US 579239 A
Description (OCR text may contain errors)
M mg Ire raras WILLIAM o. MEIssNnR, or cIIIci-ieo,
ILLINOIS, ASSIGNOR TO THE AMERI- TELEPHONE SPRING-JACK.
SPECIFICATION forming' part of Letters Patent No. 579,239, dated March 23, 1897. Application led January 17, 1896- Serial No. 575,919. (No model.)
.To all whom t may concern.-
Be it known that I, WILLIAM O. MmssNnr., a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Telephone Spring-Jacks, of which the following is a speciiication.
My invention relates to telephone springjacks, and has for its object to provide a new and improved spring-jack, of which the following is a description, reference being had to the accompanying drawings, wherein- Figure l is a longitudinal section through a sprin g-j ack embodying my invention. Fig. 2 is a view of the same with the parts differently disposed. Fig. 3 is a diagram of a telephone system having two subscribers and provided with Inyimproved spring-j ack. Fig. a shows a modified form of spring-jack to be usedupon a system that has no ground return.
Like letters refer to like parts throughout the several figures.
As illustrated in the drawings, my device consists of the plate A, of insulating material, having the different parts associated therewith. At one end of the plate A is an upwardly-projecting piece A', also of insulating material, and provided with an opening through which is inserted the pin B. Said pin is made of insulating material and has its outer end B beveled. or cone-shaped, as shown. Extending through the pin B is a metallic rod B2, which projects beyond the beveled end of the pin, as shown. Ahandle B2 is connected with the pin B and is provided with a conductor B4, which is electrically connected with the rod B2. A stationary contact A2 is connected with the plate A and is so positioned that it is engaged by the pin B when said pin is inserted through the hole in the part A. This contact may be of any suitable description and, as shown, consists of a hollow tube through which the pin is adapted to be inserted. The contact A2 is electrically connected with the conductor A2,which is connected by wire A4 to one terminal of the circuit.
Connected with the plate A is a spring-contact C, provided with the projecting part C', adapted to engage the rod B2, said springcontact being connected with the circuit by means of the wire C2. The projecting part C maybe made in any suitable manner. As herein shown it is made by bending the springcontact downwardly, so as to form a V-shaped projection. The free end of the spring-contact C is interposed between the stationary contacts A2 and C3, the contact C2 adapted to be connected in circuit by the wire C4.
The outer end of the pin B is beveled, as shown, as is also the projection C', the beveled surfaces on the projection and pin engaging each other when the pin is in position. The handle B2 is so shaped as to engage the part A', so as to limit the inward motion of the pin B, and the parts are so positioned thatwhen the end of the pin is in contact withthe projection C' on the spring-contact C the pin may still be moved a short distance inwardly before being stopped by the engagement of said handle with the upwardly-projecting part A'.
Vhen the pin B is removed from its socket, the spring-contact C isin contact with the stationary contact A2. When the pin is inserted and is in the position shown in Fig. l, said spring-contact is moved out of contact with the contact A2 and in contact with the rod B2 in the end of the pin B. If, now, the pin is moved inwardly to the position shown in Fig. 2, the beveled end of the pin B engaging the beveled surfaces of the projection C moves the spring-contact C to the position shown in Fig. 2, Where it is in contact with the stationary contact C3.
As the pin Bis of insulating material there will be no contact with the circuit leading from said pin. When the pin is moved to the position shown in Fig. 2 and then released, it is automatically moved back to the position shown in Fig. l on account of the engagement of the beveled surfaces on the projection C and the pin B.
I have shown diagrammatically in Fig. 2 a telephone system of two subscribers containing myspring-jack or circuit-changing device. The instrument C5 of one subscriberis connected to the ground at C and to the spring-contact C, said contact being normally connected with the stationary contact A2, which is connected through the annunciator C7 with the ground at CS. The stationary IOO contact C2 is connected by wire C4 with the generator E,which generates the current used in signaling. The conducting part B2 of the pin B is connected by wire B4 with a second pin B9, and is also connected with the contact B5, operated by the key B6, and opposed to the contact B7, connected with the opcrators instrument B2. The instrument F of the second subscriber is connected up in a manner similar to that of the instrument C5 of the first subscriber. When the parts are in the position shown in Fig. 3 and the subscriber having the instrument C5 calls up, the circuit will be as follows: from ground C6 through the instrument C5 and wire C2 to contact C, thence through contact A2, wire A4, annunciator C7 to ground C8. The annunciator shows the central operator that the subscriber is calling, and the pin B is inserted in the contact A2, the parts taking the position shown in Fig. 1. The key B6 is then depressed, bringing the contact B5 into contact with contact B7. This places the operators instrument B8 in circuit with the subscribers instrument C5, so that the number wanted may be made known to the operator. The pin B9 is then inserted into the stationary contact A2, associated with the instrument F in this case, and is moved to the position shown in Fig. 2, so as to connect the spring-contact C with the stationary contact C3. The circuit will then be as follows: from generator E to contact G3, associated with the instrument F, thence through spring-contact C, thence by wire C2 through the signaling device of the instrument F, thence to the ground C6, and thence back to the generator. The signal of the subscriber having the instrument F will then be operated. IVhen the pin B9 is released, it is automatically moved to the position shown in Fig. l and the two instruments F and C5 are in circuit, so that the two subscribers may communicate with each other.
I have only shown a system with two subscribers, as such a system will illustrate my invention, but it is of course evident that it may be applied to a system containing any number of subscribers. I have also only shown a grounded system, but my invention is applicable to a system having a metallic circuit. In this event the spring-contact C is connected to one branch of the talkingcircuit and the stationary contact A2 with the other branch.
I have illustrated in Fig. et a circuit-changing device as modified for use with a metallic circuit. The operation of this device is similar to the operation of the circuit-changer when used on a grounded system, the only difference being that there must be two circuit connections instead of one. I obtain this by connecting a conducting-piece G to the pin B, so as to make contact with the stationary contact A2, said conducting-piece being connected by wire with a similar conductingpiece on a second pin. A spring or movable contact G is associated with the stationary contact A2 and is adapted to be brought into contact therewith by engagement with the handle B3 when the pin B is moved to its eX- treme forward limit. It will be seen that by this construction the signaling device of any subscriber is easily and quickly operated without operating the signaling device of the other subscriber or without in any way affecting his instruments, said latter subscriber being entirely disconnected from the generator supplying the signaling-current. I have described these several parts in detail, but it is evident that they may be greatly changed in form, construction, and arrangement without departing from the spirit of my invention, and I therefore do not wish to be limited to the construction shown.
I claiml. A circuit-changing device comprising a spring-contact interposed between two stationary contacts and normally in contact with one of said contacts, a contact-pin composed in part of conducting material, said pin adapted when interposed between said springcontact and one of said stationary contacts to separate said contacts and connect the springcontact with the conducting part of the pin, said pin so constructed that when moved to a predetermined position said spring-contact is moved out of contact with the conducting part thereof and into contact with said second stationary Contact.
2. A circuit-changing device comprising a spring-contact interposed between two stationary contac ts and normally in contact with one of said contacts, a contact-pin composed in part of conducting material, said pin adapted when interposed between said springcontact and one of said stationary contacts to separate said contacts and connect the spring-contact with the conducting part of the pin, said pin so constructed that when moved to a predetermined position said spring-contact is moved out of contact with the conducting part thereof and into contact with said second stationary contact, the opposed contact-surfaces onsaid pin and spring-contact so shaped that said pin is automatically moved when released so as to be electrically connected with said spring-contact.
3. A circuit-changing device comprising a spring-contact interposed between two stationary contacts and normally in contact with one of said contacts, a pin of insulating material having a conductor projecting from the end thereof and adapted when inserted between said spring-contact and one of said stationary contacts to engage said spring-contact and move it out of contact with its opposed contact, said insulating-pin provided with an inclined surface adapted to be brought into engagement with an inclined surface on said spring-contact by a further movement of said pin so as to move said spring-contact an d disconnect it from the conductor projecting from the pin, at the same time connecting it with said second stationary contact, and a IOO IIO
device for limiting,` the further movement of said pin so that when released it is automatically moved so as to disconnect the springcontact, and a second station ary contact, connectiug said spring contact with the conductor projecting' from the end of the pin.
4. A circuit-changing device comprising a spring-contact interposed betweenl two stationary contacts, an insulating-pin provided at one end with a device adapted to limit its inward movement, and at the other end with a conductorl adapted to engage said springcontact when the pin is in a predetermined position, said insulating-pin provided with an inclined surface opposed to a V-shaped projection on the spring-contact so as to engage the same when said pin is moved to the limit of its inward movement, substantially as described.
5. A Circuitbhanging device for telephoneexchanges comprising a series of stationary contacts connected with the signaling-generator, a second series of stationary contacts, each connected with one branch of the talking-circuit of a subscriber, a series of springcontacts each connected with the other branch of said talking-circuits, one to each branch, and interposed between said talking-circuit contacts and said generator-circuit contact, said spring-contacts normally in contact with one set of the opposed stationary contacts, a series of insulating-pins provided at one end with projecting conductors electrically counected together in pairs and adapted when inserted between said spring-contacts and their opposed stationary contacts to disconnect the spring-contacts from the opposed stationary contacts and connect them with the conducting part of the pins whereby any two subscribers can be connected together, said pins and spring-contacts so constructed that when either of said pins is given a further movement, the signal of the associated subscriber is operated, said pin returning,` to its normal position when released.
VILLIAM O. MEISSNER.
DONALD M. CARTER, FRANCIS M. IRELAND.