Patent Publication Number: US-6698959-B2

Title: Printer for printing paper roll having a position regulating device

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a printer for a printing paper roll, and more particularly to a printer in which the printing paper roll is easily loaded. 
     2. Description Related to the Prior Art 
     Among several kinds of printing paper or recording paper for a printer, there is a printing paper roll (hereafter paper roll), in which a long continuous printing paper is rolled around a roll core. The paper roll is loaded through a paper feed magazine of the printer, or directly into a paper roll chamber of the printer. The paper feed magazine or the paper roll chamber has a pair of frames, on which bearings, for example openings, are formed for supporting the shaft. When the paper roll is loaded, the shaft is fitted in a hole of the roll core to rotatably support the paper roll between the frames. Further, there is also another type of loading for the paper roll, in which paper holders are attached to both ends of the roll core such that the shaft protruding from the paper holders is inserted in the openings of the frames. 
     However, in the apparatus described above, the shaft has to be inserted in the bearings after the shaft is inserted in or the paper holder is attached to the roll core. Accordingly, it is hard to load the paper roll. Further, the radius of the paper roll may be reduced if it has been already used. Namely, the paper roll of a smaller radius is often loaded in the printer. Thereby, the chucking of the paper roll in the printer is troublesome. 
     SUMMARY OF THE INVENTION 
     A main object of the present invention is to provide a printer for a printing paper roll which can be easily loaded. 
     Another object of the present invention is to provide a printer for the printing paper roll in which the chucking of the printing paper roll in the printer is always carried out even if the radius of the printing paper roll is different. 
     In order to achieve the above and other objects, a printer for a printing paper roll of the present invention includes an openable loading lid, and a holder plate attached to the loading lid. An open angle between the loading lid and the holder plate is determined in accordance with a radius of the printing paper roll. A position of the printing paper roll relative to the loading lid is determined in accordance with the open angle. 
     A positioning device has first and second link mechanisms attached to the loading lid and the holder plate. The first and second link mechanisms include first and second positioning plates to contact to a periphery of the printing paper roll. After the printing paper roll is put on the loading lid, the loading lid is closed. Thereby the loading lid relatively moves to the holder plate, and the open angle becomes smaller. When the periphery of the printing paper roll contacts to the first and second positioning plates and the holder plate, the open angle decreases no more. Then, the loading lid and the holder plate move together with the certain open angle while the printing paper roll is held between them. The loading lid and the holder plate are rotatable, and preferably provided on a same shaft. 
     When the loading lid is set at a closed position, a detector generates a detection signals. Beside on the detection signal, a roll supporting device is driven. The roll supporting device slides a first or second support shaft to chuck and rotatably support the printing paper roll at a predetermined position. 
     According to the invention, the chucking of the printing paper roll is carried out when the loading lid is closed after putting the printing paper roll on it. Further, the loading lid is perfectly closed, a shaft hole of the printing paper roll is at a predetermined position, independent of changing of the radius of the printing paper roll. Therefore, the printing paper rolls having different radiuses can be surely chucked. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The above objects and advantages of the present invention will become easily understood by one of ordinary skill in the art when the following detailed description would be read in connection with the accompanying drawings: 
     FIG. 1 is a schematic diagram illustrating a thermosensitive color printer of the present invention; 
     FIG. 2 is a perspective view when a paper roll is loaded in the thermosensitive color printer; 
     FIG. 3 is a perspective view illustrating a structure of a paper feeding section; 
     FIG. 4 is a side view illustrating a structure of a paper roll holding mechanism; 
     FIG. 5 is a side view of the paper roll holding mechanism illustrating a situation when the paper roll is put on a loading lid; 
     FIG. 6 is a side view of the paper roll holding mechanism illustrating a situation when the paper roll which is not used is put on the loading lid; 
     FIG. 7 is a side view of the paper roll illustrating a situation when the paper roll which has been already used is put on the loading lid. 
    
    
     PREFERRED EMBODIMENTS OF THE INVENTION 
     In FIG. 1, the thermosensitive color printer  2  is constructed of a paper feeding section  3 , a printing section  4 , a fixing section  5 , a cutting section  6  and a controller  7 . In the thermosensitive color printer  2 , a thermosensitive color printing paper  8  is used. The printing section  4  is constructed of a first feed roller pair  11 , a thermal head  12 , a platen roller  13 , a second feed roller pair  14  and a paper sensor  15 , and they are disposed one by one in a feed direction A. The thermal head  12  is attached to a shift mechanism  16 . The shift mechanism  16  shifts the thermal head  12  into a printing position when printing is carried out, and into a retracted position when printing is not carried out. In the printing position, the thermal head  12  contact to the thermosensitive color printing paper  8  with an adequately pressure, and in the retracted position, the thermal head  12  is pulled up not so as to contact with the thermosensitive color printing paper  8 . Further, the platen roller  13  is confronted to the thermal head  12  to support the thermosensitive color printing paper  8  from a rear side thereof. The numerous  17  shows a head driver. 
     The second feed roller pair  14  consists of a capstan roller  20  and a nip roller  21 . The paper sensor  15  detects an end of the thermosensitive color printing paper  8 , and sends a detection signal to the controller  7 . The controller  7  controls a driver  23  to drive the pulse motor  22 . When a pulse motor  22  causes to rotate the capstan roller  20  in a clockwise direction, the thermosensitive color printing paper  8  is fed in the feed direction A, and thereby, printing on each coloring layer of the thermosensitive color printing paper  8  is carried out with the thermal head  12 . Further, when the pulse motor  22  causes the capstan roller  20  to rotate in a counterclockwise direction, the thermosensitive color printing paper  8  is fed in a feed back direction B, and prepare for printing on the next thermosensitive coloring layers. 
     The number of drive pulses is counted by a pulse counter  24  in order to control the pulse motor  22 . Based on the drive pulses, the controller  7  determines positions for starting printing, feeding back the color printing paper and cutting. The pulse counter  24  counts up the number of the drive pulse when the pulse motor  22  causes the capstan roller  20  in the clockwise direction, and the pulse counter  24  counts down the number of the drive pulse when the pulse motor  22  causes the capstan roller  20  in the counterclockwise direction. 
     A fixing device  27 , a cutter  28  and a paper feed roller pair  29  are disposed downstream from the thermal head  12  one by one along the feed direction A. The fixing device  27  is constituted of a yellow fixing lamp  31 , a mazenta fixing lamp  32 , a reflector  33  and a fixing drive section  34 . The yellow fixing lamp  31  emits a violet light whose wave length is at the peak about 420 nm. The mazenta fixing lamp  32  emits a ultraviolet ray whose wave length is at the peak about 365 nm. When yellow images are printed, the controller  7  causes the yellow fixing lamp  31  through the fixing drive section  34  to emit the violet light. Further, when mazenta images are printed, the controller  7  causes the mazenta fixing lamp  32  through the fixing drive section  34  to emits the ultraviolet ray. While cyan images are printed, the mazenta fixing lamp  32  continues to emit the ultraviolet ray in order to bleach unprinted areas slightly colored yellow. 
     The controller  7  controls the cutter  28  through the driver  35  to cut the thermosensitive color printing paper  8  into a sheet. The paper feed roller pair  29  feeds the sheets through an outlet. 
     As shown in FIG. 2, a printing or recording paper roll (hereafter paper roll)  40  is used in the thermosensitive color printer  2 . In the paper roll  40 , the thermosensitive color printing paper  8  is rolled around a roll core  41  made of plastic or paper. When the paper roll  40  is sold, an edge thereof is fixed with an adhesive tape. Further, it is packed in a package, such as a bag and a box having a moisture proof characteristic and a light-shielding property. In order to begin to use the paper roll  40 , it is withdrawn from the package and loaded in the paper feeding section  3 . 
     The thermosensitive color printer  2  includes a printer body  2   a . In the printer body  2   a , printing mechanisms, for example, the paper feeding section  3 , the printing section  4 , the fixing section  5  and the cutting section  6 , are contained. A front face of the printer body  2   a  is provided with a loading lid  42 . In order to load the paper roll  40 , a grip  44  is caught with a hand and pulled forwards to open the loading lid  42 . Then, the paper roll  40  is put on the loading lid  42 . Inside of the loading lid  42 , a holder plate  43  is rotatably attached and constructs a part of the paper feeding section  3 , in combination with the loading lid  42 . Then, the paper roll  40  is supported by the loading lid  42  and the holder plate  43 . When the loading lid  42  is closed, the paper roll  40  is loaded in the paper roll feed section  3 . 
     As shown in FIG. 3, in the paper feed section  3 , paper roll support shafts, a slide mechanism  46  and the like are disposed. The paper roll shaft is deposited at a predetermined position and constituted of a drive shaft  48  and a driven shaft  49  which are arranged in a line. The drive shaft  48  is caused by a drive motor  47  to rotate, and the driven shaft  49  is slid toward the drive shaft  48  by the slide mechanism. The drive shaft  48  and the driven shaft  49  are plastic molded articles and, and their ends have a cone-shaped form. Further, flanges  50 ,  51  are formed on the drive shaft  48  and the driven shaft  49  in order that a side edge of the paper roll  40  does not have a volute form. 
     When the loading lid  42  is perfectly closed, a lid open/close sensor  52  generates detection signals. Corresponding to the detection signals, the controller  7  controls the slide mechanism  46  to slide the driven shaft  49  towards the paper roll  40  at a predetermined position. The driven shaft  49  enters into a hole  41   a  of the roll core  41  of the paper roll  40 . Thereby, the flange  51  presses the paper roll  40  towards the drive shaft  48  such that the drive shaft  48  may be entered into the hole  41   a  of the roll core  41 . Thus the paper roll  40  is supported by the paper roll shaft between flanges  50  and  51 . When a position detection sensor  53  detects that the paper roll shaft supports the paper roll  40 , the controller  7  causes the slide mechanism  46  to stop. The numeral  54  shows a driver. 
     As shown in FIG. 4, a roll holding mechanism  58  is attached inside the loading lid  42 . The roll holding mechanism  58  is constituted of the holder plate  43 , a first position regulate section  59  and a second position regulate section  60 . The holder plate  43  is coaxially attached with the loading lid  42 , and urged to a stopper  62  by a spring  61  (see FIG.  5 ). The holder plate  43  is rotated by a shift mechanism  55  (see FIG. 6) in a counterclockwise direction against bias of a spring, after the drive shaft  48  and the driven shaft  49  enter in the hole  41   a  of the roll core  41 . 
     The first position regulate section  59  is constituted of a positioning plate  63  and a link mechanism (pantograph mechanism)  64  and a connection link  68 . The second position regulate section  60  is constituted of a positioning plate  66  and a link mechanism (pantograph mechanism)  67 . Positions of the first and second positioning plates  63 ,  66  are determined corresponding to an angle between the loading lid  42  and the holder plate  43 . 
     The link mechanism  64  is constructed of rotary links  70 ,  71 . An end of the rotary link  70  is connected to the positioning plate  63 . Another end of the rotary link  70  contacts to the end of the connection link  68 , and they are connected with a pin  76  which is slidably fitted in a groove  42   a  formed in the loading lid  42 . An end of the rotary link  71  is connected to the loading lid  42 , and another end thereof is slidably fitted in a groove  63   a  of the positioning plate  63  with a pin. The rotary links  70 ,  71  cross, and they are connected to each other with a pin  72 . 
     The link mechanism  67  is constructed of rotary links  74 ,  75 . An end of the rotary link  74  is connected to the positioning plate  66 . Another end of the rotary link  74  contacts to the end of the connection link  68 , and a pin  77  provided through them is connected to the holder plate  43 . An end of the rotary link  75  is connected to the loading lid  42 , and another end thereof is slidably fitted in a groove  66   a  of the positioning plate  66  with a pin. The rotary links  74 ,  75  cross, and they are connected to each other with a pin  78 . 
     According to the roll holding mechanism  58 , when the loading lid  42  is set at a closed position, a position of the center of the roll core  41  is deposited at or near to the predetermined position independent of largeness of the radius of the paper roll  40 . As shown in FIG. 6, when the paper roll  40  of the large radius that is not used is loaded, the open angle between the loading lid  42  and the holder plate  43  is large. Thereby, the center of the paper roll  40  is at the position shown in x=L 1 , y=H 1  (where the length- and widthwise directions are determined to x- and y-directions). Further, as shown in FIG. 7, when the paper roll  40  of the small radius is loaded, the open angle is small. Accordingly, the first and second position regulate sections  59 ,  60  protrude more than those in FIG. 5, and the center of the paper roll  40  is at the position in x=L 2  (≈L 1 ), y=H 2  (≈H 1 ). 
     The effect of the present invention will be explained now. When the paper roll  40  is loaded in the thermosensitive color printer  2 , a locking mechanism (not shown) of the loading lid  42  is released, and thereafter, as shown in FIG. 2, the loading lid  42  is opened to a predetermined position. Thereby, as the shift mechanism  55  is released such that the holder plate  43  may be free, the holder plate  43  is moved by the bias of the spring  61  to contact to the stopper  62 . While the loading lid  42  is opened, the open angle between the loading lid  42  and the holder plate  43  becomes larger, and the pin  76  attached to one of the end of the connection link  68  slides downward in the groove  43   a . Namely, the link mechanism  64  opens and the positioning plate  63  is retracted towards the loading lid  42 . At the same time, the link mechanism  67  of the second position regulate section  60  opens, and the positioning plate  66  is retracted. When the paper roll  40  is put on the loading lid  42  in this situation, the paper roll  40  is supported by the positioning plates  63 ,  66 . 
     Then, the loading lid  42  is closed. As shown in FIG. 5, as the holder plate  43  contacts to the stopper  62  and is stopped, the loading lid  42  moves toward the holder plate  43 . Thereby the angle between the loading lid  42  and the holder plate  43  becomes smaller. Simultaneously, the link mechanism  67  closes and the positioning plate  66  moves forward. Further, as the link mechanism  64  is closed through the connection link  68 , the positioning plate  63  protrudes from the loading lid  42  to push the paper roll  40  toward the holder plate  43 . Then the paper roll  40  contacts to the positioning plate  63 , and the link mechanisms  64  and  67  are fixed. Thus, the paper roll  40  is held by the loading lid  42  and the positioning plates  63 ,  66 . When the loading lid  42  is closed furthermore, the holder plate  43  is rotated counterclockwise against the bias of the spring  61 . Thereby the loading lid  42  and the holder plate  43  are rotated together while the open angle between them is kept corresponding to the largeness of the radius of the paper roll  40 . 
     When the loading lid  42  is closed perfectly, the loading lid  42  is locked by the locking mechanism and kept in a closed position. The lid open/close sensor  52  outputs signals to the controller  7 . When receiving the signals, the controller  7  drives the slide mechanism  46  to move the driven shaft  49  towards the paper roll  40 , and the roll core  41  of the paper roll  40  is, regardless of the radius thereof, positioned at or near the predetermined position. Therefore, the driven shaft  49  can smoothly enter in the roll core  41 . Further, the flange  51  presses the paper roll  40  toward the drive shaft  48 , and the drive shaft  48  enters in the other end of the roll core  41 . Thus the paper roll  40  is supported between the flanges  50 ,  51  by the paper roll shaft. 
     When the paper roll  40  is supported by the drive shaft  48  and the driven shaft  49 , the holder plate  43  is rotated counterclockwise by the shift mechanism  55  to be apart from the paper roll  40 . Corresponding to the moving of the holder plate  43 , the open angular between the loading lid  42  and the holder plate  43  becomes larger, and the positioning plates  63 ,  66  becomes away from the paper roll  40 . When printing is carried out, the drive motor  47  causes to rotate the paper roll  40 . As the paper roll  40  is unwound, the thermosensitive color printing paper  8  is fed out of the paper feed section  3  to the printing section  4 , and printing is made. Thereafter, a part where the printing has been made is cut into a sheet, and the sheet is fed out from the thermosensitive color printer  2 . 
     In order to change the paper roll  40 , the loading lid  42  is opened. Thereby signals from the lid open/close sensor  52  are input in the controller  7 . The controller  7  drives the slide mechanism  46  to extract the driven shaft  49  from the roll core  41 . Then, the shift mechanism drives to release the holder plate  43 , and the holder plate  43  is rotated toward the loading lid  42  by the spring  61 . Thereby the roll core  41  is extracted from the drive shaft  48 , and then, the roll core  41  or the paper roll  40  in use is nipped by the positioning plate  63  and the holder plate  43 . The holder plate  43  is rotated by the spring  61  in accordance with the opening of the loading lid  42 , during which the holder plate  43  contacts to the stopper  62 . Thereafter, only the loading lid  42  rotates to the open situation illustrated in FIGS. 2 and 5. 
     The flange  50  had better be biased by a spring to be slidable to the drive shaft  48 . In this structure, when the driven shaft  49  is extracted from the roll core  41 , the flange  50  is moved by the spring such that the roll core  41  may be pressed out of the drive shaft  48 . Further, the loading lid  42  may be slidable. 
     The present invention is not applied only to the thermosesitive color printer in which the paper roll is used, but also may be applied to a ink jet printer in which a best quality paper roll is used, and a photo printer in which a photographic paper roll is used. 
     Various changes and modifications are possible in the present invention and may be understood to be within the present invention.