US20150136359A1

US20150136359A1 - Flexible heat transfer assembly

Info

Publication number: US20150136359A1
Application number: US14/084,284
Authority: US
Inventors: Cheng-Hsiu Ku
Original assignee: NEWTECH ENTERPRISE Ltd
Current assignee: NEWTECH ENTERPRISE Ltd
Priority date: 2013-11-19
Filing date: 2013-11-19
Publication date: 2015-05-21

Abstract

A flexible heat transfer assembly includes a covering layer (100) and a functional filler (200). The covering layer (100) surroundingly forms a sealed chamber (11), in which the material of the covering layer (100) is one of rubber, silica rubber, and resin. The functional filler (200) is filled in the sealed chamber (110). The functional filler (200) comprises at least one of silicone, silicone oil, silica gel, and paraffin, and at least one of ceramic powder, metal powder, metal oxide powder, and graphene. By means of the covering layer (100) tightly attached to a heat-generating part and by means of the heat transfer of the functional filler (200), the flexible heat transfer assembly can absorb or dissipate the heat generated by the heat-generating part.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention
The present invention relates to a heat-absorbing device, and in particular, to a flexible heat transfer assembly.
2. Description of Related Art
The integrated circuits disposed in a general mobile electronic device (for example, a notebook computer and a smart phone) comprise active elements such as transistors. Heat is generated by theses active elements when they perform operations. As the performance requirement of the mobile electronic devices increases, more transistors have to be disposed in the integrated circuits, resulting in more and more heat generated. However, the surface of the chip is not increased accordingly and thus the heating density of the electronic device increases, causing the over-temperature problem of the heat-generating part. According to the 10° C. theory (i.e., the Arrhenius Law), a rise in temperature of the heat-generating part by 10° C. will halve the effective lifetime thereof. Therefore, the temperature control of the electronic product is considerably important.
According to the statistical data, the damaged electronic devices caused by over-heating is over 50% of all the damaged ones. Over-temperature not only damages semiconductor devices, but also degrades the reliability and operating performance thereof. In particular, the recent development trend of electronic products has been towards a high-performance, high-speed, and compact design. Thus, the heat dissipation issue of electronic products causes a technical bottleneck of related products and becomes necessary to be considered. It is therefore necessary to look for a total solution, of package level, PCB-level, and system level, to the heat dissipation issue.
Since the heat-generating part (e.g., CPU) and metal heat dissipator are both solid, from a microscopic viewpoint, there are lots of pores, defects, and scratches on the surfaces of them; thus air will be easily trapped therein during the assembling of the heat-generating part and the metal heat dissipator. Due to the poor heat transfer rate of the air, the efficiency of the whole heat transfer will degrade.
Today's mobile electronic devices develop continuously into a light, thin, short, and compact design and so do their various mechanical parts. During the assembling, if the compressibility of the flexible heat-absorbing device is poor, it is possible to create an uneven exertion of forces among the mechanical parts and deform them.
In view of this, the inventor pays special attention regarding the above existing technology to research with the application of related theory and tries to overcome the above disadvantages, which becomes the goal of the inventor's improvement.

SUMMARY OF THE INVENTION

The main objective of the present invention is to provide a flexible heat transfer assembly. To achieve the above objective, the present invention provides a flexible heat transfer assembly comprising a covering layer and a functional filler. The covering layer surroundingly forms a sealed chamber, in which the material of the covering layer is one of rubber, silica rubber, and resin. The functional filler is filled in the sealed chamber, in which the functional filler comprises at least one of silicone, silicone oil, silica gel, and paraffin, and at least one of ceramic powder, metal powder, metal oxide powder, and graphene (powder or sheet).
Preferably, in the above-mentioned flexible heat transfer assembly, the resin is one of polyethylene, polypropylene, polyethylene terephthalate, polycarbonate, polyurethane, thermoplastic polyurethane, silicone, and low-density polyethylene.
Preferably, in the above-mentioned flexible heat transfer assembly, the rubber is one of natural rubber and synthetic rubber.
Preferably, in the above-mentioned flexible heat transfer assembly, the resin is one of ethylene acid resin, acrylic resin, organosilicon resin, and urethane resin.
Preferably, in the above-mentioned flexible heat transfer assembly, the metal powder comprises at least one of copper powder, aluminum powder, gold powder, silver powder, and iron powder.
Preferably, in the above-mentioned flexible heat transfer assembly, the ceramic powder comprises at least one of aluminum oxide powder, boron nitride powder, calcium carbonate powder, and aluminum nitride powder.
Preferably, in the above-mentioned flexible heat transfer assembly, the metal oxide powder comprises at least one of iron oxide powder, magnesium oxide powder, and calcium oxide powder.
Preferably, in the above-mentioned flexible heat transfer assembly, the covering layer has a thickness ranging from 0.02 mm to 5 mm. Preferably, in the above-mentioned flexible heat transfer assembly, the functional filler has a thickness ranging from 0.01 mm to 6 mm.
Preferably, the above-mentioned flexible heat transfer assembly further comprises a micro vibrator attached to the covering layer.
Preferably, the above-mentioned flexible heat transfer assembly further comprises a micro pressurizing member attached to the covering layer.
The flexible heat transfer assembly of the present invention can reduce the surface temperature of the heat-generating part and maintain its operational performance by means of the covering layer tightly attached to the heat-generating part and by means of the functional filler, in the covering layer, dissipating the heat generated by the heat-generating part. Further, the flexible heat transfer assembly of the present invention can use a micro vibrator or a micro pressurizing member to enhance the mobility of the functional filler and thus enhance the heat transfer efficiency thereof.

BRIEF DESCRIPTION OF DRAWING

FIG. 1 is a schematic view of the flexible heat transfer assembly according to the first embodiment of the present invention;

FIG. 2 is a schematic view of the flexible heat transfer assembly according to the second embodiment of the present invention;

FIG. 3 is a schematic view of the flexible heat transfer assembly of another aspect according to the second embodiment of the present invention;

FIG. 4 is a schematic view of the flexible heat transfer assembly of yet another aspect according to the second embodiment of the present invention;

FIG. 5 is a schematic view of the flexible heat transfer assembly of still yet another aspect according to the second embodiment of the present invention; and

FIG. 6 is a schematic view of the flexible heat transfer assembly according to the third embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIG. 1, it is provided the flexible heat transfer assembly according to the first embodiment of the present invention. The flexible heat transfer assembly comprises a covering layer 100 and a functional filler 200. The covering layer 100 surroundingly forms a sealed chamber 110. The functional filler 200 is filled in the sealed chamber 110.
The covering layer 100 is made of retractable material of elasticity, toughness and recoverability. The covering layer 100 preferably has a thickness ranging from 0.02 mm to 5 mm. The material of the covering layer 100 is preferably one of rubber, silica rubber, and resin (or called plastic). The rubber may be one of natural rubber and synthetic rubber. The resin may be one of ethylene acid resin, acrylic resin, organosilicon resin, urethane resin, polyethylene terephthalate (PET), and Polycarbonate (PC), in which the ethylene acid resin may be one of polyethylene (PE) and low density polyethylene (LDPE); the acrylic resin may be, for example, polypropylene (PP); the organosilicon resin may be, for example, silicone; the urethane resin may be, for example, one of polyurethane (PU) and thermoplastic polyurethane (TPU).
The functional filler 200 is a mixture comprising carriers and additives. The carriers may be preferably one of silicone, silicone oil, silica gel, and paraffin, or any combination thereof. The additives may be at least one of ceramic powder, metal powder, metal oxide powder, and graphene. The ceramic powder may be, for example, one of aluminum oxide (Al₂O₃) powder, boron nitride (BN) powder, calcium carbonate (Ca₂CO₃) powder, and aluminum nitride (AlN) powder, or any combination thereof. The metal powder may be, for example, one of copper powder, aluminum powder, gold powder, silver powder, and iron powder, or any combination thereof. The metal oxide powder may be, for example, one of iron oxide powder, magnesium oxide powder, and calcium oxide powder, or any combination thereof. The functional filler 200 preferably has a thickness ranging from 0.01 mm to 6 mm and The flexible heat transfer assembly of the present invention preferably has a total thickness ranging from 0.15 mm to 10 mm.
Referring to FIG. 2, it is provided the flexible heat transfer assembly according to the second embodiment of the present invention. The flexible heat transfer assembly comprises a covering layer 100, a functional filler 200, and a micro vibrator 310. The covering layer 100 and the functional filler 200 are the same as those of the first embodiment described above. The parts of the second embodiment which are the same as those of the first embodiment will not be described again. The differences between the second embodiment and the first embodiment will be described below in detail. The micro vibrator 310 is attached to the covering layer 100. In the second embodiment, the micro vibrator 310 is preferably attached to or embedded on the external surface of the covering layer 100; however, the present invention is not limited to this. For example, the micro vibrator 310 may be attached to or embedded on the internal surface of the covering layer 100, as shown in FIG. 3. Further, the micro vibrator 310 may be embedded within the covering layer 100, as shown in FIG. 4. In addition, the flexible heat transfer assembly of the present invention may be provided with a plurality of micro vibrators 310, as shown in FIG. 5. The micro vibrator 310 can produce vibration to further enhance the mobility of the functional filler 200 and thus accelerate the heat transfer thereof.
Referring to FIG. 6, it is provided the flexible heat transfer assembly according to the third embodiment of the present invention. The flexible heat transfer assembly comprising a covering layer 100, a functional filler 200, and a micro pressurizing member 320. The covering layer 100 and the functional filler 200 are the same as those of the first embodiment described above. The parts of the third embodiment which are the same as those of the first embodiment will not be described again. The differences between the third embodiment and the first embodiment will be described below in detail. The micro pressurizing member 320 is attached to the covering layer 100. In the third embodiment, the micro pressurizing member 320 is preferably attached to or embedded on the external surface of the covering layer 100; however, the present invention is not limited to this. For example, the micro pressurizing member 320 may be attached to or embedded on the internal surface of the covering layer 100; it also may be embedded within the covering layer 100. In addition, the flexible heat transfer assembly of the present invention may be provided with a plurality of micro pressurizing members 320 which are disposed in the same way as the micro vibrators 310 described in the second embodiment. The micro pressurizing member 320 produces pressure difference to further enhance the mobility of the functional filler 200 and thus accelerate the heat transfer thereof.
For the practical application of the flexible heat-absorbing device under compressed conditions, the flexible heat transfer assembly of the present invention can expel the air trapped in the pores, defects, and scratches and be tightly attached to the irregular surface of the heat-generating part, thereby enhance the whole heat transfer efficiency. The present invention can absorb, convey, insulate, and slowly dissipate the heat generated by the heat-generating part, thus effectively reducing the surface temperature of the heat-generating part and making it operate for a long time.
The flexible heat transfer assembly of the present invention can select the functional filler material with different properties based on different requirements such that the flexible heat transfer assembly of the present invention has wider applicability.
The covering layer of the flexible heat transfer assembly of the present invention has properties of elasticity, toughness, and recoverability; therefore, its shape can be adjusted according to different use states. Also, even when an error occurs during the assembling of the flexible heat transfer assembly of the present invention, the error can be removed and the flexible heat transfer assembly can be reworked without damage to the structure thereof, thus reducing the consumption of rework materials and the cost of rework.
The embodiments described above are only preferred ones of the present invention and not to limit the scope of appending claims regarding the present invention. Therefore, all the equivalent modifications applying the spirit of the present invention should be embraced by the scope of the present invention.

Claims

What is claimed is:

1. A flexible heat transfer assembly, comprising:

a covering layer (100) surroundingly forming a sealed chamber (110), wherein the material of the covering layer (100) is one of rubber, silica rubber, and resin; and

a functional filler (200) filled in the sealed chamber (110), wherein the functional filler (200) comprises at least one of silicone, silicone oil, silica gel, and paraffin, and at least one of ceramic powder, metal powder, metal oxide powder, and graphene.

2. The flexible heat transfer assembly according to claim 1, wherein the resin is one of polyethylene, polypropylene, polyethylene terephthalate, polycarbonate, polyurethane, thermoplastic polyurethane, silicone, and low-density polyethylene.

3. The flexible heat transfer assembly according to claim 1, wherein the rubber is one of natural rubber and synthetic rubber.

4. The flexible heat transfer assembly according to claim 1, wherein the resin is one of ethylene acid resin, acrylic resin, organosilicon resin, and urethane resin.

5. The flexible heat transfer assembly according to claim 1, wherein the metal powder comprises at least one of copper powder, aluminum powder, gold powder, silver powder, and iron powder.

6. The flexible heat transfer assembly according to claim 1, wherein the ceramic powder comprises at least one of aluminum oxide powder, boron nitride powder, calcium carbonate powder, and aluminum nitride powder.

7. The flexible heat transfer assembly according to claim 1, wherein the metal oxide powder comprises at least one of iron oxide powder, magnesium oxide powder, and calcium oxide powder.

8. The flexible heat transfer assembly according to claim 1, wherein the covering layer (100) has a thickness ranging from 0.02 mm to 5 mm.

9. The flexible heat transfer assembly according to claim 1, wherein the functional filler (200) has a thickness ranging from 0.01 mm to 6 mm.

10. The flexible heat transfer assembly to claim 1, further comprising a micro vibrator attached to the covering layer (100).

11. The flexible heat transfer assembly to claim 1, further comprising a micro pressurizing member attached to the covering layer (100).