US1717778A - Sound amplifier - Google Patents

Description

June' 18, 1929. m c 1,717,778

sourm AMPLIFIER Filed June 27, 1927 2 Sheets-Shet 1 FIG- 1 I r 7 7 iii F 5 an [(5. x as 7 as so z3 as 4/ a? A 5 INVENTOR FRANK C. HmcKuzY K4 Patented June 18, 1929.

UNITED STATES PATENT OFFICE.

FRANK .G. HINCKLEY, F STRATFORD, CONNECTICUT, ASSIGNOB TO COLUMBIA PHONO- GRAPH COMPANY, INC., 01 BRIDGEPORT, CONNEGTICU T, A CORPORATION OF NEW YORK.

L SOUND AMPLIFIER.

Application filed June 27,

This invention relates to new and useful improvements in sound amplifiers, or amplifying systems, and has particular reference to that type of amplifier for use in sound reproducing machines, such as phonographs, talking machines, loud speaking telephones and radio receiving apparatus.

An object of the invention is to provide a. means which will more accurately amplify the sounds passed therethroughl Another object of the invention is to provide an amplifier of the type indicated, which may be constructed with a phonograph cabinet to form a part thereof, or which may be constructed as a unit separate therefrom and secured therein.

A further object of the invention is to provide a two-way horn, comprising an upper main horn and a lower main horn, of substantially equal dimensions, the sound being divided before it enters these two horns and part goin to each.

A still urther object of the invention is to provide an amplifier, includin a tone cham- 5 her, a dividing means and a pa r of horns, the dividing means including means whereby each of the horns is fed substantiallythe same proportion of the sound to be amplified.

Additional objects and advantages will become apparent from a consideration of the following description taken in connection with the accompanying drawings, wherein:

Fig. l is a front elevation of a cabinet equipped with the improved amplifier;

Fig. 2 is a side view of a cabinet, looking from the right of Fig. 1, the side wall bein removed; 4

Fig. 3 is a horizontal sectional view on the line 3-3 of Fig. 1; and

- Fi 4 is a fragmentary sectional view-on the line 4 -4 of Fig. 2.

Referring in'detail to the drawings,the sound to be amplified is delivered from the tone-arm, or its equivalent (not shown) to a conduit, or coupling member 5, which may be made of die cast metal, preferably aluminum. On leaving the coupling member 5, the sound enters the tone chamber 6 from whence it is delivered to a dividing means '7.

Tone chamber 6 is made entirel of wood, and comprises two diverging si e walls 8 y and 9 respectively, a rectangularly-shaped front wall 1 0 and a rear wall 11. The rear 1927. Serial No. 201,682.

wall 11 also forms the back of the dividing means 7 and the back of the cabinet. On leaving the tone chamber 6, the sound enters into the dividing means 7.

The dividin means 7 comprises a bottom 12, a pair of s ort top boards 13 and 14 respectively, arranged to have their opposed edges in engagement with the lower edges of the diverging walls 8 and 9, and a pair of end blocks 15 and 16 respectively. These end blocks space the top and bottom boards apart and have their inner surfaces curved, as best shown in Fig. 3, for reasons which will be obvious. The front central portion of the dividing means is closed by means of a board 17, while its back is closed by the board 11, as above described.

Arranged centrally, within the dividing means, and extending transversely thereof, is a wedged shaped dividing block 18, which divides the sound into two columns. This dividing block causes the sound delivered to the dividing means to pass in substantially equal amounts to the lateral passages 19 and 20, to be discharged through the exit openings 21 and 22 at the respective ends of board 17.

It is to be noted particularly that the dividing means is arranged horizontally, and is in the form of a rectangle. Further, it will be noted that the two exit openings 21 and 22 are in the same plane, both horizontally and vertically. The area of the bottom opening of the tone chamber equals the combined crosssectional area of the lateral passages 19 and 20 respectively, which are disposed within the dividing means.

When the sound is discharged through exit openings 21 and 22, it is delivered or directed into a. pair of horns, comprising an upper main horn 23 and a lower main horn 24:. These horns are'diagonally disposed with relation to each other.

Upper main horn 23 is made up of sections, and includes an upwardl inclined top wall 25 and a vertically flaring inner wall 26, which increases in height towards its discharge end. The bottom of the upper main horn is formed by a board 27, which along one edge contacts with the side wall 28 of the cabinet, and whose other edge is inclined and contacts with the wall 26 of thehorn, as best shown in Fi 3. This board extends from the lower edge 0 the exit opening 21 to the forward edge of the cabinet, and as is readily apparent from an inspection of Fig. 1 the board slopes upwardly so that its forward edge is in a ,plane with the horizontal center of the dividing means 7. As will be readily apparent from a study of the drawings, this board 27 separates the main upper horn from the main lower horn. The vertical board 28 forms the outside wall of the upper main horn, and also may form the outside wall of the cabinet, or other housing means.

Board 27 which as stated above, forms a dividing means between the upper horn and the lower horn, also forms a part of the top wall of the lower horn. There are also two angularly disposed boards 29 and 30,-whicli form the remainder of the top wall of the lower horn.v Occasion for the use of these boards results from the fact that the exit openings 21 and 22 are in the same plane, and

that the horns 23 and 24 incline upwardly.

The outer end portion of the vertically flared inner wall 26 of the top horn 23 forms a dividing line, or partition, between that portion of the top wall of the lower horn, which is also the bottom of the upper horn, and these two angularly disposed boards. Board 29 is in the shape of a triangle, and is larger in area than board 30, which might also be said to be in the form of a triangle. These boards slope downwardly from the upper edge of the exit I opening 22 towards-the front or discharge end of the lower horn and terminate ,in a plane its front edge downwardly for a distance andthen inclines upwardly. The downwardly inclined portion of the edge contacts with the under side of partition 27, while theupwardly inclined edge is engaged by one edge portion of the triangular board 29'. Through the use of the triangular boards 29 and 30, and the double inclined edge of board 31, a full open throat is provided for the lower horn.

For acoustical reasons, I have found it desirable to construct my horns in the manner above stated, as a more faithful amplification of the original sounds is obtained."

While I have shown and described preferred and satisfactory embodiments of the invention, it will be understood that the disclosure is entirely by way of illustration and is not for the purpose of-limitation. Various modifications of the invention, within the scope of the appended claims, will readily suggest themselves to those skilled in the art. Therefore, the invention not being lmited to the disclosure, reference must be had to the appended claims for a definition of the limitations of the invention.

What is claimed is:

1. In a sound amplifier, a tone chamber, a dividing means, said tone chamber adapted to deliver sound to said dividing means, said dividing means comprising a pair of lateral passages, a dividing block directing sound into each of said passages, an upper main horn, a lower main horn, said dividing means delivering sound to each of said horns, and said horns being diagonally disposed with relation to each other.

2. An amplifier, including a box-like dividing means having an exit opening in its front wall adjacent each of its ends, said exit openings being in the same plane both horizontally and vertically, and a pair of horns arranged one above the other and each of said horns being fed from one of said exit openings. I

3. In an amplifying means, a dividing means comprising a rectangular box-like structure having a dividing block and a pair of lateral passages, said amplifier having an exit opening in its front wall at the end of each of said passages, said passages being in the same horizontal plane, and a pair of superimposed horns receiving sound from said passages.

4. An amplifier, comprising a dividing means having a spaced'pair of exits arranged in the same horizontal plane, a pair of horns each receiving sound from one of said exits,

said horns being arranged one above the other, the bottom of the upper horn inclinin upwardly and forming a part of the topof said lower horn.

5. In an amplifier, a dividingmeans, said dividing means comprising a rectangular box-like body having an opening. in its for-. ward side adjacent each of its ends, a pair of lateral passages in said dividing-means, one' terminating at each of said exit openings, a wedged-shaped dividing block for directing sound to be amplified into each of said pas-- sages,'and a pair of blocks one adjacent each of said exit openings, each of said blocks having a curved surface for deflecting the soundv from the lateral passages through the exit openings.

6. An amplifier, including a box-like dividing means having an exit opening in its front wall adjacent each of its ends, said exit openings being in the same plane both horizontally and vertically, a pair of horns arranged one abovethe other and each of said horns being fed from one of said exits, and the bottom of the upper horn forming a part of the top of the lower horn.

7. An amplifier, including a box-like dividing means having an exit opening in its front wall adjacent each of its ends, said exit openings being in the same plane both horizontally and vertically, a pair of horns arranged one above the other, and each of said horns being fed from one of said exits, the bottom of the upper horn being inclined upwardl and forming a part of the top of the lower horn, and that portion of the top of the lower horn adjacent the opening with which said lower horn is connected, inclining downwardly.

8. An amplifier comprising a pair of horns arranged one above the other, said horns being diagonally disposed with relation to each other, and the bottom of the upper horn inclined upwardly and forming a part of the top of the lower horn.

9. An amplifier comprising a pair of horns arranged one above the other, said horns being diagonally disposed with relation to each other, and the bottom of the upper horn forming a part of the top of the lower horn.

' Signed at Bridgeport, in the county of Fairiield, and State of Connecticut, this 22nd day of June, A. D. 1927.

FRANK C. HINCKLEY.

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