Classifications

• • D—TEXTILES; PAPER
  • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
  • D01G—PRELIMINARY TREATMENT OF FIBRES, e.g. FOR SPINNING
  • D01G23/00—Feeding fibres to machines; Conveying fibres between machines
  • D01G23/06—Arrangements in which a machine or apparatus is regulated in response to changes in the volume or weight of fibres fed, e.g. piano motions

Definitions

• a known method measures the cross-section of the slivering belts and regulates the speed of the feed roller of the card based on the measured values obtained in such a way that - even with a different density of the fiber feed - the card is always fed with just as much material per unit of time as to maintain a constant cross-section is required on the trigger. Because of the long fiber transport path between the location (feed roller) and the measuring location on the take-off rollers, this method is relatively slow. Fluctuations that are shorter than this transport route cannot be compensated for, since they have already passed the location at the time of their metrological recording. This method can only be accelerated if the measuring location is brought closer to the location.
• a well-known measuring device in this category measures variations in fiber throughput by optically determining the fiber covering density, for example on the reel.
• the method is based on the fact that, for example, a light fiber covering reflects more light with increasing density than the dark background formed, for example, by the drum set.
• This measuring organ technical progress Although the required one is an essential difference in the reexxion properties of the fiber covering and background, it means a limitation of the applicability. Another limitation is the decreasing accuracy with poor fiber resolution. This hinders, for example, the optimal use of this measuring element on the licker-in, although from a control point of view this would represent the optimum measuring location for card feed regulation with a closed control loop.
• the present invention relates to a method and a device with the same intended use as this optical measuring element, but without the restrictions described above, according to the features defined in the claims.
• the above-described card draw-in regulation with a closed control loop can be made faster, more accurate and more universal than was possible with the previously known techniques.
• the method according to the invention is based on the torque of the licker-in drive being measured and a signal which corresponds to this torque being used as a control variable for regulating the pulling-in speed of the carding machine. Since a substantial part of the licker-in torque depends on the amount of material supplied to the licker-in per revolution, variations of this torque can be used as a measure for the cross-sectional fluctuations of the fiber template to be compensated. In order to compensate for such fluctuations, in the simplest case only the speed of the feed roller needs to be regulated so that the torque of the licker-in remains constant, ie the licker-in operates at constant speed with constant tear output.
• the tear output essentially depends only on the amount of material supplied per unit of time, which, while neglecting short power peaks with the same material and the same tear output, applies at least within a limited period of time, this means that the card is at least within the stated period limited time intervals, a constant amount of fibers per unit of time is fed. Since this amount of fiber is drawn off at the card exit at a constant speed, this also means that the cross-section of the coil remains constant. The purpose of regulation is thus fulfilled.
• the tear performance of the licker-in generally depends not only on the material throughput, but also different pre-dissolution of the fibers, different finishings, differences in moisture etc. can have a significant influence on the specific tear performance.
• the licker-in also requires a considerable idling torque that is independent of the tearing power in order to overcome the bearing friction and the air resistance, and here too over longer periods of time. Fluctuations can be expected.
• the torque measurement on the licker-in is advantageously combined with an absolute measuring element on the gimbal trigger, which is suitable for correcting long-term inaccuracies in the torque measurement.
• the torque measurement method can also be used in the same way on the reel, in which case it is not the tearing power but the carding power of the cover that is recorded.
• the cross-section of the fiber covering on the reel can be regulated and ultimately the volume number. Long-term differences are also advantageously corrected here by combining them with an absolute measuring element on the card take-off.
• a modified method is also conceivable, in which the control signal is obtained from the torque behavior of the feed roller. Pulling the cotton into the card requires a torque that increases with increasing cotton thickness. The desired constant fiber throughput can then be achieved by regulating the feed roller speed in opposite directions. This method can also be combined with the direct tape measurement already described.
• the device according to the invention for carrying out the method essentially consists of a device for measuring the torque on the licker-in or on the reel or on the common drive of these two elements and a known draw-in regulation of the card with a closed control loop. Based on the description and the figures, execution examples of the invention are explained in more detail.
• 1 shows schematically a card with a control device
• Fig. 4 details of a third
• Fig. 5 details of a fourth variant of the control device.
• the in the. Fig. 1-3 schematically shown card consists in a known arrangement of the feed roller 1, the fiber material is presented, the licker 4, the reel 8 with fiber covering 7 and lids 9, the customer 11 with the Ab Spotifywal zen 12, the calender part 13 and the pitcher 16.
• the individual rotating bodies with individual drives are shown, namely the feed roller 1 with a motor 3, the licker-in 4 with a motor 5, the reel 8 with a motor 10 and the doffer 11 with a motor 1b.
• Calender part 13 and can 16 are driven by a mechanical connection 28 from the customer 11.
• the torque of the licker-in 4 is measured by means of the current consumption of the motor 5.
• the current is proportional to the torque; with an AC motor, the current I x cos is proportional to the torque.
• the motor current I is converted into a proportional U by means of a measuring resistor 6 and compared with a setpoint voltage in a first summation point 17.
• the difference ⁇ U resulting from this comparison is converted in a control element 20 into a control signal U R for the speed of the motor 3 or the feed roller 1.
• Too high torque means too thick fiber covering, so the speed of the feed roller 1 must be slowed down, while too low torque requires an increase in the speed of the feed roller 1, both until the difference AU from the measurement voltage and the setpoint value disappears.
• the setpoint value supplied to the controller 20 can be, for example, a voltage Ud fixed at a setpoint value resistor 18; this reaches the first summing point 17 via a terminal 24 of a switch 19.
• the card equipped with the device delivers a strip with a constant cross section only as long as the proportionality factors between the torque of the licker-in 4 and the number of the strip 26 do not change .
• a variable proportionality factor is, for example, the material-dependent ratio between the material supply and the tearing power of the licker-in 4, or the adjustable ratio of licker-in speed and delivery speed.
• the switch 19 is also used
• Terminal 23 connected.
• a setpoint value U S derived from the number of band 26 is applied to this terminal.
• a signal U B corresponding to the band number is generated in a band measuring element 14 and is led to a second summing point 21, where it is compared with a setpoint value U S for the band number. Date the resulting difference signal happens.
• the two configurations described here describe the basic principles of the setpoint specification for the controller 20. It may be sensible to combine several fixed and / or variable setpoint specifications, for example by additive superimposition, in order to compensate for example the idling torque of the licker-in 4 or the behavior of the To optimize regulation in different operating conditions (e.g. when starting the card).
• the card which is equipped with the device in the configuration described, is preferably driven by the four individual drives 3, 5, 10, 15.
• the An Drives 5 and 10 must be synchronized with each other for the card to work properly.
• the take-off side of the card (motor 15) is usual. also synchronized with motors 5 and 10; however, it can also usually be shut down separately or operated at slow speed. In order to protect the card from overfeeding in such an operating state, additional apparatus are required. To take precautions. For example, it is conceivable that the customer speed is measured continuously and in such an extraordinary operating state (e.g. also carding and stopping the card) either the target torque for the controller 20 is reduced in accordance with the customer speed, or the speed of motor 3 is synchronized with motor 15 . This is shown in FIG. 2, where a tachometer generator 27 is coupled to a rotating part that defines the strip take-off speed, for example the calender roller 13. In these cases, the signal UT corresponding to the tachometer speed is specified as the setpoint.
• FIG. 3 shows, as a further variant, the evaluation of the torque or the power of the tambour drive by determining the current consumption of the motor 10 by means of the measuring resistor 6 and using it for comparison with the target value.
• the covers 9 exert a torque on the rotating drum 8, which increases with the thickness of the window covering 7 on the drum.
• the device used in this way therefore acts primarily as a density controller for the fiber covering on the reel 8. In the end, however, this also regulates the band number
• the torque measurement of a rotating part of the card, the card or the like can also be carried out in another way than by measuring the power consumption.
• the drive shaft for the licker-in 4, or for the reel 8, as a torsion bar 29 by measuring its rotation and converting it into a corresponding signal.
• the drives for licker-in 4, drum 8 and pickup 11 can be carried out from a common motor 30, as is indicated in FIG. 4.
• a further possibility for measuring the torques for the driven drums of the card is to arrange a variable coupling 31 between the motor 30 and the shaft in question.
• the size of the slip between the drive and the driven axle, or the excitation of the variable clutch 31 necessary for a slip-free transmission is to be measured as a control signal and the difference is to be formed therefrom with a corresponding setpoint, as has already been described.

Landscapes

• Engineering & Computer Science (AREA)
• Textile Engineering (AREA)
• Preliminary Treatment Of Fibers (AREA)
• Oscillators With Electromechanical Resonators (AREA)
• Diaphragms For Electromechanical Transducers (AREA)
• Golf Clubs (AREA)
• Tires In General (AREA)
• Moulding By Coating Moulds (AREA)

Priority Applications (1)

Applications Claiming Priority (2)

Publications (1)

Family

ID=4185968

Family Applications (1)

Country Status (10)

Cited By (3)

Families Citing this family (23)

Citations (4)

Family Cites Families (5)

• 1980
  • 1980-01-17 CH CH39280A patent/CH640890A5/de not_active IP Right Cessation
  • 1980-09-30 US US06/293,221 patent/US4438548A/en not_active Expired - Lifetime
  • 1980-09-30 WO PCT/CH1980/000117 patent/WO1981002029A1/de not_active Ceased
  • 1980-09-30 DE DE8080901792T patent/DE3066099D1/de not_active Expired
  • 1980-09-30 EP EP80901792A patent/EP0043815B1/de not_active Expired
  • 1980-09-30 JP JP50216680A patent/JPS56501887A/ja active Pending
  • 1980-09-30 AT AT80901792T patent/ATE5826T1/de not_active IP Right Cessation
  • 1980-11-19 IT IT50197/80A patent/IT1128628B/it active
• 1981
  • 1981-01-16 ES ES498579A patent/ES8203996A1/es not_active Expired
  • 1981-09-16 SU SU813338398A patent/SU1165240A3/ru active
• 1984
  • 1984-06-01 JP JP1984080522U patent/JPS6016769U/ja active Pending

Patent Citations (4)

Also Published As

Similar Documents

Legal Events