Abstract:
A conveying apparatus. The apparatus includes an air-cooled hydraulic driving unit, a hydraulic motor, a conveyor and a connecting element. The air-cooled hydraulic driving unit includes a hydraulic pump, an electrical motor, pipes, a flow regulator, and a cooling fan. The cooling fan is adapted for low temperature environment and does not require complicated pipes, so that the conveying apparatus of the present invention can be flexibly combined with other devices or applied to various processes.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a conveying apparatus and, more particularly, to a conveying apparatus driven by an air-cooled hydraulic driving unit, such apparatus may further include a set of rollers used for collecting adhesive or rubber film in the processes of manufacturing adhesive tapes or tires. 
     2. Description of Related Art 
     Industrially, conveyors in processes are used to transport raw materials or products. For example, in the process of manufacturing rubber sheet, material is transported by a conveyor after being produced and cooled, and eventually collected by collecting rollers installed next to the conveyor. For most situations, the conveyor is often disposed in a fixed position to fit with the main production machine. The immobility of such conveyors is a shortcoming for the layout of such a plant. 
     Additionally, in order to improve the precision of transport speed, most conveyors are driven by hydraulic motors instead of electric motors. However, the oil of such hydraulic motors is mostly cooled by a liquid cooling medium, which needs a highly efficient cooling device to cool the liquid medium. In this way, such arrangement is apparently limiting the flexibility of the conveyors. 
     Therefore, it is desired to provide an improved conveying apparatus to mitigate and obviate the aforementioned problems. 
     SUMMARY OF THE INVENTION 
     The object of the present invention is to provide a conveying apparatus which can be easily moved and disengaged to be suitable for different production processes. 
     Another object of the present invention is to provide a conveying apparatus which is flexibly used in sheet material collection. 
     To achieve these objects, the conveying apparatus of the present invention includes an air-cooled hydraulic driving unit, a hydraulic motor, a conveyor and a connecting element. 
     The air-cooled hydraulic driving unit is composed of a hydraulic pump, an electrical motor, a plurality of pipes, a flow regulator, and a cooling fan. The flow regulator can be a manual-control valve or an electrical-control valve. The hydraulic motor can be driven by the hydraulic pump of the air-cooled hydraulic driving unit. The conveyor includes a main roller driven by the hydraulic motor, at least one passive roller, and a belt mounted around the main roller and the passive roller. The connecting element can be, for example, a coupling used for connecting the hydraulic motor and the main roller of the conveyor. 
     The air-cooled hydraulic driving unit may further include a manometer and a three-way valve to stop the hydraulic driving unit or to make the belt operate in the opposite direction. 
     The cooling fan and the electrical motor of the air-cooled hydraulic driving unit can simultaneously start up by connecting electrically in parallel, and the power is generally supplied with 3-phase AC of 220 V and 3.5 A. 
     The above apparatus may combine with at least one set of rollers disposed upon the belt to form a film products collector. The one set of rollers primarily includes a supplying scroll holding liner sheets, and at least one collecting scroll for rolling up the film product overlaid on the liner sheets. The supplying scroll can be regulated by a tension element, and the collecting scroll can be elevated by two supporting devices at two ends thereof. 
     Additionally, a tension roller may be disposed between the supplying scroll and collecting scroll to keep the liner sheets stretched taut. The film product is laid out over the conveyor belt by passing it in between a pressing roller and the conveyor belt after it is produced from a main production machine. 
     Other objects, advantages, and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of an embodiment the present invention; 
     FIG. 2 is a perspective view of the driving unit of the embodiment in FIG. 1; and 
     FIG. 3 is a perspective view of another embodiment of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     With reference to FIG. 1, there is shown a perspective view of the conveying apparatus of the present invention, wherein a conveyor  10  includes a frame  11 , and a main roller  12  and a passive roller  13  mounted on the frame  11 . Around the main roller  12  and the passive roller  13 , a belt  14  is mounted to transport objects thereon. The main roller  12  can be driven to roll by a hydraulic motor  20 , and connects with each other by a coupling. The hydraulic motor  20  is driven by oil in pipes  43 ,  44  of a hydraulic driving unit  30 . 
     The hydraulic driving unit  30  is shown in FIG. 2, which includes a hydraulic,pump  31 , an electrical motor  32 , an oil tank  33 , and a cooling fan  50  for cooling the oil. The oil tank  33 , with an inlet  331 , a discharge-opening  332  and a window  333  to inspect the oil level, can store and supply oil to the hydraulic driving unit  30 . The cooling fan  50  includes a set of blades  51 , a driving motor  52  and a cooling circuit  53 . 
     The oil drawn from the oil tank  33  enters into the hydraulic pump  31  through an oil pipe  41 , and flows out through an oil pipe  42 . A manual-control flow regulator  421  is installed on the oil pipe  42  to adjust the oil flow in the pipe  42  and therefore control the speed of the belt  14 . An electrical-control valve can be used instead of the manual-control flow regulator  421 . A manometer  422  for monitoring the oil pressure and a three-way valve  423  for changing the flowing direction of the oil are installed next to the flow regulator  421 . The three-way valve  423  is operated by wrenching a handle up, down or to the middle position, so as to control the running direction of the belt  14 , or make it stop running. 
     The oil from an oil pipe  43  enters into the hydraulic motor  20  shown in FIG. 1, and then flows back to the three-way valve  423  through an oil pipe  44 . The circulating oil eventually flows back to the oil tank  33  through an oil pipe  45 . In general, the temperature of the circulating oil may gradually rise to about 60-90° C. after a period of working time. Therefore, a part of the oil drawn from the hydraulic pump  31  is cooled by transporting to the cooling circuit  53  of the cooling fan  50  through an oil pipe  46 . The cooled oil, at a temperature of about 26° C., is then sent back to the oil tank  33  through an oil pipe  47 . 
     In this embodiment, the oil pipes  41 ,  42 ,  45 ,  46 , and  47  are metal pipes, and oil pipes  43 ,  44  are high pressure rubber hoses. Additionally, the driving motor  52  of the cooling fan  50  and the electrical motor  32  are electrically connected in parallel to enable simultaneous start up, and the power is generally supplied by 3-phase AC of 220 V and 3.5 A. 
     FIG. 3 is a view of combining the above apparatus with two sets of rollers  60 ,  60 ′ disposed upon the conveying belt  14  to form a film product collector, which is suitable for processes of, for example, collecting rubber sheets or textile products, etc. 
     One set of the rollers  60 , for example, primarily includes a supplying scroll  61  rolling up liner sheets  80 , and a collecting scroll  63  for collecting and rolling up the film product  70  overlaid on the liner sheet  80 . The supplying scroll  60  can be stopped by a tension element  611 , and the collecting scroll  63  can be supported by two regulating rods  631 ,  631 ′ at two ends thereof. The two regulating rods  631 ,  631 ′ have respective slots  632 ,  632 ′, enabling the collecting scroll  63  to slide up and down within the slots  632 ,  632 ′ and fixed therein. Additionally, a tension roller  62  may be disposed between the supplying scroll  61  and the collecting scroll  63  for keeping the liner sheets  80  stretched taut. The film product  70  can become horizontally flat and line on the conveying belt  14  by pressing it between a pressing roller  64  and the belt  14 . 
     After being produced and then continually transported through the cooling roller  90 , the film product  70  is pressed by the pressing roller  64  to lie the film  70  on the belt  14 . The plastic liner sheet  80  around the supplying scroll  61  is kept in tension by the tension roller  62 , and rolled around the collecting scroll  63 . After being sent underneath the pressing roller  64 , the film product  70  is overlaid and rolls together with the liner sheet  80  on the collecting scroll  63  which was put down into contact with the conveying belt  14  by moving along the two slots of the two supporting devices  631 ,  631 ′. On the other hand, the collecting scroll  63  can freely slide up along the two slots, when the size of the roll of the film product  70  together with the liner sheet  80  is increased. In this way, the film product  70  covered with the liner sheet  80  is collected around the collecting scroll  63 . 
     For most batchwise processes such as the one described above, the conveying apparatuses often lie idle when the production line stops working, if they can&#39;t be easily moved. However, the conveying apparatus of. the present invention can overcome such problem by cooling the oil with the cooling fan  50 , because no complicated piping for transporting cooling liquid and its heavy weight coding tank are required. It&#39;s understandable that the effect of cooling air is unsurpassed to use the conveying apparatus of the present invention in low-temperature environment, or connect with a small-sized conveyor for being easily moved. 
     Furthermore, the conveying apparatus  10  can be adapted to other devices or rollers to promote or increase its working capability such as the aforementioned film product collector. 
     Although the present invention has been explained in relation to its preferred embodiment, it is to be understood that many other possible modifications and variations can be made without departing from the spirit and scope of the invention as hereinafter claimed.