Patent GB-812976-A (GB)
Title: Improvements in or relating to electrode recording apparatus particularly for facsimile receivers
IPC: H04N1/191
Filed: 1956-03-12
Abstract: 812,976. Copying-telegraphy. ALDEN, M. March 12, 1956, No. 7641/56. Class 40 (3). [Also in Group XIX] An electrode assembly for recording on electro-sensitive paper comprises two elongated metal or conducting elements each having a rectilinear portion and supported with a thin strip of insulating material so that the rectilinear portions are held in closely spaced insulated relation for simultaneous recording on contiguous areas of the electro-sensitive paper. The arrangement may be used in copying telegraphy to obtain substantially simultaneous recording from the scanning of an original by two photo-cells, e.g. using an additional cell sensitive to red if that tone appears to a marked extent in the original, or to obtain a two-colour reproduction by employing for the linear electrodes metals which give the appropriate colour reactions with the electro - sensitive paper. Alternatively, the coloured traces may be employed to record in the same operation signals representative of variations of a number of physical phenomena. The respective signals representing the values of the physical properties, e.g. temperature and pressure, may be converted to pulses occurring at appropriate corresponding instants during the rotation of a drum having a helical electrode associated with two spaced, but closely adjacent linear electrodes. The sets of pulses may have appreciably different amplitudes so that the traces representing the physical characteristics can be readily distinguished. In one arrangement, Figs. 2 and 3, the linear portions are formed as parallel portions of two metal bands 76, 78 passing around a driving pulley 58 and two idler pulleys 60, 62. The linear portions are electrically insulated from each other by a belt 80 of insulating material passing over the pulleys 58, 60. The pulleys 58, 60, 62 are supported in a frame 54 pivotally mounted at its ends on pins in the side walls of the cover 12 pivoted at 14. The pulley 58 is driven by a motor M, and the idler pulleys 60, 62 are mounted in blocks 66 slidable in a slot 68 in the frame and held in adjusted position by washers and nuts. The linear portions 76, 78 of the electrodes cooperating with the helical electrode 26 of the drum 22 are guided by plates 82, 84 secured to the underside of the frame 54. In the closed position of the cover 12, a curved leaf spring 86 urges the frame 54 downwardly so that the linear electrode edges are in contact with the electro-sensitive paper drawn from the roll R across the platen 24 by feed roller 28 driven through gear trains 38, 39 and 30, 32 from the motor Md driving the drum. In an alternative arrangement, Fig. 6, the linear electrodes are fixed and are formed by the parallel portions of members 90, 96 secured together and to a generally plane portion of a leaf spring 94 fixed to the cover 12. The member 90 is provided with a flange portion 91 engaging a V-shaped groove in a spaced block 92 fixed to the platen portion 24 of the recorder The linear electrode portions are separated by an L-shaped strip 98 of insulating material, and the electrode assembly is pivoted about the block 92, when the cover 12 is raised, by lateral extensions of the channel member 90 engaged by extensions of clips 97 fixed to the sides of the cover.