Patent Publication Number: US-11037535-B2

Title: Low friction tuner

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Patent Application No. 62/792,439 filed Jan. 15, 2019, which is hereby incorporated by reference in its entirety. 
    
    
     FIELD 
     The present disclosure relates to tuners used on guitars and other stringed musical instruments. 
     BACKGROUND 
     Guitars and other stringed musical instruments use a tuner to adjust the tension of each string, thereby adjusting the pitch. On headless guitars, the tuner is mounted to the body of the instrument rather than the head. A common type of tuner used on headless guitars uses a knob fixed to a threaded rod, where the shoulder of the knob presses against a fixed housing and the threaded rod changes the position of a string carrier to adjust the tension on the string. In the prior art tuner, the string tension pulls the shoulder of the knob against the housing, creating a large amount of friction and making it difficult to turn the knob. Some designs in the prior art use a washer between the knob and the housing, which can reduce the amount of friction, but the knob still becomes difficult to turn when the string is under tension. 
     Therefore, a purpose of the present disclosure is to provide a low friction tuner that is easy to tune when the string is under tension. 
     BRIEF SUMMARY 
     The present disclosure includes a low friction tuner for a guitar or other stringed musical instrument. Relevant drawings are included with this disclosure. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
         FIG. 1  is a perspective view of the tuner shown with strings attached. 
         FIG. 2  is a rear view of the tuner. 
         FIG. 3  is a bottom view of the tuner. 
         FIG. 4  is a front view of the tuner. 
         FIG. 5  is a right-side view of the tuner where the left-side is a mirror image. 
         FIG. 6  is top view of the tuner. 
         FIG. 7  is a top sectioned view of the tuner shown where the tuner was sectioned parallel to the bottom through the centers of each tuning knob, tuning screw and point bearing assembly. 
         FIG. 8  is a side sectioned view of the tuner shown where the tuner was sectioned perpendicular to the bottom through the center of one tuning knob, tuning screw and point bearing assembly. 
     
    
    
     DETAILED DESCRIPTION 
     The present disclosure relates to a musical string instrument tuner that utilizes a point bearing to minimize rotational friction. 
     In conventional tuners for headless guitars, the tuning knob functions like the head of a screw and bears the full tension of the string. Due to the relatively large diameter of the knob (and washer if used), the tension of the string causes enough friction between the tuning knob as the body of the conventional tuner to make it difficult to turn the tuning knob. Tuners for stringed musical instruments must be placed precisely at the appropriate string spacing for that instrument, which often places the tuning knobs very close together and limits their overall diameter. Due to the limited amount of space between strings, larger tuning knobs to increase leverage cannot be used in most situations, making friction a significant consideration in tuners. 
     This disclosure greatly reduces the friction felt at the tuning knob by adjusting the geometry of the tuner so that the tip of the screw bears the tension of the string. 
     In  FIG. 1  is a perspective view of the tuner  10  shown with strings  11  attached. Tuning knobs  1  extends from the rear of the tuner  10  and string holders  5  extend from the front of the tuner  10 . The use of the terms front and rear are exemplary and only in reference to the drawings. Any directions used herein are for clarity only and are not intended to limit the scope of the disclosure. The string holders  5  can be configured, in some embodiments, to hold the ball end  8  of a string  11  in a slot  7 . In some embodiments, the string holders  5  comprise an elongate portion, where the distal end from the tuner body  20  further comprises the slot  7 . 
     In  FIG. 2  is a rear view of the tuner  10  showing the tuning knobs  1  extending from the body  20 . In  FIG. 3  is a bottom view of the tuner  10  showing the configuration of the body  20  relative to the tuning knobs  1 , the string holders  5  and the strings  11 .  FIGS. 4-6  are additional exterior views of the tuner  10  showing the configuration of the body  20  relative to the string holders  5  and strings  11  and the tuning knobs  1 . 
     In  FIG. 7  is a is a top sectioned view of the tuner  10  shown where the tuner  10  was sectioned parallel to the bottom through the centers of each tuning knob  1 , tuning screw  2  and point bearing assembly  9 . The tuning screw  2  is ground to a point  3  on one end with a tuning knob  1  fixed to the opposite end. The tuning screw  2  is inserted through a hole  4  in the back of the body  20  and threaded into a string holder  5 . The string holders  5  can have a long notch cut from the top so that it is U-shaped from the side view and can slide though a clearance notch  12  in the housing. On one end of the string holder  5  is a threaded portion  6  to accept the tuning screw  2 . A small slot  7  can be cut on the opposite end of the string holder  5  to accept the string  11  and retain the ball end  8 . The tip of the tuning screw  3  is held from sliding by a cup shaped bearing  9  that is mounted towards front of the body  20 . In some embodiments, the bearing  9  comprises external threads so the lateral position of the tuning screw  1  can be adjusted. 
     As the tuning knob  1  is turned, tension is applied to the string  11  and this tension force is transferred to the area between the tip of the tuning screw  3  and the bearing  9  rather than the area between the shoulder of the tuning knob  1  and the housing  20 . Due to the low rotational friction of a point bearing, the tuning knob  1  is relatively easy to turn compared to conventional tuners. 
     The present disclosure includes a tuner for use on a stringed musical instrument, which comprises a body comprising a bearing carrier fixed to an internal surface of the body; a tuning screw opening in the body opposite the bearing carrier; a slider opening in the body on the same side as the bearing carrier; a tuning screw with a first end and a second end, wherein the second end comprises a conical surface profile; wherein the tuning screw comprises a helical protrusion towards the second end; wherein the bearing carrier comprises a concave profile facing the tuning screw opening; wherein the tuning screw is slidably attached to the body through the tuning screw opening and the second end of the tuning screw slidably contacts the bearing carrier; a slider comprising a first end disposed on one side of the bearing carrier and a second end disposed on the opposite end of the bearing carrier; wherein the first end of the slider comprises a helical passageway configured to interface the helical protrusion of the tuning screw; and wherein the second end of the slider comprises a means for attaching a string. In some embodiments of the tuner, the slider further comprises a u-shaped profile in a direction. In some embodiments of the tuner, the slider comprises a u-shaped profile from a lateral direction relative to the body. In some embodiments of the tuner, the interface between the helical passageway and the helical protrusion are configured to cause movement of the slider relative to the body. In some embodiments of the tuner, the second end of the tuning screw further comprises a truncated conical profile. In some embodiments of the tuner, the slider is configured to freely slide through the slider opening in the body. In some embodiments of the tuner, the slider opening further comprises a location below the bearing carrier when the body is viewed in an upright direction. In some embodiments of the tuner, the means for attaching a string further comprises a slot configured to capture the ball end of a string. Some embodiments of the tuner further comprise a knob fixed to the tuning screw, wherein the knob is located outside of the body and does not contact the body. In some embodiments of the tuner, the bearing carrier further comprises a threaded outer surface and wherein the body comprises an opening with a correspondingly threaded opening configured to allow the threads of the bearing carrier to engage the threads of the body. In some embodiments of the tuner, the bearing carrier is further configured to allow adjustment in the direction from the bearing carrier to the tuning screw opening. 
     What has been described is a low friction tuner for use on a stringed musical instrument. In this disclosure, there is shown and described only the preferred embodiment of the invention, but, as aforementioned, it is to be understood that the invention is capable of use in various other combinations and environments and is capable of changes or modifications within the scope of the inventive concept as expressed herein.