Abstract:
A method and an apparatus of paper separation are provided which permit a secure and reliable auto-loading operation of paper separation with a less complex mechanism of the apparatus. The paper separation apparatus has a paper separation body for separating a paper from a transfer body, a paper feeding supporter for holding the paper firmly and supporting the feed of the paper, and a link mechanism for moving the paper separation body toward a circumferential surface of the transfer body. The arrangement separates the paper from the transfer body in an auto-loading step and moves at least a portion of the paper feeding supporter to hold the separated paper firmly, so that the movement of the paper separation body is co-acted in synchronism with the movement of the paper feeding supporter.

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates in general to a printer and more particularly to a paper separation (or release) apparatus and paper separation method which are applicable to an image or picture formation apparatus as a printer for printing and image formation on a continuous, sequence paper. 
     FIG. 8 shows a general structure of a high-speed printer for a continuous, sequence paper. In a case that a continuous, sequence paper is not set to this high speed printer, or in a case that discontinuous papers (in a bundle) are set by some unknown reasons in place of the continuous, sequence paper and therefore reset is to be made, a continuous, sequence paper P of a paper buffer portion  200  is set in an auto-load portion  201  and then a start switch for the auto-load portion (not shown) is put on, so that the paper P is automatically fed to a transfer portion  202 , a fixture portion  203  and a stacker portion  204 . By this operation, the continuous, sequence paper P is on a stand-by state for a printing operation. The serial, consecutive paper-loading operation is called as an auto-load operation. 
     Japanese Patent Publications (unexamined) No. 9-90775 (1997) and No. 3-13444 (1991) show structures in which a continuous, sequence paper P is fed from a transfer drum and guided to a fixture portion  203  and a stacker portion  204  through some guides. An example of such a guide construction and a pinch roller construction is shown in FIG. 9, by which a paper loading operation is conducted in the transfer portion  202  at the time of an auto-load operation. The paper P which is fed from an auto-load table portion (that is, a table provided in the auto-load portion  201  shown in FIG. 8) is fed by a lower pin  102  of transfer portion and then fed upward as it is closely contacted with the transfer drum  103 . The paper P closely contacted with the transfer drum  103  is abutted against a guide  104 , which has a minor gap (approximately, 0.8 mm) relative to the drum  103  and then released. Then, the paper P is pulled by the pinch roller  105  so that apertures of the paper P are engaged with upper pins  106  of the tractor of the transfer portion. 
     The pinch roller  105  is, as shown in FIG. 10, generally stands by at an upper portion of the feeding direction of the paper P. When the paper P is fed to advance by the auto-load operation, the pinch roller is moved upward relative to the feeding direction of the paper P and, as shown In FIG. 11, serves to hold the paper P to feed it toward the tractor upper pin  106 . 
     However, as a continuous, sequence paper, which is usually referred as a continuous form P, has recently been used extensively and, when such a thin paper is used and fed into the transfer portion  202 , it is likely that the thin paper is freely delivered through a space between the transfer drum  103  and the guide member  104  without a required contact by these members  103  and  104  with the result that there is a problem of unavailability of the auto-loading. 
     With respect to separation of a paper, an attempt was made to provide a paper releasing nail for releasing a paper as disclosed in Japanese Utility Model Publication (unexamined) No. 5-20072 (1993). However, this technique does not permit the paper to be released from a circumferential surface of the transfer drum and therefore is not a good measure for solving the problems described above. Further, Japanese Patent Publication (unexamined) No. 2-238480 (1990) discloses a structure in which a paper releasing nail is provided to a paper supporting drum which supports a paper for feeding, but this attempt does not release a paper from a circumferential surface of the transfer drum and, therefore, the aforementioned problems have not been solved yet. In view of the structural feature of the transfer drum, the paper releasing nail as described above sometimes provides damages on the surface of the drum at the time of releasing operation of the paper from the drum surface by the use of the nail and, therefore, results in damages in the circumferential surface of the drum and generation of undesirable noises in printing and image or picture. Thus, use of the paper releasing nail as described above results in deterioration of printing and image (picture) properties. In the structure disclosed in the above-described Publication No. 2-238480, the paper is released from the circumferential surface of the drum during the paper feeding operation by means of the releasing nail, and this is not a paper releasing from a circumferential surface of the transfer drum and, therefore, this method is applicable. 
     On the other hand, provided that there should be a suggestive structure of a paper-separation nail for separating a paper from the transfer drum, it must be that this structure will have the structure as follows. Namely, it must be constructed such that the paper release nail is contacted with the circumferential surface of the transfer drum  103  at the time of auto-loading mode only and, further, a paper releasing operation must be finished by the nail before the pinch roller is driven for the above-mentioned pulling operation. Apart from the operational structure of the pinch roller  105 , if it is required to provide a controlling device for controlling the operation of the paper separation nail, additional mechanism must be provided for a synchronous operation with the pinch roller  105 . This, however, will provide a new serious problem of complexity in mechanical structure. 
     SUMMARY OF THE INVENTION 
     In view of the foregoing, an object of the present invention is to provide an improvement in a method and apparatus of paper separation which permit a secure and reliable auto-loading operation of paper separation with less complex mechanism of the apparatus. 
     According to the present invention, there is provided a paper separation apparatus which comprises a paper separation body for separating a paper from a transfer body; a paper feeding supporter device for holding the paper firmly and supporting the feed of the paper; and a link mechanism for moving the paper separation body toward a circumferential surface of the transfer body so as to separate the paper from the transfer body in an auto-loading step and moving at least a portion of the paper feeding supporter device to thereby hold firmly the separated paper, so that the movement of the paper separation body is co-acted in synchronism with the movement of the paper feeding supporter device. 
     In the structure described above, when the continuous, sequence paper is fed to the transfer body at the time of the auto-loading operation, the paper separation body is moved toward the circumferential surface of the transfer body by means of the link mechanism, at the moment of which a movement of the paper feeding supporter can be started if desired, the paper is separated from the transfer body. Then, by the link mechanism, at least a part of the paper feeding supporter is further moved to thereby hold the separated paper by the paper feeding supporter and, after that, the paper feeding operation is enhanced by the paper feeding supporter. 
     As described above, the operation of the paper separation body and the operation of the paper feeding supporter are co-acted with each other in synchronism and this synchronized operation permits a reliable paper separation and auto-loading operation. 
     The paper feeding supporter device preferably includes at least a pinch roller but is not limited to this structure, and any other structure can be used so long as it can hold the continuous, sequence paper and feed the same to a lower portion of the structure. According to the present invention, it is defined in the claim that, by the link mechanism described above, at least a part of the paper feeding supporter device is moved. This means that if at least one of the rollers (preferably, a pinch roller) is moved by the link mechanism as defined in the claim, the remaining other roller can serve to hold the paper. 
     The paper separation body preferably has a paper separation nail which can release or separate the paper, and it is further preferred that the paper separation nail can be rotated in the paper feeding direction. By the rotational mechanism of the paper separation nail, no damage or injure is produced on the circumferential surface of the transfer body by the link mechanism when the paper separation nail is contacted with the circumferential surface of the transfer body. 
     In an embodiment of the paper separation apparatus, the structure comprises a paper feeding supporter device for holding a paper and supporting the paper to be fed; a link mechanism for moving at least a part of the paper feeding supporter device to thereby hold the paper in an auto-loading operation; and a paper separation body for separating the paper from the transfer body so that the link mechanism is operated in synchronism with the paper feeding supporter device to thereby move the paper separation body toward a circumferential surface of the transfer body and separate the paper from the transfer body immediately before the paper feeding supporter device holds the paper. 
     In this structure, the link mechanism which serves to move the paper feeding supporter device is provided with a function for moving synchronously the paper feeding supporter device with the paper separation body. These movements are operated by a single link mechanism and, therefore, an operational structure for the paper feeding supporter device is separately and independently provided from an operational structure for the paper separation body. In this structure, additional synchronism mechanism for synchronously operating these movements will not required. 
     In a further feature of the invention, there is provided a method which has the steps of separating a paper which has been fed by moving a paper separation body toward a circumferential surface of a transfer body, moving at least a part of a paper feeding supporter device in synchronism with the movement of the paper separation body, and holding the separated paper to thereby support a paper feeding operation. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a diagrammatic view of an interior of a high-speed printer incorporating the structure of an embodiment of the invention. 
     FIG. 2 is a diagram of a paper separation apparatus in a transfer portion designated at  202  according to the present invention showing a state of a home-position of the apparatus. 
     FIG. 3 is a plan view of the paper separation apparatus according to the present invention. 
     FIGS. 4A and 4B are explanatory diagrams showing the structure of a paper separation nail which is designated by reference numeral  1 . 
     FIG. 5 is an explanatory diagram showing a state that the paper separation apparatus of the invention is conducting a paper separation operation at position B. 
     FIG. 6 is an explanatory diagram showing a state that the paper separation apparatus of the invention is conducting a paper-feed supporting operation at position C. 
     FIG. 7 is a timing diagram showing an operation and detection of parts of the printer in accordance with an auto-loading operation. 
     FIG. 8 a diagram showing a structure of the printer for a high-speed printer using a continuous, sequence paper. 
     FIG. 9 is an explanatory view showing a general operational mode in the transfer portion  202  at an auto-loading operation. 
     FIG. 10 is a diagram which shows a stand-by position of a pinch roller which is shown by reference numeral  105 . 
     FIG. 11 is a diagram which shows a state of the pinch roller at the auto-loading operation. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Preferred embodiments of the invention will be described with reference to the figures of the accompanying drawings. 
     In FIGS. 1 through 6 showing a paper separation apparatus according to an embodiment of the present invention, the paper separation apparatus is adaptable to a high-speed printer connected with a main frame and the like for the apparatus, and a paper separation is conducted for a continuous, sequence paper P at the time of the auto-loading operation by the printer. 
     In FIG. 1 showing an operation of paper loading in a transfer (picture transfer) at an auto-loading operation, a continuous, sequence paper P (in other words, a continuous form) is set to an auto-loading portion  201  (auto-loading table portion  101 ) and, when an auto-load starting switch (not shown) is switched on, the paper P is fed to the transfer portion  202 . In other words, the paper is fed by a tractor lower pin  102  of a transfer portion and then transferred upward while it is closely contacted with a transfer drum  103 . The paper P which is contacted with the transfer drum  103  is then separated or released from the transfer drum  103  by a paper separation nail  1  which will be described presently and then held between a pinch roller  2  and a driving roller  3  of rubber which is located below the pinch roller  2  and further to a downstream portion of the paper. After the holes or apertures of the continuous paper P are snugly adapted to a tractor upper pin  106  of the transfer portion, the paper P is fed further to a fixture portion  203  and a stacker portion  204  which are located downstream portion of the paper feed so that the paper P is placed in a stand-by posture for a printing operation. 
     In FIG. 1, the transfer portion  202  is composed mainly of the transfer drum  103  and its peripheral, optical picture (image) transfer elements, such as a precharge portion  111  which is set around the transfer drum  103  for charging the drum  103 , an optical portion  112  which is composed of an LED array for optically irradiating or exposing an image (or a picture) toward the transfer drum  103  in accordance with image data transmitted from a host, a developer unit  113  which serves to affix particles such as a toner onto a latent image formed at the optical portion  112  to thereby form a printing image on the transfer drum  103 , a cleaning brush  114 , which may have a cleaning blade, for exclude the toner remaining on the transfer drum  103  after completion of a printing step on the paper P, a discharge LED  115  for the transfer drum  103 , and a cleaning fleece  116 . 
     In FIG. 2 showing the paper separation apparatus according to the present invention which is set in the transfer portion  202  located adjacent to a circumferential surface of the transfer drum  103 , the paper separation apparatus has a paper separation nail  1  which represents specifically the paper separation body, a pinch roller  2  and a lower driving roller  3  which in combination represent and serve as the paper feeding supporter device, and a link mechanism  4 . The basic frame  110  of the transfer portion is provided with, as described in detail presently, the aforementioned link mechanism  4  which has a pivotal axis  41   a  of a first link  41 , a pivotal axis  43   b  of a third link  43  and a bearing  11  for pivotally support a rotational axis  10  of a fifth link  45 . 
     As shown in FIGS. 2 and 3, the paper separation nail  1  is provided, on an extended end portion of the fifth link  45 , to the rotational axis  10  which is disposed perpendicularly relative to the fifth link  45  of the link mechanism  4 . 
     The rotational axis  10  is pivotally supported to the basic frame  110  of the transfer portion by the bearing  11 , as shown in FIG.  3 . Since the extended end of the rotational axis  10  is fixed to the fifth link  45 , the rotational axis  10  is rotated at an axis of the bearing  11  by the rotation of the fifth link  45  and, as shown in FIG. 5, a tip end of the paper separation nail  1  can be contacted with a circumferential surface of the transfer drum  103 . 
     On the other hand, the paper separation nail  1  is fitted to an axis  13  of a metal member  12  through a spring  14 , as shown in FIGS. 4A and 4B. Thus, in a normal state the paper separation nail  1  is held in a state as shown in FIG. 4A by a resilient force of a spring  14  but, at the same time, is rotatable in the direction shown by an arrow in the illustration at the axis  13 . This rotatable structure is useful for prevention of generation of damages on the circumferential surface of the transfer drum  103  by the rotation of the paper separation nail  1  when the nail  1  contacts the circumferential surface of the transfer drum  103 . 
     With respect to the pinch roller  2 , a plurality of pinch rollers  2  are rotatably provided to a shaft  20  in an axially alignment posture as shown in FIG. 3, in which the shaft  20  is disposed perpendicular to the third link  43 , at the other end of the third link  43  of the link mechanism  4  which will be described presently. Accordingly, since the third link  43  is rotated toward a transfer drum  103 , the pinch rollers  2  are moved to the driving roller  3  of a rubber roller below the pinch rollers  2  and, finally, forced against the driving roller  3 . 
     The link mechanism  4 , which is shown in FIGS. 2 and 3, has a pinch roller compression motor  40  (DC motor) which is fixed to the base frame  110  of the transfer portion, a first link  41 , a second link  42 , a third link  43 , a fourth link  44 , and a fifth link  45 . The first link  41  is eccentrically engaged with a spindle  40   a  of the DC motor  40  and rotatable about a point  41   a  extended from the base frame  110 . The second link  42  is rotatable about a pivotal point  42   a  at the other end of the first link  41 . The third link  43  is rotatable about a pivotal point  43   a  at the other end of the second link  42  and pivotally supported at a pivotal point  43   b  of the base frame  110  so that the third link  43  is rotatable about the pivotal point  43   b  in the direction of the transfer drum  103 . The fourth link  44  is rotatable about the pivotal point  43   a  at the other side of the second link  42 , and the fifth link  45  is rotatable about a pivotal point  45   a  at the other end of the fourth link  44 . 
     In the structure described above, the spindle  40   a  of the pinch roller compression motor  40  and the first link  41  are engaged with each other by the structure that an eccentric rotational body  40   b  is eccentrically fitted to the spindle  40   a  and the eccentric rotational body  40   b  is longitudinally movably disposed in an oblong engagement hole  41   b  of the first link  41 . Since the first link  41  is rotatable about a point which is extended from the base frame  110 , the first to fifth links  41 - 45  are all moved by a rotation of the spindle  40   a  as shown in FIGS. 5 and 6. This movement will be described presently. 
     In the structure described above, the spindle  40   a  is provided at its end with a circular plate or a disc  46  with a notch  46   a  for detecting a position. The pinch roller compression motor  40  has, on its circumferential portion, three position sensors  47   a - 47   c  at predetermined three positions as shown in FIG.  2 . The position sensors  47   a - 47   c  have projections  48   a,    48   b  which extend along the opposed sides of the disc  46  as illustrated in FIG. 3, and one of the projections  48   a,    48   b  is provided with a light emitting portion (not shown) and the other is provided with a light receiving portion or receptor portion (not shown), and the notch  46   a  of the disc  46  is moved between them and when the light receiving portion receives an emitted light from the light emitting portion, it is determined that the disc  46  is rotated to the position of the sensors  47   a - 47   c,  and thus the rotational state of the link mechanism  4  is detected. The sensor  47   a  detects that the link mechanism  4  is located in the home position (that is, position A) as shown in FIG.  2 . The sensor  47   b  detects that the link mechanism  4  is located in the position B of FIG. 5, and the sensor  47   c  detects the link mechanism in the position C of FIG.  6 . 
     An operational mode of the apparatus having the structure as described above will be described with reference to FIGS. 2,  5  and  6 . 
     The position A shown in FIG. 2 represents a normal, unoperational state of auto-loading (that is, home position). In this stage, the notch  46   a  of the disc  46  is detected by the sensor  47   a.  The pinch rollers  2  stand by at the position spaced from the driving roller  3 . The paper separation nail  1  is spaced from the transfer drum  103  with a small gap therebetween. 
     Then the auto-loading start switch is pushed down to be switched on to execute an auto-loading operation, the pinch roller compression motor  40  is driven, so that the first link  41  is rotated at a center of the point  41   a  and its end is moved toward the transfer drum  103 . Then, as shown in FIG. 5, the second link  42  is moved in the direction shown by an arrow (that is, toward the transfer drum  103 ), and the third link  43  starts to rotate in the direction of an arrow (that is, in the direction that the other end of the third link moves toward the paper delivery). At this moment, the pinch roller  2  is not contacted with the driving roller  3  or the paper P and positioned in a spaced relation. The fourth link  44  is also rotated in the same direction as the third link  43  at a center of the pivotal point  43   a.  The fifth link  45  is rotated in the direction of an arrow (in the direction that the pivotal point  45   a  moves toward the paper delivery direction) at a center of the bearing  11 . By the rotation of the fifth link  45 , the paper separation nail  1  is contacted with a circumferential surface of the transfer drum  103 . In the state of position B as shown in FIG. 5, the notch portion  46   a  of the disc  46  is detected by the sensor  47   b.  Further, in this state, when the continuous paper P is fed toward the transfer drum  103  by a paper delivery motor (not shown), the end of the paper is contacted with the paper separation nail  1  and spaced from the transfer drum  103  and then fed toward the pinch roller  2 . 
     When the pinch roller compression motor  40  is continuously driven, the first link  41  is further rotated at a center of the point  41   a  and, as shown in FIG. 6, the second link  42 , the third link  43 , the fourth link  44  and the fifth link  45  are continued to move in the direction of an arrow. In this instance, the continuous paper P is continuously fed by the paper delivery motor, and fed through between the pinch roller  2  and the driving roller  3 , at which point the paper is stopped and held at a moment. Then, the third link  43  is rotated in the direction of paper delivery at a center of the pivotal point  43   b,  and the continuous paper P is then held by the combination of the pinch roller  2  and the driving roller  3 , so that the driving roller aids the feeding of the continuous paper P and serves to feed it toward the upper tractor pin  106 . At this moment, since the fifth link  45  is rotated further in the direction of an arrow, the paper separation nail  1  is rotated in the arrowed direction on FIG.  4 B and the end of the nail  1  is kept contacted with a circumferential surface of the transfer drum  103  by means of a spring  14 . In such a position as the position C in FIG. 6, detection of the notch portion  46   a  of the disc  46  is carried out by the sensor  47   a.  Then the feeding operation of the paper P is started again by the paper delivery motor. 
     By the operation as described above, the continuous paper P is separated from the circumferential surface of the transfer drum  103  in the auto-loading operation, and the continuous paper P is then automatically fed to the fixture portion  203  and the stacker portion  204 . Thus, the continuous paper is positioned in the stand-by status and awaits the forthcoming printing operation. After the auto-loading operation, the pinch roller compression motor  40  is rotated in the reversal direction and returned to the home position shown in FIG.  2 . 
     FIG. 7 is a timing diagram of operations of an auto-loading table motor (not shown), an auto-loading table set sensor (not shown), a cleaning brush  114 , a paper feed motor (not shown), a pinch roller compression motor  40  and sensors  47   a - 47   c.  The detection of a set position, a separation position and a down position by the sensors  47   a - 47   c  corresponds to the aforementioned positions A, B, and C. In this diagram, start of the paper feeding represents start of the auto-load operation and the stop of the paper feeding represents a stand-by position for forthcoming printing operation after the auto-loading operation is finished. 
     As illustrated in FIG. 7, in the timing of a home position A, a paper absorption is made and the auto-loading table motor is driven. When the auto-loading table sensor detects that a paper P is placed on the auto-loading table, the paper absorption operation is stopped and also the operation of the auto-loading table motor is stopped. At this moment, an operation of paper feeding is started and the cleaning brush of the transfer drum  103  starts its operation and, at the same time, the pinch roller compression motor  40  is rotated so that the step of the home position A shifts to the position B. 
     After the sensor  47  detects the position B, the paper feed motor is driven to feed paper toward the transfer drum  103 . Here, the paper P which is contacted with the transfer drum  103  is contacted with the paper separation nail  1  which has been contacted with the circumferential surface of the transfer drum  103 , and then separated from the transfer drum  103  and advanced to the pinch roller  2 . In this step, the pinch roller compression motor  40  is rotated again so that position B is shifted into position C. 
     After the sensor  47   c  detects the state of position C, the operation of the paper feeding motor is stopped. In this state, the paper P is already fed through between the pinch roller  2  and the driving roller  3 , and the pinch roller  2  is lowered from the position above the paper P to hold the paper P with the co-action of the driving roller  3 . Then the paper feeding motor is driven to proceed the paper feeding and, at this moment, the both pinch roller  2  and the driving roller  3  serve to aid the paper feeding operation as described above. 
     When the holes or apertures of the paper P are successfully engaged with the tractor upper pins  106 , a further paper feed aiding operation is no more required and, therefore, the pinch roller compression motor  40  is reversely rotated so that the position is shifted back or returned from position C to position A. During this operation, the paper feed motor is continued to feed the paper P, and the paper feed operation is interrupted to finish the auto-loading operation and, at this moment, the paper P is placed to stand-by for the following printing operation. 
     In the embodiment of the present invention described above, the paper separation nail  1  and the pinch roller  2  are co-acted (or interlocked) to move and, after the paper separation is made by the paper separation nail  1 , the separated continuous paper P is held between the pinch roller  2  and the driving roller  3  so that the driving roller  3  aids to feed the paper and, therefore, a reliable operation of the auto-loading can be made. In other words, the link mechanism  4  which serves to move the pinch roller  2  is provided with another function of moving at the same time the paper separation nail  1 , and these operations are conducted by the same and single mechanism, that is, the link mechanism  1 . Thus, it is no required to provide different devices, one for operating the pinch roller  2  and the other for operating the paper separation nail  1 , and therefore it is not necessary to provide additional devices for synchronizing operation of the two devices  1 ,  2 . 
     Although the present invention has been described with reference to the preferred embodiments thereof, it should be appreciated that many modifications and alterations can be made within the spirit of the invention. 
     According to the paper separation apparatus in a feature of the invention, both the paper separation and the paper-feed aiding operation are conducted in an interlocking manner so that the paper separation and the continuous paper feeding are continuously operated. Thus, the present invention can provide a remarkable effect that the auto-loading operation can be carried out reliably and accurately. 
     In the second feature of the invention, the link mechanism which serves to move the paper feeding supporter device is provided with additional function of simultaneously moving the paper separation body, and these two operations are proceeded by a single link mechanism. Therefore, it is not required to provide different devices which proceeds each of the two operations separately and independently and, moreover, it is not required to provide any additional mechanism or device which serves to perform synchronously the two operations. 
     Further, in the paper separation method of the present invention, the paper separation step and the continuous-paper feeding step are proceeded in a coactive or interlocking manner, without synchronism between the two operations, to complete an auto-loading operation.