FR2809982A3 - PROCESS AND APPARATUS FOR PRODUCING A TUBULAR ELEMENT, AND RUBBER TUBULAR ELEMENT WITH TEXTILE REINFORCEMENT - Google Patents

Abstract

The invention relates to the production of tubular elements. It relates to a method which comprises the provision of a tubular support element (4), the extrusion of a first annular layer (7) of silicone rubber on the tubular support element (4), the arrangement by shaping or mounting of a tubular mesh or braided member (9) on the first layer (7) of silicone rubber, the extrusion of a second annular layer (11) of silicone rubber on the first layer (7) and the mesh or braided member (9), and the separation of the tubular support element (4) from the internal surface of the tubular rubber element of silicone thus produced. Application to the tubular elements of motors.

Description

The present invention relates to a method and an apparatus

  reil for producing tubular elements made of silicone rubber having a textile reinforcement, which can be used for example as air outlet ducts of internal combustion turbocharged engines for vehicles

engine cules.

  Given the increasingly severe conditions imposed for the reduction of unused space in the engine compartment, the air outlet pipes of turbocharged engines of motor vehicles must be able to withstand very high working temperatures,

of the order of 250 C.

  Conventional tubes or pipes made of an elastomeric material, for example EPDM copolymer, cannot

  withstand such high temperatures.

  Recently, therefore, tubes made of textile fabric impregnated with silicone rubber and wound up have been used to form tubular elements which, after being placed on shaping elements which give them

  the desired configuration, are vulcanized.

  This process for producing tubular elements is

  killed from textile-reinforced silicone rubber is extremely expensive as it is a production process

almost entirely manual.

  The subject of the invention is therefore the provision of a method and an apparatus which allow the profitable and technically convenient production of tubular products of the aforementioned type made of silicone rubber having a

  textile reinforcement, automatically.

  These and other objects are achieved according to the invention by a process for producing a tubular element made of silicone rubber having a textile reinforcement, which comprises the following steps: the provision of an element support tubular whose external surface is not suitable for connection to a silicone rubber, the extrusion of a first annular layer of silicone rubber on the support tubular element, the arrangement by shaping or mounting a tubular mesh or braided member on the first layer of silicone rubber, the extrusion of a second annular layer of silicone rubber on the first layer

  and the mesh or braided organ, and the separation of the ele

  tubular support for the internal surface of the element

  tubular silicone rubber thus produced.

  These objects are also achieved according to the invention thanks to

  to an apparatus for producing a tubular element of rubber

  silicone cauldron having a textile reinforcement, which comprises: a first extrusion station intended to extrude a first annular layer of silicone rubber on a tubular support element whose external surface is not suitable for bonding to silicone rubber, a position of

  mesh formation placed downstream of the first extrusion station

  sion and intended to ensure the formation by creation or mounting of a tubular mesh or braided member on the first layer of silicone rubber, and a second extrusion station placed downstream of the mesh formation station and intended to extrude a second annular layer of silicone rubber on the first layer and the organ

mesh or braided.

  These objects are also achieved according to the invention thanks to a tubular element formed of silicone rubber having a textile reinforcement, produced by the use of one at

  less of the preceding claims.

  Other characteristics and advantages of the invention

  will be better understood on reading the description which will

  follow exemplary embodiments, made with reference to the accompanying drawings in which: Figure 1 is a schematic plan view of an apparatus or installation for producing tubular elements according to the invention; Figure 2 is a side elevational view of part of the apparatus or installation of Figure 1; Figures 3 to 6 are sections along lines III-III to VI-VI of Figure 2; and Figure 7 is a section through a tubular product made of textile-reinforced silicone rubber

product according to the invention.

  We first refer to Figures 1 and 2; an instal-

  Production lation of tubular products formed of silicone rubber with textile reinforcement according to the invention

  has several positions placed successively.

  At a feed station designated by the reference 1 in the drawings, a roller 3 mounted on a support frame 2 can rotate around a substantially horizontal axis. A section of a tubular support element 4 formed for example of a vulcanized elastomeric material, for example of EPDM copolymer, is wound on the roller 3. This tubular support element has one end 4a (FIG. 2) which is retained at the neighborhood of the axis of rotation of the roller 3 and, as described below, is intended to be connected, during operation, to an apparatus (not shown) for blowing a stream of gas, in particular air, in

the tubular support element 4.

  Downstream of the feed station 1, is arranged a

  first known type of extrusion station 5. This extru-

  sion comprises (Figure 2) an extrusion head 6 through which the tubular support member 4 passes and in which a first annular layer of unvulcanized silicone rubber, designated by the reference 7 in Figure 4, is extruded to the external surface of the tubular support element. The semi-finished tubular product 8 which leaves the extrusion head 6 reaches a mesh forming station, indicated by the reference 19 in FIGS. 1 and 2. At this station, a tubular "braided" or mesh fabric bearing the

  reference 9 in figure 5 is formed on the semi-finished product

finished 8.

  The tubular product 10 exiting from the forming station 19

  tion of meshes goes through a drawing station 21 (Figures 1

  and 2) then reaches a second extrusion station 12.

  A second annular layer of silicon rubber

  cone, bearing the reference 11 in FIG. 6, is extruded onto the semi-finished product 10 at the extrusion station 12. This second layer 11 of silicone rubber is perfectly bonded to the underlying layer 7, through the meshes of

braiding 9.

  The semi-finished product 13 leaving the second extrusion station 12 then passes into a cooling bath

  designated by reference 14 in Figure 1.

  Downstream of the cooling bath 14, the product 13 reaches a station 15 intended to cut the product 13 to length (FIG. 1), in which the product 13 is divided into

  several successive parts of predetermined lengths.

  In a manner not shown in the drawings, the parts of the semi-finished product 13 are then transferred to a

next maturing station.

  At the end of the aging stage, the tubular element

  support area 4 is separated from each part of the product

  semi-finished 13. Part of the semi-finished product as indicated

  qué by the reference 16 in Figure 7, constituted practi-

  only a tubular element of silicone rubber in which the textile tubular meshes or the braiding

  9 are incorporated, is thus obtained.

  The parts of the semi-finished product 16 are then placed on elements of forming members of known type so that they take the desired shape, then are subjected to a

vulcanization.

  After vulcanization, the tubular elements of rubber

  army silicone cauldron can be removed from the items

  formatting and are ready to use.

  So that the separation of the tubular element from

  port 4 of the tubular silicone rubber element surrounding it is easy, the external surface of the element

  support tube 4 advantageously has a film of a material

  non-stick coating, for example talc.

  Of course, various modifications can be made by those skilled in the art to the methods, apparatus and elements which have just been described only by way of

  non-limiting example without departing from the scope of the invention.

Claims (10)

  1. Method for producing a tubular element (16) consisting of a silicone rubber having a textile reinforcement (9), characterized in that it comprises the following stages: the provision of a tubular support element (4) whose external surface is not suitable for connection to a silicone rubber, the extrusion of a first annular layer (7) of silicone rubber on the tubular support element (4), the arrangement by placing in the form or mounting of a tubular mesh or braided member (9) on the first layer (7) of silicone rubber, the extrusion of a second annular layer (11) of silicone rubber on the first layer (7 ) and the mesh or braided member (9), and the separation of the tubular support element (4) from the internal surface of the tubular rubber element of silicone (16) thus produced.   2. Method according to claim 1, characterized in that, during the extrusion of the first and second silicone layers (7, 11) at least, a gas is blown into   the tubular support element (4).   3. Method according to one of claims 1 and 2,   characterized in that the tubular support element (4) is   formed from a vulcanized elastomeric material.   4. Method according to claim 3, characterized in that the tubular support element (4) carries a film placed on its external surface and intended to prevent adhesion to the silicone rubber.   5. Apparatus for producing a tubular element (16) of silicone rubber having a textile reinforcement (9), characterized in that it comprises: a first extrusion station (5) intended to extrude a first annular layer ( 7) of silicone rubber on a tubular support element (4) whose external surface is not suitable for connection to the silicone rubber, a station (19) for forming meshes placed downstream of the first extrusion station (5 ) and intended to ensure the formation by creation or mounting of a tubular mesh or braided member (9) on the first layer (7) of silicone rubber, and a second extrusion station (21) placed downstream of the station (19) for forming meshes and intended to extrude a second annular layer (11) of silicone rubber on   the first layer (7) and the mesh or braided member (9).   6. Apparatus according to claim 5, characterized in that it comprises a cooling bath (14) placed downstream of the second extrusion station (12) and intended to receive   the semi-finished product (13) from the second extrusion station sion (12).   7. Apparatus according to claim 6, characterized in that it comprises, downstream of the cooling bath (14), a cutting station (15) intended to cut the tubular element   (16) of silicone rubber and the associated tubular element   support cie (4) in parts of predetermined lengths.   8. Apparatus according to any one of claims   to 7, characterized in that it further comprises a device for blowing a gas into the tubular element of support (4).   9. Apparatus according to claim 8, characterized in that it comprises a station (1) for supplying tubular support elements (4) of the first extrusion station (5), the supply station (1) comprising a rotary roller (3) on which is wound the tubular support element   (4), a first end of the tubular support element   port (4) being retained in the vicinity of the axis of rotation of the   roller (3) and being connected to the blowing device.   10. Tubular element (16) formed of silicone rubber having a textile reinforcement (9), characterized in that it is produced by using at least one of the previous claims.