Abstract: An image forming apparatus, to which an accessory device is connectable, includes a control unit configured to control the image forming apparatus to start a preparation operation in which an image forming unit can form an image in response to a power supply, and a storage unit configured to store a connecting state between the image forming apparatus and the accessory device. The control unit determines, in response to the start of the power supply, whether the accessory device has been connected to the image forming apparatus before the power supply is stopped, with reference to information stored in the storage unit. Then, the control unit controls the image forming apparatus to start the preparation operation without waiting for the receiving of the information about the accessory device therefrom if the accessory device has not been connected to the image forming apparatus.

Abstract: When information about weight of a sheet indicates weight less than a predetermined weight, a sheet stacking apparatus configured to align sheets to be stacked on a stacking tray discharges the sheet onto the stacking tray while overlapping the sheet with another sheet by an overlapping unit, and, when the information about the weight of the sheet indicates weight not less than the predetermined weight, the sheet stacking apparatus discharges the sheet onto the stacking tray without overlapping the sheet with another sheet by the overlapping unit.

Abstract: A printing system includes, for example, a printing apparatus which forms an image on a sheet, and a plurality of dollies which are assigned different dolly identification information and used to stack the sheet discharged from the discharging port of the printing apparatus. The printing system also includes a designation unit which designates a dolly to be used for a print job, and an output unit which outputs alert information when the dolly designated by the designation unit is not allocated at the discharging port.

Abstract: A sheet buffer apparatus retains a sheet to be conveyed to a post-processing unit and is configured to perform post-processing for a sheet. The apparatus comprises a buffer unit configured to perform buffer processing to retain a sheet to be conveyed to the post-processing unit and overlay the sheet to be retained and a succeeding sheet, a determination unit configured to determine whether a sheet is inhibited from the buffer processing by the buffer unit, and a control unit configured, when the determination unit determines that the sheet succeeding the sheet to be retained is a sheet for which the buffer processing is inhibited, to control the buffer unit not to perform the retaining of the sheet to be retained.

Abstract: A plate for a magnet cylinder includes a main body, a nonmagnetic portion, and a magnetic piece. The main body is formed of a flexible thin plate-like magnetic material to be magnetically mounted on the outer surface of a magnet cylinder. The nonmagnetic portion is projected from one end of the main body. The magnetic piece magnetically sandwiches the nonmagnetic portion against the outer surface of the magnet cylinder.

Abstract: When information about weight of a sheet indicates weight less than a predetermined weight, a sheet stacking apparatus configured to align sheets to be stacked on a stacking tray discharges the sheet onto the stacking tray while overlapping the sheet with another sheet by an overlapping unit, and, when the information about the weight of the sheet indicates weight not less than the predetermined weight, the sheet stacking apparatus discharges the sheet onto the stacking tray without overlapping the sheet with another sheet by the overlapping unit.

Abstract: A sheet stacking apparatus includes an alignment member to align a sheet stacked on a stacking tray in a width direction perpendicular to a direction in which the sheet is discharged. When stacking a plurality of sheets on the stacking tray, the sheet stacking apparatus lowers the stacking tray, so that a predetermined distance is maintained between the top surface sheet and a sheet discharge port. If the stacking tray is lowered to a predetermined position while the alignment unit is executing an alignment operation at a first position, the sheet stacking apparatus lowers the alignment member to a second position lower than the first position and causes the alignment member to execute the alignment operation at the second position.

Abstract: A sheet stacking apparatus includes a discharge unit, a stacking tray, an acquisition unit, a shift control unit, and an alignment unit. The shift control unit controls a stacking position of a sheet in a sheet width direction in response to shift information acquired by the acquisition unit. The alignment unit aligns a sheet staked on the stacking tray and moves to a position that abuts on a side edge of the sheet in the sheet width direction to align the sheet. The shift control unit controls a stacking position of a second sheet to stack the second sheet on a second position or on a first position depending on where a first sheet is stacked and on shift information of the second sheet.

Abstract: A sheet buffer apparatus retains a sheet to be conveyed to a post-processing unit and is configured to perform post-processing for a sheet. The apparatus comprises a buffer unit configured to perform buffer processing to retain a sheet to be conveyed to the post-processing unit and overlay the sheet to be retained and a succeeding sheet, a determination unit configured to determine whether a sheet is inhibited from the buffer processing by the buffer unit, and a control unit configured, when the determination unit determines that the sheet succeeding the sheet to be retained is a sheet for which the buffer processing is inhibited, to control the buffer unit not to perform the retaining of the sheet to be retained.

Abstract: A sheet stacking apparatus includes a stack unit which includes a first stack tray and a second stack tray which can be individually elevated and is configured to stack a sheet on at least one of the first stack tray and the second tray, and a control unit configured to control the stack unit to stack the sheet in a first stack mode in which the sheet is stacked on at least one of the first stack tray and the second stack tray without being extended over the first stack tray and the second stack tray and a second stack mode in which the sheet is stacked on across the first stack tray and the second stack tray, the control unit capable of selecting the first stack mode and the second stack mode with respect to a same size sheet.

Abstract: Discharging a sheet bundle of a sheet N and a sheet N?1 on preceding sheets already stacked on a stacking tray can cause the already-stacked sheets to be pushed out by the front end of the succeeding sheets. By pressing already-stacked sheets with a bundle pressing member when a sheet bundle of succeeding sheets is discharged, it is possible to reduce the likelihood of the already-stacked sheets being pushed out. Employing the bundle pressing member reduces disturbance of sheet alignment that can occur when a sheet bundle is discharged on already-stacked sheets.

Abstract: A sheet buffer apparatus which retains a sheet to be conveyed to a post-processing unit configured to perform post-processing for a sheet, the apparatus comprises: a buffer unit configured to perform buffer processing to retain a sheet to be conveyed to the post-processing unit and overlay the sheet to be retained and a succeeding sheet; a determination unit configured to determine whether a sheet is inhibited from the buffer processing by the buffer unit; and a control unit configured, when the determination unit determines that the sheet succeeding the sheet to be retained is a sheet for which the buffer processing is inhibited, to control the buffer unit not to perform the retaining of the sheet to be retained.

Abstract: An image forming apparatus that enables to execute a bookbinding process for sheet bundles without decreasing productivity. The image forming apparatus is connected to a bookbinding apparatus having a bookbinding unit that binds a book by attaching a ring to a punch hole and a buffer unit that performs a buffering process to convey sheets in piles so that sheets for a next sheet bundle are not ejected onto a sheet bundle that is being processed by the bookbinding unit. A determination unit determines whether a sheet is a type that is prohibited from buffering. A control unit adjusts an ejection order so that the sheet of the type that is prohibited from buffering is not ejected within the predetermined number of sheets from the first sheet of sheets that constitute the sheet bundle, when the determination unit determines that the sheet is the type that is prohibited from buffering.

Abstract: A finisher includes an intermediate tray that collects sheets to form a sheet bundle, a sheet gripping member that grips one end of the sheet bundle in a conveying direction and a positioning member that grips the other end of the sheet bundle in a conveying direction, a moving portion that moves the sheet gripping member and the positioning member to come close to each other, a pair of folding rollers that folds the sheet bundle while conveying the sheet bundle, a projecting member that projects a part between the one end and the other end of the gripped sheet bundle toward the pair of folding rollers, and a controller that controls the moving portion, such that the sheet gripping member and the positioning member come close to each other in synchronization with an operation of projecting the projecting member toward the sheet bundle.

Abstract: A bookbinding system includes an image forming apparatus and a bookbinding apparatus connected to the image forming apparatus. The bookbinding system includes an image forming unit to form an image on a recording sheet; a loading unit to load, as a bookblock stack, plural recording sheets on which images are formed; a bonding unit to form a booklet by bonding a cover with the bookblock stack; a setting unit to set a bookblock size, a cover size, and a finishing size; a cutting unit to cut the booklet bonded together with the cover into the finishing size; a stack thickness detection unit to detect a thickness of the bookblock stack; and a bookbinding permission/inhibition determination unit to determine permission/inhibition of a bookbinding operation based on a stack thickness detection result as well as the bookblock size, the cover size, and the finishing size set by the setting unit.

Abstract: A sheet stacking apparatus includes a discharge unit, a stacking tray, an acquisition unit, a shift control unit, and an alignment unit. The shift control unit controls a stacking position of a sheet in a sheet width direction in response to shift information acquired by the acquisition unit. The alignment unit aligns a sheet staked on the stacking tray and moves to a position that abuts on a side edge of the sheet in the sheet width direction to align the sheet. The shift control unit controls a stacking position of a second sheet to stack the second sheet on a second position or on a first position depending on where a first sheet is stacked and on shift information of the second sheet.

Abstract: When information about weight of a sheet indicates weight less than a predetermined weight, a sheet stacking apparatus configured to align sheets to be stacked on a stacking tray discharges the sheet onto the stacking tray while overlapping the sheet with another sheet by an overlapping unit, and, when the information about the weight of the sheet indicates weight not less than the predetermined weight, the sheet stacking apparatus discharges the sheet onto the stacking tray without overlapping the sheet with another sheet by the overlapping unit.

Abstract: A sheet stacking apparatus includes an alignment member to align a sheet stacked on a stacking tray in a width direction perpendicular to a direction in which the sheet is discharged. When stacking a plurality of sheets on the stacking tray, the sheet stacking apparatus lowers the stacking tray, so that a predetermined distance is maintained between the top surface sheet and a sheet discharge port. If the stacking tray is lowered to a predetermined position while the alignment unit is executing an alignment operation at a first position, the sheet stacking apparatus lowers the alignment member to a second position lower than the first position and causes the alignment member to execute the alignment operation at the second position.

Abstract: A sheet conveying system which is capable of preventing a jammed sheet from being mixed with processed sheets, reducing waste in sheets and toners, and further alleviating the user's operations, when jamming has occurred during passing of a sheet between respective sheet conveying devices of upstream and downstream apparatuses. A puncher control section of a puncher as an upstream apparatus of the system issues a passing completion notification as to the passing of a sheet to a staple stacker control section of a staple stacker as a downstream apparatus of the system. Upon reception of the notification, when the staple stacker control section determines that the parameter of auxiliary information of the notification indicates an abnormal discharge of the sheet from the puncher, the staple stacker stops the conveyance of the sheet.

Abstract: A bookbinding apparatus which makes it possible to shorten a time period required to heat an adhesive when the power of the bookbinding apparatus is turned on again. A glue preparation section heats glue. A glue applying section applies the heated glue to a recording sheet bundle. A CPU of the bookbinding apparatus determines at the power-on of the apparatus whether or not there is a recording sheet bundle to which glue is to be applied within the apparatus. When there is no such recording sheet bundle, the glue applying section applies glue to a recording sheet bundle after the temperature of the glue has reached a first target temperature, whereas when there is such a recording sheet bundle, the glue applying section applies the glue to the recording sheet bundle after the glue temperature has reached a second target temperature lower than the first target temperature.