Abstract:
A paper towel dispenser includes a housing with an inner chamber configured to support a paper supply and a dispensing aperture for dispensing paper from the paper supply. The paper supply includes a side that is formed by superimposed edge portions of paper from the paper supply. An indicator mechanism is affixed to the housing within the inner chamber and is disposed adjacent the paper supply. The indicator mechanism includes an indicator operably connected to a release mechanism. The indicator is movable between a retracted position and an indicating position. The release mechanism is pivotally biased away from the housing and is releasable in response to the paper supply being reduced below a predetermined amount. Upon release of the release mechanism, the release mechanism causes the indicator to move to the indicating position.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
   This application is a division of U.S. application Ser. No. 11/066,135, filed Feb. 23, 2005, which is a division of U.S. application Ser. No. 10/359,168 filed Feb. 6, 2003, now U.S. Pat. No. 6,908,059, which is a continuation-in-part of U.S. application Ser. No. 09/713,317, filed Nov. 16, 2000, now U.S. Pat. No. 6,517,025. The priorities of the foregoing applications are hereby claimed and the entirety of their disclosures incorporated herein by reference. 

   FIELD OF THE INVENTION 
   The field of the present invention is indicators for alerting users that the paper reserve in a paper towel dispenser is low. 
   BACKGROUND OF THE INVENTION 
   It is conventional to dispense paper towels from an upright roll, that is, a roll whose center axis is oriented vertically. The center of the roll is coreless, so the paper can be pulled from the inner periphery of the roll, that is, usually downwardly through a hole formed in a floor of a dispenser housing. Therefore, the radial thickness of the roll gradually diminishes from a roll inner periphery toward a roll outer periphery. Eventually, only a very small radial thickness of the roll remains. 
   It is also conventional to dispense paper towels from a vertical stack of individual towels or from a horizontal roll that rotates about a horizontal axis. 
   It is desirable for the user to be informed when the paper reserve is low in dispensers of the above-described types. 
   Low-reserve indicators have been previously proposed for paper towel dispensers of the type wherein individual towels are arranged in a vertical stack (see U.S. Pat. No. 1,738,721), or in a horizontal roll (see U.S. Pat. Nos. 2,601,956 and 3,273,773). In U.S. Pat. No. 1,738,721, the low reserve indicator includes a follower roller which rests upon the top of the stack and travels downwardly as the stack is depleted. The roller is attached by a lever arm to a pointer which is visible through a window disposed in a upper portion of the dispenser housing. The pointer rotates as the roller descends, in order to traverse a space between an “empty” indicia and a “full” indicia. Shortcomings of such an indicator include the fact that the roller must be manually held in a raised state by an operator who is loading fresh towels in the dispenser, thus complicating the re-filling operation. Also, the lever must be relatively long in order to extend between the pointer and the roller when the roller is at its lowermost state, whereby the expense, weight, size etc. of the indicator are greater than would be desired. 
   In each of U.S. Pat. Nos. 2,601,956 and 3,273,773, a relatively long indicator arm must be provided in order to extend to an outer cylindrical periphery of a paper roll U.S. Pat. No. 2,601,956, or in order to extend along and past the entire longitudinal length of the paper roll U.S. Pat. No. 3,273,773. Such long elements increase the overall cost of providing a low reserve indicator mechanism. 
   Also, it will be appreciated that the low reserve indicators described above are not suitable to a vertically oriented roll, let alone a coreless roll whose towels are pulled from the inner periphery of the roll. 
   SUMMARY OF THE INVENTION 
   The present invention is directed toward a paper dispenser which comprises a housing and an indicator mechanism affixed to the housing. The housing includes an inner chamber configured to support a paper supply. The paper supply has a side that is formed by superimposed edge portions of paper from the paper supply. The indicator mechanism includes an indicator operably connected to a release mechanism. The indicator is movable between an retracted position and an indicating position. The release mechanism is pivotally biased away from the housing and is releasable in response to the paper supply being reduced below a predetermined amount. Upon release, the release mechanism causes the indicator to move to the indicating position. 
   Accordingly, the present invention provides an improved paper dispenser. Other objects and advantages will appear hereinafter. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     In the drawings, wherein like numerals refer to similar components: 
       FIG. 1  is a plan view of a dispenser. 
       FIG. 2  is a vertical sectional view taken along line  2 - 2  in  FIG. 1 , depicting an upright coreless roll of paper towels disposed within the dispenser, and a low-reserve indicating mechanism according to the present invention. 
       FIG. 3  is a bottom front perspective view of a low reserve indicator mechanism according to the present invention. 
       FIG. 4  is a rear top perspective view of the indicator mechanism depicted in  FIG. 3 . 
       FIG. 5  is a bottom front perspective view of a release portion of a release mechanism according to the present invention. 
       FIG. 6  is a front perspective view of an indicator sign of the indicator mechanism. 
       FIG. 7  is a front bottom perspective view of a pusher member of the indicator mechanism. 
       FIG. 8  is a front bottom perspective view of a base member of the indicator mechanism. 
       FIG. 9  is a front bottom perspective view of a supporting portion of a release mechanism of the indicator of mechanism. 
       FIG. 10  is a fragmentary vertical sectional view taken through the dispenser of  FIG. 1  with the indicator mechanism associated with a first roll of paper towels; 
       FIG. 11  is a view similar to  FIG. 10  after the indicator mechanism has indicated that the remaining quantity of towels in the roll is low. 
       FIG. 12  is a view similar to  FIG. 10  wherein the dispenser contains a roll of paper towels having a smaller outer diameter than the roll of  FIG. 10 . 
       FIG. 13  is a sectional view taken through two components of the low reserve indicator mechanism. 
       FIG. 14  is a fragmentary view of a sidewall of the dispenser taken in the direction of arrow A in  FIG. 2 , when the low reserve indicator mechanism indicates that the remaining quantity of paper towels on the roll is low. 
       FIG. 15  is a view similar to  FIG. 10  showing an alternative form of indicator mechanism. 
       FIG. 16  is a front elevational view of a paper towel dispenser of the type which dispenses towels from a vertical stack, the dispenser containing a low reserve indicator according to the invention. 
       FIG. 17  is a sectional view taken along line  17 - 17  in  FIG. 16  showing the low-reserve indicator in a retracted position. 
       FIG. 18  is a view, similar to  FIG. 17 , after a release mechanism of the indicator has been released in response to the paper stack descending below a predetermined level. 
       FIG. 19  is a view similar, to  FIG. 17 , of a dispenser of the type which dispenses towels from a horizontal roll. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   Depicted in  FIGS. 1 and 2  is a paper towel dispenser  10  which dispenses towels from a paper supply in the form of a coreless roll  16  of paper towels from an inner periphery  12  of the roll  16 . The dispenser housing includes an upright side wall  18 , a floor  20 , and a cover  21 , together forming an internal chamber  14  for housing the roll  16 . The floor  20  includes a central opening  22  through which the towels can be dispensed. 
   A rear side of the dispenser is to be affixed to a wall  24 , so that the central opening  22  is spaced from the wall. In a conventional manner, the dispenser  10  is split into front and rear sections  26 ,  28  about a vertical parting line, and the dispenser is hinged at  30  along a vertical side of the parting line, to enable the generally semi-cylindrically shaped front section  26  to be swung open about that hinge, whereby the roll  16  can be inserted. Afterwards, the centermost towel is pulled partially down through the opening, and the front section  26  is closed, whereupon the dispenser is ready to dispense. A releasable latch  31  of any suitable type is provided for securing the front and rear sections  26 ,  28  a closed state. 
   As the roll  16  becomes depleted, its radial thickness t becomes gradually diminished. In order to warn a user or custodian when the remaining number of towels in the roll reaches a low state, the low-reserve indicator  40  (also herein referred to as a “low reserve indicator mechanism”) is provided. 
   A first embodiment of the indicator  40 , depicted in  FIGS. 2-11 , comprises an upper housing  50  ( FIG. 8 ), a pusher member  60  ( FIG. 7 ), a release mechanism  70  including a release arm  80  ( FIG. 9 ) and a release slide  90  ( FIG. 5 ), and an indicator in the form of a sign  100  ( FIG. 6 ). 
   The upper housing or base  50  ( FIG. 8 ) is adapted to be fixed to an underside  26   a  of the dispenser, for example, by a double-backed adhesive (not shown) which can be attached to a top wall  52  of the upper housing  50 . Depending downwardly from the top wall  52  are two identical parallel side walls  54 , each including a pair of horizontal guide slots  56 , a curved, generally vertical guide slot  58 , and a pivot hole  59 . The guide slots  56  and  58  of each side wall  54  are horizontally aligned with respective slots of the other side wall  54 . Also depending from the top wall  52  is a leg  53  adapted to support a rear end of a coil spring  69  ( FIG. 13 ), as will be discussed. 
   The pusher member  60  ( FIG. 7 ) includes a top wall  62  disposed beneath the top wall  52  of the upper housing  50 , a pair of side walls  64  disposed parallel to, and inside of, the side walls  54  of the upper housing, and a front pusher arm or wall  65  depending downwardly from a front end of the top wall  62  and side walls  64 . The pusher arm  65  includes an aperture  66  for accommodating movement of the sign  100 , as will be explained. Projecting outwardly from the exterior surface of each of the side walls  64  are two guide pins  67 . Those guide pins  67  are slidably received in respective horizontal slots  56  of the upper housing  50  to define a pin-and-slot connection to enable the pusher member to slide relative to the base. A pivot hole  68  is situated at a rear end of each side wall  64  to support the release arm  80  of the release mechanism  70 . Depending downwardly from a front end of the top wall  62  is a leg  76  that supports a front end of the spring  69 . It will be appreciated that the spring  69  yieldably biases the pusher member toward the center of the housing for reasons to be explained. 
   The release arm  80  ( FIG. 9 ) includes a bottom wall  82  and two side walls  84  extending upwardly from the bottom wall  82 . The bottom wall  82  includes a rearwardly facing portion  83  which extends generally upwardly and rearwardly to enable the release arm to be cammed upwardly upon engaging a roll of paper towels when the dispenser is closed, as will be explained. Each side wall  84  includes a guide slot  86  extending in a generally front-to-rear direction. A front end of each guide slot  86  is open, whereas a rear end  87  thereof is closed. Each side wall  84  includes a hole  88  aligned with the respective pivot hole  68  of the pusher member  60 , whereby an axle  89  ( FIG. 12 ) can be inserted through the holes  68 ,  88  to establish a pivot connection enabling the release arm  80  to pivot up and down. The front end of the release arm  80  is thus able to move up and down. One or more torsion springs  91  (see  FIG. 12 ) are provided at the axle  89  to yieldably bias the release arm for counter-clockwise rotation as viewed in  FIG. 12 . 
   The release slide  90  ( FIG. 5 ) includes side walls  94  and a connector  92  interconnecting rear ends of the side walls  94 . Projecting outwardly from a rear end of each side wall  94  is a guide projection in the form of a rectangular-shaped pin or lug  96  that is slidably disposed in the respective slot  86  of the release arm  80  to define therewith a pin-and-slot connection. A projection in the form of a guide pin  97  projects laterally outwardly from each side wall  94  at a location forwardly of the guide pin  96 . The guide pins  97  extend through respective guide slots  58  of the upper housing  50  to define therewith a pin-and-slot connection. Formed in the side wall  94  forwardly of the guide pin  97  is a slot  98  of generally U-shape. The slot  98  includes a central apex portion  98   a  and front and rear portions  98   b ,  98   c  extending generally upwardly from the apex portion. 
   The sign  100  ( FIG. 6 ) includes a body  102  having a pair of laterally projecting pivot pins  104  mounted in respective ones of the pivot holes  59  of the upper housing to enable the sign  100  to swing between a rear (retracted) position ( FIG. 10 ) and a forward or indicating (extended) position ( FIG. 11 ). The sign also carries pins  106  disposed in the slots  98  to form therewith a pin-and-slot connection. A front face  108  of the sign  100  carries indicia, such as the word “LOW” which is visible to a user or custodian when the sign is in the forward position (see  FIG. 14 ). 
   To enable the indicia to be visible, the front section  26  of the dispenser housing is preferably formed of a transparent material, such as a tinted acrylic. Alternatively, a window could be formed in the front section  26  through which the indicia could be seen. 
   In operation, the coreless roll  16  of paper towels is mounted in an upright state within the internal chamber  14  of the dispenser. When the front section  26  of the dispenser is then closed, the indicating mechanism (which is fixed to the underside  26   a  of the front section  26  of the dispenser) approaches cylindrical outer periphery of the roll  16 . In this state, the pusher member  60  will be in its right-most position, that is, closest to the center of the dispenser, under the urging of the spring  69  (see  FIG. 13 ). Also, the release arm  80  will be in its lowermost position, due to gravity, aided by the force of the torsion spring  91  ( FIG. 12 ). As a result, the inclined rearwardly facing portion  83  of the bottom wall of the release arm  80  of the release mechanism  70  abuts an upper edge  16   a  of the roll  16  and is cammed upwardly thereby. Hence, the release arm  80  is caused to pivot upwardly against the bias of the torsion springs  91  about a pivot axis defined by the axle  89 . Eventually, the release arm  80  comes to rest on an upper surface  16   b  of the roll  16 , as shown in  FIG. 10 . 
   It will be appreciated that the release mechanism accommodates rolls of varying height (that is, longitudinal length), because of the ability of the release arm  80  to pivot upwardly. That is, the extent to which the release arm swings upwardly will be dependent upon the height of the roll  16 . The greater the roll height, the greater will be the distance by which the release arm  80  swings upwardly. 
   When the front pusher arm  65  of the pusher member  60  abuts an outer periphery  16   c  of the roll  16  it may be pushed radially outwardly thereby, against the bias of the spring  69  ( FIG. 13 ), by a distance dependent upon the diameter of the roll  16 . In the embodiment according to  FIGS. 10-11 , the roll  16  of maximum diameter has been installed, whereby the pusher member  60  has been displaced to its maximum outer position wherein the guide pins  67  of the pusher member  60  are disposed at the front end of the guide slots  56  of the base. 
   If the roll  16  had been of a smaller outer diameter, as depicted in  FIG. 12 , wherein a smaller diameter roll  16 ′ has been installed, the pusher member  60  ( FIG. 3 ) would not have been displaced radially outwardly (that is, to the left) as far as in  FIGS. 10 and 11 . Also, the guide pins  96  of the release slide  90  would be situated farther outwardly (to the left) in the guide slots  86  of the release arm  80  in  FIG. 12 . Thus, the reason for making the release mechanism  70  of two parts  80  and  90  is to enable rolls of different outer diameter to be accommodated. 
   In any event, it will be appreciated that since the release arm  80  is mounted on the pusher member  60 , the final position of that release arm  80  is dependent upon the final position of the pusher member  60 . 
   In the state shown in  FIG. 10 , the guide pins  106  of the sign are captured in the rear portion  98   c  of the guide slots of the release slide  90 , and the sign  100  is held in the rear (retracted) position. 
   As towels are removed from an inner periphery  16   d  of the roll, the radial thickness t of the roll diminishes. Eventually, the inner periphery reaches a lowermost portion  82   a  of the bottom wall  82  of the release arm  80 , whereafter an inclined, forwardly facing portion  85  of the release arm  80  contacts the upper rear edge  16   e  of the roll  16 . Eventually, the thickness t′ is so thin, for example, one-eighth of an inch, that the upper edge  16   a  of the roll travels radially outside of a front end of the forwardly facing portion  85 . Accordingly, the release arm becomes unsupported and drops downwardly about the axis of the pivot pins, due to gravity (see  FIG. 11 ). As that happens, the release slide  90  swings downwardly with the release arm, whereupon the guide slots  98  force the guide pins  106  of the sign  100  forwardly until the sign comes to rest in the forward position, so that the user or custodian can see the “LOW” indicia (see  FIG. 14 ). 
   It will be understood that since the release arm  80  is mounted on the pusher member  60  and moves together therewith, the distance between the pusher arm  65  and the roll-contacting point on the bottom wall  82  of the release arm  80  will remain essentially constant during the towel dispensing phase, regardless of the horizontal location of the pusher member  60 , that is, regardless of the outer diameter of the roll. Thus, the sign  100  will always provide a low reserve indication in response to the same value of t′. 
   It will be appreciated that the low-reserve mechanism according to the present invention enables a user or custodian to be warned of a low-reserve state of an upright roll of paper towels in a dispenser. Furthermore, the low-reserve mechanism automatically adjusts to the height and outer diameter of the upright roll. 
   Also while it has been mentioned that springs can be provided to bias the release arm  80  downwardly, it may be possible to dispense with those springs and rely upon gravity alone if the design is such that insufficient friction will be generated that could cause the release arm to become hung-up. 
   It will also be appreciated that the feature of the invention wherein the low-reserve mechanism automatically adjusts to the roll diameter is optional. That is, the release mechanism, instead of being formed of two relatively movable parts  80 ,  90 , could be formed of a single member, as shown in  FIG. 15 . That is,  FIG. 15  shows an indicating mechanism  40 ′ wherein the release mechanism  70 ′ comprises a single element pivotably connected to a stationary upper housing  50 ′ which also carries a pusher member  65 ′ that abuts the outer periphery of the roll  16 . The release mechanism  70 ′ carries guide slots  98 ′ in which guide pins  106 ′ of the sign  100 ′ slide. The indicator mechanism accommodates a roll of a given outer diameter and does not possess the ability to accommodate rolls of different outer diameter as does the mechanism of  FIGS. 1-14 . 
   The present invention can also be used to provide a low-reserve indication for towel dispensers of the type in which towels are dispensed from a paper supply in the form of a vertical stack or a horizontal roll. In that regard, attention is directed to  FIGS. 16-18  depicting a dispenser housing  200  of the type which dispenses paper towels  202  disposed in a vertical stack. The dispenser includes a fixed first section  204  that is fixed to a wall (not shown), and a hinged second section (door)  206  that is connected to the first section  204  by a hinge (e.g., along an upper edge or a vertical side edge) to open and close a chamber formed by the dispenser housing. The stack of towels  202  (preferably interfolded towels) is supported such that at each end of the stack, vertically superimposed edge portions of the towels form a vertical side  208  that faces in a horizontally outward direction. The housing also forms a dispensing aperture at a lower end of the chamber for dispensing towels one-at-a-time. 
   A low-reserve indicator mechanism  210  according to the invention is affixed within the chamber to an upright wall  212  defined by the door  206  for indicating when a remaining (reserve) quantity of towels in the stack is low. The indicator mechanism includes a base member  214  affixed to the upright wall  212 , an indicator  216  mounted to the base member  214  for rotation about a horizontal axis  215   a , and a release mechanism  218 . The base member is similar to the previously described upper housing  50  in that it includes a pair of parallel side walls  220   a ,  220   b . The indicator  216  includes a sign  222  that bears the indicia “LOW”, and a crank arm  234 . The release mechanism comprises pair of parallel arms  218   a  (only one arm being depicted) interconnected by a pin  240 . 
   The side walls  220   a ,  220   b  of the base member  214  are situated between the arms  218   a , and the indicator  216  is situated between the side walls  220   a ,  220   b . The pin  240  is slidably and rotatably disposed in identical first slots  242  formed in respective side walls  220   a ,  220   b  and is spring-biased in a direction of bias by tension springs  244  (only one shown), each of which extends between the pin  240  and a fixed joint  246  on the respective side wall  220   a ,  220   b.    
   The crank arm  234  of the indicator  216  is pivotably connected to respective ones of the arms  218   a  by respective pin-and-slot connections, and defined by a pin  250  that extends through a second slot  252  formed in the respective side wall  220   a  or  220   b.    
   In use, an operator opens the door  206 , inserts a new stack of paper towels  202 , and re-closes the door. When the door is closed, the arms  218   a  of the release mechanism engage the vertical side  208  of the stack and are pushed to the retracted position shown in  FIG. 17 , against the bias of the spring  244 . Simultaneously, the indicator  216  is swung to a position shown in  FIG. 17  wherein the sign  222  is spaced from a window  256  formed in the wall  212 . When the stack of towels becomes so depleted that the vertical side  208  of the stack descends to a level below the arms  218   a , the arms  218   a  are released and swung by the springs  244  to a release position shown in  FIG. 18  in a direction causing the sign  222  to be swung toward the window  256  in order to expose the “LOW” indicia as shown in  FIG. 16 . 
   The low-reserve indicator mechanism  210  can also be used in connection with a conventional dispenser that dispenses towels from a roll of paper towels  260  which rotates about a horizontal axis  262 , as shown in  FIG. 19 . The towels are separated from the towels  260  by the user, for example, by forcing the paper against a conventional cutter (not shown) formed on the dispenser housing. The paper in the roll has vertically superimposed edge portions that form a vertical side  264  that is contacted by the arms  218   a  of the release mechanism in the manner disclosed above. When the roll is depleted to such an extent that the vertical side  264  descends below the point of contact with the arms  218   a , the “LOW” indicia of the sign  222  becomes visible outside of the dispenser housing. A wall  266  shown in  FIG. 19  could be a side wall of the dispenser housing. The arms  218   a  could be automatically pushed to the retracted position in response to the application of a force thereto from the towels  260  as the roll is being loaded. 
   The low-reserve indicator is small light-weight, inexpensive and can be automatically placed in a retracted state in response to the loading of paper, or closing the dispenser. 
   It will also be appreciated that the low-reserve indicator mechanism  210  could assume many different configurations for achieving its intended advantages. 
   While the invention has been described with reference to exemplary embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best or only mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims. Also, in the drawings and the description, there have been disclosed exemplary embodiments of the invention and, although specific terms may have been employed, they are unless otherwise stated used in a generic and descriptive sense only and not for purposes of limitation, the scope of the invention therefore not being so limited. Moreover, the use of the terms first, second, etc. do not denote any order or importance, but rather the terms first, second, etc. are used to distinguish one element from another. Furthermore, the use of the terms a, an, etc. do not denote a limitation of quantity, but rather denote the presence of at least one of the referenced item.