There are a number of situations in which it is necessary to accurately place a label in association with a substrate. This is most common for mailpieces which have address labels thereon including bar coding or other machine readable information designed to be used with postal service scanners. While commercial mechanisms exist for automatically applying labels in a substantially accurate manner to mailpieces, typically used tamp mechanisms are pneumatically powered, and there are many complex components which make such applicators expensive (e.g. greater than U.S. $20,000.00). Also, they are difficult to install, noisy, and take up more than a desirable amount of work space. For example, see U.S. Pat. No. 4,595,447. Other automatic applicators (such as shown in U.S. Pat. Nos. 4,784,714 and 4,321,103, and European published application 0577241), even if they do not require pneumatic tamp mechanisms, have a significant number of complex components and/or do not apply the labels to the mailpieces, or other substrates, with a high degree of accuracy.
According to the present invention, a label applicator, and a method of applying labels to substrates, are provided that have the necessary accuracy to apply address labels to mailpieces so that they may be effectively automatically scanned by postal equipment, yet are relatively simple and inexpensive. The applicator according to the invention is semi-automatic, is compact so that it can fit on a desktop (in fact both an associated printer and the label applicator can fit on a desktop), no pneumatic hookup is typically required, and no external power is typically required since the electricity for powering the label applicator may come directly from the printer. Also, in the preferred embodiment the mailpiece is moved into contact with the label; since the label does not move during application this gives greater accuracy in placement. The applicator is compatible with both linered and linerless labels and printers, and can be used with printers of a variety of types including thermal transfer, direct thermal, and ink jet. The applicator may be mounted with the printer, or easily detached from the printer, and the cost of the applicator is less than half of commercial automatic applicators.
According to one aspect of the present invention, a label applicator is provided comprising the following components: A label feed mechanism which feeds a label having a first face with pressure sensitive adhesive and a second face with indicia printed thereon. A label positive stop cooperating with the feed mechanism to stop a label fed by the feed mechanism in a first desired position. A holding device which holds the label in the first desired position. A substrate positive stop which stops a substrate at a second desired position in alignment with a label at the first desired position. And automatic means for moving a substrate at the second desired position into, and then out of, contact with the pressure sensitive adhesive of a label at the first desired position so that the label sticks to the substrate, and is removed from the holding device with the substrate.
The automatic means for moving the substrate may comprise a wide variety of structures. For example, it may comprise a traveling nut on a screw which is powered by an electric or pneumatic motor, a pneumatic cylinder, or a variety of other conventional primarily linear actuators. In the preferred embodiment, however, the automatic means comprises a linear solenoid and a tamp pad connected thereto. Preferably, the substrate positive stop is vertically below the label positive stop, and the linear solenoid is positioned so as to move the tamp pad, and a substrate (such as a mailpiece) thereon, at least primarily upwardly to bring the substrate into contact with the label adhesive. The label positive stop is vertically movable upon contact with the tamp pad; for example the label positive stop may comprise one or more pins which fit through openings in a surface against which the label is held, with a head preventing the pins from falling through the openings, but the pins unconnected to the surface so that they may reciprocate up and down. A number of different holes may be provided so that the position of the label stop is adjustable.
Preferably, the label feed mechanism, the label positive stop, holding device, substrate positive stop, and solenoid are mounted within a housing dimensioned to fit on a desktop. The holding device may comprise a support having first and second faces with one or more apertures therein extending between the faces, the first face for engaging a label; and one or more electric fans adjacent the second face and positioned to pull air through the one or more apertures, suction created by the one or more fans holding a label to the first face. The label feed mechanism may comprise at least one set of rollers (e.g. one set within the label applicator, and possibly--especially where linerless labels are used--another set in the printer).
The automatic means for moving the substrate preferably are controlled by a control device having at least two position sensors for sensing the position of a label and a substrate, respectively. There may be further provided a printer for printing indicia on the label second face, the printer also dimensioned to fit on a desktop, and a mounting plate connecting the printer and housing together at a bottom portion of each, the mounting plate having feet extending downwardly therefrom. Where the applicator is for use with a substrate, there preferably is further provided a mailpiece support extending outwardly from the housing opposite the feed mechanism, the support plate facilitating manual movement of a mailpiece into the housing to contact the positive stop. A solenoid, sensors (e.g. optical sensors), feed mechanism, and holding device are preferably electrically powered, electric power being provided by connection to the printer.
According to another aspect of the present invention a method of applying address labels to a mailpiece in a semi-automatic manner using a label applicator including label and mailpiece positive stops and housing, each label having a first face with pressure sensitive adhesive, and a second face with address indicia thereon, is provided. The method comprises the steps of: (a) Feeding a label into the housing until positively stopped at a first desired position so that the first face thereof is substantially uncovered. (b) Releasably holding the label in the first position. (c) Feeding a mailpiece into the housing until positively stopped at a second desired position aligned with the first position. (d) Sensing the label and mailpiece contemporaneously at the first and second positions, respectively. (e) In response to step (d) automatically effecting relative movement of the label and mailpiece with respect to each other so that the adhesive of the label sticks to the mailpiece. And (f) removing the mailpiece from the housing, with the label applied, the label being automatically released from being held in the first position.
Steps (c) and (f) are preferably practiced manually, and step (e) is practiced by moving the mailpiece while the label remains substantially stationary. There may also be the further step of adjusting the positive stops for both the label and the mailpiece to accommodate labels and mailpieces of different sizes or configurations. Step (d) may be practiced optically, utilizing two different sensors, one for the mailpiece and the other for the label. There is also preferably the further step of printing the label second face (e.g. by thermal transfer, direct thermal, or ink jet techniques) substantially immediately (typically, during normal operation, only about 5-20 seconds) before the label is applied to the mailpiece.
According to another aspect of the present invention a desktop mounted label printer and applicator assembly is provided. The assembly preferably comprises the following components: A printer comprising a housing, a print head within the housing, and a source of electric power. A label applicator disposed in a housing. A feed mechanism which feeds printed labels from the printer housing into the label applicator housing, the feed mechanism being electrically powered. The housings are dimensioned and configured to collectively fit on a desktop. An electrically powered label holding device disposed in the label applicator housing. An electrically powered device which effects relative movement between a substrate (e.g. mailpiece) and the label so that pressure sensitive adhesive on one face of the label moves into contact with, and adheres to, the substrate, disposed within the label applicator housing. Electrically powered sensors for sensing the relative positions of the label and substrate, the sensors disposed in the label applicator housing. And the electrically powered holding device, moving device, and sensors, connected up to the source of electrical power of the printer. The details of the mechanisms utilized herein are preferably as described above, although under some circumstances other mechanisms may be utilized (such as a pneumatically operated moving device for moving the label with respect to the substrate, etc.).
It is the primary object of the present invention to provide a simple yet effective label applicator, combination label printer and applicator assembly, and method of applying labels to mailpieces or other substrates, which are simple, inexpensive, yet highly accurate in placement of labels on substrates. This and other objects of the invention will become clear from a detailed description of the invention and from the appended claims.