Title of Invention

A COMBING MACHINE

Abstract

(57) Abstract: The present invention relates to a coming machine with several combing for supplying a singel head silver (2) each made from combed fibre material, with means (4) for joining the singel head slivers (2) into a sliver bunch (5), with a drafting arrangement (6) for drafting the sliver bunch, with means (11) for forming a combing machine sliver (12) from the drafted sliver bunch, with a sesor device (13, 13a) for continuous determination of the thickness of the combing machine sliver(12) or the mass of the sliver bunch (5) and with a comperator device of a processor (14) for compariing at least one prepared output singnal of the sensor device with a predetermoinable set value stored in the processor (14), as wherein the comparator device is part of at least one controller connected with the processor (14) for producing at least one actuating signal (16) for at least one element (27; 32; 35; 36; 4; 6; 10) of the combing heads, of the said measns (3, 4) for joining or of the drafting arrangement (6, 10) of the combing machine. PRICE: THIRTY RUPEES

Full Text

The invention relates to a combing machine. Such combing machines are known. The combing heads ±n them usually contain a nipper unit which is supplied with a lap to be combed and is reciprocated between a rear end position and a forward end position. In the rear end position the nipper unit is closed and holds a front end section of the lap towards a rotating circular comb. Thereafter the nipper unit is moved to the forward end position and opened, the forward end of the fibre tuft which is combed out by the circular comb is placed on the rear end section of the previously formed combing machine fleece which has been fed back by reverse rotation of detaching rollers. Thereafter the detaching rollers are rotated in the forward direction , so that they detach the fibre tuft from the lap disposed in the nipper unit and join it with the combing machine fleece. This process is called soldering. The fleeces formed in the combing heads are moulded into single head slivers by separate funnels which run on to a delivery table. The single head slivers are deflected on the delivery table and then run mutually parallel, as sliver bunch, into a drafting arrangement. A sensor device for continued determination of the thickness of the combing machine sliver or the mass of the sliver bunch is usually arranged after the drafting arrangement (or possibly even before the drafting arrangement). Such devices are known, for example, from the document EP-A-0 376 002. Known sensor devices for this purpose determine the thickness of the combing machine sliver in short intervals and calculate from the determined discrete thickness values a mean value signal and a fluctuation signal. The short intervals correspond, for example, to' a sliver run path (after the drafting arrangement) in the magnitude of 1 centimetre or a time interval of some milliseconds. The mean value signal represents the thickness value of the sliver averaged over a longer interval. The fluctuation signal represents the variation of the determined discrete thickness values, for example, which were calculated for a longer interval. A spectrum of the sliver thickness fluctuations can be also calculated from the discrete thickness values. The longer interval may correspond to a sliver run path in the magnitude of 100 metres or a time interval in the magnitude of 1 minute. A comparator device can then compare the mean value signal and/or the fluctuation signal with one set value each. In known combing machines pursuant to the preamble of claim 1 an output signal of the comparator device may be used to turn off the combing machine when the mean value signal or the fluctuation signal deviates by more than a predetermined tolerance from the respective set value. The invention has the object of arranging the combing machine pursuant to the preamble of claim 1 in such a way that the thickness of the combing machine sliver remains as constant as possible over time. The combing machine in accordance with the invention with which this object is achieved is characterized in that the comparator device is part of at least one controller for producing at least one actuating signal for at least one element of the combing heads, of the said means for joining or of the drafting arrangement of the combing machine. Various elements in the combing machine can be influenced with such actuating signals which are issued by such a controller or by such controllers in order to achieve automatically an evening of the thickness of the produced combing machine sliver during operation. For example, such elements can be: A drive device (e.g. drive motor) for nipper units in the combing heads (e.g. change of the detaching distance, i.e. the forward end position of the nipper units), drive devices for feed cylinders held in the nipper units (change of feed length), a drive device for detaching rollers in the combing heads (change of detaching time and/or the detaching length and/or the detaching speed and/or the soldering distance), adjusting devices for top combs in the combing heads (change of pin penetration depth), drive devices and/or adjusting devices for the drafting arrangement (change of the size of draft and/or the distances or the load of the drafting arrangement cylinders) and finally also adjusting devices for deflection pulleys for the single head slivers on a delivery table (change of the path lengths for the single head slivers). To influence the combing process it is also possible to vary the low pressure of the suction for the comber waste by adjusting the blower unit used for this purpose. An important cause for short-term fluctuations in the thickness of the combing machine sliver (fluctuations with a wavelength of some centimetres up to some metres in the drafted combing machine sliver) is contained in detaching and soldering processes. Such short-term fluctuations can be reduced favourably to a minimum by influencing the drive device for the detaching cylinders. Long-term changes of the thickness of the combing machine sliver can be compensated, for example, by influencing the drive device for the drafting arrangement (change of the size of the draft) . Preferred embodiments of the invention are defamed in the dependent claims. Accordingly, the present invention provides a combing machine with several combing heads for supplying a single head sliver each made from combed fibre material, with means for joining the single head slivers into a sliver bunch, with a drafting arrangement for drafting the sliver bunch, with means for forming a combing machine sliver from the drafted sliver bunch, with a sensor device for continuous determination of the thickness of the combing machine sliver or the mass of the sliver bunch and with a comparator device of a processor for comparing at least one prepared ou^ut signal of the sensor device with a predeterminable set value stored in the processor, as wherein the comparator device is part of at least one controller connected with the processor for producing at least one actuating signal for at least one element of the combing heads, of the said means for joining or of the drafting arrangement of the combing machine. Embodiments of the invention are explained in closer detail with reference to the accompanying drawings, wherein: Fig. 1 shows a schematic top view of parts of a combing machine; Fig. 2 shows a schematic front view of Fig. 1; Fig. 3 shows a schematic vertical section through parts of one of the combing heads of the machine; Fig. 4 is a graphical representation of the thickness of the formed combing machine sliver as determined by a sensor device of the machine; Fig. 5 shows a spectrum of the fluctuations in the thickness of the combing machine sliver as shown in Fig. 4 and Fig. 6 shows a graphical representation of a reciprocating rotating movement of detaching rollers in the combing machine. The combing machine as shown in Figs. 1 and 2 comprises a row of eight combing heads, for example, which each carry a lap roll 1 and supply a single head sliver 2 from combed fibre material. The single head slivers 2 travel on to a delivery table 3 and are deflected thereon by a deflection roll 4 each, so that they travel towards a drafting arrangement 6 mutually parallel forming a sliver bunch 5. Three pairs of rollers 7, 8 and 9 of the drafting arrangement are shown schematically. They are rotated continuously by a drive device 10. exit of the drafting arrangement 6 which forms the drafted sliver or fleece into an approximately round sliver 12. This round combing machine sliver 12 passes through a sensor device 13 in form of a measuring funnel which continuously emits an electric signal representative of the thickness of the combing machine sliver. This signal is supplied to a processor 14. The signal representing the thickness of the sliver 12 is prepared at first in the processor 14. A mean value signal is formed which is representative of the average value of the sliver thickness. A second signal is calculated as a percentage deviation of the momentary sliver thickness from the average value. This second signal, i.e. the deviation of the momentary sliver thickness from a mean value do/ is shown graphically in Fig. 4 for approx. 20 m length L of sliver 12. Moreover, the momentary sliver thickness dj_ is determined in short intervals, e.g. in intervals of some milliseconds (1 to 10 milliseconds or 3 to 6 milliseconds) or in intervals of approx. 1 cm (0.5 cm to 2 cm) along the drafted sliver, and there from a variation coefficient is calculated. The number of samples can be approx. within the magnitude of 10^, according to an interval of 10 to 100 seconds or a distance in the magnitude of 100 m along sliver 12, for example. Moreover, it is possible to determine a spectrum of fluctuations of the sliver thickness. Such a spectrum, i.e. the graphic' representation of the amplitude of the fluctuations in successive zones of the fluctuation wavelength X, is shown in Fig. 5. Processor 14 further contains at least one controller. A comparator device forms a part of the controller or of each of the controllers. The comparator device can compare the signals described above, i.e. the mean value dQ of the sliver thickness and/or the variation coefficient CV and/or the spectrum of the sliver thickness fluctuations (or a part of this spectrum), with predeterminable set values which are supplied via lines 15. Such a set value can be a predeterminable threshold value for the size of an amplitude, for example, as is shown in the example of Fig. 5. This means that the soldering process must be influenced accordingly so that the soldering position does not produce an amplitude exceeding the threshold value. Depending on the result(s) of the comparison, each controller generates on lines 16 an actuating signal for one element each of the combing heads or for an adjusting device for adjusting the deflection rollers 4 on the delivery table 3 or for the drafting arrangement 6 and/or for its drive device 10. A further sensor 13a (shown with the broken line) may be arranged in front of drafting arrangement 6 in addition to the sensor device 13, which sensor 13a measures the fibre mass supplied to drafting arrangement 6 and also sends the signal to processor 14. Processor 14 then carries out a comparison with a set value. The value resulting from this comparison (deviation from set value) is prepared as control signal in order to intervene in a regulating manner in the drive system of drafting arrangement 6. In this way it is particularly possible to compensate short-term' fluctuations in the supplied fibre quantity by regulating the drafting arrangement if it is provided with a control device. It is possible to detect a sliver breakage in particular with the sensor 13a and thus initiate respective measures. It is also possible to combine both signals of sensors 13 and 13a with each other in order to form there from a control signal for the control intervention. Such measuring and control systems are well-known from practice and from patent literature (e.g. from EP-A 1 412 488), which shall therefore not be discussed herein in closer detail. Elements of the combing heads are shown in Fig. 3, which shows a schematic vertical section through one of the combing heads. The frame of the combing machine holds a nipper shaft 20, a circular comb shaft 21, lap rollers 22 carrying lap roll 1, detaching cylinders 23 and draw-off rollers 24. The nipper shaft 20 carries the nipper arms 25 on which the rear end of a lower nipper frame 2 6 is articulated. During the operation the nipper shaft is pivoted back and forth by a drive device 27, e.g. a gear, which is only shown schematically herein in form of a block, in order to move the lower nipper frame 26 between a rear end position and the represented forward end position. In the rear end position of the lower nipper frame 26 the nipper unit, which also includes a top nipper knife 29 carried by top nipper arms 28, is closed, a forward end section of the lap 3 0 which is wound off from the lap roll 1 is tightly clamped between the top nipper knife 2 9 and a lower nipper plate and is combed out by a circular comb segment 31. The circular comb segment 31 is seated on the circular comb shaft 21 which is continuously rotated by a drive device 32. The nipper unit 26, 28, 2 9 is then moved to the illustrated forward end position and opened and the forward end of' the fibre tuft which is combed out by the circular comb segment 31 is placed on the rear end section of the previously formed combing machine fleece 33 which has been fed back by reverse rotation of the detaching cylinders 23. The detaching cylinders 23 are rotated back and forth with a pilgrim-step movement by a drive device 34, preferably a servomotor, as is shown graphically in Fig. 6. Fig. 6 shows the path of a point on the circumference of one of the detaching cylinders 23 during a rotation of the round comb shaft 21. At rotational angle 0 of the circular comb shaft the lower nipper frame 26 is in its rear end position (not shown). Up to the rotational angle of 90° the detaching cylinders 23 only rotate very little. Approximately at A the detaching process begins with the reverse rotation of the detaching cylinders 23. After the reverse rotation the nipper unit - as was already mentioned - reaches its forward end position and places the forward end of the combed fibre tuft on the rear end section of fleece 33 which was fed back. The detaching cylinders 23 are now rotated in the forward direction so that they grasp the fibre tuft, detach it from the lap 30 disposed in the nipper unit 26, 28, 29, pull it through a top comb 35 arranged on the lower nipper frame 26 and join it with the fleece 33. This process is known as soldering. In Fig. 6 a tangent t is shown at the segment of the movement curve representing the forward rotation; the steepness of this tangent t corresponds to the detaching speed. The double arrow a shows the detaching length and a double arrow 1 represents the soldering distance, i.e. the distance between successive soldering. The mentioned values, i.e. the position of beginning A of the detaching process, the detaching speed (t), the' detaching length a and the soldering distance 1, can all have an influence on the mean value and/or on the fluctuations of the thickness of the combing machine sliver 12. From the spectrum in Fig. 5 it can be seen that fluctuations with a wavelength A, of approx. 50 cm can have a relatively large amplitude. This wavelength of approx. 50 cm corresponds to a soldering distance 1 of approx. 31 mm when the draft in the drafting arrangement 6 is approx. sixteen. The relatively strong fluctuations thus arise as a consequence of the soldering and the amplitude of these fluctuations can be reduced by a controlled change of one or several of the said values. Therefore the controller or at least one of the controllers in processor 14 (Fig. 2) emits an actuating signal for the drive device 34 of the detaching cylinders 23 in preferred embodiments of the invention. If the drive device 34 is a mechanical gear the actuating signal may actuate an adjusting device for an element of the gear in order to change the position of beginning A (Fig. 6) of the detaching process. The drive device 34, however, is preferably a servomotor and the actuating signal can then control a feed device for the servomotor in order to change the position of the beginning A of the detaching process or the detaching speed (t) or the detaching length a or the soldering distance 1. The fleece 33 leaving the detaching cylinders 23 is then further conveyed by the draw-off rollers 24. A funnel forms each of the fleeces 33 into a single head sliver 2 which then travels on to the delivery table 3. The single head slivers 2 are deflected on the delivery table 3 by the deflection rollers 4 and joined into a sliver bunch 5. The irregularities of the single head slivers in the sliver bunch 5 caused by the solderings' are not all situated at the same location, but are displaced with respect to one another in the longitudinal direction. The displacements depend on the different path lengths on the delivery table 3. The path length for each single head sliver 2 can be changed by adjusting the allocated deflection roller 4 in order to achieve in the sliver bunch 5 (and thus also in the drafted sliver 12 after the drafting arrangement 6) a mutual compensation of the single head irregularities. The controller or at least one of the controllers in the processor 14 can issue an actuating signal which actuates the adjusting devices (not shown) for adjusting some or all of the deflection rollers 4. Long-term changes in the thickness of the combing machine sliver 12 (which are represented by the mean value signal formed in processor 14) can be compensated in the easiest way by respective changes in the size of the draft caused in the drafting arrangement 6. In preferred embodiments of the inventions the controller or at least one of the controllers in the processor 14 issues an actuating signal for the drive device 10 of the drafting arrangement 6. With this actuating signal the rotational speed of the front pair of rollers 9, and possibly also the speed of the central pair of rollers 8 in the drafting arrangement 6, can be controlled in such a way that the mean thickness of the drafted combing machine sliver 12 corresponds in a near constant manner to the predetermined set value. The actuating signal can control a feed device, for example, which feeds a servomotor driving the drafting arrangement rollers. As was already described above, short-term fluctuations can also be determined by attaching a further sensor 13a at the entrance of the drafting arrangement 6 and be transferred to processor 14 for controlling the drafting arrangement drive. It is also possible to form a combined signal from the signals of sensors 13 and 13a which can be used as a basis for intervening in the actuating elements for other elements (e.g. the separate drive of the detaching rollers) of the combing heads. An actuating signal which is issued by the controller or one of the controllers contained in processor 14 can also control other elements -of the combing machine in order to keep changes and/or fluctuations in the thickness of the combing machine sliver 12 which are determined by the sensor device 13 to a minimum. Thus, for example, the drive device 27 can be controlled by the nipper shaft 2 0 in order to change the forward end position of the lower nipper frame 26 and thus the detaching distance. (The detaching distance is in the forward end position of the nipper unit the distance from the nip line on the lower nipper plate to the nip line on the adjacent (rear) detaching cylinder 23.) A power supply for a drive servomotor of a feed cylinder 36 held in the lower nipper frame 26 can be controlled in order to change the feed value. The feed value is the path by which the intermittently rotated feed cylinder 3 6 advances the incoming lap 3 0 during each reciprocating movement of the nipper unit 26, 28, 29. An adjusting device for the top comb 3 5 held in each combing head on the lower nipper frame 26 can be actuated with an actuating signal in order to change the pin penetration depth of the top comb in the fibre tuft which is detached by the detaching cylinder 23. An adjusting device for the axes of the drafting arrangement rollers 7, 8, 9 can be actuated with an actuating signal in order to change the distances between these axes. The combing process can also be influenced by the adjustment of the blower unit which produces the low pressure for the suction and is used for discharging the comber waste and other impurities. Moreover, the soldering process can be influenced in this way. WE CLAIM; 1. A combing machine with several combing heads for supplying a single head sliver (2) each made from combed fibre material, with means (4) for joining the single head slivers (2) into a sliver bunch (5), with a drafting arrangement (6) for drafting the sliver bunch, with means (11) for forming a combing machine sliver (12) from the drafted sliver bunch, with a sensor device (13, 13a) for continuous determination of the thickness of the combing machine sliver (12) or the mass of the sliver bunch (5) and with a comparator device of a processor (14) for comparing at least one prepared output signal of the sensor device with a predeterminable set value stored in the processor (14), wherein the comparator device is part of at least one confroller connected with the processor (14) for producing at least one actuating signal (16) for at least one element (27; 32; 35; 36; 4; 6; 10) of the combing heads, of the said means (3, 4) for joining or of the drafting arrangement (6,10) of the combing machine. 2. The combing machine as claimed in claim 1, wiierein the processor (14) is provided to prepare a fluctuation signal from the delivered signal of the sensor device (13), which fluctuation signal is representative of the variation of the thickness of the combing machine sliver (12) measured with the sensor device (13) in predeterminable intervals or of the measured mass of the sliver bunch (5) measured with the sensor device (13a) or a spectrum of the fluctuations of this thickness or this mass and wherein the comparator device of the processor (14) compares this fluctuation signal with a predeterminable set value, and which the comparator device is part of a controller which is connected with a drive device (34) for at least one detaching cylinder (23) in each of the combing heads. 3. The combing machine as claimed in claim 2, wherein at least one of the following values is adjustable with adjusting devices by actuating signal which is delivered by the controller to the drive device (34) of the detaching cylinder: beginning (A) of the detaching process, detaching length (a), detaching speed (t), soldering distance (1). 4. The combing machine as claimed in claim 2 or 3, wherein the drive device (34) for the detaching cylinder comprises a servomotor. 5. The combing machine as claimed in any one of the claims 1 to 4, wherein deflection rollers (4), adjustable with adjusting devices, are arranged on a delivery table (3) for deflecting towards the drafting arrangement (6) the single head slivers (2) issued by the combing heads and wherein a fluctuation signal is prepared by a processor (14) from the signal of the sensor device (13, 13a) which is representative of the variation of the thickness of the combing machine sliver (12) measured in predeterminable intervals or of the mass of the sliver bunch (5) or a spectrum of the fluctuations of this thickness and wherein the comparator device of the processor (14) compares this fluctuation signal with a predeterminable set value and wherein the comparator device is part of a controller which is connected with the adjusting devices for the deflection rollers (4). 6. The combing machine as claimed in any one of the claims 1 to 5, wherein the sensor device (13) is arranged behind a drafting arrangement (6) and a mean value signal is prepared by a processor (14) from the signal of the sensor device which is representative of the mean value of the thickness of the sliver after a passage of a predeterminable length of the combing machine sliver (12) drafted in the drafting arrangement (6) and wherein the comparator device of the processor (14) compares this mean value signal with a predeterminable set value, and wherein the comparator device is part of a controller which is connected with the drive device (10) for the drafting arrangement (6). 7. The combing machine as claimed in claim 6, wherein the size of the draft in the drafting arrangement (6) is adjustable in the drive device (10) which is connected with the controller. 8. A combing machine substantially as herein described with reference to the accompanying drawings.

Documents:

0119-mas-1996 abstract.jpg

0119-mas-1996 abstract.pdf

0119-mas-1996 claims.pdf

0119-mas-1996 correspondence-others.pdf

0119-mas-1996 correspondence-po.pdf

0119-mas-1996 description(complete).pdf

0119-mas-1996 drawings.pdf

0119-mas-1996 form-2.pdf

0119-mas-1996 form-26.pdf

0119-mas-1996 form-4.pdf

0119-mas-1996 petition.pdf