Claims:
1. In a device for the incremental advancement of a label tape, which for control of the length of the advanced increment is provided with recesses, said device including a housing, a slide guided in the housing for movement backwards and forwards in the longitudinal direction of the tape along a path of movement lying between two abutments spaced apart longitudinally to define the length of the increment to be advanced, a gripping latch biased by a spring toward a gripping position and having a gripping edge such that upon forward movement of the slide the gripping edge presses against the label tape and entrains it and upon backward movement of the slide the gripping edge is raised from the label tape, and feeling means attached to the gripping latch for sensing the recesses in the label tape and for dropping into the recesses to enable movement of the gripping latch into the gripping position, the improvement comprising at least one feeler on the gripping edge a plurality of pointed gripping teeth located on the gripping edge for movement with the gripping edge to engage the label tape, and a flat stationary guide plate juxtaposed with the slide and having several longitudinally extending grooves which correspond with the feeler and the gripping teeth and receive the feeler and the gripping teeth when the gripping latch is in the gripping
2. A device in accordance with claim 1 wherein a locking latch is located outside the path of movement of the gripping latch and is provided with pointed holding teeth, said locking latch being mounted for pivotal movement between a locking position and an open position, and a spring normally biasing the locking latch in the locking position and enabling the locking latch to move to the open position during advancement of the
3. A device in accordance with claim 2 wherein the holding teeth of the locking latch correspond with the grooves of the guide plate and fit into
4. A device in accordance with claim 3 including an abutment located such
5. A device in accordance with claim 1 wherein the gripping teeth of the
6. A device in accordance with claim 5 wherein the pyramid-like gripping teeth each include a side facing in the direction of advancement and oriented approximately perpendicular to the guide plate and the label
7. A device in accordance with claim 2 wherein the holding teeth of the locking latch have surfaces which face in the direction of advancement and which are perpendicular to the label tape and the guide plate when the
8. A device in accordance with claim 1 wherein two feelers are located on the gripping latch, one at each side of the gripping edge, said feelers being adapted to drop into marginal recesses in the label tape and
9. A device in accordance with claim 8 wherein the guide plate is mounted on the housing in which the slide is guided for pivotal movement about an axis extending parallel to the longitudinal direction of movement of the
10. A device in accordance with claim 9 including bridge-pieces on the
11. A device in accordance with claim 10 wherein the inner edges of the
12. A device in accordance with claim 11 including at least one tape guiding lug on the slide and extending in the direction of advancement, said lug being spaced at a small distance above the guide plate and extending through windows in the gripping latch and in the locking latch.
13. A device in accordance with claim 12 wherein the length, extending from the starting position of the device beyond the locking latch of the tape guiding lug corresponds approximately to the respective length of the increment of tape to be advanced.
Description:
The present invention relates to a device for the incremental advancement of labels adhered to a carrying tape in label dispensing arrangements.
Currently, there is available a device for the incremental advancement of a label tape, which for control of the length of the advanced increment is provided with recesses, the device having a slide which can be reciprocated backwards and forwards in the longitudinal direction of the tape movement between two abutments. A gripping latch having a gripping edge is biased toward a gripping position by a spring so that the gripping edge of the gripping latch presses against the label tape and entrains the tape upon forward movement of the slide, and upon backward movement of the slide, the gripping latch is raised from the tape. A feeler is carried by the gripping latch to sense the recesses in the label tape and upon dropping into a recess enables the movement of the gripping latch into the gripping position.
In such a construction, the gripping latch cooperates with a counter-face of a carriage, which is reciprocated along with the slide. The label tape to be advanced is gripped, when the feeler drops into a recess of the label tape, between the gripping edge of the gripping latch and the counter-face of the carriage and is thus entrained in the direction of advancement. In order to enable the feeler to drop into the recesses of the label tape the feeler is constructed as a finger-like part, whose feeling tip make engagement in front of the counter-face and in front of the gripping edge on the label tape to be sensed.
The above-described device has a disadvantage in that a carriage which can be moved together with the slide must be arranged under the label tape. Furthermore, there is a disadvantage in that the label tape can only be introduced with difficulty between the slide with the gripping latch and the counter-face of the carriage. A further disadvantage is that where the gripping latch makes a shallow angle with a label tape of smooth material, the tape is not engaged for advancement. Where the gripping latch makes a steep angle, the gripping latch easily becomes jammed.
It is therefore an object of the invention to avoid the disadvantages of the above-described label transport device and to provide a device which, with a simple construction and little mechanical complication, makes possible the reliable and precise incremental advancement of a label tape or of a support tape for self-adhesive label chains.
The above object is achieved by providing the gripping edge with at least one feeler and several pointed gripping teeth. A flat stationary guide plate is juxtaposed with the gripping latch and is provided with several longitudinal grooves which correspond with the feeler and the gripping teeth and receive the latter when the gripping latch is in the gripping position.
In order to ensure that upon advancing the slide and the gripping latch into the gripping position the label support tape is not entrained, it is possible to provide an arrangement wherein outside the movement range of the gripping latch a locking latch, which is provided with pointed holding teeth and opens in the transport direction of the label tape, is pivotally mounted and is held by a spring in the locking position.
Preferably, the holding teeth of the locking latch correspond with the grooves of the guide plate and fit into these grooves in the locking position.
In order to ensure that the locking latch cannot become jammed, it is possible to provide that the pivoting range of the locking latch is limited by an abutment against which the locking latch abuts in the locking position.
The gripping teeth are preferably pointed and take the form of pyramids with the side of the gripping teeth turned in the transport direction and approximately perpendicular to the guide plate. This ensures that when the feeler drops into an opening the gripping reeth immediately engage the label support tape and advance the tape.
Furthermore the holding teeth of the bcking latch can be constructed like the gripping teeth.
An advantageous form of the invention is characterised by two feelers arranged on both sides of the gripping edge and adapted to drop into marginal recesses of the label tape, and corresponding grooves in the guide plate.
In order for the label support tape to be easily threaded into the device, the guide plate can be hinged upwards about an axis running parallel to the longitudinal direction of the label tape and fixed on the housing in which the slide is guided.
For guiding the label support tape use is made of two bridge pieces arranged on the guide plate, between bridge pieces tape can be inserted.
In order to ensure that upon advancing the tape engaged by the gripping teeth, the tape section lying between the gripping latch and the locking latch cannot bulge out, a guiding lug is attached. The guiding lug is attached only a short distance from the guide plate and prevents a bulging out of the above-mentioned tape section.
The device constructed in accordance with the invention makes possible a self-regulating, precise incremental advancement of a label tape so that each label arrives in an accurately registered printing position or dispensing position.
In the following description two embodiments of the invention will be described in detail with reference to the drawings, wherein
FIG. 1 is a side view of a tape transport device constructed in accordance with the invention;
FIG. 2 is a view on the section line II--II of FIG. 1;
FIG. 3 is a view on the section line III--III of FIG. 1;
FIG. 4 is a view on the section line IV--IV of FIG. 1;
FIG. 5 is a view corresponding to FIG. 4 of a modified embodiment of the invention;
FIG. 6 is a plan view of a label tape which is incrementally advanced by the device of FIG. 5; and
FIG. 7 is a longitudinal section through an apparatus for printing, dispensing and applying of gummed labels, which is provided with the feed mechanism shown in FIG. 1.
The new device for the incremental advancement of a label tape or a label support tape 1 (both types of tape will be referred to as a "label tape") includes a slide 3, which can be reciprocated backwards and forwards in the housing 2, and which is guided in guiding slots 4 of the housing 2. Slide 3 has a gripping latch 6 mounted for pivotal movement about a pin 5. The latch 6 is biased by a spring 7 toward a gripping position wherein the lower edge or the gripping edge 8 thereof bears against the label tape 1 lying on a guide plate 12. The gripping edge 8 of the gripping latch 6 carries feelers 10 which sense marginal recesses 11 of the label tape 1. Furthermore, the gripping edge 8 has claw-like gripping teeth 9 which upon the dropping of the feelers 10 into the recesses 11 of the label tape 1 extend through the label tape 1 and thus engage the label tape. In the guide plate 12 there are grooves 13 extending in the direction of advancement of the tape, which correspond with the gripping teeth 9. Furthermore deeper grooves 14 are provided, into which the feelers 10 extend when they drop into the recesses 11 of the label tape 1.
A locking latch 20, which is mounted upon the stationary pin 23, and which is biased by an U-shaped spring 21 to a position wherein the holding teeth 22 are against the label band 1, prevents displacement of the label tape 1 in a direction opposite to the direction of advancement. In the locking position the locking latch 20 lies against an abutment 24.
The new device operates as follows:
After raising the guide plate 12, which can be pivoted about the pivot pin 28 on the housing 2, the label tape 1, shown in broken lines in FIG. 2, is inserted between two guide bridge pieces 28 located on the guide plate 12. In order to facilitate the insertion of the label tape 1, the inner edges 30 of the bridge pieces 29 are chamfered. After closing the guide plate 12 and securing the fastener 31, which is located on the housing wall 2 opposite to the pivot pin 28, the transport device is ready to operate.
Upon pivotal movement of a hand lever 15 away from the rest position thereof about pivot pin 16, by means of parts not shown device 17 is moved in the direction of the arrow, that is, to the left, as viewed in FIG. 1. The movement device 17 is coupled with a lug 19, which is attached to the slide 3 so that the gripping latch is moved freely to the left. If the hand lever 15 is released, the movement device 17 and thus the slide 3 are moved to the right owing to the biasing of a spring (not shown) coupled with the lever 15 and biasing the lever toward the rest position, and the rounded feelers 10 slide on the label tape 1 until they drop into the marginal recesses 11. When the feelers drop into the recesses 11 of the label tape 1 the gripping teeth 9 hook into the label tape 1 and entrain it in the direction of movement of the slide 3. Owing to this the tape section located between the gripping latch 6 and the locking latch 20 of the label tape 1 is held flat by a tape guide lug 32 attached to the slide 3 so that the locking latch 20 is pushed by this tape section. If the slide 3 with the gripping latch 6 is moved into the gripping position, the holding teeth 22 of the gripping latch 20 hook into the tape 1 with the labels, and the gripping latch 6 is raised with its feelers 10 thereby raising the gripping teeth 9 out of the label tape 1.
The gripping latch 6 is provided with an abutment 18, which lies against the slide 3, when the gripping latch 6 is in the gripping position. This ensures that the feeler 10 or other parts of the gripping latch touch the guide plate 12.
The guide lug 32 extends through windows 33, which are located in the gripping latch 6 and in the locking latch 20. Both the gripping teeth 9 and the holding teeth 22 are provided with surfaces or sides 26 and 27 facing in the direction of advancement. Sides 26 and 27 are perpendicular to the direction of advancement and substantially perpendicular to the label tape 1. This construction of the gripping and holding teeth 9 and 22 brings about a rapid and reliable engagement of the label tape 1.
The device illustrated in FIG. 5 differs from the device shown in FIGS. 1 to 4 essentially only in that the feeler 10 is located in the middle of the gripping latch 6 in order that a hole mark 11' positioned in the middle of the label tape 1' can be sensed. Furthermore, two tape guiding lugs 32' are located on the slide 3 and extend through windows 33' in the gripping latch 6 and the locking latch 20.
FIG. 7 illustrates an apparatus for printing, dispensing and applying stick 8 on labels. The apparatus is provided with a feed mechanism shown in FIG. 1. This known apparatus is provided with a handle 35, an actuating lever 15, a printing mechanism 36, a deflecting bar 37 for the label support tape, an applicator for the labels and a supply roll of label-strip.