Abstract:
A manually guided vehicle capable of working on rails is described. The manually guided vehicle has a frame, a set of moving wheels, a guiding wheel, and a supporting device. The moving wheels provide the manually guided vehicle with the capability of moving on rails or on the ground. The guide wheel provides the manually guided vehicle with the capability of moving along rails. The guide wheel can be raised to move the manually guided vehicle off of the rails directly. The supporting device provides double direction forking and horizontal rotating capabilities. The rails include a U-type guiding rail to limit the guide wheel to motion thereon. The manually guided vehicle further has a laser pointer to indicate the position of the manually guided vehicle and further cooperates with position labels stuck on working stations along the rail to enhance the parking position accuracy of the manually guided vehicle.

Description:
FIELD OF THE INVENTION  
         [0001]    The present invention relates to a manually guided vehicle and especially to a manually guided vehicle capable of working on rails.  
         BACKGROUND OF THE INVENTION  
         [0002]    Automated guided vehicles (AGVs) perform in an important role of material transportation in an automatic factory. Most of the automated guided vehicles are rail guided vehicles (RGVs). The RGV not only provides an efficient material transportation for the automatic factory and the automatic warehouse but also provides a powerful transportation for movement of heavy goods, weighing perhaps more than a hundred tons.  
           [0003]    If the factory layout is changed, the rail will be modified to fit the new layout. Generally speaking, although a factory is highly automated, the rail guided vehicle still cannot reach all the working areas of the factory due to the rail layout limitation. Therefore, manually guided vehicles are still utilized in both ordinary and automated factories. A manually guided vehicle is especially utilized in a factory whose rails are not established, in a factory whose rails have been damaged, or in places lacking rails in a factory. The manually guided vehicle provides an important capability with highly flexible operations.  
           [0004]    Due to the rapid progress of optical technology and semiconductor technology, liquid crystal displays (LCD) have been widely applied in electrical products. From a LCD monitor having a small display size to a LCD television having a large display size, the LCD size is extending. More and more people choose to purchase large size LCD televisions.  
           [0005]    LCD manufacture requires a very clean environment, such as a clean chamber, to enhance the yield rate and quality level thereof. A cassette is utilized to protect and isolate the LCDs during transportation within a factory. Therefore, the size of the LCD cassette is increased according to the size of the LCD. The large size LCD cassette is very difficult to move, especially in a new factory without an established RGV system. Hence, the quality of the LCD is difficult to control in the initial stage of the new factory, because that the LCD cassettes are loaded and unloaded by manpower.  
         SUMMARY OF THE INVENTION  
         [0006]    One object of the present invention is to provide a manually guided vehicle capable of working on rails to transport materials and storage boxes thereof  
           [0007]    Another object of the present invention is to provide a manually guided vehicle that possesses a turntable and a telescopic fork to load and unload a LCD cassette in two directions, left and right, of the manually guided vehicle,  
           [0008]    Yet another object of the present invention is to provide a manually guided vehicle that possesses a storable guide wheel that allows convenient entrance and exit from the rails.  
           [0009]    Still another object of the present invention is to provide a manually guided vehicle with a laser pointer to improve a working position accuracy of the manually guided vehicle.  
           [0010]    To achieve these and other advantages and in accordance with the object of the invention, the present invention provides a manually guided vehicle capable of working on rails. The manually guided vehicle includes a frame, a handle, a set of moving wheels, a guide wheel, and a supporting device. The moving wheels enable the manually guided vehicle to move on rails or on the ground. The guide wheel limits the manually guided vehicle when moving on rails and the guide wheel can be raised to allow the manually guided vehicle to be pushed off the rails directly. The supporting device is disposed above the frame to provide functions of double side forking and horizontal rotation.  
           [0011]    The rails further include a U-type guiding rail and the guide wheel clamps the U-type guiding rail to limit the manually guided vehicle to movement on the rails. The supporting device further has a telescopic fork for double side forking and a turntable for rotating along a horizontal surface.  
           [0012]    The manually guided vehicle according to the present invention further utilizes a laser pointer to indicate a position of the manually guided vehicle. The laser pointer cooperates with a position label attached on a work station to indicate a parking position of the manually guided vehicle so that the parking position accuracy of the manually guided vehicle can be enhanced.  
           [0013]    The position label includes a dark ground and a light reflection line. While the laser pointer emits a red laser beam, the position label having a blue ground and a white reflection line is detected to show the position of the laser beam clearer.  
           [0014]    The manually guided vehicle according to the present invention further has a handle for moving the manually guided vehicle and a parking device for parking and fixing the manually guided vehicle. The manually guided vehicle according to the present invention is preferred for transport of a liquid crystal display cassette.  
           [0015]    Hence, the manually guided vehicle according to the present invention not only works on rails but also works on the ground of the factory so that the work area of the manually guided vehicle is efficiently extended. The manually guided vehicle according to the present invention further provides a laser positioning function, a double side forking function, and a function of directly pushing the manually guided vehicle of the rails from one side of the rails. Therefore, the manually guided vehicle according to the present invention enhances the LCD transportation convenient ability and reliability for the LCD manufacture especially during a test run period. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0016]    The foregoing aspects and many of the attendant advantages of this invention will be more readily appreciated as the same becomes better understood by reference to the following detailed description, when taken in conjunction with the accompanying drawings, wherein:  
         [0017]    [0017]FIG. 1 is a schematic view of a manually guided vehicle capable working on a rail according to the present invention and rails;  
         [0018]    [0018]FIG. 2A is a front view of the manually guided vehicle capable working on a rail according to the present invention;  
         [0019]    [0019]FIG. 2B is a top view of the manually guided vehicle capable working on a rail according to the present invention; and  
         [0020]    [0020]FIG. 3 is schematic view of a laser pointer of the manually guided vehicle and a work station with a position label. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0021]    The following description is the best presently contemplated mode of carrying out the present invention. This description is not to be taken in a limiting sense but is made merely for the purpose of describing the general principles of the invention. The scope of the invention should be determined by referencing the appended claims.  
         [0022]    [0022]FIG. 1 is a schematic view of a manually guided vehicle capable of working on rails according to the present invention and rails. The manually guided vehicle  100  includes a frame  104 , a supporting device  106  disposed on the frame  104 , and a handle  102  disposed on the rear side of the frame  104 . The handle  102  allows a user to push the manually guided vehicle  100 . A cassette  120  is disposed on the supporting device  106  to hold substrates, semifinished products, and LCD products for transport to a work station  110 . The cassette  120  provides functions of protection and isolation for these substrates, semifinished products, and LCD products.  
         [0023]    When the manually guided vehicle  100  is utilized to transport the cassette  120  to the work station  110  and place the cassette  120  on the work station  110 , the manually guided vehicle  100  is moved along a rail  130  and a rail  140  until the manually guided vehicle  100  arrives at the position of the work station  110 . The rail  130  is flat rail for supporting the manually guided vehicle  100  moving thereon. The rail  140  is an anti-lateral movement rail to prevent the manually guided vehicle  100  from derailing.  
         [0024]    Referring to FIGS. 2A and 2B simultaneously. FIG. 2A is a front view of the manually guided vehicle capable of working on a rail according to the present invention and FIG. 2B is a top view of FIG. 2A. A lift control device  210 , a telescopic fork control device  220 , a telescopic fork fixing device  280 , a parking device  290  and handles  102  are disposed on the rear side of the frame  104  of the manually guided vehicle  100  for a user to conveniently control the manually guided vehicle  100 .  
         [0025]    The supporting device  106  having a telescopic fork  230  and a turntable  240  is disposed on the front end of the frame  104 . The moving wheels  250  are assembled on the bottom of the frame  104  so that the manually guided vehicle  100  can move on the rail  130  and the rail  140 , as well as the ground anywhere in the factory. A guide wheel  260  clamps on the rail  140 , such as a U-type guiding rail, to constrain the manually guided vehicle  100  to movement on the rail  130  and the rail  140  and prevent the manually guided vehicle  100  from derailing. The manually guided vehicle  100  further includes a laser pointer  270  to indicate an accurate position of the manually guided vehicle  100 . A laser pointer  270  is coordinated with a position label  310  (see FIG. 3) to further improve the position accuracy of the manually guided vehicle  100 ,  
         [0026]    The following description details each element of the manually guided vehicle  100  and functions thereof. The description is illustrative of the present invention rather than limiting of the present invention. When the manually guided vehicle  100  is moving along the rail  130  and the rail  140 , the guide wheel  260  clamps the rail  140 , the U-type guiding rail, to constrain the manually guided vehicle  100  moving along the rail  130  and the rail  140  and prevent derailing. When the manually guided vehicle  100  wants to move on the ground and leave the rail  130  and the rail  140 , the guide wheel  260  is raised so as to release the rail  140 , the U-type guiding rail. Accordingly, the manually guided vehicle  100  easily leaves the rail  130  and the rail  140  from a side of the rail  130 . A preferred moving wheel  250  is made of a non-metal material, such as plastic or rubber, so that the manually guided vehicle  100  may easily anywhere move on the ground of a factory. However, a metal moving wheel is still within the spirit and scope of the present invention.  
         [0027]    The manually guided vehicle  100  can efficiently move in the factory to deliver materials, semifinished product, and LCD product to anyplace in the factory so as to efficiently support the manufacture of the production line.  
         [0028]    When the LCD panel is in a test run or in mass production, the manually guided vehicle  100  is normally utilized to delivery the cassette  120 . The cassette  120  stores and isolates the substrate and the semifinished product to transfer conveniently the same to another working station. In transporting a LCD cassette, the manually guided vehicle  100  is pushed to a work station  110  (see FIG. 1) along the rail  130  and the rail  140 . The manually guided vehicle  100  is then stopped at a predetermined position of the work station  100  when the operator steps on the parking device  290 . At that moment, the operator tuns on the telescopic fork fixing device  280  and then loads or unloads the cassette  120 .  
         [0029]    If the cassette  120  is unloaded from the work station  110 , that is to say, the cassette  120  is removed from the work station  110 , the operator first moves the telescopic fork  230  with the telescopic fork control device  220 . The telescopic fork  230  provides a double direction forking function, that is to say, the telescopic fork  230  can fork the cassette  120  deposited on the work station from both left side and right side of the manually guided vehicle  100 . A conventional manually guided vehicle has to turn the vehicle  180  degrees when a cassette deposited on another side is to be loaded onto or unloaded from the manually guided vehicle. The manually guided vehicle  100  according to the present invention efficiently improves the operation inconvenience incurred by a conventional manually guided vehicle.  
         [0030]    After the telescopic fork  230  has been extended to the bottom of the cassette  120 , the lift control device  210  is turned to move the supporting device  106  up a predetermined height. Therefore, the cassette  120  is separated from the work station  110 . The telescopic fork control device  220  is turned for returning the telescopic fork  230  until the telescopic fork  230  is restored to the center position of the supporting device  106 . Then, the telescopic fork  230  is locked by the telescopic fork fixing device  280  to fix the telescopic fork  230  and the turntable  240 .  
         [0031]    If the cassette  120  is unloaded onto the work station  110 , that is to say, the cassette  120  is removed from the manually guided vehicle  100  to the work station  110 , the operator first unlocks the telescopic fork fixing device  280  and then moves the telescopic fork  230  with the cassette  120  toward the work station  110  by the telescopic fork control device  220 . After the telescopic fork  230  has been extended to the top position of the work station  110 , the lift control device  210  is turned to move the supporting device  106  down the predetermined height. Therefore, the cassette  120  is placed on the work station  110  and then the telescopic fork  230  is moved down more to separate from the cassette  120 . Subsequently, the telescopic fork control device  220  is turned for returning the telescopic fork  230  until the telescopic fork  230  is restored to the center position of the supporting device  106 .  
         [0032]    If the cassette  120  has to be placed on a new work station opposite to the work station  110 , that is, on the other side of the manually guided vehicle  100 , the manually guided vehicle  100  according to the present invention can easily turn the cassette  120  to face the new direction and place the cassette  120  onto the new work station opposite to the work station  110  by way of turning the turntable  240  about  180  degrees along a horizontal surface.  
         [0033]    The manually guided vehicle  100  according to the present invention further includes the laser pointer  270  to enhance the position accuracy thereof. FIG. 3 is schematic view of a laser pointer of the manually guided vehicle and a work station with a position label. The laser pointer  270  emits a laser beam, such as a visible red laser beam, to indicate the position of the manually guided vehicle  100 . As the manually guided vehicle  100  is moving along moving direction  340 , the laser beam emitted by the laser pointer  270  is synchronized moving along the moving direction  340 . Furthermore, the laser pointer  270  cooperates with the position label  310  stuck on the work station  110  so as to manifest the accurate position of the manually guided vehicle  100 .  
         [0034]    The position label  310  combines a dark label ground  320  with a light reflection line  330 . The label ground  320  is preferably blue and the reflection line  330  is preferably white when the laser beam is a visible red color. Hence, the red laser beam can distinguish the white reflection line  330  so that the laser pointer  270  can precisely indicate the position of the manually guided vehicle  100  and the operator can park the manually guided vehicle  100  more accurately according to the indications of the laser pointer  270  on the position label  310 . The manually guided vehicle  100  according to the present invention can efficiently enhance the working position accuracy to improve the poor position recognition capacity of the conventional manually guided vehicle.  
         [0035]    The lift control device  210  and the telescopic fork control device  220  utilize manual wheels to control the supporting device  106  and the telescopic fork  230 . However, the lift control device  210  and the telescopic fork control device  220  are not limited to the manual wheels. A power control device, such as an electrical power control device or a similar control device, is within the spirit and scope of the present invention. Further, the parking device  290  can directly link with the moving wheel  250  or utilize a stopping wheel to stop the manually guided vehicle.  
         [0036]    As is understood by a person skilled in the art, the foregoing preferred embodiments of the present invention are illustrative of the present invention rather than limiting of the present invention. It is intended that various modifications and similar arrangements be included within the spirit and scope of the appended claims, the scope of which should be accorded the broadest interpretation so as to encompass all such modifications and similar structures.