EP1908871A1 - Looper for tufting machine - Google Patents

Abstract

A carpet tufting machine has a grip (4) with a cutting edge incorporating a cavity (39) and a separate pusher-socket (3). The cavity (39) holds a cutter edge insert (38) that engages with a pusher co-located with a pusher chamber. The tufting machine grip has a longitudinal slide located within a socket slit. The slit extends from the narrow lower face (12) of the grip into the grip body (4). The skit is defined by two sidewalls (19, 20) or alternatively by a single thin wall (20). A cutting blade socket is located above the slide chamber extending from the flat side (9) into the grip body (4). A longitudinal crosspiece is located between the blade chamber and slide chamber.

Description

The invention relates to a gripper for a tufting machine, in particular a tufting machine, with the optional product with Schlingenflor or Schneidflor is to produce.

Tufting machines are known. They serve, for example, the carpet production. For this they have a table, over which the carrier material (so-called backing) of the later carpet is moved. Above it, a needle bar is arranged with needles, each having an eye through which a pile thread passes. This pile thread is stung again and again through the backing by rhythmic vertical movement of the bar, which is moved between the individual stitches. Below the backing is a barre arranged with rapier modules. Their grippers hold the forming Florfadenschlingen the return stroke of the needle bar. There are grippers are known which cut the formed thread loop in a later step, respectively in cooperation with a knife to produce so-called Schneidflor. From practice, it is known to provide on the gripper body a carbide insert, which has a cooperating with the knife cutting edge. If the gripper also contains a slide to selectively switch from loop pile to cutting pile and vice versa, the juxtaposition of slide and carbide insert results in a relatively large gripper thickness. This can not be reduced arbitrarily, because for the carbide insert a minimum thickness must be provided well above 1 mm.

However, it is desirable to carpets whose loops or rows of threads have small distances.

On this basis, it is an object of the invention to provide a gripper and a gripper module, on the one hand allows the switching of Schneidflor on Schlingenflor and on the other hand, with high durability allows the production of carpets with close succession loops or pile rows.

This object is achieved with the gripper according to claim 1:

The gripper according to the invention has a gripper body with two receiving spaces, namely a cutting edge insert receiving space and a slide receiving space, which are arranged separately from each other. In a preferred gripper installation position, in which the backing runs horizontally or substantially horizontally, the slider receiving space and the cutting edge insert receiving space are not arranged side by side on top of each other. As a result, the individual grippers can be made very slim. Their thickness need only be slightly greater than the minimum thickness of the cutting edge insert. Due to the slenderness of the individual grippers they can be put together in a gripper module to a gripper group with very narrow pitch. In particular, the application is possible at a pitch of less than 1/10 inch. An inventive gripper module has connection means to the gripper bar according to the prior art, so that it can be used in existing machines.

Furthermore, the separation of the two receiving spaces ensures that the slider and the cutting edge insert do not touch each other. The slider is preferably surrounded by the material of the gripper body and optionally a closure strip. On tolerances of the cutting insert, it does not matter in terms of precision of the leadership of the slider. Preferably, a web of the gripper body separates the slider from the cutting edge insert.

The slider-receiving space is preferably formed by a deep groove which is inserted into a narrow side of the gripper body. The groove guides the slider with little play and thus precise. In the production of a module are no additional measures to ensure the guidance of the slider, such as the use of guide plates required. The slot width and the gripper body width can be adapted to requirements and circumstances.

The slider has at one end means according to the prior art, so that it is longitudinally displaceable by known actuators on existing machines. So it is possible that the gripper or the module are installed in existing machines, without these would have to be changed.

In order for the slider, which is formed in a receiving space, which is arranged vertically separated from the receiving space of the cutting edge insert, with one end of the gripper body on which a nose forms a closed thread space, the slider tip is formed offset. In order to achieve an accurate cover between the slider tip and the nose of the gripper body, the slider tip can be additionally curved.

For assembly and disassembly of the slider may be formed in two parts. As a coupling between the front part of the slide, which comes into contact with the thread and the rear part of the slide, which is in communication with an actuator, such as a pneumatic cylinder, comes any form-fitting means into consideration. For example, the two slide parts are positively connected with each other, in which on a slide part a disk head is formed, which is associated with a recess on the other slide part. The

The slider receiving space may be covered by a closure strip. Thus, the gripper, consisting of gripper body, cutting edge insert, slide and closure strip can be cast in a module without potting material penetrates into the slide-receiving space.

The cutting edge insert may be made of cemented carbide, ceramic or other suitable material to form a permanent cutting edge. Its cutting edge cooperates with the cutting edge of a knife for the production of Schneidflor. For attachment of the cutting edge insert in the cutting edge receiving space, the snow edge insert may be glued, soldered, welded, caulked, crimped or otherwise connected to the gripper body.

Further details of advantageous embodiments will become apparent from the drawings, the description or claims. The figures of the drawing illustrate embodiments of the gripper according to the invention and its components. It is limited to the explanation of the essential aspects of the invention and other circumstances. It is clear that modifications are possible. Smaller, not described details, the expert can refer to the drawings in the usual way, which supplement the description of the figures.

Fig.1

ein erfindungsgemäßes Greifermodul mit mehreren Greifern für eine Greiferbarre einer Tuftingmaschine, in perspektivischer Darstellung,

Fig.2

einen Greiferkörper des Greifermoduls nach Fig.1, in perspektivischer Ansicht,

Fig.2a

einen Querschnitt des Greiferkörper nach Fig.2,

Fig.3

einen Schieber für den Greiferkörper nach Fig.2, in perspektivischer Ansicht,

Fig.4

eine Verschlussleiste für den Greiferkörper nach Fig.2, in perspektivischer Darstellung,

Fig.5

die Verschlussleiste nach Fig.4, in einer anderen Größe und einer anderen Perspektivdarstellung,

Fig.6

einen Greiferkörper mit Schneidkanteneinsatz und zugeordnetem Messer, in Seitenansicht,

Fig.7

den Greiferkörper nach Fig.6, in einer Draufsicht, und

Fig.8

eine abgewandelte Ausführungsform des Greiferkörpers nach Fig.2, in perspektivischer Darstellung.

The drawings below are not to scale, the elements of the gripper can be illustrated in different sizes in the drawings for clarity. Show it:

Fig.1

an inventive gripper module with a plurality of grippers for a gripper bar of a tufting machine, in perspective view,

Fig.2

a gripper body of the gripper module according to Fig.1, in perspective view,

2a

a cross section of the gripper body according to Fig.2,

Figure 3

a slider for the gripper body according to Fig.2, in perspective view,

Figure 4

a closure strip for the gripper body according to Fig.2, in perspective view,

Figure 5

the closure strip of Figure 4, in a different size and a different perspective view,

Figure 6

a gripper body with cutting edge insert and associated knife, in side view,

Figure 7

the gripper body of Figure 6, in a plan view, and

Figure 8

a modified embodiment of the gripper body of Figure 2, in perspective view.

FIG. 1 illustrates a module 1 which has a plurality of mutually identically designed grippers 3 held in a block 2. The grippers 3 are inserted into the block 2, for example. Poured, glued or otherwise secured in the body of the block 2. The block 2 is used for storage and support of the gripper 3 and for fixing the same to a gripper bar of a tufting machine. It is made of a suitable metal (e.g., aluminum alloy, zinc alloy, tin alloy) or plastic.

Figures 2, 3 and 4 show an overall exploded perspective view of the gripper 3. The gripper has a gripper body 4 according to FIG. 2 made of steel, for example, which is formed by a flat part with a substantially rectangular cross section. The flat part has a rear slender end 5 for storage in the block 2 and a front, if necessary, laterally cranked end 6 with a point 7 serving to grasp slings. Between the rear end 5 and the front end 6 is provided a side view approximately rectangular portion 8, which, as Figure 1 shows, in part protrudes from the block 2 in use. Two flat sides 9, 10 and two narrow sides 11, 12 delimit the section 8. The flat sides 9, 10 and the narrow sides 11, 12 thereby define the rectangular cross-section 13 indicated in FIG. 2a at the side. The flat sides 9, 10 extend over the ends 5, 6 and are preferably substantially flat, if necessary. Apart from a crank at the end 6 and the top 7. The narrow sides 11, 12 follow the contour of the gripper and are partially planar , In the transition from the end 6 to the section 8 is in the narrow side 12 a Provided step 14, so that, as is apparent from Figure 1, the section 8 extends much further down than the horizontally oriented end 6. This can be provided at the top 7 with a slightly downwardly extending nose 15.

The section 8 is provided starting from its narrow side 12 with a slot 16 which forms a slide receiving space 17 for a separately illustrated in Figure 3 slider 18. The slider-receiving space 17 is bounded by two narrow walls 19, 20, which are oriented parallel to each other. The slot 16 formed therebetween has such a width that the slider 18 can move smoothly therein. The slot 16 has a slot bottom, which is spaced in the use position to the lower narrow side of the end 6. Between slide 18 and end 6 of the gripper body 4, a thread space 21 is formed in use, as can be seen in FIG.

The slider 18 is preferably formed in two parts. It has a front slide part 22 and a rear slide part 23, which are connected to one another via a positive coupling 24. The front slider part 22 and the rear slider part 23 are preferably flat parts made of the same thickness steel or other suitable material. They have a cross-section whose width in the distance between the walls 19, 20, ie the width of the slide-receiving space 17 corresponds and whose height is slightly less than the depth of the slot 16. The slider 18 thus has two flat sides 25, 26 and two narrow sides 27, 28, each extending over almost the entire length of the slider 18. At one end, the Slider 18 with a connection 29 for an actuator, for example, be provided an actuating cylinder. The connection may be formed by a recess, a hole or the like. At its other end 30, it has a cranked tip 31. This can be doubly cranked by one hand has a to the top 7 of the gripper body 4 protruding portion and is offset to the other against the median plane of the remaining slider 18. By the tip 7 of the gripper body 4 protruding portion of the slider tip 31 has the Narrow 27 a step 41 on. The tip 7 can also be correspondingly offset against this center plane, whereby the tip 31 and the nose 15, as shown in FIG. 1, can be in close proximity or abut each other. The lateral offset of the slider 18 is used to adapt to the, as shown in Figure 7, asymmetric arrangement of the tip 7 at the end 3 of the gripper body 4th

To the gripper 3 also includes a illustrated in Figure 4 closure strip 32, whose length corresponds approximately to the length of the section 8 and which serves to close the slot 16. The straight-formed closure strip has a rib-like projection 33 which fits into the slot 16 and closes it. The projection 33 is located opposite the bottom of the slot 16 and guides the slider 18 on its narrow side 28, while the narrow side 27 slides on the bottom of the slot 16. The thickness of the closure strip 32 preferably corresponds to the distance measured between the flat side 9 and the flat side 10 of the section 8.

FIG. 5 illustrates that the locking bar 32 is provided at a front end with a chamfer which deflects the knife 34 is provided. This chamfer serves to keep a knife of an adjacent gripper away from the gripper body 4 and in particular from the narrow edges of the slot 16.

In the projection 33 or on this, a spring, for example. A leaf spring, be provided to support the slide 18 in the slot 16 without play. Alternatively, the slider 18 or the slot bottom may be provided with a corresponding spring.

As FIG. 6 illustrates, the gripper 3 is associated with a knife 35, which cuts yarn loops which are received by the yarn space 21 in order to produce pile fabric. The knife 35 has on its front side a cutting edge 36, which 'cooperates with a cutting edge insert 38. The cutting edge insert 38 is preferably formed of cemented carbide or other suitable material. At the end, it has a cutting edge 37 in order to improve the cutting of the thread loops in cooperation with the knife 35 and its cutting edge 36. The cutting edge insert 38 is received by a cutting edge receiving space 39 of the rapier body 4. The cutting insert receiving space 39 is preferably introduced into the flat side 9 of the gripper body 4 as a shallow depression. This recess is open to the flat side 9. It extends over the step 14 and receives the correspondingly shaped cutting edge insert 38 with the cutting edge 37. The cutting edge insert 38 may be glued, soldered or otherwise secured thereto in the cutting edge insert receiving space 39.

As can be seen, the cutting edge insert receiving space 39 and the slider receiving space 17 are accommodated in the gripper body 4 while not touching each other. Rather, they are separated from each other by a web 40 and arranged one above the other with respect to the vertical installation direction. As a result, on the one hand the cutting edge insert 38 have a relatively large thickness and on the other hand, the gripper body 4 are made very narrow. In particular, when the cutting edge insert 38 is made of a relatively brittle material, such as e.g. Cemented carbide or ceramic, it can easily the required minimum thickness of e.g. 1.3 mm. On the other hand, the gripper body 4 can be made so narrow that pitches of less than 1/10 inch (2.5 mm) can be achieved without problems.

The operation of the gripper 3 or module 1 is as follows:

In the tufting process, the module 1 serves to grasp the loops formed under the backing. In a first mode of operation, one or more sliders 18 are transferred to a rearward position. Therefore, the loops reach the end 6 and ultimately run over the cutting edge 37. In time with the working movement, the knife 35 comes up and moves with its cutting edge 36 past the cutting edge 37 of the cutting edge insert 38. Due to the resulting shearing the seated on the end 6 sling is cut. It is formed Schneidflor. The blade 35 brushes over only the cutting edge insert 38 and thus over material with uniform wear resistance properties. It preferably does not overflow Material of the gripper body 4. The wear remains the same,

If Schlingenflor be prepared, the respective slide 18 are transferred to an advanced position. The loops formed under the backing are now taken up with the tip 31 of the respective slider and released again on the return stroke of the module 1. You will not get into the trained from knife 35 and cutting edge insert 38 cutting.

Fig. 8 illustrates a modified embodiment of the gripper 3 based on a gripper body 4 'and its cutting edge insert 38. As far as with the above-described gripper 3 agreement is made, reference is made to the previous description with reference to the same reference numerals.

In contrast to the previous gripper body 4, the gripper body 4 'as a slide-receiving space 17. A recess which is open both in the direction of the flat side 9 and to the narrow side 12. The gripper body 4 'thus has only one wall, namely the wall 20, but not the wall 19. Accordingly, if necessary, somewhat thicker slides can be used, as may be covered by an L-shaped angle plate or the same means when pouring into the block 2.

The new gripper concept provides a gripper 3 for tufting machines, which has a slide 18 mounted longitudinally displaceable. This is arranged in a slide receiving space 17, which is preferably designed as a slot. The slot extends from the bottom Narrow side 12 of the gripper body 4 forth in this. It is bounded by two thin walls 19, 20 or alternatively by only one thin wall 20. Above the slider receiving space 17, a cutting edge insert receiving space 39 is provided, which is recessed into the gripper body 4 from the flat side 9 ago. Between the cutting edge insert receiving space 39 and the slider receiving space 17, a preferably extending in the longitudinal direction of the gripper body 4 web 40 is provided, which separates the receiving spaces 39, 17 from each other. This concept is suitable for creating very narrow gripper 3, which allow a division of less than 1/10 inch.

LIST OF REFERENCE NUMBERS

1

module

2

block

3

grab

4

Gripper body 4 '

5

The End

6

The End

7

top

8th

section

9

flat side

10

flat side

11

narrow side

12

narrow side

13

cross-section

14

step

15

nose

16

slot

17

Slider receiving space

18

pusher

19

wall

20

wall

21

thread space

22

slide part

23

slide part

24

clutch

25

flat side

26

flat side

27

narrow side

28

narrow side

29

connection

30

The End

31

top

32

sealing strip

33

head Start

34

chamfer

35

knife

36

cutting edge

37

cutting edge

38

Cutting edge insert

39

Cutting edge insert receiving space

40

web

41

step

Claims (12)

Gripper (3) for a tufting machine,
a gripper body (4, 4 ') having a cutting edge insert receiving space (39) and a slider receiving space (17) separated from the cutting edge insert receiving space (39),
a cutting edge insert (38) disposed in the cutting edge insert receiving space (39), and
with a slider (18) disposed in the slider accommodating space (17). Gripper according to claim 1, characterized in that the slider-receiving space (17) of the cutting edge insert receiving space (39) by a web (40) of the gripper body (4, 4 ') is separated. Gripper according to claim 1, characterized in that the gripper body (4) has two flat sides (9, 10) and two narrow sides (11, 12) defining a rectangular cross-section (13) of the gripper body (3). Gripper according to claim 3, characterized in that the slide-receiving space (17) of the gripper body (4) on the narrow side (12) thereof is open. Gripper according to claim 1, characterized in that the gripper body (4) is associated with a closure strip (32) for the slide-receiving space (17). Gripper according to claim 3, characterized in that the slide-receiving space (17) of the gripper body (4) on the flat side (9) thereof is open. Gripper according to claim 3, characterized in that the cutting edge insert receiving space (39) of the gripper body (4) on the flat side (9) thereof is open. Gripper according to claim 1, characterized in that the slide (18) in the slide receiving space (17) of the gripper body (4) is displaceably mounted. Gripper according to claim 1, characterized in that the slider (18) and the cutting edge insert (38) in the gripper body (4) are held without mutual contact. Gripper according to claim 1, characterized in that the cutting edge insert (38) consists of a hard metal. Gripper according to claim 1, characterized in that the cutting edge insert (38) consists of ceramic. Gripper according to claim 1, characterized in that the slide (18) is constructed in two parts and has a coupling device (24) which is in use is preferably arranged in the slide receiving space (17).

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