Abstract:
A driving mechanism for a labeling machine includes a plurality of driving arm assemblies and a gear set. The driving arm assemblies and the gear set are independent and can rotate quickly and are less likely to be worn off, and can drive feeding wheels coupled on axles to rotate concurrently to draw and convey a roll of film. A dust guarding plate is provided to surround a base. The driving mechanism provides secure transmission and simple repair and maintenance.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates to an improved driving mechanism for labeling machine that has a driving arm assembly and a gear set to perform high speed transmission in a simple structure. 
       BACKGROUND OF THE INVENTION 
       [0002]    The driving mechanism of a conventional labeling machine, referring to  FIG. 1 , has a transmission assembly  4   a  consisting of a plurality of pulleys  42   a  coupled with a plurality of linking bars  41   a  and belts  44   a,  and axles  46   a  with an adjustable width to mate a center guide post holding label films of varying dimensions. 
         [0003]    The conventional labeling machine also has a linking belt  48   a  to link a driving wheel  40   a  and a linking pulley  43   a.  A pulley shaft  421   a  is provided to connect to pulleys  42   a  on the linking bars  41   a.  The pulleys  42   a  at two ends of the linking bar  41   a  are transmitted by the belts  44   a.  The pulleys  42   a  on the neighboring linking bars  41   a  are coupled on the pulley shaft  421   a.  Thus the linking bars  41   a  and the belts  44   a  are linked in a selected order. During repair and maintenance, the belts  44   a  cannot be removed and displaced individually. All the belts  44   a  at the front end and rear end have to be disassembled, then assembled and installed again in the selected order. It takes a great deal of time. Moreover, the belts  44   a  between the linking bars  41   a  of the transmission assembly  4   a  have to be wound in a staggered manner to prevent mutual friction. Hence a greater space is required. In addition, the space needed to adjust the tension of the numerous belts  44   a  is limited, the tension of the belts  44   a  vary, transmission speed is uneven and transmission quality is affected. Furthermore, the adjustment mechanism comprising the linking bars  41   a  can only be anchored on the linking pulley  43   a  and the axle  46   a,  and the rest linking bars  41   a  mounted on the pulley shaft  421   a  are suspended. Hence shaking frequently occurs on the linking bars  41   a  that further impacts transmission effect of the belts  44   a.  This results in a shortened life span of the elements. There are still rooms for improvement. 
         [0004]    In short, the driving mechanism of the conventional labeling machine still has many drawbacks in practice, notably: 
         [0005]    1. A greater number of belts are needed. Replacement of the belts is tedious and wastes a lot of manpower and time. 
         [0006]    2. The transmission elements occupy a great deal of space and result in difficult space configuration. 
         [0007]    3. The belts are numerous and their tension is difficult to control, and result in uneven speed. 
         [0008]    4. The transmission elements have many moving hinges. Shaking takes place and steadiness suffers. 
       SUMMARY OF THE INVENTION 
       [0009]    The primary object of the present invention is to overcome the problems of the driving mechanism of the conventional labeling machine such as easy wearing and difficulty of maintenance and replacement of belts. The present invention provides an approach of driving a driving wheel from a power source such as an electric motor and having a driving arm assembly with a gear set located thereon driven by the driving wheel to transmit two axle wheels so that feeding wheels mounted on distal ends of two axles can rotate in opposite directions. Through a movable driving arm, the distance between the two feeding wheels can be adjusted. The gear set on the driving arm assembly has engaged gears which can effectively and rapidly transmit power. Assembly and repair and maintenance also are easier. 
         [0010]    To achieve the aforesaid object, the present invention provides the following features: the gear set is coupled on the movable driving arm assembly with the engaged gears thereof quickly and effectively transmitting power to the feeding wheels on the axles. Maintenance is performed by merely disposing lube oil to the gears regularly. Accuracy can be enhanced, and assembly and repair and maintenance also are easier. 
         [0011]    The invention also provides another feature of deploying individually or jointly. In a joint application that requires multiple feeding wheels, a linking member is provided to connect different driving arm assemblies and axle assemblies. A belt also is provided to connect the transmission wheel and another transmission wheel of another linking member so that the driving arm assemblies are driven concurrently, and the feeding wheels on the axle assemblies are driven to rotate concurrently. 
         [0012]    The present invention provides many benefits, notably: 
         [0013]    1. Using the gear set as the transmission mechanism of the driving arm, power transmission is fast and secured, and can be controlled accurately. Assembly and repair and maintenance also are easier. 
         [0014]    2. Multiple linking members can be connected in series according to requirements to transmit motion between the driving arm assembly and axle assembly. The gears and belts are independent. Replacement is simpler. 
         [0015]    3. Each linking member requires only one belt. Repair and maintenance are easier. 
         [0016]    The foregoing, as well as additional objects, features and advantages of the invention will be more readily apparent from the following detailed description, which proceeds with reference to the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0017]      FIG. 1  is a perspective view of the driving mechanism of a conventional labeling machine. 
           [0018]      FIG. 2  is a perspective view of the labeling machine of the invention. 
           [0019]      FIG. 3  is a perspective view of the driving mechanism of the labeling machine of the invention in a use condition. 
           [0020]      FIG. 4  is a perspective view of the driving mechanism of the labeling machine of the invention. 
           [0021]      FIG. 5  is a front view of the driving mechanism of the labeling machine of the invention. 
           [0022]      FIG. 6  is a rear view of the driving mechanism of the labeling machine of the invention, with the base board removed. 
           [0023]      FIG. 7  is a schematic view of an embodiment of a dual driving approach according to the invention. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0024]    Please refer to  FIGS. 2 ,  3 ,  5  and  6 , the driving mechanism for labeling machine according to the invention is connected to a power source such as an electric motor and includes a driving wheel  3  formed with teeth, a base  4 , a linking member  5 , a driving arm assembly  6 , an axle assembly  7  and a dust guarding plate  8 . 
         [0025]    The base  4  is fastened to a chassis  2  of a labeling machine through an angular post  21  and has at least one boss  40  which has two axle holes  401  running through. 
         [0026]    The linking member  5  is located on the back side of the base  4 , and includes a set of shafts  51 , a set of transmission wheels  52  and a belt  53 . The shaft  51  has one end coupling with the transmission wheel  52  and the other end running through the axle hole  401  of the boss  40  from the rear side of the base  4 . The transmission wheel  52  has teeth formed on the perimeter. The belt  53  is annular and has teeth formed on an inner side and one end coupling on the transmission wheel  52 . 
         [0027]    The driving wheel  3  is coupled with the belt  53  of the linking member  5  and is connected to the power source such as a motor, and engaged with the belt  53  through teeth formed thereon to drive the transmission wheel  52 . 
         [0028]    Referring to  FIGS. 3 through 6 , the driving arm assembly  6  is located on the boss  40  of the base  4 , and includes two corresponding front rocking arms  61 , two corresponding rear rocking arms  62  and one gear set  63 . The gear set  63  may consist of spur gears or helical gears which form enhanced engagement with each other. The gears include two transmission gears  631 , two linking gears  632  and two axle gears  633 . The two front rocking arms  61  have one end run through by two shafts  51  of the linking members  5 . The shafts  51  have other ends coupled with the transmission gears  631 . The two transmission gears  631  engage with each other. The front rocking arms  61  have the other end and the rear rocking arm  62  has one end connecting to the axle portion of the linking gear  632  which in turn engages with the transmission gear  631 . Each axle gear  633  has a fastening hole  6331  formed on the other end of the rear rocking arm  62  to engage with the linking gear  632 . 
         [0029]    The axle assembly  7  is connected to the driving arm assembly  6 , and includes one set of axles  71 , one set of axle adjustment members  72  and one set of feeding wheels  73 . Each axle  71  is coupled in the fastening hole  6331  of the axle gear  633 . Each axle adjustment member  72  is located on a middle portion of the axle  71  to adjust the distance between the two axles  71 . The two axles  71  have respectively a distal end coupling with one feeding wheel  73 . 
         [0030]    Referring to  FIGS. 3 and 5 , the duct guarding plate  8  is a thin plate surrounding the base  4  to prevent external materials and dust from entering the driving arm assembly  6 . 
         [0031]    Referring to  FIGS. 5 and 7 , when the driving wheel  3  is driven by the power source such as an electric motor, it drives the belt  53  of the linking member  5  to rotate the transmission wheel  52 ; the shaft  51  of the transmission wheel  52  transmits the power to the transmission gear  631  at one end of the front rocking arm  61  at the front side of the base  4 ; the transmission gear  631  drives another transmission gear  631  at one end of another front rocking arm  61  so that the two transmission gears  631  rotate concurrently in opposite directions; then the two rotating transmission wheels  631  drive the engaged linking gears  632  that are overlapped with the front and rear rocking arms  61  and  62 ; the linking gears  632  further drive the axle gears  633  at the other end of the rear rocking arms  62 , and the axles  71  of the axle gears  633  also are driven and rotate; therefore, the feeding wheels  73  at the other end of the axles  71  rotate concurrently in opposite directions. 
         [0032]    The driving mechanism of the invention may be deployed independently or in a joint manner. When used in the joint manner, two sets of the same driving mechanisms can be coupled together to allow the labeling machine  1  to operate in a dual driving fashion. In such a circumstance, a set of idler pulleys  54  are installed on the base  4 , and the belt  53   a  of the linking member  5   a  of the second set is adjusted. No adjustment is required on the first set. The belt  53  is coupled with one transmission wheel  52  and driving wheel  3 . But the belt  53   a  of the linking member  5   a  of the second set is coupled with another transmission wheel  52  of the linking member  5  of the first set and another transmission wheel  52   a  of the linking member  5   a  of the second set at the same side. The belt  53   a  of the linking member  5   a  of the second set is pushed by the idler pulley  54  to maintain the belt  53   a  at a desired tension. Then the two linking members  5  and  5   a  can be driven concurrently by the driving wheel  3 . As previously discussed, when the transmission wheels  52  and  52   a  of the two linking members  5  and  5   a  rotate, the two driving arm assemblies  6  and  6   a  also are driven concurrently.