Booklet binding apparatus and image forming system

Abstract

A booklet binding apparatus including a clamp mechanism for clamping a sheet bundle, a coating member for applying adhesive to the spine surface of the sheet bundle clamped by the clamp mechanism, and an attaching and detaching mechanism for moving the coating member to and from the spine surface of the sheet bundle, wherein the attaching and detaching mechanism includes a separation mechanism which makes the coating member to be detached from the spine surface of the sheet bundle when an abnormal incident has occurred during application of the adhesive.

Description

This application is based on Japanese Patent Application No. 2005-251003 filed on Aug. 31, 2005 in Japanese Patent Office, the entire content of which is hereby incorporated by reference.

BACKGROUND OF THE INVENTION

This invention relates to a booklet binding apparatus which produces booklets by adhesion and to an image forming system equipped with the booklet binding apparatus.

Because of the advantages of meeting the requirements for small lot production, shorter delivery time and reduced costs, an image forming apparatus based on color electrophotographic technology has come into use in recent years to take the place of the conventional printing apparatus. The use of a booklet binding apparatus also has been considered, wherein a predetermined number of the sheets with an image formed thereon by an image forming apparatus are aligned to form a bundle of sheets and a paste is applied to the spine surface of the bundle of sheets so that a cover sheet is bonded thereon for producing a booklet.

Among such kinds of booklet binding apparatuses, for the purpose of an enhancement of workability and quality, an apparatus which applies adhesive to the spine surface of the sheet bundle and attaches a cover sheet to the sheet bundle has been disclosed, wherein the edges of the cover sheet can be easily aligned to the edges of the sheet bundle on the opposite side of the spine portion and firmly glued to the sheet bundle (Patent Document 1, for example).

However, if electric power to the book binding apparatus of Patent Document 1 is shut off accidentally or involuntarily by the operator while the adhesive application is in progress, the coating roller may be stuck to the spine surface of the sheet bundle with the adhesive and it may take long time and much labor to separate the coating roller from the bundle of sheets when recovering the apparatus. Particularly, when a hot-melt adhesive is used to shorten bonding time and to obtain a strong bonding force, it may require more time and labor to melt the adhesive and separate the coating roller from the sheet bundle.

[Patent Document 1] Unexamined Japanese Patent Application Publication No. 2004-209753

SUMMARY

The present invention includes the following structures:

(1) A booklet binding apparatus including: a clamp mechanism for clamping a bundle of sheets; a coating member for coating adhesive on an end surface of the bundle of sheets clamped by the clamp mechanism; an attaching and detaching mechanism for attaching the coating member to the end surface of the bundle of sheets and for detaching the coating member from the end surface; and a separation mechanism for detaching the coating member from the end surface of the bundle of sheets, when an abnormal incident occurs during coating of adhesive on the end surface of the bundle of sheets by the coating member.

(2) An image forming system including: an image forming apparatus having an image forming section for forming an image on a sheet; a booklet binding apparatus for producing a booklet by receiving a plurality of sheets from the image forming apparatus, the booklet binding apparatus having; a clamp mechanism for clamping a bundle of sheets; a coating member for coating adhesive on an end surface of the bundle of sheets clamped by the clamp mechanism; an attaching and detaching mechanism for attaching the coating member to the end surface of the bundle of sheets and for detaching the coating member from the end surface; and a separation mechanism for detaching the coating member from the end surface of the bundle of sheets, when an abnormal incident occurs during coating of adhesive on the end surface of the bundle of sheets by the coating member.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view of the entire image forming system in which an image forming apparatus is connected to a booklet binding apparatus.

FIG. 2 is a front sectional view of booklet binding apparatus.

FIG. 3 is an explanatory drawing (1) of a booklet binding process.

FIG. 4 is an explanatory drawing (2) of a booklet binding process.

FIG. 5 is an explanatory drawing (3) of a booklet binding process.

FIG. 6 is a top view of coating unit 60 of FIG. 1.

FIG. 7 is a sectional view taken on line X-X of FIG. 6.

FIG. 8 is a sectional view taken on line Y-Y of FIG. 6.

FIG. 9 is a control diagram of the booklet binding apparatus.

FIG. 10 is a schematic process diagram for attaching the coating roller and the leveling roller to the spine surface of a sheet bundle and for detaching them from the surface.

FIG. 11 is another preferred embodiment (1) of an attaching and detaching mechanism.

FIG. 12 is still another preferred embodiment (2) of an attaching and detaching mechanism.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

One of the preferred embodiments of the present invention will be explained below referring to drawings.

It should be made clear that the following description does not impose restrictions on the technical scope or terminology of what is claimed. The assertive description in the embodiment of the present invention indicates the best mode, without the terminology or technical scope of the present invention being restricted thereby.

FIG. 1 is a schematic view of the entire image forming system in which an image forming apparatus A is connected to a booklet binding apparatus B relating to a preferred embodiment of the present invention.

The image forming apparatus A will be explained first.

Image forming apparatus A electrophotographically forms images on sheets which are transfer materials and is equipped with image forming section A1, document feeder A2, and image reader A3.

Image forming section A1 has charging unit 2, exposing unit 3, developing unit 4, transfer unit 5A, separating unit 5B, and cleaning unit 6 around drum-shaped photoreceptor 1. These electrophotographic units perform charging, exposure, development, and transferring in order to form a toner image on the surface of photoreceptor 1 and an image on sheet S.

Sheets S are stored in three sheet trays 7A, and delivered one by one from trays 7A to transfer unit 5A. Sheet S receives a toner image there from photoreceptor 1 by transfer unit 5A.

Sheet S with a toner image transferred on it is delivered by conveying belt 7B to fixing unit 8 and fixed there. Fixed sheet S is ejected by ejection rollers 7C or delivered to sheet re-feeding path 7E.

When sheet S is ejected with its face up, switching gate 7D delivers sheet S straight. When sheet S is ejected with its face down or when sheet S has images on both surfaces, switching gate 7D delivers sheet S downward.

When sheet S is ejected with its face down, sheet S is guided downward, switched back to move up, and ejected by ejection rollers 7C.

In the double-sided print mode, sheet S is guided downward, turned upside down with a switchback, delivered to a transfer section which includes transfer unit 5A through the sheet re-feeding path 7E, and receives another image on the other surface of sheet S. Then sheet S is sent to fixing device 8, and fixed there, and then ejected.

Document feeder A2 feeds documents one by one to a reading position. Image reader A3 reads the image on a document which is fed from document feeder A2 or placed on document table 9 and generates an image signal.

Then, booklet binding apparatus B is outlined below with reference to FIG. 1.

Booklet binding apparatus B receives sheets S from image forming apparatus A, bundles them into a sheet bundle S1, bonds a sheet for cover sheet S2 (hereinafter, simply called a cover sheet) to sheet bundle S1, and thus forms booklet S3.

Booklet binding apparatus B is equipped with sheet conveying section 10 which delivers sheet S ejected from image forming apparatus A to ejection tray 20 or sheet reversing section 40, clamp unit 50 which receives one or more sheets S, bundles them into sheet bundle S1, and clamps the bundle, coating unit 60 which applies adhesive such as a hot-melt adhesive to the spine surface of sheet bundle S1, cover sheet storage section 70 which stores cover sheets S2, cover sheet supporting unit 80 which receives cover sheet S2 from cover sheet storage section 70 and support thereof, and booklet ejecting section 100.

Sheet S ejected from image forming apparatus A is delivered to switching gate 11 in sheet conveying section 10. The switching gate 11 changes sheet paths to send sheet S to ejection tray 20 via ejection path 12 or to sheet reversing section 40. In the non-bookbinding mode, sheets S are ejected to ejection tray 20.

In the bookbinding mode, sheet S is sent to sheet reversing section 40 via sheet conveying path 13, switched back by sheet reversing section 40, and delivered to clamp unit 50. When a preset number of sheets are stacked in clamp unit 50, sheet bundle S1 is turned and held almost vertically.

Coating unit 60 applies adhesive to the bottom surface of sheet bundle S1 which is held vertically.

Cover sheet S2 supplied from cover sheet storage section 70 and being supported by cover sheet supporting unit 80 is raised, brought into contact with sheet bundle S1 which has been coated with adhesive to be bonded to it.

Booklet S3 made by bonding cover sheet S2 to sheet bundle S1 is ejected to booklet ejecting section 100.

Booklet binding apparatus B in the bookbinding mode will be explained below in more details with reference to FIG. 2.

FIG. 2 is a front sectional view of booklet binding apparatus B.

Sheet S conveyed through sheet conveying path 13 moves diagonally upward by conveying rollers 401 and 402 on tilted reversing plate 403, then moves downward by the reverse rotation of conveying rollers 402, bumps into stopper 404, and stops there.

When a predetermined number of sheets S are stacked on reversing plate 403, feed-in rollers 405 which have been separated from each other, nip the sheets S, and carry them downward. The sheets are supported at a slant by clamp unit 50 which is equipped with supporting plate 502 and stopping plate 503.

As to be explained later, after clamping sheet bundle S1 the tilted clamp unit 50 stands vertically. Adhesive is applied to the spine surface of sheet bundle S1 and cover sheet S2 is bonded to sheet bundle S1. This completes booklet S3. During a time interval before clamp unit 50 returns to the tilted position again, no sheet S cannot be fed into clamp unit 50. Incoming sheets S must be stood by on reversing plate 403 during this time interval. The number of sheets stood by on the reversing plate 403 is equivalent to the aforementioned predetermined number of sheets.

The booklet S3 is completed and after returning to the tilted position, clamp unit 50 can stack sheets S thereon. Each sheet S fed by sheet conveying rollers 401 is one by one delivered into clamp unit 50 by sheet conveying rollers 402 until reversing plate 403 receives a preset number of sheets which have been preset to form a booklet at the operation and display unit A5 (see FIG. 1) of image forming apparatus A.

When a preset number of sheets have been stacked in clamp unit 50, the sheet bundle S1 is clamped between supporting plate 502 and clamp plate 504 driven by a driving unit (not shown in the figure) and turned to stand vertically from the tilted state when clamp unit 50 rotates around axis 505.

When sheet bundle S1 stands vertically, stopping plate 503 retracts and coating unit 60 moves perpendicularly to the sheet surface on which FIG. 2 is illustrated to apply adhesive to the spine surface of sheet bundle S1.

Then, cover sheet S2 is delivered from sheet tray 701 of cover sheet storage section 70 provided in a lower portion of booklet binding apparatus B by delivery rollers 702, held flat horizontally on cover sheet supporting unit 80, and lifted up until it is brought into contact with the spine surface of sheet bundle S1 with lifting unit 90, and then bonded there to make a booklet S3. The resulting booklet S3 is ejected to booklet ejecting section 100.

The following describes the details of the process of binding a booklet S3 with reference to FIG. 3, FIG. 4, and FIG. 5.

As already explained, in FIG. 3(a), the sheets S having been conveyed from the image forming apparatus A are delivered diagonally upward by the sheet conveying rollers 401 and 402, and are stacked on the sheet reversing section 40 until a predetermined number is reached. After that, the sheets S are fed diagonally downward by the feed-in roller 405, and are stacked on the supporting plate 502 of clamp unit 50.

After a predetermined number of sheets S have been stacked on the supporting plate 502 one by one, the sheet bundle S1 is clamped by the supporting plate 502 through the operation of the clamp plate 504. After having been clamped, the sheet bundle S1 in the tilted position is placed upright, and the stopping plate 503 retracts. While moving perpendicularly to the sheet surface of FIG. 3, the coating unit 60 applies adhesive such as a hot-melt adhesive to the spine surface SA of the sheet bundle S1 (see FIG. 3(b)).

The structure and operation of the coating unit 60 characteristic of the present invention will be described later.

As shown in the lower part of FIG. 3(c), in parallel with the aforementioned series of operations, the cover sheet S2 conveyed from cover sheet storage section 70 (see FIG. 2) is fed into a predetermined position by the cover sheet feed-in rollers 801 and 802 and are placed in a horizontal position.

After application of the adhesive to the spine surface SA of the sheet bundle S1, the lifting unit 90 (see FIG. 2) lifts the cover sheet supporting unit 80 until the fixing plate 803 is engaged with the spine surface SA of sheet bundle S1 through the cover sheet S2.

As shown in the upper part of FIG. 3(c), to prevent the cover sheet S2 from being pulled by a pair of folding members 804 provided above the fixing plate 803 and the cover sheet feed-in rollers 801 and 802, the nipping of cover sheet feed-in rollers 801 and 802 is released interlocked with the rising of the cover sheet supporting unit 80.

When the fixing plate 803 is engaged with the spine surface SA of sheet bundle S1, the pair of folding members 804 move closer to each other, as shown in FIG. 4(a), and the cover sheet S2 is bonded with sheet bundle S1 in a rectangular form. Then the folding members go back to the initial position.

When the cover sheet S2 has been bonded to the sheet bundle S1, the cover sheet supporting unit 80 starts to go down. In synchronism with this movement, the follower roller supporting levers 805 and 806 of the cover sheet feed-in rollers 801 and 802 rotate in opposite directions, clockwise and counterclockwise, respectively, shown in FIG. 4. The cover sheet supporting levers 807 and 808 also rotate clockwise and counterclockwise to support sheet cover S2.

As will be explained later, the booklet conveyor 810 moves perpendicularly to the sheet surface of FIG. 4 to receive and eject the booklet S3 having been bound. In this case, the cover sheet supporting unit 80 goes down until the booklet conveyor 810 does not touch the edge of the cover sheet S2.

When cover sheet supporting unit 80 has moved down, the pair of booklet conveyors 810 having retracted outwardly of the length (width) of the sheet bundle S1 in the direction perpendicular to the sheet surface of FIG. 4 come closer to each other until they reach the position of supporting the sheet bundle S1 (see FIG. 4(b)).

After the movement of the booklet conveyor 810 ends, to alleviate the shock of the booklet S3 falling on the booklet conveyor 810, the booklet conveyor 810 comes closer to the spine surface SA of the sheet bundle S1 and stops there (see FIG. 4(c)).

After the cover sheet supporting unit 80 has stopped, the clamp plate 504 unclamps the sheet bundle S1 to allow booklet S3 to fall onto the booklet conveyor 810 (see FIG. 5(a)). In this case, cover sheet supporting lever 808 is back in an initial horizontal position.

After the booklet S3 has fallen on booklet conveyor 810, the cover sheet supporting unit 80 starts to go down. The booklet S1 led by its spine surface SA is fed (see FIG. 5(b)) while falling onto the conveyor 810 running in the arrow direction shown in FIG. 5(b). The booklet S3 then lies flat on the conveyor 810, and is ejected out of the apparatus (see FIG. 5(c)).

When the booklet S3 has been ejected, the aforementioned component members return to their initial positions.

The following describes the coating unit 60 with reference to FIG. 6, FIG. 7, and FIG. 8.

FIG. 6 is a top view of the coating unit 60 given in FIG. 1. FIG. 7 is a sectional view taken on the line X-X of FIG. 6. FIG. 8 is a sectional view taken on the line Y-Y of FIG. 6.

As shown in FIG. 6, 601 denotes a coating roller as a coating member to apply adhesive. This roller is rotatably supported by the first swinging unit 602 designed in an approximately box-like form. As shown in FIG. 8, part of the coating roller 601 is immersed in the adhesive AD such as a hot-melt adhesive, which is stored in the first swinging unit 602 and is melted by a heater 603.

As shown in FIG. 6 and FIG. 7, the reference numeral 604 indicates a leveling roller for smoothening the adhesive applied to spine surface SA of sheet bundle S1. The leveling roller 604 is rotatably supported by the first swinging unit 602 and the approximately box-shaped second swinging unit 605. A gear G1 is mounted on the rotary shaft 604A of the leveling roller 604.

As shown in FIG. 6, the gear G1 is engaged with the gear G3 fastened to the rotary shaft 601A of the coating roller 601 through the idle gear G2. Further, as shown in FIG. 7, the gear G1 is engaged with the gear G4 which is fastened to the output shaft of the coating motor Ml held by the second swinging unit 605.

This configuration allows the rotation of the coating motor M1 to be transmitted to the coating roller 601 and the leveling roller 604.

As shown in FIG. 6 and FIG. 7, numeral 606 indicates an approximately box-shaped coating unit body provided outside the second swinging unit 605. This unit rotatably supports the second swinging shaft 607 fastened to the second swinging unit 605.

Further, as shown in FIG. 6 and FIG. 7, four slide bearings 608 are provided on upper portions of the coating unit 606 and are slidably engaged with the slide shafts 609 and 610. The slide shafts 609 and 610 are so disposed that the coating unit 606 can travel perpendicularly to the sheet surface of FIG. 1.

As shown in FIG. 6, numeral 611 represents the belt for allowing the coating unit 606 to slide. One part of the belt 611 is fastened to one of the slide bearings 608 through a linking member 612.

The belt 611 is engaged with the pulleys 613 and 614 which are provided in parallel with the slide shafts 609 and 610. The pulley 614 is driven by the traveling motor M2.

As shown in FIG. 8, the reference numeral 615 indicates a first solenoid for causing the first swinging unit 602 of FIG. 8 to swing counterclockwise around the rotary shaft 604A of the leveling roller 604. This solenoid is fastened to the second swinging unit 605. The reference numeral 616 denotes a second solenoid for causing the second swinging unit 605 (in FIG. 8) to swing clockwise around the second swinging shaft 607 arranged rotatably on the coating unit 606. This solenoid is fastened to the coating unit 606.

As illustrated in FIG. 8, the strokes of plungers of the first solenoid 615 and second solenoid 616 are set to ensure that the peripheries of coating roller 601 and leveling roller 604 will have the same height to touch spine surface SA of sheet bundle S1, when the first solenoid 615 and second solenoid 616 are energized and their plungers pop up.

As shown in FIG. 8, numeral 617 indicates a detection device for detecting the sides SS1 and SS2 of sheet bundle S1 positioned perpendicular to spine surface SA of the sheet bundle S1. The device 617 is provided integrally on the front side of the coating unit 606 in the direction indicated by an arrow.

Similarly, in FIG. 8, numeral 618 indicates a regulating plate for regulating the quantity of the adhesives AD stuck to the surface of coating roller 601 and is provided at a preset clearance from the coating roller 601. The reference numeral 619 denotes a scraper plate for removing the adhesive AD from the leveling roller 604, and is held in engagement with the leveling roller 604 at a predetermined pressure.

Both the coating roller 601 and leveling roller 604 are designed to rotate in the arrow direction of FIG. 8.

It should be noted that the coating roller 601 houses a rod-like heater (not illustrated).

As is clear from the aforementioned description, the clamp unit 50 is equipped with a clamp plate 504, a supporting plate 502 and others. The coating unit 60 is equipped with a coating roller 601, a leveling roller 604, a coating motor Ml and others. The traveling unit 61 includes a slide bearing 608, slide shafts 609 and 610, a belt 611, a traveling motor M2 and others. The attaching and detaching mechanism is provided with a first solenoid 615. The mechanism to attach and detach the leveling member is equipped with a second solenoid 616. The cover sheet supporting unit 80 includes cover sheet feed-in rollers 801 and 802, a fixing plate 803, a folding member 804, follower roller supporting levers 805 and 806, cover sheet supporting levers 807 and 808, and a booklet conveyor 810.

Referring to FIG. 9, the following describes the control-related configuration of the booklet binding apparatus B characterized by the aforementioned structure.

The reference numeral B1 represents a control unit of the booklet binding apparatus B, and is equipped with a memory B2 which stores the procedures and data for controlling the booklet binding apparatus B, a CPU (reference numeral B3) which executes control according to the control procedures and data in the memory B2, and others.

Control unit B1 is designed capable of communicating with the control unit A4 (see FIG. 1) of the superordinate image forming apparatus A via the interface B4, and receives information on the sheet size and the preset number of sheets. The input side of the control unit B1 is connected with the detection device 617. The output side is connected with a clamp unit 50, a coating motor M1, a traveling motor M2, a first solenoid 615, a second solenoid 616 and others.

The control unit B1 receives electric power such as the AC, for example, from other power supply line PL and supplies predetermined power to the first solenoid 615, second solenoid 616, and other components via the power supply unit B5 provided in the control unit B1.

The following describes the procedures for applying adhesive in the booklet binding apparatus B of the aforementioned structure with reference to FIG. 10 and other aforementioned drawings:

FIG. 10 is a schematic diagram representing the process of moving the coating roller 601 and the leveling roller 604 to and from the spine surface SA of a sheet bundle S1.

The coating unit 60 stands by at the initial position corresponding to the left portion of FIG. 10, while the coating roller 601 and leveling roller 604 are rotating.

As shown in FIG. 3(a), when the sheet bundle S1 is set upright by the clamp unit 50, the traveling motor M2 (see FIG. 6) rotates to move the coating unit 60 to the right in FIG. 10.

The coating unit 60 moves and the detection device 617 detects the side SS1 of the sheet bundle S1. When a predetermined time (T1) has passed thereafter, the first solenoid 615 actuates (see FIG. 8) to move the coating roller 601 to an end of the spine surface SA of the sheet bundle, whereby adhesive is applied to the spine surface. Simultaneously, the second solenoid 616 also actuates, and the leveling roller 604 is moved up to a workable position for the leveling operation.

The coating unit 606 moves and the detection device 617 detects the side SS2 of the sheet bundle S1. When a predetermined time (T2) has passed thereafter, the first solenoid 615 becomes inactivated, and the coating roller 601 is detached from the end of the spine surface SA of the sheet bundle S1.

Similarly, when a predetermined time (T3) has passed subsequent to the detection of the side SS2 of the sheet bundle S1 by the detection device 617, the second solenoid 616 becomes inactivated, and the leveling roller 604 is detached from the end of the spine surface SA, whereby the adhesive leveling operation terminates.

In the return process subsequent to coating and leveling operations, the coating roller 601 and leveling roller 604 are controlled to be detached from the spine surface SA of the sheet bundle, and to return to their initial positions.

In the aforementioned structure, for example, if the power supply from the power line PL is suspended during the process of coating the adhesive AD, due to power failure, inadvertent interruption of the operation of the booklet binding apparatus B, or a trouble of the power supply unit B5, the power supply to the first solenoid 615 and second solenoid 616 is discontinued, and their plungers retract. At the same time, the coating roller 601 and leveling roller 604 are automatically separated from the spine surface SA of the sheet bundle S1 by the weight of the coating unit 60.

In the aforementioned embodiment, the separation mechanism can be defined as follows.

When power supplied to the first solenoid 615 and second solenoid 616 is shut off, the first swinging unit 602 and second swinging unit 605 are made to rotate around the rotary shaft 604A of the leveling roller 604 and second swinging shaft 607, respectively, by the weight of the coating unit 60, whereby the coating roller 601 and leveling roller 604 are separated from the spine surface SA of the sheet bundle S1.

As explained above, the present embodiment is provided with a mechanism for separating the coating roller 601 and leveling roller 604 from the spine surface SA of the sheet bundle S1 when an abnormal incident occurs during the process of applying adhesives AD. This arrangement eliminates a trouble of the coating roller 601 and leveling roller 604 being left attached to the spine surface SA of the sheet bundle S1. This ensures easy recovery of the booklet binding apparatus from a trouble.

In the aforementioned embodiment, the coating unit 60 includes both the coating roller 601 and leveling roller 604. It is also possible to make such arrangements that the coating unit 60 includes the coating roller 601 alone.

Further, in the aforementioned embodiment, binding of the booklet S3 is achieved by bonding the cover sheet S2 to he sheet bundle S1. It is also possible to bind a booklet by bonding sheet bundle S1 alone with adhesive.

Further, the solenoid as an attaching and detaching mechanism can be replaced by an eccentric cam 620 given in FIG. 11, for vertical traveling of the first swinging unit 602. In this configuration, the coating roller 601 touches the spine surface SA of the sheet bundle just before the eccentric cam 620 reaches the highest position (upper dead point). Thus, if an abnormal incident occurs during the application of adhesive and it discontinues the supply of power to the drive motor (without a reference number) for driving the eccentric cam 620, the eccentric cam 620 is rotated in the arrow direction by the weight of coating unit 60, with the result that the coating roller 601 is separated from the spine surface SA of the sheet bundle S1.

The second swinging unit 605 (see FIG. 8) has a similar attaching and detaching function, and the description thereof will be omitted to avoid duplication.

In addition to the aforementioned examples, links 630 and 631 can be used as the attaching and detaching mechanism to move the coating unit 60 to and from the spine surface SA of the sheet bundle, as shown in FIG. 12. In this configuration, the coating roller 601 touches the spine surface SA of the sheet bundle S1 just before the dead point DP of the links 630 and 631. If an abnormal incident occurs during application of the adhesive and it discontinues the supply of power to the drive motor (without reference number) for driving the links 630 and 631, the links 630 and 631 are inclined in the arrow-marked direction by the weight of coating unit 60, with the result that the coating roller 601 is detached from the spine surface SA of the sheet bundle S1.

The second swinging unit 605 (see FIG. 8) can be configured in the similar manner, and the description thereof will be omitted avoid duplication.

Claims

1. A booklet binding apparatus comprising:

a clamp mechanism for clamping a bundle of sheets;

a coating member for coating adhesive on an end surface of the bundle of sheets clamped by the clamp mechanism;

an attaching and detaching mechanism for attaching the coating member to the end surface of the bundle of sheets and for detaching the coating member from the end surface; and

a separation mechanism for detaching the coating member from the end surface of the bundle of sheets, when an abnormal incident occurs during coating of adhesive on the end surface of the bundle of sheets by the coating member.

2. The booklet binding apparatus of claim 1,

wherein the attaching and detaching mechanism has a solenoid for attaching the coating member to an end surface of a bundle of sheets and for detaching the coating member from the end surface, and the separation mechanism detaches the coating member from the end surface of the bundle of sheets by cutting off electricity supply to the solenoid.

3. The booklet binding apparatus of claim 1,

wherein the attaching and detaching mechanism has a cam for attaching the coating member to an end surface of a bundle of sheets and for detaching the coating member from the end surface, and the separation mechanism detaches the coating member from the end surface of the bundle of sheets by cutting off driving force to the cam.

4. The booklet binding apparatus of claim 1,

wherein the attaching and detaching mechanism has a link mechanism for attaching the coating member to an end surface of a bundle of sheets and for detaching the coating member from the end surface, and the separation mechanism detaches the coating member from the end surface of the bundle of sheets by cutting off driving force to the link mechanism.

5. An image forming system comprising:

an image forming apparatus having an image forming section for forming an image on a sheet;

a booklet binding apparatus for producing a booklet by receiving a plurality of sheets from the image forming apparatus, the booklet binding apparatus comprising;

a clamp mechanism for clamping a bundle of sheets;

a coating member for coating adhesive on an end surface of the bundle of sheets clamped by the clamp mechanism;

an attaching and detaching mechanism for attaching the coating member to the end surface of the bundle of sheets and for detaching the coating member from the end surface; and

a separation mechanism for detaching the coating member from the end surface of the bundle of sheets, when an abnormal incident occurs during coating of adhesive on the end surface of the bundle of sheets by the coating member.

6. The image forming system of claim 5,

wherein the attaching and detaching mechanism has a solenoid for attaching the coating member to an end surface of a bundle of sheets and for detaching the coating member from the end surface, and the separation mechanism detaches the coating member from the end surface of the bundle of sheets by cutting off electricity supply to the solenoid.

7. The image forming system of claim 5,

wherein the attaching and detaching mechanism has a cam for attaching the coating member to an end surface of a bundle of sheets and for detaching the coating member from the end surface, and the separation mechanism detaches the coating member from the end surface of the bundle of sheets by cutting off driving force to the cam.

8. The image forming system of claim 5,

wherein the attaching and detaching mechanism has a link mechanism for attaching the coating member to an end surface of a bundle of sheets and for detaching the coating member from the end surface, and the separation mechanism detaches the coating member from the end surface of the bundle of sheets by cutting off driving force to the link mechanism.