US2496988A - Megaphone, including mouth- and earpieces - Google Patents

Description

Feb 7, 1950 c. CUNNINGHAM 2,496,988

MEGAPHONE INCLUDING MOUTH AND EAR PIECES Filed Jan. 18, 1946 2 She ets-Sheet l 6 60/7 Czmm'q a/mm Feb. 7, 1950 C. CUNNINGHAM MEGAPHO NE INCLUDING MOUTH AND EAR PIECES 2 Sheets-Sheet 2 Filed Jan. 18, 1946 Patented Feb. 7, 1950 MEGAPHONE, INCLUDING MOUTH- AND EARPIECES Cecil Cunningham, East Orange, N. J

Application January 18, 1946, Serial No. 641,949

2 Claims. 1

This invention relates to megaphones and in particular to megaphones having a sound receiving attachment, which may be mounted on a swivel joint, and turned to inoperative position, if desired.

A principal object of the invention is to provide a device of the above character which shall be of improved arrangement and construction.

A further object of the invention is to provide an improved megaphone which shall be compactly constructed, and which shall be capable of conversionfrom a sound-projecting device to a sound receiving device b simple manipulation of a conveniently located lever.

With the above and still further objects in view, which will be made apparent hereinafter, the invention consists in certain novel constructions, arrangements and combinations of parts which will be fully described in the following specifications, illustrated in the accompanying drawings, and particularly defined in the appended claims.

Reference isnow had to the accompanying drawings wherein like characters of reference indicate like parts throughout the several views, and wherein:

Figure; 1 is a front elevational view of the device embodying the invention, and showing in dotted and full lines, two positions which may be assumed by one element of the device;

Figure 2 is a plan view of Figure 1, without the dotted-lines;

Figure 3 is a median section of the device taken on the line 3-4; of Figure 2 and illustrating various interior details;

Figure 4 is a plan view of the mouthpiece and adjacent parts of the device;

Figure 5 is a sectional view taken on the line 5--5 of Figure 1;

Figure 6 is a plan view of the earpiece associated with the device; and

Figure 7 is a sectional view taken on the line 1--! of Figure 1; and

Figure 8 is a plan view of an element of the device.

The sound transmitter and receiver horn consists of a hollow, tapered body I of generally square cross section having open ends and tapering from its large to its small end in accordance with a gently sloping curve 2, which may follow a logaritlnnic law. While I have disclosed a horn of square cross section, it is to be understood that my invention may be practiced with horns having other cross sections, and that I do not desire to be limited to square cross sections.

At the mouth 3 of the horn is provided a mouthpiece 4, which is slidably translatable into and out of the end 3, as a means of adjustment to suit the needs of various users. The mouthpiece 4 is of generally square cross section and provides a close sliding fit'with the mouth 3 of the horn but flares slightly at its outer extremity 5 and evolves into a shape of circular cross section 6, adapted to fit the mouth of the user.

In the upper wall of the horn end 3 is provided a longitudinal slot 7 providing access for a stub screw 8 extending upwardly from and secured to the mouthpiece 4. After longitudinal adjustment of the mouthpiece 4 within the mouth 3 has been accomplished the said mouthpiece A may be fixed relatively to the horn by means of a thumb screw 9, which threadably' engages the stub screw 8 and clampsthe upper wall of the horn end 3 against corresponding wall of the mouthpiece 4.

Secured against the underside of the upper wall of the throat Ill of the horn by means of screws l I, is a'fianged ring [2 having a generally rectangularly shaped base having a circular aperture 13 therein, and from which extends an annular flange M provided with a convex outer surface i5, which engages with'an annular groove IS in an earpiece IT, to provide a swivel joint for the said earpiece}. The upper wall of the horn is provided with a" circula aperture, registering with aperture I3 of member i2.

An annular clamp I 3 comprising a clamping screw l9 substantiall surrounds the earpiece I! over the annular groove 16, and tightening of said screw 19 serves totighten the clamp is and thereby to compress the annular groove [6 in the earpiece I'l against the annular shoulder 15 of the member !2, when such adjustment is desired.

The earpiece I1 is provided with an ear tip 20 of generally rounded cross section adapted to be inserted slightly only in the car, which extends generally perpendicularly to the center line of the horn; the earpiece l1 flares to a square cross section over a portion thereof which substantially extends parallelly to the center line of the horn, following however a slight and graceful curve, pleasing to the eye. The large end 2| of the earpiece ll, flares from a substantially square cross section to a circular cross section at the annular shoulder [5, simultaneously bending to take a direction at right angles to the center line of the horn, or parallel to the axis of the annular shoulder I5.

Secured to the tip 20 in any convenient manner may be provided an earpiece 22. For example the earpiece 22 may be of rubber or plastic and may be pressed on the tip 20, and secured adhesively or by means of a set screw. However, the mode of securing earpiece 22 to tip 20 is not part of my invention. The use of an earpiece is recommended in connection with my invention, but is not necessary, since the shoulder 29 will obviate the possibility of harming the ear of the user by careless insertion of the tip 20 too far into the ear.

Extending through the upper wall of the throat I just forwardly of the longitudinal slot i is a further transverse slot 23, which receives a crankshaft 24 having a crank 25 extending externally of the horn and a shaft 26 extending across the throat I!) and bearing in the side walls of said throat i9. Surrounding a portion of the shaft 26 is a coil spring 21 one end'of which extends under and is secured to a valve or baffle 28-, the other end being secured in any convenient manner. The spring 21 serves to retain valve or baffle 28 in the position shown in full lines in.

Figure 3, to provide clear passage for sounds outgoing from the megaphone, and to block, at the same time, passage to earpiece l1. When it is desired to use thedevice as an audiphone the baffle 28 is depressed by actuation of crank 25, thereby providing a clear passage from mouth of the horn to the earpiece I].

In use, the device is supported by the hand with the mouthpiece 4 adjacent the mouth, the earpiece l1 extending about the face to support earpiece 22 or tip adjacent to the ear. Crank 25 in unactuated position enables baiiie 28 to protect the ears from sounds projected into mouthpiece 4 when the deviceis used as a megaphone, by blocking the passageway to earpiece l1. When used as an audiphone, however, crank 25 is actuated by a finger of the hand supporting the device, to block the passage to the mouth pieceA, and thereby causing all received soun energy to flow to the earpiece I 1.

When the device is not in use earpiece I! may be rotated 180 degrees about its swivel joint I5, IS to the position shown in dotted outline in Figure 1, to provide compact stowage.

What I claim is:

1. A convertible megaphone comprising an elongated, tapered horn having open ends, a throat portion adjacent the smaller end and a lateral opening through the wall of said throat portion, a mouthpiece detachably secured in the smaller end of said horn, a flanged ring secured in said throat portion with the annular flange thereof extending through said lateral opening;

a rigid, tapered tube having curved end portions receiving said annular flange in its larger end, the smaller end of said tube being shaped to provide an ear-piece, means carried by said tube at the larger end thereof operative to adjustably secure said tube to said flanged ring, a shaft extending through the throat portion of said horn at the side of said lateral opening adjacent the smalier end of said horn, a crank on said shaft, and a baffle in said throat portion secured at one end to said shaft and movable by said crank between a position in which it closes said lateral opening and .a position in which it closes the smaller end of said horn.

2. A convertible megaphone comprising an elongated, tapered horn having open ends, a throat portion adjacent the smaller end and a lateral opening through the wall of said throat portion, a mouthpiece detachably secured in the smaller end of said horn, a flanged ring secured in said throat portion with the annular flange thereof extending through said lateral opening, a rigid, tapered tube having curved end portions receiving said annular flange in its larger end, the smaller end of said tube being shaped to provide an ear-piece, means carried by said tube at the larger end thereof operative to adjustably se-' cure said tube to said flanged ring, a shaft extending through the throat portion of said horn at the side of said lateral opening adjacent the smaller end of said horn, a crank on said shaft, a bafile in said throat portion secured at one end to said shaft and movable by said shaft betweena position in which it closes said lateral opening and a position in which it closes the smaller end of said horn, and spring means operatively connected with said bafile resiliently urging said baiiie to its position closing said lateral opening.

CECIL CUNNINGHAM.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 404,868 Rush June 11, 1889 454,399 Cutmore June 16, 1891 630,990 Salmond Aug. 15, 1899 652,926 Salmond July 3, 1900 918,111 Woods Apr. 13, 1909 958,680 Purcell May 17, 1910 1,145,146 Johnson July 6, 1915

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