Patent GB-741337-A (GB)
Title: Magnetic statistical data storing device
IPC: G06K17/00
Filed: 1953-07-07
Abstract: 741,337. Magnetic recording and reproducing apparatus. CLEVITE CORPORATION July 7, 1953 [July 25, 1952], No. 18804/53. Class 40(2) [Also in Group XIX] A magnetic statistical data storing device comprises a plurality of sheet-like record members, a drum having a given axial dimension and a given circumferential dimension, a plurality of magnetic heads each having a transverse dimension which is small with reference to the axial dimension of the drum, the plurality of heads being axially displaced in the surface of the drum, means for positioning the drum and a selected one of the record members for a magnetic transducing operation by any one of the heads, an electrical signal-translating means connected to one of the heads, and means for driving the drum to cause the head to scan a given line on the selected record member to effect a magnetic translation of the signal. A plurality of sheet like record members 10, 11, 12, 13 and 14 are mounted in a box 15 and are spring biased so as to return into the box. A drum 20 causes a plurality 'of magnetic heads 21, 22, 23 which are axially disposed in the surface of the drum, so that each head is associated with a particular line of a record sheet. The desired card is withdrawn from box 15 by energising one of the solenoids 25, 26, 27, 28 or 29, each solenoid being associated with a particular card by means of a series of holes and slots so arranged that when the pin 30, for example, engages the hole in card 14 this card is drawn out of the box 15 as shown in Fig. 1, the remaining cards being left behind since all have slots in this position. The actual withdrawal of the desired card is effected by removing the box 15 and remainder of the cards, back to the position shown in Fig. 1 by means of a rack 31 and pinion 32 operated by a motor 33. The particular line in which a reading or recording operation is to take place on the selected card is selected by connecting the desired head 21, 22, 23, &c., to the reading or recording amplifier via the sets of slip rings 38, 38, 40, &c. In order to select the beginning of the portion of the scanned line at which the heads are to be effective the drum 20 may be traversed along the surface of the card by means of a motor 42 and screw 43 driving the platform 44 on which the drum 20 is mounted along slides 45, 46. An arrangement is also provided for wrapping the selected sheet around the drum 20 so as to cause a larger portion of the record member to be affected by the rotating heads 21, 22, 23, &c. This arrangement comprises a rack 50 driven by a motor 51 and pinion 52. The rack 50 carries the solenoids 25-29 and is pivoted about a pin 53 which is suspended from the slide 55 on which the box 15 is mounted. The motor 51 thus drives the sheet 14 from the position shown in Fig. 1 in full line to the position shown by dotted line 56. A means is also provided for adjusting the amount of wrap to be given to the card by means of a limit switch 57 slidable along ways 58, 59 to stop the motor 42 when the drum 20 has been driven along the card to a selected position. The limit switch 57 is manually adjustable along the ways 58, 59 and a suitable scale 60 is provided. Similarly a limit switch 61 is provided, slidably mounted on a, track 62. A control station 70 comprises a number of buttons so that the operator can select first a desired sheet, then select a line to be scanned, and then select the portion of the line to be recorded on, or reproduced from. Thus the control station has five buttons designated sheet or card selector, nine buttons designated head selector and manual adjustments for the limit switches designated drum locator and word group, and additional buttons for controlling the various amplifier connections as shown. In a modification shown in Fig. 3 the sheet-like members are contained on an endless belt 110 which is divided into sections 111, 112, &c. The sheetlike members are driven by the drum 114 via a clutch. The drum 114 contains magnetic recording and reading heads 121, 122, 123, corresponding to those described with reference to Fig. 1 the connections being brought out via slip rings 125 as before. A braking device comprising shoes 133, 134, 135, is also provided to arrest the endless belt 110. at the desired sheet. To select the sheet the plurality of lights are provided mounted on a platform 140 and cooperating with a series of coded holes 150, 151, &c. The light passing through the aperture falls on a group of photocells in a housing 154. A second series of holes 152, 153, operate in similar manner to actuate the braking device 133, 134, 135, by means of the solenoid 137. In order to key any of the heads 121, 122, 123, &c., into the magnetic reading recording or erase circuits during only a portion of the time the selected head is scanning a particular line a light source 155 is provided inside the housing of device 125. This light source illuminates a plurality of photo-cells 156, 157, 158, which are mounted on arms so that each photo-cell is illuminated through an aperture in the structure 125 as it is rotated with drum 114. The arms supporting the photo-cells 156, 157, 158 are stationary in operation, but can be angularly adjusted to any desired position to provide a keying action for the desired portion of the line being scanned by a selected head. The coded holes 110 are based on a, system in which the firsttwo holes of a series of five are used in selecting sheet-like members, 111, 112, &c. The -first and third holes are used in selecting the next sheet-like member. The first and fourth are used in selecting the next and so on. The base material of the cards or sheets may be of non- magnetic material with a magnetic material coating. Also, in a preferred arrangement, each head is effective during only one revolution of a recording operation over a recorded item.