FR2853037A1 - Joint connector for oven, has immobilization unit with tabs, where ratio of inner diameter of connector and exterior diameter of envelope is maintained in predetermined range by tubular core of envelope - Google Patents

Abstract

The connector has an immobilization unit with rectangular tabs (52) cut out in central part of the connector. The tabs extend in longitudinal direction and in opposed longitudinal direction with respect to walls in which the tabs are cutout. The ratio of inner diameter of the connector in its rest state and exterior diameter of an envelope (20) is maintained in 0.85 or in 0.90 but below 1 by a tubular core of the envelope. An independent claim is also included for a method of realizing a joint connector for oven.

Description

1 2853037

  The present invention relates to thermal seals for ovens and in particular, but not exclusively, pyrolysis ovens in which very high temperatures prevail on the order of 4500 ° C. to 500 ° C. during cleaning operations by pyrolysis, and more particularly fittings covering the ends of the joint to form a closed contour.

  Such thermal seals are most often mounted on the oven door and are in contact with the surroundings of the front face of the oven.

  These oven gaskets include a tubular casing or outer sheath which is woven, braided or knitted, of wire with high thermal resistance and normally made of glass fibers. Such a glass fiber casing or sheath is relatively soft and is not able to maintain its tubular shape. For this reason, the tubular casing or outer sheath receives an elastic tubular core of metal wire, for example stainless steel, to maintain the tubular shape of the casing necessary to ensure good thermal insulation. Such a seal is described in document FR-A-2,306,397.

  In place of a tubular core, it has also been proposed to incorporate into the envelope or sheath a core in the form of metallic wires interlaced with glass fiber wires of the envelope. These metal wires are preferably arranged in helical or other turns and extend circumferentially and longitudinally with respect to the envelope or sheath. Such a seal is described in document FR-A2.389.81 1.

  In both cases, the tubular core or the wire constitutes a spring means for elastically maintaining the generally cylindrical shape of the envelope or sheath.

  To fix the oven seals to the oven door or its surroundings, fixing or fastening means are incorporated. To this end, the tubular part can be provided with a fastening band attached or formed from the same woven, braided or knitted structure as the envelope or the sheath. Bulb seals are also known. Fastening means of this type are described and illustrated in the two aforementioned French documents.

  2 2853037 More recently, metal fasteners have been adopted in place of fixing bands or bubles. These metal fasteners are sometimes dissociated from each other, sometimes linked together by a single wire or the like. These fasteners extend transversely beyond the casing 5 or sheath of the joint itself. The document FR-A2.819.303 describes separate metallic fasteners spaced along the tubular element and the document EP-A-193.364 describes a set of fasteners forming part of a single metallic wire.

  The ends of the envelope or sheath must be connected to form a seal with a closed contour, and in particular with four corners, to adapt to the arrangement of orifices intended to receive the fasteners or a housing intended to receive other means of attachment.

  Several solutions for connecting the ends of joints are known. None is entirely satisfactory.

  We know in particular the French document N0 01.16837 according to which the connector comprises a tubular element in glass fibers woven from the same fabric used to make the envelope of the joint. The assembly is not easy. First, this tubular connector is threaded over one end of the joint envelope. The free ends of the tubular member are coupled at a junction. Then, the tubular connector is repositioned around the junction to hide it. In addition to the number of manipulations required for this method of assembly, means must be provided to maintain the position of the connector relative to the junction. To this end, fasteners should be located at the junction and / or on either side of the fitting to prevent movement. According to another embodiment described in this document, the connector is a metal tube with accordion corrugations whose position relative to the ends of the joint must also be limited by fasteners arranged on either side thereof.

  There is also known a so-called "thumbnail" connector also made of fabric, the middle part of which surrounds the casing on either side of the junction between these two ends and transverse superimposed tabs extending outwards, substantially in the same direction as the 3 2853037 metal fasteners. To ensure the coupling of the two ends on the one hand and the immobilization of the sticker fitting relative to the ends of the joint on the other hand. This fitting is sewn to the casing in the transition zone between the middle part and the tabs. This sewing cannot be automated and is therefore relatively expensive to perform. Likewise, the diameter of the seal at the connection is substantially reduced compared to the nominal diameter of the envelope or sheath, this reduction being due to the seaming through the two thicknesses of the envelope at the transition zone.

  The object of the present invention is to overcome, or even eliminate, the drawbacks mentioned above.

  According to the present invention, the connection of the oven seal is constituted by an element intended to elastically clamp the ends of the envelope.

  In practice, the connection is made at least partially of elastic material.

  In the idle state, the connector has a diameter slightly less than the diameter of the envelope, so that when the connector is placed on the ends of the joint, the latter is under stress.

  According to an embodiment of the present invention, the connector 20 comprises a rolled metal blade. In practice, both in the rest state and under stress on the ends of the joint, the circumferential extent of the blade is equal to or greater than 3600, thus ensuring continuity all around the junction between the ends of the envelope.

  Preferably, the coiled metal strip has on its inner surface means for immobilizing the connector longitudinally relative to the envelope. Such means may be constituted by oblique elastic tongues, punctures, spikes, or even a rough surface treatment, the roughness of which is capable of clinging to the wires or filaments of the envelope.

  Preferably, the metal blade is made of stainless steel.

  According to one embodiment, the blade is bi-stable having an elongated waiting state and a coiled state for inserting the ends of the envelope.

  4 2853037 According to a second aspect of the invention, there is provided an oven seal with a closed contour, of the type comprising a woven, braided or knitted tubular envelope resistant to high temperatures and an elastic metal wire core of tubular shape and arranged at the interior of the envelope, either incorporated into the woven, braided or knitted structure of the envelope extending circumferentially and longitudinally, the connector tightening the ends of the envelope according to the first aspect of the invention.

  According to a third aspect of the invention, there is provided a method for producing an oven gasket connection, according to which an elastic metallic core is either introduced inside an envelope or incorporated into the woven structure. , braided, or knitted from the envelope, the ends of the envelope are brought together and the ends are tightened elastically by means of the connector.

  The characteristics and advantages of the invention will become apparent from the description which will follow by way of example with reference to the appended drawings in which: - Figure 1 is a partial elevation and exploded view to illustrate the structure an oven seal; FIG. 2 is a perspective view to illustrate the assembly of two ends of the tubular casing by means of a connector according to a first embodiment; - Figure 3 is a perspective view of the ends of the envelope resiliently tightened by a connector according to the embodiment of Figure 2; - Figure 4 is a perspective view to illustrate the mounting of an oven seal having a connector according to the present invention in the oven door; - Figure 5 is a longitudinal sectional view of a section of the joint comprising the two ends clamped by the connector, as mounted in the oven door - Figure 6 is a second embodiment of the connector according to the invention comprising another type of longitudinal immobilization means of the connector; 2853037 - Figure 7 is a perspective view of another embodiment of the connector consisting of a bi-stable metal blade in its deployed state; - Figure 8 is a perspective view corresponding to Figure 7 o the metal blade is in its wound state.

  According to one embodiment of an oven seal 10 illustrated in FIG. 1, the envelope 20 of the seal 10 is braided and made of glass fibers. The process for producing the envelope by braiding, weaving or knitting is known per se. It can also be woven or knitted and / or made of other natural or synthetic fibers capable of withstanding, for example, temperatures of the order of 450'-500'C when the joint is intended for a pyrolysis cleaning oven. .

  To maintain the generally cylindrical shape of the envelope, a tubular core 30 having an open wick structure as illustrated is inserted into the envelope 20 and extends substantially over the entire length thereof, it that is to say between its ends. As a variant, the core can be incorporated into the structure of the envelope and preferably consists of one or more helical metal wires arranged in turns. The seal 10 further comprises a plurality of fasteners 40, as illustrated, formed of a single wire and linked together. The fasteners 40 in the form of a lozenge-shaped open loop are known in themselves and linked together by sections 41 of straight wire. The wire element 42 comprising a plurality of fasteners 40 linked to each other is introduced into the casing 20 and the fasteners 40 are introduced between the interlaced wires, so that they protrude transversely relative to the casing 20 The spacing and the arrangement of the fasteners 40 conform to the orifices 82 formed in the door 81 of the oven 80, or alternatively, in the surrounding which cooperates with the door 81 (see FIG. 4).

  To assemble the seal 10, the two ends of the envelope 20 are brought together and placed end to end, as illustrated in FIG. 2, and a connector is positioned at the ends 21, 22 juxtaposed with the envelope 20 According to this embodiment, the connector 50 is a metal blade, in particular made of stainless steel, with a width of 4 to 8 cm, capable of being rolled up on itself to tighten each of the ends of the envelope 20.

  The blade is therefore longitudinally split with respect to the envelope. As illustrated, the connector 50 comprises means 51 capable of immobilizing it longitudinally relative to the ends of the envelope. In this embodiment, the immobilization means consist of rectangular tongues 52 cut in the central part of the blade and extend obliquely to the wall in which they are cut, respectively in a longitudinal direction and in the opposite longitudinal direction. The tongues 52 can then immobilize the ends of the envelope 20 in opposite directions. As a variant, the core can be incorporated into the structure of the envelope and preferably made up of one or more helical metallic wires.

  Thanks to its elasticity, the connector 50 closes on itself with an overlap zone between 900 and 1800. It goes without saying that the overlapping portion is devoid of tongues to ensure that this portion cooperates intimately with 1 5 the portion that it underlies. In the idle state, the diameter is slightly less than the nominal diameter of the casing 20 and in practice the ratio between the inside diameter of the fitting in the quiescent state and the outside diameter of the casing 20 maintained by its core. 30 is equal to or greater than 0.85, and preferably 0, 90 and less than 1. Leakage at the connection in contact with the door or its surroundings is therefore minimized.

  Likewise, the ratio between the outside diameter of the fitting in place on the ends of the casing and the outside diameter of the casing held by its tubular core is preferably equal to or greater than about 0.9 and less than 1.0 .

  Another immobilization means 51A is illustrated for a connector 50A consisting of a plurality of spaced punctures 53, as illustrated in FIG. 6, or pins (not illustrated), or even a rough surface treatment whose roughness is able to cling to the wires or filament of the envelope 20.

  Although the use of a metal blade as a connector is preferred, other structures are possible, and in particular a woven split tubular element incorporating elastic metallic filaments ensuring that the tubular element closes on itself and s' hangs on the surface of the ends of the envelope.

  7 2853037 The connector can also be produced in the form of a bistable blade 50B, as illustrated in FIGS. 7 and 8. Such a blade has a first deployed position (see FIG. 7) allowing a plurality of bistable blades to be stacked before being rolled up (see figure 8) individually 5 at the joint ends to be assembled. Such a bistable blade can also be provided with any means of immobilization (not illustrated) of the connector on the envelope of the joint, as described and illustrated for the other embodiments.

  Once assembled, the seal 10 can be mounted, for example on the door 81 of an oven 80. To do this, the fasteners 40 projecting from the seal 20 are presented opposite the orifices 82 formed in the door and then introduced into these orifices 82 passing through a zone of greater width of the diamond-shaped loop, so that the fasteners 40 are held elastically in the perforated plate of the door. Such an assembly 1 5 also makes it easier to replace the used seal. A section of gasket assembled and mounted on the perforated plate of the door is illustrated in Figure 5.

  Of course, the present invention is in no way limited to the embodiments chosen and shown, but encompasses any variant within the reach of ordinary skill in the art, including those relating to the state of the art, described or not in the this request.

8 2853037

Claims (16)

  1. Oven joint connection with closed contour, of the type comprising a woven, braided or knitted tubular envelope resistant to high temperatures and an elastic core either of tubular shape and arranged inside the envelope, or incorporated in the woven, braided or knitted structure of the envelope extending circumferentially and longitudinally, the connector being intended to cover the juxtaposed ends of the envelope, characterized in that the connector (50, 50A, 50B) is able to tighten said elastic elastically ends.   1 0 2. Oven joint connection according to claim 1, characterized in that it is made at least partially of elastic material.   3. Oven joint connection according to claim 1 or 2, characterized in that it is longitudinally split.   4. Oven joint connection according to any one of claims 1 5 1 to 3, characterized in that it consists of a rolled metal blade.   5. Oven joint connection according to any one of the preceding claims, characterized in that, in the rest state, the circumferential extent of the blade is equal to or greater than 3600.   6. Oven joint connection according to claim 5, characterized in that, under stress on the ends of the envelope, the circumferential extent of the blade is equal to or greater than 3600.   7. Joint fitting according to any one of the preceding claims, characterized in that the ratio between the inside diameter of the fitting in the idle state and the outside diameter of the envelope maintained by its tubular core is equal or greater. 0.85 and less than 1.0.   8. Joint fitting according to any one of the preceding claims, characterized in that the ratio between the inside diameter of the fitting in the idle state and the outside diameter of the envelope maintained by its tubular core is equal to or greater than 0.9 and less than 1.0.   9. Joint fitting according to any one of the preceding claims, characterized in that the ratio between the outside diameter of the fitting in place on the ends of the casing and the outside diameter 9 2853037 of the casing held by its tubular core is equal to or greater than about 0.9 and less than 1.0.   10. Oven joint fitting according to any one of the preceding claims, characterized in that it is made of stainless steel.   he. Furnace gasket connector according to any one of the preceding claims, characterized in that the internal surface of the connector comprises means (51, 51A) for opposing the longitudinal displacement of the connector with respect to the ends of the envelope.   1 0 12. Oven joint connection according to any one of claims 4 to 11, characterized in that the metal blade has a plurality of tongues inclined towards the inside of the wound blade.   13. Oven joint connection according to claim 12, characterized in that a first part of the tongues extends towards one of the ends of the coupling while a second part of the tongues extends towards the opposite end of the connection.   14. Oven joint connection according to any one of claims 4 to 11, characterized in that the metal blade has a plurality of punctures (51A) extending towards the inside of the wound blade. 15. Oven joint connection according to any one of claims 4 to 11, characterized in that the metal blade has a plurality of pins extending towards the inside of the wound blade.   16. Oven joint connection according to any one of the preceding claims, characterized in that it consists of a bistable blade (50B) having an elongated waiting state and a wound state for inserting the ends of the 'envelope.   17. Oven seal with closed contour, of the type comprising a woven, braided or knitted tubular envelope (20) resistant to high temperatures and an elastic core either of tubular shape (30) and disposed inside the envelope, is incorporated into the woven, braided or knitted structure of the envelope extending circumferentially and longitudinally, the fitting tightening the ends of the envelope conforming to any one of the claims 1 to 16. 1 0   18. Oven joint with closed contour according to claim 17, characterized in that the tubular core (30) produced in metallic wick is disposed inside the tubular casing.   19. Oven joint with closed contour according to claim 17, characterized in that the core comprises at least one helical turn in the form of metal wires incorporated in the woven, braided or knitted tubular envelope.   20. A method of producing a furnace gasket, in which an elastic tubular core made of a metallic wick is introduced inside a woven, braided or knitted tubular envelope resistant to high temperatures, the ends are brought together. the envelope and the ends are tightened elastically by means of the connector in accordance with one   any of claims 1 to 16.