US1340471A - Vibratory-diaphragm controller - Google Patents

Description

M. l. WILLIAMSON. Y VIBRATORY DIAPHRAGM CONTROLLER.

APPucATlou FILED MAY 13. 1919.

1,340,471, Patented May 1s, 1920.

MEDIUM MARSHALL I. WILLIAMSON, oF BALTIMORE, MARYLAND.

VIBRATORY-DIAPHRAGM CONTROLLER.

To all whom t may concern:

Be it known that I, MARSHALL I. WILLIAM- i soN, a citizen of the United States, residing of producing or reproducing sound or not,.

the object of the invention being to provide an improved means for controlling the vibrations of the diaphragme in such instruments.

A further object of theinvention is to provide a controlling means of the character set forth,.which is entirely independent of the elements or forces which produce the vibrations of the diaphragms.

.A further object of the invention is to provide a controlling means of the character set forth, which is extremely simple in construction, economical to manufacture and highly eiiicient in operation.

With the foregoing and other objects in view, which will appear as the'description proceeds, the invention consists in the novel features of construction and combination of parts which will be more fully described hereinafter and particularly pointed out in the claim. A

Through experimental work and study I have discovered that while slight pressure, often in fact mere contact at' or about the center of a vibrating diaphragm renders it for the time either nearly or completely inactive, pressure near lthe edge of the diations by pressure on the diaphragm and so 5 5 produce regulating and maintaining such ressure that an arbitrary control; over t e diaphragms vibrations may be accomplished which in the case of sound producing instruments or machines would result ina correspondin control over the volume of sounds Specification of Letters Patent.

. Patented May 1S, 1920.

Application ledfMay 13, 1919. Serial No. $6,769.

In the drawings accompanying and forming a part of this specification. i

Figure l is a side view, Apartly in section, of a sound-receiving instrument having my improved controller applied thereto, the instrument being broken away at the rear thereof; n

Fig. 2 is a front end elevation thereof; and

Fig. 3'is a perspective view of a flexible pad forming one of the essential 'parts of the present invention.

The same characters of reference designate the same parts inthe several different figures of the drawings.

Referring to the drawings, 2 designates an ordinary telephone receiver having the usual coils 3 and magnetic. vibrators 4, and the usual diaphragm 5 which vibrates in response to the fluctuating magnetic force of the vibrators 4, the coils and vibrators being mounted in a housing 6 of bell shape and on the outer end of which the diaphragm is seated and clamped thereto by means of a shoulder 7 carried by an annular member or at its outer end, and the space between the.

shoulder 7 and the shoulder 9 is threaded for cooperation with a cap or-ear piece 10.

. An annular or washer-like pad 1l of flex-- 1ble material, such for instance as cork,

felt, rubber, paper or other suitable material is mounted within the circumferential shoulder i and is held centrally there-A within by engagement with the cap. 10. When not under pressure the pad contacts only at its eXtreme outer circumferential edge with the diaphragm, its inner side being inclined slightly, as shown, from its outer toward its inner circumference, while its outer side is flat and is adapted to be engaged by the cap 10. By this construction it will be seen that by rotating the 4cap so as to press with greater force on the pad, the latter will be forced into greater contact with the diaphra m from the outer cirmcumference thereo' toward the center and that in such manner the vibrations of the diaphragm may be controlled to any desired extent. For example, when it is desired to produce the maximum volume of sound the cap 10 is rotated'so as to move it away from the pad thus lessening the latters contact and pressure upon the diadiaphragm until, if the pad is wide i phragm, while when the minimum volume is desired it is rotated so as to carry it toward the pad to the extreme of its inward movement thereby increasing the contact and pressure of the pad upon the diaphragm. I" other words, when the cap is moved outwardly as described the pad gradually assumes its normal shape thus gradually lessening its contact with the diaphragm and increasing the vibrating area of the latter until at the extreme outward movement of the cap, which is determined by the shoulder 9, the only contact of the pad with the diaphragm is 'at the extreme circumference of both, in which position the pad offers least resistance to the full activity of the diaphragm thus permitting the full volume of sound whereas when the cap moved inwardly, it gradually com4 presses the pad so that its contact with the diaphragm is gradita ly increased from its outer circumference inward J- thus gradually decreasing the vibrating area of the enough complete inaction of the diaphragm is accomplished and thus the complete absence of sound.

The front of the annular member or ring 8 may be provided with designations, such as Loud, lt/iedium'" and Soft, and the outer face of the cap 1U with an arrow or similar mark for indicating` the proper relation between the cap and ring to produce the volume of sound desired. The edge of the cap may be roughened7 as shown at l2, to provide a grip to assist in turning the cap'. The inner face ofthe pad is preferably scored as shown at 13 to prevent it adhering to the diaphragm after pressure has been withdrawn. The outer surface of the pad should be substantially stiffened so that it will remain always flat against the cap; in fact it may befound desirable to ralenti have the entire out-er surface of the pad securely fastened to the cap so as to prevent accidental or undesired shifting or change of position.'

lWhile I have described in detail the structure herein illustrated, it will be understood that I donot thereby limit my invention to the .precise features of construction shown, as l am aware that many mechanical changes and modifications may be made therein without departing from the spirit and scope of the invention as set forth in the claim hereto appended.

Having thus described my invention, what l claim is:

lin a telephone receiver, a housing, a vibratory diaphragm seating on the outer end of the housing, an ear piece over the diaphragm, a ring carried by said end of the housing and having an internal shoulder engage-able with the diaphragm adjacent to its periphery for clamping the .saine to the housing end, said ring also having a second internal shoulder and being internally screw threaded between said shoulder and the firstmentioned shoulder, the aforesaid ear piece haring a rear portion which is screwed into the aforesaid threaded portion of the ring and is adjustable between the shoulders, and an annular member between the diaphragm and the ear piece and engageable with the former adjacent to its periphery, said ear piece being adjustable to force the aforesaid member into contact with the diaphragm to a greater. or less extent radially thereof, thereby to vary the diameter of the vibratory portion of the diaphragm.

ln testimony whereof I aHiX my signature in the presence of two witnesses.

MARSHALL l. VILLIAMSON.

Witnesses:

E. AVALTON BREWINGTON, HOWARD D. ADAMS.

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