistance to and slidable relative to both the stationary ring 20 and the rotary ring 30. The rotary ring 30 is assembled with the stationary ring 20 via the slide ring 40, and it is not in direct contact with the stationary ring 20. The rotary ring 30 is thus smoothly rotatable relative to the stationary ring 20. Turning to FIG. 4, a liner cover 42 is fittedly secured to the stationary ring 20 to retain the slide ring 40 against detachment. A dust-proof cover 44 is mounted on a somewhat upper portion of the rotary ring 30 to prevent dust from entering through the clearance between the stationary ring 20 and the rotary ring 30. A brake ring 46 is mounted on the bottom of the rotary ring 30. The brake ring 46 is made of an engineering plastic material such as nylon resins. As shown in FIG. 5, the brake ring 46 has a number of blades which constitute an air brake section. The blades 47 extend in the radial direction of the brake ring 46 (i.e., in the radial direction of the rotary ring 30). The brake ring 46 (i.e., the blades 47) thus can provide air braking force to the rotary ring 30 in correspondence to the rotational speed of the rotary ring 30. As shown in FIG. 4, the traveler 50 substantially has a shape of letter C turned down by 90 degrees, and it is fitted on the flange 32 of the rotary ring 30 for revolution relative to the flange 32 in the circumferential direction thereof. As shown in FIGS. 2 and 4, the spinning ring 10 is mounted in the ring rail 74 with the mounting portion 22 of the stationary ring 20 fitted in the mounting hole 75 of the ring rail 74 such that the mounting surface 24 rests on a base surface portion adjacent the mounting hole 75 and with a rubber set ring 90 fitted in a set ring receiving groove 26. As described above, the spindle 80 and the bobbin 82 extend through the rotary ring 30 (i.e., the central axis portion thereof). The relationship among the stationary ring 20, the rotary ring 30 and the traveler 50 of the spinning ring 10 is as follows. When the bobbin 82 reaches the normal operating speed at 10,000 to 15,000 rotations/min. (but not always after the normal operating speed is reached), the rotary ring 30 is rotated such that the speed or revolution of the traveler 50 relative to the rotary ring 30 is made substantially zero, so that the traveler 50 and the rotary ring 30 are rotated substantially in unison with each other (i.e., substantially at the same speed) relative to the stationary ring 20. In other words, the resultant of the frictional resistance of the rotary ring 30 developed to the slide ring 40 and the rotational resistance produced by air around the brake ring 46 and developed to the rotation of the rotary ring 30, is set such that the traveler 50 and the rotary ring 30 are rotated substantially at the same speed relative to the stationary ring 20. The functions and effects of the spinning ring 10 will now be described. As described before, as shown in FIGS. 1, 3 and 4, with the rotation of the spindle 80 and the bobbin 82, the yarn T (i.e., the raw yarn T1) fed from the raw yarn bobbin (yarn feeder) 70 is drafted by the drafting device 72 and is guided through the through hole 77 of the guide member 76 and the traveler 50 of the spinning ring 10 to be taken up on the bobbin 82 while being twisted. With the start of rotation of the bobbin 82, the traveler 50 starts to undergo revolution, and the rotary ring 30 is caused to be rotated relative to the stationary ring 20 by the frictional resistance between the traveler 50 and the rotary ring 30. As a result, the revolution (i.e., absolute speed) of the traveler 50 relative to the stationary ring 20 is distributed into the rotation of the rotary ring 30 relative to the stationary ring 20 and the revolution (i.e., relative speed) of the traveler 50 relative to the rotary ring 30. This means that high speed rotation of the bobbin 82 does not bring about a corresponding high speed of revolution of the traveler 50 relative to the rotary ring 30. Thus, it is possible to improve the production efficiency by increasing the rotational speed of the bobbin 82. When the bobbin 82 reaches the high speed and normal operating speed at 10,000 to 15,000 rotations/min., the speed of the traveler 50 relative to the rotary ring 30 is substantially zero, that is, the traveler 50 and the rotary ring 30 are rotated substantially in unison with each other (or substantially at the same speed) relative to the stationary ring 20. The traveler 50 thus does not receive much frictional force produced between the traveler 50 and the rotary ring 30. The burden (or degree of damage) of the traveler 50 is reduced, so that its life can be extended. At the time of the start of rotation (i.e., acceleration) of the traveler 50, the rotary ring 30 may not be rotated at the same speed as the traveler 50. However, when the revolution of the traveler 50 reaches substantially the normal operating speed, the rotary ring 30 is rotated substantially at the same speed as the traveler 50. The slide ring 40 that is interposed between the stationary ring 20 and the rotary ring 30, permits smoother rotation of the rotary ring 30 compared to the case where the rotary ring 30 is in direct sliding contact with the stationary ring 20. With the rotation of the rotary ring 30 in unison with the traveler 50, the slide ring 40 receives impact force in its radial direction. However, since the slide ring 40 has a cut section 40a, it can be elastically deformed to increase or reduce the clearance of the cut section 40a. The slide ring 40 thus can be elastically expanded or contracted just like a spring, so that it can absorb the impact force from the rotary ring 30 with its elastic deformation to reduce the degree of re-transfer of the impact force from the rotary ring 30 back to the same. Impact force thus is not transferred back to the rotary ring 30 so much, and smooth high speed rotation of the rotary ring 30 can be ensured. The cut section 40a of the slide ring 40 has the following advantage. In the manufacture of the spinning ring 10, the slide ring 40 can be readily fitted on the one-piece rotary ring 30 (i.e., in the slide ring inner portion receiving recess 31 thereof) by elastically deforming it such as to expand the clearance of the cut section 40a. With a slide ring 40 which does not have any cut section 40a, the rotary ring 30 has to be produced as a first portion 30a and a second portion 30b, as shown in FIG. 8. In this case, the slide ring 40 is assembled by separating the first portion 30a and the second portion 30b from each other, and afterwards the first portion 30a and the second portion 30b are coupled together. With this construction, however, the accuracy of the rotary ring 30 is sacrificed to result in deterioration of the performance of the spinning ring 10. The present spinning ring 10 is free from such disadvantage because the slide ring 40 has the cut section 40a. As described above, when the bobbin 82 is rotating at high speed, the traveler 50 is also undergoing revolution at high speed. The brake ring 46 thus applies a strong braking force to the rotary ring 30. Besides, since the traveler 50 is undergoing revolution substantially at the same high speed as the rotary ring 30, a strong centrifugal force is exerted to the traveler 50, which is thus undergoing revolution in unison with the rotary ring 30. Consequently, a strong braking force is exerted to the traveler 50 by the brake ring 46. When the bobbin 82 is rotated at high speed so that the yarn T undergoes revolution at high speed in unison with the traveler 50 and the rotary ring 30, the yarn T experiences a great centrifugal force and is expanded between the through hole 77 of the guide member 76 and the traveler 50, as shown in FIG. 7. When the yarn T is strongly brought into contact with a separator 95 as shown by broken lines in FIG. 7, it may be broken by the contact resistance. In the present spinning ring 10, however, owing to the braking force applied to the rotary ring 30 and the traveler 50 as noted above, the yarn T is always pulled by a predetermined pulling force. This has an effect of suppressing the ballooning to be small as shown by broken lines in FIG. 7. Thus, excessively forced contact of the yarn T with the separator 95 is prevented to prevent breakage of the yarn T, so that smooth spinning operation can be ensured. When the rotary ring 30 and the traveler 50 are stopped after delay when the spindle 80 and the bobbin 82 are stopped (over-run rotation), the yarn T is disturbed in the neighborhood of the traveler 50 (snarl phenomenon). In the present spinning ring 10, such snarl phenomenon can be prevented by the braking force acting on the rotary ring 30 and the traveler 50 as described above. Further, as described above, the slide ring 40 is interposed between the stationary ring 20 and the rotary ring 30 such as to minimize the rotational resistance of the rotary ring 30. In the manufacture of a large number of spinning rings 10, fluctuations of the rotational resistance developed to the rotary ring 30 are inevitable. Minimization of the rotational resistance developed to the rotary ring 30 results in that the rotational resistance fluctuations can fall within a very fine range. Thus, in the present spinning ring 10, with the rotational resistance developed to the rotary ring 30 minimized to make the rotational resistance fluctuations to be very fine, the rotary ring 30 is given a braking force by the brake ring 46. It is thus readily possible to set the resultant of the rotational resistance with respect to the brake ring 46 and other rotational resistance such that the traveler 50 and the rotary ring 30 are rotated substantially at the same speed relative to the stationary ring 20 when the bobbin 82 reaches the high speed and normal operating speed. Since not only the traveler 50 is under revolution but also the rotary ring 30 is in rotation, great impact force is exerted to the rotating stationary ring 20. In the present spinning ring 10, however, the stationary ring 20 is made of a synthetic resin. Thus, the impact force received by the stationary ring 20 from the rotary ring 30 is not directly transmitted to the ring rail 74 but is transmitted after considerable attenuation, and the degree of retransmission of impact force back to the rotary ring 30 is reduced. Thus, the yarn T (i.e., the spun yarn T2) can be smoothly taken up on the bobbin 82. The revolution of the traveler 50 generating tension in the yarn T (i.e., the spun yarn T2) causes fine precession of the rotary ring 30, thus causing fine precession of the stationary ring 20 relative to the base member. If the stationary ring 20 is entirely made of metal, therefore, its mounting surface 24 (particularly the outer edge thereof) separates the coating of the ring rail 74, thus resulting in rusting of the ring rail portion deprived of the coating. In the present spinning ring 10, the stationary ring 20 is made of a synthetic resin so that impacts exerted to the ring rail 74 are gentle. It is thus possible to prevent separation of the coating from the ring rail 74 and resultant rusting thereof. Modifications of First Embodiment Modifications of the first embodiment will now be described. FIGS. 9 to 13 show slide rings 40A, 40B, 40C, 40D and 40E as modifications of the slide ring 40. The slide ring 40A shown in FIG. 9 has a slanted cut section 40Aa. The slide ring 40B shown in FIG. 10 has a V-shaped cut section 40Ba. The slide ring 40C shown in FIG. 11 has a cut section 40Ca having a staggered shape. The slide ring 40D shown in FIG. 12 has three cut sections 40Da. That is, the slide ring 40D is divided into three distinct ring portions 40Db. Thus, it can be more readily fitted on the rotary ring 30 (i.e., in the slide ring inner portion receiving recess 31). In addition, because the slide ring 40D is divided into three ring portions 40Db, fine movements thereof in the radial direction may be readily caused by impact forces exerted to these ring portions 40Db in the radial direction. With such fine movements, the impact force from the rotary ring 30 can be readily absorbed. Besides, smooth rotation of the rotary ring 30 can be ensured. The slide ring 40D may not be divided into three ring portions but may be divided into any other number of ring portions as well. The slide ring 40E shown in FIG. 13 has not a cut section, but it has one or more thin portions 40Ea. The thin portion or portions 40Ea can be more readily elastically deformed than other portions and thus can absorb more impact force generated with the rotation of the rotary ring 30. The illustrated sectional shape of the slide ring 40E is by no means limitative, and it is possible as well to adopt various other sectional profiles, such as rectangular, circular and oval ones. FIGS. 14 and 15 show brake rings 46A and 46B as modifications of the brake ring 46. The brake ring 46A shown in FIG. 14 has a plurality of circumferentially spaced-apart blade sections 47A each having a pair of semi-cylindrical blades 47Aa and 47Ab in back-to-back arrangement. The brake ring 48B shown in FIG. 15 has a plurality of blades 47B which are wavy in bottom view. Second Embodiment A spinning ring 110 according to a second embodiment of the invention will now be described with reference to FIGS. 16 to 19. The differences of this embodiment from the spinning ring 10 of the first embodiment will be mainly described. As shown in FIG. 16, this spinning ring 110 again comprises a stationary ring 120, a rotary ring 130 and a traveler 150. The traveler 150 is mounted on a flange portion 132 of the rotary ring 130 for revolution in the circumferential direction of the flange portion 132. A slide ring 140 is interposed between the stationary ring 120 (i.e., a slide ring outer portion receiving recess 121) and the rotary ring 130 (i.e., a slide ring inner portion receiving recess 131). The slide ring 140 has a pentagonal (accurately hexagonal) section as shown and, as shown in FIG. 17, has a cut section 140a. Turning to FIG. 16, a liner cover 142 is fittedly secured to the stationary ring 120, and a dust-proof cover 144 is mounted on the rotary ring 130. A brake ring 146 is secured to a bottom portion of the rotary ring 130. As shown in FIGS. 16 and 18, the brake ring 146 has a lower flange portion 146a, and a plurality of brake elements 148 (FIG. 19) are rotatably mounted by pins 148b on the flange portion 146a. The brake elements 148 can be advanced and retreated in the radial direction of the rotary ring 130. Each brake element 148 has a contact portion 148a as an end portion opposite the pin 148b. The brake element 148 is advanced by a centrifugal force generated with the rotation of the rotary ring 130. In its retreated state (as shown by solid lines in FIG. 18), the contact portion 148a of each brake element 148 is not in contact with the inner peripheral surface 123 of the stationary ring 120. When the rotary ring 130 is rotated to advance the brake elements 148 (as shown by broken line in FIG. 18), the contact portion 148a of each brake element 148 is brought into contact with the inner surface 122 of the stationary ring 120. The present spinning ring 110 will now be described mainly in connection with its peculiar functions and effects. With the start of rotation of the bobbin 82, the traveler 150 starts revolution, and frictional resistance between the traveler 150 and the rotary ring 130 causes rotation of the rotary ring 130 relative to the stationary ring 120. When the bobbin 82 reaches its high speed and normal operating speed, the traveler 150 and the rotary ring 130 are rotated substantially at the same speed and substantially in unison with each other relative to the stationary ring 120. With the rotation of the rotary ring 130 and according to the rotational speed thereof (to be exact, in proportion to the square of the rotational speed), a centrifugal force is applied to each brake element 148 of the brake ring 146, and this centrifugal force causes each brake element 148 to be advanced (each brake element 148 reaching the advanced state shown by broken line in FIG. 18). Thus, the contact portion 148a of each brake element 148 is brought into contact with the inner surface 123 of the stationary ring 120. As a result, a frictional force is generated between the brake ring 146 (i.e., each brake element 148) and the stationary ring 120, and the rotary ring 130 receives a braking force corresponding to its rotational speed. This braking force causes a braking force to be applied to the traveler 150 in unison with the rotary ring 130. Thus, the ballooning of the yarn T is suppressed to be small to prevent breakage of the yarn. Modifications of Second Embodiment Modifications of the second embodiment will now be described with reference to FIGS. 20 to 28. FIGS. 20 to 25 show modifications of the rotary ring 130 or the brake ring 140. FIGS. 20 and 21 show a rotary ring 130A. FIGS. 22 and 23 show a brake ring 148B. FIGS. 24 and 25 show a brake ring 148C. FIGS. 26 to 28 show a slide ring 240 as a modification of the slide ring 140. The rotary ring 130A shown in FIG. 20 has no member corresponding to the brake ring 146 described above. Instead, a plurality of brake elements 148A are directly mounted on the rotary ring 130A. Specifically, the rotary ring 130A has its outer periphery lower portion formed with an annular recess 147A as brake element assembling recess, and brake elements 148A (FIG. 21) are each movably mounted by a pin 148Ab in the recess 147A. A centrifugal force generated with the rotation of the rotary ring 130A causes each brake element 148A to be projected to bring a contact portion 148Aa thereof into contact with the inner surface 123 of the stationary ring 120, thus generating a frictional force. The brake ring 146B shown in FIG. 22, like the brake ring 146 shown in FIG. 18, is assembled on the rotary ring 130. The body 146Bb of the brake ring 146B has a lower outer flange portion 146Ba and a plurality of recesses 147B communicating with the flange portion 146Ba. Each brake element 148B (FIG. 23) has a fist-like stem 148Bb which is rotatably fitted in each recess 147B. Each brake element 148B thus can be advanced and retreated relative to the brake ring 146B. Rotation of the rotary ring 130 causes each brake element 148B to be advanced so that the contact portion 148Ba thereof is brought into contact with the inner surface 123 of the stationary ring 130 to generate a frictional force. The brake ring 146C shown in FIG. 24 has a lower outer flange portion 146Ca which in turn has a plurality of recesses 147C of substantially T-shaped configuration in top view. The recess 147C has a pair of stopper portions 147Ca, and it also has a play space 147Cb extending in the radial direction of the brake ring 146C. Each brake element 148C (FIG. 25) corresponds in shape to the recess 147C, that is, it is substantially T-shaped in top view, and its stem has a pair of stopper portions 148Cb. Each brake element 148C is fitted in each recess 147C for advancement and retreat through the play space 147Cb. The brake element 148C is retained against detachment by the stopper portions 147Ca of the recess 147C and the stopper portions 148Cb of the brake element 148C. Rotation of the rotary ring 130 causes each brake element 148C to be advanced to bring the contact portion 148Ca thereof into contact with the inner surface 123 of the rotary ring 130, thus generating a frictional force. The spinning ring 210 shown in FIG. 26 features a slide ring 240 (FIGS. 27 and 28). The slide ring 240 comprises a main ring 241 and a reinforcement ring 243. The main ring 241 has substantially the same construction as the slide ring 140 (FIG. 17) described before, and has a smaller outer diameter than the reinforcement ring 243. The main ring 241, like the slide rings 40 and 140 shown in FIGS. 6 and 17, respectively, are made of engineering plastic material, elastomer or metal which is elastic, heat-resistant and wear-resistant as well having very low coefficient of friction, and has a cut section 241a. The reinforcement ring 243 has a simple ring-like form and is made of an engineering plastic material which is particularly excellent in mechanical strength. The main ring 241 and the reinforcement ring 243 have different vibration attenuating characteristics. The slide ring 240 is obtained by loosely fitting the reinforcement ring 243 on the main ring 241. The slide ring 240 has the following peculiar functions and effects. The slide ring 240 (140) is rotated with the rotation of the rotary ring 130 (FIGS. 28 and 16). The slide ring 140 (FIG. 17) noted above can be expanded by the centrifugal force generated with the rotation of the rotary ring 130, so that it may be in forced contact with the rotary ring 120 (i.e., the slide ring outer portion receiving recess 121). As a result, the frictional force (or sliding resistance) between the stationary ring 120 and the slide ring 140 may be increased to prevent smooth rotation of the rotary ring 130. The main ring 241 of the slide ring 240 (FIG. 8), however, is not expanded beyond a predetermined diameter by virtue of the reinforcement ring 243. This means that the slide ring 240 itself is not expanded beyond a predetermined diameter, so that it is prevented from being in forced contact with the stationary ring 120 (i.e., the slide ring outer portion receiving recess 121). Thus, smooth rotation of the rotary ring 130 is ensured. Besides, the different vibration attenuating characteristics of the main ring 241 and the reinforcement ring 243 permit more effective attenuation of vibrations. Third Embodiment A spinning ring 310 according to a third embodiment of the invention will now be described with reference to FIG. 29. The differences from the spinning ring 10 of the first embodiment will be mainly described. The spinning ring 310 again comprises a stationary ring 320, a rotary ring 330 and a traveler 350. The traveler 350 is mounted on a flange portion 332 of the rotary ring 330 for revolution relative thereto. The rotary ring 330 comprises a first part 330a and a second part 330b, these parts 330a and 330b being separate members. The rotary ring 330 (i.e., the first part 330a thereof) has a dust-proof flange portion 344. The stationary ring 320 has an inner ring-like ridge 325 formed on substantially a central portion of its inner peripheral surface in the height direction. Slide rings 340 are each disposed on and under the ring-like ridge 325 and between the stationary ring 320 and the rotary ring 330. The slide rings 340, like the slide ring 40 (FIG. 4) noted above, are capable of sliding relative to both the stationary ring 320 and the rotary ring 330. With this spinning ring 310, the following peculiar functions and effects are obtainable. With the revolution of the traveler 350 generating tension in the yarn. T (i.e., the spun yarn T2), the rotary ring 330 tends to undergo fine precession (see the spinning ring 10 in FIG. 4). In this spinning ring 310, however, such precession is prevented owing to the two slide rings 340 which are provided in a predetermined spacing in the central axial direction (i.e., in the vertical direction) of the stationary ring 320 and the rotary ring 330. Accurate rotation of the rotary ring 330 about the central axis thereof thus can be ensured. Without precession of the rotary ring 330, it is possible to ensure uniform and smooth high speed revolution of the traveler 350. In addition, without precession of the rotary ring 330, the friction (i.e., rotational resistance) with respect to the stationary ring 320 is not increased, so that it is possible to ensure smooth high speed rotation of the rotary ring 330. While in the spinning ring 10 (FIG. 4), the stationary ring 20 and the rotary ring 30 provide shearing forces to the slide ring 40, in the present spinning ring 310, the stationary ring 320 and the rotary ring 330 provide compressive forces. The slide ring (10, 310, etc.) is stronger in mechanical strength with respect to compressive force than with respect to shearing force. Thus, the durability of the slide ring 340 can be improved. Modification of Third Embodiment A modification of the spinning ring 310 of the third embodiment, i.e., a spinning ring 410, will now be described with reference to FIG. 30. The spinning ring 410 again comprises a stationary ring 420, a rotary ring 430 and a traveler 450. The traveler 450 is mounted for revolution on a flange portion 432 of the rotary ring 430. The rotary ring 430 has a ring-like ridge 435 formed on its outer peripheral surface. Slide rings 440 are each disposed on and under the ring-like ridge 435 and between the stationary ring 420 and the rotary ring 430. The slide rings 440, like the slide ring 40 (FIG. 4) noted above, are capable of sliding relative to both the stationary ring 420 and the rotary ring 430. The rotary ring 430 is provided with a dust-proof cover 440, and the stationary ring 420 is provided with a liner cover 442. Again in this spinning ring 410, like the previous spinning ring 310 (FIG. 29), precession of the rotary ring 430 can be prevented. In addition, in the preceding spinning ring 310 (FIG. 29), the rotary ring 330 comprises the first part 330a and the second part 330b which are separated from each other for assembling the slide rings 340 and which are subsequently coupled together. The present spinning ring 410 has an advantage that the slide rings 440 can be assembled on the rotary ring 410 which is a one-piece member.

Claims: A spinning ring (10, 110, 210, 310, 410) for winding yarn (T) fed from a yarn feeder (70) on a bobbin (82), comprising: a stationary ring (20, 120, 320, 420) mounted on a base member (74), a rotary ring (30, 130, 330, 430) disposed inside and concentrically with the stationary ring for rotation about the central axis thereof, the bobbin (82) being disposed inside and concentrically with the rotary ring for rotation about the central axis thereof, and a traveler (50, 150, 350, 450) disposed on the rotary ring for revolution in the circumferential direction of the rotary ring to guide the yarn (T) fed from the yarn feeder (70) with respect to the bobbin (82), a slide ring (40, 40A-E, 140, 240, 340, 440) for mounting the rotary ring (30, 130) on the stationary ring (20, 120), and a brake section (46; 46A,B; 146; 130A, 148A; 146B; 146C) for applying a braking force to the rotary ring in response to the rotation of the rotary ring, characterized in that the slide ring (40, 40A-E, 140, 240, 340, 440) and the brake section (46; 46A,B; 146; 130A, 148A; 146B; 146C) on the one hand and the rotary ring (30, 130, 330, 430) and the traveler (50, 150, 350, 450) on the other hand are formed such that, at normal operating speed, the resistance developed by the slide ring and the brake section to the rotation of the rotary ring is smaller than the friction between the rotary ring and the traveler caused by the centrifugal force exerted to the traveler so that the speed of the traveler relative to the rotary ring is zero and the traveler and the rotary ring rotate in unison with each other relative to the stationary ring (20, 120, 320, 420). The spinning ring according to claim 1, wherein the air brake section (46, 46A, 46B) is mounted to the rotary ring (30) and applies the braking force to the rotary ring, the air brake section comprising a plurality of blades (47, 47A, 47B) extending in radial directions of the rotary ring. The spinning ring according to claim 1, wherein the brake section (146; 130A, 146A; 146B, 146C) is provided on the rotary ring (130, 130A) for applying the braking force to the rotary ring, and the brake section comprises a plurality of brake elements capable of advancing and withdrawing in a radial direction relative to the rotary ring, the brake elements being advanced in a centrifugal direction by centrifugal force generated by the rotation of the rotary ring, wherein the advanced brake elements contact the stationary ring. The spinning ring according to one of claims 1 to 3, characterized in that the slide ring has a single cut section (40a, 40Aa, 40Ba, 40Ca). The spinning ring according to one of claims 1 to 3, characterized in that the slide ring (40D) is divided into a plurality of ring portions (40Db). The spinning ring according to one of claims 1 to 3, characterized in that the slide ring (40E) has a portion (40Ea) thinner than other remaining portions. The spinning ring (210) according to one of claims 1 to 3, characterized in that the slide ring (240) comprises a main ring (241) made of an elastic material and having a cut section (241a) and a reinforcement ring (243) without any cut section and fitted on the main ring. The spinning ring according to claim 7, wherein the main ring and the reinforcement ring have different vibration attenuation characteristics. The spinning ring (310, 410) according to one of claims 1 to 3, characterized in that a plurality of the slide rings (340, 440) are disposed at a predetermined interval in the central axial direction of the stationary ring and the rotary ring which are capable of being in sliding contact with both the rings. The spinning ring according to any one of the preceding claims, wherein the slide rings are made of an elastic synthetic resin, an elastomer or a metal. The spinning ring according to any one of the preceding claims, wherein the stationary ring is mounted in the base member (74) such that it is fitted in a mounting hole (75) in the base member, at least a portion of the stationary ring that is in contact with the base member being made of a synthetic resin. The spinning ring according to any one of the preceding claims, wherein the rotary ring is a one-piece molding.

Inventors: IWAMA YASUSHI, IWAMA, YASUSHI
Applicants: NIPPO SANGYO, NIPPO LTD.
Application year: 1995
Main classification: D01H7
IPC codes: D01H7