GB2177771A

GB2177771A - A conduit fitting

Info

Publication number: GB2177771A
Application number: GB08616332A
Authority: GB
Inventors: Robert Daniel Bopp; Jr Stewart Lee Clark
Original assignee: Acco Babcock Inc
Current assignee: FKI Industries Inc
Priority date: 1985-07-08
Filing date: 1986-07-04
Publication date: 1987-01-28
Also published as: FR2584476A1; JPS6224018A; IT8648240A0

Abstract

A conduit fitting for anchoring a conduit assembly (122) to a support (40). The conduit fitting including two principal components: a cylindrical body (21) with an exterior flange (26), and a clip member (32) having a plurality of divergent spring fingers (38). The clip member (32) is located on a portion (24) of the body (21) by a bead projecting from a deformed circumferential region of the portion (24) of the body (21). The clip member (32) having a front edge (34) in abutting engagement with the flange (26) and free ends of the divergent fingers (38) defining a gap with the front edge (34) equal in size to a predetermined thickness of the support (40). In use the free ends of the fingers contact against a face (43) of the support (40) to anchor the conduit fitting to the support (40) and a conduit assembly (122) is attached to the body <IMAGE>

Description

SPECIFICATION A conduit fitting This invention relates to a conduit fitting for use in anchoring a conduit assembly, and more especially to a conduit assembly including an automobile brake or speedometer control cable, which is anchored to a support structure such as an automobile dashboard.

According to the invention there is provided a conduit fitting for anchoring a conduit assembly to a support of predetermined thickness, the conduit fitting including a body having a first portion containing a first bore for receiving the conduit assembly, a second portion for insertion through an aperture in the support, the second portion containing a second bore communicating with the first bore, an exterior flange for abutting against the support to limit the insertion of the second portion of the body into the aperture and a clip member located on the second portion of the body by a bead projecting from a deformed circumferential region of the first portion of the body, the clip member having a first end in abutting engagement with the flange and a second end extending away therefrom, and a plurality of resilient fingers diverging radially outwardly toward the first end, the plurality of fingers having free ends spaced a predetermined distance from the first end, the predetermined distance being equal to the predetermined thickness of the support.

Embodiments of the invention will now be described by way of example with reference to the accompanying partly diagrammatic drawings in which: Figure 1 is a cross sectional view of a first embodiment of a conduit fitting according to the invention shown mounted on a support wall with a sectional plane passing through fingers of the first embodiment; Figure 2 is a cross-sectional view of a second embodiment of the conduit fitting with a rubber seal for use therewith, the sectional plane passing through fingers of the second embodiment; Figure 3 is a cross-sectional view of a third embodiment of the conduit fitting with a return spring for use therewith the sectional plane passing through fingers of the third embodiment; Figure 4 illustrates an example of a conduit assembly shown broken away in layers for use with the conduit fittings shown in Figures 1, 2, 3;; Figure 5 illustrates another example of a conduit assembly shown broken away in layers for use with the conduit fittings shown in Figures 1,2, and 3; Figure 6 illustrates a further example of a conduit assembly shown broken away in layers for use with the conduit fitting shown in Figures 1,2, and 3; Figure 7 is a part sectioned exploded view of an assembly apparatus for securing a clip member onto a body of the conduit fitting shown in Figures 1 and 2; Figure 8 is a part sectioned exploded view of an assembly apparatus for securing a clip member onto a body of the conduit fitting shown in Figure 3; Figure 9 illustrates a blank for use in forming the clip member of the conduit fittings shown in Figures 1, 2 and 3; Figure 10 shows the blank of Figure 9 after it has been formed into a cylindrical shape; and Figure 11 is a cross sectional view of an assembled conduit fitting and conduit assembly.

With reference to Figure 1, a first embodiment of the conduit fitting includes a cylindrical body 21 constructed from deformable metal, having a conduit receiving rearward portion 22 and a clip receiving forward portion 24. Centrally located on the body 21 intermediate the portions 22, 24 is a circumferential flange 26. A relatively large conduit bore 28, co-axially penetrates the conduit receiving rearward portion 22. The bore 28 communicates with a relatively narrower bore 30 which penetrates the clip receiving forward portion 24. The bore 30 is counter sunk from an initally pianar forward face 25 of the portion 24 remote from the bore 28.

A spring clip member 32 made of metal is mounted on the clip receiving forward portion 24 of the body 21 with an edge 34 abutting against the flange 26, and three spring fingers 38 connected at an edge 36 of the member 32 diverge away from the edge 36 with their free ends towards the flange 26. The free ends of the fingers 38 are spaced from the flange 26 to define a gap having an axial dimension corresponding to the distance between the edge 34 and the free ends of the fingers 38. This distance is equal to the thickness of a support wall 40, shown in dotted outline, to which the fitting is to be mounted.

The conduit fitting is mounted on the support wall 40 by inserting the clip receiving forward portion 24 into an aperture 42 in the support wall 40. As the forward portion 24 is inserted further the spring fingers 38 are compressed radially inwardly towards the body 21 by contact with the sides of the aperture 42, allowing the clip receiving forward portion 24 to pass. Yet further insertion causes the fingers 38 to pass through the aperture 42 so that the free end of the fingers 38 snap back radially outwardly as the flange 26 abuts against a first face 41 of the support wall 40, the free ends of the fingers 38 contacting against a second face 43 of the support wall 40 to anchor the conduit fitting.

The spring clip member 32 as shown in Figures 9 and 10 is constructed by stamping a rectangular metal blank having the edge 34 as one side and the edge 36 as an opposite side. The fingers 38 are formed by a stamping operation in which parts of the blank between the edges 34 and 36 are cut out to leave rectangular fingers 38 connected to the blank adjacent the edge 36 and free adjacent the edge 34. The blank is then formed into a cylindrical shape and the free ends of the fingers bent radially outwardly. The resultant cylindical shape of the member 32 having a smaller diameter than the clip receiving forward portion 24 so as to ensure a tight fit on the forward portion 24.

The conduit fitting is assembled by firstly opening the cylindrical shape of the member 32 by inserting a beveled punch having the same diameter as the clip receiving forward portion 24 into the member 32, the member 32 is then stripped off the punch by stripping means co-axial with the punch and transferred onto the conduit fitting so that the edge 34 abuts against the flange 26.

Then, with reference to Figure 7, the spring clip member 32 is secured to the clip receiving forward portion 24 by an assembly procedure using an assembly apparatus in which the conduit receiving rearward portion 22 is located in a seat 50 of the assembly apparatus the seat 50 having first and second bores 52, 54 sized to receive the rearward portion 22 and the flange 26 respectively. The assembly apparatus also includes a locating member 56 having a punch 58 co-axially and slidably positioned within a sizing bore 61 of a sizing ring portion 60 the sizing bore 61 having an internal diameter substantially the same as the external diameter of the cylindrical shaped spring clip member 32.The sizing bore 61 communicates with a spacing bore 63 of a spacing ring portion 62 the spacing bore 63 having an internal diameter sufficiently large enough to completely enclose the spring fingers 38 with relatively little deflection of the fingers 38.

The locating member 56 is then moved towards the conduit fitting, accommodated in the seat 50, until a leading face 65 of the spacing ring portion 62 abuts against a face 5 1 of the seat 50. In this position the sizing bore 61 of the sizing ring portion 60 closely surrounds the edge 34 of the clip member 32 and the fingers 38, the fingers 38 being deflected radially inwardly by walls of the sizing bore 61. The punch 58 is then moved towards the planar forward face 25 of the clip receiving forward portion 24 and into contact therewith. A central circular boss 64 on a leading face 59 of the punch 58 serves to centre the punch 58 by mating with the counter sunk portion 44 of the bore 30. The leading face 59 of the punch 58 is also provided with an inner peripheral ridge 66 and an outer peripheral ridge 68.When the punch is struck the ridge 66 cuts a groove 70 in an outer region of the pianar forward face 25 thereby deforming the face 25 by forcing some of the metal to fiow radially outwardly over the edge 36 of the spring clip member 32. The metal flow forms a bead which secures the spring clip member 32 to the clip receiving portion 24 without affecting the position of the edge 34 against the flange 26 or the gap between the free end of the fingers 38 and the edge 34. The outer edge 68 shapes the flowed metal to intersect smoothly with the edge 36 as seen at 72.

A second embodiment is shown in Figure 2 in which a conduit fitting includes the cylindrical body 21 and the spring clip member 32 described in relation to the first embodiment together with a seal bore 80 located intermediate the bore 28 and the bore 30 and communicating with each of the bores 28, 30.

The seal bore 80 has an inner diameter intermediate the inner diameters of the bores 28, 30 and is sized to accommodate a cylindrical rubber seal 82 to provide a seal between the bores 28 and 30. The seal 82 has flanges 84 and 86 at each end to improve sealing, and a central aperture 88 which accommodates a portion of a core of a conduit assembly and provides a seal therewith.

The conduit fitting shown in Figure 2 is mounted on the support wall 40 as described in previous paragraphs in relation to the first embodiment. Also the conduit fitting is as assembled as described in previous paragraphs in relation to the first embodiment using the assembly apparatus shown in Figure 7.

A third embodiment is shown in Figure 3 in which a conduit fitting includes the cylindrical body 21 and the spring clip member 32 described in relation to the first embodiment, together with a spring bore 94 which forms an extension of the bore 30 adjacent the face 25 of the clip receiving forward portion 24.

The spring bore 94 has a countersunk portion 95 adjacent the face 25 and an inner diameter sized to house a compression spring 92.

The conduit fitting shown in Figure 3 is mounted on the support wall 40 as described in prerious paragraphs in relation to the first embodiment.

The conduit fitting is assembled by firstly opening the cylindrical shape of the member 32 and transferring the clip member 32 on to the clip receiving forward portion 24 as described in relation to the first embodment.

Then, with reference to Figure 8, the spring clip member 32 is secured to the clip receiving forward portion 24 by an assembly procedure using an assembly apparatus in which the conduit receiving rearward portion 22 is located in the seat 50, the seat 50 having first and second bores 52, 54 sized to receive the rearward portion 22 and the flange 26 respectively. The assembly apparatus also includes a locating member 96 having a punch 98 co-axially and slidably positioned within the sizing bore 61 of the sizing ring portion 60, the sizing bore 61 communciating with the spacing bore 63 of the spacing ring portion 62.

The locating member 96 is then moved towards the conduit fitting accommodated in the seat 50 until a leading face 65 of the spacing ring portion 62 abuts against a face 51 of the seat 50. In this portion the sizing bore closely surrounds the edge 34 of the clip member 32 and the fingers 38, the fingers 38 being deflected radially inwardly by the walls of the sizing bore 61. The punch 98 is then moved towards the planar forward face 25 and into contact therewith. A central circular boss 100 on a leading face 99 of the punch 98 serves to centre the punch 98 by mating with the countersunk portion 95 of the spring bore 94.

The leading face 99 of the punch 98 is also provided with a peripheral V-shaped annular groove 102. When the punch 98 is struck the leading face 99 of the punch 98 is brought into contact with the face 25 causing metal of the face 25 to deform by flowing radially outwardly over the edge 36 of the clip member 32, the deformed metal being shaped by contact with the V shaped walls of the groove 102 into a bead which secures the clip member 32 to the clip receiving forward portion 24 and intersects smoothly with the edge 36 as seen at 104.

Figures 4, 5, and 6 show examples of conduit assemblies which are suitable for fitting on to the conduit fittings shown in Figures 1, 2 and 3. Figure 4 shows a conduit assembly 110 including an inner stranded core 112 covered by a liner 114. Covering the liner 114 is a stranded layer 11 6 about which is wound a spiral wire 118. The layer 116 and the wire 118 providing additional strength to the assembly 110. Covering the wire 118 is an outer layer 120 made of a flat strip of metal spirally wound onto the wire 118.

Figure 5 shows a conduit assembly 122 including the inner stranded core 112 covered by the liner 114 shown in Figure 4 which is covered by the outer layer 120 shown in Figure 4. The conduit assembly 122 is suitable for use in applications where additional strength provided by conduit assembly 110 is not required.

Figure 6 shows a conduit assembly 124 having the stranded inner core 112, the liner 114, and the layer 116 of conduit assembly 110 shown in Figure 4. A wire 118 is spirally wound round layer 116 in a spaced apart manner so that a flat strip 126 may be wrapped around the layer 116 between the turns of the wire 118 to provide additional strength. Covering the wire 118 and the strip 126 is an outer layer 128 of injection moulded plastic material. The conduit assembly 124 being sitable for use in applications where strength and protection from chemicals is required.

With reference to Figure 11 of the drawings the conduit fitting is located on the conduit assembly by first trimming all of the layers surrounding the core 112 to a termination face 130 leaving the core 112 extending from the face 130. The portion of the core 112 extending from the face 130 is then passed through the bores 28 and 30 of the conduit fitting to project away from the face 25 of the clip receiving forward portion 24, such that the termination face 130 abuts against a surface 29 of the bore 28 adjacent the bore 30, thereby enclosing a portion of the conduit assembly within the bore 28 of the conduit receiving portion 22. The conduit receiving portion 22 is then crimped to secure the portion of the conduit assembly within the bores 28, so securing the conduit fitting onto the conduit assembly.The crimping operation serves to avoid any change occurring in dimensions of the gap between the ends of the fingers 38 and the edge 34 abutting against the flange 26 thereby improving manufacturing tolerances.

In each of the conduit fittings described in previous paragrpahs and shqwn in Figures 1, 2 and 3 only two componerits make up the conduit fitting and only one dimensional tolerance is paramount and thereby accumulative manufacturing and assembly tolerances are substantially reduced. Because tolerance errors are reduced, a particular conduit fitting may be manufactured for a particular support wall thickness without requiring a resilient insert to achieve a good fit of the conduit fitting to the support wall.

Also the conduit fittings described in previous paragraphs are suitable for automated sub assembly as there are few components involved. Additionally the body 21 of each of the conduit fittings shown in Figures 1, 2 and 3 may be formed form a one-piece die-casting made of zinc, aluminium, brass or mild steel to aid automation.

Claims

1. A conduit fitting for anchoring a conduit assembly to a support of predetermined thickness, the conduit fitting including a body having a first portion containing a first bore for receiving the conduit assembly, a second portion for insertion through an aperture in the support, the second portion containing a second bore communicating with the first bore, an exterior flange for abutting against the support to limit the insertion of the second portion of the body into the aperture and a clip member located on the second portion of the body by a bead projecting from a deformed circumferential region of the first portion of the body, the clip member having a first end in abutting engagement with the flange and a second end extending away therefrom, and a plurality of resilient fingers diverging radially outwardly toward the first end, the plurarlity of fingers having free ends spaced a predeter mined distance from the first end, the predetermined distance being equal to the predetermined thickness of the support.

2. A conduit fitting as claimed in Claim 1, wherein the second portion of the body has a substantially cylindrical outer surface and the clip member has a complementary cylindrical inner surface.

3. A conduit fitting as claimed in Claim 1 or Claim 2, wherein the body is provided with a seal bore for accommodating a seal between the first and second bores.

4. A conduit fitting as claimed in Claim 1 or Claim 2, wherein the body is provided with a spring bore in the second portion thereof, extending from the first bore and communciating therewith, for accommodating a return spring.

5. A conduit fitting as claimed in any of the preceding claims, wherein the first portion of the body is crimped to retain the conduit assembly therein.

6. A conduit fitting as claimed in any of the preceding claims wherein the first portion, second portion, and flange are of integral construction.

7. A conduit fitting substantially as hereinbefore described with reference to the accompanying drawings.