EP1747996B1 - Closure device for clips - Google Patents

Description

The invention relates to a closure arrangement according to the preamble of the independent claim.

It is known to seal packaging by metal clips, such packaging being, for example, sausage-shaped packages emerging from a filling machine and provided with clips by the closure assembly. In the formation of sausages, which emerge as a continuous, tubular product from a filling machine, the closure assembly usually on displacement shears, which form the constriction between the end of a sausage and the beginning of the next sausage, at which constriction of the clip for the End of a sausage and the clip is set for the beginning of the next sausage. The clips are thereby cut from a continuous, preformed open clips adjoining each other forming clip wire, which is usually held in roll form on the Verschliessanordnung, when setting the clip and deformed to the closed clip. Such is eg off DE-A-40 13 033 known.

The object of the present invention is to improve a closure arrangement for closure clips.

This object is achieved with the closure arrangements according to claim 1. The fact that the feed lever on the drive side tool-free solvable and refastenable reduces the service life of the arrangement when changing the feed lever for different clip wire widths considerably.

Because preferably the feed lever has a plastic support at its front end or feed end or is formed from plastic, or has a roller or ball, on the one hand the clip wire can be spared during feed. On the other hand, but especially the wear of the closing arrangement itself is greatly reduced when this arrangement is in idle mode without clip wire in operation, since doing the feed end the feed lever comes into contact with the clip wire guide in the feed channel. A plastic training or a rotatable role or ball-like training can significantly reduce the wear of the arrangement in this area.

The fact that a wire positioning and wire retention means is provided in the feed channel itself increases the positioning accuracy of the clip wire in the cutting and forming tool and avoids incorrect positioning due to the behavior of the wire, especially at high cadences of the arrangement.

Also concerned about good wire positioning is the adjustability of the spring force acting on the feed channel.

Another aspect is the adjustability of the die on the forearm of the closure arrangement, which allows the adjustment of the cutting clearance and thus the correct clip formation in a simple manner.

• Figur 1 eine Verschliessanordnung nach Stand der Technik;
• Figur 2 eine teilweise geschnittene Darstellung einer erfindungsgemässen Verschliessanordnung;
• Figur 3 einen Schnitt entlang von Linie A-A von Figur 2; und
• Figur 4 eine Draufsicht gemäss Pfeil X von Figur 2.

In the following, the prior art and embodiments of the invention will be explained with reference to the drawings. It shows

• FIG. 1 a closure arrangement according to the prior art;
• FIG. 2 a partially sectioned view of a closure arrangement according to the invention;
• FIG. 3 a section along line AA of FIG. 2 ; and
• FIG. 4 a plan view according to arrow X of FIG. 2 ,

FIG. 1 shows a closing arrangement 100 according to the prior art, by means of which the essential elements of a closing arrangement will be briefly explained again. Disposed on a forearm 116 of such an assembly is a die 118 which, together with a punch 117 on an upper arm 115 (shown in broken lines), forms a clip cutting and sealing tool consisting of a continuous preformed clip wire 112 and 112, respectively be formed. The clip wire feed takes place by a feed lever 113 which is rotatably mounted on a crank disk 114 and pivots in the movement in the arrow direction about the pin 119 and performs with its front free end the indicated egg-shaped movement. 113 'indicates how the front end of the feed lever engages in the clip wire and lifts it over the cutting edge of the die 118, which is indicated by the clip wire with the number 112'. Upon further movement of the feed lever, this sets the clip wire in the die, which is represented by the clip wire 112. When closing a packaging casing, in particular a sausage 104, two shears are generally used in the closing arrangement, of which only one pair of shears with its arms 102, 103 is shown. The scissors lace in a known manner in closely adjacent position, the package by a movement of the scissor arms and then move away from each other, which forms an elongated, constricted, product-free area of the packaging material (sausage casing) between the two sausages, in which then in the Usually two clips are set in succession, namely the end clip of one sausage-shaped package and the initial clip of the subsequent sausage-shaped package. Shown further in the figure are various drive elements which achieve the said movements for constricting, cutting and closing by a motor drive with chains, gears and cams. this will here, as known, not explained further. The present invention relates to such a closure arrangement as far as not explained below.

FIG. 2 now shows a more detailed, partially sectioned representation of an inventive closure arrangement, wherein in FIG. 2 only the lower arm 2 and the wire feed is shown and the punch 4 is indicated, while the other elements, in particular the shears of the closing arrangement are not shown. These work in the conventional manner and need not be further explained here. The clip wire 5 is also shown here as a preformed clip wire in the position in which it lies in the die 3 and is positioned for cutting between the cutting parts 37 and 38 of punch 4 and die 3. The feed of the clip wire is carried out with a feed lever 11 in a known manner by this is fixed to a crank disc 12, which will be explained in more detail, and rotates about the pin 16 and moves along it. It is seen that the clip wire 5 is guided in a feed channel 6 with an upper part 20, in which feed channel, the front free end of the feed lever engages from below to move the clip wire in each case by a clip division forward and in the die 3 as shown position. The clip wire 5 comes from a clip wire supply, not shown, which is usually a clip wire roller, which is rotatably supported on the Verschliessanordnung and from which the clip wire is inserted in a manner not shown in the feed channel 6. The feed channel 6 is seated on a support 7 which is rotatable about the axis 8 for lifting the feed channel and thus the clip wire 5, so that the clip wire 5 can be lifted over the blade 38 during the advance and then lowered into the die. The feed channel 6 with its carrier 7 is raised during the advance by the feed lever 11, 11 'against the force of a spring 10 and the feed of the Wire causes. The spring force on the other hand leads to lowering of the feed channel 6 and the clip wire 5 when the feed lever 11 is moved by the crank mechanism 12, 13 back down. A cutting positioning means 24 engaging outside the feed channel at the top of the clip wire is known.

The FIG. 3 shows a section through the feed drive along the line AA of FIG. 2 , Based on Figures 2 and 3 Now, a first aspect of the invention can be explained. Accordingly, the front free end of the feed lever 11, which acts on the clip wire and causes the lifting of the feed channel is formed in the example shown by a substantially U-shaped plastic cap 17, which forms the free end of the feed lever 11 and the feed end, which engages the clip wire 5. Side of this plastic cap 17, the free tongues 22 and 23 of the feed lever are visible, which, however, do not promote the wire but only form a lateral guide for this. The formation of the front, the wire conveying end of the feed lever 11 made of plastic on the one hand has the advantage that the wire over the previous purely metallic design of the feed lever during feeding is not damaged and is not provided with engagement marks. Another significant advantage is that the front part of the feed lever dips less far into the clip wire through its cap 17. The - depending on the pitch of the clip wire - deep immersion of the feed lever according to the prior art can namely lead to a temporary jamming of the front part in the wire, which interferes with its exact promotion and positioning. The main advantage, however, lies in the fact that at idle the machine without wire, which may happen at the end of the wire coil and also otherwise, the upper wire guide in the feed channel 6 is not damaged. This is in FIG. 3 and designated 21 and consists of a material to which the wire 5 in its promotion despite the force of the spring 10 easily slides along to provide as low as possible promotion even at high cadences. It is known, for example, to manufacture the upper guide 21 from bronze in order to give a good sliding behavior for an aluminum wire 5. In the embodiment of the feed lever 11 and the front end of the prior art made of metal, it comes at idle wire without a considerable wear on the guide 21 which is undesirable. This is remedied according to the first aspect of the invention, in that the plastic part 17 does not wear the guide 21 even when idling, so that its service life is substantially increased. If the plastic part 17 wears, this can be easily replaced at the top of the feed lever 11, in particular if it is merely plugged and secured by positive locking, for example by a pin. Of course, other embodiments are quite possible, the whole front part of the feed lever 11 may be integrally formed of plastic, in particular together with the tongues 22 and 23. Further embodiments are possible, for example, by the front engaging end of the feed lever 11 of a cylindrical, rotatable about its longitudinal axis Feed lever 11 arranged roll is formed, which can also engage in the wire 5 to its promotion and which rolls at low wear on the upper guide 21 wear. Instead of a roller and the provision of a front end of the feed lever 11 with a held in a holder and partially exposed ball is possible, which rolls on idle operation on the guide 21. However, the structurally simple and cost-effective solution with the plastic part 17 is preferred.

Another aspect of the invention lies in the attachment of the feed lever 11 on the crank mechanism. The feed lever must be replaced for different widths of the clip wire to be adjusted in its width also to this, due to the lateral Tongues 22 and 23 can be seen which form lateral guides for the clip wire. According to the prior art, the feed lever must be unscrewed from the driven crank pulley 12 by the threaded bearing pin of the feed lever is attached to the disc is released and is fixed again for the new feed lever. This work is complicated due to the installation position of the crank mechanism. According to the present invention, the feed lever 11 is attached to the crank mechanism so that it can be attached and detached without tools. This is possible in principle by any tool-less mountable and detachable fastening means which enables the correspondingly movable mounting of the feed lever 11 on the crank disk 12. Particularly preferred is the illustrated embodiment, in which on the crank disc 12 a protruding pin 13, 13 'is fixedly arranged. On the feed lever on the other hand, a corresponding, suitable for pin 13 clamping assembly 14 is provided, for example made of plastic, which by elastic springing around the pin 13 to a larger part of its circumference on the pin 13 'can be clipped. In other words, in an assembly movement, which presses the feed lever 11 on the pin 13, the two side parts of the attachment 14 are resiliently pressed apart, so that the pin is pressed into the correspondingly shaped recess in the holding part 14. The spread apart when pushing in side parts of the support member 14 go back to their original position and hold the feed lever rotatably on the pin 13. For disassembly, a tensile force on the feed lever is exerted in such a way that the side parts of the support member 14 spread open again, so that the pin can be solved. This type of assembly results in a very quick and easy tool-releasable mounting option. The holding member 14 may be fastened with screws on the central part of the feed lever 11, like that FIG. 3 is apparent. These In the pin 13, a circumferentially extending recess may be present, in which a corresponding shape of the retaining element 14 can engage to exact positioning in the longitudinal direction of the pin 13 to to reach.

According to a further aspect of the invention, a wire positioning and retaining means 25 is arranged in the feed channel, which prevents sliding back of the wire during and after its feed. It is known to provide a partially out of the feed channel wire holding means 24, which contacts the wire only outside the feed channel and presses against the cutting edge 38 of the die 3 to improve the cutting precision. However, it has been shown that at high cadences or wire feed speeds inaccuracies in the wire positioning and cutting may occur to which the wire holding means 24 has no significant influence. To prevent them, a positioning and retaining means is now provided, which engages in the feed channel 6 on the wire and prevents it from sliding back. This can be done because the wire roll and the preformed wire on its way to the die have a significant, in particular by the preforming induced elasticity in the feed direction, which can lead to vibrations and other effects that can affect the precise advancement by sliding back of the wire , The wire retaining means in the feed channel can effectively prevent this and improve the positioning precision of the wire and thus the good quality of the closure clip. Preferably, the wire retaining means is arranged in the feed channel in the conveying direction in front of the feed lever 11, so that the wire thus first reaches the wire retaining means and then the feed lever, as shown in the FIG. 2 is shown. Preferably the means 25 contacts the wire from below and is also arranged on the lower inside of the feed channel. The wire retaining means and positioning means 25 may be formed in any way, but it should impede the feed of the wire as little as possible, while preventing the sliding back of the wire against the feed direction as effectively as possible. A preferred construction for this is in FIG. 2 shown, in which the wire retaining means is formed by a lying on the underside of the feed channel 6 leaf-shaped spring which is fixed in the feed channel and can bend in the advance of the wire in the figure down and thus does not hinder the feed, but which springs back when it is no longer acted upon by the wire and has a front bearing surface 25 ', which prevents sliding back of the wire against the conveying direction.

Another aspect of influencing the positioning accuracy and thus the quality of the clip closure is to influence the force of the spring 10. According to the prior art, this spring force is not adjustable and is the same for all wire dimensions and cadences. According to the aspect of the invention now explained, however, the spring force is made adjustable. This can be done in a simple manner initially as shown in the figure, characterized in that the spring attached to the lower arm and the holder 7 of the feed channel is arranged at one or both of these points so that the bias of the spring can be adjusted. In the in the FIG. 2 shown embodiment, this is achieved in a simple manner such that the spring 10 is held on the forearm side to a threaded bolt 26 which is adjustable by a nut 27 so that the spring preload can be adjusted by turning the nut 27. With a lock nut this position is then fixed. In this way, for example, the spring preload when changing to another wire dimension be adjusted accordingly or adapted to increase the cadence of the clip formation. It is also possible to make this spring force adjustable during operation, on the one hand only a schematically indicated arrangement 28 is possible, which changes the spring preload adjustable by motor, so that it can be set or changed by the control of Verschliessanordnung cadence dependent. It is also conceivable to simulate the spring force in other ways, for example hydraulically or pneumatically and to change them accordingly. So if in this case is spoken by spring force, so it is also meant an equivalent force, which is generated by a different element than a spring.

Another aspect of the invention relates to the attachment of the die 3 on the forearm 2. This is done in such a way that the die 3 is displaceable in the feed direction or against the feed direction, whereby the cutting clearance x between the cutting edges 37 and 38 about 5/100 mm should be adjustable to the die 3 itself. This was not the case until now and due to the tolerances between the forearm and the upper arm supporting the punch 4, the cutting clearance often had to be very large. The adjustability of the die now gives the opportunity to adjust the cutting clearance with fully assembled closure assembly. Preferably, an eccentric pin 30 is arranged in a bore of the lower arm and rotatable there, wherein the protruding from the bore upper part of the eccentric pin 30 performs an eccentric movement. The die 3 is as in FIG. 4 can be seen, which shows a view of the forearm, on the one hand in lateral guide rails 32 and 33 of the forearm held so that they can move only in the longitudinal direction. On the other hand, the die 3 is as in FIG. 4 indicated with a transverse slot 34, in which the eccentric part of the pin 30 engages so that the die is defined defined in its position in the feed direction upon rotation of the pin 30 in its bore by the eccentric. This allows the exact adjustment of the cutting clearance by displacement of the die 3 in the final assembled Verschliessanordnung and thus the compensation of the tolerances between the forearm and upper arm. Is the cutting game set accordingly, the die 3 can be fixed by the threaded bolt 31 definitely on the forearm 2.

Claims (11)

1. Closure device (1) for packs, by means of which a closure clip is cut off by a pre-formed clip wire (5) and is deformed for closing, and in which the clip wire can be slid forward into the cutting and closing tool by a driven feed lever (11) in a feed channel (6) in the manner of a clip, and in which the feed lever is arranged on a crank assembly (12, 13) on its end facing away from the feed channel, characterised in that the feed lever can be secured to the crank assembly without a tool and is arranged releasably on it.
2. Closure device according to Claim 1, characterised in that the feed lever is secured to a pin (13) of the crank assembly by a clamping element (14) gripping this pin only partially and in an elastically resilient manner.
3. Closure device according to Claim 1 or 2, characterised in that the feed end of the feed lever provided for engaging on the clip wire is formed by a plastic part (17), a rotary element, in particular a roller, or a ball.
4. Closure device according to Claim 3, characterised in that the feed lever has at its end a recess bounded by two projecting tongues (22, 23), in which recess is arranged an essentially U-shaped plastic cap (17) which forms the end provided for engaging on the clip wire.
5. Closure device according to any one of Claims 1 to 4, characterised in that a wire retaining means (25), which counteracts a movement of the wire against the conveying direction, is arranged in the feed channel in the conveying direction, in particular in front of the feed lever and in particular on the underside of the feed channel.
6. Closure device according to Claim 5, characterised in that the wire retaining means is formed by a leaf-shaped spring (25) extending in the longitudinal direction of the feed channel and secured at one end, which spring is bent at its free end to form a contact surface for the clip wire.
7. Closure device according to any one of Claims 1 to 6, wherein the feed channel is retained in the cutting position by resilience and can be swivelled against the resilience for feeding, in particular by a feed lever, characterised in that the resilience of the spring means (10) generating the resilience is adjustable, in particular in that it is adjustable by means of an adjusting device (28) that is cadence-dependent.
8. Closure device according to Claim 7, characterised in that the resilience is generated by a tension spring (10) secured to the lower arm of the closure device and to the feed channel, wherein the fastening point of the spring is adjustable on the lower arm side and/or the feed channel side in order to adjust the pre-tension of the spring.
9. Closure device according to any one of Claims 1 to 8, in which the cutting and closing tool comprises a die (3) secured to a lower arm of the device, characterised in that the die is adjustable at the lower arm with an adjusting device so that it moves forwards and backwards in the direction of feed and can be fixed after adjustment.
10. Closure device according to Claim 9, characterised in that the adjusting device comprises a longitudinal guide (32, 33) for the die and an eccentric adjustment (30, 34) which establishes the position of the die in the longitudinal direction.
11. Closure device according to any one of Claims 1 to 10, characterised in that this device has displacing shears for forming the ends of sausage-shaped packaging materials, between which shears the feed channel is arranged.

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