Title of Invention

A HEATING DEVICE FOR HEATING AN ADVANCING SYNTHETIC FILAMENT

Abstract

The present invention relates to provides a heating device for heating an advancing synthetic filament yam (8), the device comprising an elongate groove (4) and substantially parallel side walls (6,7), an elongate carrier (1) forming a structural unit together with yam guides (2,3), the yam guides (2,3) advancing the yam in the groove (4) along a zigzag path, and the structural unit resting against the side walls (6,7) of the groove, characterized in that the carrier (1) is a solid, highly heat conductive preferably metallic body, which is mountable on the bottom of the groove (4), and on which the yam guides (2,3) comprising pins extending upwards in the groove (4) are mounted PRICE: THIRTY RUPEES

Full Text

The present invention relates to a heating device for heating an advancing synthetic filament yarn. In particular for crisping synthetic filament yarns in a false twist crimping r.achine, heating devices are provided for advancing a yarn therethrough. The yarn advances in a heated groove. A heating device may conprise several grooves, each of which accommodates one yarn. Known from EP 0 4 12 429 Bl is a heating device with a heated groove, in which the yarn is guided along a zigzag line. The zigzag line is defined by several yarn guides, each turning point of the line acconaodating one yarn guide. The known heaters are operated at a temperature, which is substantially higher than 300=0. At these temperatures, a portion cf the organic compounds evaporates, whereas an organic compounds deposit on the yarn guides. These deposits occur, since the yarn cor.es into contact with the surface of each yarn guide. These deposits increase in the course of the time. An increase in the deposits has the consequence that the yarn is no longer urged to follow a predetermined path. However, the yarn path in the heater influences the quality of the yarn. Accordingly, the quality of the yarn can be influenced by the deposits. The constructional design of known heaters makes a cleaning of the individual yarn guides relatively expensive. In addition, the deposits are very hard as a result of the temperatures in the heater, and they are only difficult to remove from the yarn guides. It is therefore the object of the present invention to further develop the known heater, so as to simplify the cleaning of the yarn guides. A further object of the invention is to reduce the production requirement and, thus, likewise the cost of manufacture of a heating device. This object is achieved by a heating device having the characteristic features of claim 1. Advantageous further developments are subject matter of the dependent claims. The heating device of the present invention is characterized in that the yarn guides are designed and constructed as pins, and that they are attached to a solid, highly heat-conductive carrier. As a result of the high heat conductivity, an insulating effect is absent during the heating of the groove. The solid construction of the carrier imparts to the structural unit an inherent stability, which turns out to be advantageous especially during an exchange and a subsequent cleaning process. The structural unit is easy remove from the groove of the heating device. After removing the carrier with the yarn guides, same can be cleaned without a problem, since the yarn guides are easily accessible from all sides. Besides the eased possibility of cleaning the yarn guides, no expensive measures are needed to arrange the yarn guides in the channel. As described in claim 2, the yarn guides are arranged on the carrier, so that the yarn is advanced along a zigzag line. Preferably, the spacings between the yarn guides are made equal. The clamping force between the structural unit and the groove walls is absorbed by the yarn guides, As a result, the contact surface is considerably reduced between the structural unit and the side walls of the groove. The arrangement of two successive yarn guides on one side has the advantage that the looping angle on each yarn guide is reduced by 50%. The embodiment of the heating device of claim 3 is characterized in that the yarn guides are attached to the carrier such that they are supported indirectly on the opposite side wall of the groove. To this end, the yarn guide may be followed by a correspondingly curved section, which may be bent, for example, into an L-shape, U-shape, or T-shape. The yarn guides are arranged at least on one carrier, which is deformed in zigzag-shape and supports itself on the opposite side wall. This configuration permits each yarn guide to be pushed by the carrier against the side wall of the groove, the yarn guide assuming thereby a stable position. The force which the carrier exerts on the yarn guides may be adjusted by corresponding fits or resilient characteristics of the carrier. The clamping of the yarn guides ought to be so strong as to prevent the yarn guides from being moved out of their position by the yarn advancing therealong. Preferably, identical yarn guides are arranged on both sides of the carrier. A further possibility of fitting and securing the yarn guides with the carrier in the groove is described in claim 4, The v;idth of the carrier and the width of a yarn guide correspond approximately to the width of the groove. For example, it is possible to mount each yarn guide only on a carrier associated to it. The carrier with the yarn guides are then fitted into the groove. This requires that the position of the yarn guides relative to each other in the longitudinal direction be exactly readjusted each tir.e. This requirement is avoided in the embodiments of claims 7 and 8. In both cases, a structural unit is initially produced, vhich consists of an elongate strip and the yarn guides attached thereto. Preferably, the strip has plane parallel lateral surfaces, to which the yarn guides can be attached, for example, by welding. The yarn guides are arranged on both sides of the strip offset from each other in the longitudinal direction. Upon inserting the strip with the yarn guides into the groove, the spring elastic strip is clamped in zigzag shape in the one embodiment, since rhe overall width of two adjacent yarn guides and the strip is at least wider than the groove, namely at least by the width of the strip. As a result, the strip is deflected to a zigzag line, and due to its elasticity, it pushes the yarn guides of the one and the other side against the associated groove walls. If the carrier with the yarn guides is arranged in the groove, the carrier will be forced to follow a zigzag line. In so doing, the yarn guides are pushed with one of their sides against a side wall of the groove. The zigzag path of the yarn is determined by the tolerances of the groove, the yarn guides and the carrier. As a result of the arrangement of the yarn guide, the yarn is safely supported relative to the groove bottom, v;ithout it being possible that rhe yarn is clamped at the junctions between each yarn guide and the carrier. in the otiher embodiment, no use is made of a spring-elastic strip, or the spring elasticity has no effect. This embodiment is advantageous, especially when a loss in the spring effect is to be expected because of the high temperatures. In this instance, one yarn guide and the width of the strip fill the entire width of the groove. The two aforesaid embodiments have the advantage that the structural units consisting of a strip and yarn guides may be pulled out from the groove, either from the upper side thereof or, however, in longitudinal direction. It is not: necessary to readjust the carrier and the yarn guides after cleaning. Upon the removal of the structural unit by pulling it out lengthwise, the groove is likewise cleaned, so that a substitute structural unit may again be inserted immediately. In accordance with a further thought, it is proposed to provide two carriers. These carriers are arranged in the groove so as to overlie one another. Each carrier accommodates only yarn guides, which rest against the same side wall of the groove. The individual carriers may be releasably joined to each other, so as to form one structural unit. This proposed layout for the arrangement of the carriers and yarn guides has the advantage that it is possible to exchange individual carriers with the yarn guides, for example, when same are worn. Preferably, the flexible carrier has a zigzag configuration. This zigzag configuration has the advantage that the carrier is supported on several points of the side wall of the groove. The embodiment of claim 9 has the advantage that the clamping force is absorbed exclusively by the carrier, or adjusted by the fit that is selected between the carrier and the groove. Furthermore, this arrangement precludes a contact between the yarn guides and the side wall, wkich results in an advantageous, low surface temperature of the yarn guides. According to claim lO, the carrier is held in the groove bottom both in force-locking and in form-locking engagement. Suitably, the carrier has a rectangular cross section. This design of the carrier has the advantage that it allows to sinplify the connection of the carrier with the individual yarn guides. Further, the carrier is supported on the side vail along a line. The carrier having a rectangular cross section nay be a sheet restal strip, which has spring-elastic characteristics. However, the spring-elastic characteristics of the carrier are independent of the cross section and the configuration of the carrier. Preferably, the carrier and the yarn guides consist of a metallic material. This has the advantage that the yarn guides can be joined to the carrier inseparably, for example, by welding or soldering. In the case of carriers having a great inherent stability, it is also possible to join yarn guides of a nontnetallic material in a simple manner by force-locking or fornlocking engagements with the carrier. The ensure that the wear resistance of the yarn guides is adequate, the yarn guides may be provided with a coating of a hard material. It is not necessary that the carrier extend over the entire length of the heating device. The zigzag course of the yarn may be realized likewise, in that several carriers with yarn guides are arranged, one following the other directly or indirectly. The arrangement of several longitudinal segments, one following the other, allows to form several heating zones with differently spaced yarn guides. Accordingly, the present invention provides a heating device for heating an advancing synthetic filament yam, the device comprising an elongate groove and substantially parallel side walls, an elongate carrier forming a structural unit together with yam guides, the yam guides advancing the yam in the groove along a zigzag path, and the stmctural unit resting against the side walls of the groove, characterized in that the carrier is a solid, highly heat conductive preferably metallic body, which is mountable on the bottom of the groove, and on which the yam guides comprising pins extending upwards in the groove are mounted. Further advantages and features of the heating device in accordance with the invention are described in more detail with reference to the accompanying drawings, in which: Figure 1.1 is a top view of a structural unit with a carrier and yam guides; Figure 1.2 is a top view of a stmctural unit with a flexible carrier and yam guides; Figure 1.3 is a top view of a structural unit with a carrier and yarn guides; Figure 2 is a cross sectional view of a structural unit with carrier and yarn guides; Figure 3.1 is a schematic top view cf a heating device with carrier and yarn guides of Figure 1.2 Figure 3.2 is a schematic top view of a heating device with yarn guides and carrier; Figure 3.3 is a schematic top view of a heating device with yarn guides and carrier of Figure 1.1; Figure 4.1 is a front view of a heating device; Figure 4.2 is a front view of a heating device; Figure 5 is a front view of a heating device with carrier and yarn guides; Figure 6 is a top viev; cf the erbodiment of Figure 5; Figure 7 is a side view of a structural unit with carrier and yarn guides; and Figure S is a top view of a heating device with a heated carrier divided into two longitudinal segments. Shown in Figures l.l, 1.2, and 1.3 are top views of different embodiments of a structural unit, which consist each of a carrier 1 and yarn guides 2 and 3 respectively. The yarn guides 2 and 3 have a circular cross section. Other cross sections are also possible. In particular, cross sections may be selected, v;hich direct to the yarn a contact surface with a large radius, as shown by way of example both in Figure 1.3 and in Figure 5, For carrier l, as shown in Figures 1.1 and 1.3, a flat steel or a strip steel may be used, which has a width B. The width B and the width of the groove are approximately the same or adapted such that the structural unit is held in the groove in force-locking engagement. In this instance, the clamping forces are selected such tnat the yarn guides remain unchanged in their position during the operation. The carriers are made solid, i.e., they are bar-shaped with a square, rectangular, circular, semicircular, or polygonal cross section. The yarn guides 2 and 3 are each mounted on the surface of carrier 1 by way of a press fit, as shown in Figure 2, or by velding or. soldering. In Figure l.l, the yarn guides 2 and 3 respectively are constructed as pins, which are arranged on the surface of carrier 1, so that they come to lie, alternately or in pairs, on the one and on the opposite longitudinal side of carrier l. Thus, the spacing between the sides of yarn guides 2 and 3 facing away from each other is approximately equal to the width B, so as to pemit the yarn guides 2 and 3 to be supported each on side walls 6 and 7 of groove 4 (note. Figure 4.1). Each of the yarn guides 2 and 3 has a diameter which is larger than half the width E, thereby realizing a zigzag path of the yarn. As shown in Figure 1.2, a carrier i having the forir. of a lengthwise extending strip with two parallel sides, accommodates on both sides yarn guides 2 and 3 respectively. The carrier 1 may be a round wire or a rectangular strip or a strip with parallel sides. The yarn guides 2, 3 are attached to the carrier in equally spaced-apart relationship. The yarn guides 2, 3 may be joined to carrier 1 by welding, soldering, or the like. The yarn guides shown in Figure 1.2 have the same diameter. The width B, which is composed of the diameter of yarn guide 2 or 3 and the width of carrier 1, is somewhat larger than the width of groove 4, which is formed in a heating device 5. Likewise shown in Figure 1.3 is an arrangement, in which the yarn guides 2 and 3 respectively are located on the surface of carrier 1. In this embodiment, the yarn guide 2 and 3 have each on their end facing the carrier a diameter on the order of width B, as shown in Figure 2. At about two thirds of its length, the yarn guide has an almOst elliptically shaped cross section with a width that is greater than half the width B, The yarn 8 contacts the yarn guide at a large radius, so that it has a great length of contact with a small angle of looping. The L-shape of the yarn guide prevents the yarn 8 from coming into contact with carrier l and, thus, avoids an excessive heating. For its mounting, the yarn guide 2 or 3 is pressed with a pin 15 into a bore 16 of carrier l. To facilitate the threading of the yarn, the free end of yarn guide 2 or 3 is provided with a bevel 14. Figure 3.1 illustrates a heating device 5 with an elongate, U-shaped groove. Inserted into this groove is carrier 1 accommodating yarn guides 2, 3 of Figure 1.2. When inserting carrier 1 with yarn guides 2, 3, the carrier l is forced to assume the direction of a zigzag line. The individual yarn guides 2, 3 rest against a side wall 6 and 7 respectively of the groove 4. The carrier 1 is supported alternatingly on side wall 7 and 6 respectively. Prerequisite therefor is that the strip which forms the carrier, is elastic and remains elastic, even when heated to more than 400C. Shown in Figure 3.2 is the top view of a heating device, which also illustrates the path of a yarn 8. Figure 3.3 illustrates a heating device 5 with an elongate, U-shaped groove, into which a carrier 1 of Figure 1.1 is inserted so as to extend on the bottom thereof. A pair of yarn guides 2 and 3 is arranged alternately on the one side and on the opposite side of the carrier- This arrangement allows to reduce the looping angle on each yarn guide by 50%. Thus, the yarn is subjected to less friction, which aqain manifests itself in a lesser change in yarn tension and, thus, in a higher yarn quality. Figure 4.1 is a vertical sectional view of this embodiment. The heating device is also an elongate rail as shown in a shorter length, though, in Figure 3.2. Arranged in the rail is a longitudinal groove with two parallel side vails 6, 7. Clamped into the longitudinal groove is a structural unit, which consist of a strip-shaped carrier l with yarn guides 2 and 3 attached to the sides thereof. The yarn guides are arranged on both sides, offset and equally spaced apart from one another. Upon clamping the structural unit into the groove, the carrier 1 is deformed to a winding position, so that the structural unit is fitted therein under the action of elastic clamping forces. The heating device is heated by an electric resistance heating element 9 that is constructed in form of a rod. This rod is inserted into a bore, which is provided lengthwise in the base plate of the heating device. It should be remarked that the cross sectional view of Figure 4.1 applies likewise to the description of Figure 3.1. The yarn guides 2, 3 are secured in the groove by caps 10. These caps lo are C-shaped. They embrace the upper, longitudinal edge of each side of the groove, and engage into small, longitudinal channels, which are provided in the side walls 6, 7 of the groove sides on both sides of the upper, longitudinal edges. This description applies also to Figures 1.2 and 3.1. Figure 4.2 is a vertical sectional view of a heating device with a plate-shaped carrier 1. The yarn guides 2 and 3 are arranged each on carrier 1, as shown in Figure 1.1, the spacing between the sides of the yarn guides 2 and 3 that face away from each other being smaller than the width B. As a result, there is no contact between the side walls 6 and 7 of groove 4 and the yarn guides 2 and 3. The yarn guides 2 and 3 can no longer be heated by thermal conduction, so that a lover surface temperature exists on each of yarn guides 2 and 3. In this embodiment, the side walls 6 and 7 of groove 4 are provided with an undercut 11 and 12 respectively, into which the carrier 1 engages, so that the structural unit is held in groove 4 in forra-locking engagement. The embodiment of Figures 5 and 6 comprises again the elongate heater, which contains a longitudinal groove with parallel side walls 7, 6. This longitudinal groove accommodates a structural unit. The structural unit consists again of a lengthwise extending carrier 1 with yarns guides 2, 3 mounted on its sides. In the longitudinal direction, the yarn guides 2, 3 are arranged equally spaced apart, but offset from one another on both sides of the strip-shaped carrier. The strip-shaped carrier is made in zigzag form, with a yarn guide being mounted in each bend. The diameter of a yarn guide and the width of carrier 1 correspond exactly to the width of the groove. This allows to fit the structural unit into the longitudinal groove without a lateral clearance. The structural unit is again held in the groove by caps lo. Their description with reference to Figure 4.1 is herewith incorporated. At its end (note Figure 6), the carrier is provided with holes 21. These holes can receive a suitable tool, which permits the carrier to be removed by pulling it out lengthwise from the groove. As a result, the groove is also cleaned. Immediately thereafter, a new carrier with the yarn guides attached thereto is introduced into the groove, so that for a cleaning the operation of the heating device is not interrupted as result of cooling. The carrier with the yarn guide element that is removed from the heating device can now be cleaned in a cleaning bath. It should be remarked that in this embodiment, two heating elements 9 are arranged in the bottom of the heating rail, thus achieving a more uniform heating over the width of the heater. Shown in Figure 6 are two yarn guides 19 and 2 0 with a substantially semicircular cross section. They contact the yarn with a large radius, so as to realize a great length of contact results at a small angle of looping. Other cross sectional shapes, such as, for example, ellipses are also possible. Such yarn guides substitute the circular pins, or alternate with same. Figure 7 is a side view of a structural unit with a solid carrier and yarn guides, as has been described above with reference to Figure l.1 or Figure 1.3. In this embodiment, a bottom spacer 13 is arranged between two adjacent yarn guides 2, 3, so as to prevent the yarn from contacting che carrier. The high surface temperarure of the carrier, which lies on the groove bottom would be liable to overheat the yarn. Shown in Figure 8 is a heating device with an elongate, U-shaped groove, which accommodates a carrier that is divided into two longitudinal segments 17 and 18. The yarn guides 2 and 3 are differently spaced from each other over the length, so that the heating device has two zones which are used advantageously for purposes of optimizing the temperature and the yarn quality. WE CLAIM: 1. A heating device for heating an advancing synthetic filament yam (8), the device comprising an elongate groove (4) and substantially parallel side walls (6, 7), an elongate carrier (1) forming a structural unit together with yam guides (2, 3), the yam guides (2, 3) advancing the yam in the groove (4) along a zigzag path, and the stmctural unit resting against the side walls (6, 7) of the groove, characterized in that the carrier (1) is a solid, highly heat conductive preferably metallic body, which is mountable on the bottom of the groove (4), and on which the yam guides (2, 3) comprising pins extending upwards in the groove (4) are mounted. 2. The heating device as claimed in claim 1, wherein alternating in the longitudinal direction, one or two pins (2) are attached on the one side, and one or two pins (3) on the other side, and that the overall width of the stmctural unit consisting of pins (2, 3) and carrier (1) is equally wide as or wider than the width of the groove, in the case of the latter the carrier being elastically deformable, and that the pins rest against the groove wall. 3. The heating device as claimed in claim 1, wherein the carrier is deformed to a zigzag line in a plane parallel to the groove bottom, so that it forms bulges offset from one another, that in each bulge one or two pins (2, 3) are mounted, and that the pins are laterally supported on the groove walls. 4. The heating device as claimed in claim 2, wherein the pins (2, 3) are unilaterally arranged on the side of the carrier (1), which rests against the opposite side wall (7 or 6). 5. The heating device as claimed in claim 3, wherein a first and a second carrier are provided, that the carriers are arranged on top of each other, and that the yam guides that rest against the same side wall, are arranged unilaterally on one of the two carriers, and that the width (B) of the carrier (1) and the width of one yarn guide (2 or 3) correspond to the width of the groove (4). 6. The heating device as claimed m claim 5, wherein the carriers are designed and constructed as zigzag strips, and that the pins are mounted in the cusps of the one side, and that the cusps of the other side rest against the groove wall facing same. 7. The heating device as claimed in claim 3, wherein the can'ier is designed and constructed as a zigzag strip, that the pins are mounted in the cusps of both sides, and that the pins rest against opposite side walls (6, 7) under the action of the spring elasticity of the carrier. B. The heating device as claimed in claim 3, wherein the carrier is designed and constructed as a zigzag strip, that one of the pins is mounted respectively one the inner side of the cusps, and tliat in the cusp the width (5) of the carrier (1) and the width of the pin (2, 3) correspond to the width of the groove (4). ). The heating device as claimed in any one of the claims 1-8, wherein the carrier fills the width of the groove, and that the yam guides are attached to its upper side. !(), The heating device as claimed in any one of the claims 1-9, wherein the groove contains in the region of its bottom a guide channel in both or one longitudinal walls, into which the carrier engages in full or with a longitudinal edge. 11. The heating device as claimed in any one of the claims 1-10, wherein the carrier has a rectangular cross section. 12. The heating device as claimed in any one of the claims 6 or 7, wherein the carner consists of a spring elastic material. 13. The heating device as claimed m any one of the claims 1-12, wherein tlie yam guides consist of a metallic material. 14. The heating device as claimed in claim 13, wherein the yam guides are provided with a hard material coating at least in the guiding region of the yam. 15. The heating device as claimed in any one of the claims 1-14, wherein the yam guides (2, 3) are equidistant from each other. 16. The heating device as claimed in any one of the claims 1-14, wherein the carrier is divided into longitudinal segments (17, 18), and that the yam guides (2, 3) of one longitudinal segment are equidistant from each other. 17. llie heating device as claimed in claim 16, wherein the longitudinal segments (17, 18) are of the same length. 18. A heating device for heating an advancing synthetic filament yam substantially as herein described with reference to the accompanying drawings.

Documents:

1237-mas-1995 abstract.jpg

1237-mas-1995 abstract.pdf

1237-mas-1995 claims.pdf

1237-mas-1995 correspondence -others.pdf

1237-mas-1995 correspondence -po.pdf

1237-mas-1995 description (complete).pdf

1237-mas-1995 drawings.pdf

1237-mas-1995 form-1.pdf

1237-mas-1995 form-26.pdf

1237-mas-1995 form-4.pdf

1237-mas-1995 form-9.pdf

1237-mas-1995 others.pdf