Method and Device for Preventing Creation of Fuzzy Fibers of Yarn During Twisting Operation of the Multiple Twister

The present invention relates to a method and device for preventing creation of fuzzy fibers of yarn during twisting operation in the multiple twister, more particularly in the double twister.

In the conventional double twister, wherein a hollow spindle is provided with a reserve disc disposed at a position between a spindle wharve and thereof, and a protection pot is coaxially mounted on the spindle via bearing means in such a condition that a supporting cylindrical portion formed therein is mounted on the spindle in such a condition that it is capable of stationary positioning during driving of the spindle, a hollow entry tube is stationarily mounted on the supporting cylindrical portion and the hollow entry tube extends upwards along the axial direction of the spindle; the reserve disc is provided with a yarn guide passage radially extending from the center thereof and the yarn guide passage is connected to a bottom aperture of the hollow spindle, a yarn taken from a yarn package held by the protection pot is introduced into the entry tube via a guide bush stationarily mounted on the top end of the entry tube, then the yarn is led toward the yarn guide passage of the reserve disc which is rotating with the spindle, thereafter the yarn is taken from an outlet of the yarn guide passage and led to a yarn guide stationarily disposed above the hollow yarn guide bush along an extended line of the common longitudinal axis of the entry tube and the spindle, and; finally the twisted yarn is wound on a package. During the above-mentioned twisting operation, when the yarn introduced into the hollow entry tube, is led to a tip of the hollow spindle, the yarn passes through an intermediate member disposed between the entry tube and the spindle so as to control the yarn tension. When the yarn taken from the yarn guide passage of the reserve disc is led to the hollow yarn guide disposed above the entry tube, the yarn passes at least one time through a yarn passage formed on the entire peripheral surface of the tension disc so as to regulate the yarn tension. The above-mentioned intermediate member is provided with a capsule which creates a particular yarn passage to create yarn tension. Since the reserve disc is continuously rotated together with the spindle at a constant driving speed, when the yarn passes through a yarn passage between the above-mentioned intermediate member and the bottom aperture of the hollow spindle (hereinafter referred to as a first twisting passage), the yarn is twisted; while, when the yarn passes through a yarn passage between the outside aperture of the yarn guide passage of the reserve disc and the hollow yarn guide disposed above the entry tube (hereinafter referred to as a second twisting passage), the yarn is twisted. Consequently, the yarn is provided with two twisting times every revolution of the reserve disc, in other words, one turn of twist is imported to the yarn in the first twisting passage while another one turn of twist is imparted to the yarn in the second twisting passage. In the above-mentioned conventional double twister, a deflection plate is formed at a bottom portion of the hollow spindle in such a condition that the deflection plate extends radially from the central axis of the spindle and the outside edge thereof is extended outside from the deflection plate. Consequently, when the yarn passes through the second twisting passage, a ballooning of the yarn is formed between the outside edge of the deflection plate and the hollow yarn guide.

In the above-mentioned double twister, when a spun yarn is utilized as a material yarn, the material yarn is provided with a fuzzy appearance because of abrasion of the yarn during the previous yarn processing such as the winding operation for forming the yarn package. When the above-mentioned material yarn undergoes the twisting operation by the double twister, the yarn is subjected to an abrasion action when the yarn is introduced into the entry tube via the yarn guide bush and, consequently, there is a possibility that the fuzzy appearance of the yarn will become more distinguished. Further, when the yarn passes through the yarn passage formed on the peripheral surface of the reserve disc, since the yarn slides on the peripheral surface of the reserve disc, a certain abrasion action is also imparted to the yarn and, therefore the processing yarn is additionally provided with fuzzy fibers projecting from the surface thereof. The above-mentioned phenomenon of creating fuzzy fibers is possibly enhanced by the influence of static electricity which is created by the sliding contact of the yarn with the above-mentioned yarn guide bush on the peripheral surface of the reserve disc. Consequently, the twisted yarn produced by the above-mentioned double twister becomes a distinguished fuzzy yarn and such fuzzy twisted yarn creates troubles such as frequent yarn breakages in the weaving or knitting process, disturbance to the smooth operation of the carriage during the knitting operation, and possible entanglement of adjacent yarns during the weaving operation by which the quality of the woven fabric is degraded.

To remove the above-mentioned fuzzy fibers from the twisted yarn, some finishing treatment such as a singeing operation is sometimes applied to the yarn. However, such after treatment of the twisted yarn increases the cost of the yarn and, as a result, the after treatment for removing the fuzzy fibers from the twisted yarn has not been applied except when the yarn is produced for particular purposes, for example for producing a sewing thread. With regard to the device for removing or eliminating the fuzzy fibers of the twisted yarn, there is at present no effective device which can be applied to the multiple twister such as the double twister. In view of the above, it is the principle object of the present invention to provide a method and device for preventing creation of fuzzy fibers on a yarn during the twisting operation of the multiple twister such as a double twister. To attain the purpose of the present invention, the fuzzy fibers projecting outside from the surface of yarn passes through either one of the above-mentioned twisting passges or both of these twisting passages. In the device according to the present invention, a particular member for twisting the fuzzy fibers into the main body of the yarn is disposed at a position along the yarn passage downstream from the yarn passage formed in the entry tube. One of the particular members is a contacting member which strokes the fuzzy fibers so as to attach the free portion of the fuzzy fibers to the main body of the yarn. In the present invention, an oiling member, which is disposed along the passage between the entry tube and the spindle, is used for eliminating the fuzzy fibers in the twisting operation.

FIG. 1 is a view in axial section through a double twister embodying the device of the present invention.

FIG. 2 is a perspective view of a yarn fed into the double twister from a yarn package mounted on the double twister.

FIG. 3 is an axial cross-sectional view of an entry tube of the double twister shown in FIG. 1.

FIG. 4 is an axial cross-sectional view of a part of a feed bushing provided with a contacting member, applied to the double twister shown in FIG. 1.

FIGS. 5, 6, 12 and 13 are axial cross-sectional views of the other embodiments of the contacting member according to the present invention.

FIGS. 7, 9, 11, 14, 17, 21 and 22 are axial cross-sectional views of a part of the feed bushing provided with the respective modified contacting member, applied to the double twister shown in FIG. 1.

FIG. 8 is a cross-sectional view of the feed bushing, taken along the line IIX-- IIX in FIG. 7.

FIG. 10 is a cross-sectional view of the feed bushing, taken along the line X-- X in FIG. 9.

FIG. 15 is a cross-sectional view of the feed bushing, taken along the line XV-- XV in FIG. 14.

FIG. 16 is an enlarged view of the relative arrangement of the contacting member, taken from an axially upward position thereof, in FIG. 14.

FIGS. 18, 19 and 20 are cross-sectional views of the feed bushing taken along the line IIXX-- IIXX, the line IXX-- IXX, the line XX, in FIG. 17.

FIG. 23 is a cross-sectional view of the contacting member shown in FIG. 22, which indicates the shape of the yarn passage therein.

FIGS. 24, 25, 26, 28 and 29 are sectional views of the yarn guide disposed at a position above the entry tube of the double twister, according to the present invention.

FIG. 27 is an enlarged cross-sectional view of a part of the yarn guide shown in FIG. 26.

FIG. 30 is a plan view of the yarn guide shown in FIG. 29.

FIG. 31 is a schematic cross-sectional view of the double twister embodying the device of the present invention.

FIG. 32 is an explanatory diagram indicating the relation between the yarn tension and the positions along the yarn passage in the double twister shown in FIG. 31.

FIG. 33 is a view in axial section through another type of double twister embodying the device of the present invention.

FIG. 34 is a plan view of a part of the double twister shown in FIG. 33.

FIG. 35 is an axial cross-sectional view of a part of the double twister shown in FIG. 33.

FIG. 36 is an axial cross-sectional view of a part of a double twister, which is a modification of the double twister shown in FIG. 33.

FIG. 37 is an exploded view of a part of a tenser container shown in FIG. 36.

FIG. 38 is a view in axial section through a double twister, which is a modification of the double twister shown in FIG. 34.

FIGS. 39, 41, 42 and 43 are cross-sectional views of oiling devices, provided with a contacting member, applied for the double twister shown in FIG. 38.

FIG. 40 is a cross-sectional view of the oiling device, taken along the line XXXX-- XXXX in FIG. 39.

The construction and function of the device applied to the double twister is hereinafter explained in detail. The general construction of the above-mentioned modified double twister is shown in FIG. 1, wherein an assembled portion, except the entry tube, spindle, reserve disc, deflection plate and the yarn guide disposed above the entry tube, may be understood as being composed of novel members introduced by the present invention.

In the modified double twister shown in FIG. 1, a spindle wharve 1 is driven by a driving belt 2, and a spindle 6 is mounted on the spindle wharve 1 in upright condition via a reserve disc 3 and a deflection plate 5. These members, that is, the spindle 6, the reserve disc 3 and the deflection plate 5 are provided with a common upright rotational axis which is also the rotational axis of the spindle wharve 1 and these members are assembled as one body. The spindle 6 is provided with an upright hollow yarn pasage 6a formed along the above rotational axis thereof and the reserve disc 3 is provided with a yarn guide passage 4 extending from the rotational axis thereof to an outside edge thereof. This yarn guide passage 4 is connected to the bottom aperture of the hollow yarn passage of the spindle and is provided with an outlet aperture 4a. The deflection plate 5 is coaxially and radially extended from the bottom portion of the spindle 6 and the edge 5a of the deflection plate 5 is located at a position outside the edge of the reserve disc 3. A protection pot 7, provided with a cylindrical tube portion 7a, is coaxially mounted on the spindle 6 in such a condition that the cylindrical tube portion 7a is supported by the spindle 6 via a pair of bearings 8a and 8b. A yarn package 10 is coaxially mounted on the cylindrical tube portion 7a of the protection pot 7 as shown in FIG. 1. A cylindrical balloon control member 11 is disposed by a supporting bracket (not shown) in such a condition that the cylindrical balloon control member 11 is coaxially positioned outside the protection pot 7 in stationary condition. A plurality of magnetic members 12a and 12b are rigidly mounted on the balloon control member 11 and the protection pot 7, respectively, in such a condition that one of the magnetic members 12a adjacently faces one of the magnetic members 12b. Consequently, the protection pot 7 can be held stationary during the driving of the spindle 6 by the magnetic action between these magnetic members 12a and 12b. A feed bushing 13 is provided with an upper and lower cylindrical portion 13a and 13b and the lower cylindrical portion 13b is rigidly mounted on the top end portion of the cylindrical tube portion 7a. A tenser container 14 is rigidly inserted into the upper cylindrical portion 13a and a small cylindrical member 15, made of a material having low frictional resistance, for example an alumina-ceramic, is rigidly inserted into the bottom portion of the tenser container 14. An entry tube 16 is movably supported by the tenser container 14 in such a way that the entry tube 16 is capable of displacing upward or downward in the tenser container 14. The top end portion of the entry tube 16 is projected upward from the upper horizontal edge of the protection pot 7. A capsule 17 is disposed in a space 14b formed in the tenser container 14 in such a condition that the capsule 17 contacts the bottom end of the entry tube 16 and the small cylindrical member 15. The entry tube 16 is provided with a laterally expanded portion 16a formed at a bottom end thereof and the tenser container 14 is provided with a laterally expanded portion 14a formed at a top head portion thereof so that a cylindrical space is formed between the tenser container 14 and the entry tube 16. A compressed helical spring 18 is coaxially mounted on the entry tube 16 at the above-mentioned cylindrical space so that the entry tube 16 always urges the capsule 17 downward. As shown in FIG. 1, the entry tube 16 is provided with a yarn passage 16b coaxially formed along a longitudinal axis thereof, while the feed bushing 13 is provided with a central yarn passage 13c formed at an intermediate portion between the upper and lower cylindrical portions 13a and 13b. The top portion of the cylindrical tube portion 7 a is provided with a central aperture 7c. The yarn passage 16a and the small cylindrical member 15, and the central yarn passage 13c and the central aperture 7c are aligned along a common central axis of the assembly thereof. A yarn 19 fed into the entry tube 16 passes through the yarn passage 16a and is introduced into the hollow yarn passage 6a of the spindle 6 via the space 14b, the small cylindrical member 15, the central yarn passage 13c and the central aperture 7c. Since the capsule 17 is sandwiched by the bottom end of the entry tube 16 and the small cylindrical member 15, the yarn 19 passes through the contactng portions between the entry tube 16 and the capsule 17, and between the small cylindrical member 15 and the capsule 17, and the yarn 19 is stretched when the yarn 19 passes through the above-mentioned contacting portions.

A flyer 20 is turnably mounted on the entry tube 16 at a position right above the tenser container 14 and the yarn 19 taken from the yarn package 10 is led to a yarn guide bushing 22 via a small yarn guide (not shown) formed at a free end of the flyer 20. A yarn guide 21 is disposed at a position coaxially above the yarn guide bushing 22. The yarn 19 is delivered from the outlet aperture 4a of the yarn guide passage 4 of the reserve disc 3 passes along a yarn passage formed on the entire peripheral surface of the reserve disc 3 at least one time and, then, is led to the yarn guide 21 while passing through a cylindrical space formed between the protection pot 7 and the balloon control member 11. Thereafter the twisted yarn is wound on a bobbin (not shown) by means of a winding device (not shown).

When the spindle wharve 1 is turned one revolution by the driving belt 2, the reserve disc 3, deflection plate 5 and the spindle 6 are turned one revolution toward the same turning direction as the spindle wharve 1. When the yarn 19 passes through the space 14b of the tenser container 14, the yarn 19 is gripped in sliding condition at the contacting point between the upper portion of the capsule 17 and the bottom portion of the entry tube 16, while also being gripped in sliding condition at the contacting point between the lower portion of the capsule 17 and the small cylindrical member 15, consequently, a ballooning of the yarn 19 is formed around the capsule 17 in the space 14b. Since the reserve disc 3 rotates the yarn 19 is twisted at the yarn passage between the contacting point of the lower portion of the capsule 17 with the small cylindrical member 15 and the bottom end portion of the upright yarn passage 6a of the spindle 6 in such a condition that the twisting of the yarn 19 is concentrated at the above-mentioned contact point in the yarn passage. When the above-mentioned firstly twisted yarn (designated 19a in the drawings) is led to the yarn guide 21 via the yarn passage formed on the peripheral surface of the reserve disc 3, the first twisted yarn 19a forms a large ballooning in the cylindrical space between the protection pot 7 and the balloon control member 11. Consequently, the first twisted yarn 19a is secondly twisted by the above-mentioned ballooning and this second twisting of the yarn is concentrated at the contacting point of the yarn 19a with the yarn guide 21. THe secondly twisted yarn (designated 19b in the drawings) passes through the yarn guide 21 and is taken-up by a winding mechanism (not shown), and a yarn package (not shown) is formed from the secondly twisted yarn 19b. In the above-mentioned second twisting, turning of the yarn 19a about the longitudinal axis thereof is transmitted from the yarn guide 21 to the deflection plate 5. As mentioned above, in the modified double twister, the first twisting is applied to the yarn 19 in the yarn passage between the capsule 17 and the bottom end portion of the upright yarn passage 6a of the spindle, and the second twisting is applied to the firstly twisted yarn 19a in the yarn passage between the outlet aperture 4a of the yarn passage 4, formed in the reserve disc 3, and the yarn guide 21.

In the above-mentioned modified double twister, the yarn guide bushing 22 is useful to prevent the creation of fuzzy fibers on the surface of the yarn 19. When the yarn 19 taken from the yarn package 10 is introduced into the entry tube 16, the yarn 19 strongly rubs against the top edge of the entry tube 16 if such yarn guide bush 22 is omitted. In such condition, fuzzy fibers 19c are projected from the main body of the yarn 19 toward the running direction A of the yarn 19, and fuzzy fibers 19d are projected from the main body toward the direction opposite to the running direction A, as shown in FIG. 2. That is, the fuzzy fibers 19c having a leading hook and the fuzzy fibers 19d having a tail hook are projected from the main body of the yarn 19. The yarn guide bushing 22 is made of a material such as an alumina-ceramic material or electro-conductive titanium ceramic material, which is provided with very weak frictional resistance to the yarn 19. The yarn guide bushing 22 is provided with a particular shape to weaken the frictional resistance of the yarn guide bushing 22 to the yarn 19, that is, the edge of the top aperture thereof is provided with a smooth trumpet-like surface 22a as shown in FIG. 3. Therefore, when the yarn 19, taken from the yarn package 10, is introduced into the entry tube 16 via the yarn guide bush 22, the yarn 19 passes along the above-mentioned smooth trumpet-like surface 22a so that the rubbing action of the yarn guide bushing 22 is weakened very much. Consequently, the creation of fuzzy fibers 19c, 19d on the yarn surface can be restricted remarkably. Therefore, the above-mentioned yarn guide bushing 22 may be understood as an additional element of the device according to the present invention.

In the present invention, the basic element to attain the purpose of the present invention is applied in the feed bushing 13 as shown in FIGS. 1 and 4. A central aperture 23 is formed in the intermediate portion between the upper and lower cylindrical portions 13a and 13b of the feed bushing 13 along the longitudinal axis of the feed bushing 13. A contacting element 24, which is made of a material such as an aluminum ceramic material or an electro-conductive titanium ceramic material having weak frictional resistance, is rigidly inserted into the central aperture 23. The contacting element 24 comprises a pair of component elements 24a and 24b facing each other in such a condition that the central yarn passage 13c is formed. The central yarn passage 13c forms a meandering yarn passage and the lateral cross section of the yarn passage 13c is round in shape. It is important to provide a contacting surface, which contacts the yarn 19, on each component element 24a, 24b, at different relative positions as shown in FIG. 4. The above-mentioned component elements 24a and 24b are assembled so as to form the above-mentioned meandering yarn passage by means of binding material 25 such as a bonding agent or a plastic material. In the case where the contacting element 24 is made of material having a property capable of absorbing static electricity, such as the electro-conductive titanium ceramic material, since the above-mentioned binding material 25, such as the bonding agent or the plastic material, does not have an electro-conductive property, it is necessary to put an electro-conductive member such as a metallic wire having electro-conductive property into the binding material 25. If this is not done, it is necessary to use a binding material 25 having an electro-conductive property.

When the above-mentioned contactng element 24 is utilized, the yarn 19 having fuzzy fibers 19a, 19b is forced to contact the contacting surfaces of the component elements 24a, 24b while the yarn 19 is turning about its longitudinal axis. Therefore, these fuzzy fibers 19a, 19b are folded toward the yarn surface of the main body of the yarn 19 and twisted into the main body according to the above-mentioned turning motion of the yarn 19. The other embodiments of the contacting element disposed in the feed bushing 13 are shown in FIG. 5 through FIG. 13.

The contacting element 24 shown in FIG. 5 is provided with a construction similar to the embodiment shown in FIG. 4. Consequently, the reference numerals 24a, 24b are used for indicating the component elements identical to the respective elements shown in FIG. 4. In this element, a single contacting surface is formed on the component element 24a. Therefore, it is easier to assemble the component elements 24a and 24b of this element as compared to the embodiment shown in FIG. 4, and the area of the above-mentioned contacting surface is larger than that of the embodiment shown in FIG. 4. Accordingly, even though the yarn 19 contacts only the above-mentioned single contacting surface, the same twisting-in effect of the fuzzy fibers into the main body of the yarn 19 as with the above-mentioned embodiment shown in FIG. 4 can be effected in the utilization of the contacting element shown in FIG. 5.

The contacting element 24 shown in FIG. 6 is made of a material having low frictional resistance such as an aluminum ceramic material or an electro-conductive ceramic material. The contacting element 24 of this embodiment is composed of four cylindrical bodies 26a, 26b, 26c and 26d assembled in zig-zag fashion along the yarn passage formed therein and a pair of contacting planes 27a and 27b are formed in the cylindrical bodies 26b and 26c as shown in FIG. 6. The yarn 19 contacts the contacting planes 27a and 27b successively while passing through the yarn passage formed in the contacting element 24. Consequently, the fuzzy fibers projected from the yarn surface of the yarn 19 are turned toward the surface of the main body of the yarn 19 which is rotating about its longitudinal axis, so that these fuzzy fibers are twisted into the main body of the yarn 19. Since the yarn 19 contacts the contacting surfaces 27a and 27b, respectively, for a time which is comparatively longer than the contacting time in the previous embodiments, preferable twisting-in action of the fuzzy fibers in the main body of the yarn 19 can be attained.

The contacting element shown in FIGS. 7 and 8 are formed in the intermediate portion of the feed bushing 13 as explained hereinafter in detail. In this embodiment, the above-mentioned intermediate portion is divided into an upper portion 28a and a lower portion 28c and a central portion 28b assembled with the upper and lower portions 28a, 28b as shown in FIG. 7. An upper cylindrical yarn guide 31a, an intermediate cylindrical yarn guide 31b and a lower cylindrical yarn guide 31c are inserted into the above-mentioned portions 28a, 28b and 28c, respectively, so as to form a continuous yarn passage having a zig-zag passage. In this zig-zag yarn passage, the yarn 19 contacts firstly a contacting plane 32a formed in the upper yarn guide 31a, secondly contacts a contacting plane 32b formed in the intermediate yarn guide 31b and thirdly contacts a contacting plane 32c formed in the lower yarn guide 31c, successively. These cylindrical yarn guides 31a, 31b and 31c are made of a material having low frictional resistance titanium material. The working effect of the contacting element 24 is quite similar to the embodiment shown in FIG. 6. The relative axial positions of these cylindrical yarn guides 31a, 31b and 31c can be easily changed because of the construction of the portion 28a, 28b and 28c. That is, the upper portion 28a is provided with an annular ring 29 projected downward from the bottom surface thereof and the axial center of the yarn guide 31a is formed eccentrically from the axial center of the annular ring 29; while the center portion 28b is provided with an annular groove 30 formed in the top surface thereof in such a condition that the axial center of the yarn guide 31b is formed eccentrically from the axial center of the annular groove 30, and the annular ring 29 is slidably engaged in the annular groove 30; the intermediate portion 28b and the lower portion 28c are provided with the same type of annular ring 29 and annular groove 30, respectively, and are connected in the same manner as the portions 28a and 28b. Consequently, the zig-zag condition of the continuous yarn passage can be changed by relatively turning at least one of the above-mentioned three portions 28a, 28b and 28c. Therefore, the contacting condition of the yarn 19 with the contacting plane of the yarn guides 31a, 31b and 31c can be easily adjusted. It is one of the major advantage of the present invention that the working effect of contacting element 24 can be easily changed by relatively turning these three portions 28a, 28b and 28c so as to make a suitable contacting condition for the material of the yarn 19.

In the embodiment of the feed bushing 13 shown in FIGS. 9 and 10, the central yarn passage 13c formed in the feed bush 13 is provided with an elliptical lateral cross-section and a plate contacting member 33 is movably inserted into the central yarn passage 13c as shown in FIGS. 9 and 10. An inside surface 33a of the plate contacting member 33 is plated with chrome or is provided with a satin finish and, consequently, the inside surface of the plate contacting member 33 has a property of low frictional resistance. Threaded rods 34 and 36 are mounted on the feed bushing 13 so as to adjust the lateral cross-sectional area of the central yarn passage 13c. Each threaded rod 36 is engaged into a shoe 37 secured to the plate contacting member 33 so that a portion of the member 33 can be displaced toward the right-hand direction in FIG. 9 by turning the rod 36 so as to displace the shoe 37 toward the right-hand direction. On the other hand, the position of each threaded rod 34 is fixed by a fastening nut 35 and a free end thereof is capable of pushing the contacting member 33 and, consequently, the contacting member 33 is capable of displacing toward the left-hand direction in FIG. 9 by turning the rod 34 so as to push the contacting member 33. Accordingly, the transversal position of the contacting member 33 can be partly changed by means of the threaded rods 34 and 36 so as to create the desired actual contacting surface of the member 33. When the yarn 19 passes through the yarn passage 13c, the yarn 19 contacts the above-mentioned contacting surface created by means of the threaded rods 34 and 36 and, therefore, a very effective twisting-in operation of the fuzzy fibers 19a, 19b (FIG. 2) into the main body of the yarn 19 can be carried out. In the above-mentioned embodiment, since the turning torque of the yarn 19 about the longitudinal axis thereof is gradually weakened from the upstream position to the downstream position of the yarn passage 13c, it is preferable to gradually weaken the frictional contact of the yarn 19 against the inside surface of the contacting member 33 from the upstream position to the downstream position of the yarn passage 13c. To create the above-mentioned condition, the threaded rods 34 and 36 are fixed in such a condition that the contacting areas of the inside surface of the contacting member 33, which area are controlled by the respective threaded rods 34, 36, are gradually reduced from the upstream position to the downstream position of the yarn passage 13c.

The embodiment of the feed bushing 13 shown in FIG. 11, is a modification of the embodiment shown in FIG. 9. In this embodiment, the contacting member inserted into the yarn passage 13c is divided into four pieces 38a, 38b, 38c and 38d. The surface condition of each piece 38a, 38b, 38c and 38d is similar to the contacting member 33 shown in FIG. 9. A shoe piece 40 is secured to each piece of the contacting member at the side opposite to the inside surface of each contacting piece 38a, 38b, 38c and 38d. A position fixing threaded rod 41a is engaged into each shoe piece 40 in such a way that the position of the contacting pieces 38a, 38b, 38c and 38d can be fixed by turning the respective threaded rod 41a. In this embodiment, to create a better twisting-in of the fuzzy fibers into the main body of the yarn 19, it is desirable that the transversal cross-sectional area of the yarn passage 13c be gradually increased from the upstream position to the downstream position thereof. Instead of applying the transversal cross-section of the yarn passage 13c having an elliptical shape in the embodiments shown in FIGS. 10 and 11, a round transversal cross-section can be applied for the yarn passage 13c.

In the embodiment of the contacting member shown in FIGS. 12 and 13, the contacting member 24 comprises a pair of guide bushings 42, 43 made of a material having low frictional resistance such as an aluminum ceramic material and a coiled wire 44. In FIG. 12, the coil wire 44 of the contacting member 24 has a particular outer profile wherein the yarn passage formed in the coiled wire 44 is provided with a transversal cross-section which gradually expands from the middle portion thereof to the upstream and downstream end portion thereof, and the middle portion 44a of the yarn passage contacts the yarn 19. In the embodiment shown in FIG. 13, the yarn passage curves along the running direction of the yarn 19 and, consequently, a part 44b of the inside surface of the yarn passage works as a contacting surface for twisting-in the fuzzy fibers into the main body of the yarn 19. In the two embodiments shown in FIGS. 12 and 13, the area of the contacting surface created by the coiled wire 44 can be easily changed by laterally changing the relative position of either one of the guide bushings 42 or 43 to the other bushing 43 or 42.

The embodiments of the contacting member shown in FIGS. 14, 15 and 16 are a modification of the contacting member shown in FIG. 11. In this embodiment, a plurality of contacting members 24a, 24b, 24c, 24d and 24e are disposed in the yarn passage 13c in such a way that they are disposed at respective positions which are radially symmetric with respect to the central axis of the yarn passage 13c. That is the relative angular disposition between these contacting members 24a and 24b, 24b and 24c, 24c and 24d, 24d and 24e, with respect to the central axis of the yarn passage 13c is represented by 90.degree. as shown in FIG. 16. Each of these contacting members 24a, 24b, 24c, 24d and 24e is provided with a shoe piece 48 and an adjusting bolt 49 engages into the corresponding shoe piece 48. The adjusting bolt 49 is threaded into the feed bushing 13 so as to displace the shoe piece 48 along the transversal direction with respect to the central axis of the yarn passage 13c. Consequently, the transversal position of these contacting members 24a, 24b, 24c, 24d and 24e can be preferably adjusted by turning the corresponding adjusting bolt 49. In this embodiment of the contacting member according to the present invention, to assure free mounting of the yarn package 10 on the feed bushing 13, a plurality of longitudinal grooves 50 are formed on the peripheral surface of the feed bushing 13, in which grooves 50 the heads of the adjusting bolts 49 are positioned. According to our experimental tests, it is preferable that the action of the contacting member 24a disposed at the uppermost position be the strongest, and the actions of the contacting members 24b, 24c, 24d and 24e are gradually weakened from the member 24b to the member 24e. When the yarn 19 passes through the yarn passage 13c, there is a tendency to create small ballooning. Consequently, if the contacting member of the feed bushing 13 works against the yarn 19 from only one transversal direction with respect to the running direction of the yarn 19, there is a posibility of the yarn 19 contacting the contacting member in a jumping condition, i.e., intermittently. However, in this embodiment, since the contacting members 24a, 24b, 24c, 24d and 24e are capable of contacting the yarn 19 in a surrounding condition, a very stable twisting-in action of the contacting member can be created.

In the above-mentioned embodiment of the contacting member, the number of the component elements 24a, 24b . . . . can be changed. Further, component elements 24a, 24b . . . having a round recessed surface may be utilized instead of the component elements 24a, 24b . . . having flat contacting surface shown in FIGS. 14 and 16.

A further modified embodiment of the contacting member according to the present invention is shown in FIGS. 17, 18, 19, 20 and 21. The contacting member is a modification of the contacting member shown in FIGS. 7 and 8. In this embodiment, a supporting ring 51 is rigidly mounted on a bottom inside portion of the feed bushing 13, and a plurality of contacting members 24f, 24g, 24h, 24i, 24j and 24k are superimposed on the supporting ring 51. Apertures 52a, 52b, 52c, 52d, 52e and 52f are respectively formed in the contacting members 24f, 24g, 24h, 24i, 24j and 24k, so as to form the continuous zig-zag yarn passage 13c. The yarn 19 contacts the inwardly projected surfaces of some of the above-mentioned contacting members. In this embodiment the apertures 52a, 52c and 52e are formed eccentrically in the contacting members 24f, 24h and 24j, respectively, and consequently, the zig-zag condition of the yarn passage 13c can be changed by relative angular disposition of these members 24f, 24h and 24j when they are assembled. After assembling these contacting members 24f, 24g, 24h, 24i, 24j and 24k, the relative angular positions thereof are fixed by fastening respective fastening bolts 53. As shown in FIGS. 18, 19 and 20, the contacting surfaces of these contacting members are arranged in such a condition that the phase difference thereof along the transversal plane with respect to the running direction of the yarn 19 in the yarn passage 13c, between each two of the above-mentioned contacting surfaces, is 90.degree.. Consequently, even though the yarn 19 contacts the above-mentioned contacting surfaces, very stable twisting-in action by the contacting members can be expected. In the above-mentioned embodiment, the number of the contacting members, the eccentricity of the apertures and the curvature of the contacting surfaces of these contacting members may be changed so as to attain the purpose of the present invention.

The feed bushing 13 shown in FIGS. 22 and 23 is provided with a contacting member 24 wherein a spiral yarn passage 13c is formed. The lateral cross-section of this spiral yarn passage 13c is gradually enlarged from the upstream position to the downstream position thereof and, consequently, the frictional action of the contacting surface is gradually weakened from upstream position to the downstream position of the yarn passage 13c. The contacting surface formed in the yarn passage 13c passes along a trace 54 which is represented by a dot-dash line shown in FIG. 23, and the yarn 19 receives the frictional action of the contacting surface from all radial directions with respect to the running direction thereof. Therefore, even if the yarn 19 jumps in the yarn passage 13c, very stable twisting-in action by the contacting member 24 is imparted to the yarn 19.

In the above-mentioned explanation concerning the contacting members 24, these contacting members 24 are disposed in the feed bushing 13 at a position just below the capsule 17. However, such contacting member 24 can be satisfactorily disposed at any position along the yarn passage between the capsule 17 and reserve disc 3.

Beside the above-mentioned contacting member 24, an additional means for eliminating the fuzzy fibers can be effectively utilized in the yarn passage between the deflection plate 5 and the yarn guide 21.

Referring to FIGS. 1 and 24, a yarn guide 21 composed of an upper cylindrical portion 56 and a lower conical portion 57 can be utilized as an additional means for eliminating the fuzzy fibers. This yarn guide 21 is held by a supporting bracket 58 which holds the cylindrical portion 56. When the first twisted yarn 19a is carried to the yarn guide 21, the yarn 19a forms a ballooning and, consequently, the yarn 19a contacts the inside contacting surface of the conical portion 57 and, thereafter, passes through the cylindrical portion 56. According to the above-mentioned contact of the yarn 19a with the inside contacting surface of the conical portion 57, the yarn 19a turns about the longitudinal axis thereof while turning through the cylindrical space between the protection pot 7 and the balloon control member 11. Therefore, the fuzzy fibers projected from the main body of the first twisted yarn 19a, which are created by the rubbing contact of the yarn 19a with the reserve disc 3 and the edge 5a of the deflection plate 5, are turned toward the main body of the yarn 19a by the above-mentioned contact of the yarn 19a with the inside contacting surface of the conical portion 57 and, consequently, these fuzzy fibers are twisted-in the main body of the yarn 19a.

Another embodiment of the yarn guide 21 according to the present invention is shown in FIG. 25. In this embodiment, a meandering hollow portion 59 is formed instead of the cylindrical portion 56. This meandering hollow portion 59 provides a pair of contacting surfaces 59a and 59b. Consequently, the yarn 19a is frictionally contacted to these contacting surfaces 59a and 59b, after passing through the conical portion 57, so that a very effective action for eliminating the fuzzy fibers can be created.

In the embodiment of the yarn guide 21 shown in FIGS. 26 and 27, which is a modification of the yarn guide 21 shown in FIG. 24, a plurality of small apertures 60 are formed in the conical portion 57 and the cylindrical portion 56. Each of these small apertures 60 is provided with a space which permits the free escape of some of the fuzzy fibers therethrough. When the yarn 19a, having the fuzzy fibers, passes through the yarn guide 21, as the yarn 19a contacts the inside surface of the conical portion 57, the fuzzy fibers of the yarn 19a enter the small apertures 60. Consequently, since the yarn 19a rotates on its own axis, turns along the circumference of the inside surface of the conical portion 57 and runs upwards, the shorter of the fuzzy fibers are laid down on the main body of the yarn 19a to be twisted into the main body of the yarn 19a. However, the longer of the fuzzy fibers are severed from the main body of the yarn 19a, because of the strong frictional action created by the edge of each of the small apertures 60. Even if the longer of the fuzzy fibers are not severed from the main body of the yarn 19a, they are forced to lay down on the main body of the yarn 19a so that they are twisted into the main body of the yarn 19a.

In the embodiment shown in FIG. 28, which is a modification of the yarn guide 21 shown in FIG. 26, the yarn guide 21 is disposed in a suction box 61 and the suction box 61 is connected to a suction source (not shown) via a suction duct 62. Consequently, even if the condition of the ballooning of the yarn 19a is changed, because of variety of the yarn, twisting condition, etc., the yarn 19a is forced to contact the inside contacting surface of the conical portion 57 of the yarn guide 21 by the suction air via the small apertures 60 and the fuzzy fibers of the yarn 19a are also positively introduced into these apertures 60. Consequently, a more effective twisting-in action of the fuzzy fibers into the main body of the yarn 19a, in comparison with the embodiment shown in FIG. 26, can be created. If long fuzzy fibers are separated from the yarn 19a by the above-mentioned contact of the yarn 19a to the conical portion 57 of the yarn guide 21, these separated fuzzy fibers are carried into the suction box 61 via the apertures 60.

Another embodiment of the yarn guide 21 according to the present invention is shown in FIGS. 29 and 30. In this embodiment, the yarn guide 21 is an assembled body composed of a pair of elements 21a and 21b, each having a spherical recess, and a ball 66 freely disposed in a room 65 formed by the above-mentioned two spherical recesses. The elements 21a and 21b are provided with projections 63 and recesses 64 which receive the projections 63 so as to form the yarn guide 21. The inside spherical surface of the room 65 is finished so as to form a smooth, hard spherical surface. The ball 66 is a hollow body so as to be able to rotate freely in the above-mentioned room 65. When the yarn 19a passes through the yarn guide 21, the yarn 19a firstly contacts the bottom edge of the yarn guide 21 and then is carried upward while contacting the surface of the ball 66. Consequently, the fuzzy fibers of the yarn 19a are twisted-in the main body of the yarn 19a while passing through the yarn guide 21. At the time of starting the twisting operation, the ballooning of the yarn 19a is small, however, the yarn 19a is forced to contact the bottom edge of the yarn guide 21 and the surface of the ball 66 and, consequently, effective twisting-in operation of the fuzzy fibers into the main body of the yarn 19a can be created by the above-mentioned yarn guide 21.

The effect of the twisting-in operation of the fuzzy fibers into the main body of the yarn according to the present invention, wherein the first twisting-in operation is carried out in the yarn passage at the capsule 17 and the second twisting-in operation is carried out when the first twisted yarn 19a passes through the yarn guide disposed above the entry tube of the double twister, is hereinafter explained.

Referring to FIGS. 31 and 32, the yarn tension imparted to the yarn 19 at the position P.sub.1 just upstream from the flyer 20 corresponds to the unwinding yarn tension which is a tension for unwinding the yarn from the yarn package 10. The yarn tension imparted to the yarn 19 at the position P.sub.2 in the entry tube 16 corresponds to the above-mentioned unwinding tension plus a tension created by the turning motion of the flyer 20. The yarn tension imparted to the yarn 19a at the position P.sub.3 which is at the bottom of the spindle 6 corresponds to the above-mentioned yarn tension at the position P.sub.2 plus the tension created by the capsule 17. The yarn tension imparted to the yarn 19a in the yarn passage right after the reserve disc 3 (position P.sub.4) is the tension at the position P.sub.3 plus the tension created by sliding the yarn 19a around the peripheral surface of the reserve disc 3. Finally, the yarn tension imparted to the yarn 19a right after passing the yarn guide 21 (position P.sub.5) corresponds to the yarn tension at the position P.sub.4 plus the tension created by the ballooning between the deflection plate (not shown) and the yarn guide 21. Consequently, the yarn tension which is imparted to the yarn in the passage for imparting the first twist between the capsule 17 and the bottom of the spindle 6, is weaker than the yarn tension, which is imparted to the yarn in the passage for imparting the second twist between the reserve disc 3 and the yarn guide 21. Accordingly, in the passage for imparting the first twist, it is essential not to disturb the effective turning motion of the yarn itself about the longitudinal axis thereof so as to impart the first twists to the yarn 19, if the device of the present invention, that is the contacting member hereinbefore explained is disposed in the above-mentioned yarn passage. In the above-mentioned yarn passage for imparting the first twist, since the yarn is not as compact as the second twisted yarn, the fuzzy fibers can be easily turned to the main body of the yarn and twisted into the main body. However, in tests it has been observed that some of the longer fuzzy fibers still remain in a projected condition from the main body of the first twisted yarn 19a. As hereinbefore explained, because a stronger yarn tension is imparted to the first twisted yarn 19a in the yarn passage for imparting the second twists, a stronger frictional action for eliminating the fuzzy fibers can be applied to the first twisted yarn 19a without disturbing effective turning of the yarn 19a about the longitudinal axis thereof and the effective ballooning of the first twisted yarn 19a. Consequently, a very effective action for eliminating the projection of fuzzy fibers from the main body of the yarn 19a can be created by applying the particular construction to the yarn guide 21 as hereinbefore explained. Based on tests it has been confirmed that the fuzzy fibers twisted into the main body of the second twisted yarn are stably held in. Therefore, it may be understood that the device according to the present invention embodied in the double twister has a function such that the fuzzy fibers projected from the main body of the supplied yarn are forced to be twisted into the main body of the supplied yarn without disturbing the effective turning of the supplied yarn about the longitudinal axis thereof in the yarn passage for imparting the first twist or the second twist, in the double twister.

According to the explanation illustrated hereinbefore, it may be understood that the device of the present invention can be disposed in the yarn passage for imparting the first twist to the yarn 19 or in the yarn passage for imparting the second twist to the first twisted yarn 19a. However, it is preferable that a pair of the devices of the present invention be utilized for the double twister in such a way that a first device, that is a contacting member, is disposed in the yarn passage for imparting the first twist to the yarn 19 while a second device, that is a yarn guide having the particular construction hereinbefore explained, is utilized as a terminal of the yarn passage for imparting the second twist to the first twisted yarn 19a.

In our experimental tests, it was confirmed that, in the double twister shown in FIG. 1, if the so-called unwinding twist is imparted to the yarn 19 in the yarn passage between the flyer 20 and the guide bush 22 rigidly mounted on the entry tube 16, the effective twisting-- in operation of fuzzy fibers into the main body of the yarn 19 in the yarn passage downstream of the contacting point of the lower portion of the capsule 17 with the small cylindrical member 15 is disturbed. However, since the tension means comprising the tensor container 14, small cylinder 15, capsule 17 and the small entry tube 16 is turned together with the flyer 20, the above-mentioned unwinding twist is imparted to the yarn right after the yarn passes through the contacting point of the lower portion of the capsule 17 with the small cylinder 15. Consequently, the above-mentioned possible disturbance due to the unwinding twist can be effectively eliminated when the supplied yarn 19 contacts the entrance edge of the guide bush 22. Consequently, even though the contacting member 24 works to twist in the above-mentioned fuzzy fibers into the main body of the yarn 19, it is preferable to prevent such easy creation of the fuzzy fibers. The embodiment shown in FIG. 33, is provided with a particular construction for preventing the above-mentioned easy creation of the fuzzy fibers. That is, in the double twister shown in FIG. 33, the entry tube 16 and a tension mechanism provided with the tenser container 14 and the capsule 17 are capable to turning with the flyer 20. In the following explanation of the double twister wherein the device of the present invention is applied, the component elements having a similar function to the component elements of the double twister shown in FIG. 1 are represented by the identical reference numerals, respectively, and the explanation thereof is omitted.

Referring to FIGS. 33, 34 and 35, a sliding disc 70 is coaxially mounted on the upper portion 13a of the feed bushing 13 by means of thread engagement. The tenser container 14 is rotatably mounted in the upper portion 13a of the feed bushing 13 by way of a needle bearing 71, the upper cylindrical inside wall 14c is provided with a screw thread and an aperture 14d is formed in the outer wall thereof. As in the embodiment shown in FIG. 1, the small cylindrical member 15, made of a material having low frictional resistance such as an aluminum ceramic material, is disposed at the bottom portion of the tenser container 14. A cylindrical body 72 is secured to a middle portion of the tenser container 14 by thread engagement and an upper cylindrical body 73 is disposed in the tenser container 14 at a position just below the level of the body 72. The capsule 17 is sandwiched by the upper cylindrical body 72 and the small cylindrical member 15. The capsule 17 is provided with an expansion spring (not shown) disposed therein and the capsule 17 has a construction such that it is capable of longitudinaly expanding. Consequently, the upper and lower ends of the capsule 17 are urged to the upper cylindrical body 73 and the small cylindrical member 15, respectively. As a result, the yarn 19 is stretched when it is pulled from the contacting points between the lower end of the capsule 17 and the small cylindrical member 15. The tension of the yarn 19 can be changed easily by changing the capsule 17 so as to change the expansion force thereof due to the expansion spring disposed therein. If it is required to adjust the above-mentioned yarn tension a little, it is sufficient to turn the entry tube 16 so that the cylindrical body 72 is displaced upward or downward along the longitudinal axis of the tenser container 14 so that the upper cylindrical body 73 is displaced upward or downward. A flyer ring 74 is rigidly mounted on the tenser container 14 at an upper portion thereof by thread engagement as shown in FIG. 35. A base portion 75 of the flyer 20 is rigidly mounted on the entry tube 16 in such a condition that the base portion 75 contacts the flyer ring 74. Fixing grooves 75a are formed on the outer surface of the base portion 75 and a step portion 75b is formed at the upper end portion of the base portion 75 of the flyer 20.

A flyer guide 20b of a resilient metallic material is detachably inserted into the grooves 75a as shown in FIG. 34, and a pair of yarn guides 20a is formed at the free ends of flyer guide 20b. Accordingly, the entry tube 16 and the tension mechanism, comprising the tenser container 14 and the capsule 17, etc., are capable of turning together with the flyer 20 and the unwinding twist is imparted to the yarn 19 at a position below the capsule 17. In the above-mentioned embodiment, a weight 76 is detachably mounted on the step portion 75b of the base portion 75 of the flyer 20. Therefore, the bottom surface of the flyer ring 74 is frictionally contacted to the upper surface of the sliding disc 70 so that free turning of the assembled body, composed of the flyer 20 and the entry tube 16, and the tension mechanism, comprising the tenser container 14 and the capsule 17, can be prevented. If it is required to increase the driving speed of the spindle 6, it is preferable to use a weight 76 having increased weight. An expansion spring 77 is mounted on the entry tube 16 at a position between the base portion 75 of the flyer 20 and the cylindrical body 72 and, consequently, the disposition of the cylindrical body 72 relative to the entry tube 16 can be stably maintained. The contacting member 24 inserted into the feed bushing 13 works to twist-in the fuzzy fibers into the main body of the yarn 19 in a manner similar to the embodiment shown in FIG. 1.

The mechanism shown in FIGS. 36 and 37 is a modified device for adjusting the yarn tension in the tension mechanism which is applicable to the double twister shown in FIG. 33. In this tension mechanism, the cylindrical body 72 is provided with a plurality of engaging grooves 80 formed with an identical interval therebetween at the bottom portion of the cylindrical body 72, and the tenser container 14 is provided with a pin 81 projected inward from the inside wall at a position where the pin 81 is capable of being inserted into any one of the above-mentioned grooves 80. The engaging grooves 80 are provided with lengths which are different from each other. Therefore, the pushing force created by the spring 77 can be easily changed by changing the groove 80 which receives the pin 81.

The double twister shown in FIG. 38 is a modification of the double twister shown in FIG. 33. In this double twister, the feed bushing 13 is further provided with an oiling function in addition to the function of twisting-in the fuzzy fibers into the main body of the yarn 19. Since the main mechanism of this double twister is similar to the double twister shown in FIG. 33, identical reference numerals are used for elements which are similar to the elements of the double twister shown in FIG. 33, and the explanation concerning these elements is omitted. Consequently, the following explanation is directed toward the construction and function of the feed bushing 13.

Referring to FIGS. 38, 39 and 40, an oiling bath 82 is detachably disposed in the feed bushing 13, and the oiling bath 82 is composed of an outside bath 83 made of a transparent material and an inside bath 84 disposed in the outside bath 83. The outside bath 83 is connected to the inside bath 84 via a plurality of connecting apertures 85 formed at a bottom wall portion of the inside bath 84. A meandering yarn guide member 86 made of a porous material is disposed in the inside bath 84 so as to form a yarn passage. The function of this meandering yarn guide member 86 is quite similar to the contacting member 24 shown in FIG. 22, except that oil which moves into the yarn passage through the porous material of the yarn guide member 86 works is additionally promote the twisting-in of the fuzzy fibers into the main body of the yarn 19 when the yarn 19 contacts the inside surfaces 86a of the meandering yarn guide member 86. The outside bath 83 is provided with a plurality of inlet aperture 87 for supplying oil thereinto. Since the yarn surface of the yarn 19 is provided with oil, the creation of fuzzy fibers, when the yarn passes over the peripheral surface of the reserve disc 3 and the edge 5a of the deflection plate 5, is effectively controlled. Creation of static electricity when the yarn 19 is rubbed is also effectively prevented by the above-mentioned oiling.

When it is required to change the oiling device in the above-mentioned double twister, the tension mechanism comprising the tenser container 14 and capsule 17, the entry tube 16 and flyers are taken from the feed bushing 13, and then the oiling device can be exchanged.

In the oiling device shown in FIGS. 41, 42 and 43, several modifications are applied. That is, in the oiling device shown in FIG. 41, an oil supply pipe 89 is provided instead of the aperture 87. In the oiling device shown in FIG. 42, a cover 90 is disposed on the opened top of the oiling device so that the supplying of oil 88 can be easily carried out. In the oiling device shown in FIG. 43; the inside oil bath 84 in the embodiment shown in FIG. 41 is omitted; the yarn guide member 86 is made of a solid material such as a plastic or iron; a plurality of small apertures 91 are formed in the wall of the yarn guide member 86, and; a piece of fabric 92 (guaze) or sponge rubber is inserted into each aperture 91 in such a condition that a bottom portion of the fabric or sponge rubber 92 is immersed into the oil 88 of the oil bath 83. As mentioned above, the oiling device applied to the feed bushing 13 has a simple construction and can be made compact, and consequently, such oiling device provides a very practical advantage to the double twister.

Many different modifications can be applied to the double twister according to the present invention in the spirit of the present invention. It is also noted that further modification of the device embodied in the double twister can be effected, such as:

(a) any material can be utilized for making the device of the present invention if the above-mentioned function for twisting-in the fuzzy fibers into the main body of the supplied yarn is realized;

(b) any surface treatment may be applied for the contacting surface of the device according to the invention, if the above-mentioned function for twisting-in the fuzzy fibers into the main body of the supplied yarn is realized;

(c) the contacting member shown in FIGS. 4 through 23 can be utilized instead of the conventional snail wire disposed above the entry tube of the double twister;

(d) the contacting member shown in FIGS. 4 through 23 can be utilized to attain the purpose of the present invention in such a condition that the contacting member is disposed along the yarn passage at a position adjacently upstream or downstream of the conventional snail wire disposed above the entry tube of the conventional double twister.