Patent GB-1461696-A (GB)
Title: Load survey recorders
IPC: G01R11/00
Filed: 1974-02-04
Abstract: 1461696 Recording apparatus SANGAMO ELECTRIC CO 4 Feb 1974 [19 April 1973]  04970/74 Heading G1J [Also in Divisions G4-6] A load survey recorder, e.g. for recording electrical power consumption as a function of time, comprises, on a front plate 24, a receptacle 28 for a magnetic tape cartridge 29, the receptacle having a capstan 36, Fig. 5 and a pair of reel knobs 32, 33 extending at right angles to the front plate 24, a support arm 30 movable in a plane parallel and close to the front plate 24 between an operative and an inoperative position and carrying a recording head 102 and a pressure roller 120 to co-operate with the capstan 36 when the arm is in its operative position, Fig. 5, and a common rotary drive 200 which runs at a predetermined speed and drives the capstan 36 and a pulse generating means 284-290 which supplies timing pulses to the recording head 102, so that the generation of timing prises is mechanically synchronized with the tape movement. The arm 30 is pivoted at 42 to the plate 24, and pins 52, 53 at its free end engage in an arcuate slot 54 in the plate 24. The arm is of sheet metal, and carries guide pins 100 and 103 for the tape T. The recording head 102 is adjustably mounted on the arm 30. The pressure roller 120 rotates on a shaft 122 carried between independently sprung arms 124, 126 pivoted to a sleeve 134 on a bolt 128 the ends of which carry the pin 52 and a knob 83 respectively. A latch 72, Fig. 4, to retain the arm 30 in its inoperative position has a notch 80 engageable by the pin 52. To release the latch, the arm is moved upwards slightly by the knob 83 sc that the latch moves to the right, Fig. 4, until the pin 52 engages a ramp 82 of the latch. The arm 30 can then be pivoted to its operative position. To insert the cartridge 29, its lower edge is placed between fingers 156, 157 of a catch 146 pivoted at 162 to the plate 24, the catch being in the dotted position, Fig. 3, and the cartridge is engaged with the reel knob 32 and guide pins 40 on the plate 24. A plug 172 in a guide pin receiving hole on one side of the cartridge ensures that the latter can be inserted only one way round. As the cartridge is pressed into the receptacle 28 to seat on pads 207a and shoulders 40a of guide pins 40, the catch 146 snaps into its second stable position due to the action of an over-centre spring mechanism 150. The arm 30 is then swung to its operative position so that the pressure roller 120 presses the tape T against the capstan 36. A stop 171 in the cover 14 of the recorder casing 12 prevents the cover from being closed if the arm 30 is in its inoperative position. An electric motor 200 drives an output shaft 224 via reduction gearing 222. The shaft 224 drives a cam 284 via gears 226, 264, 268 to actuate a snap-action switch 290 to produce the timing pulses. The cam-shaft 266 carries a minute hand 278 movable over a 15 minute dial, and drives an hour hand 274 movable over a 12 hour dial 272. The time can be initially set using a knob 280. The output shaft 224 also drives the capstan 36 via a gear 228, and the reel knob 32 is driven from the capstan via pulleys 234, 236 and a belt 232. A pawl 248 engages teeth 254 on the pulley 236 to prevent back-running of the reel knob 32. The reel knob 33 is connected by a slipping belt 244 to a fixed pulley 242. Timing pulses from the means 284-290 are recorded on one track of the tape T, and pulses from a Watt-hour meter 20, representing power consumed, are recorded on a parallel track.