EP1762646B1 - Sealing device for machines for thermal treatment of yarns - Google Patents

Abstract

The seal head for a thermal treatment machine consists of a frame (1) fixed to a pressure chamber traversed by a conveyor belt that passes between two horizontal pressing rollers (2, 3) enclosed by sealed supports (4, 5). It is fitted with an integrated pressure or capillary lubrication system (4', 5') formed by porous elements and distributors (4", 5"). It also has lubricating fluid recovery and drainage systems (6, 7) on the cylindrical surfaces of the rollers and at their ends.

Description

The present relates to the field of the textile industry, in particular the treatment of son by means of heat treatment machines commonly called heat-setting machines and in particular the sealing heads of such machines, and relates to such a sealing head. .

The machines for heat treatment of the yarns consist essentially of a pressurized heat treatment chamber for textile yarns deposited on a conveyor belt passing through said chamber, which is closed at its two ends by sealing heads each comprising a frame attached to the pressurized vessel, a pair of horizontal rollers superposed or adjacent in a horizontal plane, which are pressed against the opposite faces of the conveyor belt and drive the material, as well as the conveyor belt, and sealing means to form a seal between the rollers and the frame.

In a known machine of this type, according to US-A-5,074,130 the horizontal rollers are provided with sealing means in the form, on the one hand, of an elongate upper element and an elongated element and each supported against a generatrix of the two rollers and, on the other hand, of lateral plates of imperviousness slidingly against the corresponding ends of the rollers. The application of sealing means, both horizontal and vertical is performed by means of actuators in the form of hydraulic cylinders at high pressure.

These sealing means are in the form, on the one hand, of an upper element and an elongated lower element and supported against generatrices of the two rollers and, on the other hand, lateral sealing plates supported by sliding way against the corresponding ends of the rollers.

Currently, the upper element and the lower element forming the longitudinal sealing means of the two rollers are each constituted by a sealing strip mounted on a pivoting support resting on the frame via a longitudinal pivoting abutment, and each cooperate with one or more corresponding actuators, while the lateral sealing plates supported by slidably against the corresponding ends of the rollers are metal plates covered, at their friction zone, a teflon plate, these plates being applied under pressure against said ends.

Due to the rotational drive of the superposed horizontal rollers, there is produced between these and the corresponding sealing means a friction with the fixed sealing parts and, thus, wear of the materials constituting these sealing means. . It follows the need to reduce the intensity of these rubs.

For this purpose, it has been proposed to produce the sealing strips constituting the longitudinal sealing means of the two rollers in a material with a low coefficient of friction or a self-lubricating material. However, these known materials do not provide a satisfactory response over time to the problem of wear of the longitudinal sealing means.

It has also been proposed to provide the longitudinal sealing means, downstream of their line of contact with the rollers, seen in the direction of rotation of said rollers, with an external lubrication device for the surface of the rollers, so that these drive the lubricant into the contact area between the fixed sealing slats and the rollers. However, as regards the inlet head of the treatment chamber, there is a risk of contacting the lubricant with the product to be treated, which could have the effect of modifying the characteristics of the treatment, or even of cause pollution of said product to be treated.

Moreover, we also know, by US-A-4,186,571 and by US-A-3,367,111 machines with adjacent horizontal rollers in a horizontal plane. The problem of sealing at rollers thus arranged is not comparable to that encountered with superposed rollers and the corresponding solutions are not reproducible in such a configuration of superimposed rolls.

The object of the present invention is to overcome these drawbacks by proposing sealing means for sealing heads of heat treatment machines, in particular for the treatment of wires, called heat-setting machines, making it possible to reduce substantially the intensity of friction and wear of the elements in contact.

For this purpose, the sealing head for wire heat treatment machines, which consists essentially of a frame attached to a pressurized chamber traversed by a conveyor belt, by a pair of superposed horizontal rollers, which are pressed against the opposite faces of the conveyor belt, and by sealing means to form a seal between the rollers and the frame, at least one of the horizontal rollers and the sealing means being connected to corresponding displacement actuators, is characterized in that the sealing means for forming a seal between the rollers and the frame are each provided with an integrated pressure lubrication means in the form of a porous body disposed between the support forming the means sealing and the horizontal rollers superimposed and being connected by its side facing said support to a distribution means of a lub said means being connected externally to the support to a pressurized lubricant supply line.

• la figure 1 est une vue éclatée en perspective d'une tête d'étanchéité conforme à l'invention ;
• la figure 2 est une vue schématique en élévation latérale, à plus grande échelle, représentant un moyen de détection d'usure des moyens d'étanchéité longitudinaux des deux rouleaux, et
• la figure 3 est une vue schématique en plan et en coupe, à plus grande échelle, représentant un moyen de détection d'usure des moyens d'étanchéité latéraux des deux rouleaux

The invention will be better understood, thanks to the following description, which refers to a preferred embodiment, given by way of non-limiting example, and explained with reference to the attached schematic drawings, in which:

• the figure 1 is an exploded perspective view of a sealing head according to the invention;
• the figure 2 is a schematic view in side elevation, on a larger scale, showing a means of detecting wear of the longitudinal sealing means of the two rollers, and
• the figure 3 is a diagrammatic plan view and in section, on a larger scale, showing a means of detecting wear of the lateral sealing means of the two rollers

The figure 1 By way of example, the accompanying drawings show a sealing head for wire heat treatment machines, which consists essentially of a frame 1 attached to a pressurized enclosure (not shown) traversed by a conveyor belt (not shown). by a pair of superposed horizontal rollers 2 and 3, which are pressed against the opposite faces of the conveyor belt, and by sealing means 4 and 5 to form a seal between the rollers 2 and 3 and the frame 1, at least one, 2, horizontal rollers and sealing means 4 and 5 being connected to corresponding displacement actuators, not shown in detail. The frame 1 not forming part of the present invention, it is represented only by its two lateral uprights receiving the rollers 2 and 3.

Moreover, as shown by figures 2 and 3 of the accompanying drawings, the sealing means 4 and 5 are applied under pressure against the corresponding surfaces of the rollers 2 and 3 respectively by means of actuators 8 and 9, which consist of jacks applying, on the one hand, against the sealing means 4, in order to effect a tilting of the latter tending to apply their active part against a longitudinal generatrix of the horizontal cylinders 2 and 3 and, secondly, against the sealing means 5 so as to press these last through levers 9 'against the ends of the rollers 2 and 3.

According to the invention, the sealing means 4 and 5 to form a sealing between the rollers 2 and 3 and the frame 1 are each provided with an integrated lubrication means 4 ', 5' under pressure. Each pressurized integrated type lubrication means 4 ', 5' is in the form of a porous body disposed between the support forming the sealing means 4, 5 and the superposed horizontal rollers 2 and 3 and is connected by its face. turned towards said support to a means 4 ", 5" for dispensing a lubricant under pressure, said means 4 ", 5" being connected, externally to the support, to a pressurized lubricant supply line.

Thus, a pressurized lubricant can be passed through the supports forming the sealing means 4, 5 on the rear face of the porous bodies forming each pressurized lubrication means 4 ', 5' and thus be distributed in said porous bodies to migrate towards their bearing face against the horizontal rollers 2 and 3. It follows that the lubricant is applied against the surfaces of the rollers 1 and 2 in contact with the sealing means 4 and 5, so that the friction between said surfaces and said sealing means is reduced.

According to another characteristic of the invention, the means 4 ", 5" for dispensing a lubricant under pressure are advantageously provided in the supports forming the sealing means 4, 5 and extend along generatrices close to those of the horizontal rollers 2 and 3, namely parallel to the longitudinal axes of said rollers in the supports forming the sealing means 4 and following a portion of a circle concentric with the axis of the corresponding rollers, close to the diameter of said axis.

Thus, a distribution of the lubricating fluid is obtained on all the surfaces in contact, so that the lubrication is carried out optimally in the form of a regular film. Indeed, by such an arrangement of the means 4 "and 5", the lubricant is automatically brought to the entire horizontal surface of the rollers 2 and 3 by the sealing means 4 and over the entire end surface of said rollers 2 and 3 by the sealing means 5. In the latter case, the centrifugal force tends to cause a radial distribution of the lubricating fluid.

The creation of a lubricating film on the rollers 2 and 3 may, depending on the lubricating fluid used, be considered as negligible with regard to a possible wetting of the treated product in the treatment chamber of the machine. It is the same with regard to the lubrication of the ends of the rollers 2 and 3. In the latter case, the film may even have a greater thickness.

However, depending on the type of lubricant used, it may be interesting, even necessary to recover said lubricant or to drain it to an evacuation. For this purpose, it may be provided, in accordance with another characteristic of the invention, as shown in FIG. figure 1 of the accompanying drawings, equipping the sealing head with means 6 and 7 for recovering and / or draining the lubricating fluid distributed respectively on the cylindrical surfaces of the rollers 2 and 3 and on the end faces of these rollers 2 and 3.

Thus, the means 6 for recovering and / or draining the lubricant fluid assigned to the horizontal rollers 2 and 3 may be in the form of scraping gutters applied by an edge against a generatrix of each roller 2 and 3 and provided with a duct 6 'of connection to a central tank or a circulation pump returning the fluid into the lubrication circuit.

In the particular case of the horizontal roller 2 coming into contact with the product to be treated, the means 6 for recovering and / or draining the lubricating fluid is preferably arranged along a generator close to the inlet of the sealing head. and therefore the conveyor belt. For the horizontal roller 3 forming the lower part of the sealing head, the means 6 for recovering and / or draining the lubricating fluid can advantageously be mounted directly on the support forming the sealing means 4, parallel to the pressurized lubrication means 4 '. Indeed, in the latter case, because the horizontal roller 3 does not come into contact with the product to be treated, the lubricating fluid can remain on said roller 3 for substantially a whole period of revolution and the means 6 is used essentially to recover the remaining fluid to prevent dispersion thereof.

The means 7 for recovering and / or draining the lubricating fluid distributed on the end faces of these rollers 2 and 3 may advantageously be in the form of one or more channels extending at least at the end of the means. sealing 5 penetrating into the processing chamber of the processing machine, these channels being connected to a recovery tank or a circulation pump. Thus, the lubricating fluid which tends to move inwardly of the chamber enters the channel or channels forming the means 7 provided for this purpose, so that it can in no way escape to the treatment enclosure.

Due to the friction between the fixed members, namely the sealing means 4 and 5 and the horizontal rollers 2 and 3, there is a more or less rapid wear of the various members in contact, depending on the conditions of use of the treatment chamber, namely the speed of the products, the internal pressure and therefore the pressure to be applied to achieve the seal, as well as the type of son.

For this purpose, it is necessary to control the wear of the fixed sealing members 4 and 5, in order to achieve their replacement in good time, that is to say before their destruction, which could lead to prolonged stops. of the machine.

According to another characteristic of the invention, in order to overcome this drawback, provision is made, in addition, to provide the sealing head with means for detecting wear of the sealing means 4 and 5, in particular their surface in contact with the longitudinal sealing rollers 2 and 3, both along their generatrix and at their ends, which consist of at least one displacement sensor 10, 11 assigned to the application means said sealing devices against the surfaces of the horizontal rollers 2 and 3.

The figures 2 and 3 For this purpose, the appended drawings show schematically, respectively in side elevation and in plan view, the application of the sealing means 4 and 5 against the corresponding surfaces of the rollers 2 and 3.

According to a preferred embodiment of the invention, the displacement sensors 10 and 11 assigned respectively to the sealing means 4 and 5 are each in the form of at least one end-of-travel contact cooperating with a cam 12. , 13 provided on a piston rod or a transmission rod of the actuator 8, 9 for pressurizing application of the sealing means 4, 5, this cam 12, 13 coming into contact with the sensor 10, 11 after a displacement corresponding to an optimal wear of the sealing means 4 and 5. The terms optimum wear of the sealing means 4 and 5 mean wear of these means 4 and 5 further to ensure sealing while avoiding a deterioration of a contact surface.

The sensors 10 and 11 cooperating with the cams 12 and 13 make it possible to detect the decrease in the thickness of the sealing means 4 and 5, as a result of their wear, by taking into account the corresponding displacement of the piston rod or transmission of the actuators 8 and 9 and the stroke of the cam 12 or 13 thereof is preset to correspond to optimum wear, so that upon reaching the corresponding wear threshold, a preventive maintenance replacement is to be expected.

For this purpose, according to another characteristic of the invention, the end-of-travel contacts corresponding to optimum wear are advantageously connected to a luminous and / or audible signaling means and / or by display warning the operator of the necessity of the replacement of the sealing means.

For reasons of safety, it may be provided, according to another characteristic of the invention to provide each actuator 8, 9 sealing means 4, 5 of a complementary means of extreme wear detection 14, 15 detecting a maximum displacement travel of the sealing means 4, 5 towards the corresponding surfaces of the horizontal rollers 2, 3 and delivering an automatic stop signal of the machine and an alarm of detection of an ultimate level of wear.

Preferably, the additional means of extreme wear detection 14, 15 are also made in the form of end-of-stroke contact and cooperate respectively with cams 16, 17 also provided on the piston rod or the transmission rod of the actuators 8 , 9. The end-of-travel contacts forming these additional means of extreme wear detection 14, 15 are also connected to visual and / or audible alarm and / or display means, as well as to a cut-off contact. emergency of all power supplies of the machine.

The cams 16, 17 are comparable to those 12, 13 and have simply with respect to the latter a greater length of travel of the piston rod or the transmission rod of the actuators 8, 9.

Thus, it is possible to detect at first a normal wear of the sealing means 4 and 5 and to carry out the corresponding maintenance work in a perfectly predictable time and, in the event that this first period has been forgotten, cause automatic shutdown of the machine, to avoid any risk of destruction of the sealing head.

According to an alternative embodiment of the invention, not shown in the accompanying drawings, the wear detection means 10, 11 and the additional means of extreme wear detection 14, 15 can be replaced either by an inductive detector, or by a ground contact mounted on a support arm or an intermediate actuating means of the sealing means 4, 5 and cooperating with one or more end-of-travel contacts, either by a visual detector or by a combination of the visual detector and of a mass contact.

In the case of using a ground contact, it can be provided that the mechanical element of the latter successively actuates two end-of-travel contacts respectively of normal wear and extreme wear and that its displacement is visualized, for example by highlighting warning and warning colors.

Thanks to the invention, it is possible to very significantly improve the operation of a son heat treatment machine sealing head by providing a better seal between the movable elements and the fixed elements, while ensuring less wear sealing means.

In addition, the wear of said sealing means can be perfectly controlled, so that preventive maintenance can be performed and that the operational safety of the sealing head and as a result of the whole machine can be totally assured.

Of course, the invention is not limited to the embodiment described and shown in the accompanying drawings. Modifications are possible, particularly from the point of view of the constitution of the various elements or by substitution of technical equivalents, without departing from the scope of protection determined by the claims.

Claims (18)

1. Sealing head for machines for the thermal treatment of threads, which essentially comprises a frame (1) fixed to a pressurised chamber traversed by a conveyor belt, a pair of horizontal superimposed rollers (2 and 3), which are pressed against the opposite surfaces of the conveyor belt, and sealing means (4 and 5) for forming a sealed closure between the rollers (2 and 3) and the frame (1), at least one (2) of the horizontal rollers and the sealing means (4 and 5) being connected to corresponding actuators for movement (8 and 9), characterised in that the sealing means (4 and 5) for forming a sealed closure between the rollers (2 and 3) and the frame (1) are each provided with a pressurised integrated lubricating means (4', 5'), which is in the form of a porous body arranged between the support forming the sealing means (4, 5) and the superimposed horizontal rollers (2 and 3) and is connected by its surface facing said support to a means (4", 5") for distributing a lubricant under pressure, said means (4", 5") being connected, externally to the support to a supply line for lubricant under pressure.
2. Sealing head according to claim 1, characterised in that the means (4", 5") for distributing a lubricant under pressure are provided in the supports forming the sealing means (4, 5) and extend along generatrices near those of the horizontal rollers (2 and 3), namely parallel to the longitudinal axes of said rollers in the supports forming the sealing means (4) and along a portion of a circle concentric to the axis of the corresponding rollers, near the diameter of said axis
3. Sealing head according to any one of claims 1 and 2, characterised in that it is provided with means (6 and 7) for the recovery and/or drainage of lubricating fluid distributed respectively over the cylindrical surfaces of the rollers (2 and 3) and on the end surfaces of these rollers (2 and 3).
4. Sealing head according to claim 3, characterised in that the means (6) for the recovery and/or drainage of the lubricating fluid belonging to the horizontal rollers (2 and 3) is in the form of scraping gutters applied by one edge against a generatrix of each roller (2 and 3) and provided with a pipe (6') for connection to a central reservoir or a circulation pump returning the fluid into the lubrication circuit.
5. Sealing head according to any one of claims 3 and 4, characterised in that the means (6) for recovery and/or drainage of the lubricating fluid is disposed along a generatrix near the inlet of the sealing head and thus of the conveyor belt.
6. Sealing head according to any one of claims 3 and 4, characterised in that the means (6) for recovery and/or drainage of the lubricating fluid is mounted directly on the support forming the sealing means (4), parallel to the integrated lubrication means under pressure (4').
7. Sealing head according to claim 3, characterised in that the means (7) for recovery and/or drainage of the lubricating fluid distributed over the end surfaces of these rollers (2 and 3) is in the form of one or several channels extending at least to the end of the sealing means (5) entering the treatment chamber of the treatment machine, said channels being connected to a recovery reservoir or to a circulation pump.
8. Sealing head according to any one of claims 1 to 7, characterised in that it is provided with means for detecting wear (10, 11) of the sealing means (4 and 5), in particular of their surface in contact with the longitudinal sealing rollers (2 and 3) both along their generatrix and at their ends.
9. Sealing head according to claim 8, characterised in that the wear detection means (10, 11) consist of at least one movement or displacement detector (10, 11) belonging to the application means of the sealing devices against the surfaces of the horizontal rollers (2 and 3).
10. Sealing head according to claim 9, characterised in that the movement detectors (10 and 11) belonging respectively to the sealing means (4 and 5) are each in the form of at least one end of path contact interacting with a cam (12, 13), provided on a piston rod or a transmission rod of the actuator (8, 9) for pressurising the application of the sealing means (4, 5), this cam (12, 13) coming into contact with the detector (10, 11) after a movement or displacement corresponding to the optimum wear of the sealing means (4 and 5).
11. Sealing head according to claim 10, characterised in that the end of path contacts corresponding to optimum wear are connected to a light and/or audio and/or display signal means warning the operator of the need to replace the sealing means.
12. Sealing head according to any one of claims 8 to 11, characterised in that each actuator (8, 9) of the sealing means (4, 5) is provided with a supplementary means for detecting extreme wear (14, 15) detecting a maximum movement or displacement path of the sealing means (4, 5) in the direction of corresponding surfaces of horizontal rollers (2, 3) and delivering an automatic stop signal of the machine and an alarm for the detection of an ultimate level of wear.
13. Sealing head according to claim 12, characterised in that the supplementary means for detecting extreme wear (14, 15) are also in the form of end of path contacts and interact respectively with cams (16, 17) also provided on the piston rod or the transmission rod of the actuators (8, 9).
14. Sealing head according to any one of claims 12 and 13, characterised in that the end of path contacts forming the supplementary means for detecting extreme wear (14, 15) are connected to visual and/or audio and/or display alarm means as well as to an emergency cut-off contact of all the power supplies of the machine.
15. Sealing head according to any one of claims 12 to 14, characterised in that the wear detection means (10, 11) and the supplementary means for detecting extreme wear (14, 15) are replaced by an inductive detector.
16. Sealing head according to any one of claims 12 to 14, characterised in that the wear detection means (10, 11) and the supplementary means for detecting extreme wear (14, 15) are replaced by a ground contact mounted on a support arm or an intermediate actuating means of the sealing means (4, 5) and interacting with one or more end of path contacts.
17. Sealing head according to any one of claims 12 to 14, characterised in that the wear detection means (10, 11) and the supplementary means for detecting extreme wear (14, 15) are replaced by a visual detector.
18. Sealing head according to any one of claims 12 to 14, characterised in that the wear detection means (10, 11) and the supplementary means for detecting extreme wear (14, 15) are replaced by a combination of a visual detector and a ground contact.

Images