US1803892A - Loud speaker - Google Patents

Description

May 5, 1931. J. T. CORRIGAN ,803,892

LOUD SPEAKER Filed April 12, 1927 gnueufoz Jam 2: (brag an $51 OMJM Patented May 5, 1931 JAMES T. GORR-IGAN, OF WASHINGTON, DISTRICT OF COLUMBIA LOUD SPEAKER Application filed April 12,

My invention relates to new and useful improvements in sound reproducing devices and more particularly to what is commonly known as a loud speaker.

'5 One of the objects of the present invention is to produce a loud speaker in which there is located an actuating unit, which in turn effects two or more diaphragms of difierent area and naturally of difi erent frequencies, so

that both the low notes and the high notes may be faithfully reproduced.

Still another object of the invention is to produce a loud speaker having two difierent size diaphragms actuated by the one electrical unit and to so proportion the diaphragms that the reproducing will produce a musical note and its harmonic thereby adding timber or colour to the tone.

Still another object of the invention is to provide a reproducer or loud speaker having two different size diaphragms actuated simultaneously by the one electrical unit, the two diaphragms being connected to each other and to the one unit, and to further provide two cylinders, one of the cylinders being secured to the smaller diaphragm and enclosed within a larger cylinder which in turn is connected with the larger of the diaphragms.

Still another object of the invention is to produce a loud speaker which will produce two separate pitches of the same musical note simultaneously, the pitch variation of one being a harmonic of the vibrating frequency of the other cylinder.

Of course if the larger tube were not placed in vibration by the unit, the inner cylinderwhen in a state of vibration would cause the larger body to vibrate in the same period, which is known as consonance.

However, by employing two diaphragms of different angularity and of different area actuated by the same unit and by having two cylinders one within the other, not only may the high and low notes be more faithfully 45 reproduced, but the notes and their harmonies are produced simultaneously, thus adding richness of tone or timber to the reproducer.

With the above and other objects in view,

60 the invention consists in certain new and 1927. Serial No. 183,083.

novel arrangements and combination of parts, as will be hereinafter more fully described and pointed out in the claims.

Referring now to the drawings showing the preferred embodiment,

Fig. 1 is a prospective of my new reproducer or loud speaking unit,

Fig. 2 is a longitudinal sectional view of the same, and

Fig. 3 is a sectional view of the two diaphragms slightly spaced apart for the sake of clearness.

Referring now more particularly to the drawings, there is shown a base or support 1, which may be of wood or metal as desired, while at one end there is seen a vertical standard 2, to which there is secured the cross arm 3. As may be seen in Fig. 2, the standard 2 is slotted at its bottom as at l, and at its top as at 5, the standard being slightly enlarged at these two places.

There will also be noted a cylinder 6 that is supported at its outer end by a small stud or post 7, while the inner end of the cylinder is supported in the slots 4L and 5 in the standard heretofore mentioned.

This cylinder is preferably composed of a soft paper, which has very little grain and may be procured in the open market and is especially adapted for the manufacture of diaphragms or cones of the loud speaking units now in use.

In the present instance I have shown the cylinder having a length substantially twice its diameter and although the speaker as constructed by me has a length of a foot and a half, it may be made larger or smaller if so desired.

Located within one end of this cylinder, is the diaphragm 8 which is provided with the small flange or rim 9, and secured to the cylinder by glue or in any preferable manner. The diaphragm is conical in cross section and has its apex provided with a small opening 10 for the reception of the arm 11 that extends from the electrical reproducing unit 12.

This diaphragm 8 is also preferably formed of paper such as is used for the cylinder and is commonly used in the manufacture of cone speakers, although, if a metal diaphragm could be found of the right elasticity, it might equally well be used.

The electrical reproducing unit 12 of any Well known suitable type is fastened to the standard 2 and to the cross bars 3, while from binding posts on this unit 12 there is fragmentarily shown a cord 13 that will be connected to a radio set.

Now located within this outer cylinder 6 is the inner cylinder 14 also formed of paper, the area of this cylinder being two-thirds of that of the outer cylinder 6.

Fixedly secured to the inner end of this cylinder 14 is the paper diaphragm 15, its area being wo-thirds of the area of the diaphragm 8 so that its frequency vibration is substantially two-thirds of that of the larger diaphragm. The frequency variation is therefore one-third of the outer which causes the harmonic frequency between the two diaphragms. t will be understood that by changing the relative size of the inner cylinder and diapliragms, different ha monics might be produced which different harmonics might be desired under certain circumstances.

It will also be seen thatthe angularity of the larger diaphragm is substantially half of the angle of the inner diaphragm, so that the apices may contact and the remainder of the diaphragms spaced so that they are both free to vibrate throughout substantially their entire area.

A small button 16 is provided With the flange 17 and a further flange 18, while the inner end of the button is enlarged so that the apices of the diaphragms may be clamped about the button and the rod 11 will pass through the button and diaphragms and fasten to the button by the set screw 19.

Therefore the vibrations produced in the electrical unit will be transferredthrough the rod 11 to the two diaphragms to'actuate' them in the same manner that one is generally actuated.

The vibrations will be transmitted to the cylinders and the vibrations from the inner cylinder will also assist in setting into vibration the outer cylinder, and due to the areas of the cylinders a rather large mass of air will be set in motion. Due tothe size of the larger diaphragm and the cylinder, the larger cylinder will more faithfully reproduce the deep notes while the smaller cylinder and the smaller diaphragm will more faithfully reproduce the higher notes;

Due to the large ano small diaphragm-s therefore, both the high and the low notes are more faithfully reproduced than where one 7 diaphragm is used alone, and furthermore by correctly proportioning the size of the cylin ders and diaphragms not only are the note or notes reproduced but their harmonics are more clearly brought out, which as heretofore mentioned adds amplitude and timber or quality.

The intensity of the note depends of course on the extent of its vibrations and by having the large and small diaphragms both to be actuated instantaneously the intensity is greater than where simply one diaphragm is used. The pitch from the one diaphragm will be different from the pitch of the other, but they are arranged so that one will produce the harmonic.

It will be understood that a further number of harmonics might be produced by addfurther cylinders and further diaphragms of the proper dimensions.

From the foregoing it will be seen that I have invented a loud speaker which Will more faithfully reproduce all the audio frequencies of the musical scale and furthermore I have been able to supply the depth or colour to the reproduction; I can also more faithfully reproduce both the high notes and low notes and also reproduce notes with round or deep quality which has heretofore -een missing in most of the loud'speakers'in resent day use.

It will be understood that many slight chan es might be made without in any Way departing from the spirit and scope of the invention.

fiaving thus described my invention, what I claim as new and desire to secure by Letters Patent is:

1. A loud speaker comprising an actuating unit, supporting means for said unit, two diaphgramsphysically connected to a part of said unit, said diaphragms being of different areas and cylinders connected one to each of said diaphragms and the connection being such that the diaphragm andcylindcr in each instance are substantially integral.

2. A loud speaker comprising a base, an actuating unit two cylinders supported by said base and one within the other, vibratory diaphragms secured respectively in one end of each of said cylinders and physically connected with a portion of said actuating unit, the areas of the two diaphragms being in such proportion that the notes and their harmonics are simultaneously produced.

3. A loud speaker comprising two cylinders, one of which is substantially two thirds of the area of the other, one-of said cylinders being enclosed within the other of said cyl"- inders, a vibratory diaphragm fastened in an end of eachof's'aid cylinders, an actuating unit physically connected to both of saiddiaphragms and the areas of the respective diaphragms and cylinders being such that the notes and their first harmonic are simultaneously produced.

4. A sound reproducer comprising a base and two cylinders mounted thereon, one of said cylinders being substantially two-thirds in area of the other of said cylinders, a' vibratory conical diaphragm secured in each of said cylinders and each diaphragm located at the inner end of each cylinder, said diaphragms contacting at their apices, an actuating unit connected to said-diaphragms, the area of the smaller diaphra m and cylinder being substantially two-thir of the area of the larger diaphragm and cylinder, whereby notes and their harmonics will be simultaneously reproduced.

5. A loud speaker comprising two cylinders formed of suitable vibratory material, one of said cylinders being enclosed within the other and the one being substantially twothirds the area of the other, a conical diaphragm respectively secured in an end of each of said cylinders, the area of the one diaphragm also being substantially two-thirds of the area of the other, and actuating mechanism physically connected to both of said diaphragms and clamping the said diaphragms tightly together at their apices, the angularity of one diaphragm being substan tially one-half the angularity of the other diaphragm. H

6. A loud speaker comprising two cylinders of suitable vibratory material, one enclosed within the other, a base supporting said cylinders and a standard on said base and supporting an actuating unit, two diaphragms of different frequencies physically connected to said actuating unit and to their respective cylinders whereby the low and high notes may be more faithfully reproduced and the vibrations of the diaphragms will be transferred to the said cylinders and whereby the fundamentals and harmonics will also be produced on the actuation of the said diaphragms.

7. A loud speaker comprising an actuating means, two cone-shaped diaphragms of different frequencies physically connected to said actuating unit, the magnitude of the angle of one diaphragm being different from the other and the area of the one diaphragm being also different from the other and cylinders secured to the said diaphragms, one cylinder being positioned within the other.

8. A loud speaker for reproducing notes of high and low frequencies and for reproducing the primary and harmonics consisting of an actuating unit, a cylinder and a diaphragm therein and a second cylinder and diaphragm of substantially two-thirds the area of the first mentioned diaphragm and cylinder, the said diaphragms being substantially conical in shape and having their apices connected to each other and to the said actuating unit the said diaphragms and cylinders being formed of suitable sound-reproducing vibratory material.

9. A reproducer comprising an actuating unit, a plurality of conical diaphragms of difl erent areas and angularities, a plurality of tubes each of which is inherently fastened to one of said diaphragms, said diaphragms being physically connected together at their apices and to the said actuating unit in order that all of the diaphragms and tubes may vibrate simultaneously.

10. A reproducer comprising two tubular members of difierent diameters, each of said tubular members being closed at one end by a conical diaphragm, each of said diaphragms being of different angularity, an actuating unit, and each of said diaphragms being connected to each other and the said actuating unit.

11. A reproducer comprising a tubular member inherently closed at one end by a small cone, a similar tubular member of larger diameter and having a larger cone inherently closing the same, and one tube fitting within the other tube and cone, the said cones clamped together at their apices, and an actuating unit rigidly secured also to the two conical apices.

In testimony whereof I aflix my signature.

JAMES T. CORRIGAN.

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