Label printer for linerless labels

Abstract

A linerless label is printed and separated from a ribbon (7) of the labels by a label printer (1, 1) having a printing unit (2, 2), a holder (6) for the linerless label ribbon, a cutting unit (3) and a paper-feeding unit (8, 8). The paper-feeding unit advances the linerless label ribbon through the printing unit and the cutting unit. The printing unit prints a part of the linerless label ribbon as it is advanced. The printed linerless label (9) is separated from the linerless label ribbon by the closing of at least two blades (4, 5) arranged on the sides of the linerless label ribbon. Afterward, the blades return to an open starting position for a next cutting operation. Before the blades open, the linerless label ribbon is pulled back from the blades, creating a distance (z) between the linerless label ribbon and the blades).

Claims

1. A method for printing a linerless label and separating the printed label from a ribbon of the linerless labels, comprising the steps of: obtaining a printing unit, comprising: a label printer; a holder, adapted for holding the ribbon of linerless labels; a cutting unit, having at least two blades with at least one of the blades arranged on each sides of the ribbon of linerless labels; and a paper-feeding unit; advancing the ribbon of linerless labels through the printing unit and the cutting unit, using only the paper-feeding unit; printing on a part of the ribbon of linerless labels during the advancement thereof, using only the printing unit, generating a printed linerless label; separating the printed linerless label from the ribbon of linerless labels, by closing the blades together; retracting the ribbon of linerless labels away from the closed blades, using only the paper-feeding unit, generating a gap between the ribbon of linerless labels and the closed blades; and returning the blades to an open condition.

2. The method of claim 1 wherein the blades begin returning to the open position as soon as the ribbon of linerless labels is no longer in contact with the blades.

3. The method of claim 1 wherein the printing unit further comprises a print head, and the gap between the ribbon of linerless labels and the blades is the same as the distance between the print head and the blades.

4. The method of claim 1 wherein the step of separating the printed linerless label is achieved by closing the blades together across the entire width of the ribbon of linerless labels.

5. The method of claim 1 wherein the label printer further comprises a receiving element having a sensor; so that the printed linerless label falls onto the receiving element after being separated from the ribbon of linerless labels and, in response to a signal of the sensor, a next-following linerless label is released for delivery if no linerless label is present on the receiving element (10).

6. The method of claim 5 wherein one of the two blades is statically fixed to the label printer and the other blade is movable.

7. The method of claim 6 wherein the statically fixed blade is positioned such that while the blades are closed, the statically fixed blade is spatially between the movable blade and the receiving element.

8. The method of claim 1 wherein one of the two blades is statically fixed to the label printer and the other blade is movable.

9. The method of claim 8 wherein the movable blade is positioned such that while the blades are closed, the movable blade is positioned on the opposite side of the statically fixed blade where the printed label output is located.

10. A computer-assisted program for the implementation of the method of claim 1 wherein a signal is generated to trigger a pulling-back movement of a linerless label ribbon.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The inventive method and its implementation in a label printer are explained in detail with the help of the following drawing figures, wherein elements that are identical from one figure to another carry the same reference symbols, and wherein:

(2) FIG. 1 shows a label printer in the process of printing and advancing the linerless label ribbon;

(3) FIG. 2 shows a label printer in the process of separating the linerless label from the linerless label ribbon;

(4) FIG. 3 shows a label printer in the process of pulling back the linerless label ribbon from the blades of the cutting unit;

(5) FIG. 4 shows the label printer with the blades of the cutting unit in the process of moving away from each other;

(6) FIG. 5 represents a flowchart with the steps of the method of printing and separating linerless labels for a label printer; and

(7) FIG. 6 shows an embodiment of a label printer wherein the paper-feeding unit has two rollers with respectively opposite sense of rotation, in the process step of pulling back the linerless label ribbon from the blades of the cutting unit.

DETAILED DESCRIPTION OF THE DISCLOSED EMBODIMENTS

(8) FIGS. 1 to 4 show a label printer performing the steps of the method of printing and separating linerless labels. The label printer is represented only schematically, as the specific design configuration is of no relevance. The illustrated label printer 1 includes a printing unit 2, a cutting unit 3 with at least two blades 4 and 5, a holder 6 for a roll of the linerless label ribbon 7, and a paper-feeding unit 8. The label printer 1 can additionally include a receiving element 10 with a sensor 11. The printing unit is arranged above the paper-feeding unit 8, wherein the paper-feeding unit 8 is in this case simultaneously combined with the print roller. The paper-feeding unit can also include more rollers than are shown in FIG. 1. The black square within the printing unit 2 represents the location of the printing process (print head).

(9) The word forward in the present context means the sense of direction of the label delivery. In FIGS. 1 to 4 this means from left to right as seen by a viewer of the drawings. Forward in each of the drawings is the direction in which the end of the linerless ribbon 7 is pointing. Since the aforementioned components are enclosed inside a housing of the label printer, the area after the blades 4 and 5 is considered as outside, and the area before the blades is considered as inside, with the cutting unit being, of course, arranged inside the housing.

(10) In FIGS. 1 to 4 and 6, the blade 5 is shown as stationary and, in the closed position of the blades 4, 5, arranged between the receiving element 10 and the movable blade 4.

(11) FIG. 1 shows a label printer 1 in the process of printing on the linerless label ribbon 7. The print head of the printing unit 2, represented by the black square, symbolically indicates the location where the printing takes place. With a steady feed movement as indicated by the circular arrow, one line after another is printed onto the linerless label ribbon 7 by means of the paper-feeding unit 8. The printed information may have been transmitted for example by a weighing scale (not shown) to the label printer 1. After the printing has been completed, the linerless label ribbon 7 is brought into the position in which the linerless label is to be separated from the linerless label ribbon 7.

(12) In FIG. 2, the linerless label 9 is being separated from the linerless label ribbon 7 at a single point across an entire width thereof by the cutting unit 3 with the two blades 4 and 5 of the cutting unit 3 moving against each other as indicated by the two arrows to the left of the blades 4 and 5. The linerless label 9 is now no longer connected to the linerless label ribbon 7 and sticks out on the outside of the label printer 1 so that it can be taken off. The linerless label ribbon 7 is now in contact with the blade 5 on the inside.

(13) In the step that distinguishes the invention, the linerless label ribbon 7 is now pulled back by a certain amount as shown in FIG. 3. This creates a distance z between the leading end of the linerless label ribbon 7 and the surface of the blade 5 that faces towards the interior of the housing. Consequently, the linerless label ribbon 7 is no longer in contact with the blade 5. To create the distance z, the paper-feeding unit 8 is operated in the reverse direction compared to printing. It has been found that even a small distance zjust enough that the linerless label ribbon 7 no longer touches the blade 5is sufficient to prevent residues of adhesive from adhering to the blade. The maximum distance z from the blade 5 is limited only by the position of the printing unit 2 in relation to the cutting unit 3, i.e. how far the linerless label ribbon can be pulled back so that a new printout can be started.

(14) In regard to the pulling back, care should be taken that the linerless label ribbon 7 does not leave its guide track. The maximum distance z has been reached when the linerless label ribbon 7 is pulled back to the print head of the printing unit 2. Expressed in numbers, the distance z is 0.5 to 5 cm.

(15) FIG. 4, finally, shows the blades 4 and 5 being moved away from each other, as indicated again by the two arrows to the left of the blades 4 and 5. The cut-off linerless label 9 can now be attached to the object that is to be labeled. A delivery of a new linerless label can now begin. As is evident from FIG. 4, the printout on the new label can start closer to the cut-off end of the not yet printed linerless label ribbon 7. Thus, the method is conducive to an economical use of label paper.

(16) If the printed linerless label 9 is not taken away by the user, it will fall onto a receiving element 10. A sensor 11 detects if a linerless label 9 is present on the receiving element 10. The signal of the sensor 11 can be used to prevent that a subsequent delivery of a linerless label begins before the last printed linerless label 9 has been removed. This arrangement prevents that two linerless labels become stuck together.

(17) The sensor 11 can be realized with different sensor types, for example with a reflective photoelectric barrier.

(18) FIG. 5 serves to visualize the method with its steps once more in a flowchart diagram. The step that distinguishes the inventive method, i.e. the pulling back, is represented by a broken line.

(19) FIG. 6 shows a label printer 1 in the process step of pulling back, wherein the paper-feeding unit 8 has two rollers with respectively opposite sense of rotation. This and other arrangements of the printing unit and the paper-feeding units can likewise be employed to carry out the method according to the invention.

(20) Of course, the method presented here is not limited to applications as label printers for weighing scales, but can also be used with other checking devices where the result of the checking process is documented on a label. It is also possible to employ the method in an automated packaging line where the step of attaching the labels to the checked objects is fully automated.