Patent GB-610829-A (GB)
Title: Improvements in and relating to apparatus for solving vector triangles
IPC: G01P13/02
Filed: 1945-10-10
Abstract: 610,829. Calculating-apparatus. BREWERTON, A. E., and RECORD ELECTRICAL CO., Ltd. Oct. 10, 1945, No. 26377. [Class 106 (i)] Apparatus for solving vector triangles cornprises a member universally mounted, as by a spherical or Hooke's joint type of bearing, for tilting movement in all directions, means for applying to said member to displace it forces whose magnitudes and directions represent those of the vectors to be added, and means for applying a counterbalancing force to said member to restore it and thereby obtain the resultant of the said vectors. In one embodiment of the invention for determining the true wind velocity on a ship, a wind speed transmitter 1, as described in Specification 413,804, applies a voltage proportional to the wind speed to a solenoid 11 and controls a motor 6 which rotates the solenoid to a position corresponding to the wind direction. A force corresponding in magnitude and direction to the relative wind velocity is thus applied by the solenoid 11 to a universally-mounted rod 13, carrying a counterweight 15 and a force corresponding to the velocity of the ship is applied by a roller 23 on a pivoted arm driven by a torque motor 18 which is manually adjusted with the aid of a resistance 25 and voltmeter 26. The direction of the resultant force, and therefore of the true wind, is indicated by means of a forked arm 31 which is carried on a rotatable shaft 30 and caused to follow up the rod 13 by means of a motor 36 associated with contacts on the arm. A transmitter 38, positioned by the forked arm 31 controls an indicator 39. The resultant force is balanced by the attraction of a solenoid 27 on the rod 13 to an armature 33 on the shaft 30, the current supplied to the solenoid being automatically adjusted to the required value by means of a resistance 46 driven by a motor associated with ring contacts 28, 29 on and round the solenoid 27. A voltmeter 40 in circuit with this solenoid can thus be arranged to indicate the speed of the true wind. On an alternative arrangement (not shown), the solenoid 27 and armature 33 are replaced by a fixed solenoid connected to the lower end of the rod 13 by a flexible cable passing over a pulley and through a bore in the shaft 30. In a different embodiment (Fig. 3, not shown), the forces representing the velocities of the wind and ship and balancing force are applied by means of weights, the positions of which are adjusted by means of step-by-step motors. The motor controlling the balancing force is associated with a repeater indicator and the direction of the resultant force is indicated as in the previous embodiment. In a further embodiment (not shown) the force representing the velocity of the ship is applied by means of a spring and the force representing the relative wind velocity is applied by a spring wound by a torque motor which is rotated about the rod in order to apply the force in the correct direction. The resultant force is measured in rectangular co-ordinates by means of springs which are wound up or unwound by motors controlled by two sets of contacts associated with the end of the universally-mounted rod. Transmitters driven by the motors control indicating or recording apparatus or an instrument for converting the rectangular co-ordinates into polar co-ordinates. According to the Provisional Specification, the force representing the relative wind velocity may be applied directly by providing the upper end of the universally-mounted rod with a sphere or vanes and exposing these to the wind.