JP6780418B2 - Image forming device - Google Patents

Description

The present invention relates to an image forming apparatus.

The techniques described in Patent Documents 1 to 4 below are known for an image forming apparatus using a continuous medium.
According to Japanese Patent Application Laid-Open No. 10-123864 as Patent Document 1, when the transport of continuous paper is stopped, the preheater (10) arranged on the upstream side of the fixing device moves in a direction away from the continuous paper, whereby the recording material is recorded. A configuration is described in which the protruding member (15a) of the lifting device (15) protrudes from the preheater (10), and the protruding member (15a) comes into contact with the continuous paper to separate the preheater (10) from the continuous paper. ing.

In Japanese Patent Application Laid-Open No. 07-319303 as Patent Document 2, when an air ejector (8) is installed in the preheater (1) on the upstream side of the heat roll (2) and the print signal is turned off, A technique is described in which compressed air is blown from the air suction port (10) of the preheater (1) onto the back surface of the paper to separate the paper from the preheater (1). In addition, Patent Document 2 also describes a configuration in which the pressure roll (4) is rotated in the reverse direction to loosen the tension of the paper when air is blown.

In Japanese Patent Application Laid-Open No. 2013-167715 as Patent Document 3, when the transport of the continuous paper (P) is stopped, after the holding roll (78) on the downstream side with respect to the preheating device (28) is stopped. , A technique is described in which the continuous paper (P) is separated from the preheating device (28) by stopping the holding roll (62) on the upstream side so that the continuous paper (P) is loosened.
In Japanese Patent Application Laid-Open No. 2006-267769 as Patent Document 4, when the running of the continuous paper (P) is stopped, the lift frame (11) is moved to pressurize the lift frame (11). A technique is described in which the continuous paper (P) is also separated from the heating roll (14b) by separating the roll (14a) from the heating roll (14b).

Japanese Unexamined Patent Publication No. 10-123864 (“0022” to “0028”, FIGS. 2 and 3) Japanese Unexamined Patent Publication No. 07-319303 ("0023" to "0024", "0034" to "0036", FIG. 1) Japanese Unexamined Patent Publication No. 2013-167715 (“0039” to “0060”, FIG. 1) Japanese Unexamined Patent Publication No. 2006-267769 ("0048" to "0052", FIG. 6)

The present invention is one means as compared with the case where there is no means for changing the path of the medium when separating the medium from the heating means on the upstream side of the fixing device or the fixing device when the transport of the medium is stopped. It is a technical issue to reduce the occurrence of thermal deterioration of the medium by separating the medium from the heat source.

In order to solve the technical problem, the image forming apparatus of the invention according to claim 1 is used.
A transfer member that transfers an image onto a continuous medium,
A heating device arranged on the downstream side of the transfer member and in contact with one side of the medium to heat the medium.
A fixing device that is arranged on the downstream side of the heating device and fixes an image transferred onto the medium, and is in contact with a first fixing member that contacts the other surface side of the medium and one surface side of the medium. The fixing device having the second fixing member, and
A transport device arranged on the downstream side of the fixing device and transporting the medium while applying tension to the medium.
A first contact member arranged between the heating device and the fixing device and capable of contacting and detaching the medium, a second contact member capable of contacting and detaching the medium, and the first contact member and the first contact member. A route changing means having a rotating body that supports the contact member of 2 and is rotatable about a center of rotation , and
After the image forming operation is completed, the first fixing member and the second fixing member are separated from each other, and the first contact member and the first contact member and the first contact member and the first contact member are subjected to tension while being conveyed by the transfer device. By changing the state of the contact member of 2, the transport path of the medium is set in the direction opposite to the thickness direction of the medium on the upstream side and the downstream side of the path changing means as compared with the transport path before the change. and control means for moving said medium is controlled so as to change the spaced position away from the contact position in contact with the heating device and the fixing device,
It is characterized by being equipped with.

In order to solve the technical problem, the image forming apparatus of the invention according to claim 2 is used.
A heating device that is arranged on the downstream side of the transfer region where the image is transferred to a continuous medium and that contacts and heats one side of the medium.
With respect to the conveying direction of the medium, the arranged downstream of the heating device, and the first fixing member and the second fixing member is a fixing device for fixing an image of the medium in the fixing area facing the The fixing device having a first fixing member in contact with the other surface side of the medium and a second fixing member in contact with the one surface side of the medium .
A first contact member arranged between the heating device and the fixing device and capable of contacting the medium, a second contact member capable of contacting the medium, the first contact member, and a second contact member. A route changing means having a rotating body that supports a contact member and is rotatable about a center of rotation , and
A first transport member that is arranged upstream of the heating device and transports the medium with respect to the transport direction of the medium, and a first transport member that is arranged downstream of the fixing device and transports the medium while applying tension. A transport device having a second transport member, and
When the transport of the medium is stopped, the transport device is used to transport the medium, the first fixing member and the second fixing member are separated from each other, and the rotating body is rotated to rotate the rotating body before the change. Compared to the transport path, the upstream side and the downstream side of the route changing means are moved in a direction opposite to the thickness direction of the medium, and the first contact member is brought into contact with the medium from the heating device. It is a control means for separating the medium and keeping the posture of the medium entering the fixing region by bringing the second contact member into contact with the medium to a posture corresponding to the posture during transporting the medium. When the transfer of the medium is started, the separation between the heating device and the medium is released while rotating the second transfer member, and the holding of the posture of the medium by the second contact member is released. After that, the control means for bringing the first fixing member into contact with the second fixing member, and the control means.
It is characterized by being equipped with.

The invention according to claim 3 is the image forming apparatus according to claim 1 or 2.
The control is provided with the fixing device having a first fixing member in contact with the surface on which the image of the medium is transferred and a second fixing member facing the first fixing member with the medium sandwiched between them. The means is such that when the second contact member is brought into contact with the medium when the transport of the medium is stopped, the medium is separated from both the first fixing member and the second fixing member. It is characterized by being controlled so as to be arranged in.

The invention according to claim 4 is the image forming apparatus according to claim 3.
When the control means satisfies the condition for stopping the transport of the preset medium, the control means separates the first fixing member from the second fixing member, and then separates the first fixing member and the first contact member and the first fixing member. It is characterized in that the contact member 2 is operated to separate the medium from the heating device and from the first fixing member and the second fixing member, and then control to stop the transport of the medium. To do.

The invention according to claim 5 is the image forming apparatus according to claim 3 or 4.
When the control means resumes the transfer of the medium, after starting the transfer of the medium, the control means releases the separation between the medium and the heating device means, and the medium, the first fixing member, and the second fixing member. The feature is that the first fixing member and the second fixing member are controlled to be brought into contact with each other after the separation from the member is released.

The invention according to claim 6 is the image forming apparatus according to any one of claims 1 to 5.
A rotating body that supports the first contact member and the second contact member and rotates around a center of rotation.
It is characterized by being equipped with.

The invention according to claim 7 is the image forming apparatus according to any one of claims 1 to 6.
Image holder and
A transfer member arranged in the transfer region and transferring an image held by the image holder to a medium,
The control means for separating the transfer member and the image holder when the transport of the medium is stopped, and the control means.
It is characterized by being equipped with.

According to the first aspect of the present invention, there is no means for changing the path of the medium when the medium is separated from the heating means on the upstream side of the fixing device or the fixing device when the transportation of the medium is stopped. In comparison with the above, the medium can be separated from the heat source by one means, and the occurrence of thermal deterioration of the medium can be reduced.
According to the second aspect of the present invention, when the transport of the medium is stopped and the medium is separated from the heating device or the fixing device on the upstream side of the fixing device, there is no means for changing the path of the medium. In comparison, the occurrence of meandering of the medium can be reduced.

According to the third aspect of the present invention, thermal deterioration of the medium can be reduced as compared with the case where the continuous paper comes into contact with the fixing member.
According to the fourth aspect of the present invention, the productivity can be improved as compared with the case where the route changing means is not operated before the transport of the medium is stopped.

According to the fifth aspect of the present invention, productivity can be improved as compared with the case where the route changing means is operated before the start of transporting the medium.
According to the sixth aspect of the present invention, the configuration can be simplified and the manufacturing cost can be reduced as compared with the case where the contact members are individually moved.
According to the invention of claim 7, the habit of the sandwiched portion of the medium is reduced as compared with the case where the continuous paper comes into contact with the transfer member.

FIG. 1 is an overall explanatory view of the image forming apparatus of the first embodiment. FIG. 2 is an explanatory diagram of the route changing means of the first embodiment, FIG. 2A is an explanatory diagram when the image is moved to the image forming position, and FIG. 2B is an explanatory diagram when the route is moved to the transport stop position. FIG. 3 is a perspective view of the route changing means of the first embodiment. FIG. 4 is a block diagram showing each function provided in the control unit of the image forming apparatus of the first embodiment. FIG. 5 is an explanatory diagram of a flowchart of the continuous paper transport control process of the first embodiment.

Next, an embodiment as a specific example of the embodiment of the present invention will be described with reference to the drawings, but the present invention is not limited to the following examples.
In order to facilitate the understanding of the following description, in the drawings, the front-back direction is the X-axis direction, the left-right direction is the Y-axis direction, and the up-down direction is the Z-axis direction, and the arrows X, -X, Y, -Y,. The directions indicated by Z and −Z or the indicated sides are defined as front, rear, right, left, upward, downward, or front, rear, right, left, upper, and lower, respectively.
In addition, in the figure, the one with "・" in "○" means the arrow from the back to the front of the paper, and the one with "×" in "○" is the front of the paper. It shall mean an arrow pointing from to the back.
In the description using the following drawings, illustrations other than the members necessary for the description are omitted as appropriate for the sake of easy understanding.

(Explanation of Overall Configuration of Printer U of Example 1)
FIG. 1 is an overall explanatory view of the image forming apparatus of the first embodiment.
In FIG. 1, the printer U as an example of the image forming apparatus of the first embodiment of the present invention includes a printer main body U1, a feeder unit U2 as an example of a supply device for supplying a medium to the printer main body U1, and an image. It has a recovery unit U3 as an example of a recovery device from which the recorded medium is recovered.

(Explanation of Marking Configuration of Example 1)
In FIG. 1, the main body U1 of the printer is a print image server COM as an example of a control unit C that controls the printer U and an information transmission device connected to the outside of the printer U via a dedicated cable (not shown). It has a communication unit (not shown) for receiving image information transmitted from the printer, a marking unit U1a as an example of an image recording unit for recording an image on a medium, and the like. A personal computer PC as an example of an image transmission device connected to the print image server COM via a wired or wireless communication line and to which information on an image printed by the printer U is transmitted is connected.
The marking portion U1a prints photoconductors Py, Pm, Pc, Pk for each color of Y: yellow, M: magenta, C: cyan, K: black as an example of an image holder, and a photographic image or the like as an example. It has a photoconductor Po for forming an image using a glossy toner that gives gloss to the image in some cases.

In FIG. 1, around the black photoconductor Pk, an example of a charger CCk, an exposure machine ROSk as an example of a latent image forming device, a developer Gk, and a primary transfer device along the rotation direction of the photoconductor Pk. The primary transfer roll T1k as an example and the photoconductor cleaner CLk as an example of a cleaner for an image holder are arranged.
Similarly, around the other photoconductors Py, Pm, Pc, Po, the chargers CCy, CCm, CCc, CCo, the exposure machine ROSy, ROSm, ROSc, ROSo, the developer Gy, Gm, Gc, Go, and the primary transfer. Rolls T1y, T1m, T1c, T1o, and photoconductor cleaners CLy, CLm, CLc, and CLo are arranged.
As an example of the container, a toner cartridge (not shown) containing the developer to be replenished in the developing devices Gy to Go is detachably supported on the upper portion of the marking portion U1a.

Below each of the photoconductors Py to Po, an intermediate transfer belt B, which is an example of an intermediate transfer body and is an example of an image holder, is arranged, and the intermediate transfer belt B is primary with the photoconductors Py to Po. It is sandwiched between the transfer rolls T1y to T1o. The back surface of the intermediate transfer belt B includes a drive roll Rd as an example of a driving member, a tension roll Rt as an example of a tension applying member, a walking roll Rw as an example of a meandering prevention member, and a plurality of driven members as an example. The idler roll Rf, the backup roll T2a as an example of the opposing member for the secondary transfer, the plurality of retract rolls R0 as an example of the movable member, and the primary transfer rolls T1y to T1o.
On the surface of the intermediate transfer belt B, a belt cleaner CLB as an example of a cleaner for the intermediate transfer body is arranged in the vicinity of the drive roll Rd.

On the backup roll T2a, the secondary transfer roll T2b, which is an example of the opposing member, is an example of the transfer member, and is an example of the secondary transfer member, is arranged so as to face each other with the intermediate transfer belt B interposed therebetween. .. The secondary transfer roll T2b of the first embodiment contacts the lower end, which is the center of the winding of the intermediate transfer belt B around the backup roll T2a, at a position shifted to the upstream side in the rotation direction of the intermediate transfer belt B. It is configured as follows. Further, the secondary transfer roll T2b of the first embodiment is pressed against the backup roll T2a by a spring (not shown) as an example of the urging member.

Further, the backup roll T2a is in contact with the contact roll T2c as an example of the contact member in order to apply a voltage to the backup roll T2a having a polarity opposite to the charging polarity of the developer.
The backup roll T2a, the secondary transfer roll T2b, and the contact roll T2c constitute the secondary transfer device T2 of Example 1 as an example of the transfer device, and the primary transfer rolls T1y to T1o, the intermediate transfer belts B, and 2 The transfer devices T1, B, and T2 of the first embodiment are configured by the next transfer device T2 and the like.

In the feeder unit U2, a paper feeding member U2a in which continuous paper S as an example of a continuous medium is wound in a roll shape is rotatably supported. The continuous paper S extending from the paper feed member U2a is sent to the first tension adjusting mechanism U2b. The first tension adjusting mechanism U2b has a guide roll R1 as an example of the guide member. A pair of guide rolls R1 are arranged along the conveying direction of the continuous paper S. A dancer roll R2 as an example of the tension applying member is arranged between the guide rolls R1. The dancer roll R2 is in contact with the surface of the continuous paper S and is supported in a state where it can be raised and lowered freely. Therefore, the dancer roll R2 applies tension to the continuous paper S by its own weight of the dancer roll R2. The paper feed member U2a of the first embodiment feeds out the continuous paper S when the height of the dancer roll R2 becomes higher than the preset feed height, and the height of the dancer roll R2 is higher than the preset stop height. When it becomes low, the rotation is controlled so as to stop the feeding of the continuous paper S.

A paper feeding mechanism U2c as an example of the continuous paper S transport device is arranged on the downstream side of the first tension adjusting device U2b with respect to the transport direction of the continuous paper S. The paper feeding mechanism U2c has a plurality of guide rolls R3 as an example of the guide member. On the downstream side of the guide roll R3, a paper feed roll R4 is arranged as an example of a first transport member, an example of a drive member, and an example of a paper feed member. On the paper feed roll R4, a sandwiching roll R5 as an example of the facing member is arranged so as to sandwich the continuous paper S. The paper feed roll R4 feeds the continuous paper S at a preset transport speed of the continuous paper S. The sandwiching roll R5 sandwiches the continuous paper S between the paper feed roll R4 and the continuous paper S at a preset pressure in order to reduce the occurrence of slippage between the paper feed roll R4 and the continuous paper S. Further, in the guide roll R3, in order to reduce the occurrence of slippage between the paper feed roll R4 and the continuous paper S, the continuous paper S so that the area around which the continuous paper S is wound around the paper feed roll R4 becomes large. It guides the route of.

The continuous paper S sent out from the paper feeding mechanism U2c is sandwiched between the transport rolls Ra as an example of the transport members arranged at the inlet of the main body U1 of the printer. A plurality of guide rolls Rb are arranged on the right side of the transport roll Ra as an example of the guide member. The guide roll Rb of the first embodiment is configured in a rotatable roll shape.
An idler roll R6 as an example of the guide member is arranged on the downstream side of the continuous paper S in the transport direction with respect to the secondary transfer roll T2b. The idler roll R6 is arranged so as to contact the lower surface of the continuous paper S, that is, the surface opposite to the surface on which the image is transferred. The idler roll R6 is configured to be rotatable while supporting the continuous paper S.

On the downstream side of the idler roll R6, a preheating plate PH, which is an example of a heating device and is an example of a preheating device, is arranged. The preheating plate PH of Example 1 is arranged on the lower surface side of the continuous paper S. Further, the preheating plate PH is formed in a curved surface shape whose upper surface has a curvature. The preheating plate PH of Example 1 is, for example, an aluminum alloy plate having a radius of curvature of 2400 mm, a thickness of 5 mm, a width of 500 mm, and a length of 300 mm, and has a 3000 W rubber heater as an example of a heat source on the surface. It is pasted. The preheating plate PH is controlled to reach a preset heating temperature by a temperature control means (not shown).
A fixing device F is arranged on the downstream side of the preheating plate PH. The fixing device F is an example of a first fixing member, a heating roll Fh as an example of a heating member, and a position example of a second fixing member, a pressure roll Fp as an example of a pressure member. And have. A heater h as an example of a heat source is housed inside the heating roll Fh.

A guide roll Rb as an example of the guide member is rotatably supported on the downstream side of the fixing device F. A recovery unit U3 is arranged on the downstream side of the guide roll Rb. The recovery unit U3 has a discharge mechanism U3a. The discharge mechanism U3a is an example of a second transport member, and a pull roll R11 as an example of a drive member and a discharge member is arranged. On the pull roll R11, a sandwiching roll R12 as an example of the opposing member is arranged so as to sandwich the continuous paper S. The pull roll R11 conveys the continuous paper S to the downstream side at a preset transfer speed. The sandwiching roll R12 sandwiches the continuous paper S between the pull roll R11 and the continuous paper S at a preset pressure in order to reduce the occurrence of slippage between the pull roll R11 and the continuous paper S. A guide roll R13 as an example of the guide member is arranged on the downstream side of the sandwiching roll R12 with respect to the conveying direction of the continuous paper S. Further, the guide roll R13 guides the path of the continuous paper S so that the area around which the continuous paper S is wrapped around the pull roll R11 becomes large in order to reduce the occurrence of slippage between the pull roll R11 and the continuous paper S. doing.

A second tension adjusting mechanism U3b is arranged on the downstream side of the discharging mechanism U3 with respect to the conveying direction of the continuous paper S. The second tension adjusting mechanism U3b is configured in the same manner as the first tension adjusting mechanism U2b. Therefore, it has a pair of guide rolls R14 and a dancer roll R15.
A take-up roll U3c as an example of the recovery member is arranged on the downstream side of the second tension adjusting mechanism U3b with respect to the conveying direction of the continuous paper S. The take-up roll U3c winds the continuous paper S. The take-up roll U3c winds up the continuous paper S when the height of the dancer roll R15 is lower than the preset take-up height, and when the height of the dancer roll R15 becomes higher than the preset stop height. Stop winding the continuous paper S.

(Marking operation)
When the printer U receives the image information transmitted from the personal computer PC via the print image server COM, a job which is an image forming operation is started. When the job is started, the photoconductors Py to Po, the intermediate transfer belt B, and the like rotate.
The photoconductors Py to Po are rotationally driven by a drive source (not shown).
A preset voltage is applied to the chargers CCy to CCo to charge the surfaces of the photoconductors Py to Po.
The exposure machines ROSy to ROSo output laser light Ly, Lm, Lc, Lk, Lo as an example of light for writing a latent image in response to a control signal from the control unit C, and charge the photoconductors Py to Po. An electrostatic latent image is written on the surface.
The developing devices Gy to Go develop an electrostatic latent image on the surface of the photoconductors Py to Po into a visible image.
When the developer is consumed during development in the developing devices Gy to Go, the developing agent is replenished from a toner cartridge (not shown).

A primary transfer voltage having a polarity opposite to the charging polarity of the developer is applied to the primary transfer rolls T1y to T1o, and the visible image of the surface of the photoconductors Py to Po is transferred to the surface of the intermediate transfer belt B.
The photoconductor cleaners CLy to CLo are cleaned by removing the developer remaining on the surface of the photoconductors Py to Po after the primary transfer.
When the intermediate transfer belt B passes through the primary transfer region facing the photoconductors Py to Po, images are transferred and laminated in the order of O, Y, M, C, and K, and the intermediate transfer belt B faces the secondary transfer device T2. Passes through the secondary transfer region Q4. In the case of a monochromatic image, an image of only one color is transferred and sent to the secondary transfer region Q4.

The transport roll Ra transports the continuous paper S extending from the feeder unit U2 to the downstream side. The guide roll Rb guides the continuous paper S to the secondary transfer region Q4.
In the secondary transfer device T2, a secondary transfer voltage having the same polarity as the charging polarity of the developer set in advance is applied to the backup roll T2a via the contact roll T2c, and the image of the intermediate transfer belt B is transferred to the continuous paper S. To do.
The preheating plate PH heats the continuous paper S in the secondary transfer region Q4 to give heat to melt the unfixed developer.
The fixing device F heats the continuous paper S passing through the fixing region Q5 where the heating roll Fh and the pressure roll Fp come into contact with each other while pressurizing the continuous paper S to fix the unfixed image on the surface of the continuous paper S.
The collection unit U3 winds up the continuous paper S on which the image is fixed.

(Explanation of route change means)
FIG. 2 is an explanatory diagram of the route changing means of the first embodiment, FIG. 2A is an explanatory diagram when the image is moved to the image forming position, and FIG. 2B is an explanatory diagram when the route is moved to the transport stop position.
FIG. 3 is a perspective view of the route changing means of the first embodiment.
In FIGS. 1 and 2, a route changing means 1 is arranged between the preheating plate PH and the fixing device F. In FIGS. 2 and 3, the route changing means 1 is
It has a rotating arm 2 as an example of a rotating body. A pair of front and rear rotating arms 2 are arranged. The rotary arm 2 is rotatably supported by the printer main body U1 about a rotation center 2a. The rotating arm 2 has a first arm portion 2b extending in the radial direction from the rotation center 2a, and a second arm portion 2c extending in a direction substantially 90 ° out of phase with respect to the first arm portion 2a. Therefore, the rotary arm 2 of the first embodiment is formed in an L shape.

A first holding roll 3 as an example of the first contact member is rotatably supported on the first arm portion 2b. Further, a second holding roll 4 as an example of the second contact member is rotatably supported on the second arm portion 2c.
A driven gear 6 as an example of a driven member to be driven is supported on the rotary arm 2 coaxially with the rotation center 2a. A drive gear 7 as an example of a drive transmission member meshes with the driven gear 6. Drive is transmitted to the drive gear 7 from a motor 8 as an example of a drive source. The motor 8 of the first embodiment is composed of a motor capable of forward and reverse rotation.

Therefore, in the route changing means 1 of the first embodiment, at the image forming position shown in FIG. 2A, the first holding roll 3 is located below the continuous paper S, and the second holding roll 4 is located above the continuous paper S. .. Therefore, all of the holding rolls 3 and 4 are held in a state of being separated from the surface of the continuous paper S.
Then, when the motor 8 rotates and moves to the transport stop position shown in FIG. 2B, the first holding roll 3 comes into contact with the lower surface of the continuous paper S to lift the continuous paper S upward, and the second holding roll 4 continuously moves. It comes into contact with the upper surface of the paper S and pushes down the continuous paper S downward. At this time, as shown in FIG. 2B, the continuous paper S separates from the preheating plate PH as the first holding roll 3 rises. Further, the continuous paper S is held at a posture corresponding to the posture at the image forming position, that is, the posture of the continuous paper S with respect to the fixing device F and the approach angle with respect to the fixing region Q5 as the second holding roll 3 is lowered. ..
In the first embodiment, when the transport of the continuous paper S is stopped at the end of the job or when a failure occurs, the continuous paper S is moved to the transport stop position and is moved to the image forming position when the job is executed.

(Explanation of fixing device F)
The fixing device F of the first embodiment is an example of the first conveying member, and the heating roll Fh as an example of the first fixing member and the pressure roll Fp as an example of the second fixing member are It is configured so that it can be contacted and separated. In the fixing device F of the first embodiment, the contact position where the pressure roll Fp contacts the heating roll Fh as shown by the solid line in FIG. 1 and the pressure roll Fp are separated from the heating roll Fh as shown by the broken line in FIG. The pressure roll Fp can be moved to and from the separated position.
The configuration for contacting and separating the heating roll Fh and the pressure roll Fp is, for example, applying the mechanism for changing the pressure in the fixing region described in Japanese Patent Application Laid-Open No. 2008-185638 to the mechanism for contacting and separating. Various conventionally known configurations such as the techniques described in JP-A-2015-25920 can be adopted. Therefore, the mechanism for contacting and separating the heating roll Fh and the pressure roll Fp will not be illustrated or described in detail.

Further, the secondary transfer roll T2b of the first embodiment is also configured to be able to contact and separate from the intermediate transfer belt B in the same manner as the pressure roll Fp.
In Example 1, the pressurizing roll Fp and the secondary transfer roll Fp of the fixing device F are in contact with the heating roll Fh and the intermediate transfer belt B, respectively, when the job is executed, and when the continuous paper S is stopped, the heating roll Fh and Separated from the intermediate transfer belt B.

(Explanation of pull roll R11)
In the pull roll R11 as an example of the second transport member of the first embodiment, a torque limiter TL as an example of the drive limiting member is arranged in the drive transmission system from the drive motor M6 of the pull roll as an example of the drive source. There is. The torque limiter TL applies the pull roll R11 to the pull roll R11 when the load acting on the pull roll R11 reaches a preset load as the tension of the continuous paper S increases when the pull roll R11 conveys the continuous paper S. Limit drive transmission. That is, when the load of the pull roll R11 does not reach the preset load, the torque limiter TL does not operate, and the drive of the pull roll drive motor M6 is transmitted to the pull roll R11. The rotation speed of the drive motor M6 of the pull roll R11 is such that when the torque limiter TL does not operate, the peripheral speed of the pull roll R11 is the paper feed roll R4 so that tension is reliably applied to the continuous paper S during transportation of the continuous paper S. It is set to be 10% faster than the peripheral speed of. Further, as the torque limiter TL, a commercially available torque controller is adopted, and the set torque can be changed according to the type of continuous paper S to be conveyed.

(Explanation of Control Unit of Example 1)
FIG. 4 is a block diagram showing each function provided in the control unit of the image forming apparatus of the first embodiment.
In FIG. 4, the control unit C of the printer U as an example of the control means has an input / output interface I / O for inputting / outputting signals to / from the outside. Further, the control unit C has a ROM: read-only memory in which a program, information, and the like for performing necessary processing are stored. Further, the control unit C has a RAM: random access memory for temporarily storing necessary data. Further, the control unit C has a CPU: a central processing unit that performs processing according to a program stored in a ROM or the like. Therefore, the control unit C of the first embodiment is composed of a small information processing device, a so-called microcomputer. Therefore, the control unit C can realize various functions by executing the program stored in the ROM or the like.

(Signal output element connected to control unit C)
The control unit C is input with an output signal from a signal output element such as an operation unit UI or a sensor (not shown).
The operation unit UI has an input button UIa for inputting an arrow, a numeric keypad, or the like as an example of an input member. Further, the operation unit UI includes a display unit UIb or the like as an example of the notification member.

(Controlled element connected to control unit C)
The control unit C includes a drive circuit D1 of the main drive source, a drive circuit D2 of a contact separation motor for fixing, a drive circuit D3 of a contact separation motor for transfer, a drive circuit D4 of a motor for changing a route, and a paper feed roll. It is connected to a drive circuit D5, a pull-roll drive circuit D6, a power supply circuit E, and other control elements (not shown). The control unit C outputs the control signals to the circuits D1 to D6, E and the like.
D1: Drive circuit of the main drive source The drive circuit D1 of the main drive source is an example of the drive source of the image holder, and the photoconductors Py to Po and the intermediate through the main motor M1 as an example of the main drive source. The transfer belt B or the like is rotationally driven.

D2: Drive circuit of the contact separation motor for fixing The drive circuit D2 of the contact separation motor for fixing drives the contact separation motor M2 for fixing to contact the pressurizing roll Fp with the heating roll Fh, or Separate.
D3: Drive circuit of the contact separation motor for transfer The drive circuit D3 of the contact separation motor for transfer drives the contact separation motor M3 for transfer to contact the secondary transfer roll T2b with respect to the continuous paper S, or , Separate.
D4: Drive circuit of the motor for changing the route The drive circuit D4 of the motor for changing the route drives the motor 8 of the route changing means 1 and puts the holding rolls 3 and 4 between the image forming position and the transport stop position. Move with.

D5: Drive circuit of the paper feed roll The drive circuit D5 of the paper feed roll drives the drive motor M5 of the paper feed roll to rotate the paper feed roll R4.
D6: Pull-roll drive circuit The pull-roll drive circuit D6 drives the pull-roll drive motor M6 to rotate the pull-roll R11 via the torque limiter TL.

E: Power supply circuit The power supply circuit E includes a power supply circuit Ea for development, a power supply circuit Eb for charging, a power supply circuit Ec for transfer, a power supply circuit Ed for fixing, and the like.
Ea: Power supply circuit for development The power supply circuit Ea for development applies a development voltage to the development rolls of the developers Gy to Go.
Eb: Power supply circuit for charging The power supply circuit Eb for charging applies a charging voltage for charging the surfaces of the photoconductors Py to Po to each of the chargers CCy to CCo.

Ec: Power supply circuit for transfer The power supply circuit Ec for transfer applies a transfer voltage to the primary transfer rolls T1y to T1o and the contact roll T2c.
Ed: Power supply circuit for fixing The power supply circuit Ed for fixing supplies electric power to the built-in heater of the heating roll Fh of the fixing device F.

(Function of control unit C)
The control unit C has a function of executing processing according to an input signal from the signal output element and outputting a control signal to each of the control elements. That is, the control unit C has the following functions.
C1: Image formation control means The image formation control means C1 controls the drive of each member of the printer U, the application timing of each voltage, and the like according to the image information input from the print image server COM, and forms an image. Controls the execution, termination, and interruption of jobs that are operations.
C2: Power supply circuit control means The power supply circuit control means C2 controls the power supply circuits Ea to Ed to control the voltage applied to each member and the electric power supplied to each member.

C3: Transfer control means The transfer control means C3 controls the transfer of the continuous paper S via the paper feed roll drive circuit D5 and the pull roll drive circuit D6. In FIG. 5, the transfer control means C3 of the first embodiment drives the pull roll R11 when the job is started, and drives the paper feed roll R4 at the timing when the secondary transfer roll T2b and the pressure roll Fp come into contact with each other. Control to let. Further, when the transfer of the continuous paper S is stopped due to the end of the job or the like, after the pull roll R11 is stopped, the paper feed roll R4 is stopped as the holding rolls 3 and 4 move to the transfer stop position. Control to let.

C4: Contact / separation control means The contact / separation control means C4 includes a contact / separation control means C4A for the secondary transfer roll and a contact / separation control means C4B for the pressure roll. The contact / separation control means C4 moves the secondary transfer roll T2b and the pressure roll Fp to the contact position and the separation position at the start and end of the job.
C4A: Control means for controlling contact / separation of the secondary transfer roll The means for controlling contact / separation of the secondary transfer roll C4A sets the secondary transfer roll T2b as the contact position via the drive circuit D3 of the contact separation motor for transfer. Move to and from the distance position. The control means C4A for controlling the contact / separation of the secondary transfer rolls of the first embodiment moves the secondary transfer rolls T2b toward the contact position after the holding rolls 3 and 4 have moved to the image forming position at the start of the job. Further, the control means C4A for controlling the contact / separation of the secondary transfer rolls of the first embodiment controls to move the secondary transfer roll T2b to the separation position when the image passes through the fixing region Q5 at the end of the job. To do. Further, when the transport of the continuous paper S is stopped due to a failure or the like, the secondary transfer roll T2b is promptly moved to the separated position.

C4B: Control means for controlling contact / separation of the pressure roll The control means C4B for controlling the contact / separation of the pressure roll is to transfer the pressure roll Fp to the heating roll Fh or continuously via the drive circuit D2 of the contact separation motor for fixing. The paper S is brought into contact with and separated from the paper S. The pressure roll contact / separation control means C4B of the first embodiment performs contact / separation of the pressure roll Fp in time with the contact / separation of the secondary transfer roll T2b.

C5: Control means of the route changing means The control means C5 of the route changing means sets the route changing means 1 to the transport stop position as an example of the first position and the first position via the drive circuit D4 of the motor for attitude control. It is moved to and from the image forming position as an example of the position 2. At the start of the job, the control means C5 of the route changing means of the first embodiment moves from the transport stop position to the image forming position in accordance with the start of driving the pull roll R11. Further, when the transfer of the continuous paper S is stopped at the end of the job or the like, the control means C5 of the route changing means of the first embodiment moves from the image forming position to the transfer stop position after the secondary transfer rolls T2b and the like are separated. Let me.
During the operation of the route changing means 1, the path length of the continuous paper S changes continuously, but even in that case, the operation of the route changing means 1 is performed so that the continuous paper S does not loosen or tear. You need to set the speed. That is, when the route changing means 1 is moved from the image forming position to the transport stop position, the route length gradually increases, but the increasing speed of the route length does not exceed the peripheral speed of the paper feed roll R4. The operating speed of the changing means 1 is set. Further, when the route changing means 1 is moved from the transport stop position to the image forming position, the route length is gradually shortened, but the reduction speed of the route length exceeds the peripheral speed difference between the pull roll R11 and the paper feed roll R4. The operating speed of the route changing means 1 is set so as not to occur. By doing so, the tension acting on the continuous paper S is always kept constant.

(Explanation of Flow Diagram of Example 1)
Next, the flow of control in the printer U of the first embodiment will be described using a flow chart, a so-called flowchart.

(Explanation of the flowchart of the continuous paper transport control process)
FIG. 5 is an explanatory diagram of a flowchart of the continuous paper transport control process of the first embodiment.
The processing of each step ST in the flowchart of FIG. 5 is performed according to the program stored in the control unit C of the printer U. Further, this process is executed in parallel with various other processes of the printer U.
The flowchart shown in FIG. 5 is started by turning on the power of the printer U.

In ST1 of FIG. 5, it is determined whether or not the job has been started. If yes (Y), proceed to ST2, and if no (N), repeat ST1.
In ST2, the rotation of the pull roll R11 is started. Then, proceed to ST3.
In ST3, the holding rolls 3 and 4 are moved to the image forming position. Then, proceed to ST4.
In ST4, the continuous paper S is started to be conveyed by the paper feed roll R4. Then, proceed to ST5.

In ST5, the following processes (1) and (2) are executed to proceed to ST6.
(1) The secondary transfer roll T2b is moved to the contact position.
(2) The pressure roll Fp is moved to the contact position.
In ST6, it is determined whether or not the transport of the continuous paper S has been stopped. If yes (Y), proceed to ST7, and if no (N), proceed to ST12.
In ST7, the following processes (1) and (2) are executed to proceed to ST8.
(1) The secondary transfer roll T2b is moved to a separated position.
(2) The pressure roll Fp is moved to a separated position.

In ST8, the holding rolls 3 and 4 are moved to the transport stop position. Then, proceed to ST9.
In ST9, the rotation of the paper feed roll R4 is stopped. Then, the process proceeds to ST10.
In ST10, the drive of the pull roll R11 is stopped. Then, the process proceeds to ST11.
In ST11, it is determined whether or not the transport of the continuous paper S is restarted. If yes (Y), proceed to ST2, and if no (N), repeat ST11.

In ST12, it is determined whether or not the job has been completed. If yes (Y), proceed to ST13, and if no (N), return to ST6.
In ST13, the following processes (1) and (2) are executed to proceed to ST14.
(1) The secondary transfer roll T2b is moved to a separated position.
(2) The pressure roll Fp is moved to a separated position.

In ST14, the holding rolls 3 and 4 are moved to the transport stop position. Then, proceed to ST15.
In ST15, the rotation of the paper feed roll R4 is stopped. Then, the process proceeds to ST16.
In ST16, the drive of the pull roll R11 is stopped. Then, it returns to ST1.

(Action of Example 1)
In the printer U of the first embodiment having the above configuration, the secondary transfer roll T2 and the pressure roll Fp are moved to separate positions before the job is started. Further, the route changing means 1 has moved to the transport stop position. Therefore, the continuous paper S is separated from the preheating plate PH and the fixing rolls Fh and Fp, and the approaching posture to the fixing region Q5 is held by the second holding roll 4. Therefore, the continuous paper S in which the transfer is stopped receives pressure in the secondary transfer region Q4 and the fixing region Q5 to form a habit, or receives heat from the heated heating roll Fh to be thermally deformed. Damage is reduced.

When the job is started, the drive of the pull roll R11 is started. Then, the route changing means 1 moves from the transport stop position to the image forming position, and the paper feed roll R4 is also driven. At this time, the movement of the route changing means 1 and the driving of the paper feed roll R4 may be simultaneous or back and forth. Further, the secondary transfer roll T2b and the pressure roll Fp move to the contact position, and the image forming operation is started.
Then, when the image forming operation is stopped, such as when the job is completed, the secondary transfer roll T2b and the pressure roll Fp are separated from each other. Then, after the route changing means 1 moves to the transport stop position, the paper feed roll R4 is stopped, and the drive of the pull roll R11 is stopped.

When the route changing means 1 moves from the transport stop position to the image formation position at the start of the job, the route change means 1 stops transporting the path length of the continuous paper S between the secondary transfer region Q4 and the fixing region Q5. The image formation position is shorter than that of the position. Therefore, when the route changing means 1 moves to the image forming position while the pull roll R11 is not driven, the continuous paper S loosens. If the continuous paper S is sandwiched between the secondary transfer roll T2b or the pressure roll Fp in a loosened state, the continuous paper S may be sandwiched in a state deviated from a preset position. Therefore, if the continuous paper S is sandwiched in a misaligned state, the continuous paper S may be wavy, fluttered, or wrinkled. Further, if the transport is started in a state where the continuous paper S is misaligned, the continuous paper S may be skewed, offset, or meandered. Further, the loose continuous paper S may be brought into close contact with the intermediate transfer belt B and dragged, so that the continuous paper S may be broken. Therefore, transfer defects in the secondary transfer region Q4, heating unevenness in the preheating plate PH, and fixing defects in the fixing device F may occur, and image quality defects such as register misalignment and image loss may occur.

Similarly, in the configurations described in Patent Documents 2 and 4, when the continuous paper is sandwiched by the fixing device at the time of restarting the transfer, the continuous paper S may be wavy or meandering. In particular, in the configurations described in Patent Documents 2 and 4, there is a problem that the configuration in which the continuous papers S are separated is large and the manufacturing cost increases. Further, in a large-scale configuration, there is a problem that quick operation is difficult, movement takes time, and the number of prints per unit time: productivity is lowered.
Further, also in the configuration described in Patent Document 3, the continuous paper S is started to be conveyed from the state where the continuous paper S is loosened, and when the loose continuous paper is sandwiched between the conveying members at the start of the conveying, wrinkles and wrinkles are generated. It may occur. Further, in the configuration described in Patent Document 1, a pin in contact with the continuous paper S is housed in the preheater at the time of image formation, and the pin itself is in a heated state. Therefore, the portion in contact with the pin may be heated pinpointly, resulting in image quality defects. Further, in the configuration described in Patent Document 1, the preheater itself is moved, and there is a problem that the configuration in which the preheater is moved while being heated becomes large-scale. Therefore, as in the case of the above-mentioned Patent Documents 2 and 4, there is also a problem of an increase in cost and a decrease in productivity.

On the other hand, in the first embodiment, at the end of the image forming operation, the continuous paper S is moved after the route changing means 1 is moved while applying tension to the continuous paper S with the pull roll R11 before the continuous paper S is stopped. Since it is stopped, the continuous paper S is held in a stretched state by the holding rolls 3 and 4 instead of being loosened. Therefore, it is possible to reliably prevent the continuous paper S from coming into contact with the heating member PH, the first fixing member Fh, and the second fixing member Fp and thermally deteriorating. Then, when the continuous paper S is started to be conveyed at the start of the job or the transfer, the paper feed roll R4 is driven while the pull roll R11 similarly applies tension to the continuous paper S to convey the continuous paper S. Since the route changing means 1 is moved to return the continuous paper S to the transport path, there is no change in the position of the continuous paper S in the roll axis direction, so that waviness, wrinkles, meandering, etc. do not occur as compared with the conventional technique. , The wasted length of the continuous paper S is reduced, and the productivity is improved. In addition, the device configuration is simpler and smaller than the conventional technology, and the cost can be reduced.

Further, the route changing means 1 is arranged between the preheating plate PH and the fixing device F, and unlike Patent Document 1, the temperature rise of the route changing means 1 is reduced. Therefore, even if the holding rolls 3 and 4 come into contact with the continuous paper S, the image quality defect in the continuous paper S is reduced.
When the path changing means 1 moves while being pulled by the pull roll R11, if the tension acting on the continuous paper S becomes large, the torque limiter operates to reduce the tension of the continuous paper S becoming excessive. Therefore, the occurrence of problems such as tearing of the continuous paper S is suppressed.
Further, in the first embodiment, the movement of the route changing means 1 is performed during the transportation of the continuous paper S, and the decrease in productivity is prevented as compared with the case where the movement is not performed during the transportation.

(Change example)
Although the examples of the present invention have been described in detail above, the present invention is not limited to the above examples, and various modifications are made within the scope of the gist of the present invention described in the claims. It is possible. Examples of modifications (H01) to (H09) of the present invention are illustrated below.
(H01) In the above embodiment, the printer U as an example of the image forming apparatus has been illustrated, but the present invention is not limited to this, and the printer U is composed of, for example, a copying machine, a fax machine, or a multifunction device having a plurality or all of these functions. It is also possible to do.

(H02) In the above embodiment, a configuration in which a four-color developer is used as the printer U has been illustrated, but the present invention is not limited to this, and for example, a monochromatic image forming apparatus or a three-color or less or five-color or more color is used. It can also be applied to a multicolor image forming apparatus.
(H03) In the above-described embodiment, a roll-shaped secondary transfer roll T2b has been illustrated as an example of the transfer member, but the present invention is not limited thereto. For example, it is also possible to use a so-called transfer belt in which a belt is stretched on the transfer roll side as well. Similarly, a belt-shaped intermediate transfer belt B has been illustrated as an example of the image holder, but the present invention is not limited thereto. It is also possible to use a drum-shaped intermediate transfer body. Further, the monochromatic image forming apparatus does not have an intermediate transfer body, and the transfer roll can come into contact with and separate from the photoconductor as an example of the image holder, and is also applicable to such an image forming apparatus. It is possible. When a drum-shaped photoconductor or an intermediate transfer body is used, the opposing members facing each other across the medium in the transfer region are a combination of the photoconductor and the transfer roll, or the intermediate transfer body and the transfer roll.

(H04) In the above embodiment, the preheating plate PH has been illustrated as an example of the heating device, but the present invention is not limited to this. It is also possible to use a roll-shaped preheating member. Further, although it is desirable that the image is in contact with the surface opposite to the image recording surface, it is also possible to dispose of the image in contact with or in contact with the image recording surface side.
(H05) In the above-described embodiment, roll-shaped holding rolls 3 and 4 are exemplified as the first contact member and the second contact member, but the present invention is not limited thereto. For example, a pad-shaped or rod-shaped member having high slidability can be used.

(H06) In the above embodiment, the route changing means 1 illustrates a configuration in which the two holding rolls 3 and 4 are moved by the rotating arm 2, but the present invention is not limited to this. For example, the holding rolls 3 and 4 may be moved by separate members.
(H07) In the above embodiment, it is desirable, but not limited to, to move the pressure roll Fp in conjunction with the secondary transfer roll T2b. The secondary transfer roll T2b may be configured not to be separated. It is also possible to shift the timing.

(H08) In the above embodiment, a configuration in which the torque limiter TL is provided on the pull roll R11 has been illustrated, but the present invention is not limited to this. For example, it is possible to provide a sensor for detecting the tension of the continuous paper S and control the transmission of the drive by turning on / off the electromagnetic clutch. Alternatively, tension can be applied using a dancer roll. Further, it is also possible to provide the heating roll Fh, the secondary transfer roll T2b, and the paper feed roll R4 with a structure such as a torque limiter TL or a one-way clutch that allows idling.
(H09) In the above embodiment, the configuration adopted in the dry electrophotographic image forming apparatus has been illustrated, but the present invention is not limited thereto. For example, it can be adopted in a wet electrophotographic type image forming apparatus or an inkjet type image forming apparatus.

1 ... Route changing means,
2 ... Rotating body,
2a ... Center of rotation,
3 ... First contact member,
4 ... Second contact member,
B ... Image holder,
C ... Control means,
F ... Fixing device,
Fh ... First fixing member,
Fp ... Second fixing member,
PH ... Heating device,
Q4 ... Transcription area,
Q5 ... Fixing area,
R4 ... First transport member,
R11 ... Second transport member,
S ... Continuous medium,
T2b ... Transfer member,
U ... Image forming device,
U2c ... Conveyor device.

Claims (7)

A transfer member that transfers an image onto a continuous medium,
A heating device arranged on the downstream side of the transfer member and in contact with one side of the medium to heat the medium.
A fixing device that is arranged on the downstream side of the heating device and fixes an image transferred onto the medium, and is in contact with a first fixing member that contacts the other surface side of the medium and one surface side of the medium. The fixing device having the second fixing member, and
A transport device arranged on the downstream side of the fixing device and transporting the medium while applying tension to the medium.
A first contact member arranged between the heating device and the fixing device and capable of contacting and detaching the medium, a second contact member capable of contacting and detaching the medium, and the first contact member and the first contact member. A route changing means having a rotating body that supports the contact member of 2 and is rotatable about a center of rotation , and
After the image forming operation is completed, the first fixing member and the second fixing member are separated from each other, and the first contact member and the first contact member and the first contact member and the first contact member are subjected to tension while being conveyed by the transfer device. By changing the state of the contact member of 2, the transport path of the medium is set in the direction opposite to the thickness direction of the medium on the upstream side and the downstream side of the path changing means as compared with the transport path before the change. and control means for moving said medium is controlled so as to change the spaced position away from the contact position in contact with the heating device and the fixing device,
An image forming apparatus characterized by being provided with. A heating device that is arranged on the downstream side of the transfer region where the image is transferred to a continuous medium and that contacts and heats one side of the medium.
With respect to the conveying direction of the medium, the arranged downstream of the heating device, and the first fixing member and the second fixing member is a fixing device for fixing an image of the medium in the fixing area facing the The fixing device having a first fixing member in contact with the other surface side of the medium and a second fixing member in contact with the one surface side of the medium .
A first contact member arranged between the heating device and the fixing device and capable of contacting the medium, a second contact member capable of contacting the medium, the first contact member, and a second contact member. A route changing means having a rotating body that supports a contact member and is rotatable about a center of rotation , and
A first transport member arranged on the upstream side of the heating device and transporting the medium with respect to the transport direction of the medium and a first transport member arranged on the downstream side of the fixing device to transport the medium while applying tension to the medium. A transport device having a second transport member, and
When the transport of the medium is stopped, the transport device is used to transport the medium, the first fixing member and the second fixing member are separated from each other, and the rotating body is rotated to rotate the rotating body before the change. Compared to the transport path, the upstream side and the downstream side of the route changing means are moved in a direction opposite to the thickness direction of the medium, and the first contact member is brought into contact with the medium from the heating device. It is a control means for separating the medium and keeping the posture of the medium entering the fixing region by bringing the second contact member into contact with the medium to a posture corresponding to the posture during transporting the medium. When the transfer of the medium is started, the separation between the heating device and the medium is released while rotating the second transfer member, and the holding of the posture of the medium by the second contact member is released. After that, the control means for bringing the first fixing member into contact with the second fixing member, and the control means.
An image forming apparatus characterized by being provided with. The control is provided with the fixing device having a first fixing member in contact with the surface on which the image of the medium is transferred and a second fixing member facing the first fixing member with the medium sandwiched between them. The means is such that when the second contact member is brought into contact with the medium when the transport of the medium is stopped, the medium is separated from both the first fixing member and the second fixing member. The image forming apparatus according to claim 1 or 2, wherein the image forming apparatus is controlled so as to be arranged in. When the control means satisfies the condition for stopping the transport of the preset medium, the control means separates the first fixing member from the second fixing member, and then separates the first contact member and the first fixing member. It is characterized in that the contact member 2 is operated to separate the medium from the heating device and from the first fixing member and the second fixing member, and then control to stop the transport of the medium. The image forming apparatus according to claim 3. When the control means resumes the transfer of the medium, after starting the transfer of the medium, the control means releases the separation between the medium and the heating device means, and the medium, the first fixing member, and the second fixing member. The image forming apparatus according to claim 3 or 4, wherein the first fixing member and the second fixing member are controlled to be brought into contact with each other after the separation from the member is released. A rotating body that supports the first contact member and the second contact member and rotates around a center of rotation.
The image forming apparatus according to any one of claims 1 to 5, wherein the image forming apparatus is provided. Image holder and
A transfer member arranged in the transfer region and transferring an image held by the image holder to a medium,
The control means for separating the transfer member and the image holder when the transport of the medium is stopped, and the control means.
The image forming apparatus according to any one of claims 1 to 6, wherein the image forming apparatus is provided.

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