Patent GB-305990-A (GB)
Title: Improvements in or relating to automatic battery charging systems
IPC: H02J7/14
Filed: 1929-02-11
Abstract: 305,990. Associated Telephone & Telegraph Co., (Assignees of Bellamy, J. I.). Feb. 13, 1928, [Convention date]. Charging and discharging batteries.-In an arrangement in which the flow and cessation of flow of current from a secondary battery to a consuming device, or the operation of a switch between the battery and the device, controls the disconnection and connection of the battery-charger, a relay 24, Fig. 1, stopping charging when the battery is charged to a predetermined voltage has its circuit controlled at 23 by a second relay 14 the circuit of which is prepared when current flows from the battery and is made effective when the current ceases. A contact 7 is controlled by a relay 6 in series in the circuit from the battery to the consuming device or bv a shunt relay in this circuit beyond the switch K or mechanically by the switch K. When current flows from the battery, the contact 7 closes the circuit of a relay 8 the armature 11 of which then completes a locking circuit for the relay 8 through the coil of the relay 14. This coil is short-circuited by the contact 7 until current ceases to flow from the battery, when the contact 7 opens and the relay 14 closes the contact 23. The supply to the battery charger A is closed by contacts 12, 13 when the relay 8 is energized. When the consuming device is the filament circuit of a wireless set, contacts 17, 18 of the relay 14 alternately connect up the batterycharger A and a high-tension battery-eliminator B. After current flow from the battery has ceased and the contact 23 has been closed, the relay 24 closes its contact 26 as soon as the battery is fully or three-quarters charged, the relay 8 then being short-circuited and all contacts being returned to their normal positions as shown. A resistance 10<1> prevents possible short-circuiting of the battery through 7, 26. When the wireless set is supplied by high-tension batteries, three additional relays 8<1> , 14<1>, 24<1>, Fig. 2, corresponding to the relays 8, 14, 24 are controlled by a second contact 10 operated similarly to the contact 7 and control the high-tension battery-charger B. When either battery is sufficiently charged, the corresponding voltage-relay 24 or 24<1> introduces a resistance 21 or 21<1> into the charging circuit before this circuit is broken by de-energization of the relay 14 or 14<1>. The voltage relays are adjustable or in series with an adjustable resistance. The batteries may be periodically overcharged, a push button opening the circuit of the chargestopping relay being provided for this purpose. The chargers when not in use may be disconnected from the batteries. The Specification as open to inspection under Sect. 91 (3) (a) comprises also an arrangement, Fig. 2 (Cancelled), in which a contact 10 is operated with the contact 7 to connect the charger A and the eliminator B alternately to the supply 12, 13, the charge-stopping relay 8 being connected across the battery whenever the contact 7 is closed. If the eliminator is replaced by a high-tension battery, a second voltage-relay acting simlarly to the relay 8 prevents overcharging of the latter battery, and when the relay 6 is energized, the armature 10 disconnects both battery chargers from the supply and the voltage relays are disconnected from the battery circuits. This subject-matter does not appear in the Specification as accepted.