This invention relates to a hose assembly comprising a reinforced hose and an end fitting of the kind comprising an insert and a ferrule between which an end of the hose is secured. It relates also to a series of said hose assemblies and end fittings of different bore sizes, to a method of forming a hose asseπbly of said kind, an end fitting for said assembly and a component part for said end fitting.

In the hydraulics industry hoses typically incorporate a layer of wire reinforcement sandwiched between a rubber liner and a cover.

The hoses typically are terminated with end fittings which achieve an anchorage by disturbing the lie of wire reinforcement _/ and so compressing the rubber liner underneath the di turbed part of the wire reinforcement. This provides a termination which is satisfactory for many purposes but the flexibility and deformability of the rubber liner restricts the maximum axial load that can be carried fay the end fitting.

To obtain a higher axial load strength a greater anchorage effect is achieved by cutting back the rubber liner, in addition to any cover which may surround the wire reinforcement, and using an insert having a greater outer diameter. The conventional teeth on the larger type insert provide an enhanced interlock by direct wire entrapment. There is direct contact with the wire reinforceπeπt by teeth on the insert and ferrule in contrast to the intervening presence of the rubber liner when anchorage is achieved without cutting back the rubber liner.

Because of the option of cutting back the rubber liner it is necessary for πaπufacturers to provide two ranges of different types of insert for use with a single range of different bore size hoses. This adds undesirably to the m-mufacturer's costs, includ g the cost of πaiitaining adequate stock levels.

The need for two ranges of different types of insert could be avoided hy cutting back the rubber liner in all cases, but as yet this operation is time consuming and so adds to the manufacturer's cost.

An object of the present invention is to provide a hose asseπbly, an end fitting, a series of hose assemblies and of end fittings and a component part of said end fitting whereby a good anchorage may be achieved together with a reduction of costs.

According to one aspect of the present invention a hose end fitting comprises an insert, a ferrule to surround said insert and adapted to be axially located relative to the insert and an adaptor locatable on the insert in use to lie between and occupy a part of the radial space between the insert and ferrule.

The adaptor preferably is in the form of a ring and preferably has a radial thickness substanti lly equal to the radial thickness of the liner layer of a hose to which the end fitting is intended to be attached.

The outer diameter of the adaptor is to be less than the inner diameter of the main part of the length of the ferrule. Preferably it is less by at least twice the thickness of the hose wire reinforcement.

The present invention further provides for use in a hose end fitting an adaptor cccprising a ring of material, a first part of the ring being adapted to seat around a hose insert and be substanti lly nαn-defoπnable and a second part normally to lie radially spaced from a hose insert and to bs radially defoπnable in a direction towards the insert.

Preferably said first part of the ring is comprised by two axially spaced substantially non-deformable portions interconnected fay said radially defoπnable second part. One of the two portions may present a substantially planar end face which lies in a plane substantially perpendicular to the major axis of the adaptor ring. Another of the two portions may present an end face of a substantially f_rusto- onical shape. The two axially spaced portions and the interconnecting second part may be shaped to define an

inwardly facing groove. The interconnecting second part preferably has a radial thickness in the range 15% to 75%, more preferably in the range 20% to 50%, of the radial thickness(es) of the first part.

It is envisaged that the interconnecting second part may have a thickness less than 40% of the radial thickness(es) of the first part. That percentage thickness may be no more than 25%.

According to another aspect the invention provides an end fitting and a hose assembly, a series of end fittings and a series of hose assemblies which incrarporate(s) an adaptor as hereindescrJbed and wherein the number of different sizes of each of the ferrules, inserts and adaptors in the series corresponds with the number of different sizes of hose with which they may be assembled.

A defoπnable part of an adaptor ring may be arranged, in use, to lie in an end fitting substantially axially aligned with a radially inwardly extending formation, such as a saw-tooth like ci cum ereπtial1y extending rib, provided within a ferrule to engage the exposed reinforcement at the end of a hose.

The insert may have a shoulder against which the adaptor may abut for relative axial location. The shoulder may be defined fay a rib which separates a part of the insert which in use actually extends within a hose from an end part that lies outwards of the end of the hose. That rib may define a side of a location groove axially alignable with an inwardly extending ferrule flange in known manner as illustrated for example in British Patent Specification No. 2091832A. Upon swaging of the ferrule to coπpress the end of the hose about the insert the ferrule flange will enter the location groove so as to inhibit subsequent axial, separation of the insert and ferrule.

The insert may have hose locating formations such as saw tooth section ribs over the whole of its length for location in the end of a hose. The griqpt-nr may be dimensioned axially so that when one axial end abuts an abutment on the insert the other end is substantially aligned with one of

the locating formations on the insert. Subsequent swaging of the ferrule to cαnpress the hose against the adaptor and insert may be arranged slightly to compress radially inwards the substantially non-deformable part of the adaptor. It will then be mechanically interlocked with said one of the hose locating formations.

As an alternative to compression of the ferrule causing a mechanical interlock of the adaptor with the insert, the adaptor may be interlocked by direct compression prior to assembly of the insert with a hose or ferrule. In further alternatives other means such screw threads on the adaptor and insert or other techniques such as non-mechanical ύiterconnection for example by brazing or adhesives may be employed to achieve relative axial location.

The invention further provides a hose assembly cαnprising a reinforced hose having secured thereto an end fitting in accordance with the present invention. Said assembly may incorporate an adaptor of a kind as hereindescribed and which is in a deformed condition.

The hose of the assembly may have a liner and/or a cover layer at least one of which does not extend fully into the end fitting. The hose may have a cover which extends substanti lly fully into the end fitting. The hose may have a reinforcemeπt of wire braid; the wire braid nay have a cover which may extend substantially fully into the end fitting and which may be thinner than a liner layer of the hose.

An embodiment of the present invention will now be described by way of example, with reference to the accompanying drawings wherein;-

Figure 1 is a longitudinal section of an end of a hose assembly of the invention at an intermediate stage of manufacture;

Figure 2 is a longitudinal section of the adaptor of the Figure 1 assembly;

Figure 3 is a detail view of the adaptor of Figure 2 in situ on part of the insert of Figure 1, and

Figure 4 is a longitudinal section of the assembly shown in Figure 1 after swaging of the ferrule.

The hose assembly 1 as illustrated in Figure 1 comprises an insert 2, a ferrule 3, an adaptor 4 and a wire reinforced hose 5 only an end part of which is shewn.

The insert has a tail portion 2a and stem portion 2f for insertion into an end portion 5a of the hose and first and second axially spaced radially outwardly directed annular abutments 2b and 2c respectively on that portion 2d which in use lies beyond the end of the hose.

The abutment 2c is defined by a face of a circuinfereπti lly extending rib 6. The abutment 2b is defined by a face of a groove 2e which lies between the insert outer region and the rib 6.

The abutment 2b has a larger outer diameter than the abutment 2c. The ferrule 3 for securing to the insert has an inwardly directed annular projection 3a which, prior to swaging, has an inner diameter intermediate the outer diameters of the abutments 2b and 2c.

The external surface of the insert stem portion 2f and the inner surface of the ferrule each have annular ribs 8 of a saw-tooth shape in cross—section _*

The hose 5 has a wire reinforcement layer 9, an outer cover 10 and an inner liner 11. The inner diameter of the ferrule ribs prior to swaging corresponds with the outer diameter of the wire reinforcement 9 which is exposed fay cart-ting back the cover 10 for a length substantially equal to the distance which the hose extends into the ferrule.

The outer diameter of the insert ribs corresponds to the inner diameter of the liner 11.

The adaptor 4 is dimensioned to fit around the insert stem portion 2f to lie adjacent the abutment 2c and axially space the hose liner 11 from that abutment face. It has a radial thickness equal to the thickness of the liner. The liner is cut back a distance corresponding to the axial length of the ada -oτ- so that the wire reinforcement layer 9 extends over the adaptor, between the radially outer face of the adaptor and the surrounding ferrule.

The construction of the adaptor 4 is shown in detail in Figure 2. It comprises two axially spaced and substantially non-deformable portions 12 interconnected at their radially outer regions by a relatively deformable web part 13 such that the adaptor defines a radially inward facing groove 14. In this example the web part has a radial thickness which is approximately 25% of that of the non-deformable portions (12).

One adaptor end 15 is flat to abut directly against the insert abutment face 2c. The other end face 16 is of a frusto-conical shape angled so as to face radially outwards. The angled feature has a purpose described later.

The aforedescribed ferrule ribs 8 are positioned axially relative to the ferrule, and thus in the assembly relative to the face 2c, so that a first rib 8c lies axially aligned with the deformable web 13 of the adaptor.

As an initi l step in forming the hose assembly the adaptor is fitted to the insert to abut the abutment 2c and then crimped lightly so that it is retained on the insert, preferably fconing a mechanical interlock with a nipple rib 8c as shown in Figure 3.

The ferrule and the cut back hose end are then fitted around the insert to form an intermediate assembly as shown in Figure 1. The ferrule is then radially compressed for example by pallet swaging so that the ferrule projection 8c enters the insert groove 2e to give axial location of the ferrule relative to the insert. At the same time the ferrule ribs 8 εct on the exposed wire reinforcement layer to disturb the lie of the wire where it surrounds the hose liner and to form a mechanical type interlock by

direct wire entrapment where the wire extends over the adaptor. The wire entrapment arises because the first ferrule rib 8c inwardly deforms the wεb part 13 of the adaptor and causes the interposed wire to lie against that deformed web.

The resulting configuration and deformed shape of the adaptor are shown in Figure 4. This is a schematic view and in practice the spaces 20 in crevice regions adjacent the saw-tooth edges will not be vacant as shown but will be occupied by deformed wire reύtforσement or any cover material 10 not fully removed during initial preparation of the hose end.

The inclined end face 16 of the adaptor 4 in conjunction with a substantially square cut end of the hose liner provides a small annular space which assists acccπrnodation of excess liner materi l which may be present in consequence of irregularities arising when cutting back the liner.

The resulting deformation of the adaptor as above described leads to good axial retention of the wire reinforcement. This is achieved without the need to use specialised inserts. If a high strength of axial retention is not required the adaptor can simply be emitted, the hose liner not being cut back. In that case the wire reinforcement will be caused to adopt the so called "disturbed lay" over the whole of its length within the ferrule.