Patent GB-1188660-A (GB)
Title: Data Transmission
Inventor: WARSEWA HANS ROBERT
IPC: B23Q5/22
Filed: 1967-08-22
Abstract: 1,188,660. Programmed control of machines. INTERNATIONAL BUSINESS MACHINES CORP. Aug.28, 1967 [Sept. 5, 1966], No.38670/67. Heading G3N.  Data processing apparatus for blocks of data, each representing a group of data words, each word consisting of a plurality of inter-dependent value data letters, and some of the words of a group having identical letters, in which each block consists of the data letters of the first word of a group together with a control letter representing for how many words the corresponding data letters are identical, the apparatus comprising stores for the data letters of the first word and the control letter and a computing means for computing from the stored data the remaining words of the group under the control of the control letter. For a desired machining programme with respect to equal angular rotations of a workpiece, incremental position valves A and first and second differences B, C, corresponsing to mean velocity and acceleration, respectively, over an increment, are derived by an external inter-polator. The programme record is then prepared with groups of words, each word comprising the A, B and C values and a control value Z indicative of the number of increments over which A, B, C remain constant. Where programmed movement is with respect to a linear movement, the incremental position values are derived for equal linear movements. For continuous path control, the movements of all carriages are externally inter-polated and their A. B. C. values derived and time sequentially interrogated. As shown the prepared programme is read in a data source D Q, comprising a magnetic tape unit and a shift register, from the last stage of which a new word is read out by a recognition circuit LD and transferred into a pre-register VR, which buffers the A. B. C, Z values before they are gated into a main register HR. The main register comprises a group of registers for each of the x, y, z and α axes. The presence of a maximum Z value in the pre-register VR causes a recognition circuit ZMD to initiate transfer of a new word into the main register HR and the initiation of an instruction decoder ID, responsive to word data from the preregister VR. The signals from the decoder ID control a modifier circuit DC, influence a digital position control DR through a latch circuit BB and initiate machine functions through outputs SB. The programme axes values and the measured values, from test value generators MWG are transferred through a complement converter KU, either modified or unmodified, to an adder AD deriving new values A, B, C, Z which are recycled through line rwl to the main register HR. The values in the adder AD are decremented by 1 in response to a signal from the modifier circuit DC under control of the instruction decoder ID. The presence of a minimum Z value in the line rwl is detected by a recognition circuit ZMR to erase the contents of the pre-register VR and cause new values and instructions to be read out from the data source DQ. When during a modifying operation, the transmitted A value does not correspond with the A value computed in the adder AD an error signal is developed by circuit AF which supplies a signal to a circuit STOP closing down the system. The sequential control values A, B, C, from the adder or main register, are stored in registers RAR, AB, ZB and interrogated by a digital control DR by which digital position control signals are generated and fed to a circuit ARU. This circuit comprises a register, a digital-to-analog converter and a timing switch and controls the drives along the x, y,z and α axes of a machine, having quadrature carriages and a turn-table. It is stated that two machines, each being positionable about two axes, may be controlled at one time.