GB2266755A

GB2266755A - Fan-form pleated conduit

Info

Publication number: GB2266755A
Application number: GB9208575A
Authority: GB
Inventors: Ronald Peter Pardy
Original assignee: Ford Motor Co
Current assignee: Ford Motor Co
Priority date: 1992-04-21
Filing date: 1992-04-21
Publication date: 1993-11-10
Also published as: GB9208575D0

Abstract

A pleated conduit for use in the automotive industry provides fan-orm sections (10, 11) between straight sections (12, 13) of the conduit which are provided with fixing points in the form of blind bulbous cavities (14, 15) for accurately locating the conduit on fixing pegs (17) which are attached to the vehicle. The fan-form sections enable the conduit to be stored as a substantially straight conduit. The fan-form may comprise a single pleat (Fig. 4, not shown). The conduit may be vacuum or blow-moulded polyamide and may be of circular or square cross-section. <IMAGE>

Description

Title: Improvements pleated Conduit Field of the Invention The invention relates to pleated conduit particularly the conduit formed by a vacuum or blow moulding process to form a hose, or duct, as used in the automobile industry for conveying liquids or gases.

Background to the Invention It is known to provide a pipe with circumferential pleats which permit the pipe to be readily bent with a flattening of the pleats along the outer radius of the bend and a compression of the pleats along the inner radius. Such pipes are particulary well known as drinking straws in which a bending section is provided to allow the straw to be angled conveniently towards the mouth. In such applications the length of the straw or pipe is not critical.

European Patent Application 0042262 describes a partially pleated sheet of polymeric material exhibiting elastic or plastic memory properties often called heat-recoverable or heat-shrinkable. Such partially pleated sheet material may be used to form a bent pipe which changes on heat treatment to form a pleat-less article having the preformed bend.

It is known to use a blow moulding or vacuum forming technic to produce hose or ducting. The ducting may have a circular, square or other desired cross section.

The present invention seeks to provide a conduit which may be produced and stored in straight sections but which, in use, is flexible at predetermined sections so that it can be bent into a desired profile and secured at predetermined locations.

Summary of the Invention According to the present invention there is provided a pleated conduit having a first fan-form section length interjacent a first and a second right section length.

Preferably the conduit is formed by a blow moulding or vacuum forming process to produce a straight conduit that can subsequently be bent and secured to a vehicle to provide a precisely positioned routing for the flow of liquid or gas. The conduit may have a circular or, preferably, a square section which is more stable and can be more readily shaped to the profiles of a vehicle.

The conduit may be formed from nylon or other suitable plastics material.

The conduit may be fixed in position using blind bulbous cavities which are created during the vacuum forming process and which allow the conduit to be clipped onto corresponding fixing pegs secured to the mounting surface, for example, the chassis or the body work of a vehicle.

Brief Description of the Drawings The invention will now be described by way of example with reference to the accompanying diagrammatic drawing in which:- Figure 1 shows a straight section of tubular pipe vacuum formed with pleats and female fixing means; Figure 2 shows a pleated pipe bent as required in use; Figure 3 shows the fixing means; and Figure 4 shows a box section pleated conduit.

Referring now to the drawings, Figure 1 shows a vacuum formed nylon pipe (1) of circular cross section and having a first fan-form section length (2) interjacent a first and a second straight section of pipe (3) and (4) respectively.

The pipe (1) also contains a second fan-form section length (5) interjacent the second section of straight pipe (4) and a third section of straight pipe (6). A bulbous blind cavity (7) is formed during the vacuum forming process and the adjacent side wall (8) is distended so that the flow of liquid or gas through the pipe is not constricted. The cavity (7) form the female fixing means described in more detail later with reference to figure 3.

The term "fan-form" as used in the specification is defined as one or more pleats tapering from one side of the conduit to the opposite side. It will be appreciated that when a number of such fan-form sections are created in series the conduit will have a predetermined fixed length along one side but a variable length depending upon the depth of the pleat along the opposite side.

An advantage of forming pleated pipes with fan-form sections is that they may be formed by a blow moulding or vacuum forming process as a straight pipe which facilitates storage, but, when required for installation on a vehicle they may be bent into the desired profile with the fixing means accurately located. The accurate fixing locations are provided because the length of one side of the pipe is not extended by the bending process as the pleats fan-out to accommodate the longer path length around the outside of the bend.

Figure 2 illustrates this feature of the invention Referring to Figure 2, a circular section pipe (9) has two fan-form section lengths (10) and (11) between straight sections of pipe (12) and (13) which contain blind fixing cavities (14) and (15) respectively. Although the concertina action of the sections (10) and (11) permit an increase of length of the pipe (9) as measured along the outside radius of the bends the side (16) does not contain any pleated sections so that the linear distance between the fixing cavities (14) and (15) may be sufficiently accurately maintained for the cavities to be aligned with fixing pegs (shown in Figure 3) which are secured to a car chassis at predetermined locations.

Figure 3 shows a male fixing peg (17) located in the female fixing means shown in section III - III shown of Figures 1 and 2. The peg (17) has a flanged head (18) which is sprung into position in the bulbous portion of the blind cavity.

The peg (17) is firmly secured to a vehicle chassis (19).

Referring now to Figure 4 which shows a conduit (20) of square cross section having a number of individual pleats (21) spaced along its length. It will be appreciated that a conduit of square cross section is mechanically more stable than a circular cross section which permits more accurate dimensioning of the pipe length during the vacuum forming or blow moulding production process.

Claims

1. A pleated conduit having a first fan-form section length interjacent a first and second right section length.

2. A pleated conduit as claimed in claim 1 in which the right section length is a hollow tube of circular crosssection.

3. A pleated conduit as claimed in claim 1 in which the right section length is a hollow tube of rectangular crosssection.

4. A pleated conduit as claimed in any preceding claim in which the conduit is formed from nylon.

5. A pleated conduit as claimed in any preceding claim in which the first and/or second section are straight and aligned about a common axis for storage.

6. A pleated conduit as claimed in any preceding claim in which a fixing means is provided on the first and the second right section lengths.

7. A pleated conduit as claimed in claim 6 in which each fixing means is a blind bulbous cavity for attachment to vehicle mounted fixing pegs.

8. A pleated conduit as claimed in any preceding claim which is formed by a blow moulding process.

9. A pleated conduit as claimed in any of claims 1 to 7 which is formed by a vacuum-forming process.

10. A pleated conduit substantially as hereinafter described with reference to the accompanying drawings.