Patent GB-664966-A (GB)
Title: Instrument for recording the time of the beginning and the duration of any operation
IPC: G07C1/08
Filed: 1949-06-30
Abstract: 664,966. Indicating and recording-apparatus. L'AUXILIARE DES CHEMINS DE FER & DE L'INDUSTRIE. June 30, 1949 [March 14, 1949], No. 17362/49. Class 106 (iv). [Also in Group XVIII] Apparatus for recording the time of the beginning and the duration of any operation comprises a clock-driven record surface with small-scale time graduations in the direction it is driven and a stylus controlled by means to release further clockwork at the beginning of an operation for driving the stylus transversely and to return the stylus to inoperative position at the end of an operation and to retain it there so that the duration is recorded on an enlarged scale while the time is indicated by the small scale. The invention is shown diagrammatically in Fig. 9, wherein a stylus e records continuously on a drum a bearing small-scale time graduations d and large-scale time graduations f, the drum a being driven at constant speed by clockwork b in accordance with the small scale and the stylus being driven during each operation at a speed according with the large-scale time graduations. The stylus e is mounted on a rod g sliding in bearings h, i, and, in the intervals between operations, held up against a stop j by a strong spring n against the action of a weaker spring q by means of a lever k acting on an abutment m. When an operation begins a plunger p depresses the lever k and allows the spring q to pull the rod g downwards under the control of escapement mechanism y through rack r, sector s and a one-way pawl and ratchet t, u. As soon as the operation ends the plunger p is withdrawn and the spring n instantaneously withdraws the stylus e to its initial position so that a line is drawn representing against the scale f the duration of the operation while the time it began may be read against the scale d. A particular embodiment comprises a metal case 1, Fig. 1, with cover 4 hinged at 3, preferably provided with a fluid-tight joint 4a, Fig. 2, and locked by a screw 5, Fig. 8, with nut 10 which may be sealed by a wire 11. A glass 15a in the cover 4 has a time scale G<SP>1</SP> covering the duration of an operation, e.g. 40 seconds. Supporting plates 16, 17 for the mechanism are spaced by members 18 and the plate 16 is riveted to brackets screwed through blocks of rubber 24. A cup 30 is rotatably mounted on a drum 29 fixed on the plate 16 and a ring 34 fitted with a bayonet joint to a collar 31 of the cup 30 clamps a disc 35 which carries a record sheet 36 held by small peripheral fasteners, preferably covered on its upper face with a white coating adapted to be removed by the stylus to leave an indelible coloured line and graduated round its circumference with an hour and day scale G<SP>2</SP>. A series of concentric circles C provide another scale. For driving the disc 35 at a speed appropriate to the scale G<SP>2</SP> a gear-wheel 42 is riveted to the back of the cup 30 and is driven through a train of gears from a spring housed in a drum 39. A key for winding the spring is housed in the casing at 46 with a resilient pad 47 pressing it against the cover. Preferably a clock 48 driven by the same mechanism is housed in the cup 30. A stylus 49 is fixed to a blade 50 held by a lever 55 by arcuate slots 51, 52 and screws 53, 54, the lever 55 being resiliently joined to a part 56 fixed to a sleeve 58 rotatable on an. other sleeve rotatable on a shaft fixed to the plate 16. For recording the opening of the case a cam 64 on the cover, Fig. 7, coacts with a pin 66 on a lever 67 provided with another pin 68 which engages a finger 69 on the blade 50 to constrain it against a retracting spring to move as guided by the slots 51, 52 so that the stylus describes a small arc 70. A pointer 71 for co-operation with the scale G<SP>1</SP> is fixed to the sleeve 59 (not shown), and to this sleeve and to sleeve 58 are fixed toothed quadrants 75, 74 which mesh with pinions 77, 76 keyed to a shaft 78. The shaft 78 is secured to a barrel containing a main spring and has keyed to it a ratchet wheel 79 which drives a wheel 82 through pawls thereon under the control of an escapement wheel 87, anchor 86, balance wheel 84 and hair spring 85. A spring 94 stronger than the main spring acts on, a lever 93 fixed to a shaft 92 to which is fixed a toothed sector 91 meshing with a pinion 90 loose on the shaft 78 and carrying an abutment 89 engaging a stop 88 on the ratchet wheel 79, thus preventing the uncoiling of the main spring and consequent movement of stylus 49 and pointer 71. When an operation begins pressure is supplied to a capsule 118 which raises a rod 109, Fig. 2, to bear on a lever 103, Fig. 4, and turn it against the action of a spring 105 about its pivot 104 to lift a push-rod 100, with ball and socket connection, to bear on a surface 99 of the lever 93 to lift it against the spring 94 and so free the abutment 89 from the stop 88 and allow the main spring to drive the stylus 49 and pointer 71. When an operation ends the pressure collapses and the parts return to inoperative position under the action of the return springs. Thus, a record such as D, Fig. 7, is obtained from which the duration and time may be read against the appropriate scales.