FR2587933A1 - METHOD FOR PRODUCING HOSES COMPRISING ONE OR MORE LATERAL DERIVATION FLEXIBLES, AND FLEXIBLE SO PERFORMED - Google Patents

Abstract

PROCESS FOR MAKING A HOSE, INTENDED FOR EXAMPLE FOR THE COOLING SYSTEM OF A VEHICLE ENGINE, WITH OR WITHOUT REINFORCING LAYER AND WITH ONE OR MORE SIDE BYPASS HOSES, THE ENDS WITH REGARD TO THE HOSES MEMBERS IN A T-CONNECTION RIGID, MADE OF METAL OR PLASTIC MATERIAL, BEING MOUNTED ON THE FITTING TUBING, THEN ASSEMBLED WITH THE LATTER BY VULCANIZATION USING AN ADHESIVE PRODUCT AND UNDER THE ACTION OF HEAT AND PRESSURE. THE ENDS OF HOSE 1, 2 ARE POSITIONED BY ANNULAR ELEMENTS 4, 5 ELASTOMERES, MADE IN A PLASTIC MATERIAL PRESENTING A HOT SHRINKAGE, SLEEVES ON THE ENDS LIKE CLAMPS AND ASSEMBLIES BY VULCANIZATION WITH THESE LATTERS. THE ANNULAR ELEMENTS SIMULTANEOUSLY EXERCISE THE COMPRESSION NECESSARY FOR THE PRODUCTION OF THE ASSEMBLIES BY VULCANIZATION. IN SERVICE THEY INCREASE THE RESISTANCE OF THE BYPASS AND ITS WATERPROOFING, EVEN IN THE PRESENCE OF STRONG PRESSURE FLUCTUATIONS.

Description

The present invention relates to a method for producing

  rubber or rubber plastics, with or

  without reinforcement layers and with one or more drift hoses

  side ends, the ends facing the hoses together in a rigid T-piece made of metal or plastic being fitted on the pipes of the fitting, then assembled with the latter by

  vulcanization using an adhesive product and under

  pressure, and hoses made by such a method.

  Hoses with taps are used

  in the engine cooling system and for the

  heating of vehicles, but also in fixed installations.

  Compared to the traditional on-site assembly with the frequent need to make removable connections in a limited space, they are characterized by a significantly simplified mounting and, in use, by better fluid guidance, reliability and reliability.

  higher operating safety, and the elimination of

  subsequent damage by corrosion. It is generally not possible to forgo reinforcing layers in the hoses, as the fluid is in most cases under a high static pressure. However, this results in particular conditions

  pressure sealing and durability of

  tion. Known production methods for the direct vulcanization assembly of bypass hoses and hose

  principal, often with an external impression, give frequent

  insufficient results. A notable improvement, on the other hand, was obtained by the adoption of a rigid coupling, constituting the hose connection, and serving simultaneously as a lost core for the

  production of vulcanising assemblies according to another possibility

  known patent application (Federal Republic of Germany Patent Application No. 3,239,623). The implementation of this process

  known is, however, complex and time-consuming as a result of the need

  sity of an outdoor mold. Molded hose connections also have the inconvenience in service of uncertainties on the fatigue strength of vulcanized hose connections under the influence of strong pulsating pressure fluctuations, particularly in the critical transition zones between the flexible walls. and the

rigid pipes.

  The object of the invention is to provide economical and rapid production, with simple means, of flexible hose couplings with high stresses, and ensuring a reliable seal over time under the maximum pressures appearing in practice. According to an essential characteristic of the invention, annular elements

  flexible hoses made of an elastomeric material whose length

  The circumferential seal decreases permanently under the action of heat, is fitted with an elastic gap on the hose ends, prior to vulcanization, and then bridged to said ends by vulcanization of the adhesive product. For the implementation

  of the invention, annular elements cut on

  retractable xibles are fitted on the hose ends, then assembled with the latter by vulcanization in the state of thermal shrinkage stress, the annular elements pressed together

  exerting pressure on the hose ends for their assembly.

  Vulcanisation by vulcanisation with the connection pipes.

  By the adoption of additional ring elements, of a nature

  and particular provision, the invention creates the conditions for

  new flexible drifts, fully meeting

  to the previously stated objectives. The annular elements,

  the hose ends in the area of the corresponding tubing of the coupling, tend to contract under the influence of the

  heat of vulcanization and exert in the forced state a pres-

  directed radially inwards on the sections of

  xible supported internally by the rigid tubings, so that a perfect assembly by vulcanization is obtained without recourse

  to an outside mold. At the same time, the annular elements become

  look the same way with the hose ends from the outside; residing on the hose in the finished fitting, they behave as prestressed clamps when using the assembled hose. The couplings are consequently permanently subjected to an external compression stress which, independently of the amplitude and the variation of the static pressure of the liquid in the hose, strengthens the resistance and the stability of the connections,

  and fight against any tendency to take off. An added advantage

  is that the hoses made according to the method of the invention do not contain any metal parts, and do not

  therefore, there is no risk of corrosion in service.

  Other features and advantages of the invention will be

  better understood using the detailed description below of a

  example of embodiment of a hose comprising a flexible hose

  side view, and the single figure that schematically represents

  said hose in partial longitudinal section.

  The main hose 1 is made with a flexible hose

  2. The two hoses 1, 2 are made in one

  heat-resistant synthetic rubber, and are reinforced with

  textiles 11, 21, for example for use as flexible

  for the cooling water of a vehicle. They can be defined

  nitentially vulcanized prior to derivation production, but this is not imperative for the invention. The bypass hose 2 or both hoses 1 and 2 can also be

still in the vulcanizable state.

  For the realization of the bypass, the main hose 1 is cut by a smooth radial section, then a T-fitting 3, forming the shunt, is inserted into the joint plane. The connector 3 may be made of a metallic material, such as light alloy, zinc bronze or stainless steel alloy; for reasons of weight and cost, and taking into account possible damage by corrosion, however, a rigid plastic material is preferably used

  such as polyvinyl chloride, low pressure polyethylene, polyethylene

  amide, etc. In the illustrated embodiment, it is a T-fitting with two coaxial pipes 31, adapted to the dimensions of the main hose 1, and a pipe 32 perpendicular or at any angle with the pipes 31 and intended for the bypass hose 2 The outside diameter of the pipes 31, 32 is preferably slightly greater than the effective diameter of the corresponding hoses 1, 2, so that the latter surround the pipes.

  with a constraint resulting from the necessary flaring of the end.

  The annular shoulders 33, 34, made as auxiliaries

  mounting plates, form stops which fix the limit position of the

  and thus fix the connection range unambiguously.

  Retractable rings 4.5 elastomers are slid according to the invention on the flexible 1 and 2 fitted on the tubes 31, 32 corresponding with use of an adhesive product. The rings are cut in a known thermoplastic retractable hose, and then after flaring on the hose ends, in the position shown and using a suitable adhesive product, so as to surround said ends in the

  such as clamping rings or clamps

  and apply them to the rigid tubing of fitting 3.

  Under the action of heat during the subsequent vulcanization, the

  rings tend to contract further and thus reinforce

  pressure. Free vulcanization can therefore be done without mold

  in an autoclave or similar device.

  In the vulcanized shunt connection, the shrink rings

  tables 4,5 adhere continuously to the pipes 31, 32 of the connection 3,

  through the hoses 1, 2, and thereby exert

  continuous clamping stroke on the enclosed hose ends.

  Of course, various modifications may be made by those skilled in the art to the principle and to the devices which have just been described solely by way of nonlimiting examples, without

depart from the scope of the invention.

Claims (7)

claims   1. Method for producing a rubber or rubber plastic hose, with or without reinforcing layers and with one or more lateral shunt hoses, the facing ends of the hoses joined in a rigid T-piece, made of metal or plastic , being fitted on the pipes of the coupling,   then assembled with the latter by vulcanisation using a   adhesive and under heat and pressure, said method being characterized in that closed flexible annular elements,   made of an elastomeric material whose circumferential length   tielle decreases permanently under the action of heat, are squeezed elastically on the hose ends, before vulcanization, and then bridged to said ends   by vulcanizing the adhesive product.   2. Method according to claim 1, characterized in that   rings cut on retractable hoses are slid over the hose ends and then vulcanized   with these in the state of heat shrinkage stress.   3. Process according to claims 1 and 2, characterized in that the   pressure exerted on the ends of the hose for vulcanization assembly of the latter with the connection pipes   is produced by the annular elements fitted.   4. Flexible made by the process according to claims 1 to 3,   characterized in that the hose ends (1, 2) joined by vulcanization with the tubings (31, 32) of the connector (3) are surrounded by adhering elastomeric annular elements (4, 5). on them.   5. Flexible according to claim 4, characterized in that the axial width of the annular elements (4, 5) is equal to the length of the   corresponding pipes (31, 32) of the coupling (3).   6. Flexible according to claims 4 and 5, characterized in that the   annular elements (4, 5) have a tensile stress   residual in the circumferential direction.   7. Flexible according to claims 4 to 6, characterized in that the   annular elements (4, 5) are sections of retractable hose without reinforcement layer.