US1238106A - Automatic switch. - Google Patents

Automatic switch. Download PDF

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Publication number
US1238106A
US1238106A US13187316A US13187316A US1238106A US 1238106 A US1238106 A US 1238106A US 13187316 A US13187316 A US 13187316A US 13187316 A US13187316 A US 13187316A US 1238106 A US1238106 A US 1238106A
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Prior art keywords
brushes
relay
brush
rod
stop
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US13187316A
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Henry P Clausen
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AT&T Corp
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Western Electric Co Inc
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    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01HELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H67/00Electrically-operated selector switches
    • H01H67/02Multi-position wiper switches
    • H01H67/04Multi-position wiper switches having wipers movable only in one direction for purpose of selection
    • H01H67/12Linear-motion switches

Definitions

  • This invention relates to automatic switches for'use with either automatic or semi-automatic telephone exchange systems.
  • sets of terminals are assembled in vertical rows in a large flat-faced bank or panel over which brushes'are al-.
  • connection from a'calling subscriber to an idle trunk line, whichtrunk may lead either to a selectorswitch or to an operators position.
  • a feature of the invention is the'provision in a gravity Operatedswitch of mechanical stops for arresting the brushes on" an idle trunk.
  • Another feature of this'invention is the arrangement of the terminals 1 I of the telephone lines.
  • Figure 1 shows a side elevation of two of the switches in position to engage contacts, on opposite sides of the same panel board;
  • Fig. 2 is a'section' on line 2-2 of Fig. 1, showing the brush carrier, brushes, bank contacts and line rods;
  • Fig. 3 is a frontelevation on the line 3-3 A of Fig. 1, showing a trunk bar broken away 45 mounted side by side in'groups of any de- Application ma November 17, 1916. I Serial No. 131,873.
  • a switch is placed beforeeach setofcontacts and. comprisesthe following parts: a vertical rod held at either end between plates, a rod slidably mounted on said vertical rod and a brush holder fixed at the upper end of the hollow rod. Teeth are cut in this hollow sliding rod and two holding pawls'ada'pted to engage theteeth are provided. One pawl is controlled by a linearelay and'normally'engages the teeth to hold the switch in its top position.
  • the brush carrier has a trip rod which exarein position to be engaged when their associated trunks are idle, but are tipped'back out'of the way as soon as their trunks be- Adjacent to each row of bank contacts is minal of a subscribers line.
  • the line relay pulls up, dishuman under the attraction of gravity. WVhen' an idle trunk is reached, the brush tripper is engaged by the cross bar, the brushes are The brushes now connect each terminal contact-with its adjacent line rod. and the object of the invention has been accomplished.
  • the stepping magnet is intermittently energized to return the structure to its normal position, and the trunk bar is returned to its normal position ready to stop the next falling switch.
  • a frame 100 is provided to hold each group of switches with its associated Fixed to the frame 100 and gaging its pawl from the sliding rod which to a similar frame at the bottom of the switches, are the plates 101 and another of similar design not shown. These plates are provided with holes for receiving the fixed vertical rods 102 on which slide the hollow rods 103., At the upper end of each rod 103 is a brush holder l04'carrying the brushes 200, 201, 202, 203, 204 and 205. At the upper end of each rod 103 is a brush holder l04'carrying the brushes 200, 201, 202, 203, 204 and 205.
  • each plate 113 On each plate 113 are mounted relays LB, 00 and RR and the magnet SM of a switch.
  • the relays CO and RR may be mounted on the same core to save space.
  • a portion 110 of each plate 113 is bent at right angles to the plate and a hole is cut in the bent portion to allowthe passage of the rod 103 through it; but to keep said rod in its proper relation to pawls 114 and 115 of relay LR and magnet SM, respectively.
  • Pawl 114 is normally held in engagement with teeth 109 by spring 116, but may be disengaged by catch 117, which upon energization of the relay LR is-pulled up by armature 118 of said relay. Armature 118 is provided with an arm and roller 119 for operating its contact springs 120. Pawl 115 is normally held away from the teeth 109 by pin 121 but is pushed against said teeth by spring 122 when armature 123 of magnet SM is pulled up.
  • the trunk bars 300 extend horizontally across a group of switches and are placed so as to engage in their forward position trip rod 106 of brush carrier 104 when the switch is released.
  • an arm 304 At either end oteach bar 300 is an arm 304 which is pivoted on a pin 305.
  • These pins 305 are held in plates 309 which are themselves secured to plates 310, one of which is provided ateach end of the group of switches.
  • each bar 300 Near the end of each bar 300 is attached a lug 301 which is engaged by arm 302 of armature 306 of the relay 403.
  • the bars 300 are held in normal position by springs 307 but when relays 403 pull up they are tipped back so that edges 308 will allow trip rod 106 to pass unobstructed.
  • A. bar 300 is shown in its tipped position in dotted lines in Fig. 1.
  • the relays 403 of which one is provided for each bar are mounted on plate 311 which is located near one end of the bars 300 so as to be out of the way of the switches.
  • brush holder 104 The construction of brush holder 104 will be understood by referring to Fig. 2.
  • the brush end is bent into the shape of a yoke shown at 217, which holds the pin 107.
  • the holder Near the rod 103 the holder is bent to form two horizontal leaves 213. These leaves are cut to fit rod 103 and are fastened to it by clamp 105.
  • An arm 218 extends backward parallel to trip rod 106. At the end of this arm is mounted on pin 215, a stop arm 214 which is held in its normal position by stop 219 and spring 220.
  • the stop arm 214 during the fall of the brush carrier will engage the edge 308 of the first bar 300 which is in its forward position and will bring the brush carrier to a positive stop.
  • the trip rod 216 is also bent to form a yoke at the brush end and is rotatably mounted on pin 107.
  • the contact panel is of usual construction, the contacts and insulated layers being supported'on the rod 125 and held down at the top by a similar rod 128. These rods are held together by vertical rods 124 one of which is provided at each end of the panel and are fastened to the frame as shown or in any well-known manner.
  • the operation of the switch is as fol lows: WVhen the calling subscriber removes his receiver from the hook, line relay LR is energized over the following path: grounded battery, relay LR, wire 9, normal contact of off-normal contact ON, middle contact of relay CO, wires 7, 5, subscribers set, wires 6, 8 to ground over innermost contact of relay CO.
  • the attraction of the armature 118 of this relay disengages the pawl 114 from the teeth of the sliding rod 103, and the brush carrier falls.
  • Off-normal contacts ON are released by pin 108 and a locking circuit for relay LR is closed over wire 10, outermost contact of relay CO, bottom spring of ON to round.
  • Relay 401 being a slow relay does not, however, come up 1m- 1ts front contoure falls back allowing pawl 114 to engage teeth 109, thus supporting the brush carrier.
  • Slow relay 401 becomes energized as soon as relay LR has retracted its armature, and closes at its front contact a circuit for trunk bar tipping relays 403 from ground through resistance vR, front contact of relay 400, front contact of relay 401, relay 403 to bat- Relays 403 now tip back their associated bars 300 preventing their seizure by any other switch.
  • the subscriber is now in connection with an idle operator in the case of a semi-automatic system or with a selec-. tor switch in the case of a full automatic system, and the connection to the called subscriber is completed in the usual manner.
  • Stepping magnet SM being intermittentlyenergized returns the brush carrier to its top position, whereupon the circuit of RR is broken at ON and the switch is stopped. -In passing bars 300, stop arm 214 will not tip them but will itself yield other relays CO or 408.
  • Fig. 5 shows schematically the arrangement of the trunk bars representing a given line before difi'erent panels.
  • the bars repreing interference by him with restoration of senting a given trunk appear at a different level before each panel. If this were not the case, two switches starting simultaneously, one before panel 500 and one before panel 501, would seize the same trunk bar putting the two subscribers in connection with the same trunk.
  • two switches in different groups starting simultaneously cannot seize the same trunk bar, for the bar representing the trunk seized by the first switch will be tipped back. before the second switch reaches it. 1
  • a gravity operated brush carriage adapted to traverse each of said terminal strips, brushes on said brush carriage, horizontally arranged stop members extending across the faces of said terminal strips, one for each level of terminals, said stop members being adapted to arrest the movement of'a falling brush carriage, means controlled by the engagement of a brush carriage with a stop member for moving the brushes thereof into engagement with the corresponding terminals, and means operated upon the engagement of the brushes with the terminals for temporarily removing said stop members from the path of subsequently falling brushes.
  • an automatic switch a plurality of vertically arranged terminal strips, the terminal of each strip being multipled to different levels in the other strips, agravity operated brush carriage adapted to trav-j erse each of said terminal strips, horizontally arranged stop bars extending across the faces of said terminal strips one for each level of terminals, said stop bars being adapted to arrest the movement of a falling brush carriage, and means operated upon the engagement of a brush carriage with a stop barfor temporarily removing the engaged stop bar and the stop bars of the multipled terminals in other strips from the path of movement of subsequentlyoperated brushes.
  • a gravity operated brush carriage adapted to traverse each of said terminal strips, a pluraiity of horizontally arranged stop bars extending across the faces of said terminal strips one for each level of terminals, said stop bars being adapted to arrest the moa ement of a a trip rod yield-j.
  • I group of lines sets of terminals in which said lines terminate, said sets of terminals being arranged in rows, a second group of lines, rods in which said second group of lines terminate, said rods being interspersed between the said terminals and arranged in a direction parallel to said rows of terminals,

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  • Structure Of Telephone Exchanges (AREA)

Description

H. P. )LAUSEN.
- AUTOMATIC SWITCH.
APPLICATION FILED NOV. 17, 1936.
1,238,106. Patented Aug. 28, 1917.
2 SHEETS-SHEET l.
of the panel type, for automatically inter- ,connecting. telephone lines.
'UN T DsT TEs PA ENT OFFICE.
HENRY r. CLAUSEN, or MOUNT VERNON, NEW YORK, ASSIGNOR TO WESTERN ELECTRIC VCOMPAJNY, INCORPORATED, OF NEW YORK, N. Y., A CORPORATION OF NEW YORK.
AUTOMATIC SWITCH.
' To all whom it may concern:
Be it known that I, HENRY P. OnAUsRN, a citizen of the United. States, residing at Mount Vernon, in the county of Westchesis a full',-clear, concise, and exact description.
This invention relates to automatic switches for'use with either automatic or semi-automatic telephone exchange systems. In this type of switch, sets of terminals are assembled in vertical rows in a large flat-faced bank or panel over which brushes'are al-.
. ble to an The ob ect of, this invention is to provide new and improved means for extending a v a' vertical rod,'to which is connected one terlowed to drop in a straight line to the desired set. These terminals are multiplied horizontally across the board to be accessiswitch. I a
connection from a'calling subscriber to an idle trunk line, whichtrunk may lead either to a selectorswitch or to an operators position. 1 A feature of the invention is the'provision in a gravity Operatedswitch of mechanical stops for arresting the brushes on" an idle trunk. Another feature of this'invention is the arrangement of the terminals 1 I of the telephone lines.
Other features of the invention will be apparent from the following.detaileddescription and the appended claims.
Referring to the drawings, Figure 1 shows a side elevation of two of the switches in position to engage contacts, on opposite sides of the same panel board; Fig. 2 is a'section' on line 2-2 of Fig. 1, showing the brush carrier, brushes, bank contacts and line rods; Fig. 3 is a frontelevation on the line 3-3 A of Fig. 1, showing a trunk bar broken away 45 mounted side by side in'groups of any de- Application ma November 17, 1916. I Serial No. 131,873.
It is adapted "come busy.
' tripped and the carriage stops.
1 contact banks.
- Specification qf L t Patent Patented Aug. 28, 1917.
sirable number. A switch is placed beforeeach setofcontacts and. comprisesthe following parts: a vertical rod held at either end between plates, a rod slidably mounted on said vertical rod and a brush holder fixed at the upper end of the hollow rod. Teeth are cut in this hollow sliding rod and two holding pawls'ada'pted to engage theteeth are provided. One pawl is controlled by a linearelay and'normally'engages the teeth to hold the switch in its top position. The
other pawl is actuated by a stepping magnet to return the switch to normal at the com- 1 pletion of the call. In addition to'brushes,
the brush carrier has a trip rod which exarein position to be engaged when their associated trunks are idle, but are tipped'back out'of the way as soon as their trunks be- Adjacent to each row of bank contacts is minal of a subscribers line. When a call is initiated the line relay pulls up, disenfalls under the attraction of gravity. WVhen' an idle trunk is reached, the brush tripper is engaged by the cross bar, the brushes are The brushes now connect each terminal contact-with its adjacent line rod. and the object of the invention has been accomplished. On thecompletion of the call, the stepping magnet is intermittently energized to return the structure to its normal position, and the trunk bar is returned to its normal position ready to stop the next falling switch.
Referring now more specifically to the drawings, a frame 100 is provided to hold each group of switches with its associated Fixed to the frame 100 and gaging its pawl from the sliding rod which to a similar frame at the bottom of the switches, are the plates 101 and another of similar design not shown. These plates are provided with holes for receiving the fixed vertical rods 102 on which slide the hollow rods 103., At the upper end of each rod 103 is a brush holder l04'carrying the brushes 200, 201, 202, 203, 204 and 205. At
. 70 tends 'backward'so asto engage one of a- 100 holds the upper end of plates 113 whose lower end may be held by a similar iron not shown. On each plate 113 are mounted relays LB, 00 and RR and the magnet SM of a switch. The relays CO and RR may be mounted on the same core to save space. A portion 110 of each plate 113 is bent at right angles to the plate and a hole is cut in the bent portion to allowthe passage of the rod 103 through it; but to keep said rod in its proper relation to pawls 114 and 115 of relay LR and magnet SM, respectively. Pawl 114 is normally held in engagement with teeth 109 by spring 116, but may be disengaged by catch 117, which upon energization of the relay LR is-pulled up by armature 118 of said relay. Armature 118 is provided with an arm and roller 119 for operating its contact springs 120. Pawl 115 is normally held away from the teeth 109 by pin 121 but is pushed against said teeth by spring 122 when armature 123 of magnet SM is pulled up.
The trunk bars 300 extend horizontally across a group of switches and are placed so as to engage in their forward position trip rod 106 of brush carrier 104 when the switch is released. At either end oteach bar 300 is an arm 304 which is pivoted on a pin 305. These pins 305 are held in plates 309 which are themselves secured to plates 310, one of which is provided ateach end of the group of switches.
Near the end of each bar 300 is attached a lug 301 which is engaged by arm 302 of armature 306 of the relay 403. The bars 300 are held in normal position by springs 307 but when relays 403 pull up they are tipped back so that edges 308 will allow trip rod 106 to pass unobstructed. A. bar 300 is shown in its tipped position in dotted lines in Fig. 1. The relays 403 of which one is provided for each bar are mounted on plate 311 which is located near one end of the bars 300 so as to be out of the way of the switches.
The construction of brush holder 104 will be understood by referring to Fig. 2. The brush end is bent into the shape of a yoke shown at 217, which holds the pin 107. Near the rod 103 the holder is bent to form two horizontal leaves 213. These leaves are cut to fit rod 103 and are fastened to it by clamp 105. An arm 218 extends backward parallel to trip rod 106. At the end of this arm is mounted on pin 215, a stop arm 214 which is held in its normal position by stop 219 and spring 220. The stop arm 214 during the fall of the brush carrier will engage the edge 308 of the first bar 300 which is in its forward position and will bring the brush carrier to a positive stop. The trip rod 216 is also bent to form a yoke at the brush end and is rotatably mounted on pin 107.
202, 203, 204 and The brushes 200, 201,
205 are fastened to resilient arms 225 and 226 which are held onto holder 104 by bolt 222. The arms 225 and 226 are held apart by insulated washers, and by strips of insulation 223. They are sprung so as to'have a tendency to close together toward the center of the brushes. They are normally prevented from closing by pins 221, carried on the yoke of trip rod 106, which hold them apart. These pins are covered at their lower ends with insulation. When end 216 of rod 106 is raised by contact with a bar 300, the pins 221 are depressed so that the insulated ends are carried below the brushes, allowing the brush arms to spring together and the brushes to rest on the rods 206, 208 and 211 and contacts 207, 209 and 210. In this position of the brushes each contact 207, 209 and 210 is in electrical connection with its adjacent rod 206, 208 or 211. The operation of the trip rod retards the movement ofthe brush carrier and dissipates its momentum.
The contact panel is of usual construction, the contacts and insulated layers being supported'on the rod 125 and held down at the top by a similar rod 128. These rods are held together by vertical rods 124 one of which is provided at each end of the panel and are fastened to the frame as shown or in any well-known manner.
Between the rods 125 and 128 and the panel, plates 127 are inserted. Their projections 224 serve as supports for the line rods 206, 208 and 211, one of which is provided adjacent each row of contacts. These rods may be tightened by nuts 129, one of which is threaded on each rod. To each set of three line rods are connected the terminalsof a subscribers line.
Referring now to the circuit diagram, Fig. 4, the operation of the switch is as fol lows: WVhen the calling subscriber removes his receiver from the hook, line relay LR is energized over the following path: grounded battery, relay LR, wire 9, normal contact of off-normal contact ON, middle contact of relay CO, wires 7, 5, subscribers set, wires 6, 8 to ground over innermost contact of relay CO. The attraction of the armature 118 of this relay disengages the pawl 114 from the teeth of the sliding rod 103, and the brush carrier falls. Off-normal contacts ON are released by pin 108 and a locking circuit for relay LR is closed over wire 10, outermost contact of relay CO, bottom spring of ON to round. The switch falls until end 216 of trip rod 106 is engaged by a bar 300 representing an idle trunk line. The tripping of rod 106 takes up the shock of Stopping the carrier which is positively stopped by stop arm 214, holding against edge 308. The brushes now rest on the contacts of an idle trunk and supervisory relay 400' is energized from grounded battery over tery.
the subscribers line through sluggish supervisory relay 401 to ground. Relay 401 being a slow relay does not, however, come up 1m- 1ts front conture falls back allowing pawl 114 to engage teeth 109, thus supporting the brush carrier.
Slow relay 401 becomes energized as soon as relay LR has retracted its armature, and closes at its front contact a circuit for trunk bar tipping relays 403 from ground through resistance vR, front contact of relay 400, front contact of relay 401, relay 403 to bat- Relays 403 now tip back their associated bars 300 preventing their seizure by any other switch. The subscriber is now in connection with an idle operator in the case of a semi-automatic system or with a selec-. tor switch in the case of a full automatic system, and the connection to the called subscriber is completed in the usual manner.
At the end of the conversation when the calling subscriber hangs up, the circuit for supervisory relays 400 and 401 is broken at the switchhook. Armature of relay 400 in falling back breaks the circuit of relay CO, whereupon restoring relay RR is-energized from grounded battery through the relay, wire 11, back contact of relay LR, outermost contact of relay CO, to ground at bottom contact of ON. Relay RR closes, at its innermost contact, a circuit from ground through the stepping magnet ,SM, interrupter I, to grounded battery. At its middle and outermost contacts, it opens the circuit of the calling subscriber, thus preventthe switch. The subscribers connection with relay LR is also broken by the contacts ON which are not'returned to normal until the switch is ready for the initiation-of another calll Stepping magnet SM being intermittentlyenergized returns the brush carrier to its top position, whereupon the circuit of RR is broken at ON and the switch is stopped. -In passing bars 300, stop arm 214 will not tip them but will itself yield other relays CO or 408.
Fig. 5 shows schematically the arrangement of the trunk bars representing a given line before difi'erent panels. The bars repreing interference by him with restoration of senting a given trunk appear at a different level before each panel. If this were not the case, two switches starting simultaneously, one before panel 500 and one before panel 501, would seize the same trunk bar putting the two subscribers in connection with the same trunk. By the arrangement shown, however, two switches in different groups starting simultaneously cannot seize the same trunk bar, for the bar representing the trunk seized by the first switch will be tipped back. before the second switch reaches it. 1
What is claimed is:
1. In an automatic switch, a plurality of terminal strips, a gravity operated brush to cocpera'te therewith, means for releasing said brush, and a plurality of stop members extending across the faces of said terminal strips arranged to arl es't'the movement of a falling brush.
2. In an automatic switch, plurality of terminal strips, a gravity operatedbrush to cooperate therewith, means for releasing said brush and a plurality of stop members extending across the faces of said terminal strips and arranged to arrest tire movement of a falling brush, and means ontrolled by the engagement of a falling brush with a stop member for temporarily removing said stop member from the path of subsequently falling brushes.
3. In an automatic switch, a plurality of terminal strips, a gravity operated brush carriage adapted to traverse each of said terminal strips, brushes on said brush carriage, horizontally arranged stop members extending across the faces of said terminal strips, one for each level of terminals, said stop members being adapted to arrest the movement of'a falling brush carriage, means controlled by the engagement of a brush carriage with a stop member for moving the brushes thereof into engagement with the corresponding terminals, and means operated upon the engagement of the brushes with the terminals for temporarily removing said stop members from the path of subsequently falling brushes.
4. In an automatic switch, sets of fixed terminals, a plurality of gravity operated brushes arranged to travel over and, make contact with said terminals, means for normally maintaining said brushes inoperative moving said carrier, a brush holder on said carrier, a plurality of brushes for traversingsaid contact sets, resilient arms for uniting said brushes 'to said holder,
normally flexing said arms v to hold the brushes inoperative, a spring pressed stop arm pivotally mounted on said, holder, a plurality of mechanical stops, and means for positioning said stopsto engage said stop arm and trip rod in their travel, said trip rod.
when engaged absorbing the momentum of saidbrush carrier and tripping the brushes and said stop arm when engaged bringing said carrier to a positive stop with its brushes resting on, a set of contacts.
6.1m an automatic switch, a plurality of vertically arranged terminal strips, the terminal of each strip being multipled to different levels in the other strips, agravity operated brush carriage adapted to trav-j erse each of said terminal strips, horizontally arranged stop bars extending across the faces of said terminal strips one for each level of terminals, said stop bars being adapted to arrest the movement of a falling brush carriage, and means operated upon the engagement of a brush carriage with a stop barfor temporarily removing the engaged stop bar and the stop bars of the multipled terminals in other strips from the path of movement of subsequentlyoperated brushes.
7. In an automatic switch, a plurality of vertically arranged terminal strips, the terminal of each strip being multipled to dif- 'ferent levels in the other strips, a gravity operated brush carriage adapted to traverse each of said terminal strips, a pluraiity of horizontally arranged stop bars extending across the faces of said terminal strips one for each level of terminals, said stop bars being adapted to arrest the moa ement of a a trip rod yield-j. lngly mounted on said holder, saidtrip rod falling brush carriage, an electromagnet individual to each stop bar, those magnets associated with barsrepresenting multiples of the same terminal being electrically con nected so as to be energized simultaneously, said magnets when energized removing them associated stop bars from the path of movement of the brushes, and means operated upon the engagement of a brush carriage with a stop bar for energizing said magnets.
8. In an automatic switch, a plurality of.
vertically arranged terminal strips, a plurality of gravity operated brushes adapted to traverse said terminal strips, means for normally retaining said brushes at rest,
means for releasing any one of said brushes,
means for stopping said brush on a selected strip, means operated upon the stoppingpf said brush for actuating said normal retain- 'ing means, and means operated upon the actuation of said retaining means for temporarily removing said stopping means from the path of subsequently falling brushes.
9. In a telephone exchange system, a
I group of lines, sets of terminals in which said lines terminate, said sets of terminals being arranged in rows, a second group of lines, rods in which said second group of lines terminate, said rods being interspersed between the said terminals and arranged in a direction parallel to said rows of terminals,
said rods and said rows of terminals being HENRY P. CLAUSEN.
US13187316A 1916-11-17 1916-11-17 Automatic switch. Expired - Lifetime US1238106A (en)

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