SU798915A1 - Device for reading out graphic information - Google Patents

Description

one

The invention relates to automation and computing, in particular, to devices for reading graphic information.

A device for reading graphic information containing a tablet made in the form of two systems of mutually perpendicular coordinate buses connected via current keys to a switch, a coordinate remover connected to serially connected read amplifiers, a threshold element and a control trigger, a coarse determination of coordinates counter, connected to the control unit, the switch and through the logic elements OR (the other input of each of which is connected to the power amplifier) - to the current switches, regis p, connected to the block valve and the read analog converter, a pulse generator, the delay block and a logical AND gate l.

However, this device does not provide high accuracy of reading graphic information and is distinguished by complexity.

The closest to the proposed technical entity is a device containing a tablet made in the form of a system of two mutually orthogonal coordinate buses connected to interrogation valves of coordinate buses, the inputs of which are connected to the control unit and the decoder, serially connected coordinate remover, reading amplifier, threshold element and a control unit, a coordinate counting counter, connected to the control block, a decoder and coordinate output valves, and a counter of the exact coordinate counting, connected. with a coarse count counter of ordinates, a control unit and coordinate output fans, as well as serially connected gates, a register, a digital-analog converter, a power amplifier and logic elements OR, and the control block contains triggers, delay lines, valves and elements OR 2.

five

The disadvantage of the device is its complexity.

The purpose of the invention is to simplify the device,

The goal is achieved by

0 that a device containing a tablet made in the form of a system of two mutually orthogonal coordinate buses connected to coordinate buses interrogating valves, whose inputs are connected to the control unit and to the first decoder, are connected in series to the coordinate remover, readout amplifier, threshold element and unit control, a coarse coordinate count, connected to the control unit, to the first decoder and coordinate output valves, and an accurate coordinate count counter, connected to a coarse count counter the dinat, the control unit and the coordinate output valves, the second decoder connected to the precision coordinate counter, and the current switch, whose inputs are connected to the second decoder, and the outputs connected to the coordinate interrogation valves, are connected; the current switch contains a current source connected , with keys and potentiometers connected in series. The drawing shows the block diagram of the device. The device includes a tablet 1 with coordinate tires, valves 2 and 3 interrogation of coordinate tires, a decoder 4 ,. device input 5, a coordinate remover b, a read amplifier 7, a threshold element 8, a rough counter 9 and a precise coordinate read counter 10, a coordinate output valve 11, a control unit 12 containing a generator 13 clock pulses, a start trigger 14, an X / U trigger 15 , coarse (accurate) trigger 16, 17-pulse pulse valve, 1821 operation valves, OR element 22, delay lines 23 and 24, second decoder 25, current switch 26 containing current control potentiometers 27 in circuits X, current adjustment potentiometers 28 chains x, controllable keys 29, each of which includes a (common) current source connected via an unlocked transistor on the base to the potentiometer 27 (28) of adjustment. The device works as follows. Simultaneously with the removal of the selected point of the tablet 1 by the signal from the input 5, control unit 12 is started. On this signal, the initial installation of the counters 9 and 10 and the trigger 14-16 controls is made. As a result, the clock pulse gate 17 opens, the bus X interrogation valve 18 and the bus counting counter 18 on the counter 9. The decoder 25, in accordance with the initial state of the counter 10, sets up the switch 26 to connect the maximum current source to the valves 2. The first impulse from the valve 20 is fed to the counting input of the counter 9, which from the state 11 ... 1 is set to 00 ... O. As a result, the decoder 4 will prepare for opening the interrogation valve of the first coordinate tire X in block 2. An impulse delayed on the element 24 for the time of completion of transient processes passes the valve 18 using the selected valve in block 2 of the current switch 26 forms the corresponding coordinate bus X pulse current of maximum amplitude. This process of sequential search and excitation of the coordinate tires continues until the moment when the signal is fed to the puller 6 from a nearby tire. Considering the gain on amplifier 7, this signal d is sufficient for triggering threshold element 8, the signal from which, by counting, throws the input, trigger 16 to the precise coordinate measurement mode (valve 20 is locked, since a rough count is received, and valve 21 is opened, serving chain to obtain accurate reference). The next clock pulse from the valve 17 passes the valve 21 and at the counting input sets the counter 10 to the initial state, in accordance with which the decoder 25 sets the switch 26 to connect the minimum current source to the valves 2. The delayed impulse from the valve 18 forms a current pulse of the switched minimum amplitude in the fixed coordinate bus. If this interrogation pulse is not enough to induce an emf of a given threshold level in the puller 6, then the described refinement cycle is repeated, but a larger amplitude interrogation pulse arrives at the selected bus. This continues until induction in the puller 6 emf exceeds a predetermined threshold level. At the same time, the induced signal, the pass-through amplifier 7 and the threshold element 8, are fed to the counting input of the trigger 16, transferring it to the state determining the coarse measurement mode of the coordinate (the valve 20 opens, turns off: the valve 21). The overflow signal of the trigger counter 16 permits the transmission of the X coordinate through the gates 11 to the output of the device, and also flushes the trigger 15 to the measurement mode of the Y coordinate (the valve 19 is opened and the gate 18 is locked), the overflow signal delayed on the delay line 23 the OR 22 element makes the initial setting of the coarse counter 9 and the precision counter 10 for measuring the Y coordinate, starting with the next clock pulse. The second coordinate is measured similarly. Upon completion of the measurement of the coordinate Y, the overflow signal with

the output of the trigger counter 15 resets the trigger 14 of the start, which stops the flow to the unit 12 of the control of clock pulses through the valve 17.

Introduction to the device of the second decoder and switch of currents with new constructive connections allows you to simplify and reduce the cost of the device.

Claims (2)

1. A device for reading graphic information comprising a plate made in the form of a system of two mutually orthogonal coordinate lines connected to interrogation valves of coordinate buses, whose inputs are connected to the control unit and to the first decoder, serially connected coordinate remover, reading amplifier, a threshold element and a control unit, a coarse co-ordinate counter connected to the control unit, to the first decoder and coordinate valves, and a co-ordinate co-ordinator connected to the sc tchikom coarse reference coordinate control unit and rectifiers issuing origin, characterized in that, in order to simplify the device, the device comprises a second decoder coupled to the counter counting the exact coordinates, and a current switch, the inputs of which are connected to the second decoder,. and the outputs are connected to the coordinate bus interrogation valves. 2. The device according to A.1, about t-l and that the current switch contains a source of current connected to serially connected switches and potentiometers. Sources of information taken into account in the examination 1. USSR Author's Certificate No. 4Q7355, cl. G 06 K 11/00, 1974. 2. Authors certificate of the USSR. 517906, class G 06 K 11/00, 1976 (prototype). ff jTT, P, | a-4С1Ж1} - - - ь. f