GB2157386A - Multiple fluid circuit connector - Google Patents

Abstract

A multiple connection system for fluid circuit conduits, particularly applicable to heat exchange circuits in motor vehicles, comprises a rigid tubular insert 4 having a plurality of nozzles, 6, 7 the end portions of which are a press fit into the conduits 2a, 2b, 3 to be connected, the insert and an end portion of the conduits, being covered at least in part by a moulded rubber or synthetic resin casing 5. <IMAGE>

Description

SPECIFICATION Multiple connection system for fluid circuit conduits The invention relates to a multiple connection system for fluid circuit conduits. The invention has particular but not exclusive application to heat exchange circuits in motor vehicles, Fluid circuits such as heat exchange circuits in vehicles normally comprise a plurality of con duits, which may be rigid or flexible, connect ing the various parts of the engine or appara tus, each conduit having its pertinent section.

Motor vehicle manufacturers have to build several circuits into a vehicle, particularly for water. These circuits extend from the radiator to the engine and are also in connection with other circuits associating the radiator and/or engine with the vehicle interior heating or with other parts to be heated.

The current trend in motor vehicle manufac ture is to have the engines operating at very high temperatures, whereby very high termal gaps are avoided.

Therefore, the circuits through which the high temperature water flows must be formed by elements meeting strict requirements rela tive their resistance to bursting fatigue and diametral deformation under a particular load, so as to avoid the appearance of leaks. To such end, the conduits normally used are made from rubber or synthetic resins, gener ally provided with textile reinforcement in both cases.

Nevertheless, when making connections be tween conduits, there is the risk of causing weak areas in which the abovementioned re quirements are not met and which, therefore, are not as strong and watertight as they should be.

One known way of making these connec tions takes place during the vehicle assembly process, i.e. it is performed in the motor vehicle manufacturer's own workshops. This way of making connections requires a wide range of parts, such as clamps of different diameters and conduits of different diameters and lengths also, causing supply problems and involving a lengthening of the assembly time.

Therefore, the manufacturers ask for com plete circuits, with all the connections already made, so that the circuit forms a unit to be mounted in the vehicle. This complete circuit must, obviously, meet the strict requirements mentioned above.

One of the ways of making these connec tions consists of making a generally circular hole in a conduit, plugging the end of another conduit in this hole, inserting cores in the conduit portions to be connected, moulding the outer portion of said conduit portions with rubber or the like and removing the cores.

This system has the drawback that the perimeter of the hole, where the two conduits are juxtaposed, is covered only with the moulding rubber, which is weaker than the conduit material, whereby this hole perimeter is a weak point in the connection.

It is an object of the invention to provide a multiple connection system for overcoming the aforementioned drawbacks.

According to the present invention there is provided a multiple connection system for fluid circuit conduits comprising a rigid tubular insert having a plurality of nozzles; each nozzle being coupled to a conduit by means of a press fit engagement; and a casing moulded from rubber or synthetic resin covering at least in part said insert and an end portion of the conduits.

The invention will be described now by way of example only with particular reference to the accompanying drawings. In the drawings: Figure 1 is a perspective view of a series of conduits provided with connection systems according to the invention; Figure 2 is an elevation view of a connection between two conduits; Figure 3 is a cross sectional view on the line Ill-Ill of Figure 2; Figure 4 is a cross sectional view along the line IV-IV of Figure 3; Figure 5 is a perspective view of an insert; Figure 6 is an axial section view of a purge connection for a circuit; Figure 7 is a view similar to Figure 6 of an alternative embodiment; Figure 8 is a sectional view similar to Figure 4, showing the system provided with rings; and Figure 9 is a cross sectional view of a mould in which the casing is moulded, the mould containing a system according to the invention.

The present multiple connection system 1 is appropriate for making communication between a plurality of conduits. For example, such communication may be provided between two conduits or between two parts 2a, 2b of the same conduit 2; or to provide a branch (conduit 3) from a conduit 2a, 2b; or to provide a purge means; or for any combination of the above.

The system 1 comprises a rigid tubular insert 4, preferably made from polyamide with glass fibre reinforcement. Thus the insert is at least as strong as and usually stronger than the conduits forming the circuit. The insert comprises a plurality of nozzles 6,7 and although the examples show inserts generally of T shape, having three nozzles, inserts may also be made with a larger number of nozzles.

e.g. crosses, H-shapes, or other forms. prefer ably the end portions 6a, 7a of the nozzles are provided with annular grooves 8 facilitating the attachment of the corresponding conduit 2, 3.

The nozzles 6, 7 of the insert are press fitted into the interior of the conduits 2, 3 to be connected and, after a moulding operation, the assembly is provided with a casing 5 formed by synthetic resins or rubber such that said casing 5 covers at least in part said insert and an end portion 21 of the conduits, in which there is included the perimeter of the mouth 22 of the conduits. With said casing any cracks between the conduits and the insert are tightly sealed and the joint between the conduits and insert is also improved.

In an alternative embodiment, rings 23 may be placed around the end portion 21 of the conduits tightly pressing the conduit against the nozzle 6, 7 of the insert 4; the rings are in turn covered by said casing 5.

These rings serve to counteract an extreme situation in which the conduit 2a is exceptionally deformed and widened as shown schematically by the phantom lines of Figure 8. If this widening reaches the mouth 22 of the conduit, the pressure inside the conduit would affect the casing 5 which, as said above, is not as strong as the conduits and insert.

Therefore a leak could occur, which leak is prevented by the presence of the rings.

The process for preparing the multiple connection system 1 will be apparent from the foregoing description, namely, one end portion of the nozzles 6, 7 of an insert 4 is press fitted in the conduits 2, 3 to be connected.

The plug-in fit may be reinforced with the rings 23 and thereafter the assembly is fitted in a mould 25 for performing the moulding operation providing the casing covering 5.

To provide for the correct centering of the connection system in the mould 25, the insert may be provided with generally radial tabs 9 (Figures 3 and 5) adapted to hold the insert immobile during the moulding of the casing 5.

Nevertheless, the tabs 9 are not indispensable. If the moulding operation is carried out in such a way that the moulding material is supplied to the moulding chamber in two substantially opposite directions, the assembly is held sufficiently motionless and centred without the need for the tabs 9. Figure 9 shows the passages 26 and 27 providing the said opposite directions.

Figures 6 and 7 illustrate particular embodiments in which the connection system 1 is provided with an insert 4 in which the nozzle 7' is used for a purge means for the circuit in which the system is mounted. To such end, the nozzle 7' is provided with an inner thread 10 for holding a plug 11 having a flexible washer 12 and an axial groove 13, allowing the fluid flowing through the conduits 2, 3 to flow out when the plug 11 is backed off, without it being necessary fully to remove the plug. In the embodiment of Figure 7, the casing 5 covers the side wall of the threaded nozzle 7' and forms a small overhang 27 replacing the resilient washer 12 of Figure 6.

Claims (8)

1. A multiple connection system for fluid circuit conduits, comprising a rigid tubular insert having a plurality of nozzles; each nozzle being coupled to a conduit by means of a press fit engagement; and a casing moulded from rubber or synthetic resin covering at least in part said insert and an end portion of the conduits.

2. A multiple connection system as claimed in claim 1, wherein the end portion of each conduit is provided with a resilient ring tightly pressing the conduit against the nozzle of the insert, said ring being covered in turn by said casing.

3. A multiple connection system as claimed in claim 1 or claim 2, wherein said insert is provided with generally radial tabs adapted to hold the insert immobile during the moulding of said casing.

4. A multiple connection system as claim in claim 1, wherein said insert is provided with an internally threaded nozzle adapted to receive a plug.

5. A multiple connection system as claimed in claim 4, wherein said plug is provided in the portion thereof for insertion in the threaded nozzle with an external longitudinal groove adapted to place the interior of the insert in communciation with the exterior without it being necessary to remove the plug fully.

6. A multiple connection system as claimed in claim 4, wherein there is a resilient washer between said threaded nozzle and said plug.

7. A multiple connection system as claimed in claim 4, wherein said casing covers the side wall of said threaded nozzle forming an overhanging portion adapted to act as resilient nozzle.

8. A multiple connection system substantially as hereinbefore described with reference to and as shown in the accompanying drawings.