US1672517A - Telephone-call recorder - Google Patents

Telephone-call recorder Download PDF

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US1672517A
US1672517A US699739A US69973924A US1672517A US 1672517 A US1672517 A US 1672517A US 699739 A US699739 A US 699739A US 69973924 A US69973924 A US 69973924A US 1672517 A US1672517 A US 1672517A
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station
circuit
recording
key
telephone
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Engelberg Arthur
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    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04MTELEPHONIC COMMUNICATION
    • H04M1/00Substation equipment, e.g. for use by subscribers
    • H04M1/57Arrangements for indicating or recording the number of the calling subscriber at the called subscriber's set

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  • My invention relates to a mechanism for automatically recording telegraphic signals sent over a telephone circuit, such as is shown in my United States Letters Patent No. 1,299,154, issued April 1, 1919.
  • An object of the invention is to provide in a telephonic circuit a telegraphic recording mechanism at a. receivers station adapted tobe operated by a sender at some other station or point of the circuit.
  • Another object of th invention is to provide in a telephonic circuit having an automatic signal recording device at the rethe operation of the DCvers end, means for advising the sender of the operation of the receivers recording device.
  • A. further object of the invention is to provide automatic message recording mechanisms adapted to be operatively connected with a telephone circuit at the sending and receiving stations thereof, whereby du licate messages may be automatically recor ed by said mechanisms upon the sending of a message between said stations.
  • Figure 1 is a side view of a recording mechanism of my invention.
  • Figure 2 is a plan view of the recording mechanism.
  • Figure 3 is a plan view of a key used in device.
  • Figure 4 is a sectional view of the key taken on the line 4-4 in Figure 3.
  • Figure 5 is a diagrammatic view showing the recording mechanism and key operatively connected in a telephone circuit.
  • a device which will record a telephone call when there is no person at the receiving station to answer the same is obviously a*most desirable adjunct to a telephone system. Since such devices must usuall operate without human supervision, their action must be positively assured to the highest possible degree, for their failure to op" a otally secured to the base 8 would defeat the purpose of their installation.
  • the senders and receiver-fa present embodiment of my invention includes a recording mechanism 7 which is mounted on a base 8 and comprises an electromagnet 9 adapted to operate an armature 11.
  • a recording mechanism 7 which is mounted on a base 8 and comprises an electromagnet 9 adapted to operate an armature 11.
  • Fixed to av pivoted arm 12 which is arranged to carry the armature is an extension 13 having at the extremity thereof a point 14 which is adapted to perforate a tape 16 when the armature is actuated by the electromagnet.
  • the tape is carried on a reel 17 suitably mounted on the base 8 and is adapted to be drawn from the reel and over a fixed sup ort and guide member 18 positioned under the point 14 by means of and between cooperating rollers 21 and 22.
  • Rotation of the rollers 21 and 22 may be effected in any desired manner.
  • the roller 22 is mounted on a drive shaft 23 which is actuated by means of a spring operated motor 24 of suitable type.
  • Control of the operation of the clockwork is effected by means of a lock pin 26 carried on a spring arm 27 and adapted to normally register with a perforation 28 formed in a gear 29.
  • the gear 29 is operatively connected to the shaft 23 by means of a pinion 31.
  • Withdrawal of the lock pin 26 from the perforation 28 is efiected by means of an L-shaped lever pivand having arms 32 and 33, the former engaging the spring arm 27 and the latter forcibly engaged and moved by the arm 12 when the latter is depressed.
  • the switch 34 comprises a movable spring member 36 and a cooperatingfixed switch member 37 provided with an adjustable contact point 38.
  • the switch member 36 preferably contacts with the arm 27, thus serving as the means for urging the same toward the gear 29.
  • the edges of the gear perforations 28 are preferably bevelled on the side toward the spring arm so so that as movement of the gear starts upon the withdrawal of the pin by means of the lever arm 32, the bevelled portion of the gear side will engage the pin obliquely and so wedge the spring arm outwardl until such time as the pin bears on the at side of the gear. It will thus be noted that closing of the switch S4 is etfected only during the rotation of the shaft 23 and the consequent operation of the rollers 21 and 22 to draw tape from the reel.
  • a set of recording mechanisms 7 of my invention is diagrammatically shown connected at the two stations 41 and 42 of a telephone circuit having line wires 443 and 44, the telephones. 45 and their connections being indicated in. the conventional manner.
  • the senders key 47. at station 41 is shown depressed, and primes are used with the numbers of the parts to indicate corresponding parts at station 42.
  • the key 47 is so constructed, and is here shown so arranged in the circuit, that the closing of the key at the senders station operates two parallel circuits using the ground as a common return. ()ne of said circuits includes the electromagnet-coils of both recording mechanisms, while the other circuit includes the switch 34 at the receivers station and a signal lamp 48 at the senders end. In this manner, depression of the senders key will first effect the release of both sp ing motors 24 to cause the tapes to be drawn beneath the perforating points, and further depressions of the key will cause perforations to be made in the tapes in synchronism with the operation of the key.
  • a suitable switch 49 is provided which is adapted to break the ground circuit at the receiving station when the tape no longer passes over the support 18.
  • Such switch is preferably, as here shown, mounted on the support 18 and is normally held closed by contact with the tape. the absence of the tape being adapted to cause the displacement of one of the switch members to break the circuit. It will thus benoted that failure of the lamp to flash in synchronism with the operation of the key 47, will be a positive indication of an incomplete operation of the recording mechanism at the receivers station and the sender is thus warned against sending a message which will not be recorded.
  • the key 47 comprises a base 49 on which is mounted a key lever 50 which is adapted to simultaneously touch a pair of contact points 51 and 52 when in normally raised position and a pair of contact points 53 and 54 when in depressed position, the lever 50 being a conductor.
  • the lamp 48 is preferably mounted on the key base 49, the key and lamp being electrically connected to the rest of the device through an extension cable 60 containing the necessary number of conductors. In this manner the key and lamp are adapted'to be placed at such distance from the recording mechanism as will bring them close to the telephone instrument in readiness for use in case a sender receives no answer to his telephone call.
  • the telegraphic circuit will lead from a battery 35 at station. 41 to contact 53, through key lever 50, to and through the coils of the recording mechanism 7, through a conductor 55 to the line wire 43, through an exchange switchboard 56, through the line wire 43 and conductor 57 to the recording mechanism 7, th rough the armature of the mechanism 7' and to the key lever 50, through contact 52 and conductor 58' to ground and thence back to battery 35.
  • the signal lamp circuit branches from the telegraph circuit through contact 53, thence leads through the lamp 48 and conductor 59 to the line wire 44, through switchboard 56, through the line wire 44 and conductor 61 to the switch 34 which has closed on account of the starting of the clockwork, thence to the key lever 50 where it rejoins the telegraphic circuit. Since the arrangement of the various switches and the recording mechanisms at each station is identical, it will be obvious that the system here described is reversible in operation. It will be further understood that by repeated depression of the senders key in accordance with any suitable telegraphic code, a message, such as a telephone after sending ceases. By closing a normallyopen switch 63 in a shunt circuit 64 provided between the terminals of the electromagnets, the operation. of the senders recording device may be prevented without affecting the remaining operations of the device.
  • the tape is preferably marked with some distinguishing symbol such as the words Wind Clock at appropriately spaced points along its length. In this manner, the receiver will be warned to keep the spring motor wound to insure the reception of messages.
  • the device of my invention is particularly applicable to telephone systems of the self-switching or automatic type, and that since in telephoning only alternating currents traverse the line wires, no interference with the functioning of the telephones will result. Since the ground and the two line wires of a telephone system to ether make three telegraphic circuits available, it will be understood that the exact circuit arrangement-here shown is not the only one by which the desired result may be accomplished.
  • a message recordin system comprismg a self operated r-ecor ing mechanism at a distant station adapted to record a telegraphic signal, a sounder at said station adapted to be actuated in accordance with said signal and arranged to actuate said recording mechanism, and an inaudible signal operated directly by said recording mechanism for positively indicating the operation thereof at the sending station.
  • a recording mechanism at said stat1on adapted to record said signals, a key at the senders station for sending said signals, and visible and inaudible signal means at the senders station operated in synchronism with said impulses by the recording mechanism at the receiving station for positively indicating the operation of the recording mechanism.
  • a recording mechanism for electrical comprising an elcctro-magnet impulses
  • a recording means operatable by movement of the lever, record tape arranged to be contacted by said recording means, a normally inoperative motor adapted to draw said tape through said recordmg means, means operatable by said lever for temporarily releasing said motor, and a signal lamp at the station of the sender operatable by said motor releasing means for indicating the operation of said mot-or.
  • a recording mechanism for electrical impulses comprising an electro-magnet, a lever arranged to be actuated by the magnet, a recording means actuated by the lever, record tape arranged to be contacted by said recording means, a motor for feeding the tape from the reel, a wheel rotated by the motor and having a recess therein, a s ring arm having a lock pin thereon normal y engaged in said recess to prevent the operation of the motor, a pivoted releasing lever engaging with said s ring arm and arranged to be operated y said first lever to withdraw the lockpin from said motor wheel recess to temporarily release the motor, and a contact switch operated by said motor releasing lever while the motor is operating.
  • a telegraphic circuit having a senders station and a receivers station, an automatic recording mechanism at the receivers station, an elec tric'signal circuit associated with and operable independently of said telegraphic circuit.
  • a signal arranged in said signal circuit at the senders station, a record tape arranged to be drawn through said recordiiigauechanism, and a switch arranged in said signal circuit and adapted to be actuatcd by said recording mechanism to prevent the closing of said signal circuit when no tape is in position to have messages recorded thereon.
  • an automatic recording mechanism at the receivers station a record tape arranged to be drawn through said record ing mechanism, a normally inoperative releasable motor associated with said recording mechanism and arranged. to draw said tape therethrouglnan independcnt signal circuit between said stations. a switch in said signal circuit adapted to be actuated to cause the closing thereof by and upon the operation of said motor, and a second switch in said circuit. arranged to prevent closing of said circuit when said tape is removed from operative relation to the mechanism.

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  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Indexing, Searching, Synchronizing, And The Amount Of Synchronization Travel Of Record Carriers (AREA)

Description

June 5, 1928. 1,672,517 1 A. ENGELBERG TELEPHONE CALL RECORDER Filed March 1'7, 1924 INVENTOR;
/MW,- 9 GD: ATTORNEY,
Patented June 5, 1928.
UNITED'STATES PATENT OFFICE;
"""Aitrnua ENGELBERG, or OAKLAND, cannronma- TELEPHONE-CALL, nnconnnn.
Application filed March 17, 1924. Serial No. 890,739.
My invention relates to a mechanism for automatically recording telegraphic signals sent over a telephone circuit, such as is shown in my United States Letters Patent No. 1,299,154, issued April 1, 1919.
An object of the invention is to provide in a telephonic circuit a telegraphic recording mechanism at a. receivers station adapted tobe operated by a sender at some other station or point of the circuit.
Another object of th invention is to provide in a telephonic circuit having an automatic signal recording device at the rethe operation of the ceivers end, means for advising the sender of the operation of the receivers recording device.
A. further object of the invention is to provide automatic message recording mechanisms adapted to be operatively connected with a telephone circuit at the sending and receiving stations thereof, whereby du licate messages may be automatically recor ed by said mechanisms upon the sending of a message between said stations.
The invention possesses other objects and features of advantage, some of which, with the foregoing, will be set forth in the following description of the preferred form of my invention which is illustrated in the drawings accompanying and forming part of the specification. It is to be understood that I do not limit myself to the showing made by the said drawings and description, as I may adopt variations of the preferred form within the scope of .my invention as set forth in the claims.
Referring to said drawings:
Figure 1 is a side view of a recording mechanism of my invention.
Figure 2 is a plan view of the recording mechanism.
Figure 3 is a plan view of a key used in device.
Figure 4 is a sectional view of the key taken on the line 4-4 in Figure 3.
Figure 5 is a diagrammatic view showing the recording mechanism and key operatively connected in a telephone circuit.
A device which will record a telephone call when there is no person at the receiving station to answer the same is obviously a*most desirable adjunct to a telephone system. Since such devices must usuall operate without human supervision, their action must be positively assured to the highest possible degree, for their failure to op" a otally secured to the base 8 would defeat the purpose of their installation.
In accordance with the above mentioned requirement of such recording devices,*'I have provided recording mechanisms only record messages'inidu the senders and receiver-fa present embodiment of my invention includes a recording mechanism 7 which is mounted on a base 8 and comprises an electromagnet 9 adapted to operate an armature 11. Fixed to av pivoted arm 12 which is arranged to carry the armature is an extension 13 having at the extremity thereof a point 14 which is adapted to perforate a tape 16 when the armature is actuated by the electromagnet. The tape is carried on a reel 17 suitably mounted on the base 8 and is adapted to be drawn from the reel and over a fixed sup ort and guide member 18 positioned under the point 14 by means of and between cooperating rollers 21 and 22. Rotation of the rollers 21 and 22 may be effected in any desired manner. As here shown, the roller 22 is mounted on a drive shaft 23 which is actuated by means of a spring operated motor 24 of suitable type. Control of the operation of the clockwork is effected by means of a lock pin 26 carried on a spring arm 27 and adapted to normally register with a perforation 28 formed in a gear 29. The gear 29 is operatively connected to the shaft 23 by means of a pinion 31. Withdrawal of the lock pin 26 from the perforation 28 is efiected by means of an L-shaped lever pivand having arms 32 and 33, the former engaging the spring arm 27 and the latter forcibly engaged and moved by the arm 12 when the latter is depressed. In this manner, release of the clockwork and consequent operation of the rollers 21 and 22 is efiected upon exciting of the electromagnet by a direct electric current. withdrawal of the lockpin 26 from the perforation 28. releases the clock work. Since the side of the gear prevents a return movement of the pin until a perforation 28 again,
being adapted to be since the resulting registers with the pin 26, the tape will drawn continuously under the point 14 dur-'--I ing a; period of time radialposition of the perforation 28, the length of are between said perforat1ons,end
t the rotative speed of the gear.
determined by the Movement of the spring arm 27 also serves to close a contact switch 34 which is mounted on the base 8. The switch 34 comprises a movable spring member 36 and a cooperatingfixed switch member 37 provided with an adjustable contact point 38. The switch member 36 preferably contacts with the arm 27, thus serving as the means for urging the same toward the gear 29. To insure closing of the switch 34 only while the gear 29 is rotating and at the same time prevent contact between the lever arm 83 and the arm 12 during such rotation, the edges of the gear perforations 28 are preferably bevelled on the side toward the spring arm so so that as movement of the gear starts upon the withdrawal of the pin by means of the lever arm 32, the bevelled portion of the gear side will engage the pin obliquely and so wedge the spring arm outwardl until such time as the pin bears on the at side of the gear. It will thus be noted that closing of the switch S4 is etfected only during the rotation of the shaft 23 and the consequent operation of the rollers 21 and 22 to draw tape from the reel.
In Figure 5, a set of recording mechanisms 7 of my invention is diagrammatically shown connected at the two stations 41 and 42 of a telephone circuit having line wires 443 and 44, the telephones. 45 and their connections being indicated in. the conventional manner.
For convenience in understanding the operation of the circuit, the senders key 47. at station 41 is shown depressed, and primes are used with the numbers of the parts to indicate corresponding parts at station 42.
v The key 47 is so constructed, and is here shown so arranged in the circuit, that the closing of the key at the senders station operates two parallel circuits using the ground as a common return. ()ne of said circuits includes the electromagnet-coils of both recording mechanisms, while the other circuit includes the switch 34 at the receivers station and a signal lamp 48 at the senders end. In this manner, depression of the senders key will first effect the release of both sp ing motors 24 to cause the tapes to be drawn beneath the perforating points, and further depressions of the key will cause perforations to be made in the tapes in synchronism with the operation of the key. Closing of the circuit through the lamp 48 is completed only upon the operation of the recording mechanism at the receivers station to close the switch 34, thus the lighting of the lamp 48 at the senders station is a positive indication of the operation of the clockwork. To also provide warning if the tape at the recci\ei"s station, because of breakage or exhaustion of the supply, ceases to be drawn beneath the recording point, a suitable switch 49 is provided which is adapted to break the ground circuit at the receiving station when the tape no longer passes over the support 18. Such switch is preferably, as here shown, mounted on the support 18 and is normally held closed by contact with the tape. the absence of the tape being adapted to cause the displacement of one of the switch members to break the circuit. It will thus benoted that failure of the lamp to flash in synchronism with the operation of the key 47, will be a positive indication of an incomplete operation of the recording mechanism at the receivers station and the sender is thus warned against sending a message which will not be recorded.
As here shown, the key 47 comprises a base 49 on which is mounted a key lever 50 which is adapted to simultaneously touch a pair of contact points 51 and 52 when in normally raised position and a pair of contact points 53 and 54 when in depressed position, the lever 50 being a conductor. For the convenience of a user. and as here shown, the lamp 48 is preferably mounted on the key base 49, the key and lamp being electrically connected to the rest of the device through an extension cable 60 containing the necessary number of conductors. In this manner the key and lamp are adapted'to be placed at such distance from the recording mechanism as will bring them close to the telephone instrument in readiness for use in case a sender receives no answer to his telephone call.
Assuming that the sender has depressed the key at station 41, and the key at station 42 is in normal position, as indicated in Figure 5, the circuits will be as'follows: The telegraphic circuit will lead from a battery 35 at station. 41 to contact 53, through key lever 50, to and through the coils of the recording mechanism 7, through a conductor 55 to the line wire 43, through an exchange switchboard 56, through the line wire 43 and conductor 57 to the recording mechanism 7, th rough the armature of the mechanism 7' and to the key lever 50, through contact 52 and conductor 58' to ground and thence back to battery 35. The signal lamp circuit branches from the telegraph circuit through contact 53, thence leads through the lamp 48 and conductor 59 to the line wire 44, through switchboard 56, through the line wire 44 and conductor 61 to the switch 34 which has closed on account of the starting of the clockwork, thence to the key lever 50 where it rejoins the telegraphic circuit. Since the arrangement of the various switches and the recording mechanisms at each station is identical, it will be obvious that the system here described is reversible in operation. It will be further understood that by repeated depression of the senders key in accordance with any suitable telegraphic code, a message, such as a telephone after sending ceases. By closing a normallyopen switch 63 in a shunt circuit 64 provided between the terminals of the electromagnets, the operation. of the senders recording device may be prevented without affecting the remaining operations of the device.
To insure the rewinding of the spring of the clockwork, the tape is preferably marked with some distinguishing symbol such as the words Wind Clock at appropriately spaced points along its length. In this manner, the receiver will be warned to keep the spring motor wound to insure the reception of messages.
It will be noted that the device of my invention is particularly applicable to telephone systems of the self-switching or automatic type, and that since in telephoning only alternating currents traverse the line wires, no interference with the functioning of the telephones will result. Since the ground and the two line wires of a telephone system to ether make three telegraphic circuits available, it will be understood that the exact circuit arrangement-here shown is not the only one by which the desired result may be accomplished.
I claim:
I. In combination with a recording mechamsm for telegraphic signals, means operated by the sender of the signals for causing the operation of the recording mechanism, and an independent signal lamp circuit closable by said mechanism for indicating to the sender the operation of the recording mechanism. 2. A message recordin system comprismg a self operated r-ecor ing mechanism at a distant station adapted to record a telegraphic signal, a sounder at said station adapted to be actuated in accordance with said signal and arranged to actuate said recording mechanism, and an inaudible signal operated directly by said recording mechanism for positively indicating the operation thereof at the sending station.
3. In combination with a sounder for indicating telegraphic impulses at a receiving station, a recording mechanism at said stat1on adapted to record said signals, a key at the senders station for sending said signals, and visible and inaudible signal means at the senders station operated in synchronism with said impulses by the recording mechanism at the receiving station for positively indicating the operation of the recording mechanism.
4;; A recording mechanism for electrical comprising an elcctro-magnet impulses,
be energized by said impulses, a
adapted to lever adapted to be actuated by the magnet. a recording means operatable by movement of the lever, record tape arranged to be contacted by said recording means, a normally inoperative motor adapted to draw said tape through said recordmg means, means operatable by said lever for temporarily releasing said motor, and a signal lamp at the station of the sender operatable by said motor releasing means for indicating the operation of said mot-or.
5. A recording mechanism for electrical impulses, comprising an electro-magnet, a lever arranged to be actuated by the magnet, a recording means actuated by the lever, record tape arranged to be contacted by said recording means, a motor for feeding the tape from the reel, a wheel rotated by the motor and having a recess therein, a s ring arm having a lock pin thereon normal y engaged in said recess to prevent the operation of the motor, a pivoted releasing lever engaging with said s ring arm and arranged to be operated y said first lever to withdraw the lockpin from said motor wheel recess to temporarily release the motor, and a contact switch operated by said motor releasing lever while the motor is operating.
6. The combination with a telegraphic circuit having an automatic recordmg mechanism at the receivers end thereof of a second circuit including a lamp at the senders end arranged to be closed during the operation of the first circuit whereby the sender may be visually advised of the operation of the recording mechanism.
7. In combination with a telegraphic circuit. automatic recording mechanisms at the sending and receiving stations thereof whereby duplicate message may be automatically recorded by said mechanisms upon-the sending of a message between said stations and the operation of the recording device at the receiving sation will be indicated at the sending station independently of the recording mechanism thereat.
8. In combination with a telegraphic circuit having a senders station. and a receivers station, an automatic recording mechanism at the receivers station, an electric signal circuit associated with and operable independently of said telegraphic circuit, a signal arranged in said signal circuit at the senders station, and means operata-ble by said mechanism at the receivers station to close said signal circuit only during the operation of said recording mechanism.
9. In combination with a telegraphic circuit having a senders station and a receivers station, an automatic recording mechanism at the receivers station, an elec tric'signal circuit associated with and operable independently of said telegraphic circuit. a signal arranged in said signal circuit at the senders station, a record tape arranged to be drawn through said recordiiigauechanism, and a switch arranged in said signal circuit and adapted to be actuatcd by said recording mechanism to prevent the closing of said signal circuit when no tape is in position to have messages recorded thereon.
10. In combination with a telegraphiccircuit having' a senders station and a receivers station, an automatic recording mechanism at the receivers station a record tape arranged to be drawn through said record ing mechanism, a normally inoperative releasable motor associated with said recording mechanism and arranged. to draw said tape therethrouglnan independcnt signal circuit between said stations. a switch in said signal circuit adapted to be actuated to cause the closing thereof by and upon the operation of said motor, and a second switch in said circuit. arranged to prevent closing of said circuit when said tape is removed from operative relation to the mechanism.
In testimony whereof. I have hereunto set my hand at Oakland. California, this 15th day of February, 1924.
' ARTHUR EN GELBERG.
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