fig1 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 fig4 . fig2 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 . fig3 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 fig5 . the triangular profile created by the three finger - rests 45 may be isosceles or equilateral , having concave or convex side , depending on the application . 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 . 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 . handset 10 may be rotationally asymmetry or symmetric , when rotated around its longitudinal axis or around its center . 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 . fig6 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 . in an additional embodiment of the present invention , as depicted in fig7 , 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 fig8 and 9 . saddle 60 comprises an outer bent plastic surface 65 , cushioned from within with soft , elastic material 70 ( fig1 ) 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 . 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 fig8 and 9 . 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 . 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 . 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 . 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 fig8 and 9 . 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 . 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 . 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 .
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 .