Abstract:
A display tilting apparatus includes a moving bracket that supports a display, a ratchet mechanism that controls pivoting of the moving bracket to a first direction, an anti-tilting mechanism that inhibits pivoting of the moving bracket to a second direction that is opposite of the first direction, and a fixed bracket that is pivotably connected to the moving bracket via a pivot axis. The anti-tilting mechanism includes a first anti-tilting member, and a second anti-tilting member that is mounted on the fixed bracket. The first anti-tilting member and the second anti-tilting member are mounted so as to make a physical contact to each other.

Description:
BACKGROUND OF THE INVENTION 
     1) Field of the Invention 
     The present invention relates to a technology for adjusting an angle of a liquid-crystal display (LCD) screen to improve operationality and safety by using a tilt-locking function of a ratchet mechanism and a anti-tilting function of an anti-tilting mechanism. 
     2) Description of the Related Art 
     Point-of-sales (POS) terminals are widely used in department stores and the restaurants as an information-display apparatus having an LCD screen.  FIG. 8A  and  FIG. 8B  are a perspective view and a side view of a conventional POS terminal  100 , respectively. The POS terminal  100  includes an LCD screen  200 , on which the operator performs the key-touch operation (for accounting operation or the like), a main body  100   a , a printer  300 , which prints a printing paper such as a receipt, and a controller  400 . A receipt exit  500  is used to issue the receipts that the printer  300  prints. 
     A hinge  550  connects the LCD screen  200  and the main body  100   a , and the ratchet mechanism (not shown), which includes a function for adjusting an angle of the LCD screen  200 , is arranged in the hinge  550 . In the operation of the LCD screen  200 , the operator adjusts the angle of the LCD screen  200  to be a desirable position using the ratchet mechanism. 
     Japanese Patent Application Laid-Open No. 2000-300370 discloses an example of the display tilting apparatus that is used to connect a backrest and a seat of a legless chair, a sofa bed, or the like. This display tilting apparatus adjusts the angle of the backrest or the like to be a desirable position stepwise using the ratchet mechanism. 
     Another example of the display tilting apparatus that adjusts the angle of the LCD screen is a torque-hinge mechanism that uses a friction torque. The notebook computer has the torque-hinge mechanism, and the torque-hinge mechanism is arranged in a hinge that connects the LCD screen and a main body (keyboard). The LCD screen is tilted and fixed at any desirable position using the friction torque of the torque-hinge mechanism. 
     However, the conventional technologies have the following problems in adjusting the angle of the LCD screen. When the hinge has the ratchet mechanism, the LCD screen  200  can be fixed at any desirable position on the printer&#39;s side by engaging a ratchet gear with a locking pawl (to lock). On the other hand, the tilt-locking function of the ratchet mechanism does not work when the LCD screen  200  tilts to the operator&#39;s side, and the LCD screen  200  unexpectedly falls toward the operator. Therefore, there is a problem in safety when the ratchet mechanism is arranged in the hinge of the POS terminal. 
     When the hinge of the POS terminal has the torque-hinge mechanism, the LCD screen  200  can be tilted and supported at any desirable position using the friction torque (the friction drag) of the torque-hinge mechanism. 
     When the operator adjusts the angle of the LCD screen, preferably, the angle of the LCD screen can be adjusted with the comparatively weak force by configuring the strength of the friction torque similarly with the ratchet mechanism. On the other hand, when the operator performs the key-touch operation on the LCD screen and put some pressure on the LCD screen, it is required to have strength for retaining the angle of the LCD screen. Therefore, satisfying the contradict friction-torques is extremely difficult. 
     SUMMARY OF THE INVENTION 
     It is an object of the present invention to solve at least the problems in the conventional technology. 
     The display tilting apparatus according to one aspect of the present invention includes a moving bracket that supports a display; a ratchet mechanism that controls pivoting of the moving bracket to a first direction; an anti-tilting mechanism that inhibits pivoting of the moving bracket to a second direction that is opposite of the first direction; and a fixed bracket that is pivotably connected to the moving bracket via a pivot axis. The anti-tilting mechanism includes a first anti-tilting member that inhibits pivoting of the moving bracket; and a second anti-tilting member that is mounted on the fixed bracket. The first anti-tilting member and the second anti-tilting member are mounted so as to make a physical contact to each other. 
     The display tilting apparatus according to anther aspect of the present invention includes a moving bracket that pivotably supports a display; a ratchet mechanism that controls pivoting of the moving bracket to a first direction; an anti-tilting mechanism that inhibits pivoting of the moving bracket to a second direction that is opposite of the first direction; and a fixed bracket that is pivotably connected to the moving bracket via a pivot axis. The anti-tilting mechanism includes an anti-tilting member that inhibits pivoting of the moving bracket. The anti-tilting member includes a first surface that has a first salient part, and the fixed bracket includes a second surface that has a second salient part. The first surface and the second surface make a contact to each other. 
     The other objects, features, and advantages of the present invention are specifically set forth in or will become apparent from the following detailed description of the invention when read in conjunction with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a side view of a display tilting apparatus according to a first embodiment of the present invention; 
         FIG. 2  is an exploded view of the display tilting apparatus; 
         FIG. 3  is a cross-section of main parts of the display tilting apparatus; 
         FIG. 4A  is a plan view of a fixed-side anti-tilting plate; 
         FIG. 4B  is a plan view of a moving-side anti-tilting plate; 
         FIG. 5A  is a side view of an LCD screen for illustrating adjustment of a tilting position by ratchet mechanism (up position); 
         FIG. 5B  is a side view of the LCD screen for illustrating adjustment of the tilting position by ratchet mechanism (down position); 
         FIG. 6A  is a side view of the LCD screen for illustrating adjustment of the tilting position by a moving-side anti-tilting mechanism (up position, 0 degree); 
         FIG. 6B  is a side view of the LCD screen for illustrating adjustment of the tilting position by the moving-side anti-tilting mechanism (down position, 45 degrees); 
         FIG. 6C  is a side view of the LCD screen for illustrating adjustment of the tilting position by the moving-side anti-tilting mechanism (down position, 90 degrees); 
         FIG. 7A  is an enlarged cross-section of the fixed-side anti-tilting plate and the moving-side anti-tilting plate in a state that salient parts of both sides are making a contact to each other; 
         FIG. 7B  is an enlarged cross-section of the fixed-side anti-tilting plate and the moving-side anti-tilting plate in a state that the salient parts of the both sides are released from each other; 
         FIG. 8A  is a perspective of a conventional POS terminal; and 
         FIG. 8B  is a side view of the conventional POS terminal. 
     
    
    
     DETAILED DESCRIPTION 
     Exemplary embodiments of a display tilting apparatus according to the present invention are explained in detail with reference to the accompanying diagrams. In explanations of a first embodiment and a second embodiment, it is assumed that the information-display apparatus is a POS terminal and the display tilting apparatus is arranged in the hinge of the POS terminal. The configuration and the function of the present invention are not limited to those of the first embodiment and the second embodiment. 
       FIG. 1  is a side view of a display tilting apparatus according to a first embodiment of the present invention.  FIG. 2  is an exploded view of the display tilting apparatus.  FIG. 3  is a cross-section of main parts of the display tilting apparatus. 
     A POS terminal  110  includes the LCD screen  200 , on which the operator performs the key-touch operation (for accounting operation), the main body  100   a , the printer  300 , which prints a printing paper such as a receipt, and a controller  400 . The both sides of the LCD screen  200  are fitted with a pair of moving brackets  700  using screws, and a fixed bracket  800 , which is connected to an end of the moving bracket  700 , is fitted with a side  410  of the main body  100   a  using screws. A display tilting apparatus  600  according to the present invention is arranged in a connection (a hinge) between the moving bracket  700  and the fixed bracket  800 . 
     As shown in  FIG. 1  and  FIG. 2 , the display tilting apparatus  600  includes a ratchet mechanism  610 , which tilts the LCD screen  200  to the first pivot-direction (toward printer side) and adjusts the angle of the LCD screen  200  to be any desirable angle, and an anti-tilting mechanism  620 , which tilts the LCD screen  200  to the second pivot-direction (toward operator side) and inhibits the angle of the LCD screen  200  to be any desirable angle. The ratchet mechanism  610  is arranged between the moving bracket  700  and the fixed bracket  800 , and the anti-tilting mechanism  620  is arranged so that the fixed bracket  800  is arranged between the ratchet mechanism  610  and the anti-tilting mechanism  620 . 
     The feature of the display tilting apparatus  600  according to the first embodiment is that the ratchet mechanism  610  adjusts the angle of the LCD screen  200  to the first pivot-direction by adjusting the position where a ratchet gear  630  is engaged with a locking pawl  640  (hereinafter, “an engaged position”), and the anti-tilting function of the anti-tilting mechanism  620  adjusts the angle of the LCD screen  200  to the second pivot-direction (regarding the engaged position, three engaged positions are shown in  FIG. 1 ). Actually, the anti-tilting mechanism  620  is not prepared for adjusting the angle of the LCD screen  200 , but prepared for inhibiting the LCD screen  200  from falling toward the operator&#39;s side unexpectedly. 
     As shown in  FIG. 2  and  FIG. 3 , the ratchet mechanism  610  includes the ratchet gear  630 , a cam  638  for operating a locking pawl, the locking pawl  640 , and a coil spring  650 . A plurality of ratchet teeth  631  are formed in the ratchet gear  630  (three ratchet teeth  631  are shown in  FIG. 2 ). A through-hole  632  is arranged in the center of the ratchet gear  630 . A pivot shaft  633  includes a step  634 , has the D-shape, and is fitted into the through-hole  632 . Although the ratchet gear  630  and the pivot shaft  633  are separated in the present embodiment, the ratchet gear  630  and the pivot shaft  633  may be configures to integrate each other. 
     The coil spring  650  is fitted around a rivet  810 , which is fixed in the fixed bracket  800 , and powered so that the ratchet tooth  631  of the ratchet gear  630  is engaged with the locking pawl  640 . By engaging the ratchet gear  630  with the locking pawl  640 , the angle of the LCD screen  200  is retained at a certain angle. Consequently, the angle of the LCD screen  200  can be adjusted by adjusting the engaged position of the ratchet gear  630  and the locking pawl  640  (three engaged positions are shown in  FIG. 2 ). 
     The pivot shaft  633  penetrates a circular hole  815 , which is formed in the fixed bracket  800 , a circular hole  721  of a fixed-side anti-tilting plate  710 , which the anti-tilting mechanism  620  includes, and a hole  780  of a moving-side anti-tilting plate  750 . The end of the pivot shaft  633  is fixed by caulking via two spring washers  900  and a washer  910 . Therefore, the moving-side anti-tilting plate  750  and the fixed-side anti-tilting plate  710  are mounted to clamp each other using the spring washers  900 . Moreover, the step  634  formed on the pivot shaft  633  is fitted into the circular hole  721  of the fixed-side anti-tilting plate  710 . Consequently, the LCD screen  200  can pivot stably. 
     The anti-tilting mechanism  620  includes the fixed-side anti-tilting plate  710  and the moving-side anti-tilting plate  750 , which are formed circular, and the fixed-side anti-tilting plate  710  and the moving-side anti-tilting plate  750  are mounted so that a side of the fixed-side anti-tilting plate  710  and a side of the moving-side anti-tilting plate  750  clamp each other. 
       FIG. 4A  is a plan view of a fixed-side anti-tilting plate  710 ; and  FIG. 4B  is a plan view of a moving-side anti-tilting plate  750 . In the center of the fixed-side anti-tilting plate  710 , the circular hole  721 , into which the step  634  of the pivot shaft  633  can be fitted, is formed and a plurality of small circular-holes  722 , which can be engaged with engaging pins  816  mounted on the end of the fixed bracket  800 , are formed (four small circular-holes  722  are shown in  FIG. 4A ). On a side, where the engaging pins  816  do not slide, of the fixed-side anti-tilting plate  710 , a plurality of salient parts  720  are formed (four salient parts  720  are shown in  FIG. 4A ). The salient parts  720  are formed to make an angle of 90 degrees to each other. The small circular-hole  722  is formed in a concave part  730 . Although the salient parts  720  are formed to make an angle of 90 degrees to each other in the present embodiment, the number of the salient parts  720  and the positions where the salient part  720  are formed are not to be thus limited but may be specified appropriately. 
     In the center of the moving-side anti-tilting plate  750 , the hole  780 , which the end of the pivot shaft  633  can be engaged into and has a D-shape, is formed. On the side of the moving-side anti-tilting plate  750 , a plurality of salient parts  790  are formed (four salient parts  790  are shown in  FIG. 4A ). The fixed-side anti-tilting plate  710  and the moving-side anti-tilting plate  750  are mounted so that the salient parts  720  and the salient parts  790  clamp each other. 
       FIG. 5A  and  FIG. 5B  are side views of an LCD screen for illustrating adjustment of a tilting position by ratchet mechanism with an up position and a down position, respectively. The ratchet mechanism  610  adjusts the angle of the LCD screen  200  to the first pivot-direction by adjusting the engaged position (three engaged positions) of the ratchet gear  630  and the locking pawl  640 . The angle of the LCD screen  200  is in the initial state, and adjusted by engaging a ratchet tooth  631 A, which is the middle ratchet tooth of the ratchet teeth  631 , with the locking pawl  640 . The LCD screen  200  is more tilted to the printer&#39;s side, and the angel of the LCD screen  200  is adjusted by engaging a ratchet tooth  631 B, which is the upper ratchet tooth of the ratchet teeth  631 , with the locking pawl  640 . 
       FIG. 6A ,  FIG. 6B , and  FIG. 6C  are side views of the LCD screen for illustrating adjustment of the tilting position by a moving-side anti-tilting mechanism with an up position (0 degree), a down position, (45 degrees), and a down position (90 degrees), respectivley. The LCD screen  200  shown in  FIG. 6A  is not tilted, the LCD screen  200  shown in  FIG. 6B  is tilted at 45 degrees, and the LCD screen  200  shown in  FIG. 6C  is tilted at 90 degrees. 
     When the operator tilts the LCD screen  200  to the front side (toward operator side), that is, the state of the LCD screen  200  changes from the state shown in  FIG. 6A  to the state shown in  FIG. 6B  or  FIG. 6C , the moving bracket  700  fitted on the LCD screen  200  pivots with the LCD screen  200 , and the pivot shaft  633 , which is connected to the moving bracket  700 , pivots with the LCD screen and drives the moving-side anti-tilting plate  750  to pivot. When the moving bracket  700  pivots, the salient part  790  formed on the moving-side anti-tilting plate  750  and the salient part  720  of the fixed-side anti-tilting plate  710 , which are clamped on each other, interfere with each other, so that the friction torque occurs. 
       FIG. 7A  and  FIG. 7B  are enlarged cross-sections of the fixed-side anti-tilting plate  710  and the moving-side anti-tilting plate  750  in a state that salient parts of both sides are making a contact to each other and in a state that the salient parts of the both sides are released from each other, respectively. In the state shown in  FIG. 7A , the salient part  720  and the salient part  790  are clamped on each other and interfere with each other, so that it is prevented that the LCD screen  200  pivots unexpectedly. On the other hand, in the state shown in  FIG. 7B , the operator pivots the moving bracket  700 , so that the salient part  720  and the salient part  790  are not clamped on each other any more and the concave part  730  of the fixed-side anti-tilting plate  710  is engaged with the salient part  790  of the moving-side anti-tilting plate  750 . In this case, the fixed-side anti-tilting plate  710  and the moving-side anti-tilting plate  750  do not interfere with each other, so that the operator can pivot the LCD screen  200  manually and easily. 
     In this manner, the display tilting apparatus  600  according to the first embodiment, the display tilting apparatus  600  includes the ratchet mechanism  610 , which pivots the LCD screen  200  to the first pivot-direction, and the anti-tilting mechanism  620 , which inhibits the LCD-screen  200  from pivoting to the second pivot-direction. Consequently, the LCD screen  200  can be pivoted to the first pivot-direction and the angel of the LCD screen  200  can be adjusted comparatively easily using the ratchet mechanism  610 . Moreover, the LCD screen  200 , whose angle is adjusted by the ratchet mechanism  610 , can be supported with retention strength by engaging the ratchet gear  630  with the locking pawl  640  even when the operator performs the key-touch operation on the LCD screen  200 . 
     On the other hand, in tilting the LCD screen  200  to the operator&#39;s side, the anti-tilting mechanism  620  inhibits the LCD screen  200  from pivoting unexpectedly. Consequently, the anti-tilting mechanism  620  prevents the LCD screen  200  from tilting to the operator&#39;s side unexpectedly. 
     Although the display tilting apparatus  600  includes the fixed-side anti-tilting plate  710  and the moving-side anti-tilting plate  750  in the first embodiment, in a second embodiment, the fixed-side anti-tilting plate  710  may be omitted by forming the salient part  720  on the side (the end) of the fixed bracket  800  directly. In the second embodiment, the effect, which is same as the first embodiment, of the anti-tilting function is realized by clamping the salient part  790 , which is formed on the surface of the moving-side anti-tilting plate  750 , on the salient part  720 , which is formed on the surface of the fixed bracket  800 . 
     In this manner, in the second embodiment, the same effect as the first embodiment is realized, and the cost reduction is realized by reducing the number of the components, namely by omitting the fixed-side anti-tilting plate  710 . 
     Although the display tilting apparatus is applied to the LCD screen of the POS terminal in the first embodiment and the second embodiment, the present invention is not to be thus limited but may be applied to the panels, for customers, of the commutation-ticket vending machine and the automatic teller machine (ATM) of the bank and the like. 
     As stated above, the display tilting apparatus according to the present invention is useful in adjusting the angle of the LCD screen, and especially, suitable for adjusting the angle of the LCD screen of the information-display apparatus, such as the POS terminal. 
     Consequently, the effect of the present invention is that the angle of the LCD screen to the operator&#39;s side can be adjusted to any desirable angle stepwise, it is prevented that the LCD screen tilts to the operator&#39;s side unexpectedly and undisturbedly, the operatability improves, and the LCD screen pivots stably even when the anti-tilting function works. 
     Although the invention has been described with respect to a specific embodiment for a complete and clear disclosure, the appended claims are not to be thus limited but are to be construed as embodying all modifications and alternative constructions that may occur to one skilled in the art which fairly fall within the basic teaching herein set forth.