Abstract:
A hinge mechanism for a portable, foldable electronic device comprising two or more positions and comprising at least three housing parts foldable in relation to each other, wherein the hinge mechanism comprises: a hinge system adapted to couple a first housing part to a second housing part, to fold the first and the second housing parts in relation to each other, and to couple the first and the second housing parts to a third housing part in a foldable manner; and an ejector mechanism adapted for moving said hinge system away from the third housing part.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]     This application is a divisional application from U.S. patent application Ser. No. 09/918,283 filed on Jul. 30, 2001. 
     
    
     FIELD OF THE INVENTION  
       [0002]     The present invention relates to a hinge mechanism for a portable, foldable electronic device comprising two or more positions.  
       BACKGROUND OF THE INVENTION  
       [0003]     For storing various 1data, known electronic devices are available, such as notepad computers, small hand-held computers or PDA devices (personal digital assistant). The data can be viewed by means of the display of the device. The data are entered in the devices by means of a keypad or a touch screen. Also wireless communication devices, such as mobile phones, comprise a keypad and a display for storing or selecting telephone numbers. Known devices include Nokia® 8850, 7110 and 6110 mobile phones. Devices are also available having two different user interfaces, normally the user interfaces of a mobile phone and a PDA device. One such known device is Nokia® 9110 Communicator, whose first user interface (opened position) is a PDA user interface and second user interface (closed position) is a CMT user interface (cellular mobile telephone) for mobile phone functions. The device comprises separate keypads and displays for the different user interfaces. The device comprises two housing parts hinged to each other. On their inner side, the PDA user interface of the device is protected between the housing parts in the closed position of the device. The CMT user interface is on the outer side of one housing part.  
         [0004]     A PDA/CMT device comprising two user interfaces and two different use positions is also known from U.S. Pat. No. 6,014,573. In the closed position, the device is used as a mobile phone, and in the opened position, a separate keypad and display are available. When opened, it is also possible to have e.g. a wireless connection to a communication network and to search for information by means of a browser or communication software in the device. A PDA/CMT device comprising two or more foldable housing parts is also known from U.S. Pat. No. 6,047,196. The CMT user interface is placed on the outer sides of both housing parts. One embodiment of the device also comprises a wide display which is divided into two foldable housing parts. A corresponding wide display comprising two foldable housing parts is also known from the patent publication U.S. Pat. No. 5,734,513. When the housing parts are closed, the displays remain protected therebetween. The separate displays are placed next to each other to form a wider uniform display.  
         [0005]     It is known that devices comprising a CMT user interface only can also be provided with auxiliary functions, for example a camera, as disclosed in the application publication EP 0 963 100 A1. Electronic images produced with the camera, for example still images or video images, can be transferred to the display of the device or be transmitted in a wireless manner elsewhere in the communication network and to other CMT devices. A particular problem is induced by the placement of the camera also in the PDA/CMT device to make the use of the camera possible and simple in different positions of the device.  
         [0006]     In known PDA/CMT devices that can be opened and closed, a problem is the placement of keys or corresponding control buttons, cursor keys, rotatable rolls or balls, rocker buttons or navigation keys in an optimal way for the use. A particular problem lies in two interfaces which are used in different positions of the device, wherein the grip of the user&#39;s hand should be simultaneously changed and/or released to make the use comfortable and to make opening of the device even possible. When opening and changing the grip, both hands are often needed. The keys for several different grips must be placed within reach of the fingers, but at the same time, they often require space e.g. on the display. To facilitate each grip, the device comprises several separate keys for the same function. When browsing, wide displays are preferable, wherein they extend even to two housing parts when the devices become smaller. To make the use of the device comfortable, the placement of the keys and the holding positions should be ergonomic. It is problematic to implement control keys for other integrated auxiliary functions and positions in PDA/CMT devices whose size is continuously reduced.  
         [0007]     Other portable foldable electronic devices are shown in EP 0898405 A2, U.S. Pat. No. 5,923,751 and JP 9305259.  
       SUMMARY OF THE INVENTION  
       [0008]     The present invention provides an improvement to the prior art. The present invention facilitates the use of the device by making its handling possible with the grip of one hand both in the opened and in the closed position. The housing parts of the device can be opened without changing the grip or the orientation of the device.  
         [0009]     The hinge mechanism of the device places the housing parts next to each other, and also the total width of the device can be reduced when the housing parts, placed against each other, are moved thereby partly into the handle-like housing part. The displays are protected between the housing parts. The hinge system can be hidden behind the housing parts and inside the handle part, and it comprises a mechanism which automatically opens and preferably also unfolds the device. By means of the hinge system, the point of revolution of the housing parts can be placed right at the edge of the inner walls, facilitating the implementation of various integrated foldable displays.  
         [0010]     Also in the closed position, the PDA/CMT device is held by the handle part, wherein it is also provided with an electronic display, for example for selecting telephone numbers from a list to be scrolled on the display. A telephone number is selected and a call is started and terminated by using control buttons, a navigation key or the like in the handle part. The earpiece of the phone is placed in the upper part of the opening housing part, and the microphone is placed in the lower part.  
         [0011]     The PDA/CMT device is preferably a flat device comprising two designed and substantially parallel side surfaces. A flat side surface is formed by the outer side of one opening housing part as well as the side surface of the handle part, separated by the hinge seam. The opening housing parts, placed against each other, are located on opposite sides of the device, next to the handle part. The handle part and the other housing parts are preferably stationary in relation to each other when the device is in the closed position.  
         [0012]     The device based on a handle-like housing part which is added to foldable housing parts and in which the keys and other control buttons or the like are placed. The invention is based on the way in which the other housing parts are folded in relation to this handle part. The handle part can be designed for an ergonomic grip. When the control buttons are placed on different sides of the handle part, and a navigation key which is preferably also equipped with a push-button function is placed on the upper corner of the device, the device can be controlled with one grip. The device can be opened with a push-button on the top surface. The same keys can also be used to control the auxiliary functions, such as camera, video and music functions. The keys or the like are placed in such a way that the PDA/CMT functions of the device can be used without changing the grip and preferably in the same way by both the left and the right hand.  
         [0013]     A particular advantage is obtained when the aim is to transmit a video image of the user during a call, wherein the closed device can be easily and quickly opened to answer a video call. By means of an image sensor in the device, it is possible to create images in electrical format. The images can be electronically transferred forward and/or displayed on the display of the device. It is not necessary to release the hand from the handle part, wherein the fingers remain on the keys to secure a quick start and control of the functions. The display of the opened device is available for displaying received images e.g. during a video call.  
         [0014]     The lower part of the handle is designed as a crutch. The device remains opened and vertical when placed on a base, for example on a table, and a video call can be continued by releasing the grip, wherein the hands are released for other use. At the same time, the display and the camera are directed to the user. In this position, the display presents, for different purposes, e.g. an electronic calendar, a web site or an electronic still image photographed with a camera as a screensaver or in a way resembling a frame. The handle part also supports the horizontal device in a tilted position, which makes it easier to read the display.  
         [0015]     According to an embodiment, the mechanism for moving the camera changes the orientation of the image sensor automatically when the device is opened. In one case, the image sensor will automatically follow also the user, e.g. by focusing on a detector fixed on the user. The orientation of the camera can also be changed by programming or manually, e.g. by using a 4-directional navigation key in the handle part. The orientation of images, text and other information on the display can be preferably changed in at least two positions rotated 90° in relation to each other. Thus, the opened device can be used in both the vertical and the horizontal position according to the preference of the user or the alternative which is advantageous in view of the application to be run in the device or in view of the information displayed on the display.  
         [0016]     According to an embodiment, the electronic displays located in the two different housing parts are placed adjacent to each other in the opened device, forming a display area which is as seamless and uniform as possible. The display area is slightly folded, but it is preferably substantially planar. This makes it possible to display larger units than one display at one time. Placed on the side of the displays, also adjacent, are also the stereo speakers of the device, for example on both sides of the displays.  
         [0017]     In an embodiment, the upper part of the handle part is provided with the viewfinder of an electronic camera. In the closed device, the image sensor of the camera is oriented in the same direction as the viewfinder. Taking of an electronic image is controlled by control buttons in the handle part. The display of the handle part is also used as the display for the camera.  
         [0018]     In an embodiment, it is also possible to connect to the device a wirelessly operating headset device comprising one or more earpieces and a headset. The device can be used e.g. as a hands-free device. According to another advantageous embodiment, these are also used for listening to music which is transmitted from the PDA/CMT device in digital format in a wireless manner. The music is stored in the memory means of the device and/or it is transmitted to the device by using a wireless communication network. The functions are controlled by using the above-mentioned keys or buttons in the handle part. The headset device can also be equipped with a control unit comprising e.g. a display and keys. According to an advantageous embodiment, the device is controlled in a wireless manner by means of the headset control unit. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0019]     In the following, the invention will be described in more detail by using as an example an electronic PDA/CMT communication device. In this context, reference is made to the appended drawings, in which:  
         [0020]      FIG. 1  shows an electronic device according to an embodiment of the example, particularly a PDA/CMT device in a closed position and seen from the left hand side,  
         [0021]      FIG. 2  shows the device of  FIG. 1  in a closed position and seen from the right hand side,  
         [0022]      FIG. 3  shows the device of  FIG. 1  in a semi-open position in a perspective view, seen from the rear left side and sloping downwards, and  
         [0023]      FIG. 4  shows the device of  FIG. 1  in an open position in a perspective view, seen from the front left side and sloping downwards, and  
         [0024]      FIG. 5  shows the device of  FIG. 1  in an opened horizontal position and seen from the front,  
         [0025]      FIG. 6  shows the device of  FIG. 1  in a closed position and seen from above,  
         [0026]      FIG. 7  shows the hinge mechanism for the device of  FIG. 1 .  
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0027]     With reference to  FIGS. 1 and 2 , a communication device  1 , in the following description also called device  1 , comprises in the use position a horizontal handle-like housing part  2  comprising a substantially even side surface  21 . The housing part  2  is arranged for holding the device  1  in the user&#39;s palm. A side surface  22  with a substantially identical shape is located on the opposite side of the housing part  2 , i.e. the handle part  2 , and the device  1 .  FIG. 2  also illustrates the user&#39;s grip to hold the device  1 . In  FIGS. 1 and 2 , the device  1  is shown in a closed position (CMT use position), but the device  1  is held in a corresponding manner when it is in its opened position (PDA use position), as shown in  FIG. 4 . A right-handed user has the thumb and the other fingers on the sides  22  and  21 , respectively; a left-handed user vice versa. The forefinger is placed on top of the handle  2  when using the navigation key  3 . The handle part  2  also comprises a side surface  23  between the side surfaces  21 ,  22 , placed against the user&#39;s palm. The side surface  23  extends transversely across the palm between the thumb and the other fingers, when the device  1  is held in the use position and in a substantially vertical position. In  FIG. 2 , the side surface  23  and the longitudinal direction of the device  1  are placed substantially parallel to the forefinger. The side surface  23  is supported by the palm, resting on it, when the palm is directed towards the user&#39;s face, sloping upwards. The device  1  is thus horizontal or slightly slanted. The fingers are simultaneously used to support the handle part  2  by pressing the side surfaces  21  and  22 , wherein the swinging of the device  1  is efficiently prevented during the use or the opening.  
         [0028]     To control the functions of the device  1 , the handle part  2  is provided with a set of keys, control buttons, navigation keys or the like within the reach of the fingers. When the device  1  is held as shown in  FIG. 2 , the forefinger extends to the upper surface  24  of the handle part  2  and to the edge  25  where a navigation key  3  is placed. Depending on the design of the device  1 , the key  3  can be placed even entirely on the top surface  24  or the side surface  23 , being placed, however, symmetrically between the sides  21 ,  23  for both hands, but preferably it is in the corner  25 . The control key  4  is placed underneath the thumb, and in a corresponding position on the side  21  there is a control button  5  within the reach of e.g. the forefinger. The device  1  is supported with the fingers from different sides, when the key  4  or  5  is pressed down, and at the same time, the lower part of the palm is supported to the handle part  2 . The buttons  4  and  5  are placed in the upper part  26  of the handle part  2 . For left- and right-handed use, the navigation key  3  is symmetrically located in relation to the side surfaces  21  and  22 . If the buttons  4  and  5  have different functions, it is possible that their functions can be exchanged for different hands by programming and by means of the control system of the device.  
         [0029]     The lower surface  28  of the lower part  27  of the handle part  2  is designed in such a way that the opened device  1  is supported against its base and remains in the vertical position as shown in  FIG. 4 . The device  1  is also supported by the unfolded housing parts  6  and  9 , when the lower part  27  extends downwards substantially on the same level with the housing parts  6  and  9 . The display  8  of the device is thus tilted approximately 10-30° backwards, wherein it is easily readable when the user is sitting at a table. At the same time, the camera to be used during a video call can be better directed towards the user. The mass centre of the device  1  is placed on the front side of the supporting point provided by the lower surface  28 .  
         [0030]     With reference to  FIG. 2 , the device comprises a first housing part  6  comprising an outer wall  61  which is simultaneously the side and outer surface of the device  1 . Part of the outer surface of the device  1  is also formed by the side surface  22 . The side surface  22  and the outer wall  61  constitute a substantially even surface which is divided into two halves separated by a longitudinal seam  7  at the hinge. The housing part  6  is on that side of the handle part  2  which is opposite to the side surface  23 . This side is facing the user in the opened position of the device  1 , as shown in  FIG. 5 , when the planar electronic display  8  is being viewed. On this side there is also a side surface  28 , as shown in  FIG. 4 . In this use position, the palm is facing the viewer, and the handle part  2  is oriented away from the user in a direction which is perpendicular (90° angular difference) to the plane defined by the display  8 . In the presented embodiment, an electronic display  81  placed on the inner wall  62  of the housing part  6  and an electronic display  82  placed on the inner wall  92  of the housing part  9  are substantially parallel, when the device  1  is fully opened, as shown in  FIG. 5 . They are placed as close to each other as possible, to form a uniform planar display area  8 . The displays  81 ,  82  and thereby the housing parts  6 ,  9  move to the opposite position (I position shown in  FIG. 6 ), wherein the angular difference is 0°, and to an adjacent position (T position shown in  FIG. 4 ), wherein the angular difference is even 180°, varying for example between 165° and 180°. The handle part  2  is placed at the hinge at the seam between the housing parts  6 ,  9 . In the opposite position, the housing parts  6 ,  9  are parallel with the handle part  2  (0° angular difference).  
         [0031]     The device  1  comprises a corresponding second housing part  9  comprising an outer wall  91  which simultaneously constitutes the side and outer surface of the device  1 . Part of the outer surface of the device  1  is also formed by the side surface  21 . The side surface  21  and the outer wall  91  constitute a substantially even surface which is divided into two halves separated by a longitudinal seam  10  at the hinge. In the closed position, the inner walls  62 ,  92  are placed against each other, close to and facing each other, wherein the displays  81 ,  92  are simultaneously folded together. The displays  81 ,  82  and the inner walls  62  and  92  are protected between the housing parts  6 ,  9 . Separately, the displays  81 ,  82  are substantially rectangular, and when combined by placing their long edges adjacent to each other, they constitute a foldable, almost quadratic display  8 . In one embodiment, the angular position of at least one of the housing parts in relation to the other housing part can be adjusted, e.g. to an angular difference between 0° and 15°. This makes the use easier in the position of  FIG. 5 , wherein the display  82  represents a QWERTY keyboard and the display  81  displays the text written. Thus at least the display  82  is a touch screen. The device  1  can be readily opened in this angular position, from which it can be moved to the fully opened position shown in  FIG. 5  (0° angular difference). The longitudinal edges of the housing parts  2  and  9  are supported against a base to make it easier to write.  
         [0032]     As shown in  FIG. 2 , the upper part  26  of the handle part  2  is provided with an electronic display  11  which is used in the CMT mode for displaying data and information known from mobile phones. These include e.g. text messages, menus for phone settings, the number of an incoming call, the selected phone number, or a phone number list which is browsed. For the CMT mode, the upper part  63  of the housing part  6  is equipped with a set of openings  12  for the phone earpiece which is placed against the user&#39;s ear. The earpiece is placed inside the housing  6  and arranged for converting electric signals into audible sound. The lower part  64  of the housing part  6  is equipped with a necessary set of openings  13  for a phone microphone which is placed inside the housing part  6  and arranged for converting the user&#39;s speech into an electric signal. The earpiece and the microphone can also be provided in a separate auxiliary device in a wireless radio frequency (RF) or infra-red (IR) connection with the device  1 , wherein the microphone and the earpiece can be easily used also in the opened position and in the PDA mode. In particular, Bluetooth™ wireless technology, which is known as such and is suitable for short-range communication, is applied in the implementation.  
         [0033]     Selections from a menu or a list are made by using the button  4  or  5 . For example, the button  4  corresponds to the SEND button of a phone (starting a call, answering a call), and the button  5  corresponds to the END button of a phone (terminating a call). Alternatively, the menus are browsed and a telephone number is selected with the navigation key  3 , which can be rocked at least forward and backward (corresponding to ARROW UP and ARROW DOWN keys). Thus, the key  3  rocks in the direction of the upper surface  24  and the side surface  23 . To make and/or confirm a selection, the key  3  can also be pressed down by a finger (corresponding to the MENU key of a phone). Text can be written by the key  3  or the like by first selecting the write mode and then browsing the letters. A letter is selected by the button function of the key  3  (alternatively by the key  4  and/or  5 ), as also terminating or sending a text message.  
         [0034]     An advantageous embodiment of the device  1  of  FIG. 2  comprises an optical lense arrangement  14  which extends through the handle part  2  and is the viewfinder of the electronic camera. The viewfinder  14  is arranged at the upper edge of the side surface  22 , and it is oriented away from the user in a direction which is substantially perpendicular to the side surface  21 . Alternatively, the view is displayed on the display  11  which is preferably a liquid crystal display (LCD) known as such. The view can be obtained as an image from the image sensor of the camera, converting the optical image to electric signals. The image sensor is for example a charge coupled device (CCD) known as such. On the basis of the view, the camera is focused to its object to take a still or video image. The image is stored in digital format in the memory means of the device  1 , and it can also be transmitted further in a wireless manner in the CMT and PDA modes. Menus and symbols related to the function of the camera, such as dates and image management, are displayed on the display  11 . The button of the key  3  or the control button  4  (or control button  5 ) is used as a release button, and the menus are controlled e.g. by the key  3 .  
         [0035]     According to an advantageous embodiment, the device  1  is used for listening music stored in digital format in the memory means. Furthermore, music signals can be directed to the separate headset device described above. The necessary memory means as well as the means for controlling the functions are alternatively placed in a separate headset control unit. The electric music signals are transferred by means of the device  1  from a communication network to the control unit. On the inner walls  62 ,  92 , the device  1  is also provided with sets of openings  16 ,  17  for stereo speakers. The speakers are inside the housing parts  6 ,  9 . The music functions can be alternatively controlled in the closed position by means of the display  11  and the keys  3 ,  4  and  5 . If the device  1  comprises several different functional modes, e.g. PDA, CMT, camera and player modes, the default mode is the CMT mode for receiving calls. The display  11  thus displays a menu for selecting the other modes. In each mode, the functions of the keys and the like are determined according to the selected mode. According to the invention, in the different modes, the device  1  can still be used without changing or releasing the grip of one hand, as well as by controlling it with the control buttons  4 ,  5  and the navigation key  3 .  
         [0036]     The buttons  4  and  5  are dome-like film keys which click when pressed down and return up automatically. Preferably, the same film covers both the key  4  (or key  5 ) and the side surface  22  (or side surface  21 ), forming a seamless side surface. The button, designed as a bulge with the size of a fingertip, is placed in a low recess in the side surface. Preferably, also the button function of the key  3  clicks and returns up automatically. The click gives the user a clear feel of operation of the key. For versatile menu functions and for controlling the cursor moving on the display, the key  3  rocks in 2 to 8 different directions (up and down, preferably also left and right in the direction of the side surfaces). Corresponding to each direction or pressing, the key  3  gives a continuous or short electric signal for controlling the device  1 . The key  3  is for example round and fitted in a cradle formed in the handle part  2 . Alternatively, the key  3  is a roll, disc or ball which can be rotated in at least two directions and which also allows pressing down. The rotation axis of the roll is substantially perpendicular to the side surfaces  21 ,  22 .  
         [0037]     To facilitate the use, the device  1  is automatically opened by a button  15  which is fitted in a nest formed on the upper surface  24 , as shown in  FIG. 6 . According to one embodiment, the button  15  is a mechanically operated locking device triggering a spring-actuated hinge mechanism. Thus, the grip does not need to be released, opening by one hand is possible, and the device  1  is quickly opened to the position of  FIG. 4  or  5 , for example for a video call. Thus, the camera is also available, and menus displayed on the touch screen  8  can be browsed by one hand.  
         [0038]     When the device  1  is opened, the housing parts  6 ,  9  first move away from the handle part  2 , in the position of  FIG. 6  upwards, after which they can be opened as shown in  FIG. 3 . In  FIG. 6 , the transfer movement and the intermediate position of the housing parts  6 ,  9  are shown with a broken line A. From  FIGS. 1 and 5 , it is seen that the width of the inner wall  92 , corresponding to the width of the inner wall  62 , is greater than the width of the outer wall  91 , which corresponds to the width of the outer wall  62 . The housing parts  6 ,  9  are moved this difference into the handle part  2 , wherein the total width of the closed device  1  is reduced, in the presented embodiment by about 10%.  FIG. 3  shows side edge  93  placed lower than side edge  91 , and the edge  94  therebetween, as well as an equal edge  20  in the handle part  2 . The edges  94  and  20  are placed against each other and form a narrow seam  10  according to  FIG. 1 . The hinge system on the wall edge  93  is not visible in  FIG. 3 . The housing part  6  is provided with corresponding structures. The housing parts  6 ,  9  are supported against the inner parts of the handle part  2  and against each other, to prevent folding.  
         [0039]     In one embodiment, the housing parts  6 ,  9  are glided out and unfolded by means of force effects of springs under tension. The device is closed by gripping the parts  6  and  9  by one hand, folding them against each other and pressing them inside the handle part  2 . The grip of the other hand still corresponds to that shown in  FIG. 2 . In the closed position, the handle part and the housing parts constitute an integrated locked structure which cannot be bent. In the opened-position, the device  1  remains by itself in the position shown for example in  FIG. 4 .  
         [0040]     According to one embodiment of the  FIGS. 3 and 4 , a camera arm  18  for an image sensor is provided on the surface  29  of the upper part  26  in the handle  2 . The horizontal camera arm  18  is placed between the housing parts  6 ,  9 , and it has a set of openings  19  for the sensor lense arrangement. In the closed position, the sensor is oriented in the same direction as the viewfinder  14 . The camera arm  18  is rotatable around its longitudinal axis downwards and in the opposite direction in a sector of at least 180°. The axis of rotation is substantially perpendicular to the side  29  and the walls  62 ,  92  in the opened position of  FIG. 4 . As the camera arm  18  can also be turned at least 90° upwards as shown in  FIG. 5 , the camera can be directed to a wide area, if the device  1  is supported stationary on its base. The axis of rotation is perpendicular to the sides  21 ,  22 . To the position of  FIG. 5 , the camera arm  18  is bent or placed by means of an arch-like slide rail, at the end of which the camera arm  18  is fixed. Alternatively, the camera arm  18  is placed in the housing part  6 , by the right window  32  and parallel with the wall  62 . The set of openings is thus oriented towards the user in a direction which is substantially perpendicular to the surface  62 , wherein in the closed position, the camera is oriented in the direction of the viewfinder without moving the camera arm. The arm  18  can also be provided with rotation around its longitudinal axis to direct the camera downwards and upwards.  
         [0041]     The camera arm  18  is placed in the position of  FIGS. 1 and 5  preferably automatically by means of an electrical and/or mechanical mechanism. Preferably, the position can also be controlled with the navigation key  3 . An image obtained from the image sensor can be preferably displayed on the display  81  and/or  82 , on the basis of which image the orientation of the camera can be checked. As the orientation of the information displayed on the display  8  can be exchanged, the device  1  can be used in the positions of both  FIG. 4  and  FIG. 5 . In the position of  FIG. 5 , the device  1  has a lower gradient angle, about 60° to 80° slanted backwards.  
         [0042]     The arm  18  is left between the housing parts  6  and  9 , wherein their upper edge, extending to the edge on the side of the handle part  2 , is provided with indentations  30  and  31  of equal shape. They are provided with transparent windows  32 ,  33  which are equipped with recesses  34  and  35 , in which each the arm  18  can be fitted in half. The recesses are on the side of the inner walls  62 ,  92  and constitute a uniform space. In the closed device  1 , the arm  18  is placed in a shield between the windows  32 ,  33  and ready for the camera functions as shown in  FIG. 1 .  
         [0043]      FIG. 7  shows, in more detail, a hinge mechanism  36  for the device  1  according to an advantageous embodiment.  FIG. 7  only shows the fixing of the housing part  6  and one half of the split handle part  2 . The other half of the handle part has an identical shape in mirror image. The mechanism comprises an ejector mechanism  37  for ejecting the housing parts  6 ,  9  and the hinge system out of the handle part  2 , an unfolding mechanism  38  to assist in the opening of the housing parts  6  and  9 , and a hinge system  39  for folding the housing parts  6 ,  9  together and in relation to the handle part  2 .  
         [0044]     The ejector mechanism  37  comprises one or more locking clutches  371  and  372  fitted in the handle part  2 . They keep the housing parts  6 ,  9  stationary in the closed position and form a counter-force for one or more spring means, for example pressure springs  373  and  374 , which continuously tend to move the housing parts  6 ,  9  apart from the handle part  2 . A button  15  is arranged to press the upper clutch  371  (in the upper part of the handle part  2 ) which, by means of rod transmission, also turns the lower clutch  372  (in the lower part of the handle part  2 ). A spring  376  turns the clutches into a locking position.  
         [0045]     The hinge system  39  comprises a hinge beam  391  which is parallel with the longitudinal direction of the handle part  2 . Pushed by the springs  373 ,  374 , a beam  391  glides inside the handle part  2  away from the user&#39;s palm. In the opposite direction, the beam  391  is glided by hand. The movement is limited by pins  392  and  393  whose ends are placed in grooves  40 ,  41  inside the handle part  2 . The grooves are formed in transverse ridges  42  and  43  which are also used as guiding rails and are placed in grooves in the other parts of the mechanism. A hinge beam  394  is fixed at one side to the side wall  65  of the housing part  6 , and it is parallel to the beam  391 . The side surface  65  is placed lower than the parallel side surface  61 . The other side of the beam  394  forms a surface corresponding to the side wall  93  of  FIG. 3  in the housing part  6 . The structure is preferably covered to form a uniform side surface and to hide the hinge system.  
         [0046]     A structure corresponding to the beam  394  can be manufactured and integrated in the part  6 . The hinge system comprises a parallel hinge beam for the housing part  9  (not shown in the figure), corresponding to the beam  394 . The beams  391 ,  394  are provided with grooves  395 ,  396 ,  397  and  398  for the ridges  42 ,  43 , used as glides. The beam  394  does not bend or move in relation to the housing part  6 , and the beam  391  does not bend in relation to the handle part  2 . The beams  391 ,  394  are bent around a joint rotation axis C in such a way that their distance from the rotation axis C remains constant.  
         [0047]     The hinge system  39  comprises at least a glide part  399   a  fixed to the upper part of the beam  391  and a glide part  399   b  fixed to the lower part of the beam  391 , their upper and lower surfaces being equipped with arch-like glide grooves. The glide parts extend towards the parts  6 ,  9 . To the upper part of the beam  394  is fixed a counterpart  399   c  extending towards the part  2  and provided with an arch-like neck gliding in the groove of the glide part  399   a . The glide part  399   b  and a counterpart  399   d , fixed to the lower part of the beam  394 , function pairwise in a corresponding way. The turning points C′ of the glide parts and the counterparts are arranged to be placed on a joint rotation axis C which is at the level of the inner walls  62 ,  92  shown in  FIG. 5  and in the seam  83  when the device  1  is folded up. Thus, the housing parts  6 ,  9  remain attached to each other, and simultaneously also the displays  81 ,  82  are placed adjacent to each other as tightly as possible. The rotation axis C is parallel to the longitudinal axis of the handle part  2 . The opening movement can be limited in such a way that the surface  65  is placed against the ends of the glide parts  399   a ,  399   b . To the upper part of the beam  9  is fixed a counterpart  399   e  extending towards the part  2  and provided with an arch-like neck gliding in the groove of the glide part  399   a . A counterpart  446  fixed to the upper part of the support beam operates in a corresponding manner. The glide part  399   b  and a counterpart  399   f , fixed to the lower part of the hinge beam, function pairwise in a corresponding way. To save space, the pair of counterparts  399   c  and  399   e  as well as the pair of counterparts  399   d  and  399   f  are placed on opposite sides of their glide parts.  
         [0048]     The unfolding mechanism  38  comprises arms  382  and  383  arranged on a joint longitudinal shaft journal  381  and extending towards the parts  6 ,  9 . The pin  381  and the arms  382 ,  383  are allowed to move in the transverse direction, towards the parts  6 ,  9  in relation to the beam  391 . The arms  383  and  382  are fixed to the beam  394  and to the hinge beam of the housing part  9  by means of a hinge pin  385  and a hinge pin  384 , respectively. The parallel rotation axes in the longitudinal direction of the hinge pins  384 ,  385  are placed on opposite sides of the axis C, and each rotation axis on the side of the housing part to which also the hinge pin is fixed. The rotation axes are slightly closer to the part  2  than the axis C. The pin  381  is also provided with a tensioned torsional spring  388  which is continuously effective between the arms  382 ,  383  and tends to turn them around the pin  381  towards each other and to be parallel. Thus, a torque force is simultaneously produced, tending to turn the hinge pins  384 ,  385  towards each other around the rotation axis C. The hinge pins  384 ,  385  are turned so that the direction of their rotation axes is maintained. This, in turn, produces a torque effective on the housing parts  6 ,  9  to make them open when ejected, wherein when they are pushed in, the grooves  395 ,  396  are supported to the ridges  42 ,  43  of the housing part  2 . When turned, the distances between the rotation axis of the hinge pin and the axis C on one hand and between the rotation axis of the hinge pin and the pin  381  on the other hand remain constant, with the result that the position of the pin  381  in relation to the beam and the handle part  2  will vary. Therefore, the pin and the arms are fitted in a movable manner in a nest in the middle part of the beam  391 . Further, the ends of the pin  381  are provided with fitting parts  386  and  387 .  
         [0049]     The electrical components of the PDA/CMT device, such as the circuit boards, the transceiver fitted on a circuit board with its electrical circuits and antenna, as well as the control circuits for controlling the displays and the whole device, are arranged in free spaces left between the housing parts. The keys and the control buttons are in an electrical contact with the control circuits. The operation of the whole device is controlled by a control system operating under a control program stored in the memory means and arranged for controlling the above-described device in a desired manner. The design, manufacture and placement of the necessary components as well as the arrangement of the functions can be selected by anyone skilled in the art according to the requirements at the time. In the selection, it is possible to apply technology and methods known as such. The requirements depend on e.g. the different properties of the device, such as camera or music functions, the capacity of the necessary memory means, the connections to other devices, and the network or networks used for wireless communication, such as a GSM mobile communication network based on a cellular network and/or a short-range RF or IR network. The device with its antenna is arranged to operate in a desired, preferably broadband communication network, e.g. to make the transfer of video calls possible.  
         [0050]     The invention has been described above in an application in connection with an advantageous communication device, to which it is particularly well suited, but on the basis of the description, it is obvious for anyone skilled in the art to apply the invention also in connection with other electronic devices within the scope of the appended claims. The device can naturally be also used with other alternative hand grips and in other positions. The presented grip and use position thus provide an example of a preferred way of holding the device of the invention, wherein the keys of the handle part are placed in such a way that at least this grip and the use of several different functions would be possible and easy.