Patent Publication Number: US-9895033-B2

Title: Dispenser apparatus with damper for dispensing paper toweling

Description:
TECHNICAL FIELD 
     This invention relates to dispenser apparatus for dispensing paper toweling from a roll thereof. 
     BACKGROUND OF THE INVENTION 
     It is known generally to provide a damping system in roll paper towel dispensers to absorb the shock that occurs when roll overspin slack is taken up, thereby preventing “tabbing” during use of the dispenser. 
     Tabbing occurs when a piece of towel tears off the sheet when a user grasps and pulls the paper. Tabbing may occur with one or two hand pulls. Papers that absorb water at the greatest rate are most likely to tab. The rate of water absorbency varies by paper manufacturer and grade. Premium grade papers tend to absorb water the quickest and are generally harder to cut which leads to a higher rate of tabbing. 
     Tabbing takes place when overspin slack is taken up. A “shock” is present at the moment the overspin slack is exhausted. The shock occurs because the stationary roll towel must begin rotating at the moment the overspin slack is exhausted. The shock is greatest with full rolls and diminishes as the roll is exhausted. 
     U.S. Pat. No. 7,500,420, issued Mar. 10, 2009, discloses dispenser apparatus for dispensing paper toweling that includes structure for damping forces applied to a roll of paper toweling when overspin slack is taken up and wherein the timing of a cutter blade incorporated in the dispenser apparatus is modified to reduce peak pull force during dispensing. A biased damping roller is displaceable by the toweling when the toweling is pulled to take up the slack and maintain the toweling in taut condition between the end being pulled and the roll. 
     Paper companies continue to introduce bigger, heavier rolls with smaller core diameters and in some cases proprietary roll support plugs. Paper companies, for example, currently are making paper toweling rolls 10 inches in diameter and having 1,500 feet of paper. 
     This creates an even greater challenge when dealing with overspin. The biased damping roller approach disclosed in U.S. Pat. No. 7,500,420 may not be adequate to effectively control overspin in certain bigger, heavier rolls. 
     Overspin can create the following negative dispensing issues for dispensers including self cutting mechanisms, such as drum mounted tear blade systems, an example of which is disclosed in U.S. Pat. No. 7,500,420. 
     Among the problems is double sheeting. This can happen in two ways. One, on fast pulls the drum can over-rotate, dispensing the next sheet still attached to the first. 
     Two, the overspun toweling has no tension against the tear blade, which can reduce cutting effectiveness. 
     Another problem is the tabbing discussed above caused by the shock force created to get the roll spinning. 
     These problems were addressed by the invention disclosed in co-pending U.S. patent application Ser. No. 14/468,440, filed Aug. 26, 2014, which includes a rotary damper operatively associated with structure of a dispenser apparatus for dispensing toweling from a roll thereof. The term “toweling” as employed therein includes paper towels and toilet tissue. 
     The rotary damper resists rotation of the roll during dispensing to prevent overspin. 
     More particularly, according to one embodiment of the invention disclosed in application Ser. No. 14,468,440, the rotary damper, which may be of any suitable type, such as a geared type or a suitable non-gear type such as a viscous shear type damper, is located at the roll support arm or other roll support. 
     In other embodiments of the rotary damper is at the toweling sheet support drum or at an intermediate roller of a dispenser. 
     Benefits of the invention of application Ser. No. 14/468,440 include (a) overspin control and (b) reduced double sheeting by preventing the mechanism from free spinning. 
     It has been found that with large diameter heavy rolls it is necessary to use a heavier damper to control overspin while the roll diameter is large. This can create a problem, for example when the roll diameter decreases to around 4 inches and the drum return spring of the dispenser doesn&#39;t have enough energy to overcome the frictional drag created by the damper, resulting in short tails and eventually no tails. Overspin slack formation can be a problem for virtually any type of paper toweling dispenser where toweling from large diameter rolls is subjected to pulling forces. 
     DISCLOSURE OF INVENTION 
     The present invention provides a solution to this issue by disconnecting the damper when the roll diameter decreases to a selected lower size. A damper usually isn&#39;t needed when the roll diameter has been reduced to this size because the inertia of the roll is low. 
     The paper toweling dispenser apparatus of the present invention is for dispensing paper toweling from a roll of paper toweling and resisting formation of paper toweling overspin slack. 
     The term “toweling” as employed herein includes paper towels and toilet tissue. 
     The apparatus includes roll support structure for supporting a roll of paper toweling with said roll of paper toweling being rotatable relative to said roll support structure when a pulling force is applied to said paper toweling. 
     A rotary damper is operatively associated with the roll support structure and alternatively has an operative condition wherein the rotary damper substantially or wholly prevents formation of overspin slack in the paper toweling resulting from the pulling force and an inoperative condition. 
     Control mechanism is operatively associated with the rotary damper to change the rotary damper from the operative condition to the inoperative condition responsive to reduction of the diameter of roll of paper toweling during dispensing of paper toweling therefrom. 
     Other features, advantages and objects of the present invention will become apparent with reference to the following description and accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a perspective view illustrating a back cabinet portion and selected structural operating components of the dispenser apparatus of the present invention including a rotary damper on a roll support arm supporting a roll of toweling; 
         FIG. 2  is an enlarged, perspective view of the damper arm assembly of the invention including the support arm, a geared roll support hub located at the outer surface of a housing of the roll support arm, and a portion of a roll engagement member; 
         FIG. 3  is an enlarged, perspective view of the roll support arm as viewed from the outer side thereof, the housing interior of the housing accommodating a rotary damper; 
         FIG. 4  is a top view in partial cross-section showing a full roll of paper toweling supported by roll support arms with a roll engagement member in engagement with an end of the full roll; 
         FIG. 5  is a view similar to  FIG. 4 , but showing the roll of paper toweling in reduced diameter, the roll engagement member no longer engaged with the end of the roll which results in disengagement of the rotary damper from roll support hub; 
         FIG. 6  is an exploded, perspective view as viewed from the inner side of the roll support arm of  FIGS. 1-3  illustrating selected components including disassembled roll support hub, the rotary damper, a damper holder and roll engagement member; 
         FIG. 7  is a view similar to  FIG. 6 , but illustrating the selected components as viewed from the outer side of the roll support arm; 
         FIG. 8  is a cross-sectional, perspective view showing portions of selected components of the invention when the damper gear is disengaged from the geared hub; and 
         FIG. 9  is a view similar to  FIG. 8 , but illustrating the damper gear engaged with the geared hub. 
     
    
    
     BEST MODE FOR CARRYING OUT THE INVENTION 
     Referring now to the drawings, dispenser apparatus constructed in accordance with the teachings of the present invention is illustrated. The invention includes a cabinet  10 , only the rear cabinet portion thereof being shown. Attached to the rear cabinet portion are roll support arms  12 ,  14  utilized to support a roll of paper toweling  16 . In  FIGS. 1 and 4  the roll is at full diameter condition as is the situation when the roll is positioned in the cabinet and dispensing of toweling therefrom has not yet occurred. 
     A plug or hub  20  ( FIGS. 4 and 5 ) supports the end of the roll of paper toweling closest to support arm  14 . The hub is positioned in a cylindrically shaped support arm portion  22  which projects inwardly from the rest of support arm  14 . Hub  20  rotates with roll of paper toweling  16 . Alternatively, the hub may be affixed to or part of support arm  14 , with the roll rotatable thereabout. 
     The roll support structure at the other end of the roll is different. Support arm  12  includes a housing  24  which extends from both sides of support arm  12 . The outwardly extending portion of the housing  24  has an enlarged opening  26  which communicates with a housing interior  28  surrounded by a cylindrical wall. 
     The inner portion of housing  24  has an end wall  30 . A boss  32  extends inwardly in the direction of the roll of paper toweling and defines a screw hole passageway. A hub  34  is positioned over boss  32  and is rotatable relative thereto. A screw  36  is employed to maintain the hub  34  in place on the boss while allowing rotation thereof relative to the boss. 
     The hub  34  is inserted into the end of the roll of paper toweling closest to support arm  12  and rotates with the roll of paper toweling. Ribs  38  on the hub  34  help maintain the hub in fixed position relative to the roll of paper toweling. Gear teeth  44  are formed at the inner cylindrical wall of hub  34 . An opening  46  is formed in end wall  30  adjacent to boss  32 . 
     The apparatus includes a rotary damper  50  of any suitable type operatively associated with the roll support structure described above, the rotary damper alternatively having an operative condition wherein the rotary damper substantially or wholly prevents formation of overspin slack in the paper toweling within the cabinet resulting from a pulling force and an inoperative condition. 
     The rotary damper  50  is positioned in a damper holder  52 . Damper holder  52  has guide pins  54  which engage a track structure  56  within housing interior  28 . The damper holder and rotary damper are movable relative to the track within the housing  24  between a first rotary damper position when the rotary damper is in the operative condition and a second rotary damper position when the rotary damper is in the inoperative condition. 
     The rotary damper  50  includes a rotary gear component  60 , the rotary gear component is connected to the hub gear teeth when the rotary damper is in its operative condition. This condition is shown in  FIG. 9  wherein the rotary gear component extends outwardly through opening  46 . Outward movement of the damper holder and rotary damper within the housing  24  causes the rotary gear component  60  and the gear teeth  44  of hub  34  to disengage as shown in  FIG. 8 . Of course, when such disengagement occurs, the rotary damper will no longer resist rotation of roll of paper toweling  16  and hub  34 . 
     Control mechanism is operatively associated with the rotary damper to change the rotary damper from the operative condition to the inoperative condition responsive to a certain amount of reduction of the diameter of the roll of paper toweling caused by dispensing of paper toweling therefrom. 
     The control mechanism includes a movably mounted roll engagement member engageable with the roll of paper toweling. The rotary damper (within holder  52 ) is movable from the operative condition to the inoperative condition when the roll engagement member senses that the diameter of the roll of paper toweling has been reduced to a predetermined value. 
     The roll engagement member is a double-ended engagement lever  64  engageable with the end of the roll of paper toweling.  FIG. 4  shows such condition. The rotary damper and damper holder are connected by a pin  65  to the engagement lever at a location spaced from the end thereof engageable with the end of the roll of paper toweling. 
     The engagement lever  64  pivots about pin  66  and a spring  68  continuously urges the engagement lever for movement in a clockwise direction as shown in  FIGS. 4 and 5 . The spring shown is a torsion spring but any suitable type of spring, including a plastic spring integral with the engagement lever, may be utilized. When the diameter of the roll of paper toweling decreases to a certain value, for example 4.5 inches, the spring will urge the engagement lever to the position shown in  FIG. 5  and cause disengagement of the rotary gear component of the rotary damper and the hub gear teeth  44 . The roll of toweling will then rotate more readily.