SU719932A1 - Device for automatically controlling tensioning of elongate material - Google Patents

Description

I

 The invention relates to tension regulators for long materials, preferably tension regulators when rewinding (winding) film products.

A device for automatically controlling the tension of a lengthy material is known, which contains a speed controller, including a tachogenerator, kinematically connected to the shaft of the electric drive of the material feed mechanism, current controller and control unit connected to the electric drive of the tension mechanism of material 1.

The main disadvantage of the known device is the absence of an adjustable limitation of the rotational speed of the electric drive of the material tension mechanism during a load shedding caused, for example, by a material break, and as a result, the tension control accuracy is insufficient.

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

This goal is achieved due to the fact that the device has a potentiometer and an additional tachogenerator electrically connected with a potentiometer and kinematically with an electric drive of the material tensioning mechanism, two reference elements and an amplifier shunted by a diode, while the inputs of the first comparison element are connected to the outputs of the potentiometer and tachogenerator and its output is connected via an amplifier to the first input of the second reference element, the second input of which is connected to the output of the current regulator, the output of the second element with Equilibrium is electrically connected to the input of the control unit.

The drawing shows blo | - device diagram.

The device consists of a material feeding mechanism 1, a phoning former 2, a storage conveyor 3 and a tension mechanism 4.

Festonizer 2 and transport {storage device 3 in processing lines for processing polymeric and other materials are used as a stock store.

The web feed mechanism 1 is driven by an electric drive 5 fed from an adjustable voltage source 6. Source 6 ex.

Claims (2)

Sx№S / SSS i fK ii; The circuit is closed by a speed feedback and includes a testically connected comparison element 7, a control system 8 and a controlled rectifier 9. The speed tachometer 10 ifo feedback is connected to the comparison element 11. The device for controlling the rotational speed of the electric drive consists of the adjustable current source 12, the control unit 13, which is connected to the controlled rectifier 14, the output of which is connected to the electric drive 15 of the tension mechanism. A negative feedback current potentiometer 16 is connected to an input of a current regulator 17 through a reference element 18. Tachogenerator 19 kbMtr Syer: gTED Fur drive; low voltage and Tachogenerator 10 polymer material feeding mechanism through an element And an oscillator: an amplifier 20, in the capacity of which there may be an individual, depending on the specific conditions, proportional, proportional-integral, or propionally-integral-differential regulators. The input-output amplifier 20 is shunted by a diode 21, vGx6D with 6-line with the element 22 of the comparison., The device operates as follows. To change the wound rolls in a continuously operating line, stop the electric drive mechanism 4 iGat ZhglNY; Include the conveyor-drive 3 and the forming area 2. At the same time, the resulting festo TS on the conveyor until a new pin is installed in the winding device (not shown in the drawing). After that, the conveyor 3, the forcing agent 2 is stopped, the electric drive of the 4 Pieces of the gear is turned on and Bbi6opKa M aTepWM starts In connection with the fact that during normal operation, you can find two driven mecha- nises in the tensioned state (shown in the drawing by the dotted line), a - -jlfiijjf, .5Ke to the ranks can not be STAINED, in the tension mechanism 4 a torque actuator, implemented on the basis of a DC motor, is applied. The torque electric drive is, as a rule, gearless and maintains a fixed torque of the tension mechanism 4 constant. The use of momentum electrification HBOa.a for the purpose of a HYPROP: aET AND IMPACT the reliability of the control system. However, the feature m01 | ей of the electric drive of the electric drive is fixed in TOM, so that when the load is lost, i.e. the tension of the material disappears, the driving electric drive 15 of the tension mechanism 4 is accelerated to the rated speed, it is unacceptable both for technological reasons and safety technique. During the sampling period of the festoons, the speed of the electric drive 15 (the tension mechanism 4 must be greater than the speed of the material feed mechanism 1. In this case, for a given period of time, all the accumulated material between the two drive mechanisms is knocked down and set at a predetermined tension. The control complexity is in that at the end of the sampling process of the scallops, to exclude a sharp jerk of the material, which can cause both deformation and breakage of the material. For this it is necessary that the speed of the torque electric drive 15 is fur when the tension of the material does not exceed the tension of the feed mechanism 1 of the feed mechanism 1 more than the normalized value of 5-20%, depending on the strip material, it should be borne in mind that the specified speed difference in percentage ratio of the two mechanisms should be preserved yo the entire speed control range of the material feed mechanism 1, which can vary within 1:10. To implement a given control law Output signals of tacho generators 10, 19 of feed mechanisms 1 and tension 4 materials Ala are summed allegorically by the comparison element 11 and their difference is fed to the input of the amplifier 20. The system is adjusted so that when the tension of the electric drive of the tension mechanism exceeds the speed of the electric drive of the feed mechanism less than 5-20 / o, the output signal of the amplifier 20 is absent, as it is bypassed diode 21. -. / With the accelerated sampling of festoons, the signal of the tachogenerator 19 begins to increase and when the speed of the electric drive of the tension mechanism exceeds the speed of the electric drive of the feed mechanism more than on the output amplifier varies polarity hold, kofopy in this case the diode 21 is shunted and supplied to a comparing element 22 where algebraically summed with v1ho) 1nym signal current regulator torus. This leads to a decrease in the output signal of the control unit 13 and, accordingly, to a speed limit of the electric drive 15. When the speed of the electric drive of the feeding mechanism 1 changes, the signal of the tacho generator 10 changes and, therefore, the new, limited speed of the electric drive 15 is set. a potentiometer connected to the core of the tachogenerator 19. The feed rate of the material of the mechanism 1 is controlled by changing the input signal Uc at the input of the voltage regulator 6. Constant tension of the strip at different speeds The feed mechanism 1 is set by the input signal UM at the input of the regulated current source 12. Apparatus of the Invention A device for automatically controlling the tension of a lengthy material, comprising a speed controller, including a tachogenerator, kinematically connected to the shaft of the electric drive of the material feed mechanism, current controller and control unit associated with the electric drive of the material tension mechanism, characterized in that In order to increase the control accuracy, it has a potentiometer and an additional tachogenerator. ff-e 7 2 electrically connected to the potentiometer and kinematically with the electric drive of the material tension mechanism, two comparison elements and an amplifier shunted by a diode, while the inputs of the first comparison element are connected to the outputs of the potentiometer and tachogenerator and its output is connected through the amplifier to the first input the second comparison element, the second input of which is connected to the output of the current regulator, the output of the second comparison element being electrically connected with the input of the control unit. Sources of information taken into account in the examination 1. USSR author's certificate in patent No. 2451166 / 28-12, 02.02.77.