Patent Application
20080130221
Thermal management considerations are important for most if not all types of computing platforms. Typically, thermal management for portable computers (e.g., notebook computers) includes the use of surface area behind a display to dissipate heat generated from components resident on the computing platform for the portable computer. This surface area and display, for example, are housed or contained in a lid that is attached to the computing platform via one or more hinges. The surface area may include one or more types of thermally conductive materials and are commonly referred to as a heat spreader. Since a lid opens and closes relative to the computing platform it is attached to, a hinge at the interface coupling the lid to the computing platform likely needs to be traversed by a cooling scheme that utilizes a heat spreader in the lid.
A commonly employed cooling scheme utilizes a heat pipe in the lid and another or second heat pipe thermally coupled to components resident on the computing platform. The heat pipes are typically fragile, thin-walled cylinders which are sealed on each end and contain a fluid such as water. The heat pipes thermally couple with one another via a hinge block along the hinge axis and this type of hinge is often referred to as a thermal hinge. Several types of thermal hinge designs are currently in use. Each of these designs share a common feature: they include a hinge pillar and allow rotation of the cylindrical heat pipe within a bore or groove that passes through the hinge block or a hollow sleeve in the hinge block. These usually require very tight tolerances and relatively elaborate fastening mechanisms to achieve a thermal hinge that has an acceptable thermal performance via the heat pipe and acceptable mechanical performance via the hinge pillar.
As mentioned in the background, thermal hinge designs usually require very tight tolerances and relatively elaborate fastening mechanisms to achieve a thermal hinge that has an acceptable thermal and mechanical performance. For acceptable thermal performance, the cylindrical surface of the heat pipe or other type of thermally conductive conduit needs to be thermally coupled with a hinge block for the thermal hinge. In some cases, thermal grease or lubricant is used to fill this gap and improve thermal conduction and also to reduce friction between the heat pipe and the hinge block as the lid is opened and closed. Unfortunately, even the use of thermal grease requires reasonably tight tolerances or fits at the hinge in order for the hinge (e.g., via the hinge pillar) to have adequate interference to provide enough mechanical torque to hold a lid open at various angles for possible viewing of a display housed in the lid. Also, tight fits may degrade a heat pipe or other type of thermally conductive conduit as rubbing causing thermal material to be worn down and lessens thermal performance. Thus, tight fit needs and wear and tear on a heat pipe or thermally conductive conduit are both problematic to a thermal hinge that has an acceptable thermal and mechanical performance
In one example, a thermal hinge couples a computing platform to a lid. The example thermal hinge includes a hinge block that has a groove passing through the hinge block and a hinge pillar to couple to the lid. In one example, the hinge pillar is inserted in a first end of the groove passing through the hinge block. The example thermal hinge also includes a thermally conductive conduit inserted in a second end of the groove passing through the hinge block. The thermally conductive conduit, for example, is to couple with a heat spreader in the lid in order to transfer thermal energy from the hinge block to the heat spreader. At least a portion of the thermal energy, for example, originates from a component resident on the computing platform.
Also depicted in
In one implementation, elements of thermal hinge 110 couple to heat spreader 132 and to heat pipe 126 to transfer thermal energy originating from component 124 to heat spreader 132. In another implementation, heat pipe 126 may be augmented with or replaced with any type of thermally conductive material (e.g., a copper, graphite, or aluminum rod/bar) to transfer thermal energy from component 124. Also, in other implementations, heat may be transferred to other types of heat absorption devices in addition to or in lieu of heat spreader 132 (e.g., a heat exchanger, heat exchanger with fan, thermoconductive conduits, etc.) located or housed within lid 130.
Although not shown in
In one example, as described more below, system 100 includes thermal hinge 110. Thermal hinge 110, for example, includes hinge block 112, hinge pillar 114 and heat pipe 116. In one implementation, hinge block 112 couples to computing platform 120 via fasteners 111a and 111b and also includes a groove 118 that passes through hinge block 112. Groove 118, for example, is shown in
In one example, hinge block 112 thermally couples to heat pipe 126. In this example, hinge block 112 is composed, at least in part, of thermally conductive materials. These materials may include, but are not limited to, aluminum, copper and graphite materials that may aid or facilitate the transfer of thermal energy or heat from heat pipe 126 to hinge block 112. As mention above, for example, heat pipe 126 may also thermally couple to component 124. Thus, in one example, thermal energy or heat from component 124 may be transferred via heat pipe 126 to hinge block 112.
In one example, similar to heat pipe 126, heat pipe 116 may also be augmented or replaced with any type of thermally conductive material (e.g., a copper, graphite, or aluminum rod/bar) to transfer thermal energy from hinge block 112 to heat spreader 132. Therefore this disclosure is not limited to only a heat pipe to couple with a hinge block for a thermal hinge to transfer thermal energy to a head spreader or other type of heat dissipation device in a lid.
In one implementation, thermal energy or heat is transferred from hinge block 112 to heat pipe 116 and then to heat spreader 132. As depicted in
In one example, hinge pillar 114 is coupled with lid 130 via hinge bracket 115. As shown in
Hinge pillar 114 and heat pipe 116, for example, are each inserted in groove 118 at a fixed length, although this disclosure is not limited to any given fixed length of insertion. This fixed length, for example, depends on the amount of mechanical torque needed by hinge pillar 114 to position a lid (e.g., lid 130) in a plurality of angles. The fixed length, for example, also depends on the amount of surface area heat pipe 116 needs to thermally couple with hinge block 112 to receive and/or absorb a desirable amount of thermal energy from hinge block 112.
In one example, groove 118 passes through hinge block 112 with a uniform diameter yet hinge pillar 114 and heat pipe 116 may have different diameters. In one implementation, as shown in
In one example, an interference fit provides mechanical torque for hinge pillar 114. This mechanical torque, for example, enables the lid to be opened and held in various positions such that a display in the lid can be viewed at different angles in relation to a computing platform the lid couples to via thermal hinge 110, e.g., 90 degrees, 130 degrees, 180 degrees, etc. Also, for example, the high interference fit may be snug or tight enough to maintain that mechanical torque over a large number of cycles (e.g., >20,000). Each cycle, for example, based on an opening and closing of the lid.
In one example, to further improve the reliability of the interference fit, one or more wear resistant rings are positioned within groove 118. For example, wear resistant ring 201 is shown in
The transition fit, as mentioned above for this example, provides a gap between heat pipe 116 and hinge block 112. This gap, for example, is shown in
As shown in
In block 420, in one example, thermal energy is transferred from component 124 resident on computing platform 120 to heat spreader 132 in lid 130 via thermal hinge 110. As described above, in one example, heat pipe 126 or a thermally conductive conduit may thermally couple to component 124 and to hinge block 112 of thermal hinge 110 to transfer heat from component 124 to hinge block 112. At least a portion of the thermal energy originating from component 124, for example, is transferred from hinge block 112 to heat pipe 116. Heat pipe 116, for example, couples with heat spreader 132 in lid 130 and further transfers at least a portion of the thermal energy originating from component 124 to heat spreader 132.
In one example, the process may start over at block 410 if thermal hinge 110 or elements coupled to thermal hinge 110 to transfer heat from component 124 are replaced. Alternatively, for example, the process may also start over at block 410 if heat is transferred from a different or an additional component resident on computing platform 120.
Referring again to
In the previous descriptions, for the purpose of explanation, numerous specific details were set forth in order to provide an understanding of this disclosure. It will be apparent that the disclosure can be practiced without these specific details. In other instances, structures and devices were shown in block diagram form in order to avoid obscuring the disclosure.
