SU1214794A1 - Device for checking set of the surface of textile materials - Google Patents

Description

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The invention relates to the textile industry, namely, to devices for controlling surface DORES of textile materials, mainly nonwovens and fibrous substrates.

The purpose of the invention is to increase the accuracy of the control.

Pa drawing presents a block diagram of the proposed device.

The device consists of a power source 1 (a generator of electrical pulses of high duty ratio), through switch 2, connected with blocks 3 of control, each of which includes power amplifier 4. The outputs of the power amplifiers 4 are connected to the corresponding power inputs of the measuring emitters 5, the output of each of which is connected with the corresponding input of the control radiator 6 of the control unit 3. The flat light filters 7 are installed between the measuring radiators 5 and the material to be monitored 8, and the flat light filters 9 are placed between the material 8 and the measuring photodetectors 10

The reference sample 11 is located between the control emitters 6 and the control photodetectors 12. The sample 11 has, by the number of control photoreceivers, 12 (emitters 6) zones (o and $) with different optical density. The outputs of the control photoreceivers 12 and the measuring photoreceivers 10 are connected through the corresponding amplifiers 13 (differential) to the inputs of the recording unit, consisting of a series of on-switch 14, a comparator 1b, and an information converter 1b. Converter 16 output connected to the actuator 17 movement of the reference sample 11.

The device works as follows.

The source (generator) 1 of the power supply through the switch 2, which performs the functions of a scanning element, supplies successively periodic pulses to the power amplifiers 4. These pulses, transformed by measuring 5 and control 6 emitters D, pulsed light fluxes pass through flat filters 7, material 8 and etlny sample 11, respectively,

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Snow pulses transmitted through the monitored material 8, through flat light filters 9, are fed to the photodetectors Yu, The pulses that passed through the reference sample 11 are fed to the control photodetectors 12, the output pulses of the photodetectors 10 have a different amplitude, the value of which depends on the surface density of the monitored material 8, the output pulses of the control photodetectors have a constant amplitude specified by the optical density of the reference sample 1 1.

The measuring and control photodetectors and emitters are under the same operating conditions, so changes in temperature, humidity, and current of power amplifiers equally affect the parameters of these elements and have little effect on the results of measuring the surface density. Impulses from photodetectors 10 and 12

 through differential amplifiers 13 are successively fed to the inputs of switch 14, which operates synchronously with switch 2. Pulses from the output of switch 14, which also serves as an amplifier of the difference signal from the output of amplifier 13, are fed to the input of comparator 15, which converts these pulses to pulses constant amplitude but

35 different durations. The duration of these pulses is determined by the size of the surface density of the controlled material.

Next, the pulses from the output of the comparator 1.5 are fed to the input of the information converter 16, which converts them into a digital code. The Converter 16 may be made in the form of a microprocessor, which produces

45 programmed processing of information on the surface density of the material, its storage and issuance for recording (registration).

In the absence of a controlled material (3 materials in the working area of the photodetectors, or in the case when the material is stationary, an automatic correction of the sensitivity of the measuring photoreceivers can be carried out

gij Yu. In this case, through the transform-H: spruce 16, a signal is sent to the actuator 17, for example, an electromagnet, which in the working area

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photodetectors 12 sets this lonii sample 11 to a new position, for example, (instead of the initial position l).

Received in the mode of control of information by the transducer 16 is processed and the sensitivity of the measuring photodetectors Y is programmed (programmatically). The sensitivity of the photodetectors can be automatically adjusted based on the information received and connected to the corresponding outputs of the transducer 16,

In the case of the output of the parameters of one of the photodetectors from the operating range, the Converter 16 sends a signal for its replacement or repair.

Flat filters 7 and 9 significantly reduce the additional measurement error caused by the offset of the axis of the photodetector relative to the optical axis of the emitter.

Such a shift occurs during fabrication, installation of photodetectors, deformation of elements of the supporting structure, which has considerable dimensions, with changing ambient temperature, aging, etc. When using light filters, as shown by experimental studies and calculations, the optical axis of the photodetector can be displaced by 68 mm relative to the axis of the emitter when the distance between the photodetector and the emitter is 40-60 mm, without significant distortion of the measurement of the surface density of the material, which is observed in the photodetector without light filters. In addition, the use of light filters reduces the background noise in photodetectors caused by external sources of radiation and reduces the possibility of exciting amplifiers, which often occurs when small light intensities occur in this device.

NSHISH. Order 861/40 Circulation 433 Subscription Branch ShSh Satat, Uzhgorod, Project.1, 4

Claims (3)

1. DEVICE FOR CONTROL OF THE SURFACE DENSITY OF TEXTILE MATERIALS, containing a power source, through a switch and corresponding power amplifiers connected to the supply inputs of the measuring emitters located on one side of the plane of movement of the controlled material, on the other side of which are measuring photodetectors, each of which which is connected with the first input of the corresponding amplifier, the output connected to the corresponding input of the registration unit, and For measuring emitters and photodetectors, control emitters and photodetectors installed in pairs one against the other, characterized in that, in order to increase the accuracy of control, it is equipped with a reference sample placed between the control emitters and photodetectors, and the output of each measuring emitter is connected to the supply input the corresponding control emitter, and the second input of each amplifier is connected to the output of the corresponding control photodetector. 2. Device pop. 1, characterized in that it is equipped with a number of measuring emitters and photodetectors with flat filters installed against the output part of each measuring emitter and against the input part of each measuring photodetector. 3. The device according to claim 1, about t lich ayu--. Furthermore, in order to simplify the setup, the reference sample has zones with different optical densities according to the number of control photodetectors and is installed with the ability to move in the direction perpendicular to the optical axes of the control emitters and photodetectors.