Abstract:
A film loading method of an image forming apparatus, includes: loading an endless film which was stored in a container box, using at least two support members, to a film frame of the image forming apparatus, wherein the film is supported by the support members in a different form with respect to a condition of the film when loaded and fitted to the film frame. The support members are initially stored in the container box and serve as a packaging member for use in transporting and storing the film. The support members are attached to respective portions of the film frame and guide the film to be loaded and fitted onto the film frame. The film frame includes holding rollers, and the support members are attached to the respective portions of the film frame, coaxially with the holding rollers.

Description:
The present application is a Continuation of U.S. application Ser. No. 10/448,293, filed on May 30, 2003 now U.S. Pat. No. 7,336,917. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a film loader for an image forming apparatus, and more particularly to the loading of a film such as a photosensitive film, an intermediate transfer film, a transfer film, a carrier film or a fixing film to be used in each portion of an electrophotographic printer. 
     2. Description of the Related Art 
     A conventional film loading method includes steps of detaching a film frame from a main body of an image forming apparatus, placing the film frame vertically, loading a photosensitive film into the film frame longitudinally from above, and thereafter attaching the film frame to the main body of the image forming apparatus. 
       FIG. 12  is a schematic view of the film loader with a photosensitive film loaded in the related art. In  FIG. 12 , reference numeral  1  denotes the photosensitive film, reference numeral  5  denotes the film frame, and reference numerals  6   a  and  6   b  denote holding rollers for holding the photosensitive film  1 . In loading the photosensitive film  1 , while the photosensitive film  1  is supported by an operator&#39;s hand in a state where the film frame  5  is drawn horizontally from the main body not shown, the photosensitive film  1  is aligned with the film frame  5  and the holding rollers  6   a  and  6   b  and then loaded into the film frame  5 . 
     In this operation, the operator conducts the replacement of the photosensitive film while the operator touches only an inner backing portion of the film or end portions of the film surface (both of annular edge portions), but does not touch the surface of the photosensitive film or wears globes. 
     In the related art where the film frame is vertically placed, it is necessary to detach the film frame from the main body of the image forming apparatus. The film frame is a heavy substance, and there arises problems in the respects of operability and maintenance. 
     Also, in the related art where the photosensitive film is loaded into the film frame horizontally drawn from the main body of the apparatus by an operator&#39;s hand, it is impossible to repair a slack in the central part of the film when loading, causing a bend or a crack in the photosensitive film, resulting in a problem that the photosensitive film is damaged on the surface and unusable. 
     Particularly, the latest image forming apparatus with very high processing speed has a peripheral length of the photosensitive film of 2 m or more, and a length in the depth direction (drawing direction in loading) of 60 cm or more, whereby some skills are required to load the film into the film load because two operators are difficult to load the film thereinto. 
     SUMMARY OF THE INVENTION 
     The present invention has been made in view of the above circumstances, and therefore an object of the invention is to provide a film loader for an image forming apparatus which makes it possible to readily load a film without damaging the film surface. 
     To achieve the above object, according to one aspect of this invention, there is provided a film loading method of an image forming apparatus, the method including: loading an endless film which was stored in a container box, using at least two support members, to a film frame of the image forming apparatus, wherein the film is supported by the support members in a different form with respect to a condition of the film when loaded and fitted to the film frame, wherein the support members are initially stored in the container box and serve as a packaging member for use in transporting and storing the film, wherein the support members are attached to respective portions of the film frame and guide the film to be loaded and fitted onto the film frame, wherein the film frame comprises holding rollers, and wherein the support members are attached to the respective portions of the film frame, coaxially with the holding rollers. 
     The different form may include a free form of the film being supported by the support members. 
     The different form may include an untensioned form of the film being supported by the support members. 
     The different form may include a loosened form of the film being supported by the support members. 
     The different form may include a flexible form of the film being supported by the support members. 
     The different form may include a loosely slackened form of the film being supported by the support members. 
     The different form may include a relaxed form of the film being supported by the support members. 
     According to another aspect of this invention, there is a film loading method of an image forming apparatus, the method including: preparing a film package that may include a container box in which at least two support members and an endless film are stored; taking out the film and the support members from the container box; attaching the support members to a film frame of the image forming apparatus; and loading the film on the film frame by moving the endless film from the support members onto the film frame, wherein, when preparing the film package, the support members serve as a packaging member for use in transporting and storing the film, wherein, when attaching the support members, the film is supported by the support members in a different form with respect to a condition of the film when loaded and fitted to the film frame of the image forming apparatus, wherein the at least two support members are attached to respective portions of the film frame and guide the film to be loaded and fitted onto the film frame, wherein the film frame may include holding rollers, and wherein the support members are attached to the respective portions of the film frame, coaxially with the holding rollers. 
     The different form may include a free form of the film being supported by the support members. 
     The different form may include an untensioned form of the film being supported by the support members. 
     The different form may include a loosened form of the film being supported by the support members. 
     The different form may include a flexible form of the film being supported by the support members. 
     The different form may include a loosely slackened form of the film being supported by the support members. 
     The different form may include a relaxed form of the film being supported by the support members. 
     According to another aspect of this invention, there is provided an image forming apparatus having a film frame for holding an endless film, and adapting to a film package including the film stored in a container box, including: the film frame includes attaching portions on which at least two support members, which support the film in a different form with respect to a condition of the film when loaded and fitted to the film frame, and which serve as a packaging member for use in transporting and storing the film, are attached, wherein the film frame may include holding rollers, and wherein the support members are attached to the attaching portions, coaxially with the holding rollers. 
     The different form may include a free form of the film being supported by the support members. 
     The different form may include an untensioned form of the film being supported by the support members. 
     The different form may include a loosened form of the film being supported by the support members. 
     The different form may include a flexible form of the film being supported by the support members. 
     The different form may include a loosely slackened form of the film being supported by the support members. 
     The different form may include a relaxed form of the film being supported by the support members. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       These and other objects and advantages of this invention will become more fully apparent from the following detailed description taken with the accompanying drawings in which: 
         FIG. 1  is a schematic view of a film loader with a photosensitive film loaded-according to the present invention; 
         FIG. 2  is a cross-sectional view of an attaching portion between a guide plate and a film plate according to the embodiment of this invention; 
         FIG. 3  is a schematic view of the film loader with the photosensitive film packaged according to another embodiment of the invention; 
         FIG. 4  is a schematic view of a film loader according to another embodiment of the invention; 
         FIG. 5  is a cross-sectional view of an attaching portion between the guide plate and the film plate according to this invention; 
         FIG. 6  is a cross-sectional view of an attaching portion between the guide plate and the film plate according to this invention; 
         FIG. 7  is a schematic view of a film loader according to another embodiment of the invention; 
         FIG. 8  is a cross-sectional view of an attaching portion between the guide plate and the film plate according to this invention; 
         FIG. 9  is a schematic view of a film loader according to another embodiment of the invention; 
         FIG. 10  is a cross-sectional view of an attaching portion between the guide plate and the film plate according to this invention. 
         FIG. 11  is a schematic view of an image forming apparatus to which the invention is applied; and 
         FIG. 12  is a schematic view of a conventional film loader with a photosensitive film loaded. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Now, a description will be given in more detail of preferred embodiments of the invention with reference to the accompanying drawings. 
     In the following description, a photosensitive film is employed, but the invention is not limited to thereto, and the invention may be applied to an intermediate transfer body, a transfer film, a carrier film and a fixing film besides the photosensitive film. 
     First Embodiment 
       FIG. 1  is a schematic view of a film loader for an image forming apparatus according to an embodiment of the invention. In  FIG. 1 , reference numeral  1  denotes a photosensitive film,  2   a  and  2   b  are pipes,  3   a  and  3   b  are adaptors,  4  is a guide member,  5  is a film frame, and  6   a  and  6   b  are holding rollers. 
     In loading the photosensitive film  1 , the film frame  5  is drawn horizontally from a main body of the apparatus not shown, the adaptors  3   a ,  3   b  and the guide member  4  are attached to the film frame  5  as shown in  FIG. 1 , and thereafter the pipes  2   a  and  2   b  around which the photosensitive film  1  is put are fitted to the adaptors  3   a  and  3   b , thereby supporting the photosensitive film  1 . The guide member  4  is tapered such that when an operator loads the film loader with the photosensitive film  1 , a slack occurring in the center of the photosensitive film  1  is eliminated along the taper of the guide member  4 . Also, because the photosensitive film  1  is supported by the pipes  2   a  and  2   b , the photosensitive film  1  can be prevented from dropping down. Accordingly, the photosensitive film  1  can be readily loaded into the film loader without damaging the surface of the photosensitive film  1 . In this case, the pipes  2   a  and  2   b  must be securely fitted to the adaptors  3   a  and  3   b , and the adaptors  3   a  and  3   b  must be securely fitted to the film frame  5 , respectively, as shown in  FIG. 2 . 
     In  FIG. 2 , reference numeral  2  denotes a pipe, reference numeral  3  denotes an adaptor, reference numeral  5  denotes a film frame, reference numeral  6  denotes a support roller, and reference numeral  7  denotes a flange. The flange  7  is so designed as to rotatably fit the support roller  6  to the film frame  5 . The adaptor  3  and the flange  7  are screwed such that they can be securely fixed to each other so as to prevent the adaptor  3  from dropping down. 
     A leading end portion of the adaptor  3  is tapered so that the pipe  2  can be readily inserted into the adaptor  3 . The dimensional relation between an inner diameter D 1  of the pipe  2  and an outer diameter D 2  of the adaptor  3  is placed in clearance fit, and because the outer diameter D 2  of the adaptor  3  ensures a length sufficient to fit the pipe  2  substantially horizontally, the pipe  2  can be surely fitted into the adaptor  3 . 
     The pipes  2   a  and  2   b  in  FIG. 1  are package members used for transport and storage of the photosensitive film as shown in  FIG. 3 . The pipes  2   a  and  2   b  as the package members are made of, for example, paper, resin or metal such as aluminum. Paper is superior from the viewpoints of low costs, lightweight and disposal. Also, resin is superior from the viewpoints of lightweight and high strength, and metal such as aluminum is superior from the viewpoint of high strength. Among those materials, paper pipes are most preferable to this invention. 
     Referring to  FIG. 3 , reference  1  denotes a photosensitive film,  2   a  and  2  are pipes,  8  is a container box, and  9   a  and  9   b  are pipe fixing members. The photosensitive film  1  is supported by the pipes  2   a  and  2   b , and then fixed on the pipe fixing members  9   a  and  9   b  in such a manner that the surfaces of the photosensitive film  1  are completely out of contact with the interior of the container box  8 . 
     In taking out the photosensitive film  1  from the container box  8 , an operator holds end portions  10   a  and  10   b  of the pipes  2   a  and  2   b , and then takes out the photosensitive film  1  and the pipes  2   a  and  2   b  together. This makes it unnecessary that the operator touches the surface of the photosensitive film  1  with his hand. As a result, the operator can take out the photosensitive film  1  from the container box  8  without damaging the surface of the photosensitive film  1 . 
     Referring to  FIG. 11 , the overall constitution of the above-mentioned image forming apparatus with the photosensitive film loaded will be described below. 
     A printing unit  18   a  includes a photosensitive film  19   a , an electrifier  20   a , an exposing unit  21   a , a developing unit  22   a , a transfer unit  23   a , and a cleaner  24   a . Printing units  18   b  to  18   d  are identical in construction with the printing unit  18   a.    
     The printing units  18   a  to  18   d  make the printing of different colors on a sheet  25 , for example, the printing unit  18   a  for yellow, the printing unit  18   b  for magenta, the printing unit  18   c  for cyan, and the printing unit  18   d  for black. 
     The printing operation of the printing unit  18   a  will be described below. The photosensitive film  19   a  starts to rotate on the basis of a printing operation start signal from a controller not shown, rotates at a rate corresponding to a print speed, and continues to rotate until the printing operation is completed. Upon starting to rotate the photosensitive film  19   a , a high voltage is applied to the electrifier  20   a  so that the surface of the photosensitive film  19   a  is evenly electrified with positive charges. 
     The character data or graphic data converted into dot images is sent from the controller not shown to the image forming apparatus with an on/off signal of the exposing unit  21   a , thereby forming an irradiated portion and a non-irradiated portion by the laser beam on the surface of the photosensitive film  19   a  by the exposing unit  21   a . A portion where charges disappear on the photosensitive film  19   a  comes to a position opposed to the developing unit  22   a  by irradiation of the laser beam from the exposing unit  21   a , the toner electrified with positive charges is absorbed by static electricity to form a toner image on the photosensitive film  19   a.    
     The sheet  25  is conveyed in synchronism with a timing when the print data formed on the photosensitive film  19   a  reaches a transfer position. The toner image formed on the photosensitive film  16   a  is sucked onto the sheet  25  due to an action of the transfer unit  23   a  that attaches charges of reverse polarity to the toner image onto the back side of the sheet  25 . The photosensitive film  19   a  that has passed through the transfer position is cleaned by the cleaner  24   a , and a residual toner on the photosensitive film  19   a  is absorbed by a suction blower not shown, and recovered into a recovery unit not shown, to prepare for the next printing operation. 
     The sheet  25  having passed through the printing unit  18   a  is subjected to the same printing operation in the printing units  18   b ,  18   c  and  18   d , and conveyed to the fixing unit  26 . The toner image on the sheet  25  that has reached the fixing unit  26  is molten and fixed on the sheet  25 . 
     The photosensitive films  19   a ,  19   b ,  19   c  and  19   d  are deteriorated by repeating the printing operation and therefore must be exchanged periodically. 
     Thus, using the film loader of the invention, the photosensitive film is easily loaded without detaching the film frame from the main body of the image forming apparatus and without damaging the surface of the photosensitive film by the operator. As a result, it is unnecessary to make an operation of removing the film frame every time the photosensitive film is exchanged, and it is possible to avoid damaging the surface of the photosensitive film before starting the printing operation to make the photosensitive film unusable. 
     Second Embodiment 
       FIG. 4  is a schematic view showing another embodiment of the invention. 
     In  FIG. 4 , in loading the photosensitive film  1 , the film frame  5  is drawn horizontally from the main body of the apparatus, the photosensitive film  1  is put around the pipes  2   a  and  2   b , and the pipes  2   a  and  2   b  are fitted on the film frame  5 , thereby supporting the photosensitive film  1 . As a result, the operator can correct a slack in the central portion of the photosensitive film  1  by his hand to load the photosensitive film  1  without damaging the surface of the photosensitive film  1 . 
     The pipes  2   a  and  2   b  are fitted on the film frame  5 , for example, with the construction shown in  FIG. 5 . A leading end portion of the flange  11  disposed on the film frame  5  is tapered so as to readily insert the pipe  2 . Also, the dimensional relation between the inner diameter D 1  of the pipe  2  and the outer diameter D 3  of the flange  11  is placed in tight fit/close fit, thereby making it possible to firmly fit the pipe  2  to the flange. 
     Alternatively, the construction shown in  FIG. 5  may be replaced by a construction of  FIG. 6 . In  FIG. 6 , reference numeral  2  denotes a pipe,  5  is a film frame,  6  is a support roller,  12  is a flange, and  13  is a fixing screw. 
     The flange  12  has a leading end portion tapered as in the case shown in  FIG. 5  so that the pipe  2  can be readily inserted into the flange  12 . Also, the dimensional relation between the inner diameter D 1  of the pipe  2  and the outer diameter D 4  of the flange  14  is placed in clearance fit, thereby making it possible to firmly fit the pipe  2  to the flange with the screw  13  after the pipe  2  has been inserted into the flange  12 . 
     Third Embodiment 
     Still another embodiment of this invention will be described below. 
     The constitution of this embodiment is fundamentally the same as shown in  FIGS. 4 to 6 , but has a feature that a packaging member for use in transporting or storing the film is directly employed as the pipe  2  that is the guide member as shown in  FIG. 3 . As in the case of  FIG. 4 , the operator corrects a slack in the central portion of the photosensitive film  1  by his hand to load the photosensitive film  1  without damaging the surface of the photosensitive film  1 . 
     Fourth Embodiment 
       FIG. 7  is a schematic view showing the structure of a film loader in an image forming apparatus according to still another embodiment of this invention. 
     In  FIG. 7 , reference numeral  1  denotes a photosensitive film,  5  is a film frame,  6   a  and  6   b  are support rollers, and  14  is a guide plate. 
     This embodiment shows an example where the work of attaching or detaching the photosensitive film with respect to the film frame after the photosensitive film is removed from the packaging member (for example, a paper pipe) is conducted. 
     In loading the photosensitive film  1 , the film frame  5  is horizontally drawn out from the main body of the image forming apparatus not shown, the guide plate  14  is fitted onto the film frame  5  as shown in  FIG. 7 , and thereafter the photosensitive film  1  is loaded into the film frame  5  to support the photosensitive film  1 . As a result, the operator can correct a slack in the central portion of the photosensitive film  1  by his hand to load the photosensitive film  1  without damaging the surface of the photosensitive film  1 . In this situation, the guide plate  14  must be surely fitted to the film frame  5 . A cross-sectional view of the fitting portion is shown in  FIG. 8 . 
     In  FIG. 8 , reference numeral  5  denotes a photosensitive film,  6  is a support roller,  14  is a guide plate, and  15  is a fixing screw. The guide plate  14  is firmly fixed to the film frame  5  with the screw  15 . 
       FIG. 9  is a schematic view showing the structure of a film loader according to still another embodiment of this embodiment. The construction of the guide member is different from that in the above-mentioned embodiment shown in  FIGS. 7 and 8 . 
     In this example, in loading the photosensitive film  1 , the film frame  5  is horizontally drawn out from the main body of the apparatus not shown, and the guide  16  is then fitted onto the film frame  5  as shown in  FIG. 9 . The guide l 6  is tapered, and a slack in the central portion of the photosensitive film  1  is eliminated along the tapered portion of the guide when the operator loads the photosensitive film  1  by his hand, thereby loading the photosensitive film  1  without damaging the surface of the photosensitive film  1 . In  FIG. 10 , reference numeral  17  denotes a fixing screw for fixing the guide  16  to the film frame  5 . 
     As was described above, according to this invention, there. can be provided the film loader for the image forming apparatus in which the film can be easily loaded without damaging the film surface. 
     The foregoing description of the preferred embodiments of the invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed, and modifications and variations are possible in light of the above teachings or may be acquired from practice of the invention. The embodiments were chosen and described in order to explain the principles of the invention and its practical application to enable one skilled in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the claims appended hereto, and their equivalents.