Abstract:
A braking assembly used in a dispenser that dispenses a continuous supply of material such as paper. The braking assembly includes a support structure. A first fixed gear is rotatably connected to the support structure. A movable chassis is also connected to the support structure. A second movable gear is held by the chassis and moves with the chassis. Teeth of the first gear and teeth of the second gear intermesh with each other and allow the paper to pass therethrough. The chassis maintains the teeth of the first and second gears in contact with each other while enabling a distance between gears to be adjustable. The assembly further includes a braking mechanism that varies an amount of force required to rotate the gears.

Description:
FIELD OF THE INVENTION 
     The present invention relates to a braking assembly for a continuous feed material dispenser. 
     BACKGROUND OF THE INVENTION 
     Continuous feed material dispensers often dispense from a central location at the bottom of the dispenser. Usually the material being dispensed is a paper material, such as paper towel wound onto a roll. The roll of paper towel might be perforated to assist in determining a length of material dispensed. 
     In regards to perforated center-feed paper towel dispensing, most prior art dispensers use a funnel shaped orifice that acts as a brake by controlling the tension on the towel as it is dispensed. See, for example, U.S. Pat. No. 6,769,589 to Paukov. 
     As a towel is pulled from the dispenser, it is forced through an opening that becomes increasingly narrower which requires an increase in the force applied by the user to pull the towel through the narrow end. The orifice is sized such that the force applied by the user to remove the towel increases to an amount higher than the perforation strength of the towel or web material. Continued pulling causes the web to break and provides the user with a single section of towel. 
     One problem with this method of dispensing is that the orifice needs to be sized to match the properties of the web material being used and it is not easily adjusted to adapt to materials with different properties. Another problem, due to small variations inherent in the manufacturing of web materials (perforation tensile strength, paper weight, etc.) as well as other external factors, is that it is possible that a sheet of material breaks off from the continuous source of the material at a point within the funnel such that it does not leave any additional material protruding from the orifice for the next user to pull. 
     These types of dispensers can also be difficult to load once the web has been broken or when the supply of material has been exhausted and a new supply must be loaded. The person responsible for reloading the dispenser must try and push a section of the flexible web material through the funnel, at which point the material tends to bunch up on itself as more material is pushed in to move it along the funnel. As more material is fed in and it reaches the narrower end of the funnel, this bunching can effectively clog the orifice the user is trying to load into. 
     SUMMARY OF THE INVENTION 
     It is therefore, an object of the present invention to provide a braking assembly for a continuous feed material dispenser that addresses and ameliorates, in whole or in part, one or more of the above-noted disadvantages. 
     The dispenser according to the invention utilizes two feed gears. In a presently preferred embodiment, one gear is rigidly mounted and the other is moveably mounted to a chassis which is spring loaded to keep the gears meshed together without jamming, regardless of the basis weight of the paper. 
     Additionally, in a presently preferred embodiment, the braking assembly utilizes an adjustable brake which can be used to increase the amount of force required to turn the feed gears, thereby allowing a user to adjust the dispenser to the appropriate force level for the perforation strength of the material being dispensed. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Preferred embodiments of the invention will be described by way of example with reference to the attached drawings, in which: 
         FIG. 1  is an exploded perspective view of components of an embodiment of a braking assembly; 
         FIG. 2  is a perspective view from above of the  FIG. 1  embodiment assembled in a dispenser; 
         FIG. 3  is a perspective view from above of the  FIG. 1  embodiment assembled in a dispenser, with certain parts removed for clarity; 
         FIG. 4  is a perspective view from above of the  FIG. 1  embodiment shown apart from the dispenser; and 
         FIG. 5  is a perspective view of the braking assembly of the  FIG. 1  embodiment. 
     
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
     In the drawings, reference numeral  10  denotes a braking assembly according to the present invention. The braking assembly  10  is connected to a dispenser main housing (not shown). The main housing is configured to hold a supply of continuous feed material that is to be dispensed from the main housing. As recognized by those of ordinary skill in the art, the term “continuous feed material” includes paper, non-woven webs and other absorbent web material. This feed material might be wound in a roll or might be folded. The feed material might also be perforated or non-perforated. For the sake of convenience, the term “paper” is used below. However, the present invention is not limited to such material and each of the above noted materials and other feed materials known in the dispensing art are contemplated by the invention. 
     In the embodiment of  FIG. 1 , the braking assembly  10  includes a braking assembly housing  20  (see  FIG. 2 ) having a lower assembly housing  22  and an upper assembly housing  24 . 
     A first gear  30  is mounted in the braking assembly housing  20 . The first gear  30  rotates about a first axis  30 A that extends longitudinally through a center of the first gear  30 . The first gear  30  includes a rotation axle  32  that enables rotation of the first gear  30  about the first axis  30 A in axle support  26 ,  27  in the lower assembly housing  22 . 
     The lower assembly housing  22  also supports a chassis  40  at chassis supports  28 ,  29 . In a presently preferred embodiment, the chassis  40  is pivotally mounted in chassis supports  28 ,  29  via first and second chassis ends  41 ,  43 . However, the chassis  40  might also be mounted for linear movement, or might move by a combination of linear and pivoting motion. The chassis  40  preferably includes an elongate main body  42  having the first and second ends  41 ,  43  and first and second arms  44 ,  46  extending substantially perpendicular to the elongate main body  42 . 
     A second gear  50  is mounted on the chassis  40  between the first and second arms  44 ,  46 . The second gear  50  rotates about a second axis  50 A that is parallel to the first axis  30 A. In a presently preferred embodiment, the chassis  40  pivots about a third axis  40 A spaced apart from and parallel to the second axis  50 A. The second gear  50  has teeth  55  that intermesh with teeth  35  of the first gear  30 . An example of intermeshing teeth is disclosed in applicant&#39;s U.S. Pat. No. 6,089,401, the entirety of which is hereby expressly incorporated by reference. 
     The chassis  40  is configured to maintain the first and second gears  30 ,  50  adjacent to each other while enabling a distance between the first and second gears  30 ,  50  to be adjustable by the second gear  50  moving with the chassis  40 . In a presently preferred embodiment, torsions springs  70 ,  75  are connected to the first and second ends  41 ,  43  of the main body  42 . The torsion springs  70 ,  75  bias the chassis  40  so as to maintain the first gear  30  and the second gear  50  adjacent to each other. Such configuration of the chassis  40  enables a distance between the gears to be changed while the teeth  35 ,  55  are still engaged. This arrangement allows paper of varying thickness to flow through the first and second gears  30 ,  50  without jamming. 
     In a presently preferred embodiment, the configuration of the axle support  26  is such that the first gear  30  is prevented from movement except in rotation. In this embodiment, the above-noted chassis configuration enables the second gear  50  to move with the chassis  40 . However, the present invention contemplates that either or both gears  30 ,  50  are movable in directions other than in rotation. 
       FIG. 1  further shows a brake mechanism  60 . The brake mechanism  60  controls the amount of force required to spin the gears. In a presently preferred embodiment, the brake mechanism varies the force required to spin the first gear  30  and is adjustable throughout from a relatively low to a relatively high amount of force such that the brake mechanism  60  can accommodate paper product of various perforation strengths. The brake mechanism  60  can also be used to set a force such that the dispenser will dispense one segment of a continuous perforated sheet of paper or can be set to a lower force such that multiple segments can be removed without breaking the perforated material. The break force can be adjusted to meet the customers&#39; requirements for consumption with multiple varieties of paper of various perforation strengths. 
     In the presently preferred embodiment, the brake mechanism  60  includes a wave washer  62  as seen in  FIG. 5  mounted over the axle  32  of the first gear  30 . The wave washer  62  is held captivate between axle support  27  and a hub  64  on the end of the axle  32 . The brake mechanism  60  is held in place by a screw  66  threaded into the axle  32 . A flat portion on the underside of the head of the screw  66  abuts against the hub  64 . 
     Adjusting a length of thread engagement on the screw  66  causes the wave washer  62  to compress or allows it to expand. Increasing the thread engagement causes the wave washer  62  to compress and increases the axial force on the first gear  30 , which in turn requires a higher force to rotate the first gear  30 . Similarly, decreasing the screw engagement allows the wave washer  62  to expand and decreases the axial force on the first gear  30  allowing the first gear  30  to rotate more freely. 
     In other embodiments, the wave washer  62  might be replaced by a spring or a piece of resilient material  68  or any combination of these might be used such as would have the same effect of modifying the force required to rotate the gear through the compression and expansion of the resilient material. Additional components can be used to sandwich the resilient material to increase lubricity between the resilient material and the surfaces which hold the resilient material captive therebetween to reduce wear and extend the life of the braking mechanism  60 . 
     In the presently preferred embodiment, the braking mechanism  60  is connected to the first gear  30 . However, a braking mechanism might be connected to either the first gear  30  or the second gear  50 . Also, in other embodiments a brake mechanism could be installed on any other component in the “drive train” of the braking assembly  10  so long as the end effect would result in controlling the amount of force required for rotating the gears. 
     In one embodiment of the invention, there is a manual feed knob  80  that allows the user to advance the paper if the perforation breaks within the feed gears and there is no “tail” left showing for the next portion of paper. The manual feed knob  80  might also be used to ease loading of the leading end of a fresh roll of material through the braking assembly  10 . In a presently preferred embodiment, the manual feed knob  80  turns along an axis  80 A perpendicular to the axes of rotation  30 A,  50 A for the first and second gears  30 ,  50 . This is accomplished utilizing a bevel gear train comprising beveled gear  82  of the manual feed knob  80  and beveled gear  34  of the first gear  30 . This setup allows a narrower profile for the dispenser as well as utilizing a gear ratio to optimize the force required to actuate the manual feed knob  80  for ergonomic factors. 
     In alternative embodiments, the feed knob might rotate along an axis parallel with the first and second gears  30 ,  50  either through a gear train or by direct attachment to one of the first and second gears  30 ,  50 . Additionally, the manual feed knob  80  might be shaped in such a way that an end user can only gain an effective grip on the knob for turning in the prescribed direction. 
     As best seen in  FIGS. 3 and 4 , the braking assembly  10  might also include anti-reverse features. As recognized by those of ordinary skill in the art, the braking assembly  10  of the present invention is designed to dispense paper from a paper source to an end user. To keep the braking assembly  10  from being able to run counter to the designed direction, in a presently preferred embodiment, there is a gravity actuated pawl  90  that rotates on an axis  90 A parallel to the axes of rotation  30 A and  50 A for the first and second gears  30 ,  50 . Pawl  90  is arranged such that as material is being dispensed, the first gear  30  rotates away from the free end  92  of the pawl  90 . If the first gear  30  were to attempt to spin in a direction towards the pawl  90 , the pawl  90  will engage one of the teeth  35  of the first gear  30  preventing the first gear  30  from further rotation in that direction. Although a pawl is described herein, nevertheless, as recognized by those of ordinary skill in the art, other mechanisms might be used to ensure that the braking assembly  10  rotates in only one direction. 
     While the present invention has been described in connection with various preferred embodiments thereof, it is to be understood that those embodiments are provided merely to illustrate the invention, and that the invention might readily be varied within the scope of the appended claims.