Abstract:
A hinge assembly ( 300 ) for use in a flat display monitor includes a support seat ( 10 ), a base seat ( 20 ) and a pivot mechanism. The support seat has a cutout ( 164 ) defined by two opposed side surfaces. The base seat includes a resisting member disposed thereon. The pivot mechanism rotatably connects the support seat to the base seat. A resisting member ( 94 ) on the base seat is movable in the cutout of the support seat upon rotating of the support seat relative to the base seat. The two side surfaces are configured to engage with the resisting member when the support seat rotates relative to the base seat in a manner so as to prevent the resisting member from moving further to limit a rotation angle between the support seat and the base seat.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention generally relates to hinge assemblies and, particularly, to a hinge assembly for a flat display monitor. 
       DISCUSSION OF THE RELATED ART 
       [0002]    With the widespread use and the variety of computers available, display devices configured for such a variety of computers also come in a wide range of sizes, shapes, and weight. In general, a typical cathode-ray tube (CRT) monitor includes a display panel for displaying an image, a vacuum tube coupled to the rear of the display panel, and an electron gun coupled to the rear of the vacuum tube. This configuration is a huge factor in limiting the total volume and final weight of the CRT monitor. In addition, the CRT monitor carries a huge problem in that a user is easily fatigued when looking at the CRT monitor over several hours due to its low image quality. It is this problem alone that many people switched to using a flat screen display monitor, e.g., liquid crystal display (LCD) monitor, from the conventional CRT monitors. Such flat display monitors generally offer the advantages of a greatly reduced size and weight properties including the ability to produce a high image quality. Furthermore, flat screen display monitors may help to overcome space limitations through folding over (such as with a laptop computer) or rotating (such as with a desktop monitor) so as to facilitate adjustment of the position thereof relative to the user. 
         [0003]    The rotating or folding-over functions of the flat display monitor are realized with a hinge assembly. Such a hinge assembly includes an L-shaped fixed seat, a pivotal axle, and a number of oiled washers. The fixed seat has a retaining hole defined therein. The pivotal axle is pivotally connected with the fixed seat. The pivotal axle has a retaining shoulder formed at a middle portion thereof, a connecting end portion integrally formed at a first end of the retaining shoulder, and a fixing end portion integrally formed at a second end of the retaining shoulder. The connecting end portion of the pivotal axle extends through a retaining hole of the fixed seat along with the oiled washers, and then fastened by a fastening piece. The hinge assembly may realize a maximum inclination angle of the flat display monitor so that the LCD shall not over fold, over shifting a center of gravity, causing the LCD to fall over. However, in use, it needs to use great efforts to rotate the hinge assembly, since a greater force is exerted thereon. As a result, it is inconvenient for a user to operate the hinge assembly. 
         [0004]    Therefore, a new hinge assembly is desired in order to overcome the above-described shortcomings. 
       SUMMARY 
       [0005]    In one embodiment thereof, a hinge assembly for use in a flat display monitor includes a support seat, a base seat and a pivot mechanism. The support seat has a cutout defined by two opposed side surfaces. The base seat includes a resisting member disposed thereon. The pivot mechanism rotatably connects the support seat to the base seat. A resisting member on the base seat is movable in the cutout of the support seat upon rotating of the support seat relative to the base seat. The two side surfaces are configured to engage with the resisting member when the support seat rotates relative to the base seat in a manner so as to prevent the resisting member from moving further to limit a rotation angle between the support seat and the base seat. 
         [0006]    Other advantages and novel features will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0007]    Many aspects of the hinge assembly can be better understood with reference to the following drawings. The components in the drawings are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of the hinge assembly. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views. 
           [0008]      FIG. 1  is an isometric view of an embodiment of a hinge assembly, as used in a flat display monitor; 
           [0009]      FIG. 2  is an exploded, isometric view of the hinge assembly in  FIG. 1 ; 
           [0010]      FIG. 3  is an assembled, isometric view of t the hinge assembly in  FIG. 2  viewed from a first direction; 
           [0011]      FIG. 4  is similar to  FIG. 3 , but viewed from a second direction; and 
           [0012]      FIG. 5  is a cut-away view taken along line V-V in  FIG. 3 . 
       
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
       [0013]    Referring to drawings in detail,  FIG. 1  shows a flat display monitor employing a hinge assembly  300  in accordance with one embodiment of the present application. The flat display monitor is taken here as an exemplary application, for the purposes of describing details of the hinge assembly  300 . It is to be understood, however, that the hinge assembly  300  could be advantageously used in other environments (e.g. cabinet doors). As such, although providing particularly advantages when used in flat display monitors, the hinge assembly  300  should not be considered limited in scope solely to an intended use environment of flats display monitors. The flat display monitor includes a display unit  100  and a support body  200 . The hinge assembly  300  connects the display unit  100  to the support body  200  such that the display unit  100  can be pivoted relative to the support body  200 . 
         [0014]    Referring to  FIG. 2 , the hinge assembly  300  includes a support seat  10 , a base seat  20 , and two pivot mechanisms (not labeled) each including a pivotal shaft  30 , two tab washers  41  and  42 , two washers  51  and  52 , a pair of Belleville/cupped spring washers  61  and  62 , a resilient element  70 , a limiting washer  80 , and a screw nut  90 . 
         [0015]    The support seat  10  includes a mounting portion  12 , a connecting portion  14  and two extending portions  16 . The mounting portion  12  and the connecting portion  14  are substantially boards with the connecting portion  14  being thicker than the mounting portion  12 . The mounting portion  12  has a surface  120  and defines a plurality of mounting holes  122 . In this embodiment, there are four mounting holes  122 . The support seat  10  is mounted to the support body  200  by means of the mounting holes  122 . One end of the connecting portion  14  is connected to the mounting portion  12  and an opposite end forms two protrusions  142 . Each of the protrusions  142  is a triangular prism defining a fixing slot  144  on a side of the surface  120  of the support seat  10 . The extending portions  16  extend at exterior sides of the protrusions  142  and are slanted toward the surface  120 . The extending portions  16  are cylinders each defining a central pivoting hole  160  and a cutout  164  at a periphery thereof. One end of each extending portion  16  defines an end groove  162  and an opposite end of each extending portion  16  defines an end groove  163 . Each extending portion  16  defines two opposite receiving slots (not labeled) adjacent to the end grooves  162  and  163 . 
         [0016]    The base seat  20  includes a fixing board  22  and two side boards  24  disposed at two ends of the fixing board  22 . The fixing board  22  defines a plurality of threaded assembling holes  222 . In this embodiment, there are four assembling holes  222 . The base seat  20  is mounted to the display unit  100  by means of the assembling holes  222 . The side boards  24  are formed on two opposite edges of the fixing board  22  perpendicularly extending outward. Each of the side boards  24  defines an engaging hole  242  and a threaded fixing hole  244 . The engaging holes  242  are deformed, i.e., are non-round holes. Two bolts  94  are provided to screw into the fixing holes  244 . Most of the bolts  94  extend between the two side boards  24 . 
         [0017]    The pivotal shaft  30  is substantially cylindrical in shape. The pivotal shaft  30  includes a bolt cap  302  and a bolt shaft  306 . The bolt cap  302  is substantially a disk-like shape. The bolt shaft  306  defines a thread  308  on a distal end portion thereof opposite to the bolt cap  302 . The bolt shaft  306  is flattened along a section of the curved surface area thus forming a flat surface  304 . Thereby, the thread  308  is non-continuous and the section of the bolt shaft  306  corresponds to the shape and size of the engaging hole  242  of the base seat  20 . The bolt shaft  306  passes through the engaging hole  242  of the base seat  20  and the pivoting hole  160  of the support seat  10 . 
         [0018]    The tab washers  41  and  42  are approximately ring-shaped. Two opposite tabs  412  are formed at a periphery of the tab washer  41 , and two opposite tabs  422  are formed at a periphery of the tab washer  42 . The tabs  412 ,  422  of the tab washers  41 ,  42  are configured to engage in the receiving slots of the extending portion  16  of the support seat  10 . 
         [0019]    The washers  51  and  52  are approximately ring-shaped. The washers  51  and  52  define a first latching hole  512  and  522  respectively. The latching holes  512  and  522  each has a shape and size corresponding to the engaging hole  242  of the base seat  20 . 
         [0020]    The Belleville washers  61  and  62  are plate-shaped. The Belleville washers are configured to provide an axial force. An amount of friction that helps the display unit  100  retain at any desired positions relative to the support body  200  is generated between the elements of the pivot mechanisms. 
         [0021]    The resilient element  70  is a helical torsion spring having a first latching end  702  and a second latching end  704 . The first latching end  702  extends along a radial direction of the resilient element  70  and the second latching end  704  extends along an axial direction. When the hinge assembly  300  is assembled, the resilient element  70  exerts a predetermined torsion force. A diameter of the resilient element  80  is larger than that of the tab washers  41  and  42 , the washers  51  and  52 , and the Belleville washers  61  and  62 . 
         [0022]    The limiting washer  80  is approximately ring-shaped. The limiting washer  80  defines a second latching hole  802 . The second latching hole  802  has a shape and size corresponding to the engaging hole  242  of the base seat  20 . The limiting washer  80  forms a limiting block  804  at its periphery. The limiting block  804  approximately extends along an involute of the limiting washer  80 . 
         [0023]    The screw nut  90  defines a thread  902  therein for engaging with the thread  308  of the bolt shaft  306  of the pivotal shaft  30 . 
         [0024]    During assembly, referring now to  FIGS. 3-5 , the tab washers  41  and  42  are disposed in the end grooves  162  and  163  of the support seat  10 . The tabs  412  and  422  of the tab washers  41  and  42  engage in corresponding receiving slots of the support seat  10  so as to make the tab washers  41  and  42  non-rotatable relative to the support seat  10 . One resilient element  70  is placed around the bolt shaft  306  of each pivotal shaft  30  corresponding. The resilient element  70  has a predetermined torque force. The bolt shaft  306  of the pivotal shaft  30  passes through the engaging hole  242  of one side board  24  of the base seat  20 , one tab washer  41 , the pivoting hole  160  of one extending portion  16  of the support seat  10 , one tab washer  42 , one washer  51 , two Belleville washers  61  and  62 , one washer  52 , and one limiting washer  80 , in that order. The Belleville washers  61  and  62  are disposed opposite to each other. The first latching end  702  of the resilient element  70  is inserted into the fixing slot  144  of the support seat  10 , the second latching end  704  of the resilient element  70  resists the limiting block  804  of the limiting washer  80 . The screw nut  90  is fixed via the thread  308  of the pivotal shaft  30 . The screw nut  90  is adjoined to the limiting washer  80 . Thereby, a pivot mechanism is assembled. Another pivot mechanism is assembled in a similar manner. The bolts  94  are threaded in the fixing holes  244  of the base seat  20  and disposed in the cutout  164  of the support seat  10  so as to limit the rotation angle of the base seat  20  relative to the support seat  10 . Therefore, a rotation angle of the display unit  100  relative to the support body  200  is limited in a desired scope. 
         [0025]    After assembling, the tab washers  41  and  42 , the washers  51  and  52 , the Belleville washers  61  and  62 , and the limiting washer  80  collaboratively maintain the desired spacing between the various portions of the pivot mechanism of the hinge assembly  300 . Furthermore, the tab washers  41  and  42 , the washers  51  and  52 , the Belleville washers  61  and  62 , and the limiting washer  80  together help provide an amount of friction that allows movement of the display unit  100  relative to the support body  200  upon application of a moderate force but that, otherwise, helps retain the desired position between the support body  200  and the display unit  100 . Part of the required friction can be expected to be gained through the operation of the other elements of the hinge assembly  300 , as well. 
         [0026]    In use, a pushing force is exerted on the display unit  100 , and, in turn, the display unit  100  causes the base seat  20  to likewise move. The washers  51  and  52  and the limiting washers  80  also rotate together with the base seat  20 . Accordingly, the second latching ends  704  of the resilient elements  70  which resist the limiting blocks  804  of the limiting washers  80  rotate, whereby increase or decrease the torsion force of the resilient elements  70 . Suppose that the display unit  100  is in a middle position, the torsion force of the resilient elements  70  increases when the display unit  100  rotates towards a first direction and the torsion force decreases when the display unit  100  rotates towards an opposite second direction. The support seat  10  is fixed relative to the support body  200 . When the display unit  100  rotates through a determined angle toward the first direction or a determined angle toward the second direction, the bolts  94  fixed relative to the base seat  20  resists a wall defined in the cutout  164  of the support seat  10 . Thereby, the display unit  100  together with the base seat  20  cannot rotate further. The tab washers  41  disposed between the support seat  10  and the base seat  20  may decrease the abrasion between the support seat  10  and the base seat  20  so as to prolong the use life. 
         [0027]    In alternative embodiments, the pivotal shaft  30  is fastened, e.g., by means of other holding members such as a rivet or by a ring. In this manner, a C-shaped ring and a receiving groove for example, replace the screw nut  70  and the thread  308  of the bolt shaft  306 . Only a single pivot mechanism may be provided. Accordingly, the extending portion  16  of the support seat  10 , the side board  24  of the base seat  20  and the bolt  94  may also exist singularly. The cutout  164  may be omitted, and instead, a first resisting portion and a second resisting portion are formed on the support seat  10 . The support seat  10  may be a single piece without extending portions  16 . The bolt  94  may be replaced by other resisting members such as a pin or a protrusion formed on the base seat  20 . Other elastic members such as springs or other elastic washers may replace the Belleville washers  61 ,  62 . The support seat  10  may be mounted to the display unit  100 , and accordingly the base seat  20  may be mounted to the support body  200 . 
         [0028]    As described above, the preferred embodiments provides a hinge assembly  300  for devices such as a flat display screen, which is convenient for a user to operate and durable. It is, however, to be understood that the hinge assembly  300  could potentially be useful in other applications (e.g., a free-standing, adjustable mirror) in which it may be desirable to allow selective pivoting over a limited angular range. 
         [0029]    It is believed that the present embodiments and their advantages will be understood from the foregoing description, and it will be apparent that various changes may be made thereto without departing from the spirit and scope of the invention or sacrificing all of its material advantages, the examples hereinbefore described merely being preferred or exemplary embodiments of the invention.