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Publication numberUS3273439 A
Publication typeGrant
Publication dateSep 20, 1966
Filing dateAug 5, 1965
Priority dateAug 5, 1965
Publication numberUS 3273439 A, US 3273439A, US-A-3273439, US3273439 A, US3273439A
InventorsKeefe Chester P, Navilliat John C
Original AssigneeKeefe Chester P, Navilliat John C
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Device which accommodates removable frets on any fretted stringed instrument
US 3273439 A
Abstract  available in
Previous page
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Claims  available in
Description  (OCR text may contain errors)

p 20, 1966 c. P. KEEFE ETAL 3,


69 Bowen St., Providence, R.I. Filed Aug. 5, 1965, Ser. No. 477,570 4 Claims. (Cl. 84-314) This invention relates to a device which accommodates removable frets onany fretted stringed instrument, such for instance as a guitar. The purpose thereof being to facilitate the replacement of worm on damaged frets without damage caused to the stringed instrument in particular the fingerboard.

The fingerboard is that part of a fretted stringed instrument on which the frets are placed. It is usually made of wood and may or may not be of one piece with the neck of the instrument. Frets are those devices which are positioned on the fingerboard perpendicular to the long axis of the fingerboard with such proper spacing as to effect the desired pitch of the string or strings when fingered in the proper manner for playing the fretted stringed instrument. The frets are usually made of metal and usually inserted into slots cut into the wooden fingerboard for this purpose and held there by friction. When the frets become worn or damaged or otherwise need replacement, they must be pried out of the wooden fingerboard and a new fret inserted into the slot which previously held the fret being replaced. This is a task which requires much time and skill to perform. Also with each replacement of a fret in the same slot, the slot becomes less able to hold the fret with proper friction due to the resulting enlargement of the slot.

In general: The object of this invention is to provide a device or devices which facilitates the replacement of a fret or frets, quickly and easily on a fretted stringed instrument without causing damage to the fingerboard.

In particular: An object of this invention is to provide a device in the fingerboard of a fretted instrument which accommodates a removable fret thereby facilitating the changing of frets without damage to the fingerboard, said device being made of such suitable material as will resist wear such as plastic or metal.

Another object of this invention is to provide a fingerboard made of such suitable material as will resist wear such as plastic or metal to accommodate removable frets, thereby facilitating the changing of frets without damage to the fingerboard.

With these and other objects in view, the invention consists of certain novel features of construction as will be more fully described and particularly pointed out in the appended claims.

In the accompanying drawings:

FIG. 1 is a top plan view of a fragmental portion of a guitar showing the neck and strings thereon with the frets in the position which they assume along the neck;

FIG. 2 is an isometric view of a fragmental portion of the neck on a much larger scale illustrating a fret in position which is constructed in accordance with this invention;

FIG. 3 is an isometric view exploded to illustrate the fret and means provided on the fingerboard to hold the fret in position;

FIG. 4 is a sectional View on substantially line 4-4 of FIG. 2;

FIG. 5 is a sectional view on substantially line 5-5 of FIG. 2; and

FIGS. 6, 7, 8, 9, and 11 are views similar to FIGS. 4 and 5 of modified forms of the invention.

With reference to the drawings, 10 designates generally a guitar having a body portion 11 and a fingerboard 12 and over which there is arranged a plurality of strings 14 which are each suitably adjusted by post 15 and turning handles 16. The fingerboard 12, a portion of which is shown in FIG. 2, is formed in two parts, the lower portion usually called the neck being curved as at 17 with a fiat upper surface 18 upon which the upper portion 20 of the fingerboard is placed. Usually these two portions of the fingerboard are of wood with the upper portion of high quality, often being of rosewood.

In the upper portion 20 of the fingerboard, we have provided at the location where the frets are to be placed a groove 21 which extends laterally across the full width of the fingerboard and is perpendicular to the long axis of the fingerboard 12. In FIGS. 2, 3 and 4, plates 22 and 23 are set into recesses 24 and 25 along the edge of the groove 21 so as to overhang the groove and in elfect leave an undercut portion beneath them. These plates are spaced from each other along their adjacent straight edges so as to leave a channel or space between them. The plates may be held in position by screws 26 or they may be adhesively held in position, any means of holding such plates in position being within the contemplation of this invention.

The fret 30 is of a shape best seen in FIGS. 3 and 4 and comprises and upper frustro-pyramidal portion 31 or any other desired fret shape, and a retaining base portion 32 with a narrow neck 33 joining these two parts which will be of a length substantially the thickness of the plates 22 and 23 while the width of the neck 33 will be substantially the dimension of the space between the plates so that the fret 30 may be slid endwise into the groove 21 and will frictionally engage the plates 22 and 23 so as to hold the same in position. The fingerboard may be fiat or slightly arched as can best be seen in FIG. 5, and the fret which is normally straight will be slightly arched as it is forced into position so that its inherent tendency to straighten out will exert further friction on the plates and hold the fret in position. Frets of the correct length can be selected for insertion or may be cut to the correct length after installation and may be easily removed when worn and replaced.

In FIGS. 6 and 7 the fret, while in substantially the same shape as above referred to, is in this case inserted in a U-shaped channel member 35 having a bottom wall 36, side walls 37 each of which has an inturned edge 38 leaving a space 39 between them so that in effect there is provided a structure similar to the structure of FIGS. 2 to 5 above described except that the channel is provided of a one-piece structure.

In FIGS. 8 and 9 the groove is formed by an insert member 40 having a bottom wall 41, side walls 42 with outwardly extending flanges 43 to be set into recesses 44 along the sides of the groove which are formed to fit the member 40. In this case the fret 45 has the same sort of top portion as previously indicated which is now designated as 31 while a 'leg 46 is provided with a friction surface, such for instance as knurling, to frictionally engage the side walls of the insert member 40 to better retain it in position. In this case the fret may be inserted from the top but could be easily removed by laterally pushing it out of position.

In FIGS. 10 and 11 upper portion of the fingerboard 50 is formed of a material different than the lower portion and may be of a plastic material or metal or any better suited material than the Wood usually used in the fingerboard, and in this case grooves 51 of an inverted T-shape are formed directly in the fingerboard and receive the frets such as 30 which are of a shape complemental to the groove 51 to be held in position. It will of course be understood that varying shape grooves may be utilized in this fingerboard in accordance with the teachings above for the insertion of frets in position.

t We claim:

1. In a stringed instrument having an elongated fingerboard of one material with strings extending lengthwise I thereof, said fingerboard having portions of a different material providing grooves extending laterally of the extent of said strings and frets removably mounted and frictionally held in said grooves, said different material providing said grooves being of a character to provide greater frictional Wearing qualities than the material of the fingerboard to better withstand the wear of insertion and re moval of said frets.

2. In a stringed instrument as in claim 1 wherein said fingerboard is wood.

3. In a stringed instrument as in claim 1 wherein metal is used to provide at least a portion of the wall of the groove with which the fret engages.

4. In a stringed instrument as in claim 1 wherein said grooves provide undercut portions and said frets are of a complemental shape to be held in position by said grooves.

References Cited by the Examiner UNITED STATES PATENTS 7/1893 Stratton 843 14 8/1910 Finney 843 14 3/1926 Manby 84314 12/ 1949 Conkling et al 34414 5/1952 Maccaferri 84-314 12/1953 Maccaferri 84-314 9/1963 Webster 84-314 FOREIGN PATENTS 3/1937 I Great Britain.

RICHARD B. WILKINSON, Primary Examiner,

LEO SMILOW, Examiner.

20 L. J. CAPOZI, Assistant Examiner.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US501743 *Mar 28, 1893Jul 18, 1893 Fret for musical instruments
US967507 *Jul 6, 1909Aug 16, 1910Knute I FinneyFinger-board for musical instruments.
US1578744 *Aug 10, 1925Mar 30, 1926Jensen Manby Charles Evelyn CrFinger board of violins and like stringed instruments
US2492845 *Nov 6, 1947Dec 27, 1949Frederic E ConklingStringed musical instrument
US2597154 *May 15, 1950May 20, 1952Maccaferri MarioStringed musical instrument
US2664022 *Jan 5, 1952Dec 29, 1953French American Reeds Mfg Co INut for stringed musical instruments
US3103846 *Feb 14, 1962Sep 17, 1963Webster James DFinger board for stringed musical instruments
GB498022A * Title not available
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US4064779 *Jun 22, 1976Dec 27, 1977Petillo Phillip JFret
US4221151 *Jul 27, 1979Sep 9, 1980Barth Thomas GStringed musical instrument
US4311078 *Mar 30, 1981Jan 19, 1982Frank FalgaresBow playable guitar
US4633754 *Feb 19, 1986Jan 6, 1987Chapman Emmett HFret rod for stringed musical instruments
US4723469 *Mar 26, 1987Feb 9, 1988Vogt Walter JFret for the fingerboard of plucked stringed instruments
US4777858 *Apr 14, 1986Oct 18, 1988Petschulat David JAdjustable string contact system for a musical instrument
US4981064 *Dec 1, 1989Jan 1, 1991Vogt Walter JFingerboard for plucked and stringed instruments
US4987816 *Aug 28, 1989Jan 29, 1991The Sound Music Co., Inc.Fingerboard
US6369306 *Dec 18, 2000Apr 9, 2002Emmett H. ChapmanFret system in stringed musical instruments
US7507888 *Jan 11, 2008Mar 24, 2009Rivera Humberto Jason EFret and fingerboard for stringed instruments
US7692080 *Mar 7, 2008Apr 6, 2010Donna W. RushingFret wire with bending notches
U.S. Classification84/314.00R, 984/115
International ClassificationG10D3/06, G10D3/00
Cooperative ClassificationG10D3/06
European ClassificationG10D3/06