Patent GB-177895-A (GB)
Title: An apparatus for recording the number of calls made by telephone by a subscriber
IPC: H04M15/30
Filed: 1921-01-14
Abstract: 177,895. Webb, H. J., and Webb, E. Jan. 14, 1921. Counters actuated by revolving mechanism, counters of scoring type with alarms.-A meter ing aparatus for telephone subscribers is contained in a sealed casing and is operable only by the insertion of a detachable key, being locked until the key is inserted. Rotation of the key in one direction only is possible, and a signal is given to the exchange at each rotation. The operating mechanism consists of a cylinder B1, Fig. 5, with an outer cylinder B2 fastened thereon by a pin p which passes through holes in the cylinder B2 and through longitudinal grooves k in the cylinder B. The pin p passes through a piston v2 inside the cylinder B, and through the central rod t. The two cylinders and the central rod are pushed towards the keyhole in the casing by a flat spring S3 and coiled springs S1, S2. The whole apparatus is locked by a pin g on the spring S3 passing through a hole m<0> in a wheel b on the cylinder B1 and by a feather r or the cylinder B2 which projects between the teeth of the cog wheel C actuating the counting mechanism. Insertion of the key presses back the cylinders B1, B2 and the rod and a stud on the key enters a slot in the cylinder B, to turn it and by engaging behind the circular cover-plate W holds the mechanism unlocked. When the key is turned a cog on a collar b2 fastened to the cylinder B, turns the wheels C one tooth and the wheel C turns the' units drum H1, Fig. 1, of the counting mechanism. The wheel C is held at rest by a spring. A projection y2, Fig. 5, on bracket y prevents actuation of the mechanism except when the cylinder B1 is pushed in the correct distance by the correct key. The counting mechanism is of ordinary construction, preferably of the kind in which the units drum H1 and a toothed wheel M are fixed on the shaft and the tens &c. drums H2 &c. are loose on the shaft and actuated through pinions P all on one shaft T. The reading of each drum is displayed behind a window in the casing. Turning the mechanism in the wrong direction is prevented by a spring- pressed pawl and a ratchet wheel fixed to the shaft. The over-running of the mechanism past the maximum is detected bv a holder N on the last drum H5 in which is fixed a card against which is pressed a style Q to record the extent of rotation. Or overrunning might be prevented by a radial peg on the drum H5 contacting with a stop. An audible signal is given to the exchange on the actuation of the mechanism by an insulating cylinder E fastened to the cylinder B2 on which are fixed three longitudinal metal bars at equal intervals. These bars make contact between brushes F to sound a buzzer. On reaching the withdrawal position the key slides along a decline K which leads it to a stop. The whole apparatus is contained in a casing and sealed by means of a seal on a string or wire passing through holes in any bolts which protrude. The interior of the casing is lined with a material which will give indications of any attempt having been made to tamper with the apparatus.