GB2402371A

GB2402371A - Hose assembly

Info

Publication number: GB2402371A
Application number: GB0313037A
Authority: GB
Inventors: Anthony Joy
Original assignee: Dana Automotive Ltd
Current assignee: Dana Automotive Ltd
Priority date: 2003-06-06
Filing date: 2003-06-06
Publication date: 2004-12-08
Anticipated expiration: 2023-06-06
Also published as: GB2402371B; GB0313037D0

Abstract

A hose assembly 10, for a machine which includes an engine, is connected to a fluid reservoir 23 and comprises a fluid cooler 15 including a thin walled metal conduit 24 which is connected to a plastic hose 12. A push fit connection 16 is provided between the hose 12 and the reservoir 23 for use during assembly and maintenance, and a permanent connection 14 is provided between the metal conduit 24 and the plastic hose 12. The push fit connection 16 may comprise a female part (31 see fig 3) which has a spigot (29 see fig 3). The female part (31) is secured to the hose 12, and snap connection is provided by a resilient member (32 see fig 3) which radially extends to fit with a male connector part (34 see fig 3) of the reservoir 23. The assembly 10 may be connected to a vehicle steering system.

Description

240237 1 Title: Hose Assembly

Description of Invention s

This invention relates to a hose assembly and more particularly to a hose assembly for fluid for a machine which includes an engine.

Such hose assemblies typically are provided for returning oil from a power steering system to a reservoir and are thus are intended for use with relatively low pressure fluid. Typically the assembly includes a hose which is formed to a desired three dimensional shape so as to pass around the engine from a low position where oil from an outlet of the power steering system enters the assembly, to a high position where the reservoir is located.

At the low position, the assembly typically includes an oil cooler provided by a heat exchanger through which the oil passes before passing into the hose. The heat exchanger typically is a thin walled metallic e.g. aluminium, tube which may have external fins to promote heat exchange. Where the machine is a vehicle, the oil_cooler typically is provided in an airstream so that passing air as the vehicle moves, flows over the cooler and thus cools the fluid passing therethrough.

The reservoir typically is permanently connected to the hose in a factory environment, and a connection is made during machine assembly, between the hose and the oil cooler. By "permanently" we mean that the connection once made, is not intended subsequently to be disconnected. Typically where the hose is a rubber hose, an external clamp, such as a crimped band, may be fixed around the hose, further to make permanent the connection.

Whereas conventionally the hose has been made of a rubber material, more recently, plastic hoses have been used. r

These have the advantage that the plastic hoses can be formed to a desired Free dimensional configuration subsequent to hose forming, whereas a rubber hose has to be formed to its desired configuration.

It will be appreciated particularly where the machine is a vehicle such as a motor car, making a connection between the oil cooler and the hose on an assembly line, in a low position in the engine compartment, can be difficult, even by working from below the vehicle. To facilitate making a connection, where the hose is made from a rubber material, such connection has been made utilising a push-fit female connector part which has a spigot which is secured in a factory environment to the rubber hose by a clamp, and a resiliently radially outwardly moveable or deformable locking part, and the oil cooler includes a male connector part which has a radially outwardly extending circumferential protuberance which snapinterfits with the locking part to connect the connector and thus the hose, to the oil cooler.

However, use of such a push-fit connector still requires dexterity on the part of the assembly operative in a confined space in the engine compmlent.

Moreover, in a conventional assembly, if it necessary for maintenance purposes to replace the hose, because the hose is permanently connected to the i reservoir, it is necessary to replace the relatively expensive reservoir too. Not only is this costly in terms of componentry, but it is necessary to disconnect the hose and oil cooler at the low position in the engine compartment, and to connect the replacement hose, which is costly and difficult in terms of labour.

-According to a first aspect of the invention we provide a hose assembly for fluid for a machine which includes an engine, and a reservoir for the fluid, the assembly including a plastic hose, and a fluid cooler, which includes a metallic thin-walled conduit, there being a first permanent connection between the plastic tube and the fluid cooler, and a second push-fit, connection between the reservoir and the hose which second connection is made during assembly or maintenance of the machine.

Thus in an assembly in accordance with the invention, an assembly operative is not required to make any connection between the oil cooler and the hose at a low position in an engine compartment, as this connection may be made in a factory environment. However the operative would now be required to make a connection between the hose and the reservoir, but generally there is more room at an upper position in the engine compartment, and certainly the connection between the reservoir and the hose may be made from above the engine, thereby enabling more flexibility in an assembly line.

In the event that the hose ever requires replacement, it is unnecessary to replace the reservoir too, as with a suitable kind of push-fit connection, the push-fit connection between the hose and reservoir may be disconnected relatively straightforwardly. Whereas the oil cooler would require replacement with the hose, making and breaking the connection between the (metal) oil cooler and a (metallic) e.g. power steering system housing, is relatively more straightforward.

The first connection may include at least one, but preferably a plurality of barb formations, over which the plastic hose may be received. It will be appreciated that for a plastic hose, the plastic hose may require stretching, possibly whilst being warmed, to enable the hose to be received over the barb formation or formations. After receiving over the barb or barbs, the hose may be permitted to shrink back towards its original non-stretched shape, thus firmly to grip the barb or barbs ofthe oil cooler.

Whereas these connection steps cannot readily and viably be made in a machine assembly environment, these steps may readily be carried out in a factory environment where the first connection between the hose and oil cooler may be made.

The second connection may be provided by a female push-fit connector part which has a spigot which is permanently secured, e.g. in a factory environment, to the plastic hose, and a resiliently radially outwardly moveable or deformable locking part, which in use, snap-interfits with a radially outwardly extending circumferential protuberance of a male connector part of the reservoir, to connect the female connector part and thus the hose to the reservoir.

In this example, the spigot of the female connector part may include one or more barb formations, and thus the plastic hose may require stretching, possibly whilst being warmed, to enable the hose to be received over the barb formation of formations. Again this may readily be achieved in a factory environment where the hose assembly of the invention is made, so that in the machine assembly environment, the connection between the reservoir and second connector may be a simple push-fit.

For this embodiment of a hose assembly of the invention, it is a requirement that the reservoir is provided with the male connector part with the radially outwardly extending circumferential protuberance. This may require modifying a mould in which the reservoir is currently manufactured.

Thus in a second embodiment of the invention, where the reservoir is adapted for permanent connection with a rubber hose, i.e. the reservoir includes a spigot with one or more barb formations to which the rubber hose in a i conventional arrangement would be connected, usually with there being an external clamp. The reservoir may have permanently connected to it, a short length of rubber hose, and the second connector may include an intermediate connector member which has a spigot which is permanently connected to the short length of rubber hose. The intermediate connector member may further include either: a) a male connector part with a radially outwardly extending circumferential protuberance, for push-fit intermitting, in a machine assembly environment with a resiliently radially outwardly moveable or deformable locking part of a female push-fit connector part which has a spigot which is secured in a factory environment to the plastic hose, or b) a female pushfit connector part which has a resiliently radially outwardly moveable or deformable locking part, which snap interfits in a machine assembly environment with a radially outwardly extending circumferential protuberance of a male connector part which includes a spigot S which is secured in a factory environment to the plastic hose.

According to a second aspect of the invention we provide a method of providing a hose assembly for conveying fluid in a machine which includes an engine, the method including providing a permanent first connection between one end of the plastic tube and a fluid cooler, which includes a metallic thin walled conduit, and providing on another end of the hose, a connector part which enables a second push-fit, connection to be made between a fluid reservoir of the machine and the hose during assembly or maintenance of the machine.

The method may include providing the first connection between the fluid IS cooler and the hose in a factory environment, and providing the push- fit second connection between the hose and the reservoir, in a machine assembly or maintenance environment.

Embodiments of the invention will now be described with reference to the accompanying drawings in which: FIGURE 1 is an illustrative view of a first embodiment of the invention, FIGURE 2 is an enlarged detail of part of the assembly of figure 1, FIGURE 3 is an enlarged detail of another part of the assembly of a figure 1 for a first embodiment, FIGURE 4 is a detail of part of the assembly of figure 1 for a second embodiment.

Referring to figures 1 and 2, there is shown a hose assembly 10 which includes a hose 12, a first connection 14, a fluid cooler 15, and second connection 16.

The hose assembly 10 in use, is located in an engine compartment of a machine such as a motor vehicle, and is mounted to the engine/frame structure components by a plurality of mountings 18, 19 which may be rubber grommets, clips or clamps, which are adapted to be secured to brackets 20.

The hose assembly 10 in use, conveys oil from a power steering system back to a reservoir which is indicated in outline at 23. Thus the assembly 10 conveys relatively low pressure fluid, compared with the pressure of the fluid in use in the power steering system.

To enable the hose 12 to pass around the engine/frame structure components, the hose 12 is formed with a plurality of bends, bl, b2 etc., which give the hose 12 a complex three dimensional shape. The hose 12 is made of a plastic material and thus may be formed to its three dimensional shape subsequent to tube forming.

The assembly 10 further includes an oil cooler IS which in this example includes a metallic thin-walled conduit 24, having a diameter about twice that of the hose 12, thus providing a large surface area for cooling fluid passing through the oil cooler 15.

The conduit 24 may for example be made of aluminium, and if desired may have external fins to promote oil cooling. The conduit 24, is preferably located in an air stream so that passing air flows over the oil cooler 15 to enhance cooling. Additionally, the oil cooler 15 includes an integral metallic tube 24_ which itself is of complex configuration, and is connected to the hose 11, and a further integral metallic tube 24_ which again is of complex configuration and is adapted to be secured to the power steering system, or another machine part, and sealed thereto, for example by a compression ring 37.

Referring to figure 2, the oil coola 15, or rather the tube 24_ of the cooler 13, is connected to an end 27 of the hose 12 by the first connection 14 which is provided by a plurality of barbs 25, three in this example, formed on the external surface of a spigot 26 being the end of the thin-walled tube 24a.

The spigot 26 and barbs 25 are received within the hose end 27 as illustrated in figure 2, to form a permanent connection between the hose 12 and the oil cooler 22. This is achieved in a factory environment, by stretching the internal diameter of the tube 12 at the hose end 27, with a former or mandrel, possibly whilst applying gentle heat to the plastic hose end 27, and then pushing the spigot 26 and barbs 25 into the hose end 27. The plastic by its nature, will slowly return to towards its originally formed diameter, thus gripping the Spigot 26 and barbs 25. In actuality, the plastic will shrink back around the barbs 25 so closely that the hose 12 cannot subsequently, after a short time, be pulled off the spigot 26. Thus the hose 12 to oil coola 15 first connection 14 is permanent.

Referring to figure 3, at the opposite end 28 of the hose 12, the second connection 16 is provided. In a first embodiment, the second connection 16 has a female connector part 31, which is integral with a spigot 29 with barbs 30 to enable the female connector part 31 to be secured to the hose end 28 in a similar manner to that which the oil cooler spigot 26 with barbs 25, is secured to the first hose end 27, and in a factory environment.

The female connector part 31 teas a resiliently radially outwardly moveable or deformable locking part 32, which in use, snap-interfits with a radially outwardly extending circumferential protuberance 33 of a male connector part 34 of the reservoir 20 to form the second connection 16 and thus to connect the hose 12 to the reservoir 20 in a push-fit manner.

The male connector part 34 and protuberance 33 of the reservoir 20 is in this example integrally formed with the remainder of the reservoir 20 and thus the reservoir needs to be particularly formed to be compatible with the hose assembly 10 in this example, but in the second embodiment described below with reference to figure 4, the hose assembly 10 may be used with an existing reservoir 20 construction.

In each case though, upon machine assembly, there is no requirement to make a connection between the hose 12 and the oil cooler 15 as a permanent connection has already been made in a factory environment. Simply, by virtue of the push-fit connection 16 achievable between the reservoir 20 and the hose 12, an assembly operative only needs to make a connection between the reservoir 20 and the hose 12 where typically, there is more space in the engine compartment for such connection to be relatively easily made.

Of course, the operative would still have to make connection between the oil cooler 15, or at least the further tube 24b thereof and a housing of a power steering system or other engine part, but such metal-to-metal connection generally is straightforwardly made, for example using the compression ring 37 and a lock nut (not shown) which is rotated to connect the oil cooler 15 to the housing, whilst deforming the compression ring 37 therebetween to form a seal.

Preferably the second connection 16 between the reservoir 20 and the hose 12, is of the kind which can be released subsequent to assembly, for example by either exerting a substantial axial force between the hose 12 and reservoir 20 to force the locking part 32 back over the circumferential protuberance 33, or by using a suitable tool to move the locking part 32 radially i outwardly to enable the female connector 31 to be moved axially of the spigot 34 away from the reservoir 20.

In each case, in the event that the hose 12 requires replacement in service, the hose 12 (and oil cooler 15) can be replaced separately from the more expensive, reservoir 20.

In figure 4, an alternative embodiment is shown in which parts the same as or similar to those described with reference to figure 1 are indicated by the same reference numerals.

In this example, the hose assembly 10 is intended for use with a reservoir which, instead of having a spigot 34 with a radially outwardly extending protuberance 33 to connect with a push-fit to a female connector part 31 of the second connection 16, the reservoir 20 includes a spigot 39 with one or more barbs 40. Such a reservoir 20 may be produced for use for connecting to a rubber hose 41, with the aid of an external clamp 38 or the like.

In this embodiment, a small length of rubber hose 41 is connected to the reservoir 20 by the spigot 39 and barbs 40. The plastic hose 12 is then connected to the rubber hose 41 by an intermediate connector member 45 which is connected to the rubber hose 41. In this example the intermediate connector member 45 includes a spigot and barbs by which the intermediate connector member 45 is connected to the short length of rubber hose 41, again with the aid of an external clamp (not shown) as necessary. Such connection of the rubber hose 41 to the reservoir 20 and to the intermediate connector member 45 is achieved in a factory environment The intermediate connector member 45 includes a male connector part 47 with a radially outwardly extending circumferential protuberance 48, and the plastic hose 12 is connected to a female connector part which may be substantially identical to the female connector part shown at 31 in figure 3.

Thus in a machine assembly environment, the second connection 16 between the hose assembly 10 of the invention and the reservoir 20 may simply be made by push-fitting the female connector part 31 on to the male connector part 47 of the intermediate connector member 45.

As an alternative to the embodiment of figures 4, if desired the intermediate connector member 45 may include a female connector part with a radially inwardly resiliently deformable or moveable locking part, in which case the connector part connected to the plastic hose 12 end, may be a male connector part with a radially outwardly extending protuberance.

Various modifications may be made without departing from the scope of the invention.

For example, although the invention has been described in relation to a hose assembly for returning power steering system oil to a reservoir, the invention may be applied to other hose assemblies of machines win engines, where there is a cooler for cooling fluid to which a hose needs to be connected.

In each embodiment described, the hose assembly 10 of hose 12 and cooler 15 are not provided in a machine assembly environment, and by virtue of the invention, assembly into the machine is considerably facilitated.

The features disclosed in the foregoing description, or the following claims, or the accompanying drawings, expressed in their specific forms or in terms of a means for performing the disclosed function, or a method or process for attaining the disclosed result, as appropriate, may, separately, or in any combination of such features, be utilised for realising the invention in diverse forms thereof.

Claims

1. A hose assembly for fluid for a machine which includes an engine, and a reservoir for the fluid, the assembly including a plastic hose, and a fluid cooler, which includes a metallic thin-walled conduit, there being a first permanent connection between the plastic tube and the fluid cooler, and a second, push-fit, connection between the reservoir and the hose which second connection is made during assembly or maintenance of the machine. (

2. An assembly according to claim 1 wherein the first connection between the oil cooler and the hose is made in a factory environment.

3. An assembly according to claim 1 or claim 2 wherein the first connection includes at least one barb formation, over which the plastic hose is received.

4. An assembly according to any one of the preceding claims wherein the second connection is provided by a female push-fit connector part which has a spigot which is permanently secured to the plastic hose, and a resiliently radially outwardly moveable or deformable locking part, which in use, snap- interfits with a radially outwardly extending circumferential protuberance of a male connector part of the reservoir, to connect the female connector part and thus the hose, to the reservoir.

5. An assembly according to claim 4 wherein the spigot of the female connector part includes one or more barb formations over which the hose is received.

6. An assembly according to any one of claims 1 to 3 wherein the reservoir is adapted for permanent connection with a rubber hose.

7. An assembly according to claim 6 wherein the second connection includes an intermediate connector member which has a spigot which is permanently connected to a short length of rubber hose which in use is connected to the reservoir, the intermediate connector member including either: a) a male connector part with a radially outwardly extending circumferential protuberance, for push-fit interfitting, with a resiliently radially outwardly moveable or deformable locking part of a female push-fit connector part which has a spigot which is secured to the plastic hose; or À b) a female push-fit connector part which has a resiliently radially outwardly moveable or deformable locking part, which snap interfile with a IS radially outwardly extending circumferential protuberance of a male connector part which includes a spigot which is secured to the plastic hose.

8- A hose assembly substantially as hereinbefore described with reference ! to and/or as shown in the accompanying drawings.

9. A method of providing a hose assembly for conveying fluid in a machine which includes an engine, the method including providing a permanent connection between one end of the plastic tube and a fluid cooler, which includes a metallic thin walled conduit, and providing on another end of the hose, a connector part which enables a second push-fit, connection to be made between a fluid reservoir of the machine and the hose during assembly or maintenance of the machine.

10. A method according to claim 9 which includes providing the first connection between the fluid cooler and the hose in a factory environment, and providing the connector part in a factory environment, and providing the push- fit second connection between the hose and the reservoir, in a machine assembly or maintenance environment.

11. A method of providing a hose assembly substantially as hereinbefore described with reference to the accompanying drawings. (

12. Any novel feature or novel combination of features described herein and/or shown in the accompanying drawings. (