US1817354A - Wireless loud speaker and the like - Google Patents

Description

Aug. 4, 1931. a. 6. DE ANDlA-YRARRAZAVAL 5 WIRELESS LOUD SPEAKER AND THE LIKE Filed April 16. 1929 Patented Aug. 4, 1931 UNITED STATES PATENT OFFICE WIRELESS LOUD SPEAKER AND THE LIKE Application filed April 16, 1929, Serial No. 355,564, and in Great Britain April 17, 1928.

This invention relates to sound amplifying devices such as those employed in connection with the wireless reception of sound.

Loud speakers embodying units of the moving coil or balanced armature type are recognized as being excellent not only in respect of volume of sound obtained but also in respect of the strength and purity of the reproduction of speech and music. It has, however, heretofore been considered essential, in order to obtain the best results and obviate distortion of the lower notes, to provide a rigid bafile so as to prevent alternate neutralization and reinforcement of the air waves simultaneously set up by both the front and back of the cone employed in these types of loud speakers.

According to the present invention a sound amplifier, preferably comprising a unit of the said moving coil, balanced armature, or similar type, is combined with a sound distributing cone or reflector and is so mounted and arranged that the use of a battle board as heretofore usually employed is dispensed with, the volume, purity and strength of the reproduction being even better than when a bathe board of usual character is used and the tonal range increased. The sound distributing cone or reflector is arranged axially in front of the mouth of a sound tube with the other end of which the receiving unit is associated.

The reflector may consist of a hollow saucerlike body so that the reflecting surface is backed by a cushion of air, or it may consist of a simple saucer-like body not made hollow whether or not provided with an air deflecting cone at its central portion. Alternatively the reflector may be of more or less cone or pear-shape and in this case also it may be a simple body or be made hollow to provide an air cushion.

In some cases the said cone or reflector is adjustable towards and away from the said sound tube; for example, it may be carried by telescopic rods, suitable means, such as a wing nut or wing nuts or any other appropriate device or devices, being provided to secure the cone or reflector in any position into which it is adjusted.

\Vith advantage the said sound tube is provided with a flange or other means whereby it can be mounted on a hollow support which can be made of any desired ornamental shape. The support may for example be shaped as 5 a vase and preferably it is open at the bottom and supported on feet, for example balls or semi-circular blocks of india-rubber whereby it can rest on a table or other supporting surface. It is found that with this 6 arrangement the higher notes mainly issue through the mouth of the sound tube and are distributed in all directions by the cone, and the lower notes mainly issue through the open bottom of the supporting vase or the 6 like.

Fig. 1 of the accompanying illustrative drawings shows in sectional elevation a construction of sound amplifier embodying the invention.

Fig. 2 is a plan of the improved sound amplifier.

The sound amplifier illustrated by way of example is embodied in a structure that constitutes an ornamental electric table lamp.

1 indicates a wireless receiving unit of the pivoted armature or moving coil type and 2 the stiff paper cone to which the moving coil of the said unit is fixed. 3 indicates the slotted metal cone that surrounds the paper cone 2 and which carries the magnet. The re ceiving unit, which is of known construction, is mounted as shown at the mouth of a sound tube 4 having a flange 5 which is screwed or otherwise suitably secured to a B flange 6 forming the lip of a casing 7 that is so shaped as to present the appearance of an ornamental bowl that in the example shown forms the base of an electric lamp. The said casing 7 is constructed of papier-mach but upper end of the sound tube. The said arms are hollow and are formed with curved tubular brackets 11 fitted with holders for electric lamp bulbs 12, the electric conductors for said lamps being led through the tubular brackets and away from the lamp in any suitable unobtrusive manner.

With advantage, but not necessarily, the sound tube is formed with a number of holes 13 arranged in downwardly inclined rows and gradually increasing in size from the highest downwardly.

Preferably the cone 9, which is formed of papier-maoh or other suitable material, is hollow and is closed at its larger or top end by an inverted saucer-like cover 9 formed in one therewith, the said cover being also, it may be, formed with holes as shown in the plan view, Fig. 2.

The receiving unitis carried by a flange l-l located between the flange 5 of the sound tube and the flange 6 of the bowl or casing. If desired a packing ring 15 of felt or other material may be located below the flange 5 of the soundtube, as shown.

16 indicates in dotted lines an art shade carried by a suitable frame that may be sin ported on the dome of the sound tube and vhich when in place surrounds the lamp bulbs, sound tube, and sound distributor, so that the loud speaker as a whole does not in appearance differ from that of an ornamental table lamp.

It is an advantage. in order to avoid resonance, to make the reflector or conical sound distributor so that its peripheral edge or larger end does not terminate in a free edge and this is done in the example illustrated by making the reflector or conical sound distributor hollow and closing the larger end thereof by a cap or cover the edge of which is united to the rim of the larger end of the conical reflect This cap or cover is preferably of dome or saucer-shape, as shown, and as will be understood the construction is such that an endless path is provided for the vibrations up in the reflector and resonance detrimental to pure delivery of sound is prevented. With advantage the reflector and cap or cover are made of one and the same moulded material but the invention is not restricted in this respect as any suitable material or materials may be used in the construction of the reflector or sound distributor.

The sound reproducing unit at the inner end of the sound tube can be of any desired type but as before stated surprisingly good results are obtained if the said unit is of the moving coil, balanced armature, or similar type.

As will beappreciated the conical reflector is not necessarily a strict cone, andthe pointed end of the reflector can be any desired disance from the mouth of the sound tube instead of entering the same.

An advantage of a reflector of the char-ac ter described is that the sound waves impinging thereon are outwardly directed in all directions and an advantage of making said reflector adjustable if so desired is that the volume and density of the sound delivered can be varied by such adjustmentand the best possible results obtained according to the type of sound being reproduced.

'hen the sound tube is arranged vertically with the conical reflector over the upper end or mouth thereof, which the preferred arrangement, it is a simple matter to give the apparatus an ornamental appearance. In the example shown the whole article has the appearance of and functions as a table lamp as well as a loud, speaker from which the sound issues in all directions.

The improved sound amplifier with reproducing unit attached can be used either for wireless reception or for phonograph reproduction through any suitable pick up.

What I claim is:

1. A loud speaker, comprising a casing. a loud speaker unit inclosed therein, a converging sound tube having its larger end secured to the top of the casing and having a sound outlet at its upper part, and a hollow sounddistributing cone supported over the upper end of the sound tube with its smaller end portion projecting downwardly into it.

2. A loud speaker as setforth in claim 1, the said sound casing being open at its bottom and provided with legs so as to provide an additional sound outlet.

3. A loud sneaker as set forth in claim 1, and provided with upwardly projecting arms having their lower ends secured to the sound tube and supporting the said cone.

l. A loud speaker as set forth in claim 1, the said cone being provided at its upper and larger end *ith a. hollow perforated cover which projects laterally of the top edge of the said cone.

In testimony whereof I atlix my signature.

GABRIEL GONZALEZ de ANDlA-YRARRAZAVAL

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