EP2065498B1 - Latch needle - Google Patents

Description

The invention relates to a latch needle for knitting machines with a needle shaft, a hook formed thereon and a pivotally mounted in the needle shaft tongue.

To facilitate the knocking off of a loop from a latch needle, various modifications have already been proposed to the needle, which aim to make the stitch to be knocked off the needle as easy as possible to rise from the needle shaft through the closed tongue to the needle hook enable.

The DE 15 85 099 shows a latch needle, wherein the needle shaft tapers toward the needle hook, this taper is achieved in that the underside of the needle shaft has a rising toward the needle hook course. This reduces the cross section of the needle shaft towards the needle hook. A via the closed tongue to the needle hook sliding mesh learns by this cross-sectional reduction a smaller expansion, which facilitates the knocking off. However, the taper of the needle shaft of this known needle causes the opening width of the needle hook is reduced, which is particularly disadvantageous when multiple threads or one in relation to the hook size relatively thick thread to be inserted in the needle hook.

In addition, the taper of the needle shaft of this known needle only begins significantly after the articulation point of the tongue, which is why the mesh at the beginning of her movement on the closed needle tongue abruptly undergoes a relatively large expansion.

The US 1,629,454 1 shows a needle with a needle hub bent upwards relative to the optical needle shaft according to the preamble of claim 1.

The present invention has for its object to provide a latch needle, which facilitates the knocking off a mesh and thereby avoids the disadvantages described above.

The object is achieved with a latch needle for knitting machines with the features of claim 1. Due to the indentation of the needle shaft underside, this initially has an upward course and finally a downward course. This makes it possible to achieve a reduction in the diameter of the needle in the region of the closed needle tongue and yet to maintain a sufficient opening width of the needle hook. The reduction of the diameter of the needle in the region of the closed needle tongue avoids excessive widening of the stitch as it slides on the closed tongue and the needle hook. As a result, however, the opening width of the needle hook undergoes no constriction, even several threads or thick threads can be easily inserted into it.

So that already at the beginning of the sliding of the stitch on the closed tongue, the indentation can take effect, it is advantageous if the indentation begins at least approximately at the position of the needle shank, from which the closed tongue begins to protrude over the top of the needle shank. The tongue, by overhanging the top of the needle shaft, increases the diameter of the needle and thereby expands the loop. This is counteracted by the fact that the indentation reduces the needle diameter. The reduction of the needle diameter through the indentation should be made wherever the tongue protrudes above the needle shank. Therefore, it is further advantageous if the indentation ends at least approximately at the point of the needle shaft, which is opposite to the tip of the closed tongue. The indentation then extends over the entire area of the needle which is critical for the stitching during knock-off.

The indentation has a rising slope, a straight section and a sloping slope. This contour of the indentation can be produced easily in terms of production, with the transitions between the straight section and the bevels preferably being rounded.

The angle of the rising slope to the horizontal may be at least approximately equal to the angle between the top of the closed tongue and the horizontal. This means that the enlargement of the needle diameter by the tongue in the region of the bevels complete is compensated by the indentation, so the mesh undergoes no widening.

The straight portion of the indentation may preferably extend at least approximately parallel to the underside of the needle shaft in front of the indentation. In the area of the straight line, the needle undergoes no further reduction of the cross section through the indentation. This ensures that the needle still has sufficient stability even in the area of the indentation.

The sloping slope of the indentation can advantageously be at least approximately tangential to the outer contour of the needle hook, d. H. the indentation ends with their bevels on the needle hook. It is further advantageous if the sloping slope of the indentation extends at least approximately parallel to the inner contour of the needle hook. If the slope runs tangentially to the outer contour and parallel to the inner contour of the hook ensures that the needle hook is not weakened by the indentation. The material thickness and thus the stability of the needle hook are then not affected by the indentation.

Hereinafter, a preferred embodiment of a latch needle according to the invention will be described in more detail with reference to the drawing.

Show it:

Fig. 1

a partial side view of a latch needle according to the invention with the tongue open and lying on the needle shaft mesh;

Fig. 2

one of the Fig. 1 corresponding view of the needle with a closed tongue and at the transition region between the needle shaft and tongue lying mesh;

Fig. 3

one of the Fig. 1 corresponding view of the needle with mesh slipped on the tongue;

Fig. 4

one of the Fig. 1 corresponding view of the needle with tongue lying on the tongue spoon;

Fig. 5

one of the Fig. 1 corresponding view of the needle with tongue lying on the tip of the tongue.

The in the Fig. 1 to 5 shown latch needle 1 has a needle hook 2, which includes a hook space 20. The needle hook 2 is formed on a needle neck 3, which merges via a needle breast 4 in the needle shaft 6. On the needle shaft 6, a needle tongue 5 is pivotally mounted in a tongue slot 60 at a pivot point 50. The tongue 5 can by a mesh 100 of a in Fig. 1 shown opened position in a closed position, in the Fig. 2 to 5 is shown brought. By a tongue spring, not shown here further positions of the tongue 5 can be realized as a half-open or half-closed position.

At the bottom of the needle shaft 6 in the region of the needle neck 3, a mesh tension-reducing indentation 30 is provided. The indentation 30 begins in the region of the articulation point 50 for the tongue 5 and extends to the bottom of the needle hook second

The indentation 30 has, in the region of the articulation point 50, a first rising bevel 31, which preferably rises from the underside of the needle shank 6 at an angle which corresponds to the angle of the closed tongue 5. The slope 31 merges into a straight section 32, which preferably runs parallel to the underside of the needle shaft 6. The section 32 is spaced so far from the needle bottom, that although a reduction of the mesh tension is achieved, but nevertheless a sufficient strength of the needle neck 3 is ensured. Finally, the indentation 30 has a sloping bevel 33 which, in the example shown here, bears tangentially against the outer contour of the needle hook 2 and runs essentially parallel to the inner contour of the needle hook 2.

The transitions between the straight portion 32 and the two slopes 31, 33 are rounded as well as the transition from the needle shaft 6 into the first slope 31.

The design of the indentation 30 shown here by way of example prevents a sudden expansion of a loop 100, without thereby reducing the opening width of the needle hook 2.

The Fig. 1 to 5 show the mesh 100 in different positions on the needle 1 during the knocking.

In Fig. 1 By expelling the needle 1 by means of here not shown lock parts in the direction V of the double arrow P, the mesh 100 has the hook space 20 of the needle hook 2 on the needle neck 3 and the needle breast 4 is moved to the needle tongue 5 and thereby pivoted to its open position. Then she is over slid the bottom 51 of the open tongue 5 away on the needle shaft 6. By a subsequent return movement of the needle 1 in the direction R of the double arrow P, the mesh 100 comes into contact with the top 52 of the tongue 5, as in Fig. 1 shown.

When the needle 1 is further retracted, the loop 100 pivots the tongue 5 into its closed position and begins to slide on the top 52 of the tongue 5, such as Fig. 2 shows. The slope 31 of the indentation 30, which runs approximately parallel to the upper side 52 of the tongue 5, ensures that the needle diameter does not increase in front of the articulation point 50 of the tongue 5 in comparison to the diameter of the needle 1 behind the articulation point 50, ie the mesh 100 no widening experiences.

In Fig. 3 is the mesh 100 by further retraction of the needle 1 in the direction R of the double arrow P further moved on the tongue 5 to the front and is now at the transition of the slope 31 to the straight portion 32 of the recess 30th

Fig. 4 shows the mesh 100 at the end of the straight portion 32 of the recess 30 and at the beginning of the sloping slope 33rd

By further retraction of the needle 1, the mesh 100 enters the in Fig. 5 shown position immediately before knocking off. By the movement of the mesh 100 on the tongue 5 and at the same time on the sloping slope 33 of the indentation 30, the mesh has experienced a widening, which, however, takes place gently and is gentle on the thread.

The embodiment of the needle 1 shown here is merely exemplary.

Claims (7)

1. Latch needle for knitting machines with a needle stem (6), a needle hook (2) formed on it and a latch (5) mounted to pivot in the needle stem (6), whereby the underside of the needle stem (6) includes a recess (30) in the area between the attachment position (50) of the latch (5) and the needle hook (2), characterised in that the recess (30) includes a rising chamfer (31), a straight section (32) and a falling chamfer (33).
2. Latch needle according to claim 1, characterised in that the recess (30) begins at least approximately at the position of the needle stem (6), from which the closed latch (5) begins to protrude over the upper side of the needle stem (6).
3. Latch needle according to claim 1 or 2, characterised in that the recess (30) ends at least approximately at the position of the needle stem (6) which lies opposite the tip of the closed latch (5).
4. Latch needle according to one of the claims 1 to 3, characterised in that the angle of the rising chamfer (31) to the horizontal is at least approximately equal to the angle between the upper side (52) of the closed latch (5) and the horizontal.
5. Latch needle according to one of the claims 1 to 4, characterised in that the straight section (32) of the recess (30) runs at least approximately parallel to the underside of the needle stem (6) before the recess (30).
6. Latch needle according to one of the claims 1 to 5, characterised in that the falling chamfer (33) of the recess (30) runs at least approximately tangential to the outer contour of the needle hook (2).
7. Latch needle according to one of the claims 1 to 6, characterised in that the falling chamfer (33) of the recess (30) runs at least approximately parallel to the internal contour of the needle hook (2).

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