EP1514964B1 - Latch needle - Google Patents

Description

The invention relates to a latch needle, in particular for knitting machines.

Knitting machines are often equipped with so-called latch needles, which have a slender, at one end a shaft forming needle body, the shaft merges at its free end into a hook. In the vicinity of the hook, a tongue slot is provided, in which a pivotally mounted tongue is arranged. This can perform a pivoting movement, wherein they the thread space of the hook opens or closes. Such latch needles are known for example from JP 61-133586. This latch needle has one of the needle breast through to the needle back continuous tongue slot in which the tongue is freely pivoted freely. In the vicinity of the tongue bearing the tongue has a blunt extension with a rounded tip.

Furthermore, from US-PS 1163296 a latch needle is known, the tongue can be moved via a provided on the needle slide. For this purpose, the tongue has at its end a recess which is associated with the tip of the slider and by means of which the tongue, if necessary, can be pushed away from the hook or the needle back.

Due to the slide projecting into the tongue slot, the tongue is only partially freely rotatable. The operation of such needles is only possible with locks that have an additional track for the slide.

Further, from JP 8-60504 a latch needle with back open slot and tongue spring is known, which interacts with the tongue. The tongue has at its spring-facing end a flattening and a cam to define two stable positions of the tongue.

All said needles are subject to contamination during operation, as a result of which a mass consisting, for example, of fiber residues, oil and dust can accumulate in the tongue slot. Such accumulations of dirt affect the function of a latch needle when they get out of hand.

It is an object of the invention to provide a latch needle that is less susceptible to contamination.

This object is achieved with a latch needle having the features of claim 1:

The latch needle according to the invention has a tongue, which is formed at its end mounted in the tongue slot as a cleaning device for the tongue slot. This is achieved by providing the tongue with a special cleaning profile. The cleaning profile serves to move during the back and forth movement of the tongue fiber remnants or other, got into the tongue slot dirt and to create it out of the tongue slot out. Thus, the mobility of the tongue can be obtained even if relatively much fiber abrasion or other dirt accumulates and enters the tongue slot.

The cleaning profile is preferably a step formed on the tongue spoon or an appendage, however, the tongue is thereby seen from the center of the tongue hole, not or not significantly extended. Preferably, the distance of the end face of the projection from the center of the tongue hole is not or not substantially greater than the distance of the flanks from the center of the tongue hole. The size ratio is preferably about 0.8 to 1.5, preferably 1.

Further preferably, the cleaning profile has at least one sharp edge which extends parallel to the tongue hole across the entire tongue width. The rounding radius of this edge is as small as possible. Thus, dirt present in the tongue slot is reliably detected and made it out of the slot. The cleaning profile also has as flat as possible with respect to the tongue hole approximately in the radial direction surface, which serves to push fiber residues or other dirt during the pivotal movement of the tongue in front of him. This surface extends to the side edges of the tongue, to which it borders with relatively sharp edges. In this way, trapping of dirt in the gap between the flanks of the tongue and the side walls of the tongue slot is avoided. The cleaning profile can be considered as a tooth profile.

The cleaning profile is preferably provided on latch needles with freely pivotally mounted tongues. Such latch needles have no means for fixing the tongue in selected layers, such as springs, slides or the like. Rather, the tongue on its journal pivot freely and friction swing back and forth, the pivoting movement is controlled by the thread and / or the movement of the latch needle itself. In this case, the tongue slot can be open on both sides, i. be formed closed from the needle breast to the needle back and closed back. In both cases, the cleaning profile of the tongue causes the tongue slot to be kept clean.

The latch needle may, if necessary, but also be provided with a spring which supports one or more selected pivotal positions of the tongue yielding. The cleaning profile may be provided here in addition to other functional profiles that interact with the spring. Regardless, the cleaning profile can keep the tongue slot clean.

Figur 1

eine Zungennadel in vereinfachter perspektivischer Darstellung,

Figur 2

die Zungennadel nach Figur 1 in einem anderen Maßstab in ausschnittsweiser Darstellung,

Figur 3

die Zungennadel in Figur 1 oder 2 in teilweise geschnittener Seitenansicht in einem anderen Maßstab,

Figur 4

eine abgewandelte Ausführungsform der Zungennadel in teilweise geschnittener Seitenansicht,

Figur 5

eine weitere Ausführungsform einer Zunge für eine Zungennadel in Perspektivdarstellung,

Fig. 6 und 7

weitere Ausführungsformen einer Zunge mit unterschiedlichen Reinigungsprofilen in Seitenansicht,

Figur 8

eine Ausführungsform einer erfindungsgemäßen Zungennadel mit Zungenfeder in einer teilweise geschnittenen Seitenansicht und

Figur 9

eine Ausführungsform einer Zungennadel mit rückseitig geschlossenem Schlitz in teilweise geschnittener Seitenansicht.

Further details of advantageous embodiments of the invention will become apparent from claims, from the drawing or the description. In the drawings, embodiments of the invention are illustrated. Show it:

FIG. 1

a latch needle in a simplified perspective view,

FIG. 2

the latch needle of Figure 1 on a different scale in a sectional view,

FIG. 3

the latch needle in Figure 1 or 2 in a partially sectioned side view on a different scale,

FIG. 4

a modified embodiment of the latch needle in a partially sectioned side view,

FIG. 5

a further embodiment of a tongue for a latch needle in perspective view,

6 and 7

further embodiments of a tongue with different cleaning profiles in side view,

FIG. 8

an embodiment of a latch needle according to the invention with tongue spring in a partially sectioned side view and

FIG. 9

an embodiment of a latch needle with closed back slot in a partially sectioned side view.

FIG. 1 illustrates a latch needle 1 which has a needle body 2 with a shaft 3 which is provided with a hook 4 at the end. The hook is associated with a tongue 5, which is pivotally mounted in a tongue slot 6 by means of a bearing device 7. As illustrated in FIG. 2, the tongue slot 6 is arranged in the immediate vicinity of the hook 4 so that the tongue 5 touches the hook 4 with its spoon 8 on the one hand and thus close a thread space and on the other hand can reach the shaft 3 in reserve.

The tongue slot 6 is bounded by two slot walls 9, 11, which the tongue 5 its flanks 12, 13 turns. In the embodiment of Figure 3, the tongue slot 6 extends from the needle top 14 to the needle back 15, i. it is open on both sides. As is also apparent from Figure 3, the tongue 5 is penetrated at a tongue hole 16 by a bearing pin 17 which forms the bearing means 7. The bearing pin 17 is arranged approximately centrally between the needle top 14 and the needle rear side 15 in the embodiment of Figure 3. The arrangement of the bearing device 7 with respect to the needle top 14 and the needle back 15 is determined by the knitting application dependent. The tongue hole 16 may be arranged in the tongue shaft end 18 centrally or off-center between tongue shaft bottom 26 and back surface 27.

The tongue end 16 provided with the end of the tongue 5 is the tongue end 18, which is provided with a cleaning profile 19. This is formed, for example, by a step 21, in which the rear end surface 22 reduces its distance to the center 23 of the tongue hole 16 abruptly. It This results in a preferably radially extending, ie oriented in the circumferential direction clearing surface 24 which connects with reasonably sharp edges of the flanks 12, 13 of the tongue 5. In addition, the reaming surface 24 preferably adjoins the end surface 22 with a reasonably sharp edge 25. In the embodiment according to FIG. 3, the clearing surface 24 faces the needle top side 14 when the tongue 5 is in the back position. The step 21 is preferably arranged in line with the tongue hole 16 and the spoon 8. The relevant line L is shown in phantom in FIG. Further, the largest distance of the end surface 22 from the center 23 (eg, measured at the location specified by the line L) coincides with the greatest distance of the tongue shank bottom 26 or the back surface 27 of the tongue 5 from the center 23. On the other hand, the step 24 is followed by a region 28 of the tongue 5 closer to the middle 23.

The tongue needle 1 described so far works as follows:

In operation, the tongue 5 is reciprocated along its longitudinal direction X. The low-friction, freely pivotally mounted tongue 5 pivots periodically from the position I shown in solid lines in Figure 3 in the position II shown in dashed lines and back. At the same time, the clearing surface 24 also pivots back and forth. It thus causes that in the tongue slot 6 dirt every time when the tongue 5 pivots from position II to position I, taken from the clearing surface 24 and moved ie taken away. The dirt in question is thus made on the needle back 15 and on the needle top 14 from the tongue slot 6 out.

In this way, the ease of movement of the tongue 5 is maintained. Due to the substantially planar design of the clearing surface 24 also prevents dirt pushed in front of the clearing surface 24 in the gap between the flanks 12, 13 and the insides of the slot walls 9, 11 is clamped.

Figure 4 illustrates a modified embodiment of the invention. Reference is made to the above description with reference to the same reference numerals. Existing differences are explained below:

The stage 21 is oriented opposite to the embodiment described above. If the tongue 5 is in the position illustrated in FIG. 4 (position I), the clearing surface 24 faces the needle back side 15. In addition, the rounding of the edge 25 is slightly larger and the reaming surface 24 is not exactly radially oriented. The area 28 of the end face 22 follows approximately a radius with respect to the center 23 of the tongue hole 16. By this measure, the effectiveness of the clearing surface 24 in the removal of dirt from the tongue slot 6 is increased. In addition, the dirt promotion takes place each time Nadel Nadelhub, i. at the transition of the tongue 5 from position I to position II instead. The dirt promotion takes place here mainly to the needle back 15.

FIG. 5 illustrates a further modified embodiment of a tongue 5 with a projection 29 provided on the end face 22 as a clearing or cleaning profile 19. The projection 29 is provided with a substantially flat end face 31 which is surrounded by sharp edges is limited. In particular, the end face 31 with a sharp edge 32 adjoins the flank 12 and with a sharp edge 33 against the flank 13. The edges can be rounded or, if necessary, also made sharp to the substantially planar reaming surfaces 24a and 24b.

The advantage of this tongue 5 lies in the clearing and cleaning action in both pivoting directions, i. both in the transition from position I to position II and vice versa.

Another embodiment of the tongue 5 is illustrated in FIG. For this embodiment, the comments on the embodiment according to Figure 5 apply accordingly. In addition, as in the examples described above, the distance AF from the back surface 27 to the center 23 is also approximately the same as the distance AE from the end surface 22 to the center 23. The ratio of AF to AE (AF / AE) is in the range of 0.8 to 1.5, preferably 1. It is AE at the farthest from the center 23 portion of the end surface 22, ie measured at the end surface 31. This can, as Figure 6 illustrates, be provided with a recess 34, which may still improve the effectiveness of cleaning.

As FIG. 7 illustrates, instead of a single step 21, it is also possible to provide a series of several steps 21a, 21b, which are oriented in the same or different direction. In the simplest case, the tongue shank bottom 26, starting from a first radius R in the region of the tongue shaft end 18 at the step 21 a on a first larger value R1 and at the step 21 b on a second even greater value R2 over. The resulting reaming surfaces 24a, 24b are preferably oriented approximately radially. The radius R increases from the tongue shank bottom 26. However, it is also possible to start the steps on the back surface 27 to produce the cleaning profile 19.

In all the above cases, the steps 21 (21a, 21b) form teeth which serve and which are adapted to grasp the dirt which has entered the tongue slot 6 and to convey it to the outside.

FIG. 8 illustrates a further modified embodiment of the latch needle 1, in which a tongue spring 35 is arranged in the latch slot 6. This cooperates with a functional profile 36 of the tongue 5, which is formed on the tongue shaft end 18 in addition to the cleaning profile 19. The functional profile 36 may be formed, for example, by a flattening, ie a plane surface or facet 37, which lies flat against the tongue spring 35, shortly before the tongue 5 comes to the complete reserve position. In this way, the tongue 5 can have a stable return position in which it does not bear completely on the shaft 3. To avoid spring damage, the edge 25 may be slightly rounded. The reaming surface 24 serves in this embodiment as described above for clearing and cleaning the tongue slot. It is formed at the step 21, in which the end surface 22 passes from a radius R1 to the radius R. Preferably, the radius R1 is slightly less than the distance of the facet 37 from the center 23rd

FIG. 9 illustrates a further embodiment of the latch needle 1 according to the invention. The difference from the above-described latch needles is that the latch slot 6 is open only at the needle top side 14, but at the needle rear side 15. It can find all the above tongues 5 application. In particular, a design of the tongue 5 according to Figure 3, 5, 7 or 9 is preferred. With particular reference to these figures, the foregoing description applies accordingly.

A latch needle 1 is provided with a tongue 5 which carries a clearing profile 19 at its tongue end 18. The broaching profile 19 serves to keep the tongue slot 6 free of dirt. It has for this purpose at least one special clearing surface 24.

LIST OF REFERENCE NUMBERS

1

latch needle

2

needle body

3

shaft

4

hook

5

tongue

6

latch slot

7

Storage facility

8th

spoon

9, 11

Diaphragm walls

12, 13

flanks

14

Needle top

15

Needle back

16

latch hole

17

pivot

18

Latch shank end

19

cleaning profile

21, 21a, 21b

step

22

end face

23

center

24

rake face

25

edge

26

Latch shank underside

27

backrest

28

Area

29

head Start

31

end face

32, 33

edge

35

latch spring

36

functional profile

37

facet

AE

distance

AF

distance

L

line

R

radius

X

longitudinal direction

I, II

positions

Claims (9)

1. Latch needle (1), in particular for knitting machines,
   with a needle body (2), which has a blade (3) provided with a hook (4) at the end, which is provided with a sawslot (6) close to the hook,
   with a latch (5), which at a sawslot end (18) is disposed to pivot in the sawslot (6) on a latch bearing means (7),
   characterised in that the latch (5) is provided with a cleaning profile (19) at the sawslot end (18), wherein the cleaning profile (19) has at least one sharp edge (25, 32, 33).
2. Latch needle according to Claim 1, characterised in that the latch (5) is disposed to pivot freely and unhindered by means of the sawslot bearing means (7).
3. Latch needle according to Claim 1, characterised in that the sawslot (6) extends from a needle upper side (14) to a needle rear side (15) and is open both at the needle upper side (14) and at the needle rear side (15).
4. Latch needle according to Claim 1, characterised in that the cleaning profile (19) is formed by a tooth profile on an end face (22) of the latch (5).
5. Latch needle according to Claim 1, characterised in that the latch (5) is guided in each pivot position exclusively by a bearing journal (17) as well as by slot walls (9, 11) of the sawslot (6).
6. Latch needle according to Claim 4, characterised in that the cleaning profile (19) includes at least one step (21) configured on the end face (22).
7. Latch needle according to Claim 4, characterised in that the cleaning profile (19) has at least one scraper face (24), which extends substantially in radial direction in relation to the bearing means (7).
8. Latch needle according to Claim 4, characterised in that the step (21) is arranged at a location on the latch (5) located opposite the latch spoon (8).
9. Latch needle according to Claim 1, characterised in that a latch spring (35), which cooperates with the latch (5), is arranged in the sawslot (6).

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