Patent GB-634705-A (GB)
Title: Improvements in meteorological recording method and apparatus
IPC: H04N1/032
Filed: 1945-12-20
Abstract: 634,705. Typewriters. KAO, C. C. Dec. 20, 1945, No. 34630. [Class 100 (iv)] [Also in Group XL (b)] A printing telegraph receiver or electric typewriter comprises a rotatable and axially-movable drum bearing type-faces arranged in rows, permutation mechanism to control the rotary and axial movement of the drum, by means of three cams fixed to the drum-shaft, each co-operating with a separate plurality of selectable stops, and means to set said mechanism in accordance with the numerical co-ordinates of any desired typeface to select that type-face. A drum 7, Fig. 2, has ten peripheral rows, each of a hundred type-faces. Signals comprising the three digits representing the numerical co-ordinates of the desired type-face are sent from a distant transmitter in a four-unit start-stop code, and are received on two distributers E-1, E-4, Fig. 7. Upon receipt of the start-signal distributer E-1 rotates to feed the incoming mark or space code-elements sequentially to four magnets M1 ... M4 controlling a set of code-bars C-1 selected by the distributer E-4. Upon completion of each revolution, distributer E-1 mechanically steps on the distributer E-4 by one segment so that the next received signal is fed to the magnets of code-bars C-2, C-3 and C-4 in turn. The effect of operating any magnet M1 is to turn its associated code-bar through 180 degrees about its longitudinal axis, and thus present a different arrangement of notches to the operating bars OH, OT, OU, M, N, R or S. Selective energization of the " hundreds " set of magnets M1 ... M4 allows only one of the associated operating bars OH to move into an alignment of slots, and by means of associated linkwork 80, 81, 82, Fig. 2, to project a selected stop 27 into the path of a tooth 33, Fig. 4, of a constantly rotating wheel 31. This wheel is keyed to the type drum shaft 8 and stops the drum as a selected tenth of its periphery is adjacent a type-hammer 60, Fig. 2. Similarly, the succeeding signal selects a " tens " code-bar OT and by means of link-work 86, 87, 88 projects a stop 28 into the path of a tooth 45 of a wheel 44, Fig. 5, at the same time by means of projection 90 and lever 91 releasing the previously-selected stop 27 to allow the drum 7 to rotate again until stopped, by the engagement of the selected stop 28 and tooth 45, when the selected one of its hundred type columns is opposite the printing hammer 60. Similarly, the third digital signal selects a " units " bar OU, Fig. 7, and by means of linkwork, a stop 50, Fig. 2, a cam-wheel (Fig. 6, not shown), shiftable clutch 22, gearing 23, 24, 25, 17 and lead-screw 16, raises shaft 14 and drum 7, until the desired type-face is opposite the type-hammer 60. The three-digit signal is followed by a letter signal to select a " function " bar M, N, R or S, Fig. 7, to effect printing and a single space, printing and a multi-space, printing and no space, or spacing alone, respectively. Thus by sending, in a four-unit code, a signal comprising three digits and a letter, any one of a thousand type-faces may be printed. As described, 43 type-faces print punctuation marks, letters or figures, 200 print individual meterological symbols and the remaining 757 print composite meteorological symbols such as shown in Fig. 18. Each composite type-face comprises four quadrants A, B, C, D and a central section E giving information about general weather, cloud, wind direction, wind velocity and visibility respectively. The stops 27, 28, 50 may instead be selected mechanically or electromechanically by the depression of keys arranged in three rows of ten, 110, 111, 112, Fig. 2, and printing and spacing effected by function keys M, N, R, S. Actuation of the type-hammer 60 presses a recording tape 65 (Fig. 1, not shown) against the desired type-face with' a printing ribbon 63 interposed. After it has left the printing position the symbol printed, on the back of the tape, is optically projected on to a ground glass screen 122 in the front wall of the receiver. The return movement of the typehammer may re-set any operated mechanism in any known manner.