US3722345A

US3722345A - Stringed musical instrument body construction

Info

Publication number: US3722345A
Application number: US00083310A
Authority: US
Inventors: R Dopera
Original assignee: Individual
Current assignee: Individual
Priority date: 1970-10-23
Filing date: 1970-10-23
Publication date: 1973-03-27
Anticipated expiration: 1990-03-27

Abstract

A structure for the soundbox of a stringed musical instrument is disclosed wherein the peripheral side wall is formed with channels at its bottom and top edges. The bottom and top of the body of the stringed instrument have flange portions on their peripheral edges which engage the channels on the side wall to form the soundbox. Mechanical and/or chemical means for strengthening the coupling between top and bottom flange portions of the body and the side wall channels is provided.

Description

United States Patent [1 1 Dopera Filed:

STRINGED MUSICAL INSTRUMENT BODY CONSTRUCTION Inventor: Rudolph Dope-2,1410 Gaylord St., Long Beach, Calif. 90813 Oct. 23, 1970 Appl. No.: 83,310

US. Cl. ..84/291, 84/267, 29/ 169.5 Int. Cl. ..Gl0d 3/00 Field of Search ..84/290, 291, 292, 296, 267;

29/ 169.5, DIG. 47

References Cited UNITED STATES PATENTS Springer ..84/292 Dopyera .....84/292 Maccaferri ..84/29l Dopera ..84/292 X p 51 Mar. 27, 1973 FOREIGN PATENTS OR APPLICATIONS 4,924 2/1932 Australia ..84/291 Primary Examiner-Richard B, Wilkinson Assistant Examiner.lohn F. Gonzales Attorney-Jones & Lockwood [57] ABSTRACT A structure for the soundbox of a stringed musical instrument is disclosed wherein the peripheral side wall is formed with channels at its bottom and top edges. The bottom and top of the body of the stringed instrument have flange portions on their peripheral edges which engage the channels on the side wall to form the soundbox. Mechanical and/or chemical means for strengthening the coupling between top and bottom flange portions of the body and the side wall channels is provided.

PATENTEDMARZ 7 I975 INVE/V r0? RUDOLPH DOPE RA A TTOR/VEYS STRINGED MUSICAL INSTRUMENT BODY CONSTRUCTION BACKGROUND OF THE INVENTION This invention relates to improved methods of designing and perfecting the soundbox or body of a stringed musical instrument and refers, in particular, to the fabrication of a guitar made of an extrudable material such as metal, thermoplastic resins, or the like.

Makers of stringed musical instruments usually are quite particular in selecting stock to make their instruments. Such instruments have heretofore been practically universally constructed of wood components suitably formed shaped and glued together. Despite careful workmanship, stresses and strains develop in various parts of these instruments as a result of changes in weather conditions and the like, which cause warping and shape distortions. Consequently, these conditions affect the tone and quality of these instruments.

Efforts have been made to alleviate these problems by using metals, e.g., steel, aluminum and the like to construct such instruments, and for many years such stringed instruments have been made by duplicating in metal the construction techniques used for wood. Thus, complicated welding and soldering procedures have developed which make the manufacture of such instruments difficult, resulting in high costs. Although aluminum is at present a preferred material for these instruments, the difficulties involved in welding this metal has effectively precluded its use.

SUMMARY OF THE INVENTION- It is an object of this invention to provide a new and useful method and apparatus for constructing the soundbox or body of a stringed musical instrument which is simple and inexpensive.

Another object of this invention is to provide a side wall construction for a soundbox which facilitates construction of the instrument, while at the same time providing a novel and decorative appearance.

More particularly, the object of this invention is'to provide a new method and apparatus to construct the body of a guitar which is simple in operation and does not require any elaborate pre-shaping or welding to join the top and bottom portions of the guitar to the peripheral side portion thereof.

According to this invention, a peripheral side piece for the soundbox of a stringed instrument is fabricated, as by extrusion, from a suitable material, which may be a thermoplastic resin of selected type, a metal, preferably aluminum, or like material so that it has channels at its top and bottom ends. The side piece is then formed to the desired soundbox shape so that top and bottom portions of the body of the instrument, which are fabricated to have appropriate shapes and include flanges, will fit the channels of the peripheral side piece. The structure so obtained can be further strengthened by chemical bonding using an epoxy or other suitable adhesive, and/or by mechanical means, such as rivets or the like. The side piece is preferably formed with a plurality of grooves extending parallel to the upper and lower edges of the side wall, these grooves serving to strengthen the wall and to provide receptacles for suitable decorative material.

2 BRIEF DESCRIPTION OF THE DRAWINGS The foregoing and additional objects, features and advantages of the invention will be apparent from the following description and from the claims appended thereto, taken in conjunction with the accompanying drawings, in which:

FIG. 1 is an exploded view of a soundbox for a stringed musical. instrument made according to the teachings of the present invention, but with the strings and complemental parts omitted for clarity;

FIG. 2 is a cross-section of the side wall of FIG. 1 taken along line 2-2;

FIG. 3 is a cross-section similar to that of FIG. 2, but showing another embodiment of the peripheral side wall of the soundbox;

DESCRIPTION OF PREFERRED EMBODIMENTS Referring now to the drawings, where like numerals show the same parts in each figure, and first particularly to FIG. 1, the peripheral side wall of a musical instrument embodying the present invention .is indicated generally at 8..For purposes of this description, the instrument will be described as a guitar, but it will be understood that other stringed instruments can be similarly constructed. The peripheral side wall 8 is formed from an elongated sheet 10 of a metal, preferably aluminum, a plastic material, or the like, extruded in the desired cross-sectional configuration. The extrusion has a channel 12 at the top edge 14 thereof, as may be seen in FIG. 2, and a similar channel 16 at 7 the bottom edge 18. Channel 12 is formed by two walls,

as may be seen in FIG. 2, an outer wall 20 and an inner wall 22. The sheet from which the side wall is formed is preferably of uniform thickness, being extruded through a die in known manner to form the desired cross-sectional shape to be given to the side wall. The open ends of the elongatedsheet so formed are then brought together while shaping the sheet against a suitable forming block (not shown) to form the desired guitar body'outline, as illustrated in FIG. 1, and the ends of the sheet are secured together at 24 as by welding or some other suitable means. The forming block will preferably be of steel, grooved and shaped to the exact size and contour of theinstrument being formed. As further illustrated in FIG. 2, the cross-sectional shape of the peripheral side wall 8 in one embodiment may be of uniform thickness, providing a flat, smooth outer surface. It will also be seen in FIG. 2 that thechannel 16 at the bottom edge 18 of the side wall is formed by two parallel, spaced walls, an outer wall 26 and an inner wall 28. As illustrated, the inner walls of both the upper and lower channels are formed on inwardly ofiset

shoulders

30 and 32, whereby the outer walls remain flush with the outer surface of the wall, and both channels extend at a uniform depth around the corresponding edge of wall 8.

FIG. 3 shows a cross-section of a peripheral side wall similar to that of FIG. 2, but indicating another embodiment of the invention. The modified side wall 36 includes a top edge channel 12 formed by an outer wall and an inner wall 22 and a bottom edge channel 16 formed by an outer wall 26 and an inner wall 28. The peripheral side wall 36 in this embodiment is extruded with a different cross-sectional shape, so that the exterior surface of the wall is provided with a plurality of grooves 44 and ridges 46 extending the length of the sheet from which the guitar body walls are formed. The interior surface of the wall is thus formed with cor responding ribs 47 which serve to reinforce the wall. The grooves are adapted to receive a decorative material, such as the decorative inlay strips described and claimed in copending application Ser. No. 3,107, filed .Ian. 15, 1970, and entitled Decorative Trim,

which is a continuation-in-part of application Ser. No.

776,919, filed Nov. 19, 1968, now abandoned. These decorative inlay strips may take many forms, as set forth in detail in the said copending application, but in one form may comprise an extruded conduit of transparent or translucent damage-resistant material. The conduit preferably will have at least one inner bore of any suitable cross-sectional shape, and is adapted to receive a decorative material such as twisted fibers, metallic cords, ribbons, braids, or other materials of selected colors or color combinations. In the illustration of FIG. 3, the depth of grooves 44 is sufficient to hold the decorative inserts so that their upper surfaces will be flush with the outer wall surface; further, the grooves are slightly dovetailed so as to firmly hold the decorative inserts in place.

The grooves 44 and ridges 46 are formed in the sheet from which the guitar body is to be formed, the sheet being extruded from a suitably-shaped die, and the decorative inserts are placed in the grooves by sliding them in from one end of the sheet. If desired, the inserts may be glued in place, or otherwise fastened; however, the dovetail arrangement is generally sufi'rcient to hold the inserts. Thereafter, the extruded sheet may be shaped around a suitable forming block to form the peripheral side wall contours shown in FIG. 1. It will be apparent that in so forming the sheet, care must be taken to reduce the amount of distortion of the grooves around the curved areas of the side wall, but the use of a grooved forming block facilitates this. The shaping of the side wall also shapes the decorative material, with the bends in the sheet serving to close the dovetailed walls of the grooves against the inserts to hold them tightly in place.

Referring again to FIG. 1, there is shown in perspective view the top portion 48 of the guitar body which has a depending flange 51 adapted to mate with the channel formed in the upper edge of the side wall 8 in forming the guitar soundbox. The top portion is generally flat, although other configurations, including various curvatures, are also possible, and is provided, in conventional manner, with a sound opening 50. Also shown in the exploded view of FIG. 1 is a perspective view of the bottom portion 52 of the guitar body, this portion including an upstanding peripheral flange 53 adapted to mate with the channel formed in the bottom edge 18 of the peripheral side wall 8 to complete formation of the soundbox. Again, the bottom portion may be flat or curved in known manner to provide the desired instrument shape. As with the side wall, the top and bottom portions of the guitar body can be made of a metallic material, preferably aluminum, a plastic material, or the like, and generally will be stamped out of a sheet of the selected material. The peripheral side wall 8, top portion 48, and the bottom portion 52 form the body, or soundbox, when they are joined together.

FIG. 4 is a partial cross-section of the top portion 48 taken along line 4-4 of FIG. -1 wherein numeral 54 indicates the upper surface,or face, of the top portion and numeral 51 shows the depending flange which is shaped to fit in the upper channel 12 of the peripheral side wall 8. The thickness of the top portion is shown to be generally uniform, although variations of thickness are also possible. A small lip 60 of the top portion 48 extends beyond the flange 51 by a distance equal to the thickness of the outer wall 20 of the channel, so that the top portion 48 will completely cover the side wall when the soundbox has been assembled. The bottom portion 52 has a structure similar to that of the top portion and is thus not shown in detail.

FIG. 5 is a vertical cross-section of an assembled, modified guitar body soundbox, having a top portion 64, a bottom portion 66, and a peripheral side wall 68, the three elements being in engagement with one another to form the guitar body. The top portion 64 and the bottom portion 66 are, in this embodiment, formed with a downtumed edge 70 and an upturned edge 72, respectively, the edges providing flanges to engage the

channels

12 and 16 in the top and bottom edges of the peripheral side wall. As shown, the

flanges

70 and 72 so formed do not have an outwardly extending lip to cover the thickness of the outer wall of the channels on the peripheral side wall. It will be apparent, however, that the flange arrangement of FIG. 4 can be used with the side wall 68, if desired.

The peripheral side wall 68 is provided with a plurality of parallel depressions 74 extending along its periphery, which are adapted to receive a decorative inlay strip material of the type described above. These depressions are formed, as before, during extrusion of the side wall, but in this embodiment the decorative strips may be placed either before or after the soundbox has been formed. The depressions 74 may be generally rectangular in cross-section, or may be of other suitable shape. The interior surface of wall 68 is formed with a plurality of ribs 75 corresponding to the depressions 74, these ribs serving to reinforce and strengthen the side wall.

To assemble the soundbox of any of the disclosed embodiments, the flanges of the top and bottom portions are fitted into the respective top edge and bottom edge channels of the side wall portion. Although the size of the channels is such that the flanges are held tightly in place by friction, it has been found that because the materials used in making the soundbox, a tightly fitting joint will not hold; therefore, the joint should be further strengthened by using an epoxy glue in the channels before fitting the flanges therein. The

similar fasteners 76, 78, 80, and 82 spaced around the periphery of the soundbox, the rivets passing through both walls of the channel and throughtheflange, as illustrated.

Thus, there has been described and illustrated a new and improved structure for a guitar body, wherein the side wall is formed from an extrusion having a unique configuration which facilitates construction of the guitar, improves its strength, and provides a novel and decorative appearance. The use of channels on the top and bottom edges of the side wall together with flanged top and bottom covers permits quick assembly of the guitar, for the flanges assure proper fit and alignment of parts. Further, this construction permits the use of rivets, epoxy resin glue, welds or other fasteners which assure a strong and durable soundbox that will withstand long and hard use. The form of the side walls is such as to accommodate the use of extrusion processes in the manufacture of the guitar, thus minimizing the cost of making the guitar, and permitting the use of the grooved structures illustrated in the various embodiments of the invention. These grooves serve not only to receive decorative inlay materials, as discussed above, to provide a new and striking appearance in the completed guitar, but the shape of the grooves is also such as to provide added strength and rigidity to the guitar, for in making exterior grooves, there are formed corresponding interior ribs. The extrusion process facilitates making the instrument of not only metals such as aluminum, but thermoplastic resins of various types.

Although the invention has been shown and described in terms of specific embodiments thereof, it will be understood that various changes may be made from the construction disclosed without deviating from the spirit and scope of the invention as set forthin the following claims.

I claim: a

1. In a soundbox for a stringed musical instrument having a bottom portion having a first flange along its periphery and facing generally vertically upward; a top portion of shape matching the bottom portion, and having a second flange along its periphery facing generally vertically downward; a peripheral side wall of shape matching the bottom and top portions and having two edges, an upper edge and a lower edge, the lower edge of the side wall having a first channel adapted to receive said first flange to form a first joint and the upper edge of the side wall having a second channel adapted to receive said second flange to form a second joint, whereby the soundbox is formed; the improvement comprising:

a plurality of parallel, longitudinally extending decorative material receiving grooves on the outer surface and extending the length of said peripheral side wall, and corresponding parallel, longitudinally extending ribs on the peripheral inner surface of said side wall, said ribs serving to reinforce 5 said side wall.

2. The soundbox of claim 1, wherein said grooves are dovetailed in order to receive and hold decorative inlay strips correspondingly dovetailed.

3. A method of making a soundbox for a stringed 10 musical instrument which comprises the steps of:

a. extruding an elongated sheet having an upper and a lower edge and first and second ends, while for'min a first channel in said upper edge, a secon channel in said lower edge, a plurality of grooves in one surface of said sheet extending the lengthof said sheet, and a plurality of ribs in the other surface of said sheet extending the length of said sheet, and said grooves and ribs being parallel to said upper and lower edges and said grooves being adapted to receive decorative inlay strips;

b. locating decorative inlay strips in said grooves;

c. wrapping said sheet around a forming block, said block being shaped to the desired'contour of a sidewall for said soundbox and having grooves on its peripheral wall surface corresponding to the ribs formed in the inner surface of said sheet, the ribs on said sheet fitting into the grooves on said block as said sheet is wrapped around said block,

d. securing the two ends of the sheet material together to retain the shape of said side wall;

. e. forming a top portion of said soundbox, said top portion being formed with a flange extending generally vertically downward;

f. forming a bottom portion for said soundbox, said bottom portion being formed with a flange extend ing generally vertically upward;

g. fitting the downwardly extending flange of the top portion into the first channel of the peripheral side wall to form a first joint;

h. Fitting the upwardly extending flange on the bottom portion into the second channel of the peripheral side wall to form a second joint, thereby completing the assembly of said soundbox.

4. The method of claim 3, which further comprises second joints to secure said top and bottom portions to placing rivets at spaced locations through said first and

Claims

1. In a soundbox for a stringed musical instrument having a bottom portion having a first flange along its periphery and facing generally vertically upward; a top portion of shape matching the bottom portion, and having a second flange along its periphery facing generally vertically downward; a peripheral side wall of shape matching the bottom and top portions and having two edges, an upper edge and a lower edge, the lower edge of the side wall having a first channel adapted to receive said first flange to form a first joint and the upper edge of the side wall having a second channel adapted to receive said second flange to form a second joint, whereby the soundbox is formed; the improvement comprising: a plurality of parallel, longitudinally extending decorative material receiving grooves on the outer surface and extending the length of said peripheral side wall, and corresponding parallel, longitudinally extending ribs on the peripheral inner surface of said side wall, said ribs serving to reinforce said side wall.

3. A method of making a soundbox for a stringed musical instrument which comprises the steps of: a. extruding an elongated sheet having an upper and a lower edge and first and second ends, while forming a first channel in said upper edge, a second channel in said lower edge, a plurality of grooves in one surface of said sheet extending the length of said sheet, and a plurality of ribs in the other surface of said sheet extending the length of said sheet, and said grooves and ribs being parallel to said upper and lower edges and said grooves being adapted to receive decorative inlay strips; b. locating decorative inlay strips in said grooves; c. wrapping said sheet around a forming block, said block being shaped to the desired contour of a sidewall for said soundbox and having grooves on its peripheral wall surface corresponding to the ribs formed in the inner surface of said sheet, the ribs on said sheet fitting into the grooves on said block as said sheet is wrapped around said block, d. securing the two ends of the sheet material together to retain the shape of said side wall; e. forming a top portion of said soundbox, said top portion being formed with a flange extending generally vertically downward; f. forming a bottom portion for said soundbox, said bottom portion being formed with a flange extending generally vertically upward; g. fitting the downwardly extending flange of the top portion into the first channel of the peripheral side wall to form a first joint; h. Fitting the upwardly extending flange on the bottom portion into the second channel of the peripheral side wall to form a second joint, thereby completing the assembly of said soundbox.

4. The method of claim 3, which further comprises placing rivets at spaced locations through said first and second joints to secure said top and bottom portions to said peripheral side wall.

5. The method of claim 4, which further comprises applying an epoxy resin to the first and second flanges and to the first and second channels before fitting the flanges into the respective channels to form the first and second joints.