Patent ID: 12260846

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT

Illustrative embodiments of the invention are described below. In the interest of clarity, not all features of an actual implementation are described in this specification. It will of course be appreciated that in the development of any such actual embodiment, numerous implementation-specific decisions must be made to achieve the developers' specific goals, such as compliance with system-related and business-related constraints, which will vary from one implementation to another. Moreover, it will be appreciated that such a development effort might be complex and time-consuming, but would nevertheless be a routine undertaking for those of ordinary skill in the art having the benefit of this disclosure. The tremolo systems for foldable fretted instruments and related methods disclosed herein boasts a variety of inventive features and components that warrant patent protection, both individually and in combination.

FIGS.1-3show an example of a foldable fretted instrument10having a body12and a neck14extending therefrom, according to some embodiments of the present disclosure. Although shown by way of example only as an electric guitar, it will be appreciated that aspects of the foldable fretted instrument10described herein may be used in any of a variety of other fretted instruments, including but not limited to acoustic guitars, ukuleles, banjos, bass guitars, etc. By way of example, the body12may include a host of standard components, such as (but not limited to) pick-ups16, a roller bridge18, a pick-up selector switch20, and tone and volume controls22. The body12may also include a string aperture24, through which strings pass from an actuator26disposed in a back recess of the body12(FIG.3). In some embodiments, the actuator may include a chassis52with a number of components for tightening and loosening the strings of the instrument10, including a string roller assembly54, as shown and described in detail in commonly owned and co-pending U.S. patent application Ser. No. 17/994,248, filed Nov. 25, 2022 and entitled “Foldable Stringed Instrument and Related Methods,” the entire contents of which are hereby incorporated by reference into this disclosure as if set forth fully herein.

In some embodiments, the back of the body12includes an electronic cover28and a switch cover30. The neck14may be coupled to the body12via a neck plate32secured with multiple fasteners (e.g., bolts) that threadedly engage a mid-neck hinge assembly34forming part of the neck14. With the operation of the actuator26, along with the mid-neck hinge assembly34, the instrument10is capable of folding in half for convenient transportation and/or storage. When a user wants to play again, the neck can be straightened out before operating the actuator26to tighten the strings and lock the neck14so the instrument10may be tuned and/or played.

According to aspects of the present disclosure, a first tremolo system11includes a tremolo cam13for selectively contacting and stretching the strings for temporary string attenuation, a tremolo bar15for a user to rotate from the top surface of the body12, a bar coupler17to couple the tremolo bar15to the tremolo cam13, and mounting knuckles19,21for rotatably mounting the tremolo cam13and bar coupler17to the actuator26. By way of example only, the tremolo cam13has an oblong (e.g., oval, elliptical, etc.) cross-sectional shape and is rotatably mounted to the actuator26via first mounting knuckle19and a second mounting knuckle21. The strings are located above the tremolo cam13as they pass from a floating tail piece (not shown) to a string roller assembly54. In some embodiments, the tremolo cam13is coupled to a tremolo bar15that extends through an aperture23from the top surface of the instrument body12. When the tremolo bar15is rotated by a user, the tremolo cam13will rotate to contact and stretch the strings to temporarily raise the string pitch. In some embodiments, a pick guard (not shown) may be used to cover the tremolo bar aperture23.

FIGS.4-5show the body12of the foldable fretted instrument10ofFIGS.1-3according to aspects of the present disclosure, including the tremolo bar aperture23dimensioned to pass the tremolo bar15from the upper surface of the instrument10. In some embodiments, the back of the body12includes an electronic cover28and a switch cover30, both of which are preferably coupled to the body12via a plurality of wood screws36or comparable fasteners. In some embodiments, strap buttons38may be provided for coupling to a guitar strap (not shown), which buttons are coupled to the body12via wood screws40or comparable fasteners. In some embodiments, an input jack plate42is also coupled to the body12, which may be used to electrically couple the guitar10to an amplifier or other output device (e.g., wireless headphones, etc.). In some embodiments, the body12may include a back recess44for housing the actuator26(within a chassis recess46) and for receiving the headstock of the neck14while in the folded state (within the headstock recess48). In addition to the string aperture24, in some embodiments the body12may include pick-up apertures50to receive the pick-ups16shown inFIGS.1-3.

In some embodiments, the body12may include a series of magnets for releasably securing various aspects of the guitar10while in the folded state. By way of example only, these magnets may include, but are not necessarily limited to, a headstock magnet41disposed within an upper landing43of the headstock recess48, as well as a pair of handle magnets45disposed in raised sections on the lower surface of the headstock recess48of the back recess44. For example, the headstock magnet41cooperates magnetically with ferrous (metal) aspects on the back surface of the headstock of the neck14while in the folded state, which ferrous aspects may include (but are not limited to) a magnet mounted to the back surface of the headstock and/or the tuners located on the back of the headstock. In some embodiments, the handle magnets45cooperate magnetically with ferrous (metal) aspects of the handle56when the handle56is positioned in the unlocked state, after it has been rotated from the locked state shown inFIG.3such that the handle56is located within the headstock recess48. This magnetic coupling will allow the handle56to be retained in the unlocked position while the instrument10is in the folded state according to aspects of the present disclosure. By way of example only, when it is desired to return the instrument10to the playing state, a user need only: a) straighten the neck; b) pull the handle56away from magnetic coupling with the handle magnets45; and c) rotate the handle56back into the locked state shown inFIG.3.

FIG.6shows the actuator assembly26of the foldable fretted instrument10ofFIGS.1-3with a first tremolo system11according to aspects of the present disclosure. By way of example only, the actuator assembly26includes a chassis52to be mounted within the chassis recess46, such as through the use of any suitable adhesives and/or mechanical coupling (e.g., screws, plates, etc.). The chassis52serves as a vehicle to carry or otherwise mount a variety of components, for example including (but not necessarily limited to) a string roller assembly54, a handle56, linkage58, a lock chassis60, and a cover62mounted on an upper surface of the lock chassis60. In some embodiments, a ramrod64having a pair of locking rods66is coupled to the lock chassis60. As will be described below, when the handle56is rotated from the position shown (locked) to a position approximately 180 degrees therefrom (unlocked), the lock chassis60will translate towards the string roller assembly54and thereby release a floating tail piece (not shown), which in turn will loosen the strings5of the instrument10such that the mid-neck hinge34(see, e.g.,FIG.3) can be used to fold the instrument10in half (for example). When a player wants to play the instrument10again, the neck14will be straightened and then the handle56rotated back into the position shown, which causes the lock chassis60to translate towards the headstock of the neck14and thereby push the floating tail piece (not shown) to tighten the strings so the instrument10can be tuned and/or played.

By way of example only,FIG.6. depicts an actuator assembly26having a first tremolo system11, shown before operation. In some embodiments, tremolo cam13is oblong in cross section. The tremolo bar coupler17rotates within the first mounting knuckle19and is rigidly connected to the tremolo cam13. The tremolo bar coupler17has a threaded post25(FIG.7) extending towards the body12, which is threadedly received within a threaded distal end27of the tremolo bar15. When the tremolo bar15is connected to the tremolo bar coupler17(e.g., via threaded engagement), then rotation of the tremolo bar15will cause the tremolo cam13to contact and bend the strings5for temporary pitch attenuation.

FIGS.7-8show the actuator assembly26of the foldable fretted instrument10ofFIGS.1-3with a first tremolo system11according to aspects of the present disclosure, before operation (FIG.7) and during operation (FIG.8) of the tremolo system11. By way of example only, the tremolo bar coupler17includes a threaded post25that extends through the tremolo bar aperture23formed in the body12, and a corresponding aperture formed in the chassis52of the actuator26, for threaded engagement with a threaded distal end27of the tremolo bar15. The tremolo cam13(with oblong cross section) is rotatably mounted between the first and second mounting knuckles19,21affixed to the actuator chassis52and rigidly coupled to the tremolo bar coupler17, which rotates within the first mounting knuckle19. Rotation of the tremolo bar15causes the tremolo cam13to bend the strings5for temporary pitch attenuation. By way of example, threaded distal end27of the tremolo bar15is a hollow cylinder with internal threads dimensioned to threadedly engage the threaded post25of the tremolo bar coupler17. The tremolo bar coupler17is rotatably mounted to the first mounting knuckle19. In some embodiments, the tremolo bar15may be longer than shown, in order to extend a sufficient distance from the surface of the body12of the instrument10.

FIGS.9-10show the actuator assembly26of the foldable fretted instrument10ofFIGS.1-3with a first tremolo system11according to aspects of the present disclosure, before operation (FIG.9) and during operation (FIG.10) of the tremolo system11. By way of example only, the first and second mounting knuckles19,21are mounted to the actuator chassis52via mounting screws29(or comparable fasteners). By way of example only, the first mounting knuckle19rotatably receives a first end of the tremolo cam13, and the second mounting knuckle21rotatably receives a second end of the tremolo cam13. The tremolo bar coupler17is rigidly connected to the tremolo cam13(e.g., via mounting screw31) and threadedly connected to the tremolo bar15via threaded engagement between the threaded post25and the distal end27of the tremolo bar15. The mounting knuckles19,21allow the tremolo cam13to rotate when the tremolo bar15is rotated towards the upper surface of the instrument10(best shown inFIG.8). More specifically, the tremolo bar coupler17drives rotation of the tremolo cam13under operation of the tremolo bar15. The tremolo cam13has an oblong cross section (cam) that contacts and attenuates strings5when the tremolo bar15rotated towards the upper surface of the instrument10.

By way of example only, as previously notedFIG.9illustrates the actuator assembly26prior to operation of the tremolo system11. In this instance, the mounting screw31securing the tremolo bar coupler17to the tremolo cam13is centered on the bar coupler17and the tremolo cam13has a major cross-sectional width w/(e.g., due to its oblong cross-sectional shape) that is oriented generally parallel to, and not in contact with, the strings5(see, e.g.,FIG.7for a side view of the tremolo cam13prior to operation). Additionally, in this initial pre-operation orientation, the tremolo cam13has a minor cross-sectional width w2positioned directly below the strings5and not in contact with the strings5(see, e.g.,FIG.11for a depiction of the tremolo cam13positioned below the default plane P1of the strings5).

By way of example only, as previously notedFIG.10illustrates the actuator assembly26during operation of the tremolo system11. In this instance, the mounting screw31securing the tremolo bar coupler17to the tremolo cam13is displaced from center on the bar coupler17(visually), depicting rotation of the bar coupler17. Moreover, the tremolo cam13has a minor cross-sectional width w2(e.g., due to its oblong cross-sectional shape) that is oriented generally parallel to, and not in contact with, the strings5, while the major cross-sectional width w1is rotated to be in contact with the strings5(see, e.g.,FIG.8for a side view of the tremolo cam13during operation andFIG.12for a depiction of the tremolo cam13rotated such that the major width dimension w1extends through the default plane P1of the strings5and contacts the strings5).

FIGS.11-12show the actuator assembly16of the foldable fretted instrument10ofFIGS.1-3with the first tremolo system11according to aspects of the present disclosure, before operation (FIG.11) and during operation (FIG.12) of the tremolo system11. By way of example only, the mounting knuckles19,21are mounted to a surface of the actuator chassis52. The first mounting knuckle19rotatably receives a first end of the tremolo cam13and allows to rotation of the tremolo cam13when the tremolo bar15is operated from front of the foldable fretted instrument10. The tremolo bar coupler17is rotatably mounted relative to the first mounting knuckle19and is rigidly coupled to the tremolo cam13(e.g., via set screw31). The tremolo bar coupler17includes a threaded post25, which by way of example is a cylindrical extension with a threaded exterior at the distal end. The threaded exterior of the post25enables a threaded engagement within the threaded distal end27of the tremolo bar15. When the tremolo bar15is rotated towards the surface of the instrument10(FIG.8), the rotational force is transferred to the threaded post25of the bar coupler17, which in turn drives rotation of the tremolo cam13to temporarily attenuate strings5. The tremolo cam13has an oblong cross section (cam) having a major width dimension w1that contacts and attenuates strings5when the tremolo bar15is rotated towards the upper surface of the body12. In some embodiments, the tremolo cam13may have a constant shape (as shown inFIG.12) to contact all the strings5at the same time. Alternatively, in some embodiments the tremolo cam13may have one or more regions that are raised or lowered (e.g., regions that have different major width dimensions) to contact a respective string in a predetermined manner. For example, the tremolo cam13may have raised areas to specifically attenuate the G-string and/or B-string of the six guitar strings in standard E-A-D-G-B-E tuning of a guitar.

FIGS.13A-14Bshow the tremolo cam13and tremolo bar coupler17of the first tremolo system11according to aspects of the present disclosure, before operation (FIGS.13A-13B) and during operation (FIGS.14A-14B) of the tremolo system11. By way of example only, the tremolo cam13includes an oblong base33with first and second cylindrical posts35,37, which are dimensioned to respectively extend into (and rotate within) the mounting knuckles19,21. The first cylindrical post35includes a screw recess39configured to threadedly receive at least a threaded portion of a mounting screw31therein to couple the tremolo cam13to the bar coupler17. The oblong base33of the tremolo cam13has an asymmetric cross-section, including a major width dimension w1and a minor width dimension w2, such that, when the tremolo system11is not in use, the oblong base33does not contact the strings5(FIG.11), and when the tremolo bar15is rotated during use, the oblong base33does contact and attenuate the strings5(FIG.12). By way of example only, the tremolo bar coupler17includes a cylindrical base63configured to rotate on the first mounting knuckle19. The threaded post25is integrally connected to the cylindrical base63and includes a threaded exterior to be threadedly received within the threaded distal end27of the tremolo bar15. The cylindrical base63of the bar coupler17includes a coupling channel65dimensioned to receive the first cylindrical post35of the tremolo cam13therethrough and a threaded aperture67dimensioned to threadedly receive a mounting screw31to couple the bar coupler17to the first cylindrical post35of the tremolo cam13, for example when first cylindrical post35is positioned within the coupling channel65with the screw recess39and threaded aperture67in alignment. When the tremolo bar15is engaged with the bar coupler17, then rotation of the tremolo bar15will cause the threaded post25of the bar coupler17and the oblong base33to rotate and thereby temporarily contact and attenuate the strings5.

FIGS.15-17are perspective, side, and bottom views of a foldable fretted instrument10with an example of a second tremolo system47according to aspects of the present disclosure. By way of example only, the second tremolo system47includes the string roller assembly54of the actuator26mounted between a pair of rocker assemblies49,51. Each rocker assembly49,51is capable of moving back and forth along the longitudinal axis of the actuator26. In some embodiments, an axle53is rotatably mounted to the actuator26and includes a threaded post (not shown) extending towards the top surface of the guitar body12for threaded engagement with the tremolo bar15. The axle53is connected to the rocker assemblies49,51via a pair of linkages55, which serve to push or pull the rocker assemblies49,51(and string roller assembly54) depending on the rotation of the axle53. Rotation of the tremolo bar15(extending through guitar body12) causes the rocker assemblies49,51(and string roller assembly54) to move back or forth to respectively raise or lower the string pitch.

FIGS.18-20show of the actuator assembly26of the foldable fretted instrument10ofFIGS.1-3with a second tremolo system47according to aspects of the present disclosure, before operation (FIG.18), during operation raising the string pitch (FIG.19), and during operation lowering the string pitch (FIG.20). In some embodiments, the rocker assemblies49,51are configured to move back (e.g., linearly in Direction A) and forth (e.g., linearly in Direction B) when the tremolo bar15is rotated toward and away from the upper surface of the body12. The tremolo bar15is coupled to the axle53via a threaded post (not shown), which extends from the axle53through the actuator chassis52. Linkages55rigidly connect the axle53to each rocker assembly49,51. The axle53rotates clockwise or counter-clockwise between the mounting blocks57,59when the tremolo bar15is rotated towards or away from the body12. When the axle53is rotated under direction of the tremolo bar15, the linkages55push or pull the rocker assemblies49,51either away (e.g., in Direction A) or towards (e.g., in Direction B) to respectively lower or raise string pitch. By way of example, the relative positioning of the string roller assembly54in the resting state is denoted by line S1inFIG.18.

As best shown inFIG.19, for example to increase the string pitch the rocker assemblies49,51are moved in Direction A when the tremolo bar15is rotated towards surface of the body12. When the tremolo bar15is rotated, the axle53rotates clockwise and causes the linkages55to push the rocker assemblies49,51(and string roller assembly54) in Direction A to temporarily raise the pitch of the strings. Releasing the tremolo bar15will allow the rocker assemblies49,51(and String Roller Assembly54) to return to the resting position and normal string pitch. By way of example, the relative positioning of the string roller assembly54in the raised pitch state is denoted by line S2inFIG.19.

As best shown inFIG.20, for example to lower the string pitch the rocker assemblies49,51are moved in Direction B when the tremolo bar15is rotated away from the surface of the body12. When the tremolo bar15is rotated, the axle53rotates counter-clockwise and causes the linkages55to pull the rocker assemblies49,51(and string roller assembly54) in Direction B to temporarily lower the pitch of the strings. Releasing the tremolo bar15will allow the rocker assemblies49,51(and string roller assembly54) to return to the resting position and normal string pitch. By way of example, the relative positioning of the string roller assembly54in the lowered pitch state is denoted by line S3inFIG.20.

FIGS.21-23show the actuator assembly26of the foldable fretted instrument10ofFIGS.1-3with the second tremolo system47according to aspects of the present disclosure, before operation (FIG.21), during operation raising the string pitch (FIG.22), and during operation lowering the string pitch (FIG.23). By way of example only, the axle53has a threaded post61which extends through the tremolo bar aperture23formed in the body12, and a corresponding aperture (not shown) formed in the chassis52of the actuator assembly26, for threaded engagement with the threaded distal end27of the tremolo bar15. When the tremolo bar15is rotated, the linkages55extending between the axle53and the rocker assemblies49,51will move back or forth to temporarily raise or lower the string pitch.

As best shown inFIG.22, for example to increase the string pitch the tremolo bar15is rotated downwards towards the body12. The linkages55extending between the axle53and the rocker assemblies49,51will push the rocker assemblies49,51(and the string roller assembly54) in Direction A to temporarily raise the string pitch. Releasing the tremolo bar15will allow the rocker assemblies49,51(and string roller assembly54) to return to the resting position and normal string pitch.

As best shown inFIG.23, for example to lower the string pitch the tremolo bar15is rotated upwards away the body12. Linkages55extending between the axle53and the rocker assemblies49,51will pull the rocker assemblies49,51(and the string roller assembly54) in Direction B to temporarily lower the string pitch. Releasing the tremolo bar15will allow the rocker assemblies49,51(and string roller assembly54) to return to the resting position and normal string pitch.

Any of the features or attributes of the above the above-described embodiments and variations can be used in combination with any of the other features and attributes of the above-described embodiments and variations as desired. From the foregoing disclosure and detailed description of certain preferred embodiments, it is also apparent that various modifications, additions, and other alternative embodiments are possible without departing from the true scope and spirit. The embodiments discussed were chosen and described to provide the best illustration of the principles of the present invention and its practical application to thereby enable one of ordinary skill in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. All such modifications and variations are within the scope of the present invention as determined by the appended claims when interpreted in accordance with the benefit to which they are fairly, legally, and equitably entitled.