Abstract:
A handset holder, such as a handsfree car kit, is disclosed. The car kit comprises a cradle ( 21 ) for carrying the handset and a cradle release mechanism ( 22 ) for releasably attaching the cradle ( 21 ) to a mount ( 23 ) fixed, for example to a vehicle dashboard. The holder comprises locating means comprising a tongue and groove for guiding the tongue to a position where the cradle and mount become latched.

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to handset holders. In particular, it relates to the mounting of a handset cradle on a surface, such as the mounting of a car cradle on a vehicle dashboard. 
     Handsfree car kits for handsets such as mobile telephone handsets have been developed, which provide connection of the handset with an external antenna to improve the reception of a call. 
     In one type of car kit, the cradle is fixed to the mount. If the user wishes to take a call privately, as opposed to in handsfree mode, he removes the handset from the cradle. However, by doing this he sacrifices the connection to the external antenna. 
     Another car kit is the Nokia CARK-1, in which the cradle is magnetically coupled to the mount. This car kit is shown in FIG. 1 of the accompanying drawings. In this case, if the user wishes to take a call privately, as opposed to in handsfree mode, he picks up the cradle and handset and removes it from the vicinity of the mount. The external antenna connection is maintained. However, the cradle and mount might come apart if there is a sudden movement of the vehicle, for example by heavy braking or during an accident. If so, this may result in damage to the phone and also injury to the user. Also, the mechanism of this car kit has a large number of parts which complicates its assembly and increases manufacturing time and costs. 
     SUMMARY OF THE INVENTION 
     According to the present invention there is provided a handset holder comprising a cradle for carrying the handset, a mount for attachment to a support surface, and locating means for facilitating the removable coupling of the cradle and the mount, the locating means comprising a tongue and groove for guiding the tongue to a position where the cradle and mount become latched. Such a handset holder maintains the external antenna connection when the handset is in private mode (i.e. removed from the mount). Also, the mechanism is simple and uses few parts and yet the coupling of the cradle and mount is easy for the user. The provision of the tongue and groove significantly reduces the probability of the accidental dismounting of the cradle from the mount. 
     Preferably, the tongue and groove have a wide end and a narrow end, and the tongue is insertable into the groove from a position at the wide end to a position towards the narrow end where the cradle and mount become latched. This enables the user to readily couple the cradle and the mount without having to accurately align them to effect latching. 
     The locating means may comprise a resilient member for carrying a latch bar and preferably this resilient member and latch bar are an integral part of the housing of either the cradle or the mount. Preferably the locating means also comprises a hole in the tongue for receiving the latch bar. This arrangement enables latching of the mount and cradle using a minimum number of components. 
     In a preferred embodiment, the latch bar extends into the groove near its narrow end and the wall of the hole and co-operating surface of the latch bar have sloped surfaces. Such an arrangement gives a tactile indication to the user that the latch bar and hole are aligned and, for example, enables the user to push the cradle down to click it into place and thus be sure that it is latched with the mount. 
     The handset holder comprises user actuable means for facilitating the removal of the cradle from the mount. Preferably these means comprise a lever which acts on the resilient member to remove the latch bar from the hole and thus enable unlatching of the cradle and mount. This lever may be rotated to act on a resilient member by the user actuating a button. Preferably the lever has a sloped or ramped up cam surface which co-operates with the surface of the resilient member. This enables gentle latching and unlatching movement to be achieved, especially if the co-operating surface of the resilient member is also sloped or ramped up. 
     In a preferred embodiment, two buttons and levers are provided and the buttons each also have an associated arm with teeth. When the buttons are pressed the teeth of one arm are meshed with those on the other. This provides reliable synchronised button movement and further reduces component count as no spring is needed to return the buttons into their non-actuated state. The provision of opposing buttons on each side of the cradle or mount facilitates easy removal of the cradle from the mount by the user. 
     Preferably the cradle comprises the tongue and the mount comprises the groove, as this reduces the number of parts on the car cradle. Also, by having the buttons on the mount the phone can be removed using one hand. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Embodiments of the present invention will now be described by way of example, with reference to the accompanying drawings, of which: 
     FIG. 1 shows a known handsfree car kit; 
     FIG. 2 illustrates a cradle, a release mount, and mount fixing according to an embodiment of the present invention; 
     FIG. 3 is an exploded view of the cradle release mount; 
     FIG. 4 is an exploded view of the cradle; 
     FIG. 5 shows front and rear views of the cradle release mount; 
     FIG. 6 shows one type of latching operation according to an embodiment of the present invention; and 
     FIG. 7 shows an alternative latching operation according to another embodiment of the present invention. 
     FIGS. 2 to  5  illustrate a handset holder according to a preferred embodiment of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     FIG. 2 shows a cradle  21  for carrying a handset, a cradle release mount  22  for release of the coupling to the cradle  21  and a mount fixing  23 , which in this case is a swivel mount, for fixing the cradle release mount  22  to a surface such as a car dash. In this arrangement, if the user wishes to take a call using handsfree mode, then he leaves the cradle in the mount. However, if he wishes to take the call privately, he removes the cradle carrying the handset from the cradle release mount  22 . 
     FIG. 3 shows an exploded view of the cradle release mount  22 . This cradle release mount  22  comprises a front cover  31 , a rear cover  32 , left and right buttons, referenced  33  and  34  respectively, for the user to press to release the cradle from this cradle release mount, and a U part  35 . It also comprises an eject spring  36  for assisting release of the cradle from the mount, and a magnet module  37 . This magnet module  37  is, for example, part of a reed relay switch for determining whether the cradle is in the mount. If so, the handsfree unit is switched to handsfree mode, and if not into private mode. 
     FIG. 5 a  shows the front view of this cradle release mount  22  and FIG. 5 b  shows its rear view. These figures show in more detail, the provision of latch bar  52  on a resilient member  51 , both being formed as part of the front cover  31 . They also show in more detail mechanisms relating to the user actuable buttons  33 ,  34  which assist in actuating the release of the cradle  21  from the cradle release mount  22 . Each button has an associated lever  54  with a sloped or ramped up cam surface and an arm  55  with teeth  56 . 
     The U part  35  snap fits onto the front of the mount by latching into holes  55 . This U part  35  provides a groove for receiving a tongue  48  of the cradle. 
     FIG. 4 shows an exploded view of the cradle  21 . The cradle  21  comprises front and rear covers, referenced  41  and  42  respectively, a base cover  47 , and rubber side portions  44  which assist gripping by the user. The cradle  21  also comprises an antenna coupler  43  for coupling the antenna of the handset in the cradle to an external antenna without physically contacting the antenna of the handset in the cradle  21 . A system connector  45  is provided for connecting power etc. to the handset, and a clip mechanism  46  is provided for latching the handset and the cradle. The rear cover  42  of the cradle in this embodiment comprises the tongue  48  having a latch hole  49 . 
     Attachment of the cradle  21  to the cradle release mount  22  will now be described referring to FIG.  6 . 
     To attach the cradle  21  to the cradle release mount  22 , the user first abuts the rear of the cradle to the front of the cradle release mount, and then lowers the cradle. The tongue  48  of the cradle is inserted into the groove of the cradle release mount defined by the front cover of the cradle release mount and the U part  35 . Because the tongue and groove have a wide end and a narrow end, the arrangement provides self-alignment of the latch bar  52  and the latch hole  49  (see FIG. 6 a ). 
     The resilient member  51  of the cradle release mount  22  is biased towards the U part  35 , so that the latch bar  52  extends naturally into the groove. As the cradle moves downwards, the end of the tongue  49  pushes against the surface  62  of the latch bar  52 , causing the resilient member  48  to deform, and so removing the latch bar  52  from the path of the tongue  48 . (See FIG. 6 b ). 
     Once the user has pushed the tongue  48  into the groove to the extent that the latch bar  52  and the latch hole  49  are aligned, the resilient member  51  returns to its natural bias position and the latch bar  52  fits snugly in the latch hole  49 . Consequently, the cradle and cradle release mount are latched. (See FIG. 6 c ). 
     In this embodiment the latch hole  49  is positioned towards the bottom of the tongue  48  so that it can be slid into the groove with little or no force applied to it by the user, until the narrow end of the tongue contacts the portion of the latch bar in its path. Then the user must apply force to cause deformation of the resilient member, so that the cradle clicks into place. This gives a tactile indication to the user that latching has occurred. 
     Unlatching the cradle from the mount is provided by deforming the resilient member  51 , so that the latch bar  52  is removed from the latch hole  49 . It is then retained in a deformed position whilst the tongue is in contact with the latch bar. Once free of the latch bar, the tongue is removed from the groove and the resilient member returns to its natural bias position. Sloping surfaces  61 ,  62  of the latch bar and latch hole provide smooth unlatching. 
     The resilient member  51  is deformed to enable unlatching to occur in response to the user actuating the buttons  33  and  34  of the cradle release mount. The pressing of these buttons results in the rotation of their associated levers  53  and arms  55 . When the buttons are pressed, the associated levers rotate to a position between the front cover of the mount and resilient member, causing the resilient member to deform and move away from the U part, and thus withdrawing the latch bar from the latch hole. In this embodiment, the levers and the portions of the resilient member in their rotational path have ramped up (sloped) cam surfaces to provide smooth movement of the resilient member. As mentioned above, the pressing of the buttons also causes rotation of their respective arms  55  and results in the meshing of the teeth  56  as shown in FIG.  3 . This gear matching provides reliable synchronised button movement. 
     There are many equivalent mechanisms which would provide the latching function. For example, an arrangement is shown in FIG. 7 in which the tongue is provided with a spring-loaded latching bar  71  which is extended in its natural bias position as shown in FIG. 7 a . In this example, the cradle release mount comprises a latch hole  72 . As the tongue is lowered, the spring is deformed due to the latch bar making contact with the wall of the cradle release mount as shown in FIG. 7 b , and only returns to its natural position when the latch bar and the hole are aligned as shown in FIG. 7 c . Similarly, unlatching occurs by the user pulling the cradle upwards so that the spring is deformed by the contact of the latch bar with the wall of the cradle release mount. 
     Other embodiments can also be envisaged. For example, the tongue could appear on the cradle release mechanism and the groove on the cradle. Also, the user actuable means may be provided on the cradle 
     Furthermore, the user actuable means may comprise a slide button or buttons, for example, as opposed to the shown push buttons. 
     In view of the foregoing description, it would be evident to a person skilled in the art that various other modifications may be made within the scope of the claims.