| 摘要 |
1,008,967. Charging and discharging batteries; systems with selectable sources of supply. SPERRY RAND CORPORATION. Jan. 17, 1963 [Jan. 29, 1962], No. 2093/63. Heading H2H. The D.C. driving motor MR of a shaver apparatus SA is supplied from a transformer/ rectifier power pack PP or from a batter B rechargeable by the pack PP, selection of any one of these three operations being controlled by a single-pole two-way switch KS having an open mid-position and having its two stationary contacts interconnected by a resistor RB. Another resistor RA is connected in series with the primary winding TRP of the transformer TR and in parallel with a circuit defined by the mid-point of the transformer secondary winding TRS and the moving contact of the switch KS. With this contact in position I and shaver SA unplugged from the power pack PP, the motor MR is supplied from the battery B. Should members SA, PP be inadvertently connected in this contact position, the resistors RA, RB respectively reduce the output of pack PP and the current supplied therefrom to members B, MR, thus preventing mal-operation. With the switch contact in position II and members SA, PP connected together, battery B is charged from the pack PP at a current limited by the resistor RB, the resistor RA serving to reduce the output of the pack PP and the current in winding TRP and to reduce the current through the motor MR to a negligible amount. With the switch contact in position III resistor RA is short circuited and the (increased) output of pack PP drives the motor MR, the resistor RB limiting the current through the battery B. Members SA, PP may have a non-symmetrical plug and socket to prevent incorrect connection. For a motor requiring less power, the resistor RA is omitted together with its connections to the switch KS and the mid-point of the winding TRS, Fig. 1 (not shown). |
