Abstract:
A hinge for portable terminal comprising a first member having a keyboard portion and a second member having a display portion coupled to each other in a manner capable of opening/closing in a vertical direction and rotating in a horizontal direction at a predetermined open angle in the vertical direction. The second member is configured to rotate around a first hinge shaft accompanying an opening/closing operation of the second member relative to the first member in the vertical direction. A second hinge shaft is configured to couple the first and second members to one another in a manner capable of rotating the members in the horizontal direction. The second member is mounted to the second hinge shaft, and the first and second hinge shafts are crossed and engaged with each other at escape recessed portions mounted on each of the hinge shafts.

Description:
FIELD AND BACKGROUND OF THE INVENTION 
     The present invention relates to a hinge for portable terminal suitable for use in portable terminals such as a cellular phone, a small-sized office automation device, and the like. 
     DESCRIPTION OF THE RELATED ART 
     Regarding cellular phones among other portable terminals, for the reasons of portability, protection of a keyboard surface, prevention of malfunctions, and the like, two-fold types in which a transmitter section that is a first member and a receiver section that is a second member are coupled together to each other via a hinge are becoming the mainstream. Also, in recent years, various functions (camera function for example) are added to cellular phones, so that, along with such addition, functions expected from an opening/closing hinge are complicated as well. 
     In such a situation, a hinge constructed such that a transmitter section and a receiver section can be opened/closed using two shafts and further the receiver section can rotate about the shaft in a horizontal direction in a state that the receiver section is opened with respect to the transmitter section is publicly known from an invention disclosed in Japanese Patent Application Laid-open No. 2003-133764. 
     Although the hinge described in the laid-open patent application uses two shafts, these shafts are not crossed to interfere with each other. Thus, there has been a problem that a force to pull the receiver section away from the transmitter section in an up and down direction is generated at the time of opening/closing, which causes positional displacement in a left and right direction to cause a malfunction. Further, the conventionally known one has problems such that it is difficult to produce strength in the hinge, and that the sense of operation is monotonous since opening/closing operations in the opening direction and the closing direction are the same. 
     SUMMARY OF THE INVENTION 
     An object of the present invention is to provide a hinge for portable terminal capable of preventing occurrence of positional displacement of respective component members to preclude malfunctions and moreover performing a different operation at the time of performing an opening operation and a closing operation. 
     Incidentally, although a case of embodying the present invention in a cellular phone will be described below, it is needless to mention that the present invention can be embodied in other portable terminals of two-fold type such as a small-sized office automation device. 
     In order to achieve the above described object, the present invention provides a hinge for portable terminal coupling a first member having a keyboard portion and second member having a display portion of a portable terminal of two-fold type to each other in a manner capable of opening/closing in a vertical direction and capable of rotating in a horizontal direction at a predetermined open angle, and the hinge is characterized by including a cylindrical case cover having a partition wall in a center portion thereof; a first hinge shaft which passes through the partition wall of the case cover and extends in an axial core direction of the case cover so as to be restricted from moving in an axial direction and so as to allow the case cover to rotate around an axis thereof, and which has a first escape recessed portion provided in a portion thereof passing through the partition wall; a case in which the first hinge shaft passes through in an axial core portion thereof in the axial direction and which is fixed to a free end side of the first hinge shaft; a vertical rotation control means, which is provided between the case and the case cover and constituted of a first cam mechanism, for controlling vertical rotation of the case cover; a second hinge shaft having a second escape recessed portion and rotatably attached to the partition wall, with the second escape portion being in contact with and crossing the first escape recessed portion of the first hinge shaft; a mounting member which has a mounting cylindrical portion and a mounting piece attached to the second member and is provided on a free end side of the second hinge shaft to be rotatable at a predetermined horizontal rotation angle, the second hinge shaft passing through the mounting cylindrical portion in an axial direction, said mounting member being restricted from disengaging so as to rotate together with the second hinge pin, and one end side of the mounting member abutting on the case cover; and, a horizontal rotation control means, which is provided between the mounting member and said case cover and constituted of a second cam mechanism, for controlling horizontal rotation of the case cover, further the hinge is characterized by that one end of said case cover is rotatably supported by one of attaching portions provided on both sides of an end portion of the first member, said case is inserted and fitted in a mounting portion provided in the other attaching portion of the first member, said mounting member is fixed to the second member, and the first hinge shaft and the second hinge shaft have the escape recessed portions in a portion where the said first hinge shaft and said second hinge shaft are in contact with each other and cross each other, so that from a closing state to a predetermined open angle of the first member and the second member, the first hinge shaft engages with the escape recessed portion of the second hinge shaft to restrain the rotation of the second hinge shaft, and at the predetermine open angle, the escape recessed portion of the second hinge shaft is at a position facing the escape recessed portion of the first hinge shaft to allow the second hinge shaft to rotate. 
     Further, the present invention provides a hinge for portable terminal coupling a first member having a keyboard portion and second member having a display portion of a portable terminal of two-fold type to each other in a manner capable of opening/closing in a vertical direction and capable of rotating in a horizontal direction at a predetermined open angle, and the hinge is characterized by including: an inner cam having a cam portion on an end portion thereof and arranged in the case cover with the first hinge shaft being inserted through a center portion thereof in the axial direction in a slidable and rotatable manner; a flange portion provided in the first hinge shaft to limit the axial direction sliding of the inner cam up to a predetermined position; an outer cam accommodating the inner cam inside in a manner rotatable at a predetermined rotation angle and slidable in the axial direction, the outer cam being accommodated in the case cover in a state being restrained from rotating and having a cam portion on an end portion thereof in the same direction as the cam portion of said inner cam; a guide plate provided on the partition wall side of said case cover to be engaged with said outer cam, with said first hinge shaft being inserted in an axial core portion thereof in the axial direction; a spring resiliently provided between said inner cam and said guide plate in a state being wound on the first hinge shaft to bias the inner cam to rotate in one direction and to slide in one direction; a cam follower in which the first hinge shaft is inserted through an axial core portion thereof in the axial direction and a cam portion is provided on a side corresponding to the inner cam accommodated in said cover in a slidable manner in one direction; and a compression spring which biases said cam follower to slide in a direction of the inner cam and the outer cam. 
     Further, in the hinge according to the present invention, may include a horizontal rotation control means including: a first cam for swiveling of a base cam, in which said second hinge shaft is inserted through a center portion thereof in the axial direction in a rotatable manner, provided on said case cover side; a second cam for swiveling of a rotary cam, in which said second hinge shaft is inserted through a center portion thereof in the axial direction in a slidable manner, attached on the second member; and a compression spring wound on said second hinge shaft to push the second cam for swiveling toward said first cam for swiveling. 
     Further, in the hinge according to the present invention, the case cover may have a conducting wire guiding portion formed therein in which a conducting wire connecting the first member and the second member is passed through. 
     Since the second hinge shaft to which the second member is attached is crossed and engaged with the first hinge shaft and is constructed to be capable of rotating only at a predetermined rotation angle of the first hinge shaft, it is possible to prevent displacement of the second hinge shaft and the first hinge shaft in the axial direction even when the first member and the second member are repeatedly opened and closed, so that the positional displacement does not occur and malfunctions can be prevented. Moreover, when the first member and the second member are opened/closed, the cam portion of the cam follower is in pressure contact with the respective cam portions of the inner cam and the outer cam which are overlapping with each other, so that an advantage can be achieved that the opening operation and the closing operation can be varied to provide opening/closing operations with different senses of operations respectively. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view showing a cellular phone of two-fold type that is open in which a hinge for portable terminal according to the present invention is embodied; 
         FIG. 2  is an explanatory view showing an attaching state of the hinge for portable terminal according to the present invention from a planar angle; 
         FIG. 3  is a left side view of the hinge for portable terminal according to the present invention; 
         FIG. 4  is a right side view of the hinge for portable terminal according to the present invention; 
         FIG. 5  is a front cross-sectional view showing the inner structure of the hinge for portable terminal according to the present invention; 
         FIG. 6  is a cross-sectional view taken along the A—A line in  FIG. 1 ; 
         FIG. 7  is a cross-sectional view showing a receiver section opened at 90° with respect to a transmitter section from a state in  FIG. 6 ; 
         FIG. 8  is a partial cross-sectional exploded view of the hinge for portable terminal according to the present invention; 
         FIG. 9  is a left side view of a case cover; 
         FIG. 10  is a front view of the case cover; 
         FIG. 11  is a right side view of a guide plate; 
         FIG. 12  is a right side view of an inner cam; 
         FIG. 13  is a right side view of an outer cam; 
         FIG. 14  is a right side view of a cam follower; 
         FIG. 15  is a right side view of a cover; 
         FIG. 16  is a plan view of a first hinge shaft; 
         FIG. 17  is a side view of a second hinge shaft; 
         FIG. 18  is a rear view of a mounting member; 
         FIG. 19  is a plan view of a base cam; 
         FIG. 20  is a rear view of a rotary cam; 
         FIG. 21  is an explanatory view for explaining operations of a first cam portion, second cam portion, and third cam portion; 
         FIG. 22  is an explanatory view for explaining operations of the first cam portion, second cam portion, and third cam portion; 
         FIG. 23  is an explanatory view for explaining operations of the first cam portion, second cam portion, and third cam portion; 
         FIG. 24  is an explanatory view for explaining operations of the first cam portion, second cam portion, and third cam portion; 
         FIG. 25  is an explanatory view for explaining operations of the first cam portion, second cam portion, and third cam portion; 
         FIG. 26  is a side view showing the cellular phone using the hinge for portable terminal according to the present invention in a state that the receiver section is folded with respect to the transmitter section; 
         FIG. 27  is a side view showing the receiver section opened at 150° with respect to the transmitter section; 
         FIG. 28  is a side view showing the receiver section closed up to 90° from the state shown in  FIG. 27  with respect to the transmitter section; and 
         FIG. 29  is a side view showing the receiver section rotated at 90° in a horizontal direction from the state in  FIG. 28 . 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Hereinafter, an embodiment of the present invention will be described based on the drawings. 
     In  FIG. 1 , the reference numeral  1  denotes a transmitter section constituting a first member of a cellular phone A of two-fold type, and on its top surface side, a keyboard  1   a  and a microphone  1   b  are provided. The reference numeral  2  denotes a receiver section constituting a second member, and on a side thereof facing the keyboard side when it is closed, a display portion  2   a , a speaker  2   b , and a camera  2   c  are provided. 
     A hinge B according to the present invention is, as shown particularly in  FIG. 1 , attached between attaching portions  1   c ,  1   d  for coupling the transmitter section  1 , and the structure thereof is shown in  FIG. 2  to  FIG. 20 . 
       FIG. 5  shows a cylindrical case whose one end is open. As shown particularly in  FIG. 8  and  FIG. 15 , this case  3  has recessed locking grooves  3   a ,  3   a  formed on its outer periphery in the axial direction, and is inserted into an insertion hole  1   e  formed on the attaching portion  1   c  of the transmitter section  1  in the axial direction and fixed to the attaching portion  1   c  by engaging projecting locking portions  1   f ,  1   f  formed inside this insertion hole  1   e  with the recessed locking grooves  3   a ,  3   a , as shown particularly in  FIG. 2  and  FIG. 3 . 
     This case  3  further has, as shown particularly in  FIG. 5  and  FIG. 15 , a side wall  3   d  on its one end portion, and in the inside of the case  3 , an attaching portion  4   a  which has a D shape on its cross-section and is formed on an end portion of the first hinge shaft  4  as shown in  FIG. 16 , is inserted into and engaged with a locking hole  3   e  having a D shape formed in the center portion of the side wall  3   d  in the axial direction. 
     The first hinge shaft  4  has, as shown in  FIG. 5  and  FIG. 16 , a first circumferential groove  4   b  on the side of the case  3  in which the locking hole  3   e  is formed, and an E ring  5  is fitted into this first circumferential groove  4   b  as shown in  FIG. 5 , so that the case  3  is locked to be prevented from disengaging. The first hinge shaft  4  further penetrates the center portion of the case  3  in the axial direction, and its one end portion side penetrates a bearing hole  6   b  formed in a partition wall  6   a  of a case cover  6  in the axial direction, which is inserted into and pivotally supported inside a cavity portion  1   g  formed in the attaching portion  1   d . The first hinge shaft  4  thus engages the case cover  6 , and is pivotally supports the case cover  6  via a washer  7  and a push nut  8  to be rotatable. 
     On this case cover  6 , as shown particularly in  FIG. 6  and  FIG. 7 , a thrust bearing hole  6   c  is formed on a position slightly displaced in a direction orthogonal to the bearing hole  6   b , and a pin hole  6   d  is formed in parallel and out of alignment with this thrust bearing hole  6   c . Into the thrust bearing hole  6   c , a second hinge shaft  9  is inserted, and a circumferential groove  9   a  formed on an inserting end side thereof is engaged with a pin  10  pressed into the pin hole  6   d  to thereby prevent disengagement. The second hinge shaft  9  and the first hinge shaft  4  interfere with each other by coming into contact and crossing with each other. A first escape recessed portion  4   c  and a second escape recessed portion  9   b  are provided on this crossing portion so that the second hinge shaft  9  is constructed to be able to rotate in a horizontal direction when the first hinge shaft  4  is rotated at a predetermined angle (90° in this embodiment) and the second escape recessed portion  9   b  of the second hinge shaft  9  is opposed to the first escape recessed portion  4   c  of the first hinge shaft  4 . 
     Furthermore, on the left side of this case cover  6 , a conducting wire guiding portion  6   j  is provided, and a conducting wire  30  led out from the first member  1  side is led via this conducting wire guiding portion  6   j  to the second member  2  side, as shown particularly in  FIG. 5 . 
     The first hinge shaft  4  is, as shown particularly in  FIG. 5 , restricted in the axial direction so as not to move in the axial direction by sandwiching the partition wall  6   a  of the case cover  6  between an E ring  11  attached to a second circumferential groove  4   d  formed on the outer periphery of the first hinge shaft  4  and the push nut  8 , and a guide plate  12  is attached in contact with the E ring  11  with the first hinge shaft  4  being inserted through an insertion hole  12   a  formed in the center portion thereof in the axial direction. 
     Between the E ring  11  and a flange portion  4   e  provided on a middle portion of the first hinge shaft  4 , as shown similarly in  FIG. 5 , an inner cam  13  is attached to be slidable in the axial direction with the first hinge shaft  4  being inserted through an inserting hole  13   a  formed in the center portion thereof in the axial direction, and between the inner cam  13  and the guide plate  12 , a coil spring  14  being wound on the first hinge shaft  4  and serving both as a compression spring and a torsion spring is resiliently disposed to slidably and rotatably bias the inner cam  13  in one direction by locking one end portion thereof, as shown particularly in  FIG. 11 , in a locking groove  12   b  formed in the insertion hole  12   a  of the guide plate  12 , and locking the other end portion thereof, as shown particularly in  FIG. 12 , in a locking groove  13   b  formed in an insertion hole  13   a  of the inner cam  13 , respectively. 
     The inner cam  13  has, as shown particularly in  FIG. 8  and  FIG. 12 , a pair of locking projections  13   c ,  13   c  formed on the outer periphery of one end portion side thereof and a first cam portion  15  is formed on an end surface of the other end portion thereof as shown in  FIG. 5  and  FIG. 8 , and is accommodated inside an outer cam  16  in a cylindrical shape arranged around the outer periphery thereof. The locking projections  13   c ,  13   c  of the inner cam  13  rotate in a circumferential direction and slide in an axial direction, and both movements take place inside first key grooves  16   c ,  16   c  and second key grooves  16   d ,  16   d  of an outer cam  16 ; when engaged with first key grooves  16   c ,  16   c , the locking projections  13   c ,  13   c  are retracted into the outer cam  16 , and when engaged with second key grooves  16   d ,  16   d , they protrude out of the outer cam  16  on the side of a first cam portion  15 ; a rotation thereof in a circumferential direction is restricted within the range equivalent to a sum of a width of either one of first key grooves  16   c ,  16   c  and that of either one of second key grooves  16   d ,  16   d . The most part of this outer cam  16  is inserted into an accommodating portion  6   e  formed in the case cover  6 , and as shown in  FIG. 13 , guide grooves  16   a ,  16   a  formed on the outer periphery thereof in the axial direction are engaged with projecting portions  6   f ,  6   f  as shown in  FIG. 9  formed in the accommodating portion  6   e  to be fixed into the case cover  6 . As shown in  FIG. 8 , a second cam portion  17  is provided on one end portion side of the outer cam  16 . Thus, the first cam portion  15  and the second cam portion  17  are overlapping with each other in a radial direction as shown in  FIG. 5  and  FIG. 21  to  FIG. 24 . The guide plate  12  provides a unidirectional rotation torque to the inner cam  13  via the coil spring  14  by engaging recessed portions  12   c ,  12   c  formed on the outer periphery thereof as shown particularly in  FIG. 11  being engaged with locking grooves  16   b ,  16   b  formed on the outer cam  16  as shown in  FIG. 13 . 
     On the left side of the first hinge shaft  4 , a cam follower  18  is attached, as shown in  FIG. 5 , so that a third cam portion  20  formed on an end surface thereof opposes the first and second cam portions  15 ,  17 , with the first hinge shaft  4  being inserted through an insertion hole  18   a  formed in the center portion thereof in the axial direction. This cam follower  18  is constructed to be restrained from rotating by the case  3  and to be slidable in the axial direction as shown in  FIG. 5  by engaging projecting portions  18   b ,  18   b  formed on the outer periphery thereof in the axial direction with recessed grooves  3   f ,  3   f  (refer to  FIG. 9 ) formed on the inner wall of the case  3  as shown in  FIG. 14 . Between this cam follower  18  and the inside of the side wall  3   d  of the case  3 , a compression spring  19  being wound on the first hinge shaft  4  is resiliently disposed as shown in  FIG. 5  to bias the cam follower  18  constantly to slide in a direction toward the inner cam  13  and the outer cam  16 . 
     Thus, the cam follower  18  is pushed toward the inner cam  13  and the outer cam  16  via the compression spring  19 , and the inner cam  13  and the outer cam  16  are pushed in a direction toward the cam follower  18  via the coil spring  14 , so that the first cam portion  15  of the inner cam  13  and the second cam portion  17  of the outer cam  16  are in pressure contact with the third cam portion  20  of the cam follower  18 , and further the inner cam  13  is biased to rotate in one direction by the coil spring  14 . 
     In a vertical rotation control means  25 , which controls a vertical rotation of a first member  1  with regard to a second member  2 , the following components are included: an inner cam  13  having a cam portion on an end portion thereof and arranged in said case cover  6  with the first hinge shaft  4  being inserted through a center portion thereof in the axial direction in a slidable and rotatable manner; a flange portion  4   e  provided in the first hinge shaft  4  to limit the axial direction sliding of the inner cam  13  up to a predetermined position; an outer cam  16  accommodating the inner cam  13  inside in a manner rotatable at a predetermined rotation angle and slidable in the axial direction, the outer cam  16  being accommodated in the case cover  6  in a state being restrained from rotating and having a cam portion  17  on an end portion thereof in the same direction as the cam portion  15  of the inner cam  13 ; a guide plate provided on the partition wall side of said case cover to be engaged with said outer cam, with said first hinge shaft being inserted in an axial core portion thereof in the axial direction; an outer cam  16  accommodating the inner cam  13  inside in a manner rotatable at a predetermined rotation angle and slidable in the axial direction, the outer cam  16  being accommodated in the case cover  6  in a state being restrained from rotating and having a cam portion  17  on an end portion thereof in the same direction as the cam portion  15  of the inner cam  13 ; a guide plate  12  provided on the partition wall  6   a  side of the case cover  6  to be engaged with the outer cam  16 , the said first hinge shaft  4  being inserted in an axial core portion thereof in the axial direction; a spring  14  resiliently provided between the inner cam  13  and the guide plate  12  in a state being wound on the first hinge shaft  4  to bias the inner cam  13  to rotate in one direction and to slide in one direction; a cam follower  18  in which the first hinge shaft  4  is inserted through an axial core portion thereof in the axial direction and a cam portion  20  is provided on a side corresponding to the inner cam  13  accommodated in the cover in a slidable manner in one direction; and a compression spring  19  which biases the cam follower  18  to slide in a direction of the inner cam  16  and the outer cam. 
     Next, on a substantially center portion of the second hinge shaft  9 , a flange portion  9   c  is provided as shown in  FIG. 6  to  FIG. 8  and  FIG. 17  to restrict movement of the second hinge shaft  9  in the axial direction. This second hinge shaft  9  is rotatably inserted through an insertion hole  21   a  formed in a base cam  21 , which is accommodated and fixed in an accommodating portion  6   h  formed inside the case cover  6 , to protrude outside the case cover  6 , and an attaching portion  9   d  having a substantially D shape on its cross-section formed on the tip portion thereof is inserted into and engaged with a deformed mounting hole  22   b  formed in on a side wall  22   d  of a mounting cylinder portion  22   a  at the center portion of a mounting member  22  having a substantially T shape, as shown in  FIG. 6 ,  FIG. 7  and  FIG. 18 . The second hinge shaft  9  has a circumferential groove  9   e  on a free end portion protruding more than the deformed mounting hole  22   b , and by attaching an E ring  23  on this circumferential groove  9   e , the mounting member  22  does not disengage from the second hinge shaft  9  and is locked to rotate with the mounting member  22 . Mounting pieces  22   g ,  22   g  penetrate the mounting cylinder portion  22   a  of the mounting member  22  so as to be installed therein; these mounting pieces  22   g ,  22   g  are thus fixedly attached to either one of tips of the second member  2 . In this mounting cylinder portion  22   a  of the mounting member  22 , an accommodating portion  22   c  is formed having an axial core common to that of the deformed mounting hole  22   b  as shown in  FIG. 6  and  FIG. 7 , and a rotary cam  24  is attached inside the accommodating portion  22   c  to be restrained therein from rotating and to be rotatable with the mounting member  22 , with the second hinge shaft  9  being inserted through an insertion hole  24   a  thereof. 
     Opposing faces of the base cam  21  and the rotary cam  24  are, as shown particularly in  FIG. 19  and  FIG. 20 , a first cam portion  28  for swiveling and a second cam portion  29  for swiveling are formed respectively. These cam portion  28  for swiveling and a second cam portion  29  for swiveling are in pressure contact with each other by a compression spring  27  which is, particularly as shown in  FIGS. 6 and 7 , wound on the second hinge shaft  9 , accommodated in the accommodating portion  22   c , and resiliently disposed between a side wall  22   d  of the mounting member  22  and the rotary cam  24 . 
     In a horizontal rotation control means  26 , which controls a horizontal rotation of a first member  1  with regard to a second member  2 , the following components are included: a first cam  28  for swiveling of a base cam  21 , in which the second hinge shaft  9  is inserted through a center portion thereof in the axial direction in a rotatable manner, provided on the case cover  6  side; a second cam  29  for swiveling of a rotary cam  24 , in which the second hinge shaft  9  is inserted through a center portion thereof in the axial direction in a slidable manner, attached on the second member  2 ; and a compression spring  27  wound on the second hinge shaft  9  to push the second cam  29  for swiveling toward the first cam  28  for swiveling. 
     Next, operation of the hinge B in accordance with the above structure will be described. As shown in  FIG. 26 , in a state that the receiver section  2  is closed with respect to the transmitter section  1  of the cellular phone A, a projecting portion  20   a  of the third cam portion  20  of the cam follower  18  is positioned at respective first inclined surfaces  15   b ,  17   b  of a first projecting portion  15   a  of the first cam portion  15  and a projecting portion  17   a  of the second cam portion  17  of the inner cam  13  and the outer cam  16  as shown in  FIG. 21 , so that the projecting portion  20   a  receives a force in a direction to close the receiver section  2  toward the transmitter section  1  due to the resilient force of the compression spring  19  as shown in  FIG. 5 , and thus it is in a locked state. 
     At this time, tips of the locking projections  13   c ,  13   c  of this inner cam  13  are positioned at first key grooves  16   c ,  16   c  (refer to  FIG. 13 ) at tip portions of the locking grooves  16   b ,  16   b  of the outer cam  16 , and in a state pulled inside the outer cam  16  against the resilient force of the coil spring  14 . Furthermore, this inner cam  13  intends to rotate to the left side in the drawing ( FIG. 21 ) by the rotation torque of the coil spring  14 , but this rotation is blocked by the projecting portion  20   a  of the third cam portion  20  of the cam follower  18 . 
     From this position, when the receiver section  2  is opened with respect to the transmitter section  1 , the projecting portion  17   a  of the second cam portion  17  of the outer cam  16  passes over the projecting portion  20   a  of the third cam portion  20  of the cam follower  18 ; therefore the outer cam  16 , on which a rotation torque is generated via the coil spring  14  and the inner cam  13 , and reaches the second inclined surface  17   c  as shown in  FIG. 22 , so that the receiver section  2  slides above the second inclined surface  17   c  and opens automatically up to 150° as shown in  FIG. 23 . On the other hand, the inner cam  13  rotates in the leftward direction by the restoring force (rotation torque) of the coil spring  14  and stops at a position shown in  FIG. 22 . 
     When opened up to 150°, the projecting portion  20   a  of the third cam portion  20  of the cam follower  18  stops by dropping into a recessed portion  17   d  of the second cam portion  17  of the outer cam  16  as shown in  FIG. 23 .  FIG. 27  shows a state that the first member  1  and the second member  2  are in this position. At this time, the first projecting portion  15   a  of the first cam  15  overlapping with the recessed portion  17   d  of the second cam  17  is pushed by the projecting portion  20   a  of the cam follower  18 , so that the inner cam  13  rotates in a rightward direction against the rotation torque of the coil spring  14 , and the tips of the locking projections  13   c ,  13   c  are at the position of the second key grooves  16   d ,  16   d  of the tip portions of the locking grooves  16   b ,  16   b  of the outer cam  16  (refer to  FIG. 13 ) and move in a direction to project more than the outer cam, thereby taking a state shown in  FIG. 23 . 
     Then, from this 150° open state, when the second member  2  is closed toward the first member  1  side, the inner cam  13 , forced by the projecting portion  20   a  of the cam follower  18  at a position of 90°, rotates to the right; further, since the locking projections  13   c ,  13   c  are located at second key grooves  16   d ,  16   d  with a rotation thereof being restricted, they climb a second inclined portion  15   f  of the inner cam  13 , pass over the second projecting portion  15   e , drop into a first recessed portion  15   c  side and are click-stopped therein. This state is shown in  FIG. 24  and  FIG. 28 . 
     In this state, as shown in  FIG. 7 , the first escape recessed portion  4   c  formed on the first hinge shaft  4  corresponds to the second escape recessed portion  9   b  formed on the second hinge shaft  9 , allowing rotation of the second hinge shaft  9 , so that the second member  2  can rotate leftward and rightward in a horizontal direction with respect to the first member  1  as shown in  FIG. 29 . This rotation angle is restricted as shown in  FIG. 8  and  FIG. 18  by a stopper portion  22   e  of the mounting member  22  coming into contact with a stopper wall  6   i  formed in the second accommodating portion  6   h  formed inside the case cover  6  as shown in  FIG. 10 , and is 180° in both the rightward and leftward rotational directions in this embodiment 1. 
     The second member  2  is in a locked state at the 0° position since it is biased to rotate in the closing direction by the resilient force of the compression spring  27  and by respective cam portions  28 ,  29  of the first cam portion  28  for swiveling and the second cam portion  29  for swiveling with respective projecting portions  28   a ,  29   a  and recessed portions  28   b ,  29   b  being in an engaged state. The second member  2  is devised to stop freely at an intermediate rotation angle by operation of a friction torque due to the respective projecting portions  28   a ,  29   a  being in a pressure contact state, and to keep a 180° position by being biased again at the 180° position to rotate so that the respective projecting portions  28   a ,  29   a  engage with the recessed portions  28   b ,  29   b.    
     When the second member  2 , once closed up to 90° from a fully opened state (at 150°) with respect to the first member  1 , is pushed further in the closing direction, the projecting portion  20   a  of the third cam portion  20  of the cam follower  18  ascends the second inclined surface  17   c  of the second cam portion  17  of the outer cam  15  to be closed, thereby taking a state shown in  FIG. 25 . When the second member  2  is further closed from this state, it takes a state shown in  FIG. 21  to be locked at the close position of 0°. 
     Just before the second member  2  is opened 150° with respect to the first member  1 , the projecting portion  20   a  of the third cam portion  20  of the cam follower  18  drops into the recessed portion  17   d  of the second cam portion  17  of the outer cam  16  to be locked at the open position.