Abstract:
An apparatus and method for dispensing individual sheets of stack of adhesive coated sheets is disclosed. The apparatus is comprised of a carriage for receiving the stack of adhesive coated sheets; reciprocating means for intermittently driving the carriage from a first rest position to a second rest position and vice versa; and guiding means for directing the distal edge of a sheet from a guide input to a guide output as the carriage is driven by the reciprocating means from the first rest position to the second rest position or vice versa. The invention is useful for dispensing said sheets without requiring that each sheet be pulled through or drawn out the guide output under the force of the releasable adhesive bond between adjacent sheets. Using the invention, one may cause a sheet to be dispensed to a position where it is accessible to the user only when the sheet is actually needed.

Description:
BACKGROUND 
     This present invention relates to a device for dispensing thin sheets including paper. More particularly, the invention relates to a method and apparatus for dispensing individual sheets of adhesive coated products, including note pad papers, from a stack where the sheets releasably adhere to one another along opposite edges of successive sheets. 
     The prior art includes a number of dispensers for use with sheet and various other stationary products. The vast majority of the devices are designed to receive a uniform stack of identical sheets. The individual sheets are then dispensed by engaging and moving the sheet to a position that is accessible to the user. The means for engaging the sheet is typically a mechanical arm that frictionally engages the sheet and slidably removing it from the remaining sheets of the stack. This same operational mechanism is repeated in a number of patents, namely U.S. Pat. No. 4,071,165 to Leopoldi, U.S. Pat. No. 4,941,591 to Lin et al, U.S. Pat. No. 4,865,223 to Huang, U.S. Pat. No. 5,104,000 to Goff, and U.S. Pat. No. 3,517,855 to Hillis. However, each of these devices is impractical for use with the unbound, adhesive coated sheet products to which the present invention pertains. 
     U.S. Pat. No. 5,765,721 to Vance discloses a mechanism for dispensing individual sheets of note pad paper having a reusable adhesive strip on each leaf of the note pad. Although the invention is effective for separating an individual sheet from a stack of adhesive coated sheets, it is limited to a specific type of note paper in which the adhesive is applied to a common edge or side of every sheet within the stack. As such, it is inoperable with respect to the type of sheet product the present invention is directed toward. 
     U.S. Pat. No. 5,080,254 to Feer, U.S. Pat. No. 6,267,263 to Emoff et al., U.S. Pat. No. 4,907,825 to Miles, and U.S. Pat. No. 5,299,712 to Carlson et al. are intended for use with note pad papers that releasably adhere to one another using a thin adhesive strip along opposite edges of successive sheets. An example of an adhesive coated stack is sold under the trade designation “POST-IT” by Minnesota Mining and Manufacturing Company, St. Paul, Minn. 
     The patents to Feer, Emoff, Miles, and Carlson each disclose an apparatus in which the upper most sheet of the stack of adhesive coated sheets is made to protrude from a slot in the top surface of each container. The edge of the uppermost sheet opposite the adhesive strip is drawn from the container as a consequence of the removal of the previous uppermost sheet. Once an edge is ejected from the slot, the sheet remains in the position that is visible and accessible to the user until it is removed. In each prior art dispenser, the edge of the uppermost sheet must necessarily protrude from the dispenser to permit the user to access the sheet as well as manually draw the next sheet below into the position of the upper most sheet. 
     SUMMARY 
     The present invention overcomes the limitations of the prior art with a dispenser that supports the uppermost sheet in proximity to the dispenser&#39;s output until the dispenser is actuated, at which point the uppermost sheet is ejected from the dispenser using a mechanism that is independent of the process or means for removing the previous uppermost sheet, as required by the prior art. 
     In one embodiment of the present invention, the apparatus for dispensing individual sheets from a stack of adhesive coated sheets is comprised of a guide output; guiding means for directing the distal edge of the uppermost sheet out of the guide output; and repositioning means for intermittently altering the relative position of the stack and guiding means. In this embodiment, the distal edge of the uppermost sheet is driven from the position within the guiding means to a position accessible to the user at the guide output when the relative reposition of the stack and guiding means are changed by the repositioning means. The guiding means may take any of a number of forms including a pair of substantially planar structures that converge in the direction of the dispenser&#39;s guide output. The repositioning means may include, for example, an electro-mechanical or other power operated device for altering the relative positions of the stack and guiding means. One skilled in the art will recognize that repositioning means may operate by moving the stack relative to the guiding means or, in the alternative, by moving the guide means relative to the stack. 
     In another embodiment, the dispenser is comprised of a carriage for retaining the stack of adhesive coated sheets; guiding means for laterally supporting the distal edge of a sheet and for directing the distal edge of the sheet out of the guiding means; and reciprocating means for intermittently altering the relative position of the carriage and guiding means. The distal edge of the sheet being laterally supported by the guiding means is directed out of the guiding means as the relative position of the carriage and guiding means are altered by the reciprocating means. The reciprocating means may actuate the carriage, the guide means, or both in response to the user input. 
     In another embodiment of the invention, the dispenser is comprised of a carriage in which the stack of adhesive coated sheets sits; reciprocating means for intermittently driving the carriage from a first rest position to a second rest position and vice versa; and guiding means having a guide input and guide output for directing the distal edge of a sheet from the guide input to the guide output as the carriage is driven by the reciprocating means from the first rest position to the second rest position or vice versa. 
     The method of dispensing sheets from a stack of adhesive coated sheets located at a first rest position, is comprised of the steps of positioning the distal end of an uppermost sheet against a first guide of a guiding means; repositioning the stack of adhesive coated sheets to a second rest position such that the distal end of an uppermost sheet is dispensed from the a guide output of the guiding means where it is accessible to the dispenser&#39;s user; positioning the distal end of the next most sheet, i.e. the sheet immediately below the uppermost sheet, against a second guide of the guiding means; and repositioning the stack of adhesive coated sheets to the first rest position such that the distal end of an next most sheet is dispensed or ejected from the guide output where it is accessible to the dispenser&#39;s user. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view illustrating the exterior of the top, front and side of the preferred embodiment of the present invention. 
     FIG. 2 is a perspective view of the internal side of the base structure illustrating in part the carriage and housing according to the preferred embodiment. 
     FIG. 3 a  is a plan view of the internal side of the lid structure of the preferred embodiment. 
     FIG. 3 b  is a plan view of the internal side of the top of the base of the preferred embodiment. 
     FIG. 4 a  is a plan view of the internal side of the bottom of the base of the preferred embodiment with the carriage in the first rest position. 
     FIG. 4 b  is a plan view of the internal side of the bottom of the base of the preferred embodiment with the carriage in the second rest position. 
     FIG. 5 is a longitudinal cross section through the preferred embodiment of the dispenser with the carriage in the first rest position. 
     FIG. 6 is a longitudinal cross section through the preferred embodiment of the dispenser with the carriage in the second rest position. 
     FIG. 7 a longitudinal cross section through the preferred embodiment of the dispenser with the uppermost sheet being removed from carriage. 
    
    
     DETAILED DESCRIPTION 
     The invention pertains to a dispenser for dispensing individual sheets of a variety of materials from a stack of adhesive coated sheets. The preferred form of stack includes a plurality of substantially rectangular paper sheets of paper, for example, that have a strip of adhesive that releasably attaches an uppermost sheet to the adjacent lower sheet in the stack. The strip of adhesive is applied on the underside of a given sheet along one side or edge, this edge being referred to as the proximal edge. The distal edge, then opposite the proximal edge, does not include any adhesive although it may be releasably attached to a strip of adhesive applied to the sheet immediately above. Thus, the distal edge of any given upper sheet will correspond to the proximal edge of the adjacent lower sheet. 
     Adhesive coated sheets as described above may be assembled to form a stack of adhesive coated sheets where the sheets releasably adhere to one another along opposite edges of successive sheets. This stack of adhesive coated sheets is such that the adhesive edge alternates between opposing sides from sheet to sheet in a style that resemble an accordion when drawn apart from one another. As will be seen below, the reciprocating mechanism of the present invention is ideally suited for dispensing a single sheet from such a stack of adhesive coated sheets. With appropriate modification, the dispenser can be designed to dispense papers of various sizes, including 3 inch square and 3 by 5 inch, 2⅝ by 2⅞ inch, 1½ by 2 inch, 3 by 4 inch, 3 by 3{fraction (5/16)} inch, 1 by 3 inch, 2 by 3 inch 1 by 1¾ inch, or sheets of different adhesive configurations, including that described in U.S. Pat. No. 5,390,819 to Kaye, herein incorporated by reference. 
     Referring to FIG. 1, a perspective view of the exterior of the preferred embodiment is illustrated looking on from the top, front and side. The dispenser  100  is preferably comprised of a lid  101  and a base  102  that frictionally engage one another. The lid structure  101  of the preferred embodiment includes a push bar  103 , which causes a single sheet to be dispensed from the slot or guide output  104 . 
     Referring to FIG. 2, a perspective view of the internal side of the base  102  illustrating the carriage and housing according to the preferred embodiment. The exterior of the internal housing  212  is comprised of one or more push button switches  211  that are engaged when the push bar  103  is depressed. The interior of the housing  212  of the preferred embodiment includes various electrical components including the reciprocating means discussed below and one or more batteries for use with portable or desk-top dispenser units. 
     The carriage  205  receives a stack of adhesive coated sheets (not shown) which is held in position by the carriage walls  207 . The carriage  205  of the preferred embodiment includes a plurality of wheels (not shown) that are supported from underneath by the support  209 . One skilled in the art will recognize a number of alternative configurations, including rails, rollers and bearing, suitable for permitting relative movement of the carriage with respect to the cooperating structures including the guiding means discussed below. The carriage  205  is driven by the reciprocating means mounted in part within the housing  212 , preferably. The movement of the carriage  205  is confined to oscillate within a region defined by the flange  210  and the housing  212  in the preferred embodiment. 
     In the preferred embodiment, the reciprocating means drives the carriage  205  and the stack therein between two rest positions corresponding to the maximum displacement of the carriage  205  through its oscillatory cycle. The carriage  205  illustrated in FIG. 2 is shown at a first rest position corresponding to the maximum throw of the reciprocating means. The carriage  205  sits idle in this first rest position until a user causes the reciprocating means to drive, i.e. to reposition, the carriage  205  to a second rest position which, in the preferred embodiment, is adjacent to the housing  212 . The path traced as the carriage  205  oscillates between the first and second rest positions approximately coinciding with the perimeter defined by the flange  210  and the housing  212 . 
     Referring to FIG. 3 a , a plan view of the internal side of the lid structure of the preferred embodiment is illustrated. From this view, the push bar mechanism, guiding means and guide output  104  are visible. The push bar mechanism of the preferred embodiment is comprised of push bar  103  and the hinge assemblies  318  that pivotably attach the push bar  103  to the lid  101 . The posts  319  are positioned and sized to engage the push button switches  211  when the push bar  103  is depressed. The spring  320 , which is affixed to the lid  101  by means of rivet  321 , returns the push bar  103  to its initial position flush with the exterior of the lid  101  after it is depressed and released. The distal end  322  of the push bar  103  includes a lip that engages the lid  101  to prevent the push bar  103  from pivoting beyond its undepressed position flush with the lid  101 . The plan view of the top of the base  102  shown in FIG. 3 b  is included to illustrate the alignment of the carriage  205  with the guide output  104  as well as the push bar  103  and the button switches  211 . 
     The guiding means in the preferred embodiment is comprised of a forward guide  316  and a rear guide  317  that cooperate with the carriage  205  to hold and channel individual sheets to and out of the guide output  104 . In this embodiment, the guides  316  and  317  are substantially planar structures that converge to create a tapered opening that is widest at the guide input. The static and kinetic coefficients of the material from which the guiding means is constructed should be relatively low to facilitate the sliding of the individual sheet to the guide output  104 . One skilled in the art will recognize that the tapered relationship between the guides  316  and  317  is not strictly necessary and is but one of many means for laterally supporting and directing an uppermost sheet in its upward migration to the guide output  104  as the carriage  205  is driven between the two rest positions. The guides  316  and  317  are supported by means of the mounting plate  315  and screws (not shown) that engage the lid  101 , for example. 
     Referring to FIG. 4 a , a plan view of the internal side of the bottom of the base of the preferred embodiment is illustrated with the carriage in the first rest position. In this view, the reciprocating means, the flange  210  as well as the underside of the support  209  and internal housing  212  are visible. The support  209  includes the access  424  through which the reciprocating means engages the carriage bottom  206  and repositions the carriage  205 . The housing  212  in this embodiment houses the battery  439  and portions of the reciprocating means. 
     The function of the reciprocating means is to drive, or otherwise reposition, the carriage  205  between the first and second rest positions in response to a user prompting. The effect of repositioning the carriage  205  is to force an individual sheet from the stack up the guiding means and through the guide output  104 . In preferred embodiment, the reciprocating means is comprised.of an electric motor  425 , belt  426 , gears  427  through  429 , drive rod  434 , swing arm  436 , interrupt switch  432  and corresponding electrical circuitry for intermittently powering the motor  425 . 
     Equivalent means for reciprocating the stack of adhesive coated sheets may include manual, electro-mechanical, pneumatic, or hydraulic devices for providing the force to reposition the stack with respect to the guiding means. 
     The user initiates the dispensation of a sheet by causing the push button  211  to be depressed, which in turn engages the motor  425  and actuates the carriage  205 . The turning of the motor  425 , coupled to the first gear  427  by means of the belt  426 , causes rotation of the series of step-down gears including the first gear  427 , second gear  428  and third gear  429 . The third gear  429  rotates until either the first or second cam  430  or  431  engages the interrupt switch  432 . When depressed, the interrupt switch  432  severs electrical communication between the motor  425  and the battery  439 , causing the motor  425  to stop. 
     As the third gear  429  rotates, the carriage pin  438  is made to reciprocate to and fro within the access  424 . More specifically, the drive rod  434  is pivotally engaged to the third gear  429  and is linearly displaced in response to its rotation. The drive rod  434  is pivotally engaged to the swing arm  436  which is, in turn, anchored to the support  209  by means of anchor pin  437 . On the opposite end of the swing arm  436  is the pin  438 , which is anchor to the carriage bottom  206  and slidably engaged to the slot  440  of the swing arm  436 . 
     Referring to FIG. 4 b , a plan view of the internal side of the bottom of the base of the preferred embodiment is illustrated with the carriage in the second rest position. The location of the interrupt switch  432  and the first and second cams  430  and  431  are positioned on the third gear  429  such that gear  429  rotates approximately  180  degrees with each activation of the push bar  103 . Further, the angular position of the pivot  433  on the third gear  429  is such that the pivot  438  stops at one of the two ends of the access  424 . In this embodiment, the leftmost point of the pivot  438  corresponds to the first rest positions of the carriage  205  while the rightmost point of the pivot  438  corresponds to the second rest positions of the carriage  205 . The throw of the reciprocating means is defined by the radial position of the pivot  433 , with respect to the center of the third gear  429 . In the preferred embodiment, the throw is equal to half the distance between the carriage&#39;s first and second rest positions. 
     Referring to FIG. 5, a longitudinal cross section through the preferred embodiment of the dispenser with the carriage in the first rest position is illustrated. The carriage  205  includes a stack of adhesive coated sheets  541  and an uppermost sheet  542  which is laterally supported by the forward guide  316 . In this embodiment, the uppermost sheet  542  does not protrude beyond the guide output  104  until after the push bar  103  is engaged and the carriage  104  is made to reciprocate. The position of the uppermost sheet  542  against a guide  316  (or against  317  when the carriage  205  is in the second rest position) as illustrated depicts the relative position of the uppermost sheet  542  with respect to the guiding means (1) after the stack has been loaded and (2) after the carriage  205  is reciprocated to the first rest position and the prior uppermost sheet removed. 
     Referring to FIG. 6, a longitudinal cross section through the preferred embodiment of the dispenser with the carriage in the second rest position is illustrated. Here, the carriage  205  has advanced to the second rest position in response to the depression of the push bar  103 . The movement of the carriage  205  causes the distal end of the upper most sheet  542  to be driven up to and out of the guide output  104  where it is accessible to the user. 
     Referring to FIG. 7, a longitudinal cross section through the preferred embodiment of the dispenser with the uppermost sheet being removed from carriage is illustrated. When the uppermost sheet  542  is removed, the underlying adhesive strip at the proximal end of sheet  542  causes the distal end of the next sheet  543  below to be drawn up into the guide input. Before the next sheet  543  is drawn from the guide output, the adhesive bond between sheets  542  and  543  gives way and the next sheet  543  below remains releasably attached to the stack  541  where it is laterally supported by the rear guide  317 . As before, the next most sheet  543  ascends to the position of the uppermost sheet and does not protrude beyond the guide output  104  until after the push bar  103  is engaged and the carriage  104  is made to reciprocate back to the first rest position. 
     The relative positioning between the guiding means and the stack  541 , preferably located in the carriage  205 , is important to the operation of the present invention. According to this embodiment specifically, the distance between the guiding means and the stack  541  positioned in the carriage  205  is sufficiently large that the distal end of the uppermost sheet  542  is below or substantially flush with the guide output  104  in one rest position, while the distance must be sufficiently short that the distal end of the uppermost sheet  542  may ascend above the guide output  104  when the carriage  205  is drive to the opposite rest position. 
     In the case of the 3 inch square adhesive coated paper dispenser of the preferred embodiment, the guiding means is centrally position between the between the first and second rest position about which the carriage  205  oscillates. The lateral displacement of the carriage  205  as it reciprocates between the first and second rest positions is approximately 2 inches. The distance between the guide output  104  and the bottom of the carriage  205  is approximately 2 inches. The distance between the guide input and guide output  104  is approximately 1.4 inches. The angle of the angle the forward and rear guide  316  and  317  with respect to the horizontal is approximately arccos (0.6/3.5). One skilled in the art will recognize that these parameters are subject to variation without frustrating the functionality of the invention. 
     One skilled in the art will recognize that the invention may take the form of various embodiments different than that described above. For example, the relative positions of the guiding means and stack  541  may be achieved by reciprocating the guide means relative to the stack  541 , or by moving both simultaneously. In embodiments in which the guiding means is reciprocated, reciprocating means engages the guiding means while the stack  541  remains static. 
     The method of dispensing the uppermost sheet  542  of a stack  541  from the dispenser  100  is comprised of the steps of positioning the distal end of the uppermost sheet  542  against the forward guide  316 , for example; repositioning the carriage  205  and stack  541  to the second rest position, for example, such that the distal end of the uppermost sheet  542  is dispensed from the guide output  104  where it is accessible to the dispenser&#39;s user; positioning the distal end of the next sheet, i.e. the sheet adjacent to the uppermost sheet, against the rear guide  617 , for example; and repositioning the stack  541  to the first rest position such that the distal end of an next most sheet is dispensed from the guide output  104  where it is accessible to the dispenser&#39;s user. In each of the various embodiments of this method, the step of positioning the distal end of the next sheet, as described above, is achieved by supporting the distal end of the next sheet with the guiding means in such a way as to permit the relative movement of the stack  541  to cause the sheet to be dispensed. In this manner, the underlying sheets of the stack can be ejected from the guide output without necessarily relying on the releasable adhesive bond between the uppermost sheet and next sheet below to draw sheets through the guide output  104 . 
     Although the above description contains many specifics, these should not be construed as limiting the scope of the invention, but rather as merely providing illustrations of some of the presently preferred embodiments of this invention. Therefore, the invention has been disclosed by way of example and not limitation, and reference should be made to the following claims to determine the scope of the present invention.