GB2037921A

GB2037921A - Improvements in or Relating to Flexible Hoses

Info

Publication number: GB2037921A
Application number: GB7937747A
Authority: GB
Original assignee: Pneumatiques Caoutchouc Manufacture et Plastiques Kleber Colombes SA
Current assignee: Pneumatiques Caoutchouc Manufacture et Plastiques Kleber Colombes SA
Priority date: 1978-10-31
Filing date: 1979-10-31
Publication date: 1980-07-16
Also published as: DE2943665C2; IT7969119A0; IT1119443B; GB2037921B; FR2440511B1; FR2440511A1; DE2943665A1; IT7953696V0

Abstract

This invention relates to hoses of flexible material having a lateral take- off device comprising a tubular stub having an internal socket 2 abutting the internal face of the wall of the hose 3 and an external clamping washer 4. The hose is reinforced locally at the take-off point by means of a non-extendable ring 5 encircling the hose over an axial length which is at least equal to the diameter of the socket 2. <IMAGE>

Description

SPECIFICATION Improvements In or Relating to Flexible Hoses The present invention relates to flexible hoses of rubber or similar material of the type used in cooling or air conditioning circuits for automotive vehicles and comprising at one point on their wall a lateral take-off device either for bleeding or for connection of a branch hose with a smaller diameter.

The take-off device comprises generally a rigid tubular stub having a circular socket abutting against the internal face of the hose around the opening for passage of the stub and a clamping washer abutting against the external face of the pipe.

One of the difficulties encountered with devices of this type results from the fact that the clamping surfaces of the stub and the washer are relatively small and from the fact that the rubber wall of the hose which is flexible and resilient has a tendency to escape outwards between the clamping surfaces. On the other hand, to obtain a sure and sealing-tight attachment it is necessary for the clamping to be quite strong but without being exaggerated so as not to thin down or damage the wall of the hose.

Finally, when the hose in use is submitted to an internal, continuous or pulsating pressure, it is necessary, on the one hand, for the wall of the hose which is gripped between the stub and the washer to resist sliding and creep which tend to disengage it from between the clamping surfaces and, on the other hand, for it to be resistant to small cracks and fissures which can occur near the clamped part.

It is thus an object of the invention to increase the safety of such clamping and the viability of the attachment.

Accordingly, the invention consists in a hose of flexible material having a lateral take-off device comprising a tubular stub having an internal socket abutting the internal face of the wall of the hose and an external clamping washer, wherein the hose is reinforced locally at the take-off point by means of a non-extendable ring encircling the hose over an axial length which is at least equal to the diameter of the socket.

In order that the invention may be more clearly understood, reference will now be made to the accompanying drawings which show several embodiments thereof by way of example and in which Fig. 1 is a cross-section through a first embodiment, Fig. 2 is an axial section through the sembodiment ofFig. 1, Fig. 3 is a cross-section through a second embodiment, Fig. 4 is an axial section through the embodiment of Fig. 3, Fig. 5 is a cross-section through a third embodiment, Fig. 6 is an axial section through the embodiment of Fig. 5, Fig. 7 is a cross-section through a fourth embodiment, Fig. 8 is an axial section through the embodiment of Fig. 7, Fig. 9 shows a detail, Figs. 10 and 1 1 are cross-sections through fifth and sixth embodiment, Fig. 12 is a cross-sections through a seventh embodiment, Fig. 13 is an axial section through the embodiment of Fig. 12 and Fig. 14 shows a detail.

Referring to the drawings the general means forming the subject of the invention consists in local reinforcement of the hose at the location of the take-off device by means of a non-extendable ring encircling the hose over a sufficient axle length a and at least equal to the diameter d of the circular socket of the stub referred to above.

In this way the part of the hose encircled by the ring is prevented from expanding radially or extending axially when the pipe is put under pressure or when force is exerted on the stub member. This part of the wall of the hose is thus protected from or largely relieved of the tension forces which tend to disengage it from the takeoff device or cause fractures near this device.

In the embodiments shown, the take-off device comprises a tubular stub 1 having a circular socket 2 abutting against the internal faces of the wall of the hose 3 round the opening made laterally in the wall of the hose for passage of the stub. The part of the stub going through to the outside of the hose accommodates a clamping washer 4 permitting the pipe wall to be gripped near the stub opening. The clamping washer 4 can be fixed directly onto the tubular body of the stub 1 if it is, for example, a washer with clips known per se or it can be clamped by means of a threaded screw onto the stub or any other equivalent means.

In the case of Figures 1 and 2, the hose 3 is encircled locally near the take-off device by means of a rigid tubular ring 5 having an internal diameter substantially equal to the external diameter of the hose 3 and an axial length a of about 1.5 times the diameter dofthe circular socket 2 of the stub member. This ring has an opening 6 for the passage of the stub 1 and rounded or raised edges.

After mounting the stub 1 on the hose and clamping of the washer 4, the ring 5 is slid axially on end of the hose and the stub 1 is placed in the opening 6 of the ring due to the flexibility of the hose wall. In use, the clamping washer 4 bears against the interior of the ring 5 which slightly flattens the hose round the stub whilst the rest of the part encircled by the hose is applied against the interior of the ring.

As a modification, the ring 5 can have a flat portion round the opening 6 for passage of the stub so that the clamping washer 4 finds a flat support inside the ring 5.

In another embodiment, the opening 6 of the ring 5 has a larger diameter than that of the clamping washer 4 so as to permit the mounting of the stub 1 and the positioning of the washer 4 after placing the ring on the hose.

In Figures 3 and 4, the ring 5 is once again a rigid tubular ring which is positioned by axially sliding it on to the hose. It has a flat area 7 with a surface at least equal to that of the washer 4 round the opening 6 for passage of the stub 1. In this case, the edge of the opening made in the hose for passage of the stub 1 is clamped between the circular socket 2 of the stub and the internal flat face of the ring 5. The clamping washer 4 is applied to the external face of the flat portion 7 of the ring.

In Figs. 5 and 6, the ring 5 is constituted by a flexible and non-extensible band, for example of twilled material, wound at least once around the hose 3, the ends of this band being able to more or less cover each other. An adhesive or selfvulcanizing band can be used. The opening for passage of the stub 1 can be bored into the hose 3 after positioning the band. The clamping washer 4 is preferably placed above the band.

In Figures 7, 8, 9, 10, the ring 5 is formed by a flexible band of thin metal having an opening 6 for passage of the stub 1 half way along, lengthwise and attachment means such as a bent-over edge 8 with a notch 9 and a T-shaped tongue at 10 at its extremities (Fig. 9). This type of ring 5 can be positioned before putting on the clamping washer 4 which is then located outside (Fig. 7, 8) or after putting on the washer 4 which is then located inside the ring (Fig. 10). However a passage opening 6 with a diameter slightly larger than that of the clamping washer 4 so as to make it possible to place and clamp this washer against the pipe after positioning the ring 5 can be provided for.

In Figures 1 1 and 12, the ring 5 is a flexible band of thin metal with an opening 6 at each extremity for attachment of the said extremities of the band on the exterior of the stub 1. The clamping washer 4 can be placed under the superposed extremities of the band or over the superposed extremities.

Figure 13 shows another embodiment in which the ring 5 and the clamping washer are combined into a single piece. In this case the edges of the opening 6 of the ring are cut away to form clips 1 1 (Fig. 14) which are overlayed on the tubular part of the stub 1 when the latter is engaged, from within the hose 3, in the opening 6 of the ring. This same combination of the ring 5 and the means for clamping or retention of the stub can also be used in the other embodiments described previously when the ring is of rigid material such as metal.

Claims

1. A hose of flexible material having a lateral take-off device comprising a tubular stub having an internal socket abutting the internal face of the wall of the hose and an external clamping washer, wherein the hose is reinforced locally at the takeoff point by means of a non-extendable ring encircling the hose over an axial length which is at least equal to the diameter of the socket.

2. A hose as claimed in claim 1, wherein the ring is a closed ring axially engaged on the pipe and having an opening for passage of the stub.

3. A hose as claimed in claim 1, wherein the ring is a flexible open band having at least one opening for passage of the stub and means for securing its extremities.

4. A hose as claimed in claim 1, wherein the ring is a flexible open band having a hole at each end, these two ends overlapping each other and the stub passing through them.

5. A hose as claimed in claim 1, wherein the ring is a flexible band wound at least once round the hose.

6. A hose as claimed in any of the preceding claims, wherein the ring is superposed over the clamping washer.

7. A hose as claimed in any of the preceding claims 1 to 5, wherein the ring 5 is interposed between the wall of the hose and the clamping washer.

8. A hose as claimed in any of claims 3, 4 or 5, wherein the ring has a flat portion at the point where the stub passes through the ring, said portion having a surface at least equal to that of the clamping washer.

9. A hose as claimed in any of claims 1 to 4, wherein the ring is fixed directly onto the exterior part of the stub and constitutes the means for clamping or retaining the take-off device.

10. A hose having a lateral take-off substantially as hereinbefore described with reference to Figs. 1 and 2, to Figs. 3 and 4, to Figs. 5 and 6, to Figs. 7, 8 and 9, to Fig. 10, to Fig.

1 1, or to Figs. 12,13 and 14 of the accompanying drawings.