JP2013107747A - Post-processing method and post-processing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To maintain carrying performance while preventing a superposition state of a paper bundle from being disturbed during a carrying operation.SOLUTION: A post-processing apparatus includes a folding unit which forms a fold line on paper, a superposition unit which forms a plurality of sheets of paper into the paper bundle by stacking the plurality of sheets of paper each having the fold line formed thereon, a carrying unit which carries the paper bundle, and a control unit which controls a carrying speed of the carrying unit. In the case of carrying the paper having an image formed thereon and applying post-processing to the paper, the post-processing apparatus controls the carrying speed when carrying the paper bundle according to the state of the paper bundle and predetermined conditions.

Description

  The present invention relates to a post-processing method and a post-processing apparatus that convey a sheet on which an image is formed in a state in which a crease is formed.

  By connecting various post-processing apparatuses in the image forming apparatus, various bookbinding processes can be performed, and the apparatus can be used as a printing apparatus.

  In such a post-processing device of the printing apparatus, the paper is folded in the middle of the paper, and the folded paper is further overlapped to form a paper bundle, and staple processing is performed on the fold portion of the paper bundle. Saddle-stitched book-like shape is possible. Further, it is also possible to output a sheet bundle in a state of being folded in a folded state without performing a stapling process.

  In such a post-processing apparatus, it is necessary to convey a sheet bundle in a folded state or a folded sheet bundle without delay in accordance with the productivity of the image forming apparatus. In recent years, the productivity of image forming apparatuses has improved, so even inside the post-processing apparatus. There is a need to transport such a bundle of sheets as fast as possible.

  However, the stacking state of the sheet bundle is likely to be disturbed or dropped due to the wind pressure received during conveyance.

  Note that the following patent document proposes such a disturbance during conveyance of a sheet bundle.

JP 2005-324932 A JP 2005-271087 A

  In the above Patent Document 1, the sheet bundle is pressed by the friction member when the sheet bundle is conveyed. Furthermore, the shape and pressing strength of the friction member are changed according to the size (volume) of the sheet bundle so that the disturbance of the sheet bundle does not occur. However, according to this method, a pressing member, a pressing mechanism, a pressing pressure control unit, and the like are required, which causes a new problem that the cost of the post-processing apparatus increases.

  In addition, pressing a part of the paper with a member is not desirable in order to keep the state of the output product in good condition. Similarly, although the sheet bundle is not disturbed by lowering the conveyance speed, it is not desirable from the viewpoint of keeping the productivity of the image forming apparatus constant.

  On the other hand, in Patent Document 2 described above, when the sheet bundle is cut, the speed at which the sheet bundle is rotated is changed according to the volume of the sheet bundle to prevent the deviation at the time of rotating the sheet bundle. However, this patent document 2 is about rotation, and cannot be applied to paper disturbance (shift or drop) during conveyance.

  The present invention has been made in view of such a problem, and provides a post-processing method and a post-processing apparatus capable of maintaining conveyance performance while preventing disturbance of a stacking state of sheet bundles during conveyance. The purpose is to do.

  That is, the present invention for solving the above-described problems is as follows.

  (1) In the first invention, a folding unit that forms a crease on a sheet, a stacking unit that stacks a plurality of the sheets on which the folds are formed to form a sheet bundle, and a transport unit that transports the sheet bundle, A control unit that controls the conveyance speed of the conveyance unit, and conveys the image-formed sheet and performs post-processing on the sheet according to the state of the sheet bundle and a predetermined condition. The conveyance speed at the time of conveying the sheet bundle is controlled.

  (2) The second invention is characterized in that, in the above (1), the state of the sheet bundle includes presence / absence of unification of the sheet bundle, an amount of paper, and a paper size.

  (3) In a third aspect of the invention, in the above (2), when the sheet bundle is integrated, the sheet bundle weight determined by the number of sheets constituting the sheet bundle, the amount of paper and the sheet size is used. The conveyance speed is controlled, and when the sheet bundle is not integrated, the conveyance speed is controlled by the weight of one sheet determined by the amount of paper and the sheet size constituting the sheet bundle. And

  (4) In a fourth invention according to the above (2) to (3), the state of the sheet bundle includes a surface state relating to slipperiness of the sheets constituting the sheet bundle, and the surface state is taken into account. And controlling the conveying speed.

  In the above (2) to (3), the state of the sheet bundle includes an environmental condition of humidity or temperature regarding the slipperiness of the sheets constituting the sheet bundle, and the conveyance is performed in consideration of the environmental condition. It is characterized by controlling the speed.

  (5) In a fifth aspect of the present invention, in the above (1) to (4), the transport unit includes a mounting unit that supports a lower angle portion of the fold of the sheet from below, and the stack of sheets is mounted. It conveys in the state mounted in the part.

  (6) In a sixth aspect based on the above (5), the transport unit is in a state where the sheet bundle is placed on the placement unit, and the sheet bundle is transported without being suppressed from above. Features.

  (7) In a seventh aspect of the present invention, in the above (5) to (6), in the transport unit, the placement unit includes a collar-shaped collar portion that supports an inferior portion of the fold of the sheet from below. It is characterized by being.

  (8) In an eighth invention according to the above (1) to (7), the transport unit is capable of transporting in a parallel direction and an orthogonal direction of the folds of the sheet bundle. It further includes a relationship between the direction of the fold and the conveyance direction.

  (9) In a ninth aspect of the present invention, in the above (1) to (7), the control of the transport speed includes at least one of control regarding acceleration and speed control during transport at a constant speed. Features.

  According to the present invention, the following effects can be obtained.

  In the present invention, when conveying a sheet bundle generated by superimposing a plurality of sheets having creases formed thereon, the conveyance speed for conveying the sheet bundle according to the state of the sheet bundle and predetermined conditions. To control. Here, the state of the sheet bundle includes whether or not the sheet bundle is integrated, the amount of paper, the paper size, and the slipperiness. When the sheet bundle is integrated by staples or the like, the conveyance speed is controlled by the sheet bundle weight determined by the number of sheets, the weight and the paper size constituting the sheet bundle, and the sheet bundle is integrated. If not, the conveyance speed is controlled by the weight of one sheet determined by the amount of paper and the paper size constituting the sheet bundle. By controlling the conveyance speed in this way, it is possible to maintain the conveyance performance while preventing disturbance of the stacking state of the sheet bundle during conveyance.

  In addition, by controlling the conveyance speed according to the state of the paper as described above, a placing portion such as a hook shape that supports the subordinate angle portion of the paper fold from below without suppressing the paper bundle from above. In addition, even when the sheet bundle is transported in a state where it is placed on the placing portion, it is possible to maintain the transport performance while preventing disturbance of the overlapping state of the sheet bundle during the transportation.

  Further, when the sheet bundle can be conveyed in the parallel direction and the orthogonal direction, the conveyance speed is controlled by further considering the relationship between the direction of the crease and the conveyance direction as the state of the sheet bundle, Regardless of the direction of conveyance with respect to the fold line, it is possible to maintain the conveyance performance while preventing disturbance of the stacking state of the sheet bundle during conveyance.

  Also, the conveyance speed control includes at least one of acceleration control and speed control at the time of conveyance at a constant speed, thereby preventing disturbance of the stacking state of the sheet bundle during conveyance. It becomes possible to maintain performance.

It is a block diagram which shows the structure of the post-processing apparatus of embodiment of this invention. It is a block diagram which shows the structure of the post-processing apparatus of embodiment of this invention. It is a block diagram which shows the structure of the principal part of the post-processing apparatus of embodiment of this invention. It is a flowchart which shows operation | movement of the post-processing apparatus of embodiment of this invention. It is a flowchart which shows operation | movement of the post-processing apparatus of embodiment of this invention. It is explanatory drawing which shows the control state of the post-processing apparatus of embodiment of this invention. It is a flowchart which shows operation | movement of the post-processing apparatus of embodiment of this invention. It is explanatory drawing which shows the control state of the post-processing apparatus of embodiment of this invention.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention (hereinafter referred to as embodiments) will be described in detail with reference to the drawings.

[Configuration of image forming system]
With reference to FIGS. 1 to 3, the configuration of an image forming system including a post-processing apparatus according to the present embodiment will be described.

  As shown in FIGS. 1 and 2, the image forming system includes an image forming apparatus 100, a reverse conveying apparatus 200, a post-processing apparatus 300, and a post-processing apparatus 400.

  The image forming apparatus 100 includes a control unit 101 that controls each unit in the image forming apparatus 100 and controls the entire system as a post-processing device, a communication unit 102 that communicates with other connected devices, and an operator. The operation unit display 103 for notifying the control unit 101 of an operation input signal corresponding to the operation input by the control unit and displaying the status of the image forming apparatus 100; storing the control program and various setting data; Storage unit 104, sheet feeding unit 105 that feeds the stored paper, transport unit 110 that feeds the fed and image-formed paper at a predetermined speed, and scans the document to generate image data A document reading unit 120 that performs image formation, an image data storage unit 130 that stores image data and various types of data for image formation, An image processing unit 140 for performing image processing, an image forming unit 150 for performing image formation (printing) on the basis of the image formation instruction and the image data is configured to include a. Note that the paper on which the image is formed by the image forming apparatus 100 is carried out toward the reverse conveyance apparatus 200 at the subsequent stage.

  The reverse conveying apparatus 200 is connected to the subsequent stage of the image forming apparatus 100 and to the previous stage of the post-processing apparatus 300, and includes a control unit 201 that controls each part in the reverse conveying apparatus 200, the image forming apparatus 100, and the post-processing apparatus. A communication unit 202 for communicating with 300, a storage unit 204 for storing a control program and various setting data and used as a work area for the control program, a transport unit 210 for transporting paper at a predetermined speed, and an image forming apparatus The reversing unit 220 reverses the sheet from 100 and sends it to the subsequent stage, and the aligning unit 230 that aligns the reversed sheet.

  The post-processing apparatus 300 is connected to the subsequent stage of the reverse conveyance apparatus 200, and includes a control unit 301 that controls each unit in the post-processing apparatus 300 and a communication unit 302 that communicates with the image forming apparatus 100 and the reverse conveyance apparatus 200. A storage unit 304 that stores a control program and various setting data and is used as a work area of the control program, a discharge path selection unit 305 that selects a discharge path for discharging a post-processed sheet bundle, and a predetermined sheet. Folded by the sheet transport unit 310 that transports at a speed, the folding unit 320 that folds the sheet in half or in three, the stacking unit 330 that stacks the sheets for post-processing to form a sheet bundle, and the folding unit 320 A saddle stitching unit 340 for performing saddle stitching as a post-processing on the sheet bundle superposed by the superimposing unit 330, and a sheet bundle conveying unit 350 for conveying the sheet bundle in a state of a sheet bundle. A cutting unit 360 for cutting the fore edge portion of the sheet bundle, and includes a.

  The post-processing apparatus 400 is connected to the subsequent stage of the post-processing apparatus 300, and includes a control unit 401 that controls each unit in the post-processing apparatus 400 and a communication unit 402 that communicates with the image forming apparatus 100 and the post-processing apparatus 300. A storage unit 404 that stores a control program and various setting data and is used as a work area of the control program, a discharge path selection unit 405 that selects a discharge path for discharging a post-processed sheet bundle, and a predetermined sheet. A transport unit 410 that transports at a speed, a staple unit 420 that staples a bundle of sheets, a main tray discharge unit 440 that discharges sheets with the main tray as a discharge destination, and a sub-tray discharge unit 450 that discharges sheets with the sub-tray as a discharge destination And comprising.

  The connection of the image forming apparatus 100, the reverse conveying apparatus 200, the post-processing apparatus 300, and the post-processing apparatus 400 in FIGS. 1 and 2 is an example of an image forming system, and is not limited to such a connection. Absent. Further, in the mechanical configuration of FIG. 2 and FIG. 3, the principle configuration of the main part is mainly shown, and known paper conveyance and alignment are shown in a omitted state.

  In FIG. 2, when the post-processing device 400 performs post-processing on the paper transported in the X direction from the image forming apparatus 100, the post-processing is performed while discharging the paper as it is, and is discharged.

  On the other hand, when post-processing is executed in the post-processing apparatus 300, the folding unit 320 shown in FIG. 2 pushes up the sheet with a folding knife from below and sandwiches the sheet and the folding knife with two rollers, thereby A crease with a ridge is formed and a middle fold is executed. Then, the folded sheet is overlapped by the overlapping unit 330 while being conveyed in the Y direction to form a sheet bundle. The saddle stitching unit 340 performs saddle stitching on the sheet bundle. Further, the sheet bundle is conveyed in the X direction by the sheet bundle conveying unit 350 and sent to the cutting unit 360.

  As described above, the sheet that has been conveyed in the X direction by the image formation is formed with a fold in the Y direction to form a sheet bundle, and the sheet bundle is conveyed in the Y direction parallel to the fold to perform saddle stitching. As a result, the execution efficiency of post-processing increases, and the productivity of the image forming system can be increased.

  Further, as shown in FIG. 3, the sheet bundle transport unit 350 includes a bowl-shaped placement unit 351 that supports a lower angle portion (angle less than 180 °) of the fold of the sheet bundle Pp from below, and includes the sheet bundle Pp. Is driven in the Y direction by the Y direction driving unit 352, and the Y direction driving unit 352 itself is driven in the X direction by the X direction driving unit 353. Therefore, the loading unit 351 can convey the sheet bundle Pp in both the Y direction parallel to the fold and the X direction perpendicular to the fold. As shown in FIG. 3, the sheet bundle conveying unit 350 conveys a portion of the folded angle of the sheet bundle Pp that is supported by a saddle-shaped placement unit 351 from below. Thus, no member for pressing the sheet bundle Pp from above is provided.

[Operation]
Hereinafter, the flowcharts of FIGS. 4 and 5 and the operation of this embodiment will be described.

  Here, the control of the post-processing apparatus 300 in the image forming system in the connected state shown in FIGS. 1 and 2 will be mainly described.

  When image formation is started, the control unit 301 of the post-processing apparatus 300 includes information related to image formation (image formation information: paper type, paper size, conveyance speed, etc.) and information related to the processing mode for post-processing ( Request post-processing mode information) to the control unit 101. In response to this, the control unit 101 notifies the control unit 301 of image formation information and post-processing mode information related to the post-processing apparatus 300 from the job information. The post-processing mode information includes information such as folding type, binding selection presence / absence, and cutting selection presence / absence.

  Upon receiving the image formation information and the post-processing mode information, the control unit 301 determines whether the folding type of the post-processing to be executed is “tri-fold” or “half-fold”. Here, as the post-processing apparatus 300, a case where the middle folding to the saddle stitching to the cutting or the middle folding to the cutting is performed is taken as a specific example.

  Then, the control unit 301 determines the sheet bundle conveyance speed in the post-processing apparatus 300 from the image formation information and the post-processing information (step S1 in FIG. 4).

  In the post-processing apparatus 300, the sheet transport unit 310 transports the sheet sent from the image forming apparatus 100 in the X direction in FIG. 2 in accordance with the sheet discharge interval of the image forming apparatus 100. Further, the sheet bundle conveyance unit 350 conveys the sheet bundle generated by being overlapped by the overlapping unit 330 toward the saddle stitching unit 340 and the cutting unit 360 at a predetermined sheet bundle conveyance speed in the Y direction and the X direction. (Step S2 in FIG. 4).

  As described in the prior art, the sheet bundle may be disturbed by the wind pressure received during the conveyance, so that the conveyance performance is prevented while preventing the stacking state of the sheet bundle from being disturbed. The control unit 301 determines the sheet bundle conveyance speed capable of maintaining the image quality with reference to image formation information and post-processing mode information.

[Speed determination (1)]
Hereinafter, the process for determining the sheet bundle conveyance speed will be described with reference to the flowchart of FIG.

  The control unit 301 refers to post-processing mode information to check whether or not the sheet bundle generated by folding is integrated by saddle stitching (step S101 in FIG. 5), and the sheet bundle is integrated by saddle stitching. 5 (YES in step S101 in FIG. 5), “weight = number of sheets contained in sheet bundle × sheet weight (unit area weight) × sheet area” is calculated (step S102 in FIG. 5). That is, the control unit 301 calculates the weight as the sheet bundle.

  If the calculated weight exceeds 60 grams (YES in step S103 in FIG. 5), the control unit 301 determines that the sheet bundle conveyance speed (speed at a constant speed) = high speed and acceleration = large. (Step S104 in FIG. 5). That is, if the sheet bundle is saddle-stitched and integrated and has a further weight, the bundle is less likely to be disturbed by the wind pressure during conveyance, and therefore the sheet bundle is conveyed at high speed and with high acceleration.

  If the calculated weight is 60 grams or less (NO in step S103 in FIG. 5), the control unit 301 determines that the sheet bundle conveyance speed (speed at a constant speed) = medium speed, acceleration = medium, Determination is made (step S105 in FIG. 5). In other words, if the weight of a bundle of sheets that are saddle-stitched and integrated is small, the bundle is more likely to be disturbed by the wind pressure during conveyance than if it is large, so that the bundle of sheets can be conveyed at medium speed and acceleration. Do.

  On the other hand, if saddle stitching is not selected for the sheet bundle and is not integrated (NO in step S101 in FIG. 5), the control unit 301 determines that “weight = sheet weight (unit area weight) × sheet area”. (Step S106 in FIG. 5). That is, the control unit 301 calculates the weight of one sheet.

  If the calculated weight exceeds 10 grams (YES in step S107 in FIG. 5), the control unit 301 determines that the sheet bundle conveyance speed (speed at a constant speed) = medium speed and acceleration = small. (Step S108 in FIG. 5). That is, although a sheet of paper is heavy but not integrated as a bundle of sheets, there is a possibility that the bundle may be disturbed by the wind pressure during conveyance. Therefore, the bundle of sheets is transported at medium speed and low acceleration. .

  On the other hand, if the calculated weight is 10 grams or less (NO in step S107 in FIG. 5), the control unit 301 determines that the sheet bundle conveyance speed (speed at a constant speed) = low speed and acceleration = small. (Step S109 in FIG. 5). That is, since the sheet bundle is not integrated and the weight of the sheet is small, the bundle is likely to be disturbed or displaced by the wind pressure during conveyance. Therefore, the sheet bundle is conveyed at a low speed and with a small acceleration.

  By controlling the sheet bundle conveyance speed as described above, it is possible to maintain the conveyance performance while preventing disturbance of the overlapping state of the sheet bundle during conveyance.

  Here, the high / medium / low speed of the sheet bundle conveyance speed (speed at a constant speed) and the large / medium / small acceleration are relative values in the post-processing apparatus 300. For this reason, the sheet bundle weight of 60 grams and the sheet of 10 grams are values that can be arbitrarily determined depending on the speed and acceleration, the disorder of the sheet bundle, and the allowable range.

  Further, in the flowchart of FIG. 5 described above, the sheet bundle conveyance speed and the acceleration are determined using the determination of whether or not the sheet bundle is integrated, the weight, and the paper size as the sheet bundle state. However, the present invention is not limited to this. Is not to be done. For example, as a determination item of the state of the sheet bundle, it is possible to consider the ease of slipping in addition to the presence / absence of integration of the sheet bundle, the weight, and the paper size. Here, the slipperiness is caused by the coating state and smoothness of the surface, and therefore the paper type (plain paper / coated paper) can be added to the determination item as the state of the sheet bundle.

  Also, slipperiness may be affected by environmental conditions such as humidity. For example, it becomes slippery at low humidity and, conversely, slippery at high humidity. Therefore, it is possible to add environmental conditions (low humidity / medium humidity / high humidity) to the determination items as the state of the sheet bundle. In addition, the slipperiness due to the environmental conditions is closely related to the coating state and smoothness of the paper. Therefore, the environmental conditions may be used by multiplying different coefficients depending on the above-mentioned paper type (plain paper / coated paper). Is possible.

[Speed determination (2)]
In FIG. 6, the sheet bundle conveyance speed and acceleration are determined by determining whether or not the sheet bundle is integrated, the weight, the paper size, and the paper type (slipperiness: plain paper / coated paper) as judgment items. An example of a speed control data table is shown.

  This speed control data table is stored in the storage unit 304 and is used by the control unit 301.

  Further, in the flowchart of FIG. 5, only the presence / absence of sheet bundle and the weight (the amount of weight × area) are determined as judgment items, but in the speed control data table of FIG. 6, the presence / absence of sheet bundle integration, the number, the amount of weight, the area, and the paper type. The conditions are subdivided by dividing each case.

  As a result, the case of sheet bundle integration (saddle-stitched sheet bundle) is classified into nine types, and low speed: small acceleration, low speed: medium acceleration, medium speed: small acceleration, medium speed: medium acceleration, medium speed: Seven types of control are possible: high acceleration, high speed: medium acceleration, high speed: high acceleration, and prevents the paper stack from being disturbed when transporting the integrated paper bundle, while improving transport performance. It can be kept as high as possible.

  In addition, there are four types of cases where there is no sheet bundle integration (half-folded sheet bundle), and three types of control are possible: low speed: low acceleration, medium speed: low acceleration, and medium speed: during acceleration. Thus, it is possible to maintain the conveyance performance as high as possible while preventing the disturbance of the stacking state of the sheet bundle when conveying the unintegrated sheet bundle.

  Although not shown in FIG. 6, it is possible to add environmental conditions (low humidity / medium humidity / high humidity) to the determination items for determining the conveyance speed.

[Speed determination (3)]
Hereinafter, the process for determining the sheet bundle conveyance speed will be described with reference to the flowchart of FIG. Here, as shown in FIG. 3, the saddle-shaped placement unit 351 can convey the sheet bundle Pp in both the Y direction parallel to the fold and the X direction orthogonal to the fold. In this case, a process for calculating a sheet bundle conveyance speed suitable for the parallel direction and the orthogonal method will be described.

  As shown in FIG. 3, when the sheet bundle Pp is transported in the Y direction parallel to the fold line, the entire projected area is small and the air resistance is small. Disturbance occurs. On the other hand, when the sheet bundle Pp is transported in the Y direction orthogonal to the fold line, the air projection increases because the entire projected area is large, and the sheet bundle is disturbed by being displaced from the outer sheet. As described above, since the way of disturbing the sheet bundle differs depending on the difference in the sheet bundle conveying direction, the proper sheet bundle conveying speed that does not cause the disorder is different under the situation where the member that presses down the sheet bundle Pp is not provided. Become.

  The control unit 301 refers to post-processing mode information to check whether or not the sheet bundle generated by folding is integrated by saddle stitching (step S201 in FIG. 7), and the sheet bundle is integrated by saddle stitching. 7 (YES in step S201 in FIG. 7), “weight = number of sheets contained in sheet bundle × sheet weight (unit area weight) × sheet area” is calculated (step S202 in FIG. 7). That is, the control unit 301 calculates the weight as the sheet bundle.

  If the calculated weight exceeds 60 grams (YES in step S203 in FIG. 7), the control unit 301 determines that the sheet bundle conveyance speed (speed at a constant speed) = high in conveyance parallel to the fold line. It is determined that acceleration = large (step S204 in FIG. 7). That is, if the sheet bundle is saddle-stitched and integrated and has a further weight, the bundle is less likely to be disturbed by the wind pressure during conveyance, and therefore the sheet bundle is conveyed at high speed and with high acceleration.

  If the calculated weight is 60 g or less (NO in step S203 in FIG. 7), the control unit 301 determines that the sheet bundle conveyance speed (speed at a constant speed) = medium in the conveyance parallel to the fold line. It is determined that speed and acceleration = medium (step S205 in FIG. 7). In other words, if the weight of a bundle of sheets that are saddle-stitched and integrated is small, the bundle is more likely to be disturbed by the wind pressure during conveyance than if it is large, so that the bundle of sheets can be conveyed at medium speed and acceleration. Do.

If the calculated weight exceeds 60 grams (YES in step S203 in FIG. 7) and the sheet area exceeds 0.125 m ² (YES in step S206 in FIG. 7). ) In the conveyance perpendicular to the fold line, it is determined that the sheet bundle conveyance speed (speed at a constant speed) = medium speed and acceleration = large (step S207 in FIG. 7), and the sheet area is 0.125 m ² or less. If it is determined (NO in step S206 in FIG. 7), the sheet bundle conveyance speed (speed at a constant speed) = high speed and acceleration = high are determined in the conveyance orthogonal to the crease (step S208 in FIG. 7). That is, when transporting in a direction perpendicular to the fold line, even if the sheet bundle is saddle-stitched and integrated, and the weight further increases, the possibility that the bundle is disturbed by the wind pressure (air resistance) at the time of transport is determined by the sheet area. Since they are proportional, the speed and acceleration are determined according to the sheet area.

If the calculated weight is 60 grams or less (NO in step S203 in FIG. 7) and the sheet area exceeds 0.125 m ² (YES in step S209 in FIG. 7), In the conveyance perpendicular to the fold line, it is determined that the sheet bundle conveyance speed (speed at a constant speed) = low speed and acceleration = medium (step S210 in FIG. 7), and if the sheet area is 0.125 m ² or less (FIG. 7). In step S209, NO, the sheet bundle conveying speed (speed at a constant speed) = medium speed and acceleration = medium are determined in the conveyance perpendicular to the fold (step S211 in FIG. 7). That is, when transporting in a direction perpendicular to the fold line, if the sheet bundle is saddle-stitched and integrated and light in weight, the possibility that the bundle is disturbed by the wind pressure (air resistance) during transport is proportional to the sheet area. Therefore, the speed and acceleration are determined according to the sheet area.

  On the other hand, if saddle stitching is not selected for the sheet bundle and is not integrated (NO in step S201 in FIG. 7), the control unit 301 determines that “weight = sheet weight (unit area weight) × sheet area”. (Step S212 in FIG. 7). That is, the control unit 301 calculates the weight of one sheet.

  If the calculated weight exceeds 10 grams (YES in step S213 in FIG. 7), the control unit 301 determines the sheet bundle conveyance speed (speed at a constant speed) = medium speed in the conveyance parallel to the fold. , Acceleration = small is determined (step S214 in FIG. 7). That is, although a sheet of paper is heavy but not integrated as a bundle of sheets, there is a possibility that the bundle may be disturbed by wind pressure (air resistance) during conveyance. Perform bundle transportation.

  On the other hand, if the calculated weight is 10 grams or less (NO in step S213 in FIG. 7), the controller 301 determines that the sheet bundle conveyance speed (speed at a constant speed) = low in conveyance parallel to the fold. , Acceleration = small is determined (step S215 in FIG. 7). That is, since the sheet bundle is not integrated and the weight of the sheet is small, the bundle is likely to be disturbed or displaced by the wind pressure (air resistance k) during conveyance. Transport.

If the calculated weight exceeds 10 grams (YES in step S213 in FIG. 7) and the sheet area exceeds 0.125 m ² (YES in step S216 in FIG. 7). ) In the conveyance perpendicular to the fold line, it is determined that the sheet bundle conveyance speed (speed at a constant speed) = medium speed and acceleration = medium (step S217 in FIG. 7), and if the sheet area is 0.125 m ² or less. (NO in step S216 in FIG. 7), it is determined that the sheet bundle conveyance speed (speed at a constant speed) = high speed and acceleration = medium in the conveyance orthogonal to the crease (step S218 in FIG. 7). That is, when the sheet is conveyed in a direction orthogonal to the crease, the possibility that the bundle is disturbed by the wind pressure (air resistance) at the time of conveyance is proportional to the sheet area, so the speed and acceleration are determined according to the sheet area.

If the calculated weight is 10 grams or less (NO in step S213 in FIG. 7) and the sheet area exceeds 0.125 m ² (YES in step S219 in FIG. 7), In the conveyance perpendicular to the fold line, it is determined that the sheet bundle conveyance speed (speed at a constant speed) = low speed and acceleration = small (step S220 in FIG. 7), and if the sheet area is 0.125 m ² or less (FIG. 7). In step S219, NO, the sheet bundle conveyance speed (speed at a constant speed) = medium speed and acceleration = small are determined in the conveyance perpendicular to the crease (step S221 in FIG. 7). That is, when transporting in a direction orthogonal to the fold line, if the bundle of sheets is not bound and integrated, the possibility that the bundle is disturbed by the wind pressure (air resistance) at the time of conveyance is proportional to the sheet area. The speed and acceleration are determined according to the area.

  As described above, the conveyance direction of the sheet bundle is taken into consideration in relation to the fold, and further, when conveying in the direction orthogonal to the fold, the conveyance is performed by controlling the sheet bundle conveyance speed in consideration of the sheet area. It is possible to maintain the conveyance performance while preventing disturbance of the stacking state of the sheet bundle at the time.

  Here, the high / medium / low speed of the sheet bundle conveyance speed (speed at a constant speed) and the large / medium / small acceleration are relative values in the post-processing apparatus 300. For this reason, the sheet bundle weight of 60 grams and the sheet of 10 grams are values that can be arbitrarily determined depending on the speed and acceleration, the disorder of the sheet bundle, and the allowable range.

  Further, in the flowchart of FIG. 7 described above, the sheet bundle conveyance speed and the acceleration are determined by using the sheet bundle state as the determination items including the presence / absence of integration of the sheet bundle, the weight, the paper size, and the sheet bundle conveyance direction. However, the present invention is not limited to this. For example, as a determination item of the state of the sheet bundle, it is possible to consider the ease of slipping in addition to the presence / absence of integration of the sheet bundle, the weight, the paper size, and the sheet bundle conveyance direction. Here, the slipperiness is caused by the coating state and smoothness of the surface, and therefore the paper type (plain paper / coated paper) can be added to the determination item as the state of the sheet bundle.

  Also, slipperiness may be affected by environmental conditions such as humidity. For example, it becomes slippery at low humidity and, conversely, slippery at high humidity. Therefore, it is possible to add environmental conditions (low humidity / medium humidity / high humidity) to the determination items as the state of the sheet bundle. In addition, the slipperiness due to the environmental conditions is closely related to the coating state and smoothness of the paper. Therefore, the environmental conditions may be used by multiplying different coefficients depending on the above-mentioned paper type (plain paper / coated paper). Is possible.

[Speed determination (4)]
FIG. 8 shows the sheet bundle conveyance speed and the sheet bundle state by determining whether or not the sheet bundle is integrated, weight, paper size, sheet bundle conveyance direction, and paper type (slipperiness: plain paper / coated paper). An example of the speed control data table which determines acceleration is shown.

  This speed control data table is stored in the storage unit 304 and is used by the control unit 301.

  In FIG. 8, the conditions are subdivided from those in the flowchart of FIG. 7 by classifying the sheet area into three levels.

  As a result, the case of sheet bundle integration (saddle-stitched sheet bundle) is classified into 11 types, and the sheet bundle is overlapped when the integrated sheet bundle is conveyed in the crease parallel direction and the crease orthogonal direction. The conveyance performance can be maintained as high as possible while preventing the disturbance of the state.

  Also, there are five types of cases where the sheet bundle is not integrated (half-folded sheet bundle), and the stacking state of the sheet bundle when the unintegrated sheet bundle is conveyed in the crease parallel direction and the crease orthogonal direction. The conveyance performance can be maintained as high as possible while preventing disturbance.

  Although not shown in FIG. 8, it is possible to add environmental conditions (low humidity / medium humidity / high humidity) to the determination items for determining the conveyance speed.

[Other Embodiments]
In the embodiment described above, in the image forming system that transports the paper on which the image is formed in the X direction, the paper bundle with the crease with the Y direction as the ridgeline is transported in the Y direction or the X direction by the paper bundle transport unit 350. However, it is not limited to this.

  That is, a sheet bundle having a crease with the X direction as a ridgeline may be conveyed by the sheet bundle conveying unit 350 in the X direction or the Y direction.

  In the above description, the sheet bundle transport unit 350 has shown the bowl-shaped mounting unit 351. However, a planar trapezoidal mounting unit can also be used. In this case, the flat trapezoidal placement portion may be provided with a convex portion that matches the fold of the sheet bundle.

  Further, the acceleration at the time of determining the sheet bundle conveying speed can be controlled separately for acceleration at acceleration and acceleration at deceleration. In this case, since there is a tendency to be more susceptible to wind pressure during deceleration than during deceleration, the acceleration during acceleration and the acceleration during deceleration may be determined with reference to the sheet area.

  In the above-described paper bundle conveyance speed determination, both the paper bundle conveyance speed (speed at a constant speed) and acceleration are determined by various judgment items based on the state of the paper bundle. It is also possible to variably determine only one of the accelerations and fix the other.

  Further, in each of the above embodiments, when using humidity as an environmental condition, a sensor (not shown) is required. In this case, the sensor may be in the image forming apparatus 100, but it is desirable to provide the sensor in the post-processing apparatus 300 because the humidity also changes as the temperature in the apparatus changes.

  In each of the above embodiments, when an environmental condition such as humidity is used as slipperiness, a coefficient for using the environmental condition may be changed according to the presence or absence of binding. For example, in the case of a bundle of sheets that are not integrated without saddle stitching and are slippery at low humidity, it is possible to make a determination to increase the weight of environmental conditions and determine the conveyance speed. .

  In each of the embodiments described above, three examples of low humidity / medium humidity / high humidity have been shown with respect to the humidity of the environmental condition, but two levels of low humidity that is slippery and other humidity may be used.

  Moreover, although humidity was shown as a specific example as an environmental condition in the above embodiment, it is not limited to this, You may add temperature to judgment conditions. For example, depending on the material of the placement unit 351, when the friction coefficient changes when the temperature changes, it is possible to determine the transport speed by adding the temperature as an environmental condition.

DESCRIPTION OF SYMBOLS 100 Image forming apparatus 101 Control part 102 Communication part 103 Operation display part 130 Image data memory | storage part 140 Image processing part 150 Image formation part 200 Reverse conveyance apparatus 201 Control part 202 Communication part 210 Conveyance part 220 Inversion part 230 Matching part 300 Post-processing apparatus 301 Control Unit 302 Communication Unit 310 Paper Conveying Unit 320 Folding Unit 330 Overlapping Unit 340 Saddle Stitching Unit 350 Paper Bundle Conveying Unit 400 Post-Processing Device

Claims (18)

Controls the folding speed for forming a crease on the sheet, the overlapping section for stacking a plurality of sheets with the creases formed thereon to form a sheet bundle, the conveying section for conveying the sheet bundle, and the conveying speed of the conveying section A post-processing method that transports the image-formed paper and performs post-processing on the paper.
Controlling the transport speed when transporting the sheet bundle according to the state of the sheet bundle and a predetermined condition;
And a post-processing method. The state of the sheet bundle includes whether or not the sheet bundle is integrated, the amount of paper, and the paper size.
The post-processing method according to claim 1. When the paper bundle is integrated, the conveyance speed is controlled by the paper bundle weight determined by the number of sheets, the amount of paper and the paper size constituting the paper bundle,
When the paper bundle is not integrated, the transport speed is controlled by the weight of one paper determined by the amount of paper and the paper size constituting the paper bundle;
The post-processing method according to claim 2. The state of the sheet bundle includes a surface state relating to slipperiness of the sheets constituting the sheet bundle, and the conveyance speed is controlled in consideration of the surface state.
The post-processing method according to claim 2-3. The transport unit includes a placement unit that supports a lower-angle portion of the fold of the paper from below, and transports the paper bundle in a state of being placed on the placement unit.
The post-processing method as described in any one of Claims 1-4 characterized by the above-mentioned. The transport unit is in a state in which the sheet bundle is placed on the placement unit, and transports the sheet bundle without restraining it from above;
The post-processing method according to claim 5. In the transport unit, the placement unit includes a collar-shaped collar portion that supports an inferior angle portion of the fold of the sheet from below.
The post-processing method according to claim 5-6. The transport unit is capable of transporting in a parallel direction and a perpendicular direction of the folds of the sheet bundle,
The state of the sheet bundle further includes a relationship between the direction of the crease and the conveyance direction,
The post-processing method as described in any one of Claims 1-7 characterized by the above-mentioned. The control of the transport speed includes at least one of control about acceleration and speed control during transport at a constant speed.
The post-processing method according to claim 1, wherein the post-processing method is performed. A fold forming a crease on the paper;
A stacking unit that stacks a plurality of the creased sheets to form a sheet bundle;
A transport unit for transporting the sheet bundle;
A control unit for controlling the conveyance speed of the conveyance unit,
A post-processing device that transports image-formed paper and performs post-processing on the paper,
The control unit controls the conveyance speed when the conveyance unit conveys the sheet bundle according to a state of the sheet bundle and a predetermined condition.
A post-processing device. The control unit controls the conveyance speed with reference to the presence / absence of integration of the paper bundle, the amount of paper, and the paper size as the state of the paper bundle,
The post-processing apparatus according to claim 10. The controller is
When the paper bundle is integrated, the conveyance speed is controlled by the paper bundle weight determined by the number of sheets, the amount of paper and the paper size constituting the paper bundle,
When the paper bundle is not integrated, the transport speed is controlled by the weight of one paper determined by the amount of paper and the paper size constituting the paper bundle;
The post-processing apparatus according to claim 11. The control unit further refers to a surface state relating to slipperiness of sheets constituting the sheet bundle as the state of the sheet bundle, and controls the transport speed in consideration of the surface state.
The post-processing apparatus according to claim 11, wherein the post-processing apparatus is a post-processing apparatus. The transport unit includes a placement unit that supports a lower-angle portion of the fold of the paper from below, and transports the paper bundle in a state of being placed on the placement unit.
The post-processing device according to any one of claims 10 to 13, The transport unit is in a state in which the sheet bundle is placed on the placement unit, and transports the sheet bundle without restraining it from above;
The post-processing apparatus according to claim 14. In the transport unit, the placement unit includes a collar-shaped collar portion that supports an inferior angle portion of the fold of the sheet from below.
The post-processing apparatus according to claim 14-15. The transport unit is capable of transporting in a parallel direction and a perpendicular direction of the folds of the sheet bundle,
The control unit controls the conveyance speed when the conveyance unit conveys the sheet bundle, taking into account the relationship between the direction of the crease and the conveyance direction as the state of the sheet bundle.
The post-processing apparatus according to any one of claims 10 to 16, The control unit includes at least one of control about acceleration and control of speed at the time of transport at a constant speed as the transport speed control.
The post-processing apparatus according to any one of claims 10 to 17,