Heatsink and heatpipes

Abstract

The invention provides a heat-pipe for a rotational molding apparatus.

Description

FIELD OF THE INVENTION[0001]This application claims Paris priority to Australian provisional application 2017904455 naming applicant THIN TANKS PTY LTD, local attorney reference 67458 DIA:JP, filed 2 Nov. 2017. This application incorporates by reference the foregoing Australian provisional application 2017904455.[0002]This invention relates primarily to the manufacture and configuration of water tanks, in particular to the production of rectangular thin tanks for domestic water storage using heat pipes within the mold to provide even and controlled heating and cooling of the mold.DESCRIPTION OF THE PRIOR ART[0003]Rotational molding is cycling process where polyethylene or other appropriate materials are placed inside a rotational mold as a powder. The mold is then heated to the desired temperature, the powder melts and, due to the rotational movement of the mold, the melted polyethylene forms an even coat over the internal surface of the mold. The process is made up of essential fou...

AI Technical Summary

Benefits of technology

The patent text describes a method of using heat pipes in a rotational mold to improve the process of removing a solidified product and reheating it for a new load of polyethylene powder. The heat pipes help to increase the rate at which heat is removed from the mold, and a small gap between the ends of the heat pipes helps to improve the structural integrity and shorten production cycles. Additionally, the heat pipes can be used without any sealed evaporating-condensing fluid, and the result is a water-tight tank.

Problems solved by technology

Molding thin tanks is a more difficult task, as it requires the structural inclusion of connections between the two vertical faces of the tank.

However, there remains an issue with such a system of molding, primarily due to the large surface area of the mold and the different shapes of product, which involve different rates of heat transfer resulting in uneven wall thickness and acute angles between surfaces can at times, depending upon the shape of the product that is being molded, result in excessive cycling times of the rotomold apparatus as well as differences in surface finish and structure.

We have observed that the stage of cooling and de-molding which are problematic when rotational molding thin tanks as due to their size the require additional cooling time to ensure that the thin walls of the structure have adequately cooled to reduce or eliminate the likelihood that the product will be de-molded whilst the polyethylene material has not adequately cooled to the appropriate temperature.

Failure to do so results in the thin plastic walls of the structure lacking the structural integrity to retain its desired shape and they begin to collapse or sag leading to deformation of the structure.

Images