JP2006265791A - Method for detecting fuzz and fuzz detector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fuzz detector which little interferes yarn-guiding works, can detect fuzzes without separating the fuzzes from the main body of the yarn by a centrifugal force, and does further not lower detection accuracy due to the smoke of an oil or the like. <P>SOLUTION: This method for detecting the fuzzes is characterized by processing cut filaments (fuzzes) formed on a traveling multi-filament yarn Y into pile-like fuzzes S, introducing the multi-filament yarn Y into a slit-like gap G between a pair of guides 11 between which the gap G is formed, converting passage resistance added to a pair of the guides 11 on the passage of the introduced multi-filament yarn Y through the gap G with a passage resistance detector 13 comprising a load detector, strain detector or vibration detector into a force, strain or vibrations (frequency and/or amplitude) to determine the passage resistance, and judging the passage of the fuzzed multifilament with an abnormality-judging means 15, when the determined value satisfies a value preliminarily set to judge the passage of the fuzzes. And the detector 1. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a fluff detection method and apparatus capable of accurately detecting, on-line, yarn ball-like fluff (slab) generated on a yarn traveling in a yarn making process.

  In recent years, in the manufacturing process of synthetic fibers such as polyester fibers and polyamide fibers, especially in the manufacturing process of fibers for industrial materials such as tire cords, seat belts and airbags, the spun yarn is drawn directly without being wound once. Direct spinning and drawing methods are actively performed.

  In such a spinning process, on the one hand, the spinning speed is increased to 2000 m / min or more, and on the other hand, a severe drawing heat treatment for producing high quality yarns such as high strength, high toughness and high durability. Is required. For this reason, it is in a situation where single fiber breakage (hereinafter referred to as “fluff”) is likely to occur due to severe and high-speed drawing heat treatment.

  Generation | occurrence | production of such a fluff causes not only the deterioration of a production process tone but also a problem in the quality side as a fiber for industrial materials. Further, when such a yarn having fluff is subjected to a high-order processing step for finishing a final product such as a tire cord, a seat belt, and an air bag, a problem often arises in its handling property.

  Therefore, in order to prevent the yarn having the fluff from being used in the subsequent processes of the yarn production process, the fluff generated in the yarn production process is directly monitored online to remove the fluffed product at the same time. It is necessary to take measures to quickly reduce the occurrence. From this point of view, if a fluff occurs, a fluff detector is required to immediately monitor the occurrence of fluff online. As such a conventional fluff detector, in the synthetic fiber manufacturing field, a non-contact type fluff sensor using mainly an electrostatic capacitance sensor and an optical sensor has been used.

  However, in such a conventional non-contact type fluff sensor, there is little problem in measurement reproducibility and accuracy when the running speed of the yarn is slow, but the running speed of the yarn is, for example, 2000 m / min or more. If the speed is increased, there will be a problem in the measurement accuracy. Further, when trying to increase the measurement accuracy, the sensitivity adjustment becomes difficult, and the mounting position and use environment are limited (cannot be used in a place where there is a lot of dust or oily smoke). Furthermore, there is a problem that it is difficult to always keep the measurement conditions constant due to the influence of dirt due to long-term use, and it is difficult to manage after installation, and therefore it is not fully utilized.

  Therefore, instead of the non-contact type fluff detector as described above, as proposed in Japanese Patent Publication No. 52-18819, Japanese Patent Application Laid-Open No. 2000-199167, Japanese Patent Publication No. 62-261, etc. It has been considered to use a contact-type fluff detector that detects fluff by directly contacting fluff generated on a strip with a fluff detection probe.

  For example, the contact type fluff detector proposed in Japanese Patent Publication No. 52-18819 is effective in reliably detecting fluff generated on a yarn traveling at a low speed of about several meters per second. However, this fuzz detector can detect fuzz well when the fuzz is not so loose from the yarn body or when the fluff release position is in the direction opposite to the installation direction of the fuzz detection needle. There is a problem that can not be. In particular, in a yarn traveling at high speed, this problem is serious because the yarn passes through the installation portion of the fluff detection needle within a moment.

  Therefore, in place of such a contact type fluff detector, Japanese Patent Publication No. 52-18819 and Japanese Patent Laid-Open No. 2000-199167 propose a contact type fluff detector that can detect fluff even in a high-speed region. ing. These technologies utilize the centrifugal force generated when a high-speed running yarn changes its running direction, and the fluff is released from the yarn body by the centrifugal force, and the released fluff is removed from the fluff detection end. It is a technology that detects the impact force generated at the time of collision. According to this technique, the direction of the fluff to be released becomes the direction of action of the centrifugal force, and the fluff detection end can be provided in this portion. Therefore, the problem of the technique described in Japanese Patent Publication No. 62-261 is a problem. Can be resolved.

  However, in the above technique, it is required to combine with a device for generating a centrifugal force such as a roller for changing the running direction of the yarn in order to obtain a centrifugal force for releasing the fluff from the yarn body. If it does so, a detector will be installed in the very vicinity of the roller rotating at high temperature and high speed, but it is not realistic considering the use environment. Furthermore, these technologies essentially require changing the running direction of the yarn to obtain a centrifugal force, so that it is difficult to detect fluff well for a straight running yarn. Needless to say, it contains the fundamental problem.

Japanese Patent Publication No. 52-18819 Japanese Patent Publication No.62-261 JP 2000-199167 A

  An object of the present invention is to solve various problems of the conventional technology described above. In other words, it can be used on-line for high-speed drawing where the running multifilament yarn swings greatly, and is not limited by the installation location. It is an object of the present invention to provide a fluff detector that does not cause degradation.

  Here, as an invention according to claim 1, which is a fluff detection method for solving the above-mentioned problem, “a cut filament (fuzz) generated in a traveling multifilament yarn is formed into a yarn ball shape and formed into a slit shape. A multifilament yarn is introduced into the gap between a pair of guides that form a gap, and the passing resistance received from the pair of guides when the introduced multifilament yarn passes through the gap is force, dynamic strain, or vibration (frequency And / or amplitude) and quantified, and when the quantified value satisfies a value set in advance as a value that can be regarded as the passage of the fluff, it is determined that the multifilament yarn having the fluff has passed ” Is provided.

  In this case, the invention is characterized in that, as in the invention according to claim 2, the yarn ball-like filaments are formed by entanglement of the filaments constituting the multifilament yarn. It is preferable to use the fluff detection method described in 1. In addition, the fluff detection method according to claim 2 is preferably used after the entanglement process in the spinning direct drawing step as in the invention according to claim 3.

  And as for the said invention, the invention related to Claim 4 WHEREIN: The said yarn ball-like fluff has a magnitude | size 3 to 20 times the diameter of the filament (single fiber) which comprises a multifilament yarn. It is preferable to use the fluff detection method according to any one of 1 to 3.

  Next, as a fluff detector for solving the above-mentioned problem, the slit according to claim 5, which is smaller than the size of the fluffy fluff of the multifilament yarn that travels with the fluffy fluff. A guide that forms a gap, a passage resistance detector that detects a passage resistance that occurs when the yarn-like fluff passes through the gap, and a yarn-like fluff from the passage resistance detected by the passage resistance detector. A fluff detector including an abnormality determining means for determining passage is provided.

  In this case, it is preferable that the present invention is the “fluff detector according to claim 5, wherein the passage resistance detector is a load detector, a dynamic strain detector or a vibration detector”.

  As described above, the present invention according to claim 1 and claim 5 regulates the yarn path of the traveling yarn by the guide having the slit-shaped gap provided on the yarn path of the traveling multifilament yarn. Then, the yarn ball-shaped fluff (slab) generated on the yarn running through the gap of the guide collides with the guide to detect the fluff. Therefore, even if the yarn oscillates, the yarn is reliably caught by the guide and is not affected by the oscillation.

  Moreover, in the present invention, the yarn fluffs (slabs) are made to pass through the slit-like gaps made smaller (narrower) than this size, and the passage resistance at that time is detected. Even when traveling at high speed, the passage of the slab can be reliably detected. On the contrary, as the yarn travels at a higher speed, the reaction force generated by the yarn colliding with the guide increases, so that the passage resistance of the yarn can be detected with higher accuracy.

  At that time, as described in claim 2, when the present invention is applied to the yarn that has passed through the entanglement treatment for entanglement of the filament group constituting the multifilament yarn, the spinning process, the spinning direct drawing process, etc. By the entanglement process that is normally provided in the yarn making process, the cut filament can be made into a ball shape. For this reason, the process which makes it a ball shape can be skipped and it is preferable.

  Furthermore, unlike the non-contact type fluff detection method such as the light amount change detection method and the capacitance change detection method, the present invention adopts the contact type fluff detection method, so that the detection accuracy is lowered due to environmental changes due to oil smoke or the like. There is no need to do. In addition, since it is not a method of releasing fluff from the multifilament yarn Y using centrifugal force, it is not necessary to install a fluff detector in a dangerous place such as a rotating body that rotates at high speed, and the straight yarn Y It can also be applied to.

  Hereinafter, steps for applying the method and apparatus of the present invention will be described in order from the melt spinning step. First, in a melt spinning process, a polymer such as polyester is melted by a conventional method using a melt extruder or the like, and the polymer is sent to a spinning pack attached to a pack dome of a spin block by a metering means such as a gear pump. Next, a multifilament yarn Y is formed by continuously and quantitatively discharging molten polymer from a group of polymer discharge holes formed in a spinneret mounted on the spin pack.

  At this time, the temperature of the polymer discharge surface of the spinneret is kept warm by a heating cylinder provided directly below the spinneret, so that the thinning of the spun multifilament yarn Y can be optimally controlled. Delayed cooling control is performed, and cooling air is spun from the cooling spinning cylinder onto the yarn Y that has been spun in the direction of the arrow in the figure, and is once cooled below the glass transition temperature. Thereafter, a spinning oil is applied to the cooled yarn Y by an oil application device, and then taken up by a take-up roller to complete the melt spinning process.

  Next, the multifilament yarn Y melt-spun in this manner is led to a multi-stage drawing roller group composed of a pair of heating rollers, and is subjected to a drawing process in which multi-stage drawing is performed between these multi-stage drawing roller groups. Is done. At that time, the multifilament yarn Y guided to the drawing roller group is several turns to several turns in the multi-stage drawing roller group so that a sufficient time for the yarn Y to contact each drawing roller group is secured. It is wound ten turns. In this way, the yarn Y heated to a predetermined drawing temperature by sufficient contact with the drawing roller group is drawn to a predetermined drawing ratio between the drawing rollers in each stage.

  Next, the yarn Y drawn by the drawing roller group is finally entangled by the second entanglement imparting device, and then wound by the winder via the fluff detector 1. At this time, the second entanglement imparting device winds up a bobbin or the like as a wound body to form a yarn package, and then, when the yarn tries to unwind the multifilament yarn Y from the package, It plays an extremely important role in improving the unraveling ability. This is because if the multifilaments Y of the wound yarn are not entangled minutely, each filament is wound in a disjointed state, so that the filament may be caught during unwinding and the unwinding property This is because it is significantly worsened.

  The main feature of the fluff detection method and fluff detector of the present invention described above is to detect a cut filament (fluff) in a yarn ball shape. In the present invention, “yarn ball shape” means “after a single filament (single fiber) or a plurality of filament groups (single fiber group) is cut, the cut filament is wound around the yarn and entangled. "State". However, in this case, there is a case where a group of cut filaments released from the yarn is not entangled with the yarn main body and is entangled with each other apart from the yarn main body. Shall be included.

  With the above in mind, the fluff detector 1 of the present invention is provided after the second entanglement imparting device in the embodiment example in order to make the fluff into a ball shape. . Needless to say, the cut filament (fluff) is passed through the second entanglement imparting device for performing the entanglement process in which the filaments are entangled with each other by the force of the jetted compressed air. However, at the same time, if fluff is generated in the multifilament yarn Y, it grows into a ball-like fluff (hereinafter also referred to as “slab”) by the action of the jetted compressed air. Then, the slab formed in this way forms yarn ball-like fluff (hereinafter referred to as “slab”) entangled around the multifilament yarn described above.

  Therefore, the fluff detection method and the fluff detector 1 of the present invention are intended to reliably detect fluff by effectively using the slab formed in this way. Hereinafter, the fluff detection method and the fluff detector of the present invention will be described in detail with reference to the drawings (FIGS. 1 and 2).

  FIG. 1 is an explanatory view (perspective view) schematically illustrated for explaining a method for detecting fluff using the fluff detector 1 according to the present invention. 2A is a schematic side view, and FIG. 2B is a cross-sectional view in the X-X ′ direction in FIG. 2A (schematic flat cross-sectional view).

  In the embodiment illustrated in FIGS. 1 and 2, the fluff detector 1 according to the present invention includes a guide 11 having a gap G formed in a slit shape (in the illustrated example, a pair of rod-shaped guides 11a and 11b). Is supported by the support member 12 having elasticity, and is attached to the main body portion 14. Therefore, the support member 12 is restricted in the degree of freedom of movement so that the guide 11 can move only in the direction of the arrow shown in FIG. 3B (the vibration mode in the direction of expanding the guide 11), and has an elastic force. The yarn path of the multifilament yarn Y is gently regulated.

  1 and 2, the vibration detector 13 is in contact with the support member 12, and the multifilament yarn Y is in contact with the guide 11 as will be described in detail later. Detect vibrations that occur. The guide 11 is preferably made of a ceramic such as aluminum oxide or titanium oxide and provided with an appropriate surface roughness. This is because the friction coefficient for suppressing abrasion damage when the multifilament yarn Y travels in contact with the guide 11 can be reduced, and furthermore, static electricity generated by friction with the yarn Y can also be reduced. It is.

  Furthermore, in the fluff detection method and apparatus of the present invention, as described above, the slit-like gap G formed between the pair of rod-shaped guides 11a and 11b is formed by the slab S (the fluff that is in the shape of a yarn ball). When the formed multifilament yarn Y passes at a high speed (for example, 1000 m / min), the slab S acts to abruptly spread the guides 11a and 11b. Therefore, both guides 11a and 11b cause vibrations having a high frequency at the same time, and particularly when using a vibration detection sensor, by detecting vibrations having a frequency in this specific range, a conventional contact type fluff detector It is possible to prevent a decrease in detection accuracy and malfunction due to noise that has occurred. Incidentally, examples of such vibration detection sensors include commercially available vibration sensors (sensor head model: GH-513, amplifier unit: GA-223) manufactured by Keyence Corporation.

  As described above, the present invention is characterized in that the multifilament yarn Y traveling in the slit-like gap G formed in the guide 11 is guided. At this time, if a slab S is generated in the guided multifilament yarn Y, the slab S has a thread ball shape larger than the slit-shaped gap G, but the thread ball slab S is forcibly narrow. Since it must pass through the gap G, it receives a large passage resistance from the guide 11. That is, as compared to the case where the multifilament yarn Y not having the slab S passes through the gap G, when the slab S passes, a larger passage resistance or impact force is applied to the guide 11.

  In the present invention, the passage resistance or impact force transmitted to the guide 11 is detected in this way, and the fluff (filament breakage) generated in the multifilament yarn Y is used as a force (load) with a dynamic strain gauge as a load cell or strain. It is detected or particularly preferably detected as vibration (magnitude of amplitude or vibration frequency). 2 and 3, a pair of passage resistance detectors 13a and 13b are provided corresponding to the pair of rod-shaped guides 11a and 11b, respectively.

  As described above, the force propagated to the guides 11a and / or 11b is detected as a reaction force as it is by a load detector (load cell), or the propagated reaction force is detected as dynamic strain or vibration (frequency or amplitude). Once converted into a form, the passage resistance is detected by the passage resistance detector 13. Then, the detected passage resistance is quantified, and this is quantified to determine whether or not the slab S (that is, “fluff”) has passed.

  At this time, even if the traveling multifilament yarn Y may swing greatly, the yarn Y is provided by the pair of rod-shaped guides 11 provided on the yarn path of the yarn Y and formed with slit-like gaps. Is restrained, the passage resistance of the yarn Y can be reliably detected. In addition, unlike the non-contact type fluff detection method such as the light amount change detection method and the capacitance change detection method, the present invention employs the contact type fluff detection method, so that the detection accuracy decreases due to environmental changes due to oil smoke or the like. There is nothing. In addition, since it is not a method of releasing fluff from the multifilament yarn Y using centrifugal force, it is not necessary to install a fluff detector in a dangerous place such as a rotating body that rotates at high speed, and the straight yarn Y It can also be applied to.

  In the above-described passage resistance detector 13, the passage resistance when the slab S of the multifilament yarn Y passes through the guide 11 or the reaction force (impact force) generated by the collision of the slab S with the guide 11 is ensured. Can be detected. In addition, about the passage resistance detector which detects such passage resistance as reaction force (impact force) and its detection method, for example, a dynamic strain gauge is attached to the base of the guide 11 and is generated by the reaction force. It is obvious that a technique for detecting the amount of strain or a technique for directly detecting the reaction force as a load by providing a load detector (load cell) at the base of the guide 11 can be applied. Therefore, the detailed description is abbreviate | omitted here.

  In addition, as other detection technologies, vibration detectors that detect the propagation of vibration generated when the slab S collides with the guide 11 based on the vibration frequency and amplitude (vibration intensity) are mounted on both sides of the guide 11. Can also be used. In this case, the frequency of vibration generated when the slab S collides with the guide 11 is clearly different from the case where the multifilament yarn Y having a normal fiber diameter passes through the gap G, so the passage of the slab S is made clearer. Judgment can be made. Incidentally, examples of such vibration detection sensors include commercially available vibration sensors (sensor head model: GH-513, amplifier unit: GA-223) manufactured by Keyence Corporation.

  With the passage resistance detector 13 as described above, the passage resistance when the slab S passes through the gap G is an analog electric signal (voltage value or current value, etc.) consisting of load value, dynamic strain, vibration (amplitude value), etc. ) Is amplified as necessary via a signal amplifier (not shown), and then converted into a digital signal by an A / D converter (analog signal / digital signal converter) not shown. Is done. Then, the digitized signal value is input to an abnormality determination means 15 constituted by a microcomputer or the like via an interface circuit (not shown) or the like, and is set to a preset passage resistance obtained by a prior experiment. When the abnormality determining means 15 determines that the threshold level has been exceeded by comparing with the threshold level, it is recognized that the slab S of the multifilament yarn Y has passed through the gap G of the guide 11.

  At this time, when the passage resistance is quantified by the frequency of vibration as the passage resistance detector 13 and the passage of the slab S is detected by the abnormality determination means 15, it is represented by the tension of the traveling multifilament yarn Y. The passing resistance fluctuates rapidly when the slab S passes through the guide 11, and vibration having a higher frequency component than that in the normal state appears. Therefore, the passage resistance can be quantified or quantified by detecting such a frequency by the passage resistance detector 13, and this information can be sent to the abnormality judgment means 15 so that the passage of the slab S can be judged by the abnormality judgment means 15. In this case, since the passage resistance detector 13 is a vibration frequency detection method for detecting the frequency (frequency) in a specific range, naturally, natural frequencies such as mechanical vibration transmitted to the fluff detector 1 are removed in advance. Therefore, it is possible to determine that the fluff has passed through the gap G without being affected by noise.

  The guide 11 should have an appropriate surface roughness so as not to be damaged by contact with the guide 11 even when a normal multifilament yarn Y having no slab S passes. Is preferred. Further, the shape of the guide 11 is not particularly limited as long as it satisfies the gist of the present invention. However, if a thin flat bar guide is used, rigidity is lost due to its flexibility, causing vibrations, etc., and the noise caused by this decreases the detection accuracy. It cannot be accurately captured.

  For the reasons described above, the guide 11 needs to have a shape that has enough rigidity to withstand the collision force when it hits the slab S (but the support member 12 is elastic) The rod-shaped guide 11 having a curved surface with an appropriate curvature such as a round cross section is particularly preferable. This is because if the guide 11 has such a rod-shaped round cross-sectional shape, even if the multifilament yarn Y having no abnormality such as the slab S contacts the guide 11, the guide 11 is less likely to be damaged. Because it becomes.

  At this time, as a specific value of the gap G formed by the pair of rod-shaped guides 11a and 11b, an optimum value should be appropriately determined depending on conditions such as the fineness of the multifilament yarn Y, the running speed, and the polymer type. It is a design matter. That is, if the gap G is too narrow, it is not preferable because it causes great damage to the multifilament yarn Y that runs normally without fluff or scum accumulates, and conversely if the gap G is too wide. Further, the passage resistance of the fluff that is in the shape of a yarn ball becomes small, and it becomes difficult to accurately detect the occurrence of the fluff. Therefore, it is preferable that the proper value of the gap G is determined by experiment for the target multifilament yarn Y.

  However, if the gap G between the guides 11a and 11b is intentionally set, the gap G is desirably smaller than the slab S, specifically, 3 to 20 times the diameter of the filament (single fiber). If the gap G is less than three times the diameter of the filament (single fiber), the filament group constituting the multifilament yarn Y can be easily deformed into a flat shape when passing through the gap G. This is because it will receive a greater passage resistance and take damage. On the other hand, if the ratio is larger than 20 times, the yarn ball-like fluff passes through the gap G without receiving a large passage resistance, so that the fluff detection accuracy decreases.

  Further, at this time, the guide 11 of the fluff detector 1 is installed at two positions so that the installation direction of the guide 11 of the fluff detector 1 is at an angle of 90 ° so that the traveling yarn Y enters the right angle with respect to the gap G of the guide 11. Is preferred. This is because even if the slab S is flattened and passes through the slit-like gap G of the first guide 11 without receiving a large passage resistance, this time, the slit-like gap G perpendicular to the flat plane of the slab S is formed. This is because they get caught and receive a large passage resistance.

  As described in detail above, the fluff detection method and detector of the present invention are subjected to severe heat treatment in order to obtain a yarn having high physical properties. Can be suitably used in a process for producing a synthetic fiber by a direct spinning and drawing method, in which the occurrence of fragility is likely. Moreover, in such a spinning process, the multifilament yarn Y travels at a high speed of, for example, 1000 m / min or more. Even if the multifilament yarn Y is in such a high-speed traveling state, it is online. Can detect the occurrence of fluff. This is because, in the direct spinning drawing method, as described above, the entanglement process for easing the filaments is indispensable, and the yarn ball-like fluff can be generated by this entanglement process. Therefore, the fluff can be reliably detected by passing the fluff made into a ball shape through the narrow slit-shaped gap G.

  However, the fluff detection method and the detector according to the present invention described above have been described by taking the direct spinning drawing process as an example embodiment, but are also widely applicable to spinning processes for spinning multi-filament multifilament yarns. It is clear from the gist that this is possible.

It is explanatory drawing (perspective view) typically illustrated in order to demonstrate the detection method of the fluff using the fluff detector concerning this invention. FIG. 2A is a schematic side view of an example of the fluff detector of the present invention, FIG. 2A is a schematic side view, and FIG. 2B is a cross-sectional view taken along the line XX ′ in FIG. FIG.

Explanation of symbols

1: Fluff detector
11 (11a, 11b): Guide (a pair of rod-shaped guides)
12: Guide support member
13 (13a, 13b): Passing resistance detector
14: Fluff detector body
15: Abnormality judgment means
G: Gap
S: Slab (yarn-like fluff)
Y: Multifilament yarn

Claims (6)

  A cut filament (fluff) generated in the traveling multifilament yarn is formed into a yarn ball shape, and the multifilament yarn is introduced into the gap between a pair of guides formed with slit-like gaps. The passage resistance received from the pair of guides when the strip passes through the gap is quantified by converting it into force, dynamic strain, or vibration (frequency and / or amplitude), and the quantified value can be regarded as the passage of fuzz in advance. A fluff detection method for determining that a multifilament yarn having fluff has passed when a set value is satisfied.   The fluff detection method according to claim 1, wherein the yarn ball-shaped filaments are formed by interlacing filaments constituting a multifilament yarn.   The fluff detection method according to claim 2, wherein the fluff is detected online after the confounding process in the spinning direct drawing process.   The fluff detection method according to any one of claims 1 to 3, wherein the ball-like fluff has a size 3 to 20 times the diameter of a filament (single fiber) constituting a multifilament yarn.   A guide formed with a slit-like gap smaller than the size of the yarn-ball fluff of a multifilament yarn that travels with a yarn-ball fluff, and occurs when the yarn ball-like fluff passes through the gap. A fluff detector comprising: a passage resistance detector that detects passage resistance; and an abnormality determination unit that determines passage of a yarn-ball fluff from the passage resistance detected by the passage resistance detector.   The fluff detector according to claim 5, wherein the passage resistance detector is a load detector, a dynamic strain detector, or a vibration detector.

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