US1839137A

US1839137A - Telephonic loud-speaker

Info

Publication number: US1839137A
Application number: US402753A
Authority: US
Inventors: Wunner Alois
Original assignee: Individual
Current assignee: Individual
Priority date: 1928-11-01
Filing date: 1929-10-26
Publication date: 1931-12-29
Anticipated expiration: 1948-12-29

Description

Dec. 29, 1931. A. WUNNER I TELEPHONIC LOUDSPEAKER Filed Oct. 26, 1929 Patented Dec. 29, 1931 ALOIS wurmnn, or ma age, GERMAVNFI TELEPHONIC LouDssrEAKEn.

Application filed October 26, 1929, Serial No.

This invention relates to a telephonic loud speaker of the kind wherein the vibratory armature of a magnet system is connected by means of a needle to an acoustic dia- O phragm. Usually the diaphragm is connected at a single point to the needle. The latter therefore vibrates at right angles to the diaphragm, and it is necessary to support the latter more or less rigidly. at the outer edges, an arrangement which leads to a distortion of the sound. The object of the present invention is to produce an arrangement allowing the diaphragm full freedom of movement, and the invention consists in arranging the diaphragm parallel to the needle connecting it to the latter throughout the length thereof.

Fig. 1 of the accompanying drawings represents a sectional view of one form of the improved loud speaker, I

Fig. 2 is a front view of the same,

Fig. 3 is a sectional view of a modified form,

Fig. 4 is a front view of the latter, and

Fig. 5 is a side view of a still further form.

The loud speaker comprises the usual magnet system 1 which receives current through leads 7 and which is provided with an adjusting screw 8. The vibratory armature strip 2 of the-magnet system is supported at both ends and carries, at substantially right angles, a needle 3 which is connected throughout its length to an accoustic diaphragm 4 so as to hold the latter parallel to its own plane, i. e., substantially at right angles 'to the armature 2. The diaphragm, which is preferably rectangular in shape, is formed with a channel 5 for the reception of the needle the surface of which is preferably screw threaded or otherwise roughened so as to form engaging points all along the needle.

In the arrangement shown in Figs. 1 and 2, there is only one needle and this is placed in a central position on the armature 2. The diaphragm is extended beyond the needle, and the projecting portion is coiled so as to form a cylindrical or conical sound magnifier 6. When the armature 2 is vibrated underthe influence of the magnetic impulses, the vibrations will be transmitted to the diaphragm 4 402,753, and in Germany November 1, 1928.

principally in the direction of. the arrows A. The diaphragm will alsobe oscillated in the directions about its connecting point with the armature'2. -The air column within the cylinder orcone 6 will be set in correspond ing vibrations, and a considerable sound volume, faithfully reproducing theoriginal sound, will be obtained from the-arrange ment.

The sound-magnifier 6 may be of oval or annular cross-section instead of round, and it may be provided with -apertures,- reinforce-' merits, coatings or insertions with a view to' modifyingthe sound and regulating the 'volume. The diaphragm itself may be treated in asi'milanmanner and-it'may be bent indifferent directions if required. Naturally a perfectly straight andcontinuous diaphragm may also be used.

The entire device may be modified, for instance as shown inFigs. 3 and 4, where two or more needles are provided to which the two limbs of U-shaped diaphragm are connected. p

A further modification is shown in Fig. 5 wherein a U-shaped diaphragm is connected to the needles of two separate magnet systems.

The diaphragm may be made of any suitable material such as paper, cardboard, wood, metal, glass or the like, and the rigidity may be varied according to requirements. Tension may be applied to the diaphargm in one or more places if necessary. The length of the needles relativeto the diaphragm may be varied.

Thedevice, which'can also be used in connection with condenser telephones, is preferably mounted by means of feet on a resonant base. r

I Being of simpler construction than the usual loud speakers, the loud speaker according to the present inventionwill also be considerably cheaper.

I claim 2- A o 1. A telephonic loudspeaker comprising a magnet system fitted with avibratory armature, a needle carried'by said armature, and an acoustic diaphragm connected to said needle throughout the length of the latter.

2. A telephonic loud speaker comprising a magnet system having a Vibratory armature, a needle carried by said armature and maintained substantially at right angles thereto,

5 and an acoustic diaphragm arranged parallel to the needle and connected thereto throughout the length of the needle.

3. A telephonic loud speaker as claimed in claim 2 wherein the diaphragm is formed 10 with a channel for the reception of the needle.

4. A telephonic loud speaker as claimed in claim 2 wherein the needle is formed with an uneven surface for engagement With the diaphragm.

5. A telephonic loud speaker comprising a magnet system having a vibratory armature, a pair of needles carried by said armature and arranged substantially at right angles thereto, and an acoustic diaphragm having channels for the reception of said needles.

6. A telephonic loud speaker as claimed in claim 5 wherein the diaphragm is U-shaped and has its limbs connected to different needles.

7. A telephonic loud speaker comprising a pair of magnet systems having vibratory armatures, a needle carried by each armature at substantially right angles thereto, and a U-shaped acoustic diaphragm having each limb connected to the needle of a different magnet system and throughout the length of the needle.

ALOIS WUN N ER.