GB2058988A - Grommets - Google Patents

Abstract

A grommet is formed of a plurality of similar moulded pieces 2 of rubber or a synthetic plastics material joined to one another by connecting strips 3 and each comprising a segment of a cylinder. The segments 2 can be angularly displaced relative to one another about the connecting strips 3 from positions in which they lie side-by-side in the form of a strip into a configuration in which they form a cylindrical closed body 1. The radial sides 5 of the segments 2 include semi- circular recesses 6 and the adjacent recesses 6 in neighbouring segments 2 in the closed body 1 register with one another together to define cylindrical passages P for receiving cables C. The grommet body 1 is clamped by a housing 10 against a vehicle panel A, and makes a seal with the housing 10, the vehicle panel A and the cables C. <IMAGE>

Description

SPECIFICATION Grommets This invention relates to grommets.

According to the invention there is provided a grommet comprising a plurality of segments joined to one another and so shaped that they can be angularly displaced relative to one another from positions in which the segments lie side-by-side in the form of a strip into a configuration in which the segments form a closed body of which the adjacent faces of neighbouring segments together define passages through the body for receiving cables.

In order that the invention may be well understood there will now be described one embodiment thereof, given by way of example, reference being had to the accompanying drawing, in which: Figure 1 is a view of a grommet body, as moulded; Figure 2 is an end elevation of the same grommet body when closed up to form a plug; Figure 3 is a side elevation of the grommet body depicted in Fig. 2; Figure 4 is an end elevation showing the grommet of Fig. 2 mounted on the panel of a vehicle; and Figure 5 is a section along the line V-V of Fig. 4.

A grommet body 1 comprises a plurality of similar segments 2 moulded in rubber or a synthetic plastics material, suitably a soft, weather resisting, thermo-plastics material. In the present example there are six such segments 2. As moulded, the segments 2 are disposed side-by-side as a strip as shown in Fig. 1, with adjacent segments connected to one another by thin strips 3 which extend the width of the outermost periphery of the body 1.

The segments 2 are preferably substantially identical in shape. Each segment 2 comprises a segment of a circle in cross-section and is of generally triangular configuration with the base of the triangle being curved at 4 to define an arc of that circle. The opposite sides 5 of the generally triangular segment 2 lie along radii of the same circle, and their meeting point 0 defines its centre about which the circle is struck.

Each radial side 5 has formed in it a semicircular recess 6, and the centres of all the recesses in the strip of segments 2 lie on the same pitch circle struck about the centre 0.

The segments 2 can be angularly displaced relative to one another from their strip, opened-out, or developed configuration as shown in Fig. 1, about the thin connecting strips 3 into a closed circular body, i.e. the grommet body 1, as viewed in Fig. 2. When so formed, although not illustrated as such, the adjacent radial sides 5 of adjacent segments 2 will, in face, abut one another and lie radially of the body. Moreover, the semicircular recesses 6 in those adjacent radial sides will register with one another to define cylindrical passages P in which would be positioned cables of circular cross-section, as will now be described.

It should be explained that each segment 2, considered widthwise, is stepped down at each of its opposite end portions 7 from a central cylindrical portion 8, as shown best in Fig. 3. The connecting strips 3 are integral with the outer periphery of the thickened central portion 8. The curved segment bases 4 define the smaller diameter end portions 7, and each segment 2 has an outer curved base 9 of greater diameter struck about the respective centre 0 which together define the central portion 8.

The cables, in fact, would be control cables with a core which translates within a conduit for the purpose of effecting a remote control from an operator to an operated mechanism.

In use, the segments 2 in their opened out form would be wrapped around the individual cables C which would, of course, be positioned in the semi-circular recesses 6, and then the strip of segments would be bent at their connecting strips 3 so that the individual segments are angularly displaced in relation to one another and the strip closed up to form the round body 1. The cables C would be a tight fit within the passages P in the grommet body 1 the resilient material of which would seal around the cable conduits.

The closed-up grommet body 1, with the cables C running through it, would be pushed into a grommet housing 10, which may be a die cast member, the flanged base 11 of which would then be bolted at 1 2 to a support structure, in the present case an apertured access panel A of a vehicle.

The grommet housing 10 has a conical barrel 1 2a extending axially from its flanged base 11 and terminating in a radially inturned lip 1 3. A recess of length 1 is defined by the housing 10 against the panel A whose opposite ends are provided by the panel and the housing lip 1 3 and whose outer periphery is formed by the barrel 1 2a.When the housing 10 is bolted to the panel A, the thickened central portion 8 becomes deformed because its width L is greater than the recess width I and will, therefore, make a tight fit with the access panel and grommet housing to seal thereagainst with its stepped-down end portions 7 extending the one axially outwardly through the aperture in the panel A and the other of the housing lip 13, and the resultant compression of the material of the grommet body deforms the body radially inwards to grip the cables and so make sealing contact therewith.

Any unused cable passages P would be sealed by means of a plug 1 4 which may be a moulding of the same material as the grommet body 1 and which would also be sealingly gripped by the grommet body as its central portion is deformed on bolting.

As will be appreciated, the grommet body need not be round but could be polygonal with the grommet housing formed to suit.

Whilst it is convenient to form the passages P equally in adjacent segments, it would be possible for the recess in one segment to be larger than that of the registering recess in the abutting segment. If cables other than round were to be used, the apertures would be shaped to suit, and in the case of a flat cable, the passages could be entirely formed in one segment side and closed by the abutting, continuous segment side.

The outer periphery 9 of the central segment portion 8 could be tapered to match that of the conical barrel 1 2a of the grommet housing 10.

The design of the grommet body by which it can be moulded as a strip facilitates production as compared with moulding the body in a closed form in addition to which assembly of the grommet body to the cables is simplified by the strip of segments being able to be wrapped around the cables. The segment strip can be made by continuous moulding and then strips of six segments obtained by severing the continuous strip.

The grommet is particularly suited for use with the remote control mechanism described and illustrated in our copending U.K. application No. 24878/77 to seal the entry of the control cables into the cab of the vehicle.

Claims (14)

1. A grommet comprising a plurality of segments joined to one another and so shaped that they can be angularly displaced relative to one another from positions in which the segments lie side-by-side in the form of a strip into a configuration in which the segments form a closed body of which the adjacent faces of neighbouring segments together define passages through the body for receiving cables.

2. A grommet as claimed in claim 1, wherein each segment is of generally triangular shape and the opposite sides of the segment extend radially with respect to the closed body when the segments are angularly displaced into that configuration.

3. A grommet as claimed in claim 2, wherein the closed body is a body of revolution and the third side of the segment is curved, the curved sides forming the outer periphery of said body.

4. A grommet as claimed in claim 2 or claim 3, wherein each of the opposite sides of the segment includes a recess, and the recesses in the adjacent sides of neighbouring segments register with one another to define said passages.

5. A grommet as claimed in claim 4, wherein each recess is semi-circular so that each pair of registering recesses will accept a cable of circular cross-section.

6. A grommet as claimed in any of the preceding claims, wherein the segments are joined to one another by connecting strips about which the segments can be angularly displaced relative to one another.

7. A grommet as claimed in any of the preceding claims, wherein the sides of the neighbouring segments which are adjacent one another when the segments form a closed body abut one another.

8. A grommet as claimed in any of the preceding claims, wherein the individual segments are so shaped that the closed body formed therefrom is stepped-down at each end from a central portion.

9. A grommet as claimed in any of the preceding claims, wherein the joined segments are of rubber or a synthetic plastics material, for example a soft thermoplastics material.

10. A grommet as claimed in any of the preceding claims, wherein the individual segments have been angularly displaced to form the closed body, and said body is mounted in a housing which is secured to a support structure.

11. A grommet as claimed in claim 10, wherein the grommet body seals against the housing and the support structure.

1 2. A grommet as claimed in claim 10 or claim 11, wherein one or more cables extend through the apertured grommet body which makes sealing engagement therewith.

1 3. A grommet as claimed in claim 10 when apendant to claim 8, wherein the central portion of the grommet body has a width in excess of a space, defined between the housing and the support structure, to receive said portion so that the central portion will be compressed when the housing is secured to the support structure to ensure that the grommet body seals against the housing and the support structure.

14. A grommet as claimed in claims 1 2 and 13, wherein the compression of the central portion deforms that portion radially inwardly to grip the cable or cables and so seal thereagainst.

1 5. A grommet as claimed in any of the preceding claims, wherein the segments are substantially identical to one another.

1 6. A grommet as claimed in any of the preceding claims, wherein there are six segments joined to one another.

1 7. A grommet body substantially as herein described with reference to Figs. 1 to 3 of the accompanying drawings.

1 8. A grommet substantially as herein described with reference to Figs. 4 and 5 of the accompanying drawings.