GB2275581A - Conduit fitting - Google Patents

Description

2275581 CONDUIT FITTING This invention relates to a conduit fitting, such

as a terminal box or junction box, of the kind comprising a main housing portion, and at least one conduit entry to receive a conduit.

It is known to produce conduit fittings from two parts each of which are made from metal pressings. Each part includes a portion for the or each conduit entry. The two parts may then be welded together, as for example in GB 1 479 821.

More recently it has become the practice to form the fitting in two parts, a main part or housing and a lid. The housing is formed by pressing, and then the conduit entries are welded to the housing to complete the housing. The fitting is then sealed by the lid which contacts the main part of the fitting. The edges of the lid extend to the outer edge of the fitting.

Such constructions suffer from a number of disadvantages. One particular problem is caused because the conduits and the conduit entries are circular in form. Thus in use dirt accumulates behind the conduits and particularly at the conduit fitting by the conduit entry. This is a particular disadvantage when such fittings are installed in breweries, food or pharmaceutical factories, where the cleaning of such fittings may require production to be halted.

According to our invention in a fitting of the kind set forth a rear surface of the housing portion is contiguous with a back surface of the or each conduit entry.

2 The two rear and back surfaces may conveniently form a single, planar, flat surface. This surface then fits against a wall and prevents dirt accumulating behind the conduit entry.

When the f itting is provided with more than one entry, a web co-planar with the rear surface of the housing portion is provided between adjacent conduit entries.

When the fitting is installed a layer of sealant between the edge of the fitting and the wall will prevent dirt and other contaminants from entering the interface between the fitting and the wall.

Such a fitting may also be provided with a resilient pad, both to fix the fitting against a roughened wall surface, for example a pebble dashed wall, and to space the fitting both from the wall and towards the conduit with which it is to connected.

The fitting may be provided with bolt recesses so arranged that bolts do not pass within an enclosed volume of the fitting.

Some embodiments of the invention will now be described by way of example only, with reference to the accompanying drawings, in which:- Figure 1 shows a perspective view of a fitting according to the invention, with a single conduit entry; Figures 2 and 3 show opposite side elevations of such a fitting; 3 Figure 4 shows a plan view f rom beneath of such a f itting; Figure 5 shows a plan view from above such a fitting; Figure 6 shows an end view of such a fitting; Figure 7 shows a plan view of a fitting according to the invention with two entry conduits; Figure 8 shows a section along the line 8-8 of Figure 7; Figure 9 shows a plan view of a fitting according to the invention with three entry conduits; Figure 10 shows a section along the line 10-10 of Figure 9; Figure 11 shows a plan view of a fitting according to the invention with four entry conduits; Figure 12 shows a section along the line 12-12 of Figure 11; Figure 13 shows a view f rom beneath of a branch two-way conduit according to one aspect of the invention; Figure 14 shows a top plan view of the embodiment of Figure 13; 4 Figure 15 shows an end view' of the embodiment of Figure 13; Figure 16 shows an opposite end view to that of Figure 15; and Figure 17 shows a side view of the embodiment of Figure 13.

Referring to the drawings, Figure 1 shows a conduit fitting comprising a housing portion 1. The housing portion 1 comprises a base 2 and upstanding wall 3 and a single conduit entry 4 formed from a single casting.

At the top of the wall 3 there is a rim or lip 5. The lip 5 is internally recessed to form a shoulder 6. The wall 3 extends inwards at diametrically opposite points to form bolt recesses 7,8. The top surfaces of these recesses are level with the shoulder 6.

A lid 9 is provided with holes 10,11 through which bolts extend. The holes may be recessed/countersunk to receive the bolt heads. In the embodiment of Figures 1 to 6 the bolts secure the lid 9 to the housing portion 1 and may also secure the housing portion 1 to the surface to which it is to be attached.

In an alternative embodiment (Figures 7 to 12) in which -the bolts are used only to secure the lid 9 to the housing portion the shoulder itself extends beyond the internal surface of the wall to form bolt receiving portions 47,48.

The lid 9 fits within the recess such that the top surface of the lid 12 is level with the top surface of the lip 5, when a seal or gasket is in place between the housing portion 1 and the lid 9.

Preferably the lid is smaller than the recessed portion of the lip to allow a gap between the edge of the lid 13 and the internal edge 14 of the rim, through which the gasket (not shown) may be visible.

An earth terminal 15 is shown in the drawings. This may be formed from the wall 3 rising from the floor 2, or formed as an extension of the wall 3. The terminal comprises a recess 16, cruciform in shape, within a platform 17.

As shown in Figure 4 the base 2 of the fitting may form a single surface with the base 23 of the conduit entry 4.

The conduit fittings may be provided with a recess 18, in the same manner as the top of the fitting in order to allow the fitting of a visible seal between the conduit entry and the conduit to enter.

The conduit fitting is provided with a further recess 19 into which a flexible locking blade or clip is inserted. This clip acts upon a conduit to be inserted in a known manner. The clip protrudes from within its recess at an angle once inserted. Once a conduit has been inserted, in order for it to be withdrawn, it must be unscrewed. Accordingly such a fitting may also be used with a conduit having a suitable external thread.

The internal diameter of the conduit entry 20 may conveniently be slightly smaller than that of the hole 21 communicating the conduit entry with the 6 internal volume of the fitting. This provides an abutment surface 22 which prevents the conduit once within the conduit entry from entering the fitting itself.

Figure 7 shows a conduit f itting with two conduit entries 30,31. The conduit entries in the embodiment shown are at 900 to one another but may be at any suitable angle. Similarly, while Figures 9 and 11 show conduit fittings with three and four conduit entries respectively in which each conduit entry is at 900 to at least one another conduit entry, other spacings of the conduit entries are envisaged.

For example in the two conduit entry conduit fitting the conduit entries may be adjacent one another in the known branch two-way or U-formation conduit fitting.

An example of a branch two-way conduit fitting is shown in Figures 13 to 17. Where appropriate like reference numerals refer to like parts.

This conduit fitting shows the use of a web 40 between each of the conduits 41, 42. This web prevents the build up of dirt between the conduit entries of the fitting. It also enables the fitting to be cleaned more effectively than would be the case if the web were absent.

7

Claims (14)

1. A conduit fitting of the kind set forth in which a rear surface of the housing portion is contiguous with a back surface of the or each conduit entry.

2. A conduit f itting as claimed in claim 1, in which the two surfaces form a single, planar, flat surface.

3. A conduit fitting as claimed in claim 1 or claim 2, in which the fitting is provided with more than one entry, and a web co-planar with the rear surface of the housing part is provided between adjacent conduit entries.

4. A conduit fitting as claimed in any preceding claim, in which the fitting is provided with a resilient pad, to fix the fitting against a wall, and to space the fitting from the wall to facilitate conduit connection.

5. A conduit fitting as claimed in any preceding claim, in which the housing portion is provided with bolt recesses so arranged that bolts do not pass within an enclosed volume of the fitting.

6. A conduit f itting as claimed in claim 5, in which the housing portion has an open mouth and a lid adapted to close the mouth is secured to the housing portion by the bolts.

7. A conduit fitting as claimed in any preceding claim lf in which at least the body portion is formed by die-casting.

8 8. A conduit fitting or claimed in any preceding claim, in which the body portion is cast in zinc alloy.

9. A conduit fitting as claimed in any of claims 1-7, in which the body portion is cast in stainless steel.

10. A conduit fitting as claimed in any of claims 7-9, in which the body is provided with an integral earth terminal.

11. A conduit fitting as claimed in any of claims 7-10, in which the conduit entry is formed within its length with a recess to accommodate a flexible locking blade or clip.

12. A conduit fitting as claimed in any preceding claim, in which the fitting is treated with a non-stick coating.

13. A conduit fitting as claimed in claim 12, in which the non-stick coating in Teflon.

14. A conduit fitting as claimed in claim 1, and substantially as described herein with reference to and as illustrated in the accompanying drawings.