GB609306A - Improvements in director or like control systems for guns - Google Patents

Abstract

609,306. Director control systems for guns. FLETCHER, G. H., and METROPOLITANVICKERS ELECTRICAL CO., Ltd. Nov. 10, 1942, No. 15891. [Class 92 (ii)] A fire control system for a gun comprises a device adapted to respond to the relative angular positions of the gun and a director, or other controlling apparatus, the device serving to actuate means adapted to prevent firing when the angular displacement between the gun and director exceeds a predetermined value. In one construction, Fig. 1, the gun and director are mechanically connected to the rotors of selsyn devices 1, 2 respectively,'the stators of the latter being interconnected by conductors 6, 7, 8, and the windings 3, 10 of their rotors being arranged electrically at right angles when gun and director are in alignment. By such an arrangement no voltage is induced in winding 10 when alternating current from a source 4 is supplied to the rotor of device 1 and when the gun is aligned with the director. Under such conditions no current flows through a relay 11, a member of which then bridges a gap between two contacts 12 in the firing circuit. A similar relay 11a is also provided in conjunction with another selsyn device and contacts 12a, one system being associated with the training and the other for elevating movements of the gun. Thus, when alignment is effected and a switch 14 depressed, current from a source 13 energizes a solenoid 15 to effect firing. When misalignment occurs, current flows through relay 11 (or 11a) and breaks the firing circuit. Indicating lamps 16, 17 and cut-out switches are arranged in the circuit as shown. In a modification, Fig. 4, the firing circuit is substantially the same as that in Fig. 1. According to this construction the pointer 25 of an indicator follows, by means of a selsyn device, the movements of the director, while an index finger 40 is mechanically geared to the gun. The pointer and index finger form spark-gap electrodes associated with the secondary winding 45 of a transformer 44, the primary 46 of which is connected to relay 11 and to a power source 47. When parts 25 and 40 of the indicator are well out of alignment, no spark bridges the gap and insufficient current flows through relay 11 to cause it to close the gap between contacts 12. When sparking occurs, however, the gap is closed and the gun may be fired. Further modifications are described in which an indicator and transformer are employed. In another modification, means are employed in association with the selsyn devices for maintaining the gun in alignment with the director. Specifications 592,208, 609,294 and 609,297, [all in Group XXXVIII], are referred to.