US634575A - Telephone system. - Google Patents

Description

1 ,nventor.

3 Attorneyys Patented Oct. l0, I899.

E. W. HAM.

TELEPHONE SYSTEM.

(Application filed June 13, 1898.)

2 SheetsSheet (No Model.)

m: nomus urns co Witnesses.

Patented Oct. [0, I899.

E. W. HAM.

TELEPHONE SYSTEM.

(Application filed. June 13, 1898.)

2 Sheets-Sheet 2,

(No Model.)

n O t n e v n I Witnesses. -&M a umawm W Wu Att rneyvs.

a wing rricsi EDIVIN \V. HAM, OF IVOROESTER, MASSACHUSETTS, ASSIGNOR TO ILUMMER,

' HAM & RICHARDSON, OF SAMF PLACE.

TELEPHONE SYSTEM.

SPECIFICATION forming part of Letters Patent No. 634,575, dated October 10, 1899.,

Application filed June 13,1898. Serial No. 683,250. (No model.)

To all whom it may concern:

Be it known that I, EDWIN IV. HAM, a citi- Zen of the United States, residing at VVorcester, in the county of Worcester and State of Massachusetts, have invented a new and useful Telephone System, of which the following is a specification.

My invention relates to a system of intercommunicating or connected telephones; and the object of my invention is to provide a simple, efficient, and inexpensive form of switchboard which is light, compact, and durable, so that the same canbe readily mounted in the casing of an ordinary telephone instrument, and which will be positive in its action and not liable to get out of order.

To this end my invention consists of the parts and combinations of parts, as hereinafter described, and more particularly pointed out in the claims at the end of this specifica tion.

In the accompanying two sheets of drawings, Figure 1 is a transverse sectional view of a telephone-switchboard constructed according to my invention. Fig. 2 is a perspective rear view of a portion of the baseplate,showing the longitudinally-movable detent-plate mounted thereon. Fig. 3 is a partial sectional plan View. Fig. I is a partial sectional plan View taken at the other end of the switchboard, showing one of the circuitmaking plungers or push-buttons pushed into its operative position. Fig. 5 is a diagrammatic view illustrating the connections and circuits of a telephone instrument combined with a switchboard constructed according to my invention; and Fig. 6 is a partial plan View of one of the parts, which I term a bridgepiece, with the terminals which are secured thereon.

In'order to insure the successful working of the systems of intercommunicating or connected telephones which are now ordinarily employed, it is essential that any desired instrument of the system should be connected so that it can be readily called up from any one of the other instruments.

In some of the systems of intercommunieating or connected telephones which are now employed distinctive calls for the various instruments are sounded upon the call-bells,

One especial object which I have had in view in arranging the systems of intercommunieating telephones in connection with which myswitchboards are designed to be employed is to connect each instrument so that its call-bell will not be sounded except when connection is desired with that particular station.

In most of the systems of intercom m unicating telephones now used the instruments are connected by wires, which are bunched to gether or assembled in the form of a cable, two strands or wires being used for each instrument. In the use of switchboards in connection with telephone systems of this character it is essential that the connections should be accurately made by the switchboards without liability to short-circuiting or other disarrangement. It has also heretofore ordinarily been essential that after one of the instruments of. the system has been used the connections which were made in the switchboard for the purpose of connecting should be cut out and the switchboard restored to its normal position, as itis quite possible that if any one switchboard of the entire system should become disarranged or should be left in improper condition the entire system might be thrown out of working order, and in my application for patent filed April 22, 1897, Serial No. 633,326, I have shown and claimed a switchboard in which connections are made in a somewhat similar manner to that in which they are made in the switchboard herein illustrated; but in the construction shown in my aforesaid application for patent the circuit-making devices were intended to be automatically released and al lowed to return to their normal position by means of connections from the hook upon which the receiver of the telephone was to be hung.

A further especial object of my present invention is to arrange the telephone system so that it will not be necessary to release the circuit-making devices either automatically or otherwise when the use of the instrument is finished, and I have provided a form of switchboard which will retain any one of a series of circuit-making devices in its operative position until another one of the circuit-making devices is operated-that is to say, a telephone-switchboard constructed according to my invention comprises a plurality of normally open circuit-making devices and a detent mechanism for holding the circuit devices in their closed or operative position said parts being arranged so that when one circuit-making device is operated the circuitmaking device previouslyoperated will be released and allowed to assume its normal position. 1

In its preferred construction and as herein described my switchboard comprises a face-plate having a plurality of plungers or push-buttons movably mounted therein.

I have illustrated in the present case two rows or series of push-buttons; but the number or arrangement of course can be varied, as desired. Cooperating with a conical actuating-piece mounted on each plunger or push-button are a pair of spring-terminals or normally open contact-pieces, which tend to push the plunger back to its normal position. The plungers having conical operating-pieces to cooperate with normally open spring eontact-pieces operate in substantially the same manner as the corresponding parts shown in my application for patent before referred to, except that the relative position of the parts is reversed. Secured upon or forming part of each plunger or push-button is a steppingpiece having the shape of a double cone or double cam. Cooperating with the stoppingpieces of the several push-buttons of the switchboard herein illustrated is a l0ngitudinally-movable perforated s in'ing-pressed de tent-plate.

\Vhen anyone of the plungers or push-buttons of my switchboard is operated, the front incline of its conical stop-section will cam over or shift the movable detent-plate far enough to bring the edge of a perforation therein opposite the rearwardly-inclined conical or cam surface of the stopping-section of any plunger or push-button which may have been previously pushed in, so that said previously-omrated push-button will be free to be forced back under the pressure of th spring-terminals coacting therewith to its normal position. 'When the stopping-section of the plunger which is being pushed in has passed through the perforation of the detentplaie corresponding thereto, the detent-plate will be longitudinally shifted by its springs to hold the plunger in its operative position. Thus when any one push-button or plunger is operated the plunger or push-button which had been previously operated will be released and will be forced back, so that the electrical connections controlled thereby will be broken. By partially operating any one of the plungers, but not pushing the plunger in far enough, so that the detent-plate can engage behind its stop-section, a previously-operated plunger or push-button can be released without allowing the detent-plate to lock or socure the plunger being opera-ted in its forcedin position.

Referring to the drawings and in detail, 10 designates a face-plate or base-piece which is preferably made of hard rubber or other insulating material. Secured upon the back of the face-piece 10 are perforated bridgepieces 11, which are also preferably formed of hard rubber and are secured in place by means of screws 21, as shown most clearly in Figs. 3 and .4. Mounted in perforations in the face-plate 10 and bridge-pieces 11 are mov-' able plungers or p ush-puttons 11-, two rows of such push-buttons being illustrated herein, but the number of such push-buttons being capable of variation, as desired. Secured on the push-buttons 1lare conical operatingpieees 10, formed of insulating materiahas hard rubber.

Carried on the bridge-pieces ll and extending in position to cooperate with the operat ing-sections 16 are spring contact-pieces 12, which are insulated from each other, as shown in Fig. (3, and are arranged to cooperate with but are normally out of engagement with spring-lingers extending from plates 13, mounted on insulating-strips 18, as shown most clearly in Fig. 1.

Secured upon or forming part of the stem of each plunger or push-button is a steppingsection 17, having a chainfered or inclined rear edge.

The plungers or push-buttons 11- extend through perforations in a longitudinally-movable detent-plate 19, which normally tends to move in one direction under the influence of springs 20, as shown most elearlyin Fig. 2.

When a plunger or push-button is forced in, as shown in Fig. l, the detent-plate will be first shifted by the stoppingsection 17, and after the stopping-section of the plunger has passed the detent-plate 19 will spring back behind the stopping-section 17 and will hold the plunger 1 1- in its operativeposition. lVhenever another push-button is operated, the detent-plate 19 will be shifted far enough so that the edge of the perforation corresponding to the plunger or push-button previonsly operated will be brought opposite the chamfered part or incline forming the rear edge of the stopping-section of said p ush-button, leaving the push-button to be free to be restored to its normal position under the in fluence of its spring contact-strips 12. The same result may be accomplished by countersinking or chamfering the inside corners of the perforations in the detent-plate.

By partially operating any one push-but ten the other push-buttons which have been previously operated will be released from the control of the detent-plate 19.

The wiring or electrical connections between the parts of a telephone instrument employed in connection with a switchboard constructed according to my invention are illustrated diagrannnatically in Fig. 5. As

ITO

shown in this figure, A designates the switchboard, one pair of terminals to a of which are the terminals to which the line-wires from the cable S, corresponding with the telephone instrument, illustrated diagrammatically, are connected. B designates the call-bell of the instrument. 0 designates the generator or dynamo-electrical machine used for calling in the ordinary manner. a designates the calling-switch. D designates the battery; F, the induction-coil; G, the receiver; II, the receiverhook, and E the transmitter.- The wires connecting these several instrumentalities can be readily followed in said Fig. 5, and, as shown, the bell or calling-circuit of each instrument is normally in circuit with the line-wires corresponding therewith. In the operation of a telephone system as thus wired a subscriber whose call-bell sounds to reply to the call has simply to take down his telephone and push in the push-button or plunger corresponding to his own instrument, so as to connect the terminals to a to the bars 13 of the switch, which will throw the speaking and receiving circuits off the instrument onto the line-wires a a, so that one can then talk to the person who has switched his telephone onto the line-wires a a at any point in the system.

hen it is desired to send out a call from an instrument in a system of intercommunicating telephones constructed according to my invention, it is simply necessary to push in the desired push-button or plunger and send a call over the line by means of the callingswitch and generator in the ordinary manner, When a conversation has been ended, the person who has been called up and the subscriber making the call are not required to restore their switchboards to normal conditions, nor is it necessary that the switchboards should be automatically restored to normal condition, and thus by constructing the switchboards of an intercommunicating telephone system so that the operation of a circuit-making device will release the circuit-makin device which had been previously operated I am enabled to provide a simple, inexpensive, and positive system of telephonic intercommunication which will not readily get out of order and which requires no release of parts either automatically or by the persons using the system after a conversation has been finished.

I am aware that changes may be made in the construction of my switchboard for telephone systems by those who are skilled in the art, and I do not wish, therefore, to be limited to the construction or to the particular arrangement of connections which I have herein shown and described; but

lVhat I do claim, and desire to secure by Letters Patent of the United States, is-

1. In a telephone-switchboard, the combination of a plurality of circuit-making plungers or push-buttons, each having an inclined stopsection, and a longitudinally-movable detentplate cooperatin g with said push-buttons, the engaging surfaces of the push-buttons and the detent-plate being chamfered or inclined in the opposite direction to the stopping-section of said push-buttons, whereby when a p ush-button is operated, previously-operated push-buttons will be released before the pushbutton being operated comes to its operative position, substantially as described.

2. In atelephone-switchboard, the combination of a plurality of push-buttons or plungers, each having a conical operating-section, two spring-arms engaging the conical section of each plunger to normally force said plungers outwardly, a contact-piece cooperating with each spring-arm, whereby each plunger is adapted to make two electrical connections when pushed in, a conical stop-section carried by each plunger, and a perforated longitudinally-movable detent-plate cooperating with said plungers, one or both of the engaging edges of the detent-plate, and the stop-section of each plunger being chamfered or inclined in the opposite direction to the incline of the stop-section, whereby previously-operated plungers will be released and allowed to assume their normal positions before the plunger being operated comes to its operative position, substantially as described.

In a telephone-switchboard, the combination of a face-plate 10, a plurality of springpressed plungers 14 mounted therein, each plunger having a cam-operating section 16, and a double cone, stopping-section 17, a pair of normally-open, spring contact-arms 12 cooperating with and engaging the operatingsection 16 of each plunger and normally tending to force each plunger outwardly, and a longitudinally-movable detent-plate 19 having springs 20 connected thereto, so that said detent-plate will tend to engage behind the stoppingsection of each plunger when the same is pushed in, substantially as described.

In testimony whereof I have hereunto set my hand in the presence of two subscribing witnesses.

EDWIN W. HAN.

Witnesses:

PHILIP W. Sourncarn, Louis W. Sournoirrn.

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