This is a 371 of PCTIEP00/00298 filed Jan. 13, 2000 (international filing date.
This invention relates to a device for printing and delivering semi-rigid labels (tags) to packaging and sealing machines such as sausage clip machines or the like, comprising a feed means for withdrawing a strand of labels from a supply and advancing the strand of labels through a printing station to a delivery station. Such labelling machine for providing webs of fabric with labels clamped onto the edge thereof is known from CH-PS 245 342.
It is furthermore known to print self-adhesive labels in connection with automatic label tapes, which are associated to machines for packaging foodstuffs, directly before delivering the labels, in order to attach information as to the expiration of the foodstuff packaged only at the packaging time relevant for the expiration date. For certain foodstuff packages self-adhesive labels are not suited because they do not adhere sufficiently for instance to moist or greasy sausage casings. For these cases it is known to incorporate label tags instead of a self-adhesive label in the means used for sealing for instance sausage ends, i.e. to in particular fix a portion of the tag together with a neck of packaging material at the package by means of a closure clip.
What is problematic in the one as in the other case is the delivery of labels to the respectively used packaging machines. There are commonly used feed rollers which have, however, the disadvantage that a slip between the roller surface and the labels can lead to a misalignment of the labels within the cycle, all the more so as because of the cyclic feed considerable accelerations and decelerations must again and again be handled. This is particularly true for label tags, which must regularly consist of a more rigid material than self-adhesive labels and already for this reason have a higher weight. The necessity of a reliable printing in the course of the delivery of the labels to the sealing machine still aggravates this problem.
From DE 24 17 225 A1 a labelling device for successive hose packages (such as sausages) is known, wherein two labels connected by a connecting thread are each cut of from a label strip and are delivered to a means for sealing adjacent packages such that the connecting thread is seized by the clips sealing on the one hand the end of the leading package and on the other hand the beginning of the succeeding package, and thereupon both the labels and the connecting thread are cut through. The feed is effected by means of a pivotally mounted double-finger arrangement, which during the feed movement grasps behind cuts in the strand of labels and during the return stroke glides over the succeeding labels. However, the labels are completely printed and cannot be provided with actual information such as expiration dates or the like at the moment of processing.
This problem should be eliminated by means of the invention. In a combined printing and delivery device as stated above it provides on the one hand that the feed means has a finger translationally moving to and fro, which during the working stroke grasps behind a shoulder of the respective label and advances the same by a defined distance, whereas during the return stroke it glides over the succeeding label, until at the end of the return stroke it grasps behind the shoulder of this succeeding label, and on the other hand that a printing and embossing roller lifted off during the working stroke is urged against the succeeding label during the return stroke and inscribes said label. This ensures that each label is exactly printed directly before being delivered to the packaging machine and that it gets into the delivery station.
Preferably, the finger has the shape of a two-prong fork which grasps behind two shoulders of the respective label aligned vertical to the feed direction. This stabilizes the translational feed and prevents any canting and thus jamming tendency. In accordance with one embodiment it is provided that during the return stroke a pin extending vertical to the label feed plane biases the succeeding label into the plane of action of the finger or fork. It is basically irrelevant whether for the working stroke the label is raised into the plane of action of the finger or fork or said finger or fork is lowered into the plane of the label. Because of the resilience of the label material it is, however, also possible to leave it at one plane and during the return stroke have the prongs of the fork elastically bend the label on both sides, so that at the end of the return stroke the label completely returns to the plane of the fork. The pin stationarily mounted in the center between the paths of the fork prongs each time urges against the front area of the succeeding label such that it reliably lifts the adjacent shoulders of the label to be fed into the delivery station into the plane of action of the fork prongs and holds them there.
Inscribing is advantageously performed such that the printing and embossing roller urges the label against a stationary printing matrix provided with adjustable sets of characters. Thus, the one stroke of the feeding means is used for advancing the strand of labels and the other stroke (return stroke) is used for printing the succeeding label. Thus, upon termination of one batch only individual labels get lost at best because of a future wrong printing.