Abstract:
The present invention relates to a axial movement tuner that pulls an instrument string in any direction within hemispherical space where the string exits the tuner. The tuner is an adjusting thumbscrew that has a through borehole for string passage and a low friction bearing recessed within the thumbscrew knob, where instrument strings are installed by simply passing them through the thumbscrew bearing, on through the hole in the thumbscrew, and out through a horn shaped opening. Ball end string movement is stopped when the ball reaches the small diameter bearing hole. Tuning is accomplished by turning the thumbscrew causing axial movement of the string end ball while the bearing limits string rotation, and this axial movement of the string within the tuner is redirected by a smooth horn shaped opening to any direction within a hemispherical space defined by the tuner string exit opening.

Description:
FIELD OF THE INVENTION 
     The present invention relates to tuning of a string in a stringed musical instrument, particularly to a stringed instrument comprising of a hemispherical pull string tensioning mechanism. 
     BACKGROUND OF THE INVENTION 
     The invention of stringed instruments automatically required the invention of string tensioning devices for tuning the instrument. The conventional tuners used were made of wooden pegs, with a knob on one end. They also had a hole for string holding and fastening on the other end, that were inserted into a hole in a headstock at the end of the instrument neck. The string wrapped around the peg as the knob was turned and friction between the hole and the peg held it in place after tuning. Improvements followed with the invention of metal worm gear tuners that provided more precise adjustment and no peg slippage problems. Many other gearing configurations and enhancements followed worm gear tuners as discussed in U.S. Pat. No. 2,955,503A. 
     Most tuners are still mounted on a headstock at the end of the instrument neck, but more compact instruments have been developed that eliminated the headstock and moved the tuners to the other end of the strings somewhere on the body of the instrument. Conventional peg and worm gear tuners are difficult to fit onto the instrument body geometry. 
     Axial (or linear) pull tuners were invented to better fit the instrument body geometry as discussed in U.S. Pat. No. 5,103,708A. However, most available axial pull tuners are complex, some are large and limited in mounting options, and some have poor string clamping ability. 
     The peg and worm gear tuners are limited in pull direction to a single 360 degree plane that is perpendicular to the string attachment peg. Axial pull tuners in general are limited in pull direction to mostly in line with the tuner axis. 
     Thus, in the light of the above discussion there seems to be a need for an invention that provides an improvement over previous axial pull tuners and provides comparable performance with worm gear tuners. 
     OBJECT OF INVENTION 
     The principal object of the invention herein is to provide an improved hemispherical pull string tension mechanism that can pull the string in any direction on a 360 degree plane perpendicular to the tuner axis. 
     Another object of the present invention is to provide a device that can pull in any direction defined by a hemisphere between the 360 degree plane and the axial pull line. 
     Another object of present invention is to provide a device that is simple and compact having a wide range of installation options to accommodate instrument body geometry. 
     SUMMARY OF THE INVENTION 
     According to the present invention the device comprises of a receiving component with an internally threaded borehole. This component is mounted on the instrument body or headstock. The exit mouth of the borehole has a smooth horn shaped opening that allows the string to transition from the axial direction to any direction defined by the previously mentioned hemisphere. 
     The receiving component can be a single receiving component so there is a one-to-one relationship between it and the externally threaded rotating component. Or the receiving component can have multiple internally threaded boreholes with horn shaped exits, which can receive multiple externally threaded rotating components so there is a one-to-many relationship. 
     The device is further comprised of an externally threaded rotating component that screws into the instrument body mounted receiving component. This component has an axially centered smooth borehole for instrument string passage. It has a knob, also with a smooth borehole for string passage that is turned for tuning adjustments. 
     The device is further comprised of a low friction component attached to the end of the knob. This low friction component provides for attachment of the string that passes through both previously described components. The purpose of the low friction component is to allow the rotating component to turn for tension adjustment while the string rotation remains inconsequential. When used without ball end strings an auxiliary string terminator component is mated with the low friction component. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In the accompanying figures, similar reference numerals may refer to identical or functionally similar elements. These reference numerals are used in the detailed description to illustrate various embodiments and to explain various aspects and advantages of the present disclosure. 
         FIG. 1  illustrates the disassembled perspective view of the tuner in a one-to-one configuration according to the present invention; 
         FIG. 2  illustrates the cross-sectional view of the assembled tuner in a one-to-one configuration; 
         FIG. 3  illustrates the perspective view of a sample installation of the one-to-one configured tuners in an instrument body; 
         FIG. 4  illustrates the perspective view of a sample installation of the one-to-one configured tuners in an instrument headstock; 
         FIG. 5  illustrates the cross-sectional view of the assembled tuner in a one-to-many configuration; 
         FIG. 6  illustrates the perspective view of a sample installation of the one-to-many configured tuner on an instrument body; 
         FIG. 7  illustrates the perspective view of a sample installation of the one-to-many configured tuner in an instrument headstock; 
         FIG. 8  illustrates the perspective view of an auxiliary string terminator component for use with non-ball end strings according to one embodiment of the present invention; 
         FIG. 9  illustrates the perspective view of the auxiliary string terminator component being placed with respect to the low friction and rotating components according to one embodiment of the present invention; 
         FIG. 10  illustrates the perspective view of an auxiliary string terminator component for use with the non-ball end of the string according to another embodiment of the present invention; and 
         FIG. 11  illustrates the perspective view of the auxiliary string terminator component being placed with respect to the low friction and rotating components according to another embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     These and other features of the present invention will become readily apparent upon further review of the following specification and drawings. Other goals and advantages of the invention will be further appreciated and understood when considered in conjunction with the following description and accompanying drawings. While the following description may contain specific details describing particular embodiments of the invention, this should not be construed as limitations to the scope of the invention but rather as an exemplification of preferable embodiments. For each aspect of the invention, many variations are possible as suggested herein that are known to those of ordinary skill in the art. A variety of changes and modifications can be made within the scope of the invention without departing from the spirit thereof. 
     The following detailed description is intended to provide example implementations to one of ordinary skill in the art, and is not intended to limit the invention to the explicit disclosure. As one of ordinary skill in the art will understand, variations can be substituted that are within the scope of the invention as described. 
     The primary unique attributes of this invention are: the ability to tension an instrument string with a linear motion rotating component that includes a borehole for string passage and a low friction component to which the string is attached that allows the rotating component to rotate while the instrument string does not rotate. It further comprises a horn shaped exit in the receiving component that translates the rotating component axial pull into a pull in any direction within the hemisphere defined by the horn exit. 
     The device of the present invention can be configured in a one-to-one configuration with one rotating component and one receiving component per device, or the device can have a one-to-many configuration with multiple rotating components and one receiving component per device. While only one implementation of each configuration will be described, there are many other design variations that could be used to implement the basic principles of this invention. 
       FIG. 1  shows a disassembled perspective view and  FIG. 2  shows an assembled cross sectional drawing of a one-to-one implementation of the tuning device  100 . The receiving component  102  is rigidly attached to either the instrument headstock or body depending on the instrument configuration, and the rotating component  104  with its low friction component  106  engages the internally threaded receiving component to provide axial movement of the instrument string end  130  to tune the instrument. 
       FIG. 2  shows mechanism of the receiving component  102  being attached to the instrument body or headstock  132 . The smaller exterior diameter  112  of the receiving component  102  is inserted through a borehole in the instrument. The receiving component  102  is held rigidly in place by tightening a nut  108  with a washer  110  onto the threaded portion of the smaller exterior diameter  112  of the receiving component  102 . 
     Furthermore,  FIG. 2  also shows the rotating component  104  engaging with the receiving component  102 . The external threads  118  of the rotating component  104  screw into the matching internal threads  114  of the receiving component  102 . As the rotating component  104  turns, the threads  114  and  118  cause the rotating component  104  to move axially with respect to the receiving component  102 . 
     As shown in  FIG. 2  the low friction component  106  is inserted into a shallow borehole  126  in the rotating component  104 . The outer part  122  of the low friction component  106  is held permanently in place in the shallow borehole  126  by an interference fit or by an adhesive. 
       FIG. 1  illustrates a string  130  being installed with the present invention. The string  130  in this case is a ball end string. With the rotating component  104  fully engaged in the receiving component  102 , the open end of the string  130  is inserted through the bore of the inner part  124  of the low friction component  106 . The string continues on through a bore  128  in the rotating component  104  and exits through a horn shaped opening  116  in the receiving component  102 . The string  130  is then pulled fully through this tuning device until the ball end is stopped by the lesser diameter bore of the inner part  124  of the low friction component  106 . The open end of the string  130  is then fastened by some means not discussed here to the other end of the instrument  132 . Tuning of the string  130  is then accomplished by grasping the friction increasing surface  120  of the rotating component  104  and turning the rotating component  104 . This action causes the rotating component  104  to move axially to create the proper tension in the string  130 . Rotation of the string ball end is minimized by minimal rotation of the inner part  124  of the low friction component  106 . 
       FIG. 3  illustrates an example of several tuning devices being installed on the body of a headless guitar  132 . The receiving component  102  is mounted in a borehole through the wall of a recessed cavity in the guitar body  132 , and the rotating component  104  is screwed into the receiving component  102  from the outside of the guitar body  132 . The guitar strings  130  are inserted into the rotating component  104  and exit through the horn shaped opening  116  of the receiving component  102 . The strings proceed across the saddle  134  and then up the neck. The neck (not shown in the Figure) would have some type of string clamping device at the end of the neck where the headstock will normally be situated. 
     Further,  FIG. 4  also shows an example of several tuning devices being installed on the headstock of a guitar. The receiving component  102  is mounted in a borehole through the headstock of the guitar  132 , and the rotating component  104  is screwed into the receiving component  102  from underneath the guitar headstock  132 . The guitar strings  130  are inserted into the rotating component  104  from underneath the guitar headstock  132  and exit through the horn shaped opening  116  of the receiving component  102 . In this case, the guitar strings  130  follow the curvature of the horn shaped opening  116  of the receiving component  102  and proceed away from the tuning device in a direction that is perpendicular to the axis of the tuning device. The guitar strings  130  proceed across the nut  136  at the end of the guitar neck and down the neck. While not pictured, the guitar strings  130  would proceed down the neck and across the saddle to some type of string clamping device at the base of the guitar body  132 . 
       FIG. 5  shows an assembled cross sectional drawing of a one-to-many implementation of the tuning device with one receiving component  138  configured to accept multiple rotating components  104 . The receiving component  138  has multiple threaded boreholes  114  with corresponding horn shaped exits  116 . The position and orientation of these multiple threaded boreholes  114  and horn shaped exits  116  within the receiving component  138  can be varied to accommodate the geometry of the instrument with which it will be used. The receiving component  138  may contain one or more mounting boreholes  140  to accommodate instrument attachment with screws or bolts. Each threaded borehole  114  receives one rotating component  104 . The rotating components  104  in the one-to-many configuration are identical to those already described in the one-to-one configuration. 
       FIG. 6  shows an example of a one-to-many tuning device being installed on the body of a headless guitar  132 . The receiving component  138  is mounted on the body of the guitar  132  using screws  142  inserted into the mounting boreholes  140 , and the rotating components  130  are screwed into the receiving component  138 . The guitar strings  130  are inserted into the rotating components  104  and exit through the horn shaped openings  116  of the receiving component  138 . The strings proceed across the saddle  134  and then up the neck. The neck, which is not pictured, would have some type of string clamping device at the end of the neck where the headstock normally be situated. 
       FIG. 7  also shows an example of how a one-to-many tuning device might be installed on the headstock of a guitar  132 . The receiving component  138  is mounted on the headstock of a guitar  132  using screws  142  inserted into the mounting boreholes  140 , and the rotating components  104  are screwed into the receiving component  138 . The guitar strings  130  are inserted into the rotating components  104  and exit through the horn shaped openings  116  of the receiving component  138 . In this case, the guitar strings  130  follow the curvature of the horn shaped openings  116  of the receiving component  138  and proceed away from the tuning device in a direction that is almost perpendicular to the axis of the tuning device. The guitar strings  130  proceed across the nut  136  at the end of the guitar neck and down the neck. While not pictured, the guitar strings  130  would proceed down the neck and across the saddle to some type of string clamping device at the base of the guitar body  132 . 
       FIG. 8  shows a perspective drawing of the auxiliary string terminator component  144  according to one embodiment, which has a slotted end and a low friction component mating end  152 . The auxiliary string terminator component  144  is used to attach non-ball end strings  154 . It has a borehole  148  through which the instrument string  154  passes. A slot  146  on the slotted end allows the string  154  to be bent a right angle as it exits the borehole  148 , and then wound around a spool shaped groove  150  that wraps around the slotted end of the auxiliary string terminator  144 . The string  154  is wrapped under itself one or more times as it is wound around the spool shaped grove  150  one or more times to provide a friction grip of the string  154  on the auxiliary string terminator  144 . 
       FIG. 9  shows a disassembled perspective drawing of the relationship of the auxiliary string terminator  144  according to one embodiment, to the low friction component  106  and the rotating component  104 , as well as the non-ball end instrument string  154  routing through these components. It was previously explained that the low friction component  106  is mounted in the shallow borehole  126  in the rotating component  104 . The cylindrical low friction component mating end  152  of the auxiliary string terminator component  144  slips into the inner part  124  of the low friction component  106 . The non-ball end instrument string  154  passes through the center of the rotating component  104 , the low friction component  106 , and the auxiliary string terminator  144 , where it wraps around the spool shaped groove  150  of the auxiliary string terminator  144  as previously explained. 
       FIG. 10  shows a perspective drawing of the auxiliary string terminator collar  156 , which uses set screw and a low friction component mating end  152 . The auxiliary string terminator collar  156  is used to attach non-ball end strings  154 . It has a borehole  148  through which the instrument string  154  passes. A set screw  158  presses against the borehole  148  to provide a friction grip on the string  154 . The collar  156  rests on the rotating component  106  with spacing provided by flange  160 . 
       FIG. 11  shows a disassembled perspective drawing of the relationship of the auxiliary string termination collar  156  to the low friction component  106  and the rotating component  104 , as well as the non-ball end instrument string  154  routing through these components. It was previously explained that the low friction component  106  is mounted in the shallow borehole  126  in the rotating component  104 . The cylindrical low friction component mating end  152  of the auxiliary string terminator collar component  156  slips into the inner part  124  of the low friction component  106 . The non-ball end instrument string  154  passes through the center of the rotating component  104 , the low friction component  106 , and the auxiliary string terminator collar  156 , where it is held in place by friction provided by the set screw  158 . 
     Although an illustrative embodiment of the invention has been shown and described, it is to be understood that various modifications and substitutions may be made without departing from the novel spirit and scope of the present invention.