Patent GB-897433-A (GB)
Title: Improvements in or relating to apparatus for use in reading information recorded on a record
Filed: 1959-07-28
Abstract: 897,433. Relay recording circuits. KIMBALL CO., A. July 28, 1959 [July 29, 1958], No. 25801/59. Class 40 (1). [Also in Group XIX] A record card-sensing device controls the operation of a series of relays for each column of the card the contacts of each series being connected in a recoding network and a test circuit is provided to detect the lack of a path through any of the networks to indicate an error of recording or sensing. The networks are designed to handle recordings in a 4-position (1, 2, 4, 7) code, each digit being represented by one or two perforations, or in a 5-position code which is identical except that a check perforation is added in the fifth position in the case of the single-perforation digits (1, 2, 4 and 7) so that two positions out of the five are always perforated. These codes are respectively called " 4-position unchecked " and " 5-position checked " codes. The records, Fig. 2, which are tags for attachment to merchandize have three rows of columns, making twenty-nine columns altogether, perforated in the five-position checked code. When the 5-position code is being used this is indicated by a special " code-selector " hole CS which automatically adapts the operation of the relay networks for that code the machine can handle tags in either code even when mixed together. The tags are fed from a stack and sensed by a pin-box and the data sensed is punched into record cards as described in Specification 897,426. The sensing pins act through Bowden wires to operate contacts 1, 2, 4, 7 and CBS, Fig. 4, thereby energizing corresponding relays KD1-KD7 and KCB. In addition, the codeselector hole CS controls relay KCS through contact CSS. When this relay is energized, showing that the 5-position code is being used the contacts KCS2-KCS5 transfer so that in order to make a path to the 1, 2, 4 and 7 outputs the check-bit relay KCB must be operated as well, i.e. there must be a hole in the fifth position in the case of these digits to bring the number of holes up to two. In the case of the 4-position unchecked code the relay KCS does not operate, neither does the fifth position relay KCB. Checking.-For a valid recording in each type of card there should be a path from the input lead 332 to one of the outputs 0A-9A. A test is made to detect any network not having such a path, by connecting the input wire 332 of each network to a potential divider controlling in common the grid voltage on a thyratron which is normally biased off. Switches are provided to connect all the outputs 0A-9A of each network to a source of negative voltage which, when a path exists through the network, is transmitted to the lead 332 and serves to keep the bias voltage negative. If any network has an open circuit its input lead 332 is isolated from the negative voltage and the grid bias rises to allow the thyratron to fire. This energizes a relay to stop the machine and prevent the data registered in the relays from being punched into a card. Switches may be provided so that any decoding network can be excluded from this test as desired. Specification 753,063 also is referred to.