Patent GB-762399-A (GB)
Title: Improvements in and relating to the transmission of indicators of measured values, as from a meteorological sonde
IPC: G01W1/08
Filed: 1954-04-26
Abstract: 762,399. Telemetering. NILSSON, O. F. April 26, 1954, No. 11959/54. Class 40 (1). [Also in Group XXIV] In a telemetering system wherein the magnitude of a variable is periodically translated into a time interval between a reference pulse and a measuring pulse, these pulses are produced by a flat spiral contact segment rotated at constant speed in its own plane, the reference pulse being produced at a fixed position in each rotation of the contact segment, and the measuring pulse at a variable time thereafter dependent on the peripheral point of the contact segment that makes contact with a contact moved in accordance with the variable. Transmitter, Fig. 1. As shown, a meterological sonde A carried, e.g. by a captive balloon, comprises a shaft 6 adapted to be rotated at constant speed by a stepping magnet 7 through pawls 11, 12 and ratchet wheels 13, 14 (see Group XXIV). A radial contact arm 17 on the shaft engages a fixed contact 18 to produce the reference pulses over line 24-25 at a fixed position during each shaft rotation. A spiral contact segment 19 also secured to the shaft engages the nibs 4<SP>1</SP>, 5<SP>1</SP> of the measuring elements 4, 5 of a bimetallic thermometer 2 and a hair hygrometer 3, respectively, at variable times during each shaft rotation, dependent on the temperature and humidity to produce corresponding measuring pulses in the lines 24-25. The measuring pulses flow through a magnet 20 which axially displaces the shaft 6 for a short time so that the nibs 4<SP>1</SP>, 5<SP>1</SP> drop off the side of the contact segment 19 and pass beneath it as the shaft continues to rotate. For this purpose a contact 22 is coupled to the shaft in the axially displaced position thereof and provides a locking circuit for the magnet 20 for a time sufficient to permit the nibs to move clear of the spiral contact 19. Receiver, Fig. 1. A continuously running motor 37 drives the feed roller 33 of a record strip 31, drives an endless film 34 carrying nibs 36 transversely to the record strip 31, and actuates a pulse transmitter 44 feeding the transmitter stepping magnet 7. The reference and measuring pulses actuate a line magnet 50 which through an R.C. circuit energizes a magnet 48, the armature 47 of which rocks a bail 46 forcing one of the nibs 36 against the record strip 31. The temperature and humidity are thus recorded on the strip 31 as a series of marks T, H and read against the reference marks 0. Modifications. In a second embodiment, Fig. 8 (not shown), the transmitter shaft is driven by a synchronous motor in step with the recorder driving motor 37, and the reference and measuring pulses are thermionically amplified before application to the recording magnet. Two contact segments 126, 127, Fig. 9, are used: Contact segment 126 produced the reference pulse when engaged by a fixed contact 128 and a measuring pulse when engaged by the indicator 129 of a hair hygrometer 137-138. Contact segment 127 produces two measuring pulses, one according to the setting of a bimetallic temperature element 140-141 and the other according to barometric pressure or altitude as determined by an aneroid capsule 143. The contact segments are so shaped and positioned on the shaft, and the co-operating contacts so disposed that temperature T and humidity H are recorded on opposite sides of the reference line O, Fig. 10, while the pressure record P may move to either side of the reference line. Constructional details of Fig. 1 transmitter, Figs. 2, 6. The bimetallic strip 65 is linked at 70 to the lever 4 pivoted at 71 and having the nib 4<SP>1</SP> resiliently mounted thereon. The hygrometer elements 66, 67, 68, 69 actuate the arm 5 pivoted at 74 and carrying the resiliently mounted nib 5<SP>1</SP>. The spiral contact segment 19 is carried by a sleeve 82 splined to a shaft 80, Fig. 6, the segment 19 being moved axially on the shaft 80, when the magnet 20 is energized, by the armature-actuated lever 21, which through a push rod 83 also rocks a lever 84 to couple the arcuate contact 22 to a wheel 85 secured to the shaft 80.