Patent Publication Number: US-2002013132-A1

Title: Portable electronic apparatus

Description:
FIELD OF THE INVENTION  
       [0001] The present invention relates to a portable electronic apparatus.  
       BACKGROUND TO THE INVENTION  
       [0002] Portable electronic apparatuses are an indispensable feature of modern life. Such devices serve to provide entertainment, e.g. portable radios and portable CD players, computing facilities and communications, e.g. mobile telephones, and indeed combinations of these functions.  
       [0003] No user wishes to be weighed down by their portable electronic apparatuses and there is a strong pressure to reduce the size of such apparatuses. However, this tends to result in the apparatuses becoming insufficiently rugged because of the thinning of the apparatus casings. This leads to an increased risk of damage as the smaller apparatuses are more likely to be placed in a back pocket and inadvertently sat on.  
       SUMMARY OF THE INVENTION  
       [0004] The present invention addresses the above-mentioned problem and provides a way of ruggedising apparatus of any size.  
       [0005] According to the present invention, there is portable electronic apparatus comprising a casing including a skin component formed from a carbon fibre and resin composite material. The composite material need not be exposed and may be hidden behind an outer decorative layer. However, the composite material itself has a pleasing appearance which is appropriate for a consumer product.  
       [0006] The present invention is particularly where the skin component has a plurality of closely spaced apertures, for instance for the keys of a keypad to project through, arranged over a substantial portion thereof. Such an apertured area will be inherently weaker than a similar unapertured area. Thus, an area weakened by apertures may be formed from a carbon fibre and resin composite material while another skin component that is not so weakened may be formed from a plastics resin material conventionally used for such components.  
       [0007] The present invention is applicable to mobile telephones, in which case the carbon fibre and resin composite is used for a front panel. 
     
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
     [0008]FIG. 1 is a front view of a mobile telephone embodying the present invention;  
     [0009]FIG. 2 is an exploded view of the casing of the mobile telephone of FIG. 1;  
     [0010]FIG. 3 is a block diagram of the circuitry of the mobile telephone of FIG. 1; and  
     [0011]FIG. 4 illustrates the moulding process used to produce the main front cover of the mobile telephone of FIG. 1. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
     [0012] An embodiment of the present invention will now be described, by way of example, with reference to the accompanying drawings.  
     [0013] Referring to FIGS. 1 and 2, the casing of a mobile telephone  1  comprises four main skin components  3 ,  4 ,  5 ,  6 . A main front panel  3  is generally elongate and convex when viewed from the front. A small aperture  7  for providing a sound path to a microphone  8  (FIG. 3) is provided centrally at the bottom of the main front panel  3 . Holes  9  for most of the keys of a keypad  10  are arranged above the small aperture  7 . An inverted substantially triangular aperture  11  is located above the holes  9  and receives an escutcheon  4 . The escutcheon  4  has three small holes  13 ,  14 ,  15  around its lower corner through which buttons of the keypad  10  protrude, and a window  19  through which the telephone&#39;s display  21  (FIG. 3) can be viewed.  
     [0014] The main front panel  3  is formed from carbon fibre reinforced resin.  
     [0015] A main rear panel  5  has an rim that matches the rim of the main front panel  3 . The rear panel  5  is concave when viewed from the front of the telephone but is divided into a shallow lower portion  23  and a deeper upper portion  24 . The shallower lower portion  23  is the result of a step the back of the main rear panel  5  for receiving a battery mounted in a battery cover  6 . The main rear panel  5  has a number of small apertures (not shown) for making connections to the battery, external devices, e.g. a battery charger, and a SIM card holder (not shown) located on the back of the main rear panel  5  where it is covered by the battery. A vertical tube  26  projects from the top right corner of the main back panel  22  for mounting an antenna  27 .  
     [0016] In the present embodiment, the escutcheon  4 , the main rear panel  5  and the battery cover  6  are moulded from plastics resin material. However, a stronger mobile telephone can be produced by forming these components from carbon fibre reinforced resin.  
     [0017] Referring to FIG. 3, the circuitry of the mobile telephone  2  is conventional for a digital mobile telephone and comprises an rf subsystem  30  connected to the antenna  27 . The rf subsystem  30  is also connected to a baseband subsystem  31 . The rf and baseband subsystems  30 ,  31  are controlled by a controller  32  which also controls the display  21 . The controller  32  can also read data from and write data to a SIM card via the contacts of a SIM card holder  33  and gets inputs from the keypad  10  The microphone  8  and a loudspeaker  35  are connected to the baseband subsystem for receiving and transmitting audio signals. The mobile telephone  1  also includes power supply circuitry (not shown) from powering the afore-mentioned elements.  
     [0018] Referring to FIG. 4, the main front panel  3  is formed by laying carbon fibre fabric  40 , impregnated with resin, into a mould  41  which defines the outer face of the main front panel  3 . A core  42 , defining the back of the main front panel  3 , is lowered into the mould  41 . The mould  41  and the core  42  are then heated in an autoclave in the conventional manner.  
     [0019] After heating in the autoclave, holes are formed in the front panel blank  44  by a numerically controlled milling machine  45  to produce the finished main front panel  3 .  
     [0020] It will be appreciated that the present invention may be embodied in ways that differ from the exemplary embodiment described above.