Siminoff Patents


By early 1970, Siminoff was heavily involved in the design and development of musical instruments and instrument manufacturing devices including carving machines to do the exact shaping of instrument necks, and mandolin top and back plates. By 1973, he had developed a multi-axis truss rod system to counteract the forces of string tension on musical instrument necks. For this design, he was awarded a U.S. Patent in 1974, and later licensed the patent to Gibson Incorporated.

Roger had several other musical designs in progress. These included the invention of a guitar tuning knob with a fold-out fast-wind crank for which he was granted a U.S. Patent and several foreign patents. The knob, dubbed the “CRANK,” has been licensed to Gibson and to Schaller (W. Germany), a world renowned manufacturer of tuning machines. A unique nut, with adjustable-action supports for each string, won Siminoff another U.S. Patent and subsequently was licensed to Dunlop Manufacturing. Then, his frustrations at the inconvenience of changing strings won him a few more patents; he developed two methods to change instruments strings without cutting, twisting, or knotting them. One design, a string with a special pin at its peghead end, was licensed to Gibson under the name “GRABBERS.”

In early 1984, Roger was granted another U.S. Patent, this one for an unusual modular guitar. It features interlocking parts that permit a musician to snap together an instrument to suit his or her tastes in much the same way a photographer might assemble camera bodies and lenses. Two years later, another patent followed, this one for a universal mounting system for tuning machines. Today, several other music-related designs are awaiting their turn for further development on the Siminoff workbench. Patent details follow:

roger_pat_trussTruss rod system: U.S. Patent 3,901,119, describes a vertabrae of links with a steel truss rod positioned off-center. When the rod is tightened, the linkage is forced to bend in the direction of the rod’s compressive force. In this system, there can be up-links, down-links, left- or right-links, or blanks (where no bending effort is exerted). Since the truss rod system is completely removable through the truss rod pocket (in the peghead), the links can be assembled in any sequence or order to correct a single axis or multiple axis defect.


roger_pat_guitarComponent Guitar: U.S. Patent 4,433,603 speaks of a guitar comprised of descrete interchangable components. With this design, a guitarist could assemble an instrument to suite his or her tastes of neck and body styles as well as interchanging pickups or electronic tone/volume control modules while playing. The system features a unique center section that is designed to hold the neck and body, as well as act as a central housing for all of the core wiring to accept pick-up and electronics modules. The center section’s unique neck support provides for access and playability of the entire fretboard. In this design, completed guitar parts could be sold as accessory items. Pickups and electronics snap-in.


roger_pat_crank Crankable tuning machine knob: This design, U.S. Patent 4,278,002, covers a fold-out rapid-wind knob to enable musicians to quickly and easily change strings. The crank handle is spring loaded and folds into the knob body when not in use. A simply pull opens the knob to allow for fast winding and unwinding of strings. With this crank knob, a musician no longer has to carry extra winder devices and strings can be wound on and off in a matter of seconds. The crank conforms to the shape of the knob when it is folded in place making it virtually invisible. The spring loaded feature prevents the knobs from rattling and causing unwanted noises.


roger_pat_nut Adustable nut: The adjustable nut, U.S. Patent 4,304,163, enables the musician to set the strings’ “action” high or low without the need to file the nut (and possibly file it too low rendering it unusable). Each string’s contact point is a small screw which threads into the nut body and can be stopped at quarter-turn adjusting points. The adjustable nut provides the most precise nut action available. Further, the metal (brass) design provides the additional advantage of being a desirable rigid non-damping string support (acoustically speaking).


roger_pat_stringString spool: To further simplify string installation, U.S. Patent 4,377,963 describes having the last few inches of string spooled onto a thimble so that the string could be instantly attached to the machine head and the necessary slack drawn out to install the string. (Stemming from this design, Siminoff developed strings with a pin on one end [licensed to Gibson as the “Grabbers”] enabling the pin to be placed into the hole of a traditional geared machine and instantly locked in place. With this string design and Siminoff’s crank design [above], an entire set of guitar strings could be changed in 1-1/2 minutes.)


roger_pat_machineGeared machine assembly: U.S. Patent 4,515,059, describes a unique tuning machine whose mounting bases are comprised of unique plates which emulate the shape and mounting holes of earlier machines. With this design, a guitarist changing from some early (no longer produced) machine to a new set of geared machines would be able to use the same mounting as the previous machines and not be left with unsightly holes or embossings in the paint where the previous machines used to be. It was intended that these machines would be sold as standard sets, and the various mounting plates to match the original machines would be available separately.


For more information, contact, or Siminoff Banjo & Mandolin Parts, Post Office Box 2992, Atascadero, CA 93423, USA

Click here to return to Siminoff Background