Abstract:
To attain a slide mechanism of a portable terminal device which, having a minimal number of parts and keeping the same function as that of a conventional one, enables a substantial production cost reduction, a mechanism relatively slides a first casing and a second casing in a state that the casings are laid over each other in a vertical direction, and is constituted with: a slide case mounted on either one of the first casing and the second casing; a slider slidably accommodated in the slide case and mounted on the other one of the first casing and the second casing; and a resilient means resiliently disposed between the slider and the slide case. The slide case is formed as an integral structure with a guide groove which extends to both ends in a longitudinal direction with the one end thereof being opened. Additionally the slider has a shape which enables the slider to be inserted into the guide groove in an engaged state from the open end side. Also, the slide case is further provided with a stopper portion preventing the slider from coming off after the slider is inserted into the guide groove.

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to a slide mechanism of a portable terminal device, and this slide mechanism is suitably used when a first casing which constitutes a transmitter section and a second casing which constitutes a receiver section of the portable terminal device such as a cellular phone in particular are slidably coupled to each other. 
   2. Description of the Related Art 
   Currently on the market is a cellular phone, as one type of a portable terminal device, which has a slide mechanism for making, in a state that a first casing being a transmitter section with a keyboard portion and a microphone portion and a second casing being a receiver section with a display portion and a speaker portion are laid over each other, a state that the first casing and the second casing are completely laid over each other with the second casing covering an upper surface of the first casing and a state that the second casing is slid in a longitudinal direction along the first casing so that the upper surface of the first casing is exposed. Such a slide mechanism is publicly known as shown in Japanese Patent Application Laid-open No. 2003-125052. 
   The slide mechanism described in the above document is structured of two slide modules composed of a slide case made of a slide cover and a lock plate which are laid over and fixed, a slider slidably accommodated in the slide case, and a leaf spring which is resiliently disposed between the slider and the slide case. The slide modules are parallelly provided on a lower surface of the second casing, and two mounting pins are protruded from the slider to be fixed with screws on the upper surface of the first casing. 
   The above-described structure requires means for engaging the slide cover and the lock plate, which constitute the slide case, to each other. Consequently, the structure of the slide case becomes complex. Additionally, it is also required to caulk and fix the slide case and the lock plate to each other or to spot-weld them for further intensity. As a result, there exists a problem that a production cost becomes high. 
   SUMMARY OF THE INVENTION 
   In view of the above, it is an object of the present invention to provide a slide mechanism of a portable terminal device which, having a minimal number of parts and keeping the same function as that of a conventional one, enables a substantial production cost reduction. 
   In order to achieve the object stated above, the present invention is a mechanism for relatively sliding a first casing and a second casing in a state that the casings are laid over each other in a vertical direction, and is constituted with: a slide case mounted on either one of the first casing and the second casing; a slider slidably accommodated in the slide case and mounted on the other one of the first casing and the second casing; and a resilient means resiliently disposed between the slider and the slide case. Additionally, the present invention is characterized in that the slide case is formed as an integral structure with a guide groove which extends to both ends in a longitudinal direction with the one end thereof being opened, that the slider has a shape which enables the slider to be inserted into the guide groove in an engaged state from the open end side, and that the slide case is further provided with a stopper portion preventing the slider from coming off after the slider is inserted into the guide groove. 
   Further, the present invention is the mechanism for relatively sliding the first casing and the second casing in the state that the casings are laid over each other in the vertical direction, and is constituted with: the slide case mounted on either one of the first casing and the second casing; the slider slidably accommodated in the slide case and mounted on the other one of the first casing and the second casing; and the resilient means resiliently disposed between the slider and the slide case. Additionally, the present invention is characterized in that the slide case is formed as the integral structure with the guide groove which extends to the both ends in the longitudinal direction with the one end thereof being opened, that the slider has a projecting shape in a cross section which enables the slider to be inserted into the guide groove in the engaged state from the open end side, and that the slide case further provided with the stopper portion preventing the slider from coming off after the slider is inserted into the guide groove. 
   The above-described invention can also be structured such that the slide case is integrally formed by press working and constituted with a base plate portion and the guide groove formed of side plate portions bent from both sides of the base plate portion and hooking portions bent inward from respective free ends of the side plate portions. 
   The above-described invention can also be structured such that the resilient means is structured of one leaf spring with an arched shape and that the slider is provided with projection portions preventing a wobble of the slider at both sides across a top portion of the leaf spring. 
   The above-described invention can also be structured such that the slider is provided with a female screw portion on a part exposed from the guide groove of the slide case. 
   The above-described invention can also be structured such that the stopper portion is formed by bending an end portion of a side plate portion or a hooking portion of the slide case. 
   The above-described invention can also be structured such that the stopper portion is formed of a cut-and-raised piece which is cut and raised from a base plate portion of the slide case. 
   Since the slide case is formed integrally and has a simple structure, a number of parts and a man-hour for assembly are reduced so that a substantial cost reduction is achievable. Additionally, by providing the sliding case with the stopper portion, the slider which is fit into the guide groove can be easily prevented from coming off. Further, by providing the slider with projection portions it becomes possible that only one leaf spring is required to be disposed between the slide case and the slider, and also in this respect, the number of parts is reduced to achieve the cost reduction. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a plan view showing a state that a receiving section and a transmitter section, of a cellular phone as one type of a portable terminal device to which a slide mechanism according to the present invention is applied, are closed; 
       FIG. 2  is a plan view showing a state that the transmitter section and the receiving section are relatively slid, from a state shown in  FIG. 1 ; 
       FIG. 3  is a vertical side view generally showing a state how the slide mechanism is mounted on the portable terminal device in the state shown in  FIG. 1 ; 
       FIG. 4  is a sectional view explaining an inner structure of the slide mechanism according to the present invention and a state how the slide mechanism is mounted on the portable terminal device; 
       FIG. 5  is a plan view of a slide module of the slide mechanism according to the present invention; 
       FIG. 6  is a bottom view of the slide module of the slide mechanism according to the present invention; 
       FIG. 7  is a side view of the slide module of the slide mechanism according to the present invention; 
       FIG. 8  is an enlarged sectional view of a locking projection portion provided on a slide case of the slide module of the slide mechanism according to the present invention; 
       FIG. 9  is an enlarged vertical sectional view showing an inner structure of a slide module part of the slide mechanism according to the present invention; 
       FIG. 10  is an explanatory view showing a state before a slider is set in the slide case; 
       FIG. 11  is an explanatory view showing a state after the slider is set in the slide case; 
       FIG. 12  is an explanatory view of another embodiment, which shows a state before a slider is set in a slide case; 
       FIG. 13  is an explanatory view of the embodiment of  FIG. 12 , which shows a state after the slider is set in the slide case; and 
       FIG. 14  is an explanatory view of still another embodiment of a case that a slider is set in a slide case. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   Hereinafter, a case that an embodiment of the present invention is applied to a cellular phone will be described, but a slide mechanism according to the present invention can also be applied to a portable information terminal such as Zaurus (trademark) for example, a calculator, a pocket computer, a hand-held gaming device, an ashtray, a cover of a case and so forth. 
   Hereinafter, the embodiment of the present invention will be described in detail based on  FIG. 1  to  FIG. 9 . In  FIG. 1  to  FIG. 3  in particular, a reference numeral  2  denotes a transmitter section of the cellular phone  1  as one type of a portable terminal device, and this transmitter section constitutes a first casing. On a front surface of the first casing  2 , a microphone portion  2   a  and a keyboard portion  2   b  are provided. Laid over an upper part of the first casing  2  and mounted slidably in a longitudinal direction by the slide mechanism according to the present invention is a receiver section of the cellular phone  1 . This receiver section constitutes a second casing  3 . On a front surface of the second casing  3 , a speaker portion  3   a , a display device  3   b , and a camera portion  3   c  are provided. Incidentally, a reference numeral  4  denotes an antenna. The antenna  4 , being mounted on the first casing  2  side, can be mounted on the second casing  3  side. 
   Next, a structure of the slide mechanism according to the present invention will be described. On both sides of the upper part of the first casing  2 , as shown in  FIG. 3  in particular, platform portions  2   c ,  2   c  are provided. On both sides of a lower part of the second casing  3 , slide portions  3   d ,  3   d  which are slidably engaged with the platform portions  2   c ,  2   c  are provided. Incidentally, the platform portions  2   c ,  2   c  and the slide portions  3   d ,  3   d  can be omitted, since the slide mechanism according to the present invention has two slide modules as described later. 
   Next, a reference numeral  7  denotes a slide module which constitutes the slide mechanism according to the present invention. The slide module  7  is, as shown in  FIG. 1  to  FIG. 3 , mounted in pairs at an appropriate interval on a lower cover  3   e  of the second casing  3 . The slide module  7  is constituted, as only one of the pairs being shown in  FIG. 4  to  FIG. 9  in particular, with a slide case  5  which is mounted on the lower cover  3   e  of the second casing  3 , a slider  6  which is slidably accommodated in the slide case  5 , and a leaf spring  8  which is resiliently mounted between the slider  6  and the slide case  5 . The slider  6  is mounted via mounting screws  9 ,  9  on an upper cover  2   d  of the first casing  2 . In this way, the slide mechanism according to the present invention is disposed between the first casing  2  and the second casing  3 . 
   Next, the slide case  5  of the embodiment is, as shown in  FIG. 5  to  FIG. 9 , integrally formed by press working a metal plate of stainless steel for example, and given a spring characteristic by quench hardening after press working. The slide case  5  is constituted with a base plate portion  5   a , side plate portions  5   b ,  5   b  which are bent and drooped from both sides of the base plate portion  5   a , hooking portions  5   c ,  5   c  which are formed by bending inward free ends of the side plate portions  5   b ,  5   b , and a locking piece  5   d  and a mounting piece  5   e  which are formed at both ends in a longitudinal direction of the base plate portion  5   a . On the mounting piece  5   e , a mounting hole  5   f  is provided. 
   In this way, in the slide case  5 , a guide groove  10  is formed of the base plate portion  5   a , the respective side plate portions  5   b ,  5   b , and the hooking portions  5   c ,  5   c . At a locking piece  5   d  side of the slide case  5  a catching portion  5   g  which is bent from the base plate portion  5   a  is provided, and on a mounting piece  5   e  side stopper portions  5   h ,  5   h  are formed by bending parts of the hooking portions  5   c ,  5   c  to a base plate portion  5   a  side. Additionally, on both sides in the longitudinal direction of the base plate portion  5   a  of the slide case  5 , locking projection portions  5   i ,  5   i  which are raised by press working are provided. 
   The slider  6  is constituted with a pair of guide pieces  6   a ,  6   a  and a guiding projection portion  6   b  and has a projecting shape in a cross section. As shown in  FIG. 9  in particular, the slider  6  is slidably accommodated by fitting the guide pieces  6   a ,  6   a  in engaging portions  10   a ,  10   a  of the guide groove  10  and fitting the guiding projection portion  6   b  into a groove portion  10   b  of the guide groove  10 . The slider  6  is also formed by press working a metal plate such as stainless steel, and given a spring characteristic by quench hardening after press working. On the respective guide pieces  6   a ,  6   a  of the slider  6 , pairs of projection portions  6   c ,  6   c - 6   c ,  6   c  are provided at appropriate intervals. On the guiding projection portion  6   b  female screw portions  6   d ,  6   d  are formed at an appropriate interval by burring, for example. 
   Between the base plate portion  5   a  of the slide case  5  and an inside top portion of the guiding projection portion  6   b  of the slider  6 , the leaf spring  8  with an arc-shaped cross section is resiliently disposed. In a center of the leaf spring  8  a locking portion  8   a  is provided and both ends of the leaf spring  8  are caught by the female screw portions  6   d ,  6   d.    
   When the above-described slide module  7  is assembled, as shown in  FIG. 10 , before the stopper portions  5   h ,  5   h  of the slide case  5  are bent, the slider  6  and the leaf spring  8  together are fit into the guide groove  10  of the slide case  5  from a direction of an arrow, with the both ends of the leaf spring  8  being caught by the female screw portions  6   d ,  6   d  of the slider  6 . After that, by bending the stopper portions  5   h ,  5   h  to the base plate portion  5   a  side with a jig (not shown), assembly is completed and at the same time the slider  6  is prevented from coming off the slide case  5 . Incidentally, only a single stopper portion  5   h  can be provided instead of the plural stopper portions  5   h ,  5   h.    
   The slide case  5  is mounted on the receiver section  3  side, while the female screw portions  6   d ,  6   d  provided on the guiding projection portion  6   b  of the slider  6  are fixed with mounting screws  9 ,  9  on the first casing  2 . In the embodiment, as shown in  FIG. 1  to  FIG. 3 , the slide mechanism with the pair of slide modules  7  is exemplified, but the present invention is not limited thereto. A single slide module  7  can be used instead of the pair of the slide modules  7 . 
   In a state that the transmitter section  2  which constitutes the first casing and the receiver section  3  which constitutes the second casing are laid over each other as shown in  FIG. 1 , the slider  6  is at a starting position of the slide case  5  as indicated with solid lines in  FIG. 4 . At this time the locking portion  8   a  of the leaf spring  8  is engaged with the locking projection portion  5   i  and an end of the slider  6  abuts the stopper portions  5   h ,  5   h , so that the slider  6  is locked in a closed state shown in  FIG. 1 . 
   Next, when the receiver section  3  is pushed in a direction of the antenna  4  in order for operating the keyboard portion  2   b  of the receiver section  2 , the locking portion  8   a  of the leaf spring  8  is disengaged from the locking projection portion  5   i . Then the slider  6  is guided along the guide groove  10  of the slide case  5 , so that the receiver section  3  can slide in the direction of the antenna  4 . Consequently, as shown in  FIG. 2 , the keyboard portion  2   b  on the transmitter section  2  is exposed so as to be able to be operated. 
   When the slider  6  slides in the slide case  5 , the locking portion  8   a  of the leaf spring  8  pressure-contacts on the base plate portion  5   a , so that sliding is conducted in a free stop way. At the same time, the projection portions  6   c ,  6   c - 6   c ,  6   c  of the guide pieces  6   a ,  6   a  of the slider  6  contact on the base plate portion  5   a . Therefore, a vertical swing of the slider  6  by the leaf spring  8  pressure-contacting on the base plate portion  5   a  at a time of sliding of the slider  6  is prevented. 
   The receiver section  3 , sliding on an upper surface of the transmitter section  2 , completely exposes the keyboard portion  2   b  of the transmitter section  2 . Then an end of the slider  6  abuts the catching portion  5   g  of the slide case  5  to stop the receiver section  3 . At this time the locking portion  8   a  of the leaf spring  8  climbs over the locking projection portion  5   i  provided on the base plate portion  5   a  and is engaged therewith, so that the slider  6  is locked at this position. 
   When the receiver section  3  is to return to an original position, the receiver section  3  is pushed in an opposite direction from the direction described above. Then the locking portion  8   a  of the leaf spring  8  is disengaged from the locking projection portion  5   i , allowing the slider  6  to slide. When the end of the slider  6  abuts the stopper portions  5   h ,  5   h , the slider  6  stops. At this time, the locking portion  8   a  of the leaf spring  8  is engaged with the locking projection portion  5   i  of the base plate portion  5   a , so that the slider  6  is locked. In this way, the receiver section  3  returns to the original position as shown in  FIG. 1 . Incidentally, though an example of a single leaf spring  8  is described above, it is also possible that two leaf springs are used and the projection portions  6   c  of the slider  6  are omitted. 
     FIG. 12  and  FIG. 13  show another embodiment of stopper portions of a slider, which are provided on a slide case. According to the drawings, as shown in  FIG. 12 , on a free end side of the slide case  15  stopper portions  15   b ,  15   b  are formed at tips of side plate portions  15   a ,  15   a , and as shown in  FIG. 13  after a slider  6  is fit into a slide case  15  the stopper portions  15   b ,  15   b  are bent inward with a jig (not shown) to prevent the slider  6  from coming off the slide case  15 . Incidentally, the stopper portion  15   b  can be provided on only one of the side plate portions  15   a.    
     FIG. 14  shows still another embodiment of stopper portions of a slider, which are provided on a slide case. According to the drawing, on a base plate portion  20   a  of a slide case  20 , stopper portions  20   b ,  20   b  which are formed of cut-and-raised pieces with resilience are provided. When a slider  6  is fit into the slide case  20 , the stopper portions  20   b ,  20   b  are bent and allow the slider  6  to be fit into the slide case  20  and subsequently returns to an original position to be the stopper portions. In this way, the stopper portions  20   b ,  20   b  prevents the slider  6  from coming off the slide case  20 . Incidentally, a single stopper portion  20   b  can be formed instead of two. Also, it is possible that the piece is raised with a jig and made into a stopper portion after the slider  6  is fit into. 
   In the above embodiments, the slide case S is mounted on the second casing  3  and the slider  6  is mounted on the first casing  2 . However, the slide case  5  can be mounted on the first casing  2  and the slider  6  can be mounted on the second casing  3 . 
   As described in detail above, the slide mechanism according to the present invention has a small number of parts and can be produced at low cost, and therefore is suitably used for a cellular phone in particular among slide-type portable terminal devices.