EP1921189B1 - Knitting machine needle - Google Patents

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.

Machine knitting needles are for example from the US 1629275 or even from the DE 29 07 569 B1 known.

From the U.S. Patent No. 3,164,000 there is known a machine knitting needle having a straight shank, a hook formed at the end of the shank, and a tongue slot in which a tongue is pivotally supported for opening and shooting the hook. The hook has a semicircular inside, followed by a straight, parallel to the needle back section. This goes over at a kink in a rising section, which leads to a plateau. The plateau is interspersed by the tongue slot.

From the DE 30 18 699 A1 is a similar hook needle with a pivotally mounted tongue known. The tongue slot of this hook needle extends here in the region of the rise. This does not change anything by the excessive acceleration of the tongue when sliding the stitch onto the shaft of the latch needle.

Furthermore, from the GB 2 169 320 A a tongue needle is known, which has, starting from the hook interior, a rise, which leads to a parallel to the tongue back plateau area of the tongue slot. The increase has a relatively low value in the hook and then increases steeper and steeper. With regard to the acceleration of the sliding over the shaft mesh and thus the acceleration of the tongue, this arrangement is unfavorable.

At such needles increasing demands are made in terms of higher knitting speeds. When knitting, the needle is moved back and forth in the longitudinal direction. Half stitches taken from 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. By way of illustration, such a needle P1 is in FIG FIG. 5 shown. Its tongue P2 experiences its acceleration through the half-stitch as the half-stitch slides over the rounded portion P3 of the maximum jaw height. Thus, the tongue is accelerated by the half-stitch in the relatively large angular range ε, resulting in a high impact velocity. With increasing knitting speed, the beating stops The tongue, especially in reserve, a problem in terms of durability of a machine knitting needle. It must be ensured that there is no inadmissible wear of the machine needle and in particular not to break the tongue or needle body over the period of use of the machine needle.

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.

But there are also aspects to consider that affect the thread. For example, it can come to the cutting of the thread on the tongue. The named DE 29 07 569 B1 provides to provide the tongue with a throat and to form the rise from the hook to the needle breast with a relatively large pitch angle β. Although this protects the thread, it leads to compromises in working speed. In particular, as explained above, a high tongue impact velocity of the tongue on the shaft results when the tongue beats in reserve.

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.

In the needle according to the invention, the geometry of the jaw rise reduces the load on the tongue and shaft when the tongue beats in reserve and strikes the shaft. By a second, straight portion of the jaw rise is achieved that the speed of a sliding from the hook interior over the jaw rise half-mesh is not too large. As a result, the speed transmitted from the half-stitch to the tongue is tolerable and less than in the prior art, in particular according to FIG. 5 ,

For example, in previous machine knitting needles, the rise of the jaw between the hook and the needle face is straight, with the pitch angle of the rise of the jaw rise decreasing only in the reverse region, ie, the highest point of jaw rise measured from the needle back. In the invention, the reversing portion is preceded by a straight rising portion whose pitch angle is constant at all points and smaller than the pitch angle of the upstream portion of the rise of the jaw rise. The second flatter straight portion of the jaw rise allows the reduction of the total height of the jaw to be measured from the needle back. This minimizes at least the distance that the stitch head must travel on the shaft of the needle in the same amount of time as the mesh legs and mesh feet of the half stitch. Thus, the acceleration of the mesh head and thus the acceleration of the tongue and thereby in turn their load is reduced when impacting in reserve.

With the design according to the invention too strong tongue acceleration is avoided by reducing the pivoting range of the tongue, in which a tongue acceleration takes place. The steeper first portion of the jaw rise causes an early increase in the semi-mesh seated in the hook interior as it slides in the direction of the tongue bearing. If the half stitch hits the tongue, an acceleration takes place (swing angle range σ). As the semi-stitch advances to the second shallower portion of the rise of the jaw, it has already overcome much of the climb and, thanks to the now smaller friction angle, is able to slide over the needle face at a relatively uniform speed. The tongue is not or at least almost not accelerated. This pivoting range is preferably greater than 90 °. As soon as the half-stitch leaves the second section, it accelerates again and the tongue. This is the small angular range ε. A large increase in speed is not recorded in this small angular range ε. It therefore encounters the stem at a reduced speed in tongue return with respect to the prior art. This effect allows a substantial increase in the operating speed of the machine knitting needle.

The jaw increase according to the invention can be realized by a two-stage ramp, which ensures that the half-stitch after being hit on the tongue, has to cope with a reduced pitch angle.

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

Figur 1

die erfindungsgemäße Maschinenstricknadel in einer schematischen ausschnittsweisen Prinzipdarstellung mit ihrer Zunge in verschiedenen Positionen,

Figur 2

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

Figur 3

die Nadel nach Figur 1 in einer ausschnittsweisen Seitenansicht in einer anderen Größe mit Halbmasche in Seitenansicht,

Figur 4

die Nadel nach Figur 1 mit Gestrick in einer Schnittansicht und

Figur 5

eine Nadel nach dem Stand der Technik in aus- schnittsweiser Seitenansicht.

Further details of advantageous embodiments of the invention are the subject of the drawing, the description or claims. The description is directed to some essential aspects of the invention as well as other facts. Further aspects can be found in the drawing. In the drawings, embodiments of the invention are illustrated. Show it:

FIG. 1

the machine knitting needle according to the invention in a schematic fragmentary schematic representation with her tongue in different positions,

FIG. 2

the needle behind FIG. 1 in a sectional side view in another size with tongue in closed position in side view,

FIG. 3

the needle behind FIG. 1 in a fragmentary side view in a different size with half stitch in side view,

FIG. 4

the needle behind FIG. 1 with knitted fabric in a sectional view and

FIG. 5

a needle according to the prior art in a cut-out side view.

In FIG. 1 and 2 a needle 1 is illustrated, which has an elongated shaft 2, on which end a hook 3 is formed. The shaft 2, for example, meandering into a needle body with a suitable means for driving the machine knitting needle 1, for example in the form of a foot, not shown. The hook 3 is associated with a tongue 4, which protrudes at a designated needle axis 5 upwardly convex position of the shaft 2 from a tongue slot 6 out in which it is pivotally supported by a tongue bearing 7. The tongue bearing 7 is in FIG. 1 as well as the other figures only schematically indicated. It allows the transfer of the tongue 4 in a closed position in which it rests against the hook 3 (in FIG. 2 shown in solid line) and in a reserve (in FIG. 2 shown in dashed lines), in which the tongue is pivoted as far as possible away from the hook 3.

The needle breast 5 is provided with a jaw rise 8, which extends as the needle back 9 opposite contour of the hook 3 on the tongue bearing 7 away. This jaw rise 8 is preferably subdivided into several sections. A hook-side portion that forms a region 10 is preferably approximately straight in side view and begins within the hook 3. It runs approximately parallel to the needle back 9 or at a pitch angle of a few degrees. At a point 11 begins a first portion 12, which is preferably formed straight in side view. The point 11 adjoins the hook interior, which is bounded by the tongue 4, the shaft 2 and the hook 3. The slope of the first section 12 is determined by a pitch angle γ. It is preferably in the range of 5 ° to 20 °. The pitch angle γ is the angle between the portion 12 and the needle back 9. At the point 11 is preferably a rounded transition between the area 10 and the first portion 12 is provided.

The first portion 12 extends to a point 13 which is adjacent to the tongue 4 when in the closed position. In needle side view, this means that the point 13 can be found between a tongue inner side 14 and a tongue back 15. At the point 13, the jaw rise 8 merges into a second straight section 16 which has a pitch angle β. This pitch angle γ is to be measured to the needle back 9. It is smaller, preferably significantly smaller than the pitch angle β of the first section 12. The straight section 16 preferably continues up to a point 17, which is still seen next to the tongue 4, but preferably already from the point of view of the hook 3, behind the back of the tongue 15 lies. At the point 17, a preferably rounded reversing section 18 begins, in which the jaw 5 reaches its greatest height BH. Beyond the turnaround section 18, the shaft 2 becomes slimmer again. The reversing portion 18 is preferably from the perspective of the hook 3 behind the tongue bearing. 7

By this configuration, the needle 1 and the jaw rise 8 will be described below with reference to FIGS FIGS. 3 and 4 explained behavior of the knitted fabric when transferring a half-stitch 19 out of the hook interior over the open tongue 4 away reaches the shaft 2. The hook interior is preferably concave, so that the reception of at least one thread is ensured safe. The largest possible hook interior allows the secure picking up of at least one thread. From this hook interior is a recorded thread forming a half-stitch 19, transferred over the open tongue 4 on the shaft 2 as described below.

According to FIG. 4 is the half-stitch 19 formed from a thread and consists of a head 20, two of these adjoining legs 21 and two mesh feet 22. With the mesh feet 22, the half-stitch 19 is anchored in the fabric already produced 23.

On the fabric 23 a withdrawal force F _{z is} exercised, which, as FIG. 3 illustrated on the left, is transferred to the half-stitch 19.

If the needle 1 is now expelled, a frictional force F _R between the mesh head 20 and the surface of the shaft 2 is generated. As a result, a relative movement is initially prevented and the half stitch 19 is carried along somewhat by the needle 1 in the direction of movement. It arises in the FIG. 3 at the second position from the left illustrated inclined position of the half-stitch 19 with an angle α _m . Only when the horizontal force component F _Fg (thread sliding force in the region 10) is greater than the friction force F _R , the mesh head 20 moves in the direction of the point eleventh

With continued movement of the needle 1, the half-stitch 19 then slides onto the first section 12. In order for the stitch head 20 to move, an additional force F _S must be applied here. This force F _S corresponds to the pitch angle γ = α _s , whereby the skew of the half-stitch 19 increases significantly. It has the angle α _ms , which represents the sum of the angle α _m and the angle α _s . If the half-stitch 19 then passes over the point 13, in the transition to the second section 16, takes the required to drive the half-stitch 19 Force because of the reduced pitch angle β of the second portion 16, compared to the pitch angle γ of the first portion 12, from. As a result, also reduces the skew, ie the angle α _ms , the half-stitch 19 and the head 20 of the half-stitch 19, or the half-stitch 19 as a whole can accelerate somewhat. This corresponds to the in FIG. 1 illustrated angle range σ for the tongue 4. The tongue 4 is thus accelerated in this angular range σ. The half-stitch then passes through the second portion 16 without substantial further acceleration. The tongue therefore pivots out of the FIG. 1 The area shown on the left is essentially unaccelerated in the in FIG. 1 right-side area. Only when the half-stitch 19 passes the reversing section 18, a further significant acceleration of the relative speed between the head 20 of the half-stitch 19, or the half stitch 19 as a whole, and the shaft 2 of the needle 1 occurs. This corresponds to the acceleration range ∈ of the tongue 4 in FIG FIG. 1 right.

The acceleration ranges δ and ε are substantially smaller in the needle 1 according to the invention than in the needle P1 according to the prior art FIG. 5 , Between them is a large pivoting range without significant acceleration of the tongue 4. As a result, the speed of the tongue 4 is reduced when hitting the shaft 2. This leads to a lower kinetic energy, with the tongue head in reserve. In this way, tongue and jaw breaks are largely avoided even at higher knitting speeds.

To reduce the impact velocity of a tongue 4 of a needle 1 in reserve by reducing the acceleration effect emanating from a half-stitch 19 is the rise of the jaw 8 of the needle 1 formed divided into different areas. A first section 12 rises with a comparatively large acute angle γ of, for example, up to 20 °, preferably 16 °. Shortly after the half-stitch 19 has contacted the inner side 14 of the tongue 4, it reaches a second portion 16 of the jaw rise 8. The second portion 16 is a straight portion which increases at a smaller acute angle β of, for example, only 14 ° or less. Thus, an accelerating action of the half-stitch 19 on the tongue 4 over a wide pivoting range thereof is avoided. Preferably, this acceleration-free pivoting range is at least 90 °, preferably greater than 110 °.

LIST OF REFERENCE NUMBERS

1

Machine knitting needle

2

shaft

3

hook

4

tongue

5

needle breast

6

latch slot

7

latch bearing

8th

Back rise

9

needle back

10

Area

11

Job

12

first section

13

Job

14

Tongue inside

15

dorsum

16

second part

17

Job

18

reversal section

19

half stitch

20

stitch head

21

mesh sides

22

mesh feet

23

knitted

Claims (9)

1. Machine knitting needle (1), in particular for circular knitting machines,
   with a needle blade (2), on the free end of which a hook (3) is configured and which has a needle back (9),
   with a latch (4), which is mounted in a slot (6) of the blade (2) by means of a latch mounting (7) to pivot between a closed position and a retracted position,
   wherein extending from the hook (3) to the latch mounting (7) the blade (2) has a cheek slope (8) with a first straight upward sloping section (12) and with a second straight upward sloping section (16),
   wherein the second section (16) has an angle of slope (β) to the needle back (9) that is smaller than a defined angle of slope (γ) from the first section (12) to the needle back (9).
2. Machine knitting needle according to claim 1, characterised in that a rounded transition point (13) is configured between the first section (12) and the second section (16).
3. Machine knitting needle according to claim 1, characterised in that a transition point (13), which is laterally adjacent to the latch (4) when this is situated in closed position, is configured between the first section (12) and the second section (16).
4. Machine knitting needle according to claim 1, characterised in that the second section (16) extends as far as a return area (18), in which the cheek slope (8) has its greatest height measured from the needle back (9).
5. Machine knitting needle according to claim 1, characterised in that the length of the second section (16) corresponds to a pivoting range of the latch (4) of more than 90°.
6. Machine knitting needle according to claim 1, characterised in that the first section (12) and the second section (16) enclose an obtuse angle (180° - β) to one another, which is larger than 165° and smaller than 180°.
7. Machine knitting needle according to claim 1, characterised in that the angle of slope (β) is larger than or equal to 5°.
8. Machine knitting needle according to claim 1, characterised in that the angle of slope (β) is smaller than or equal to 14°.
9. Machine knitting needle according to claim 1, characterised in that the latch (6) is concave on its side facing the blade (2).

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