Abstract:
A device such as a radiotelephone having a housing within which is located a single printed circuit board and a headset socket  30  including a body and spring contacts  38  which are held in operative contact with the circuit board by retaining means comprising co-operating parts  22, 23, 44  of the housing and the body of the socket.

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates generally to a device, and more specifically, to the way in which a headset socket is mounted within a device, such as a radiotelephone. 
     Devices, such as for example cellular telephones, are sometimes equipped with headsets which provide the user of the telephone with added privacy when using the telephone. The headsets include a jack or plug which is removably inserted into a socket in the telephone. 
     It is common practice in the art to construct a cellular telephone using two circuit boards, a first rigid circuit board bearing the main engine of the telephone and a second flexible circuit board bearing miscellaneous other components, normally including, among others, the speaker, microphone, the display and, notably, in the context of the present invention the headset socket. 
     The market is placing increasing demand on cellular telephone designers to reduce the physical volume of cellular telephones. One approach to physical volume reduction is to do without the second flexible circuit board. 
     SUMMARY OF THE INVENTION 
     With this in mind, the present invention provides a device having a housing within which is located a single printed circuit board and a headset socket including a body and spring contacts which are held in operative contact with the circuit board by retaining means comprising co-operating parts of the housing and the body of the socket. 
     By virtue of these features, the headset socket is mounted in operative contact with the single printed circuit board in a way which is reliable despite the direct forces to which it is subjected by the user during insertion and removal of the plug. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Exemplary embodiments of the invention are hereinafter described with reference to the accompanying drawings, in which: 
     FIG. 1 shows a perspective view of a cellular telephone in accordance with the present invention; 
     FIG. 2 shows a perspective schematic view of the rear casing of the telephone of FIG. 1; 
     FIG. 3 shows a perspective view of the headset socket used in the telephone of FIG. 1; 
     FIG. 4 shows an end view of the headset socket of FIG. 3; 
     FIG. 5 shows a side view of the headset socket of FIG. 3; 
     FIG. 6 shows a plan view of the headset socket of FIG. 3; and 
     FIG. 7 shows a plan view of the headset socket mounting in the rear casing of the telephone. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     A cellular telephone in accordance with the invention is shown in FIG.  1  and is generally designated  10 . The telephone  10  comprises a housing having a front casing  12  and a rear casing  14 . An antenna  15  projects from the top of the rear casing  14 . Within the housing, a single (rigid) printed circuit board  16  is provided. The main engine of the telephone is surface mounted to the circuit board and other ancillary electrical/electronic components are directly connected to it. 
     FIG. 2 shows the rear casing  14  of the telephone  10 . In this drawing, the front casing  12  of the telephone  10  has been completely omitted and an outline of the circuit board  16  is shown in dashed lines displaced from its normal position within the rear casing  14 . The inside of the rear casing  14  may be thought of as being divided into a large first region  18  making up most of the internal area of the casing  14  and a small second region  20  in the vicinity of the antenna  15 . Inside the second region  20 , a pair of spaced rests  22  are provided. Each rest  22  comprises a pair of upstanding fingers  23  defining a generally U-shaped space or recess  23   a  therebetween. The general depth within the rear casing  14  of the first and second regions  18 ,  20  differs to an extent that if the circuit board  16  is placed in position, as indicated by arrows A, it rests on the large region  20  and covers the second region  18  while leaving a small clearance between the free ends of the fingers  23  and the lower surface of the circuit board  16 . 
     The rests  22  are intended to retain in position a headset socket  30 . The socket  30  is shown from various views in FIGS. 3 to  6 . Referring to FIG. 3, the socket  30  comprises a body  32  generally having the shape of a rectangular block. The body  32  includes an aperture  34  formed in its front face  36  for receiving the plug of a headset. The coupling of the headset plug within the socket  30  is conventional and so is not described here further, except to say that this coupling is communicated electrically from the socket  30  to the rest of the telephone by spring fingers  38 . The spring fingers  38  upstand at an acute angle from the upper surface  40  of the body  32 . In FIGS. 3 and 5, the spring fingers  38  are shown in their natural bias position. The spring fingers  38  can be depressed to lie flat against the upper surface  40  of the body  30 . On opposed side surfaces  42  of the body  32 , a pair of retaining protuberances or wings  44  are formed. The retaining wings  44 , as best seen in FIG. 5, are generally U-shaped and adapted to sit within the U-shaped spaces  23   a  defined by each rest  22 . FIG. 7 shows the socket  30  in this position. It will be noted from this drawing that the front face  36  of the body  30  stands flush with the outer surface of the casing  14 . 
     During assembly, the socket  30  is placed into position by a pick-and-place machine. With this in mind, the dimensional tolerances of the retaining wings  44  and the rests  22  are selected to be compatible with the alignment accuracy of this process. Then, the circuit board  16  is fitted within the rear casing  14  as illustrated by arrows A in FIG.  2 . Contact pads  50  on the underside (from the FIG. 2 viewpoint) of the circuit board  16  as shown in dotted outline in FIG. 2 each press against one of the spring fingers  38  to provide the electrical connection of the socket  30  with the circuit board  16 . 
     Referring to FIG. 7, it will be appreciated that during insertion and removal of the plug, the socket  30  is subjected to forces in the y-direction. The socket  30  is substantially prevented from moving in this axis in both directions by virtue of the retaining wings  44  being confined between the fingers  23  of the rests  22 . In this way, the engagement of the retaining wings  44  and the rests  22  bears the forces applied by the user and so these forces need not be borne by means for maintaining electrical contact with the circuit board. It will be noted from FIG. 7 the body  32  of the socket being lodged between the rests  22  is confined in the x-direction too. Because of the above-mentioned dimensional tolerances between the retaining wings  44  and the rests  22 , there can be some play between these co-operating parts. However, because the fingers  38  are sprung and not fixed or joined, for example by solder, to the circuit board, the integrity/reliability of the electrical connection between the fingers  38  and the pads  50  is not impaired. 
     In the above described embodiment, the rear casing and the socket fit together with the socket supplying the male parts, i.e. the retaining wings  44 , and the rear casing supplying the female parts, i.e. the rests  22  within which the retaining wings are held. In other embodiments, the socket may be provided with female parts and the rear casing may be provided with male parts. 
     The invention has been described with specific reference to a radio telephone. However it will be apparent to the reader that the headset socket arrangement described is applicable to any device incorporating a headset socket.