| 摘要 |
<p>749,452. Charging batteries. SHARP, J. R., and KAYE, E. May 5, 1954 [May 5, 1953], No. 12438/53. Class 38 (4). [Also in Group XXXVII] A battery charging control device for terminating flow of charging current upon the battery attaining a predetermined voltage corresponding to full charge, comprises a microswitch 36 closed by manual operation of a spring-loaded push-button 33 when charging is to commence and retained in the closed position by a pawl 30 engaging a normally fixed ratchet wheel 27 but which is released to allow the switch to open upon melting of readily fusible metal 25 surrounding a square shaft 26 fixed to the ratchet wheel, melting being caused by the heat developed in a non-linear resistor 20 connected across the battery terminals. The resistor 20 may be in series with an external variable resistor determining the time required for fusion to occur after the attainment of the predetermined voltage. Current is conveyed to the resistor 20 through conductive blocks 16, 17 between which the resistor is clamped by an insulated screw 22. Block 16 has a bore 24 which receives the end of the square shaft 26 and the fusible metal 25. The whole is contained within a moulded casing 11 provided with a thick internal lagging of cork 15, 18, 19. Instead of the readily fusible metal 25, other thermally responsive means, such as a bimetallic strip or a normally magnetic element which becomes non-magnetic when heated, may be employed.</p> |
