Abstract:
Ergonomic handset for precision manual tools comprising an elongated body and at least one working end comprising a tool-insertion opening at one of said body&#39;s ends and a gripping zone near said opening, said gripping zone comprising three finger-rests designed to form a triangular tapered profile. A saddle-like component may be attached to the handset at the middle thereof, to be worn around the ridge connecting the thumb and the forefinger.

Description:
CROSS-REFERENCE TO RELATED PATENT APPLICATIONS  
       [0001]     This patent application claims priority from and is related to U.S. Provisional Patent Applications Ser. Nos. 60/536,733 and 60/536,730, both filed on 16 Jan. 2004, these two U.S. Provisional Patent Applications incorporated by reference in their entirety herein. 
     
    
     FIELD OF THE INVENTION  
       [0002]     The present invention relates to the field of ergonomic manual tools, and more specifically to the gripping portions of small diameter tool handles.  
       BACKGROUND OF THE INVENTION  
       [0003]     Musculoskeletal Disorders (MSDs) are injuries and illnesses that affect muscles, nerves, tendons, ligaments and joints. Individuals suffering from MSDs may experience loss of gripping-strength, reduced range of motion, loss of muscle function and the ability to perform every-day tasks.  
         [0004]     Some of the common MSDs affecting the hands and wrists include: Carpal Tunnel Syndrome (CTS), Tendonitis, Lateral Apicondylitis, Synovitis and De Quervain&#39;s Tensosynovitis.  
         [0005]     CTS is the most common compression neuropathy of the upper extremity and is predominantly occupationally related, when the working environment requires repetitive hand-intensive tasks requiring a high level of pinch force and where the wrists are held in awkward positions for prolonged periods, such as in the dental hygiene profession, surgery, manual engraving, etc.  
         [0006]     CTS has been diagnosed in more than 10% of dental hygienists with Lip to 65% reporting pain in the hand and wrist. CTS is a nerve entrapment disorder that affects the median nerve as it passes through the region of the wrist known as the Carpal Tunnel. Symptoms of CTS include paresthesias, incoordination of the involved fingers, the relatively rapid onset of hand fatigue and, in severe cases, true hand weakness. Although symptom onset is generally insidious, it can be acute and precipitated by vigorous or prolonged hand use. Similarly, 9.2% of dentists have been diagnosed as having some type of repetitive motion disorder.  
         [0007]     U.S. Pat. Nos. 1,663,826; D249,062; 5,501,597; 6,471,514; 6,579,094; 6,390,818 and 6,305,937; and published U.S. applications: 2002/0110782; 2004/0038176; 2003/0022131 and 2004/0248063, provide various configuration of handles for dental tools.  
       SUMMARY OF THE INVENTION  
       [0008]     In one aspect, the present invention provides an ergonomic handset for precision manual tools comprising an elongated body; and at least one working end comprising a tool-insertion opening at one of said body&#39;s ends; and a gripping zone near said opening, the gripping zone comprising three finger-rests designed to form a triangular tapered profile.  
         [0009]     In another aspect of the present invention there is provided an ergonomic handset for precision manual tools comprising an elongated body; two working ends, each comprising a tool-insertion opening at one of said body&#39;s ends, respectively; and a gripping zone near the opening, the gripping zone comprising three finger-rests designed to form a triangular tapered profile; and a pivot axis between said two working ends.  
         [0010]     In yet another aspect of the present invention there is provided an ergonomic handset for precision manual tools comprising an elongated body; two working ends, each comprising a tool-insertion opening at one of said body&#39;s ends, respectively, and a saddle-like component attached to the handset at the middle thereof, to be worn around the ridge connecting the thumb and the forefinger.  
         [0011]     There has thus been outlined, rather broadly, the more important features of the invention in order that the detailed description thereof that follows may be better understood, and in order that the present contribution to the art may be better appreciated. There are, of course, additional features of the invention that will be described hereinafter and which will form the subject matter of the claims appended hereto.  
         [0012]     In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting.  
         [0013]     As such, those skilled in the art will appreciate that the conception, upon which this disclosure is based, may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention.  
         [0014]     These together with other objects of the invention, along with the various features of novelty which characterize the invention, are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and the specific objects attained by its uses, reference should be made to the accompanying drawings and descriptive matter in which there is illustrated exemplary embodiments of the invention.  
         [0015]     Other objects of the present invention will be evident to those of ordinary skill, particularly upon consideration of the following detailed description of exemplary embodiments.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0016]      FIG. 1  is a schematic drawing of a dental handset constructed according the principles of the present invention;  
         [0017]      FIG. 2  is a side-view of the handset according to a preferred embodiment of the present invention;  
         [0018]      FIG. 3  is a front-view of the handset according to a preferred embodiment of the present invention;  
         [0019]      FIG. 4  is a side-view depicting the handset of the present invention in operation;  
         [0020]      FIG. 5  is a front-view depicting the handset of the present invention in operation;  
         [0021]      FIG. 6  is a schematic drawing of another preferred embodiment of the handset of the present invention;  
         [0022]      FIG. 7  is a schematic drawing of yet another preferred embodiment of the handset of the present invention;  
         [0023]      FIGS. 8 and 9  depict the handset according to the embodiment of  FIG. 7  in operation; and  
         [0024]      FIG. 10  is a front-view of the saddle according to the embodiment of  FIG. 7 .  
     
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS  
       [0025]      FIG. 1  is a schematic drawing of a dental handset constructed according the principles of the present invention. The handset, generally denoted by numeral  10 , is designed to accommodate one or two tools, such as dental instruments  20 . Handset  10  comprises an ergonomically designed elongated body comprising gripping zones  30  on one or two ends thereof, and elevated portions  40  facing each of said gripping zones. Each elevated portion  40  is designed to accommodate the ridge between the thumb and the forefinger when the user is applying the opposite-side tool, as depicted in  FIG. 4 .  
         [0026]      FIG. 2  is a side-view of the handset  10 , viewed with only one inserted instrument, depicting the tapered shape of gripping zones  30 . The angle created between the two tangents t 1  and t 2  to the gripping zone  30 , prevents the hand from slipping backwards while force is being applied to the tool.  
         [0027]      FIG. 3  is a front-view of the handset  10 , depicting tool-insertion area  50  and the three finger-rests  45 , designed to accommodate the thumb, the forefinger and the index respectively, as depicted in  FIG. 5 . The triangular profile created by the three finger-rests  45  may be isosceles or equilateral, having concave or convex side, depending on the application.  
         [0028]     The four resting zones—finger rests  45  and elevated portion  40 —have the effect of dividing the stress between them when force is applied to the tool.  
         [0029]     In a preferred embodiment of the present invention, handset  10  may be constructed of a rigid plastic material, with finger rests  45  made of an elastomer having a high friction coefficient and a low Shore value. Alternatively, handset  10  maybe constructed entirely from rigid plastic material. In this case, friction-enhancing patterns such as bulges may be added to the finger rests  45  to avoid slippage of the fingers. The materials should be resistant to disinfecting products.  
         [0030]     Handset  10  may be rotationally asymmetry or symmetric, when rotated around its longitudinal axis or around its center.  
         [0031]     The tools to be held by the handset of the present invention, such as tooth-cleaning instruments, may be removably inserted into the one or two tool-insertion areas  50  in any manner known in the art, such as snapping, screwing, etc. Alternatively, non-replaceable instruments may be created by molding the handset of the present invention around the original one or two tools.  
         [0032]      FIG. 6  depicts another embodiment of the present invention, in which a pivot axis  55  connects the two opposite tips of handset  10 , to enable relative rotation between them. The relative rotation enables using the rotated tool at different angles, without the need to change the gripping position of the handset.  
         [0033]     In an additional embodiment of the present invention, as depicted in  FIG. 7 , a saddle-like component  60  is attached to handset  10  at the middle thereof. Saddle  60  is designed to be “worn” around the ridge of the human palm, connecting the thumb and the forefinger, as depicted in  FIGS. 8 and 9 . Saddle  60  comprises an outer bent plastic surface  65 , cushioned from within with soft, elastic material  70  ( FIG. 10 ) for easy adaptation to various hand shapes and sizes and having a suitable friction coefficient so as to attach to the hand without applying undue pressure. The cushioned part  70  is preferably produced of thermoplastic elastomers such as EVA, engulfing air-cushions or gel filling. The cushioned part  70  may alternatively be made entirely of gel, such as silicone, or of a sponge material such as for example foamed PE.  
         [0034]     The two opposite parts of the handset  10  are preferably not aligned horizontally, but rather define an angle between them, to create an optimal working angle, as may be seen in  FIGS. 8 and 9 .  
         [0035]     When working, the entire stresses on the hand are transferred to the saddle-mounted area, where they are “spread” over a larger and massive area with good support, to absorb the tension. This creates an effective counter-mass to facilitate the operation. Another advantage of the “saddle configuration is that it enables minimal relative movement between the hand, wrist and arm. The main muscles used are those of the arm, thus avoiding/minimizing movements and stresses on the muscles of the fingers and palm.  
         [0036]     In a preferred embodiment of the present invention, the “saddle”  60  is rotatably connected to the body of handset  10 , using any manner known in the art  80 , to allow a 360° rotation of the handset above the saddle. In a preferred embodiment the connection  80  is implemented by a spiral thread that enables elevation of the handset while rotating, to overcome obstacles such as the hand bones. The rotation is designed to facilitate tool change while maintaining the same hand position. Additionally, an intermediate stage may be defined, wherein the handset is rotated to a position in which the hand is free to perform other operations without the need to lay the tool down. A retaining arrangement, such as a snap, preferably holds the handset in the intermediate stage.  
         [0037]     In a preferred embodiment, the saddle may be detached from the handset, thus facilitating the choice of materials for the saddle, as e.g. disinfection may be done without the saddle.  
         [0038]     The saddle  60  of the present invention may also be used with “standard” tools, not having the tapered ends, to reduce the pressure applied to the fingers, as shown in  FIGS. 8 and 9 .  
         [0039]     It is appreciated that certain features of the invention, which are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the invention, which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable subcombination.  
         [0040]     Unless otherwise defined, all technical and scientific terms used herein have the same meanings as are commonly understood by one of ordinary skill in the art to which this invention belongs. Although methods similar or equivalent to those described herein can be used in the practice or testing of the present invention, suitable methods are described herein.  
         [0041]     It will be appreciated by persons skilled in the art that the present invention is not limited to what has been particularly shown and described hereinabove. Rather the scope of the present invention is defined by the appended claims and includes both combinations and subcombinations of the various features described hereinabove as well as variations and modifications thereof, which would occur to persons skilled in the art upon reading the foregoing description.