EP1767678A1 - Knitting machine needle - Google Patents

Abstract

Knitting machine needle comprises a shaft with a terminal hook (3) that forms a 180[deg] bend and tapers to a tip (12), and a latchet (6) that pivots on a bearing (9) on the breast of the needle between a closed position and a rearward position. Between the hook and the latchet bearing, the shaft has an angle of inclination, defined as the angle between any point on the shaft contour (17) and a line parallel to the back (16) of the needle, that always decreases in the direction of the breast (7) of the needle.

Description

The invention relates to a machine knitting needle, which is particularly intended for high-speed circular knitting machines, but in principle also suitable for all other types of knitting machines or warp knitting machines.

In use are machine knitting needles, such as those from the US 1629275 are known, with increasingly higher knitting speed reciprocated in the longitudinal direction. Meshes caught by the hook of the needle slide on the shaft, for example moving a tongue provided on the machine knitting needle in reserve. This movement is supported by the self-inertia of the tongue. Therefore, the tongue oscillates between the closed position and the reserve, wherein it alternately strikes the hook and the shaft. With increasing knitting speed, the striking of the tongue, in particular in reserve, represents a problem with respect to the durability of a machine knitting needle. It must be ensured that over the period of use of the machine knitting needle no undue wear of the machine knitting needle and in particular does not break the tongue or needle body , To remedy this, it has already been attempted to dampen the impact of the tongue as it pivots in reserve and strikes the shaft. This reveals the DE 27 14 607 C3 a special embodiment of the needle slot, which is bounded by more or less elastic sheep cheeks. The elastic sheep cheeks catch the tongue elastically and dampen the impact.

The aim is to use the latch needles at ever higher operating speeds.

It is an object of the invention to improve the machine knitting needles in this sense.

This object is achieved with the machine knitting needle according to claim 1. The needle according to the invention has a shaft which has a convex shaft contour between the hook and the needle breast. With this measure, the load of the tongue and the shaft is reduced when the tongue beats in reserve and impinges on the shaft. In previous machine knitting needles, the shank contour between the hook and the needle face, which consists of the neck and the breast rise, is substantially concave. The neck forms the transition between the hook or the head and the breast rise. Breast elevation is the connection between the needle's breast, ie the arched elevation in which the tongue is attached, and the neck of the machine-knitting needle. The thread thus increases, if it is to slide from the hook interior over the neck and over the breast rise on the needle breast, the stem contour. The friction angle of the thread increases steadily as it moves in the direction of the needle's breast. In the transition from the shaft contour, ie from the breast rise to the needle breast, the friction angle is relatively large. Thus, there is a high thread tension. Due to the rapid reduction of the slope at the transition point, the friction angle decreases almost suddenly. The still prevailing high thread tension and the now missing friction angle let the thread jump over the needle chest in a short time, whereby the resulting from the thread tension pulse is passed to the tongue on. This therefore strikes the shaft at high speed in reserve. This proves to be the cause of tongue or needle breakage in many cases. With the design according to the invention, this is exactly what is avoided. The non-concave stem contour causes an early increase in the mesh in the hook interior when it slides in the direction of the tongue bearing. If it hits the tongue, it has already coped with a large part of the climb and can now glide over the needle face with a gradually decreasing friction angle at a relatively steady speed. Because of the elimination of the jump-like mesh movement, the tongue is accelerated less strongly and consequently encounters the tongue with reduced speed in tongue return. This effect allows a substantial increase in the operating speed of the machine knitting needle.

Preferably, the non-concave stem contour already begins within the hook, and again preferably immediately after the concave throat portion of the hook. The transition point is then preferably at a location that is at least as far away from the bearing as the taper portion of the hook tip.

Preferably, the radii of curvature of the hook inner contour and the shaft contour are each substantially constant. The center of curvature of the hook inner contour lies in the hook interior. The center of curvature for the non-concave, preferably convex, shank contour lies below the bottom of the needle or the back of the needle.

Basically, the non-concave stem contour forms a rounded ramp which ensures that the pitch angle that the mesh faces as it moves from the hook interior across the needle face, steadily decreases even before the stitch hits the tongue.

In this context, it is also advantageous if the tongue is concave on its side facing the hook interior. This reduces on the one hand the mass of the tongue and leaves the stitch relatively late, i. only hit the tongue at relatively low pitch angles.

Further details of advantageous embodiments of the invention are the subject of the drawing, the description or claims.

Figur 1

die erfindungsgemäße Maschinenstricknadel in einer perspektivischen Prinzipdarstellung,

Figur 2

die Nadel nach Figur 1 in einer ausschnittsweisen Seitenansicht in einem anderen Maßstab mit Zunge in Schließlage,

Figur 3

die Nadel nach Figur 2 mit Zunge während des Öffnungsvorgangs,

Figur 4

eine abgewandelte Ausführungsform der erfindungsgemäßen Maschinenstricknadel mit Zunge in Schließlage in ausschnittsweiser Seitenansicht,

Figur 5

die Maschinenstricknadel nach Figur 4 mit Zunge während des Öffnungsvorgangs und

Figur 6

eine schematische Veranschaulichung der Zungennadel nach Figur 4 in Seitenansicht.

In the drawings, embodiments of the invention are illustrated. Show it:

FIG. 1

the machine knitting needle according to the invention in a perspective schematic representation,

FIG. 2

the needle of Figure 1 in a fragmentary side view on a different scale with tongue in the closed position,

FIG. 3

the needle of Figure 2 with tongue during the opening process,

FIG. 4

a modified embodiment of the machine knitting needle according to the invention with tongue in the closed position in a sectional side view,

FIG. 5

the machine knitting needle of Figure 4 with tongue during the opening process and

FIG. 6

a schematic illustration of the latch needle of Figure 4 in side view.

FIG. 1 illustrates a machine knitting needle 1 which has an elongated shank 2, on the end of which a hook 3 is formed. The shaft, for example, meandering into a needle body 4 with a suitable means for driving the machine knitting needle 1, for example in the form of a foot 5, over.

The hook 3 is associated with a tongue 6 which protrudes at a designated as needle breast 7 upwardly convex position of the shaft 2 from a tongue slot 8 out in which it is pivotally supported by a tongue bearing 9. The tongue bearing 9 is indicated only schematically in Figure 1 as well as the other figures.

The hook 3, as shown in Figure 2, preferably has an approximately uniform e.g. round, oval or circular cross section, which merges at a point 10 in a tapered portion 11, which has approximately the outer shape of a truncated cone and is slightly rounded at its end forming a hook tip 12. The hook 3 essentially forms a 180 ° bend, which defines a concave inner contour. It follows a curvature with the radius R1, around a center of curvature 13, which lies in the hook interior 14. The radius R1 is preferably constant. However, it can also vary slightly along the hook inner contour 15. Also, different portions of the hook inner contour 15 may have different centers of curvature 13, 13 '.

Subsequent to the hook 3, the shaft 2 of the machine knitting needle merges into a substantially straight needle back 16, wherein the height H of the shaft 2 measured perpendicular to the needle back increases towards the tongue support 9. The Shaft 2 bounds the hook interior 14 between the hook 3 and the tongue bearing 9 with a shaft contour 17 consisting of a neck 32 and a breast rise 31. The neck 32 begins at the point 10 and ends at the solder L2 of the point 33 at which the breast rise 31 begins. The point 33 is found by the solder L2 is dropped on the needle back 16 of the end 34 of the spoon 22 (Fig. 2). The point 34 represents the transition between the end of the bucket 22 and the shank of the tongue 6. The slope of the shank contour 17, starting from the end 18 of the hook inner contour, does not increase; preferably the slope decreases. In the embodiment according to FIG. 2, the pitch is almost constant starting from the end 18, ie the transition region from the hook inner contour 15 to the shaft contour, into the partial region 19 of the breast 7. This portion 19 is covered in the closed position of the tongue 6. The breast rise 31 ends at the point 35 at which the portion 19 begins. The pitch is defined as the angle α between the respectively considered point of the shaft contour 17 and a parallel to the needle back 16 line 20, 21. In the embodiment according to Figure 2, the shaft contour 17 follows from the end 18 to 19 in the area with less Curvature above a straight line. The angle α decreases slightly from the end 18 of the stem 17 to the point 33. The area 18 is within the hook 3, ie at least within a range which is bounded on the one hand left in Figure 2 by the hook inner contour 15 and right by the tip 12 of the needle back 16 like lot L. The end 18 is preferably located in a region which is bounded on the left by the contour 15 and on the right by a solder L1 which is cut from the point 10 onto the needle back 16.

The end 18 of the shaft contour 17 is closer to the needle back 16 than the tongue bearing 9 in the embodiment of FIG Needle back 16 and to be found at the point 35 end of the shaft rise 17 is greater than the distance between the center of the tongue bearing 9 and the needle back sixteenth

In another embodiment (not shown), it is possible that the distance of the end 18 of the stem contour 17 to the needle back 16 is smaller than the distance between the needle back 16 and the highest point of the needle breast 7. This means that the location 18 in FIG vertical direction, perpendicular to the needle longitudinal direction, between or on the center of the tongue bearing and the highest point of the needle breast 7 is located.

The machine knitting needle 1 described so far operates as follows:

During operation, the machine knitting needle 1 is rapidly moved back and forth in the shaft longitudinal direction. During the needle retraction (movement in Figure 2 to the right) moves the tongue 6, driven by the thread 28 which moves on the shaft back on the tongue shaft in the direction of hook 3, on the hook 3 and closes the hook interior 14 with her spoon 22. The tongue 6 is then in the closed position.

When expelling the needle, ie, in a rapid movement in Figure 2 to the left, runs in the hook interior lying thread 23, starting from the position illustrated in Figure 2, approximately in the vicinity of the end 18 on the shaft contour 17 in the direction of the tongue 6. The tongue 6 moves under the action of their own inertia and / or the tension of the inside 24 adjacent thread 23 towards their reserve to. It pivots about a defined by the tongue bearing 9 axis of rotation. The pivoting movement is indicated in Figure 3 by an arrow 25. Due to the uniform rise of the shaft contour 17, starting from the hook 3 to the needle breast 7, a persistence or a delay of the thread in the region of the hook-side end of the needle breast 7 is avoided. The thread 23 thus receives a relatively constant sliding speed. Speed peaks are deliberately avoided. The motion pulse and thus the possibility of transmitting the motion impulse from the thread 23 to the tongue 6 is thus minimized. The pivoting speed of the tongue 6 thus remains relatively low. If the tongue hits the shaft in reserve, the impact velocity is there in a relatively moderate range. Wear effects and the rebound of the tongue is thereby reduced. In addition, there is an improvement in the stitch pattern, ie the quality of the product produced, by the evening out of the thread sliding speed. In addition, thread damage and concomitantly dust formation during knitting can be reduced.

The machine knitting needle 1 is usually reciprocated by means of a knitting lock in the longitudinal direction. The transfer of forces takes place via the foot 5 of the needle 1, which follows the substantially sinusoidal knitting curve of the knitting lock. The machine knitting needle 1 reaches its highest speed between the two reversal points, while in the area of the reversal points itself a rather low needle speed is present. Taking into account the dynamic conditions, the non-concave shaft contour and in particular the convex shaft contour prove to be particularly advantageous: When the machine knitting needle 1 is ejected, the thread 23 overcomes the initially high gradient of the shaft contour 17 at a comparatively low needle speed. As the machine knitting needle 1 approaches its maximum speed, the stitch is in a region of the low slope breast rise 31. Overall, the movement of the stitch loop is thus considerably equalized. Taking into account this knowledge, the end 18 of the shaft contour 17 can be displaced in the direction of the tongue bearing 9 and thus also lie outside the hook interior 14. For example, the end 18 may be between the solder L and the location 33.

FIGS. 3 and 4 illustrate a modified embodiment of the machine knitting needle 1 which has been modified in terms of the aforementioned features, as illustrated in principle in FIG. The above description of the machine knitting needle 1 applies accordingly. In contrast to the above description, the convex shaft contour 17 is more curved. It follows, for example, a radius R2 whose center of curvature in FIGS. 4 and 5 lies below the needle back 16, ie outside the hook interior 14. The radius R 2 can be constant or vary from the end 18 to the needle breast 7, ie at least into the region 19. Likewise, different sections of the shaft contour 17 can be curved to different centers of curvature 26, 27. Independently of this, as FIG. 4 illustrates, the effect is achieved that the pitch angle α of the inner contour 17 in each case measured against a parallel to the needle back 16 line 20, 21 decreases from the hook 3 to the needle breast 7 out. In FIG. 4, the pitch angle α on the left is greater than on the right. This is achieved by the center of curvature 26, 27 around which the shaft contour 17 curves with the radius R2, as shown in FIG. 6, with respect to the direction of movement of the machine knitting needle 1 behind the solder L. The direction of movement B of the latch needle 1 is indicated in Figure 6 by an arrow. The perpendicular L meets the direction of movement B at right angles and passes through the tip 12 of the hook 3. While the hook 3 lies on one side of this solder L3, the center of curvature 26, 27 is on the other side of the solder. In all the embodiments described above, the needle back 16 is parallel to the direction of movement B. It may be inclined to the direction of movement B at an acute angle. In this case, the solders L and L1 are related to the direction of movement B. Otherwise, the previous description applies accordingly.

Due to the inclination of the shaft contour 17 decreasing towards the tongue 6, the friction of the thread 23, as it slides along the inner contour 17, continues to decrease towards the needle breast 7. As a result, the relative sliding speed between the machine knitting needle 1 and the thread 23 is made uniform, which greatly reduces the maximum thread sliding speed. This is effected in particular by the continuous decrease of the pitch angle α from the end 18 to the tongue 6 and the tongue bearing 9. The transmitted to the tongue 6 pulse of the thread 23 is minimized and connected, the maximum tongue speed is reduced. In particular, the impact speed of the Tongue 6 on the shaft 2 of the machine knitting needle 1 in the tongue reserve. Thus, the otherwise found cause of needle destruction or needle wear is greatly reduced. By using the needle according to the invention, the knitting speed can be increased and the service life increased.

Starting from its hook 3 between the hook 3 and its tongue bearing 9, the machine knitting needle 1 according to the invention has a convex shank contour delimiting the hook interior, which adjoins the concave hook inner contour at one end 18. It is thereby achieved that the pitch angle which a thread 23 lying in the hook 3 must overcome if it is to slide on the needle face 7 does not increase along the inner contour 17 at any point. Preferably, it even decreases steadily. He has its maximum value thus within a space bounded on the one hand by the hook inner contour 15 and on the other hand by a Lot L or L1, of the hook tip 12 or its taper portion 11 on the needle back 16 or if this is not parallel to the direction of movement B of Machine knitting needle 1 is oriented on the direction of movement B characterizing arrow is like. The convex shaft contour 17 merges steplessly into the likewise convex contour of the needle breast 7.

LIST OF REFERENCE NUMBERS

1

Machine knitting needle

2

shaft

3

hook

4

needle body

5

foot

6

tongue

7

needle breast

8th

latch slot

9

latch bearing

10

location

11

Rejuvenation center

12

top

13, 13 '

Center of curvature

14

Hook interior

15

Hook inner contour

16

needle back

17

stem contour

18

The End

19

Area

20, 21

line

22

spoon

23, 28

thread

24

inside

25

arrow

26, 27

Center of curvature

31

chest rise

32

neck

33

location

34

The End

35

location

B

movement direction

R1

radius

L, L1, L2

solder

H

leg height

α

lead angle

Claims (9)

Machine knitting needle (1), in particular for circular knitting machines,
with a needle shaft (2), at whose free end a hook (3) with a concave hook inner contour (15) is formed, which terminates in a tip (12),
with a tongue (6) which is pivotally mounted on a needle chest area (7) of the shaft (2) by a tongue bearing (9) between a closed position and a reserve,
wherein the shaft (2) starting from the hook (3) up to the tongue bearing (9) has a shank contour (17) whose inclination angle α decreases in the direction of the needle face. Machine knitting needle according to claim 1, characterized in that adjoining the tip (12) is a substantially frusto-conical narrowing section (11) and that the point (12) is rounded. Machine knitting needle according to claim 1, characterized in that one end (18) of the shaft contour (17) is arranged inside the hook (3). Machine knitting needle according to Claim 1, characterized in that one end (18) of the shaft contour (17) is arranged outside the hook (3). Machine knitting needle according to claim 1, characterized in that the distance from the needle back (16) to the end (18) of the shaft contour (17) is smaller than the distance from the needle back (16) to the highest point of the needle breast (7). Machine knitting needle according to claim 2, characterized in that the transition point (18) of the concave hook inner contour (15) to the shaft contour (17) of the shaft (2) at a location (18), of the tongue bearing (9) at least as far away is like the rejuvenation section (11). Machine knitting needle according to claim 1, characterized in that the radius of curvature (R2) of the shaft contour (17) is substantially constant. Machine knitting needle according to claim 1, characterized in that the shaft contour (17) is convex. Machine knitting needle according to claim 1, characterized in that the tongue (6) is concave on its side facing the shaft (2).

Images