| 摘要 |
<p>1438439 Battery chargers MOTOROLA Inc 29 Nov 1974 [18 Jan 1974] 51881/74 Heading H2H Battery charging apparatus adapted for charging different batteries with different charging currents comprises a resistor packaged within the housing for a battery having a value related to the charging current for the battery, control voltage circuitry connected to the resistor and producing a control voltage having a value related to that of the resistor, charging current supply circuitry connected to the battery and including control circuitry for controlling the charging current in accordance with a control voltage applied thereto, and circuitry connecting the control voltage circuitry with the control circuitry to control the battery charging current. In the embodiment shown, the charging current is supplied from a source 21 via transistor 22 and diode 24, the battery 12 to earth at 30. Battery 12 and its resistor 14 are housed at 10 and have terminals 16-18 which co-operate with terminals 26, 30, 40 of a receptacle 28 of the battery charger. The control voltage circuitry comprises two transistors 31, 32, the resistor 14 being connected into the emitter-collector path of transistor 31 to control the current therein and hence to control the potential at the junction of resistors 36, 37 which is connected to the base of transistor 22 to control its impedance. In a modification, Fig. 2 (not shown), an integrated circuit current regulator controls the current through a resistor connected between the supply 20 and the base of transistor 22, and hence the potential at the base of this transistor. A further transistor (90), Fig. 2, may be connected with its base-emitter path in parallel with the diode (24) and have its collector connected to earth via an L.E.D. (92) to provide an indication of whether the charger is on.</p> |
