US292335A

US292335A - Magneto-electric telephone

Info

Publication number: US292335A
Authority: US
Publication date: 1884-01-22
Anticipated expiration: 1901-01-22

Description

(No'ModelJ' u 2 Sheets-Sheet 1.

T. D. LOCKWOOD 8; T. W.- LANE.

MAGNET() ELECTRIC TELEPHONE.

` (No Modem '4 2 s-heets-sneet-z..

` TLD. 'LooKWooD s; T.'W'. LANE] MAGNBTO ELBCTRIGTE-LBPHONE.; l No. 2925335. Patented Jan. 22 1884:.

LINE our.

h5 I LINEl -IN' W/inels es,

UNITED STATES THOMAS D. LocKwooD, 'or

MALDEN, MASSACHUSETTS.

PATENT OFFICE.

AND THOMAS V. LANE, OF BOSTON,

l SPECIFICATION forming part of Letters Patent No. 292,335, dated January 22, 1884. l Application filed July 28, 1883. (No modell i To @ZZ wil/omit may concern:

Be itknown that we, THOMAS D. LooKwooD, -of Malden, in the county of Middlesex and Stated-Massachusetts, andTHoMAs W. LANE, 5 o f Boston, county of Suffolk, and State of Massachusetts, have invented a new and useful Improvement in Magneto-Electric Teleph on es,

which improvement is fully set forth in following specication.

This invention has reference to that class of articulating telephones commonly employed as receivers, but capable of use as transmitters as well, which .comprise avibratory magn'etic diaphragm, or vibratory diaphragm and I5 armature, and a permanent magnet, with a spool or bobbin of insulated wire on one or both poles 5 and it consists inthe combination, with the permanent magnet of such an instrument, of an additional Spool or bobbin,

2o which maybe included in circuit with an'electric battery for intensifying and maintaining the magnetism, said additional spool or bobbin being placed on the same pole with the v usual spool or bobbin of the telephone.

25 It also consists in 'the arrangement of said two spools or bobbins on thesame soft-iron pole-piece or polepieces,and in close proximity tov each other, the re-enforcing bobbin or f spoolbeing preferably on the inside between `3o the ordinary spool, (which is included in the telephone-circuit or line-wire,) the object being to make the instrument as small and compact as maybe (thepole-pieces being smaller than the body ofthe weight) and as effective. -It further-comprises the combination, with the instrument having the two bobbins, spools, or coils, and the battery-circuit including one of said-bobbins, spools, or coils, of aswitch for breaking the said circuit when the -instru- A 4, a similar diagram, showing an instrument witha bar-magnet; Fig. 5, a side view, partly in section, of a hand-telephone constructed in accordance with the invention; Fig. 6, a dia- 55 gram showing a switch for breaking the battery-circuit when the instrument is not in use; Fig. 7, a diagram illustrating a portion of a switch-board, with a connector and circuits adopted for use with the improvedinstru- 6o ment; and Fig. 8, a diagram of the connections when the transmitting-battery is utilize'd.

A is the mouth or ear piece; B, the inclosing-case; C, Figs. 1 and 2, a bracket; D, the 65 vibratory diaphragm of magnetic materialsuch as soft iron; and M, thepermanent magnet, preferably of steel. Referring to Fig. l, the magnet M is bent so that there are at theV ends projections d d.' In theseV projections 7o the inner ends of the soft-iron pole-pieces c c are Xed. The re-enforcing bobbins, spools, or coils b bV are placed on the pole-pieces at the inner end thereof. The other or ordinary bobbins, a a', are placedon the same pole- 75 pieces at the outer end. The pole-pieces or cores of the bobbins are bent so that the ends of the bobbins a c face the diaphragm D, while the bobbins b b present their sides to it.

The'bracket C on the back of the instru- 8o ment is for fastening it to an arm or rod, which passes through the core @,the set-screw f retaining the instrument in place and permitting it to be adjusted when desired.

The bobbins or re-enforcing coil-sb b are in- 8 5 eluded in the vcircuit of an electric generator or galvanic battery, 7c, and the connections are so vmade that the electro-magnetism created by the galvanic current increases and maintainsthe magnetism of the magnet. The bob- 9o bins a a are connected to line in any ordinary way. The binding-posts forming connections with the exterior conductors are lettered g h fijinFigz2. ,ffy

Although the circuit of battery 7c may be 95 constantly closed, practically this wouldv in- 'volve a Waste of electric energy, and-therefore switches for breaking the battery-cir'cu it would be'employed. The arrangement of these'is described below. f

In Figs. 4, 5, 6, the bar-magnet Mhas only one pole-piece, c, which forms a core to both -Ioo bobbins, spools, or coils a and b. As before, the re-enforcing bobbin b is nearest the magnet; the bobbin a nearest the diaphragm D.

1, 2, 3, and 4, Figs. 4 and 5, are the binding-posts. The battery k is in eluded in a loop between the posts 2 and 3. In Fig. G there are only three binding-posts, 1, 2, and 3, the post 3 being connected by the wire m. with the bobbin or coil b, and by the wire Z with the bobbin c. The post 2 is connected by wire m with the other terminal of the coil or bobbin I); the post 1 by the wire Z with the like terminal ofthe bobbin a. In this gure the circuit of the battery l; is broken, and the two terminals are connected with the contact-plates 5 and 6, respectively, which are insulated from each other. The switch-leverp ofthe ordinary gravity-switch connects together the two plates when relieved of the weight of the telephone, so that the circuit of the battery l: through the bobbin or coil b is complete only when the telephone is in use. \\`hen the transmitterbattery is used to increase and maintain the magnetism of the receiver, the connections are as shown in Fig. S. The circuit of the battery k includes the contact-plates 5 6, bindingpost 3, re-eni'oreing bobbin or coil b, bindingpost 2, primary ot' induction-coil 9, and transmitter 10. rlhc telephone-circuit or main line is divided, one branch passing from the contact-plate 6, binding-post 3, principal bobbin or coil of the telephone-receiver a, bindingpost 1, and secondary of induction-coil to line or ground; the other from the contact 7, through signal-bell 8, to line out or ground.

Vhen the telephone is suspended from the switch-lever p, as shown, the circuit of battery It is broken, andthe signal-bell 8 only is in circuit. Then the telephone is removed, the battery-circuit is closed by the switch p between the contact-plates 5 and 6, and the main line is completed through the telephone-rcceiver and the secondary of the induction-coil. For use at the central oiice or at other points a plug, P, is provided. This plug is divided into four parts, which, as they are connected, respectively, with the binding-posts 1, 2, 3, and 4, are correspondingly marked 1', 2', 3', 4. For convenience ot' illustration the plug is shown partly in cross-section. The plug is inserted in the opening between the plates 12 and 13, 14 and 15, so that the posts l and 4 are connected with the plates 12 and 13, respectively, and the bobbin c (of Figs. 4, 5, and 6) or bobbins c a (of Figs. 1 and 3) are included in the line-circuit, while the posts 2 and 3 are connected with the plates 14 and 15, respectively, and are thus included in the local circuit or battery k. It is obvious that a number of lines may center in a switch -board provided with a set of'plates-sueh as 12, 13, 14, and 15-for each line-circuit; also, that a single battery may be connected with several pairs of plates, 14 and 15.

The details of construction may be greatly modified without departing from the spirit of the invention, and portions ofthe invention may be used separately. For example, the particular switches shown need not be employed; but other known and suitable systems 7o may be adopted to use with the improved instrument.

Although it is preferred to have the two bobbins or two sets ot' bobbins on the same end or ends of the magnets and on pole-pieces smaller than the body of said magnets, and although this construetionis speciallyclaimed, yet it is obvious that one or more bobbins placed at other parts of the magnet could be used to intensiyand maintain the magnetism 8o thereof.

\Ve claim- 1. The combination, with a telephone comprising a permanent magnet and two coils or bobbins placed on the same pole of the magnet, of a lbattery included in circuit with one of said coils or bobbins, so as to increase the magnetism of said magnet, the other coil or bobbin being included in the telephone circuit or line, substantially as described. 9o

2. The telephone having the two coils or bobbins, or two sets of coils or bobbins, placed on the same pole-piece or pole-pieces of the permanent magnet, in combination with an exciting-circuit including. a battery and one coil or bobbin, or one set of coils or bobbins, so that the current intensifies and maintains the magnetism of the magnet, and the telephone circuit or line including the other coil or set of coils, substantially as described. ioo

3. Atelephonc comprising, in combination with the diaphragm, permanent magnet with one or more pole-pieces, and a bobbin at the end of each pole-piece, a second bobbin placed on each pole-piece inside thefirst-named bobbin, between it and the end of the body of the magnet, substantially as described.

4. The combination, with a telephone having a magnet and two bobbins or coils, 011e included in circuit with a battery, so as to in- 11o tensify and maintain the magnetism, and the other in the telephone-circuit, of a key for opening said battery-circuit when the telephone is not in use, and closing it when the instrumentis to be used, substantially as described.

5. The combination, with a transmitter and its battery, of a telephone comprising a magnet with two coils or sets of coils, one included in the circuit of said battery, and the otherin 12o the telephonefcireuit, and a switch for opening the battery-circuit when the instruments are not in use, substantially as described.

In testimony whereof we have signedv this speciiication in the presence of two subscribing witnesses.

THOS. D. LOCKVOOD. THOMAS \V. LANE.

XVitnesses:

GEO. XVILLIs Pinnen, D. E. Rica-inns.