Abstract:
A rear projection television includes a casing with a space therein and a plurality of modular units. A plurality of maintenance holes are formed through the casing to communicate with the space. The modular units are positioned in the space to correspond to the maintenance holes. When one component inside the casing needs repairing, only a lid covering the corresponding maintenance hole is dismounted for the user to quickly take the component out, without moving the casing. Thereby, the repair process is simplified with saved repair labor and space.

Description:
BACKGROUND OF INVENTION  
         [0001]    1. Field of the Invention  
           [0002]    The invention relates to a projection TV, and more particularly to a projection TV that is convenient to repair.  
           [0003]    2. Description of the Prior Art  
           [0004]    Referring to FIG. 1, a conventional rear projection television includes a base  11 , a front frame  12  and a rear cover  13 . The base  11  has an opening  111  at its top portion. Referring to FIG. 2, main components of the rear projection television such as a light engine, a circuit board, a power supply (not shown) are mounted in a basket  11  via an opening  111 . The front frame  12  and a screen (not shown) are assembled onto the basket  11 . A reflector is mounted at an inner side of the rear cover  13 . The front frame  12  is mounted on a front of the rear cover  13  to complete the assembly of the rear projection television.  
           [0005]    A conventional rear projection television usually uses a high-power and high-light flux discharge lamp such as metal halide lamp (MHL) and ultra high pressure mercury arc lamp (UHP) to achieve image output with high brightness and high display quality. However, such a lamp has high power consumption and a short service life. Therefore, the lamp needs to be replaced frequently. Furthermore, a circuit board and a power supply respectively consist of electric devices that may be defective and damaged after use for a period. When the lamp or the electric devices need repairing, the front frame  12  and the rear cover  13  must be dismounted before the devices are taken out from the basket  11  via the opening  111 . After the defective or damaged lamp or electric devices have been repaired, they are put in place in the casing and then the front frame  12  and the rear cover  13  are assembled back to the basket  11 . For example, when the lamp is to be replaced, the light engine as a whole must be taken out to replace the damaged lamp with a new one. Such a repair method has to change the position of the light engine, the reflector and the screen, adversely affecting the light path. Moreover, frequently moving the light engine tends to damage the electric devices and optical elements inside the casing. As the rear projection television becomes increasingly larger, it requires more repair space and labor expertise.  
         SUMMARY OF INVENTION  
         [0006]    One object of the invention is to provide an easy-to-maintain rear projection television having a casing with a plurality of maintenance holes for quickly dismounting and repairing components inside the television.  
           [0007]    Another object of the invention is to provide an easy-to-maintain rear projection television that allows repairing without changing the locations of its rear cover or front frame, thereby saving the maintenance labor and simplifying the repair process.  
           [0008]    Furthermore, another object of the invention is to provide an easy-to-maintain rear projection television that includes an electronic unit, an optical module and a set of bulbs that can be replaced without affecting the light projection path.  
           [0009]    In order to achieve the above and other objectives, the rear projection television of the invention includes a casing with a space, at least one maintenance hole and a plurality of modular units. The first maintenance hole is formed through the casing and communicates with the space. A lid covers the first maintenance hole from an outside of the casing. The modular units respectively correspond to the holes. Each modular unit includes an electronic unit, a set of bulbs, and an optical module. A guiding element is mounted in the space to form a channel. A guiding piece is mounted at a periphery of the electronic unit to correspond to the guiding element. The set of bulbs includes a fixed basket and a movable basket screwed onto the fixed basket. The movable basket has a dismountable bulb. When one component inside the casing needs repairing, only the lid corresponding to the component is dismounted to expose the corresponding maintenance hole for the user to repair the target component through the maintenance hole.  
           [0010]    To provide a further understanding of the invention, the following detailed description illustrates embodiments and examples of the invention, this detailed description being provided only for illustration of the invention. dr  
         BRIEF DESCRIPTION OF DRAWINGS  
         [0011]    The drawings included herein provide a further understanding of the invention. A brief introduction of the drawings is as follows:  
           [0012]    [0012]FIG. 1 is a schematic, perspective view of a conventional casing of a rear projection television;  
           [0013]    [0013]FIG. 2 is an exploded view of a conventional casing of a rear projection television;  
           [0014]    [0014]FIG. 3 is a schematic view of a rear projection television;  
           [0015]    [0015]FIG. 4A and FIG. 4B are schematic views of a dismountable electronic unit of an easy-to-maintain rear projection television according to one embodiment of the invention;  
           [0016]    [0016]FIG. 5 is a schematic view of a dismountable tuner of an easy-to-maintain rear projection television according to one embodiment of the invention; and  
           [0017]    [0017]FIG. 6A and FIG. 6B are schematic views of dismountable bulbs of an easy-to-maintain rear projection television according to one embodiment of the invention. 
       
    
    
     DETAILED DESCRIPTION  
       [0018]    Wherever possible in the following description, like reference numerals will refer to like elements and parts unless otherwise illustrated.  
         [0019]    Referring to FIG. 3, an easy-to-maintain rear projector television  2  according to the invention includes a casing  20  and a plurality of module units  21  mounted inside the casing  21 . A space  211  is defined in the casing  21  and communicates with a plurality of maintenance holes formed through the casing  21 .  
         [0020]    Referring to FIG. 4A and FIG. 4B, a guiding element  212  is mounted on an inner bottom  2111  inside the space  211 . The guiding element  212  is a reversed L-shape plate and is vertically mounted on the inner bottom  2111  to form a channel. A first maintenance hole  213  is formed through a rear side of the casing  21  and is covered with a first lid  214 . Referring to FIG. 5, a second hole  215  is formed through a lateral side of the casing  21 . The second maintenance hole  215  is covered with a second lid  216  having a vent hole  2161  as an exit for heat dissipation. Inner elements can be directly repaired or maintained after the second lid  216  is dismounted. Referring to FIG. 6A, a third maintenance hole  217  is formed through a lower part of a front side of the casing  21 . A reflector (not shown) is mounted in a path of image beams projected onto a display screen  22 , so that the image beams reach the display screen  22 .  
         [0021]    Referring to FIG. 4B, control switches needed for image displaying of the rear projection television are modularized into several units including an electronic unit  23 , a light engine  24  and a power supply unit  25 . All the units are mounted inside the space  211 . The electronic unit  23  includes a main board  231  and a plurality of auxiliary modules such as a cable TV tuner  232  inserted in the main board  231 . The electronic unit  23  is mounted inside the casing  21  at a rear end, adjacent to the first maintenance hole  213 . A guiding piece  233  and an ear  234  respectively protrude from a periphery of a bottom of the electronic unit  23 . The guiding piece  233  corresponds to the guiding element  212 . The guiding element  212  of the casing  21  forms a channel to guide the electronic unit into the casing  21 . Then, a crew inserts through the ear  234  to fasten the electronic unit  23  on the inner bottom  2111  of the space  211 . Referring to FIG. 5, the tuner  232  is mounted onto the main board  231  next to the second maintain hole  215 . The second maintenance hole  215  has a diameter through which the tuner  232  passes. The light engine  24  includes an optical module  241  and a set of bulbs  242 . The optical module  241  is mounted at an inner front of the casing  21 . The set of bulbs  242  is mounted adjacent to the third maintenance hole  217 . The optical module  241  includes optical elements such as a spectrometer, a light valve, and a lens. Referring to FIG. 6B, the set of bulbs  242  includes a fixed basket  2421  and a dismountable basket  2422 . A replaceable bulb  2423  is mounted inside the dismountable basket  2422 . The fixed basket  2421  and the optical module  241  form a unitary body. The dismountable socket  2422  and the fixed socket  2421  are combined together via bolts. When the dismountable basket  2422  is dismounted for replacement of the bulb  2423 , the position of the optical module  241  is not changed and the original light path is not changed either. A handle portion  2424  is further formed at a front of the dismountable basket  2422  for convenient dismount of the basket  2422 . Referring to FIG. 4A and FIG. 4B, the power supply unit  25  is mounted at an inner rear of the casing  21  near the first maintenance hole  213 . The power supply unit  25  is a rectangular body. Another ear  251  is formed on the power supply unit  25  near the first maintenance hole  213  for a bolt to penetrate through so as to fasten the power supply unit  25  onto the inner bottom  2111  of the casing  21 . The ears  234 ,  251  are positioned near the maintenance hole  213  to provide a sufficient space for dismount of the bolt by a tool.  
         [0022]    When one component inside the casing  21  needs repairing, only the lid corresponding the component to be repaired needs dismounting so that the component in question is taken from the casing via the corresponding maintain hole. In detail, referring to FIG. 4A and FIG. 4B, when the main board  231  of the electronic unit  23  is to be repaired, the first lid  214  is dismounted and then the crew is loosened. The electronic unit  23  as a whole slides out of the space  211  along the guiding element  212  and the guiding piece  233 . After repairing is completed, the electronic unit  23  is placed to its initial position. When the tuner  232  of the electronic unit  23  is to be repaired, the second lid  216  is dismounted for the user or worker to put his or her hands into the second maintenance hole  215  to take the tuner  232  out for repairing. When the bulb needs to be replaced, the third lid is dismounted to expose the handle portion  2424  of the set of bulbs  242 . The screw fastening the fixed basket  2421  and the movable basket  2422  are loosened to pull out the movable basket  2422  by means of the handle portion  2424 . Then, a new bulb is put in place in the casing. When the power supply unit  25  needs repairing, only the first lid  214  needs to be dismounted and the bolt is loosened to take out and repair the power supply unit  25 .  
         [0023]    As described above, when the electronic unit  23 , bulb  24  or the power supply unit  25  need repairing, only the lid needs to be dismounted an then the above components are taken out through their corresponding holes without changing the location of the rear cover or the front frame. Therefore, the repair processing takes a shorter time and is more convenient. Furthermore, the light projection path is not affected, providing an improved image quality.  
         [0024]    It should be apparent to those skilled in the art that the above description is only illustrative of specific embodiments and examples of the invention. The invention should therefore cover various modifications and variations made to the herein-described structure and operations of the invention, provided they fall within the scope of the invention as defined in the following appended claims.