US1771266A

US1771266A - Radio loud-speaker

Info

Publication number: US1771266A
Application number: US349950A
Authority: US
Inventors: Mcconnell Charles
Original assignee: Individual
Current assignee: Individual
Priority date: 1929-03-26
Filing date: 1929-03-26
Publication date: 1930-07-22
Anticipated expiration: 1947-07-22

Description

July 22, 1930. c. MCCONNELL 1,771,266

RADIO LOUD SPEAKER Filed March 26, 1929 Patented July 22, 1930 PATENT OFFICE CHARLES MccormEL or NEW YORK, N. Y.

namo LOUD-SPEAKER Application filed March 26, 1929. Serial No. 349,950.

This invention relates to new and useful im rovements in loud speakers.

, he invention has for an object the provision of a device of the class mentioned 5 which is of simple durable construction, de-

pendable in use and eificient in action, and which can be manufactured and sold at a reasonable cost. I It is proposed to use a sound reproducing l diaphragm having a plurality of slightly spaced soundboard sections attached upon a membrane, each of the sections consisting of a fiat thin wooden strip, and a vibration spreader attached on the rear of the sound 15 board sections and connected with a loud speaker electro-magnetsupported on a frame arranged for also supporting the said membrane. I

This construction derives particular ad- 3 vantages in that vibrations set up by the electro-magnet and communicated to the diaphragm cause the sound board sections of the diaphragm to vibrate and reproduce the sound with a minimum amount of distortion by reason of the sound board sections being capable of deflecting independently from each other. It has been found that where the sound board of one complete piece, dis- 1 tortion is quite probable but with the board of several sections the distortion is materially reduced. i In the accompanying drawing forming a material part of this disclosure Fig. 1 is a front elevational View of a device constructed according to this invention. Fig. 2 isan end elevational view of Fig. 1. Fig. 3 is an enlarged rear'elevational view of Fig. 1. e

Fig. 4 is a vertical sectional View taken on the line H of Fig. 3.

Fig. 5 is a fragmentary detail sectional view of a portion of Fig. 4.

Fig. 6 is a sectional 66 of Fig. 3. e

Fig. 7 is a fragmentary view of a portion of Fig. 3 disclosinga modified form thereof. The reference numeral 10 indicates generally a frame consisting of a top longitudinal member 11, bottom longitudinal member 50 12 and side vertical members 13. A means view taken on the line 14 for supporting a loud speaker electromagnet is secured upon the rear of the frame 10 and supports a loud speaker electromagnet 15. This electro-magnet is connected with a sound reproducing diaphragm 16. The means 14 for supporting the loud speaker electro-magnet consist of a pair of spaced longitudinal strips 17 attached upon the rear of the frame 10 and joined by a vertical strip 18 offset from the vertical center of the longitudinal strips. The loud speaker electro-magnet is attached upon a support bracket 19 supported upon the said

strips

17 and 18. The vibration core of the loud speaker is indicated by numeral 20 and is connected with a needle post 21 which projects into a chuck 22 secured on a fiat semiring vibration distributor 23 by a nut 24. The chuck 22 serves to adjust the length of the needle post. I 1 The sound reproducing diaphragm 16 consists of a membrane 25 stretched tightly across the front of the frame 10 and held in position by molding 26. A plurality of slightly spaced sound board sections 27 are attached behind the rear face of the membrane 25, each of the sections consisting of a flat thin wooden strip. A vibration spreader is connected onthe rear faces of the sections 27 and consists of the said semi-ring vibration distributor 23 having spaced radial support strips 23 attached upon its front face, and radial vibration transmitting ribs 28 are attached upon the front of the strips and upon the rear of the said sound board sections 27. Preferably the ribs, the semi-flat ring, and the radial support strips should be of Wood, and glue used for fastening these parts as, before described. The free extremitiesof the ribs 28 should be reduced, as indicated by reference numeral 29.

In the modified form of the device illustrated in Fig. 7, a sound board section connector 30 has been illustrated engaged upon one of the sound board sections 27. A plurality of said connectors should be used upon all of the sections. Each of these connectors consists of a portion 31 disposed between adj acent edges of adjacent sections 27 and having an integral rear flat portion 32 extending over one of the sections 27 and formed with an inclined slot 83 thru whicn a locking screw 3 passes, This locking screw engages within the section 27 and serves to hold the connector in fixed positions. The connector should preferably be made of wood.

In operation of the device, the operation of the loud speaker electro-magnet 15 causes its core 20 to vibrate which vibrations are transmitted to the distributor 23. The chuck 22- may be loosened for changing the length of the needle post 21 to arrange for the proper transmission of vibrations. Vibrations communicated with the distributor 23 move on to the support strips and to the vibration transmitting ribs 28. The vibrations of the ribs 28 are next communicated to the sound board sections It is pointed out that the sections 27 may individually vibrate the bend as controlled by forces applied to these sections. Such individual vibration of the sepa rate boards tend to reduce distortion which would be likely if one portion of the sound board attempted to vibrate and force other portions into vibrations not in harmony with its attempted movement. Much better results are obtained by the use of individual vibration sections.

The length of ribs 28 are so arranged as to allow the dilferent frequency in the notes to be emphasized by the individual ribs due to the gradual variations in the length of the aid ribs. The short ribs bring out the high frequency notes whereas the long ribs 28 bring out the base or low frequency notes.

The connectors 30 may be moved for connecting adjacent sections. Such motion is permitted by first loosening the screws 34 and then movin the connectors against the adjacent sound board sections. A tightening of the screws hold the connectors in contact. This permits a control of the vibrations of the various sections communicating with each other and adjustments may be made for obtaining the most satisfactory tones by moving several or all of the connectors into operative positions.

While I have shown and described the preferre'l embodiment of my invention, it is to be understood that I do not limit myself to the orecise construction herein disclosed and the right is reserved to all changes and modifications coming within the scope of the invention as defined in the appended claims.

Havi g thus described my invention, what I claim as new, and desire to secure by United States Letters Patent is 1. A loud speaker, comprising a frame, a diaphragm attached on the front thereof, a loud speaker mounted on the rear of the frame and a vibration spreader connected between the loud speaker and diaphragm, said diaphragm consisting of a membrane and individual sound boards.

2. A loud speaker, comprising av frame, a

diaphragm attached on the front thereof, a loud speaker mounted on the rear of the frame, and a vibration spreader connected between the loud speaker and diaphragm, said diaphragm consisting of a membrane and individual sound boards, said vibration spreader including a flat semi-ring vibration distributor connected with a needle post, and radial vibration transmitting ribs.

3. A loud speaker, comprisin a frame, a diaphragm attached 011 the front thereof, a loud speaker mounted on the rear of the frame, and a vibration spreader connected between the loud speaker and diaphragm, said diaphragm consisting of a membrane and individual sound boards, said vib 'ation spreader including a fiat semi-ring vibration distributor connected with a needle post, and radial vibration transmitting ribs, the needle post being of two sections adjustably connected.

at. In a loud speaker, a diaphragm consisting of a meml'n-ane and a plurality of slightly spaced sounding board sections. a fiat semi-ring vibration distributor for connection with a loud speaker electro-magnet, and radial vibration transmitting ribs connected between the distributor and the board sections 5. In loud speaker, a diaphragm consisting of a membrane and a plurality of slightly spaced sounding board sections, a flat semiring vibration distributor for connection with a loud speaker actuating mechanism spaced from the rear of theboard sections, and radial vibration transmitting ribs connected between the distributor and the board sections.

6. In a loud speaker, a diaphragm consis ing of a membrane and a plurality of sli 'htly spaced sounding board sections, a flat semi-ring vibration distributor for connection with a loud speaker actuating mechanism spaced from the rear of the board sections, and radial vibration transmitting ribs connected between the distributor and the board sections, said board sections having soundboard section connectors for vib 'ationally connecting the sections.

7. In a loud speaker, a diaphragm consisting of a membrane and a plurality of slightly spaced sounding board sections, a flat semi-ring vibration distributor for connection with a loud speaker actuating mechanism spaced from the rear of the board sections, and radial vibration transmitting ribs connected between the distributor and the board sections, said board sections having sound board section connectors for vibrationally connecting the sections, each connector consisting of a portion disposed between adjacent edges of adjacent sections, and an integral flat portion extending over one sect-ion and adj ustably mounted.

8. A loud speaker, comprising a frame, a

diaphragm attached on the front thereof, a loud speaker mounted on the rear of the frame, and a vibration spreader connected between the loud speaker and diaphragm, said diaphragm consisting of a membrane and individual sound boards, said vibration spreader including a flat semi-rin vibration distributor connected with a need e post, and radial vibration transmitting ribs, said transmitting ribs arranged in palrs, each pair being of different length.

9. A loud speaker, comprising a frame, a diaphragm attached on the front thereof, a loud speaker mounted on the rear of the frame, transmitting ribs connected between the loud speaker and diaphragm, said diaphragm consisting of a membrane and individual sound boards, said transmittin ribs arranged in pairs, each pair being of di erent length, some of said transmitting ribs connect a plurality of the said individual sound boards.

In testimony whereof I have aflixed my signature.

CHARLES MOCONNELL.