Patent GB-603706-A (GB)
Title: Averaging device
IPC: G01C21/00
Filed: 1944-07-05
Abstract: 603,706. Indicating and integrating apparatus. DEMEULENAERE, M., and DEMEULENAERE, R. July 5, 1944, No. 12832. [Class 106 (iv)] An averaging device comprises a rectilinearly displaceable integrating member, means for imparting at timed intervals to said member a succession of displacements to be integrated, said displacements varying in degree proportional to the magnitude of angular or other variations to be averaged, a time-controlled member displaceable in degree proportional to the progress of time, a primary translating element movable to positions determined by the relative positions of said members and forming an angle with respect to the direction of movement of the time-controlled member, and means movable in degree proportionally to the trigonometrical tangent of said angle to indicate the average variations. As described, the invention is applied to an octant and is used to determine the average of a series of movements given to the regulating knob 11, Fig. 1. The averaging device is connected to the octant by means of a supplemental knob 12 slidable axially of and coupled to the regulating knob 11 of the octant. At the start of the operation the knob 12, Fig. 1, is pushed down until the teeth 15 thereon engage gear-wheel 16 carried by a shaft 17 which has at its other end a gear-wheel 18 meshing with the teeth 22 of a control member 19. A coupling member 26 is normally coupled to the control member 19 by means of a lug 25 on the member 26 engaging in a recess 24 in the member 19, Fig. 9. Thereafter. each rotational movement of the knob 11 is transferred through the pinion 16, shaft 17, pinion 18, control member 19 to control member 26 and by means described later to the integrating screw 21. An integrating member 55 non-rotatably mounted on the screw 21 is thus caused to move up or down distances proportional to the rotation of the knob 11. Clockwork 47 which has been set in motion at the beginning of the operation turns a screw 56 causing a time-controlled member 57 to move therealong distances proportional to elasped time. A pin 72 is rotatably mounted in the member 55 and is movable therewith along a vertical line V, Fig. 1, while a pin 73 fixed to the time-controlled member 57 moves along a line HO. A primary translating element in the form of a rod 74 is attached to the pin 72 and is held in contact with the pin 73 by a spring 76a. The inclination of the rod 74 is therefore varying (a) according to " time " determined by the position of the member 57 on the screw 56 and (b) according to the summation of the angles through which the knob 11 has been rotated, as determined by the position of the member 55 on the screw 21. The inclination of the rod 74 is a measure of the ratio summation of the angles through which the knob 11 has turned elapsed time and is therefore a measure of the average angle at which the knob 11 has been set. This " average angle" is indicated on a scale 77 carried by a pinion 76 which meshes with a gear segment attached to the pin 72. A similar scale 84 is provided and by means of a screw 86, a pinion 88, gear-wheel 89, pinion 16, the knob 12 can be rotated to a position in which the knob 11 is at the average angle. The rotational movements of the coupling member 26 are transferred to the screw 21 as follows. The clockwork mechanism 47 reciprocates a slide 41, Figs. 1, 3 and 4, between guide rollers 42 and it is so arranged that the slide 41 is moving to the left just after the member 26 has been rotated forwardly by the control member 19. The lever arms 48, 49 are caused to swing from the position shown in Fig. 3 to the position shown in Fig. 4 by a cam surface 40 and the coupling member 26 is raised, through the co-operation of a cap 28 and a trunnion 27 integral with the coupling member, until the lug 25 leaves the recess 24 and one of a set of spring teeth 37 on the member 26 engages in one of a set of recesses 36 in a member 32 fixed to the screw 21. The lever arms then swing back under the action of the springs 50, one of the arms 49 striking a pin 51, Fig. 1, on the member 26, so returning the member back to the initial position and so rotating the screw 21. The slide 41 then moves to the right and a spring 34 forces the member 26 downwardly out of engagement with the member 32, the lever arms 48, 49 taking up the position shown in Fig. 1. In this way, the angular movements of the knob 11 are transferred periodically to the screw 21 and as shown above to the member 55.