AU2006203681A1

AU2006203681A1 - Connector device

Info

Publication number: AU2006203681A1
Application number: AU2006203681A
Authority: AU
Inventors: Philip Maurice Higgs; Francis Donald Tegg
Original assignee: Kee Klamp Ltd
Current assignee: Kee Klamp Ltd
Priority date: 2006-08-24
Filing date: 2006-08-24
Publication date: 2008-03-13

Description

INO

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AUSTRALIA

PATENTS ACT 1990 COMPLETE SPECIFICATION NAME OF APPLICANT(S):: Kee Klamp Limited ADDRESS FOR SERVICE: DAVIES COLLISON CAVE Patent Attorneys 1 Nicholson Street, Melbourne, 3000, Australia INVENTION TITLE: Connector device The following statement is a full description of this invention, including the best method of performing it known to me/us:- 5102 The invention relates to a tubular connector device suitable for use in forming a Sstructural interconnection between an end of an elongate member and a second member which may, for example, also be an elongate member. It _relates in particular, although not exclusively, to a connector device of a kind 00 IN having a protective coating and to a method of manufacture of said connector a device.

IND

OA connector device of the aforedescribed type often is used to interconnect two or more metal tubes or rods that form part of a handrail or balustrade installation, or to form a structural connection to a support such as a wall or floor. Commonly the connector device is formed of cast iron which is galvanised to provide corrosion resistance when used in external environments.

For securing the connector device to the end of a tube or rod it is customary to provide a drilled and tapped opening in a cylindrical portion of the connector device. Locking means such as a grub screw is located in that opening and can be tightened to bear firmly against an outer surface of the metal tube. This is a long established assembly technique which works efficiently.

In more severe environments corrosion can arise after a period of time at the unprotected screw thread surface of the tapped opening. This is visually undesirable and, in the event of an assembly requiring to be dismantled or modified, additional time may be incurred in separating a joint at which the screw thread is corroded. Even though the connector device may have been given a protective coating by galvanising, typically that is removed from a localised surface area when subsequently machining to form a screw threaded opening because the alternative of pre-forming the screw-thread and subjecting it to galvanising has usually resulted in poor control over quality of the screw-thread and an unacceptably high product rejection rate.

ID 2 cVarious proposals have been contemplated for protecting the screw-threaded opening against corrosion, but up to the time of the present invention these have not been successful, or add significantly to manufacturing or other costs.

In one of its aspects the present invention seeks to provide a connector device which has an improved resistance to the effects of corrosion. The invention Iseeks to provide also an improved method of manufacture of a connector device.

ICN

In one of its aspects the present invention provides a connector device comprising a tubular body portion open at at least one end and having an opening in the wall of said tubular body, at least a radially outer surface of the radially inner and outer surfaces of the tubular body portion comprising a galvanised surface finish, said opening comprising a screw-thread formation, said opening being bereft of said galvanised surface finish and the screwthreaded formation in said opening having had applied thereto a liquid based protective layer which contains particulate material.

Preferably the whole of said non-galvanised surface of the opening has been provided with said liquid based protective layer.

The invention provides also a connector device assembly comprising said connector device of the invention in combination with a screw-threaded fastener such as a grub screw positioned in said opening with said liquid based protective layer being present between confronting surface regions of the opening and screw-threaded fastener.

In another of its aspects the present invention provides a method of manufacture of a connector device comprising providing a tubular body portion, subjecting at least the radially outer of the radially inner and outer surfaces of the tubular body to a galvanising treatment, subsequently forming in the wall of said tubular body a screw-threaded opening, and then applying to said screw- Sthread of said opening a liquid based protective layer which contains

O

N particulate material.

The invention provides also a method of forming a connector device assembly ccomprising said connector device and a screw-threaded fastener wherein said screw-threaded fastener is inserted into the screw-threaded opening subsequent to application of said liquid based protective layer.

The liquid based protective layer which contains particulate material, such as C finely divided metal particles, may provide for example a surface appearance Swhich blends with that of the galvanised outer surface of the connector device.

Suitable particles include zinc and aluminium particles. Preferably the particles have a maximum size of 25 micron. Maximum sizes less than 10 microns are particularly suitable.

Suitable materials for the tubular body of the connector device include cast iron and steel.

One embodiment of the present invention will now be described by way of example only, with reference to the accompanying drawings in which:- Figure 1 is a perspective view of a connector device of the present invention in situ to join two tubular members, and Figure 2 is a longitudinal section of the connector device of Figure 1.

A connector device 12 for the in-line connection of two tubes 13,14 has a tubular cast iron body 15 which is provided with a small boss 16 near to each end 17. The bosses 16 each have screw-threaded passages 18 which extend through the wall of the tubular body 15 in a direction radially outwards from a major longitudinal axis 19 of the connector device.

The tubular body is formed by casting to create the integral formation of a N tubular body and bosses 16 and is then subject to galvanising to protect tb against corrosion prior to a machining operation to form the screw-threaded passages 18.

A liquid based protective layer is then applied to the whole of the machined surfaces prior to insertion of a grub screw 20 into each screw-threaded IN: passage 18. Said liquid based protective layer is of a kind which, in this embodiment of the invention comprises 8 microns diameter particles of zinc Isuch that in the resulting connector device assembly of the connector device Sand grub screws, exposed outer regions of the screw-threaded passage 18, when the grub screw is in the fully inserted position to bear against a respective tube 13, 14, has a visual appearance corresponding substantially with that of the galvanised radially outer surface of the tubular body

Claims

1. A connector device comprising a tubular body portion open at at least j- one end and having an opening in the wall of said tubular body, at least a radially outer surface of the radially inner and outer surfaces of the tubular body portion comprising a galvanised surface finish, said opening comprising a 00 NOscrew-thread formation, said opening being bereft of said galvanised surface finish and the screw-threaded formation in said opening having had applied O thereto a liquid based protective layer which contains particulate material.

2. A connector device according to claim 1, wherein the whole of said non- galvanised surface of the opening has been provided with said liquid based protective layer.

3. A connector device according to claim 1 or claim 2, wherein said particulate material comprises finely divided metal particles which have a maximum size of 25 micron.

4. A connector device according to claim 3, wherein said particles have a maximum size less than 10 micron.

A connector device according to claim 3 or claim 4, wherein said particulate material comprises particles of zinc or aluminium.

6. A connector device according to claim 1 and substantially as herein before described.

7. A connector device assembly comprising a connector device according to any one of the preceding claims in combination with a screw-threaded fastener positioned in said opening with said liquid based protective layer present between confronting surface regions of the opening and screw- threaded fastener.

8. Method of manufacture of a connector device comprising providing a 3 tubular body portion, subjecting at least the radially outer of the radially inner and outer surfaces of the tubular body to a galvanising treatment, subsequently N forming in the wall of said tubular body a screw-threaded opening, and then applying to said screw-thread of said opening a liquid based protective layer which contains particulate material. 0 INO

9. Method of forming a connector device assembly comprising a connector (Ni Ndevice according to any one of claims 1 to 7 and a screw-threaded fastener, wherein said screw-threaded fastener is inserted into the screw-threaded opening subsequent to application of said liquid based protective layer.

Method according to claim 8 or claim 9, wherein the whole of the non- galvanised surface of the opening is provided with said liquid based protective layer.

11. Method according to any one of claims 8 tolO, wherein said particulate material comprises finely divided metal particles which have a maximum size of 25 micron.

12. Method according to claim 11, wherein said particulate material comprises finely divided metal particles which have a maximum size less than micron.

13. Method according to any one of claims 8 to 12, wherein said particulate material comprises particles of zinc or aluminium.

14. Method according to claim 8 or claim 9, and substantially as hereinbefore described. DATED this TWENTY FOURTH day of AUGUST 2006 Kee Klamp Limited by DAVIES COLLISON CAVE Patent Attorneys for the applicant(s)