This invention relates to a hose coupling for multi-walled hoses, more particularly those hoses which are sold under the name "BI-WALL".

5 _# In the irrigation and watering -field slow or drip irrigation is becoming very popular, and one form of hose which is utilised for this is a hose of plastics material having along its side a longitudinal pocket, there being small apertures in the wall of the hose _j _0. opening into the pocket, and further apertures opening through the wall of the pocket. In this way the pressure is reduced so that the water then issues from the holes in the wall at a very low rate, or alternatively further outlets, or dripper units can be inserted into the

__ _^ holes in the wall of the pocket.

These forms of hoses are widely used, but one of the problems associated with this form of hose is the joining of the hose by coupling members.

This problem arises in that conventional coupling 20. members do not adequately seal due to the fact that there is a double layer of material along one portion of the hose, so that this does not allow satisfactory sealing of the hose onto the coupling member.

It is an object of this invention to provide a 25. coupling member which is more suitable for the joining and coupling of the particular form of hoses having a separate wall, pocket or chamber along one side of the hose.

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Thus there is provided according the invention a coupling member, the coupling member having a spigot and a ferrule, the spigot having a tapering portion terminating in a lip, and the ferrule also having an 5. inwardly directed lip to engage the lip on the spigot, the ferrule behind the lip having a recessed portion to accommodate the end of the hose.

The spigot is a generally tubular member having at one end a threaded portion on which the ferrule 10. can be screwed, and at the other end having the portion to be attached to the hose.

The end adapted to be coupled to the hose is provided with a nose portion which increases in diameter and terminates In a circumferential lip which faces toward __ _^ the screwed end of the spigot.

The spigot Is then provided with a recessed portion which may be a tapering portion gradually decreasing in diameter by a small taper in order of 2 to 6 degrees to then meet with the end of the threaded portion.

2o. The ferrule is a sleeve open at one end and at the other end having threaded portions adapted to co-operat with the threaded portion on the spigot.

The ferrule at its c-pen end Is provided with an inwardly directed lip adapted to engage against the 25__ outwardly directed lip of the spigot. The ferrule between the lip and the threaded portion is provided with an increase area in diameter, so that there is a relatively large space between the ferrule and the tapered portion. This is to allow room for the end

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of the hose, particularly the portion of the hose having the longitudinal pocket formed thereon.

It is to be noted that the hoses utilising this principle of irrigation are formed from relatively 5. thin plastics material this being in the order of 0.4 millimetres in thickness, but can vary between 0.2 to 0.8 millimetres even up to 1.0 millimetres or more.

Thus it will be seen that the co-operation of the lip on the ferrule engaging on the hose will seal ^* j_0. the hose against the lip on the spigot, the pressure being applied at a small area to thus provide sufficient pressure to seal the hose against the lip on the ferrule, and also to seal the pocket along the side of the hose.

In order to more fully describe the invention ^* ]_5. reference will now be made to the accompanying drawings in which:—

. - FIG. 1 is a cross sectional view of a coupling according to the invention,

FIG. 2 is an enlargement of the portion circled 2o. of the coupling of FIG. 1 in use on a hose,

FIG. 3 is a side view of a second embodiment, the parts being shown in exploded view,

FIG. 4 is a further side view turned 90° from FIG. 3 portion being sectioned,

25. FIG. 5 is a further side view turned 180 ^c from FIG. 3,

FIG. 6 is a further side view turned 270 ^c from FIG. 3, and

FIG. 7 is a view of the coupling member in assembled condition, portion being in section.

The spigot 1 has a ferrule 2 mounted thereon, the ferrule having a threaded portion to engage the 5. threads 3 on the spigot. The threads 3 are a two start thread to give a large lead, and so apply the pincing pressure to the hose.

The lip 4 on the spigot 1 has a face 7 on the side facing the ferrule 2, and similarly the ferrule 10. 2 has its lip 5 with a face 8 which would thus be opposite the face 7 on the spigot.

As shown in FIG. 2 (which is highly enlarged) the hose 6 is thus bent and pinched by the shape of the lip's 4 and 5 and their co-operating shaped surfaces

]_5_ so that the hose is thus actually bent and folded and thus the pinching pressure although it is across the wall of the hose is applied generally longitudinally . _. . of the hose. It is known that when a hose if folded at the walls of the hose collapse and fold toward each

2o. other and thus restrict or even completely stop the flow of liquid through the hose, and this principle Is utilised in the present invention where the wall of the hose is folded so that, the dual passage portion is thus folded with the walls closing toward each other and the final sealing is

25.. done by the lips co-operating to compress the walls together to close off the ^* hose so that there is no leakage through the longitudinal passage on the wall of the hose.

By having a two start thread or a thread with 30. a large lead, the pressure applied to the hose is applied without a great deal of rotational movement between the lips. If a small lead thread is utilised, in order to apply the pressure there would be relatively great

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rotational movement of the lips relative to each other, and this could then cause the lips to cut through the thin walled hose.

By the provision of the recess area between the 5. ferrule and the spigot behind the lips, there is provision for the hose to fit in this area without any constrictions so that the sealing of the hose is by the folding and pinching action of the lips on the hose walls.

Referring to FIGS. 3 to 5, a second embodiment is 10. shown of the invention. The spigot 10 has a co-operating ferrule 11 for attaching to the bi-wall hose, and a clawed ferrule 12 for attaching to a single wall hose to supply the water throught the coupling to the bi-wall hose.

The end of the coupling to connect to the bi-wall 15. hose has an end 13 with a sloping portion 14 leading to the lip 15. Behind lip 15 there is a recess 16 and further sloping portion to a second lip 17 of slightly . - greater diameter than the first lip 15. Behind wall

17 there is a recess 18 formed by portion 19 of lesser 20. diameter of the lip 17, which portion 19 may be parallel or tapered by a small taper of the order of 2° to the cam or threaded portion 20.

The spigot 10 at the cam portion 20 is provided with a cam or thread of large pitch, this being formed 25. with two circumferentially inclined ramps or camming surfaces 21 and 22, each terminating respectively in stop edges 23, 24.

Rearwardly of the cam portion 20 is a connecting portion 25 having a parallel portion 26, an enlarged 0_ tapering portion 27 terminating in a ridge 28. Rearwardly of the region 28 there is a short taper portion 29

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leading to a parallel portion 30 extending to the end 31 for connecting to the supply hose.

The ferrule 11 has at its forward end an inwardly tapered portion 32 leading to a parallel portion 32a 5. forming a lip 32b, this parallel portion 32 being provided with a plurality of fine circular grooves 33. These have a diameter such that the ferrule can be pushed with a frictional fit over the lip 17.

Rearwardly of the parallel portion there is provided 10. the ramp cam operating portion 34, the rearward edge of the ferrule 11 being provided with a circumferentially inclined co-operating surface 35 to co-operate with cam surface 22. Internally of the ferrule 11 there Is provided a co-operating surface 36 to engage the ramp or cam surface

15. 21-

The claw ferrule 12 comprises a body portion 37 having a tapered internal surface 38 to have the same general taper of the portion 27, but of greater diameter so that this portion of the ferrule would freely fit

20. over the rib 28. The ferrule 12 includes three claws 40 extending from the face 39 facing the main body of spigot, each claw 40 having an outer surface as an extension of the outer surface of the ferrule 12, and its inner surface Is an extension of the tapered

25. portion 38, the.claws 40 terminating in a lip 41 so that the ferrule cannot be removed or replaced except by springing of the claws over the rib 28. In use the ferrule 12 is positioned on the spigot portion, the hose is pushed over the enlarged rib 28 up to the

30. shoulder 42 and the ferruloe is then pushed towards the end away from the shoulder 42. On the hose tending to be pulled from the spigot the ferrule is carried

with the hose thus clamping the hose in sealed condition on the spigot.

On attaching the bi-wall hose the ferrule 11 is in position on the spigot 10 with the ferrule 11 screwed 5. to the fully engaged rearward portion. The bi-wall hose is then pushed on over the lips 15-17 to terminate on' the portion 19. The ferrule 11 is then screwed so that the tapered portion 32 engages the bi-wall hose folding it so that it seals against the lip 17. As

10. the ferrule camming or screwing action has a large lead, it quickly engages the hose, and applied the pressure without there being any undue rotational movement of the ferrule on the hose. As noted above these hoses have a very small wall thickness, and thus the folding 5 to close the bi-wall portion and the sealing takes place without undue cutting action of the sealing components .

It will be realised that the invention can be applied • - to hoses other than bi-wall hoses, and can be varied in o. diameter particularly to suit the diameter of the hose being coupled, and that the various angles and dimensions given can be varied without departing from the spirit and scope of the invention.

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