US1861105A - Loud speaker - Google Patents

Description

May 31, 1 932. ANDRES 1,861,105

LOUD SPEAKER Filed May 27, 1929 2 Sheets-Sheet 1 May 31, 1932. P. G. ANDRES I 1,861,105

LOUD SPEAKER Patented May 31, 1932 UNITED STATES PATENT OFFICE PAUL G. ANDRES, OF LA GRANGE, ILLINOIS, ASSIGNOR TO TEMPLE CORPORATION, OF

' CHICAGO, ILLINOIS, A CORPORATION OF DELAWARE LOUD SPEAKER Application filed. May 27, 1929. Serial N0. 366,421.

My invention relates to 'loud speakers, and has among its other objects the production of devices of the kind described that are eflicient, durable andsimple in construction.

A particular object of the invention is to provide improved means for bringing the reproducing unit or mechanism of a loud speaker into adjusted positions with respect to the diaphragm.

Another particular object of the invention isto provide improved-means for operatively connecting the diaphragm of a loud speaker to the reproducing unit thereof.

The preferred form of the invention is embodied in a loud speaker comprising a plurality of tensioned diaphragms which have their central portions operatively connected to a reproducingunit, the reproducing unit being provided with an armature disposed within a coilsubjected to telephonic currents. Improved adjustable means is provided for connecting 'the'diaphragm to the armature and the reproducing unit is mounted on a bracket which may be brought into adjusted positions with respect to the diaphragm to properly position the armature within the coil.

Many other objects and advantages will become apparent as this description progresses, reference being had to the accompanying drawings, wherein:

Figure 1 is a rear elevation of a loud speaker embodying the invention;

Fig. 2 is a section taken on line 2-2 of Fig. 1;

Fig. 3 is a section taken on line 33 of Fig. 1;

Fig. 4 is a Fig. 1;

Fig. 5 is a section taken on the line 55 of Fig. 1, and

Fig. 6 is a section taken on line 66 of Fig. 4.

In the drawings, I have illustrated my invention as embodied in a loud speaker comprising a plurality of diaphragms, but it is to be understood that my invention is limited to this construction only to the extent indicated in the appended claim.

The loud speaker illustrated in the drawsection taken on line 44 of ings preferably comprises a rectangular frame 10 provided with a pair of spaced cross-bars 11 to which a pair of spaced vertical bars 12 are rigidly secured. The diaphragm 14 is preferably formed from fabric,

or the equivalent, and has its marginal portions rigidly secured to the frame 10 and a smaller diaphragm 15 of like material has its marginal portions secured to the cross-bars 11 and the vertical bars 12. It will be noted that the diaphragms 14and 15 are tensioned along divergent lines and that they are somewhat conical in shape to provide apices which are aperture'd to receive a sleeve or bushing 17 (see Fig. 5). The apertured portions or apices of the diaphragms 14 and 15 are preferably re-enforced by washers 19 and and 20, respectively, preferably formed from fabric. diaphragms' are clamped to each other hetweenmetallic washers 21 and 22 positioned upon the sleeve or bushing 17, the sleeve or bushing 17 being provided with an outwardly extending flange 23 and a nut 24 for this purose.

One end of the sleeve or bushing 17 is preferably slotted longitudinally, and is preferably screw-threaded, as at 25, to receive a nut 26 having an extension 27. The extension 27 has a conical inner surface engageable, with a similar surface provided upon the slotted end of the sleeve orbushing 17. The construction is such that the nut 26 may be manipulated to clamp the slotted end of the sleeve or bushing 17 against a rod 30 to rigidly secure the rod to the sleeve. One end of the rod 30 is rigidly secured to a relatively flexible and resilient arm 32'which has one of In this instance, the apices of the its ends rigidly secured to a bracket member 1 33 by a screw 34, the other end of the arm 32 being secured to one end of a pin 35 which has itsother end secured to an armature 36 forming part of a reproducing unit indicated generally by reference character 87. It will As best shown in Figs. 1, 2 and 3, the bracket member 33 comprises a central disc portion 40 having integral arms 41, 42 and 43, the arms 42and 43 being secured to one of the bars 12 and one of the bars 11, respectively, by screws 45, or the equivalent. At its outer end, the arm 41 is provided with an aperture 48 to accommodate a rod 50 which has one of its ends rigidly secured to a cupshaped member 51 fastened to the uppermost bar 11. It will be noted that the cup-shaped member 51 is seated in a recess 53 formed in the bar 11 and that a compression spring 54 is disposed around the rod 50 and is interposed between the cup-shaped member 51 and the arm 48. The compression spring 54 tends to displace the bracket member 33 in a direction away from the diaphragms 14 and 15, but such displacement is limited by a knurled nut 56 screw-threaded upon the rod 50.

Secured to the bracket member 33 is a permanent magnet 60, the legs of the magnet being apertured to receive bolts 61 and 62 which co-operate with nuts 63 and 64, respectively, to rigidl secure I the magnet in place upon the brac et 33. The magnet is preferably Erovided with pole pieces 65 and 66 having -shaped ends which terminate adjacent the ends of the armature 36 (see Fig. 4). Disposed Within the U-shaped ends of the pole pieces 65 and 66 is winding 68 carried by a sleeve 7 O which is formed from non-magnetic material. The armature 36 is resiliently mounted within the sleeve 70 by any suitable means, such as, for instance, a relatlvely thin piece of sheet metal 7 2. As is well known to those skilled in the art when the winding 68 is subjected to telephonic currents, the armature 36 vibrates and this vibration is transagainst the action of the spring 54 or in the direction of the action of the spring 54 to properly position the winding 68 and sleeve 70 with respect to the armature 36 so that when the armature 36 is not energized, it will occupy a predetermined position within thesleeve.

While I have shown and described certain embodiments of my invention, it is to be understood that it is capable of many modifications. Changes, therefore, in the construction and arrangement may be made without departing from the spirit and scope of the invention as disclosed in the appended claim,

in which it is my intention to claim all novelty inherent in my invention as broadly as possible, in view of the prior art.

What I claim as new is:

A sound reproducing device comprising a frame, a diaphragm extending across said frame, a second frame mounted on the first mentioned frame, a second dia hra gm mounted on said second frame, a bracket having one of its ends secured to said second frame, a bolt secured to said second frame and extending through the other end of said bracket, a spring urging said bracket in one direction, a nut screw-threaded on said bolt and adapted to displace said bracket against the action of said spring, a sound reproducing unit mounted on said bracket intermediate its ends, said sound reproducing unit having an armature and means including a flexible member for operatively connecting said armature to said diaphragms.

In testimony whereof, I have hereunto set my hand this 17th day of Ma 1929.

- PAUL ANDRES.

mitted to the diaphragms 14 and 15 which translate them into sound.

The means for operatively connecting the windin 68 to a source of telephonic current, prefera 1y comprises conductors and? 6 connected to the terminals of the winding. The outer ends of the conductors 75 and 7 6 are connected to terminals 78 and 79, respectively, carried by a bar 80 formed of electrical insulation. The bar 80 is apertured to receive a bolt 82 screw-threaded through the bracket member 33 and nuts 83 screw-threaded upon the bolt secure the bar 80 thereto. Suitable conductors, as indicated at 87 and 88, may be provided to connect with the ter- 55 minals 78 and 79 to the output circuit of a radio-receiving set, or the equivalent.

Obviously, the nut 26 may be manipulated to clamp the slotted end of the sleeve 17 in any desired position upon the rod 30 so that 60 the diaphragms 14 and 15 will be correctly positioned with respect to the arm 32 and there will be no tendency to distort the sound waves propagated by the diaphragm. It is also apparent that the nut 56 may be manipu-

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