Abstract:
A hands-free paper product dispenser has three separate IR emitter and sensor circuits, two controlling the length and/or number of sheets of paper cut and dispensed, and the third used both to safety interlock the cutter mechanism and to control retention of each cut sheet by the dispenser until removed from the dispenser by a user. A novel cutting mechanism and associated upper and lower pinch plates are employed to both hold the paper during cutting and assure a straight and unfrayed cut.

Description:
BACKGROUND OF INVENTION 
     Many consumable products are manufactured in the form of spirally-wound rolls, e.g., paper towels and gift wrap. While these products can be unwound from the roll entirely by hand, there are a number of devices in the prior art to aid in dispensing product from the roll. These range from simple support of the roll, such as a single upright spindle upon which the axis of the roll is vertically installed, to cabinets into which a product roll is placed and which have mechanisms for dispensing product. 
     For simplicity of further discussion, and because the most common product roll dispensed is paper or similar nonwoven web material, the terms “paper,” “paper towel” and “paper towel roll” will be used hereinafter instead of “product” and “product roll.” However, it should be understood that the present invention can be adapted to virtually any spiral-wound sheet product. 
     U.S. patents to Byrd, et al., specifically U.S. Pat. Nos. 5,772,291, 6,105,898 and 6,293,486, disclose electrically-driven paper dispensers incorporating a photocell which causes a motor to unroll paper when an object (such as human hand) blocks light entering it. One patent (U.S. Pat. No. 4,738,176) combines electrically-actuated unwinding with electrically-actuated cutting; a bi-directional motor moves the paper when turning in one direction and cuts it when turning in the other direction. 
     However, until the issue of U.S. Pat. No. 6,994,408 to the present inventor, the prior art did not provide the user separate hands-free control of the amount of paper dispensed and the timing of cutting the paper off. Another problem with the art prior to U.S. Pat. No. 6,994,408 was that either the paper was released before the user is ready to take it, or the user had to pull so hard to take the paper from the machine. 
     Yet another problem with the art prior to U.S. Pat. No. 6,994,408 was that many dispensers were designed to handle only one specific paper, e.g., thin, low-cost hand towels. If other paper grades were used in these types of dispensers, feed and cutting problems may have resulted. 
     Yet another problem with dispensers of the art prior to U.S. Pat. No. 6,994,408 was that parts driven at high speed were stopped by surfaces, such as bumpers, in the machine, which led to excessive noise and impact wear. There was also room for simplifying mechanisms for the holding of the paper by machine parts during and after cutting, which were addressed by U.S. Pat. No. 6,994,408 and are improved by the present invention. 
     Other needs addressed by the present invention are reduction in operating noise and vibration, and reduction in the number of, and increase and simplicity of, parts necessary to move, cut, and hold the roll product. 
     The present invention also adds safety features, and embodiments providing novel dispensing capabilities. 
     SUMMARY OF INVENTION 
     The invention described here is a novel cutting and handling mechanism for electric-powered dispensers of spirally-wound materials such as paper towels, which uses novel mechanics and electronic circuits to position, unroll, and cut towel material, and to interlock those operations. It also uses novel structures to cut, guide, and hold material. Other embodiments add dispensing capabilities, both preset and user-variable, cabinet structures, and installation options. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a perspective view of a first, preferred, embodiment of present invention from the upper left front. 
         FIG. 2  is a perspective view of a second embodiment of the present invention in which the preferred embodiment is installed in a generic cabinet. 
         FIG. 3  is another perspective view of the preferred embodiment from the upper left front after paper has been advanced. 
         FIG. 4  is a left side view of the preferred embodiment in the same state as in  FIG. 3 . 
         FIG. 5  is a perspective view from the upper left front of the preferred embodiment during the leftward pass of the cutting sequence. 
         FIG. 6  is a left side view of the preferred embodiment in the same state as in  FIG. 5 . 
         FIG. 7  is a left side view of the preferred embodiment in the same state as in  FIG. 6  showing additional elements. 
         FIG. 8  is a left side view of the invention after the leftward pass of the cutting sequence. 
         FIG. 9  is a left side view of the invention after the rightward (return) pass of the cutting sequence short of the home position. 
         FIG. 10  is a perspective view from the upper left front of the invention in the same state as  FIG. 9 . 
         FIG. 11  is a left side view of the invention after cut product is pulled from the invention. 
         FIG. 12  is a left side view of the invention being tilted fully forward for paper loading. 
         FIG. 13  is a circuit diagram of the first embodiment of the paper cutting and control mechanism of the preferred embodiment. 
         FIG. 14  illustrates an exploded perspective view from the lower left rear of a second embodiment of the invention which includes a cabinet. 
         FIG. 15  is a detail perspective view of the power interlock parts of the second embodiment. 
         FIG. 16  is detail perspective view of the right tube section of a special bearing of the second embodiment. 
         FIG. 17  is a cross-sectional detail of the special bearing of the second embodiment. 
         FIG. 18  is an exploded view of the means by which the cabinet of the second embodiment is held in the closed position. 
         FIG. 19  is the first part of an operational flow diagram of the method performed by the first and second embodiments of the invention. 
         FIG. 20  is the second part of an operational flow diagram of the method performed by the first and second embodiments of the invention. 
         FIG. 21  is the first part of an operational flow diagram of the method performed by a third embodiment of the invention. 
         FIG. 22  is the second part of an operational flow diagram of the method performed by a third embodiment of the invention. 
         FIG. 23  is the third part of an operational flow diagram of the method performed by a third embodiment of the invention. 
         FIG. 24  is the first part an operational flow diagram of the method performed by a fourth embodiment of the invention. 
         FIG. 25  is the second part an operational flow diagram of the method performed by a fourth embodiment of the invention. 
         FIG. 26  is the third part of an operational flow diagram of the method performed by a fourth embodiment of the invention. 
         FIG. 27  is a perspective view from the upper left rear of a fourth embodiment of the present invention, which includes a stand for portable applications. 
     
    
    
     DETAILED DESCRIPTION 
     Referring now to the attached drawings, in which like features are represented by like reference characters in each of the drawings,  FIG. 1  is a perspective view of the preferred embodiment of the present invention from the upper left front. The invention is a novel cutting and handling mechanism for electric-powered dispensers of spirally-wound materials such as paper towels, in which the leading end  90  of a wound strip of paper  1  (shown in large dashed lines to indicate environmental structure) is unwound to a user-selected length past a horizontal stationary paper cutting blade  9 , whence it is cut horizontally at a user-selected time and held gently between a lower backing plate  11  and a lower pinch plate  12  until extraction by the user. The preferred embodiment of the invention is assembled as a module  103  comprising all of the parts described and illustrated below unless otherwise excluded. Construction of the invention in modular form enables the invention to be housed in a variety of cabinets or drawers, and enables each module to be tested before it is incorporated into a final product. The module  103  is typically to be housed in a cabinet (e.g., such as depicted in  FIG. 2 ) into which a product roll such as a roll of paper towels may be loaded. It should be understood, while looking at this and the following figures, that unless otherwise indicated, the stationary parts herein described are fixed to a common support structure which may in turn be enclosed in a cabinet. 
     It should also be understood that the description and scope of this invention is meant to include its mirror image, i.e., that left and right may be interchanged throughout. 
     The leading portion of paper  1  from such a product roll is shown having been fed manually into a nip (better visible in the following side views, see  FIG. 3 ) between a drive roller  2  and idler rollers  3 . One drive roller and two idler rollers are depicted here, but the scope of the description and claims of the invention is meant to include any number of drive or idler rollers on common axes. 
     The idler rollers  3  press the paper  1  against the drive roller  2  under their own weight and that of idler shaft  17 , bearing against inclines  18  on cutaways of shaft support structure  19 . A cutter carousel  4  is shown at its home position at the far right, with its case  5  cut away to show a circular paper cutting blade  6 , a pinion  91 , and a rubber o-ring  7  mounted on a cutter dowel pin  8 . 
     A substantially vertical upper pinch plate  20  (cutaway to show other parts), a cutaway portion of a rack  92  fixed to the upper pinch plate  20 , and an upper backing plate  10  are also shown, the function of which are explained further below. 
     The carousel  4  is moved horizontally left and right by a belt (not shown) driven by an electric cut motor  200  as is known in the art. Novel to the art, however, is that the circuitry controlling the horizontal positioning of the carousel  4  is designed in such a way that when voltage is initially applied to the invention (“power-up”), the carousel is moved to this home position in a manner dependent on its initial position before power-up (see  FIGS. 19 and 20 ). 
     This view also shows a lower pinch plate opening  101  near the central portion  42  of the lower pinch plate  12 , the function of which will be explained below in  FIG. 6 . 
     Also visible in cutaways in this view are the left and right ends of carousel rail  14  and a portion of the common support structure  15 , from which lower pinch plate catch arm  16  extends rearward. 
       FIG. 2  is a perspective view from the upper left front of a generic cabinet  130  into which a module  103  of the preferred embodiment of the present invention (not visible in this view) has been installed. (The preferred embodiment combined with a cabinet  130  constitutes a second embodiment, as discussed more fully beginning with  FIG. 14 .) It shows a left recess  23  and a right recess  24 , across each of which is projected an electromagnetic beam (e.g., infrared (IR) light) through four lenses  25  (two of which are on the opposite sides of the recesses and are therefore not visible in this view). 
     Paper  1  has been advanced downward by a user breaking an electromagnetic beam (not visible) projected across the right recess  24  by putting his/her hand in the right recess  24  for an amount of time necessary to cause a desired length of paper  1  to appear below the cabinet  130 . As explained in greater detail below, the paper  1  is cut by a user breaking a second electromagnetic beam (not visible) projected across the left recess  23  by putting his/her hand in the left recess  23  for any amount of time, however short, as long as the beam is broken. 
       FIG. 3  is another perspective view of the preferred embodiment from the upper left front of the invention. In this view, the paper  1  has been advanced by drive roller  2  to an arbitrary length below the invention. A drive motor  30  (see  FIG. 4 ) runs as long as the beam is broken and stops when the user&#39;s hand is withdrawn. It should be noted that the stationary paper cutting blade  9 , the upper backing plate  10  and the lower backing plate  11  are fixed to stationary modular components (not shown for clarity) of the invention. The upper pinch plate  20  and the lower pinch plate  12 , however, are suspended rotationally about the upper pinch plate dowel pins  21  (only left pin is visible in this view) and the lower pinch plate dowel pins  22  (only left pin is visible in this view). This allows the upper and lower pinch plates to move forwardly (arrow A) and backwardly (arrow B) about horizontal axes passing through the dowel pins, as further described below. 
     This figure illustrates some additional functions performed by the carousel  4  in its home position. While in this position, both the upper pinch plate  20  and the lower pinch plate  12  are opened as far forwardly as they will go relative to the upper backing plate  10  and the lower backing plate  11 , respectively, so as to provide the widest possible opening for the paper  1  to advance through. The upper pinch plate tends to rotate forwardly (counterclockwise about the upper pinch plate dowel pins  21  in this view) due to its own weight distribution, and its forward travel is thus at a maximum, limited only by an abutment  33  fixed to the carousel  4 . Similarly, the lower pinch plate  12 , which is normally biased rearwardly (counterclockwise about the lower pinch plate dowel pins  22  in this view) by a spring (not shown) is held forwardly to the maximum extent, against the spring bias, by a lower pinch plate release foot  35  fixed to the bottom of the case  5  of the carousel  4 . When the carousel  4  is in its home position, the release foot  35  presses downwardly on a lower pinch plate release pad  13  fixed to the right end of the lower pinch plate  12 , which rotates the lower pinch plate  12  clockwise about the lower pinch plate dowel pins  22 . 
     In this view it can also be seen that idler rollers  3  come into contact with either paper  1  or drive roller  2  through rectangular cutouts  23  in the upper pinch plate  20 . Thus the upper pinch plate  20  does not interfere with the rotation of the idler rollers  3 . 
       FIG. 4  is a left side view of the preferred embodiment of the present invention in the same state as in  FIG. 3  (home position) showing the drive motor  30  and worm gear  31  engaged to drive roller  2 , which has just advanced the paper  1  through nip  32  to a user-selected length. The upper pinch plate  20  is shown resting lightly against the carousel abutment  33 , and the left end of the idler shaft  17  is shown as being supported rotatably on the left incline  18  on the left cutaway of the shaft support structure  19 . (The right end of the idler shaft  17  is similarly supported by like parts at the other end of the shaft  17 .) 
     Also notable in this view is that the circular paper cutting blade  6  is behind (in this view) the paper  1 , and the rubber o-ring  7  is behind the upper pinch plate  20 . Because the carousel  4  is in its home position, as explained below in more detail, and because of the positioning of the upper pinch plate  20  against the carousel abutment  33 , the paper  1  is permitted to hang freely in the open space between the upper backing plate  10  and the upper pinch plate  20  and in the open space between the lower backing plate  11  and the lower pinch plate  12 . 
     In the development of the present invention, it was discovered that optimal paper cutting action occurs when the plane of the circular paper cutting blade  6  and the axis of the cutter dowel pin  8  are tilted clockwise as viewed from the front of the invention by about 5 degrees (thus exposing the lower surface  36  of the circular paper cutting blade  6  to view as shown). It has also been found that cutting action is further enhanced by tilting the stationary paper cutting blade  9  downward toward the front of the invention (toward the right in this view) by about 5 degrees. 
     This figure also shows significant additional elements of the carousel  4  and their function. It can be seen in this view that carousel  4  is supported for horizontal travel left and right (out of and into the page in this view) from below by a carousel rail  14 . The carousel  4  rides on the upper surface  39  of the carousel rail  14  by means of an upper guide wheel  37  rotating on the horizontal axis of an upper guide wheel dowel pin  38 , and rides on the rear surface  312  of the carousel rail  14  by means of a lower guide wheel  310  rotating on the vertical axis of a lower guide wheel dowel pin  311 . The carousel rail  14  is prevented by the support structure  15  from moving up or down at both ends, but is allowed to move backwards and forwards against the support structure  15  at both ends by rail springs  44  (only the left rail spring  44  is shown in this view). 
     Finally as to  FIG. 4 , note that the rearmost end  313  of catch arm  16  has upward-extending abutments  314  on it which are placed so as to engage and release the center of the lower pinch plate  12 , under conditions explained in more detail further below. 
       FIG. 5  is a perspective view from the upper left front of the invention during the leftward pass of the cutting sequence. As the carousel  4  starts moving to the left, the rubber o-ring  7  contacts the upper pinch plate  20  before the circular paper cutting blade  6  begins to cut the paper  1 . This is because of the diameters selected for the circular paper cutting blade  6  and the rubber o-ring  7 , and the distance that the right hand edge of the paper  1  is positioned to the left of the right hand edges of the upper pinch plate  20  and the lower pinch plate  12 . Thus, before any paper cutting takes place, the upper pinch plate  20  is pushed rearward by the rubber o-ring  7 , pinching the paper  1  against the upper backing plate  10 . Friction of the o-ring  7  against the upper pinch plate  20  also serves to drive the circular paper cutting blade  6  clockwise (as viewed from above) about the cutter dowel pin  8 . 
     Optionally, a pinion  91  may be installed upon the cutter dowel pin  8 , for the purpose of engaging a rack  92  fixed to the front side of the upper pinch plate  20  to provide positive forced rotation of the circular paper cutting blade about the cutter dowel pin  8 . 
     Also occurring as the carousel  4  leaves its home position, the lower pinch plate release foot  35  moves leftwardly off of the lower pinch plate release pad  13 , allowing the lower pinch plate  12  to rotate rearwardly, pinching the paper  1  against the lower backing plate  11 . This upper and lower pinching of the paper prevents the paper from bunching as it is cut. Furthermore, because the rubber o-ring  7  is of smaller diameter than the circular paper cutting blade  6 , the rearward edge  40  of the circular paper cutting blade  6  is forced to move rightward relative to the stationary paper cutting blade  9 , which adds a rightward shear component to what would otherwise be a purely rearward shear component against the paper  1 . These two effects produce an extremely clean cut and minimize the creation of paper dust. 
     Finally as to  FIG. 5 , note that because the lower pinch plate  12  has rotated to the rear (under the rearward bias of a spring, not shown) a notch  41  near the central portion  42  of the lower pinch plate  12  has rotated forwardly about the axis of the lower pinch plate dowel pin  22 , against the upward-extending abutments  314  on the catch arm  16 . The central portion  42  of the lower pinch plate  12  thus applies more pinching force against the paper  1  than is applied to the paper  1  by the remainder of the lower pinch plate  12  whenever the carousel  4  is not in its home position. Note the slight rearward bowing of the upper edge  50  produced by this effect. 
       FIG. 6  is a left side view of the preferred embodiment of the present invention in the same state as in  FIG. 5 . It shows a view of the lower pinch plate  12 , cutaway to show again the bowing effect of the notch  41  pressing against the upward-extending abutments  314  on the catch arm  16 . The purpose of holding the paper  1  against the lower backing plate  11  only at the central portion  42  constitutes a twofold improvement over the prior art: (a) the cut portion of the paper is more gently held at the center than if it is held by the entire width of the lower pinch plate  12 , and thus may be removed by even less force than required by the prior art; and (b) by being held at the center, the cut paper is less likely to sag to one side or the other. 
     This view also shows that the carousel upper guide wheel  37  and the lower guide wheel  310  remain in contact with the midpoint of the carousel rail  14 . The rail springs  44  assure that the o-ring  7  will contact the upper pinch plate firmly, and cause the carousel rail  14  to exert a rearward force on the lower guide wheel  310  at all horizontal locations of the carousel  4 . This has the added beneficial effect of applying a clockwise (in this view) torque on the carousel  4  about the point of contact between the o-ring  7  and the upper pinch plate  20 , causing the rearward edge  40  of the circular paper cutting blade  6  to press upwardly against the horizontal paper cutting blade  9 . This further assures a clean cut. 
     The pinion  91  is also shown engaged to the rack  92  in this view. 
       FIG. 7  is a left side view of the preferred embodiment of the present invention in the same state as in  FIG. 6  showing additional elements. A portion of the carousel  4  has been cut away to show a control element for the lower pinch plate  12  and the carousel  4 . It comprises an infrared (IR) light-emitting diode (LED)  63  fixed to the rear support structure  15  of the invention, emitting a beam of IR light  61  forward, a lower pinch plate opening  101 , a lower backing plate opening  62 , and an IR sensor  60  fixed to a front part of the support structure  15 . At this time in the cutting cycle, namely during the leftward pass of the carousel  4  (toward the reader in this view) the lower pinch plate  12  is pressing the paper  1  against the lower backing plate  11 . Thus the beam of IR light  61  is blocked temporarily by the paper  1  from striking the IR sensor  60 . 
       FIG. 8  is a left side view of the invention after the leftward pass of the cutting sequence, at which time the carousel  4  is as far as it will go toward the reader in this view. Note that the paper  1  is now fully cut, producing a cut paper portion  80 , both of which are now to the right of (behind in this view) the circular paper cutting blade  6 . Note also that the central portion  42  of the lower pinch plate  12  is still being bowed against the cut paper portion  80  by the abutments  314  pressing rearwardly against the notch  41  in the lower pinch plate  12 . 
       FIG. 9  is a left side view of the invention after the rightward (return) pass of the cutting sequence. Even though the paper  1  has been cut completely, the cut portion of the paper  80  is still held by the central portion  42  of the pinch plate  12 . This is because once the abutments  314  engage the notch  41 , it cannot be released from the abutments  314  until the lower pinch plate release pad  13  on the right end of the lower pinch plate  12  is pressed downward by the lower pinch plate release foot  35  at the bottom of carousel  4 . On its rightward travel (into the page) after cutting the cut portion of the paper  80 , the electronic circuitry controlling the motion of the carousel  4  does not allow it to travel all the way to its home position as long as the IR beam  61  is stopped by the cut portion of the paper  80 . 
     In addition, and importantly for safety reasons, the electric circuitry provides that if the IR beam  61  is not stopped by paper (at any stage of operation) the cut motor  200  is prevented from performing the cut operation. In practice this means that if an object is inserted into the machine when paper is not present below the cutter blades, accidental cutting cannot occur. 
       FIG. 10  is a perspective view from the upper left front of the invention in the same state as in  FIG. 9 , better showing the position of the lower pinch plate release foot  35  of the carousel  4 , being stopped just to the left of the lower pinch plate release pad  13 . 
       FIG. 11  is a left side view of the invention as the cut portion of the paper  80  is pulled from the invention. In  FIGS. 8 and 9 , the fully-cut portion of the paper  80  was held gently between only the central portion (not visible in this view) of the lower pinch plate  12  and the lower backing plate  11 . In  FIG. 11 , as soon as the cut portion of the paper  80  is pulled far enough downward by the grasp of a user  102  (shown in large dashed lines to indicate an environmental feature) to allow the IR beam  61  to reach the IR sensor  60 , the electronic circuitry causes the carousel  4  to be driven fully to the right (into the page). This causes the lower pinch plate release foot  35  to pass rightward onto the lower pinch plate release pad  13 , pressing it down. The lower pinch plate release pad  13 , being fixed at its rear end to the lower pinch plate  12 , causes the lower pinch plate  12  to rotate clockwise in this view about the lower pinch plate dowel pins  22  (only left pin is visible in this view), thereby causing the lower pinch plate  12  to release all hold on the cut portion of the paper  80 . The rubber o-ring  7  (and the optional pinion  91 ) will also now be out of contact with the upper pinch plate  20  (and, respectively, the optional rack  92 ) allowing the upper pinch plate  20  to swing forward and release the uncut paper  1  to be rolled downward again when desired by a user. 
       FIG. 12  is a left side view of the invention being tilted so that its front (to the right in this view) is fully downward for paper loading. Typically, the invention is installed in a cabinet (see, for example,  FIG. 14 ) that supports the stationary parts of the invention on an axis  1414  at the rear and on a latch  180  at the front (see  FIG. 18 ). When the front latch is released, the invention swings downward into the position shown. Note that the amount of forward incline of the invention is now such that the inclines  18  on cutaways of shaft support structures  19  (only the left-hand ones being visible here) are tilted downward toward the front (to the right in this view) thereby allowing the idler rollers  3  and the idler shaft  17  to move forwardly along the incline  18 . This creates the opening shown here between the drive roller  2  and the idler rollers  3 , allowing the leading end  90  of the paper  1  to be fed manually between them before the cabinet is closed. 
       FIG. 13  is a circuit diagram of the first embodiment of the paper cutting and control mechanism of the preferred embodiment of the present invention. To the greatest extent possible, the electronic circuitry is in the form of printed circuit boards, which are programmable to permit changing, e.g., timing parameters. The circuitry provides that whenever system voltage rises above zero, namely, whenever the cabinet is closed, the carousel is forced to the home position at the far right of the invention as seen from the front. This is important because if the carousel is not fully to the right after the cabinet is opened and re-closed, the rubber o-ring  7  may still be in contact with the upper pinch plate  20  (see  FIGS. 5 through 10 ) which would prevent paper from being fed past the cutting blades. 
     The circuitry also provides that when the cut cycle is activated, not only does the carousel start moving to the left, but also an electronic timer starts. If the cut motor fails to reach the left side within a predetermined time, power to the cut motor is cut off. This provides added safety in the event motion of the circular paper cutting blade is significantly impeded for any reason. 
     The present invention also improves the prior art by providing photo (e.g., IR) interrupter switches instead of magnetic or mechanical switches to control starting and stopping of the motors. 
       FIG. 14  illustrates an exploded perspective view from the lower left rear of a second embodiment of the invention, including a cabinet  130  as mentioned above, wherein the cabinet  130 , shown here in a cutaway perspective view, has an open top  131 , a rear end  132 , right and left sides  143  and  144  respectively, the right and left sides having upper edges  145 , a bottom  134 , and a front  135 , all forming a space into which a module  103  is installed, and comprising additional elements. In this embodiment, the cabinet  130  is rotationally suspended from a bracket  136  having substantially horizontal right and left bracket edges  137 , right and left collar supports  139  and  1310  respectively, and a front section  1311 . Right and left cylindrical collar holes  1312  and  1313  respectively, which are centered on a common axis  1314 , pass through the left and right collar supports  139  and  1310  of the bracket  136 . 
     In this exploded view, the cabinet  130  is shown at an angle such that the plane of the open top  131  is tilted downward toward the front  135  relative to the plane of the substantially horizontal bracket edges  137 , to allow insertion of a spirally-wound product roll (not shown) into the cabinet  130 . The cabinet  130  tilts downward and upward about the common axis  1314 , which is also common to cooperating right and left tube sections (only right tube section  1315  shown in this view) fixed to the right and left sides  143  and  144  respectively of the cabinet  130 . The right tube section  1315  has an outside diameter slightly smaller than the inside diameter of the right collar hole  1312  on the bracket  136 . The right tube section  1315 , inserted within the right collar hole  1312  (as well as the left tube section (not visible in this view) inserted within the left collar hole  1313 ) forms a special bearing (see ref.  140  in  FIG. 17 ) for gently lowering the cabinet  130  when it is opened, as shown more clearly in  FIGS. 16 and 17 . The cabinet  130  may be closed by raising the front  135  of the cabinet  130  so that its upper edges  145  are brought into substantial contact with the horizontal bracket edges  137 . 
       FIG. 14  also shows a left side window  1316  in left side  144  which allows a user to see how much spirally-wound product remains inside the cabinet  130 . A like window (not shown in this view) may be provided in the right side. Also depicted in  FIG. 14  is an important safety power interlock, comprised of an active contact  1317  affixed to the bracket  136 , and a passive contact  1318  affixed to the cabinet  130 . In this second embodiment, the active contact  1317  receives electric power via an adapter jack  1321 . 
       FIG. 15  is a detail perspective view of the power interlock parts of the second embodiment. The active contact  1317 , shown here attached to the inside of the bracket  136  in cutaway view from the lower left front, has two electrically-conductive active strips  1319  which are constantly charged with direct current (DC) voltage from a DC power adapter (not shown). The DC voltage is applied by a power adapter plug (not shown) through a jack  1321  on the rear side of the active contact  1317  (not visible in this view; see  FIG. 14 ). The passive contact  1318 , shown attached to the inside of the cabinet  130 , in cutaway view from the lower left rear, has two electrically-conductive passive strips  1320  which come into contact with the active strips  1319  only when the cabinet  130  is raised so that its upper edge  145  is brought into substantial contact with the bottom bracket edge  137 . 
       FIGS. 16 and 17  illustrate the special bearing  140  of the second embodiment referred to above in  FIG. 14 .  FIG. 16  is an enlarged detail perspective view of the inner, right tube section  1315  portion of the special bearing  140 , affixed perpendicularly to the inner surface of a cutaway of the right side  143  of the cabinet  130 , as shown in  FIG. 14 . This figure also better shows a special annular elastic damper  141  stretched around the distal end  160  of the right tube section  1315  portion of the special bearing  140 . These parts of the special bearing  140 , because they are attached to the cabinet  130  (see  FIG. 14 ), rotate clockwise in this view when the cabinet is opened and counterclockwise when it is closed.  FIG. 17  is a cross-sectional view of the entire special bearing  140  along Section A-A′ of  FIG. 16 , 
     including the right collar support  139  of bracket  136  (the rest of which is not visible in this view; see  FIG. 14 ). A mirror image of this special bearing exists in this second embodiment on the left side of the invention. The insertion of the right tube section  1315  into the right collar hole  1312  (see  FIG. 14 ) creates an annular space  170  which, because it is narrower than the original thickness of the elastic damper  141 , compresses the elastic damper. The right collar support  139 , being part of the bracket  136 , does not move, whereas the right tube section  1315  and right cabinet wall  143  rotate about the common axis  1314  when the cabinet  130  (the rest of which is not visible in this view; see  FIG. 14 ) is opened or closed. The elastic damper  141 , being slightly compressed between the right tube section  1315  and the right collar hole  1312 , yieldingly resists their relative rotation about the common axis  1314 . The selection of the shape of the annular space  170 , the type of elastic and the degree of interference in the fit determine the amount of torque needed to cause rotation of the right collar hole  1312  about the tube section  1315 . A certain shape, elastic material, and interference dimension provide the optimal torque that allow the cabinet  130  to open slowly enough to prevent noise and shock when opened, while not significantly increasing the effort a user must exert to close it. In addition, the second embodiment utilizes springs, as illustrated in the following figure, to provide a counter-torque to stop the opening rotation at a pre-selected point, beyond which the user may further open the cabinet if desired by application of manual downward pressure. 
       FIG. 18  is an exploded view of this second embodiment from the lower left rear, showing the means by which the cabinet  130 , shown here in the open position relative to the bracket  136 , may be held in the closed position. A latch paddle  180 , having a upper end  181  and a lower end  182 , is rotatably attached to the inner surface  183  of the front  135  of the cabinet  130  by an axle  184  affixed to the latch paddle  180  rotating within bearings  189  attached to the cabinet  130 . The upper end  181  of the latch paddle  180  is biased forwardly by a spring or other biasing mechanism (not shown) so that the lower end  182  of the latch paddle  180  is as far rearward against the structure of the cabinet  130  as it will go. The upper end  181  of the latch paddle  180  has a forwardly-projecting catch  185 , positioned so that when the cabinet  130  is raised to the closed position relative to the bracket  136 , the catch  185  follows the general path  186  to releasably engage a striker  187  affixed to the inner surface  188  of the front section  1311  of the bracket  136 . The cabinet  130  can be lowered when a user pulls the lower end  182  of the latch paddle  180  forward, at which time the catch  185  is moved rearwardly off the striker  187 , allowing the cabinet  130  to swing downwardly under its own weight. 
       FIG. 18  also shows a helical spring  190  having a bracket end  191  affixed to a point on the right side of the bracket  136  and a cabinet end  192  affixed to a point on the right side of the cabinet  130 . 
     Preferably, in the interest of balancing forces on the cabinet  130  and the special bearings  140 , a like spring (not shown) is attached to the opposite points on the left sides of the bracket and cabinet. By proper selection of the coefficient of elasticity of the helical spring  190 , a point will be reached by downward travel of the cabinet  130  at which the weight of the cabinet  130  is equaled by the combined tension on the springs  190 . 
       FIG. 19  is the first part of an operational flow diagram of the detailed method performed by the first and second embodiments of the invention (the second embodiment being the first, preferred embodiment housed in a cabinet with additional inventive elements). 
       FIG. 20  is the second part of an operational flow diagram of the method performed by the first and second embodiments of the invention. Portions of this diagram are linked to each other and to portions of  FIG. 19  wherever a status circle containing a certain capital letter has output arrows in one portion and input arrows in another. The method described by  FIGS. 19 and 20  taken together disclose all of the elements of the method of the first and second embodiments described earlier, plus additional detailed steps relating to precise positioning of the parts and fail-safe characteristics. 
       FIG. 21  is the first part of an operational flow diagram of the method performed by a third embodiment of the invention, in which the function of the breaking of the left and right electromagnetic beams has been changed from the “dispense on the right” and “cut on the left” mode described above in the first and second embodiments to a “dispense and cut to one length on the right” and “dispense and cut to another length on the left” mode. For example, breaking the right beam can be set to advance the paper to a 6″ length and cut it, and breaking the left beam can be set to advance the paper to a 12″ length and cut it. Other convenient pairs of lengths may be pre-set depending on the intended use of the invention. 
     As with the flow diagrams of  FIGS. 19 and 20 , portions of  FIG. 21  are linked to each other and to portions of  FIGS. 22 and 23  wherever a status circle containing a certain capital letter has output arrows in one portion and input arrows in another. 
     This third embodiment is physically identical to the first embodiment except for the electronic circuitry driving the moving parts. 
       FIG. 22  is the second part of the operational flow diagram of the method performed by the third embodiment. 
       FIG. 23  is the third part of the operational flow diagram of the method performed by the third embodiment. The circuitry can incorporate solely the logic of this embodiment, or, with the addition of a manual switch, can allow a user to change the operation of the hardware from the first embodiment to the third embodiment. The switch may be locked inside the cabinet of the second embodiment so that it may be actuated only by an authorized person. 
       FIG. 24  is the first part an operational flow diagram of the method performed by a fourth embodiment of the invention, in which the circuitry includes a key pad available to the user who may enter a desired length and quantity of sheets. Upon entering these parameters at status circle K in  FIG. 24 , the machine would begin to dispense and cut until the entered quantity value is satisfied. This can be accomplished in either of two ways: the user can withdraw each sheet as it is cut to release the cutter for the next cut, or the electronic circuitry can be programmed to disable the center LED interlock so that the carousel goes to the home position after each cut, opening the pinch plates and allowing each sheet to drop into a tray. The unit would still be operational in manual mode, that is, as in the first or second embodiments. 
     As with the preceding flow diagrams, portions of  FIG. 24  are linked to each other and to portions of  FIGS. 25 and 26  wherever a status circle containing a certain capital letter has output arrows in one portion and input arrows in another. 
     Again, this fourth embodiment is physically identical to the first embodiment except for the electronic circuitry driving the moving parts. 
       FIG. 25  is the second part the operational flow diagram of the method performed by the fourth embodiment. 
       FIG. 26  is the third part of the operational flow diagram of the method performed by the fourth embodiment. 
       FIG. 27  is a perspective view from the upper left rear of a fourth embodiment of the present invention, which includes a stand  270  for portable applications. The bracket  136  of the second embodiment is installed in the stand  270  and functions the same way. The stand  270  must be sufficiently high that when the cabinet  130  is opened, the bottom of the cabinet  130  does not strike the floor or other surface supporting the stand  270 .