US1364466A - Banjo - Google Patents

Description

F. F. VAN EPS.

BANJO.

APPLICATION FILED JAN. 28, 1920.

Patented Jan. 4, 1921.

18 .Zkvezz for J llorneua m'irzease's UNITED FRED F. VAN EPS, OF ILAINFIELD, NEW JERSEY.

BANJO.

Application filed January 28, 1920.

To all whom it may concern:

Be it known that I, FRED F. VAN Ers, a citizen of the United States, and a resident of Plainfield, in the county of Union and State of New Jersey, have invented a certain new and useful Improvement in Banjos, of which the following is a specification.

M invention relates to banjos, and more particularly to an instrument employed on the stage or in phonograph recording and has for its object the production of a device by means of which sound waves set up by vibrations at the rear of the membrane or head will be reflected out through the head and in the direction of the audience or of the talking machine recorder.

A further object is the provision of means whereby the sound waves set up at the rear of the head may be reflected toward any desired point within the limits of the body of the instrument.

Further objects are to improve the tone generally and to provide means for sustaining the tone of the instrument.

These and further objects will more fully appear in the following specification and accompanying drawings considered together or separately.

I have illustrated one embodiment of my invention in the accompanying drawings in which like parts of all of the several figures are designated by similar characters of reference, and in which- Figure 1, is a plan View of a banjo embodying my invention; h

Fig. 2 is a longitudinal section of the same partly in side elevation.

Fig. 3 is a detail section of a modified form of reflector, and I v Fig. 4 is a similar view of a further modification. a.

In carrying out the invention provide a banjo having a body comprising a hoop 1 of any suitable construction, over one end of which is stretched a head or membrane 2, in any well-known manner. I have illustrated the head as secured to the hoop by means of a ring 3 which is held in position by means of hooks 4 carried b ythe hoop and engaging the ring. The hooks are of the usual construction having threaded shanks I Specification of Letters Patent.

Patented Jan. 4:, 1921.

Serial No. 354,565.

and carrying nuts which bear against brackets carried on the outer periphery of the hoop whereby the tension of the head may be varied.

To one side of the hoop 1 is secured a neck or finger piece 5, and at the diametrically opposite side of the hoop is a tail piece 6. The usual strings 7 are attached to the tail piece and passed over the head 2, being spaced therefrom by a bridge 8, and are secured to pegs or keys (not shown) at the end of the neck 5.

Within the hoop is located a longitudinal brace 9 to which is secured one end of a turnbuckle 10 the opposite end of which is secured to the base of the neck 5. Carried within the hoop l on brackets 12 is an annulus 13. The diameter of the annulus is somewhat less than that of the hoop, thus forming an annular space between the annulus and the hoop. The plane of one end of the annulus is above that of that end of the hoop over which the head is stretched, whereby that part of the head lying between the annulus and the hoop will be prevented from vibrating in unison with the strings when the latter are struck. The effective vibratory area of the head will be reduced by the annulus 13, and the volume of tone of the instrument will be considerably increased. H

The shape of the annulus is not that of the hoop 1. One side 14 of the annulus isflattened as shown, and this flattened or straightened portion is disposed between the bridge and tail piece as shown, whereby the vibrating portion of that part of the head on which the bridge restsand which is subjected to the greatest amplitude of vibration, is further reduced.

At a point between the bridge 8 and the base of the neck of the figure board 5 and beneath the strings 7, an opening 15 is formed in the head for the purpose of permitting the escape of sound waves set up at the back or reverse side of the head.

Carried by the annulus 13 is a concavoconvex reflector 16 01" resonant material and having its concave side opposed to the head 2, whereby sound waves set up by the back of the head will be reflected through the opening 15. The reflector 16 is of the same peripheral shape as the annulus 13 and the point or" the reflector farthest removed from the head is considerably less than the depth of the hoop 1, whereby the distance of travel of the sound waves between the vibrating head and the reflector will be short.

The fact that the reflector is carried by, and is of the same size and shape as the annulus 13, will prevent the escape of sound waves from that portion of the device nearest the opening 15, except through the said opening, and none of such sound waves can be reflected against the inner side 01": the hoop or against that portion of the head lying between the annulus and the hoop, and which by reason of the annulus is rendered non-vibratory.

By my invention the space behind the vi bratory active portion of the head is very greatly reduced without changing the appearance of the instrument, the distance traveled by sound waves set up on the reverse side of the head will be short, and such sound waves will be projected through the head in the same volume and with the same intensity as those waves set up on the front of the head. The concave shape of the reflector will cause all of the sound waves reaching it to be directed toward and through the opening in the head.

Instead of making the reflector in the form of the segment of the sphere as shown in Fig. 2, the shape illustrated in Fig. 3 may be employed. In this embodiment of the invention the reflector 17 is parabolic, whereby the sound waves set up at the point of greatest vibration of the head, that is directly below the bridge 8, will be reflected directly through the opening in the head. The reflector surface may be so shaped that sound waves from all parts of it will be directed to the opening.

In the modification illustrated in Fig. t I have shown the reflector 18 as of cylindrical form. In this embodiment or the invention while the reflected sound waves will not be directed to any particular point on the underside of the head, the space below the head will be restricted as before and the appearance of the instrument will remain unchanged.

I am aware that it has been suggested to stretch the head of a banjo over the ring supported by the hoop and spaced therefrom. I am also aware that it has been proposed to inclose the back of a banjo by means of a cover or member secured to the back end of the hoop and I do not claim such structures per 86.

In accordance with the provisions of the patent statutes I have described the principle of my invention, together with the apparatus which I now consider to represent the best embodiment thereof, but I. desire to have it understood that the apparatus shown is merely illustrative, and that the invention may be carried out in other ways.

Having thus described my invention what is claimed as new and desired to secure by Letters Patent, is

1. A banjo, comprising a hoop, a head, and a concave reflector, said reflector being disposed wholly within the hoop and in proximity to the head, said reflector engaging the head.

2. A banjo, comprising a hoop, a head, and a reflector, said reflector being disposed within the hoop and in proximity to the head, said reflector engaging the head at a distance from the hoop.

3. A banjo, comprising a head, a hoop, and a dished reflector, the rim of said reflector engaging the head at a distance from the hoop.

a A banjo, comprising a head, a hoop, and a dished reflector, the rim of said reflector engaging the head at a distance from the hoop and putting the head under tension.

5. A banjo, comprising a hoop and a head, said head being stretched across the hoop, a reflector carried by the hoop, said reflector being concentric with, and of less diameter than the head, whereby an annular space is formed between the hoop and the reflector, the edge of said reflector being beyond the plane of the end of the hoop whereby the head is given additional tension, there being an opening in the head, said opening being within that portion of the head bounded by the engagement of the edge of the reflector with the head.

6. A banjo, comprising a hoop, a head stretched over the hoop, there being an opening in the head, and a dished reflector disposed wholly within the hoop, the edge of the reflector en aging the head and surrounding said opening, said reflector being of less depth than that of the hoop, there being an annular space between the loop and reflector.

7. A banjo, comprising a hoop, a head stretched over the hoop, there being an opening in the head, and a dished reflector disposed wholly within the hoop, the edge of the reflector engaging the head and surrounding said opening, the greater portion of said reflector being concentric with the hoop, a relatively small portion of the re flector being eccentric, said reflector being of less depth than that of the hoop, there being an annular space between the hoop and reflector.

8. A banjo, comprising a hoop, a head covering the hoop, a bridge carried on the head, strings engaging the bridge and extending across the head, there being an opening in the head beneath the strings, a parabolic reflector disposed beneath the head and having a rim in engagement there- This specification signed and witnessed with, the opening being within that part this 26th day of January, 1920. of the head bounded by the rim, said i'eflector being so constructed and arranged 5 that sound waves set up below the head and Witnesses:

adjacent the bridge will be directed through J. F. COLEMAN, said opening. CLARIGE FRANCE.

FRED F. VAN EPS.

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