SU1312488A1 - Tachometer - Google Patents

Abstract

The invention relates to a technique for measuring non-electric quantities and can be applied when measuring engine speed. The purpose of the invention is to improve the accuracy and efficiency of reading information. At the output of block 1 there is information about the binary code and the number of revolutions of the engine. The combination circuit 6 is the controllable part of the decoder 2 and is constructed so that the signal from the average current change unit 5 is fed to the key that is covered by the signal of the decoder 2 and borders on the public key. The signal from the output of block 5 of the change in average current affects the key to which it is connected, so that the average current through this segment is less than the rated current. If three-output two-color diodes are used in the indicator, the keys can change cooTHoi e- the currents between colors, i.e. By changing the average current, the color of the LED standing between the burning to full brightness and the quenched segments changes. The brightness of the segment is determined by the average current through it, therefore the introduction into the device of the unit 5 of the change in the average current associated with the keys of the indicator 4 and responsive to intermediate speed values, allows to achieve the objective of the invention. 2 hp f-ly, 2 ill. § (L

Description

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The invention relates to the measurement of non-electrical values and can be applied when measuring the number of revolutions of an engine, preferably a vehicle.

The aim of the invention is to improve the accuracy and efficiency of reading information.

 Figure 1 presents the block diagram of the tachometer; figure 2 is an example implementation of the device.

The device contains a rotational speed conversion unit 1 into a code, for example, a binary counter, a decoder 2, indicator control keys 3, a discrete light emitting indicator 4, a unit 5 for varying the average current and a combinational circuit 6. The input of unit 5 is connected to the low-order bit I. Block circuit 6 is the controllable part of the decoder 2, constructed in such a way that the signal from block 5 is fed to the key that is closed by the signal of the decoder 2 and borders on the public key, i.e. is the youngest private key at the moment. The signal from the output of block 5 acts on the key to which it is connected, that the average current through this segment is less than the nominal, for example, the key is opened periodically with some well If, for example, three-output two-color diodes are used in the indicator, the keys can change the ratio of currents between colors, t. e. with a change in the average current, the color of the LED standing between the burning segment at full brightness and fully canceled segments will change.

The device works as follows.

At the output of block 1 there is information in binary code about the number of revolutions of the engine.

However, the input of the decoder does not provide information from all information pdds. The output of the lower bit is connected to the input of the unit 5, the change in the average current. This allows halving the number of indicator segments while maintaining the measurement range. The decoder 2 converts the binary code into a positional code, with the number of burning elements proportional to the speed of rotation of the engine. If, for example, the rotational speed of the motor shaft is intermediate between that

If the third and fourth segments are to be ignited, it is more convenient to record this value not by introducing an intermediate segment,

and a weak burning of the fourth segment, which contrasts with the burning third segment and the non-burning fifth segment and therefore is recorded with confidence. The brightness of the segment is determined by the average current through it. Therefore, introducing into the tachometer a unit for changing the average current associated with the indicator keys and reacting to intermediate speed values (in binary code this will be the least significant bit) improves the accuracy of determining the rotational speed of the vehicle engine, speed of information reading,

the use of a tachometer, which in turn leads to an increase in traffic safety and efficiency of engine control. Control of brightness

as a result of changing the duty cycle of current pulses through the LEDs. The lowest digit of the indicator is the upper LED. With the occurrence of 1 at the output of the lower unit for converting the number of revolutions to the code. This LED begins to shine not at full brightness, since the key controlling it opens periodically (at a frequency higher than the flicker frequency) and the average current is lower than the nominal one. At a higher number of revolutions, when the information at the output of the inverter of the speed into the code leads

To Appearance 1, at the output of the first bit of the decoder 2, the first LED lights up to full brightness as the key controlling it is open all the time. The next LED will light up with intermediate brightness under the condition of 1 at the output of the previous i bit of the decoder and 1 at the output of the lower bit of the speed converter to code, i.e. at an intermediate speed value between the thresholds of full ignition of the first and second LEDs, i.e. changes the contrast of the light transition. In full brightness, the second LED lights up when the appearance of 1 at the second output of the decoder n. Similar considerations are valid for incal or cathodoluminescent inductors, etc. In general, up313

The average current of the LEDs can also be controlled by an excellent 6m of the method shown in the diagram, for example, by supplying power to the required LED through a resistor, etc. Also, the number of gradations of brightness may be more than two, but increasing them is impractical. The use of an indicator whose color of the segments changes with a change in the average current makes it easy to register intermediate values of the measured value, i.e. further increase read efficiency. In addition, the use of multi-color indicators allows the driver to be informed in a timely manner when approaching dangerous engine operation.

Claims (3)

Invention Formula I. Tachometer, containing in series connected pulse date2А884 Speed ticker, speed converter, descrambler, indicator control keys and discrete light-emitting indicator are distinguished by the fact that, in order to increase the accuracy and speed of information reading, a block for changing the average current of the indicator segment is inserted into it the input of which is connected to the younger one. {the information bit of the rotational speed converter to the code, and the output - to the input of the control of the decoder luminance. 2. The tachometer according to claim 1 is also distinguished by the fact that the unit for changing the average current of the segment is made in the form of a pulse generator controlled by the duty ratio. 20 3. Tachometer on ri. 1, which is based on the fact that the indicator segments are made controlled by the color of the glow. &. Editor G. Volkova Compiled by Yu.Mruchko Tehred L. Serdyukov a Order 1967/43 Circulation 777 Subscription VNIIPI USSR State Committee for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab, 4/5 Production and printing company, Uzhgorod, Proektna str., 4 0we.2 Proofreader L. Patay