The present invention relates to stays and props which may be used in applications such as underground mining and house re-stumping, for example.
The discussion of any prior art documents, techniques, methods or apparatus is not to be taken to constitute any admission or evidence that such prior art forms, or ever formed, part of the common general knowledge.
Wooden or steel stays and props are known to be used in environments where excavation is being carried out such as underground mining for example.
Wooden props of sufficient strength for underground mining applications are expensive and labour intensive to install. Furthermore, wood rots over time and is combustible, which is a hazard. Steel props are very heavy with those that are applicable to mining environments weighing up to two tons. Furthermore, both wooden and steel props are typically non-adjustable in height so that they must be cut to size before being transported to site.
A further problem is that it is often difficult and labor intensive to install a prop, for example in a mine. This is because the roof and floor of the mine may be uneven so that it is difficult to maneuver the prop and locate it in its desired position.
It is an object of the present invention to address one or more of the above-described problems or to at least provide a useful alternative to those props and stays that have hitherto been known in the prior art.
According to a first aspect of the present invention there is provided a prop in the form of a vessel including a base having a bottom and one or more sides;
a cover including a top and one or more sides, wherein the sides of the cover and of the base overlap each other to a maximal extent in a collapsed configuration;
Preferred features, embodiments and variations of the invention may be discerned from the following Detailed Description which provides sufficient information for those skilled in the art to perform the invention.
The Detailed Description is not to be regarded as limiting the scope of the preceding Summary of the Invention in any way. The Detailed Description will make reference to a number of drawings as follows:
Referring now to
It will be seen that the sides 13 of cover 9 substantially overlap the sides 7 of base 3 so that the overall height of the prop in the collapsed state shown in
Referring now to
It will be realised that the presence of the space 14 makes it much easier to properly install and locate the prop since it can take advantage of existing features in the environment in which it is to be installed, such as roof bolts in a mine for example.
Preferably stops (not visible) are provided on the sides of the cover and the base which cooperate to prevent the cover from being inadvertently extended so far that it becomes disengaged from the base. The stops may be overcome by rotating the base relative to the cover in order to remove the cover from the base to thereby empty the vessel of the material and all it to be returned to a collapsed state if required.
As an alternative to, or in addition to, the stops, markings or protrusions or the like may be formed upon the side of a portion of the vessel to provide a visual indicator as to when the limit of extension of the vessel is approaching or has been reached. In some embodiments the markings may be provided in the former of one or more stickers or decals that are applied to one or more portions of the vessel.
Referring now to
Additionally, handles 23 may be provided on the sides of the prop. In an alternative embodiment these may be molded into the lower part of the cover portion 9 during manufacture.
It will be realized that the prop described with reference to the figures is easily transportable in the collapsed state since it is light and relatively compact. Several such props can be loaded onto a truck to be transported and installed on site.
It will be further understood that the dimensions and proportions of the prop may be varied from that of the particular embodiment described herein. Furthermore, a prop of non-circular cross-section, e.g. square or rectangular section, might be used in some embodiments.
The prop may be made of a variety of materials including plastic, steel or fiberglass.
Where it is envisaged that the prop be used in a mining environment it will preferably be made of, or treated with, an anti-static material.
In compliance with the statute, the invention has been described in language more or less specific to structural or methodical features. The term “comprises” and its variations, such as “comprising” and “comprised of” is used throughout in an inclusive sense and not to the exclusion of any additional features. It is to be understood that the invention is not limited to specific features shown or described since the means herein described comprises preferred forms of putting the invention into effect. The invention is, therefore, claimed in any of its forms or modifications within the proper scope of the appended claims appropriately interpreted by those skilled in the art.
Number | Date | Country | Kind |
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2010903431 | Aug 2010 | AU | national |
2010257264 | Dec 2010 | AU | national |
PCT/AU2011/000919 | Jul 2011 | AU | national |
Number | Date | Country | |
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Parent | PCT/AU2011/000919 | Jul 2011 | US |
Child | 13753666 | US |