WO2012147851A1 - Circular string knitting machine comprising latch flip prevention unit - Google Patents

Abstract

The present invention relates to a knitting machine (1) where a plurality of latch needles (8) comprising a latch (28) disposed in a circumferential direction of a hollow core rod (5) are supported for a reciprocating motion along an axial direction of the core rod (5), and a guide (31) which guides a thread (40) supplied to the latch needle (8) is disposed rotatably on the core rod (5) as a central axis. According to the knitting machine of the present invention, the latch (28) of the latch needle (8) arranges the guide (31) at a position where the thread (40) is routed in a range of rotation of the latch (28) of the latch needle (8) immediately after the latch (28) falls out of a previously formed roof.

Description

String-like circular knitting machine equipped with a mechanism to prevent latch jumping

This invention relates to a string-like circular knitting machine equipped with a latch jump-up prevention mechanism. The present invention also relates to a circular knitting machine capable of high-speed operation in a circular knitting machine for knitting a cylindrical string, which is used for a hollow porous membrane support. The present application is filed on April 26, 2011, Japanese Patent Application No. 2011-098202 filed in Japan, August 26, 2011, Japanese Patent Application No. 2011-185157, filed in Japan, and September 6, 2011. In addition, we claim priority based on Japanese Patent Application No. 2011-193803 filed in Japan, the contents of which are incorporated herein.

Conventionally, a circular knitting machine for manufacturing a string-like product by circular knitting of yarn is known. The circular knitting machine includes an outer cylinder that rotates around a hollow core rod, and the outer cylinder is provided with a yarn guide that guides a yarn supplied from a bobbin. A plurality of knitted needles (also referred to as latch needles or Bella needles) protruding from the end face of the outer cylinder along the outer peripheral surface of the core bar are provided so as to be movable up and down. The yarn guide guides the supplied yarn to a predetermined position of the knitted needle (see Patent Document 1).
The knitting needle is provided with a latch that opens and closes so that the thread locked during the lowering operation cannot be removed. Since this latch needs to be opened to lock the next thread when the knitting needle is raised, a circular knitting with a latch presser that prevents the latch from closing when the knitting needle is raised. (See Patent Document 2).

In recent years, interest in environmental pollution has increased and regulations on water quality have been strengthened, and water treatment using filtration membranes with excellent separation integrity and compactness has attracted attention. A hollow porous membrane is used as such a water treatment filtration membrane, and this hollow porous membrane requires not only excellent separation characteristics and permeation performance, but also high mechanical characteristics.

As a hollow porous membrane having excellent mechanical properties, for example, a porous porous membrane support made of a cylindrical braid formed by rounding a thread (hereinafter also referred to simply as a support) may be porous. A hollow porous membrane provided with a membrane layer is known. This hollow porous membrane is made by continuously passing the support through an annular nozzle, discharging the film-forming stock solution from the annular nozzle, applying the film-forming stock solution to the outer peripheral surface of the support, and then applying the film-forming stock solution. The support is passed through the coagulation bath and the film-forming stock solution is coagulated with the coagulation solution in the coagulation bath.

円 筒 Cylindrical braid as a support is usually manufactured by a string making machine. In a stringing machine, each thread is pulled out from a large number of bobbins erected on a flat plate, each thread is crossed and assembled, and each bobbin is moved along a predetermined path to thereby determine the positional relationship of the threads. A braid is manufactured by changing the pattern in a predetermined pattern.

However, in such a stringing machine, since a large number of subdivided bobbins move in a complicated manner, the stringing speed of the cylindrical braid by the stringing machine is usually about 10 to 20 m / hr. There is a problem that it is difficult to increase the speed further and productivity is low. Thus, when productivity is low, the cost of a support body (cylindrical braid) will rise, As a result, it will also lead to the cost increase of the hollow porous membrane which uses a support body.

As means for improving productivity, the present inventors have knitted a cylindrical braid by circular knitting as disclosed in Patent Document 3 and Patent Document 4 below, and thus have a machine equivalent to a cylindrical braid. Supports that have properties (pressure strength, tensile strength, etc.) and better productivity than braids, and pass cylindrical braids through heated heat treatment molds at temperatures below the melting temperature of the material It has been found that a cylindrical braided string support (hereinafter referred to as a braided string support) with reduced stretchability (change in outer diameter) is obtained by performing the treatment, and a support for a hollow porous membrane based on this A body manufacturing method and apparatus have already been proposed.

The outer diameter of the braided string support is determined by the outer diameter of the hollow porous membrane. The outer diameter of the hollow porous membrane is preferably 0.9 to 6.0 mm, more preferably 1.0 to 3.5 mm, from the required filtration area in the membrane module in which the hollow porous membranes are bundled. Therefore, the outer diameter of the support is preferably 0.7 to 5.0 mm, more preferably 0.9 to 3.0 mm.

The heat treatment mold described above has an outlet inner diameter smaller than the inner diameter of the inlet through which the cylindrical braid is introduced and is the same as the desired outer diameter of the braid support, and the cylindrical braid is heated and heated when passing through the inside. Shrinkage occurs and the stitches become dense. Therefore, the outer diameter of the cylindrical string knitted by the circular knitting machine needs to be larger than the desired outer diameter of the braided string support.

The fineness of the yarn is preferably 150 to 1000 dtex from the viewpoint of improving the durability of the hollow porous membrane and the adhesion to the porous membrane layer. If the fineness of the yarn is 150 dtex or more, although depending on the outer diameter, the crushing pressure of the hollow porous membrane is improved. When the fineness of the yarn is 1000 dtex or less, a decrease in water permeability due to a reduction in the inner diameter can be suppressed.

The number of stitches of the cylindrical braid is preferably 5 or more per round. The number of stitches is the same as the number of knitting needles (knitting needles) of the circular knitting machine described later. If the number of stitches is 5 or more, the cross-sectional shape of the hollow part of the braided string support body is circular, and a decrease in water permeability due to a reduction in the inner diameter can be suppressed.
The upper limit of the number of stitches is determined by the outer diameter of the cylindrical knitted string, the fineness of the yarn, the size of the stitch (the size of the loop), and the like. When the stitches are large, there is a possibility that when the film-forming stock solution is applied to the knitted string support, the film-forming stock solution flows into the knitted string support and the hollow portion is blocked. Therefore, when manufacturing a cylindrical knitted string having the same outer diameter, it is necessary to set a small number of stitches when the yarn fineness is high, and to set a large number of stitches when the fineness is low.

In the manufacturing method and manufacturing apparatus already disclosed by the present inventors, a method of increasing the rotational speed of the circular knitting machine to improve the productivity is taken in order to improve productivity, and the rotational speed is 3000 min depending on the manufacturing conditions. ^May exceed ^-1 . In general, the rotational speed of a circular knitting machine for knitting a knitted string is 500 to 1000 min ⁻¹ , and the rotational speed of the circular knitting machine in these manufacturing methods and apparatuses is more than three times the normal speed, and constitutes a circular knitting machine Parts, especially the knitting needles and the cam crests that slide with the knitting needles, are severely deteriorated, and the durability of the circular knitting machine is significantly reduced. In that case, the frequency of maintenance such as device stoppage due to component breakage during operation and replacement of components increases, leading to a decrease in productivity.

As a means for increasing the rotational speed of the circular knitting machine, Patent Document 5 does not disclose a method of rotating the outer cylinder by fixing a general core rod, but conversely, fixing the outer cylinder to be the center of the rotating shaft. A circular knitting machine capable of knitting at a rotational speed of 2500 min ⁻¹ by rotating a cylinder (core bar) in which a needle is disposed is disclosed.

Japanese Utility Model Publication No. 60-193993 Japanese Utility Model Publication No. 48-89950

JP 2008-114180 A JP 2009-052190 A Japanese Patent Laid-Open No. 02-307933

However, if the above-described conventional latch presser is provided in the yarn guide, the weight of the yarn guide guide attached to a part of the outer cylinder in the circumferential direction is increased by the amount of the latch press, and the dynamic balance is deteriorated. As a result, in order to prevent vibration generated during rotation, the number of rotations of the outer cylinder must be limited, and the stringing speed does not increase, resulting in a decrease in productivity.
Further, since the latch hits the latch press many times as the outer cylinder rotates, there is a problem that durability of the knitted needle is lowered.

Therefore, an object of the present invention is to provide a string-like circular knitting machine provided with a latch spring-up preventing mechanism that can suppress the generation of vibration and increase productivity even if the string making speed is increased.

In addition, even if high-speed rotation is possible by rotating the core rod, the friction force of the knitting needle, the cam that slides with the knitting needle, and the groove portion into which the knitting needle is inserted is the same. The wear deterioration of the moving part is the same as that of a circular knitting machine that rotates a general outer cylinder. There is no description about measures against wear in the disclosed document, and it is estimated that high speed operation for a long time is difficult as described above.
Moreover, even if the wear on the cam side can be suppressed, it can be presumed that the wear on the knitting needle bat portion side having a low hardness is conversely accelerated, and the replacement frequency of the knitting needle increases, leading to a decrease in productivity.
Accordingly, the present invention provides a support for a hollow porous membrane capable of producing a cylindrical knitted string with high productivity by suppressing wear of parts constituting the circular knitting machine even when the rotational speed of the circular knitting machine is increased. There is also provided a circular knitting machine for knitting a cylindrical knitted string used in the present invention.

The present invention has the following aspects.

According to a first aspect of the present invention, a plurality of knitting needles having a latch arranged in a circumferential direction of a hollow core rod are supported so as to be reciprocable along the axial direction of the core rod, and are supplied to the knitting needles. A knitting machine provided with a guide for guiding the yarn to be rotated around the core rod as a central axis;
A knitting machine in which the guide is disposed at a position where the yarn is routed within a rotation range of the latch of the knitted needle immediately after the latch of the knitted needle is released from the loop knitted previously.

According to a second aspect of the present invention, a plurality of knitting needles arranged in the circumferential direction of a hollow core rod are supported so as to be reciprocable along the axial direction of the core rod, and guide the yarn supplied to the knitting needles. A knitting machine provided so that the guide rotates about the core rod as a central axis,
It is a knitting machine having a latch pressing portion (also referred to as a latch rebound prevention portion or a latch rebound prevention mechanism) by the yarn between the guide and a position where a hook of a knitted needle is engaged with the yarn.

According to a third aspect of the present invention, an outer cylinder is rotatably supported by the core rod, and a plurality of knitted needles arranged in the circumferential direction with respect to the core rod can move up and down along the axial direction of the core rod. A string knitting circular knitting machine provided with a yarn guide that is supported and guides a yarn supplied to the knit needle that protrudes and moves up and down from the end of the outer cylinder,
Within the turning range of the latch of the knitted needle (for example, the turning range B in the embodiment) immediately after the latch is released from the loop during the ascending operation, and the next thread is about to be locked to the hook in the descending operation. The guide hole is positioned so as to be positioned on the extended line of the path along the circumscribed surface of the knitted needle connecting between the hook position of the knitted needle (locking range) (for example, the locking range C in the embodiment). It is a knitting machine in which a yarn guide guide is provided on an outer cylinder.

According to a fourth aspect of the present invention, in the circumferential direction of the core rod, the position of the guide ranges from 45 degrees to 100 degrees from the position of the knitted needle at the top dead center position toward the rotation direction of the guide. The knitting machine according to the third aspect, wherein the knitting machine is set within a range of 2 mm upward and 4 mm downward from the hook in the vertical direction of the hook of the knitted needle at the top dead center position. It is.

A fifth aspect of the present invention is the knitting machine according to any one of the first to fourth aspects, wherein the number of the knitting needles is in the range of 5 to 16.

A sixth aspect of the present invention is the knitting machine according to the fifth aspect, wherein the guide groove has a bottom circumferential diameter in the range of 3 to 14 mm.

A seventh aspect of the present invention is the knitting machine according to the sixth aspect, wherein the knitted fabric to be knitted has an outer diameter in the range of 3 to 8 mm.

The eighth aspect of the present invention is the knitting machine according to the seventh aspect, wherein the cylindrical knitted string used for the support for the hollow porous membrane is knitted.

A ninth aspect of the present invention is the knitting machine according to the eighth aspect, wherein a rotational speed of the outer cylinder is set in a range of 1800 to 4500 min ⁻¹ .

According to a tenth aspect of the present invention, there is provided a plurality of guide grooves for supporting the knitted needle in a longitudinal direction of the outer peripheral surface of the core bar so as to be movable up and down along the axial direction of the core bar. Are provided with two cylindrical cams for imparting up and down movement to the knitting needle, and includes a space portion in the outer cylinder including a sliding portion of a cam crest with which the cam and the knitting needle abut, and each guide groove. The knitting machine according to any one of the third to ninth aspects, wherein grease containing a solid lubricant is filled and enclosed.

An eleventh aspect of the present invention is the knitting according to the tenth aspect, wherein the solid lubricant is selected from the group consisting of organic molybdenum, molybdenum disulfide, PTFE, aluminum oxide, zinc oxide, and cubic boron nitride. Machine.

In another preferred aspect of the present invention, an outer cylinder (for example, the outer cylinder 7 in the embodiment) is rotatably supported by a core rod (for example, the core rod 5 in the embodiment), and is arranged in the circumferential direction of the core rod. A plurality of knitted needles (for example, the knitted needle 8 in the embodiment) protruding from the end of the outer cylinder are hooked (for example, the hook 27 in the embodiment) that is opened and closed by a latch (for example, the latch 28 in the embodiment). A thread guide (for example, a thread in the embodiment) that supports the thread (for example, the thread 40 in the embodiment) that is supported so as to move up and down along the axial direction of the core rod while being moved up and down. In the method of preventing the latch jumping of the string-like circular knitting machine provided with the guide guide 31), the latch of the knitted needle is looped (for example, in the embodiment) during the raising operation. The position where the hook of the descending knitting needle is locked to the thread, the position of the guide hole of the thread guide (for example, the guide hole 34 in the embodiment), It is characterized in that it is pressed by a thread that is arranged so as to be in contact with the plurality of knitted needles on the outside.
With this configuration, the thread itself supplied to the knitting needle is effectively used, and during the raising operation of the knitting needle, the movement of the latch that jumps immediately after the latch comes out of the loop is regulated, and the latch does not close the hook. Can be.

According to another preferred aspect of the present invention, an outer cylinder is rotatably supported by the core rod, and a plurality of knitted needles arranged in the circumferential direction with respect to the core rod move up and down along the axial direction of the core rod. In a string-shaped circular knitting machine provided with a yarn guide for guiding the yarn supplied to the knitting needle that is supported and protrudes from the end of the outer cylinder and moves up and down. Immediately after coming out of the loop, within the range of rotation of the latch of the knitted needle (for example, the range of rotation B in the embodiment) and the hook of the knitted needle that is in the descending motion and the next thread is trying to lock onto the hook. The thread guide is positioned so that the guide hole is located on the extended line of the path along the circumscribed surface of the plurality of knitted needles connecting with the locking position (locking range) (for example, the locking range C in the embodiment). It is provided on the outer cylinder.
With this configuration, the thread itself supplied to the knitting needle is effectively used, and during the raising operation of the knitting needle, the movement of the latch that jumps immediately after the latch comes out of the loop is regulated, and the latch does not close the hook. Can be.

In another preferred aspect of the present invention, when the outer cylinder is viewed from the axial direction, the position of the guide hole of the yarn guide guide is at the top dead center position in the circumferential direction of the outer cylinder. 2 mm upward from the hook in the vertical direction of the hook of the knitted needle that is set in the range of 45 to 100 degrees from the position of the knitted needle toward the rotation direction of the outer cylinder, It is set in the range of 4 mm below.

Another preferred aspect of the present invention is a core rod (for example, core rod 5 in the embodiment) having a hollow cylindrical shape and having a plurality of guide grooves (for example, guide grooves 12 in the embodiment) along the longitudinal direction on the outer peripheral surface. ), A knitted needle (for example, the knitted needle 8 in the embodiment) accommodated in the guide grooves so as to be movable up and down, and two cylindrical cams (for example, in the embodiment) that impart reciprocating motion to the knitted needle. An upper cam 18 and a lower cam 17), and a cylindrical outer cylinder (for example, the outer cylinder 7 in the embodiment) that encloses the cam and rotates with the cam together with the cam. A space portion (for example, the space portion 39 in the embodiment) including the sliding portion of the cam crest (for example, the cam crest 18Y and the cam crest 17Y in the embodiment) that contacts the knitted needle of the cam inside the cam and the core. In front of the stick In each guide groove, the grease containing the solid lubricant is filled sealed.

In another preferred embodiment of the present invention, the solid lubricant is a lubricant selected from the group consisting of organic molybdenum, molybdenum disulfide, PTFE, aluminum oxide, zinc oxide, and cubic boron nitride.

According to the first and second aspects of the present invention, it is possible to prevent the latch from jumping up using the yarns that are sequentially supplied, and therefore, when the yarn guide guide is provided with another member to prevent the latch from jumping up. As compared with the above, it is possible to simplify the yarn guide and reduce the weight of the outer cylinder. Therefore, the rotation speed of the outer cylinder can be increased, and even if the string making speed depending on the rotation speed of the outer cylinder is increased, the generation of vibration can be suppressed and the productivity can be increased. In addition, since new yarns are sequentially supplied to prevent the latch from jumping up, there is no damage to the yarn, no separate member is required, and maintenance is required due to breakage of the latch compared to the case where another member is provided. In this respect, productivity can be improved.

According to the third aspect of the present invention, it is possible to prevent the latch from jumping up using the sequentially supplied yarns, so that compared with a case where another member is provided in the yarn guide guide to prevent the latch from jumping up. Thus, it is possible to simplify the yarn guide and reduce the weight of the outer cylinder. Therefore, the rotation speed of the outer cylinder can be increased, and even if the string making speed depending on the rotation speed of the outer cylinder is increased, the generation of vibration can be suppressed and the productivity can be increased. In addition, since new yarns are sequentially supplied to prevent the latch from jumping up, there is no damage to the yarn, no separate member is required, and maintenance is required due to breakage of the latch compared to the case where another member is provided. In this respect, productivity can be improved.

According to the fourth aspect of the present invention, the position of the guide hole of the yarn guide guide is set within the above-mentioned angle range, so that the latch of the rising knitting needle jumps immediately after it exits the loop. Since the thread can be arranged within the range, it is possible to reliably prevent the latch from jumping up and to position the thread that has exited the thread guide guide reliably around the outside of the knitting needle, The thread can be securely locked to the descending knitted needle.
By setting the position of the guide hole of the thread guide to the range of the dimensions described above, the thread can be securely locked to the descending knitted needle, and immediately after the rising knitted needle latch has exited the loop. Since the yarn can be arranged within the turning range of the latch that jumps up, the latch can be prevented from being flipped up reliably.

According to the fifth to tenth aspects of the present invention, even when the outer cylinder is knitted at a rotational speed exceeding 3000 min ⁻¹ , the wear of the parts constituting the circular knitting machine, in particular, the two cylindrical cams and the knitted needle is minimized. It is possible to reduce the frequency of maintenance such as replacement of parts and increase the productivity of the cylindrical braid.

It is a sectional side view of the circular knitting machine of this embodiment. It is a perspective view which shows the attitude | position change which a knitted needle moves up and down. It is a perspective view which shows the principal part of a circular knitting machine. It is the perspective view seen from the reverse direction to FIG. It is a perspective view which shows the state in which a thread | yarn is wound around a knitted needle. It is explanatory drawing which shows the relationship between the rotation range of a latch, and a thread | yarn. It is explanatory drawing which shows the relationship between the closed latch and a thread | yarn. It is a top view which shows typically the arrangement | positioning condition of a thread | yarn. It is an enlarged view of FIG. It is a perspective view of a core stick. It is a front view of a knitted needle. It is an enlarged view of the butt part of the knitted needle before abrasion. It is an enlarged view of the butt part of a knitted needle after wear. It is a side view of an upper cam and a lower cam. It is a figure which shows the structure of circular knitting.

Next, an embodiment of the present invention will be described with reference to the drawings. The string-like material knitted by the circular knitting machine of this embodiment is heat-treated by passing it through a heat-treating mold, and is subjected to sizing for reducing the outer diameter to a predetermined size to become a support body having no elasticity. Next, this sized support becomes a hollow fiber membrane in which a porous membrane layer is formed on the outside by applying a film-forming resin solution on the outer surface thereof. This hollow fiber membrane is modularized and used, for example, as a filtration membrane for water treatment. In addition, polyester fiber is mainly used for the raw material used as the material of the support, but the raw yarn knitted by this circular knitting machine is not limited to polyester fiber depending on the use, and various fibers can be knitted. is there.

FIG. 1 shows a circular knitting machine according to an embodiment of the present invention. The circular knitting machine 1 includes a plate-like base plate 2 fixed to a base. The base plate 2 has a fixing hole 3 fixed to the base on one end side, and an attachment hole 4 on the other end side. A hollow core rod 5 is fastened and fixed to the mounting hole 4 in a state in which the lower portion is prevented from loosening by two nuts 6 and 6. The core rod 5 protrudes from an upper end portion of an outer cylinder 7 to be described later, and functions as a rotation center axis of the outer cylinder 7. The core bar 5 has a function of guiding the string-like material knitted at the upper end portion downward through the hollow portion and a function of guiding a vertical movement of the knitted needle 8 described later. Here, in this embodiment, a size of 16 G is used for the knitted needle 8.

The core rod 5 includes a male screw portion 9 in which nuts 6 and 6 are screwed to the outer periphery of the lower portion, and a bearing mounting portion 11 for mounting the inner peripheral side of the bearing 10 on the upper outer periphery of the male screw portion 9. Twelve guide grooves 12 for setting the knitted needle 8 in the circumferential direction are formed in the circumferential direction on the upper outer circumference in a range from the outer cylinder 7 to the upper end protruding from the outer cylinder 7. Although the diameter of the groove bottom 13 of the guide groove 12 is 8 mm, a diameter of 3 mm or more to less than 12 mm can be used according to the diameter of the string-like material to be knitted. A total of twelve knitted needles 8 are arranged in the guide groove 12.

An inner race of the bearing 10 is fitted into the bearing mounting portion 11 of the core bar 5, and the bearing 10 is in a state where the end face is placed on the base plate 2. An outer cylinder 7 is rotatably mounted on the outer race of the bearing 10. Note that the rotation speed of the outer cylinder 7 is 3000 min ⁻¹ , and it is required that the outer cylinder 7 is excellent without stitch skipping even after 100 hours of continuous operation.
A large-diameter portion 14 having a larger diameter than the upper portion is formed in the lower portion of the outer cylinder 7. A belt groove 15 having a V-shaped cross section is formed on the outer periphery of the large-diameter portion 14, and a belt linked to a driving device (not shown) is stretched over the belt groove 15 to rotate the outer cylinder 7. Here, the lower end surface of the large-diameter portion 14 slightly enters the spot facing portion 16 formed by cutting the upper surface of the base plate 2.

In addition, as the bearing 10, it is preferable to use a double-row angular type bearing so that the upper part does not shake even at high speed rotation. Further, a toothed belt can be used instead of the belt V.

A lower cam 17 and an upper cam 18 are respectively fixed to the inner peripheral surface of the outer cylinder 7 by a lower screw 19 and an upper screw 20 screwed from the outer peripheral surface of the outer cylinder 7. A fixed gap is secured as a groove width between the lower edge of the upper cam 18 and the upper edge of the lower cam 17, and a guide groove 21 having an inner peripheral surface of the outer cylinder 7 as a groove bottom is formed in an elliptical shape. Has been. The guide groove 21 receives a butt portion 22 projecting in the direction in which the latch 28 opens and closes near the lower portion of the knitted needle 8. The unfolded shape of the guide groove 21 is a mountain shape, and each outer needle 8 arranged around the core bar 5 moves up and down as the outer cylinder 7 rotates. Here, the outer cylinder 7 is provided with a long hole 23, and the upper cam 18 is fixed with the upper screw 20 inserted through the long hole 23, and the upper screw 20 is loosened to form the lower tube 17. Further, the groove width (interval “H”) of the guide groove 21 can be adjusted.

At the upper end of the outer cylinder 7, an end plate 24 having the same diameter as the outer cylinder 7 and forming a part of the outer cylinder 7 is attached to the outer cylinder 7 with a fixing screw 29. In a state where the end plate 24 is attached to the outer cylinder 7, the upper end portion of the core bar 5 protrudes from the end plate 24. The end plate 24 includes a boss portion 30 that is inserted between the outer cylinder 7 and the core rod 5. The end plate 24 is provided with a stopper screw 25 that passes through the end plate 24 and positions the upper edge of the upper cam 18. The stopper screw 25 is provided with a lock screw 26 for fixing the position of the stopper screw 25. With the upper screw 20 temporarily fixed with the upper screw 20, the stopper screw 25 is screwed to the required position, and the stopper screw 25 is locked with the lock screw 26, and then the upper cam 18 is finally tightened with the upper screw 20. The position of the upper cam 18 is fixed.

The knitted needle 8 has a hook 27 at its upper end, and the hook 27 has a known structure that can be opened and closed by a latch 28. Twelve knitted needles 8 are arranged in the guide groove 12 with the hook 27 facing outward. These knitted needles 8 are sequentially raised and lowered along the guide groove 12 of the core bar 5 as the upper cam 18 and the lower cam 17 rotate together with the outer cylinder 7. Eleven knitted needles 8 protrude from the upper end surface of the core bar 5.

On the end plate 24, a thread-shaped guide guide 31 having a rod-like and simple and light structure for guiding the yarn supplied to the knitted needle 8 is fixed by screwing a lower screw portion 32 therein. In this embodiment, a yarn having a size of 420 dtex is used. At the upper end of the yarn guide 31, a guide hole 34 is formed which is inserted with a yarn from a bobbin (not shown) and is constituted by another member. A lock nut 35 is provided on the screw portion 32. Further, it is desirable to use ceramic as a material of the guide hole 34 in order to suppress wear.
Here, since the thread guide 31 also rotates together with the outer cylinder 7, the angle in the rotational direction to the knit needle 8 at the top dead center position with respect to the thread guide 31 does not change.
While the yarn is fed from the yarn guide 31 that rotates together with the outer cylinder 7, the yarn is supplied so as to be wound around the knitted needle 8 protruding from the core rod 5, and is locked to the hook 27 of the knitted needle 8 that moves up and down sequentially. Thus, a new loop 37 is formed under the core bar 5.

Here, FIG. 2 sequentially explains the state of the posture change in which the single knitting needle 8 moves up and down (schematic diagram showing the knitting operation by the circular knitting machine 1). Here, the single movement of the knitted needle 8 is developed on a plane so that it can be easily explained. Reference numerals (1), (2), and (3) show the knitting needle 8 being lowered by the upper cam 18, and reference numerals (5), (6), and (7) are the knitting needle 8 by the lower cam 17. Shows the rise.
Each knitted needle 8 is inserted with the previous loop 36 that constitutes the upper end of a string-like object (not shown). In the posture (1), with the latch 28 opened, the knitted needle 8 starts to descend with the hook 27 engaging the thread 40. In the posture (2), the knitted needle 8 is further lowered from the state in which the thread 40 is locked to the hook 27, and the posture is changed in the direction in which the latch 28 is closed by the previous loop 36. In the posture (3), the latch 28 immediately before coming out of the previous loop 36 completely closes the hook 27, and the locked thread 40 does not come out of the hook 27 and continues to descend.

In the posture (4), the hook 27 is pulled out from the previous loop 36 and the thread 40 is pulled out. In the posture (5), the knitted needle is now lifted to the outer peripheral side of the previous loop 36 in a state in which the knitting needle has left the previous loop 36. At this time, the thread 40 pulled out in the posture (5) becomes a new loop 37, and the new loop 37 starts to open the latch. In the posture (6), the latch 28 of the knitted needle 8 which is further raised is opened by the new loop 37, and in the posture (7), the knitted needle 8 is locked to the thread 40 to which the hook 27 is next sent out with the latch 28 opened. To do. Thereafter, the knitted needle 8 is lowered to the posture (1). Here, when the posture (6) is changed to the posture (7), the latch 28 operates to jump up immediately after the latch 28 is released from the new loop 37.

From the viewpoint of the knitting operation by the circular knitting machine 1, it can be explained as follows.
In the code (1), the thread 40 is hooked on the hook 27. In reference numerals (2) and (3), while the yarn 40 is pulled down, the latch 28 is closed by passing through the previously knitted existing loop 36, so that the hook 27 is not caught by the existing loop 36. Yes. At reference numeral (4), the knitted needle 8 comes out of the existing loop 36 downward. Next, as shown by reference numerals (5) and (6), when the knitted needle 8 is raised, the latch 28 is released by the thread 40 of the loop 37 that is being newly formed. 37 is formed. The circular knitting is continuously performed by repeating the above operation, and the cylindrical knitted string A is knitted.
The knitted cylindrical knitted string A passes through the hollow portion 5a (see FIGS. 1 and 2) of the core bar 5, is discharged below the circular knitting machine 1, and is taken up by a take-up machine (not shown).

The posture of one knitted needle 8 shown in FIG. 2 is the posture of each knitted needle 8 at a certain point in time as shown in FIGS. Here, FIGS. 3 and 4 are perspective views of the main part of the circular knitting machine as seen from different directions, and the loops already knitted are not shown for convenience of illustration. As shown in FIGS. 3 and 4, when an outer cylinder (not shown) rotates counterclockwise, the core rod 5 does not rotate and the thread guide guide rotates counterclockwise. In FIG. 3, the knitting needle 8 (a) that rises with the amount of protrusion gradually decreasing from the knitting needle 8 (a) at the top dead center to the knitting needle 8 (b) at the bottom dead center counterclockwise. Is located, and the protrusion amount gradually decreases from the knitted needle 8 (a) at the top dead center to the knitted needle 8 (b) at the bottom dead center in a clockwise direction. 8 is located.

Here, the thread 40 from the bobbin supplied from the guide hole 34 of the thread guide 31 has a second position in the counterclockwise direction from the knitted needle 8 (a) at the top dead center position. Each of the knitting needles 8 within a range where the hook 27 of the fourth knitting needle 8 (d) is connected clockwise from the knitting needle 8 (a) at the top dead center position. It is routed so as to wrap around. 3 and 4, the posture number of the knitted needle 8 described in FIG. 2 is also described.

FIG. 5 shows a passage path of the thread 40 that is arranged so as to be wound around the plurality of knitting needles 8. Here, in FIG. 5, only the knitted needle 8 on the near side is shown.
In the elevating knitted needle 8 (c), which is in the second position counterclockwise from the top dead center knitted needle 8 (a), the thread 40 is the height of the base portion of the latch 28 and contacts the knitted needle 8. The previous loop 36 is just before coming out of the latch.
In the elevating knitted needle 8 (e), which is in the first position counterclockwise from the top dead center knitted needle 8 (a), the thread 40 is below the base portion of the latch 28 and is connected to the knitted needle 8. Passing through the contacted position, the previous loop 36 is immediately after the latch 28 is removed.
At the top dead center knitted needle 8 (a), the thread 40 passes through a position in contact with the vicinity of the central portion in the vertical direction of the latch 28, and the previous loop 36 is completely removed from the latch 28.

In the descending knitted needle 8 (f) which is in the first position clockwise from the top dead center knitted needle 8 (a), the thread 40 passes through the position in contact with the vicinity of the central portion of the latch 28 in the vertical direction. The loop 36 is approaching from the latch 28.
In the descending knitted needle 8 (g) that is in the second position clockwise from the top dead center knitted needle 8 (a), the thread 40 passes through the position in contact with the vicinity of the central portion in the vertical direction of the latch 28, and the previous time. The latch 28 reaches the loop 36.
In the descending knitted needle 8 (h) which is in the third position clockwise from the top dead center knitted needle 8 (a), the thread 40 passes through the position in contact with the base portion of the latch 28, and the previous time The loop 28 rotates the latch 28 in a direction to close the hook 27.
In the descending knitted needle 8 (d) at the fourth position clockwise from the top dead center knitted needle 8 (a), the thread 40 is engaged with the hook 27 of the latch 28, and the previous loop 36 A latch 28 completely closes the hook 27.

That is, when the passing position of the thread 40 is specified at the position where the thread guide guide 31 is attached, the position within the rotation range of the latch 28 of the knitted needle 8 (e) immediately after the latch 28 is removed from the previous loop 36 during the ascending operation. A plurality of knitting needles within a range connecting the hook 27 of the knitting needle 8 (d) positioned at the upper end of the core bar 5 to be closed and further lowered to the position where the hook 27 is locked to the thread. The yarn guide guide 31 is attached to the outer cylinder 7 so that the guide hole 34 of the yarn guide guide 31 is located on the extended line of the path along the circumscribed surface of 8, 8, 8.

Here, the position through which the thread 40 passes is outside the knitted needle 8 arranged so that the thread 40 is wound as shown in FIG. 5, but the range through which the thread 40 passes is shown in FIG. Is set within the rotation range B at the base of the tip of the latch 28. That is, the yarn 40 supplied from the guide hole 34 of the yarn guide 31 is effectively used to form a new loop 37, and immediately after the latch 28 of the knitted needle 8 is removed from the previous loop 36 during the ascending operation. The latch 28 is prevented from jumping up.

In particular, in FIG. 5, when the loop 36 just before coming out of the latch 28 of the knitted needle 8 (c) is pulled down from the latch 28 of the knitted needle 8 (e), the latch 28 jumps up. As shown in FIG. 6, the jumping-up is prevented by the thread 40 (OK) that is located within the rotation range B of the latch 28 and obstructs the rotation. Therefore, the thread 40 (NG) outside the rotation range B of the latch 28 cannot prevent jumping, and the latch 28 closes the hook 27 as shown in FIG. Is lowered, the hook 27 cannot be locked to the thread 40 (NG).

FIG. 8 is a view of the outer cylinder 7 and the core rod 5 as viewed from the upper side in the axial direction, and FIG. 9 is an enlarged view of a main part of FIG.
In FIG. 8, the position of the guide hole 34 of the thread guide 31 in the circumferential direction of the outer cylinder 7 is counterclockwise (rotational direction) of the outer cylinder 7 from the position of the knitted needle 8 (a) at the top dead center position. The guide hole 34 of the yarn guide 31 is set in the range of angle θ (45 ° to 100 °) toward the upper end of the hook 27 of the knitted needle 8 (a) at the top dead center position. The vertical dimension K is set within the range of 2 mm (2 mm upward) to −4 mm (4 mm downward) from the hook 27. The distance L between the position of the guide hole 34 and the tangent to the core bar 5 on the line connecting the position of the guide hole 34 of the thread guide 31 and the axis of the core bar 5 is set to 5 mm to 8 mm. Yes. This value varies depending on the length of the latch 28.

Here, the range of the angle θ is more preferably set to 45 degrees to 100 degrees. In the current circular knitting machine described so far, θ = 90 degrees, K = 2 mm, and L = 8 mm are set.
By setting in this way, the jumping of the latch 28 that has escaped from the previous loop 36 is prevented by the yarn 40 itself, and the next yarn 40 can be reliably locked by the knitted needle 8.

The numerical range as described above is set because when the θ is out of the above range, the yarn is out of the rotation range B of the latch 28 in FIG. If the angle θ is outside the above range, the passing position of the yarn 40 immediately after exiting the yarn guide guide 31 is on the inner side of the diameter of the guide groove 12 of the core rod 5. When the thread 40 passes through the back surface of the knitted needle 8 that is raised downward, and then descends, the thread 40 cannot be locked to the hook 27.

Further, if the vertical dimension K with respect to the upper end of the hook 27 is out of the above range, the thread 40 passes through a place higher than the knitted needle 8, and the hook 27 cannot be locked to the thread 40. If the dimension K deviates from the above range, the latch 28 shown in FIG. 6 deviates from the rotation range B, and the effect of preventing the latch 28 from jumping up cannot be exhibited.
When the distance L deviates from the above range, the diameter of the outer cylinder 7 increases, and the outer cylinder 7 expands, which is disadvantageous for high-speed rotation. When the distance L deviates from the above range, the yarn guide The guide 31 itself contacts the latch 28.

According to the above-described embodiment, the latch 28 can be prevented from jumping up immediately after exiting the previous loop 36 using the yarns 40 that are sequentially supplied, so that the yarn guide guide 31 is provided with the yarn guide guide 31 to prevent the latch 28 from jumping up. Compared with the case where another member is provided, the yarn guide 31 can be simplified and the outer cylinder 7 can be reduced in weight. Therefore, the rotation speed of the outer cylinder 7 can be increased (for example, 3000 to 4000 min ⁻¹ ), the dynamic balance of the outer cylinder 7 is improved, and the string making speed depending on the rotation speed of the outer cylinder 7 is increased. Can also suppress the generation of vibrations and increase productivity.
Further, since new yarns 40 for preventing the latch 28 from jumping up are sequentially supplied, the yarn 40 is not damaged and the knitting needle 8 is not damaged. Further, there is no need for a separate member for preventing the latch 28 from being flipped up, and there is no need for maintenance due to breakage of the latch 28 as compared with the case where this separate member is provided, and productivity can be improved in that respect.

In particular, when the position of the guide hole 34 of the thread guide 31 is set within the specific angle range described above with reference to the position of the knitting needle 8 (a) at the top dead center position, the knitting needle 8 that rises. The thread 40 can be arranged within the rotation range B of the latch 28 that jumps up immediately after the latch 28 has exited the previous loop 36. Therefore, the latch 28 can be reliably prevented from jumping up, and the yarn 40 that has exited the yarn guide guide 31 can be positioned so as to be surely wound around the outside of the knitted needle 8. Thus, the thread 40 can be reliably locked.
By setting the position of the guide hole 34 of the thread guide 31 to the range of the vertical dimension of the hook 27 of the knitting needle 8 (a) at the top dead center position, the thread 40 can be securely attached to the descending knitting needle 8. Further, the thread 40 can be disposed in the rotation range B of the latch 28 that jumps immediately after the latch 28 of the rising knitted needle 8 exits the previous loop 36, so that the latch 28 Bounce-up can be surely prevented.

In addition, this invention is not restricted to the said embodiment, The angular bearing was used as the bearing 10, However, The structure which arrange | positions a single row bearing up and down is also employable. Further, the arrangement number, size, thread thickness, and the like of the knitted needle 8 are merely examples, and the present invention can also be applied to arrangement numbers, sizes, and thread thicknesses other than this embodiment.

As shown in FIG. 10, the core rod 5 is a cylindrical member having a hollow portion 5a through which the cylindrical braid A passes downward, and the upper end portion and the lower end portion are formed to have a slightly smaller diameter. Yes. A male threaded portion 9 in which nuts 6 and 6 are screwed onto the outer periphery of the lower end portion of the core bar 5 and a bearing mounting portion 11 for mounting the inner peripheral side of the bearing 10 on the upper outer periphery of the male threaded portion 9 are provided. Six guide grooves 12 for setting the knitted needle 8 in the circumferential direction are formed on the upper outer periphery of the bearing mounting portion 11 in the circumferential direction in a range from the outer cylinder 7 to the upper end portion protruding from the outer cylinder 7. A total of six knitted needles 8 are arranged in the guide groove 12. The diameter d of the groove bottom 13 of the guide groove 12 (hereinafter referred to as the bottom circumferential diameter d) is set according to the outer diameter of the cylindrical braid A. In this embodiment, the outer diameter of the cylindrical braid A is preferably in the range of 3 to 14 mm, more preferably 6 to 12 mm.

As shown in FIG. 11, the knitted needle 8 has a hook 27 at its upper end, and the hook 27 has a known structure that can be opened and closed by a latch 28. A butt portion 22 is formed in the vicinity of the lower portion of the knitted needle 8 so as to protrude in the direction in which the latch 28 opens and closes. The knitted needle 8 is a thin plate material of about 0.5 mm, and the material is generally carbon tool steel, and the surface hardness after heat treatment is generally HRC 60 or more. Here, the HRC measurement method is based on JIS Z 2245: 2005.
The sizes of the hook 27 and the latch 28 are generally represented by a gauge “G”, and are appropriately selected depending on the fineness of the yarn 40 to be knitted. In this embodiment, 16G is preferable. The number of knitting needles 8 is preferably 5 to 16, more preferably 8 to 12, although it depends on the degree of opening of the knitted string A of the cylindrical knitted string A. In this embodiment, the case where the number of guide grooves 12 of the core rod 5 shown in FIG. In this case, the outer diameter of the cylindrical braid A obtained by combining the bottom circumferential diameter d of the core bar 5 and the number of the knitted needles 8 is about 3 to 8 mm.
These knitted needles 8 are arranged in the guide groove 12 with the hooks 27 facing outward, and an upper cam 18 and a lower cam 17 (to be described later) rotate together with the outer cylinder 7 so that the butt portion 22 and the upper cam 18 are moved downward. It latches between the cams 17 and rises and descends in order along the guide grooves 12 of the core bar 5.

As shown in FIG. 13, a lower cam 17 and an upper cam 18 are respectively fixed to the inner peripheral surface of the outer cylinder 7. Both the lower cam 17 and the upper cam 18 are formed in a cylindrical shape, and the upper end of the lower cam 17 and the lower end of the upper cam 18 are inclined surfaces with a predetermined angle α with respect to the axis of the core rod 5. The upper cam 18 and the lower cam 17 face each other and are arranged vertically with the butt portion 22 of the knitted needle 8 interposed therebetween, and a vertical interval “slightly larger than the height“ h ”of the butt portion 22 shown in FIG. H ″ is kept constant, and is fixed inside the cylinder of the outer cylinder 7 by a lower screw 19 and an upper screw 20 which are screwed from the outer peripheral surface of the outer cylinder 7. Here, the inclined surface of the lower cam 17 is cut in the reverse direction on the upper end side, and the inclined surface of the upper cam 18 is cut in the reverse direction on the lower end side.
Therefore, between the lower edge of the upper cam 18 and the upper edge of the lower cam 17, a guide groove 21 having an inner peripheral surface of the outer cylinder 7 as a groove bottom is formed in an elliptical shape. Part 22 is accepted. Here, the outer cylinder 7 is provided with a long hole 23, and the upper cam 18 is fixed with the upper screw 20 inserted through the long hole 23, and the upper screw 20 is loosened to form the lower tube 17. The distance “H” between the guide grooves 21 can be adjusted.
The angle α is determined by the bottom circumferential diameter d and the vertical movement stroke of the knitted needle 8. When the vertical movement stroke of the knitted needle 8 is the same, the angle α decreases and the inclined surface becomes steep when the bottom circumferential diameter d decreases. Conversely, as the bottom circumferential diameter d increases, the angle α increases and the inclined surface becomes gentler.

At the upper end of the outer cylinder 7, an end plate 24 having the same diameter as the outer cylinder 7 and forming a part of the outer cylinder 7 is attached to the outer cylinder 7 with a fixing screw 29. In a state where the end plate 24 is attached to the outer cylinder 7, the upper end portion of the core bar 5 protrudes from the end plate 24. The end plate 24 includes a boss portion 30 that is inserted between the outer cylinder 7 and the core rod 5. The end plate 24 is provided with a stopper screw 25 that passes through the end plate 24 and positions the upper edge of the upper cam 18. The stopper screw 25 is provided with a lock screw 26 for fixing the position of the stopper screw 25. With the upper screw 20 temporarily fixed with the upper screw 20, the stopper screw 25 is screwed to the required position, and the stopper screw 25 is locked with the lock screw 26, and then the upper cam 18 is finally tightened with the upper screw 20. The position of the upper cam 18 is fixed.

Accordingly, the upper cam 18 and the lower cam 17 are rotated along with the rotation of the outer cylinder 7, and the butt portion 22 of the knitted needle 8 is raised along the cam crest 17 </ b> Y of the lower cam 17. The butt portion 22 of the knitted needle 8 that has reached the apex of the lower cam 17 is then lowered along the cam crest 18Y of the upper cam 18, so that the knitted needle 8 is lowered. By repeating the above movement, the plurality of knitted needles 8 arranged on the circumference of the core bar 5 sequentially reciprocate.
When the supplied thread 40 is loosened, the thread 40 is detached from the hook 27 of the knitting needle 8 and becomes entangled with the knitting needle 8. Therefore, a tensioner (not shown) is provided upstream so as to apply a constant tension to the thread 40. The member which provides tension | tensile_strength etc. is provided.

On the end plate 24, a rod-shaped, simple and light-weight thread guide 31 for guiding the thread 40 supplied to the knitting needle 8 is fixed by screwing a lower thread portion 32 therein. At the upper end of the yarn guide 31, a guide hole 34 is provided which is inserted with a yarn 40 from a bobbin (not shown) and is constituted by another member. A lock nut 35 is provided on the screw portion 32. Further, it is preferable to use ceramic as the material of the guide hole 34 in order to suppress wear with the yarn 40 moving at high speed. This is because if the yarn 40 is worn by friction, it may cause yarn breakage or yarn feathers.
Here, since the thread guide 31 also rotates together with the outer cylinder 7, the angle in the rotational direction to the knit needle 8 at the top dead center position with respect to the thread guide 31 does not change.
While the yarn 40 is fed from the yarn guide 31 that rotates together with the outer cylinder 7, the yarn 40 is supplied so as to wrap around the knitted needle 8 protruding from the core bar 5, and is sequentially applied to the hook 27 of the knitted needle 8 that moves up and down. A new loop 37 is formed toward the bottom of the core bar 5 by being locked.

Next, the operation of this embodiment will be described.
The circular knitting performed by the circular knitting machine 1 is knitting a cylindrical horizontal knitted fabric.
As shown in FIG. 14, the horizontal knitted fabric is obtained by spirally forming a curved loop 37 and continuously connecting each loop 37 to the previous loop 36. A stitch 38 is provided in 36.

As the speed of knitting the cylindrical knitted string A (take-up speed) increases, the rotational speed of the outer cylinder 7 of the circular knitting machine 1 also increases accordingly. The rotational speed varies slightly depending on the number of the knitting needles 8, the bottom circumferential diameter d of the core bar 5, the size of the stitch 38, and the like, but when it is carried out within the preferred range of the present invention, the take-up speed is 1.7 m / At min, the rotational speed is about 1800-2200 min ⁻¹ . Further, when the take-up speed is 3.4 m / min, the rotational speed is about 3000 to 3500 min ⁻¹ . Further, when the take-up speed is 4.5 m / min, the rotation speed is about 4000 to 4500 min ⁻¹ .

When the knitting needle 8 is raised or lowered along the cam crest 18Y and the cam crest 17Y of the upper cam 18, the lower cam 17, the sliding portions of the cam crest 18Y, the cam crest 17Y and the butt portion 22 of the knitting needle 8 are Friction occurs due to the contact between metals, and wear occurs in each sliding portion due to long-time operation. As shown in FIG. 12B, since the thread 40 is pulled down when the knitted needle 8 is lowered, the tension of the thread 40 is also applied, and the friction between the upper cam 18 and the butt part 22 becomes larger. The upper wear amount h1 tends to be larger than the lower wear amount h2. Further, in high-speed operation, in addition to the wear of the butt portion 22, the wear of the cam crest 18Y and the cam crest 17Y also progresses rapidly, and the durability (use limit) of the parts is significantly reduced.

In particular, the surface hardness of the cam crest 18Y and the cam crest 17Y greatly affects the wear. When a cam with a cam peak surface hardness of HRC50 or less is used for continuous operation at a rotational speed of 3000 min ^-1 or more, significant wear occurs at the butt portion 22, cam peak 18 Y, and cam peak 17 Y after an operation time of 300 to 400 hours. In the worst case, the butt portion 22 breaks down, causing serious damage to the inside of the circular knitting machine 1 rotating at high speed.

Even when the surface hardness of the cam crest is equal to or higher than HRC 61, particularly greater than the hardness of the knitted needle 8, the wear of the butt portion 22 is likely to proceed, and the frequency of replacing the knitted needle 8 increases, leading to a decrease in productivity. . As a result of intensive studies by the present inventors, the surface hardness of the cam crest is preferably HRC51 or more, more preferably in the range of HRC55-60. As a result of continuous operation at a rotational speed of about 2000 min ⁻¹ using a cam in this range, the knitted needle 8, cam cam 18Y, and cam cam 17Y are hardly worn even during an operation time of 1000 hours, and sufficient durability is achieved. It turns out that there is sex. Similarly, as a result of continuous operation at a rotational speed of about 3500 min ⁻¹ , slight wear was observed on the knitted needle 8 even during an operation time of 500 hours, but almost no wear occurred on the cam peaks 18Y and 17Y. It was not found that it was sufficiently durable.

Examples of the method for bringing the surface hardness of the cam ridge into the above-described range include heat treatment such as quenching, or coating treatment such as DLC coating and TiN coating, and it is more preferable to perform the heat treatment.
As the material of the cam, steel is used when heat treatment is performed, but carbon steel for machine structure, various tool steels, and the like can be used to obtain the above-described surface hardness. The material used for the coating treatment is not limited to steel, and various metals can be used. Examples of the heat treatment include carburizing and quenching, nitriding, induction hardening, and the like.
Similarly, the plurality of slit-shaped guide grooves 12 of the core rod 5 are likely to be worn by friction because the knitted needle 8 reciprocates. In particular, the knitted cylindrical knitted string A is pulled downward through the hollow portion 5a at the tip corner of the guide groove 12, so that the knitted needle 8 arranged on the circumference is loaded toward the center. Therefore, it is easy to wear.
Therefore, it is preferable to improve the durability of the surface of the core bar 5 and the guide groove 12 by the same surface treatment as the cam crest 18Y and the cam crest 17Y.
Also, the angle α shown in FIG. 13 affects the wear. When the angle α is small, that is, when the inclined surface is steep, the frictional resistance between the butt portion 22 and the cam crest 18Y and the cam crest 17Y increases, so that the wear easily proceeds. Therefore, the angle α is determined by the bottom circumferential diameter d and the vertical movement stroke of the knitted needle 8, but it is desirable to make it as large as possible.

Further, the sliding portions of the cam crest 18Y, the cam crest 17Y and the sliding portion of the butt portion 22 of the knitted needle 8 and the sliding portion in which the knitted needle 8 inserted in the plurality of slit-shaped guide grooves 12 of the core rod 5 reciprocates. In general, grease is used for lubrication, but the amount of grease applied and the consistency (consistency) indicating the hardness of the grease (corresponding to the kinematic viscosity of the lubricating oil) are also important for wear control.
In particular, when a small amount of grease is applied to the sliding portions of the knitting needle 8, the upper cam 18, and the lower cam 17, the grease present in the space 39 (see FIG. 1) formed between the outer cylinder 7 and the core rod 5. Is moved to the inner wall of the outer cylinder 7 due to centrifugal force during high-speed operation, and the sliding portions of the knitted needle 8, the upper cam 18, and the lower cam 17 tend to be insufficiently lubricated, and the progress of wear is accelerated. On the other hand, when the grease is sufficiently sealed so as to fill the space 39, the grease is difficult to move on the inner wall of the outer cylinder 7 by centrifugal force even at high speed operation, and the knitted needle 8, the upper cam 18, and the lower cam Sufficient lubrication can be obtained for the sliding portion 17, and wear of the butt portion 22 of the knitting needle 8, the cam crest 18 </ b> Y, and the cam crest 17 </ b> Y can be suppressed.
Further, the grease becomes soft (viscosity decreases) due to heat generated by friction of the sliding portion. When the grease becomes soft, it moves to the inner wall of the outer cylinder 7 due to the centrifugal force during high-speed operation as described above, and the sliding portions of the knitted needle 8, the upper cam 18, and the lower cam 17 are likely to be insufficiently lubricated. Progresses faster. However, if hard grease with a high consistency is used, the resistance of the grease imposes a load on each part of the knitting machine and the drive motor, thereby shortening the life of the apparatus. Accordingly, the hardness of the grease is also an important factor for suppressing wear.
The hardness of the grease is represented by an NLGI (National Lubricating Grease Institute) consistency number described in JISK2220. The larger the number, the harder the grease. As the grease of the present invention, it is preferable to use a grease having an NLGI consistency number “No. 1” to “No. 2”, and an NLGI consistency range of 265 to 295 (1/10 / mm) is used. It is more preferable to use grease having a consistency number of “No. 2”.

By using organic molybdenum grease containing solid lubricant, molybdenum disulfide grease, fluorine-based grease, PTFE-containing grease, aluminum oxide, zinc oxide, ceramic grease containing ultrafine particles such as cubic boron nitride, etc. It is preferable to use it during high-speed operation because a low-friction lubricating coating is formed on the sliding surface to prevent metal contact and reduce wear and seizure.

According to the above embodiment, even if the outer cylinder is knitted at a rotational speed exceeding 3000 min ⁻¹ , the wear of the parts constituting the circular knitting machine 1, particularly the upper cam 18, the lower cam 17 and the knitted needle 8, is suppressed as much as possible. Thus, the frequency of maintenance such as replacement of parts can be reduced, and the productivity of the cylindrical braided string A can be increased.
Further, since the cam crest 18Y and the cam crest 17Y of the upper cam 18 and the lower cam 17 are hardened, the cost can be reduced as compared with the case where the hardness of the entire upper cam 18 and the lower cam 17 is increased. it can.

Next, embodiments of the present invention will be described in detail by the following examples.
(Measurement of knitting needle wear)
The amount of wear of the butt portion 22 of the knitted needle 8 is determined by removing the knitted needle 8 from the circular knitting machine 1 after operation, and observing the butt portion 22 with a stereomicroscope, as shown in FIG. The amount of wear h2 was measured with a scale (ruler).

Example 1
A cylindrical knitted string A was produced using the circular knitting machine 1 shown in FIG.
As the yarn 40, a polyester fiber (fineness: 420 dtex, number of filaments: 180) was used. As the circular knitting machine 1, a table-type string knitting machine (manufactured by Sakurai Textile Machinery Co., Ltd., the number of knitting needles: 12, knitting needle size: 16G, the bottom circumferential diameter d of the core bar: 8 mm, cam hardness: HRC55) is used. It was. For the lubricant, Sumitomo Lubricant Co., Ltd. organic molybdenum grease (trade name: Mori FM-L grease (No. 2 consistency number)) inside the outer cylinder 7, a knitted needle 8, a core rod 5, The space portion 39 (see FIG. 1) where the sliding portions of the upper cam 18 and the lower cam 17 are provided is sufficiently filled and sealed. The take-up speed of the take-up machine was 1.94 m / min. At this time, the rotational speed of the circular knitting machine 1 was about 2000 min ⁻¹ . When the operation was continued until the yarn 40 wound around the supply bobbin disappeared, the operation time was about 100 hours. Immediately after the stop, the operation was continued using the new yarn 40, and a continuous operation was performed for a total of 3000 hours.

When the bat portion 22 of all the knitted needles 8 was observed with a stereomicroscope after the operation was completed, the average value of the wear amount of the upper wear amount h1 and the lower wear amount h2 was about 0.35 mm. It was about 12% of the height h. Further, when the cam crest 18Y and the cam crest 17Y that are the sliding portions of the upper cam 18 and the lower cam 17 with the knitted needle 8 were observed, no wear was confirmed.

(Example 2)
A cylindrical knitted string A was produced under the same conditions as in Example 1 except that the take-up speed of the take-up machine was 3.4 m / min.
At this time, the rotational speed of the circular knitting machine 1 was about 3500 min ⁻¹ . When the operation was continued until the yarn 40 wound around the supply bobbin disappeared, the operation time was about 50 hours. Immediately after the stop, the operation was continued using the new yarn 40, and a continuous operation was performed for a total of 500 hours.
When the bat portion 22 of all the knitted needles 8 was observed with a stereomicroscope after the operation was completed, the average value of the wear amount of the upper wear amount h1 and the lower wear amount h2 was about 0.41 mm. It was about 14% of the height h. Further, when the cam crest 18Y and the cam crest 17Y that are the sliding portions of the upper cam 18 and the lower cam 17 with the knitted needle 6 were observed, no wear was confirmed.

(Example 3)
A cylindrical knitted string A was produced under the same conditions as in Example 1 except that the take-up speed of the take-up machine was 4.5 m / min.
At this time, the rotational speed of the circular knitting machine 1 was about 4500 min ⁻¹ . When continuously operating until the yarn 40 wound around the supply bobbin disappeared, the operation time was about 38 hours. Immediately after the stop, the operation was continued using the new yarn 40, and a continuous operation was performed for a total of 265 hours.
When the butt portion 22 of all the knitted needles 8 was observed with a stereomicroscope after the operation was completed, the average value of the wear amount of the upper wear amount h1 and the lower wear amount h2 was about 0.46 mm. It was about 15% of the height h. Further, when the cam crest 18Y and the cam crest 17Y that are the sliding portions of the upper cam 18 and the lower cam 17 with the knitted needle 6 were observed, no wear was confirmed.

(Comparative Example 1)
A cylindrical knitted string A was produced under the same conditions as in Example 1 except that the filling amount of the lubricant was about 1/5 of that in Example 1.
At this time, the rotational speed of the circular knitting machine 1 was about 2000 min ⁻¹ . When the operation time was about 320 hours, the noise was generated from the circular knitting machine 1, so the operation was stopped.
When the butt portion 22 of all the knitted needles 8 was observed with a stereomicroscope, the average value of the wear amount of the upper wear amount h1 and the lower wear amount h2 was about 1.5 mm, and the height h of the butt portion 22 was About 50%.

(Comparative Example 2)
Cylindrical knitted string A was produced under the same conditions as in Example 2 except that general lithium grease (No. 2 consistency) was used as the lubricant.
At this time, the rotational speed of the circular knitting machine 1 was about 3500 min ⁻¹ . When the operation was continued until the yarn 40 wound around the supply bobbin disappeared, the operation time was about 50 hours. Immediately after the stop, the operation was continued using the new yarn 40, and a continuous operation was performed for a total of 500 hours.
When the bat portion 22 of all the knitted needles 8 was observed with a stereomicroscope after the operation was completed, the average value of the wear amount of the upper wear amount h1 and the lower wear amount h2 was about 1.4 mm. It was about 45% of the height h.

Since the circular knitting machine of the present invention can effectively prevent latch jumping, it can be suitably used, for example, for manufacturing string-like objects.

DESCRIPTION OF SYMBOLS 1 Circular knitting machine 5 Core rod 7 Outer cylinder 8 Knitted needle 12 Guide groove 18 Upper cam 17 Lower cam 18Y Cam mountain 17Y Cam mountain 28 Latch 27 Hook 39 Space part 40 Yarn 36 Loop 34 Guide hole d Bottom circumference diameter A Cylindrical shape Braided string B rotation range

Claims (11)

1. A plurality of knitting needles having a latch, which are arranged in the circumferential direction of the hollow core rod, are supported so as to be reciprocable along the axial direction of the core rod, and a guide for guiding a thread to be supplied to the knitting needle is the core. A knitting machine provided to rotate about a rod as a central axis,
   A knitting machine in which the guide is disposed at a position where the yarn is routed within a rotation range of the latch of the knitted needle immediately after the latch of the knitted needle is released from the loop knitted previously.
2. A plurality of knitted needles arranged in the circumferential direction of the hollow core rod are supported so as to be able to reciprocate along the axial direction of the core rod, and a guide for guiding a thread to be supplied to the knitted needle is centered on the core rod. A knitting machine provided to rotate,
   A knitting machine having a latch presser portion for the yarn between the guide and a position where a hook of a knitted needle is engaged with the yarn.
3. An outer cylinder is rotatably supported by the core rod, and a plurality of knitted needles arranged in a circumferential direction with respect to the core rod are supported to be vertically movable along the axial direction of the core rod, and an end portion of the outer cylinder A string-shaped circular knitting machine provided with a yarn guide for guiding the yarn supplied to the knit needle that protrudes and moves up and down,
   The range of rotation of the latch of the knitted needle immediately after the latch comes out of the loop during the ascending operation, and the locking position of the hook of the knitted needle that is in the descending operation and the next thread tries to lock on the hook. A knitting machine in which the yarn guide guide is provided in an outer cylinder so that a guide hole is positioned on an extension line of a path along a circumscribed surface of a knitted needle that connects the knitted needles.
4. In the circumferential direction of the core rod, the position of the guide is set in a range of 45 degrees to 100 degrees from the position of the knitted needle at the top dead center position toward the rotation direction of the guide, and the top dead center position 4. The knitting machine according to claim 3, wherein in the vertical direction of the hook of the knitted needle, the knitting machine is set within a range of 2 mm upward and 4 mm downward from the hook.
5. The knitting machine according to any one of claims 1 to 4, wherein the number of knitting needles is in the range of 5 to 16.
6. The knitting machine according to claim 5, wherein the circumferential diameter of the bottom of the guide groove is in the range of 3 to 14 mm.
7. The knitting machine according to claim 6, wherein the outer diameter of the knitted fabric to be knitted is in the range of 3 to 8 mm.
8. The knitting machine according to claim 7, wherein a knitted cylindrical braid used for the support for the hollow porous membrane is knitted.
9. The knitting machine according to claim 8, wherein a rotation speed of the outer cylinder is set in a range of 1800 to 4500 min- ¹ .
10. A plurality of guide grooves are provided in the longitudinal direction of the outer peripheral surface of the core bar so that the knitted needle is supported so as to be movable up and down along the axial direction of the core bar, and the knitted needle is moved up and down inside the outer cylinder. Two cylindrical cams to be applied are arranged, and a solid lubricant is contained in the space portion in the outer cylinder including the sliding portion of the cam crest where the cam and the knitted needle abut and each guide groove. The knitting machine according to any one of claims 3 to 9, wherein grease is filled and enclosed.
11. The knitting machine according to claim 10, wherein the solid lubricant is selected from the group consisting of organic molybdenum, molybdenum disulfide, PTFE, aluminum oxide, zinc oxide, and cubic boron nitride.

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