EP1600076A1

EP1600076A1 - Improvements relating to pole joints

Info

Publication number: EP1600076A1
Application number: EP05253232A
Authority: EP
Inventors: Derek Manor Cottage Bull; Paul Byard
Original assignee: Hills Ltd
Current assignee: Hills Ltd
Priority date: 2004-05-26
Filing date: 2005-05-26
Publication date: 2005-11-30
Also published as: GB0411730D0

Abstract

There is provided an attachment structure for joining two parts of a tubular pole (1), wherein the end of one part has a portion (2) of reduced cross-section to fit within the end of the other part (3), said portion having a screw thread (4) formed therein, and the other part having indents (5) punched inwardly which are staggered circumferentially and axially from one another to correspond to the pitch of the screw thread (4) and are of a depth to engage within the screw thread (4).

Description

There is often a need, such as with collapsible umbrella structures and collapsible washing line structures, to interconnect two tubular parts of a pole. One method is to provide specialised screw inserts which are fitted inside the ends of each of two parts of a pole. This is a fairly complex structure, both in terms of parts required and assembly. It is an object of this invention to provide a simplified means of interconnecting two parts of a pole.
Accordingly, there is provided an attachment structure for joining two parts of a tubular pole, wherein the end of one part has a portion of reduced cross-section to fit within the end of the other part, said portion having a screw thread formed therein, and the other part having indents punched inwardly which are staggered circumferentially and axially from one another to correspond to the pitch of the screw thread and are of a depth to engage within the screw thread.
Such a structure can readily be created by modifying a pair of tubular pole members. For example, said portion could be formed by swaging down the material of the pole. Furthermore, the screw thread can be formed by rolling the required shape into the circumference of said portion.
In a preferred form the indents are of elongated form and angled to match the angle of the screw thread. These angled indents provide a significant length of material to interengage with the screw thread. However, another possibility would be to provide a series of indents simply formed by a circular punching tool such that the combination of those indents will provide an adequate purchase with the screw thread.
Ideally the indents will be equi-angularly spaced around the circumference of the other part of the pole.
The invention may be performed in various ways and a preferred example thereof will now be described, with reference to the accompanying diagrammatic drawings, in which:
Figure 1 is a representation of two parts of a tubular pole of this invention before assembly;
Figure 2 is a side view of one of the parts of the assembly from a different angle; and
Figure 3 shows the two parts of the assembly interconnected.
Figure 1 shows two parts of a tubular pole which can be interengaged to create the central pole of a rotary drying device. It is desirable to create the pole in two (or more) parts which can be assembled together to enable them to be packed into a more compact state for transportation. One part 1 of the pole has a portion 2 at one end which is formed by swaging to a reduced cross-section so that it can fit into the sleeve defined by the other part 3 of the pole. This portion 2 then has its end rolled to define a screw thread 4. Indents 5 and 6 are punched into the tubular part 3. These indents can then engage with the screw thread 4. It will be seen that the indent 5 is staggered more towards the end of the part 3 than is the indent 6 to correspond to the pitch of the screw thread 4.
As shown in Figure 2, each of the indents 5 (and 6) is of elongated form, on an angle to match the angle of the screw thread 4. This provides a significant length of purchase of each of the indents 5 and 6 with the screw thread 4. Figure 3 shows the part 1 screwed fully home into the part 3, with the reduced portion 2 engaged wholly within the part 3 by the engagement of the screw thread 4 with the indents 5 and 6.

Claims

An attachment structure for joining two parts of a tubular pole, wherein the end of one part has a portion of reduced cross-section to fit within the end of the other part, said portion having a screw thread formed therein, and the other part having indents punched inwardly which are staggered circumferentially and axially from one another to correspond to the pitch of the screw thread and are of a depth to engage within the screw thread.
A structure according to claim 1, wherein the indents are of elongated form and angled to match the angle of the screw thread.
A structure according to claim 1 or claim 2, wherein the indents are equi-angularly spaced around the circumference of the other part of the pole.
A structure according to any one of claims 1 to 3, wherein said portion has been formed by swaging down the material of the pole.
A structure according to any one of claims 1 to 4, wherein the screw thread has been formed by rolling the required shape into the circumference of said portion.