Abstract:
A paper dispenser has a brake for a paper roll and a tensioning device for the web of paper and interacts in such a manner that the braking effect of the brake is adapted to the tension in the web of paper. The tensioning device is loaded in a paper path between the two conveying rollers and the paper reel.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This is a continuation application, under 35 U.S.C. § 120, of copending international application No. PCT/AT2009/000138, filed Apr. 8, 2009, which designated the United States; this application also claims the priority, under 35 U.S.C. §119, of Austrian patent application No. A 704/2008, filed May 5, 2008; the prior applications are herewith incorporated by reference in their entirety. 
    
    
     BACKGROUND OF THE INVENTION 
     Field of the Invention 
     The invention relates to a paper dispenser, in particular for hygiene papers or the like. 
     Since dispensers of this type and the reels to be inserted therein of toilet papers, paper towels, etc. are not precision products, widely varying rolling properties are unavoidable. It is particularly unfavorable here if the reels are too easy-running, since too much paper can be pulled off in the case of manual removal and, in the case of existing discharging mechanisms, continued rotation of the reel can lead to loop formation in the interior which can of course bring about functional disruptions. There are therefore also various simple brakes, for example hoops which press against the circumference, brackets which press against the end sides, etc., which, however, have disadvantages above all if the braking operation becomes too intensive. 
     SUMMARY OF THE INVENTION 
     It is accordingly an object of the invention to provide a paper dispenser which overcomes the above-mentioned disadvantages of the prior art devices of this general type. 
     With the foregoing and other objects in view there is provided, in accordance with the invention a paper dispenser. The paper dispenser contains a brake for a paper reel, two conveying rollers defining a nip therebetween, a paper path of a paper web leading through the nip between the two conveying rolls, and a tensioning device for the paper web. The tensioning device interacts with the brake, and the tensioning device is loaded in the paper path between the two conveying rollers and the paper reel. 
     The invention then proposes in a paper dispenser to allow a brake for a paper reel and a tensioning device for the paper web which comes from the reel to interact in such a way that the braking action of the brake is adapted to the tension in the paper web. 
     This means that, in the case of a low tension in the paper web which could have the consequence of sagging or the risk of a loop, the braking force on the paper reel is increased, it being possible for the paper reel to be rotated only with an increased force application during the next paper removal, as a result of which the paper sagging is eliminated at the beginning. The paper web is therefore increasingly tensioned, that is to say the tension in the paper web is increased, which, according to the invention, leads to the reduction in the braking action, with the result that the paper reel becomes more easy-running again. 
     The result of this is that an equilibrium will be set, that is to say the tension and the braking action are substantially in balance. The tensioning device can be loaded by gravity or preferably by a spring, with the result that every installation arrangement becomes possible. 
     The equalization according to the invention between tension and braking action is particularly advantageous in the case of paper dispensers which, in addition to the dispensing reel, have a reserve reel and a device for transferring the paper web of the reserve reel into a conveying roll nip as soon as the dispensing reel is exhausted. Precisely during the transfer of the reserve reel, there should be a sufficient rotational resistance at the reserve reel until the ratio of tensioning force and braking force has evened out. 
     There is provision in one preferred embodiment for the tensioning device to have a pivotable, U-shaped hoop and for the brake to have a brake lever which presses on the front side onto the reel and can be actuated by a side part of the hoop. The brake lever is provided, for example, on a rocker which is provided with a rising rib, onto which the side part of the hoop runs. If the side part moves in the opposite direction, the brake is loosened. 
     There is provision in a further preferred embodiment for a lever to project from the side part of the hoop, which lever is coupled kinematically to the cover of the dispenser by a bracket in such a way that, when the cover is open, the tensioning device is pivoted out of the paper path and the brake is released. The pivoting out of the tensioning device facilitates the insertion of the paper reel and the assignment of the start of the paper web to the device for transferring the paper web as soon as the dispensing reel is exhausted. If the cover is subsequently closed again, the hoop pivots until the paper web is tensioned. If the pivoting goes beyond an equalized center position, the brake is also engaged. 
     Other features which are considered as characteristic for the invention are set forth in the appended claims. 
     Although the invention is illustrated and described herein as embodied in a paper dispenser, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims. 
     The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING 
         FIG. 1  is a diagrammatic, side view of one preferred embodiment of a paper dispenser with an open cover, without a side wall, according to the invention; 
         FIG. 2  is a diagrammatic, side view of a detail from  FIG. 1  with a closed cover; 
         FIG. 3  is a diagrammatic, sectional view taken along the line III-III shown in  FIG. 1 , 
         FIG. 4  is a diagrammatic, center longitudinal sectional view through the paper dispenser according to  FIG. 1 ; 
         FIG. 5  is a diagrammatic, sectional view according to  FIG. 3  through the position shown in  FIG. 4 ; and 
         FIG. 6  is a diagrammatic, perspective view of the paper dispenser according to  FIG. 2 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring now to the figures of the drawing in detail and first, particularly, to  FIGS. 1 and 6  thereof, there is shown a dispenser for paper from at least one reel  13 . The dispenser has a housing  1  with a cover  2  which can be pivoted upward and moves a bracket  28  via a gear mechanism which has tooth segments  3 ,  29 , in which bracket  28  a slot is provided. The slot is penetrated by a pin which is arranged on a lever  27  which can be rotated about an axis  26 . Here, the lever  27  projects from a side part  17  of a U-shaped hoop  30  which forms a part of a tensioning device  15  for a paper web  25  and can likewise be pivoted about the axis  26 . A tensioning roller  16  is arranged rotatably on the transverse part of the hoop  30 , which tensioning roller  16  pivots into the path of the paper web  25  in a manner which is loaded by gravity or preferably by a spring  21 . 
     The side part  17  engages over a rocker  18  ( FIG. 3 ,  FIG. 5 ) which can be pivoted about an axis and has in each case one rising rib  19  and  20  on both lever arms. When the side part  17  moves to and fro about the axis  26 , it actuates the rocker  18 , as can be seen from the comparison of the two  FIGS. 3 and 5 . That arm of the rocker  18  which carries the rib  19  represents a brake lever which can press with a brake shoe  23  against the front side of the reserve reel  13 . 
     When the cover  2  is open, as can be seen from  FIG. 1 , the bracket  28  is pulled upward and the tensioning device  15  is deflected to the left about the axis  26 , since the side part  17  and the lever  27  project from one another approximately at right angles. The side part  17  has run onto the rib  20  of the rocker  18  and holds the latter in the position which is shown in  FIG. 3  and in which the brake shoe  23  is raised up from the braking position. 
     A reserve reel  13  is inserted, and the start of the paper web  25  is guided through behind the pivoted outward tensioning roller  16  and is fixed on a device  22 , the purpose of which is to thread the paper start of the reserve reel  13  into a nip  6  between two conveying rolls  4  and  5  when the dispensing reel  10  shown in  FIG. 2  is exhausted. The position of that component of the device  22  which is important for this purpose is indicated in  FIG. 4 . 
     If the cover  2  is then closed, the bracket  28  is moved downward and releases the U-shaped hoop  30  of the tensioning device  15  (see  FIG. 2  and  FIG. 6 ), the tensioning roller  16  of which presses onto the paper web  25  which is held in the conveying roll pair  4 ,  5 . The paper web  25  is tensioned, it being possible for the position of the tensioning device  15  to vary between the position shown in  FIG. 2  and the position shown in  FIG. 4 . In the approximately central position according to  FIG. 2 , the brake shoe  23  of the rocker  18  bears only lightly against the front side of the reserve reel  13 , with the result that the latter is braked from not at all to only a little. If the reserve reel  13  rotates too easily, paper is pulled off from the tensioning device  15 , and the tensioning device  15  pivots further to the right under the action of the spring  21 , which increases the pressure of the brake shoe  23  on the reserve reel  13 , since the side part  17  runs onto the rising rib  19 . The tension in the paper web  25  increases and an equilibrium is set between tension and braking force. 
     If paper is conveyed by the conveying roll  4 ,  5 , the tensioning device  15  will pivot back to the left and the brake will loosen a little if the braking action is too high, and will move further to the right and increase the brake pressure if the braking action is too low. In any case, uncontrollable unraveling of the paper web  25  from a reserve reel  13  which runs too easily is avoided. 
     The paper dispenser according to the invention can have a dispensing reel  10  and a reserve reel  13 , the paper of which is taken over by the device  22  after exhaustion of the paper of the dispensing reel  10  and is fed to the conveying rolls  4 ,  5 , with the result that paper can continue to be removed and the refilling can take place not at this instant, but rather at some later time before exhaustion of the reserve reel. 
     The equalization of the braking action to a changing paper tension is by nature independent of the presence of the dispensing reel, with the result that the dispenser can also be of smaller and simpler construction, by it being possible for all the components which are required only for the dispensing reel and the paper change to be omitted. The reserve reel is then the dispensing reel, and it goes without saying that the uncontrolled unraveling in the housing is also to be avoided in this case.