DE20110162U1 - Twine binders - Google Patents

Description

Gamknoter

The invention relates to a yarn knotter of the type corresponding to the preamble of claim 1.

Such yarn knotters have long been known under the name "System McCormick" and are described in the book "Landmaschinenlehre Volume II" by Prof. Dr.-Ing. Heinrich Heyde (editor) VEB Verlag Technik Berlin, Berlin 1965 on pages 128 to 131.

Such yarn knotters or twine knotters are used in baling presses for straw, hay and similar goods, as well as in the recycling of recyclable materials, e.g. for bundling paper, textiles, thin sheets of metal and the like. The twine knotter is also used in binding machines for binding small bundles of stem-like material with twine. Stem-like material is primarily understood to mean agricultural or horticultural binding material such as leeks, onion shoots, grafting stocks, flowers, individual plants with their branches such as rose bushes and the like. Such binding machines or binding devices can also be part of packaging systems for tying packs, bales or bundles made of suitable materials.

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D@KPSK.de

In stationary or mobile presses, the material to be pressed is stuffed into a press channel with a rectangular cross-section. Cuboid-shaped packages, also known as bales, are separated from the compressed material strand with a rectangular cross-section. These are surrounded by bale twine in planes parallel to the channel direction, which is knotted to form a closed binding before the bale is ejected from the press channel. In the case of built-in single knotters, the twine strand is separated from the knot and clamped for the next binding. When using double knotters, two twine strands are only clamped in the period between the formation of the first and second knot. The knotting, cutting and clamping processes are carried out by the twine knotters.

Depending on the width of the cuboid bale and the pressure prevailing in it, one or more twine knotters are arranged next to each other in a press on

a common drive shaft. The number of knotters and the press elements that feed the twine strands, namely the so-called press needles, are determined by the number of times a bale needs to be tied.
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The drive shaft is located either above or below the essentially horizontally arranged press channel; if the press channel is in another position, the drive shaft is arranged laterally.

In the case of a single knotter, the press needle guides the twine strand required for tying and knotting the bale behind the cuboid bale divided by the press piston moving back and forth in the longitudinal direction of the press channel to the twine knotter. There, the twine strand is laid over the tongue of the knotter hook and transported further to the twine clamping device. From the latter, the end of the aforementioned twine strand runs over the knotter tongue to a deflection edge of the knife lever and further around the entire bale. If double knotters are installed, both the one above the top and the one along the

The twine strand section running along the underside of a bale is transported from the press needle over the tongue of the knotting hook into the twine clamping device.

In binding machines of the type mentioned above, the material to be tied is placed on a work table, which can be arranged either horizontally or at an angle, to form a bundle. A sickle-shaped binding needle guides the twine strand around the bundled material in such a way that the twine end, which is held in the knotter, meets the twine strand placed around the bundle in the knotter for knotting.

In order to create a complete and durable knot, it is a prerequisite that before the knotting process is started, the knotting tongue, which is pivotably arranged on the knotting hook and which together with the hook part of the knotting hook forms the so-called knotting mouth, rests firmly on the hook part of the knotting hook or, in other words: the knotting mouth must be closed. To do this, a spring-loaded closer presses on a tongue roller that is rotatably mounted at the rear end of the knotting tongue. When the knotting hook rotates once to form the knot loops, the roller of the knotting tongue is guided over a curved track so that the initially closed knotting mouth is opened so wide shortly before the end of the hook rotation that the two strands of yarn stretched between the yarn holder and the knotting hook are inserted into the knotting mouth. After the hook has rotated 360°, the hook mouth is closed again. The two aforementioned yarn strands are cut by the knife attached to the knife lever, and the knot loops formed by the knotting hook are pulled over the severed yarn strand ends by the stripping comb of the knife lever. This creates a knotted structure that takes on its final shape - a firm, tightened knot - after the stripping process has ended and a tensile force is applied, which emanates from the material being pressed or tied, which is trying to expand again.

The adjustable contact pressure with which the closer applies the tongue roller varies depending on the bale weight and thus also the thickness of the required baling twine. Furthermore, the designs of the knotting hook, the knotting tongue and the associated tongue roller vary depending on the twine thickness.

As already mentioned, shortly before the knotting hook begins to rotate, the two strands of yarn to be knotted are on the tongue of the knotting hook. This contact pressure and the pressure of the closer on the tongue roller keep the knotting mouth closed. Closing pressure is also constantly exerted on the knotting mouth while the knotting hook is rotating.

However, if the closing pressure exerted by the twine strands is removed, the knotter mouth opens as soon as the knotter hook begins to rotate, depending on the weight of the pivoting knotter tongue and the tongue roller and the position of the knotter in the press or binding device. The tongue roller then slides out of the guide track of the closer and, in the worst case, can become jammed between the curved track of the knotter frame and the closer, causing significant damage to both the knotter tongue and the components for driving the knotter hook. Such a situation occurs when twine spools are used up or twine strands are torn and, as a result, the twine supply to the knotter is interrupted. Malfunctions of this kind are often not noticed immediately by the operating personnel.

The object of the invention is therefore to design a generic twine knotter in such a way that the described disturbance is avoided.

This object is solved by the invention set out in claim 1.

The invention makes it possible to exert a closing pressure on the hook mouth, even when there are no twine strands and in any installation position of the knotter, which is at least high enough to ensure that the knotter mouth remains closed in any position of the knotter hook.
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It should be noted that the invention does not involve the forces that keep the knotter mouth closed during the knotting process, but rather additional forces or an additional torque that is present in addition to the usual means that act on the rear end of the knotting tongue. Since the available dimensions in the area of the knotting hook are limited, the additional load on the knotting tongue brought about by the invention is far from sufficient to clamp the knot loops in the knotter mouth. Therefore, the installation of a suitable closer must not be dispensed with.

From DE 28 26 904 C2 it is known to apply a torque to the knotting tongue, which acts to close it, by means of a spring-loaded pin which presses on the outside of the pivot point. However, this is a different type of knotting system in which there is no actual closer and the torque required to close the knotting tongue when tying is itself applied by the spring-loaded pin.

In US-PS 3 301 583, a compression spring is also housed in the shaft of the knotting hook, which acts on the knotting tongue. However, the direction of the force intersects exactly with the pivot axis of the knotting tongue. The knotting tongue has an elongated hole through which the pivot axis passes and can move slightly in this hole against the spring effect in order to be able to handle yarns of different thicknesses. The subject matter of US-PS 3 301 583 is not directed at exerting a torque.

The means for exerting a torque may comprise, according to claim 2, a spring arrangement formed by a helical compression spring

which presses outwardly of the pivot axis onto the knotting tongue (claim 3).

An alternative embodiment according to claim 4 consists in a wire spring which surrounds the pivot axis and is ring-shaped or bow-shaped and which engages with its two free ends on the knotting hook or the knotting tongue.

The drawing shows embodiments of the invention.
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Fig. 1 shows a side view of a knotter shaft mounted

arranged twine knotters, seen in the direction of the knotter shaft;

Fig. 2 shows a perspective view of the actual knotting process.

direction;

Fig. 3 shows a view of a knotting hook of the state of the art

nik;

Fig. 4 and 5 show corresponding views according to the invention

tied knotter hook.

Fig. 1 shows the upper wall 1 of a press channel 2 through which the compacted material to be pressed, e.g. straw, is conveyed in the direction of arrow 3. Above the press channel 2, at a distance above the upper wall 1, a knotting shaft 4 extending across the width of the press channel 2 is mounted so as to be rotatable about its axis A, on which, depending on the width of the press channel 2, two to six twine knotters 10 are arranged. Each twine knotter 10 is assigned a binding twine loop laid in a vertical longitudinal plane around the pressed bale, which in the embodiment of Fig. 1 is closed by the formation of two knots, which are produced by the twine knotter 10. From the front side of the pressed bale leading in the conveying direction 3, the twine comes over the top of the press channel 2.

bale, which is held taut by means not shown, arranged to the left of the twine knotter 10 in Fig. 1. The press needle 6 guides a further strand 7 of the binding twine up from below around the rear end of the pressed bale in the direction of arrow 8, so that the strand 7 can be brought together with the strand 5 in the area of the twine knotter 10 and knotted.

The twine knotter 10 comprises a knotting hook 9 which is rotatable in the knotting frame 11 about an axis B which is directed radially to the knotting shaft 4 and obliquely upwards as shown in Fig. 1 and which can be driven about this axis B via a pinion 12.

A knife 13 is arranged to be movable transversely to the strands 5 and 7 of the binding twine in order to cut the twine after the knot has been formed. The knife 13 is attached to a knife lever 14, the shaft pin 15 of which can be pivoted about the axis E in a bearing in the knotting frame 11 and is moved by a roller 16 which moves in a groove 17 of the knotting disk, designated as a whole by 20.

18 is the twine holder which holds the strands 5 and 7 in position during certain operations of the knotting hook 9 and the knife 13 and which can be rotated about an axis D inclined forwards at approximately 45° in a vertical plane. The twine holder 18 comprises the actual holder 18A and the driver 18B, which is guided with its shaft in a bearing in the knotting frame 11. The drive is via a pinion 19 which engages with a worm 21 which can be driven by a pinion 22. The worm 21 is located at one end of a pinion shaft 38 with the axis C, at the other end of which the pinion 22 is attached.

In knotters that only create one knot per rotation of the knotter drive disk, the pinions 12 and 22 are each driven by a toothed segment on the knotter disk. The tying process is described in detail in EP 0 237 771.

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However, in the case of knotters which, in the embodiment, create two knots with one rotation of the knotting disk, the pinions 12 and 22 are driven by pairs of toothed segments 23, 24 and 25, 26 respectively, which are arranged on the flat side of the knotting disk 20 facing the viewer in Fig. 1 in the area of its outer edge. The toothed segments 24, 26 are identical to one another and are located radially somewhat further inwards, so that when the knotting disk 20 rotates they can only engage with the pinion 22. The toothed segments 23, 25 are also identical to one another and are located radially on the very outside and drive the pinion 12.

The tooth segments 25, 26 also follow the tooth segments 23, 24 when the knotting disk 20 rotates counterclockwise by an angle α of approximately 115° in the circumferential direction. The tooth segments 23, 25 extend over an angle β of approximately 30°, the tooth segment set 24, 26 over an angle γ of approximately 40°.

The knotter 10 shown in Fig. 1 performs two knots in rapid succession during one rotation of the knotter disk 20 - driven by the toothed segments 23, 24 and 25, 26, respectively, namely the first, which connects the strand 7 coming up behind the rear end of a bale to the upper strand 5 and thereby forms a closed binding twine loop, and a second, which connects the strand coming up on the front end of the following bale to the strand running on the top of the following bale and thereby initiates the formation of a new binding twine loop for the new bale to be formed. The binding twine is severed between the knots so that the successive bales are separated from one another.

From the illustration in Fig. 2 it can be seen that a second pinion 31 cooperates with the worm 21, on the shaft of which a spring cam 32 is arranged at the other end, which periodically and flexibly exerts pressure on the holder 18A so that the latter is pressed more firmly into the driver 18B and holds the yarn particularly firmly.

On the front side of the knotting frame 11 as shown in Fig. 2, the so-called closer 33 is arranged, which is designed as an elongated part and is loosely held at one end on a pin 34 sitting in the knotting frame 11. Approximately in the middle, the closer is penetrated by a screw 35 which presses the closer 33 against the knotting frame 11 from the outside via a helical compression spring 36. The free end of the closer 33 has a track on the side facing away from the viewer in Fig. 2, against which the tongue roller 50 comes to rest when the knotting hook 9 rotates about the axis B. The force of the spring 36 causes the knotting tongue 44 to be pressed firmly against the hook part 41 of the knotting hook 9 in the phase in which the tongue roller 50 is in contact, and the knotting mouth 53 (Fig. 3) is held particularly firmly closed.

Fig. 3 shows a prior art knotting hook 9 in detail. It comprises a cylindrical shaft 40 with axis B, on which it is rotatably mounted in the knotting frame 11 (Fig. 1). The actual hook part 41, which extends approximately in the direction of line 42 perpendicular to axis B, is firmly connected to shaft 40. The pivot pin 43, which extends perpendicular to the plane determined by axis B and direction 42, is arranged approximately in the area of the bend. The knotting hook 9 has an inner recess through which the knotting tongue 44 extends, which is designed as a two-armed lever, the front tongue part 45 of which extends approximately in the direction 46 parallel to direction 42 over the hook part 41 of the knotting hook 9 and the rear tongue part 47 of which runs approximately in direction 48, which forms an angle α with direction 46. of about 120°. At the rear end of the tongue part 47, a tongue roller 50 is rotatable about an axis 49 forming a small angle with the direction 48, on which the closer 33 described in connection with Fig. 2 acts, which is under the effect of the elastic force in the form of the spring 36, which is only indicated schematically here, and ensures that in certain phases of the knot formation, a torque directed counterclockwise as shown in Fig. 3 is exerted on the knotting tongue 44,

under which the knotting mouth 53 formed by the hook part 41 and the tongue part 45 is kept closed against the forces exerted by the yarn strands 54.

With regard to the features described above, the embodiments of Figs. 4 and 5 correspond to those of Fig. 3. However, further features are shown in Figs. 4 and 5 which represent means for exerting an additional torque on the knotting tongue 44, which keep it closed even when the closer 33 is not effective on the knotting roller 50.

The knotting hook of Fig. 4, designated as a whole with 9', has in its cylindrical shaft 40' a concentric bore 55 in which a helical compression spring 56 is arranged, which exerts a pressure from above on the knotting hook tongue 44 at a point offset by the distance 57 against the tip of the knotting hook tongue 44 and applies a limited torque acting on the knotting mouth 53, which is shown open in Fig. 4.

In the knotting hook of Fig. 5, designated as a whole with 9", this torque is generated by a steel wire ring 60 surrounding the pivot pin 43, which is bent by almost 360° and crosses over at its ends. At the free ends, the steel wire ring 60 has angled portions 58, 59 running perpendicular to the plane of the drawing in Fig. 5, which engage in holes in the knotting tongue 44 or the hook part 41. In Fig. 5, the knotting mouth 53 is shown closed. A ring 61 with a circumferential groove is arranged on the pivot pin 43, in which the steel wire spring 60 engages and in which it is guided.

The tongue roller 50 works in the usual way with the closer 33 on the knotting hooks 9' and 9", which is still present to apply a phased increased closing force to the knotting tongue 44 (Fig. 2). The additional means in the form of the springs 56 and 60

However, they also exert a torque on the knotting tongue 44 aimed at closing the knotting mouth 53 in those rotational positions of the knotting hook 9 in which the closer 33 is not effective on the tongue roller 50.

Claims (4)

1. Twine knotter ( 10 ) for balers,
with a knotting frame ( 11 ),
with a knotting hook ( 9 ', 9 ") rotatably mounted on a knotting hook shaft ( 40 ) forming a pivot in the knotting frame ( 11 ) with a hook part ( 41 ) projecting laterally from the knotting hook shaft ( 40 ),
with a knotting tongue ( 44 ) which is pivotably mounted on the knotting hook ( 9 ', 9 ") about a pivot pin ( 43 ) extending perpendicular to the plane formed by the knotting hook shaft ( 40 ) and the hook part ( 41 ) and is designed as a two-armed lever ( 45 , 47 ), one arm of which forms the tongue part ( 45) which interacts with the hook part (41 ) to form the knotting mouth ( 53 ) and in whose other arm ( 47 ) a force acting on closing the knotting mouth ( 53 ) can be introduced by a closer ( 33 ) in a certain rotation angle range of the knotting hook shaft 40 ,
characterized ,
that additional means are provided for exerting a torque on the knotting tongue ( 44 ) acting on closing the knotting mouth ( 53 ). 2. Twine knotter ( 10 ) according to claim 1, characterized in that the means comprise a spring arrangement. 3. Twine knotter ( 10 ) according to claim 2, characterized in that the spring arrangement comprises a helical compression spring ( 56 ) arranged in a bore ( 55 ) of the knotter hook shaft ( 40 ) extending at least substantially in the longitudinal direction of the latter, which presses outwardly of the pivot pin ( 43 ) onto the knotting tongue ( 44 ). 4. Twine knotter ( 10 ) according to claim 2, characterized in that a wire spring ( 60 ) is provided which engages the knotter hook part ( 41 ) and the knotting tongue ( 44 ) and surrounds the pivot pin ( 43 ) of the knotting tongue ( 44 ).