EP3690095B1 - Knitting machine needle and knitting system - Google Patents

Description

The present invention relates to a knitting machine needle and a knitting system. Knitting machine needles are known in many different designs. Knitting machine needles are inserted into a knitting machine and often moved over one or more butts of the knitting machine needle in a channel of a needle bed of the knitting machine. For this purpose, the butt of the knitting machine needle interacts with a lock on the knitting machine. In the case of high-speed knitting machines in particular, the knitting machine needle is subjected to strong accelerations. Knitting machine needles that have a latch are often used ("latch needles"). The tongue performs numerous rapid pivoting movements that serve to form stitches together with a hook. The high dynamics of this pivoting movement can lead to errors in stitch formation on high-speed knitting machines. Such failures are favored by the inevitable wear and tear on the hook and tongue. The hook and the latch are arranged at a front end of the knitting machine needle and connected to the butt of the knitting machine needle via a shank.

In some types of knitting machines, collisions occur between the butt of the knitting needle and the cams or selection parts. In order to counteract the development of damage or at least to mitigate it, the JP62191888U and the EP1424416A1 proposed to apply predetermined breaking points to the foot of knitting machine needles so that the foot breaks off before major damage occurs. A similar predetermined breaking point is also shown in CN2534208Y . In addition, the in the CN2534208Y The illustrated needle has a groove in the underside of the needle shaft below the position of the latch return. Such a groove serves to relieve the strain on the stitch when the stitch slides over the tongue which is in the reverse position. This strain relief occurs when the existing fabric (preferably the previous stitch) engages in this groove. Such throats for strain relief are in many designs of knitting machine needles below or in the immediate vicinity of the to find the tongue-retraction position. These grooves are not predetermined breaking points, since the grooves are not intended to be broken with any appreciable probability by the force that the yarn exerts on the hook.

the DE1635837A1 shows a needle equipped with sections on the shank designed to prevent the transmission of shock waves from the foot to the hook. These sections can be designed as sections with modified mechanical properties or as sections with a reduction in the cross section of the needle. In each exemplary embodiment, the special sections are implemented at points on the shaft where the shaft has its greatest height. It is therefore not a question of predetermined breaking points, since the shaft is not very likely to break at these points.

the DE4320956A1 and the DE19503048C2 show predetermined breaking points on sewing or embroidery needles.

Recently, especially long, slender knitting machine needles have suffered damage from collisions between the butts of adjacent areas of the shank and the cams. the DE3311361 A1 shows a knitting system with such long, slender knitting machine needles.

It is the object of the present invention to remedy this problem.

The object is achieved by a knitting machine needle according to claim 1 and a knitting system according to claim 13.

The knitting machine needle according to the invention comprises a hook for the formation of stitches, which delimits the shank in the longitudinal direction of the shank, or starts there, and which ends in a hook point. In the longitudinal direction of the shank, the hook is followed by a first drive section. The force for moving the knitting machine needle is transmitted from a cam part of the knitting machine to the drive section of the knitting machine needle. The drive section can be designed as a foot that protrudes beyond the shaft in the positive vertical direction of the shaft. The drive section can be formed by a coupling point. In this case, a coupling element usually has a foot and the force for moving the knitting machine needle acts in a known manner on the coupling point of the knitting machine needle. The knitting machine needle according to the invention can also include a latch. The tongue can be pivoted on the shank in such a way that in its closed position it closes the interior of the hook and that the tip of the tongue in its retracted position in the longitudinal direction of the shank is on the first Drive section has. The tongue can be rotatably mounted on the shank on pins formed on the shank, a hinge or an axle.

The knitting machine needle according to the invention is characterized by a predetermined breaking section for separating the hook from the first driving section, which is formed by a section of the shank extending in the longitudinal direction thereof. A "section", as used herein, means greater than infinitesimal length in the longitudinal direction of the needle. The frangible portion is located entirely within a first shank portion extending in the longitudinal direction of the shank between the tip of the hook and the first drive portion.

Surprisingly, it has been shown that the problem of damage to needle beds and locks is counteracted to a considerable extent by such a predetermined breaking section, which develops its effect in relation to the shank of the knitting machine needle and breaks it between the hook and the first drive section.

A predetermined breaking portion has a non-infinite extent in the longitudinal direction of the knitting machine needle. The knitting machine needle is likely to break at the breaking point due to forces transmitted through the yarn when the movement of the needle in the needle bed is impeded or the stitch fails to be knocked over. In the sense of the present publication, the shank of the knitting machine needle extends over the entire length of the same. The shaft can only be divided into different functional sections. An end portion of the shank forms a hook and has adjacent to this hook a portion which can come into contact with a yarn in the knitting process. Furthermore, the shank includes a section (the drive section or butt) via which the movement of the knitting machine needle is initiated. Sections lying between the above sections are used, for example, to guide the knitting machine needle (in a needle bed) and connect the above functional sections. A frangible portion will advantageously be located in a portion of the shank that serves the functions of guiding and connecting other functional portions. The shank can have sections with different heights. The sections of the shaft of different heights can merge into one another at transition points. A first transition point may be located near the drive section. A second transition point may be located near the hook. The second transition point can be double or longitudinal in the longitudinal direction spaced three times as far from the tip of the hook as the tip of the tongue in the supine position of the tongue. The distance of the second transition point from the tip of the hook can also have any value between the above values.

The knitting machine needle can have a predetermined breaking section, which is set up in such a way that the hook can be separated from the first drive section by a force that acts on the hook and is less than 80% of the force at which a needle of the same construction without a predetermined breaking section is permanently deformed. The predetermined breaking section can in particular be set up in such a way that the hook can be separated from the first drive section when a corresponding force acts on the hook in a negative vertical direction. It is clear to the person skilled in the art that at least the diameter ("fineness") of the yarn is related to the breaking strength of the needle and that the breaking strength is certainly also determined by the fineness of the needle. The fineness also determines the maximum diameter of the yarn to be used. The tensile strength of the yarn is certainly also largely dependent on the yarn diameter, so that the overall fineness is a needle property that has a major influence on the design of the predetermined breaking section. The gauge (or "press") of the knitting machine needle may be determined by the gauge of the tape from which the knitting machine needle is stamped and may be measured in the width direction of the knitting machine needle. With a needle with a pressure of 0.4mm, the force at which the hook is separated from the first drive section can be approximately from 5N to IN depending on the design of the predetermined breaking section, while a knitting machine needle of the same construction would be permanently deformed at approximately 8N. "Deform" is used here in particular as a generic term for "bending". A special test for verifying the suitability of a predetermined breaking section consists of placing the needle with its underside (the side facing away from the foot in its height direction) on a table, pushing the needle on the table, hook first, over the edge of the table until the hook-side (front) part of the needle protrudes at least up to the predetermined breaking section over the edge of the table. If the hook is then subjected to a defined breaking or buckling force, the break should take place at the predetermined breaking section. If the force is further increased (examples see above) and plastic deformation occurs and there is no breakage, the suitability of the needle for the purposes of this document must be doubted.

The knitting machine needle may have a predetermined breaking portion located entirely within a second shank portion, the second shank portion being in Extends longitudinally of the shaft between the position of the tip of the tongue in the retracted position of the tongue and the first drive section.

The knitting machine needle may have a predetermined breaking portion which is located entirely in a third shank portion which begins in the longitudinal direction of the knitting machine needle at the point which is spaced two tongue lengths from the point of articulation of the tongue in the direction of the first butt and in the longitudinal direction of the knitting machine needle terminating at the point three tongue lengths from the pivot point of the tongue toward the first drive portion, the tongue length being the distance between the pivot point of the tongue and the tip of the tongue. This articulation or bearing point of the tongue can have a bearing seat in the tongue in the form of a circular opening into which an axle or a pin engages. The tongue length can be measured from the center of this opening. The tip of the tongue is the point of the tongue that is farthest from this center point, and the distance between these two aforementioned points can represent the length of the tongue. By specifically determining the position of the breaking portion in the longitudinal direction of the knitting machine needle, the dispersion among individual specimens of a plurality of knitting machine needles in the force value at which the hook is separated from the driving portion can be reduced. The predetermined breaking section can be located in a fourth or fifth shaft section. A fourth shank portion may extend from the pivot point of the tongue to a second transition point. A fifth shank portion may extend from the position of the tongue tip in the rear position to a second transition point. In the case of knitting machine needles without a latch (such as compound needles), the predetermined breaking section can be located in a sixth shank section described below: compound needles have guide means for a slider (a hook closing element) at a distance in the longitudinal direction from the point of the hook, which are located in the longitudinal direction on the drive section extend. These guide means do not extend below the tip of the hook. This results in a minimum distance between the tip of the hook and the guide means in the longitudinal direction. The sixth shank portion may extend from 1.5 times the minimum distance to three times the minimum distance from the hook tip.

The knitting machine needle can have a distance of at least 75 mm from the hook-side end of the needle in the longitudinal direction of the shank to the hook-side beginning of the first drive section or the first butt in the longitudinal direction.

The knitting machine needle can have a shank which has a height ("chest height") of 0.8 to 1.5 mm in the area in which the latch is articulated on the shank, at the highest point in this area. This height is measured in the height direction. The knitting machine needle can have a shank which, in the section in which the predetermined breaking section is arranged, can have a height which is between 50% and 70% of the breast height.

The knitting machine needle can have a shank which is stamped out of a band material and which, in the areas in which its thickness still corresponds to the thickness of the band material, has a thickness, measured in the width direction, of 0.3 to 0.6 mm or up to 0.7 mm to have.

The knitting machine needle can include a predetermined breaking section, which has a reduction in the shank cross section perpendicular to the longitudinal direction. In particular, the plane spanned by the height direction x and the width direction y of the needle runs “perpendicular to the longitudinal direction”.

The knitting machine needle can have a predetermined breaking section, which has a reduction in the shank cross section, which is achieved by reducing the shank in the vertical direction. A predetermined breaking section designed in this way can have the advantage that it can also be attached during a stamping process and thus no separate manufacturing process is required. The predetermined breaking section can thus be produced inexpensively. The height of the shaft can be reduced in the height direction from above and/or from below. However, it would also be conceivable to provide a recess (or several) in the shank that does not reach through the upper side and the underside of the shank or the predetermined breaking section. The knitting machine needle can have a predetermined breaking section which, at the point with a maximum reduced cross section, has a reduction of at least 10% and at most 60% in the height or the height dimensions of the adjoining shank or the adjoining shank sections. This leaves 40% to 90% of the cross-sectional area (in a plane transverse to the longitudinal direction of the needle) at the thinnest point of the predetermined breaking section. In particular, when there are a plurality of indentations that engage the shaft from different directions (e.g. from above and from below), the reduction in cross-section or height in question can also be distributed over different sub-sections of the predetermined breaking section (20% from above, 25% from below). A notched configuration of the cross-sectionally reduced points of the predetermined breaking section makes it possible to obtain a position that is relatively precisely defined in the longitudinal direction for separating the hook from the drive section. A concentration of stresses takes place at the position of the frangible portion. In addition or as an alternative, the width of the needle can of course also be reduced. The procedure can be equivalent to the measures described above for reducing the height of the shaft dimensions.

The knitting machine needle may have a shank reduction in the height direction, which has a triangular shape with an included angle of 60° to 120°. An opening angle of 90° can be particularly advantageous. The three corners formed in the shaft can be rounded. With small reductions in the height direction, a radius of rounding of at least 0.02 mm is advantageous, with larger reductions in the height direction, the roundings can also advantageously be designed with radii of 0.35 mm or, for example, 0.4 mm or 0.5 mm. The reduction in height can also be trapezoidal, in the form of a step or have a different geometry. In view of the above, the differences to grooves, which for example relieve the stitches when sliding over the tongue in their backward position, become clear: Such grooves have a larger opening angle and a flat profile to allow the stitch to enter and exit easily . In contrast, most predetermined breaking sections should bring about a defined break at a defined point, so that the opening angles of the side flanks are smaller in such a predetermined breaking section. Also because of the specific shape that is advantageous for a predetermined breaking section, it is advisable to position such a predetermined breaking section in a place that is out of the question for a stitch relief groove: the stitch relief groove is in a place over which the stitch slides. Due to its shape, the predetermined breaking section could "catch" the stitch and thus endanger the knitting process. Therefore, as mentioned, it is advantageous to position the predetermined breaking point, for example, behind the position of the tip of the latch when the latch is in the back position. Another consideration that speaks in favor of positioning the predetermined breaking section in the rear area of the needle is the leverage effect: when a stitch, and here in particular a stitch that has not been knocked off transfers large force to the interior of the hook, the distance from the hook increases the leverage of that force on the breakaway portion.

The knitting machine needle can have a predetermined breaking section, the material of which has a lower elongation at break than sections of the remaining shaft. The behavior of the knitting machine needle in the event of an overload can be specifically controlled by this embodiment of the predetermined breaking section (in addition to or as an alternative to a reduction in height or similar measures). Different deformations in the plastic range of the material are suppressed in favor of a targeted break when the load for which the knitting machine needle is designed is significantly exceeded. The knitting machine needle is advantageously made of steel. In the case of steel, the elongation at break can be influenced by specifically adjusting the hardness or the structure. In this way, the structure in the predetermined breaking section can be designed to be brittle and/or coarse-grained.

As already mentioned at the outset, problems with damage to needle beds and cams primarily occur in knitting systems in which long, slender knitting machine needles are used at high knitting speeds. The term "needle beds" is used in the present publication as a generic term for those parts of knitting systems that guide needles during knitting. In particular, these are knitting cylinders and dials on circular knitting machines and flat needle beds on flat knitting machines.

the DE3311361A1 and the DE102014118217A1 describe measures to be able to further increase the performance of high-speed knitting machines and show examples of typical knitting systems with corresponding knitting machine needles in the figures. The present invention deals in particular with the improvement of knitting machine needles and knitting systems which are suitable for the high-performance requirements indicated in these documents. The two publications describe knitting systems with knitting needles that have a very long, thin shank section between the hook and the first foot. Large parts of this long and thin shank section are guided laterally (in the direction of the width of the needle) in the relevant needle beds according to the two aforementioned documents, not by webs of the needle bed, but by sinkers. Knitting systems of the aforementioned type achieve high knitting performance with a high degree of fineness.

The knitting system according to the invention contains a needle bed with guide means and at least one channel base, which are set up to receive knitting machine needles and to guide and support them in their longitudinal direction during their intermittent movement. Here, needle beds in the form of cylinders, dials or flat needle beds, for example for flat knitting machines, can be considered. The knitting machine needles are accommodated in channels by the needle bed and are guided by the channel webs in the width direction of the knitting machine needles and are supported by the channel base in the negative height direction of the knitting machine needles. In particular, the guidance of the knitting machine needles in the width direction does not necessarily take place along the entire length of the knitting machine needle, but can also only take place in a rear section of the knitting machine needles. In other sections of its length, the knitting machine needle can also be guided in the width direction, for example, by other knitting tools (this is the case, for example, with knitting systems according to the publications DE3311361A1 and the DE102014118217A1 the case). The same applies to the support of the knitting machine needles on the bottom of the channel.

The knitting system according to the invention also contains at least one cam part for transmitting force to at least a first drive section of a knitting machine needle accommodated in the needle bed. A butt of the knitting machine needle often protrudes from the channel of the needle bed and is accommodated in a web-shaped indentation ("cam") in the cam. Normally, a circular knitting machine has a plurality of cams, each of which defines a portion of the path that a needle butt (of a clutch part) travels in one total rotation of the needle cylinder of a circular knitting machine. This relative movement of the knitting machine needle to the cams in the width direction of the needle, the cams transmit the force to the relevant drive section or needle butt that moves the needle in the longitudinal direction of the needle during knitting in a circular knitting machine.

• einen Haken zur Bildung von Maschen, der den Schaft in der Längsrichtung des Schaftes begrenzt und der in einer Hakenspitze ausläuft,
• einen in der Längsrichtung des Schaftes auf den Haken folgenden ersten Antriebsabschnitt
  •

The subject matter of the present publication is also a knitting system that has a number of knitting machine needles, each of these knitting machine needles in turn having the following features:

• a hook for forming loops, which delimits the shank in the longitudinal direction of the shank and which ends in a hook point,
• a first drive section following the hook in the longitudinal direction of the shank
  •

The knitting system according to the invention is characterized in that at least one of the knitting machine needles has a predetermined breaking section for separating the hook from the first drive section. The predetermined breaking section is formed by a first section of the shank, which extends in its longitudinal direction. The frangible portion is located entirely within the first shank portion, which extends in the longitudinal direction of the shank between the tip of the hook and the first drive portion.

Due to the predetermined breaking section, exceptionally large forces acting on the hook in the negative vertical direction of the knitting machine needle result in the hook separating from the first drive section. As a result, these forces are not transmitted to the portion of the shank that is in close proximity to the lock part. This measure eliminates or at least reduces damage to the needle bed and cam parts caused by collisions.

The knitting system according to the invention can be designed in such a way that the guide means and the at least one channel base of the needle bed, the at least one cam part and the position of the drive section and the predetermined breaking section on the at least one knitting machine needle are coordinated in such a way that the at least one knitting machine needle during knitting operation is at least temporarily is driven so far out of the guide means that the guide means no longer at least partially support the predetermined breaking section of the at least one knitting machine needle. The predetermined breaking section is located above the first cam segment, at least when the knitting machine needle is in the driven-out state. This special tuning allows the behavior of the system to be precisely controlled when unusually high forces act on the hook or on the section of the knitting machine needle that is no longer supported. If necessary, the high forces can then act via a relatively long lever from the hook to the predetermined breaking section. Since the predetermined breaking section lies approximately at a point at which the needle bed begins to support the driven-out knitting machine needle, there is a high probability of a very defined break occurring at or in the predetermined breaking section. It is therefore important here that the predetermined breaking section is not arranged too far forward in the direction of the hook, because otherwise an undefined breakage would occur on the hook due to the leverage effect Point can arise at which the knitting machine needle is again supported by the needle bed. If the predetermined breaking section is completely in the supported area, an undefined break can occur at the edge of the needle bed. High forces can occur, for example, due to the fabric being pulled off if stitches are not knocked off and accumulate in the hook. A pull-off force can then quickly act on the hook, which exceeds the usually occurring pull-off force, for example by a factor of 2 or more.

Fig. 1

Figur 1 zeigt eine Strickmaschinennadel in einer Gesamtansicht

Fig. 2

Figur 2 zeigt einen vergrößerten Ausschnitt der Strickmaschinennadel aus Figur 1.

Fig. 3

Figur 3 zeigt einen vergrößerten Ausschnitt einer alternativen Ausführungsform einer Strickmaschinennadel ähnlich wie in Figur 2.

Fig. 4

Figur 4 zeigt eine alternative Ausführungsform einer Strickmaschinennadel in einer Gesamtansicht

Fig. 5

Figur 5 zeigt einen vergrößerten Ausschnitt der Strickmaschinennadel aus Figur 4

Fig. 6

Figur 6 zeigt einen vergrößerten Ausschnitt einer alternativen Ausführungsform einer Strickmaschinennadel ähnlich wie in Figur 5.

Fig. 7

Figur 7 zeigt den vergrößerten Ausschnitt der Strickmaschinennadel aus Figur 2 mit zusätzlicher Darstellung der Schließlage der Zunge und zwei Querschnittsansichten.

Fig. 8

Figur 8 zeigt ein Stricksystem gemäß der Erfindung in symbolischer Darstellung.

The use of needles according to the present document is in knitting systems, as in the DE3311361A1 and the DE102014118217A1 are described, particularly advantageous. The knitting systems, which are the subject of the present publication, advantageously have the additional properties of DE3311361A1 and the DE102014118217A1 on.

1

figure 1 shows a knitting machine needle in an overall view

2

figure 2 shows an enlarged section of the knitting machine needle figure 1 .

3

figure 3 shows an enlarged section of an alternative embodiment of a knitting machine needle similar to that in FIG figure 2 .

4

figure 4 shows an alternative embodiment of a knitting machine needle in an overall view

figure 5

figure 5 shows an enlarged section of the knitting machine needle figure 4

6

figure 6 shows an enlarged section of an alternative embodiment of a knitting machine needle similar to that in FIG figure 5 .

7

figure 7 shows the enlarged section of the knitting machine needle figure 2 with additional representation of the closed position of the cam and two cross-sectional views.

8

figure 8 shows a knitting system according to the invention in a symbolic representation.

figure 1 shows a knitting machine needle 1 in an overall view. The illustration is not to scale and details that are not essential to the invention have been omitted. The other figures are simplified accordingly. A coordinate system showing the directions defined on the knitting machine needle 1 is shown for clarification. The longitudinal direction of the knitting machine needle 1 is denoted by z, the width direction by y and the height direction by x. On in the figure 1 left end in the longitudinal direction z the knitting machine needle 1 is the hook 2. Not far from the figure 1 On the right end of the knitting machine needle 1 in the longitudinal direction z, the knitting machine needle 1 has a butt 5 (also referred to as the drive section 33). The foot 5 protrudes beyond the knitting machine needle 1 in the positive vertical direction x. Only one foot 5 on the knitting machine needle 1 is shown in all figures. However, it is conceivable in all of the exemplary embodiments for the knitting machine needle 1 to extend even further to the right and to have one or more additional butts. The shank 3 of the knitting machine needle 1 extends between the hook 2 and the foot 5. The shank 3 clearly has a long and slender shape. The length from the beginning 20 of the knitting machine needle 1 on the hook side to the beginning 19 of the first butt 5 on the hook side is approximately 78 mm in the present exemplary embodiment. For clarification, three sections (10, 11, 13) of the longitudinal extension of the shank 3 of the knitting machine needle 1 are shown with curved brackets. The first 10 and the second section 11 extend at their right end to the beginning of the first foot 5 on the hook side. On the shaft 3 in the third section 13, which is also encompassed by the first section 10 and the second section 11, there is a predetermined breaking section 9 appropriate. This and other details are shown in the enlarged view of the left area of the knitting machine needle 1 in FIG figure 2 better to recognize.

In the enlarged view of the figure 2 the hook tip (4) and the hook-side end 20 of the knitting machine needle 1 can be seen in particular. Yarn loops for stitch formation are held in the interior of the hook 2 below the hook tip 4 during the knitting process. The tongue 6, which is shown in its reverse position 8, is also involved in the stitch formation. In this position, the tip of the tongue 12 reaches a point at which it is maximally directed towards the foot 5 (also referred to as the drive section 33) in the longitudinal direction z. The tongue 6 is rotatably attached to the shaft 3 at the pivot point 14 . The shank 3 has a predetermined breaking section 9 which has a notch or cut-out in which the height of the shank or the shank dimensions in the height direction x is reduced from above. The recess in question has a triangular shape with a rounded tip. At the rounded tip, the triangle has an angle ("aperture angle") of 90°. The height of the shank 3 is reduced by approximately 50% at the point of the smallest remaining cross section.

the figure 3 essentially corresponds to the figure 2 , only an alternative exemplary embodiment of a predetermined breaking section 9 is shown. The amount of reduction in cross section is smaller than that in the embodiment of FIG figure 2 . There is no rounding of the tip of the resulting recess of the predetermined breaking section or it is so small that it cannot be seen in this representation. In each embodiment, the tip of the resulting recess can be rounded. The corners that occur on the upper edge of the shaft 3 on the left and right of the predetermined breaking section 9 can also have a rounding in all of the exemplary embodiments.

the figure 4 shows a further embodiment of a knitting machine needle 1 in an overall view. The knitting machine needle 1 largely corresponds to the knitting machine needle 1 figure 1 , only an alternative embodiment of a predetermined breaking section 9 is shown. In addition, a first transition point 28 and a second transition point as well as the fourth section 30 of the shank 3 and the fifth section 31 of the shank 3 are indicated with curly brackets. Starting from the foot 5, the shaft 3 has a maximum height up to the first transition point 28 (distance in the height direction x). After the first transition point 28 in the direction of the hook 2, the height of the shank 3 quickly reduces to a medium height. After the second transition point 29 in the direction of the hook 2, the height of the shank 3 is reduced again. The fourth section 30 of the shank 3 extends in the longitudinal direction z of the knitting machine needle 1 from the articulation point 14 of the latch 6 to the second transition point 29. The fifth section 31 of the shank 3 extends in the longitudinal direction z of the knitting machine needle 1 from the tip 12 of the Tongue 6 in the back position 8 up to the second transition point 29. A minimum height of the shaft 3 and thus a suitable position for a predetermined breaking section 9 can be determined in both areas. The shank section between the second transition point 29 and the first drive section 33 has a greater height of the shank and therefore does not offer an optimal position for a predetermined breaking section 9.

The predetermined breaking section 9 is shown in the enlarged view in FIG figure 5 better to recognize. The knitting machine needle 1 of figure 5 differs essentially only by the design of the predetermined breaking section 9 of the knitting machine needle 1 from the Figures 2 and 3 . The predetermined breaking section 9 is formed by reducing the height of the shank 3 in the height direction x from below. Otherwise this reduction "from below" is identical to that in figure 2 represented reduction "from above". As a general rule For all embodiments of the knitting machine needle 1, reductions in the shank cross section can advantageously be carried out from above, from below or from both sides. Alternatively or in combination, reductions in the width direction y can also be used. Additionally are also in the figure 5 the side flanks 25, the shape 26 of the height reduction, the dimensions of the shaft height in the zx plane and the opening angle 27 of the height reduction.

figure 6 shows an enlarged representation of the front area of a knitting machine needle 1, which, apart from the embodiment of the predetermined breaking section 9, essentially corresponds to that in FIGS Figures 1 to 5 illustrated knitting machine needles 1 corresponds. In this exemplary embodiment, the predetermined breaking section 9 is formed by a section of the shank 3 whose cross section is not adapted to form a predetermined breaking section 9 . Rather, the hatching of the shank 3 in the predetermined breaking section 9 symbolizes that the material of the predetermined breaking section 9 has adapted properties and in particular a lower elongation at break than neighboring regions 23 , 24 of the shank 3 . Such an adaptation of the material properties in the predetermined breaking section 9 can be advantageously used for all exemplary embodiments of the invention as an alternative or in combination with other measures such as cross-sectional reductions.

figure 7 essentially corresponds to the figure 2 . On the knitting machine needle 1 of figure 7 the tongue 6 is shown in its two extreme positions for clarity. The tongue is shown both in its closed position 7 and in its retracted position 8 . In addition, the adjacent areas of the predetermined breaking section 23, 24 are illustrated.

Furthermore, in figure 7 Cross-section lines AA and BB are drawn at two positions on shaft 3. The associated cuts are in figure 7 to the right of the knitting machine needle 1 and show the unreduced shank cross section 22 and the reduction of the shank cross section 21. In the background, the sections show the first butt 5 and the first transition point 28 as well as the second transition point 29.

figure 8 shows a section through a channel of the needle bed 16 of a knitting system 15 according to the invention. The cutting line is in the width direction y immediately in front of the side wall of the needle 1 (and parallel to the same). The knitting system 15 is similar to those in the references DE3311361A1 and DE102014118217A1 knitting systems shown, the representation is not to scale and essential for the knitting process Components - such as other knitting tools (mainly sinkers) - have been left out. As already mentioned above, the sinkers (not shown) guide the knitting needle 1 in its width direction y in the areas that come in front of the channel walls 17 in the longitudinal direction z of the needles 1 . The plate adjacent to the needle 1 would normally be partially visible behind the needle 1. The knitting machine needle 1 is guided in two dimensions by guide means 17 of the needle bed 16 . The knitting machine needle 1 is supported by the channel base 32 of the needle bed 16 in the vertical direction x. The knitting machine needle 1 is guided by two channel walls 17 in the width direction y. In the representation of figure 8 only one channel wall 17 of the needle bed 16 is shown, which guides the knitting machine needle 1 in the width direction y in its rear area, in which the butt 5 is also located (the sinkers, which do this in the front area, have been omitted, as mentioned). The butt 5 of the knitting machine needle 1 engages in the cam part 18 shown in section. In the front area of the needle 1, in particular from the hook 2 to the predetermined breaking section 9, the knitting machine needle 1 is not supported by the needle bed 16 in the vertical direction x in its illustrated position in the needle bed 16. The situation shown arises with knitting systems 15 according to the invention at least when the knitting machine needle 1 is driven out to the maximum during knitting operation. A predetermined breakage is particularly likely in an exit position of the needle 1 in which the needle bed 16 or other knitting machine parts no longer provide a support function for the predetermined breaking section 9 or at least large parts of the hook-side part of the needle in front of it. This applies all the more since in the load position shown by a force F, a predetermined breakage due to the front part of the needle 1 with the hook 2 “buckling away” is very likely. This buckling is favored by the length of the lever (here the distance between the hook 2 and the predetermined breaking section 9) (leverage). Reference List 1 knitting machine needle 2 hook 3 shaft 4 hook tip 5 Foot 6 Tongue 7 closed position 8th Tongue back position 6 9 Breakaway section of tongue 6 10 first section of shaft 3 11 second section of shaft 3 12 tongue tip 13 third section of the shaft 3 14 Point of attachment of tongue 6 15 knitting system 16 needle bed 17 means of guidance 18 lock part 19 beginning of the first foot on the hook side 5 20 Beginning of the knitting machine needle 1 on the hook side 21 Reduction of the shaft cross-section 22 shank cross-section 23 Neighboring area of the predetermined breaking section 9 24 Neighboring area of the predetermined breaking section 9 25 side flanks 26 Shape of the height reduction of the dimensions of the shaft height in the zx plane 27 Opening angle of height reduction 28 first transition point 29 second transition point 30 fourth section of shaft 3 31 fifth section of shaft 3 32 Channel base 32 of the needle bed 16 33 Drive sab cut f power x height direction y latitude direction e.g longitudinal direction

Claims (14)

1. Knitting machine needle (1) which comprises at least the following features:

   • a hook (2) which, for forming loops, delimits the shank (3) in the longitudinal direction (z) of the shank (3) and which tapers off in a hook tip (4) ;

   • a first drive portion (33) which in the longitudinal direction (z) of the shank (3) follows the hook (2);
   characterized by

   • a predetermined breaking portion (9) which, for separating the hook (2) from the first drive portion (33), is formed by a portion of the shank (3) that extends in the longitudinal direction (z) and that is situated entirely in a first shank portion (10), the latter in the longitudinal direction (z) of the shank (3) extending between the tip (4) of the hook (2) and the first drive portion (33).
2. Knitting machine needle (1) according to Claim 1, characterized by
   a predetermined breaking portion (9)

   • that breaks upon application of a force which acts on the hook (2) and is less than 80% of the force

   • at which a knitting machine needle of identical construction without a predetermined breaking portion (9) would be permanently deformed.
3. Knitting machine needle (1) according to Claim 1 or 2,
   characterized by
   a latch (6) which is pivotably disposed at the shank (3) in such a manner that said latch (6) in the closing position (7) thereof closes the interior of the hook (2) and that the tip of the latch (6), in the rearward position (8) thereof, in the longitudinal direction (z) of the shank (3) points towards the drive portion (33).
4. Knitting machine needle (1) according to Claim 3, characterized in that

   • the predetermined breaking portion (9) is situated entirely in a second shank portion (11),

   • wherein the second shank portion (11) in the longitudinal direction of the shank (z) extends between the position of the latch tip (12) in the rearward position of the latch (6) and the hook-proximal beginning (19) of the first drive portion (33).
5. Knitting machine needle (1) according to Claim 3, characterized in that
   the predetermined breaking portion (9) is situated entirely in a third shank portion (13)

   • which in the longitudinal direction (z) of the knitting machine needle (1) begins at that location that in the direction towards the first drive portion (33) is spaced apart from the pivot point (14) of the latch (6) by two latch lengths,

   • and which in the longitudinal direction (z) of the knitting machine needle (1) ends at that location that in the direction towards the first drive portion (33) is spaced apart from the pivot point (14) of the latch (6) by three latch lengths;

   • wherein the latch length is the distance between the pivot point (14) of the latch and the latch tip (12).
6. Knitting machine needle (1) according to one of the preceding claims,
   characterized in that
   the hook-proximal beginning (19) of the first drive portion (33) in the longitudinal direction (z) has a distance of at least 75 mm from the hook-proximal beginning (20) of the needle (1) in the longitudinal direction (z) of the shank (3).
7. Knitting machine needle (1) according to one of the preceding claims,
   characterized in that
   the drive portion (33) is formed by a butt (5) which in the positive height direction (x) of the shank (3) protrudes beyond the shank (3).
8. Knitting machine needle (1) according to one of the preceding claims,
   characterized in that
   the predetermined breaking portion (9), perpendicular to the longitudinal direction (z), comprises a reduction (21) of the shank cross section.
9. Knitting machine needle (1) according to the preceding claim,
   characterized in that
   the predetermined breaking portion (9) comprises a reduction (21) of the shank cross section (22) as a result of a reduction of the shank dimensions in the height direction (x).
10. Knitting machine needle (1) according to Claim 9, characterized by
    a predetermined breaking portion (9) which, at the location thereof having the greatest reduction (21) of the shank cross section (22), comprises a reduction of the shank dimensions in the height direction (x) of at least 10% and at most 50%.
11. Knitting machine needle (1) according to one of Claims 9 to 10,
    characterized in that
    the reduction of the shank dimensions in the height direction (x) has a profile which, in the plane defined by the height direction (x) and the longitudinal direction (z), has a triangular or trapezoidal shape (26), the lateral flanks (25) of the latter having a mutual opening angle of 60° to 120°.
12. Knitting machine needle (1) according to one of the preceding claims,
    characterized in that
    the predetermined breaking portion (9) at least in part comprises material with a lower elongation at break than portions (10, 11, 13) of the remaining part of the shank (3), and in particular than those regions (23, 24) of the shank (3) that are adjacent to the predetermined breaking portion (9).
13. Knitting system (15) which comprises at least the following features:

    • a needle bed (16) having guide means (17) and at least one channel base (32) which are provided for receiving knitting machine needles (1) and for supporting and guiding the latter in the intermittent movement thereof in the longitudinal direction (z) thereof;

    • at least one cam part (18) for applying force to at least one first drive portion (33) of a knitting machine needle (1) received in the needle bed (16);

    • a number of knitting machine needles (1), wherein at least one of the knitting machine needles (1) is embodied according to Claim 1.
14. Knitting system (15) according to Claim 13, characterized in that
    the guide means (17) and the at least one channel base (32) of the needle bed (16), the at least one cam part (18), as well as the position of the first drive portion (33) and of the predetermined breaking portion (9) on the at least one knitting machine needle (1) are provided for in such a manner

    • that the at least one knitting machine needle (1) in the knitting operation is at least temporarily driven out of the guide means (17) and the at least one channel base (32) so far

    • that the guide means (17) and the at least one channel base (32) at least temporarily no longer support the predetermined breaking portion (9) of the at least one knitting machine needle (1).

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