The invention relates to heat-transfer techniques. More specifically, the present invention relates to compact, passive cooling components for use in electronic devices. According to Apple, the system includes a power source and a heat-shield mechanism which encloses the power source. This heat-shield mechanism includes a 3-dimensional housing that defines a cavity in which the power source resides, and a plate that is positioned to cover an opening to the cavity that is defined by an edge of the housing.
Note that the housing contains three layers in which a second layer is sandwiched between a first layer and a third layer. This second layer has a first anisotropic thermal conductivity. Furthermore, the plate includes a material having a second anisotropic thermal conductivity.
Here's Apple's summary of the invention:
One embodiment of the present invention provides a system that includes a power source and a heat-shield mechanism which encloses the power source. This heat-shield mechanism includes a 3-dimensional housing that defines a cavity in which the power source resides, and a plate that is positioned to cover an opening to the cavity defined by an edge of the housing. Note that the housing contains three layers in which a second layer is sandwiched between a first layer and a third layer. This second layer has a first anisotropic thermal conductivity. Furthermore, the plate includes a material having a second anisotropic thermal conductivity.
In some embodiments, the first layer and the third layer include metal, such as aluminum, copper, magnesium, an aluminum alloy, a copper alloy, and/or a magnesium alloy. In some embodiments, the plate is covered by an overcoat. This overcoat may include a polymer, such as Mylar.
In some embodiments, the plate is coupled to a surface inside of the system, for example, using an adhesive. In some embodiments, the second layer includes graphite and the plate includes graphite.
In some embodiments, the power source is associated with an integrated circuit. Furthermore, in some embodiments the heat-shield mechanism provides passive cooling of the power source. In some embodiments, the system includes a portable computing device.
In some embodiments, the system operates to ensure a temperature on an outer surface of the system is less than a first pre-determined value and/or a temperature inside of the heat-shield mechanism is less than a second pre-determined value. In some embodiments, the housing has a weight less than a pre-determined value.
The inventor is Ihab A. Ali. The graphic below illustraties a portable computing device in accordance with an embodiment of the present invention.