Patent Document

CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation-in-part of application Ser. No. 13/849,574. 
     BACKGROUND 
     Field 
     This application relates to dental hygiene devices, specifically to powered dental flossers. 
     Prior Art 
     Dental flossing is one of the most important personal hygienic tasks. Flossing contributes to the preservation of teeth, gingival (gum) tissues, jaw bones, and general health. Yet, flossing is avoided by many because conventional methods are tedious, messy, and inefficient. Conventional floss frames supporting a fixed floss span are unhygienic because the floss span becomes septic upon first contact with dentition wherein the device must be frequently replaced. Some products claimed to be “flossers” power-rotate tiny bristles as a substitute for flossing, but this method can&#39;t deep-clean interdentally. Proper interdental hygiene requires removal of adherent material from under circumferential gum lines. Other than skilled professional cleaning, only correct flossing strokes using continuously replaced floss spans can suffice. 
     The patent records show several powered flossers intended to provide continuous automatic floss replacement (CAFR), but none have appeared on the market. A problem in common with CAFR flossers of record reviewed by this inventor is that during use, the used floss (septic floss) is dragged rearward behind the flossing tines to a take-up spool in or on the main body of the flossers. The septic floss contains bacteria and food debris that are difficult to sanitize and results in debris deposits, stains, and offensive odors. 
     SUMMARY 
     Embodiments of a more practical dental flosser, shown and described in this application, include a replaceable attachment that winds used floss on a take-up spool positioned over a flossing tine. This restricts used floss to the oral portion of the flosser for rapid disposal of spooled septic floss and expeditious reset of spooled fresh floss. Another attachment features built-in means for sanitizing the used floss and requires no floss-handling by the user. A power driver of the attachments includes a dual-shaft drive system that drives a flossing span to oscillate at high-speed transversely of the span while continuously replacing the span. 
     Advantages 
     Some attachment embodiments feature winding used floss at an anterior extremity where septic floss disposal is simple and efficient. The self-sanitizing attachment is maintenance-free. In all embodiments, simultaneous longitudinal and transverse motions of a floss span work the floss between tightly abutting teeth and under circumferential gum lines to remove debris and to polish teeth interdentally. 
    
    
     
       DRAWINGS 
       FIGS.  1 - 9   
       The accompanying drawings in combination with the description herewith illustrate features of embodiments. Like reference numerals in different views refer to the same parts. The drawings are not necessarily to scale. 
         FIG. 1  is a lateral side view of an automatic dental flosser including a power driver detachably connected to a detachable flossing attachment, both are shown partly in section taken through a longitudinal midline of the flosser. 
         FIG. 2  is an enlarged front view of the flosser of  FIG. 1 . 
         FIG. 3  is an enlarged fragmental rear view of a second flossing tine of the flosser of  FIG. 1 . 
         FIG. 4  is an enlarged top view of the detachable flossing attachment of the flosser of  FIG. 1 . 
         FIG. 5  is an enlarged top view, partly in section, of a floss take-up spool of the flosser of  FIG. 1 . 
         FIG. 6  is an enlarged fragmental side view of an anterior portion of the flossing attachment of the flosser of  FIG. 1  showing a floss cutting feature. 
         FIG. 7  is an enlarged fragmental side view of an anterior portion of a second embodiment of a flossing attachment showing an alternative floss take-up spool sectioned longitudinally along the spool rotational axis wherein the opposite spool half is removed. 
         FIG. 8  is an enlarged fragmental side view of an anterior portion of a third embodiment of a flossing attachment showing a floss take-up spool having high floss-holding capacity. 
         FIG. 9  is an enlarged side view, partly in section, of a fourth embodiment of a flossing attachment requiring no floss maintenance by the user. 
     
    
    
     DETAILED DESCRIPTION 
     FIGS.  1 - 6   
     First Embodiment 
     Beginning with  FIG. 1 , an embodiment of the automatic dental flosser  10  is shown including flossing attachment  12  detachably connected to power driver  14  that drives attachment  12 . Included in attachment  12  are a flossing arm  50  supporting flossing tines  46  and  48 , a floss supply spool  15 , floss take-up spool  17 , and floss  54  threaded through the attachment. 
     Components of driver  14  include a hollow plastic housing  70  forming a handle and having a lower semi-cylindrical chamber  16  and an upper semi-cylindrical chamber  18 . Tightly fitted in chamber  16  is a dual-shaft geared motor  20  having an anterior drive shaft  22  and a posterior drive shaft  24 . Chamber  18  is a holder of an electric power cell  26  for energizing motor  20  by way of a conventional electric circuit (not shown) open or closed by a momentary switch  28 . An actuating button  30  of switch  28  is accessible through an opening in chamber  18 . Button  30  is covered by a flexible plastic membrane  32  which is sealed water-tight by conventional means. Electrical wires and connectors (not shown) electrically connecting power cell  26 , switch  28 , and motor  20  are conventional. 
     A detachable end cap  11  covers an otherwise open posterior end portion of housing  70 . Cap  11  can be removed for replacing power cell  26 . A conventional rib-and-groove connector (not shown) detachably retains cap  11  in place and a rubber seal  13  around end rims of housing chambers  16  and  18  keeps moisture out. 
     Geared motor  20  includes a motor-driven speed-reduction gear train (not shown) contained in a gearbox  34 . The gear train drives anterior shaft  22  which has a hex-shaped cross section and serves as a key mated and detachably received in a hex-shaped keyway  36  in a flanged cylindrical plastic-molded connector  38 . Posterior shaft  24  drives an eccentric weight  40  fixedly mounted on shaft  24  by means of a set screw (not shown) or by being press-fitted. Eccentric weight  40  is positioned posteriorly of more than ¾ of the combined mass of all other components of the flosser including the power cell. 
     Flossing Attachment— FIGS. 1-6   
     Flossing attachment  12 , shown in  FIGS. 1-6 , is comprised of two assemblies; an outer assembly  42  ( FIG. 1 ) and an inner assembly  44 . Outer assembly  42  is comprised of a bifurcated member forming first flossing tine  46  positioned in front or anteriorly of second flossing tine  48 . The tines are spaced from each other and positioned at an anterior or front end portion of arm  50 . As shown in  FIG. 3 , second tine  48  defines a floss guide groove  52  that guides dental floss  54  to a distal end portion thereof. The tine distal end portion defines an aperture  56  through tine  48  wherein aperture  56  is directed toward opposite tine  46 . The distal end portion of tine  48  also defines an open-ended slot  58  having its open end at the distal end of tine  48 . Slot  58  enters in communication with aperture  56  by entering from a lateral side thereof as viewed when tine  48  is positioned vertically. Slot  58  and aperture  56  together are 9-shaped and serve for expeditiously attaching, guiding, and supporting floss  54  on tine  48  and for avoiding accidental detachment of the floss from tine  48 . 
       FIG. 2  shows that an anterior portion of first tine  46  is formed into two opposing floss shields  60  and  62  positioned proximate to take-up spool  17 . Shields  60  and  62  are spaced slightly apart for shielding used floss  54  passing between the shields as the floss is drawn from a distal end portion of first tine  46  to take-up spool  17 . Shields  60  and  62  extend anteriorly of tine  46  starting from a location indicated by a dashed line  64  in  FIG. 1 . The tine shields are substantially triangular-shaped wherein a side of the triangle proximate to spool  17  is parallel to a core  19  of spool  17 . The advantage of this arrangement is explained further on in this document. A proximal end portion of arm  50  includes a flange  66  formed to engage power driver  14 . Arm  50  with its flange  66  and tines  46  and  48  are formed as a one-piece plastic-molded combination. 
     Outer assembly  42  also includes a bracket  68  for detachably connecting flossing attachment  12  to power driver  14 . Bracket  68  is shaped to conform to plastic housing  70 . A hook-shaped front portion of bracket  68  is partially embedded in the molded plastic of flange  66  to fixedly secure arm  50  and bracket  68  together. As shown in  FIG. 4 , bracket  68  defines a U-shaped slot  72  for receiving a screw  74  ( FIG. 1 ) extending from driver housing  70 . A knurled nut  76  holds attachment  12  in place on driver  14  wherein a ring gasket  78  cemented around a rim of driver  14  forms a water-tight seal at the joint. Referring back to  FIG. 4 , flange  66  defines a multi-diameter central bore aligned with an open channel  80  extending longitudinally of arm  50  and ends at a distal end of the arm. 
     Inner assembly  44  is comprised of a flexible and resilient driven shaft  82  rotatably supported in the central bore in flange  66 . Driven shaft  82  extends longitudinally along channel  80  wherein an O-ring seal  84  seated in a recess in flange  66  and encircling shaft  82  prevents moisture from entering driver  14 . A proximal end portion of shaft  82  is fixedly and coaxially imbedded in a sleeve  86  ( FIG. 1 ) which is fixedly and coaxially imbedded in plastic connector  38 . 
     Referring to  FIG. 4 , rotatably supported on connector  38  is a floss supply spool  15  which includes a pair of floss retaining flanges  90  and  91  fixed to a hollow spool core fitting loosely around connector  38 . Spool  15  rotates independently of connector  38  by slipping around the connector. 
     Shown in  FIG. 5 , a distal portion of driven shaft  82  is fixedly received in a hollow tube or sleeve  93  which forms a hollow distal end portion of shaft  82 . Core  19  of take-up spool  17  is hollow for receiving the hollow distal end portion of shaft  82  fixed therein by a pin  21  passing through a transverse aperture through spool core  19  and through shaft  82 . Core  19  defines an open-ended core slit  94  therethrough that curves in a spiral-like manner longitudinally of spool core  19 . The hollow distal end portion of driven shaft  82  defines an open-ended linear slit  95  therethrough longitudinally thereof. The open end of spool core slit  94  is aligned with the open end of shaft slit  95 . Both slits  94  and  95  progressively diverge away from each other as they extend away from their open ends. They do so to form a floss gripper for enhanced gripping of floss  54  passing from tine  46  and transversely through both slits  94  and  95  to detachably connect floss  54  expeditiously to spool core  19  for being wound thereon. 
       FIGS. 1-3  show the route for threading floss  54  through flosser  10  starting at supply spool  15  as fresh floss. From spool  15 , floss  54  passes through a grommet  96  in bracket  68  and bends around flange  66  to pass over two guide posts projecting from a lateral side of arm  50  for guiding and supporting the floss. A slot at the crotch between arm  50  and tine  48  enables the floss to enter into and pass through the floss guides of second tine  48 . From tine  48  the floss forms a flossing span  47  between both tines and then travels between the flossing shields  60  and  62  to take-up spool  17 . 
     As used floss builds up on take-up spool  17 , the accumulating spooled floss will engage shields  60  and  62  of the bifurcated member. To accommodate expansion of accumulating spooled floss, flexible and resilient shaft  82  will be forced to temporarily bend slightly for repositioning spool  17 . In  FIG. 2 , the phantom image around spool  17  indicates a raised position of spooled used floss that will occur after a substantial increase of floss accumulation accommodated by the mentioned bending of shaft  82 . Hence, the anterior strand of floss  54  between shields  60  and  62 , and about to be wound onto spool  17 , is adequately shielded during all amounts of floss-winding on the take-up spool. 
     Referring to  FIGS. 4 and 6 , a user can dispose of the spooled used floss after flossing one or more times by simply pulling the spooled used floss off the distal end of spool  17 . To cut off the used floss, arm  50  includes a conventional floss cutter  29  hidden under a tongue-shaped guard  27  proximate to spool  17 . A proximal end portion  31  of guard  27  is molded to a distal end portion of arm  50 . Most of guard  27  is spaced from arm  50  to allow floss to slide under the guard to access cutter  29  for cutting off the used floss. The base of cutter  29  is attached to an underside of the guard by being imbedded in the molded plastic. The cutter&#39;s cutting blade is angled toward the open entry under the guard to receive and cut floss. Thus, floss can be gripped by the floss gripper in spool core  19  wherein the used portion of floss can then be cut off by cutter  29 . Both steps can be done in one or two seconds and the flosser will be ready for use again. 
     Controlling Tension of the Foss Span— FIGS. 1, 2 and 4   
     In  FIG. 2 , driver housing  70  includes opposing anterior lateral side walls  23  and  25 . Floss supply spool  15  is between walls  23  and  25  which have interior surfaces that are normally slightly spaced from flanges  90  and  91  of spool  15 . Walls  23  and  25  are molded from resilient plastic and sufficiently thin for temporarily bending inward under user hand pressure. Thus, a user can optionally finger-press the exterior of the driver housing such that at least one of the opposing side walls  23  and  25  temporarily bends inward. The walls will engage flanges  90  and/or  91  to produce selective rotation resistance of supply spool  15 . This enables user-selective tension of floss span  47 . The amount of pressure applied by the user&#39;s fingers against the walls determines the amount of floss span tension. Benefits of user-controlled floss-span tension are explained in the Flosser Operation section of this document. 
     Second Embodiment of a Flossing Attachment 
     FIG.  7   
     Shown in  FIG. 7  is a flossing attachment  12 B which is substantially the same as embodiment  12  except for replacement components described next. A plastic floss take-up spool  39 , that replaced spool  17 , receives a flexible and resilient replacement driven shaft  41  fixed into a hub bore passing longitudinally through an open-ended core  43  of spool  39 . Spool core  43  is cone-shaped progressively narrowing toward the open end. (For visability, spool  39  is sectioned longitudinally along the rotational axis wherein a removed opposite half of spool  39  is a mirror image of the one shown.) 
     Spool core  43  defines an open-ended linear slot  45  in communication with the core hub bore and partially divides core  43  longitudinally into opposed symmetrical core portions including core portion  51 . Starting from the open end of core  43 , slot  45  progressively narrows as the slot extends rearward away from the open end. The opposed core portions are designed to expeditiously grip floss between them for functions that include detachably connecting the floss to spool  39  for winding the floss. Thus, core  43  forms a floss gripper. 
     A floss grip enhancer  53  is positioned within the hub bore of core  43  and between the opposing core portions. When floss is drawn into slot  45 , grip enhancer  53  serves for detachably jamming or jam-gripping the floss between grip enhancer  53  and the inner surface of core  43 . Grip enhancer  53  is an elongate distal end portion of shaft  41  progressively narrowing to a dull point toward the open end of core  43 . Conversely, enhancer  53  progressively widens as the shaft extends away from the open end of core  43 . In addition, enhancer  53  defines closely juxtaposed longitudinal grooves  55  which result in splines, respectively, between the grooves along the tapered shaft to provide an anti-slip surface thereon for enhanced slip-resistant jam-gripping of floss for winding on spool  39 . 
     Operation of the High-Speed Dental Flosser 
     The components of flosser  10  are arranged such that a user that operates switch button  30  will have fingers holding the flosser where the user&#39;s fingers will act as a seesaw pivot or fulcrum. Hence, oscillation amplitudes generated by rotating eccentric weight  40  will be maximized in the vicinity of the floss span, for high flossing performance, while being minimized in the vicinity of the user&#39;s mentioned fingers. Since the flosser can be held at its lateral sides with modest finger pressure, the floss span will oscillate in an elliptical orbit having a vertical major axis. If the flosser is held tighter at its lateral sides, lateral motion will be reduced or resisted wherein the floss span oscillations will move in an approximately linear vertical path. Thus, the user can control the shape of the oscillation path of the floss span. 
     The flossing attachment is expected to be sold pre-loaded and pre-threaded with floss to be ready for use. The flossing action is so fast that the floss span polishes interdentally as it flosses. To slide floss span  47  between very tight abutting teeth, the user can press lateral sides  23  and  25  of the driver to increase floss span tension (as described above). On the other hand, if the floss span were to get caught on a user&#39;s dental appliance, the user can relieve pressure on sides  23  and  25  to slacken and dislodge the floss span. Then pressing button  30  removes the slack and normal operation can proceed. 
     With regard to maintenance, no floss-handling by the user will be needed for several flossings. After each flossing, the oral portion of the flosser (the portion that contacts the user&#39;s mouth) may be rinsed under a faucet and then left in a glass having about an inch of mouthwash for sanitizing the spooled used floss on the take-up spool. Alternatively, the user can skip sanitizing the spooled floss by pulling the used floss off the end of the take-up spool after each flossing. This can be done by first pulling down on floss span  47  wherein fresh floss will be drawn from supply spool  15  to allow slack for pulling off the used floss from spool  17 . The fresh portion of floss can then be attached to the take-up spool instantly by use of the floss gripper and the used floss can be cut off on the cutter. The flosser is then ready for the next use. The floss portion attached to the gripper will wind on the take-up spool by pressing switch button  30 . 
     Third Embodiment of a Flossing Attachment 
     FIG.  8   
     Removal of used floss and reset of fresh floss in the attachments described above is simple and quick. To provide another choice,  FIG. 8  shows a flossing attachment  12 C that requires no floss-handling at all. Flossing attachment  12 C is substantially the same as attachment  12  except for the following changes. The floss cutting feature is left out and a larger floss capacity take-up spool  57  includes floss-retaining disk flanges  59  and  61  at the ends, respectively, of its spool core. The greater floss storing capacity results mainly from the spool having a core with an ability to compel the floss to traverse along the length of the core as the floss is being wound. The core of spool  57  includes a pair of fixedly and coaxially connected augers  63  and  65 . Each being generally tapered or conical in shape and joined at its base or largest diameter with that of the other auger. Auger  63  has a right hand helical thread or flight and auger  65  has a left hand helical thread or flight so that the spool can be rotated such that each auger will push winding floss in a direction away from the other auger. 
     Augers  63  and  65  are plastic molded integrally with flanges  59  and  61  and a flexible and resilient driven shaft  69  as a one-piece unit. A first flossing tine  67  of attachment  12 C guides an incoming used floss strand  71  initially toward the middle of the core of spool  57  and approximately perpendicular to the core. When spool  57  is rotated in the mentioned direction, floss being wound on the spool core will be compelled to first traverse one auger toward its distal end. The slope of the accumulating floss coil and the natural tendency of the strand to return to the perpendicular position will urge the strand back to the middle of the core wherein the opposite auger takes over and the process is repeated thereon. 
     Eventually, both augers become covered with spooled floss and the floss will be broadly distributed on the spool core. The phantom lines around the core of spool  57  indicate a potential distribution of floss wound on the spool. 
     Except for the floss, flossing attachment  12 C can be molded entirely of plastic at low cost. After take-up spool  57  is filled with floss, attachment  12 C can then be discarded and replaced with another one pre-loaded and pre-threaded with floss. Each attachment can be used several times without any floss-handling by the user. 
     A version for single-use by dental hygienists may be devised having very small supply and take-up spools. Single-use attachments may be discarded and replaced after use on each patient. The benefit is the ability to simultaneously floss and polish surfaces between teeth at high speed, thereby saving time. 
     Forth Embodiment of a Flossing Attachment 
     FIG.  9   
     Shown in  FIG. 9  is flossing attachment  12 D which incorporates features of attachment  12 C of  FIG. 8 , but is intended for a large number of uses before being discarded. This maintenance-free embodiment requires no floss-handling by the user and can store a substantial amount of used floss hygienically before disposal. A take-up spool  57 A is structurally similar to spool  57  but is larger, especially in diameter. Spool  57 A has a core comprising a pair of fixedly and coaxially connected cone-shaped augers  63 A and  65 A. Auger  63 A has a right hand helical thread or flight and auger  65 A has a left hand helical thread or flight so that the spool can be rotated such that each auger will push winding floss in a direction away from the other auger. The augers  63 A and  65 A are arranged like augers  63  and  65  and are plastic molded integrally with the spool end flanges and with a driven shaft  37  as a one-piece unit. 
     Take-up spool  57 A is completely enclosed on all sides by a fluid-tight (liquid and gas tight) plastic capsule  35  integrally molded together with a bifurcated member. In production models, the capsule can be molded as two separate halves cemented together after enclosing the spool. Also enclosed in capsule  35  is a broad-spectrum high-viscosity antiseptic liquid  33  which is injected into the capsule through an aperture for fluid-tightly receiving a rubber plug made into a floss bearing  73  before the bearing is installed. Spool  57 A is submerged in the antiseptic liquid while being attached to a floss strand  71 A that passes into the capsule through bearing  73 . Strand  71 A is inserted through the center of bearing  73  by means of a sewing needle at the manufacturing plant before assembly of the attachment. During the insertion, the needle compresses the rubber around the needle until the needle and floss pass through bearing  73 . Then the rubber resiliently springs back to form a fluid-tight compression-seal around the floss resulting in the bearing being fluid-tight. This prevents antiseptic liquid and chemical odors from leaking out of the capsule. During winding, used floss is drawn through the floss bearing and is sanitized by the antiseptic liquid to prevent bacterial activity. 
     A posterior wall of capsule  35  defines an aperture surrounded by an O-ring seat for fluid-tightly supporting O-ring  84  encircling driven shaft  37 . A posterior portion of shaft  37  is fixedly and coaxially embedded in connecter  38  for being driven to rotate spool  57 A by driver  14 . As in the other attachments, floss supply spool  15  rotates independently of connecter  38  by slipping around the connecter as floss is drawn off spool  15 . 
     Floss from supply spool  15  is guided by floss guides similar to those described for attachment  12  and passes to the bifurcated member to form floss span  47 A. From there, the floss travels to capsule  35  via a channel  80 A which is similar to channel  80 . A proximal end portion of the bifurcated member defines a slot  92  where used floss exits from channel  80 A through a lateral side of the bifurcated member opposite the lateral side that guides fresh floss. From there the floss travels through bearing  73  where it enters capsule  35  and connects to spool  57 A as strand  71 A. 
     When flossing attachment  12 D is attached to driver  14  and driven to wind used floss and to oscillate the floss span during flossing, augers  63 A and  65 A compel the incoming used floss to traverse and distribute broadly on the core. In addition, the augers serve as impellers that circulate antiseptic liquid  33  to enhance the sanitizing effects. 
       FIG. 9  shows that most of the floss from spool  15  has been wound onto take-up spool  57 A. When the supply floss on spool  15  runs out, attachment  12 D can be discarded and replaced with a new one preloaded and pre-threaded with fresh floss. From the above description, it can be understood that attachment  12 D requires no maintenance other than rinsing the oral portion under a faucet after each use. 
     SCOPE AND CONCLUSION 
     While the description above is of specific embodiments along with some of their uses and applications, these should not be construed as limitations on their scope, but rather as practical examples. The embodiments shown can result in more than one choice of models especially because a model for personal use may differ from a model for professional use. 
     Other embodiments are also possible. The floss-cutting feature, for example, may alternatively be mounted flanking an upper portion of one of floss shields  60  or  62 . In that position, the floss-cutting feature would still be conveniently proximate to the take-up spool for cutting off used floss. On the other hand, a flossing attachment made for professional use will not require a floss cutter because the attachment will be discarded after being used on one patient. The power driver for use by a dental professionals, however, will be used for many patients and may therefore have a stainless steel housing or be adapted to an air-driven dental hand-piece. Dental tapes may substitute for floss and either one may carry one or more compounds that provide special scents, flavors, whitening, sanitizing, or polishing ability. 
     The power and amplitude of the oscillations generated by power drive  14  can be adjustable by the addition of a variable resister to the electric circuit. Alternatively, such amplitude adjustments can be achieved by making the eccentric weight changeable to eccentric weights of different mass. This can be done by threading a distal end portion of the posterior shaft to mate with a threaded aperture in each of a selection of different eccentric weights provided to buyers of the product. The thread should be spiraled to tighten in the opposite direction of the shaft rotation. Removal of detachable cap  11  provides user-access for making weight changes to suit individual users. 
     Color-coding or number-coding the flossing attachments can be a convenience for personalizing them in a household having more than one user of the automatic flosser. Thus, the driver can be shared without sharing flossing attachments. 
     An advantageous brushing attachment may be an added feature enabled by the rotational and high-speed oscillatory movements produced by the driver. Such a brushing attachment would have the advantages of being rotated and oscillated simultaneously. 
     Thus, the scope of the embodiments should be determined by the appended claims and their legal equivalents rather than by the examples given.

Technology Category: 1