Patent Publication Number: US-7905485-B2

Title: Paper feeding apparatus and paper feeding method thereof with a plurality of force units with fluid-supply devices

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a paper feeding apparatus and a paper feeding method using the same, and in particular to a paper feeding apparatus with a cylinder device for outputting equal feeding force. 
     2. Description of Prior Art 
     Computers are widely used in the modern life and printers are popular outputting machines for outputting data stored in a computer. Consumers choose a printer depending on the printing quality. Furthermore, the considerations such as printing rate, printing stability and printing reliability are also important criteria when end-users buy a printer. High printing stability relies on a well-controlled feeding mechanism. The feeding mechanism has many functions, such as drawing paper from different trays and driving the single piece of paper to move by a wheel. The paper is fed into the printer and the selected data is printed on the paper. 
     However, the wheels are connected on the axle in the traditional feeding mechanism. Due to the errors of manufacturing or assembling, the wheels may output force with different quantities. The paper is driven by different forces so that the parts of paper can not move in the same speed and then paper jams occur. A flexible axle has been developed for solving the problem. The flexible axle is simply made of elastic material, but the correcting range is too small to compensate efficiently for the different forces. 
     Therefore, in view of this, the inventor proposes the present invention to overcome the above problems based on his expert experience and deliberate research. 
     SUMMARY OF THE INVENTION 
     The primary object of the present invention is provided for a paper feeding apparatus and a paper feeding method using the same. According to Pascal&#39;s principle of hydraulic pressure, each force unit of the paper feeding apparatus can output the same component on a corresponding paper feeding wheel so that paper is driven to feed in a machine by the same feeding friction. 
     In order to achieve the above object, the present invention provides a paper feeding apparatus comprising: a fluid-supply device; a connecting pipe communicating with the fluid-supply device; and a plurality of force units connecting to the connecting pipe, each force unit having a pressing wheel on one end thereof; wherein each pressing wheel operates in coordination with a paper feeding wheel for feeding paper. 
     In order to achieve the above object, the present invention further provides a paper feeding apparatus comprising: a fluid-supply device; a connecting pipe communicating with the fluid-supply device, wherein the connecting pipe has a first auxiliary pipe and a second auxiliary pipe; a pressing module connecting to the first auxiliary pipe, wherein the pressing module has a plurality of first force units; and a second force unit connecting to the second auxiliary pipe, wherein the first force units and the second force unit individually has a pressing wheel; wherein each pressing wheel operates in coordination with a paper feeding wheel for feeding paper. 
     In order to achieve the above object, the present invention still further provides a paper feeding method comprising: providing a paper feeding unit having a plurality of paper feeding wheels, and assembling a paper feeding apparatus on the paper feeding unit, the paper feeding apparatus comprising: a fluid-supply device; a connecting pipe communicating with the fluid-supply device; and a plurality of force units connecting to the connecting pipe, each force unit having a pressing wheel on one end thereof wherein the fluid-supply device supply a fluid to the force units thought the connecting pipe; wherein each pressing wheel operates in coordination with the corresponding paper feeding wheel for feeding paper; wherein the force units output equal force so that the pressing wheels apply the same force to the corresponding paper feeding wheels in order to form equal friction force for feeding paper. 
     In the present invention, Pascal&#39;s principle of hydraulic pressure and the equal cross-section areas are used for construct the paper feeding apparatus so that each of pressing wheels outputs the same components on corresponding paper feeding wheel. Therefore, the problems of “paper jam” for the reasons of imprecision of the assembly are solved. 
     In order to better understand the characteristics and technical contents of the present invention, a detailed description thereof will be made with reference to the accompanying drawings. However, it should be understood that the drawings and the description are illustrative but not used to limit the scope of the present invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic view showing the paper feeding apparatus according to the present invention. 
         FIG. 2  is a simplified view showing the paper feeding apparatus in usage according to the present invention. 
         FIG. 3  is a simplified view showing the second embodiment of the paper feeding apparatus according to the present invention. 
         FIG. 4  is schematic representation showing the third embodiment of the paper feeding apparatus according to the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Please refer to  FIGS. 1 and 2 , the invention discloses a paper feeding apparatus  1  and a paper feeding method using the same. The paper feeding apparatus  1  is used for achieving a better paper-feeding quality. The paper feeding apparatus  1  has a fluid-supply device  10 ; a connecting pipe  11  communicating with the fluid-supply device  10 ; and a plurality of force units  12  connecting to the connecting pipe  11 . Furthermore each force unit  12  has a pressing wheel  120  on one end thereof. The fluid-supply device  10  provides a fluid to the connecting pipe  11  and force units  12 . The fluid-supply device  10 , for example, can be a container to preserve the fluid and supply it to the connecting pipe  11 . The paper feeding apparatus  1  is assembled on a printer or other device with a paper feeding mechanism. Depending on the fluid, a fluid pressure is generated in the connecting pipe  11  and force units  12 . 
     The fluid-supply device  10  provides a fluid which can be a liquid or a gas and the fluid contained in the connecting pipe  11  outputs a hydraulic pressure P to drive the force units  12  to generate a force. In other words, the force units  12  can output force F by transforming the hydraulic pressure of the fluid. The fluid-supply device  10  further has an inlet valve  101  which is applied for filling or compensating the fluid in the fluid-supply device  10 . 
     Furthermore, the connecting pipe  11  is an empty tube within which the fluid flows and forms the fluid pressure P. The connecting pipe  11  has a plurality of auxiliary pipes  110  and the force units  12  connect to the auxiliary pipes  110 . The hydraulic pressure P is generated as the fluid flows inside the connecting pipe  11  and auxiliary pipes  110 . 
     The force units  12  are used for transforming the hydraulic pressure P into a force. In the embodiment, the force units are cylinders with equal cross-section areas so that the forces generated by the force units  12  can be equal. Concerning Pascal&#39;s principle, pressure applied to an enclosed fluid is transmitted undiminished to every part of the fluid, as well as to the walls of the container. Therefore, equal fluid pressure is generated on the force units  12  because of the fluid in the enclosed system including the fluid-supply device  10 , connecting pipe  11  and auxiliary pipes  110 . On the condition that the force units  12  have equal cross-section areas, the force units  12  can output equal force F on the corresponding pressing wheel  120 . However, the force unit  12  further has a controlling valve  121  to output equal force F on the corresponding pressing wheel  120  even if the force units  12  does not have equal cross-section areas due to the imprecision of manufacturing or the other reasons shown in  FIG. 4 . 
     The pressing wheel  120  of the force units  12  is rotatably pivoted on the force units  12 . The pressing wheels  120  apply a force to the paper feeding wheel  20  and operate in coordination with the paper feeding wheel  20  so as to feed paper. The corresponding pressing wheel  120  and the paper feeding wheel  20  rotate in opposite directions, moving the paper by means of friction. 
     Please refer to  FIGS. 1 and 2 , the application of paper feeding apparatus  1 . The paper feeding apparatus  1  is assembled on a printer or the like and the pressing wheels  120  of the paper feeding apparatus  1  are corresponding to the paper feeding wheels  20 . The fluid generates the hydraulic pressure P in each of the force units  12  because of the enclosed tube system (i.e. connecting pipe  11  and auxiliary pipes  110 ). Therefore, the pressing wheels  120  apply a force to the paper feeding wheels  20  with equal value of force because the force units  20  output equal force. In other words, there is equal degree of friction between the corresponding pressing wheels  120  and the paper feeding wheels  20  so that the paper can be fed in smoothly. 
     Accordingly, user can send paper  30  between the corresponding pressing wheels  120  and the paper feeding wheels  20  and paper  30  is fed into the printer smoothly with the same velocity. The method for using the paper feeding apparatus  1  is assembling the paper feeding apparatus  1  on a paper feeding unit, for example, a printer. The fluid in the paper feeding apparatus  1  performs the equal hydraulic pressure P everywhere depending on Pascal&#39;s principle. In case of the force units  12  has equal cross-section area or controlled by the controlling valve  122 , the force units  12  can output equal degree of force. At last, there is equal degree of friction between the corresponding pressing wheels  120  and the paper feeding wheels  20  so that the paper can be fed. Accordingly, the problem of paper jam in the traditional printer is solved because of the equal paper feeding force. Furthermore, depending on different kinds of paper  30 , the fluid-supply device  10  can provide the fluid in corresponding hydraulic pressure P. Therefore, the force units  12  can output different force so that the paper can be fed more uniformly. 
     Please refer to  FIG. 3 , the second embodiment is shown. In the second embodiment, there are different numbers of force units  12  disposed on the opposite end of connecting pipe  11 . Two first force units  12 A disposed on the right end of the connecting pipe  11  are constructed as a pressing module  1 ′. The pressing module  1 ′ further has connecting tube  11 A connected to the two first force units  12 A. Similarly, the paper feeding apparatus  1  has a fluid-supply device  10  and a connecting pipe  11  communicating with the fluid-supply device  10 . The fluid-supply device  10  further has an inlet valve  101  which is applied for filling or compensating the fluid in the fluid-supply device  10 . The connecting pipe  11  has a first auxiliary pipe  110 A and a second auxiliary pipe  110 B. The connecting tube  11 A of the pressing module  1 ′ connects with the first auxiliary pipe  110 A and the second auxiliary pipe  110 B connects to a second force unit  12 B. When the fluid is supplied by the fluid-supply device  10 , the fluid generates equal hydraulic pressure P in the connecting pipe  11 , the first auxiliary pipe  110 A, the second auxiliary pipe  110 B and the connecting tube  11 A. Therefore, each first and second force units  12 A,  12 B can output equal degree of force so that there is equal degree of friction between the corresponding pressing wheels and paper feeding wheels. However, the number of the force unit is taken for example, but not to restrict to the present invention. Moreover, the first and second force units  12 A,  12 B have the same features with the first embodiment, for example the controlling valve  121 . 
     To sum up, the present invention has the following advantages:
     1. By transmitting the equal hydraulic pressure to the equal degree of force, the paper feeding apparatus operates with Pascal&#39;s principle so that the friction is equal between the corresponding pressing wheel and paper feeding wheel.   2. There can be different numbers of pressing units on the two sides of the connecting pipe to construct as a pressing module so that the paper feeding apparatus can be applied for more different applications.   

     Although the present invention has been described with reference to the foregoing preferred embodiment, it will be understood that the invention is not limited to the details thereof. Various equivalent variations and modifications may occur to those skilled in this art in view of the teachings of the present invention. Thus, all such variations and equivalent modifications are also embraced within the scope of the invention as defined in the appended claims.