US1643228A - Phonograph - Google Patents

Description

Sept, 20,1927 B. STUMP PHONOGRAPH Filed July 29, 1922 2 Sheets-Sheet 1 INVENTOR. 5. STU/WP,

ATTORNEY.

Patented Sept. 20, 1927. 4

BURDETTE STUMP, F DEhIVER, COLORADO.

,PHONOGRAPH.

Application filed July 29,

This invention relates to improvements in phonographs and its primary object is toproduce an instrument in which the sounds reproduced by the vibratory motion of a diaphragm actuated by the movement of a stylus through the grooves of a phonograph ic record, are transmitted to the ear, in

clear, mellow and distinct tones. Another object of the invention is to ro-- vide av phonograph in which the reproduced sounds are enhanced by reenforcemen't of the vibrations of the diaphragm, and still further objects reside in details of construction and a novel arrangement'of parts, fully set forth in the following description with reference to the accompanying drawings.

In the drawings in the several views of which like parts are similarly designated,

Figure 1 represents a partially sectional front elevation of my improved phonograph; Figure 2, a vertical'section through'the instrument, partially in elevation, takenon the line 2'2 in Figure 4; 1 I

Figure 8, a transverse,horizontal section on the line 3*3, Figure 2;

Figure 4%, a vertical section taken on the line 4-4c, Figure 2;

Figure 5, a section along the line 5+5, Figure 4: drawn to an enlarged scale;

Figure 6, a horizontal section along the line 6-6, Figure 4; and i Figure 7, a fragmentary section 'on the line-77, Figure 4.

The most important and essential feature of the invention resides in theprovisioh of a hollow metallic element which is connected with a vibratory sounding board over which the sound waves move while'being propagated through the air; another feature is to so arrange the conduit through which the sound produced by the vibrating diaphragm, passes to the tone-chamber of which the sounding board is a part,that the motion of each sound wave is transmitted to the walls of the chamber and through said walls to certain auxiliary metal elements which by sympathetic vibration aid in its amplification and purification; and still another fea ture is to provide means for limiting the vibratory motion of the walls of the instrument and thereby steady and sustain the tones produced therein by weight and advantageously applied reenforcements.

Referring now to the drawings, the reference character 2 designates a phonograph casing or cabinet of conventional size and 1922, SeriaI No. 578,347.

form whichby means of partitions 3, 4i and 5 1s dlvlded into a motor chamber 6, a pr1- mary tone chamber 7' and a secondary tone" chamber 8.

. The walls of the casing are made of comparat'ively heavy wood to prevent excessive vibration, and the bottom is for the same purpose, weighted by means of ametal plate 9..

A motor 10 in the chamber 6 is operatively connected with a rotary turntable 12 upon which the phonographic records are supported.

Arotary hollow tone arm 13 and a reproductive sound box 14: at the free end thereof,

an elbow 18 constituting the throat of the primarytone chamber. v

The latter-is composed of four diverging sides of which the before mentioned partitionst and 3 are the upper-and lower ones.

An upright partition 19 inxthe rear end of the tone chamber provides a compartment 20in which the elbow is fitted.

It is an' important feature of the invention that thi's'elbow touches the four walls of the compartment as clearly shown in Figure 5, since by these means the vibrations of the sound waves are communicated to the walls 'of the chamber and indirectly to the walls'of the cabinet. i

The partition 19 has an-opening to receive the open 'end'of the metal throat and the latter is formed with a number of flutes or corrugations 18 as best shown in Figure 5, which'give direction to the tone waves alid'prevent them fromcrowding or blending together. i

Y The lower wall 3 of the tone chamber is loose at its forward edge and constitutes a the record to reproduce excessive vibration and sustains and steadies the tones as they pass through the metal throat, and a similar plate 22 is placed inside the motor chamber between the partitions 4 and 5 for the same purpose.

The funnel-shaped primary sounding chamber, the upright sides of which are designated by the numerals 23 and 24, is open at the front of the casing and its opening may, if so desired, be covered by a nonmetallic ornamental screen 25.

Loosely suspended from the lower side 3 or sounding board of the primary sounding chamber inside the lower and secondary chamber, is a hollow metal vessel 26 which in the construction shown in the drawings, is made in the form of a cylindrical kettle. The vessel is suspended from a hook in the center of the sounding board by means of a non-metallic strap 27, preferably made of leather, and its movement is restricted by.

two spiral springs 28 which connect its bottom portion at diametrically opposite points, with the side walls of the casing.

hen in the operation of the instrument, the sounding board vibrates by the tone waves propagated from the throat through the gradually widening tone chamber, its motions are transmitted to .the metal vessel which being capable of independent vibration, enhances the sound, and greatly improves the character of the tones by a meltion of foreign noises.

An inverted gong 29 supported on the bottom of the vessel serves to adapt it to instrulowing and separative effect and the absorpments of'difi'erent sizes and tone-reproducing qualities. it having been found that by varying the size of this gong or by placing two or more on the same support, the vessel may be attuned to any instrument.

It is essential thatthe hollow metal body be suspended from the lower wall of the tone chamber, free for independent vibration and through the medium of a non-me tallio member which prevents diffusion of the transmitted tones.

It will be evident that the tone waves passing through the throat of the tone chamher not only vibrate the walls thereof by their direct contact with the throat but also indirectly vibrate the walls of the casing. These vibrations are taken advantage of to further improve the character of the reproduced sounds, by equipping the walls with metallic resonant elements, of a type similar to that connected with the bottom of the tone chamber.

These elements may be of different form,

construction and proportions, according to the size and character of the instrument to which they are applied and it should be understood that their design and arrangement as shown in the drawings, may be varied to accord with different instruments. without departing from the spirit of my invention.

In the drawing, two bells 30, a gong 31. an aperturedtube 32 and a spiral spring 33 are connected with the rear wall of the instrument, it being apparent that the spring.

performs to some extent the function of a hollow body.

A gong 34 is fastened to one of the side walls of the cabinet. a double gong 35 is applied to the opposite wall of the same, a similar arrangement of gongs 36 is attached to the upper wall of the primary tone chamber inside the motor chamber and a pair of heavier gongs 37 is supported on the heavy metal-weighted bottom of the casing, which is less' subiect to vibration.

Aside from their purifying, amplifying and mellowingeffect upon the sound waves produced in the operation of the instrument, the difierent parts and features of construction hereinabove described, co-operate to separate and classify the tones and thereby prevent the undue blending and unharmonious mingling often observed in phonograph instruments of ordinary construction.

Having thus described my improve-d phonograph, I desire it understood that varia-. tions in the arrangement and construction of its co-operative parts, other than those hereinbefore referred to, may be resorted to within the. scope of my invention, as defined bylthe hereunto appended claim. b

What I claim and desireto secure by Letters Patent is: i

In a phonograph,a cabinetprovided in its upper portion with a tone chamber eXtending from frontto rear and taper-ed longitudinally, said tone chamber being composed of top, bottomand side walls, the bottom wall having its front edge free and constituting a sounding board, a resonator consisting of an open cylindrical metallic vessel suspended at its open end from the bottom wall of the tone chamber andarranged in spaced relation with the walls and bottom of the cabinet, and opposite spiral springs connecting theclosed bottom of the resonator with the walls of the cabinetat diametrical- 1y opposite points.

In testimony whereof I have aflixed my signature.

BURDETTE sTuMP.

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