Patent GB-191422906-A (GB)
Title: Improvements in and relating to Telephone Call Recorders.
Inventor: MCGAURAN DUNCAN JAMES
IPC: H04M15/30
Filed: 1914-11-23
Granted: 1915-10-07
Abstract: 22,906. McGauran, D. J. Nov. 23. Meters and metering systems.-A sub-station metering-device for registering the number of calls made by a subscriber is so arranged that it does not operate until a predetermined time has elapsed after the receiver has been removed from its arm ; while an arrangement is provided by means of which the subscriber cannot interfere with the operation of the meter. A timing- device is also provided by means of which the called subscriber is not registered against if the call is answered within a predetermined time. In the arrangement shown in Fig. 1, the meter RM is operated by a pawl E mounted on a spring-controlled lever C, C<1>. The lever C is engaged by the bifurcated end B<1> of an arm B attached to the receiver arm A, and it carries a pawl D which engages the wheel W connected to a fly F through gearing GT. When the receiver R is removed from the arm A, the aim B releases the lever C, C<1>, and the pawl E is moved over a tooth of the wheel I in a predetermined time under the control of the spring S and fly F. If the time which elapses between the removal and the replacing of the receiver R exceeds this predetermined time, the wheel I is moved when the receiver is replaced by the action of the pawl E; but if this time has not elapsed, the wheel I is not operated. To prevent the subscriber from interfering with the operation of the meter by periodically depressing the receiver arm A, this arm is locked by a toothed segment 1, Fig. 2, and a pawl 2 mounted on the spring-controlled pivoted armature 3 of a magnet 4 placed in the ringing circuit. When the ringing circuit is energized, the armature 3 is attracted to release the arm A and is held in its attracted position against the action of a spring by means of a pin 7 and a notch 8 in a lever 6, which is released by the arm A when the receiver is removed, thereby locking the arm A in its operative. position. To prevent a called subscriber from being registered against if the call is answered within a predetermined time, a timing-mechanism TM, Fig. 1, released by a magnet X in the calling circuit, is provided, this magnet controlling an arm M, K pivoted at the point L. The lever K engages a lever 0 provided with a catch Q adapted to engage the fly F, and a catch U adapted to engage a catch U<1> on a lever T, T<1>. The end of the lever M engages a wheel N of the timing-device, while the end T of the lever T, T<1> is engaged by the arm B. When the magnet X is energized, the catch Q is placed in the path of the fly F, and the catch U under the catch U<1> and retained in this position until a notch in the wheel N allows a spring to withdraw the lever K. If, however. the call is answered before the lever K is withdrawn, the catch U<1> on the lever T, T<1> engages the catch U on the lever O, and the catch Q is retained in the path of the fly F, thereby preventing the meter RM of the called subscriber from registering. In a modification, the meter is operated electro-magnetically, the circuit of the electro-magnet being closed by the operation of the wheel I. The arrangements may be used in conjunction with the metering - devices described in Specifications 19,220/13, 12,232/14, and 12.233/14.