Patent GB-737992-A (GB)
Title: Improvements in or relating to computing apparatus
IPC: G06G1/00
Filed: 1950-08-21
Abstract: 737,992. Calculating-apparatus. ROSE, D. Aug. 21, 1951 [Aug. 21, 1950], No. 20694/50. Class 106 (1). Vector computing apparatus comprises, in one form, several markers each movable along a respective straight path representing the direction of a chosen vector, an indicating element movable along a predetermined path by co-ordinating means a distance corresponding to the component, in a common predetermined direction, of the movement of a marker, and means for successively connecting and disconnecting a marker and the indicating element so that the latter is moved according to the sum of the components. In another form, the markers are replaced by a virtual marker represented by the intersection of two perpendicular straight rigid members, each of which may, during adjustment, be coupled to a corresponding indicator. In an apparatus for determining whether the centre of gravity of an aircraft is within certain safety limits, the loads at the various stations in the aircraft are considered as vectors, the components of which in a given direction represent the moments of the loads about a predetermined point in the aircraft. A plate 2, Fig. 2, has a series of radial slots 4 each corresponding with a particular station in an aircraft. A transparent top-plate 6 carries scales 7 of loads and markers 5 slidable in channels beneath the scales. The plate 6 is calibrated for a particular type of aircraft and is secured over the plate 2 with the markers 5 in their innermost positions so that they enter enlarged portions 4a of the slots 4 and may then move along the latter. The markers are set in turn by a bar 11 slidable in a bearing 8 pivoted centrally in the apparatus. The marker to be set is first engaged by aligning a notch formed on the surface of the bar 11 with the marker and then rocking the bar to engage the marker in the notch. Throughout this movement a cam surface formed on the bar 11 holds a pin 18, slidable in a guide for the bar, in a slot in the plate 6 to lock the bar in its selected angular position. At the same time, a cam 31 on the bar 11 depresses a plate 32 which rocks a longitudinally-pivoted latch bar 33. A resilient arm 34 engaged by the latter is thus moved upwardly to grip an endless tape 36 between it and a rigid arm 35. The arms 34 and 35 are carried by a transversely-movable slide 28 carrying a further slide 25 movable in a direction perpendicular to that of the slide 28. A pin 24 on the slide 25 engages a circumferential groove in the bar 11 and a saddle 23 pivoted on the pin embraces the bar 11. The arrangement is such that whenever the bar 11 engages a marker and is moved axially to set the marker, the slide 25 is correspondingly moved and the tape 36 is moved according to the transverse component of the motion. The tape is moved to and fro as the various markers are set and finally a marker 38 carried thereby indicates on a scale 39, which is adjusted by a knob 40 to account for the moment due to the weight of the aircraft, whether the loading is safe. A knob 42 facilitates preliminary adjustments of the tape. According to the Provisional Specification, the markers are held in place by springs and are set by a knob slidable along the bar 11. The knob is operable to render the spring of a marker ineffective for setting purposes and only when it is so connected to a marker, is the tape latched to the traversing slide. In another embodiment, Fig. 5, a disc 106 inscribed with a graduated radius 107 is set according to the direction of a vector. Cross-wires 52, 53, mounted on endless bands 136, 236, are then set by knobs 57, 59 through gears, e.g. 60, 61, so that the virtual marker 105 formed by their intersection moves from the centre of the disc to a point on the radius 107, corresponding with the magnitude of the vector. During this setting movement, the knobs 57, 59 are pressed inwardly so as to drive through mating conical surfaces shafts, e.g. 62, carrying wheels, e.g. 56, on which are mounted endless graduated bands 54, 55 which are visible through slots in the casing and co-operate with indexes 141, 241. Threaded on each shaft 62 is a captive nut 64 which bears an index co-operating with a scale 66 covering a greater range than the corresponding graduated band. The knobs are then withdrawn and the cross-wires zeroized. Other vectors are then entered in a similar fashion. The resultant vector is represented by the two indicated components which may be combined by means of the cross-wires 52, 53. The cross-wires may be replaced by bars connected by a common slide which may be engaged by a marker sliding in a radial slot, or, according to the Provisional Specification on a radius arm, the engagement effecting the locking of each bar to an associated graduated endless band. For indicating the metacentric height of a ship, the scale 39, Fig. 2, may be replaced by a diagram 39a, Fig. 7, which is adjustable by a knob 40a in a direction perpendicular to the movement of the index 38 on the tape 36 according to the total displacement of the ship and cargo.