The invention relates to a hand-held apparatus for applying pressure sensitive labels releasably secured to a web of supporting material and including a housing having a handle, means for mounting a label roll on the housing, a delaminator mounted by the housing, an applicator for applying delaminated labels, a driver for advancing the web, means defining a feed path from the label roll to the delaminator where labels are successively peeled from the web, to the driver, and to a place of exit from the housing, means for moving the driver to advance the web including a manually engageable actuator disposed at the handle, and a leaf spring cantilivered to the housing, the web being adapted to pass into contact with the leaf spring.
In the case of a prior art apparatus of this type (US patent 4 1 16 747) excessive telescoping of the label roll proved problemsome, unless providing two disks, and for preventing mushrooming a leaf spring spaced from the disks was used.
The invention is based on the object of developing the prior art apparatus in such a manner that excessive telescoping and mushrooming are avoided in a particularly simple manner.
This problem is solved by the apparatus according to the invention, which is substantially characterized by a pair of spaced fingers cantilevered to the leaf spring for straddling the label roll to obviate excessive telescoping of the label roll.
It should be mentioned here that it is already known in connection with a labeler, without a leaf spring, of a different species (US patent 4 148 678) to associate a U-shaped wire-like flexible retainer with the frame of the housing, the two arms of said retainer straddling the label roll to prevent the roll from unwinding. In this case, the frame members must have integrally formed pairs of projections which define grooves therebetween to receive the arms in their operating position.
In the case of another hand-held labeler of a different species (US patent 4 440 123) a pair of spring arms are secured to the frame of the housing, each of said spring arms carrying a button for supporting the label roll. To the furthermost ends of said arms a pair of studs are secured, which contact one another. The sum of the lengths of said studs is approximately equivalent to the width of the label roll. In this manner, the studs help control the mushrooming of the label roll, when the outer wrap of the label roll contacts the studs.
It proved most advantageous in connection with the hand-held labeler according to the invention when the fingers cantilevered to the leaf spring are flexible and resilient. According to an embodiment that is particularly advantageous in terms of structure, the leaf spring and the fingers are of one-piece construction, most conveniently of a one-piece molded plastics construction.
For ease of manufacture of the leaf spring- fingers unit, the fingers are advantageously offset along the length of the leaf spring to facilitate molding.
Further important details, advantages and features of the invention may be seen from the following description and the accompanying drawings which are referred to explicitly in respect to all details not described in the text, wherein:
The hand-held labeler 9 illustrated in FIGURE 1 incorporates a housing 10 which includes two mating side sections 12 and 14 which are preferably molded of a plastics material. The housing 10 also includes a handle portion 16 having an actuator 17. The specific construction of the housing 10 and the components enclosed therein are described in above-mentioned U.S. patent 4,116,747 incorporated herein by reference. The labeler 9 is adapted to receive a supply of pressure sensitive labels L which are carried by a web W and wound into a roll R inserted between the opposing freely rotatable mounting members or hub members 19. A molded plastic leaf spring 21 guides the web W and labels L which it carries into the labeler 9, and the web W is directed upwardly across the inner surface of a flat platen 23 where the labels L are successively printed. Each pressure sensitive label L is printed on the platen 23 by movement of the print head 25 in response to retraction of the actuator 17, and the web W is advanced by a predetermined increment when the actuator 17 is released. The printed label L is peeled from the carrier web 10 at a delaminator 31 where the carrier web reverses and is directed downwardly and rearwardly through the labeler 9 and around a ratchet type indexing drive wheel 32 enclosed within the housing 10. As each printed label L is fed past the delaminator 31, the label is positioned to be applied to an article by a label applicator 35.
In a manner as illustrated in above-mentioned patent 4,116,747, the print head 25 is enclosed or covered by a molded plastic cover section 37 which is pivotally connected to the mating housing sections 12 and 14 by a cross shaft 38. The closure or cover section 37 is retained within its closed position by a latch mechanism which is released by pulling rearwardly on a set of outwardly projecting latch actuator knobs or pins 39, as explained in above-mentioned patent No. 4,116,747.
A replaceable ink applying roller 40 includes a porous ink retaining body or tube which is mounted on a pair of opposing hub members having corresponding outwardly projecting end journals 42. The ink roller 40 is supported and carried by a frame or holder 45 which is preferably molded of a plastics material and has a set of trunnions 47 projecting outwardly into aligned holes within the cover section 37 to form a pivot axis for the holder 45. The ink applying roller 40 and holder 45 are biased or urged toward a position where the ink roller 40 engages the printing characters on printing bands 27 and rolls across the characters in response to forward movement of the printing head 25. The biasing force is produced by a pair of spring members or elements 52 (FIGURES 1, 2) which are also molded of a plastics material such as nylon.
The leaf spring 21 has a mounting portion 60 cantilevered in opposed pockets 61. The mounting portion 60 is joined to a relatively wide portion 62 which is joined to a narrower portion 63. The deflection of the wide portion 62 is less than the deflection of the narrower portion 63. A pair of fingers 64 and 65 are connected to a marginal end portion 66 of the spring 21. The marginal end portion 66 is opposite the mounting portion 60. The spring 21 and the fingers 64 are preferably of one-piece molded plastics construction for ease of manufacture and to provide the desired functions with a minimum of parts. The fingers 64 and 65 are shown to be generally parallel to each other and to be disposed in straddling relationship with respect to the label roll R as best shown in FIGURES 2 and 3. As best shown in FIGURE 3, the fingers 64 and 65 are spaced more widely apart than the mounting members 19 which mount the label roll R. Also the finger 64 overlaps the mounting members 19 whereas the mounting member 65 does not quite overlap. The fingers 64 and 65 prevent excessive telescoping of the label roll R. Excessive telescoping is especially problemsome when the diameter of the roll R is large. As the diameter of the label roll R decreases with repeated label cycles, there is less tendency of the roll R to telescope when the label roll R is full. As shown in FIGURES 2 and 3, the spring 21 also keeps the label roll from mushrooming. Mushrooming occurs when the roll R unwinds excessively, thereby causing the outer passes of the roll R to become loose. As mushrooming occurs one of the passes of the roll R will contact the underside of the leaf spring 21 which will offer frictional resistance.
As shown in the drawings, the fingers 64 and 65 are relatively thin and are flexible and resilient so that if the labeler 10 is dropped or otherwise abused, there is not the tendency of the spring fingers 64 and 65 or the flexible resilient spring 21 to break or become bent out of shape. The fingers 64 and 65 are shown cantilevered to the spring 21 at end portion 66. The fingers 64 and 65 are shown to be offset lengthwise of the spring 21 to facilitate molding and this is a feature of the invention.
Three hook-shaped projections 67 are formed integrally with the sides of the marginal end portion 66. The projections 67 are shown to be offset lengthwise. The projections 67 are acknowledged to be prior art. The projections 67 guide the outer pass of the web as shown in FIGURES 2 and 3.
Other embodiments and modifications of this invention will suggest themselves to those skilled in the art, and all such of these are included within the scope of the invention as defined by the appended claims.