US1485196A

US1485196A - Telephone transmitter

Info

Publication number: US1485196A
Application number: US494770A
Authority: US
Inventors: Murray Robert Lambert
Original assignee: Telephone Manufacturing Co Ltd
Current assignee: Telephone Manufacturing Co Ltd
Priority date: 1921-08-24
Filing date: 1921-08-24
Publication date: 1924-02-26
Anticipated expiration: 1941-02-26

Description

Feb. 26, 1924.- 1,485,196

R. L. MURRAY TELEPHONE TRANSMITTER Filed Auz. 24 1921 I Inventor @wgmw Amit mean ries.

ROBERT LAMBERT MURRAY, OF BUSHEY HEATH, ENGLAND, ASSIGNOR TO TELEPHONE MANUFACTURING COMPANY LIMITED, 01 LONDON, ENGLAND.

TELEPHONE TRANSMITTER.

Application flled- August 24, 1921'. Serial No. 494,770.

To all whom it may concern:

Be it known that I, Ronnn'r LAMBERT MURRAY, .a subject of the King'of England, residing in Bushey Heath, Hertfordshire, England, have invented certain new and useful Improvements in Telephone Transmitters, of which the following is a specification.

This invention relates to telephone transmitters of that type of which the diaphragm or a pad thereon is intended to be held in contact with a surface of portion of the users erson, hereinafter referred to in a genera sense as the throat -in contradistinction to the type intended to be held near the mouth to receive sound transmitted through the air. The term pad is intended to denote any projection carried upon the diaphragm itself so as to be interposed between the diaphragm and the surface against which it is to be pressed so that vibrations are transmitted mechanically through the said projection. v

The object of the present invention is partly to prevent undue pressure being exerted between the diaphragm or pad and the users throat and partly to provide a construction by which the transmitter shall be less liable to displacement from a convenient position than has heretofore been the case.

The present invention therefore provides a telephone transmitter of the type described provided with one or more members carried by the diaphragm-support and extending therefrom to bear upon the sun face of the users person around or closely adjacent to the surface upon which the diaphragm or a pad thereon presses. v

Conveniently, according to this invention, a telephone transmitter of the'type described is provided with a rigid or other shield carried by-the diaphragm support, apertured to permit the diaphragm or a pad thereon to project through the aperture and shaped or dimensioned to bear upon the users throat surrounding or closely adjacent to that part thereof against which the pad is pressed.

Preferably, according to this invention, a telephone transmitter of the type described is provided with a shield of elongated form (for example of elliptical form) centrally apertured to clear the diaphragm and so carried by the diaphragm-support as to permit the diaphragm to project beyond the (not securing rin shield and that the longer dimension of the shield extends in the direction of the length of the users neck when in use.

The accompanying drawings illustrate, by way of example only, two embodiments ofthe present invention which give good results,

Figure 1 being a pers ective view ofone form of telephone havlng a throat-transmitter embodying the present invention,

Figure 2 a sectional view taken vertically through the centre of Figure 1, and

Figure 3 a side view of a telephone handset embodying the invention, having part of the transmitter broken away to reveal its construction.

Referring first to Figure 2, the transmitter 1 is built together with a receiver 2, upon a foundation ring 3 common to them both. The receiver magnet 4 is encircled by the ring and is mounted upon a base-plate 5 which serves to close one otherwise open side of the ring, and the other open side is closed by the receiver diaphragm 6 which is covered by a dished flanged cap 7, whereof the flange 8 surrounds the ring and is socured to the latter by screws 9. The concavity of the cap is towards the diaphragm 6 and a duct 10 leads from the chamber 11 thus formed between the diaphragm and the cap through the tubes 12 to the ear pieces shown).

On the exposed side of the base-plate, that is to say the side opposite to that which carries the receiver magnet, the transmitter is mounted. The transmitter is provided with a diaphragm 13 to which is secured a cup 14 in which carbon pellets are received and retained and with a contact plate 15 for the carbon pellets, which plate is secured to the base-plate 5 by a screw. The diaphragm is held in position by a flanged 16 whereof the flange 17 engages the dlaphragm 13 and the body is secured to the foundation ring 3 in any convenient manner. The .said securing ring carries an elliptical larynx shield 18 of ebonite havin a. circular central aperture 19 to allow t e transmitter diaphragm to protrude slightly therethrough. The said securing ring is provided with two diametrically opposite gaps 21' which receive and engage lateralprojections 22 upon the base-plate, which pro'ections are intended to receive the attaching straps, indicated in chain lines-at 23 whereby the whole .de-.

vice is held in position upon the, users throat. The longer axis of the shield hes transversely across the line'of the attaching" straps, that is in the plane of the face of the section shown in Figure 2.

{-When in use the larynx shield serves to' prevent the pressure of theattaching'str'aps from being entirely transmitted through the "diaphragm tothe' larynx and divertspart of this pressure to the surrounding muscles thereby relieving'the pressure on the laryi 1x and in some measure predetermming. its

magnitude. a

The shield, moreover, enables the dia'- phragm to be kept properly presented to the throat with less pressure than-was hereto-- fore required since without the shield the weight of the device constantly tended to make it tilt outwardly about its lower edge with the result that the lower portion of the diaphragm alone remained in contact with the throat, unless an inconveniently large pressure was maintained by the attaching straps; the downwardly projecting portion of the shield afi'ords a-betterleverage -for the attaching straps enabling-the diaphragm to be held againstthe throat with less tension in the straps. It is also found that by this means the transmitter is less liable to displacement from its correctlocation upon the throat,. which location appears to be a slight depression, or at least a part occupied with relatively softer tissues, lying between two muscles, tendons or other relatively harder structure of the neck-of the user. The shield may also serve to aid in transmitting from the throat to the microphone.

In Figure 3 is shown a handsetof the usual type in which a rigid tube 24 supports a receiver 25 secured bv a screw 26 at one end and a transmitter 27 at the other end and has a hand-grip 28 provided about its middle. The transmitter, however, is of the kind hereinbefore described as for application to the outside of a users throat. It comprises a diaphragm 29 carrying the pellet-cup 30, and a dished plate-31carry-v ing the pellet contact 32, the plate and the diaphragm being held together at their edges in any suitable manner.

These transmitter parts are held in position against the forward extremity of a cup-shaped casing 33 by a larynx shield 34 of vulcanite or similar substance of-which an inwardly directed flange 35 engages a cooperating outwardly directed edge 36- of resales tral aperturethrough-w-hich the diaphragm I 29'slightly protrudes, the aperture being of such diameter that it is clear, of the protruding portion of the diaphragm.

If desired, the receiver of this hand set ma be permitted a certain-amount of pivota movement about its'securing screw 26 So that it can be properly seated against the users ear notwithstanding the angle at which the supporting tube may. have to be held inorder to bring the diaphragm into full contact with the usersthroat.

This construction obviously is particularly suitable for use in circumstances in which a throat-transmitter isdesirable, but.

in which it is not desired to have the mstrument secured about one particular users head.

It will be" appreciated that the aforesaid shields are not the only forms of shield which will fall within the scope of this invention. For example, oppositely. projecting lateral arms of resilient material may be employed and thesemay be two in number, one on either side, on more, and their free ends may be provided with pads or not,as desired. T What I claim as my invention and desire to secure by Letters Patent is 1. In a telephone transmittenthe combination of a support, a microphone carried thereby, vibration-transmitting means oper-' atively connected with the mlcrophone for directly receiving sound-vibrations from a part 0 the. human body and for transmitting the same to' the microphone, and pressure-distributing means carried by the su port and 'spaced radially away from t e margin. {of said 'vibration-transmitting means, which latter means extends axially in front of the pressure-distributing means whereof the front face is situated so farrearwardly of the front face of saidvibra-' tion-transmitting means as to constitute a pressure-distributing support for the transmitter when thefront face of the vibrationtransmitting means bears against a part of the human body, substantially as described.

2. In a telephone transmitter, the combinationof a support, a diaphragm arranged to receive directly sound-vibrations from a part of the human body, a micro hone op eratively connected with said diaphragm and mounted between the same and said support, and a shield that constitutes the sole means for holding said diaphragm and said-micro hone in position on thesupport which shie d isearried by the support and has an aperture through which said diamemes phragm extends axially, with marginal clearance, beyond the front face of the shield, which front face is situated so far rearwardly of the front face of said diaphragm as to constitute a pressure-distributing support for the transmitter when the front face of the diaphragm bears against a part of the human body, substantially as described.

3. In a telephone transmitter, the combination of a support, a diaphragm arranged to receive directly sound-vibrations from a part of the human body and having an outwardly-directed flange, a microphone 0per-.

atively connected with said diaphragm and mounted between the same and said support, and a centrally apertured shield of elliptical form carried by said support and engaging said flange and thereby holding said diaphragm and said microphone in position on said support, which shield has its front face situated so far rearWardly of the front face of said diaphragm as to constitute a pressure-distributing support when the front face of the diaphragm bears against a part of the human body, substantially as described.

In testimony whereof I have signed my name to this specification in the presence of two subscribing Witnesses.

ROBERT LAMBERT MURRAY.

Witnesses:

L. E. GREENACRE, T. J. OSMAN.