Booklet making device and image forming system

Abstract

To provide a booklet making device and an image forming system that optimize distribution of pressure applied to sheets in the longitudinal direction of a heating and pressing unit for multiple sheet sizes.SOLUTION: When the region of a heating and pressurizing unit in the longitudinal direction where the heating and pressurizing unit heats and pressurizes a maximum size sheet is defined as a first region, the region in the longitudinal direction where the heating and pressurizing unit heats and pressurizes a minimum size sheet is defined as a second region, and the region of the heating and pressurizing unit that is inside the first region and outside the second region in the longitudinal direction is defined as a third region, the minimum value of pressure in the longitudinal direction applied to the sheet when the heating and pressurizing unit heats and pressurizes the maximum size sheet is located at a position within the third region or at an end position of the second region adjacent to the third region, and there is a region within the third region, in the longitudinal direction, on the opposite side from the side where the second region is located with respect to the position of the minimum value, where a pressure greater than the minimum value is applied.SELECTED DRAWING: Figure 11

Description

[Technical field]

[0001] The present invention relates to a booklet producing apparatus that produces a booklet by bonding a plurality of recording materials together, and to an image forming system that has the booklet producing apparatus. [Background technology]

[0002] A method is known in which, as in Patent Document 1, a booklet is produced by remelting adhesive toner in a booklet production device to adhere the sheets to each other after a sheet stack consisting of multiple sheets that have been subjected to image formation processing by an image forming device such as a printer or copier, thereby producing a booklet. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2010-111025 A Summary of the Invention [Problem to be solved by the invention]

[0004] When an image forming apparatus and a booklet producing apparatus are made compatible with a plurality of sheet sizes, the thermocompression means of the booklet producing apparatus must be configured to be capable of heating and pressing the largest sheet size (large size paper). In a heating and pressing unit that uniformly distributes pressure in the longitudinal direction when pressing large size paper, when pressing a sheet size (small size paper) smaller than the large size paper, the pressure is concentrated on the edge of the small size paper. As a result, there is a concern that the pressure other than the edge of the small size paper will be reduced.

[0005] The present invention has been made in consideration of the above-mentioned problems, and aims to provide a booklet production device and an image forming system that optimizes the distribution of pressure applied to sheets in the longitudinal direction of a heating and pressurizing unit for a variety of sheet sizes. [Means for solving the problem]

[0006] The present invention is a booklet production device that includes an elongated heating and pressing unit that heats and presses an adhesive layer formed on a plurality of overlapping sheets, the heating and pressing unit having a pressure plate that contacts and presses the sheets, a heating body that heats the pressure plate, a receiving member that faces the pressure plate, and a pressure mechanism that applies pressure to the sheets sandwiched between the pressure plate and the receiving member, and that sandwiches a plurality of sheets with adhesive layers formed thereon between the pressure plate and the receiving member and heats and presses the adhesive layers formed on the sheets to produce a booklet, and a region of the heating and pressing unit in the longitudinal direction of the heating and pressing unit in which the heating and pressing unit heats and presses a sheet of maximum size is defined as The present invention is characterized in that, when the area of ​​the heating and pressurizing unit in the longitudinal direction where the heating and pressurizing unit heats and pressurizes a sheet of a minimum size is defined as the first area, the area of ​​the heating and pressurizing unit in the longitudinal direction which is inside the first area and outside the second area in the longitudinal direction is defined as the third area, the minimum value of the pressure applied to the sheet when the heating and pressurizing unit heats and pressurizes a sheet of a maximum size in the longitudinal direction is a position within the third area or an end position of the second area adjacent to the third area, and there is a region within the third area, in the longitudinal direction, on the opposite side to the side where the second area is located as viewed from the position of the minimum value, where the pressure applied is greater than the minimum value. Effect of the Invention

[0007] It is possible to provide a booklet producing apparatus and an image forming system that can optimize the distribution of pressure applied to sheets in the longitudinal direction of a heating and pressing unit for a plurality of sheet sizes. [Brief description of the drawings]

[0008] [Figure 1] Schematic diagram of an image forming apparatus according to a first embodiment. [Diagram 2] FIG. 1 is a diagram showing a toner image formed on a sheet by an image forming apparatus according to a first embodiment; [Diagram 3] Measurement results of toner storage modulus [Figure 4]FIG. 1 is a diagram showing a buffer unit of a booklet production apparatus according to a first embodiment; [Diagram 5] 5A to 5H are diagrams showing the operation of the buffer unit according to the first embodiment; [Figure 6] FIG. 1 is a diagram showing an alignment unit of a booklet production apparatus according to a first embodiment; [Figure 7] FIG. 1 is a diagram showing a movable unit of an alignment section according to the first embodiment; [Figure 8] 5A to 5D are diagrams showing the operation of the matching unit according to the first embodiment; [Figure 9] FIG. 1 is a diagram for explaining a heating and pressurizing unit according to the first embodiment. [Figure 10] 1A to 1F are diagrams showing the operation of the heating and pressurizing unit according to the first embodiment. [Figure 11] FIG. 1 is a diagram showing a pressurizing state of a heating and pressurizing unit according to the first embodiment; [Figure 12] FIG. 13 is a diagram showing a pressurized state of a heating and pressurizing unit according to Comparative Example 1. [Figure 13] FIG. 13 is a diagram showing a pressurized state of a heating and pressurizing unit according to Comparative Example 2. [Figure 14] Schematic diagram showing the booklet adhesive strength test method [Figure 15] Booklet adhesive strength test results [Figure 16] FIG. 13 is a diagram showing a pressurizing state of the heating and pressurizing unit according to the second embodiment. [Figure 17] 13A to 13B are diagrams showing the operation of a matching unit according to the third embodiment; [Figure 18] FIG. 13 is a diagram showing a pressurizing state of the heating and pressurizing unit according to the third embodiment. [Figure 19] FIG. 13 is a diagram showing a pressurized state of a heating and pressurizing unit according to Comparative Example 3. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the present invention, the term "image forming apparatus" broadly includes apparatuses that form (record) images on recording materials (recording media), such as single-function printers, copying machines, multifunction machines, and commercial printing machines. In addition, a system in which an image forming apparatus is connected to a booklet making apparatus that makes booklets by bonding multiple recording materials together is called an image forming system. EXAMPLES

[0010] The configuration of an image forming apparatus having a sheet material conveying device according to the present invention will be described with reference to Figs. 1 to 10. The present invention is not limited to the following embodiments, and other configurations may be substituted within the scope of the concept of the present invention. The image forming apparatus and booklet producing apparatus of this embodiment will be described with reference to Fig. 1. Fig. 1 is a schematic diagram showing a cross section of an image forming apparatus 101 and booklet producing apparatus 106 according to the first embodiment. The image forming apparatus 101 and the booklet producing apparatus 106 are combined to form an image forming system 100. Note that the image forming system 100 may include a form in which part or all of the booklet producing function is incorporated in the image forming apparatus 101.

[0011] In the image forming system 100 of this embodiment, an image is formed on each sheet S by the image forming apparatus 101, and a plurality of sheets S are thermocompression bonded in a booklet making apparatus 106, thereby making it possible to produce a booklet that has been printed and bound in a single apparatus. Note that a variety of sheet materials of different sizes and materials can be used as the sheet S, including paper such as plain paper or thick paper, sheet materials with surface treatments such as coated paper, plastic film, cloth, and sheet materials of special shapes such as envelopes and index paper. Here, the sheet conveying speed in this embodiment is 300 mm / sec. The maximum basis weight of the sheet S is 90 g / m 2 It is.

[0012] (Image forming device body) The image forming apparatus 101 is an electrophotographic apparatus including a housing 101A and an image forming unit 101B of an electrophotographic type housed inside the housing 101A. The image forming unit 101B is an electrophotographic unit of an intermediate transfer type, and includes a primary transfer roller 107, an intermediate transfer belt 108 as an intermediate transfer body, and a process cartridge 195 arranged along the intermediate transfer belt 108. The process cartridge 195 includes a photosensitive drum 102 as an image carrier, a charging device 103 as a charging means, and a developing unit 105 as a developing means. The image forming unit 101B also includes a scanner unit 104 as an exposure means. The developing unit 105 includes a developing roller 105a as a developing means, and a toner container 105b that contains toner (developer). The developing roller 105a is rotatably held by the toner container 105b.

[0013] The process cartridge 195 is detachably attached to the housing 101A. A toner cartridge 196 containing toner to be supplied to the developing unit 105 is detachably attached to the image forming device 101. The "housing 101A" of the image forming device 101 refers to a portion of the image forming device 101 excluding the process cartridge 195 and the toner cartridge 196. The housing 101A includes frame members such as a metal frame constituting the frame of the image forming device 101 and members fixed to the frame, and forms a mounting space in which the process cartridge 195 and the toner cartridge 196 are mounted. The process cartridge 195 uses toner to create a toner image for recording an image on a sheet S, and also creates an adhesive toner image as a powder adhesive for adhering the sheets S together. The image forming device 101 of this embodiment has a monochrome printer configuration for recording monochrome images. The image forming device 101 uses black toner not only for recording images but also as an adhesive toner (adhesive). In this embodiment, the monochrome printer configuration is described with only one cartridge and toner for both recording and adhesion, but the present invention is not limited to this, and toner dedicated to adhesion may be used. Also, a configuration in which multiple cartridges can be installed so that multiple color images can be formed and booklets can be adhered to each other may be used. In this case, the toner for adhesion does not have to be black toner, and may be a toner dedicated to adhesion that is different from the toner used for image recording.

[0014] The toner cartridge 196 and the process cartridge 195 mounted in the housing 101A are connected via a toner transport pipe 197. The toner cartridge 196 can supply toner to the developing unit 105 via the toner transport pipe 197. A cassette 113a (also called a sheet tray or storage) serving as a storage section for storing sheets S used in image formation is mounted below the scanner unit 104 so as to be removable from the housing 101A. Furthermore, one or more optional sheet feeding devices 130 including an additional cassette 113b may be connected below the housing 101A.

[0015] The intermediate transfer belt 108 is a movable (rotatable) endless belt stretched around a drive roller 109a, a tension roller 109b, and a tension roller 110 that rotate around parallel axes. The intermediate transfer belt 108 moves (rotates, conveys) counterclockwise in the figure by the rotation of the drive roller 109a. A primary transfer roller 107 as a primary transfer member is disposed on the inner peripheral side of the intermediate transfer belt 108 at a position facing the photosensitive drum 102 via the intermediate transfer belt 108. A secondary transfer roller 111 as a secondary transfer member is disposed on the outer peripheral side of the intermediate transfer belt 108 at a position facing the drive roller 109a via the intermediate transfer belt 108. A secondary transfer portion is formed as a nip portion between the intermediate transfer belt 108 and the secondary transfer roller 111 and as a transfer portion. The intermediate transfer belt 108, the primary transfer roller 107, and the secondary transfer roller 111 are transfer means for transferring the toner image formed on the photosensitive drum 102, which is an image carrier, to the sheet S. A belt cleaner 112 is provided at a position facing the tension roller 110 across the intermediate transfer belt 108 as a cleaning means for cleaning the intermediate transfer belt 108. The belt cleaner 112 includes a cleaning member 112a such as a blade or a brush arranged in contact with the intermediate transfer belt 108, and a waste toner container 198 as a collection container. The belt cleaner 112 removes deposits such as transfer residual toner from the intermediate transfer belt 108 by the cleaning member 112a, and collects them in the waste toner container 198. A fixing device 118 is provided above the secondary transfer section in the housing 101A as a fixing device. The fixing device 118 has a thermal fixing configuration in which a toner image is fixed by heating. The fixing device 118 has a pair of rotating bodies (e.g., a pair of rollers consisting of a fixing roller and a pressure roller) that clamp and transport the sheet S, and a heat source (e.g., a halogen lamp or an induction heating mechanism) that heats the toner image on the sheet S via the fixing roller.

[0016] (Image formation operation) When the image forming apparatus 101 performs an image forming operation, a sheet S is fed by a feeding roller 114 as a feeding means from a cassette 113 at the bottom of the housing 101A or from a cassette 113 of the sheet feeding device 130. A separation roller pair 115 separates and conveys the fed sheets S one by one. The sheet S is conveyed by a drawing roller 116 toward a registration roller pair 117, and the leading edge of the sheet S hits a nip portion of the registration roller pair 117 in a stopped state, thereby correcting skew of the sheet S. The registration roller pair 117 sends the sheet S to a secondary transfer portion at a timing synchronized with the progress of the toner image creation process by the image forming portion 101B.

[0017] On the other hand, in the image forming section 101B, the photosensitive drum 102 and the intermediate transfer belt 108 rotate. The charging device 103 uniformly charges the surface of the photosensitive drum 102. The scanner unit 104 irradiates the photosensitive drum 102 with laser light based on image information representing an image to be recorded on the sheet S, and writes an electrostatic latent image. The developing unit 105 develops this electrostatic latent image with black toner, and the developing unit 105 develops (visualizes) this electrostatic latent image as a black toner image. Here, when the booklet making device 106 performs thermocompression bonding, which will be described later, the scanner unit 104 irradiates the photosensitive drum 102 with laser light based on information indicating the bonding position of the sheet S, and writes an electrostatic latent image. The developing unit 105 develops this electrostatic latent image with black toner, and an adhesive toner image is formed in an area on the photosensitive drum 102 corresponding to the bonding position on the sheet S.

[0018] The toner image formed on the photosensitive drum 102 is transferred (primary transfer) to the intermediate transfer belt 108 by the primary transfer roller 107, and is transported toward the secondary transfer section as the intermediate transfer belt 108 rotates. Then, in the secondary transfer section, a voltage is applied to the secondary transfer roller 111, so that the toner image is transferred (secondary transfer) to the sheet S fed from a pair of registration rollers 117. The sheet S that has passed through the secondary transfer section is sent to a fixing device 118, and the toner image is heated while passing through a nip portion between a fixing roller and a pressure roller, softening the toner, and then the toner is fixed to the sheet S.

[0019] The sheet S that has passed through the fixing device 118 has its conveying path switched by the switching unit 119. In the case of single-sided printing, the sheet S is guided to a discharge path 190 by the switching unit 119, and is discharged from the housing 101A by a pair of discharge rollers 191. In this embodiment, the image forming apparatus 101 is connected to the booklet production apparatus 106 via a relay conveying unit 192. The sheet S discharged from the pair of discharge rollers 191 is delivered to the booklet production apparatus 106 via a pair of conveying rollers 193 and 194 of the relay conveying unit 192. In addition, when the relay conveying unit 192 and the booklet production apparatus 106 are not connected, the pair of discharge rollers 191 discharges the sheet S as a product onto a stacking tray 135 provided at the top of the housing 101A. In the case of double-sided printing, the sheet S with an image formed on the first side is guided to a pair of reversing rollers 199 by the switching unit 119. Then, the sheet S is reversed and conveyed (switchback conveyed) by a pair of reversing rollers 199, and then conveyed toward a pair of registration rollers 117 via a double-sided conveying path 218. The sheet S passes through a secondary transfer unit and a fixing device 118, whereby an image is formed on a second side opposite to the first side, and then the sheet S is discharged from the housing 101A by a pair of discharge rollers 191.

[0020] 2(a) is a schematic diagram showing an example of a toner image formed on a sheet S. On the illustrated sheet S, a toner image (recording toner image) 38 for recording an image such as text, a figure, or a photograph, and a toner image (adhesive toner image) 39 for adhering sheets together are formed. In this embodiment, the width Tw of the adhesive toner image 39 is 4.0 mm, and the toner amount (laying amount) per unit area is 0.40 mg / cm. 2 The toner amount was measured after the secondary transfer and in an unfixed state before the fixing process. The position, shape, area, etc. of the adhesive toner image 39 can be changed according to the configuration of the heating and pressing unit 167 described later and the size of the sheet S. When the image forming apparatus 101 creates a booklet, in this embodiment, the adhesive toner image 39 is basically formed on both sides of the sheet S (excluding the front and back covers of the booklet). FIG. 2(b) shows an image layout of eight sides (4 sheets x 2 sides) when a double-sided four-sheet booklet is created using the sheet S of this embodiment. In this embodiment, the adhesive toner image 39 is formed on six sides, excluding the front cover (front side of the first side) and the back cover (reverse side of the fourth side). Here, in this embodiment, double-sided printing is assumed, but this is not limited thereto, and for example, the adhesive toner image 39 may be formed only on the front side of the sheet.

[0021] <Toner composition, manufacturing method, and measurement method> Next, the constitution of the toner mainly composed of thermoplastic resin used in this embodiment will be described. Examples of the thermoplastic resin include polyester resin, vinyl resin, acrylic resin, styrene-acrylic resin, polyethylene, polypropylene, polyolefin, ethylene-vinyl acetate copolymer resin, ethylene-acrylic acid copolymer resin, etc. A plurality of these resins may be contained. The toner preferably further contains wax. As the wax, known waxes such as ester waxes, which are esters of alcohol and acid, and hydrocarbon waxes such as paraffin wax can be used. The toner contains a black colorant, and may contain a magnetic material, a charge control agent, wax, and an external additive. In order to form an adhesive portion of toner on a sheet using an electrophotographic method, the weight average particle diameter of the toner is preferably 5.0 μm or more and 30 μm or less, more preferably 6.0 μm or more and 20 μm or less.

[0022] An example of toner production will be described. Styrene 75.0 parts N-Butyl acrylate 25.0 parts Polyester resin 4.0 parts (Polyester resin with weight average molecular weight (Mw) of 20,000, glass transition temperature (Tg) of 75°C, and acid value of 8.2 mgKOH / g) Ethylene glycol distearate 14.0 parts (Ester wax made by esterifying ethylene glycol and stearic acid) Hydrocarbon wax (HNP-9, Nippon Seiro) 2.0 parts Divinylbenzene 0.5 parts The mixture of the above materials was kept at 60°C, and was stirred at 500 rpm using a TK homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.) to dissolve uniformly, and a polymerizable monomer composition was prepared. Meanwhile, 850.0 parts of 0.10 mol / L-Na3PO4 aqueous solution and 8.0 parts of 10% hydrochloric acid were added to a container equipped with a high-speed stirring device Clearmix (manufactured by M-Technique Co., Ltd.), the rotation speed was adjusted to 15,000 rpm, and the mixture was heated to 70°C. 127.5 parts of 1.0 mol / L-CaCl2 aqueous solution were added thereto to prepare an aqueous medium containing a calcium phosphate compound. After the above polymerizable monomer composition was added to the aqueous medium, 7.0 parts of t-butyl peroxypivalate, a polymerization initiator, was added, and the mixture was granulated for 10 minutes while maintaining the rotation speed at 15,000 rpm. Thereafter, the agitator was changed from the high-speed agitator to a propeller agitator, and the mixture was reacted at 70°C for 5 hours while refluxing, and then the liquid temperature was increased to 85°C and the mixture was reacted for an additional 2 hours. After the polymerization reaction was completed, the obtained slurry was cooled, and hydrochloric acid was added to the slurry to adjust the pH to 1.4, and the mixture was stirred for 1 hour to dissolve the calcium phosphate salt. The mixture was then washed with three times the amount of water as the slurry, filtered, dried, and classified to obtain toner particles. Then, silica fine particles (number average particle size of primary particles: 10 nm, BET specific surface area: 170 m) that had been hydrophobized using dimethyl silicone oil (20% by mass) as an external additive were added per 100.0 parts of the toner particles. 2 The mixture was mixed at 3000 rpm for 15 minutes using a Mitsui Henschel mixer (manufactured by Mitsui Miike Chemical Engineering Co., Ltd.) to obtain a toner. The weight average particle diameter of the obtained toner was 7.0 μm.

[0023] The method for measuring the storage modulus as a viscoelastic property of toner is described below. The storage modulus of toner is measured using a dynamic viscoelasticity measuring device (rheometer) ARES (manufactured by Rheometrics Scientific). Measurement tool: A serrated parallel plate with a diameter of 7.9 mm is used.

[0024] Measurement sample: Using a pressure molding machine, mold a 0.1g test piece into a cylindrical sample with a diameter of 8 mm and a height of 2 mm (maintain 15kN for 1 minute at room temperature). The pressure molding machine used is a 100kN press NT-100H manufactured by NPa Systems.

[0025] The temperature of the serrated parallel plate is adjusted to 120°C, the cylindrical sample is heated and melted, the sawtooth is inserted, and a load is applied vertically so that the axial force does not exceed 30 (gf) (0.294N) to fix it to the serrated parallel plate. A steel belt may be used at this time so that the diameter of the sample is the same as that of the parallel plate. The serrated parallel plate and the cylindrical sample are slowly cooled down to the measurement start temperature of 30.00°C over one hour.

[0026] Measurement frequency: 6.28 rad / sec Measurement distortion setting: Set the initial value to 0.1%, and perform the measurement in automatic measurement mode.

[0027] Sample elongation correction: Adjusted in automatic measurement mode.

[0028] Measurement temperature: 30°C to 140°C at a rate of 2°C per minute.

[0029] Measurement interval: Measure viscoelastic data every 30 seconds, i.e., every 1°C.

[0030] Figure 3 shows the results of measuring the storage modulus of the toner. The representative value is the storage modulus at 100°C, Ga'(100°C)=2.2×10 4 Pa, storage modulus at 80°C Ga'(80°C) = 3.2 x 10 5 The value at 100° C. was selected because the toner on the sheet S during fixing is heated to about 100° C. while passing through the fixing nip 6N of the fixing device 118. The value at 80° C. was selected because the minimum toner temperature is about 80° C. when a maximum of five sheets are bonded at once during the bonding process of a sheet stack by the heating and pressurizing unit 167. (Booklet production device) In FIG. 1, the booklet production device 106 includes a buffer section 120 as a buffer means for stacking a plurality of sheets S, an alignment section 156 as an alignment means for aligning the plurality of sheets S, and a heating and pressurizing unit 167 for thermocompression bonding the sheets S together. The heating and pressurizing unit 167 is an example of a sheet bonding device (adhesive unit, adhesive means, thermocompression bonding means, lamination processing section) for bonding the sheets together. The booklet production device 106 also includes an upper discharge tray 125 and a lower discharge tray 137 that can be raised and lowered as discharge destinations for discharging the results of the image forming device 101. The booklet production device 106 is a booklet production device that receives a plurality of sheets S on which images are formed one by one by the image forming device 101, performs a bonding process (thermocompression bonding) and discharges them as a sheet bundle (booklet). The buffer section 120, the alignment section 156, and the heating and pressurizing unit 167 will be described in detail later. Furthermore, the booklet producing apparatus 106 can also discharge the sheet S on which an image has been formed by the image forming apparatus 101 onto the upper discharge tray 125 or the lower discharge tray 137 without carrying out any processing.

[0031] (Buffer section) The buffer unit 120 will be described with reference to FIG. 4. FIG. 4 is an enlarged cross-sectional view of the buffer unit 120. The buffer unit 120 includes an inlet roller pair 121, a pre-buffer roller pair 122, a check valve 123, a reverse roller pair 124, and an inner discharge roller pair 126. The buffer unit 120 also includes an inlet sensor 127 for detecting a sheet, and a separation mechanism including a plunger solenoid 145 or the like for opening and closing (contacting and separating) the reverse roller pair 124. The inlet roller pair 121, the pre-buffer roller pair 122, the reverse roller pair 124, and the inner discharge roller pair 126 are roller pairs that sandwich and transport a sheet. The inlet roller pair 121 and the pre-buffer roller pair 122 are disposed in a transport path (inlet path) for the booklet production device 106 to receive the sheet S. The reversing roller pair 124 is disposed on a conveying path 139 (see FIG. 1) that communicates with the upper discharge tray 125. The inner discharge roller pair 126 is disposed on a conveying path (inner discharge path 166, see FIG. 1) that runs from the reversing roller pair 124 to the heating and pressurizing unit 167. The booklet making device 106 is provided with a discharge conveying path 138 (see FIG. 1) that runs from the heating and pressurizing unit 167 to the lower discharge tray 137. The entrance path is formed by the upper entrance guide 140 and the lower entrance guide 141. The first discharge path is formed by the upper reversing guide 142 and the lower reversing guide 143. The inner discharge path 166 is formed by the upper inner discharge guide 146 and the lower inner discharge guide 147. The entrance sensor 127 is disposed so as to detect the sheet received by the entrance roller pair 121. The entrance sensor 127 may be, for example, a reflective photosensor that irradiates the entrance path with infrared light through an opening provided in the upper entrance guide 140 and detects the reflected light from the sheet to determine the presence or absence of the sheet S. The lower entrance guide 141 may be provided with a hole larger than the spot diameter of the infrared light emitted by the entrance sensor 127 so as not to reflect the infrared light when no sheet is passing through the entrance path.

[0032] The check valve 123 is disposed downstream of the pre-buffer roller pair 122 in the sheet conveying direction in the entrance path. The check valve 123 is disposed rotatably about a rotation shaft 123a with respect to the inner discharge upper guide 146. The check valve 123 is movable between a first position that prevents the sheet from moving (backflowing) from the first discharge path to the entrance path and a second position that allows the sheet to move from the entrance path to the first discharge path. The check valve 123 is biased in the C2 direction from the second position toward the first position by a spring (not shown). The check valve 123 is configured to move in the C1 direction from the first position toward the second position by being pressed by the sheet, and to return to the first position when the sheet passes through. When viewed in the direction of the rotation axis of the check valve 123, the tip of the check valve 123 in the first position overlaps with the inversion upper guide 142. In addition, the tip of the check valve 123 is formed in a comb shape so as to enable overlap with the inverted upper guide 142. When viewed in the direction of the rotation axis of the check valve 123, a space is formed between the check valve 123 in the second position and the inverted upper guide 142, allowing the sheet to pass through.

[0033] The pair of reversing rollers 124 is composed of an upper reversing roller 124a and a lower reversing roller 124b, and a drive is supplied to both rollers. The upper reversing roller 124a and the lower reversing roller 124b are configured to rotate in sync at all times. A separation lever 144 is connected to the upper reversing roller 124a. The separation lever 144 is supported rotatably about a lever fulcrum shaft 144a with respect to the upper reversing guide 142. The separation lever 144 is rotatably connected to a plunger solenoid 145 at a solenoid connection shaft 144b. When a current flows through the plunger solenoid 145, the core moves in the direction D1 in the figure, and the separation lever 144 rotates in the direction E1 in the figure. In this case, the pair of reversing rollers 124 is in a separation state (a state in which the nip portion is opened) in which the upper reversing roller 124a and the lower reversing roller 124b are separated from each other. Furthermore, when the current flowing through the plunger solenoid 145 is stopped, the upper reversing roller 124a moves in the E2 direction and the core of the plunger solenoid 145 moves in the D2 direction due to the biasing force of the pressure spring 148. In this case, the pair of reversing rollers 124 is in a contact state (a state in which a nip portion is formed) in which the upper reversing roller 124a and the lower reversing roller 124b are in contact with each other.

[0034] (Buffer operation) Next, the operation of the buffer unit 120 will be described. FIG. 5(a) to FIG. 5(h) are diagrams showing the operation of the buffer unit 120. Hereinafter, it is assumed that the sheets are conveyed from the image forming apparatus 101 to the booklet production apparatus 106 in the order of sheet S1, sheet S2, and sheet S3. As described below, the buffer unit 120 performs an operation (hereinafter referred to as a buffer operation) of stacking a newly conveyed sheet on top of the sheet (stack) while moving the sheet (stack) back and forth between the reversing roller pair 124 and the inner discharge roller pair 126. In addition, the booklet production apparatus 106 accelerates the sheet conveying speed within the apparatus. Hereinafter, the sheet conveying speed by the inlet roller pair 121 is V1, and the sheet conveying speed (conveying speed after acceleration) by the pre-buffer roller pair 122, the reversing roller pair 124, and the inner discharge roller pair 126 is V2.

[0035] As shown in FIG. 5(a), when the trailing edge of the preceding sheet S1 passes through the inlet sensor 127, the conveying speed of the sheet S1 by the pre-buffer roller pair 122 and the reverse roller pair 124 is accelerated from V1 to V2. This widens the conveying interval between the sheet S1 and the following sheet S2, so that the reverse roller pair 124 can switch back the sheet S1 without the sheet S2 colliding with the sheet S1. As shown in FIG. 5(b), when the trailing edge of the sheet S1 passes through the check valve 123, the conveying by the reverse roller pair 124 is temporarily stopped. As shown in FIG. 5(c), the reverse roller pair 124 changes the rotation direction and conveys the sheet S1 toward the inner discharge roller pair 126. As shown in FIG. 5(d), the conveying of the sheet S1 by the reverse roller pair 124 and the inner discharge roller pair 126 is stopped at a position where the leading edge of the sheet S1 passes through the inner discharge roller pair 126 and is conveyed a predetermined amount. In addition, the upper inversion roller 124a moves in the direction E1 after the sheet S1 is sandwiched between the inner discharge roller pair 126. This causes the pair of inversion rollers 124 to separate, and the pair of inversion rollers 124 becomes ready to receive the succeeding sheet S2. After the upper inversion roller 124a separates, the succeeding sheet S2 is conveyed to the pair of inversion rollers 124. As shown in FIG. 5(e), when the trailing end of the succeeding sheet S2 passes the entrance sensor 127, the conveying speed of the sheet S2 is accelerated from V1 to V2, similar to the sheet S1. When the sheet S2 reaches a predetermined target position, the pair of inner discharge rollers 126 conveys the sheet S1 toward the pair of inversion rollers 124. When the speeds of the sheet S1 and the sheet S2 become substantially equal (the speed difference is substantially 0), the upper inversion roller 124a moves in the direction E2, and the pair of inversion rollers 124 come into contact with each other. When the pair of inversion rollers 124 comes into contact with each other, the pair of inversion rollers 124 simultaneously holds the sheets S1 and S2. Furthermore, the speed of the reversing roller pair 124 is adjusted so as to be equal to the conveying speed of the sheets S1 and S2 before switching from the separated state to the current state. As shown in Fig. 5(f), after the rear end of the sheet S2 passes through the check valve 123, the reversing roller pair 124 pauses again. Here, the target position is set so that the sheet S1 protrudes by a predetermined amount k from the sheet S2 in the conveying direction from the inner discharge roller pair 126 toward the alignment unit 156.In other words, among the stack of sheets stacked in the buffer unit 120, the sheet S1 on the lower side in the alignment unit 156 protrudes by a predetermined amount k downstream in the conveying direction toward the alignment unit 156 from the sheet S2 on the upper side in the alignment unit 156. As shown in FIG. 5(g), the pair of reversing rollers 124 changes its rotation direction and conveys the sheets S1 and S2 toward the pair of inner discharge rollers 126. The sheets S1 and S2 are conveyed toward the alignment unit 156 by the pair of inner discharge rollers 126. The upper reversing roller 124a moves in the direction E1 after the sheet S1 is sandwiched between the pair of inner discharge rollers 126. This causes the pair of reversing rollers 124 to separate, and the pair of reversing rollers 124 becomes ready to receive the succeeding sheet S3. As shown in FIG. 5(h), after the rear end of the sheet S2 passes through the pair of reversing rollers 124, the upper reversing roller 124a moves in the direction E2. This causes the pair of reversing rollers 124 to come into contact with each other and convey the sheet S3 while sandwiching it.

[0036] By repeating the above buffer operation, the buffer unit 120 can send sheets in a stacked state of a predetermined number of sheets to the alignment unit 156. Also, although the buffer operation for stacking two sheets has been described as an example here, it is possible to further stack sheet S3 on top of sheets S1 and S2 by temporarily stopping the conveyance of sheets S1 and S2 from the state of FIG. 5(g) and then conveying them in the opposite direction. In other words, the buffer unit 120 can create a sheet stack of three or more (e.g., five) sheets by repeating the operations of FIG. 5(d) to FIG. 5(g).

[0037] The target position for overlapping the sheets is determined based on the timing when the entrance sensor 127 detects the rear end of the sheet. Therefore, even if the length of the sheet in the conveying direction changes, the buffer operation of this embodiment allows the sheets to be overlapped with a predetermined amount of shift.

[0038] 1, the stack of sheets stacked in the buffer section 120 is transported from the inner discharge roller pair 126 through the intermediate transport roller pair 128 to the kick-out roller pair 129 from the input transport path 165. The sheet stack is then transported by the kick-out roller pair 129 to an alignment section 156 (intermediate stacking section, processing stage) consisting of an intermediate upper guide 151, an intermediate lower guide 152, etc. In addition, downstream of the kick-out roller pair 129, a bundle holding flag 150 is disposed to suppress lifting of the trailing end of the stacked sheets so that the trailing end of the sheets already stacked in the alignment section 156 does not interfere with the leading end of the succeeding sheet transported to the alignment section 156.

[0039] (Consistent part configuration) Next, the configuration of the alignment section 156 will be described with reference to FIGS. 6 and 7. FIG. 6 is a cross-sectional view of the alignment section 156. FIG. 7 is an exploded view showing the components of the movable unit 159. In the following description and in each drawing, the direction in which the pressure member of the heat and pressure unit 167 moves relative to the receiving member 180 to pressurize the sheet stack is defined as the Z direction. The Z direction is the height direction (thickness direction) of the sheet stack stacked on the alignment section 156. In addition, the directions perpendicular to each other in a virtual plane perpendicular to the Z direction are defined as the X direction and the Y direction. As necessary, the directions of the arrows X, Y, and Z shown in each drawing are respectively represented as the +X side, the +Y side, and the +Z side, and the opposite sides are respectively represented as the -X side, the -Y side, and the -Z side. In this embodiment, the Y direction is substantially parallel to the conveying direction in which the sheet is conveyed to the alignment section 156 by the kick-out roller pair 129. In addition, in this embodiment, the X direction is the sheet width direction perpendicular to the conveying direction. In the following description, the Y direction may be referred to as the “vertical direction”, and the X direction may be referred to as the “width direction” or “horizontal direction”. The alignment portion 156 includes an intermediate lower guide 152 as a stacking portion that supports the sheet stack, an intermediate upper guide 151 facing the intermediate lower guide 152, and a movable unit 159 including a vertical alignment plate 154 and a vertical alignment roller 153.

[0040] As shown in FIG. 7, the vertical alignment plate 154 has a plurality of sheet contact portions 154a, 154b, and 154c arranged side by side in the sheet width direction. The sheet contact portions 154a, 154b, and 154c are reference positions for sheet alignment in the sheet conveying direction (Y direction). The vertical alignment roller 153 is rotatably held by a roller holder 160. The roller holder 160 can be swung by a driving force of a solenoid 163. By the swinging of the roller holder 160, the vertical alignment roller 153 can be moved between a position where it contacts the sheet S on the intermediate lower guide 152 and conveys the sheet, and a position where it is retracted upward from the sheet S. In addition, a drive motor 161 is attached to the movable unit 159. The drive force of the drive motor 161 is transmitted via a gear train 162, so that the vertical alignment roller 153 rotates. The movable unit 159 is movable as an integral unit in the sheet conveying direction (Y direction) relative to the intermediate lower guide 152. As shown in FIG. 6, the alignment section 156 includes a width alignment member 155, a drive motor 158, and width alignment plates 172a and 172b (FIG. 8(a)). The width alignment member 155 is movable in the sheet width direction (X direction) by the driving force of the drive motor 158. The width alignment member 155 includes a plurality of sheet pressure members 155a, 155b, and 155c arranged side by side in the sheet conveying direction. As shown in FIG. 8(a), the width alignment plates 172a and 172b are composed of a plurality of plate-shaped members (sheet abutment parts) arranged side by side in the sheet conveying direction. The width alignment plates 172a and 172b are reference positions for sheet alignment in the sheet width direction (X direction).

[0041] (matching part operation) The operation of the alignment unit 156 will be described with reference to Figs. 8(a) to 8(d). Figs. 8(a) to 8(d) are schematic diagrams of the alignment unit 156 as viewed from above in the Z direction. The illustration of the intermediate upper guide 151 and the driving components of the heating and pressing unit 167 are omitted. When aligning a sheet stack in the alignment unit 156, the movable unit 159 is positioned in advance at a predetermined standby position in the sheet conveying direction (Y direction) according to the sheet size. The standby position is a position where the distance in the Y direction from the nip position of the kick-out roller pair 129 to the sheet contact parts 154a to 154c of the vertical alignment plate 154 is slightly longer than the length of the sheet. The operation of the alignment unit 156 will be described below based on an example in which a sheet stack consisting of five sheets S1 to S5 stacked in the buffer unit 120 is conveyed. The number of sheets stacked in the buffer unit 120 can be changed arbitrarily and is not limited to five.

[0042] FIG. 8(a) shows a state where the first sheet S1 and the second sheet S2 are being conveyed toward the alignment section 156. The movable unit 159 (the vertical alignment plate 154 and the vertical alignment roller 153) has completed moving to a standby position according to the sheet size. The width alignment member 155 is on standby at a position slightly outwardly spaced from the side end position of the sheet stack so as not to interfere with the conveyance of the sheet stack. FIG. 8(b) shows a state where the trailing end of the first sheet S1 has passed through the nip of the kick-out roller pair 129, and the leading end of the sheet S1 has reached the vertical alignment roller 153. The vertical alignment roller 153 has been lowered to the abutment position in advance by energizing the solenoid 163, and is rotated by the drive motor 161. The sheet S1 is conveyed to the +Y side by the vertical alignment roller 153 and is abutted against the vertical alignment plate 154, so that it is aligned in the sheet conveyance direction. After that, each time the succeeding sheets S2 to S5 leave the kick-out roller pair 129, each sheet is conveyed to the +Y side by the vertical alignment roller 153 and abuts against the vertical alignment plate 154, so that the sheet is aligned in the sheet conveying direction. FIG. 8(c) shows a state in which the five sheets S1 to S5 are abutted against the vertical alignment plate 154, and the alignment in the sheet conveying direction is completed. In this state, the width alignment member 155 is moved in the sheet width direction (X direction) by the driving force of the drive motor 158 (FIG. 6). The sheets S1 to S5 are moved toward the width alignment plates 172a and 172b by one side edge being pressed by the sheet pressure parts 155a, 155b, and 155c of the width alignment member 155. FIG. 8(d) shows a state in which the side edges of the sheets S1 to S5 are abutted against the width alignment plates 172a and 172b, respectively. As a result, the sheets S1 to S5 are aligned in the sheet width direction. Thereafter, the sheets on which the adhesive layers are formed are thermocompression-bonded in a stacked state by the heating and pressing unit 167 described later. In this embodiment, five sheets S1 to S5 are thermocompression-bonded. When a booklet consisting of six or more sheets is to be produced, the alignment section 156 prepares to receive the sixth and subsequent sheets in parallel with the thermocompression-bonding of the sheets S1 to S5. Specifically, the width alignment member 155 is moved in the retracting direction (-X side). FIG. 8(e) shows the paper position after XY alignment when the sheet S is A4 size, and FIG. 8(f) shows the paper position after XY alignment when the sheet S is A5 size.In this embodiment, Y alignment is performed so that one edge of the sheet S is aligned with the vertical alignment reference position G of the heating and pressurizing unit 167 (one-side reference). Here, the heating and pressurizing unit 167 is a device that performs long-side binding on the sheet edge in the vertical direction, and the maximum sheet width (Sa) that the heating and pressurizing unit 167 can handle is 297 mm, which corresponds to A4 size (297 mm long x 210 mm wide). Also, the minimum sheet width (Sb) that the heating and pressurizing unit 167 can handle is 210 mm, which corresponds to A5 size (210 mm long x 149 mm wide).

[0043] (heating and pressurizing unit) The configuration of the heating and pressurizing unit 167 according to this embodiment will be described with reference to FIG. 9. FIG. 9 is a perspective view of the heating and pressurizing unit 167. The heating and pressurizing unit 167 is an example of a sheet bonding device (bonding unit, bonding means, thermocompression means, lamination processing section) that bonds sheets together. As shown in FIG. 9, the heating and pressurizing unit 167 includes a heater section 171 as a heating and pressurizing means including a pressure plate 169, a receiving member 180 that faces the pressure plate 169 and receives the pressure force of the heater section, and a drive system including a motor 177. The receiving member 180 includes a receiving plate 181 formed of an elastic material, a receiving plate support 182 made of a heat-resistant resin member that supports the receiving plate 181, and a highly rigid metal receiving side frame 183 that further supports the receiving plate support 182. A silicone rubber sheet is used as the material for the receiving plate 181, and the plate thickness is 3 mm (thickness in the Z direction) and the rubber hardness is 70° (ISO7619 standard). In this embodiment, silicone rubber having heat resistance and appropriate elasticity is used, but this is not limiting and a material according to the required heat resistance, elasticity, and pressure resistance may be used. The heater section 171 has a pressure plate 169, a ceramic heater (heating body) 168 (FIG. 10), and a metal stay 170. The pressure plate 169 is an example of a pressure member that applies pressure to the sheet stack to be bonded. The pressure plate 169 is a plate-like shape that is elongated in the Y direction and has a thickness direction in the Z direction. The pressure plate 169 is made of aluminum material (A6063 material). The pressure plate 169 is basically configured with a thickness of 0.8 mm. The length of the pressure plate 169 in the Y direction is 300 mm. The Young's modulus of the aluminum material used for the pressure plate 169 here is 68 GPa, and the thermal conductivity λp The thermal conductivity was 237 W / mK. By using a highly thermally conductive material such as aluminum (A6063 material) for the pressure plate 169, it becomes easy to transfer the heat of the ceramic heater 168 to the sheet. The ceramic heater 168 is an example of a heating means for heating the pressure member. The ceramic heater 168 is a heater substrate in which a pattern of a heating resistor is formed on a ceramic substrate. The ceramic heater 168 is arranged so as to be in contact with the pressure plate 169. The dimensions of the ceramic heater 168 are a thickness of 1.0 mm, a width of 8.0 mm, and a length of 350 mm, and the thermal conductivity λ h The thermal conductivity λ was 22 W / mK. Here, the thermal conductivity λ was measured by a thermal conductivity measuring device (ai-Phase Mobile2, Ai-Phase Co., Ltd.). The Young's modulus of the ceramic heater 168 was 370 GPa. The heater support 603 is a member for supporting the ceramic heater 168, and is fixed to the pressure plate 169 and the metal stay 170 having rigidity. Here, the metal stay is made of iron with a thickness of 1.8 mm, and is further strengthened by bending it into a U-shape. A lift plate 172 is fixed to the metal stay 170 of the heater part 171. The contact parts between the lift plate 172 and the metal stay 170 are 172g and 172h, and the lift plate 172 moves integrally with the heater part 171. In this embodiment, the width adjustment plates 172a and 172b are formed integrally with the lift plate 172 by bending a part of the sheet metal member constituting the lift plate 172. In addition, since the lift plate 172 has a slight gap (172i, 172j) with respect to the guide shaft 173, when the pressure plate 169 contacts the sheet stack, it can swing in the Y direction as shown by the dotted line M, and can move to somewhat follow the sheet surface. Therefore, even if the sheet surface is slightly inclined or a moment force is applied, good pressure can be applied.

[0044] The heating and pressurizing unit 167 can use a pressure plate 169 extending in the Y direction to thermocompress the sheet stack loaded on the alignment section 156 along one side extending in the Y direction. The alignment section 156 and the heating and pressurizing unit 167 of this embodiment can align A4 size or other sheets in an orientation in which the long side is parallel to the sheet conveying direction (long side feed orientation) and thermocompress the sheets in an adhesive region (FIG. 2(a)) along the long side, thereby performing so-called long side binding.

[0045] The drive system (pressure mechanism) of the heating and pressing unit 167 includes a motor 177 as a drive source, a gear train 178, a pinion gear 179, and a rack gear 175. The gear train 178, the pinion gear 179, and the rack gear 175 are an example of a drive transmission mechanism that converts the rotation of the motor 177 into the moving direction (Z direction) of the heater unit 171 and transmits it to the heater unit 171. The pinion gear 179 is connected to the motor 177 via the gear train 178. The pinion gear 179 meshes with the rack gear 175. The gear train 178, the pinion gear 179, and the rack gear 175 configure a speed reduction mechanism for obtaining a pressure force required for thermocompression bonding of the sheet stack. For example, a worm gear or a planetary gear mechanism may be used as the speed reduction mechanism. The rack gear 175 is guided by a cylindrical guide shaft 173 extending in the Z direction and reciprocates in the Z direction. The guide shaft 173 is fixed to the frame of the heating and pressurizing unit 167. A compression spring 174 that generates a force for pressing the pressurizing plate 169 against the sheet is disposed between the rack gear 175 and the lower surface 172c of the lift plate 172. When the heater portion 171 is separated in the Z direction, the rack gear 175 is abutted against the upper surface 172d of the lift plate 172 by the compression spring 174.

[0046] The photointerrupter 176 is held integrally with the rack gear 175 and detects a change in the relative position between the rack gear 175 and the lift plate 172. The motor 177 is used to raise and lower the heater portion 171. A pinion gear 179 is engaged with the rack gear 175 via a gear train 178 from a motor gear (not shown), and the rotation of the motor 177 is transmitted to the rack gear 175. When the heating and pressing unit 167 performs thermocompression bonding of a sheet stack, the rack gear 175 moves in the pressing direction (-Z side) due to the driving force transmitted from the motor 177. This causes the lift plate 172 and the heater portion 171 to move in the pressing direction (-Z side), and the pressing plate 169 comes into contact with the sheet stack. After pressing the sheet stack S, the heater portion 171 moves away. The pressing force K1 from the lift plate contact portion 172g to the metal stay 170 is set to 15 kgf. The pressure K2 applied from the lift plate contact portion 172h to the metal stay 170 was set to 15 kgf. That is, the total pressure applied to the sheet stack by the heating and pressing unit 167 was 30 kgf.

[0047] As shown in FIG. 10(a), the pressure plate 169 has a cross-sectional shape in which the center in the X direction protrudes in the pressure direction (-Z side) and extends in the Y direction. The tip of the contact part 169a that contacts the upper surface of the sheet stack has a curved shape with a diameter of 2.5 mm in order to concentrate the pressure force of the heating and pressing unit 167 and increase the surface pressure when pressing the booklet, and corresponds to the pressure center position (X1-X1' cross section) of the heating and pressing unit 167. The receiving plate support 182 has 182a as a sheet guide part for conveying the sheet to the heating and pressing unit 167, and a receiving plate support part 182b that supports the receiving plate 181 and receives the pressure force of the heater part. Here, the receiving plate support part 182b has a function of adjusting the longitudinal pressure force distribution at the pressure center position (X1-X1' cross section) of the heater part 171, and details will be described later. The receiving side frame 183 is flat on the contact surface with the receiving plate support 182. In this embodiment, the material of the receiving plate support 182 is a PPS material (polyphenylene sulfide material) having heat resistance. The heater unit 171 has a temperature detection means TH (not shown) for detecting the temperature of the ceramic heater 168. In this embodiment, a resistor having NTC characteristics (Negative Temperature Coefficient) is used as the temperature detection means TH, but this is not limited to this, and a resistor having PTC characteristics (Positive Negative Temperature Coefficient), various thermocouples, and radiation thermometers may also be used. The temperature detection means TH is disposed at a position 149 mm from the vertical alignment reference position G as the sheet reference position, corresponding to the center of the long side of the A4 size in the heating and pressing unit 167. The control unit of the booklet production device 106 can control the temperature by a power application means (not shown) so that the detection temperature of the temperature detection means TH becomes the set temperature (220°C). By setting the set temperature to 220°C, it is possible to make the toner temperature at the time of bonding the maximum number of five sheets at once to be equal to or higher than the reference temperature of 80°C.

[0048] (Operation of the heating and pressurizing unit) The thermocompression operation of the heating and pressurizing unit 167 will be described with reference to Figs. 10(a) to 10(f). Each of Figs. 10(a) to 10(f) is a view of the heating and pressurizing unit 167 as seen in the sheet conveying direction (Y direction). Fig. 10(a) shows the same state as Fig. 8(c), that is, a state in which alignment of the sheets S1 to S5 in the sheet conveying direction (Y direction) has been completed. In this state, the heater section 171 is located at a position separated from the sheet stack in the Z direction. Fig. 10(b) shows the same state as Fig. 8(d), that is, a state in which alignment of the sheets S1 to S5 in the width direction has been completed. The sheets S1 to S5 are aligned in the sheet width direction (X direction) by being abutted against width alignment plates 172a and 172b. FIG. 10(c) shows a state where the heater unit 171 moves in the pressure direction (-Z side) due to the forward rotation of the motor 177, and the contact unit 169a of the pressure plate 169 abuts against the uppermost sheet S5. FIG. 10(d) shows a state where the sheets S1 to S5 are sandwiched between the pressure plate 169 and the receiving member 180 as the motor 177 continues to be driven, and the sheets S1 to S5 are being thermocompressed. The compression spring 174 is pressed against the lower surface of the rack gear 175 and contracts, and the repulsive force of the compression spring 174 increases. The repulsive force of the compression spring 174 presses the sheets S1 to S5 against the pressure plate 169 with a total pressure of 30 kgf via the lift plate 172 and the heater unit 171. In this embodiment, the pressing time is set to 3.0 seconds. The motor 177 is controlled so as to generate a predetermined pressure by stopping at a predetermined rotation amount after the photointerrupter 176 is shielded by the rib 172e of the lift plate 172. FIG. 10(d) shows the state in which the next sheets S6-S10 are conveyed to the alignment section 156 in parallel with the thermocompression bonding of the sheets S1-S5. FIG. 10(e) shows the state in which the heater section 171 moves (retracts) to the opposite side of the pressure direction (+Z side) due to the reverse rotation of the motor 177 after the thermocompression bonding of the sheets S1-S5 is completed, and the pressure plate 169 is separated from the sheet S5. FIG. 10(e) shows the state in which the next sheets S6-S10 are aligned, and the sheets S1-S5 are abutted against the width alignment plates 172a and 172b after the heater section 171 is retracted.FIG. 10(f) shows a state in which the heater unit 171 moves again in the pressure direction (-Z side) by the forward rotation of the motor 177, the sheets S1 to S10 are sandwiched between the pressure plate 169 and the receiving member 180, and the sheets S6 to S10 are being thermocompressed. The motor 177 is controlled so that a predetermined pressure force is generated by stopping at a predetermined rotation amount after the photointerrupter 176 is shielded by the rib 172e of the lift plate 172. This makes it possible to make the operating length of the compression spring 174 the same when the sheets S1 to S5 are thermocompressed in FIG. 10(d) and when the sheets S6 to S10 are thermocompressed in FIG. 10(f). In other words, even if the thickness of the sheets S aligned with the heating and pressing unit 167 changes, the pressure force for pressing the sheet stack can be kept constant and thermocompressed. Also, by forming an adhesive toner image on the upper surface of sheet S5 and / or the lower surface of sheet S6, the sheet bundle consisting of sheets S1 to S5 and the sheet bundle consisting of sheets S6 to S10 are thermocompression-bonded together. In this way, the heating and pressing unit 167 performs one thermocompression-bonding operation every time a predetermined number of sheets of a sheet bundle are aligned by the alignment section 156, so that a booklet consisting of a greater number of sheets than the predetermined number can be created. Here, an example in which a booklet consisting of 10 sheets S1 to S10 is created has been described, but a booklet consisting of several tens of sheets or more can also be created. Also, although a sequence in which the thermocompression operation is performed for every predetermined number of sheets has been described, the thermocompression operation may be performed for every number of sheets, such as first thermocompressing two sheets and then thermocompressing one sheet at a time.

[0049] Next, in order to confirm the function and effect of this embodiment, a comparative verification is performed between this embodiment, Comparative Example 1, and Comparative Example 2. The comparative verification was performed on the pressure distribution of each heating and pressing unit 167 and the booklet adhesive strength. Here, in this embodiment, the shape of the receiving plate support part of the heating and pressing unit 167 is appropriately adjusted compared to Comparative Example 1 and Comparative Example 2, thereby adjusting the balance of the pressure distribution and ensuring good booklet adhesive strength. FIG. 11(a) is a schematic diagram of the X1-X1' cross section when five sheets of A4 size paper and twenty sheets of A5 size paper are pressed by the heating and pressing unit 167 of this embodiment. In this embodiment, the pressure center Fc of the pressure forces K1 and K2 applied from the contact parts 172g and 172h of the lift plate 172 in FIG. 10 is the same as the center position Yc in the Y direction of the heating and pressing unit 167. Here, the distance from the longitudinal alignment reference position G of the sheet on one end side to the pressure center position of the pressure force K1 is L. K1 (75mm), the distance from the vertical alignment reference position G to the pressure center position of the pressure force K2 is L K2 The distance to the center of pressure Fc by the pressure force K1 and the pressure force K2 is L Fc (150 mm), which is the center position Yc (distance L Yc150 mm). That is, when pressing the sheet stack, the pressure forces K1 and K2 are applied to positions symmetrically with respect to the center position Yc in the Y direction of the heating and pressing unit 167. The longitudinal width of the heating and pressing unit 167 in this embodiment is adjusted to the A4 size, which is the maximum sheet width. Therefore, when pressing A4 size paper, most of the pressing part of the heating and pressing unit 167 becomes the sheet width Sa of the A4 size paper, so that stable pressing in the Z direction is possible. On the other hand, when pressing A5 size paper, which is the minimum sheet width, if the number of sheets in the booklet increases (A5-20 sheets in the figure), a non-pressurized area Sc will be generated in addition to the area where the A5 size paper is pressed. Specifically, the non-pressurized area Sc is a third area inside the first area (A4(Sa) in FIG. 11(b)) where the heating and pressurizing unit 167 presses A4 size paper and outside the second area (A5(Sb) in FIG. 11(b)) where the heating and pressurizing unit 167 presses A5 size paper. At this time, a rotational moment M1 is applied to the heating and pressurizing unit 167 about the guide shaft 173 (FIG. 9), causing a slight difference in pressure between the left and right sides within the A5 sheet width Sb.

[0050] 11B shows the thickness of the receiving plate support portion 182b when no pressure is applied in the X1-X1' cross section shown in FIG. 10. Here, the thickness H in the Z direction (sheet pressure direction) at the end Y2 point of the sheet width Sb of A5 size paper is Y2 The thickness H at the Y1 point, which corresponds to the vertical alignment reference position G, is the thinnest. Y1 and the thickness H at the end Y3 of the sheet width Sa of A4 size paper Y3 is H Y2 It is thicker than (H Y1 >H Y2 , H Y3 >H Y2 In this embodiment, H Y1 is 2.5mm, H Y2 is 2.3mm, H Y3 The thickness is set at 2.6 mm. Y1 ~H Y2 The gradient between, and H Y2 ~H Y3 The gradient between the two creates a smooth curved surface. Y1~H Y2 The gradient between (H Y1 >H Y2 ) can increase the pressure on the Y1 side and decrease the pressure on the Y2 side. Therefore, when pressing A5 size paper, it is effective in suppressing the concentration of pressure on the Y2 side caused by the rotation moment M1. Y2 ~H Y3 The gradient between (H Y3 >H Y2 ) is effective only when pressing A4 size paper, and the pressurized H Y1 ~H Y2 The gradient between (H Y1 >H Y2 ) and can have a balancing effect.

[0051] FIG. 11(c) shows the pressure distribution in the Y direction when five sheets of A4 size paper and twenty sheets of A5 size paper are pressed using the heating and pressing unit 167 of this embodiment. The pressure distribution is measured by sandwiching a pressure measurement film "Prescale (product name)" manufactured by Fujifilm Corporation when the heating and pressing unit 167 is pressed. This causes the pressure measurement film to turn red according to the applied pressure, making it possible to visualize the surface pressure distribution. When the paper stack between the heating and pressing units 167 becomes thinner, the cushioning effect of the paper stack, such as an elastic body, is weakened. As a result, the paper stack becomes more susceptible to the left-right difference in pressure force due to the shape of the pressing means, pressing member, and receiving member of the heating and pressing unit 167. In order to suppress this left-right difference, five sheets of A4 size paper are used in this embodiment, but two sheets may be used for evaluation as a more severe experimental condition. On the other hand, the reason for using 20 sheets of A5 size paper is that the thicker the paper stack is, the greater the rotational moment M1 acts, making it easier for left-right differences to occur in the longitudinal pressure distribution, and the H of this embodiment Y1 ~H Y2This is because it is easy to confirm the effect of the constant pressure action due to the gradient between the two. The pressure distribution in FIG. 11(c) is the result of quantifying the colored film using a standard density conversion table. In FIG. 11(c), Gtgt is the reference surface pressure (0.4 MPa) required to ensure adhesive strength by the heating and pressing unit 167 of this embodiment. In the pressure distribution of A5 size paper, although the surface pressure has a gradient from Y1 to Y2 in the Y direction due to the influence of the rotation moment M1, the minimum value of the surface pressure GBmin exceeds the reference surface pressure Gtgt. In addition, in the pressure distribution of A4 size paper, a generally uniform pressure distribution can be formed from Y1 to Y3 in the Y direction with almost no influence of the rotation moment. In addition, although the minimum value GAmin of the pressure applied to the sheet occurs in the region Y2 to Y3 near Y2 (in the third region or at the end position of the second region adjacent to the third region), it is possible to exceed the reference surface pressure Gtgt. This is the result of being able to properly adjust the pressure distribution in the Y direction for different sheet sizes by properly adjusting the thickness of the receiving plate support portion 182b, taking into consideration the effects of the rotation moment and bending of the heating and pressurizing unit 167. In this embodiment, by properly adjusting the thickness of the receiving plate support portion 182b of the receiving plate support 182, it is possible to suppress bias in the pressure distribution when pressing A5 size paper, while maintaining a good pressure distribution for A4 size paper. Y3 >H Y2 As a result, a pressure greater than the minimum value GAmin exists to the right of the minimum value GAmin in FIG. 11(c).

[0052] 12(a) is a schematic diagram of the X1-X1' cross section when five sheets of A4 size paper and twenty sheets of A5 size paper are pressed using the heating and pressing unit 167 as Comparative Example 1 of this embodiment. Here, in Comparative Example 1, the thickness of the receiving plate support portion 182b is uniform in the Y direction in the X1-X1' cross section (H Y1 =H Y2 =H Y3= 2.5 mm, see FIG. 12(b). Here, the pressure positions of the pressure forces K1 and K2 are the same as in this embodiment. Therefore, when A5 size paper is pressed, the rotation moment M1 with the guide shaft 173 (FIG. 9) as the fulcrum acts in the same way as in this embodiment. As a result, as shown in FIG. 12(c), the pressure distribution in the longitudinal direction has a large difference between the left and right pressure forces within the range of the A5 width Sb. Also, while the pressure force on the Y2 side is high, the pressure force GBmin on the Y1 side is low and falls below the reference surface pressure Gtgt. On the other hand, the pressure distribution on the A4 size paper is uniform and exceeds the reference surface pressure Gtgt.

[0053] 13A is a schematic diagram of the X1-X1' cross section when five sheets of A4 size paper and twenty sheets of A5 size paper are pressed using the heating and pressing unit 167 as Comparative Example 2 of this embodiment. In Comparative Example 2, the thickness of the receiving plate support portion 182b is a thickness H at the Y1 point corresponding to the vertical alignment reference position G at both ends of the sheet width Sb of the A5 size paper in the X1-X1' cross section. Y1 is the thickness H at point Y2 Y2 It is thicker than (H Y1 >H Y2 ) On the other hand, the thickness H at point Y2 Y2 is the thickness H at point Y3 Y3 The same relationship was established as (H Y2 =H Y3 ). Also H Y1 ~H Y2 The gradient between the two surfaces is smoothly curved. Y1 ~H Y2 The gradient between (H Y1 >H Y2 ) can increase the pressure on the Y1 side and decrease the pressure on the Y2 side, so that the concentration of pressure on the Y2 side caused by the rotation moment M1 when pressing A5 size paper can be suppressed. Y2 ~H Y3 There is no gradient between them (H Y2 =H Y3 ) so when pressing A4 size paper, H Y1 ~H Y2 The gradient between (H Y1 >H Y2), which results in a difference in pressure between the left and right. As a result, in the pressure distribution of A5 in FIG. 13(c), within the range of the A5 sheet width Sb, the surface pressure has a gradient from Y1 to Y2 in the Y direction due to the influence of the rotation moment M1 as in this embodiment, but the minimum surface pressure GBmin exceeds the reference surface pressure Gtgt. On the other hand, in the pressure distribution of A4, within the range of the A4 sheet width Sa, the gradient of the thickness of the backing plate support portion 182b (H Y1 >H Y2 ) causes a difference in the pressure distribution between the left and right, with the pressure on the Y1 side being higher and the pressure on the Y3 side being lower. As a result, the minimum pressure GAmin applied to the sheet falls below the reference surface pressure Gtgt on the Y3 side.

[0054] Here, in order to verify the effect of this embodiment, booklets according to this embodiment, Comparative Example 1, and Comparative Example 2 were produced, and the adhesive strength of the adhesive portion was compared. First, a booklet quality test method for booklet adhesive strength will be described. First, a booklet is produced by the image forming apparatus 101 and the heating and pressurizing unit 167. At this time, in each test condition, a booklet of 5 sheets was produced in the case of an A4 size booklet, and a booklet of 20 sheets was produced in the case of an A5 size booklet. Here, the adhesive treatment of the paper bundle by the heating and pressurizing unit 167 is performed in groups of 5 sheets. In this booklet adhesive strength test, an A4 size GF-C081 manufactured by Canon Inc. was used as the sheet S. In the experiment with the sheet size of A5, the A4 size GF-C081 was cut in half and used to eliminate the influence of factors other than the sheet size, and the comparison was performed. Next, a method for producing a test piece for performing a quality test of booklet adhesive strength from the produced booklet will be described. Figure 14(a) shows A4 size paper, and Figure 14(b) shows A5 size paper, and test piece E or test piece F is created from two booklets of each size. In the case of A4 size, S3 to S5, which correspond to the 3rd to 5th pages, are peeled off and removed from the booklet of the five-sheet stack created, leaving two booklets with only S1 and S2 glued together. In the case of A5 size, S1 to S18, which correspond to the 1st to 18th pages, are peeled off and removed from the booklet of the 20-sheet stack created, leaving two booklets with only S19 and S20 glued together. After that, in the case of A4 size paper, A4 size paper test piece E including the glued part D was created by cutting it to a dimension of 20 mm in width (W) and 50 mm in length (L) as shown in Figure 14(a). At this time, test pieces E are created from E1 to E14 in order from the vertical alignment reference position G. Similarly, in the case of A5 size paper, a test piece F of A5 size paper including adhesive part D was created by cutting it to have dimensions of width (W) 20 mm and length (L) 50 mm as shown in Figure 14(b). At this time, test pieces F were created from F1 to F10 in order from the vertical alignment reference position G. Next, as shown in Figure 14(c), one of the test pieces E or F was held by an upper holding member and the other was held by a lower holding member. The upper holding member was further connected to a digital force gauge M (Nidec-Shimpo Corporation, FGP-2).After that, the digital force gauge was gradually raised upward, and the peeling force when the adhesive part D peeled off was measured by the digital force gauge, and the peak value of the peeling force was recorded. The measurements were performed five times for each adhesive part, and the average value was taken as the booklet adhesive strength of the adhesive part D. The authors confirmed that the adhesive strength of the booklet is practically desirable to be 1.0 N / cm or more per unit distance in the width direction of the test piece, so the quality standard was determined to be 1.0 N / cm or more as the booklet strength OK, and if it was less than that, the booklet strength was determined to be NG. The reason why the adhesive strength between S1 and S2 was measured for A4 size paper is that the booklet is thin and is easily affected by the adhesive strength due to the pressure distribution of the heating and pressing unit 167 at the part close to the receiving plate 181. The reason why the adhesive strength between S19 and S20 was measured for A5 size paper is that the booklet becomes thick to a certain extent, and the heating and pressing unit 167 is easily affected by the rotation moment.

[0055] FIG. 15 shows the results of the booklet adhesive strength test in this embodiment, Comparative Example 1, and Comparative Example 2. FIG. 15(a) shows the booklet adhesive strength in this embodiment, and it can be seen that the adhesive strength exceeds the standard adhesive strength of 1.0 N / cm at each adhesive portion for both A4 size paper (E1 to E14) and A5 size paper (F1 to F10), and sufficient adhesive strength is obtained. In detail, although the A5 size paper is affected by the rotation moment M1, the standard adhesive strength of 1.0 N / cm can be exceeded even at F1 and F2 on the vertical alignment reference position G side by appropriately forming the thickness of the receiving plate support portion 182b. Also, for A4 size paper, the thickness of the receiving plate support portion 182b can be appropriately formed, so that the standard adhesive strength of 1.0 N / cm can be exceeded even at E9 to E11 where the thickness of the receiving plate support portion 182b is thin. FIG. 15(b) shows the booklet adhesive strength in Comparative Example 1. For A4 size paper, good adhesive strength is obtained at E1 to E14, but for A5 size paper, the standard adhesive strength of 1.0 N / cm cannot be reached at F1 and F2 on the side of the vertical alignment reference position G. This is thought to be due to the influence of the difference in pressure distribution between the left and right sides caused by the rotation moment M1 of the heating and pressing unit 167. At the end on the side of the vertical alignment reference position G corresponding to F1 and F2, the pressure does not reach the standard surface pressure Gtgt, so the pressure is insufficient and the adhesion between the papers is not sufficient. As a result, F1 and F2 do not reach the standard adhesive strength. FIG. 15(c) shows the booklet adhesive strength in Comparative Example 2. For A5 size paper, it exceeds the standard adhesive strength of 1.0 N / cm as in this embodiment, and it can be seen that sufficient adhesive strength is obtained. In detail, when A5 size paper is pressed, although it is affected by the rotation moment M1, by varying the thickness of the backing plate support portion 182b only in the area pressed by the A5 sheet, it is possible to exceed the standard adhesive strength of 1.0 N / cm even at F1 and F2 on the side of the vertical alignment reference position G. On the other hand, for A4 size paper, the adhesive strength falls below the standard adhesive strength of 1.0 N / cm at E12 to E14 on the non-reference side. This is due to the gradient (H Y1 >H Y2) causes a difference in the distribution of pressure between the left and right sides, resulting in a higher pressure on the Y1 side and a lower pressure on the Y3 side.

[0056] Table 1 shows a list of comparative verification results between this embodiment, Comparative Example 1, and Comparative Example 2. The (M) measurement results of pressure distribution and (N) measurement results of booklet adhesive strength shown in Table 1 are a summary of the contents and verification results described above using Figures 11 to 13 and 15. Table 1 will be explained below.

[0057] [Table 1]

[0058] (L) Shape of the receiving plate support part In this embodiment, the thickness (H Y1 , H Y2 , H Y3 ) (Fig. 11(b)). Here, the thickness at point Y1, which corresponds to the vertical alignment reference position G, is H Y1 , the thickness corresponding to the end point on the non-reference side of the sheet width Sb of A5 size paper is H Y2 , the thickness corresponding to the end point on the non-reference side of the sheet width Sa of A4 size paper is H Y3 The shape of the receiving plate support part in this embodiment (L-J1) is the end H of the pressure area for A5 size paper. Y2 The gradient is set on both sides of the Y direction starting from H Y1 >H Y2 , H Y3 >H Y2 On the other hand, in the shape (L-H1) of the receiving plate support portion of Comparative Example 1, the receiving plate support portion 182b has a configuration that does not have a gradient due to the thickness (H Y1 =H Y2 =H Y3 Furthermore, in the shape of the receiving plate support part of Comparative Example 2 (L-H2), the edge H of the pressure region of the A5 size paper Y2 The gradient is set to one side (reference side) in the Y direction starting from H Y1 >H Y2 , H Y2 =H Y3).

[0059] (M) Pressure distribution of the heating and pressurizing unit In this embodiment, the applied pressure can be maintained at or above the reference value (0.4 MPa) for both A4 size paper and A5 size paper (M-J1-1, M-J1-2). On the other hand, in Comparative Example 1 and Comparative Example 2, there are some places where the applied pressure falls below the reference value (0.4 MPa) (M-H1-2, M-H2-1).

[0060] (N) Booklet adhesive strength In this embodiment, the booklet adhesive strength can be made equal to or greater than the standard value (1.0 N / cm) for both A4 size paper and A5 size paper (N-J1-1, N-J1-2). On the other hand, in Comparative Example 1 and Comparative Example 2, there are some places where the booklet adhesive strength cannot be made equal to or greater than the standard value (1.0 N / cm) (N-H1-2, N-H2-1).

[0061] As described above, in the heating and pressurizing unit 167 that can accommodate a plurality of sheet sizes, by appropriately adjusting the thickness of the receiving plate support portion 182b, it is possible to reduce the difference between the left and right pressure distributions without using a complicated mechanism that operates separately for each sheet size. As a result, it is possible to achieve good adhesive strength without increasing the size of the device or significantly increasing costs. In addition, in this embodiment, the pressure distribution of the heating and pressurizing unit 167 is realized by changing the thickness of the receiving plate support portion 182b in the Y direction, but this is not the only possible case. For example, it may be realized by changing the thickness in the Y direction of the receiving plate 181. It may also be realized by changing the thickness in the Y direction of the pressure plate 169, which is a part of the heating and pressurizing unit 167.

[0062] In this embodiment, a configuration has been described in which the heating and pressurizing unit 167 can swing around a guide shaft that can be raised and lowered. However, even in a configuration in which the heating and pressurizing unit 167 cannot swing, the pressing member may tilt slightly when small size paper is pressed, and a difference in the pressure distribution between the left and right in the Y direction may occur. Even in such a case, as described in this embodiment, it is possible to appropriately adjust the pressure distribution by appropriately adjusting the thickness of the receiving plate support portion 182b. EXAMPLES

[0063] In this embodiment, the position where the pressure force is applied from the lift plate 172 to the metal stay 170 in the heating and pressing unit 167 and the thickness of the receiving plate support portion 182b are changed from those in the previous embodiment 1. This point will be described in detail. Note that the description overlapping with the embodiment 1 will be omitted. FIG. 16(a) is a schematic diagram of the X1-X1' cross section when five sheets of A4 size paper and twenty sheets of A5 size paper are pressed using the heating and pressing unit 167 of this embodiment. The position of the pressure center Fc is the same as the center position Yc of the heating and pressing unit 167 in the Y direction in the embodiment 1, whereas in the embodiment, it is shifted toward the vertical alignment reference position G side from the center position Yc of the heating and pressing unit 167 in the Y direction. By shifting this pressure center Fc toward the vertical alignment reference position G side from the center Yc of the heating and pressing unit 167, a rotation moment M2 opposite to that in the embodiment 1 is applied. As a result, the action of the rotation moment M1 when pressing the A5 size paper caused by the non-pressurized area Sc described in the embodiment 1 can be weakened. In addition, the specific positional relationship of the pressure force is to move the position of K2 25 mm toward the vertical alignment reference position G (L K2 (200 mm)). As a result of the movement of K2, the center of pressure Fc due to the pressure K1 and pressure K2 moves to the center position Yc in the Y direction (distance L Yc From the vertical alignment reference position G, the distance L is 12 mm. Fc FIG. 16(b) shows the thickness of the receiving plate support portion 182b in the X1-X1' cross section. The thickness H at the end Y3 of the sheet width Sa of A4 size paper is Y3is the thickest, and the thickness H at point Y1, which corresponds to the vertical alignment reference position G Y1 and the thickness H at the end Y2 point of the sheet width Sb of A5 size paper Y2 are the same thickness (H Y3 >H Y2 , H Y1 =H Y2 In this embodiment, H Y1 is 2.3mm, H Y2 is 2.3mm, H Y3 The thickness was 2.6 mm. Y2 ~H Y3 The gradient between the two formed a smooth curved surface. Y2 ~H Y3The gradient between the Y1 and Y2 sides is because the pressure on the Y3 side can be increased, and the thickness of the support plate 182b can be appropriately adjusted in consideration of the rotation moment M2 in this embodiment and the deflection of the heating and pressing unit 167. In FIG. 16(c), the stress distribution on the A4 size paper has a minimum value GAmin of the pressure applied to the sheet in the Y2 to Y3 region, but it can exceed the reference surface pressure Gtgt. This is because the thickness of the support plate 182b can be appropriately adjusted in consideration of the influence of the rotation moment and deflection of the heating and pressing unit 167 for the rotation moment M2 consisting of K1 and K2. In the pressure distribution on the A5 size paper, the surface pressure has a gradient from Y1 to Y2 in the Y direction, but the minimum surface pressure GBmin exceeds the reference surface pressure Gtgt. In the pressure distribution on the A5 size paper, the surface pressure has a gradient from Y1 to Y2, but the minimum surface pressure GBmin exceeds the reference surface pressure Gtgt. This is because in this embodiment, the force center Fc from the lift plate 172 to the metal stay 170 is moved toward the vertical alignment reference position G to weaken the action of the rotation moment M1 caused by the non-pressurized area Sc, and a well-balanced state can be maintained. FIG. 15(d) shows the booklet adhesive strength test results in this embodiment. The adhesiveness of E1 to E14 for A4 size paper and F1 to F10 for A5 size paper exceeds the reference adhesive strength of 1.0 N / cm and is good. In this embodiment, as in the first embodiment, the surface pressure distribution can be adjusted to exceed the reference surface pressure Gtgt, so that good adhesive strength can be obtained. Note that sheet alignment is based on one side edge of the sheet, and as for the method of adjusting the pressure distribution when pressing multiple paper sizes, a suitable method may be used from the first embodiment and the second embodiment according to the device configuration of the heating and pressing unit 167. EXAMPLES

[0064] In the above-mentioned first and second embodiments, the sheet alignment method is based on a one-sided reference where one end of the sheet S is aligned at the vertical alignment reference position G of the heating and pressing unit 167. In this embodiment, as shown in FIG. 17, the vertical alignment reference position G' of the heating and pressing unit 167 is set, and the center of the sheet S in the Y direction is aligned as a central reference. The reference position G is not used as an alignment reference position in this embodiment. However, it is used for the purpose of defining positions that overlap with the explanations of the first and second embodiments. The explanations that overlap with the first embodiment will be omitted. FIG. 18(a) is a schematic diagram of the X1-X1' cross section when five sheets of A4 size paper and twenty sheets of A5 size paper are pressed using the heating and pressing unit 167 of this embodiment. The vertical alignment reference position G' described above is the same as the center position Yc of the heating and pressing unit 167 in the Y direction. FIG. 18(b) shows the thickness of the receiving plate support portion 182b in the X1-X1' cross section. In the X1-X1' section, the thickness H at the ends Y2 and Y2' of the sheet width Sb of A5 size paper Y2 , H Y2´ The thinnest is the thickness H, which corresponds to Y1 and Y3 at both ends of the sheet width Sa of A4 size paper. Y1 and H Y3 is H Y2 and H Y2´ Thicker than (H Y1 >H Y2 , H Y3 >H Y2´ ) In addition, the thickness H Yc Also H Y2 and H Y2´ Thicker (H Yc >H Y2 , H Yc >H Y2´ In this embodiment, H Y1 is 2.5mm, H Y2 is 2.3mm, H Yc is 2.4mm, H Y2´ is 2.3mm, H Y3 The thickness was 2.5 mm. Y1 ~H Y3 Any gradient between the two surfaces formed a smooth curved surface. As shown in Figure 18(b), when A5 size paper was pressed, H Y2 <H Yc , HY2´ <H Yc By setting the relationship as above, the pressure applied to the central position Yc can be increased. As a result, as shown in FIG. 18(c), the concentration of pressure applied to the ends Y2 and Y2' of the sheet width Sb of the A5 size paper can be suppressed. Y2 <H Y1 , H Y2´ <H Y3 By setting the relationship, the pressure distribution at the central position Yc can be adjusted to be uniform in the Y direction without increasing the pressure to the central position Yc. In the pressure distribution of A5 size paper in FIG. 18(c), the pressure is approximately uniform in the Y direction from Y2 to Y2', and the minimum pressure GBmin exceeds the reference pressure Gtgt. This is because the sheet S is set as the central reference, and the non-pressurized area when pressing small size paper is uniformly distributed to the left and right at both ends of the heating and pressing unit 167, thereby suppressing the action of the rotation moment M1 as in the first and second embodiments. In addition, in the pressure distribution of A4 size paper, the pressure distribution is approximately uniform from Y1 to Y3 in the Y direction. Although the minimum pressure GAmin of the pressure applied to the sheet occurs in the areas Y1 to Y2 and Y2' to Y3 near Y2 and Y2', it exceeds the reference pressure Gtgt. This is the result of being able to satisfactorily adjust the pressure distribution in the Y direction for different sheet sizes by appropriately adjusting the thickness of the backing plate support portion 182b, taking into consideration the effect of the deflection of the heating and pressing unit 167. In this embodiment, as in the first and second embodiments, the surface pressure distribution can be adjusted to exceed the reference surface pressure Gtgt, so that a good adhesive force can be obtained.

[0065] 19(a) is a schematic diagram of the X1-X1' cross section when five sheets of A4 size paper and twenty sheets of A5 size paper are pressed using the heating and pressing unit 167 of Comparative Example 3. Here, in Comparative Example 3, the thickness of the receiving plate support portion 182b is uniform in the Y direction in the X1-X1' cross section (H Y1 =H Y2 =H Y3= 2.5 mm, see FIG. 19(b). Here, the pressure positions of pressure forces K1 and K2 are the same as in this embodiment. As shown in FIG. 19(c), when A5 size paper is pressed, non-pressurized areas Sd as pressurized intermediate areas are generated on both sides in addition to the A5 width sheet width Sb. At this time, stress is concentrated on both sides (Y2, Y2') of the sheet width Sb. As a result, the pressure plate 169 bends around the center position Yc in the Y direction, and the pressure force GBmin near the center position Yc decreases and falls below the reference surface pressure Gtgt. Note that the pressure force distribution on A4 size paper is uniform, and it is possible to exceed the reference surface pressure Gtgt.

[0066] FIG. 15(f) shows the test results of the booklet adhesive strength when the heating and pressing unit 167 of Comparative Example 3 was used. With A4 size paper, good adhesive strength was obtained at E1 to E14. With A5 size paper, the adhesive strength fell below the reference adhesive strength of 1.0 N / cm at F5 and F6, which corresponds to the center position Yc of the heating and pressing unit 167 in the Y direction. This is because, as described above, the members (heating plate, heater support, metal stay) bend at the center position Yc of the heating and pressing unit 167 in the Y direction, causing the pressure GBmin to fall below the reference surface pressure Gtgt. FIG. 15(e) shows the test results of the booklet adhesive strength when the heating and pressing unit 167 of Example 3 was used. With A5 size paper, when the thickness of the receiving plate support portion 182b was set to H Y2 <H Yc , H Y2´ <H Yc By setting the relationship as above, the pressure applied to the central position Yc can be increased, and good adhesive strength can be obtained in F1 to F10. Y1 >H Y2 , H Yc >H Y2´ By achieving this relationship, the pressure applied to the ends Y1 and Y3 of the A4 sheet width Sa can be increased, resulting in good adhesive strength at E1 to E14. Table 2 shows a list of comparative verification results between this embodiment and Comparative Example 3. The (M) pressure distribution measurement results and (N) booklet adhesive strength measurement results shown in Table 2 are a summary of the contents and verification results described above using Figures 15, 18, and 19. Table 2 is explained below.

[0067] [Table 2]

[0068] (L) Shape of the receiving plate support part In this embodiment, the thickness (H Y1 , H Y2 , H Yc , H Y2´ , H Y3 ) (Fig. 18(b)). Here, the thickness corresponding to the end point of the sheet width Sa of A4 size paper is H Y1 and H Y3 , the thickness of the A5 size paper at the end of the sheet width Sb is H Y2 and H Y2´ The thickness H Yc The shape of the receiving plate support part in this embodiment (L-J3) is the end H of the pressure area for A5 size paper. Y2 , H Y2´ The gradient is set on both sides of the Y direction starting from H Y1 >H Y2 , H Y3 >H Y2 , H Yc >H Y2 , H Yc >H Y2´ On the other hand, the shape (L-H3) of the receiving plate support portion of Comparative Example 3 is configured to have no gradient due to the thickness of the receiving plate support portion 182b (H Y1 =H Y2 =H Y3 ).

[0069] (M) Pressure distribution of the heating and pressurizing unit In this embodiment, the applied pressure can be maintained at or above the reference value (0.4 MPa) for both A4 size paper and A5 size paper (M-J3-1, M-J3-2). On the other hand, in Comparative Example 3, there are some places where the applied pressure falls below the reference value (0.4 MPa) (M-H3-2).

[0070] (N) Booklet adhesive strength In this embodiment, the booklet adhesive strength can be made equal to or greater than the reference value (1.0 N / cm) for both A4 size paper and A5 size paper (N-J3-1, N-J3-2). On the other hand, in Comparative Example 3, there are some places where the booklet adhesive strength falls below the reference value (1.0 N / cm) (N-H3-2). As described above, the method of this embodiment makes it possible to properly adjust the pressure distribution even in the case of a heating and pressurizing unit 167 having a sheet reference position in the center.

[0071] [Note] The above-described embodiments at least disclose the following booklet producing apparatus and image forming system.

[0072] (Item 1) The heat and pressure unit is an elongated heat and pressure unit that heats and presses the adhesive layers of a plurality of overlapping sheets each having an adhesive layer formed thereon, the heat and pressure unit having a pressure plate that contacts and presses the sheets, a heater that heats the pressure plate, a receiving member that faces the pressure plate, and a pressure mechanism that applies pressure to the sheets sandwiched between the pressure plate and the receiving member, A booklet producing apparatus that produces a booklet by sandwiching a plurality of sheets having adhesive layers formed thereon between the pressure plate and the receiving member and applying heat and pressure to the adhesive layers formed on the sheets, When a region of the heating and pressurizing unit in the longitudinal direction of the heating and pressurizing unit where the heating and pressurizing unit heats and pressurizes a maximum size sheet is defined as a first region, a region of the heating and pressurizing unit in the longitudinal direction where the heating and pressurizing unit heats and pressurizes a minimum size sheet is defined as a second region, and a region of the heating and pressurizing unit that is inside the first region and outside the second region in the longitudinal direction is defined as a third region, a minimum value of pressure applied to the sheet in the longitudinal direction when the heating and pressing unit heats and presses the maximum-sized sheet is a position within the third region or an end position of the second region adjacent to the third region, A booklet production device characterized in that within the third area, in the longitudinal direction, there is an area on the opposite side to the second area from the position of the minimum value, where the pressure is greater than the minimum value.

[0073] (Item 2) The booklet production apparatus according to item 1, The booklet producing apparatus according to claim 1, wherein the receiving member includes a receiving plate having elasticity for clamping a sheet together with the pressure plate, and a receiving plate support having a receiving plate support portion for supporting the receiving plate.

[0074] (Item 3) A booklet production apparatus according to item 1 or 2, the heating and pressing unit has a reference position for aligning the sheet on one end side in the longitudinal direction, A booklet production device characterized in that the pressure applied to the sheet when the heating and pressurizing unit heats and pressurizes a maximum-size sheet is higher at the end of the sheet on the side of the reference position in the longitudinal direction than at the end position of the second region adjacent to the third region.

[0075] (Item 4) A booklet production apparatus according to item 1 or 2, the heating and pressurizing unit has a reference position for aligning the sheet at a center portion in the longitudinal direction, A booklet production device characterized in that the pressure applied to the sheet when the heating and pressurizing unit heats and pressurizes the maximum size sheet is higher at the reference position in the longitudinal direction than at the end position of the second region adjacent to the third region.

[0076] (Item 5) A booklet production apparatus according to items 2 to 4, A booklet production device characterized in that the thickness of the backing plate support or the backing plate in the sheet pressure direction is thinnest in the longitudinal direction at a position within the third area or at an end position of the second area adjacent to the third area.

[0077] (Item 6) A booklet production apparatus according to items 2 to 5, A booklet production device characterized in that, in the longitudinal direction, on the opposite side to the side where the second region is located as viewed from the position where the thickness is thinnest, there is an area where the thickness is thicker than the thickness of the backing plate support or the backing plate in the sheet pressure direction at the position where the thickness is thinnest.

[0078] (Item 7) A booklet production apparatus according to items 2 to 6, A booklet production device, characterized in that the thickness of the pressure plate in the sheet pressure direction is thinnest in the longitudinal direction at a position within the third area or at an end position of the second area adjacent to the third area.

[0079] (Item 8) A booklet production apparatus according to any one of items 2 to 7, A booklet production device characterized in that, in the longitudinal direction, on the opposite side to the side where the second region is located as viewed from the position where the thickness is thinnest, there is an area where the thickness is thicker than the thickness of the pressure plate in the sheet pressure direction at the position where the thickness is thinnest. [Explanation of symbols]

[0080] 167 Heating and Pressurizing Unit 168 Ceramic heater (heating body) 169 Pressure Plate 180 Supporting member 181 Support plate 182 Backing plate support 182b Backing plate support

Claims

1. The heat and pressure unit is an elongated heat and pressure unit that heats and presses the adhesive layers of a plurality of overlapping sheets each having an adhesive layer formed thereon, the heat and pressure unit having a pressure plate that contacts and presses the sheets, a heater that heats the pressure plate, a receiving member that faces the pressure plate, and a pressure mechanism that applies pressure to the sheets sandwiched between the pressure plate and the receiving member, A booklet producing apparatus that produces a booklet by sandwiching a plurality of sheets having adhesive layers formed thereon between the pressure plate and the receiving member and applying heat and pressure to the adhesive layers formed on the sheets, When a region of the heating and pressurizing unit in the longitudinal direction of the heating and pressurizing unit where the heating and pressurizing unit heats and pressurizes a maximum size sheet is defined as a first region, a region of the heating and pressurizing unit in the longitudinal direction where the heating and pressurizing unit heats and pressurizes a minimum size sheet is defined as a second region, and a region of the heating and pressurizing unit that is inside the first region and outside the second region in the longitudinal direction is defined as a third region, a minimum value of pressure applied to the sheet in the longitudinal direction when the heating and pressing unit heats and presses the maximum-sized sheet is a position within the third region or an end position of the second region adjacent to the third region, A booklet production device characterized in that within the third area, in the longitudinal direction, there is an area on the opposite side to the second area from the position of the minimum value, where the pressure is greater than the minimum value.

2. 2. The booklet producing apparatus according to claim 1, wherein the receiving member includes a receiving plate having elasticity for clamping the sheet together with the pressure plate, and a receiving plate support having a receiving plate support portion for supporting the receiving plate.

3. the heating and pressing unit has a reference position for aligning the sheet on one end side in the longitudinal direction, The booklet production device according to claim 1, characterized in that the pressure applied to the sheet when the heating and pressurizing unit heats and pressurizes a maximum-size sheet is higher at the end of the sheet on the side of the reference position in the longitudinal direction than at the end position of the second region adjacent to the third region.

4. the heating and pressurizing unit has a reference position for aligning the sheet at a center portion in the longitudinal direction, The booklet production device according to claim 1, characterized in that the pressure applied to the sheet when the heating and pressurizing unit heats and pressurizes the maximum size sheet is higher at the reference position in the longitudinal direction than at the end position of the second region adjacent to the third region.

5. 3. A booklet production apparatus as described in claim 2, characterized in that the thickness of the backing plate support or the backing plate in the sheet pressure direction is thinnest in the longitudinal direction at a position within the third region or at an end position of the second region adjacent to the third region.

6. A booklet production device as described in claim 5, characterized in that in the longitudinal direction, on the opposite side to the side where the second region is located as viewed from the position where the thickness is thinnest, there is an area where the thickness is thicker than the thickness of the backing plate support or the backing plate in the sheet pressure direction at the position where the thickness is thinnest.

7. 2. The booklet producing apparatus according to claim 1, wherein the thickness of the pressure plate in the sheet pressing direction is thinnest in the longitudinal direction at a position within the third region or at an end position of the second region adjacent to the third region.

8. A booklet production device as described in claim 7, characterized in that in the longitudinal direction, on the opposite side to the side where the second region is located as viewed from the position where the thickness is thinnest, there is an area where the thickness is thicker than the thickness of the pressure plate in the sheet pressure direction at the position where the thickness is thinnest.

9. A booklet producing apparatus according to any one of claims 1 to 8, an image forming apparatus for forming an adhesive layer on a sheet; An image forming system comprising:

Images