FR2723596A1 - Monitor for lap development at drawing unit rollers - Google Patents

Abstract

Appts. to monitor the development of a lap at least at one pair of rollers working a sliver, esp. in a drawing unit, has a common operating unit (39) for all the pressing systems (23a-23d), to trip a switch (41, 42).

Description

The invention relates to a device for monitoring the formation of a loop on at least one pair of rollers which guide a composite fiber ribbon in a spinning machine, in particular a drawing bench, constituted by a pressure roller and by a driving roller, and comprising support members for pressing the pressing roller against the driving roller, as well as at least one switching member for stopping the driving roller during the formation of a loop on the pressure roller and / or on the drive roller, as well as members for receiving the support members and the pressure roller, by means of which the pressure roller can be lifted from the drive roller.

In a known device, a pressure roller support is fixed by means of a screw to a tilting bracket. In order to be able to exert pressure on the pressure roller bearing, a pressure piston is provided in a guide bearing housed in the support of the pressure roller, on which a support lever exerts pressure by means of a pressure spring located between the support lever and the piston. In addition, the piston carries a displacement element which can be moved and fixed by means of a fixing screw, and on which a displacement cam is provided. In addition,
The displacement element carries a contact ring which is displaceable and which can be fixed by means of a fixing screw. In addition, a guide rod was fixed on the tilting stirrup by means of a support element made of an insulating material.

This guide rod is used to receive a contact sleeve which is arranged in displacement on the guide rod so that the friction between the guide rod and the contact sleeve is such that the contact sleeve cannot be moved by its own weight. A contact cam is provided on the contact sleeve which is located between the displacement cam and the contact ring. Here, the contact socket is connected for example to a positive electrical pole, and the contact ring is connected to a negative electrical pole. These two poles are connected to an electrical control.

When a loop is formed in a pressure roller or lower roller, the corresponding pressure roller is moved away from the lower roller located opposite the resistance of the piston, so that the piston is moved up until the switching element touches the switching socket. Thanks to this, the above-mentioned switching function is exercised, whereupon the drawing bench is immediately stopped in the control unit. In this case, the distance between the switching element and the contact edge corresponds to the switching path of the piston. Simultaneously, this distance corresponds to the thickness of the loop produced. It will be understood that this distance is chosen to be as small as possible, in order to stop the drawing bench as quickly as possible when the loop is formed. Correspondingly, the switching voltage cannot have high values, in order to avoid a spark between the switching element and the switching socket also when the distance is very small. When the pressure roller has to be rectified on the surface guiding the composite fiber ribbon, for any functional reason known per se, the diameter of this pressure roller is necessarily reduced. On the other hand, the tilting caliper is always fixed in the same operating position, regardless of such a reduction in diameter, so that the piston adjusts, when it exerts pressure against the bearing, automatically half the difference in the diameter of the ground pressure roller. During this adjustment, the switching sleeve is also adjusted to the same value automatically on the guide rod by means of the cover-shaped termination element, or the switching sleeve on the piston rod via the sliding sleeve . Thus, the distance is automatically shifted to the setpoint each time the pressure roller is adjusted.

Before lifting the tilt lever away from the stop, the operator undoes the fixing of the support lever by means of the handle, so that the spring is discharged. When the friction between the piston and the guide bearing is chosen so that the piston does not move, after the lifting of the tilting caliper, downwards by its own weight, the displacement cam, and thus also the contact sleeve, then reach the position again, after the new positioning of the support lever in its operating position.

However, when the pressure roller has to be reduced in diameter, for reasons of wear, the displacement cam moves the contact sleeve downwards, when the support lever is fixed in its operating position, until 'that the pressure roller rests on the lower roller. This is why the distance between the contact cam and the contact ring is kept at its original value.

The known device is expensive in several respects due to its production. A separate monitoring device is provided for each pair of rollers, that is to say that for the drawing bench a plurality of monitoring devices is required. In addition, it is disadvantageous that each individual monitoring device is complex in construction, and requires considerable production and assembly work. Finally, it is inconvenient to have to adjust exactly a plurality of distances between the switching element and the switching socket, respectively, in order to prevent an electrical spark also when the distance is very small.

Consequently, the underlying objective of the invention is to provide a device of the type described in the introduction, which avoids the drawbacks mentioned, which is in particular easy to produce and to assemble, and which reliably allows monitoring of 'formation of a loop on the spinning machine, in particular a drawing bench.

This objective is achieved by the fact that the support members are connected to a common actuating element which actuates the switching member.

Thanks to the fact that the support members are connected to a movable common element, a monitoring device for more than one pair of rollers of the machine is produced in a simple manner as regards its structure. According to the invention, the switching member is actuated by a movable element, so that each pair of rollers must act only on one element, whereby a considerable simplification in terms of construction and assembly is achieved. In combination with this, it suffices to actuate a single switching member for the entire machine from the movable common element, whereby advantages are also achieved with regard to construction and assembly. Finally, the monitoring device according to the invention is much simpler in terms of its construction than each of the multiple known individual monitoring devices.

Suitably, the switching member has a predetermined switching path, which is constant regardless of the position of the support member.

Preferably, the switching path can be adjusted so that it remains constant regardless of the diameter of the pressure roller and / or the drive roller. Advantageously, the support piston is a push rod urged by a pneumatic or hydraulic force. Preferably, the support piston is a push rod urged by the force of a spring. Judiciously, the actuating element can be tilted radially relative to the rollers. The actuating element is preferably movable in the longitudinal direction. The actuating element is judiciously an elastic traction element. Preferably, the actuator is a cord, a ribbon, or the like. The actuating element is advantageously stressed by a force, for example by a spring. Preferably, the actuating element is fixed in position by one end. According to a second preferred embodiment, the cord extends around a cord return roller. Judiciously, the actuating element is returned by rollers, cylinders, return studs, or the like. Preferably, the idler rollers are mounted by means of a sliding bearing, for example a ball bearing. Advantageously, a movable return element is arranged on a respective piston. Preferably, the tilting of the movable deflection roller corresponds to the thickness of the loop produced. Judiciously, the actuating element is a rod, an arc, or the like. Preferably, each movable idler roller is associated with at least one stationary idler roller. Advantageously, each stationary support device for receiving the support members is associated with two stationary return rollers. Preferably, the movable idler roller and the stationary idler rollers are arranged at a distance (b) from each other during operation. Judiciously, the movable idler roller is arranged on the side of the stationary idler roller which is diverted from the pressure roller. Preferably, the actuating element is connected to a movable switching member. Advantageously, the movable switching member comprises a metal surface. Preferably, the movable switching member cooperates with a fixed switching member. Judiciously, the fixed switching device is a measuring device. Preferably, the measuring device is a proximity switch. An inductive proximity switch is preferably provided. Preferably, a monitoring device is provided on both sides of the stretching mechanism.

The invention will be explained in more detail below, with reference to embodiments illustrated in the drawings.

The figures show: fig. 1 a side view of a drawing bench comprising the device according to the invention; fig. the a top view on the return, the cord attachment and its bias by a spring; fig. lb the cord, with the switching member and the inductive proximity switch; fig. 2a part of fig. 1 in section along the line A-A (fig. 1), with the device according to the invention and under pneumatic stress; fig. 2b a view according to FIG. 2a, the upper roller being raised; fig. 3a a section through the drawing bench during operation, viewed in the axial direction of the rollers, comprising the device according to the invention and under mechanical stress; fig. 3b a view according to FIG. 3a, the upper roller being raised; and fig. 4 a drawing bench in perspective, comprising a drawing mechanism for the device according to the invention; fig. 5 another embodiment which comprises a pivoting rod as an actuating element.

According to fig. 1, the stretching mechanism is designed as a "4 of 3" stretching mechanism, that is to say that it is constituted by three lower rollers I, II, III (I lower output roller, H central lower roller, III lower input roller) and by four upper rollers 1, 2, 3, 4. The stretching of the fiber composite tape 38 takes place in the stretching mechanism. The stretch consists of the pre-stretch and the main stretch. The roller pairs 4 / III and 3 / II form the pre-stretch field, and the roller pairs 3/11 and 1, 2/1 form the main stretch field.

The lower output roller I is driven by a main motor 59 (fig. Lb), and thus determines the output speed. The lower input roller III and the central lower roller II are driven by an adjustment motor 60 (fig. Lb) and by interchangeable pre-stretching rollers. The upper rollers 1 to 4 are pressed by pressing elements 5 to 8 (biasing device) in pressing arms 13a, 13b (only the arm 13a is illustrated) against the lower rollers I, n, III, and receive their drive thus via friction cooperation. The direction of rotation of the rollers I, II, Here; 1, 2, 3, 4 is illustrated by bent arrows. The composite fiber ribbon 38 which consists of several fiber ribbons 53a to 53c (fig. 4) flows in direction G. The lower rollers I, II, III are mounted in bearings 11 (see figs. 2a, 2b) which are arranged on the machine frame 12. Two tilting stirrups 13a, 13b (only one is illustrated in fig. 1) are used for the mobile reception of two respective pressure roller supports 14 (only one is illustrated in figs. 2 and 3) to receive the pressure rollers 1, 2 , 3, or 4. On each pressure roller support 14, two stationary return rollers 34a, 34b are arranged; 35a, 35b; 36a, 36b or 37a, 37b, the centers of which have a distance a from each other. On each push rod 23 a movable idler 29, 30, 31 or 32 is arranged. The respective distance between the centers of the two stationary idlers and the center of the movable idler during operation is designated by the reference b. All the movable and stationary idler rollers are surrounded on their outer face by a cord 39. The cord 39 is fixed non-detachably by one of its ends on a stud 47. In the region upstream of the pair of input rollers III / 4, the cord 39 is returned around a cord return roller 48. The other end of the cord 39 attacks one end of a tension spring 49 (see fig. La), the other end of which is fixed on a fixed mounting element 50. In this way, the four movable push rods 23a to 23d are connected to a single actuating element, which actuates the switching member (leaf spring 41, inductive proximity switch 42 ). When a single movable guide roller is deflected during the formation of a loop, the respective switching member 41, 42 is actuated.

According to fig. la, a monitoring device is provided on both sides of the stretching mechanism. The cords 39a and 39b are returned around a cord return roller 48a or 48b. One end of the cords 39a and 39b is fixed to a tension spring 49a or 49b. The tension springs 49a, 49b are fixed in fixed mounting elements 50a or 50b.

In correspondence with fig. 2a, 2b, the pressure roller support 14 is constituted by an upper part 15 and a lower part 16. The upper part 15 forms a cylinder unit comprising a cylinder chamber 17, in which a piston 18 is guided by means of a push rod 23 in a sliding sleeve 20. The push rod 23 is guided in a sliding sleeve 24 which is in turn arranged in the lower part 16.

A bearing 25 which receives the pressure roller 4 extends in a passage opening 26 of the pressure roller support 14. In doing so, the push rod 23 is supported by its other end on the bearing 25, in order to establish the compression cited between the pressure roller 4 and the drive roller III.

A membrane 29 divides the cylinder chamber 17 with respect to pressure. In order to produce the pressure in the upper part of the cylinder chamber 17, it can be supplied with compressed air by means of a compressed air connection. The lower part of the cylinder chamber 17 is evacuated by a vent hole.

In addition, there is provided in the lower part 16 a passage opening 27 through which extends a stud 28 which is fixed by one of its ends in the push rod 23. At its other end, a roller is provided. movable return 31, which is mounted in a ball bearing. Two other studs 33a, 33b (only 33a is illustrated) are fixed so as to pass through the lower part 16; on one end of the studs, the stationary idler rollers 36a, 36b are respectively arranged (only the roller 36a is illustrated), which are mounted on a ball bearing.

The studs 28, 33a, 33b are arranged parallel to the axis of the rollers 4, m.

During operation, the distance between the mobile deflection roller 31 and the stationary deflection rollers 36a, 36b amounts to the value b according to FIG. 2a.

During operation, after having guided a composite ribbon of fibers 38 on the lower rollers I, H, III, the tilting stirrup 13 is tilted into the working position shown in FIG. 1, and it is fixed in this position, so that the pressure rollers 1,2,3,4 can press the composite fiber tape 38 on the lower rollers I, H, III. This pressing occurs on the one hand by the fact that the push rods 23a to 23d respectively rest on the corresponding bearing 25a to 25d, and on the other hand by the fact that an overpressure has been established in the chamber above the membrane 29.

When a loop 38a is formed on a pressure roller (1, 2, 3, 4) or on a lower roller (I, II, III), the corresponding pressure roller 4 is moved in direction A away from the lower roller III located opposite, against the resistance of the push rod 23 in position 4 '(fig. 2b), so that the bearing 25 also, and thus the push rod 23 are moved in direction A. Thus, the movable guide roller 31 arranged on the stud 28 is simultaneously displaced in direction A, according to FIG. 2b. The distance b (fig. 2a) thus increases to the distance c (fig. 2b). As shown in fig. lb. the cord 39 and the driver 40 fixed on the cord 39 are thus pulled in direction C. Consequently, the leaf spring 41 arranged by one of its ends on the driver 40, is moved in direction E. Thus, the metal surface of the leaf spring 41 approaches the inductive proximity switch 42, so that a switching function is established, whereby a control unit 43 causes the bench to stop immediately drawing (drive motors 59, 60). Preferably, an inductive displacement sensor is provided comprising a movable loop and a movable core. In this case, the difference in the distances c - b corresponds to the thickness d of the formed loop 38a.

When it is necessary to rectify, for functional reasons, the pressure roller 1, 2, 3, 4 on the surface which leads the composite fiber ribbon 38, the diameter of this pressure roller is reduced. The piston 18 and thus the push rod 23 adjust automatically when they exert pressure against the bearing 25, by half the difference in diameter. During this adjustment, the position of the movable guide roller 31 is also automatically adjusted by the same value.

Figs. 3a, 3b illustrate a mechanical solution, with which one can perform essentially the same functions as with the solutions illustrated in figs. 2a, 2b. In order to be able to exert pressure on the pressure roller bearing 25, a push rod 23 is provided in a guide bearing 24 housed in the pressure roller support 14; on one end of the guide bearing, a plate 44 exerts pressure by means of a pressure spring 45 situated between the plate 44 and the push rod 23. In order not to let the pressure spring 45 rest directly against the push rod 23, an intermediate element 46 is provided between the pressure spring 45 and the push rod 23.

Fig. 4 shows in a drawing bench, for example the high-performance drawing bench HS 900 from the company Trützschler, that the round pots 51 are arranged below the ribbon inlet 52, and the supply ribbons 53a to 53c are drawn on rollers and brought to the drawing mechanism. After passing the stretching mechanism 54, the stretched ribbon 55 arrives in the rotary deposition head 56 of the potting machine, and is deposited in rings in the pot 57. The stretching mechanism 54 and the rotary deposition head 56 are protected against contact by the cover 61 of the stretching mechanism. The window 58 which is provided there allows observation of the deposition and drawing operation.

In FIG. 5, a rod 63 is provided as a common actuating element, which, by one of its ends, is pivotally mounted in the direction of the arrows H, I, on a hinge 64. The rod is arranged above and at a distance from the bolts 67, 68, 69 which are fixed respectively to the push rods 23b, 23c, 23d. The rod 63 rests on a stationary stop element 66.

The stationary inductive proximity switch 42 is disposed under the other end of the rod 63. When forming a loop, the rod pivots in the direction of arrow I, and the proximity switch 42 provides a pulse electronic control of the machine.

Claims (32)

Claims 1. Device for monitoring the formation of a loop on at least one pair of rollers (4 / 1in) guiding a composite ribbon of fibers (38) in a spinning machine, in particular a drawing bench, constituted by a roller pressing (4) and by a driving roller (III) and comprising support members (23; 23a to 23d; 23 ') for pressing the pressing roller against the driving roller, as well as at least one switching member (41, 21) for stopping the driving roller during the formation of a loop on the pressure roller and / or on the driving roller, as well as members for receiving the support members and the pressure roller, means by which the pressure roller can be lifted from the driving roller, characterized in that the support members (23; 23a to 23d, 23 ') are connected to a common actuating element (39) which actuates the switching member (41, 42). 2. Device according to claim 1, characterized in that the switching member (41, 42) has a predetermined switching path which remains constant regardless of the position of the support member. 3. Device according to either of claims 1 and 2, characterized in that the switching path can be adjusted so that it remains constant regardless of the diameter of the pressure roller and / or the drive roller. 4. Device according to any one of claims 1 to 3, characterized in that the support member is a push rod (23; 23a to 23d; 23 ') biased by a pneumatic or hydraulic force (18, 26 ). 5. Device according to any one of claims 1 to 4, characterized in that the support member is a push rod (23; 23a to 23d; 23 ') urged by the force of a spring (45) . 6. Device according to any one of claims 1 to 5, characterized in that the actuating element (39) can be moved radially (A, B) relative to the rollers (1, 2, 3, 4; I , II, III). 7. Device according to any one of claims 1 to 6, characterized in that the actuating element (39) is movable in the longitudinal direction (C, D). 8. Device according to any one of claims 1 to 7, characterized in that The actuating element is a traction element. 9. Device according to any one of claims 1 to 8, characterized in that the actuating element is a cord (39), a ribbon, or the like. 10. Device according to any one of claims 1 to 9, characterized in that the actuating element (39) is biased by a force, for example by a spring (49; 49a, 49b). 11. Device according to any one of claims 1 to 10, characterized in that the actuating element (39) is fixed stationary (47) at one end. 12. Device according to any one of claims 1 to 11, characterized in that the cord (39) extends around a cord return roller (48; 48a, 48b). 13. Device according to any one of claims 1 to 12, characterized in that the actuating element (39) is returned by rollers, cylinders, return studs, or the like (29, 30, 31, 32; 31 '; 34a, 34b, 35a, 35b, 36a, 36b, 37a, 37b). 14. Device according to any one of claims 1 to 13, characterized in that the return rollers (29, 30, 31, 32; 31 '; 34a, 34b, 35a, 35b, 36a, 36b, 37a, 37b) are mounted respectively by means of a sliding bearing, for example by a ball bearing. 15. Device according to any one of claims 1 to 14, characterized in that there is provided a movable return element respectively on a push rod (23; 23a to 23d; 23 '). 16. Device according to any one of claims 1 to 15, characterized in that the movement of the movable deflection roller (29, 30, 31, 32; 31 ') corresponds to the thickness (d) of the formed loop ( 38a). 17. Device according to any one of claims 1 to 16, characterized in that the actuating element is a rod, an arc or the like. 18. Device according to any one of claims 1 to 17, characterized in that there is associated with each movable idler roller (29, 30, 31, 32; 31 ') at least one stationary idler roller (34a, 34b; 35a, 35b; 36a, 36b; 37a, 37b). 19. Device according to any one of claims 1 to 18, characterized in that we associate with each support device for the reception of the support members (5 to 8; 14; 16) two stationary return rollers ( 34a, 34b; 35a, 35b 36a, 36b; 37a, 37b). 20. Device according to any one of claims 1 to 19, characterized in that the mobile deflection roller (29, 30, 31, 32; 31 ') and the stationary deflection rollers (34a, 34b; 35a, 35b; 36a, 36b; 37a, 37b) are arranged, during operation, at a distance (b) from each other. 21. Device according to any one of claims 1 to 20, characterized in that the movable return rollers (29, 30, 31, 32; 31 ') are arranged on the side of the stationary return rollers (34a, 34b; 35a, 35b; 36a, 36b; 37a, 37b), which is diverted from the pressure roller (1 to 4). 22. Device according to any one of claims 1 to 21, characterized in that the actuating element (39, 40) is connected to a mobile switching member (41). 23. Device according to any one of claims 1 to 22, characterized in that the movable switching member (41) has a metal surface. 24. Device according to any one of claims 1 to 23, characterized in that the movable switching member (41) cooperates with a fixed switching member (42). 25. Device according to any one of claims 1 to 24, characterized in that the fixed switching member (42) is a measuring device. 26. Device according to any one of claims 1 to 25, characterized in that the measuring device is a proximity switch (42). 27. Device according to any one of claims 1 to 26, characterized in that an inductive proximity switch (42) is provided. 28. Device according to any one of claims 1 to 27, characterized in that there is provided an inductive displacement sensor comprising a movable loop and a movable core. 29. Device according to any one of claims 1 to 28, characterized in that there is provided on both sides of the stretching mechanism (54) a monitoring device. 30. Device according to any one of claims 1 to 29, characterized in that the common actuating element is a rod (63), arc or the like, pivotally mounted at one of its ends on a hinge (64 ). 31. Device according to claim 30, characterized in that the measuring device (42) is arranged at the other end of the rod (63). 32. Device according to one of claims 30 or 31, characterized in that there is provided a stop element (66) for the rod (63).