Patent Publication Number: US-6337970-B1

Title: Image forming apparatus having sheet processor

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to an image formation apparatus having a sheet processor, and more particularly, to an image formation apparatus having a sheet processor for stacking and sorting sheets ejected from the apparatus, the processor having a punching means for punching holes in sheets. 
     2. Description of the Related Art 
     In a conventional sheet sorter for processing sheets, approximately 20 trays for stacking sheets (hereinafter referred to as “bins”) are arranged in such a manner as to be mutually separated by a specified distance; sheets ejected from the image formation apparatus sequentially in a specific period of time are carried in order into specified bins by a carrying means. 
     Regarding a method for punching holes in sheets, which is employed in such a sheet sorter, a method for punching holes into a pile of sheets placed in the bins is known. This method, however, has some problems: while punching of holes is being performed, the subsequent sheet cannot be carried to the sheet processor, since punching of holes is performed on a pile of sheets. In addition, depending on punching capability, it is necessary to suspend the carrying of sheets from the image formation apparatus to the sheet processor every time holes are punched into a pile of sheets. As a result, these problems hinder the improvement of processing speed. 
     Accordingly, for example, a method for respectively punching holes in each of the sheets ejected from the apparatus sequentially in a specified period of time is known; furthermore, there is known a method in which punching is performed without an increase in sheet processing time, regardless of whether punching processing is performed, by disposing a punching means composed of a punch and a die on a sheet carrying path, and bringing a sheet carrying speed into synchrony with a punching speed so as to perform punching without stopping the sheet which is being carried. 
     In the conventional examples, when an action of punching is selected through the image formation apparatus, the action of punching is required to be input before the starting action for forming an image in the apparatus is input. Thus, when image formation is started without setting of punching, image formation by the apparatus must be suspended. 
     SUMMARY OF THE INVENTION 
     The present invention has been made to overcome these problems. It is an object of the present invention to provide an image formation apparatus having a sheet processor in which an action setting of a punching unit can be performed during a specified period of time, even after image formation starts. 
     According to an aspect of the present invention, there is provided an image formation apparatus having a main section and a sheet processor section, which includes; an image forming unit for forming an image on a sheet; an ejecting unit for ejecting the sheet on which the image is formed by the image forming unit, wherein the image forming unit and the ejecting unit are contained in the main section of the image formation apparatus; a punching unit for punching at least one hole in a sheet ejected from the main section of the image formation apparatus, the punching unit being disposed in the processor; and a punch action selection unit for selecting punch action. The image formation apparatus has a controlling unit for controlling the punch action selecting unit in such a manner that a punch action selection by the punching unit is permitted during a specified period of time after start of image formation signal is input. 
     The image formation apparatus having a sheet processor described above may also include a sheet detecting unit for detecting the arrival of a sheet at the sheet processor; a specified period of time taken after the starting of the image formation is input may coincide with the period of time taken for the first sheet upon which an image has been formed from the main section of the image formation apparatus to arrive at the sheet detecting unit. 
     Preferably, the sheet detecting unit described above is an entry sensor which is arranged upstream of the punching unit. 
     According to an another aspect of the present invention, there is provided an image formation apparatus which includes: an image forming unit for forming an image on a sheet; a carrying path for guiding the sheet on which the image is formed by the image forming unit; an ejecting unit for ejecting the sheet guided by the carrying path; a stacking unit for stacking the sheet ejected by the ejecting unit; a processing unit disposed in the carrying path for performing processing on the sheet guided by the carrying path; a selection signal input unit for inputting a selection signal for selecting a mode either for operating the processing unit or for not operating the same; a start signal input unit for inputting a start signal for starting an image formation; and a controlling unit for controlling the processing unit according to the mode selected by the input selection signal when the selection signal is input after the start signal is input. 
     Based on the arrangement above, when a punch action is selected by the punch action selection unit, the sheet upon which an image has been formed is ejected and carried from the main section of the image formation apparatus is punched by the punching unit. Even after input of the starting of the image forming action performed by the main section of the image formation apparatus, as long as it occurs during a specified period of time, a selection of a punch action by the punch action selection unit can be accepted. Thus, the setting of the punch action selection unit within the specified period of time permits a punch action by the punching unit to be performed, even if the action setting of the punch action selection unit is forgotten; and there is no need to pause the image formation apparatus halfway through a job, so that a satisfactory use environment of the apparatus can be obtained. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a cross-sectional front view of an image formation apparatus in which a sheet processor of the present invention is applied; 
     FIG. 2 is a block diagram according to an embodiment of control of the sheet processor of the present invention; 
     FIGS. 3 through 7 are flowcharts according to actions of the sheet processor of the present invention; and 
     FIG. 8 is a front view of an operation unit of the sheet processor of the present invention. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring now to the drawings, a description will be given of an embodiment of the present invention. FIG. 1 is a sectional view which shows an overall structure of an image formation apparatus including a read/feed device  101  for feeding and reading a document sheet, a main section of the image formation apparatus  102 , and a sheet sorter  103 . 
     In the system, the read/feed device  101  has an automatic document feeder  51  and an optical unit  52 : the feeder  51  feeds an original document paper P which is set on a document feeding tray  51   a  to a document read position formed of a platen glass  52   a , and carries it to an ejecting position after the image of the original document is read, while the optical unit  52  scans the document paper P to be read. The read image of the document is converted into electric signals by an image processor  52   b . 
     In addition, the image formation apparatus  102  has a plurality of record paper containers  53  and  54  for stacking record sheets S 1 , S 2  of different sizes and a plurality of record sheet feeders  55  and  56  for feeding the record sheets. The sheet fed from one of the record sheet containers  53  and  54  is carried to a pair of resist rollers  60  of the image formation apparatus  102  via a sheet carrying path  57 . 
     Numeral  61  denotes a laser scanner for scanning by a laser beam based on the image information read by the optical unit  52 , and numeral  62  denotes an image forming means (or unit) in which scanning performed on a photosensitive drum  62   a  by the laser scanner  61  permits formation of a toner image. The sheet on which an image is formed by the image forming means  62  after being carried by the resist rollers  60  in a specified timing is carried onto a carrying path  10  of the sheet sorter  103  by a carrying belt  63 , fix rollers  64 , and ejection rollers  65  as an ejecting means. 
     The sheet sorter  103  is composed of a bin unit  5  for sorting out sheets for stacking and holding; a sheet carrying unit  2  for carrying a sheet ejected from the image formation apparatus  102  to the sheet sorter  103 ; a punching unit  4  as a processing means for punching holes in the sheet which is being carried within the sheet carrying unit  2 ; a staple unit  6  for stapling a pile of sheets stacked in the bin unit  5 ; an operation unit  7  for inputting an action of the sheet sorter  103 , etc. 
     Next, a description will be given of a basic operation of the apparatus, referring to FIG. 2 which is a block diagram showing a structure of a controller shown in FIG. 1 employed in the embodiment. 
     A controller circuit unit  200 , which is a CPU circuit unit, includes a central processing unit  2002  (hereinafter referred to as “CPU”) for calculating by using a specified program, or controlling the processing unit as a whole; ROM for containing a program and specified data; RAM for containing data temporarily corresponding to signal processing; or an IC card, a floppy disk, etc.; and further includes, memory  2001  for writing/reading a program and data, and an I/O controller  2003  for transmitting and controlling an input/output signal. 
     Furthermore, a timer for counting time is included in the CPU  2002 , while a plurality of registers is included in the CPU  2002  and the I/O controller  2003  so as to use data signals for a temporary memory/read processing. These devices are respectively controlled by a control signal from the CPU circuit unit, which is a controller circuit unit  200 . 
     The controller circuit unit  200  operates a unit controller  201 , a bin unit controller  202 , a sheet carrying unit controller  203 , a punch unit controller  204 , a communication controller  205 , and a staple unit controller  206 , which are included in the controller  210  of the sheet processor, by setting of an action input from the main section of the image formation apparatus  102  or setting of an action input from the operation unit  7  by the communication controller  205 . Numeral  8  denotes a communication line, which connects the controller circuit unit  200  to the controller  210  of the sheet processor. Numeral  211  denotes a start key, which is a start signal input means for inputting a start signal for starting image formation performed by the image formation apparatus  102 . 
     In this arrangement, when a user places original documents in the document feeding tray  51   a  of the automatic document feeder  51  disposed in the read/feed device  101  and sets an action mode to designate start of copying by using an operation unit (not shown) of the image formation apparatus  102 , each of the documents P is fed one by one through the automatic document feeder  51  to be read by the optical unit  52  as a reader. 
     In the optical unit  52 , a CCD line sensor performs photoelectric conversion of the exposed document image so as to read it as electric signals. Then, different kinds of image processing are performed on the read image signal corresponding to a setting by a user through the operation unit of the image formation apparatus  102  so as to be converted into an optical signal used for photoreceptor exposure through the image processor  52   b . After this, through the process including electric charging, exposure, latent-image formation, printing, separation, and fixing, which is conventional in electrophotography, the image is recorded on the sheet. The sheet on which the image is formed is carried to the carrying path  10  of the sheet sorter  103  through the carrying belt  63  and the ejecting rollers  65  as an ejecting means. In the sheet sorter  103 , the controller circuit unit  200  allows the sheet carrying unit controller  203  to operate corresponding to an action set by the communication controller  205 . 
     The communication controller  205  receives data such as size data of the sheet ejected from the image formation apparatus  102 , processing speed data of the image formation apparatus  102 , data for designating an action of stacking sheets of the sheet sorter  103 , a job start signal of the sheet sorter  103 , an initialization start signal, a staple start signal, a reversed signal of bin shift direction, a sheet ejection signal, a final sheet ejection signal, etc., of the sheet sorter  103 . 
     In addition, the communication controller  205  transmits data such as the number of bins to be used, a sheet arrival signal for indicating an arrival of a sheet from the image formation apparatus  102 , a standby signal for indicating a standby state of the sheet sorter  103 , a busy signal for indicating a working state of the sheet sorter  103 , a staple-ON signal for indicating a stapling state of the sheet sorter  103 , and different kinds of alarm signals for indicating malfunctions, etc. The communication controller  205  performs transmission and reception of such controlling data mainly by a communication control IC (not shown). 
     The sheet ejected from the image formation apparatus  102  is moved to the sheet carrying unit  2 . The controller circuit unit  200  allows the sheet carrying unit controller  203  to operate according to the sheet stacking action designating data which is input by the communication controller  205  to activate a carrying flapper  11  for changing the sheet carrying course. When the sheet is stacked in a stacking tray  30  in a bin unit, it is ejected into the stacking tray  30  of the bin unit  5  through stacking tray ejection rollers  12 . Meanwhile, when the sheet is stacked in a stack bin  31  as a stacking means in the bin unit  5 , it is carried to the punching unit  4  through a carrying roller  13 . 
     When an entry sensor  16  (a sheet detecting means) detects a top edge of the sheet being carried within the sheet carrying unit  2 , the operation unit  7  prohibits acceptance of input for setting a punch action by an operation of a punch setting button  71  (a selection switch). 
     When a punch action is selected by the operation unit  7 , the controller  200  as a controlling means allows the punching unit controller  204  to operate, and allows a punch  28  (a punching means) to operate corresponding to the timing in which a sheet detecting sensor  26  detects the sheet so as to punch holes in the sheet. The punching unit controller  204  detects a punch sensor  27  to stop the punch  28 . Then, residue cut out by punching, which is a waste punched-out disk, falls and is contained in a punch-residue container  24 , which is a box for containing the residue produced by punching. The punch-residue container  24  has a punch-residue sensor which detects that the punch-residue container  24  is filled with punch-residue. The punched sheet is ejected from stack bin ejection rollers  15  through a carrying roller  14  to a stack bin  31 , which is a stacking means. 
     After all the sheets for the job are stacked, when a staple start signal which is input from the operation unit  7  or the communication controller  205  permits selection of a staple action, the controller  200  allows the staple unit controller  206  and the bin unit controller  202  to operate respectively so as to allow the staple unit  6  to sequentially staple piles of the sheets stacked in the stack bins  31 . 
     In the operation unit  7  shown in FIG. 8, numeral  71  denotes a punch setting button, which is a selection signal input means for inputting a selection signal to select a mode either for operating or for not operating the punching means  28  as a processing means; numeral  72  denotes a punch-residue full-capacity display; numeral  73  denotes an operation button for starting or stopping stapling the piles of the sheets; numeral  76  denotes a staple sorting display: numeral  77  denotes a display for indicating positions to be stapled for a manual stapling; numeral  79  denotes an operation button for stapling; and numerals  81  and  82  denote the respective buttons for moving the stack bin  31  up and down. 
     Referring now to the flowcharts shown in FIGS. 3 to  7 , a description will be given of the details in the operation of the embodiment above. 
     The CPU circuit unit  200  starts a program after the power is turned on (S- 1 ); the CPU  2002 , in turn, waits for an input of an initialization start signal in the communication controller  205  (S- 2 ); then, when the start signal for initialization is input, the CPU  2002  performs initialization by controlling the communication controller  205 , the bin unit controller  202 , the sheet carrying unit controller  203 , the punching unit controller  204 , the staple unit controller  206 , and the operation unit controller  201 , respectively. 
     After initialization, the CPU  2002  sets a punch-input permission flag for giving permission to input a punch action in the operation unit  7  (S- 31 ); then, the CPU  2002  allows the operation unit controller  201  to operate to accept input of a bin action and staple action (S- 32 ), and allows the bin unit controller  202  and the staple unit controller  206  to operate to perform an input action which is designated by a user through the operation unit  7  (S- 33 ); when the job start signal is input in the communication controller  205 , the CPU  2002  performs a processing of job starting procedure S- 11  (S- 34 ); and when the job start signal is not input in step S- 34 , the CPU  2002  repeats the processing of step S- 32 . 
     In step S- 20 , the CPU  2002  allows the operation unit controller  201  to operate to accept an input of a punch action selection, when it determines whether the punch action flag for permitting an input of the punch action in the operation unit  7  is set; in step S- 21 , when the punch action is selected by the operation unit  7 , the CPU  2002  sets the punch action flag to perform the procedure of step S- 20  (S- 22 ), so that the sheets are punched in the job processing step S- 12 . In contrast, in step S- 21 , when the punch action is not selected by the operation unit  7 , the CPU  2002  clears the punch action flag to perform the procedure of step S- 20  (S- 23 ), so that the sheets are not allowed to be punched in the Job processing step S- 12 . The CPU  2002  constantly performs the procedure of step S- 20 . 
     When the Job start signal is input by the communication controller  205 , the CPU  2002  controls the bin unit controller  202 , the sheet carrying unit controller  203 , the punching unit controller  204 , and the staple unit controller  206  to perform a job start processing action for preparing for the job processing (S- 11 ). When a sheet ejection signal is input by the communication controller  205 , the CPU  2002  controls the bin unit controller  202  and the sheet carrying unit controller  203  so as to perform a job processing action based on stacking designation data, a bin-shift-direction reverse signal, size data of the sheets to be ejected, and processing speed data of the image formation apparatus, which are input by the communication controller  205 . 
     In FIG. 7, the CPU  2002  clears the punch input permission flag to cancel an input of a punch action selection from the operation unit  7  (S- 42 ) when it determines whether the top edge of the sheet is detected by the entry sensor  16  (S- 41 ); and the CPU  2002  controls the punch unit controller  204  to punch holes in the sheet which is being carried (S- 12 ) when it determines whether the punch action flag is set. 
     In other words, when the top edge of the sheet being carried within the sheet carrying unit is detected by the entry sensor  16  which is a sheet detecting means, the operation unit  7  prohibits the acceptance of an input for setting a punch action made by operating the punch setting button  71 . Regarding the punch setting button  71 , an action setting of the button  71  which is a punch action selection means is permitted during a specified period of time taken after the start key  211  of the operation unit (not shown) in the image formation apparatus  102  shown in FIG. 1 is operated and the job start signal is input from the main section of the image formation apparatus  102  by the communication controller  205 . 
     The specified period of time mentioned above is the time between an input for starting of an image forming action by the start key  211  and an arrival of the first sheet in the job, which is an image formation on a pile of the sheets, at the entry sensor  16 . 
     This arrangement permits the punching of holes in the sheets carried to the sheet sorter  103 , as long as the punch setting button  71  is operated within a specified period of time, even after image formation is started by operating the start key  211 ; thus, even if the setting of punching is forgotten, both image formation and sheet processing can be continued without putting the apparatus on hold, so that the use environment of the apparatus can be enhanced. 
     The CPU  2002  controls the bin unit controller  202 , the sheet carrying unit controller  203 , and the punch unit controller  204  so as to perform a job processing ending action (S- 13 ), when the final sheet ejection signal, etc., is input by the communication controller  205  to eject all the sheets. Furthermore, the CPU  2002  controls the staple unit controller  206  and the bin unit controller  202  so as to perform a stapling procedure on the stacked sheets (S- 13 ), when a staple start signal is input by the communication controller  205 , or when a staple action is input for setting by the operation unit  7 . 
     The CPU  2002  performs step S- 23  when it determines whether the sheets to be sorted and stacked are removed through a sheet detecting sensor  32  disposed in the stack bins  31 . In step S- 14 , when the CPU  2002  determines whether the sheets to be sorted and stacked are left in the bins  31 , it performs step S- 15 ; and then it performs step S- 11  for a series of actions when another job start signal for the next job is input by the communication controller  205 . The CPU  2002  repeats steps S- 13 , S- 14 , and S- 15  until a signal for starting the next job is received or the sheets are removed from the stack bin  31 . 
     In the embodiment described above, the start switch disposed in the image formation apparatus is a start signal input means, while the selection switch disposed in the processor is a selection signal input means. However, when a printer connected to a personal computer is used as an image formation apparatus, the computer may be employed as a start signal input means or a selection signal input means. 
     In addition, the processing means described in the embodiment may be a folding means for folding sheets, or a stamping means for stamping sheets, as an alternative to the punching means. 
     While the present invention has been described with respect to what is presently considered to be the preferred embodiments, it is to be understood that the invention is not limited to the disclosed embodiments. The present invention is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.