SU1290161A1 - Device for checking linear density of fibrous product - Google Patents

Abstract

The invention relates to a measurement technique of the textile industry. The purpose of the invention is to increase accuracy by ensuring continuity of control of the linear density of the fibrous product. The sensor 1 linear density (LP) of the fibrous product generates a signal proportional to the LP of the fibrous product. The control time sensor 6 is set to a position corresponding to a predetermined length of the material cut. When the button 13 is pressed, the control trigger 12 generates an enable signal for the passage of pulses into the counter of 3 pulses. The counter 3 counts the pulses until, as a result of the counting of the pulses from the output of the sensor 11 of the speed of movement of the material by the counter of 14 pulses, a pulse is formed at the output of the counter 14, which sets the trigger 12 to its initial state. Pulse counting by counters 3 and 14 is stopped. In the case of using a rather coarse analog-digital converter 2, the frequency of the pulses generated by it is the sum of two quantities, one of which is proportional to the LP of the product, and the other is constant and represents some initial frequency corresponding to the zero input signal. By knowing the number of extra pulses, you can use switches 7 and 8 and decoder 10 to provide such a mode of operation of counter 3 that when extra pulses arrive at its input, it overflows and then starts counting pulses, the number of which characterizes the LP of the material being controlled. 3 h. item f-ly, 1 ill. 3 "e (L to; about 9)

Description

The invention relates to a measurement technique of the textile industry.

The purpose of the invention is to increase accuracy by ensuring continuity of control of the linear density of the fibrous product.

The drawing shows a block diagram of the proposed device.

The device contains a linear density sensor 1 of the fiber product, connected to the input of an analog-digital converter 2. The input of the counter of 3 pulses is connected to the output of the element 4, and the output of the counter 3 is connected to the corresponding input of the indicator 5,

The device contains a control unit 6 control time and switches 7 and 8. Counter 3 is made in the form of a chain of RST-flip-flops 9, the counting (T) input of the first of which is connected to the output of the element And 4, and the counting input of each of the other triggers 9 is connected to the output of the previous . The setup inputs R and S of the flip-flops 9 through the decoder 10 are connected to the corresponding switch contacts (OT

the number of triggers 9,

The setting device 6 contains a sensor 11 for moving the fiber product, controlling the RS flip-flop 12, the set S input of which is connected to a power source (not shown) through a start button 13, a pulse frequency divider made in the form of a counter 14, element 15, driver 16 pulse and pre-counter 17.

The outputs of the trigger 12 and the sensor 11 through the element 15 are connected to the inputs of the preliminary counter 17, the output connected to the input of the meter ka 14. The installation input R of the trigger 12 through the switch 7 is connected to the discharge outputs of the counter 14. The output of the trigger 12 is connected the input element I 4 and through the driver 16 - with the installation R-inputs of the counter 14 and with the contacts of the switches 8. The discharge outputs of the counter 3 are connected to the corresponding inputs of the indicator 5,

The device works as follows.

The sensor 1 of the linear density of the fibrous material generates a signal.

proportional to the linear density of the yarn moving relative to sensor 1. This signal is converted by analog-to-digital converter 2

a sequence of pulses whose frequency varies in proportion to the change in the signal at the output of sensor 1, i.e. proportional to the change in linear density of the yarn.

To measure the linear density of the yarn segment of a given length of the control unit 6, the monitoring time is set to the position corresponding to the specified length of the yarn segment, and

button 13 is turned on. In this case, the control trigger 12 is set to a position in which its output signal permits the passage of pulses from the output of sensor 1 to the counting input of the counter 3 pulses, and a short pulse is generated at the output of the pulse former 16 that clears the counters 14 and 17 and depending on the position of the switches 8 and on which of their fixed contacts are connected to the output of the imaging device 16, it arrives or does not arrive at one or another input of the decoder 10. As a result, the number in the counter 3, the code of which cases determined by the position of the switch 7

and the connection circuit of the fixed contacts of the switch 8 with the input

shaper 16.

As the pulses from the analog-digital converter 2 to the counter 3, the number recorded

in counter 3, it is measured. This change continues until, as a result of pulses coming from the speed sensor 11 to the counter 14, the bit output of the counter 14 connected via the switch 7 to the setup input R of the control trigger 12 fails to form a logical unit, which will lead to reset trigger 12 in

the initial state and to the cessation of the arrival of pulses at the counting inputs of counters 3 and 14. At the same time, no pulse is generated at the output of the former 16.

The time interval during which the pulses of the analog-to-digital converter 2 are fed to the counter 3 is determined by the frequency of the sensor 1 1 and the division factor,

312901

The counters 14 and 17, which, in turn, are determined by the position of the switch 7. Thus, by changing the position of the switch 7, the length of the yarn blade can be adjusted, the linear density of which is controlled.

At the end of the time interval formed by the setting device 6, the number O recorded in the counter 3 and indicated by the indicator 5 will be the sum of the number recorded in the counter 3 at the moment the button 13 is pressed, and the number of pulses received by the transmitter 5 2 during the specified interval. When using a fairly simple voltage-to-frequency converter, the frequency of the pulses generated by them is the sum of two quantities, one of which is proportional to the input signal and the other is constant and represents some initial frequency corresponding to a zero or very small input signal. Thus, the number of pulses arriving at the counter 3 during the interval formed by the setting unit 6 will be 30 different from the value proportional to the linear density of the yarn, and the greater, the longer the duration of the specified interval. The value of the initial pulse frequency for 35 single-type voltage-to-frequency converters is approximately the same and can be easily determined. Knowing this value and the operating time of counter 3, it is possible to determine the number of 40 excess pulses arriving at counter 3 due to the nonlinearity of the initial portion of the characteristics of the analogue-digital converter 2, and thus, the number that should be 45 recorded in counter 3 when pressed buttons 13. This number is equal to the difference between the maximum capacity of the counter 3 and the number of extra pulses received by it. 50 In this case, the arrival of pulses on counter 3 from analog-digital converter 2 first leads to overflow and zeroing of counter 3, after which its contents 55 increase again and reach a moment of blocking element 4 and is proportional to the linear density of the yarn and in which

one

there is no error due to the nonlinearity of the initial part of the characteristics of the converter 2. This value is indicated by the indicator 5 at the end of the time interval formed by the setting device 6.

To provide an indication directly in units of linear density (for example, in texas) regardless of the length of the controlled yarn segment between the transducer 2 and the counter 3, it is advisable to turn on a control frequency divider (not shown) equipped with a dividing factor switch interlocked with switches 7 and 8 .

The required number is written to counter 3 by connecting the output of the imaging unit 16 with the corresponding fixed contacts of the switches 8, so that at each position of the switches 7 and 8, when the button 13 is pressed, the corresponding code combination is fed to the inputs of the decoder 10.

When using a sensor whose characteristic has a non-linear initial section, the influence of this section on the measurement results can also be eliminated by appropriately adjusting the numbers recorded in counter 3 before the measurements start.

Claims (3)

1. An apparatus for monitoring the linear density of a fiber product comprising a fiber density sensor connected in series and an analog-to-digital converter, output connected to the first input of an element I, the output of which is connected to a counting input of a pulse counter, output connected to the input of an indicator, controlled trigger trigger, a fiber product movement speed sensor, a key, a pulse frequency divider and a time setting monitor, characterized in that, in order to improve accuracy by the continuity of the liver to control the linear density of the fiber product, the outputs of the sensor for the velocity of the movement of the fiber product and the control trigger through the key are connected to the input of the divider 51 the frequency of the pulses, the bit outputs of which are connected to the corresponding inputs of the control time master, the output associated with the reset trigger of the control trigger, and the second input of the AND element connected to the output of the control trigger, 2. The device according to Claim 1, that is, in order to improve serviceability, it is equipped with a pulse shaper, the input and output of which are connected respectively with the output of the control trigger and the reset; pulses. 3. The device according to claim 1, characterized in that in order to increase accuracy by compensating Editor A.Renin Compiled by B. Kisin Tehred L. Serdyukova Order 7893/39 Circulation 798 Subscription VNIIPI USSR State Committee for Inventions and Discoveries 4/5, Moscow, Zh-35, Raushsk nab. 113035 Production and printing company, Uzhgorod, st. Project, 4 6G .6 error of the nonlinearity of the static characteristics of the linear density sensor of the fiber product and the analog-digital converter, it is equipped with switches, the number of which is equal to the number of pulses of the pulse counter, and the decoder, while the inputs of the decoder are connected to the outputs of the corresponding switches, the control inputs of which connected to the output of the driver, and the outputs of the decoder and associated with the corresponding installation inputs of the pulse counter. 4, The device according to claim 1, characterized in that the installation inputs of the time control knob and switches are combined .. Proofreader L. Patay