Patent Publication Number: US-2022236752-A1

Title: Biologically Temperature-Controlled Electronics Shell Component

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a shell component and, more particularly, to an electronics shell component with biological temperature control and heat exchange functions. 
     2. Description of the Related Art 
     The advanced semiconductor technologies are credited with exquisite electronics such as mobile phones and tablet devices characteristic of ultrathin appearances, diversified functions and dazzling capacities for activations of APPs. Moreover, the broadband speed is crucial to internet users increasingly. However, the issue of how to effectively dissipate heat derived from operational semiconductor components (for example, CPU) for smooth running of a semiconductor-based device is critically important. 
     As an electronic substrate installed inside ordinary electronics (for example, mobile phone, tablet device, laptop computer and desktop computer), a printed circuit board features its top and back sides, coated and sealed, to prevent circuits from moisture-induced oxidation that works against operations of semiconductor components. However, heat derived from an operational semiconductor component must be sustained by the semiconductor component itself rather than dissipated from the coated and sealed PCB. Accordingly, some manufacturers install heat dissipation films on the top edges of the semiconductor components to dissipate heat, or some manufacturers install radiant heat absorbers, condenser pipes, thermal conduction rods or heat pipes around heat sources of the semiconductor components and extend the condenser pipes, the thermal conduction rods or the heat pipes to low-temperature regions in the device bodies, so that the heat from the semiconductor components can be uniformly distributed. Furthermore, an alloy case installed over a high-end mobile phone is meant to further conduct thermal radiation inside the mobile phone. 
     The trend of electronics is to emphasize a portable product with a compact size. A thinner electronic product (especially a mobile phone or a tablet device) should accommodate cooling parts scaled down to ultrathin sizes. However, heat conduction based on scaled-down cooling parts is ineffective and results in poor efficiency of heat dissipation. Moreover, a mobile phone or a tablet device provided with a sealed substrate and semiconductor components thereon features the airtight space inside a device body in which cross-ventilation is extremely limited and dramatically rising thermal radiation is almost unsolved. Specifically, heat accumulation common in a mobile phone or a tablet device has negative effects on the operational device, such as hot shutdown, hot failure of a semiconductor chip, device body burning hot and battery overheated or damaged. For a high-end mobile phone equipped with a metal case and abovementioned cooling parts, the semiconductor component mostly encapsulated in an airtight space bears the brunt of poor heat dissipation that works against moderation of heat accumulation at the operational semiconductor component in the sealed airtight space. Particularly, the chips of a 5G mobile phone consumes 2.5 times as much electric power as those of a 4G mobile phone, according to statistic data, worsening heat accumulation that will increase exponentially. Furthermore, a middle shell body is installed inside the device body of a high-end mobile phone from which more heat is generated by operational semiconductor components and used to prevent a user from scalds attributed to heat conducted by the outer shell body directly. However, the functions of the mobile phone are seriously affected because the middle shell body on which no heat conductor is mounted makes no contribution to dissipation of heat accumulated inside. 
     Document US20150216081A1 discloses a heat dissipation mechanism for handhold electronic apparatus, which comprises a thin metal sheet and at least one heat pipe joined to the thin metal sheet. The heat dissipation mechanism is designed to enhance the heat dissipation performance of the handheld electronic apparatus, avoiding damage to the handheld electronic apparatus or its components. The document does, however, not provide a satisfactory solution of the above mentioned problems. 
     BRIEF SUMMARY OF THE INVENTION 
     Therefore, it is an objective of the present invention to overcome the aforementioned shortcoming and deficiency of the prior art by providing a biologically temperature-controlled electronics shell component which serves as the outer shell as well as the middle shell in different types of mobile phones, tablet devices or wearable devices and contributes to fast conduction of radiant heat accumulation from heat sources (for example, semiconductor components) inside the device body of electronics through the shell component to outside for effective temperature control and normal operations of the semiconductor components. 
     The biologically temperature-controlled electronics shell component of the present invention includes an outer shell body and an outer heat-conducting sheet. The outer shell body is adapted to be combined with a device body of an electronic product, and the device body has a heat source therein. The outer shell body includes opposite inner and outer surfaces and at least one hole penetrating the inner and outer surfaces. The outer heat-conducting sheet is combined with the outer shell body and includes opposite inner and outer end faces and at least one heat-conducting portion. The inner end face of the outer heat-conducting sheet faces the heat source of the electronic product. The at least one heat-conducting portion corresponds to the at least one hole in the outer shell body, so that the heat-conducting portion can be contacted by a user through the hole. The outer heat-conducting sheet further includes a periphery surrounding the heat-conducting portion and combined with the outer shell body. 
     In an embodiment, the electronic product is one of a mobile phone, a tablet device, a laptop computer, a WiFi relay unit, a LED lamp, a solar power connection box, a solar inverter and a wearable device. The outer shell body is made of a plastic material, the outer heat-conducting sheet is made of a metal material, and the heat-conducting portion is composed of a convex portion protruding outward from the outer end face and embedded in the hole of the outer shell body. 
     In an embodiment, the heat-conducting portion is composed of a convex portion protruding outward from the inner end face. 
     In a preferred form, the outer heat-conducting sheet is provided with a plurality of pinholes in which plastic is injected such that the periphery of the outer heat-conducting sheet is encased in the outer shell body for integral combination. 
     In a preferred form, the periphery of the outer heat-conducting sheet is provided with a flange, and the outer end face of the outer heat-conducting sheet is provided with a plurality of sharpened convex granules. The flange and the convex granules of the outer heat-conducting sheet are fused with the outer shell body such that the outer heat-conducting sheet is fused with the inner surface of the outer shell body. 
     In an embodiment, the at least one hole includes a plurality of holes and is arranged adjacent to sides of the outer shell body. The periphery of the outer heat-conducting sheet extends to a circumference of the inner surface of the outer shell body. 
     In an embodiment, the electronics shell component further comprises a middle shell body and an inner heat-conducting sheet. The middle shell body is installed in the device body of the electronic product and includes opposite inner and outer surfaces and a hole penetrating the inner and outer surfaces. The inner heat-conducting sheet is combined with the middle shell body and corresponds to the heat source. The inner heat-conducting sheet is located between the outer heat-conducting sheet and the heat source and includes a heat-conducting portion corresponding to the hole of the middle shell body. The inner heat-conducting sheet further includes a periphery surrounding the heat-conducting portion of the inner heat-conducting sheet and engaged with the middle shell body. 
     In practice of the shell component of the present invention, an outer shell (or an outer shell and a middle shell) of an existing electronic product (for example, mobile phone, tablet device, laptop computer, WiFi router, WiFi outdoor relay unit, solar power connection box, inverter, LED bulb, projector lamp, etc.) can be substituted by the shell component having the identical model or size without any modification inside the existing electronic product in structure for effective conduction of radiant heat from the device body to outside and fast heat conduction and dissipation effects. Specifically, the heat-conducting sheet on the shell component quickly absorbs radiant heat generated by a heat source inside the electronic product and radiant heat is dissipated outward from the device body through the heat-conducting portion for moderate heat accumulation of semiconductor components operating in an airtight space. Moreover, radiant heat generated by the heat source is quickly conducted through the heat-conducting portion contacted by a user&#39;s skin (fingers also) for heat conduction and dissipation by biological temperature control of the human body. Furthermore, the shell component of the present invention is applicable to an electronic product (for example, mobile phone or a wearable/smart device) which will be shut down for protecting a battery in low-temperature status. With a heat conduction sheet contacted by fingers or skin, heat from body temperature is conducted by the heat conduction sheet and radiated into the device body for higher temperature inside an airtight space and no shutdown in case of the battery at low-temperature status. 
     The present invention will become clearer in light of the following detailed description of illustrative embodiments of this invention described in connection with the drawings. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
       The illustrative embodiments may best be described by reference to the accompanying drawings where: 
         FIG. 1  is an exploded view of an electronics shell component according to a first embodiment of the present invention. 
         FIG. 2  is a perspective view of the shell component of  FIG. 1 . 
         FIG. 3  is a sectional view of the shell component of  FIG. 1 . 
         FIG. 4  is a schematic view of the shell component of  FIG. 1  used in a mobile phone. 
         FIG. 5  is an exploded view of an electronics shell component according to a second embodiment of the present invention. 
         FIG. 6  is a sectional view of the shell component of  FIG. 5 . 
         FIG. 7  is a sectional view similar to  FIG. 3  illustrating a shell component according to a third embodiment of the present invention. 
         FIG. 8  is a sectional view similar to  FIG. 3  illustrating a shell component according to a fourth embodiment of the present invention. 
         FIGS. 9 through 12  are schematic views of shell components from the fifth embodiment to the eighth embodiment of the present invention, respectively. 
         FIG. 13  is a schematic view illustrating a heat-conducting portion in  FIG. 9  contacted by a user&#39;s fingers. 
         FIG. 14  is a schematic view illustrating a heat-conducting portion in  FIG. 12  contacted by a user&#39;s fingers. 
         FIG. 15  is a schematic view of a shell component of the present invention used in a lamp. 
         FIG. 16  is a schematic view of a shell component of the present invention used in a relay unit. 
         FIG. 17  is a schematic view of a shell component of the present invention used in a solar power connection box. 
         FIG. 18  is a schematic view of a shell component of the present invention used in an inverter. 
         FIG. 19  is a schematic view of a shell component of the present invention used in a wearable device. 
         FIG. 20  is an exploded view of the wearable device in  FIG. 19 . 
         FIG. 21  is a sectional view of the wearable device in  FIG. 19 . 
         FIG. 22  is a schematic view of a shell component of the present invention used in a mobile phone. 
         FIG. 23  is a sectional view of the electronic product in  FIG. 22 . 
         FIG. 24  is a sectional view of a middle shell body in  FIG. 22 . 
         FIG. 25  is a sectional view similar to  FIG. 24  illustrating the middle shell body according to another embodiment. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     A biologically temperature-controlled electronics shell component  10  of a first embodiment of the present invention is shown  FIGS. 1 through 4  of the drawings. The biologically temperature-controlled electronics shell component  10  according to the present invention is applicable to electronic products such as mobile phones, tablet devices, laptop computers, WiFi (Wireless-Fidelity) routers, projectors, mini-cameras, LED (Light-emitting diode) lamps, solar power connection boxes, solar inverters and wearable devices (for example, smart watches and Google glasses). In this embodiment, the electronic product is a mobile phone (or a tablet device) and includes a substrate  16  carrying semiconductor components and installed inside a device body of the electronic product (not shown). The substrate  16  is provided with at least one heat source  18  from which radiant heat is generated during activation of the electronic product. 
     The shell component  10  includes an outer shell body  12  and an outer heat-conducting sheet  14 . The outer shell body  12  is combined with the device body of the electronic product and made of a low-thermal-conductivity material such as plastic or glass. The outer shell body  12  includes an inner surface  20  and an outer surface  22  opposite to the inner surface  20 . The outer shell body  12  further includes at least one hole  24  penetrating the inner and outer surfaces  20  and  22 . In this embodiment, the outer shell body  12  includes two spaced holes  24 , and one of the holes  24  corresponds to the heat source  18 . The outer heat-conducting sheet  14  is made of a high-thermal-conductivity material such as metal and combined with the outer shell body  12 . The outer heat-conducting sheet  14  includes opposite inner and outer end faces  26  and  28 . The inner end face  26  of the outer heat-conducting sheet  14  faces or corresponds to the heat source  18  of the electronic product. The outer heat-conducting sheet  14  further includes at least one heat-conducting portion  30  corresponding to the at least one hole  24 . In this embodiment, the outer heat-conducting sheet  14  includes two spaced heat-conducting portions  30 . Each heat-conducting portion  30  is composed of a convex portion protruding outward from the outer end face  28  and is embedded into a corresponding hole  24  in the outer shell body  12 , so that each heat-conducting portion  30  is displayed on the outer surface  22  of the outer shell body  12 , and the periphery edge of the heat-conducting portion  30  is encased in the thickness of the outer shell body  12 . In this embodiment, each heat-conducting portion  30  has an outer side  32  which is flush with the outer surface  22  of the outer shell body  12 , and each heat transfer portion  30  is formed by recessing the inner end face  26  of the outer heat-conducting sheet  14 . In a feasible embodiment, the outer side  32  of each heat-conducting portion  30  protrudes outside the outer surface  22  of the outer shell body  12  (not shown). The outer heat-conducting sheet  14  further includes a periphery  37  which is combined with the outer shell body  12  and surrounds the heat-conducting portion  30  and. 
     In this embodiment, the outer heat-conducting sheet  14  is fitted and encased in the outer shell body  12 . Specifically, the outer shell body  12  is made of plastic, and the outer heat-conducting sheet  14  features a plurality of conic pinholes  36  therein. In manufacture, the outer heat-conducting sheet  14  is first placed inside a mold for manufacturing of the outer shell body  12 . Then, the plurality of pinholes  36  are injected with plastic such that the heat-conducting portions  30  of the outer heat-conducting sheet  14  are embedded in the holes  24  of the outer shell body  12 , and the periphery  37  of the outer heat-conducting sheet  14  is encased in the outer shell body  12  for integral combination. Thus, the periphery  37  of the outer heat-conducting sheet  14  is unitary with and connects the outer shell body  12 . 
     In this embodiment of  FIGS. 5 and 6 , the outer heat-conducting sheet  14  is fused with the inner surface  20  of the outer shell body  12  made of plastic. Specifically, periphery  37  of the outer heat-conducting sheet  14  is provided with a flange  38 , and the outer end face  28  of the outer heat-conducting sheet  14  is provided with a plurality of sharpened convex granules  40 . In manufacture, the outer end face  28  of the outer heat-conducting sheet  14  faces the inner surface  20  of the outer shell body  12 , and the heat-conducting portions  30  are fitted in the holes  24  of the outer shell body  12 . The flange  38  and the convex granules  40  of the outer heat-conducting sheet  14  are melted down in a high-frequency melting process and fused with the outer shell body  12  for integral combination. In a feasible embodiment, the periphery  37  of the outer heat-conducting sheet  14  can extend to a circumference of the inner surface  20  of the outer shell body  12  for an expanded heat absorption/dissipation area. 
       FIGS. 7 and 8  respectively illustrate two feasible embodiments of the shell component  10  of the present invention. In  FIG. 7 , each heat-conducting portion  30  corresponding to the hole  24  is composed of a convex portion protruding outward from the inner end face  26 , so that the heat-conducting portion  30  can be closer to the heat source  18  or even contact the heat source  18 . In  FIG. 8 , each heat-conducting portion  30  corresponding to the hole  24  is composed of a planar portion. In  FIGS. 7 and 8 , the outer heat-conducting sheet  14  is embedded into and encased in the outer shell body  12 , so that the periphery  37  of the outer heat-conducting sheet  14  is wrapped by the outer shell body  12  for integral combination. In a feasible embodiment, the outer heat-conducting sheet  14  in  FIGS. 7 and 8  is fused with the inner surface  20  of the outer shell body  12 . 
       FIGS. 9 through 12  respectively illustrate four feasible embodiments of the shell component  10  of the present invention. The main difference between the four shell components  10  and the shell component  10  in the first embodiment lies in the shape, number, and arrangement positions of the holes  24  and the heat-conducting portions  30 .  FIG. 9  illustrates a longitudinal hole  24  and a transverse hole  24  opened in the upper side and the lower side of the outer shell body  12  for a mobile phone, respectively.  FIG. 10  illustrates a T-shaped hole  24  and a transverse hole  24  opened in the upper side and the lower side of the outer shell body  12  for a mobile phone, respectively.  FIG. 11  illustrates two elliptic holes  24  opened in each side of the outer shell body  12  for a tablet device.  FIG. 12  illustrates a longitudinal hole  24  opened in each side of the outer shell body  12  for a tablet device. When a plurality of holes  24  are designed to be adjacent to sides or the periphery of the outer shell body  12 , a user holing a mobile phone or a tablet device contacts the heat-conducting portions  30  by skin (fingers also) through which radiant heat generated by the heat source  18  is fast conducted. 
     In practice, the shell component  10 , which has the outer heat-conducting sheet  14  being adjacent to (or corresponding to) the heat source  18  and provided with the heat-conducting portions  30  in communication with the corresponding holes  24 , allows radiant heat from the heat source  18  of airtight or semi-tight semiconductor components to be quickly absorbed by the outer heat-conducting sheet  14 , uniformly distributed at other low-temperature airtight regions of electronics, and dissipated at ambient space outside the shell component  10  through the holes  24  fast. Moreover, when a user operates a mobile phone or a tablet device, the user&#39;s fingers holding the mobile phone or the tablet device can contact the heat-conducting portions  30  via the holes  24  ( FIGS. 13 and 14 ), so that the heat-conducting portions  30  and the human body form a heat exchange effect to achieve fast heat conduction and dissipation, thereby preventing or delaying the heating of radiation inside the device body and allowing temperature inside the device body to be slightly higher than human body temperature. Specifically, a temperature rise attributed to the heat source  18  (for example, between 60 and 120° C.) can be reduced to a range from 38 to 40° C. through heat conduction of the heat-conducting portions  30  and biological temperature-control of the human body for normal operations of semiconductor components and controllable temperature inside the device body without damages of batteries due to high temperature. Moreover, the outer heat-conducting sheet  14  of the present invention can be processed for absorption of high radiant heat, fast heat conduction, fast heat dissipation, oxidation resistance, insulation and/or anti-static electricity without negative effects like oxidation and electromagnetic interference common in copper conductor tubes, copper conducting strips, copper-plated graphite rods or copper condenser tubes. 
     The shell component  10  of the present invention prevents semiconductor components inside a device body from high temperature and relies on biological temperature control of the human body for reverse heat conduction to inside of the device body, so that the electronic product kept at low-temperature status can be activated by biological temperature control. Specifically, an ordinary electronic product or a wearable device (for example, smart watch or smart glasses) kept at low-temperature status (below 10° C.) should be deactivated mandatorily for protecting a battery. In practice, the shell component  10  of the present invention allows biological temperature at a user&#39;s skin (fingers also) contacting the heat-conducting portions  30  through the holes  24  to be transmitted to inside of the electronic product for warming, activation and operation. 
       FIG. 15  illustrates the shell component  10  in the ninth embodiment. In this embodiment, the electronic product is an LED lamp  42  which includes a device body  44 , a shell component  10  combined with the device body  44 , a substrate  16  inside the device body  44 , and a plurality of heat sources  18  mounted on the substrate  16 . The shell component  10  includes an outer shell body  12  mounted on the device body  44  and an outer heat-conducting sheet  14  engaged with the outer shell body  12 . The outer shell body  12  has a hole  24  corresponding to the heat sources  18 . The outer heat-conducting sheet  14  includes a heat-conducting portion  30  protruding outward from the outer end face  28 . The heat-conducting portion  30  is embedded into the hole  24  and displayed on the outer surface  22  of the outer shell body  12 . The periphery  37  of the outer heat-conducting sheet  14  is integrally encased in the outer shell body  12 . 
       FIG. 16  illustrates the shell component  10  in the tenth embodiment. In this embodiment, the electronic product is a WiFi relay unit  46  which includes a device body  48  and a shell component  10  combined with the device body  48 . The device body  48  accommodates a substrate  16  on which a plurality of heat sources  18  is mounted. The shell component  10  includes an outer shell body  12  and an outer heat-conducting sheet  14 . The outer shell body  12  is combined with the device body  48  and has a hole  24  corresponding to the heat sources  18 . The outer heat-conducting sheet  14  includes a heat-conducting portion  30  protruding outward from the outer end face  28 . The heat-conducting portion  30  is embedded into the hole  24  and displayed on the outer surface  22  of the outer shell body  12 . 
       FIG. 17  illustrates the shell component  10  in the eleventh embodiment. In this embodiment, the electronic product is a solar power connection box  50  which includes a device body  52 , a shell component  10  combined with the device body  52 , a substrate  16  installed in the device body  52  and a plurality of heat sources  18  on the substrate  16 . The shell component  10  includes an outer shell body  12  and an outer heat-conducting sheet  14 . The outer shell body  12  is combined with the device body  52  and has a hole  24  corresponding to the heat sources  18 . The outer heat-conducting sheet  14  includes a heat-conducting portion  30  protruding outward from the outer end face  28 . The heat-conducting portion  30  is fitted in the hole  24  and displayed on the outer surface  22  of the outer shell body  12 . 
       FIG. 18  illustrates the shell component  10  in the twelfth embodiment. In this embodiment, the electronic product is a solar inverter  54  which includes a device body  56 , a shell component  10  combined with the device body  56 , a substrate  16  installed in the device body  56 , and a heat source  18  on the substrate  16 . The shell component  10  includes an outer shell body  12  and an outer heat-conducting sheet  14 . The outer shell body  12  is combined with the device body  56  and has a hole  24  corresponding to the heat sources  18 . The outer heat-conducting sheet  14  includes a heat-conducting portion  30  protruding outward from the outer end face  28 . The heat-conducting portion  30  is embedded into the hole  24  and displayed on the outer surface  22  of the outer shell body  12 . The periphery  37  of the outer heat-conducting sheet  14  is integrally encased in the outer shell body  12 . 
       FIGS. 19 through 21  illustrate the shell component  10  in the thirteenth embodiment. In this embodiment, the electronic product is a smart watch (wearable device)  58 , which includes a device body  60 , a watch cover  62  engaged on the device body  60 , a shell component  10 , a substrate  16  installed in the device body  60 , and a heat source  18  on the substrate  16 . The shell component  10  includes an outer shell body  12  and an outer heat-conducting sheet  14 . The outer shell body  12  is combined with the device body  60 , and a ring hole  24  is opened in the outer shell body  12  and corresponds to the heat source  18 . The outer heat-conducting sheet  14  includes a heat-conducting portion  30  protruding outward and being adjacent to the periphery  37  of the outer heat-conducting sheet  14 . The heat-conducting portion  30  is embedded into the hole  24  and displayed on the outer surface  22  of the outer shell body  12 . The periphery  37  of the outer heat-conducting sheet  14  is integrally encased in the outer shell body  12 . When the smart watch  58  is worn on a user, the heat-conducting portion  30  contacts the user&#39;s skin through which radiant heat generated by the heat source  18  is fast conducted for effective heat dissipation based on biological temperature control of the human body. 
       FIGS. 22 through 23  illustrate the shell component  10  in the fourteenth embodiment. In this embodiment, the shell component  10  includes an outer shell body  12  combined with a device body of an electronic product, an outer heat-conducting sheet  14  mounted on the outer shell body  12 , a middle shell body  12   a  installed inside the device body of the electronic product, and an inner heat-conducting sheet  14   a  combined with the middle shell body  12   a . The device body of the electronic product (not shown) accommodates a substrate  16  for semiconductor components and at least one heat source  18  on the substrate  16 . The outer shell body  12  and the outer heat-conducting sheet  14  in the fourteenth embodiment are similar to the outer shell body  12  and the outer heat-conducting sheet  14  in  FIG. 3  in structure and not explained hereinafter. The middle shell body  12   a  includes opposite inner and outer surfaces  20  and  22  and a hole  24   a  penetrating the inner and outer surfaces  20  and  22  ( FIG. 24 ) and corresponding to the heat source  18  as well as the outer heat-conducting sheet  14 . The inner heat-conducting sheet  14   a  includes opposite inner and outer end faces  26  and  28  and a heat-conducting portion  30   a  protruding outward from the inner end face  26 . The heat-conducting portion  30   a  is adjacent to or corresponds to the heat source  18 , and the heat-conducting portion  30   a  is embedded into the hole  24   a  of the middle shell body  12   a . In this embodiment, each heat-conducting portion  30   a  is formed by recessing the outer end face  28  of the inner heat-conducting sheet  14   a , and the periphery edge of the heat-conducting portion  30   a  is wrapped in the thickness of the middle shell body  12   a.    
     In practice of the shell component  10  in  FIGS. 22 and 23 , the middle shell body  12   a  and the outer shell body  12  can be used to substitute the middle shell body and the outer shell body of an existing mobile phone directly without any modification inside the existing device body in structure. Moreover, the inner heat-conducting sheet  14   a  being adjacent to or corresponding to the heat source  18  and located between the outer heat-conducting sheet  14  and the heat source  18  quickly absorbs radiant heat generated by the heat source  18  of an airtight or semi-tight semiconductor component, so that heat is uniformly distributed at other low-temperature airtight regions of the electronic product and dissipated at ambient space outside the shell component  10  through the outer heat-conducting sheet  14  for fast conduction of radiant heat from the heat source  18 . Furthermore, the fingers of a user who is operating a mobile phone or a tablet device contact the heat-conducting portions  30  of the outer heat-conducting sheet  14  for effective heat exchanges between the heat-conducting portions  30  and the human body and fast heat conduction and dissipation. 
     In the embodiment of  FIG. 24 , the inner heat-conducting sheet  14   a  is integrally fitted and covered in the middle shell body  12   a  (similar to the fitting and covering structure shown in  FIG. 3 ). In the embodiment of  FIG. 25 , the inner heat-conducting sheet  14   a  is welded and joined to the middle shell body  12   a  to form an integrated structure (similar to the welded structure shown in  FIG. 6 ). 
     The scope of the invention is to be indicated by the appended claims, rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are intended to be embraced therein.