The TEXCONTROL RRC “Card Sliver Autoleveller”, is an independent unit placed at the delivery of the card. It acts directly on the sliver through a variable drafting arrangement and not through the card feed. The latter process has a very high inertia and does not enable short term adjustment to be made. The TEXCONTROL RRC is the only type of autoleveller to pro¬duce very short term regularity due to the extremely low inertia of the mechanical parts used in the regulating process.
Only the drafting rollers are controlled by a special variable speed motor. The TEXCONTROL RRC measures the instantaneous variations in sliver weight at the card delivery trough a tongued and grooved roller sensing device, which is unaffected by variations in humidity. This drafting range consists of a pair of feed rollers and a pair of delivery rollers, the latter being driven by a variable speed motor with very low inertia.
The variations in drafting continually compensate the sliver count variation which is measured by the mechanical feeler. The TEXCONTROL RRC corrects the sliver count variations on lengths below 10 cm. (the theoretical limit of adjustment is 2,5 times the average staple length).
The stability of the measuring and calculating components is such that a consistent sliver weight is maintained over very short lengths (below 10 cm) and over very long periods of time (for several weeks without any adjustment to the draft). As the sliver speed varies at the delivery of the TEXCONTROL RRC, the speed of the coiler must also vary. This is obtained through a coiler motor, which is also controlled by the Computer of the TEXCONTROL RRC. Normal stopping and starting of the card has no effect on the autoleveller.
Since 1973 experience has proved that:
Until now, no card sliver autoleveller was capable of adjusting both very short term variations (below 10 cm) and maintaining this over very long periods (over several weeks).
Formerly, very short term regulation was only possible by successive doublings.
Today, thanks to the TEXCONTROL RRC, it is possible to eli¬minate the drawing passages during open-end and conventional spinning.
The TEXCONTROL RRC is independent from the control of the card but acts directly on the card sliver by drafting, and there- by levelling out, any variations.
The TEXCONTROL RRC is placed between the card delivery and the coiler. It is easily fitted to most types of existing cotton cards.
Using the TEXCONTROL RRC, the card sliver can be fed either direct to the speed frame or to the OE spinning frame.
The above characteristics may be modified without prior notice. They are also influenced by the care given in the preparation and by the nature of the raw materials.
This regulator aims at obtaining as constant as possible a sliver title at the outlet of the card. At the outlet of the regulator, constancy of the title is insured as well at short term (below 4 inches) as at long term over several weeks.
Such evenness is ensured whichever the origin of the variations of the sliver or web title at entrance of the regulator.
It thus enables to obtain a sliver title which remains unchanged with respect to the various characteristics of the cotton, defectives of the feed system of the card or the card itself.
A sliver provided by the regulator may be used to feed directly the open end spinning frame or, in the conventional spinning system, to feed directly a special flying frame with a doubling of 4. In both cases, drawing frames are eliminated.
The evenness of the sliver is obtained by giving to the input sliver a variable draft which is a function of the variation of the title of the sliver at the input.
At the input of the regulator, the web which is gathered into a sliver runs between 2 rollers, the upper one is a tongued roller and the lower one a grooved roller. The distance between these two rollers is a function of the instantaneous title of the web.
This distance is transformed by an electronic transducer into an electronic signal. This signal will be used to control the speed of a special motor which drives the drafting rollers in such a way that the draft given to the sliver compensates the title fluctuation. The sliver at the outlet of the drafting roller is thus constant. The speed of the sliver at this point is variable, so it is necessary to control equally the speed of the coiler.
The coiler is driven by an electric motor, the speed of which is controlled by the R.R.C. Between the R.R.C. and the coiler, the sliver runs into a PVC trumpet and makes a loop. The length of the loop turns the position of the trumpet which controls the speed of the coiler. When the trumpet goes down, the speed of the coiler is increased, and if the trumpet goes up, the speed of the coiler is decreased.
There are several adjustments to be made in relation to the quality of the cotton:
On leaving the Works, the R.R.C. is adjusted to work with an input sliver title which is about 5 gr. per metre. The output title depends only on the main draft, given at the sliver, which can be settled on the front panel.
There are safety devices which stop the motion of the card when there are faults in the regulator:
The installation is composed of 3 main parts:
A pair of tongued and grooved rollers (l).
The lower roller is driven directly by the card ; the upper roller is connected by mechanical multiplication to a transducer (5).
The speed of these rollers is measured by the tachometer (6).
These rollers (1) consist both in feeding the rollers of the drafting system and in elemenis of measure of the title of the sliver.
A pair of drafting rollers (2).
The lower roller is driven by a special motor which speed is controlled by the electronic computer. The speed is measured by the tachometer (7).
The upper roller can be disengaged thanks to the handle al the top of the drafting system. At the output of the drafting rollers, the sliver runs into a trumpet which is called loop control. This trumpet has an oscillating motion an its weight is perfectly compensated by a spring, in order to avoid any faulty between the R.R.C. and the coiler.
On the front panel of the loop control there is a switch with 3 positions:
Two pilot lamps which indicate in which position the loop control is placed.
Inside the DRAFTHEAD there is a screw to adjust the zero position of the transducer N° 5. This adjustment will only be used when the input tátle is over 6 gr. per metre, or below 5 gr. per metre. At this moment, the user must cali for an official technician to re calibrate the R.R.C.
The electronic Computer receives its information from:
On the front panel is a meter which indicates either:
There are also 4 other switches:
All active circuits are located on the plugging printed boards.
A complete description of these printed boards is given below.
There are also several adjustments on these printed boards, but only one must be adjusted by the user to adjust the position of the output trumpet N°8. This adjustment is located on the printed board 8 and is not sealed.
Location for Printed board N°2 and N°9 are free.
All force elements are located at the rear of the Computer box on a cooler, in order to avoid heating inside the box.
This unit is directly fixed on the coiler and Controls its speed. The motor is a conventional 3-phase ASYNCHRONE - 1,5 H.P. 220 V AC.
This motor is connected to the frequency inverter, located inside of the Computer box. These work at a frequency in such a way that it adjust the speed of the coiler in a proper manner.
The electric cables ending by a special plug, it is impossible to mix them up.
Printed boards located in the electronic box are numbered from 1 to 10. N°1 IS AT THE RIGHT SIDE AND N°10 AT THE LEFT SIDE.
ONLY PUT THE MAIN VOLTAGE 220 VOLTS AC TO THE RRC TEXCONTROL UNIT WHEN PRINTED BOARDS , DEVICES AND ELECTRIC CABLES ARE AT 100% CONNECTED OTHERWISE DAMAGES MAY BE CAUSED.