JP2020002484A - Ring/traveler system of ring type spinning machine - Google Patents

Abstract

To realize a long life of a ring/traveler system and a reduction of running-in operation time at the same time.SOLUTION: In a ring/traveler system of a ring type spinning machine that slides in a non-liquid lubricating environment, a plurality of cracks 15 are provided on a sliding surface of a traveler 12 and a ring 11 when the traveler 12 slides. Further, the plurality of cracks 15 has: an average value of the crack width of 0.5 μm or more and 1.5 μm or less; and an average value of the number of cracks in the plurality of cracks 15 of less than 400/cm.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a ring / traveler system for a ring spinning machine.

  In a ring / traveler system of a ring spinning machine, when winding a yarn on a bobbin, the traveler slides (slids) on the ring. At this time, the sliding surface between the traveler and the ring is liable to wear or seizure due to friction. Particularly, in recent years, in order to improve the productivity of the ring type spinning machine, the traveling speed of the traveler on the ring is increased, whereby the wear of the traveler and the ring tends to progress rapidly. If the wear of the traveler and the ring progresses rapidly, the life of the ring / traveler system is shortened, and it is necessary to frequently replace parts such as the traveler. Generally, the wear of the traveler and the ring progresses faster as the frictional force generated on the sliding surfaces of the two increases. Therefore, as a method of suppressing wear of the traveler and the ring, for example, there is a method of using a lubricant such as oil. However, in this method, the yarn is stained by the adhesion of the lubricating liquid.

  Therefore, Patent Document 1 relates to a ring / traveler system of a ring type spinning machine that slides in a non-liquid lubricating environment and has a concave portion of 400 or more / cm on a sliding surface between the traveler and the ring when the traveler slides. The invention has been described. The document also describes that the concave portion is a microcrack formed on the surface of the hard chromium plating layer. According to the invention described in the document, by forming a plurality of microcracks on the sliding surface between the traveler and the ring, fibers falling off from the yarn during spinning are held by the microcracks to form a thin film, The lubrication function of this thin film provides a friction reducing effect. Therefore, the life of the ring / traveler system can be extended.

JP 2014-29046 A

However, the inventors of the present application have conducted intensive studies on the invention described in Patent Document 1 and found that there are the following new problems.
That is, in the invention described in the document, since microcracks of 400 / cm or more are formed on the sliding surface between the traveler and the ring, the surface roughness of the sliding surface increases due to the presence of the microcracks. Then, the initial sliding resistance when the traveler slides on the ring increases, and the time until the desired friction reducing effect is obtained, that is, the running-in operation time becomes longer.

  SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a ring / traveler for a ring type spinning machine that can simultaneously achieve a longer life of a ring / traveler system and a shorter running-in operation time. To provide a system.

  The present invention relates to a ring / traveler system of a ring type spinning machine that slides in a non-liquid lubricating environment, wherein a plurality of cracks are formed on a sliding surface between the traveler and the ring when the traveler slides. A ring / traveler system for a ring type spinning machine, wherein an average value of crack widths is 0.5 μm or more and 1.5 μm or less, and an average value of the number of cracks in the plurality of cracks is less than 400 / cm.

  In the ring / traveler system of the ring spinning machine of the present invention, the average value of the crack widths in the plurality of cracks may be 0.6 μm or more.

  In the ring / traveler system of the ring spinning machine according to the present invention, the average number of cracks in the plurality of cracks may be 380 / cm or less.

  ADVANTAGE OF THE INVENTION According to this invention, extension of the life of a ring / traveller system and shortening of a running-in operation time can be simultaneously realized.

Fig. 3 shows a configuration example of a ring / traveler system of a ring type spinning machine, wherein (a) is a perspective view of a ring, (b) is a partially enlarged perspective view of the ring, and (c) is a relationship between a traveler and a ring during spinning. It is a perspective view which shows typically. It is a schematic diagram of a friction reduction section. FIG. 9 is a diagram illustrating evaluation results of a conventional example, an example, and a comparative example. It is a figure which shows the relationship between a sliding resistance and a sliding distance. FIG. 9 is a view showing the result of observing a plated surface of a ring corresponding to a conventional example with an electron microscope. It is a figure showing the result of having observed the plating surface of the ring corresponding to an example with an electron microscope. It is a figure showing the result of having observed the traveler wear powder on a ring with an electron microscope.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIGS. 1A and 1B show an example of the configuration of a ring / traveler system of a ring type spinning machine. FIG. 1A is a perspective view of a ring, FIG. 1B is a partially enlarged perspective view of the ring, and FIG. It is a perspective view which shows the relationship of a ring typically. “Ring type spinning machine” means a spinning machine such as a ring spinning machine or a ring twisting machine that winds a yarn via a traveler that slides on a ring supported by a ring rail and moving up and down.

1A to 1C, a ring 11 and a traveler 12 constitute a ring / traveler system. Ring 11 is made of, for example, bearing steel. The ring 11 has a flange 11a. The flange 11a is formed integrally with the ring 11 and has a T-shaped cross section.
On the other hand, the traveler 12 is made of, for example, oxidized spring steel. The traveler 12 is formed in a C shape. The traveler 12 is attached to the flange 11 a of the ring 11.

  A chrome plating layer 13 is formed on the surface of the flange 11a of the ring 11. The chromium plating layer 13 is preferably a hard chromium plating layer, and is formed to a thickness of, for example, about 10 to 20 μm. The hard chrome plating layer refers to a plating layer defined in JIS H8615 industrial chrome plating. Of the chrome plating layer 13 covering the flange 11a, a friction reducing portion 14 is formed at least on the surface layer of the chrome plating layer 13 covering the inner peripheral surface of the flange 11a. The friction reducing part 14 is a part of the chrome plating layer 13 and is a part that reduces a frictional force generated when the traveler 12 slides on the ring 11. The mechanism of friction reduction by the friction reduction unit 14 will be described later.

  When the yarn is wound around the bobbin by the ring spinning machine, the yarn Y is passed through the traveler 12 as shown in FIG. The yarn Y is sent out from a draft device (not shown), and is wound around a bobbin (not shown) via the traveler 12. At this time, a predetermined tension is applied to the yarn Y passed through the traveler 12. For this reason, the traveler 12 is pulled by the yarn Y and comes into contact with the flange 11a of the ring 11, and moves around the flange 11a while maintaining the contact state. Therefore, while the yarn Y is being wound on the bobbin, that is, during spinning, the ring 11 slides (slids) on the traveler 12.

  Here, the sliding surface between the traveler 12 and the ring 11 when the traveler 12 slides is a surface where the ring 11 and the traveler 12 are in contact with each other. For this reason, the sliding surface between the traveler 12 and the ring 11 exists on both the ring 11 and the traveler 12. In the present embodiment, as an example, the sliding surface of the ring 11 with respect to the traveler 12 is used as the friction reducing portion 14. Specifically, a configuration is adopted in which the inner peripheral surface of the flange 11a of the ring 11 is covered with a chrome plating layer 13, and a friction reducing portion 14 is formed on the surface of the chrome plating layer 13. Therefore, in the present embodiment, the friction reducing portion 14 of the chrome plating layer 13 covering the inner peripheral surface of the flange 11a corresponds to a sliding surface between the traveler 12 and the ring 11.

  A plurality of cracks 15 are formed in the friction reducing portion 14 of the chrome plating layer 13 as shown in FIG. The length and direction of the plurality of cracks 15 are random. The crack 15 is preferably a crack having a size of 250 / cm or more, that is, a microcrack, defined in JIS H8615 industrial chrome plating.

In the present embodiment, the plurality of cracks 15 formed in the friction reducing section 14 simultaneously satisfy the following two conditions.
(Condition 1) The average value of the crack width in the plurality of cracks 15 is 0.5 μm or more and 1.5 μm or less.
(Condition 2) The average number of cracks in the plurality of cracks 15 is less than 400 / cm.

The crack width is obtained, for example, by photographing the surface of the friction reducing portion 14 of the chromium plating layer 13 with a microscope, and measuring the width of the crack 15 in the micrograph obtained by using a scale bar of the microscope. It can be specified by the following.
The number of cracks is determined, for example, by photographing the surface of the friction reducing portion 14 of the chromium plating layer 13 with a microscope, drawing a straight line on the micrograph obtained by the photographing, and calculating the number of cracks 15 intersecting with the straight line having a length of 1 cm. It can be specified by counting the number. At this time, since the length and the direction of the crack 15 are random, it is not necessary to particularly set a position in the micrograph at which a straight line is drawn.
In the friction reducing portion 14 of the chromium plating layer 13, the crack width and the number of cracks in the plurality of cracks 15 all vary in a normal distribution or a distribution close thereto.

  By the way, when the chromium plating layer 13 is formed on the ring 11 by the chromium plating, the crack 15 that satisfies the above two conditions cannot be formed only by the chromium plating. Therefore, in the present embodiment, after forming the chromium plating layer 13 on the ring 11 by chromium plating, electrolytic cracking is performed to form cracks 15 that simultaneously satisfy the above two conditions.

  At that time, the etching conditions of the electrolytic etching were determined so that the average value of the crack widths in the plurality of cracks 15 was 0.5 μm or more and 1.5 μm or less, and the average value of the number of cracks was less than 400 / cm. . The etching conditions include, for example, current density and etching time.

  Here, when the average value of the crack width is less than 0.5 μm, the width of the crack 15 is excessively small with respect to the particle size of the wear powder generated on the sliding surface of the ring 11 and the traveler 12. For this reason, it is not possible to smoothly release the wear powder generated on the sliding surface into the crack 15. In addition, although wear powder having a relatively small particle size can escape to the crack 15, the crack 15 is filled with the wear powder in a short period of time because the amount of the wear powder that can be accepted is small in the narrow crack 15. Would. On the other hand, if the average value of the crack width is increased, the wear powder generated on the sliding surface can be smoothly released to the crack 15 and the period until the micro crack is filled with the wear powder can be ensured long. Can be. However, if the average value of the crack widths exceeds 1.5 μm, the unevenness on the surface of the friction reducing portion 14 becomes apparent due to the presence of the wide cracks 15, and the sliding surface between the ring 11 and the traveler 12 tends to wear. Therefore, the average value of the crack width is preferably 0.5 μm or more and 1.5 μm or less. In order to allow the wear powder to quickly escape to the cracks 15, the average value of the crack width is more preferably 0.6 μm or more, and further preferably 0.7 μm or more. Further, in order to suppress the occurrence of wear on the sliding surface, the average value of the crack width is more preferably 1.3 μm or less, and further preferably 1.2 μm or less.

  On the other hand, with respect to the number of cracks, if the average value of the number of cracks is 400 / cm or more, the surface roughness of the friction reducing unit 14 increases, and accordingly, the running-in operation time of the ring spinning machine increases. The surface roughness is a term indicating the property of the surface of an object, and is evaluated by the number of irregularities per unit length on the surface of the object. That is, the surface roughness increases as the number of irregularities per unit area on the object surface increases, and the surface roughness decreases as the number of irregularities decreases. For this reason, if the average value of the number of cracks is increased to 400 / cm or more, the surface roughness of the friction reducing portion 14 increases accordingly.

  On the other hand, the running-in operation time refers to the time required for the friction reducing unit 14 to exhibit a desired friction reducing effect when the yarn is wound around the bobbin using the new ring 11 and the traveler 12, respectively. . In order to shorten the running-in time, it is advantageous to lower the surface roughness of the friction reducing section 14 so as to reduce the initial sliding resistance. The initial sliding resistance is a sliding resistance generated when the traveler 12 slides on the new ring 11, and particularly means a sliding resistance in a range where the sliding distance is more than 0 km and 500 km or less. When there are many irregularities on the surface of the friction reducing portion 14, the initial sliding resistance increases, and the time until the cellulose fibers spread over the entire surface of the friction reducing portion 14, as described in the friction reduction mechanism described below, The time required until the desired friction reducing effect is obtained becomes longer. Therefore, the average value of the number of cracks is preferably less than 400 / cm. In order to suppress the increase in the surface roughness due to the cracks 15, the average value of the number of cracks is more preferably 380 / cm or less, and further preferably 370 / cm or less. However, when the average value of the number of cracks is excessively small, the number of cracks 15 holding the cellulose fibers may be insufficient, and the friction reducing effect by the friction reducing unit 14 may not be sufficiently obtained. Therefore, the average value of the number of cracks is preferably at least 250 / cm, more preferably at least 300 / cm.

Here, the mechanism of friction reduction by the friction reduction unit 14 will be described.
First, in the present embodiment, the sliding surface between the ring 11 and the traveler 12 is a surface that slides under sliding in a non-liquid lubricating environment. Non-liquid lubrication refers to a state in which no liquid lubricant is present. Generally, when metals slide under non-liquid lubrication, severe abrasion occurs on the sliding surface. In particular, in the ring / traveler system, since the traveler 12 moves around the ring 11 at a high speed, wear is rapidly progressed on the sliding surfaces of the two, and it is expected that seizure will occur in a few minutes to a few hours. However, in a real ring / traveler system, wear progresses slowly, contrary to expectations. For example, in cotton spinning, the traveler 12 can often be used without replacement for about one to two weeks. Therefore, it is considered that the sliding surface between the ring 11 and the traveler 12 is not lubricated tribologically but is in a boundary lubrication state. The analysis performed by the present inventors has revealed that a cellulose coating is formed on the sliding surface on which the traveler 12 slides on the ring 11, and that this coating performs a lubricating function to obtain a friction reducing effect. Cellulose is contained in cotton or the like which is a raw material of the yarn Y. For this reason, it is presumed that the cellulose fibers detached from the yarn Y passing through the traveler 12 during the spinning, and the fibers entered the contact interface between the ring 11 and the traveler 12, that is, the sliding surface to form a coating. You.

  In the ring / traveler system of the present embodiment, a plurality of cracks 15 are formed on the sliding surface between the ring 11 and the traveler 12 when the traveler 12 slides. Therefore, when the cellulose fiber released from the yarn Y enters the sliding surface between the ring 11 and the traveler 12, the fiber is adhered and held in each crack 15 formed on the sliding surface, and The contained lubricating component (mainly carbon) spreads thinly in the form of a film. As a result, a coating made of cellulose fibers is formed on the sliding surface between the ring 11 and the traveler 12, and a friction reducing effect is obtained by the lubricating function of the coating. Therefore, even under non-liquid lubrication, the frictional force generated on the sliding surface between the ring 11 and the traveler 12 can be reduced, and the wear of the ring 11 and the traveler 12 can be suppressed.

In order to confirm the friction reducing effect of the friction reducing unit 14, the present invention evaluated the life of the component using four rings 11 having different crack 15 forming conditions. The results are shown in FIGS.
In FIG. 3, the products to be evaluated are separately described as a conventional example, an example, a comparative example 1, and a comparative example 2. In the conventional example, the surface of the ring 11 is only chrome-plated. In this embodiment, the surface of the ring 11 is subjected to chromium plating and then subjected to electrolytic etching under the conditions of a current of 2 A and an etching time of 120 sec. In Comparative Example 1, the surface of the ring 11 was subjected to chromium plating, followed by electrolytic etching under the conditions of a current of 4 A and an etching time of 120 sec. In Comparative Example 2, after the surface of the ring 11 was subjected to chromium plating, electrolytic etching was performed under the conditions of a current of 4 A and an etching time of 240 sec.

  FIG. 5 is a diagram showing the result of observing the plating surface of the ring corresponding to the conventional example with an electron microscope, and FIG. 6 is a diagram showing the result of observing the plating surface of the ring corresponding to the example with an electron microscope. is there. FIG. 7 is a diagram showing the result of observing the traveler wear powder on the ring with an electron microscope. As can be seen by comparing FIGS. 5 and 6, cracks on the plating surface are not clearly seen in the conventional example, but cracks on the plating surface are clearly seen in the example. It is considered that the reason is that the size of the fine cracks generated on the surface of the chromium plating layer 13 by the chromium plating treatment was increased in the width direction and the depth direction by the electrolytic etching. On the other hand, as shown in FIG. 7, the wear powder generated on the sliding surfaces of the ring 11 and the traveler 12 has a slight variation in the particle size of the wear powder, but tends to have a uniform particle size as a whole.

  Due to the difference in the processing conditions described above, the average value of the crack width was less than 0.5 μm in the conventional example, 0.74 μm in the example, 1.07 μm in Comparative Example 1, and 2.01 μm in Comparative Example 2 due to the difference in the processing conditions described above. . The standard deviation of the crack width was 0.26 μm in the example, 0.42 μm in Comparative Example 1, and 0.83 μm in Comparative Example 2. On the other hand, regarding the average value of the number of cracks, the conventional example was 151.5 pieces / cm, the example was 356.5 pieces / cm, the comparative example 1 was 573.8 pieces / cm, and the comparative example 2 was 896.9 pieces / cm. cm. Regarding the standard deviation of the number of cracks, the conventional example was 51.0 / cm, the example was 56.0 / cm, the comparative example 1 was 139.0 / cm, and the comparative example 2 was 127.2 / cm. cm.

  On the other hand, the life of the parts is evaluated by setting the number of rotations of the spindle which determines the rotation speed of the bobbin to 20,000 rpm, and sliding the traveler 12 while sliding on the ring 11 until the traveler 12 comes off the flange 11a due to wear. did. As a result, regarding the life of the parts, the conventional example was 1890 km, the example was 7091 km or more, the comparative example 1 was 7091 km or more, and the comparative example 2 was 3072 km. In addition, the life of each of the example and the comparative example 1 was 7091 km or more, because the evaluation test was terminated when the traveling distance of the traveler became 7091 km.

  As can be seen from the above evaluation results, in the example and the comparative example 1, the life of the component is more than three times longer than that of the conventional example. However, in the case of Comparative Example 1, the average value of the number of cracks was a large value of 573.8 / cm. For this reason, in Comparative Example 1, the surface roughness of the friction reducing unit 14 increases, and the running-in operation time increases.

  In FIG. 4, the vertical axis represents the traveling resistance (gf) of the traveler, and the horizontal axis represents the traveling distance (km) of the traveler. For each of the conventional example, the example, the comparative example 1, and the comparative example 2, the sliding distance is long. It shows how the sliding resistance changes as it goes. The sliding resistance was determined by rotatably supporting the ring and measuring the co-rotating force applied to the ring by the traveler in this state with a load cell. As a result, in the conventional example, the sliding resistance starts to increase sharply when the sliding distance exceeds 1000 km, and the component reaches the life. In Comparative Example 2, the sliding resistance starts to increase sharply when the sliding distance exceeds 2000 km. The component has reached its end of life.

  In contrast, in the example, no sharp increase in the sliding resistance was observed even when the sliding distance exceeded 2,000 km, and this tendency was maintained even when the sliding distance exceeded 7000 km. Further, in Comparative Example 1, although the variation in the sliding resistance was larger than that in the example, the evaluation result was the same as the example in terms of the life. However, comparing the initial sliding resistance, the sliding resistance of the example was smaller than that of Comparative Example 1. The reason is presumed to be that the average value of the number of cracks in the example is smaller than that in the comparative example 1, thereby suppressing an increase in the surface roughness of the friction reducing section 14.

<Effects of Embodiment>
According to the embodiment of the present invention, the following effects can be obtained.
In the present embodiment, the average value of the crack width in the plurality of cracks 15 formed on the sliding surface between the ring 11 and the traveler 12 is 0.5 μm or more and 1.5 μm or less. Thus, the wear powder generated on the sliding surface between the ring 11 and the traveler 12 can be smoothly released into the crack 15 and the state in which the crack 15 is not filled with the wear powder can be maintained for a long time. Therefore, the friction reducing effect by the friction reducing unit 14 can be enhanced, and the high friction reducing effect can be maintained for a long time. In the present embodiment, the average value of the number of cracks in the plurality of cracks 15 is less than 400 / cm. For this reason, it is possible to suppress an increase in the surface roughness of the friction reducing portion 14, reduce the initial sliding resistance, and shorten the time required for the cellulose fibers to spread over the entire surface of the friction reducing portion 14. As a result, according to the present embodiment, it is possible to simultaneously extend the life of the ring / traveler system and reduce the running-in operation time.

<Modifications, etc.>
The technical scope of the present invention is not limited to the above-described embodiments, but includes various modifications and improvements as long as specific effects obtained by the constituent features of the invention and combinations thereof can be derived.

  For example, in the above-described embodiment, the flange 11a of the ring 11 is covered with the chrome plating layer 13, but the invention is not limited to this, and the entire surface of the ring 11 including the flange 11a is covered with the chrome plating layer 13. Is also good.

  Further, in the above embodiment, the ring 11 is subjected to electrolytic etching after the chromium plating layer 13 is formed by chromium plating, but the present invention is not limited to this. For example, chemical etching is applied instead of electrolytic etching. You may.

  Further, in the above embodiment, of the ring 11 and the traveler 12, the friction reducing portion 14 is formed on the ring 11 side. However, the present invention is not limited to this, and the friction reducing portion 14 may be formed on the traveler 12 side. The friction reducing portion 14 may be formed on both the ring 11 and the traveler 12.

  The yarn to be spun is not limited to cotton, and may be, for example, hemp, silk, wool, or chemical fiber (nitrocellulose, nylon, vinylon).

  Further, the ring 11 constituting the ring / traveler system is not limited to the one having the flange 11a having a T-shaped cross section, and may be one having an inclined flange, for example. In that case, a traveler having a shape adapted to the inclined flange is used.

  11 ring, 12 traveler, 14 friction reduction part (sliding surface), 15 cracks.

Claims (3)

  In a ring / traveler system of a ring type spinning machine that slides in a non-liquid lubricating environment, a plurality of cracks are formed on a sliding surface between the traveler and the ring when the traveler slides, and an average of crack widths in the plurality of cracks is provided. A ring / traveler system for a ring type spinning machine, wherein the value is 0.5 μm or more and 1.5 μm or less, and the average value of the number of cracks in the plurality of cracks is less than 400 / cm.   The ring / traveler system of a ring type spinning machine according to claim 1, wherein the average value of the crack widths in the plurality of cracks is 0.6 µm or more.   The ring / traveler system of a ring spinning machine according to claim 1 or 2, wherein the average value of the number of cracks in the plurality of cracks is 380 / cm or less.

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