An improved telemetering transmitter for use with the impulse frequency method

摘要

667,836. Telemetering systems. LANDIS & GYR AKT.-GES. March 22, 1950. [March 30, 1949] No. 7185/50. Class 40 (i). [Also in Group XL (b)] In a telemetering transmitter of the type in which a perforated disc 1 rotates at a speed proportional to the quantity being measured the perforations successively passing light to a photo-cell 11 the output frequency of which indicates the value of the quantity and in which the indications are made directional by rotating a further perforated plate 4 in the light path at a constant speed, to make the instrument more compact the second disc is of less diameter than the measuring disc and is mounted to one side of the measuring disc spindle. The second disc is driven from a synchronous rotor 6 and a fixed "stop" 10 is mounted in the light path. The measuring disc 1. has circular apertures 2 and the constant speed disc has apertures 5 'which are elongated to compensate for the fact that the two sets of apertures are on circles of different radii. The application of the invention to an induction motor meter is described with reference to Fig. 3 (not shown).