GB2462717A

GB2462717A - Sliver Thickness Sensor Associated with Roll Housing

Info

Publication number: GB2462717A
Application number: GB0914236A
Authority: GB
Inventors: Franz-Josef Minter; Johannes Bossmann
Original assignee: Truetzschler GmbH and Co KG
Current assignee: Truetzschler GmbH and Co KG
Priority date: 2008-08-19
Filing date: 2009-08-14
Publication date: 2010-02-24
Anticipated expiration: 2029-08-14
Also published as: CN101654819B; DE102008049363A1; CH699383B1; CH699383A2; IT1397165B1; BRPI0902714B1; JP5543145B2; GB0914236D0; DE102008049363B4; JP2010047891A; CN101654819A; BRPI0902714B8; GB2462717B; ITMI20091116A1; BRPI0902714A2

Abstract

A spinning room preparation machine has a pair of rolls 15a, 16a pressed against one another, one of which 15a rotates about an immovable axis and one of which 16a rotates about a movable axis, a non-contact spacing sensor 57 for measuring the spacing between the rolls being associated with the holding element 52, 53 of one of the holding elements, preferably the immovable roll 15a, the sensed or counterpart surface being associated with the other holding element. The holding element 52, 53 may be a rotary bearing which may be Aluminium (Al) and may be a spring loaded movable bearing. The sensor 57 may be an inductive proximity or displacement sensor, acoustic e.g. ultrasound sensor, a plunger coil and core, a laser sensor or an optical sensor using visible or infra-red (IR) light. The sensor may sense a surface of the other housing 53, or a counterpart element integrated in the other housing (figure 6). The machine may be a carding machine, draw frame, combing machine or flyer. The spacing sensor 57 may be separable from the housing. This allows simple replacement of parts and space to be saved.

Description

Apparatus for or at a spinning room preparation machine which has a drawing mechanism for drawing out strand-form fibre material The invention relates to an apparatus for or at a spinning room preparation machine which has a drawing mechanism for drawing out strand-form fibre material, especially a carding machine, draw frame, combing machine or flyer, for continuously registering the cross-section and/or mass of at least one fibre sliver.

In practice it is customary to measure fibre sliver thicknesses, especially for the purpose of levelling out irregularities in one or more fibre sliver(s) introduced into a spinning room preparation machine. Measurement of such a kind is also desirable at the exit from the machine for quality control of the drawn-out material. In addition to said quality control, measurement values relating to the density or thickness of the fibre sliver are also used for shutting down the machines if prespecified mass variation limits are exceeded and a high-quality product is therefore no longer obtained.

In a known apparatus having a drawing mechanism (WO 91/16595 A), a fibre sliver is guided between an immovable roll and a movable roll that can be pressed against it (draw-off roll and sensed roll) . The draw-off roll and the sensed roll are fixed on shafts. The draw-off roll is rotatably mounted, by means of its shaft, in a first bearing housing. The bearing housing is immovably arranged in the draw frame. The sensed roll is rotatably mounted, on its shaft, in a second bearing housing. The second bearing housing is so arranged in the draw frame that it can undergo excursion in a direction A. The excursion occurs against the force of a compression spring.

The compression spring presses the sensed roll against the draw-off roll and rests against an immovable component of the draw frame. A measurement plate is arranged on the second housing. This measurement plate ensures that there is an exact reference surface for a displacement sensor.

The displacement sensor registers a spacing B between the displacement sensor and the measurement plate. A change in the spacing B is conveyed by the displacement sensor to a sliver monitor by means of a change in an electrical voltage. The displacement sensor accordingly serves as a signal transducer. The spacing B used as the measured distance is usually very small, that is to say a few tenths of a millimetre. Even the smallest changes in the spacing between the draw-off roll and the sensed roll are registered by the displacement sensor. The displacement sensor is fixed to the immovable component of the draw frame, against which the compression spring rests. This component and also, as a result, the displacement sensor are arranged in an empty space on the side remote from the roll nip at a spacing from the second bearing housing. One disadvantage lies in the considerable space requirement where space is limited. In addition, the outlay in terms of arrangement, namely the outlay in terms of installation, for mounting of the displacement sensor is disadvantageous.

Finally, the arrangement on the immovable component requires a specific adjustment or setting procedure for the displacement sensor.

It is an aim of the invention to provide an apparatus of the kind described at the beginning that avoids or mitigates the mentioned disadvantages and especially that allows arrangement of the spacing sensor by simple means, in particular where space is limited, and that allows improved association of the spacinq sensor with the sensed surface.

The invention provides an apparatus for or at a spinning room preparation machine which has a drawing mechanism for drawing out strand-form fibre material, for continuously registering the cross-section and/or mass of at least one fibre sliver, having: a pair of measuring rolls arranged to be pressed against one another, a first said roll being immovably arranged and a second said roll being arranged to be movable away therefrom; a first holding element holding said first roll; a second holding element holding said second roll; and a non-contact-making spacing sensor for measuring the spacing from a counterpart surface; wherein the sensor is associated with one of said first and second holding elements and the counterpart surface is associated with the other of said first and second holding elements, and the spacing sensor and the counterpart surface are arranged on those sides of the holding elements which face one another.

A space-saving arrangement is produced by associating the spacing sensor with the holding element for the roll other than that roll with which the counterpart surface (i.e. sensed surface) is associated and arranging the sensed surface opposite the spacing sensor so positioned.

Associating the spacing sensor with the existing holding element for the other roll advantageously allows, at the same time, a simplification in terms of construction and installation. The changing spacing between the holding elements is advantageously employed for measuring fibre sliver thicknesses.

In a preferred embodiment the spacing sensor is mechanically integrated into the holding element, simplifying the spacing sensor adjustment procedure in especially elegant manner. The arrangement of the invention -which is simple in terms of construction -of the spacing sensor and the sensed surface is space-saving. The spacing sensor and the sensed surface are accordingly in each case combined with a holding element of the spinning room preparation machine so that this combination serves several functions at the same time.

In one especially advantageous embodiment, the spacing sensor is integrated into the holding element for said roll.

Advantageously, the spacing sensor is constructed as a separate part of the holding element. Advantageously, the holding element is constructed as one piece with at least one part of the spacing sensor. Preferably, the spacing sensor space is recessed into a space formed at least in part by a depression (recess) in the holding element.

Advantageously, the holding element is a bearing element for the roll. In the case of the immovable roll, the bearing element may advantageously be an immovable rotary bearing. In the case of the movable roll the bearing element may advantageously be a movable rotary bearing.

Preferably, the movable bearing element is spring-loaded.

The bearing element may be made of, for example, aluminium.

In one embodiment, the spacing sensor is immovable and the counterpart surface is arranged to move relative to the spacing sensor. Advantageously, the spacing sensor is arranged to move and the counterpart surface is immovable relative to the spacing sensor. Advantageously, the counterpart surface is an external surface of the holding element for the other roll. Preferably, the counterpart surface is a surface of a counterpart element which is associated with the other roll. Advantageously, the counterpart element is integrated into the holding element for the other roll. Advantageously, the sensed surface is flat. Advantageously, the sensed surface is smooth.

Advantageously, the spacing sensor is a distance-measuring sensor using waves or beams.

The spacing sensor may, for example, be capable of registering the change in an induction. For example, the spacing measurement device may be an inductive proximity initiator. Preferably, the spacing sensor is an inductive displacement sensor. For example, the inductive displacement sensor may comprise a plunger coil and a plunger core. In another embodiment, an optical spacing sensor (distance-measuring sensor) may be employed, for example, a light sensor, such as a laser sensor, a sensor that uses visible light, or a sensor that uses infra-red light.

In yet a further embodiment, an acoustic spacing sensor (distance-measuring sensor) may be employed, for example, an ultrasound spacing sensor (distance-measuring sensor) Advantageously, the spacing sensor and the counterpart element are arranged in an enclosed housing.

In a preferred embodiment, the apparatus comprises an evaluation device which is in communication with an electronic control and regulation device. That enables settings of the machine to be adjusted in dependence on the measurements made. Advantageously, the spacing sensor is a sensor that operates in analogue manner.

The apparatus may be employed for registering and/or displaying a sliver break.

Advantageously, the spacing sensor indirectly senses the excursions of the sensed roll. Advantageously, the spacing sensor is employed for registering the sliver mass of an elongate, substantially untwisted fibre sliver combination.

Advantageously, the fibre sliver combination substantially consists of natural fibres, especially cotton, and/or synthetic fibre materials. Advantageously, the spacing sensor is used for measuring the sliver mass in the case of a continuously moving fibre sliver combination.

Advantageously, the registered values for the sliver mass are used for levelling out sliver mass variations in the fibre sliver combination by controlling at least one drafting element of a spinning room preparation machine in which the fibre sliver combination is being drawn out.

Advantageously, the spinning room preparation machine is an autolevelling carding machine, a carding machine having an autolevelling drawing mechanism, a combing machine having an autolevelling drawing mechanism, or a draw frame.

Advantageously, registration of the sliver mass of a moving fibre sliver combination is provided at a spinning room preparation machine having a plurality of successive drafting elements for drawing out the fibre sliver.

The spacing sensor may be arranged for example at the intake of and/or exit from a drawing mechanism of the spinning room preparation machine. Advantageously, the sliver mass variations are monitored at the intake and/or exit and, where necessary, the spinning room preparation machine is switched off and/or a warning signal is emitted if values for sliver mass and/or sliver mass variations are above or below threshold values.

Advantageously, the spacing sensor is arranged to register sliver breaks of the fibre sliver combination or of a fibre sliver of the fibre sliver combination.

Advantageously, on the basis of the calculated values for sliver mass, a levelling unit of the spinning room preparation machine controls at least one of the drafting elements for levelling out the sliver mass variations (intake levelling) . Advantageously, on the basis of the calculated values for sliver mass, a levelling unit of the spinning room preparation machine controls at least one of the drafting e]ements for]evellinq out the sliver mass variations (exit levelling) . In one embodiment, the intake levelling and exit levelling form an interlinked control (simultaneous open-loop and closed-loop control) Advantageously, the measuring frequency with which the resonant frequency modifications are performed is matched to the intake speed of the fibre sliver combination entering the spinning room preparation machine or to the delivery speed of the fibre sliver combination leaving the spinning room preparation machine. In one embodiment, the measuring frequency is matched to a defined, preferably constant, sensing length (length-based sensing) . In another embodiment, the measuring frequency is matched to a defined time period (time-based sensing) which is dependent on the speed of the fibre sliver combination.

Advantageously, the sensing which registers, on each measurement, a particular portion of the fibre sliver combination is carried out in a plurality of measurements along the fibre sliver combination that are displaced with respect to one another and that overlap one another.

Advantageously, a spectrogram or a part of a spectrogram of the fibre sliver combination is produced or supplemented using the measurement values obtained by means of the at least one spacing sensor. Advantageously, a spectrogram of the fibre sliver combination is recorded at the intake of and/or at the exit from the spinning room preparation machine. In one embodiment, a plurality of fibre slivers running next to one another and, in plan view, substantially in parallel are guided through the spinning room preparation machine from the intake to the exit.

Advantageously, the fibre sliver combination or individual groups of fibre slivers forming the fibre sliver combination are guided through at least one funnel or through guiding elements, for example guiding plates or guiding bars. Where present, the guiding element may be a sliver guide or a web guide. Advantageously, the biasing of the movably mounted holding element for the spacing sensor is accomplished, and can be adjusted, by mechanical, electrical, hydraulic or pneumatic means, for example springs, weights, intrinsic resilience, loading cylinders, magnets or the like. In one embodiment, the axes of the draw-off rolls at the exit are horizontally arranged. In another embodiment, the axes of the draw-off rolls at the exit are vertically arranged. Advantageously, the arrangement is such that control pulses are sent to a controller. Preferably, the controller adjusts the speed of rotation of at least one drive motor of the drafting draw frame.

The invention further provides a spinning room preparation machine, especially a carding machine, draw frame or combing machine, having at least one spacing sensor arranged according to the invention for measuring the sliver mass of a continuously moving fibre sliver combination. Advantageously, the at least one spacing sensor is arranged at the intake of the spinning room preparation machine. As well or instead, there may be at least one spacing sensor arranged at the exit from the spinning room preparation machine. Advantageously, the at least one spacing sensor is connected to a levelling unit, which subjects at least one drafting element of the spinning room preparation machine to open-loop and/or closed-loop control on the basis of the measurement values of the sliver mass of the fibre sliver combination.

Advantageously, a plurality of fibre slivers running next to one another and in parallel through the at least one spacing sensor can be registered. Advantageously, a plurality of fibre slivers running next to one another and, in plan view, substantially in parallel are arranged to be quided through the spinning room preparation machine from the intake to the exit. Advantageously, the spacing, from the spacing sensor, of the roll pair associated with the spacing sensor is small. Advantageously, the spacing sensor is an inductive analogue sensor. In one preferred embodiment, the two rolls, simultaneously in the form of draw-off rolls, are arranged immediately downstream of the funnel-shaped sliver guide, web guide or the like.

Advantageously, the holding element is a housing for a rotary bearing of a roll. Advantageously, at least one roll is driven. Advantageously, the spacing measurement device is a distance-measuring sensor. Advantageously, the spacing measurement device is in communication with an electrical evaluation device. Advantageously, the spacing measurement device registers the spacings from a counterpart element located opposite the sensor surface.

The invention also provides an apparatus for or at a spinning room preparation machine which has a drawing mechanism for drawing out strand-form fibre material, especially a carding machine, draw frame, combing machine or flyer, for continuously registering the cross-section and/or mass of at least one fibre sliver, having a pair of measuring rolls arranged to be pressed against one another, one of the rolls being immovably arranged and the other being arranged to be movable away therefrom, and having a non-contact-making spacing sensor for measuring the spacing from a counterpart surface (sensed surface) which is associated with the holding element for the one roll, wherein the spacing sensor is associated with the holding element for the other roll, and the spacing sensor and the counterpart surface are arranged on those sides of the holding elements which face one another.

Certain illustrative embodiment of the invention are described hereinafter in greater detail with reference to the accompanying drawings, in which: -10 -Fig. 1 is a diagrammatic side view of an autoleveller draw frame with an apparatus according to the invention; Fig. 2 is a diagrammatic side view of a carding machine drawing mechanism with an apparatus according to the invention; Figs. 3a, 3b are side views of an apparatus according to a first embodiment of the invention with an immovable bearing housing and a bearing housing that is movable in rotation, each having rotary bearings and shaft ends of two draw-off rolls, in the operating position (Fig. 3a) and in the fully opened position (Fig. 3b) ; Figs. 4a, 4b show, in perspective, an embodiment having an integrated spacing sensor arranged in a recess of an immovable housing for a draw-off roll, in a side view (Fig. 4a) and in a top view (Fig. 4b); Fig. 5 shows part of an embodiment having a housing for an immovable roll with a rotary bearing and draw-off roll, a spacing sensor being arranged in a groove in the immovably mounted housing; Fig. 6 shows, in diagrammatic form, an embodiment having an integrated inductive analogue spacing sensor with a sensor surface and with a counterpart surface located opposite it at a spacing; and Fig. 7 shows an embodiment having a spacing sensor in the form of a light sensor having a transmitter and receiver.

-11 -With reference to Figure 1, a draw frame 1, for example a ID 03 draw frame made by Trdtzschler GmbH & Co. KG of Monchengladbach, Germany, has a drawing mechanism 2, upstream of which is an intake 3 of the drawing mechanism and downstream of which is an exit 4 from the drawing mechanism. The fibre slivers 5, coming from cans (not shown), enter the sliver guide 6 and, drawn by the draw-off rolls 7, 8, are transported past the measuring element (spacing sensor 9) . The drawing mechanism 2 is designed as a 4-over-3 drawing mechanism, that is to say it consists of three lower rolls I, II, III (I delivery lower roll, II middle lower roll, III intake lower roll) and four upper rolls 11, 12, 13, 14. Drafting of the fibre sliver combination 5 from a plurality of fibre slivers 5 is carried out in the drawing mechanism 2. Drafting is composed of preliminary drafting and main drafting. The roll pairs 14/111 and 13/11 form the preliminary draft zone and the roll pairs 13/11 and 11, 12/I form the main draft zone. The fibre sliver combination 5' is drawn out in the preliminary draft zone and the fibre sliver combination 5'' is drawn out in the main draft zone. The drawn-out fibre slivers 5' reach a web guide 10 in the exit 4 from the drawing mechanism and, by means of the draw-off rolls 15, 16, are drawn through a sliver funnel 17, in which they are combined to form one fibre sliver 18, which is then deposited in cans. Reference letter A denotes the work direction.

The draw-off rolls 7, 8, the intake lower roll III and the middle lower roll II, which are connected to one another mechanically, for example by toothed belts, are driven by the control motor 19, it being possible, in the process, for a desired value to be specified. (The associated upper rolls 14 and 13, respectively, revolve by virtue of the motion of the lower rolls.) The delivery -12 -lower roll I and the draw-off rolls 15, 16 are driven by the main motor 20. The control motor 19 and the main motor 20 each have their own controller 21 and 22, respectively. Control (speed-of-rotation control) is carried out in each case by means of a closed control loop, a tachogenerator 23 being associated with the control motor 19 and a tachogenerator 24 being associated with the main motor 20. At the intake 3 of the drawing mechanism, a variable proportional to the mass of the fibre slivers 5 fed in, for example their cross-section, is measured by an intake measuring element. At the exit 4 from the drawing mechanism, the cross-section (thickness) of the delivered fibre sliver 18 is ascertained by an exit measuring element (spacing sensor 25) associated with the draw-off rolls 15, 16. A central computer unit 26 (control and regulation device), for example a microcomputer with a microprocessor, sends a setting for the desired value for the control motor 19 to the controller 21. The measurement values of the two measuring elements 9 and 25 are sent to the central computer unit 26 during the drawing process. The desired value for the control motor 19 is determined in the central computer unit 26 from the measurement values of the intake measuring element 9 and from the desired value for the cross-section of the delivered fibre sliver 18. The measurement values of the exit measuring element 25 are used for monitoring the delivered fibre sliver 18 (delivered sliver monitoring) and for on-line determination of optimum preliminary drafting. By means of this control system, it is possible for variations in the cross-section of the fibre slivers 5 fed in to be compensated, and for the fibre sliver to be made more uniform, by appropriately regulating the drafting process. Reference numeral 27 denotes a display monitor, 28 an interface, 29 an input device and 30 a pressure bar. The measurement values from -13 -the measuring element 25, for example variations in the thickness of the fibre sliver 18, are sent to a memory 31 in the computer 26.

In each case, the draw-off rolls 7, 8 at the intake of the draw frame and the draw-off rolls 15, 16 at the exit have a double function; they serve for drawing off the respective fibre sliver combination and 18 and, at the same time, sense the respective fibre sliver combination 51V and 18.

The cross-section and/or mass of the fibre sliver 18 passing through the roll nip between the draw-off rolls 15, 16 is/are registered, for example, using the apparatus shown in Figures 3a, 3b.

The apparatus shown in Figures 3a, 3b can likewise be employed for registering the cross-section and/or mass of the fibre sliver combination 5 (consisting of a plurality of fibre slivers) passing through the roll nip between the draw-off rolls 7, 8.

Fig. 2 shows an arrangement in which, between a carding machine, for example a TC 07 carding machine made by Trdtzschler GmbH & Co. KG, and the coiling plate 35, a carding machine drawing mechanism 36 is arranged above the coiling plate 35. The carding machine drawing mechanism 36 is designed as a 3-over-3 drawing mechanism, that is to say it consists of three lower rolls I, II, III and three upper rolls 37, 38, 39. At the intake of the drawing mechanism 36 there is arranged an intake funnel 40 and at the exit from the drawing mechanism there is arranged an exit funnel 41.

Downstream of the exit funnel 41 are two draw-off rolls 42, 43, which rotate in the direction of the curved arrows and draw off the drawn-out fibre sliver 44 from the exit funnel 41. The delivery lower roll I, the draw-off rolls 42, 43 and the coiling plate 35 are driven by a main motor 45, and the intake and middle lower rolls, respectively III and II, -14 -are driven by a control motor 46. The motors 45 and 46 are connected to an electronic control and regulation device (not shown) . The cross-section and/or mass of the fibre sliver 44 passing through the roll nip between the draw-off rolls 42, 43 is/are determined using the spacing sensor 47 -for which purpose an apparatus analogous to that shown in Figures 3a, 3b is suitable. The spacing sensor 47 is connected to the electronic control and regulation device (not shown), which can correspond to the central computer unit 26 (see Fig. 1) . Reference letter B denotes the work direction.

In the embodiment of Figures 3a and 3b, a device for continuously registering the cross-section and/or mass of a fibre sliver combination comprising at least one fibre sliver, (for example in the arrangements shown in Figures 1 and 2), with a pair of measuring rolls 15,16. The measuring rolls may instead be the rolls 6, 8 of Figure 1 or the rolls 42, 43 of Figure 1 and 2. The shafts 15 and 16 (not shown) belonging to the shaft ends iSa and 16a, respectively, are rotatably mounted in rolling-element bearings 50 and 51, respectively, which are in turn mounted in bearing housings 52 and 53, respectively. The bearing housing 52 is immovable whereas the bearing housing 53 is arranged so as to be movable in rotation (pivotable) about an immovable rotary bearing 54 in the direction of arrows C, D. The rotary bearing 54 is fixed to an immovable support 49. The bearing housing 53 that is movable in rotation is loaded and biased by means of a spring 55, one end of which rests against an abutment 56. By this means, the bearing housing 53 and, together with it, the roll 7 or or 43 can be moved away on a substantially straight path. Integrated into the immovable bearing housing 52 is an inductive (non-contact-making) analogue spacing sensor 57, the sensor surface 57a of which is located opposite -15 -that surface 53' of the bearing housing 53 which faces it, there being present between the sensor surface 57a and the surface 53' in the operating state a variable spacing a, for example about 1 mm, which is measured by the spacing sensor 57. By this means, one of the rolls -the roll 15 -is immovable and the other roll -the roll 16 -is arranged so as to be movable away therefrom on a substantially straight path. The bearing housing 52 and the support 49 are immovably mounted on the machine frame (not shown) . In the opened state (out of operation) according to Fig. 3b, the spacing b is, for example, about 11 mm. Reference numeral 63 denotes a push crank for the purpose of opening, reference numeral 58 denotes the lead of the spacing sensor 57. Two toothed belt wheels 48a, 48b, analogous to those shown in Figure 4, are provided for driving the draw-off rolls (by way of a toothed belt which likewise is not shown in Figures 3a, 3b) In the embodiment of Fig. 4, the inductive spacing sensor 57 is integrally arranged in a recess in the upper (facing the draw-off roll 15) end region of the immovable bearing housing 52. In accordance with Fig. 5, the inductive spacing sensor 572 is integrally arranged in a groove open to one side, at a spacing from the upper (facing the draw-off roll 15) end region of the immovable bearing housing 52. In the arrangements according to Figs. 4 and 5, the spacing sensors 57 and 572 are integral components of the immovable bearing housing 52 so that the bearing housing 52 and spacing sensors 57 and 572 are constructed as one piece.

In a further embodiment shown in Fig. 6, the counterpart surface (sensed surface) located opposite the sensor surface 57a is in the form of a counterpart element 59, which is integrated into the bearing housing 53a that is movable in rotation.

-16 -In the embodiment of Fig. 7, an optical spacing sensor is immovably arranged in a recess open to one side in the immovable bearing housing 52. The spacing sensor 60 (light sensor) consists of a light transmitter 60a and a light receiver 60b. The light beam 61' emitted by the light transmitter 60a is reflected by the smooth surface 53' of the bearing housing 53 that is movable in rotation, and the reflected light beam 61' is received by the light receiver 60b. Reference numeral 62 denotes an electrical lead, by way of which the spacing sensor 60 is in communication with an evaluation device (electronic control and regulation device 26) The draw frame 1 according to Fig. 1 has, beneath the funnel 17, draw-off rolls 15, 16, which are incorporated in terms of construction into a sub-assembly and which transport, or draw, the fibre sliver 18 through the funnel.

The sub-assembly is mounted in fixed manner on a cast iron base and consists of a fixed and a movable part. Both draw-off rolls 15, 16 are driven. Monitoring of an open draw-off roll, closed draw-off roll and thick locations is carried out using the non-contact-making inductive proximity switch 57. The required measurement values resulting from the sliver sensing are determined by means of the excursion of the movable draw-off roll, with the inductive analogue sensor registering the spacings a of the draw-off rolls 15, 16. The measurement values are evaluated using a control system. Besides a non-contact-making inductive analogue sensor, other measuring systems, for example inductive or optical displacement transducers, can also be used. In accordance with the invention, firstly the measurement sensor (for example, analogue sensor or the like) is integrated as a part of a "whole" into the existing structural element and secondly the integration of the most varied sensors in principle (specific to the housing) is -17 - accomplished in existing structural parts or sub-assemblies. The sensor is accommodated in a housing which matches the contour of the existing structural sub-assembly. As a result of installation, or integration, of the sensor in the draw-off roll sub-assembly, the overall structural dimensions of the draw-off roll elements remain unchanged, subsequently resulting in a compact sub-assembly arrangement. The sensor 57 is merged with the fixed part 52 of the draw-off roll, and the movable element 53 of the draw-off roll accordingly advantageously provides the measurement tab attenuating the integrated sensor. As a result of this integration, the fixed element 52 becomes a measuring entity, the movable element 53 becomes an object of measurement and accordingly the complete sub-assembly of the draw-off rolls becomes a compact measurement system.

This integration can result in one or more of the following substantial advantages: -simple and economical sensor installation -no adjustment or settings because the mounting location is fixed by the contour of the housing -problem-free replacement -space-saving -monitoring of an open draw-off roll, closed draw-off roll and thick locations.

It is advantageous that, as a result of the integration and the associated linking of the measuring location with the supporting element of the draw-off rolls, a simple construction is achieved. Owing to the fact that the excursion of the draw-off rolls is converted into an electrical measurement value, a measurement window can be defined within a control system. Using the known measurement values of the sensor and the excursion of the movable draw-off roll it is possible to register several operating conditions. In addition to detection of a fibre -18 -sliver, it is further possible to evaluate the functions of open draw-off rolls, closed draw-off rolls, thick locations and absent sliver using software. If the measurement value is below or above a parameter previously defined in the software (sliver o.k.), a malfunction is registered and the machine switches off.

It is furthermore advantageous that the integrated type of measurement value registration can also be used at the draw-off rolls after the intake funnel. The same draw-off roll sub-assembly (groove and spring rolls) or similar can be used as measurement system with the same software evaluation.

Claims

-19 -Claims 1. An apparatus for or at a spinning room preparation machine which has a drawing mechanism for drawing out strand-form fibre material, for continuously registering the cross-section and/or mass of at least one fibre sliver, having: a pair of measuring rolls arranged to be pressed against one another, a first said roll being immovably arranged and a second said roll being arranged to be movable away therefrom; a first holding element holding said first roll; a second holding element holding said second roll; and a non-contact-making spacing sensor for measuring the spacing from a counterpart surface; wherein the sensor is associated with one of said first and second holding elements and the counterpart surface is associated with the other of said first and second holding elements, and the spacing sensor and the counterpart surface are arranged on those sides of the holding elements which face one another.
2. An apparatus according to claim 1, in which the spacing sensor is integrated into the said other holding element.
3. An apparatus according to claim 1 or claim 2, in which the spacing sensor is constructed as a separable part of the holding element.
4. An apparatus according to any one of claims 1 to 3, in which the holding element is constructed as one piece with at least one part of the spacing sensor.
5. An apparatus according to any one of claims 1 to 4, in which the spacing sensor is recessed into a space formed at ]east in part by a depression (recess) in the ho]dinq element.

-20 -
6. An apparatus according to any one of claims 1 to 5, in which the holding element incorporating the spacing sensor is a bearing element for said roll.
7. An apparatus according to claim 6 in which the bearing element is an immovable rotary bearing.
8. An apparatus according to claim 6 in which the bearing element is a movable rotary bearing.
9. An apparatus according to claim 8 in which the movable bearing element is spring-loaded.
10. An apparatus according to any one of claims 6 to 9, in which the bearing element is made of aluminium.
11. An apparatus according to any one of claims 1 to 10, in which the spacing sensor is immovable and the counterpart surface is arranged to move relative to the spacing sensor.
12. An apparatus according to one of claims 1 to 10, in which the spacing sensor is arranged to move and the counterpart surface is immovable relative to the spacing sensor.
13. An apparatus according to any one of claims 1 to 12, in which the counterpart surface is an external surface of the holding element for the other roll.
14. An apparatus according to any one of claims 1 to 12, in which the counterpart surface is a surface of a counterpart element which is associated with the other roll.
15. An apparatus according to claim 14, in which the counterpart element is integrated into the holding element for the other roll.
16. An apparatus according to any one of claims 1 to 15, in which the sensed surface is flat.
17. An apparatus according to any one of claims 1 to 16, in which the sensed surface is smooth.

-21 -
18. An apparatus according to any one of claims 1 to 17, in which the spacing sensor is a distance-measuring sensor using waves or beams.
19. An apparatus according to any one of claims 1 to 18, in which the spacing sensor is capable of registering a change in induction.
20. An apparatus according to any one of claims 1 to 19, in which the spacing measurement device is an inductive proximity initiator.
21. An apparatus according to any one of claims 1 to 20, in which the spacing sensor is an inductive displacement sensor.
22. An apparatus according to claim 21, in which the inductive displacement sensor comprises a plunger coil and a plunger core.
23. An apparatus according to any one of claims 1 to 18, in which an optical spacing sensor is employed.
24. An apparatus according to claim 23, in which the spacing sensor is a light sensor.
25. An apparatus according to claim 23 or claim 24, in which the spacing sensor is a laser sensor.
26. An apparatus according to claim 23 or claim 24, in which the spacing sensor uses visible light.
27. An apparatus according to claim 23 or claim 24, in which the spacing sensor uses infra-red light.
28. An apparatus according to any one of claims 1 to 18, in which an acoustic spacing sensor is employed.
29. An apparatus according to claim 28, in which an ultrasound spacing sensor is employed.
30. An apparatus according to any one of claims 1 to 29, in which the spacing sensor and the counterpart element are arranged in an enclosed housing.
31. An apparatus according to one of claims 1 to 30, further comprising an evaluation device arranged for -22 -communication of information relating to the sensed spacing to an electronic control and regulation device.
32. An apparatus according to any one of claims 1 to 31, in which the spacing sensor is a sensor that operates in analogue manner.
33. An apparatus according to any one of claims 1 to 32, in which the apparatus is employed for registering and/or displaying a sliver break.
34. An apparatus according to any one of claims 1 to 33, in which the spacing sensor indirectly senses the excursions of the sensed roll.
35. An apparatus according to any one of claims 1 to 34, in which the spacing sensor is employed for registering the sliver mass of an elongate, substantially untwisted fibre sliver combination.
36. An apparatus according to claim 35, in which the fibre sliver combination substantially consists of natural fibres, especially cotton, and/or synthetic fibre materials.
37. An apparatus according to any one of claims 1 to 36, in which the spacing sensor is arranged for measuring the sliver mass in the case of a continuously moving fibre sliver combination.
38. An apparatus according to claim 37, in which the registered values for the sliver mass are used for levelling out sliver mass variations in the fibre sliver combination by controlling at least one drafting element of a spinning room preparation machine in which the fibre sliver combination is being drawn out.
39. An apparatus according to any one of claims 1 to 38, in which the spinning room preparation machine is an autolevelling carding machine, a carding machine having an autolevelling drawing mechanism, a combing machine having an autolevelling drawing mechanism, or a draw frame.

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40. An apparatus according to any one of claims 1 to 39, in which registration of the sliver mass of a moving fibre sliver combination is provided at a spinning room preparation machine having a plurality of successive drafting elements for drawing out the fibre sliver.
41. An apparatus according to any one of claims 1 to 40, in which a said spacing sensor is arranged at the intake of and/or exit from a drawing mechanism of the spinning room preparation machine.
42. An apparatus according to any one of claims 1 to 41, in which the sliver mass variations are monitored at the intake and/or exit and following evaluation, where necessary, the spinning room preparation machine is switched off and/or a warning signal is emitted if values for sliver mass and/or sliver mass variations are above or below threshold values.
43. An apparatus according to any one of claims 1 to 42, in which the spacing sensor is arranged to register sliver breaks of a fibre sliver combination or of a fibre sliver of the fibre sliver combination.
44. An apparatus according to any one of claims 1 to 43, in which, on the basis of the calculated values for sliver mass, a levelling unit of the spinning room preparation machine controls at least one drafting element for intake levelling of the sliver mass variations.
45. An apparatus according to any one of claims 1 to 44, in which, on the basis of the calculated values for sliver mass, a levelling unit of the spinning room preparation machine controls at least one drafting element for outlet levelling of the sliver mass variations.
46. An apparatus according to claim 44 or claim 45, in which intake levelling and exit levelling are effected and form an interlinked control.

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47. An apparatus according to any one of claims 1 to 46, in which resonant frequency modifications are performed with a measuring frequency that is matched to the intake speed of the fibre sliver combination entering the spinning room preparation machine or to the delivery speed of the fibre sliver combination leaving the spinning room preparation machine.
48. An apparatus according to claim 47, in which the measuring frequency is matched to a defined, preferably constant, sensing length.
49. An apparatus according to claim 47, in which the measuring frequency is matched to a defined time period (time-based sensing) which is dependent on the speed of the fibre sliver combination.
50. An apparatus according to any one of claims 1 to 49, in which the sensing which registers, on each measurement, a particular portion of the fibre sliver combination is carried out in a plurality of measurements along the fibre sliver combination that are displaced with respect to one another and that overlap one another.
51. An apparatus according to any one of claims 1 to 50, in which a spectrogram or a part of a spectrogram of the fibre sliver combination is produced or supplemented using the measurement values obtained by means of the at least one spacing sensor.
52. An apparatus according to any one of claims 1 to 51, in which a spectrogram of the fibre sliver combination is recorded at the intake of and/or at the exit from the spinning room preparation machine.
53. An apparatus according to any one of claims 1 to 52, in which a plurality of fibre slivers running next to one another and, in plan view, substantially in parallel are guided through the spinning room preparation machine from the intake to the exit.

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54. An apparatus according to any one of claims 1 to 53, in which the fibre sliver combination or individual groups of fibre slivers forming the fibre sliver combination are guided through at least one funnel or through guiding elements.
55. An apparatus according to claim 54, in which there is present as a sliver guide a guiding element.
56. An apparatus according to claim 54, in which there is present as a guiding element a web guide.
57. An apparatus according to any one of claims 1 to 56, in which the movable roll is held by a movably mounted holding element comprising the spacing sensor, the movably mounted holding element being biased and adjustable by mechanical, electrical, hydraulic or pneumatic means.
58. An apparatus according to any one of claims 1 to 57, in which the axes of the draw-off rolls at the exit are horizontally arranged.
59. An apparatus according to any one of claims 1 to 57, in which the axes of the draw-off rolls at the exit are vertically arranged.
60. An apparatus according to any one of claims 1 to 59, in which control pulses are sent to a controller.
61. An apparatus according to claim 60, in which the controller adjusts the speed of rotation of at least one drive motor of the drafting draw frame in response to the signals received.
62. A spinning room preparation machine having at least one spacing sensor for measuring the sliver mass of a continuously moving fibre sliver combination, the spacing sensor being arranged as defined in any one of claims 1 to 61.
63. A spinning room preparation machine according to claim 62, comprising at least one said spacing sensor arranged at the intake of the spinning room preparation machine.

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64. A spinning room preparation machine according to claim 62 or claim 63, comprising at least one said spacing sensor arranged at the exit from the spinning room preparation machine.
65. A spinning room preparation machine according to any one of claims 62 to 64, in which the at least one spacing sensor is connected to a levelling unit, which subjects at least one drafting element of the spinning room preparation machine to open-loop and/or closed-loop control on the basis of the measurement values of the sliver mass of the fibre sliver combination.
66. A spinning room preparation machine according to any one of claims 62 to 65, in which a plurality of fibre slivers running next to one another and in parallel through the at least one spacing sensor can be registered.
67. A spinning room preparation machine according to any one of claims 62 to 66, in which a plurality of fibre slivers running next to one another and, in plan view, substantially in parallel are arranged to be guided through the spinning room preparation machine from the intake to the exit.
68. A spinning room preparation machine according to any one of claims 62 to 67, in which the spacing, from the spacing sensor, of the roll pair associated with the spacing sensor is small.
69. A spinning room preparation machine according to any one of claims 62 to 68, in which the spacing sensor is an inductive analogue sensor.
70. A spinning room preparation machine according to any one of claims 62 to 69, in which the two rolls, simultaneously in the form of draw-off rolls, are arranged immediately downstream of a funnel-shaped sliver guide, web guide or the like.

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71. A spinning room preparation machine according to any one of claims 62 to 70, in which the holding element is a housing for a rotary bearing of a roll.
72. A spinning room preparation machine according to any one of claims 62 to 71, in which at least one roll is driven.
73. A spinning room preparation machine according to any one of claims 62 to 72, in which the spacing measurement device is a distance-measuring sensor.
74. A spinning room preparation machine according to any one of claims 62 to 73, in which the spacing measurement device is in communication with an electrical evaluation device.
75. A spinning room preparation machine according to any one of claims 62 to 74, in which the spacing measurement device registers the spacings from a counterpart element located opposite the sensor surface.
76. An apparatus for monitoring a fibre sliver in a spinning preparation room machine, comprising a spacing sensor associated with a holding element of a first roll and a sensed surface associated with a holding element of a second roll, the apparatus being substantially as described herein with reference to and as illustrated by any of Figs. 1, 2, 3a and 3b, 4a and 4b, and 5 to 7.