Hose assembly for an engine air intake system

Abstract

A hose assembly 20 for engine intake air comprises a hose 22 having connection regions 22a, 22b at first and second ends of the hose and an axially compressible and extendable bellows region 22c disposed between the two connection regions. In the invention, an inextensible inner tube 24 is disposed within the hose 22 which has a gas-impermeable wall. The inner tube 24 has first and second ends 24a, 24b that seal, respectively, against the first and second connection regions 22a, 22b of the hose when the bellows region is compressed. At least one of the first and second ends of the inner tube 24a separates from the adjacent connection region 22a of the hose 22 when the bellows region 22c is extended.

Claims

1. A hose assembly for engine intake air, comprising an outer hose having first and second ends that serve as connection regions and an axially compressible and extendable bellows region disposed between the two connection regions wherein an inextensible inner tube is disposed within the outer hose and having a gas-impermeable wall, wherein the inner tube has first and second ends that seal, respectively, against the first and second connection regions of the outer hose when the bellows region is compressed, and wherein at least one of the first and second ends of the inner tube is spaced from the adjacent connection region of the outer hose when the bellows region is extended.

2. A hose assembly as claimed in claim 1, wherein both the outer hose and the inner tube are flexible.

3. A hose assembly as claimed in claim 2, wherein the outer hose and the inner tube are made of an elastomeric material.

4. A hose assembly as claimed in claim 1, wherein external clamping rings are arranged in valleys defined by folds of the bellows region of the outer hose and act to compress the bellows region against the inner tube.

5. A hose assembly as claimed in claim 1, wherein the inner diameter of at least one of the connection regions of the outer hose is equal to the inner diameter of the inner tube.

6. A hose assembly as claimed in claim 1, wherein the inner diameter of one end of the outer hose is equal to the outer diameter of an adjacent end of the inner tube and is operative to receive and seal against the adjacent end of the inner tube.

7. A hose assembly as claimed in claim 1, wherein the end of the inner tube that is spaced from the adjacent connection region of the outer hose when the bellows region is extended has a tapering outer wall.

8. A hose assembly as claimed in claim 6, wherein the end of the inner tube that is spaced from the adjacent connection region of the outer hose when the bellows region is extended of the inner tube is formed with axially extending slots.

9. A hose assembly as claimed in claim 1, wherein the end of the inner tube that is spaced from the adjacent connection region of the outer hose when the bellows region is extended is formed with a radially inwardly projecting round rib.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The invention will now be described further, by way of example, with reference to the accompanying drawings, in which:

(2) FIG. 1, as earlier described, shows a charge air cooler movably mounted on a radiator,

(3) FIG. 2 is a section through a hose assembly of the invention in the compressed state adopted in the operating position of the CAC,

(4) FIG. 3 is a section through the hose assembly of FIG. 2 in the extended state that it adopts in the cleaning position of the CAC, and

(5) FIG. 4 is a section similar to that of FIG. 4 showing an alternative embodiment of the invention.

DETAILED DESCRIPTION OF THE EMBODIMENT

(6) FIGS. 2 and 3, show a hose assembly 20 composed of an outer hose 22 and an inner tube 24, both made of an elastomeric material. The outer hose 22 has a connection region 22a to be secured to the inlet 16 or the outlet 18 of the CAC 10, for example by means of a jubilee clip (not shown) and an end region 22b to be connected in a similar manner to a pipe leading to a turbocharger or to an engine intake manifold. The region 22c between the two end connection regions 22a and 22b is constructed as a bellows with multiple annular folds that allow it to be extended and compressed.

(7) The inner tube 24, which has a gas-impermeable wall, has a central region 24c, of increased wall thickness and enlarged outer diameter, disposed with the bellows region 22c of the outer hose 22, an end region 24b retained within the end region 22b of the outer hose 22 and an end region 24a that is tapered to effect a hydrodynamic seal against the connecting region 22a of the outer hose 22.

(8) Springs or clamping wires 26 are fitted within the valleys defined by the folds of the bellows region 22c to strengthen the outer hose 22 and compress the bellows radially against the outer surface of the inner tube 24.

(9) In the operating position of the CAC 10, the hose assembly 20 adopts the position shown in FIG. 2. Air that has been compressed by a turbocharger enters the inner tube 24 from the right, as viewed, and flows through the interior of the inner tube 24. As the latter has smooth walls, it creates no turbulence and the air flow therefore meets with minimal flow resistance. On reaching the opposite end of the hose assembly, the air transitions smoothly from the inner tube 24 to the connection region 22a of the outer hose 22.

(10) As the tapered end 24a of the inner tube 22 and the connecting region 22a of the outer hose 22 are pushed against one another, the end of the inner tube 24 is compressed radially. Axially extending slots 24d in the end of the tube enable its diameter to be reduced under the action of the mating tapering surfaces. This creates an effective hydrodynamic seal that minimises air resistance. After initial equalization of the pressures on opposite sides of the inner tube 24, there is be no air movement through the slots 24d to create turbulence in the through flow of the compressed air.

(11) The position of the hose assembly shown in FIG. 3 is that adopted when the assembly is extended to accommodate movement of the CAC 10 to the cleaning position. Despite allowing the movement of the CAC, neither of the connection regions of the outer hose 22 needs to be separated from the pipe to which it is secured. Within the hose assembly, extension of the bellows region 22c causes the end 24a of the inner tube 24 to separate from the connection region 22a of the outer hose 22. Though this disturbs streamline flow through the hose assembly 20, this is unimportant because no air flows through the CAC while a cleaning operation is being performed.

(12) Though the inner tube 24 has been described as being retained at one end within the connection region 22b of the outer hose, this is not essential as the inner tube 24 could float within the outer hose 22 and effect a seal with the outer hose 22 at both its ends, in the manner described for the end 24a, only when the hose assembly 20 is compressed.

(13) The hose assembly 20 in FIGS. 2 and 3 may be connected either to the inlet 16 or the outlet 18 of the CAC. As the internal diameter of the hose assembly is substantially uniform over the entire length of the hose assembly, the direction of air flow, and the orientation of the hose assembly, are not critical.

(14) The embodiment of the invention shown in FIG. 4 differs from that of FIGS. 2 and 3 in details of the construction of the outer hose 122 and the inner tube 124. Whereas in the embodiment of FIGS. 2 and 3, the tapering outer wall of the inner tube 24 contacts the tapering inner wall of the outer hose 22 to effect a seal, in the embodiment of FIG. 4, it is the axial end surface of the inner tube 124 that contacts the outer hose 122 to effect a seal. The outer hose 122 in this case has a clamping ring 126 at the junction between bellows region and the connection region shown on the left in the drawing. The adjacent end of the inner tube 124 no longer has axial slots and its outer surface is not tapered. Instead, the inner tube 124 has an inwardly projecting rounded annular rib 124a that increases the rigidity of the end of the inner tube 124.

(15) Though the described hose assembly has been described by reference to its application in an engine intake system having a movable component, it will be appreciated that it is not restricted in its use to this application. The invention instead may find use in any application requiring an extendable hose where it is desirable to reduce resistance to flow and an excessive pressure drop across the hose.