Sheet laminator and image forming system incorporating the sheet laminator

A sheet laminator includes a fuser pressure member, a conveyor, and a guide. The fuser pressure member thermally fixes a two-ply sheet and a sheet medium inserted between two sheets of the two-ply sheet. The conveyor conveys the two-ply sheet toward the fuser pressure member in a sheet conveyance direction. The guide guides the two-ply sheet in a sheet conveyance passage between the conveyor and the fuser pressure member. At least one of the fuser pressure member or the conveyor is operable to guide the two-ply sheet outside the sheet conveyance passage in response to an occurrence of an abnormal stop of the sheet laminator.

CROSS-REFERENCE TO RELATED APPLICATIONS

This patent application is based on and claims priority pursuant to 35 U.S.C. § 119(a) to Japanese Patent Application Nos. 2022-095011, filed on Jun. 13, 2022, and 2023-061817, filed on Apr. 6, 2023, in the Japan Patent Office, the entire disclosure of each of which is hereby incorporated by reference herein.

BACKGROUND

Technical Field

Embodiments of the present disclosure relate to a sheet laminator and an image forming system incorporating the sheet laminator.

Background Art

Various types of jam processing apparatuses in the art are known that, when a paper jam occurs with an object to be conveyed being nipped between a registration roller pair and a fixing roller pair, the registration roller pair is rotated in the forward direction and the fixing roller pair is rotated in the reverse direction, so that the object is conveyed out of a regular sheet conveyance passage and is bent to convey to a jammed sheet ejection passage.

However, such jam processing apparatuses in the art include a guide plate disposed between the registration roller pair and the fixing roller pair and need to further include another guide plate or a conveyance roller to convey the jammed object out of the regular sheet conveyance passage and nips the bend of the object to convey the jammed object to a jammed sheet ejection unit. Due to such a configuration, the number of parts increases, and this increase in the number of parts makes the configuration of the apparatus more complex and hinders a size reduction of the apparatus.

A typical jam processing apparatus has a passage separated to the outside of the sheet conveyance passage from an intermediate area between the registration roller pair and the fixing roller pair. When a paper jam occurs, the registration roller pair is rotated in the conveyance direction and the fixing roller pair is rotated in the reverse direction to guide the jammed sheet to the jammed sheet ejection passage while a bend is being formed on the jammed sheet, so that the jammed sheet is conveyed to the jammed sheet ejection unit with a sheet ejection roller pair that conveys the jammed sheet while nipping the bend of the jammed sheet. By so doing, the jammed sheet nipped by the registration roller pair and the fixing roller fixing roller pair can be removed automatically from the sheet conveyance passage.

However, since a paper discharge guide and a pair of paper discharge rollers for removing the jammed paper are provided, the size of the apparatus cannot be reduced, and the demand for space saving cannot be satisfied.

SUMMARY

Embodiments of the present disclosure described herein provide a novel sheet laminator including a fuser pressure member, a conveyor, and a guide. The fuser pressure member thermally fixes a two-ply sheet and a sheet medium inserted between two sheets of the two-ply sheet. The conveyor conveys the two-ply sheet toward the fuser pressure member in a sheet conveyance direction. The guide guides the two-ply sheet in a sheet conveyance passage between the conveyor and the fuser pressure member. At least one of the fuser pressure member or the conveyor is operable to guide the two-ply sheet outside the sheet conveyance passage in response to an occurrence of an abnormal stop of the sheet laminator.

Further, embodiments of the present disclosure described herein provide an image forming system including the above-described sheet laminator and an image forming apparatus to form an image on a sheet medium to be fed to the sheet laminator.

DETAILED DESCRIPTION

It will be understood that if an element or layer is referred to as being “on,” “against,” “connected to” or “coupled to” another element or layer, then it can be directly on, against, connected or coupled to the other element or layer, or intervening elements or layers may be present. In contrast, if an element is referred to as being “directly on,” “directly connected to” or “directly coupled to” another element or layer, then there are no intervening elements or layers present. As used herein, the term “connected/coupled” includes both direct connections and connections in which there are one or more intermediate connecting elements. Like numbers refer to like elements throughout. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items.

A description is given of a sheet processing device according to an embodiment of the present disclosure, with reference toFIG.1.

FIG.1is a schematic diagram illustrating an overall configuration of a sheet laminator according to an embodiment of the present disclosure.

A sheet laminator100according to the present embodiment is to separate two sheets (plies) of a two-ply sheet (hereinafter referred to as a lamination sheet S) and to insert and sandwich a sheet-shaped medium (hereinafter referred to as an inner sheet P) between the separated sheets of the two-ply sheet.

The lamination sheet S is a two-ply sheet in which two sheets are overlapped and bonded together at a portion (or a side) of the two-ply sheet. For example, a two-ply sheet has two sheets (two sides). A first side of the two-ply sheet serves as a transparent sheet such as a transparent polyester sheet, a second side of the two-ply sheet serves as a transparent or opaque sheet is disposed facing the first side, and the first and second sides are bonded at one side of the two-ply sheet. The two-ply sheet also includes a lamination film.

The inner sheet P is an example of the sheet medium that is inserted into the two-ply sheet. The sheet medium may be, for example, thick paper, postcards, envelopes, plain paper, thin paper, coated paper, art paper, tracing paper, and overhead projector (OHP) transparencies.

As illustrated inFIG.1, the sheet laminator100includes a sheet tray102serving as a first stacker that stacks lamination sheets S, a pickup roller105that feeds the lamination sheets S from the sheet tray102, and first conveyance roller pair107. In the sheet tray102of the sheet laminator100, a plurality of sensors C11is disposed to detect the size of the lamination sheet S.

A lamination sheet S into which an inner sheet has been inserted is ejected and stacked on a sheet ejection tray104by the third conveyance roller pair113or, for example, a pair of rollers disposed downstream from the third conveyance roller pair113in a sheet conveyance direction. The sheet ejection tray104is disposed inside a housing of the sheet laminator100. Such a configuration facilitates a vertical conveyance of the lamination sheet S toward the sheet ejection tray104.

A conveyance sensor C1is disposed downstream from the first conveyance roller pair107in the sheet conveyance direction to detect the sheet conveyance position of the lamination sheet S.

A conveyance sensor C2is disposed downstream from an entrance roller pair146and upstream from an exit roller pair147in the sheet conveyance direction to detect the sheet conveyance position of the inner sheet P.

The sheet laminator100further includes, for example, a second conveyance roller pair108, a winding roller109serving as a rotary member, a third conveyance roller pair113, a registration roller pair144serving as a first conveyor, a fourth conveyance roller pair145, an ejection roller pair121, and the sheet ejection tray104downstream from the first conveyance roller pair107in the sheet conveyance direction. The sheet laminator10X) further includes separation members116between the winding roller109and the third conveyance roller pair113. The separation members116are movable in the width direction of the two-ply sheet S. Each of the separation members116serves as a separator that separates the lamination sheet S according to the present embodiment.

A conveyance sensor C3is disposed downstream from the second conveyance roller pair108in the sheet conveyance direction to detect the conveyance position of the lamination sheet S and the conveyance position of the inner sheet P.

An abnormal condition detection sensor C4is disposed downstream from the winding roller109in the sheet conveyance direction to detect the condition of the lamination sheet S.

A conveyance sensor C5that detects the conveyance position of the lamination sheet S is disposed downstream from the third conveyance roller pair113in the sheet conveyance direction.

The pickup roller105, the first conveyance roller pair107, the second conveyance roller pair108, and the winding roller109are some examples of a first feeder.

InFIG.1, each set of the second conveyance roller pair108and the third conveyance roller pair113is, for example, a pair of two rollers and is rotationally driven by a drive device (e.g., a motor). The second conveyance roller pair108rotates in one direction. The third conveyance roller pair113rotates in forward and reverse directions, thereby nipping and conveying the lamination sheet S and the inner sheet P.

The second conveyance roller pair108conveys the lamination sheet S and the inner sheet P vertically downward toward the third conveyance roller pair113.

On the other hand, the third conveyance roller pair113can switch the direction of rotation between the forward direction and the reverse direction that is a direction opposite to the forward direction. The third conveyance roller pair113can nip and convey the lamination sheet S vertically downward toward the sheet ejection tray104and also convey the lamination sheet S vertically upward toward the winding roller109in the reverse direction, that is, a direction to pull back the lamination sheet S.

The sheet laminator100is provided with the winding roller109as a rotary member and the separation members116that are disposed between the second conveyance roller pair108and the third conveyance roller pair113. The winding roller109is driven by a drive unit such as a motor to rotate in the forward and reverse directions. The direction of rotation of the winding roller109can be switched between the forward conveyance direction (clockwise direction) and the reverse conveyance direction (counterclockwise direction).

The winding roller10) includes a roller111and a sheet gripper110movably disposed on the roller111to grip the sheet S. The sheet gripper110that is movable grips the leading end of the two-ply sheet S between the sheet gripper110and the roller111. The sheet gripper110may be formed on the outer circumference of the roller111as a single unit or may be formed as a separate unit.

A description is now given of a series of operations performed in the sheet laminator100, with reference toFIG.1. The series of operations performed by the sheet laminator100indicates the operations from separating the lamination sheet S to inserting the inner sheet P into the lamination sheet S.

InFIG.1, multiple lamination sheets S are stacked on the sheet tray102such that a bonded end of each of the multiple lamination sheets S is located downstream from the pickup roller105in the sheet feed direction (sheet conveyance direction). The sheet laminator100picks the lamination sheet S on the sheet tray102by the pickup roller105and conveys the lamination sheet S toward the first conveyance roller pair107.

The lamination sheet S is then conveyed toward the winding roller109by the second conveyance roller pair108disposed downstream from the first conveyance roller pair107in the sheet conveyance direction. In the sheet laminator100, the second conveyance roller pair108conveys the lamination sheet S with the bonded end, which is one of four sides of the lamination sheet S, as a downstream end in the vertical direction (i.e., a vertically downward direction).

Subsequently, when the trailing end of the lamination sheet S in the vertical direction (i.e., the vertically downward direction) passes by the winding roller109, the sheet laminator100temporarily stops the conveyance.

The sheet laminator100then opens the sheet gripper110, reverses the rotation direction of the third conveyance roller pair113, and conveys the lamination sheet S vertically upward toward the opening of the sheet gripper110.

Subsequently, the sheet laminator100stops rotation of the third conveyance roller pair113to stop conveyance of the lamination sheet S when the trailing end of the lamination sheet S is inserted into the opened portion of the sheet gripper110, and closes the sheet gripper110to grip the trailing end of the lamination sheet S. These operations are performed when the lamination sheet S is conveyed by the designated amount.

The sheet laminator100then rotates the winding roller109in the clockwise direction to wind the lamination sheet S around the winding roller109. The lamination sheet S is wound around the winding roller109from the side where the two sheets of the lamination sheet S are overlapped but not bonded.

When the lamination sheet S that is the two-ply sheet is wound around the winding roller109, a winding circumferential length difference (in other words, a winding circumferential amount difference of each of the two sheets of the two-ply sheet) is created between the two sheets in the amount of winding of the lamination sheet S around the circumference of the winding roller109. There is a surplus of the sheet on the inner circumferential side to the center of the winding roller109, which generates a slack toward the bonded end. As a result, a space is created between the two sheets of the lamination sheet S. As the separation members116are inserted into the space generated as described above, from both sides of the two-ply sheet S, the space between the two sheets is reliably maintained. In response to the detection of the leading end of the lamination sheet S with the sheet conveyance sensor C5, the lamination sheet S is conveyed from the sheet conveyance sensor C5by a designated amount to perform these operations.

The sheet laminator100rotates the winding roller109counterclockwise in a state where the separation members116are inserted into the space generated in the lamination sheet S, and moves the space where the lamination sheet S is separated to the trailing end of the lamination sheet S in the vertical direction (i.e., the vertically downward direction inFIG.1). After the winding roller109has been rotated by a designated amount, the sheet laminator100causes the sheet gripper110to open. As a result, the lamination sheet S is separated into the upper and lower sheets at the trailing end.

When the trailing end of the two-ply sheet S is separated into the upper and lower sheets, the sheet laminator100temporarily stops the conveyance of the lamination sheet S and further moves the separation members116in the width direction of the lamination sheet S to separate the whole area of the trailing end of the lamination sheet S. In response to the detection of the leading end of the lamination sheet S with the sheet conveyance sensor C5, the lamination sheet S is conveyed from the sheet conveyance sensor C5by a designated amount to perform these operations.

Subsequently, the sheet laminator100rotates the third conveyance roller pair113counterclockwise to convey the lamination sheet S in the reverse conveyance direction (i.e., vertically upward inFIG.1). A branching member118can be switched at the time when the leading end of the lamination sheet S passes through the conveyance sensor C5. When the lamination sheet S is conveyed to a non-thermal pressure conveyance passage, the branching member118remains at the position illustrated inFIG.8. However, when the lamination sheet S is conveyed to a thermal pressure conveyance passage128toward the thermal pressure roller pair120, the branching member118is switched in the direction toward the thermal pressure conveyance passage128.

The separation members116guide the two sheets separated from the lamination sheet S in the right and left directions inFIG.1, and thus the two sheets are fully separated from each other. Then, the sheet laminator100temporarily stops the conveyance of the lamination sheet S and brings the joined portion of the lamination sheet S into a state of being gripped (nipped) by the third conveyance roller pair113. Accordingly, one end of the lamination sheet S is bonded as the bonded side of the lamination sheet S and the other end of the lamination sheet S is opened largely.

In response to the detection of the leading end of the lamination sheet S with the sheet conveyance sensor C5, the lamination sheet S is conveyed from the sheet conveyance sensor C5by a designated amount to perform these operations.

The sheet laminator100then rotates the second conveyance roller pair108to convey the inner sheet P conveyed from the image forming apparatus side vertically downward toward the third conveyance roller pair113. The image forming apparatus will be described below with reference toFIG.6.

Subsequently, the sheet laminator100rotates the third conveyance roller pair113to merge the lamination sheet S and the inner sheet P, and inserts the inner sheet P into the opened lamination sheet S.

The operation from separation (peeling) of the lamination sheet S to insertion of the inner sheet P has been described above. As illustrated with reference letters SR inFIG.7, the two sheets of the lamination sheet S are separated and conveyed separately in left and right directions respectively.

The sheet laminator100then causes the third conveyance roller pair113to convey the lamination sheet S, in which the inner sheet P has been inserted, downward in the vertical direction. Thus, the two sheets of the lamination sheet S overlap again and the opening of the lamination sheets S is closed. The lamination sheet S in which the inner sheet P has been sandwiched is conveyed to a fixing device having a thermal pressure roller pair120serving as a fuser pressure member by the third conveyance roller pair113or, for example, a pair of rollers disposed downstream from the third conveyance roller pair113in the sheet conveyance direction of the lamination sheet S.

When passing through the thermal pressure roller pair120, the lamination sheet S is thermally pressed and fixed. After passing through the thermal pressure roller pair120, the lamination sheet S continues to be conveyed vertically downward toward the sheet ejection tray104and is stacked on the sheet ejection tray104. Since the lamination sheet S pressed after passing through the thermal pressure roller pair120is ejected vertically downward in this manner, the lamination sheet S can be stacked on the sheet ejection tray104while preventing the heated lamination sheet S from being bent by an external force.

More specifically, in the vertical conveyance according to the present embodiment, the lamination sheet S is ejected vertically downward. Accordingly, the gravity applied to the lamination sheet S is parallel to the tangent line of a fixing nip between the rollers of the thermal pressure roller pair120, and an external force that may deform the lamination sheet S is not applied to the lamination sheet S. Thus, as long as the lamination sheet S continues to be ejected vertically, deformation of the lamination sheet S is reduced. The sheet ejection tray104is disposed after the trailing end of the lamination sheet S passes through the thermal pressure roller pair120and the ejection roller pair121, and the lamination sheet S is cooled before reaching the sheet ejection tray104. Accordingly, the inclination of the stacking surface of the sheet ejection tray104does not apply an external force that may deform the lamination sheet S to the lamination sheet S.

As the lamination sheet S is conveyed vertically downward, the lamination sheet S continues to be conveyed vertically downward until the leading end of the lamination sheet S reaches the thermal pressure roller pair120and the trailing end of the lamination sheet S completely passes through the thermal pressure roller pair120. Accordingly, the vertical conveyance of the lamination sheet S is given, thus preventing the bending of the thermally-pressed lamination sheet S due to the external force.

The sheet laminator100performs a series of operations, in this order, of feeding the lamination sheet S, separating the lamination sheet S, inserting the inner sheet P into the lamination sheet S, and laminating the lamination sheet S with the inner sheet P being inserted, by application of heat and pressure, on a stand-alone basis. This series of operations is carried out automatically without any aid of a user, and therefore the sheet laminator100can enhance and provide the convenience better than a known sheet laminator employing a known technique. Since the sheet laminator100includes the fixing device including the thermal pressure roller pair120and can perform a sheet laminating operation, the sheet laminator100may be referred to as a lamination processing apparatus in a narrow sense. Accordingly, such a lamination processing apparatus is appropriately described as the sheet laminator100below.

FIG.2is an enlarged view of a part of from the thermal pressure roller pair120to the sheet ejection tray104, according to an embodiment of the present disclosure.

In this example, multiple lamination sheets (laminated sheets SG) are stacked on the sheet ejection tray104. As illustrated inFIG.2, a distance L from the fixing nip region of the thermal pressure roller pair120to the stacking surface of the sheet ejection tray104or the uppermost surface of the laminated sheets SG stacked on the sheet ejection tray104on an extension line of a sheet conveyance passage is longer than the length of the lamination sheet S in the sheet conveyance direction. Accordingly, the leading end of the lamination sheet S does not contact the stacking surface of the sheet ejection tray104or the stacked laminated sheets SG until the trailing end of the lamination sheet S completely passes through the thermal pressure roller pair120, thus preventing the heated lamination sheet S from being bent by an external force.

The sheet ejection tray104can stack lamination sheets S up to a thickness of, for example, 50 mm. In order to detect the full state of the stacked laminated sheets SG, an optical sensor160(e.g., a laser displacement meter) that detects the uppermost surface of the stacked laminated sheets SG is provided with the sheet ejection tray104. In this case, the distance L is longer than the length of the lamination sheet S in the sheet conveyance direction at least up to the thickness of 50 mm of laminated sheets SG.

FIG.3is an enlarged view of a part of from the thermal pressure roller pair120to the sheet ejection tray104, according to another embodiment of the present disclosure.

In this example, more sheets (laminated sheets SG) than in the example illustrated inFIG.2are stacked on the sheet ejection tray104. As illustrated inFIG.3, when the leading end of the lamination sheet S during sheet ejection from the ejection roller pair121contacts the uppermost surface of the laminated sheets SG after fixing in the sheet ejection tray104, the lamination sheet S is bent.

The sheet laminator100has a configuration in which a distance D between a contact point of the leading end of the lamination sheet S during sheet ejection and the uppermost surface of the laminated sheets SG and a vertical line passing through the nip region of the ejection roller pair121is equal to or less than 30 mm. For example, an optical sensor160(for example, a laser-displacement meter) is disposed at a position from the sheet ejection tray104such that the optical sensor160detects the distance to the uppermost sheet of the stacked lamination sheets S that is at a position where the distance D is 30 mm. Such a configuration can determine whether the length D is equal to or less than 30 mm.

Setting the distance D to be equal to or less than 30 mm can reduce the bending of the lamination sheet S and enhance the stacking performance, even if the leading end of the lamination sheet S contacts the uppermost surface of the laminated sheets SG during sheet ejection of the lamination sheet S. When the optical sensor160detects that the distance D exceeds 30 mm, the sheet laminator100determines that the sheet ejection tray104is full, and stops fixing and conveying the lamination sheet S. Preventing the distance D from exceeding 30 mm in this manner can prevent the lamination sheet S from being largely bent when the leading end of the lamination sheet S contacts the uppermost surface of the laminated sheets SG during sheet ejection of the lamination sheet S. Note that the numerical value “30 mm” is merely an example, and is a numerical value determined by evaluating in advance the thickness of the lamination sheet S and the inner sheet P to be used depending on the specifications of the sheet laminator.

As illustrated inFIGS.1to3, the ejection roller pair121that ejects the lamination sheet S toward the sheet ejection tray104are disposed downstream from the thermal pressure roller pair120in the sheet conveyance direction. Ejecting the lamination sheet S by the ejection roller pair121can reduce the formation of wrinkles on the lamination sheet S after thermal pressing. Ejecting the lamination sheet S in the vertical direction by the ejection roller pair121can reduce bending of the lamination sheet S after the thermal pressing.

FIG.4is a flowchart of a sheet ejecting operation of the sheet laminator100, according to an embodiment of the present disclosure.

After the start of a thermal pressing operation in the fixing device that includes the thermal pressure roller pair120, the sheet laminator100determines whether the trailing end of the lamination sheet S has passed through the thermal pressure roller pair120, in step S1. For this determination, the sheet laminator100includes a detector (sensor) that detects the lamination sheet S, and the detector is, for example, a conveyance sensor C12(seeFIG.3) disposed downstream from the thermal pressure roller pair120in the sheet conveyance direction of the lamination sheet S.

When the trailing end of the lamination sheet S completely passes through the thermal pressure roller pair120(YES in step S1), the sheet laminator100stops the sheet ejecting operation of the lamination sheet S in step S2, and holds the lamination sheet S by the ejection roller pair121. Then, a timer in the sheet laminator100sets a waiting time T based on the size of the lamination sheet S detected by the sensors C11, in step S3, and a controller90determines whether the waiting time T has elapsed, in step S4. When the waiting time T has not elapsed (NO in step S4), step S4is repeated until the waiting time T elapses. When the waiting time T has elapsed (YES in step S4), the sheet laminator100resumes the sheet ejecting operation of the lamination sheet S in step S5, and ejects the lamination sheet S.

As described above, the sheet laminator100stops the ejection roller pair121, holds the lamination sheet S by the ejection roller pair121, and resumes the sheet ejecting operation after waiting for the waiting time T (required time) to elapse. Accordingly, the lamination sheet S is ejected after waiting for a decrease of the temperature of the thermally-pressed lamination sheet S, thus reducing the bending of the lamination sheet S.

FIG.5is a flowchart of a sheet ejecting operation of the sheet laminator100, according to another embodiment of the present disclosure.

After the start of a thermal pressing operation in the fixing device that includes the thermal pressure roller pair120, the sheet laminator100determines whether the trailing end of the lamination sheet S has passed through the thermal pressure roller pair120, in step S11. For this determination, the sheet laminator100includes a detector (sensor) that detects the lamination sheet S, and the detector is, for example, a conveyance sensor C12(seeFIG.3) disposed downstream from the thermal pressure roller pair120in the sheet conveyance direction of the lamination sheet S.

When the trailing end of the lamination sheet S has not completely passed through the thermal pressure roller pair120(NO in step S11), step S11is repeated until the trailing end of the lamination sheet S completely passes through the thermal pressure roller pair120. When the trailing end of the lamination sheet S has completely passed through the thermal pressure roller pair120(YES in step S11), the sheet laminator100increases the rotation speed of the ejection roller pair121to start increasing the conveyance speed of the ejection roller pair121to convey the lamination sheet S, in step S12. Accordingly, the time during which the leading end of the thermally-pressed lamination sheet S contacts the stacking surface of the sheet ejection tray104or the uppermost surface of the stacked sheets SG is shortened, and thus the bending of the lamination sheet S can be reduced.

FIG.6is a diagram illustrating an overall configuration of an image forming system including an image forming apparatus and the sheet laminator according to an embodiment of the present disclosure.

An image forming system500includes an image forming apparatus300that forms an image on, for example, an inner sheet P, and the sheet laminator100as an external sheet processing apparatus. The sheet laminator100includes a sheet tray102on which lamination sheets S are stacked, and receives inner sheets P fed from the image forming apparatus300to the sheet laminator100via a relay device310. Accordingly, the image forming apparatus300(e.g., a printer or a copier) can insert an inner sheet P on which an image is formed into the lamination sheet S in an in-line system. Thus, the image forming system500can perform a series of operations of, in this order, the feeding of the lamination sheet S, the separation of the lamination sheet S, the insertion of the inner sheet P into the lamination sheet S, and the sheet laminating operation by application of heat and pressure without using manpower.

An operation panel10is disposed in an exterior portion of the image forming apparatus300. The operation panel10serves as a display operation device to display information in the image forming apparatus30) and receives an operation input by a user. In addition, the operation panel10also serves as a notification device that issues a perceptual signal to the user. Alternatively, a notification device other than the operation panel10may be separately disposed in the image forming apparatus300.

FIG.7is a diagram illustrating another overall configuration of an image forming system including a sheet laminator according to another embodiment of the present disclosure, and an image forming apparatus.

The image forming system500includes the image forming apparatus300, the relay device310, the sheet laminator100, and a post-processing apparatus400.

The image forming system500according to the present embodiment feeds an inner sheet P on which an image is formed by the image forming apparatus300from the sheet laminator100via the relay device310. The post-processing apparatus400serving as a post-processing apparatus other than the sheet laminator100is disposed downstream from the sheet laminator100in the sheet conveyance direction. As described above, the post-processing apparatus400that serves as a post-processing apparatus other than the sheet laminator100is disposed downstream from the sheet laminator100in the sheet conveyance direction. By so doing, when a print job that does not require the sheet laminating operation and requires another post-processing operation (e.g., the binding operation or the sheet folding operation) is executed, the image forming system500causes a sheet (i.e., the inner sheet P) conveyed from the image forming apparatus300to be simply passed through the sheet laminator100to convey to the post-processing apparatus400. Accordingly, the post-processing apparatus400can perform the post-processing operation on the sheet (i.e., the inner sheet P). As a result, the image forming system500can be used according to the needs of the user without reducing the efficiency.

As the image forming system500illustrated inFIG.7, the post-processing apparatus400is provided to perform the post-processing operations including the punching operation and the stapling operation, on the lamination sheet S ejected from the image forming apparatus300through the sheet laminator100(in other words, on the lamination sheet S without the sheet laminating operation). In such a case, the lamination sheet S is ejected to an ejection tray150of the post-processing apparatus400after the post-processing operation has been performed on the lamination sheet S.

A detailed description is now given of the sheet laminator100according to an embodiment of the present disclosure.

FIG.8is a diagram illustrating a part of the sheet laminator according to an embodiment of the present disclosure.

The sheet laminator100performs a sheet laminating operation on the lamination sheet S and the inner sheet P that is a sheet medium inserted between two sheets of the lamination sheet S. The sheet laminator100further includes registration roller pair144, a registration guide pair exit guide151, a thermal pressure roller pair120, a first guide148, and a second guide149. The registration roller pair144serves as a first conveyor to send the lamination sheet S from upstream in the sheet conveyance direction toward the thermal pressure roller pair120. The thermal pressure roller pair120serves as a fuser pressure member that heats and presses the lamination sheet S. The first guide148is disposed between the registration roller pair144and the thermal pressure roller pair120to guide the lamination sheet S. The second guide149is disposed facing the first guide148. The sheet laminator100further includes an operation knob153that serves as an operating member with which a user manually rotates the registration roller pair144. When the lamination sheet S is removed at the time of an abnormal stop such as a conveyance jam, the user rotates the operation knob153to rotate the registration roller pair144to bend the jammed sheet S. By so doing, the lamination sheet S is guided to the outside of the sheet conveyance passage between the registration roller pair144and the thermal pressure roller pair120, so that the lamination sheet S is removed. According to this configuration, there is no need to add a guide plate or a conveyance roller pair for removing the lamination sheet S. As a result, the sheet laminator100having a compact, simple configuration is provided. Providing the operation knob153for the sheet jam handling allows the user to rotate the operation knob153to easily remove the lamination sheet S.

Further, inFIG.8, the second guide149is biased toward the first guide148by a torsion spring157serving as a biasing member, and is located at a guide position for guiding the lamination sheet S. Further, a guide detection sensor149ais provided with the second guide149to detect that the second guide149is at an open position that is described below. The guide detection sensor is, for example, a reflection type optical sensor or a transmission type optical sensor. However, the guide detection sensor is not limited to the above-described components and may be a contact type displacement sensor.

FIGS.9A,9B,9C,9D, and9Eare schematic diagrams each illustrating a phase of a flow from occurrence of sheet jam to completion of sheet jam handling.

Specifically,FIG.9Aillustrates a state of occurrence of a sheet jam, in other words, a state where the lamination sheet S is jammed while being nipped by the registration roller pair144and the thermal pressure roller pair120.

FIG.9Bis a schematic diagram illustrating a subsequent phase of the flow from occurrence of sheet jam to completion of sheet jam handling.

FIG.9Cis a schematic diagram illustrating another subsequent phase of the flow from occurrence of sheet jam to completion of sheet jam handling.

FIG.9Dis a schematic diagram illustrating yet another subsequent phase of the flow from occurrence of sheet jam to completion of sheet jam handling.

FIG.9Eis a schematic diagram illustrating yet another subsequent phase of the flow from occurrence of sheet jam to completion of sheet jam handling.

When such a jam as illustrated inFIG.9Aoccurs, the sheet laminator100notifies the user of the occurrence of the sheet jam by an alarm sound or a warning display on the operation panel10to prompt the user to perform a sheet jam handling. InFIG.9B, as the user rotates the operation knob153in a direction indicated by an arrow in the drawing, the lamination sheet S nipped by the registration roller pair144is pushed toward the thermal pressure roller pair120, and the lamination sheet S starts to be bent. As the lamination sheet S is bent, the second guide149also starts rotating around a rotational support155due to the rigidity of the lamination sheet S. and a space between the first guide148and the second guide149starts to increase.

InFIG.9C, as the user continues to rotate the operation knob153, the lamination sheet S further increases the bend. Along with the increase of the bend of the lamination sheet S, the second guide149is completely open, in other words, the second guide149is at the open position at which the sheet conveyance passage is open. Accordingly, the second guide149can move between the guide position and the open position. The second guide149is moved from the guide position to the open position by the lamination sheet S along with guidance of the lamination sheet S to the outside of the sheet conveyance passage. When the guide detection sensor149adetects that the second guide149is at the open position, the controller9X) drives a cam drive motor175that is described below to rotate a movable bracket drive cam173based on the detection result of the guide detection sensor149a. As the movable bracket drive cam173rotates, a movable bracket171that rotatably supports a second thermal pressure roller120brotates clockwise around a movable bracket rotational support171aagainst the biasing force of a biasing spring174. As the second thermal pressure roller120brotates, as illustrated inFIG.9D, a first thermal pressure roller120aand the second thermal pressure roller120bseparate from each other (in other words, the pressure between the first thermal pressure roller120aand the second thermal pressure roller120bare decompressed), the lamination sheet S nipped by the thermal pressure roller pair120is released. Finally, as illustrated inFIG.9E, the user pulls out the lamination sheet S to the right side of the sheet laminator100to remove the lamination sheet S from the sheet laminator100, and thus the jam processing is completed. As described above, bending the lamination sheet S presses and expands the guide with the rigidity of the lamination sheet S to the outside of the sheet conveyance passage. By so doing, the removal operation of the jammed lamination sheet S in the sheet conveyance passage can be easily performed with a simple configuration.

As described above, in the sheet laminator100according to the present embodiment, as illustrated inFIGS.9A to9E, when the lamination sheet S is removed, the user operates the operation knob153to form a bend in the lamination sheet S between the registration roller pair144and the thermal pressure roller pair120and the second guide149biased by the torsion spring157is expanded due to the rigidity of the lamination sheet S. The sheet laminator100according to the present embodiment has the configuration in which the second guide149is expanded. However, the configuration of the sheet laminator is not limited to this configuration. For example, instead of this configuration, the second guide149may be fixed while the first guide148may be biased toward the second guide149by the torsion spring157and rotatable around the rotational support.

A moving mechanism that contacts and separates the rollers of the thermal pressure roller pair120or the rollers of the registration roller pair144is described below with reference toFIGS.12A and12B.

FIGS.10A and10Bare diagrams each illustrating the relative positions of the registration roller pair144and the operation knob153.

The present embodiment illustrated inFIG.10Aindicates the configuration of the operation knob153according to the embodiment illustrated inFIGS.8to9E. The biasing force of the second guide149is generated by the torsion spring157illustrated inFIGS.8to9E. The biasing force is set to about IN to4N, so that the second guide149can be expanded against the biasing force even by the rigidity of the bend of the thinnest passable lamination sheet S and the thickest passable lamination sheet S can be guided to the fixing nip region that is the nip region of two thermal pressure rollers of the thermal pressure roller pair120.

In the embodiment illustrated inFIG.10A, the operation knob153is provided on a shaft144cof a second registration roller144bof the registration roller pair144that is being driven. Moreover, the thermal pressure roller pair120is a pair of rollers that are separatable from each other. On the other hand, in the embodiment illustrated inFIG.10B, a first drive transmission gear159ais disposed on the shaft144cof the second registration roller144b, and a second drive transmission gear159bthat meshes with the first drive transmission gear159ais mounted on a shaft153aof the operation knob153. As a result, as a user rotates the operation knob153, the driving force of the operation knob153is transmitted to the shaft144cof the second registration roller144bvia the first drive transmission gear159aand the second drive transmission gear159bto rotate the second registration roller144b. As described above, the operation knob153may indirectly rotate the second registration roller144bvia the first drive transmission gear159aand the second drive transmission gear159b.

The operation knob153for driving the registration roller pair144is described with reference toFIGS.10A and10B. However, the configuration is not limited to the above-described configuration. Instead of the registration roller pair144, the operation knob153having the similar configuration to the configuration of the registration roller pair144may be provided to the thermal pressure roller pair120. At this time, the registration roller pair144is a pair of rollers that are separatable from each other. In this case, the user rotates the operation knob153so that the lamination sheet S is conveyed in a reverse direction to the sheet conveyance direction to form a bend.

Further, the operation knob153having the similar configuration to the configuration of the registration roller pair144may be provided to both the registration roller pair144and the thermal pressure roller pair120, as shown by operation knob120cinFIG.8.

Further, a one-way clutch may be provided between the operation knob153and the shaft of one roller of the pair of rollers in order to surely form a bend of the lamination sheet S between the registration roller pair144and the thermal pressure roller pair120when the user turns the operation knob153. If the user does not turn the operation knob153so that the lamination sheet S is conveyed in the sheet conveyance direction or the reverse direction opposite to the sheet conveyance direction to form a bend, the operation knob153may idle by the one-way clutch.

In other words, w % ben the operation knob153is provided for the registration roller pair144, the operation knob153can be rotated only in the direction to convey the lamination sheet S toward downstream in the sheet conveyance direction.

On the other hand, when the operation knob153is included in the thermal pressure roller pair120, the operation knob153conveys the lamination sheet S toward upstream in the sheet conveyance direction. For this reason, the operation knob153provided for the thermal pressure roller pair120cannot be turned in the direction in which the lamination sheet S is conveyed toward downstream in the sheet conveyance direction. As a result, this configuration prevents the lamination sheet S from being wound around the thermal pressure roller pair120.

FIGS.11A,11B, and11Care schematic diagrams each illustrating the flow from occurrence of sheet jam to completion of sheet jam handling in a sheet laminator according to different embodiments of the present disclosure.

The sheet laminator100according to the present embodiment has a configuration similar to the configuration of the sheet laminator100illustrated inFIG.8. However, the bend of the lamination sheet S is guided to the gap G of the guide to be taken out to the outside of the sheet conveyance passage, so that the lamination sheet S is removed.

FIG.11Aillustrates occurrence of a sheet jam, in other words, a state where the lamination sheet S is jammed between the registration roller pair144and the thermal pressure roller pair120. The gap G is formed between the registration roller pair144and the second guide149, in particular, between the registration guide pair exit guide151and the second guide149to guide the lamination sheet S to the outside of the sheet conveyance passage. Alternatively, the gap G may be formed between the registration roller pair144and the first guide148, in particular, between the registration guide pair exit guide151and the first guide148, and the lamination sheet S is guided to the gap G, so that the lamination sheet S can be taken out to the outside of the sheet conveyance passage and be removed.

InFIG.11B, as the user rotates the operation knob153in a direction indicated by an arrow in the drawing, the lamination sheet S nipped by the registration roller pair144is pushed toward the thermal pressure roller pair120. By so doing, the lamination sheet S starts to be bent and the bend of the lamination sheet S extends toward the gap G.

Finally, inFIG.11C, the bend of the lamination sheet S comes out form the gap G to the outside of the sheet conveyance passage. Then, the user pulls out the lamination sheet S to the right side of the sheet laminator100to remove the lamination sheet S from the sheet laminator100, and thus the jam processing is completed.

In the present embodiment, the gap G is set to have a length from 7 mm to 9 mm. In addition, as a process in which the lamination sheet S moves to the outside of the sheet conveyance passage, the states after the operation knob153is turned may change toFIGS.11A,11B, and11Cin this order or toFIGS.9A,9B,9C, and11Cin this order.

In the configuration of the embodiment illustrated inFIGS.11A,11B, and11C, the operation knob153is mounted on a shaft144aof the registration roller pair144that is driven (seeFIG.10A). However, in the present embodiment, the operation knob153having the configuration similar to the configuration illustrated inFIGS.11A,11B, and11Cmay be mounted on the thermal pressure roller pair120instead of the registration roller pair144. In this case, the user turns the operation knob153so that the lamination sheet S is conveyed in a reverse direction to the sheet conveyance direction to form a bend. Further, the operation knob153having the similar configuration to the configuration of the registration roller pair144may be provided to both the registration roller pair144and the thermal pressure roller pair120. Further, a one-way clutch may be provided between the operation knob153and the shaft of one roller of the pair of rollers in order to surely form a bend of the lamination sheet S between the registration roller pair144and the thermal pressure roller pair120when the user turns the operation knob153. In other words, in this case, if the user does not turn the operation knob153so that the lamination sheet S is conveyed in the sheet conveyance direction or the reverse direction opposite to the sheet conveyance direction to form a bend, the operation knob153may idle by the one-way clutch.

FIGS.12A and12Bare diagrams each illustrating a moving mechanism170that contacts the rollers of the thermal pressure roller pair120with each other and separates the rollers from each other.

Specifically,FIG.12Aillustrates a contact state of the thermal pressure roller pair120, andFIG.12Billustrates a separation state of the thermal pressure roller pair120.

The moving mechanism170contacts or separates the thermal pressure roller pair120and includes a movable bracket171, a movable bracket drive cam173, and a biasing spring174serving as a biasing member. The thermal pressure roller pair120has the first thermal pressure roller120a(left in the drawings) and the second thermal pressure roller120b(right in the drawings). The first thermal pressure roller120ais fixed. The second thermal pressure roller120bis rotatably supported by a shaft120cat one end of the movable bracket171. The movable bracket171has a bent shape. The shaft120cof the second thermal pressure roller120bof the thermal pressure roller pair120is fixed to one end the movable bracket171. The movable bracket171is disposed to be movable around a movable bracket rotational support171a. Further, the movable bracket171is biased by the biasing spring174to be rotatable in the counterclockwise direction around the movable bracket rotational support171aso that the first thermal pressure roller120aand the second thermal pressure roller120bof the thermal pressure roller pair120contact with each other as illustrated inFIG.12A. The movable bracket drive cam173is rotatable by the cam drive motor175. As the movable bracket drive cam173rotates to the position illustrated inFIG.12B, the movable bracket171to which force is applied by the movable bracket drive cam173rotates in the clockwise direction around the movable bracket rotational support171aagainst the biasing force of the biasing spring174. In response to this operation, the second thermal pressure roller120bthat is movable separates from the first thermal pressure roller120athat is fixed. As a result, the thermal pressure roller pair120is brought into the separation state. Accordingly, by separating the first thermal pressure roller120aand the second thermal pressure roller120bin contact with each other with a relatively large surface pressure, the pulling force of the lamination sheet S can be reduced.

The moving mechanism170illustrated inFIGS.12A and12Bis mounted on the thermal pressure roller pair120. However, a moving mechanism170having the similar configuration as the moving mechanism170on the thermal pressure roller pair120may be mounted on the registration roller pair144. Due to such a configuration, by separating the rollers of the registration roller pair144in contact with each other with a relatively large surface pressure, the pulling force of the lamination sheet S can be reduced.

Further, the rollers of the thermal pressure roller pair120or the rollers of the registration roller pair144may not be separated from each other. For example, one of the rollers of the thermal pressure roller pair120or one of the rollers of the registration roller pair144may have a reduction of pressure or the pulling force of the lamination sheet S may be reduced due to the reduction of pressure.

As described above, the sheet laminator100according to an embodiment of the present disclosure to perform a sheet laminating operation includes the registration roller pair144to convey the lamination sheet S from upstream in the sheet conveyance direction toward the thermal pressure roller pair120, the thermal pressure roller pair120to heat and fix the lamination sheet S, and the guide to guide the lamination sheet S between the registration roller pair144and the thermal pressure roller pair120. When removing the lamination sheet S at the time of an abnormal stop such as a conveyance sheet jam, the user rotates the thermal pressure roller pair120, the registration roller pair144, or both to form a bend on the lamination sheet S. Then, the lamination sheet S is guided to the outside of the sheet conveyance passage between the registration roller pair144and the thermal pressure roller pair120. By so doing, the user can efficiently remove the jammed lamination sheet S.

Aspects of the present invention are, for example, as follows.Aspect 1

In Aspect 1, a sheet laminator includes a fuser pressure member, a conveyor, and a guide. The fuser pressure member thermally fixes a two-ply sheet and a sheet medium inserted between two sheets of the two-ply sheet. The conveyor conveys the two-ply sheet toward the fuser pressure member in a sheet conveyance direction. The guide guides the two-ply sheet in a sheet conveyance passage between the conveyor and the fuser pressure member. At least one of the fuser pressure member or the conveyor is operable to guide the two-ply sheet outside the sheet conveyance passage in response to an occurrence of an abnormal stop of the sheet laminator.Aspect 2

In Aspect 2 of the present disclosure, according to Aspect 1, the sheet laminator further includes an operation part manually rotatable to rotate at least one of the fuser pressure member or the conveyor to guide the two-ply sheet outside the sheet conveyance passage in response to the occurrence of the abnormal stop of the sheet laminator.Aspect 3

In Aspect 3 of the present disclosure, according to Aspect 1 or 2, the guide includes a first guide and a second guide facing the first guide. One of the first guide or the second guide is movable between a guiding position at which the two-ply sheet is guided in the sheet conveyance passage in the sheet conveyance direction and an opening position at which the two-ply sheet is guided outside the sheet conveyance passage. The two-ply sheet moving outside the sheet conveyance passage moves the one of the first guide or the second guide from the guiding position to the opening position.Aspect 4

In Aspect 4, in the sheet laminator according to any one of Aspects 1 to 3, the guide includes a first guide, a second guide facing the first guide, and a gap between the conveyor and an upstream end of one of the first guide or the second guide, the gap guiding the two-ply sheet outside the sheet conveyance passage.Aspect 5

In Aspect 5, in the sheet laminator according to Aspect 2, the conveyor includes the operation part, and the fuser pressure member includes a pair of rollers separatable from each other.Aspect 6

In Aspect 6, in the sheet laminator according to Aspect 2, the fuser pressure member includes the operation part, and the conveyor includes a pair of rollers separatable from each other.Aspect 7

In Aspect 7, in the sheet laminator according to Aspect 5, the operation part includes a one-way clutch and is rotatable only in one direction to convey the two-ply sheet in the sheet conveyance direction.Aspect 8

In Aspect 8, the sheet laminator according to Aspect 6, the operation part in the fuser pressure member includes a one-way clutch and is rotatable only in one direction to convey the two-ply sheet in a direction opposite to the sheet conveyance direction.Aspect 9

In Aspect 9, an image forming system includes the sheet laminator according to any one of Aspect 1 to 8, and an image forming apparatus to form an image on a sheet medium to be fed to the sheet laminator.

The present disclosure is not limited to specific embodiments described above, and numerous additional modifications and variations are possible in light of the teachings within the technical scope of the appended claims. It is therefore to be understood that, the disclosure of this patent specification may be practiced otherwise by those skilled in the art than as specifically described herein, and such, modifications, alternatives are within the technical scope of the appended claims. Such embodiments and variations thereof are included in the scope and gist of the embodiments of the present disclosure and are included in the embodiments described in claims and the equivalent scope thereof.

The effects described in the embodiments of this disclosure are listed as the examples of preferable effects derived from this disclosure, and therefore are not intended to limit to the embodiments of this disclosure.

The embodiments described above are presented as an example to implement this disclosure. The embodiments described above are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, or changes can be made without departing from the gist of the invention. These embodiments and their variations are included in the scope and gist of this disclosure and are included in the scope of the invention recited in the claims and its equivalent.