US778877A - Telephony. - Google Patents

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US778877A
US778877A US20595304A US1904205953A US778877A US 778877 A US778877 A US 778877A US 20595304 A US20595304 A US 20595304A US 1904205953 A US1904205953 A US 1904205953A US 778877 A US778877 A US 778877A
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switch
telephone
actuating
circuit
appliance
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Albert Meinema
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    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04QSELECTING
    • H04Q3/00Selecting arrangements

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  • My invention relates to party telephonelines, and has for its object the provision of improved apparatus at substations whereby selection may be effected from the exchange.
  • H y invention has for its principal object the provision of such mechanism whereby the operators mayat all times efiect the actuation of the selecting mechanism whether the telephone-receivers are on or off the switch-hooks.
  • My invention finds a very practicable embodiment in apparatus of the general nature set forth in my Patent No.757,826,dated April 19, 1904, wherein I have provided a rotatable switch-controlling wheel at each station, carrying a lug or other switch-actuating element that may be placed in such mechanical relation with switch parts at a calling-station through the agency of electromagnetic means provided at such station and operated by switching mechanism at the exchange to close the signaling-circuit containing the calling-bell and to permit the closure of the telephonic circuit at the called station, this latter result being preferably accomplished both with regard to the receiver and the transmitter when the telephone-receiver is removed from its switchhook.
  • My invention in connection with this apparatus is realized by providing a latching mechanism that temporarily secures the switch parts in the relative positions in which they have been placed by the electromagnetic mechanism and providing an escaping engagement between the switch-hook and the circuitchanging mechanism operated thereby, whereby said switch-hook does not form a mechanical obstruction to the restoring movement of the switch elements, which movement may be accomplished by releasing the latch through the agency of the electromagnetic mechanism controlled by the operator.
  • Figure l is a diagrammatic view of a party telephoneline,(one station only being shown,)
  • FIG. 2 is a detail view of the latching mechanism and associated parts, on an enlarged scale, the latch in this figure being in locking engagement with a switch element.
  • Fig. 3 is a view of the latching mechanism in the direction of arrow 3, Fig. 2.
  • Fig. A is a view of the portion of the telephone switch-hook in the direction of arrow 4,Fig. 2.
  • Fig. 1 enough of a telephone-exchange system to render an understanding of my invention clear.
  • ure I have disclosed a party telephone-line extending by its limbs a and b to an exchange, where they terminate in the line-springs of a spring-jack 0, one of which when unengaged by a plug is in circuit with the annunciator (Z.
  • an ordinary connecting-plug 0, whose sleeve is normally in open circuit with a grounded calling-generator e and whose tip and sleeve may be connected with a battery 6 by a polechanging switch 6 which connects one pole of the battery with the tip and the other with the sleeve in one position and reverses the connection of the battery in the other position, the battery thus serving to direct current over the limbs in opposite directions.
  • a Z there is located an electromagnetic apparatus having two magnet-helices ff, which may be organized in a unitary structure.
  • the magnetic device f f includes a permanent magnet f that serves or tends to magnetize the soft-iron cores of the helices ff to cause the same to present similar poles to the oscillating softiron armature f
  • the helices f f are differentially wound and may have such direction with respect to the polarities of the soft-iron cores and the battery that when the key 6 is moved in one direction the actuating element g will be In said fig-- moved toward the right, causing the arm g by its engagement with one of the pins 9 to effect a clockwise rotation of the wheel g and an advance of the insulating-block 9'', carried by the wheel one step, this wheel being advanced against the force of the helical spring
  • the current through the helices f f is reversed, causing the actuating element g to be moved in a reverse direction, whereby the pin g, carried upon the arm will engage the detent g and remove its nose from
  • a subscriber removes his receiver, and thereby effects connection of the parts a and Z, the said subscriber by operating his generator m effecting a closure of the contacts m, whereupon the said generator m is connected with the telephone-limb a, enabling the subscriber to operate the annunciator cZ.
  • This same bodily movement of the wheel g effects the connection of the telephone-receiver a in the circuit of a calling-station, the local transmitter-circuit being closed at p, as is well understood to those skilled in the art.
  • Fig. 1 the receiver a is supposed to be on the switch-hook, as indicated in dotted lines.
  • Fig. 2 the said receiver is removed.
  • the operator in selecting a station operates the suitable key 6 the number of times necessary to place the block g into line with the free ends of the springs 'Z 71 and the button Z.
  • the operator does not accomplish any bodily movement of the wheel g and I therefore make the finger g longer than the finger it, so that said. finger g may effect engagement of the parts Z it it being unnecessary for the operator to effect connection of the partsz' and Z, as this may be done by the called subscriber when he removes the telephone from its switch-hook.
  • the'key e is moved to include the operators signalgenerator 6 in circuit with the limb a, that is now in electrical connection with said parts a 7': and the receiving-bell r.
  • the restoration of the selecting apparatus was to be accomplished only when the subscribers had indicated that they were through with the conversation.
  • the operator is not thus restricted in her control of the selecting apparatus, for when the lower end of the rod g is moved toward the left the nose w on the arm g comes into engagement with the upper end of the latch or trigger a to release the spring a, thereby opening the telephone circuit, said trigger having previously automatically engaged the spring when said spring was thrust into engagement with the pin Z.
  • the detent g and the arm are pivoted upon the framework 00, which also constitutes the mounting for the wheel.
  • the arm g is preferably not directly pivoted to this frame, but is desirably pivoted upon a swinging link .0. that is pivoted to the frame.
  • the actuating element g effects movement of the arm by passing between two pins 2 thereon, as shown, the arm in turn actuating the detent g through the agency of the pin g, as hitherto specified.
  • the preferred manner of efl ecting escaping engagement between the frame a" and the switch-hook 2 is by providing arecess in the base of the frame and a tripping-dog 2' at the pivoted end of the switch-hook normally in engagement with the said recess and escaping from such engagement when the switch-hook has been fully elevated upon the removal of the receiver therefrom, whereupon the said frame 0? may be restored to its normal position, which is preferably immediately accomplished by some agency, as a coil-spring 2 inclosing the guide-rod m and moving the frame 0 and the parts carried thereby in an opposite direction to that in which said frame is moved by the switch-hook.
  • a coil-spring 2 inclosing the guide-rod m and moving the frame 0 and the parts carried thereby in an opposite direction to that in which said frame is moved by the switch-hook.
  • a bodilymovable actuating appliance for actuating the switch device
  • electromagnetic mechanism at the substation for operating said switch-actuating appliance to close the circuit through the signal-receiver at said station, switching apparatus at the exchange for operating said electromagnetic mechanism, a telephone-receiver switch-hook having escaping engagement with the switch-actuating appliance and serving to engage said switch-actuating appliance to move the same and thereby effect closure of the telephone-circuit and then escape the switch-actuating appliance, and a latch thrust into latching connection with an actuated element of said switch when thus operated by the switch-actuating appliance to maintain the circuit closed thereby, said latch beingadapted to be released by the operator through the agency of said electromagnetic mechanism, substantially as described.
  • a selective signaling telephone system the combination with a telephone-line extending to an exchange, of a switch device at a substation of the telephone-line controlling the telephone and' signal circuits, a bodilymovable actuating appliance for actuating the switch device, electromagnetic mechanism at the substation for operating said switch-actu" ating appliance, said switch-actuating appliance including a rotating member carrying two pins g 72, of unequal effective length, the switch device including circuit-controlling springs or elements; k included in the signalreceiver circuit at said substation and adapted to be closed by one of said pins, and a telephone contact element Z, the other of said pins serving to connect the three contact elements 2' 7a and Z and then escape the switch-actuating appliance, and a latch thrust into latching connection with an actuated element of said switch when thus operated by the switchac tuating appliance to maintain the circuit closed thereby, said latch being adapted to be released by the operator through the agency of said electromagnetic mechanism, substantially as described.
  • a selective signaling telephone system the combination with a telephone line extending to an exchange, of a switch device at a substation of the telephone-line controlling the telephone and signal circuits, a bodilymovable actuating appliance for actuating the switch device, electromagnetic mechanism at the substation for operating said switch-actuating appliance, said switch-actuating appliance including a rotating member carrying two pins g h of unequal length, the switch device including circuit-controlling elements a Zcontrolling the telephone-receiver and signal-receiver circuits and adapted to be controlled by such switch-actuating appliance, partially by the switching mechanism at the exchange to effect closure of the signal-receiving circuit, the switch-hook serving to effect bodily movement of the sald switch-actuating appliance'to effect closure of the telephone-receiver circuit and then escape the switch-actuating appliance, and a latch thrust into latching connection with the actuated element 2' of said switch when thus operated by agency of said electromagnetic mechanism,

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  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Telephone Set Structure (AREA)

Description

PATENTED JAN. 3, 1905.
main/tor."-
JlZrt Jlzfrwnm A. MEINBMA. TELEPHONY.
APPLICATION FILED MAY 2, 1904.
Patented January 3, 190 5.
PATENT OEEIcE.
ALBERT MEINEMA, OF CHICAGO, ILLINOIS.
TELEPHONY.
SPECIFICATION forming part of Letters Patent No. 778,877, dated January 3, 1905.
Application filed May 2, 1904. Serial N0. 205|953.
To (LZZ whom it may concern.-
Be it known that I, ALBERT MEINEMA, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented a certain new and useful Improvement in Telephony, of which the following is a full, clear, concise, and exact description, reference being had to the accompanying drawings, forming a part of this specification.
My invention relates to party telephonelines, and has for its object the provision of improved apparatus at substations whereby selection may be effected from the exchange.
H y invention has for its principal object the provision of such mechanism whereby the operators mayat all times efiect the actuation of the selecting mechanism whether the telephone-receivers are on or off the switch-hooks.
My invention finds a very practicable embodiment in apparatus of the general nature set forth in my Patent No.757,826,dated April 19, 1904, wherein I have provided a rotatable switch-controlling wheel at each station, carrying a lug or other switch-actuating element that may be placed in such mechanical relation with switch parts at a calling-station through the agency of electromagnetic means provided at such station and operated by switching mechanism at the exchange to close the signaling-circuit containing the calling-bell and to permit the closure of the telephonic circuit at the called station, this latter result being preferably accomplished both with regard to the receiver and the transmitter when the telephone-receiver is removed from its switchhook. My invention in connection with this apparatus is realized by providing a latching mechanism that temporarily secures the switch parts in the relative positions in which they have been placed by the electromagnetic mechanism and providing an escaping engagement between the switch-hook and the circuitchanging mechanism operated thereby, whereby said switch-hook does not form a mechanical obstruction to the restoring movement of the switch elements, which movement may be accomplished by releasing the latch through the agency of the electromagnetic mechanism controlled by the operator. I will explain my invention more fully by reference to the accompanying drawings, in which Figure l is a diagrammatic view of a party telephoneline,(one station only being shown,)
showing the apparatus of my invention in association therewith. Fig. 2 is a detail view of the latching mechanism and associated parts, on an enlarged scale, the latch in this figure being in locking engagement with a switch element. Fig. 3 is a view of the latching mechanism in the direction of arrow 3, Fig. 2. Fig. A is a view of the portion of the telephone switch-hook in the direction of arrow 4,Fig. 2.
Like parts are indicated by similar characters of reference throughout the different figures.
I have indicated in Fig. 1 enough of a telephone-exchange system to render an understanding of my invention clear. ure I have disclosed a party telephone-line extending by its limbs a and b to an exchange, where they terminate in the line-springs of a spring-jack 0, one of which when unengaged by a plug is in circuit with the annunciator (Z. At the exchange there is illustrated an ordinary connecting-plug 0, whose sleeve is normally in open circuit with a grounded calling-generator e and whose tip and sleeve may be connected with a battery 6 by a polechanging switch 6 which connects one pole of the battery with the tip and the other with the sleeve in one position and reverses the connection of the battery in the other position, the battery thus serving to direct current over the limbs in opposite directions. At each of the substations of the party-line a Z) there is located an electromagnetic apparatus having two magnet-helices ff, which may be organized in a unitary structure. In the construction illustrated the magnetic device f f includes a permanent magnet f that serves or tends to magnetize the soft-iron cores of the helices ff to cause the same to present similar poles to the oscillating softiron armature f The helices f f are differentially wound and may have such direction with respect to the polarities of the soft-iron cores and the battery that when the key 6 is moved in one direction the actuating element g will be In said fig-- moved toward the right, causing the arm g by its engagement with one of the pins 9 to effect a clockwise rotation of the wheel g and an advance of the insulating-block 9'', carried by the wheel one step, this wheel being advanced against the force of the helical spring When the key 0 is moved in the opposite direction, the current through the helices f f is reversed, causing the actuating element g to be moved in a reverse direction, whereby the pin g, carried upon the arm will engage the detent g and remove its nose from the path of the pins 9, permitting the spring g to restore the wheel g to its initial position, this position being defined by means of a finger g engaging a stationary block 9 It will be understood that the blocks upon the different wheels g at the different stations occupy differing distances from the finger so that no two fingers occupy the same relative operative positions. It is obvious that while a number of movements of the key 6 is necessary to set wheels but one operation of the key is necessary to release the .wheels and permit all of them to be restored v to their normal positions. In the normal position of each wheel the enlargement hof the wheel'is placed opposite the contact-springs Zr: and the button Z. In this position a bodily transverse movement of the wheel, which is permitted because the mounting of the wheel is capable of reciprocating upon the slide m, will effect, first, a closure of the springs Z and 7s and thereafter the engagement of the spring 2' with the button Z. At a calling-station a subscriber removes his receiver, and thereby effects connection of the parts a and Z, the said subscriber by operating his generator m effecting a closure of the contacts m, whereupon the said generator m is connected with the telephone-limb a, enabling the subscriber to operate the annunciator cZ. This same bodily movement of the wheel g effects the connection of the telephone-receiver a in the circuit of a calling-station, the local transmitter-circuit being closed at p, as is well understood to those skilled in the art.
In Fig. 1 the receiver a is supposed to be on the switch-hook, as indicated in dotted lines. In Fig. 2 the said receiver is removed. The operator in selecting a station operates the suitable key 6 the number of times necessary to place the block g into line with the free ends of the springs 'Z 71 and the button Z. The operator does not accomplish any bodily movement of the wheel g and I therefore make the finger g longer than the finger it, so that said. finger g may effect engagement of the parts Z it it being unnecessary for the operator to effect connection of the partsz' and Z, as this may be done by the called subscriber when he removes the telephone from its switch-hook. When the parts a and 76 have been connected by the operator, the'key e is moved to include the operators signalgenerator 6 in circuit with the limb a, that is now in electrical connection with said parts a 7': and the receiving-bell r.
In the device of my aforesaid patent the restoration of the selecting apparatus was to be accomplished only when the subscribers had indicated that they were through with the conversation. By means of my present invention the operator is not thus restricted in her control of the selecting apparatus, for when the lower end of the rod g is moved toward the left the nose w on the arm g comes into engagement with the upper end of the latch or trigger a to release the spring a, thereby opening the telephone circuit, said trigger having previously automatically engaged the spring when said spring was thrust into engagement with the pin Z. The detent g and the arm are pivoted upon the framework 00, which also constitutes the mounting for the wheel. The arm g is preferably not directly pivoted to this frame, but is desirably pivoted upon a swinging link .0. that is pivoted to the frame. The actuating element g effects movement of the arm by passing between two pins 2 thereon, as shown, the arm in turn actuating the detent g through the agency of the pin g, as hitherto specified.
The preferred manner of efl ecting escaping engagement between the frame a" and the switch-hook 2 is by providing arecess in the base of the frame and a tripping-dog 2' at the pivoted end of the switch-hook normally in engagement with the said recess and escaping from such engagement when the switch-hook has been fully elevated upon the removal of the receiver therefrom, whereupon the said frame 0? may be restored to its normal position, which is preferably immediately accomplished by some agency, as a coil-spring 2 inclosing the guide-rod m and moving the frame 0 and the parts carried thereby in an opposite direction to that in which said frame is moved by the switch-hook. obviously, may be employed for effecting separable actuating connection between the switch-hook 2 and the actuated element .00 of the switching device without departing from the spirit of my invention.
It will be observed that the grounded signal-bell branches are automatically disconnected from the line by the switch-hooks when relieved of the receivers.
It is obvious that the invention I have applied to the invention of my aforesaid patent need not be'restricted to this application, and I do not, therefore, wish to be limited to the precise construction illustrated; but,
Having thus described my invention, I claim as new and desire to secure by Letters Patent 1. In a selective signaling telephone system, Q
the combination with a telephone-line extending to an exchange, of a switch device Other means,
at a substation of thetelephone-line controllingthe telephone and signal circuits, a bodilymovable actuating appliance for actuating the switch device, electromagnetic mechanism at the substation for operating said switch-actuating appliance to close the circuit through the signal-receiver at said station, switching apparatus at the exchange for operating said electromagnetic mechanism, a telephone-receiver switch-hook having escaping engagement with the switch-actuating appliance and serving to engage said switch-actuating appliance to move the same and thereby effect closure of the telephone-circuit and then escape the switch-actuating appliance, and a latch thrust into latching connection with an actuated element of said switch when thus operated by the switch-actuating appliance to maintain the circuit closed thereby, said latch beingadapted to be released by the operator through the agency of said electromagnetic mechanism, substantially as described.
2. In a selective signaling telephone system, the combination with a telephone-line extending to an exchange, of a switch device at a substation of the telephone-line controlling the telephone and' signal circuits, a bodilymovable actuating appliance for actuating the switch device, electromagnetic mechanism at the substation for operating said switch-actu" ating appliance, said switch-actuating appliance including a rotating member carrying two pins g 72, of unequal effective length, the switch device including circuit-controlling springs or elements; k included in the signalreceiver circuit at said substation and adapted to be closed by one of said pins, and a telephone contact element Z, the other of said pins serving to connect the three contact elements 2' 7a and Z and then escape the switch-actuating appliance, and a latch thrust into latching connection with an actuated element of said switch when thus operated by the switchac tuating appliance to maintain the circuit closed thereby, said latch being adapted to be released by the operator through the agency of said electromagnetic mechanism, substantially as described.
3. In a selective signaling telephone system, the combination with a telephone line extending to an exchange, of a switch device at a substation of the telephone-line controlling the telephone and signal circuits, a bodilymovable actuating appliance for actuating the switch device, electromagnetic mechanism at the substation for operating said switch-actuating appliance, said switch-actuating appliance including a rotating member carrying two pins g h of unequal length, the switch device including circuit-controlling elements a Zcontrolling the telephone-receiver and signal-receiver circuits and adapted to be controlled by such switch-actuating appliance, partially by the switching mechanism at the exchange to effect closure of the signal-receiving circuit, the switch-hook serving to effect bodily movement of the sald switch-actuating appliance'to effect closure of the telephone-receiver circuit and then escape the switch-actuating appliance, and a latch thrust into latching connection with the actuated element 2' of said switch when thus operated by agency of said electromagnetic mechanism,
substantially as described.
4. In aselectivesignalingtelephonesystem, the combination with a telephone-line extending to an exchange, of a switch device at a substation, a bodily-movable actuating appliance for actuating the switch device, electromagnetic mechanism at said station for operating said switch-actuating appliance, switching mechanism at the exchange for operating said electromagnetic mechanism, said switch device including contact elements controlling the telephone-receiver and sign al-receiver circuits at said substation, two of said elements being adapted for engagement through the agency of said switch-actuating appliance when operated from the exchange to eifect closure of the signal-receiving circuit, a switch-hook adapted to etfect bodily movement of the switch-actuating appliance to cause the remaining contact element to close the telephone-receiver circuit and then escape the switch-actuating appliance, and a latch thrust into latching connection with the actuated element of said switch when thus operated by the switch-actuating appliance to maintain the circuit closed thereby, said latch being adapted to be released by the operator through the agency of said electromagnetic mechanism, substantially as described.
5. In asubstation outfit for party telephonelines, the combination with switching mechanism governing the subscribers circuit, of a switch-hook for actuating the switching mechanism, a latch operated by the switch-hook and brought into latching engagement with an actuated element of the switching mechanism to hold the same independently of the switch-hook. and electromagnetic mechanism for setting the switching mechanism and releasing the latch, substantially as described.
6. The combination withatelephone-line extending from a plurality of stations to an ex change, of switching mechanism at each station governing the subscribers circuit, of a switch-hook for actuating the switching mechanism, having escaping engagement with said switching mechanism when it is operated by the switch-hook to close the subscribers circuit, a latch brought into latching engagement with an actuated element of the switching mechanism to hold the same independently of the switch-l1ook,and electromagnetic mechanism for setting the switching mechanism and releasing the latch, whereby control of the substations'may be had from the exchange independently of the subscribers,substantially as described.
7. In a selective signaling telephone system,
the combination with a telephone-line extending to an exchange, of a switch device at a substation of the telephone-line controlling the telephone and signal circuits, a bodily-movable actuating appliance for actuating the switch device, electromagnetic mechanism at the substation for operating said switch-actuating appliance, switching mechanism at the exchange for operating said electromagnetic mechanism whereby said switch-actuating appliance may be set in position to close the telephone-circuit controlled thereby, a telephoneswitch hook also controlling the said telephone-circuit having escaping engagement with the switch-actuating appliance and serving when released to bodily move said switchactuating appliance and to complete the 010- sure of the telephone-circuit and then escape the switch-actuating appliance, and a latch thrust into latching connection with an actuated element of said switch when thus operated by the switch-actuating appliance to maintain the circuit closed thereby, said latch being adapted to be released by the operator through the agency of said electromagnetic mechanism, substantially as described.
8. In aselective signaling telephone system, the combination with a telephone-line extending to an exchange, of a switch device at a substation of the telephone-line controlling the telephone and signal circuits, a bodily-movable actuating appliance for actuating the switch device, electromagnetic mechanism at the substation for operating said switch-actuating appliance, switching mechanism at the exchange for operating said electromagnetic mechanism whereby said switch-actuating appliance may be set in position to close the telephone circuit controlled thereby, a telephone-switch hook also controlling the telephone-circuit having escaping engagement with the switch-actuating appliance and serving when released to bodily move said switchactuating appliance and to complete the closure of the telephone circuit', a signal-receiver at said substation, a switch controlling the circuit of the signal-receiver closed by the aforesaid switch-actuating appliance when actuated by the operator, and a latch thrust into latching connection with an actuated element of said switch when thus operated by the switch-actuating appliance to maintain the circuit closed thereby, said latch being adapted to be released by the operator through the agency of said electromagnetic mechanism, substantially as described.
In witness whereof I hereunto subscribe my 7 name this 30th day of April, A. D. 1904:.
ALBERT MEINEMA.
Witnesses:
G. L. ORAGG, O. H. CRAWFORD.
US20595304A 1904-05-02 1904-05-02 Telephony. Expired - Lifetime US778877A (en)

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