SU855692A1 - Graphic information reading-out device - Google Patents

Description

one

The invention relates to automation and computing, in particular, to devices for reading graphic information and can be used for the on-line transformation and input into computers of various forms of graphic information.

A device for reading graphic information is known, which includes a tablet with coordinate tires connected to switches, a coordinate remover connected through an amplifier to a trigger, elements AND, OR, a control unit connected to switches, counters and registers 1.

The disadvantage of this device lies in its structural complexity.

It is also known a device comprising a tablet with a matrix of mutually orthogonal coordinate buses, two bus switches connected to the corresponding tablet tires, a clock generator connected to the start button, and an output connected to the bus switchboard, a coordinate remover inductively connected to the coordinate buses and connected through the amplifier-shaper to the input of the first control trigger, the outputs of the first control trigger are connected to the control inputs of the coarse and precise counters, the clock inputs of these with controllers connected to the clock generator, a second control trigger connected to the output of the first control trigger, and outputs connected to the control inputs of the switches.

to

However, this device is characterized by insufficient high accuracy.

The purpose of the invention is to improve the accuracy of the device.

The goal is achieved

15 in that the device containing the tablet, made in the form of a system of two mutually orthogonal coordinate buses connected to the corresponding switches, whose inputs

20 are connected to a pulse generator, and in series a coordinate remover, an amplifier-formaker connected to the element I, the first trigger connected to the element

25 control, a second trigger connected to the switches and c. control element, a reversible counter connected to the first trigger., with a pulse generator, with control elements And 30, and a counter connected

With a pulse generator, with a second trigger, with a control element, with switches and with an And element, a series-connected saw-tooth voltage generator connected to the first trigger, an integral trigger connected to one coordinate bus, an inverter and an adder whose other input is connected to the sawtooth generator, and the output; connected to other coordinate tires tablet.

The drawing shows the block diagram of the device.

The device includes a tablet 1 with coordinate tires, switches 2 and 3, a generator of 4 pulses, containing, a start button 5 and a clock pulse shaping unit 6, a booster amplifier 7, first 8 and second 9 triggers, counter 10, reversing counter And, element II 12, a functional current generator 13 comprising a sawtooth voltage generator 14, an integrator 15, an adder 16 and an inverter 17, a coordinate remover 18, and a control element 19 configured, for example, as a button.

The device works as follows.

Pressing the set button 19 ensures that the triggers 8 and 9 and the coarse counter 10 are set to the zero state, the reversible counter 11 of the exact count is set to the state corresponding to the distance between the tires. At the initial moment of time, the outputs of the functional current generator 13 have a high level of voltage.

With the closure of the button 5, the operation of the node 6 forming the clock pulses is permitted, high potentials at the first outputs of the second trigger

9 and the first trigger 8 allow the passage of clock pulses into the coarse counter 10 and polling the tires X of the tablet 1 through the switch 2 of the buses X. As soon as an 18-coordinate puller induces an emf greater than 0, this emf by the amplifier 7 is amplified and fed to the input the first trigger 8 and puts it into a new state, thereby stopping polling the tires X of tablet 1 via switch 2 of buses X, and in the latter the key allowing polling the bus on which the polling stops and the previous one is stopped counts etchike

10 and it contains information about the coordinate of the selected tire.

The next stage is the specification of the coordinates of the puller 6 coordinates. At the same time, the high potential at the second output of the first trigger B permits the start of the generator 14 of the sawtooth voltage of the functional current generator 13 and the operation of the reversible counter 11.

At the same time, an odd bus out of the selected pair of tires X on the tablet, through the first current output of the generator 13, fails one specific current value, and even even the other.

If the coarse read stop occurred on the odd-numbered tire X of tablet 1, then the odd-numbered tire X of tablet 1, in which the current of the first given value flows, is located to the right of the 18-coordinate remover. The current flowing through the two buses induces an emf whose value is zero for a certain value of X, while the low potential at the output of the first discharge of the counter 10 ensures the operation of the reversible counter 11 for subtraction.

If the coarse reference stop occurred on the even bus X of plate 1, then the right bus is the even plate X plate; that 1 in which the current flows, having another specific value in the puller 18 coordinates. The total current from the two tires X of the tablet 1 induces an emf whose value is zero, with a different value of X. In this case, a high potential; at the output of the first discharge of the counter 10, the reversible counter 11 works on addition, as well as in combination with a high potential on the first the output of the first trigger 8 allows the pulse from the output of the amplifier maker 7, formed at the end of the coarse reference of the coordinates, through the element 12 to transfer the reversible counter 11 to the zero state.

Simultaneously with the interrogation of two tires X of tablet 1 by the functional generator 13, a series of pulses from the clock generator 4 arrives at the reversible counter 11. As soon as the EMF induced in the 18-coordinate puller becomes larger than zero, a pulse is generated at the output of the amplifier 7 that translates the first trigger 8 to the initial state, and the potential drop at the first output of the first trigger 8 transfers the second trigger

9 in the new state, which ensures that the device reads the coordinates of the Y. At the same time, the X position of the puller 18 coordinates on the tablet 1 will be fixed in the sweeper 10 and the reversing counter 11.

The reading of the Y coordinate occurs similarly to the reading of the X coordinate. The only difference is that the high potential at the second output of the second flip-flop 9 allows the switch 3 of the U bus to operate. At the beginning of reading, the voltage level at the second output of the second flip-flop 9 sets the counter to the initial state

10 and a reversible counter 11. The introduction of new units and new structural links allows a significant increase in the accuracy of the device.

Claims (2)

1. US patent 3992579, cl. 178-18, published. 1976. 2. USSR author's certificate number 466522, cl. G 06 K 11/00, 197 (prototype). Gz