US1678301A - Selecting device for telephone systems - Google Patents

Selecting device for telephone systems Download PDF

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US1678301A
US1678301A US163007A US16300727A US1678301A US 1678301 A US1678301 A US 1678301A US 163007 A US163007 A US 163007A US 16300727 A US16300727 A US 16300727A US 1678301 A US1678301 A US 1678301A
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pawl
armature
pawls
magnet
movement
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US163007A
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Quassowski Paul
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Siemens and Halske AG
Siemens AG
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Siemens AG
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    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01HELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H67/00Electrically-operated selector switches
    • H01H67/02Multi-position wiper switches
    • H01H67/14Multi-position wiper switches having wipers movable in two mutually perpendicular directions for purpose of selection
    • H01H67/16Multi-position wiper switches having wipers movable in two mutually perpendicular directions for purpose of selection one motion being rotary and the other being parallel to the axis of rotation, e.g. Strowger or "up and around" switches

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  • PAUL QU'ASSOWSKI or BERLIN, GERMANY, ⁇ ASSIGNOR 'IO SIEMENS & HALSKE AKTIEN- GESELLSCHAFT, wnnunnwnax, or srnlannsscranr, unaa BERLIN, enniyienY.
  • the invention relates to selecting devices for telephone systems, in which movable contacts are brought into engagement with stationary terminals by means of two positioning movements in different directions.
  • the movable contacts make either two rotary movements or one vertical and one rotary movement.
  • a particularly simple arrangement for enabling operating pawls actuated by one magnet, to work in a reliable manner, is obtained according to the invention, by attaching the operating pawls for two directions of motion to a common lever, which is electro-magnetically controlled.
  • the arrangement permits the two pawls to operate in a satisfactory manner; it can therefore be used with advantage for all selecting devices having one driving magnet.
  • this intermediate member is directly controlled by the armature of the driving magnet and consists of an angular lever with two arms, eacharm carrying one operating pawl.
  • the arrangement is so contrived that when the armature falls'back the operating pawl for one of the positioning movements functions and when the armature is attracted the operating pawl for the other movement is actuated. This enables the operating pawl for the first direction of movement to assume its functioning position already at the commencement of the second direction of movement.
  • FIG. 1-7 show by way of example twomethods of carrying out the invention, applied to a double rotary selecting device and to a vertical rotary switch, the latter also known as Strowger switch.
  • Fig. 1 shows a front view of a double rotary switch
  • Fig. 2 is a side view thereof,-
  • Fig. 3 is a view looking downwards.
  • Fig. 4 shows, in three elevations, a common guide piece for both operating pawls, the
  • FIG. 5 shows a front view of a ver tical and rotary switch
  • Fig. 6 shows a side view
  • Fig. 7 shows a view looking clownward. Only those parts are shown inFigs. 5 to 7 which are required for understanding the invention.
  • armature 5 of this magnet is rotatably mounted on a fulcrum .7 of the yoke 3 and is held there by means of aleaf spring 6 to which the extremity of armature 5 is fastened by means of screw 8.
  • aleaf spring 6 One end of this spring enters a slot in member 9 in the yoke 3 and the other end enters an opening in the leaf spring 10.
  • the spring 6 is put under tension, and serves to return the armature 5 from its operated position to its normal position.
  • An angular lever 11 having two arms is attached to the armature 5, and the operating pawls 12 and 13 are rotatably mounted at the end of these arms. Both the operating pawls 12 and 13 engage a common guide member 14, shown in detail in Fig. 4., which is mounted on the pate 1.
  • this guide member 141' forces the operating pawls 12 and 13 to adhere to a particular direction of movement.
  • the pawl 12 effects the rotary movement in the vertical direction
  • the pawl 13 effects the rotary movement in the horizontal direction.
  • the part 15, which is required for the first mentioned direction of movement, is provided with teeth 16. It carries the contact arms 17 and is rotatably mounted on the bolt 18, which is rigidly fixed'to the ring 19.
  • This ring 19 is provided with slots20, through which the part 15 is taken. Rigidly attached to this ring 19 is also the segment 21 having teeth 22 for the horizontal rotary move ment.
  • the ring 19 with the operating seg ments 15 and 21 is mounted on the shaft 23. The latter is held by two parallel parts of the plate 1.
  • the springs 24 and 25 maintain the part 15 and the segment 21 in their normal position.
  • the part 15, which is ill) required for the first direction of movement and carries the contact arms 17, is also provided with a stop 28, which ends in the point of rotation 29 of the second rotary movement when the selecting device is in its normal position.
  • Lever 30 extends past this point of rotation, which is made in one piece with the detent 31 provided for the horizontal rotary movement.
  • the lever 30 and the detent 31 are rotatably mounted on the shaft 32.
  • Thedetent is so arranged that it controls the operating pawl by means of a member 33.
  • the detent-31 and thus also the operating pawl 13 are litted oif the teeth 22 of the segn'ient 21, is best seen in Fig. 3.
  • the detent 33 and pawl 13 are moved towards the teeth 22 by means of spring 34 which 15 clamped around point 32.
  • an auxiliary electro-magnet 35 is pro vided, the armature 36 of" which has an engaging member 37, which controls the detent 31 and the operating pawl 13.
  • the electromagnet 35 can also be utilized for taking care of the functions of a relay usually employed in the circuit of the switch for changing over from the vertical. to the rotary movement.
  • circuits are well known in the art, and in view of the fact that the present invention chiefly concerned with the structure of the switch, and with its functions, regardless of other possibilities which may suggest themselves, a detailed discussion of the circuit is omitted.
  • the auxiliary magnet 35 is first energized. Its armature 36 is thereby attracted, moving the member 37 toward the detent 31 and supporting the same, and with it the operating pawl 13 in the position, in which it is normally held by the stop 28. It will be observed that the stop 28 is integral with the member 15 provided for the movement in the first direction. Therefore, when the first movement is executed, stop 28 is removed from the position shown in the drawings, relay 35 takes its place during the movement in the first direction, maintaining the pawl 13 and detent 31 out of engagement with the segment 21 as described above.
  • pawl 15 is upon the restoration of armature 5 to its. normal position. It will be seen that member 11 is rotated about fulcrum 7 (Fig. 2) upon the attraction of armature 5 thus lifting pawl 12 into engagement with the next tooth of ratchet 16. Now when armature 5 is retracted, member 11 will have its direction of rotation reversed and as pawl 12 is forced downward, the ratchet 16 will be rotated in a clockwise direction (Fig. 1).
  • Pawl 13 is arranged to operate in the reverse order, that is, move ratchet 22 upon the attraction of armature 5. A further displacement of the wipers 17 in the second direction is then effected by the same motor magnet 2 (after the electro-magnet'35 has been deenergized) by means of the pawl 13, the pawl 12 being then rendered inoperative by the movement of the segment 15 which takes the ratchet 16 out of reach of the pawl 12. This is achieved because pawl 13 for the second direction of movement actuates its ratchet when armature 5 is attracted, while the pawl 12 can only move the part 15 when armature 5 commences to fall back.
  • the driving magnet 2 receives a further. train of impulses of current, thereby advancing part 15 in a vertical direction.
  • This causes the detent 26 to reach a stop 38 attached to the plate 1.
  • the stop 38 lifts the pawl 26 out of the ratchet 16 and releases the displaced part 15.
  • the latter now returns to its normal position with the assistance of springs 24.
  • the stop 23 also returns the lever 30 to the point of rotation 29. In this position the lever 30 holds the de tent 31 and the pawl 13 out of engagement with the ratchet 22; hence thespring 25 rotates the segment 21 back to its normal position, thus resetting the selecting device to normal.
  • the vertical rotary switch shown in Figs. 5, 6 and 7, functions in substantially the same manner as above described for the selecting device with double rotary motion. A brief discussion will therefore suflice. Similarly to the switching device described in the foregoing, this switch is also equipped with an auxiliary magnet serving the same purpose as the magnet of Figs. 1to 4.. This magnet is not shown in the Figs. 5 to 7, inclusive, but its function will be readily understood from the following description.
  • auxiliary magnet acts on a detent (such as 31 in Figs. 1 to 3) and the detent in turn acts on a pawl (such as 13, by means of a member such as 37 in Figs. 1 to 3), maintaining pawl and detent in inoperated position as described.
  • the armature 5, which is mounted at 7 operates the two-armed angular lever 11.
  • the pawl 12 only can operate the ratchet 16 for the vertical movement; hence, the wipers 17 are lifted to the level corresponding to the number of current impulses.
  • the release of the selecting device is effected in the same manner as described in case of the double rotary switch, by making the actuation of the detent 31 dependent on the position of the movable part 15, and that of the detent 26 dependent on the position of the part 15 with respect to a fixed stop, which lifts this pawl out of engagement with its ratchet 16.
  • the part 15 is returned to its normal position by means of the tension of the spring 24.
  • the part 15 is rotated back by means of the spring 25.
  • the part 15, which is provided with the teeth 16. is loosely guided in a groove in the shaft 38, while the part 21 having the teeth 22, is rigidly fixed to the shaft 38.
  • the shaft is so mounted in the parts 39 and 40 that it has only rotary movement. It will be readily seen, however, that the switch can easily be so constructed that the shaft 38 is carried along during the vertical and during the rotary setting.
  • An automatic switch comprising stationary terminals, wipers successively movable in two different planes to engage said terminals, two separate pawls for executing said movements, an electromagnet having an armature for controlling said pawls, one of said pawls being effective upon attraction of said armature and the other pawl being effective upon retraction of said armature.
  • An automatic switch comprising stationary terminals and movable wipers, two
  • stationary terminals wipers having a plu rality of'positioning movements executed in succession in a definite sequence to advance said wipers into engagement with said terminals, a plurality of operating pawls, each of said movements being executed by a certain one of said pawls, a common member for controlling said pawls, an electromagnet having an armature, said common member being attached to said armature, one of said pawls being effective upon the attraction of said armature and the other pawl being effective upon the retraction of said armature.
  • a plurality of stationary contacts wipers having a plurality of rotary positioning movements executed in succession in a definite sequence to advance said wipers into engagement with certain of said terminals, each movement being in a difierent plane, a plurality of pawls for executing the plurality of rotary movements, and common electromagnetically controlled means for operating said pawls to execute first one rotary movement then another rotary movement.
  • An automatic switch comprising stationary terminals, wipers successively rotatable in two different planes to engage said terminals, two separate pawls and two separate semi-circular ratchets for executing the two rotary movements, an angular lever having two arms each arm carrying one of said pawls, and an electro-magnet for directly controlling said lever.

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Description

July 24, 1928. m 1,678,301
P. QUASSOWSKI SELECTING DEVICE FOR TELEPHONE SYSTEMS Filed Jan. 24, 1927 :s Sheets-Sheet 1 InuenIun- Paul [fluassumski "Jul 24, 1928. 1,678,301
P. QUASSOWSKI SELECTING DEVICE FOR TELEPHONE SYSTEMS Filed Jan. 24, 1927 s Sheets-Sheet 2 TLUETLTUT' Faul Eiuassumskl July 24, 1928. 1,678,301
P. QUASSOWSKI SELECTING DEVICE FOR TELEPHONE SYSTEMS Filed Jan. 24, 1927 5 Sheets-Sheet a F 5 F 151 E a I j /7 F f 2/ 7 /2 "/26 Ll /7 T 7 f w L F 7 W 2 1f lnueniur' Paul Quassumslcz' Patented July 24, 1928.
UNITED STATES PATENT- OFFICE.
PAUL QU'ASSOWSKI, or BERLIN, GERMANY, {ASSIGNOR 'IO SIEMENS & HALSKE AKTIEN- GESELLSCHAFT, wnnunnwnax, or srnlannsscranr, unaa BERLIN, enniyienY.
SELECTING DEVICE FOR TELEPHONE SYSTEMS.
Application filed January 24, 1927, Serial No. 163,007, and in Germany December 6, 1926.
The invention relates to selecting devices for telephone systems, in which movable contacts are brought into engagement with stationary terminals by means of two positioning movements in different directions. For this purpose the movable contacts make either two rotary movements or one vertical and one rotary movement.
In the usual selecting devices of this type the operating pawls required for executing these movements are mostly under control of separate motor magnets. \Vhenever a single motor magnet is used for cont-rolling both pawls, complicated switching devices are required,'in order to cause either one or the other of the two operating pawls to be brought into action.
A particularly simple arrangement for enabling operating pawls actuated by one magnet, to work in a reliable manner, is obtained according to the invention, by attaching the operating pawls for two directions of motion to a common lever, which is electro-magnetically controlled. When using only one common intermediate member, the arrangement permits the two pawls to operate in a satisfactory manner; it can therefore be used with advantage for all selecting devices having one driving magnet.
According to the invention this intermediate member is directly controlled by the armature of the driving magnet and consists of an angular lever with two arms, eacharm carrying one operating pawl.
The arrangement is so contrived that when the armature falls'back the operating pawl for one of the positioning movements functions and when the armature is attracted the operating pawl for the other movement is actuated. This enables the operating pawl for the first direction of movement to assume its functioning position already at the commencement of the second direction of movement. a i
' The drawings, comprising Figs. 1-7, show by way of example twomethods of carrying out the invention, applied to a double rotary selecting device and to a vertical rotary switch, the latter also known as Strowger switch.
Fig. 1 shows a front view of a double rotary switch; Fig. 2 is a side view thereof,-
and Fig. 3 is a view looking downwards. Fig. 4:, shows, in three elevations, a common guide piece for both operating pawls, the
latter being indicated by means of dotted lines. Fig. 5 shows a front view of a ver tical and rotary switch; Fig. 6 shows a side view, and Fig. 7 shows a view looking clownward. Only those parts are shown inFigs. 5 to 7 which are required for understanding the invention.
Referring now particularly to Figs. 1, 2, and 3, it will be seen that all parts are attached to a suitably shaped plate 1. The driving magnet 2 is fixed to an angle iron 3, which is connected to the plate 1 by means of screws 4. The armature 5 of this magnet is rotatably mounted on a fulcrum .7 of the yoke 3 and is held there by means of aleaf spring 6 to which the extremity of armature 5 is fastened by means of screw 8. One end of this spring enters a slot in member 9 in the yoke 3 and the other end enters an opening in the leaf spring 10. Thus the spring 6 is put under tension, and serves to return the armature 5 from its operated position to its normal position. An angular lever 11 having two arms is attached to the armature 5, and the operating pawls 12 and 13 are rotatably mounted at the end of these arms. Both the operating pawls 12 and 13 engage a common guide member 14, shown in detail in Fig. 4., which is mounted on the pate 1. When the magnet 2 is energized, this guide member 141' forces the operating pawls 12 and 13 to adhere to a particular direction of movement. The pawl 12 effects the rotary movement in the vertical direction, while the pawl 13 effects the rotary movement in the horizontal direction. The part 15, which is required for the first mentioned direction of movement, is provided with teeth 16. It carries the contact arms 17 and is rotatably mounted on the bolt 18, which is rigidly fixed'to the ring 19. This ring 19 is provided with slots20, through which the part 15 is taken. Rigidly attached to this ring 19 is also the segment 21 having teeth 22 for the horizontal rotary move ment. The ring 19 with the operating seg ments 15 and 21 is mounted on the shaft 23. The latter is held by two parallel parts of the plate 1. The springs 24 and 25 maintain the part 15 and the segment 21 in their normal position. When pawl 12 is actuated the part 15 is locked by means of the detent 26, which is connected to the ring 19 by means of the projection 27 and is carried on when rotation is effected. The part 15, which is ill) required for the first direction of movement and carries the contact arms 17, is also provided with a stop 28, which ends in the point of rotation 29 of the second rotary movement when the selecting device is in its normal position. Lever 30 extends past this point of rotation, which is made in one piece with the detent 31 provided for the horizontal rotary movement. The lever 30 and the detent 31 are rotatably mounted on the shaft 32. Thedetent is so arranged that it controls the operating pawl by means of a member 33.
hen the selecting device is in its normal position, the detent-31 and thus also the operating pawl 13 are litted oif the teeth 22 of the segn'ient 21, is best seen in Fig. 3. However, when the device leaves its normal position, the detent 33 and pawl 13 are moved towards the teeth 22 by means of spring 34 which 15 clamped around point 32.
-Now, in order to prevent the pawl 13 engaging during the first positioning movement, an auxiliary electro-magnet 35 is pro vided, the armature 36 of" which has an engaging member 37, which controls the detent 31 and the operating pawl 13. The electromagnet 35 can also be utilized for taking care of the functions of a relay usually employed in the circuit of the switch for changing over from the vertical. to the rotary movement.
As such circuits are well known in the art, and in view of the fact that the present invention chiefly concerned with the structure of the switch, and with its functions, regardless of other possibilities which may suggest themselves, a detailed discussion of the circuit is omitted.
In order to position the wipers 17 onto stationary terminals of the bank which is not shown for the sake of simplicity, the auxiliary magnet 35is first energized. Its armature 36 is thereby attracted, moving the member 37 toward the detent 31 and supporting the same, and with it the operating pawl 13 in the position, in which it is normally held by the stop 28. It will be observed that the stop 28 is integral with the member 15 provided for the movement in the first direction. Therefore, when the first movement is executed, stop 28 is removed from the position shown in the drawings, relay 35 takes its place during the movement in the first direction, maintaining the pawl 13 and detent 31 out of engagement with the segment 21 as described above.
Hence if the motor magnet 2 is energized, following the actuation of magnet 35, only the operating pawl 12 for the vertical rotary movement can engage the ratchet 16 and thus advance the part 15 and the Wipers 17. The effectiveness of pawl 15 is upon the restoration of armature 5 to its. normal position. It will be seen that member 11 is rotated about fulcrum 7 (Fig. 2) upon the attraction of armature 5 thus lifting pawl 12 into engagement with the next tooth of ratchet 16. Now when armature 5 is retracted, member 11 will have its direction of rotation reversed and as pawl 12 is forced downward, the ratchet 16 will be rotated in a clockwise direction (Fig. 1). Pawl 13 is arranged to operate in the reverse order, that is, move ratchet 22 upon the attraction of armature 5. A further displacement of the wipers 17 in the second direction is then effected by the same motor magnet 2 (after the electro-magnet'35 has been deenergized) by means of the pawl 13, the pawl 12 being then rendered inoperative by the movement of the segment 15 which takes the ratchet 16 out of reach of the pawl 12. This is achieved because pawl 13 for the second direction of movement actuates its ratchet when armature 5 is attracted, while the pawl 12 can only move the part 15 when armature 5 commences to fall back.
\Vhen the selecting device is to be returned toits normal position after a call has been terminated, the driving magnet 2 receives a further. train of impulses of current, thereby advancing part 15 in a vertical direction. This causes the detent 26 to reach a stop 38 attached to the plate 1. The stop 38 lifts the pawl 26 out of the ratchet 16 and releases the displaced part 15. The latter now returns to its normal position with the assistance of springs 24. At the same time, the stop 23 also returns the lever 30 to the point of rotation 29. In this position the lever 30 holds the de tent 31 and the pawl 13 out of engagement with the ratchet 22; hence thespring 25 rotates the segment 21 back to its normal position, thus resetting the selecting device to normal.
The vertical rotary switch shown in Figs. 5, 6 and 7, functions in substantially the same manner as above described for the selecting device with double rotary motion. A brief discussion will therefore suflice. Similarly to the switching device described in the foregoing, this switch is also equipped with an auxiliary magnet serving the same purpose as the magnet of Figs. 1to 4.. This magnet is not shown in the Figs. 5 to 7, inclusive, but its function will be readily understood from the following description.
The designations of the various parts of the switch shown in Figs. 5 to 7, correspond to the designation shown in connection with the switch in Figs. 1 to 1, i. e. like numerals refer to like parts. Where functions are referred to in the following, particularly to Figs. 5 to 7 directed discussion, which are not illustrated in these Figs, reference may be had to corresponding parts illustrated in Figs. 1 to 4.
It will be assumed that two impulses of current are sent to the operating magnet 2 after the auxiliary magnet, not shown, has been energized. This auxiliary magnet acts on a detent (such as 31 in Figs. 1 to 3) and the detent in turn acts on a pawl (such as 13, by means of a member such as 37 in Figs. 1 to 3), maintaining pawl and detent in inoperated position as described. The armature 5, which is mounted at 7 operates the two-armed angular lever 11. However, as the operating pawl 13 for the rotary movement is now out of engagement, the pawl 12 only can operate the ratchet 16 for the vertical movement; hence, the wipers 17 are lifted to the level corresponding to the number of current impulses. When the circuit of the auxiliary electro-magnet is opened, its armature retracts and the member 37, which is fastened thereto, releases the detent 31; the pawl 13 can now operate the ratchet 22 when the motor magnet 2 receives a further number of impulses. I
The release of the selecting device is effected in the same manner as described in case of the double rotary switch, by making the actuation of the detent 31 dependent on the position of the movable part 15, and that of the detent 26 dependent on the position of the part 15 with respect to a fixed stop, which lifts this pawl out of engagement with its ratchet 16. The part 15 is returned to its normal position by means of the tension of the spring 24. The part 15 is rotated back by means of the spring 25. It should also be mentioned that the part 15, which is provided with the teeth 16. is loosely guided in a groove in the shaft 38, while the part 21 having the teeth 22, is rigidly fixed to the shaft 38. The shaft is so mounted in the parts 39 and 40 that it has only rotary movement. It will be readily seen, however, that the switch can easily be so constructed that the shaft 38 is carried along during the vertical and during the rotary setting.
WVhile a specific embodiment of the invention is described and illustrated in the foregoing, it is to be understood that the application of the invention is not intended to be limited thereby, but that all such modifications and variants are contemplated as 'fall fairly within the scope of the following claims.
What is claimed is:
1. An automatic switch comprising stationary terminals, wipers successively movable in two different planes to engage said terminals, two separate pawls for executing said movements, an electromagnet having an armature for controlling said pawls, one of said pawls being effective upon attraction of said armature and the other pawl being effective upon retraction of said armature.
2. An automatic switch comprising stationary terminals and movable wipers, two
to advance said wipers intoengagement with certain of said terminals, two separate pawls for executing said rotary movements, an electromagnet having an armature for controlling said pawls, one pawl effecting one rotary movement upon the attraction of said armature and the other pawl effecting the other rotary movement upon the retraction of said armature.
1. In an automatic switching device, stationary terminals, wipers having a plu rality of'positioning movements executed in succession in a definite sequence to advance said wipers into engagement with said terminals, a plurality of operating pawls, each of said movements being executed by a certain one of said pawls, a common member for controlling said pawls, an electromagnet having an armature, said common member being attached to said armature, one of said pawls being effective upon the attraction of said armature and the other pawl being effective upon the retraction of said armature.
5. In an automatic switch, a plurality of stationary contacts, wipers having a plurality of rotary positioning movements executed in succession in a definite sequence to advance said wipers into engagement with certain of said terminals, each movement being in a difierent plane, a plurality of pawls for executing the plurality of rotary movements, and common electromagnetically controlled means for operating said pawls to execute first one rotary movement then another rotary movement.
6. An automatic switch comprising stationary terminals, wipers successively rotatable in two different planes to engage said terminals, two separate pawls and two separate semi-circular ratchets for executing the two rotary movements, an angular lever having two arms each arm carrying one of said pawls, and an electro-magnet for directly controlling said lever.
In witness whereof, I hereunto subscribe my name this 28th day of December,
PAUL oUAssoWsKi
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