JP4702250B2 - Droplet discharge device - Google Patents

Description

  The present invention relates to a droplet discharge device that cleans a rotating body to which droplets discharged from a droplet discharge head adhere.

  In an ink jet printer as a droplet discharge device, printing intended to prevent clogging of ink mist and dummy jets that are generated when ink droplets are discharged from a recording head during printing, that is, unused nozzles The ink adheres to a rotating member such as an intermediate transfer member on which an image formed by ink droplets is formed by ejecting ink droplets unrelated to the recording medium, and a cleaning member such as a blade. The rotating body is cleaned by bringing it into contact (see, for example, Patent Documents 1 to 4).

  By the way, as shown in FIG. 27A, it is difficult to clean all the ink adhering to the rotating body 1, and dirt due to the ink I accumulates in the rotating body 1 over time, and finally recording is performed. The medium may be soiled by ink I. As shown in FIG. 27B, this problem is caused by applying a large amount of liquid R such as silicone oil that suppresses the adhesion force of the ink I to the rotating body 1 to the rotating body and using a cleaning member such as a blade. This can be solved by increasing the ink contact pressure.

However, the consumption of liquid such as silicone oil increases, and the wear of cleaning members such as blades increases and the durability of the cleaning members decreases. Therefore, a problem that maintenance costs increase newly arises.
Japanese Patent No. 2873879 JP 11-192768 A Japanese Patent Laid-Open No. 11-48578 JP 2004-130719 A

The present invention has been made in consideration of the above-described facts, and an object thereof is to suppress the accumulation of dirt on the conveying member and to reduce the maintenance cost.

The liquid droplet ejection apparatus according to claim 1 , wherein the liquid droplet ejection head ejects liquid droplets, a conveyance member that conveys a recording medium to face the liquid droplet ejection head, and the conveyance member that contacts the conveyance member and performs the conveyance A cleaning member for cleaning the member , an application member for applying a coating liquid having a property of repelling liquid discharged from the droplet discharge head to the conveyance member , and a conveyance direction of the recording medium conveyed by the conveyance member When the direction length is narrower than the maximum print width of the droplet discharge head , the contact pressure of the cleaning member to the transport member is increased, or the coating liquid is applied to the transport member by the coating member And a cleaning state variable means for increasing the amount.

In the liquid droplet ejection apparatus according to claim 1, conveying member droplets discharged from the droplet discharge head is attached is cleaned by the cleaning member in contact with the conveying member. In addition, the coating liquid is applied to the conveying member by the coating member to form a film of the coating liquid. Since this coating liquid has the property of repelling the liquid discharged from the droplet discharge head, the liquid discharged from the droplet discharge head and adhering to the coating liquid film aggregates on the coating liquid film. To do. Thereby, the cleaning performance of the conveying member by the cleaning member is improved.

Here, the contact pressure between the conveying member of the cleaning member, the coating amount of the coating liquid to the conveying member by the coating member, the coating being applied to the conveying member by the application range, and a coating member of the coating liquid to the conveying member by coating member At least one of the viscosities of the liquid is made variable by the cleaning state changing means.

As a result, it is possible to improve the cleaning performance, reduce the wear of the cleaning member, reduce the coating amount of the coating liquid, and reduce the viscosity of the coating liquid as necessary, so that the conveying member It is possible to suppress the accumulation of dirt on the surface and reduce the maintenance cost. In the droplet discharge device, the recording medium is conveyed by the conveyance member so as to face the droplet ejection head, and the cleaning state varying means has a length in a direction orthogonal to the conveyance direction of the recording medium conveyed by the conveyance member. At least one of the contact pressure of the cleaning member with the conveying member, the amount of coating liquid applied to the conveying member by the coating member, and the application range of the coating liquid to the conveying member by the coating member, depending on (hereinafter referred to as width) To change. Thus, for example, when the amount of liquid adhering to the transport member increases due to the narrow width of the recording medium on the transport member, the contact pressure between the cleaning member and the transport member can be increased, When the application amount of the coating liquid is increased to improve the cleaning ability of the conveying member, while when the width of the recording medium on the conveying member is wide, the amount of liquid adhering to the conveying member decreases. It is possible to reduce the contact pressure of the cleaning member with the conveying member to reduce the wear of the cleaning member, or to reduce the amount of coating liquid applied to the conveying member to reduce the consumption of the coating liquid. Become. Further, since the liquid does not adhere to the range overlapping the recording medium on the conveying member, it is possible to reduce the consumption of the coating liquid without applying the coating liquid to the range by the coating member.

The droplet discharge device according to claim 2 is the droplet discharge device according to claim 1 , further comprising a contamination level detection unit that detects a contamination level of the conveying member , and the cleaning state is variable. The means increases the contact pressure of the cleaning member to the conveying member before the contamination level of the conveying member detected by the contamination level detecting means exceeds an allowable range , or the conveying member by the application member. The coating amount of the coating solution is increased .

In the droplet discharge device according to claim 2 , the level of dirt on the conveying member is detected by the dirt level detecting means, and the cleaning state varying means is adapted to convey the cleaning member according to the detected level of dirt on the conveying member. At least one of the contact pressure with the member and the amount of coating liquid applied to the transport member by the coating member is changed.

As a result, for example, when the conveying member is severely soiled, the cleaning capability is increased by increasing the contact pressure of the cleaning member with the conveying member or increasing the amount of coating liquid applied to the conveying member . It is allowed, whereas, if the contamination of the conveying member is small, to reduce the coating amount of the coating solution to reduce the contact pressure or to reduce the wear of the cleaning member, to the conveying member of the conveying member of the cleaning member coating It is possible to reduce the consumption of liquid. Therefore, it is possible to suppress the accumulation of dirt on the conveying member and to reduce the maintenance cost.

The liquid ejecting device according to claim 3, a droplet discharge device according to claim 1 or claim 2, environment detection means for detecting at least one of temperature and humidity of the surrounding environment of the conveying member And the cleaning state variable means increases the contact pressure of the cleaning member to the transport member when the temperature detected by the environment detection means is higher than a threshold value and the humidity is lower than the threshold value. wherein said increase in said coating solution coating amount of the conveying member, and performing at least one of the reduction in viscosity of the coating solution applied to the conveying member by the applying member by.

In the droplet discharge device according to claim 3 , at least one of the temperature and humidity of the environment around the conveying member is detected by the environment detection unit, and the cleaning state varying unit is set according to at least one of the detected temperature and humidity. However, it changes at least one of the contact pressure between the cleaning member and the conveying member, the amount of coating liquid applied to the conveying member by the coating member, and the viscosity of the coating liquid applied to the conveying member by the coating member.

Thus, the ambient temperature and effects of humidity around the conveying member, when the state of the liquid is in a state as difficult to remove from the conveying member increases the contact pressure between the conveying member of the cleaning member or, by or to increase the coating amount of the coating liquid to the conveying member, to increase the cleaning capability, while the environmental influences of temperature and humidity of the environment of the conveying member, the state of the liquid is removed from the conveying member If the condition is easy, the contact pressure of the cleaning member with the conveying member is decreased to reduce the wear of the cleaning member, or the amount of coating liquid applied to the conveying member is decreased to It is possible to reduce consumption. Accordingly, accumulation of dirt on the conveying member can be suppressed, and maintenance costs can be reduced.

The coating solution applied onto the conveying member by a coating member, can be suppressed to increase the viscosity of the influence of temperature and humidity of the surrounding environment of the conveying member, suppressing deterioration of coatability of the coating liquid to the conveying member it can.

The droplet discharge device according to claim 4 is the droplet discharge device according to any one of claims 1 to 3 , wherein the cleaning state varying unit is configured to apply the cleaning member to the transport member by the application member. The application amount of the application liquid is increased in a range where the contamination in the rotation axis direction of the conveying member is large .

In the droplet discharge device according to the fourth aspect , the cleaning state varying means changes the amount of coating liquid applied to the transport member by the coating member in the direction of the rotation axis of the transport member . Thus, dirt is severe range in the rotation axis direction of the conveying member increases the cleaning capability by increasing the coating amount of the coating liquid, whereas, the coating amount of the coating solution in the range dirt is less in the rotation axis direction of the transport member It is possible to reduce the consumption of the coating liquid by reducing the amount.

The liquid ejecting device according to claim 5, a liquid droplet ejection apparatus according to any one of claims 1 to 3, wherein the cleaning condition varying means, definitive in the rotation axis direction of the conveying member and the The amount of the coating liquid applied to the transport member by the coating member is increased within a range in which the amount of liquid discharged from the droplet discharge head is large .

In the liquid droplet ejection apparatus according to claim 5, the cleaning state varying means, in response to discharge liquid volume difference of the liquid droplet ejection head in a rotary axis direction of the conveying member, the coating liquid to the conveying member by coating member The application amount is changed in the direction of the rotation axis of the conveying member .

Thus, in an amount ranging adhesion is large liquid in the rotation axis direction of the transport member, to increase the coating amount of the coating solution to increase the cleaning capacity, whereas, the scope adhesion amount is small in the liquid in the rotation axis direction of the transport member Then, it becomes possible to reduce the consumption of a coating liquid by reducing the application quantity of a coating liquid.

The liquid ejecting device according to claim 6, a liquid droplet ejection apparatus according to any one of claims 1 to 5, wherein the liquid droplet ejection head, a plurality in the rotational direction of the conveying member The cleaning state varying means is arranged such that the greater the number of droplet ejection heads that eject droplets, the greater the number of droplet ejection heads, the contact pressure of the cleaning member to the conveyance member and the application member to the conveyance member . It is characterized in that at least one of the coating amounts of the coating liquid is increased.

In the droplet discharge device according to the sixth aspect , the plurality of droplet discharge heads are arranged in the rotation direction of the conveying member , and the cleaning state varying means is in accordance with the number of droplet discharge heads that discharge droplets. Then, at least one of the contact pressure of the cleaning member with the conveying member and the amount of coating liquid applied to the conveying member by the applying member is changed.

As a result, when the number of liquid droplet ejection heads for ejecting liquid droplets is large and the amount of liquid adhering to the transport member is large, the contact pressure of the cleaning member to the transport member is increased or the application to the transport member is performed. The cleaning capability is increased by increasing the amount of liquid applied, and on the other hand, if the number of liquid droplet ejection heads that eject liquid droplets is small and the amount of liquid adhering to the conveying member is small, the cleaning member It is possible to reduce the contact pressure on the conveying member to reduce the wear of the cleaning member, or to reduce the amount of coating liquid applied to the conveying member to reduce the consumption of the coating liquid.

The apparatus according to claim 7, a droplet discharge device according to any one of claims 1 to 6, a monochrome printing mode and the full color printing mode is selectable, the The cleaning state variable means increases at least one of a contact pressure of the cleaning member with the transport member and an application amount of the coating liquid onto the transport member by the application member when the full color printing mode is selected. Features.

In the droplet discharge device according to claim 7 , the monochrome printing mode and the full color printing mode can be selected, and the cleaning state varying unit is responsive to whether the monochrome printing mode is selected or the full color printing mode is selected. Then, at least one of the contact pressure of the cleaning member with the conveying member and the amount of coating liquid applied to the conveying member by the applying member is changed.

Thus, for example, when full color printing is performed and the amount of liquid adhering to the transport member increases, the contact pressure of the cleaning member to the transport member is increased, or the amount of coating liquid applied to the transport member is increased. If the amount of liquid adhering to the transport member decreases when the monochrome printing is performed and the amount of liquid adhering to the transport member decreases, cleaning is performed by reducing the contact pressure of the cleaning member to the transport member . It becomes possible to reduce the wear of the member, or to reduce the amount of application liquid consumed by reducing the amount of application liquid applied to the conveying member .

The liquid droplet ejection apparatus according to claim 8 is the liquid droplet ejection apparatus according to any one of claims 1 to 7 , wherein the treatment liquid ejects a treatment liquid containing an aggregating agent that aggregates the liquid. It has a liquid discharge head, the cleaning condition varying means, when the treatment liquid ejection head is ejecting the processing liquid, to the conveying member due to contact pressure and the coating member and the conveying member of the cleaning member At least one of the coating amounts of the coating liquid is increased.

9. The liquid droplet ejection apparatus according to claim 8 , wherein the cleaning state variable means is configured such that the cleaning member contact pressure with the conveying member depends on whether or not the processing liquid ejection head ejects the processing liquid, and the conveying member based on the coating member. At least one of the coating amounts of the coating solution applied to the liquid is changed.

Thereby, for example, when it is difficult to remove the processing liquid and the liquid from the conveying member because the processing liquid and the liquid discharged from the droplet discharge head are mixed on the conveying member , the cleaning member is conveyed. By increasing the contact pressure to the member or increasing the amount of coating liquid applied to the conveying member , the cleaning ability is increased, while the treatment liquid does not adhere to the conveying member , so that the droplet discharge head When it is easy to remove the liquid discharged from the transport member and attached to the transport member , the contact pressure of the cleaning member to the transport member is reduced to reduce the wear of the cleaning member, or the coating liquid applied to the transport member It is possible to reduce the amount of coating liquid consumed by reducing the amount of coating.

The droplet discharge device according to claim 9 is the droplet discharge device according to claim 2 , further comprising a charging unit that charges the transport member, and the dirt level detection unit includes the transport member. It is a surface potential detecting means for detecting the surface potential.

In the droplet discharge device according to the ninth aspect , the conveying member is charged by the charging unit, and the surface potential of the conveying member is detected by the surface potential detecting unit. Here, the contamination of the transfer member accumulates gradually decreases the volume resistivity of the transfer member, the surface potential of the conveying member is gradually increased. That is, having a correlation between the contamination level of the surface potential and the conveying member of the conveying member. Therefore, it is possible to detect the level of contamination of the feeding member by detecting a surface potential of the conveying member.

The droplet discharge device according to claim 10 is the droplet discharge device according to claim 2 , further comprising a charging unit that charges the transport member, and the contamination level detection unit is the charging unit. Current value detecting means for detecting a current value supplied to

In the droplet discharge device according to the tenth aspect , the conveying member is charged by the charging unit, and the current value supplied to the charging unit is detected by the current value detecting unit. Here, as the contamination of the conveying member accumulates, the volume resistivity of the conveying member gradually decreases, and the current value supplied to the charging unit gradually increases. That is, the current value supplied to the charging means and the level of contamination on the conveying member have a relative relationship. For this reason, it is possible to detect the level of contamination of the conveying member by detecting the current value supplied to the charging means.

Since the present invention has the above-described configuration, it is possible to suppress the accumulation of dirt on the conveying member and to reduce the maintenance cost.

  Hereinafter, a first embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 shows an ink jet recording apparatus 12 as a droplet discharge apparatus of the present embodiment. A paper feed tray 16 is provided in the lower part of the casing 14 of the ink jet recording apparatus 12, and the sheets P stacked in the paper feed tray 16 can be taken out one by one by a pickup roll 18. The taken paper P is transported by a plurality of transport roller pairs 20 constituting a predetermined transport path 22.

  Above the paper feed tray 16, an endless transport belt 28 as a rotating body and a transport member is stretched around a drive roll 24 and driven rolls 26, 27, and 29. The driving roll 24 and the driven roll 26 are disposed substantially horizontally, and the driven rolls 27 and 29 are disposed substantially horizontally below the driving roll 24 and the driven roll 26.

  A recording head array 30 is disposed above the conveyor belt 28 and faces a flat portion 28 </ b> F of the conveyor belt 28 between the drive roll 24 and the driven roll 26. This opposed area is an ejection area SE where ink droplets are ejected from the recording head array 30. The sheet P transported along the transport path 22 is held by the transport belt 28 and reaches the discharge area SE, and ink droplets corresponding to image information are attached from the recording head array 30 in a state of facing the recording head array 30. The

  In this embodiment, the recording head array 30 has a long shape in which the effective recording area is equal to or larger than the width of the paper P (the length in the direction orthogonal to the transport direction), and is yellow (Y) and magenta (M). , Cyan (C), and black (K), four ink jet recording heads (hereinafter referred to as recording heads) 32 as liquid droplet ejection heads corresponding to the four colors, respectively, are arranged along the transport direction. Images can be recorded.

  Each recording head 32 is driven by a head drive circuit (not shown). The head drive circuit has a configuration in which, for example, the ejection timing of ink droplets and the ink ejection port (nozzle) to be used are determined according to image information and a drive signal is sent to the recording head 32.

  The recording head array 30 may be stationary in a direction orthogonal to the transport direction. However, if the recording head array 30 is configured to move as necessary, an image with higher resolution can be obtained by multi-pass image recording. Or the failure of the recording head 32 is not reflected in the recording result.

  Four maintenance units 34 corresponding to the respective recording heads 32 are arranged on both sides of the recording head array 30. As shown in FIG. 2, when performing maintenance on the recording head 32, the recording head array 30 is moved upward, and the maintenance unit 34 moves into the gap formed between the conveyance belt 28 and enters. . Then, a predetermined maintenance operation (suction, wiping, capping, etc.) is performed while facing the nozzle surface.

  Further, an ink tank 35 for storing ink of each color is disposed above the recording head array 30. Each recording head 32 is connected to each ink tank 35.

  As shown in FIG. 3, on the upstream side of the recording head array 30, a charging roll 36 as a charging unit connected to a high voltage power supply 38 is disposed. The charging roll 36 is driven while sandwiching the conveyance belt 28 and the paper P with the driven roll 26, and presses the paper P against the conveyance belt 28. At this time, since a predetermined potential difference is generated between the grounded follower roll 26, the sheet P can be electrostatically adsorbed to the transport belt 28 by applying an electric charge to the sheet P.

  A separation claw 40 is disposed on the downstream side of the recording head array 30 and separates the paper P from the conveyance belt 28. The peeled paper P is conveyed by a plurality of discharge roller pairs 42 that constitute a discharge path 44 on the downstream side of the peeling claw 40 and discharged to a paper discharge tray 46 provided at the upper part of the housing 14.

  A belt cleaning unit 48 is disposed below the peeling claw 40. The belt cleaning unit 48 is in contact with a portion of the transport belt 28 wound around the drive roll 24 and scrapes off ink adhering to the transport belt 28 and is transported by the cleaning blade 49 as a cleaning member. A recovery box 51 that recovers ink and the like scraped from the belt 28, and a blade adjustment mechanism 80 that supports the cleaning blade 49 on the recovery box 51 so that the position thereof can be adjusted are provided. Note that an absorber 53 is spread on the bottom of the collection box 51 and absorbs liquid dropped from the cleaning blade 49.

  Further, the oil application unit 64 and the backup plate 66 are opposed to each other between the driven roll 26 and the driven roll 27 with the conveying belt 28 interposed therebetween. The oil application unit 64 faces the outer peripheral surface of the conveyor belt 28, and the backup plate 66 is in contact with the inner peripheral surface of the conveyor belt 28.

  The oil application unit 64 adjusts the position of a case 68, an oil application roll 70 that is rotatably supported by the case 68, an oil application amount adjustment blade 72, and an oil application amount adjustment blade 72. A blade adjusting mechanism 82 supported by the case 68 as possible. The oil application roll 70 is pressed against the driven roll 27 with the conveyance belt 28 interposed therebetween, and rotates following the conveyance belt 28. The oil application roll 70 is formed of a porous material such as polyethylene or urethane, impregnated with silicone oil, and applies the silicone oil to the conveyor belt 28. On the other hand, the ink ejected from the recording head 32 is a water-based ink. For this reason, when ink adheres to the transport belt 28 by unnecessary ink discharge at the time of paper jam or a dummy jet discharged onto the transport belt 28, the water repellent effect of the silicone oil film on the transport belt 28 Ink aggregates. Accordingly, it is possible to suppress an increase in the force with which the ink adheres to the conveyance belt 28, and the ink is easily peeled off from the conveyance belt 28 when the conveyance belt 28 is cleaned by the cleaning blade 49.

  Here, since the dummy jet is performed at a short cycle such as once every several tens of seconds in order to prevent thickening of the ink in the recording head 32, the dummy jet is always on the transport belt 28 as in the present embodiment. It is effective to form a silicone oil film.

  The oil application roll 70 may be a drive roll. In this case, the oil application roll 70 can be prevented from slipping with respect to the conveyor belt 28.

  The oil application amount adjusting blade 72 is in contact with the conveyor belt 28 on the downstream side in the rotation direction of the conveyor belt 28 from the oil application roll 70, and scrapes off the excess silicone oil applied to the conveyor belt 28. The film thickness of the silicone oil is set to a predetermined thickness. The oil application amount adjusting blade 72 is made of a rubber such as fluorine rubber or NBR, a thin metal plate such as SUS, or a resin film such as polyurethane or PET.

  Further, an absorbing member 74 such as a sponge is spread on the bottom of the case 68, and the absorbing member 74 absorbs the silicone oil scraped off from the conveying belt 28 by the oil application amount adjusting blade 72.

  The transport belt 28 is made of a resin such as PET, PI, PA, or PC, or a rubber material such as CR, NBR, HNBR, or urethane rubber, and the surface thereof is coated. The cleaning blade 49 is made of a rubber material such as fluorine rubber, NBR, or HNBR, a thin metal plate such as SUS, or a film formed of a resin such as polyurethane or PET.

  Further, as described above, silicone oil is used as the liquid (hereinafter referred to as application liquid) applied to the conveyor belt 28 by the oil application roll 70, and water-based ink is used as the ink. Here, the coating liquid is suitable for repelling ink. For water-based ink, in addition to silicone oil, higher fatty acids such as oleic acid and linoleic acid, dibutyl phthalate, diisodecyl phthalate, dibutyl maleate Water-repellent liquids such as water-insoluble alcohols such as n-decanol and dimethylbutanol, fluorine oil, mineral oil, and vegetable oil can be used. For oil-based ink, a liquid having high oil repellency such as water can be used.

In addition, in order to stabilize the application of the coating liquid onto the conveyor belt 28, the kinematic viscosity of the coating liquid is desirably in the range of 10 to 10 ⁴ mm ² / s, and in the range of 50 to 10 ² mm ² / s. Is more desirable.

  On the other hand, if the coating thickness of the coating liquid is too thick, the oil may permeate the paper P and the paper P may repel the ink, and the image quality may be adversely affected. Since the cleaning of the ink by the cleaning blade 49 cannot be performed satisfactorily, it is necessary to set the coating thickness of the coating liquid within an appropriate range. A suitable range of the coating thickness of the coating solution is 1 nm to 20 μm.

  Further, the coating solution needs to be non-volatile at room temperature. Specifically, the vapor pressure is 13.33 Pa or less at 25 ° C. Further, the coating liquid needs to be incompatible with ink. Specifically, the solubility in ink is 0.1 wt% or less at normal temperature (25 ° C.).

Further, since the coating liquid needs to spread wet on the conveyor belt 28, the relationship of the following formula (A) is necessary. However, as shown in FIG. 4, the surface tension of the coating liquid T is γ ₀ and the critical surface tension γ _b of the conveyor belt 28 is set. The critical surface tension is the relationship between the surface tension of various liquids and the contact angle θ of the solid surface, when cos θ is corrected to 1 (that is, when the contact angle of the liquid with respect to the solid surface becomes 0 °). Refers to the surface tension. In general, a solid surface wets well with a liquid having a surface tension smaller than the critical surface tension of the surface.

γ ₀ <γ _b (A)

Further, in order to give the coating liquid T water repellency, the relationship of the following formula (B) is required. However, the surface tension of the ink I is γ _i .

γ ₀ <γ _i (B)

As a result, the ink I aggregates without spreading on the film of the coating liquid T. The transport belt 28 is a PET belt with a critical surface tension γ _b of about 43 [mN / m], the coating liquid is silicone oil with a surface tension γ ₀ of about 20 [mN / m], and the ink has a surface tension γ _i. As a result of conducting an experiment for evaluating the cleaning performance as a water-based ink of about 30 [mN / m], there was no ink residue on the conveying belt 28, and the cleaning property was good.

  Here, at least one of the contact state of the cleaning blade 49 with the conveyance belt 28 and the application state of the silicone oil to the conveyance belt 28 by the oil application unit 64 is made variable. (See FIG. 3) will be described.

  As shown in FIG. 3, the contact state varying unit 15 includes a blade adjustment mechanism 80 that adjusts the position of the cleaning blade 49, a blade adjustment mechanism 82 that adjusts the position of the coating amount adjustment blade 72, and the entire inkjet recording apparatus 12. And a control unit 11 that performs control.

  As shown in FIGS. 5A and 5B, the blade adjusting mechanism 80 is provided at both longitudinal ends of the cleaning blade 49, and includes a moving body 84, a support member 86, a cam 88, and a pair of tension members. A coil spring 90.

  The moving body 84 is a member having a trapezoidal cross section in the longitudinal direction of the cleaning blade 49, intersecting the surfaces 84A and 84B parallel to each other, the surface 84C orthogonal to the surfaces 84A and 84B, and the surface 84A at an acute angle, A surface 84B and a surface 84D intersecting at an obtuse angle are provided, and an acute angle portion 84E is formed by the surface 84A and the surface 84D.

  The support member 86 is a member having a U-shaped cross section in the longitudinal direction of the cleaning blade 49, and includes side walls 86A and 86B that are parallel to each other and a bottom wall 86C that is orthogonal to the side walls 86A and 86B. Further, the support member 86 is opened to the conveyor belt 28 side, and is supported by the case 51 so that the side wall 86A is located downstream of the side wall 86B in the belt rotation direction.

  Here, the moving body 84 is disposed between the side wall 86A and the side wall 86B so that the surface 84A contacts the side wall 86A, the surface 84B abuts the side wall 86B, and the surface 84C faces the bottom wall 86C. It can move to the conveyor belt 28 side or the counter conveyor belt 28 side. Further, one end in the width direction of the cleaning blade 49 is fixed to the acute angle portion 84E side of the surface 84D, and the other end in the width direction of the cleaning blade 49 protrudes from the acute angle portion 84E to the conveying belt 28 side.

  The cam 88 is a disc-shaped eccentric cam in which the rotation shaft 88A is eccentric. The rotation axis 88A of the cam 88 extends along the longitudinal direction of the cleaning blade 49 between the surface 84C and the bottom wall 86C, and the cam 88 is rotatable between the surface 84C and the bottom wall 86C. It has become. The pair of tension coil springs 90 are attached to both sides of the cam 88 with one end on the surface 84C and the other end on the bottom wall 86C, and bias the moving body 84 toward the bottom wall 86C. It is press-contacted to the circumferential surface.

  For this reason, when the cam 88 rotates, the moving body 84 moves to the conveying belt 28 side against the urging force of the tension coil spring 90, and moves to the anti-conveying belt 28 side in response to the urging force of the tension coil spring 90. To do.

  Here, the other end in the width direction of the cleaning blade 49 protrudes from the acute angle portion 84 </ b> E toward the conveyance belt 28, and can contact the conveyance belt 28. For this reason, as shown in FIG. 5A, the cleaning blade 49 is moved to the conveying belt 28 side by the movement of the moving body 84 toward the conveying belt 28 by the rotation of the cam 88, and the conveying belt 28 of the cleaning blade 49 is moved. The amount of biting into the belt is increased, and the contact pressure of the cleaning blade 49 on the conveyor belt 28 is increased. This increases the amount of force that the cleaning blade 49 scrapes off the ink. Further, as shown in FIG. 5B, the cleaning blade 49 is moved to the anti-conveyance belt 28 side by the movement of the moving body 84 to the anti-conveyance belt 28 side by the rotation of the cam 88, and the conveyance belt of the cleaning blade 49 is moved. The amount of biting into the belt 28 is reduced, and the contact pressure between the cleaning blade 49 and the conveyor belt 28 is reduced. As a result, the frictional force between the cleaning blade 49 and the conveyor belt 28 is reduced, and wear of the cleaning blade 49 is reduced.

  In addition, a stepping motor 89 is provided that applies a rotational force to the rotating shaft 88A of the cam 88 via a gear (not shown). The stepping motor 89 is controlled by the control unit 11 (see FIG. 3) that controls the entire inkjet recording apparatus 12, and the cleaning blade 49 is applied to the conveying belt 28 according to the driving amount and driving direction of the stepping motor 89. The amount of bite is increased or decreased.

  The angle between the cleaning blade 49 and the conveyor belt 28 is set to 50 ° to 70 °.

  Next, the blade adjustment mechanism 82 that adjusts the position of the coating amount adjustment blade 72 will be described.

  As shown in FIGS. 6A and 6B, the blade adjustment mechanism 82 includes a moving body 108, a support member 86, a cam 110, and a pair of tension coil springs 90. The moving body 108 has a shape in which the angle of the surface 84 </ b> D of the moving body 84 included in the blade adjustment mechanism 80 is changed, and is supported by the support member 86 in the same manner as the moving body 84. The cam 110 is a disc-shaped eccentric cam in which the diameter of the cam 88 provided in the blade adjustment mechanism 80 and the position of the rotation shaft are changed. Like the cam 88, the cam 110 is disposed between the pair of tension coil springs 90. The movable body 108 is pressed against the circumferential surface of the cam 110 by the urging force of the tension coil spring 90.

  For this reason, when the cam 110 rotates, the moving body 108 moves to the conveying belt 28 side against the urging force of the tension coil spring 90, and moves to the counter-conveying belt 28 side by the urging force of the tension coil spring 90.

  As shown in FIG. 6A, the application amount adjusting blade 72 is moved to the conveying belt 28 side by the movement of the moving body 108 toward the conveying belt 28 due to the rotation of the cam 110, and the conveying belt of the applying amount adjusting blade 72 is moved. The amount of biting into 28 is increased. Further, as shown in FIG. 6B, the application amount adjusting blade 72 is moved to the anti-conveyance belt 28 side by the movement of the moving body 108 to the anti-conveyance belt 28 side by the rotation of the cam 110, and the application amount adjusting blade The amount of biting 72 into the conveyor belt 28 is reduced.

  Here, depending on various conditions of the coating amount adjusting blade 72, when the angle between the coating amount adjusting blade 72 and the transport belt 28 is set to a shallow angle of about 10 ° to 30 °, the transport belt of the coating amount adjusting blade 72 is set. It has been experimentally confirmed that the coating amount adjusting blade 72 can manage the amount of scraping of the silicone oil from the transport belt 28 by changing the amount of biting into the belt 28.

  When the angle between the coating amount adjusting blade 72 and the conveying belt 28 is set to an angle deeper than 30 °, the amount of silicone oil scraped off from the conveying belt 28 by the coating amount adjusting blade 72 becomes excessive, and the blade Even if the amount of biting into the conveyor belt 28 is changed, there is almost no difference in the amount of silicone oil that the application amount adjusting blade 72 scrapes off from the conveyor belt 28. On the other hand, when the angle between the coating amount adjusting blade 72 and the transport belt 28 is set to an angle shallower than 10 °, the silicone oil is hardly scraped off from the transport belt 28 by the coating amount adjusting blade 72. For this reason, in this embodiment, the angle between the coating amount adjusting blade 72 and the conveyor belt 28 is set to about 10 ° to 30 °.

  Here, when the angle between the coating amount adjusting blade 72 and the conveying belt 28 is set to about 10 ° to 30 °, the coating amount adjusting blade 72 is applied as the amount of biting into the conveying belt 28 increases. As the scraping amount of the silicone oil from the conveyor belt 28 by the amount adjusting blade 72 decreases and the biting amount of the coating amount adjusting blade 72 into the conveyor belt 28 decreases, the silicone from the conveyor belt 28 by the coating amount adjusting blade 72 decreases. Experiments have confirmed that the amount of oil scraping increases.

  This is because as the biting amount of the coating amount adjusting blade 72 into the transport belt 28 increases, the deflection of the coating amount adjusting blade 72 increases, and the angle between the edge of the coating amount adjusting blade 72 and the transport belt 28 decreases. As a result, the amount of force with which the coating amount adjusting blade 72 scrapes the silicone oil from the conveying belt 28 is reduced, and the amount of biting of the coating amount adjusting blade 72 into the conveying belt 28 is reduced, so that the coating amount adjusting blade 72 is bent. This is presumably because the amount of the application amount adjusting blade 72 scraping the silicone oil from the conveying belt 28 increases as the angle between the edge of the applying amount adjusting blade 72 and the conveying belt 28 increases.

  In addition, a stepping motor 111 is provided that applies a rotational force to the rotating shaft 110A of the cam 110 via a gear (not shown). The stepping motor 111 is controlled by the control unit 11 (see FIG. 3), and the amount of biting of the coating amount adjusting blade 72 into the transport belt 28 is increased or decreased according to the driving amount and driving direction of the stepping motor 111.

  Here, as shown in FIG. 3, the surface potential sensor 13 serving as the dirt level detecting means and the surface potential detecting means is disposed on the upstream side in the belt rotation direction of the recording head 32 and on the downstream side in the belt rotation direction of the charging roll 36. The surface potential of the outer peripheral surface of the conveyor belt 28 is detected by the surface potential sensor 13, and a detection signal is transmitted to the control unit 11. The control unit 11 stores a threshold value V0 of the surface potential of the outer peripheral surface of the conveyor belt 28, and when a print command or a cleaning mode execution command is received from an external device or the like, the detected value by the surface potential sensor 13 is equal to or greater than the threshold value V0. Whether or not, and the stepping motors 89 and 111 are controlled according to the determination result. As a result, the amount of biting of the cleaning blade 49 into the conveying belt 28 and the amount of silicone oil applied to the conveying belt 28 are adjusted.

  Here, as dirt due to ink accumulates over time on the outer peripheral surface of the conveyor belt 28, the volume resistivity of the conveyor belt 28 gradually decreases, and the surface potential V of the outer peripheral surface of the conveyor belt 28 is a predetermined value in the initial state. The voltage gradually increases from Vlow (for example, 1000 V as shown in the graph of FIG. 7). That is, the surface potential V on the outer peripheral surface of the conveyor belt 28 and the level of smear due to ink on the outer peripheral surface of the conveyor belt 28 are correlated. Therefore, in the present embodiment, the level of contamination due to ink on the outer peripheral surface of the conveyor belt 28 is detected by detecting the surface potential V of the outer peripheral surface of the conveyor belt 28.

  The threshold value V0 is between the surface potential Vlow of the outer peripheral surface of the conveyor belt 28 in the initial state and the surface potential Vhigh of the outer peripheral surface of the conveyor belt 28 in an abnormal state where the level of stain due to ink is outside the allowable range (for example, It is set to 1300V) as shown in the graph of FIG.

  Hereinafter, a method for adjusting the amount of silicone oil applied to the cleaning blade 49 and the conveyor belt 28 will be described with reference to the flowchart of FIG.

  First, an adjustment method when the control unit 11 receives a print command will be described.

  First, when the control unit 11 receives a print command, a processing routine is started and the process proceeds to step 1. In step 1, a drive signal is transmitted from the control unit 11 to a motor (not shown) that drives the drive roll 24, and the conveyor belt 28 is driven. Next, in step 2, sensing of the surface potential of the outer peripheral surface of the conveyor belt 28 by the surface potential sensor 13 is started, and the process proceeds to step 3.

  In step 3, whether or not the conveyor belt 28 has made one round after the surface potential sensor 13 starts sensing the surface potential of the outer circumference of the conveyor belt 28, that is, data on the surface potential for one revolution of the conveyor belt 28. If the determination is affirmative, the process proceeds to step 4.

  In step 4, the transmission of the drive signal from the control unit 11 to the motor that drives the drive roll 24 is stopped, and the drive of the conveyor belt 28 is stopped. Next, in step 5, it is determined whether or not the maximum value Vmax of the surface potential for one rotation of the conveyor belt 28 detected by the surface potential sensor 13 is equal to or greater than the threshold value V0. If the determination is negative, the process proceeds to 7.

  In step 6, a drive signal is transmitted from the control unit 11 to at least one of the stepping motors 89 and 111, the amount of biting into the conveying belt 28 of the cleaning blade 49 is increased from the initial state, and the conveying belt 28 of the application amount adjusting blade 72. At least one operation of reducing the amount of biting into the initial state is performed. Next, in step 7, a drive signal is transmitted from the control unit 11 to each unit, a printing operation is started, and the processing routine is ended.

  Next, an adjustment method when the control unit 11 receives a cleaning mode execution command will be described with reference to a flowchart of FIG.

  First, when the control unit 11 receives a cleaning mode execution command, the processing routine is started and the routine proceeds to step 11. In step 11, a drive signal is transmitted from the control unit 11 to a motor (not shown) that drives the drive roll 24, and the transport belt 28 is driven. Next, in step 12, sensing of the surface potential of the outer peripheral surface of the conveyor belt 28 by the surface potential sensor 13 is started, and the process proceeds to step 3.

  In step 13, whether or not the conveyor belt 28 has made one revolution since the surface potential sensor 13 has started sensing the surface potential of the outer circumference of the conveyor belt 28, that is, data on the surface potential for one revolution of the conveyor belt 28. If the determination is affirmative, the process proceeds to step 14.

  In step 14, transmission of the drive signal from the control unit 11 to the motor that drives the drive roll 24 is stopped, and the drive of the transport belt 28 is stopped. Next, in step 15, it is determined whether or not the maximum value Vmax of the surface potential for one rotation of the conveyor belt 28 detected by the surface potential sensor 13 is equal to or greater than the threshold value V0. If the determination is negative, the process proceeds to 19.

  In step 19, a driving signal is transmitted from the control unit 11 to each unit to perform a cleaning operation (for example, with the cleaning blade 49, the oil application roll 70, and the application amount adjustment blade 72 in contact with the conveyance belt 28). Are rotated for one minute).

  On the other hand, in step 16, a drive signal is transmitted from the control unit 11 to at least one of the stepping motors 89 and 111, the amount of biting into the conveying belt 28 of the cleaning blade 49 is increased from the initial set amount, and the application amount adjusting blade 72 At least one operation of reducing the amount of biting into the conveyor belt 28 from the initial set amount is executed. Next, in step 17, a driving signal is transmitted from the control unit 11 to each unit to start a cleaning operation, and the process proceeds to step 18.

  In step 18, a drive signal is transmitted from the control unit 11 to at least one of the stepping motors 89 and 111, the amount of biting into the conveying belt 28 of the cleaning blade 49 is reduced to the initial set amount, and the conveying belt of the coating amount adjusting blade 72 At least one of the operations of increasing the amount of biting into 28 to the initial set amount is executed.

Then, the processing routine ends.

  That is, in this embodiment, the contact pressure of the cleaning blade 49 to the conveyor belt 28 is increased from the initial set amount before the level of contamination by the ink on the outer peripheral surface of the conveyor belt 28 is likely to exceed the allowable range. The amount of silicone oil applied to the belt 28 is increased from the initial set amount, and the initial set amounts of the contact pressure of the cleaning blade 49 to the conveyor belt 28 and the amount of silicone oil applied to the conveyor belt 28 are low. Set it in your eyes.

  Accordingly, it is possible to improve the durability by reducing the wear of the cleaning blade 49, reduce the consumption of the silicone oil, and suppress the accumulation of dirt on the conveyor belt 28.

  In the present embodiment, the surface potential of the outer peripheral surface of the conveyor belt 28 is detected by detecting the surface potential of the outer peripheral surface of the conveyor belt 28 by the surface potential sensor 13, but as shown in FIG. An ammeter 39 may be provided in the circuit 37 that supplies current to the charging roller 36, and the current supplied to the charging roll 36 may be detected by the ammeter 39 to detect the level of contamination on the outer peripheral surface of the conveyor belt 28.

  This is because, as dirt on the outer peripheral surface of the conveyor belt 28 accumulates, the volume resistivity of the conveyor belt 28 gradually decreases, and the current value supplied to the charging roll 36 gradually increases. This is because there is a relative relationship between the value of the current supplied to and the level of dirt on the outer peripheral surface of the conveyor belt 28.

  Next, a blade adjustment mechanism 92, which is a modification of the blade adjustment mechanism 80, will be described with reference to FIGS. In addition, the same code | symbol is attached | subjected to the structure similar to the blade adjustment mechanism 80, and description is abbreviate | omitted.

  As shown in FIGS. 11A and 11B, the blade adjustment mechanism 92 includes a moving body 84, a support member 86, a cam 88, a pair of tension coil springs 90, and a rotation adjustment mechanism 94. Yes. The moving body 84, the support member 86, the cam 88, and the pair of tension coil springs 90 are combined in the same manner as the blade adjustment mechanism 80.

  The rotation adjusting mechanism 94 includes an arm member 96, a support member 98, a cam 102, and a compression coil spring 106. The arm member 96 is a plate material having one end portion in the longitudinal direction bent to one side in the width direction, and one end in the longitudinal direction is formed outside the bottom wall 86C of the support member 86 so that the thickness direction is parallel to the longitudinal direction of the cleaning blade 49. Installed part. A rotation shaft 96 </ b> A extending in the thickness direction is provided on one end side in the longitudinal direction of the arm member 96.

  The support member 98 is a frame disposed on the side opposite to the conveying belt 28 of the support member 86, and includes a support wall 98 </ b> A orthogonal to the longitudinal direction of the cleaning blade 49. A rotation shaft 96A is attached to the support wall 98A so as to be perpendicular and rotatable, and the arm member 96 can rotate about the rotation shaft 96A. The support member 98 is formed with an attachment wall 98B orthogonal to the support wall 98A on the upstream side of the rotation shaft 96A in the belt rotation direction.

  Similarly to the cam 88, the cam 102 is a disc-shaped eccentric cam in which the rotation shaft 102A is eccentric. The rotation shaft 102A of the cam 102 extends in the longitudinal direction of the cleaning blade 49 on the downstream side of the belt rotation direction of the arm member 96, and is rotatably attached to the support wall 98A.

  The compression coil spring 106 has one end attached to the attachment wall 98B and the other end attached to the other end in the longitudinal direction of the arm member 96. The one end in the longitudinal direction of the arm member 96 faces the anti-attachment wall 98B. It is urged and pressed against the circumferential surface of the cam 102.

  Therefore, when the cam 102 rotates, the arm member 96 rotates counterclockwise in the figure against the biasing force of the compression coil spring 106, and rotates in the clockwise direction in the figure by the biasing force of the compression coil spring 106. To do. As a result, as shown in FIG. 11A, the rotation of the arm member 96 due to the rotation of the cam 102 causes the cleaning blade 49 to move downstream in the belt rotation direction due to the rotation in the counterclockwise direction in the figure. The angle with the conveying belt 28 is reduced. As a result, the frictional force between the cleaning blade 49 and the conveyor belt 28 is reduced. Also, as shown in FIG. 11B, the cleaning blade 49 is moved upstream in the belt rotation direction by the rotation of the arm member 96 in the clockwise direction in FIG. The angle with 28 is increased. This increases the amount of force that the cleaning blade 49 scrapes off the ink.

  In addition, a stepping motor 103 is provided that applies a rotational force to the rotating shaft 102A of the cam 102 via a gear (not shown). The stepping motor 103 is controlled by the control unit 11 described above, and the angle between the cleaning blade 49 and the conveying belt 28 is increased or decreased according to the driving amount and driving direction of the stepping motor 103. As a result, the amount of force that the cleaning blade 49 scrapes the ink increases or decreases.

  If the angle of the cleaning blade 49 is adjusted by the rotation adjusting mechanism 94 after the amount of biting of the cleaning blade 49 into the conveyance belt 28 is adjusted, the angle is adjusted and then the cleaning blade 49 is moved to the conveyance belt 28. Therefore, after adjusting the angle of the cleaning blade 49, it is desirable to adjust the amount of biting of the cleaning blade 49 into the conveyor belt 28.

  Next, an oil application unit 200 according to a first modification of the oil application unit 64 will be described with reference to FIG. In addition, the same code | symbol is attached | subjected to the structure similar to the oil application | coating knit 64, and description is abbreviate | omitted.

  As shown in FIG. 12, the oil application unit 200 includes an oil application roll 202, an oil supply unit 204, and a roll adjustment mechanism 206. The oil application roll 202 has a configuration in which a roll portion 202B is formed of a porous body on the peripheral surface of the rotation shaft 202A.

  The oil supply unit 204 includes a case 206 that contains silicone oil, and a felt 208 that is immersed in the silicone oil in the case 206 and is in contact with the oil application roll 202. The oil application roll 202 is always replenished via the felt 208.

  The roll adjusting mechanism 206 is provided at both axial ends of the oil application roll 202, and includes a bearing 210, a support member 212, a cam 214, a compression coil spring 216, and a movable plate 218.

  The bearing 210 is a member having a rectangular cross section in the axial direction of the oil application roll 202, and is rotatably attached to the axial end of the rotating shaft 202A. The support member 212 is a member having a U-shaped cross section in the axial direction of the oil application roll 202, and includes side walls 212A and 212B that are parallel to each other and a bottom wall 212C that is orthogonal to the side walls 212A and 212B. . The support member 212 is disposed so as to open toward the transport belt 28, and supports the bearing 210 so as to be movable toward the transport belt 28 or the anti-transport belt 28.

  The cam 214 is a disc-shaped eccentric cam in which the rotation shaft 214A is eccentric. The rotating shaft 214A of the cam 214 extends along the longitudinal direction of the oil application roll 202 between the bearing 210 and the bottom wall 212C, and the cam 214 is rotatable between the bearing 210 and the bottom wall 212C. It has become. Further, the movable plate 218 is supported by the support member 212 so as to be movable between the bearing 210 and the bottom wall 212C toward the conveying belt 28 or the opposite conveying belt 28.

  The compression coil spring 216 has one end attached to the bearing 210 and the other end attached to the movable plate 218. The compression coil spring 216 urges the bearing 210 toward the conveying belt 28 to press-contact the outer peripheral surface of the conveying belt 28. Is urged toward the cam 214 to be brought into pressure contact with the movable plate 218.

  For this reason, when the cam 214 rotates, the movable plate 218 moves toward the conveying belt 28 against the urging force of the compression coil spring 216, so that the bearing 210 moves toward the conveying belt 28, and the movable plate 218 moves The bearing 210 moves to the anti-conveyance belt 28 side by moving to the anti-conveyance belt 28 side by the urging force of the compression coil spring 216.

  For this reason, the oil application roll 202 is moved to the conveyance belt 28 side by the movement of the bearing 210 to the conveyance belt 28 side by the rotation of the cam 214, and the amount of biting of the roll portion 202B into the conveyance belt 28 is increased. As a result, the amount of silicone oil applied to the conveyor belt 28 increases. Further, the oil application roll 202 is moved to the anti-conveyance belt 28 side by the movement of the bearing 210 to the anti-conveyance belt 28 side by the rotation of the cam 214, and the amount of biting of the roll portion 202B into the conveyance belt 28 is reduced. As a result, the amount of silicone oil applied to the conveyor belt 28 is reduced.

  In addition, a stepping motor 228 is provided that applies a rotational force to a rotation shaft 214A of the cam 214 of the oil application unit 200 via a gear (not shown). The stepping motor 228 is controlled by the control unit 111, and the amount of biting of the oil application roll 202 into the conveying belt 28 is increased or decreased according to the driving amount and driving direction of the stepping motor 228.

  Further, the heater 224 that extends along the axial direction of the oil application roll 202 and faces the peripheral surface of the oil application roll 202, and the periphery of the conveyor belt 28 (for example, in the vicinity of the oil application unit 200 as shown). A temperature / humidity sensor 226 that detects the temperature and humidity of the environment is provided, and a detection signal is transmitted from the temperature / humidity sensor 226 to the control unit 111.

  The control unit 111 stores the temperature threshold values Tlow and High (> Tlow) of the environment around the transport belt 28 and the humidity threshold value Wlow of the environment around the transport belt 28 and receives a print command from an external device. Then, it is determined whether the temperature detection value T by the temperature / humidity sensor 226 is less than the threshold value Tlow, the threshold value Tlow or more and less than the threshold value High, or the threshold value High or more, and the humidity by the temperature / humidity sensor 226 is determined. It is determined whether or not the detected value W is equal to or greater than the threshold value Wlow, and the stepping motors 89 and 228 and the heater 224 are controlled according to the determination result.

  Next, a method for adjusting the cleaning blade 49, the oil application roll 202, and the heater 224 when the control unit 111 receives a print command will be described with reference to the flowchart of FIG.

  First, when the control unit 111 receives a print command, a processing routine is started and the process proceeds to step 101. In step 101, sensing of the temperature T and humidity W around the conveyor belt 28 by the temperature / humidity sensor 226 is started, and the process proceeds to step 102.

  In step 102, it is determined whether or not the temperature T detected by the temperature / humidity sensor 226 is less than the threshold value Tlow, the threshold value Tlow or more and less than the threshold value High, or the threshold value High or more. The process proceeds to step 104. If the threshold value is Tlow or more and less than the threshold value High, the process proceeds to step 103.

  In step 103, it is determined whether or not the humidity W detected by the temperature / humidity sensor 226 is equal to or higher than the threshold value Wlow. If the determination is affirmative, the process proceeds to step 106, and if the determination is negative, the process proceeds to step 105. .

  In step 104, a drive signal is transmitted from the controller 111 to the heater 224, the heater 224 is turned on, and the temperature of the environment around the conveyor belt 28 rises. Here, the silicone oil becomes highly viscous in a low temperature environment and is difficult to be applied to the conveyor belt 28. However, in this step, since the heater 224 raises the temperature of the environment around the conveyance belt 28, the increase in the viscosity of the silicone oil is suppressed, and the decrease in the applicability of the silicone oil to the conveyance belt 28 is suppressed.

  In step 105, a drive signal is transmitted from the control unit 111 to at least one of the stepping motor 89 and the stepping motor 228, the amount of biting of the cleaning blade 49 into the conveying belt 28 from the initial state, and the oil application roll 202 At least one operation of increasing the amount of biting into the conveyor belt 28 from the initial state is executed. Next, in step 106, a drive signal is transmitted from the control unit 111 to each unit, a printing operation is started, and the processing routine is ended.

  That is, the ink easily dries in a high temperature environment and a low humidity environment, and increases the adhesion force to the conveyance belt 28. Therefore, in a high temperature environment and a low humidity environment, the amount of biting of the oil application roll 202 into the conveyance belt 28 is reduced. By increasing the amount of silicone oil applied to the conveyor belt 28 from the initial state, an increase in the adhesion of ink to the conveyor belt 28 is suppressed, and the amount of biting of the cleaning blade 49 into the conveyor belt 28 is suppressed. Is increased from the initial state, and the amount of the cleaning blade 49 scraping off the ink from the conveying belt 28 is increased.

  On the other hand, the ink becomes difficult to dry in a low temperature, constant temperature environment, constant humidity, and high humidity environment, and the adhesion force to the conveyance belt 28 is reduced. Each initial set amount of the silicone oil applied to the belt 28 is set to a low value.

  As a result, accumulation of dirt on the conveyor belt 28 can be suppressed, durability of the cleaning blade 49 can be reduced, and the consumption of silicone oil can be reduced, thereby reducing maintenance costs.

  Next, an oil application unit 240 of a second modification of the oil application unit 64 will be described with reference to FIG.

  As shown in FIG. 14, the oil application unit 240 includes an oil application roll 242, an oil supply roll 244, an application amount adjustment blade 246, a blade adjustment mechanism 248, and a case 250.

  The case 250 contains silicone oil. The oil supply roll 244 is a roll formed of a porous body and is immersed in the silicone oil in the case 250. The oil application roll 240 is in contact with the oil supply roll 244 and the conveyor belt 28, and the silicone oil in the case 250 is constantly supplied to the oil application roll 242 through the oil supply roll 240.

  The application amount adjusting blade 246 is supported by the blade adjusting mechanism 248 and is in contact with the oil application roll 242. The silicone oil adhering to the oil application roll 242 is scraped off and applied to the conveyor belt 28 from the oil application roll 242. Adjust the amount of silicone oil that is played.

  The blade adjustment mechanism 248 has the same configuration as the blade adjustment mechanism 80 described above, and moves the application amount adjustment blade 246 to the oil application roll 242 side so that the application amount adjustment blade 246 is applied to the oil application roll 242. Increase the amount of bite. As a result, the amount by which the application amount adjusting blade 246 scrapes the silicone oil from the oil application roll 242 decreases, and the amount of silicone oil applied to the conveyor belt 28 increases.

  Further, the blade adjustment mechanism 246 moves the application amount adjustment blade 246 toward the anti-oil application roll 242 side to reduce the amount of biting of the application amount adjustment blade 246 into the oil application roll 242. As a result, the amount by which the application amount adjusting blade 246 scrapes the silicone oil from the oil application roll 242 increases, and the amount of silicone oil applied to the conveyor belt 28 decreases.

  Next, a second embodiment of the present invention will be described. In addition, the same code | symbol is attached | subjected about the structure similar to 1st Embodiment, and description is abbreviate | omitted.

  As shown in FIG. 15, in the ink jet recording apparatus 300 of the present embodiment, the treatment liquid discharge head 230 is disposed on the outer peripheral surface of the transport belt 28 on the upstream side of the recording head 32 in the belt rotation direction and on the downstream side of the charging roll 36 in the belt rotation direction. It is arrange | positioned facing. The processing liquid discharge head 230 discharges a processing liquid such as a flocculant to the conveying belt 28 side.

  The recording head 32 and the treatment liquid discharge head 230 are controlled by a control unit 302 that controls the entire inkjet recording apparatus 300, and are driven when the control unit 302 receives a print command.

  Hereinafter, a method of adjusting the amount of silicone oil applied to the conveyor belt 28 when the control unit 302 receives a print command will be described with reference to the flowchart of FIG.

  First, when the control unit 302 receives a print command, a processing routine is started and the process proceeds to step 201. In step 201, it is determined whether or not the width D of the paper P (see FIGS. 17A and 17B) is equal to or larger than the maximum print width of the processing liquid ejection head 230. If the determination is affirmed, the process proceeds to step 203. If the determination is negative, the process proceeds to step 202.

  In step 202, a drive signal is transmitted from the controller 302 to the stepping motor 111, and the amount of biting of the coating amount adjustment blade 72 into the transport belt 28 is increased. As a result, the amount of silicone oil scraped by the coating amount adjusting blade 72 decreases, and the amount of silicone oil applied to the conveyor belt 28 increases. Then, the process proceeds to step 203.

  In step 203, a drive signal is transmitted from the control unit 302 to each unit, a printing operation is started, and the processing routine ends.

  By the way, the recording head 32 and the processing liquid discharge head 230 discharge ink and processing liquid every few seconds to several tens of seconds irrespective of image formation in order to prevent clogging of unused nozzles (so-called dummy jets). However, at this time, the ink is ejected between the paper P on the transport belt 28 and the processing liquid is ejected onto the paper P. This is because the ink is colored and visually recognized when ejected onto the paper P, whereas the treatment liquid is colorless and transparent and is not visually recognized even when ejected onto the paper P.

  Here, as shown in FIG. 17A, when the width of the paper P (the length in the direction orthogonal to the transport direction) is wider than the maximum printing width of the processing liquid discharge head 230, the discharge from the processing liquid discharge head 230 is performed. All of the processed liquid S adheres to the paper P, but as shown in FIG. 17B, when the width of the paper P is narrower than the maximum printing width of the processing liquid discharge head 230, The treatment liquid S also adheres to the outside in the width direction of the paper P. For this reason, the ink and the processing liquid S are mixed on the outer side in the width direction of the paper P on the transport belt 28, and the ink is aggregated and is hardly scraped off from the transport belt 28.

  Therefore, in this embodiment, when the width of the paper P is narrower than the maximum printing width of the processing liquid discharge head 230, the amount of silicone oil applied to the transport belt 28 is increased from the initial set amount, and the silicone to the transport belt 28 is increased. The initial set amount of oil application is set to a low value.

  As a result, it is possible to suppress the accumulation of dirt on the conveyor belt 28 regardless of the width of the paper P and to reduce the maintenance cost by reducing the consumption of silicone oil.

  In the present embodiment, only the amount of silicone oil applied to the conveyor belt 28 is changed. However, the contact state of the cleaning blade 49 with the conveyor belt 28 may also be changed.

  Next, a modification of the method for adjusting the amount of silicone oil applied to the conveyor belt 28 when the control unit 302 receives a print command will be described with reference to the flowchart of FIG.

  First, when the control unit 302 receives a print command, a processing routine is started and the process proceeds to step 301. In step 301, it is determined whether or not it is a high image quality mode using a processing liquid. If the determination is affirmed, the process proceeds to step 302. If the determination is affirmed, the process proceeds to step 303.

  In step 302, a drive signal is transmitted from the controller 302 to the stepping motor 111, and the amount of biting of the coating amount adjustment blade 72 into the transport belt 28 is increased. As a result, the amount of silicone oil scraped by the coating amount adjusting blade 72 decreases, and the amount of silicone oil applied to the conveyor belt 28 increases. Then, the process proceeds to step 303.

  In step 303, a drive signal is transmitted from the control unit 302 to each unit to start a printing operation, and the processing routine ends.

  That is, when the processing liquid is discharged from the processing liquid discharge head 230 and mixing of the ink and the processing liquid occurs on the transport belt 28, the amount of silicone oil applied to the transport belt 28 is increased from the initial set amount, The initial set amount of silicone oil applied to the conveyor belt 28 is set to a low value.

  As a result, accumulation of dirt on the conveyor belt 28 can be suppressed, and maintenance costs can be suppressed by reducing the consumption of silicone oil.

  Next, a third embodiment of the present invention will be described. In addition, the same code | symbol is attached | subjected to the structure similar to 1st, 2nd embodiment, and description is abbreviate | omitted.

  As shown in FIGS. 19 and 20, in the inkjet recording apparatus 400 of the present embodiment, the first application unit 252 and the second application are provided on the downstream side of the driven roll 27 in the belt rotation direction and on the upstream side of the driven roll 29 in the belt rotation direction. A unit 254 and a third coating unit 256 are disposed to face the outer peripheral surface of the conveyor belt 28. The first coating unit 252 is disposed at the center in the width direction of the transport belt 28, and the second coating unit 254 and the third coating unit 256 are disposed at one end and the other end of the transport belt 28 in the width direction, respectively. ing. The first application unit 252, the second application unit 254, and the third application unit 256 are oil application rolls having a length that is about 1/3 of the width of the conveyance belt 28 and the same length as the paper P having the minimum width. 258.

  Here, the amount of silicone oil applied to the conveyor belt 28 by the first application unit 252, the second application unit 254, and the third application unit 254 can be adjusted, and the silicone oil at the center in the width direction of the conveyor belt 28 is adjustable. It is possible to change the amount of silicone oil applied to each portion of the conveyor belt 28 in the width direction, for example, by reducing the amount of toner applied and increasing the amount of silicone oil applied at both ends of the conveyor belt 28 in the width direction.

  Accordingly, the amount of silicone oil applied is increased in the severe range of the conveyance belt 28 in the width direction, and the cleaning performance is increased. On the other hand, in the range of little contamination in the width direction of the conveyance belt 28, the amount of silicone oil is increased. It is possible to reduce the amount of silicone oil consumed by reducing the coating amount.

  Next, a fourth embodiment of the present invention will be described. In addition, the same code | symbol is attached | subjected to the structure similar to 1st thru | or 3rd embodiment, and description is abbreviate | omitted.

  As shown in FIG. 21, the ink jet recording apparatus 500 of this embodiment includes an oil discharge head 222. The oil discharge head 222 is disposed on the upstream side of the recording head 32 in the belt rotation direction and on the downstream side of the surface potential sensor 13 in the belt rotation direction so as to face the outer peripheral surface of the conveyance belt 28.

  The oil application unit 220 is controlled by a control unit 502 that controls the entire inkjet recording apparatus 500. When the control unit 502 receives a print command, the oil application unit 220 is driven to apply silicone oil toward the outer peripheral surface of the conveyance belt 28. Discharge. As a result, a silicone oil film is formed on the outer peripheral surface of the conveyor belt 28.

  Here, there is a difference in the ejection amount during dummy jet between the nozzle that ejects ink during the image formation of the recording head 32 and the nozzle that does not eject, and the nozzle that ejects a large amount of ink during the image formation of the recording head 32 and a small amount. There is a case in which control is performed to make a difference in the discharge amount during dummy jets with nozzles that only discharge. In this case, also in the oil discharge head 222, the oil discharge amount at the time of the dummy jet is different for each nozzle.

  That is, for the nozzle of the oil discharge head 222 aligned in the belt rotation direction with the nozzle having a large discharge amount at the time of the dummy jet of the recording head 32, the discharge amount of silicone oil at the time of the dummy jet is increased and the dummy jet of the recording head 32 is increased. With respect to the nozzles of the oil discharge head 222 that are arranged in the belt rotation direction with a small or zero nozzle, the silicone oil discharge amount is reduced or the silicone oil discharge is not performed. Thereby, useless discharge of silicone oil from the oil discharge head 222 can be suppressed.

  Further, the amount of silicone oil discharged during the dummy jet of the oil discharge head 220 can be adjusted in four stages, and according to the number of recording heads 32 used among the YMCK four-color recording heads 32. The amount of silicone oil discharged from the oil discharge unit 222 is increased or decreased.

  That is, the unused recording head 32 performs a dummy jet, and the more unused recording heads 32, the smaller the amount of ink ejected onto the transport belt 28. In such a case, the oil ejection In this case, the discharge amount of silicone oil during the dummy jet of the head 222 is reduced, and the smaller the number of unused recording heads 32, the greater the amount of ink discharged onto the conveyor belt 28. Increases the discharge amount of silicone oil during the dummy jet of the oil discharge head 222.

  Furthermore, the amount of silicone oil discharged during the image formation of the oil discharge head 222 can be adjusted depending on whether monochrome printing or full color printing is performed, and the amount of silicone oil discharged from the oil discharge head 220 is It is reduced during monochrome printing and increased during full color printing.

  Next, a fifth embodiment of the present invention will be described. In addition, the same code | symbol is attached | subjected to the structure similar to 1st thru | or 4th embodiment, and description is abbreviate | omitted.

  As shown in FIG. 22, the ink jet recording apparatus 600 of the present embodiment is provided with a contact / separation mechanism 602 that contacts and separates the oil application unit 64 with respect to the outer peripheral surface of the conveyor belt 28. The contact / separation mechanism 602 is controlled by a control unit 604 that controls the entire inkjet recording apparatus 600.

  The control unit 604 causes the recording head 32 to perform a dummy jet to a predetermined range between the paper P and the paper P of the transport belt 28, but before that, the predetermined range in which the dummy jet is performed is transported to the oil application roll 70. Immediately before passing between the belt 28 and the belt 28, the contact / separation mechanism 602 is driven to move the oil application unit 64 toward the conveyance belt 28, and the oil application roll 70 and the application amount adjustment blade 72 are brought into contact with the conveyance belt 28. . Then, when a predetermined range where the dummy jet is performed passes through the application amount adjusting blade 72, the control unit 604 drives the contact / separation mechanism 602 to move the oil application unit 64 to the side opposite to the conveying belt 28, and the oil application roll 70 In addition, the coating amount adjusting blade 72 is separated from the conveying belt 28.

  That is, the silicone oil is applied only to a predetermined range where the dummy jet between the paper P and the paper P of the conveying belt 28 is performed, and the silicone oil is not applied to the other range. Thereby, useless consumption of silicone oil can be suppressed. Further, since the silicone oil on the conveying belt 28 is not absorbed by the paper P, the silicone oil can be saved by that amount.

  When the above-described oil discharge head 220 is used, it is possible to perform the same operation as in the present embodiment in which silicone oil is applied only to a predetermined range on the conveyor belt 28 only with or without discharge.

  Next, a sixth embodiment of the present invention will be described. In addition, the same code | symbol is attached | subjected to the structure similar to 1st Embodiment, and description is abbreviate | omitted.

  As shown in FIGS. 23 and 24, the ink jet recording apparatus 100 as the droplet discharge apparatus of the present embodiment has four colors of ink of yellow (Y), magenta (M), black (K), and cyan (C). Thus, the full-color printer forms a full-color image on the paper P. The ink jet recording apparatus 100 is a printer using a so-called offset printing method, and the recording head array 30 ejects ink toward an intermediate transfer drum 14 as a carrier and temporarily forms an ink image on the intermediate transfer drum 104. And an ink image is transferred from the intermediate transfer drum 104 to the paper P.

  A paper feed tray 16 is provided at the bottom of the ink jet recording apparatus 100 so that it can be inserted and removed. Sheets P are stacked on the sheet feeding tray 16, and a pickup roll 18 is in contact with the uppermost sheet P. The paper P is fed one by one from the paper feed tray 16 to the downstream side in the transport direction by the pick-up roll 18, and the image forming unit is configured by the transport rolls 109, 120, 121, 123, 125 arranged in order along the transport path. Sheet 122 is fed. The transport rolls 123 and 125 are star wheels that are in contact with the surface on which the ink image of the paper P is transferred.

  In the image forming unit 122, the intermediate transfer drum 104 is disposed facing the conveyance path, the recording head array 30 is disposed above the intermediate transfer drum 104, and the maintenance unit 34 is brought close to the recording head array 30. ing.

  As shown in FIG. 23, the recording head array 30 approaches the intermediate transfer drum 14 when ink droplets are ejected. Further, as shown in FIG. 24, the recording head array 30 secures a space for the maintenance unit 34 to enter the intermediate transfer drum 14 away from the intermediate transfer drum 14 during maintenance.

  As shown in FIG. 23, the maintenance unit 34 retreats to the outside of the ejection area SE where ink droplets are ejected from the recording head array 30 during image formation. Also, as shown in FIG. 25, the maintenance unit 34 enters the ejection area SE during non-image formation.

  Further, as shown in FIGS. 23 and 24, on the conveyance path side of the intermediate transfer drum 104, a charging roll 128 as a transfer unit, a static elimination roll 130 as a transfer unit, and a peeling claw 132 are sequentially arranged from the upstream side in the conveyance direction. It is in contact. The charging roll 128 conveys the paper P while pressing it against the intermediate transfer drum 104 and applies a charge to the paper P, thereby electrostatically attracting the paper P to the intermediate transfer drum 104 and transferring the ink image onto the paper P. Further, the static elimination roll 130 removes the charge of the paper P while transporting the paper P, thereby releasing the electrostatic adsorption between the paper P and the intermediate transfer drum 104. The peeling claw 132 peels the paper P from the intermediate transfer drum 104.

  And conveyance roll 127,129,131,133,135,137,139 is arrange | positioned in the conveyance direction downstream of the peeling nail | claw 132 from the conveyance direction upstream. The transport rolls 127, 133, 135, 137, and 139 have a star wheel that is in contact with the surface on which the ink image of the paper P is transferred, and contact between the surface of the paper P on which the ink image is transferred and the roll. Is decreasing.

  A paper discharge tray 46 is disposed above the ink tank 35, and a transport roll 139 is disposed on the side of the paper discharge tray 46. That is, the paper P is discharged onto the paper discharge tray 46 by the transport roll 139.

  As shown in FIG. 25, a drum cleaning unit 148 is disposed downstream of the peeling claw 132 in the rotational direction of the intermediate transfer drum 14 and upstream of the recording head array 30 in the rotational direction of the intermediate transfer drum 14. The drum cleaning unit 148 contacts the peripheral surface of the intermediate transfer drum 104 and scrapes ink remaining on the intermediate transfer drum 104 without being transferred onto the paper P, and a cleaning blade 49 as a cleaning member. A recovery box 51 for recovering ink and the like scraped off from the intermediate transfer drum 104, and a blade adjustment mechanism 80. Note that an absorber 53 is spread on the bottom of the collection box 51 and absorbs liquid dropped from the cleaning blade 49.

  An oil application unit 164 is disposed downstream of the cleaning blade 49 in the rotational direction of the intermediate transfer drum 14 and upstream of the recording head array 30 in the rotational direction of the intermediate transfer drum 14. The oil application unit 164 includes a case 68, an oil application roll 70 as an application member that is rotatably supported by the case 68, an application amount adjustment blade 72, and a blade adjustment mechanism 82. The oil application roll 70 is in pressure contact with the intermediate transfer drum 104 and rotates following the intermediate transfer drum 104. The oil application roll 70 is formed of a porous material such as polyethylene or urethane, impregnated with silicone oil, and applies the silicone oil to the intermediate transfer drum 104.

  On the other hand, the ink ejected from the recording head 32 is a water-based ink. For this reason, the ink aggregates due to the water repellent effect of the silicone oil film on the intermediate transfer drum 104. Accordingly, it is possible to suppress an increase in the force with which the ink adheres to the intermediate transfer drum 104, and the ink is easily peeled from the intermediate transfer drum 104 when the intermediate transfer drum 104 is cleaned by the cleaning blade 49.

  The oil application roll 70 may be a drive roll. In this case, the oil application roll 70 can be prevented from slipping with respect to the intermediate transfer drum 104.

Here, since the coating liquid needs to spread wet on the intermediate transfer drum 104, the relationship of the following formula (A) is required. However, as shown in FIG. 26, the surface tension of the coating liquid T is γ ₀ , and the critical surface tension γ _b of the intermediate transfer drum 104 is set.

γ ₀ <γ _b (A)

Further, in order to give the coating solution water repellency, the relationship of the following formula (B) is required. However, the surface tension of the ink I is γ _i .

γ ₀ <γ _i (B)

  Accordingly, as in the first embodiment, the ink I does not spread on the film of the coating liquid T and aggregates, so that the ink on the intermediate transfer drum 104 is easily scraped off by the cleaning blade 49.

  Further, as shown in FIG. 25, the application amount adjusting blade 72 is in contact with the intermediate transfer drum 104 on the downstream side in the drum rotation direction with respect to the oil application roll 70, and an excess amount of silicone oil applied to the intermediate transfer drum 104. Is scraped off to make the thickness of the silicone oil a predetermined thickness.

  The cleaning state varying unit 15 as the cleaning state varying unit and the contact state varying unit includes blade adjustment mechanisms 80 and 82. The blade adjusting mechanism 80 supports the cleaning blade 49 so as to be movable toward the intermediate transfer drum 104 side and the counter intermediate transfer drum 104 side, and moves to the intermediate transfer drum 104 side to increase the amount of biting into the intermediate transfer drum 104. Let As a result, the cleaning blade 49 increases the amount of force that the ink is scraped off from the intermediate transfer drum 104. Further, the blade adjustment mechanism 80 moves the cleaning blade 49 to the anti-intermediate transfer drum 104 side to reduce the amount of biting into the intermediate transfer drum 104, whereby the friction force of the cleaning blade 49 with the intermediate transfer drum 104 is reduced. And the wear of the cleaning blade 49 is reduced.

  Further, the blade adjustment mechanism 82 supports the coating amount adjustment blade 72 so as to be movable toward the intermediate transfer drum 104 side and the anti-intermediate transfer drum 104 side, and moves to the intermediate transfer drum 104 side to move to the intermediate transfer drum 104 side. Increase the amount of bite. As a result, the amount by which the coating amount adjusting blade 72 scrapes ink from the intermediate transfer drum 104 decreases, and the amount of silicone oil applied to the intermediate transfer drum 103 increases. Further, the blade adjustment mechanism 82 moves the application amount adjustment blade 72 toward the anti-intermediate transfer drum 104 side to reduce the amount of biting into the intermediate transfer drum 104. As a result, the amount by which the coating amount adjusting blade 72 scrapes ink from the intermediate transfer drum 104 increases, and the amount of silicone oil applied to the intermediate transfer drum 104 decreases.

  In the first to sixth embodiments, the present invention has been described by taking an inkjet recording apparatus as an example. However, the present invention is not limited to an inkjet recording apparatus, and the display is performed by discharging colored ink onto a polymer film. The present invention can be applied to a general liquid droplet ejection apparatus for various industrial uses such as production of a color filter for liquid crystal and formation of an EL display panel by discharging an organic EL solution onto a substrate.

  In addition, the “recording medium” that is a target of image recording in the droplet discharge device of the present invention includes a wide range of objects as long as the droplet discharge head discharges droplets. Accordingly, the recording medium includes recording paper, an OHP sheet, and the like, but also includes, for example, a polymer film.

  The “droplet ejection head” in the droplet ejection apparatus of the present invention includes a wide range of means for ejecting droplets toward a recording medium or a carrier. For example, an ink jet recording head that ejects ink droplets while moving in the width direction of the paper P and shorter than the width of the paper P is included.

  In addition, the “rotating body” in the droplet discharge device of the present invention includes a wide range of members as long as the liquid discharged from the droplet discharge head adheres thereto. For example, a drum that holds and rotates a recording medium, an intermediate transfer belt, and the like are included.

  Further, the “cleaning member” in the droplet discharge device of the present invention includes a wide range of members as long as they are members that clean the droplets adhering to the transport member. For example, a cleaning roll that rotates in contact with the transport member and absorbs droplets, a movable blade that contacts the transport member and moves in a direction intersecting the transport direction, and the like are included.

  In addition, the “coating member” in the liquid droplet ejection apparatus of the present invention includes a wide range of members that apply a coating liquid having a property of repelling liquid droplets ejected from a liquid droplet ejection head to a rotating body. Examples include a web that is impregnated with the coating liquid and is in contact with the conveying member, and a roll that is impregnated with or held on the surface of the coating liquid and moves in a direction crossing the conveying direction by contacting the rotating body.

  Further, the “charging means” in the droplet discharge apparatus of the present invention includes a wide range of means as long as they are means for charging the conveying member. For example, a corotron for charging the conveying member in a non-contact manner is included.

  Furthermore, in the first to sixth embodiments, the downstream end of the cleaning blade 49 or the coating amount adjusting blade 72 in the belt rotation direction or the drum rotation direction is brought into contact with the transport belt 28 or the intermediate transfer drum 104. Alternatively, the upstream end of the coating amount adjusting blade 72 in the belt rotation direction or the drum rotation direction may be brought into contact with the conveyance belt 28 or the intermediate transfer drum 104.

  Here, the cleaning blade 49 and the coating amount adjusting blade 72 are worn by bringing the downstream end of the cleaning blade 49 and the coating amount adjusting blade 72 in the belt rotating direction or the drum rotating direction into contact with the conveying belt 28 or the intermediate transfer drum 104. On the other hand, by bringing the upstream end of the cleaning blade 49 or the coating amount adjusting blade 72 in the belt rotation direction or drum rotation direction into contact with the transport belt 28 or the intermediate transfer drum 104, the blade cleaning ability can be improved.

1 is a side view illustrating an outline of an ink jet recording apparatus according to a first embodiment of the present invention. 1 is a side view illustrating an outline of an ink jet recording apparatus according to a first embodiment of the present invention. It is a side view which shows the outline of the printing part of the inkjet recording device of 1st Embodiment of this invention. FIG. 3 is an enlarged cross-sectional view illustrating a conveyance belt provided in the ink jet recording apparatus according to the first embodiment of the present invention. (A), (B) is sectional drawing which shows the cleaning unit with which the inkjet recording device of 1st Embodiment of this invention was equipped. (A), (B) is sectional drawing which shows the oil application | coating unit with which the inkjet recording device of 1st Embodiment of this invention was equipped. It is a graph which shows the relationship between an applied voltage and the surface potential of a conveyance belt. 3 is a flowchart for explaining a method of adjusting the amount of silicone oil applied to the cleaning blade and the conveyance belt during printing in the ink jet recording apparatus according to the first embodiment of the present invention. 6 is a flowchart for explaining a method for adjusting the amount of silicone oil applied to the cleaning blade and the conveyor belt when the cleaning mode is performed in the ink jet recording apparatus according to the first embodiment of the present invention. It is a side view which shows the outline of the printing part of the inkjet recording device of 1st Embodiment of this invention. It is sectional drawing which shows the modification of the blade adjustment mechanism with which the inkjet recording device of 1st Embodiment of this invention was equipped. It is sectional drawing which shows the 1st modification of the oil application unit with which the inkjet recording device of 1st Embodiment of this invention was equipped. 6 is a flowchart for explaining a method of adjusting the amount of silicone oil applied to the cleaning blade and the conveyance belt in the ink jet recording apparatus according to the first embodiment of the present invention. It is sectional drawing which shows the 2nd modification of the oil application unit with which the inkjet recording device of 1st Embodiment of this invention was equipped. It is a side view which shows the outline of the printing part of the inkjet recording device of 2nd Embodiment of this invention. It is a flowchart for demonstrating the adjustment method of the application quantity of the silicone oil to the conveyance belt in the inkjet recording device of 2nd Embodiment of this invention. (A), (B) is sectional drawing which expanded and showed the conveyance belt with which the inkjet recording device of 2nd Embodiment of this invention was equipped. It is a flowchart for demonstrating the adjustment method of the application quantity of the silicone oil to the conveyance belt in the inkjet recording device of 2nd Embodiment of this invention. It is a side view which shows the outline of the printing part of the inkjet recording device of 3rd Embodiment of this invention. It is a top view which shows the printing part of the inkjet recording device of 3rd Embodiment of this invention from the lower side. It is a side view which shows the outline of the printing part of the inkjet recording device of 4th Embodiment of this invention. It is a side view which shows the outline of the printing part of the inkjet recording device of 5th Embodiment of this invention. It is a side view which shows the outline of the inkjet recording device of 6th Embodiment of this invention. It is a side view which shows the outline of the inkjet recording device of 6th Embodiment of this invention. It is a side view which shows the outline of the printing part of the inkjet recording device of 7th Embodiment of this invention. It is sectional drawing which expands and shows the intermediate transfer drum with which the inkjet recording device of 7th Embodiment of this invention was equipped. (A), (B) is sectional drawing which shows the mode of cleaning of the conveyance belt in the conventional inkjet recording device.

Explanation of symbols

12 Inkjet recording device (droplet ejection device)
13 Surface potential sensor (dirt level detection means, current value detection means)
15 Cleaning state variable part (contact state variable means, cleaning state variable means)
28 Conveying belt (rotary body, conveying member)
32 Inkjet recording head (droplet ejection head)
36 Charging roll (charging means)
39 Ammeter (dirt level detection means, current value detection means)
49 Blade (cleaning member)
70 Oil application roll (application member)
100 Inkjet recording device (droplet ejection device)
104 Intermediate transfer drum (support)
226 Temperature / humidity sensor (environment detection means)
230 Treatment Liquid Discharge Head 300 Inkjet Recording Device (Droplet Discharge Device)
400 Inkjet recording device (droplet ejection device)
500 Inkjet recording device (droplet ejection device)
600 Inkjet recording device (droplet ejection device)
P paper (recording medium)

Claims (10)

A droplet discharge head for discharging droplets;
A conveying member that conveys a recording medium to face the droplet discharge head ;
A cleaning member that contacts the transport member and cleans the transport member ;
An application member for applying an application liquid having a property of repelling liquid discharged from the droplet discharge head to the transport member ;
When the length in the direction orthogonal to the conveyance direction of the recording medium conveyed by the conveyance member is smaller than the maximum print width of the droplet discharge head , the contact pressure of the cleaning member to the conveyance member is increased. Or cleaning state variable means for increasing the amount of coating liquid applied to the transport member by the coating member;
A droplet discharge apparatus comprising: Having a dirt level detecting means for detecting the dirt level of the conveying member;
The cleaning state variable means increases the contact pressure of the cleaning member to the conveying member before the dirt level of the conveying member detected by the dirt level detecting means exceeds an allowable range, or the application member. The liquid droplet ejection apparatus according to claim 1, wherein an application amount of the coating liquid to the transport member is increased . It has environment detection means for detecting at least one of the temperature and humidity of the environment around the transport member,
When the temperature detected by the environment detection unit is higher than a threshold value and the humidity is lower than the threshold value, the cleaning state variable unit increases the contact pressure of the cleaning member to the transfer member, and applies the application member to the transfer member. 3. The liquid according to claim 1, wherein at least one of increasing the coating amount of the coating liquid and decreasing the viscosity of the coating liquid applied to the transport member by the coating member is performed. Drop ejection device. The cleaning condition varying means any of claims 1 to 3, characterized in that increasing the coating amount of the coating liquid to the conveying member by the applying member with more range of stains in the rotation axis direction of the conveying member The droplet discharge device according to claim 1. The cleaning state variable means increases the application amount of the coating liquid onto the transport member by the application member within a range in which the liquid discharge amount of the droplet discharge head in the rotation axis direction of the transport member is large. The droplet discharge device according to any one of claims 1 to 3 . A plurality of the droplet discharge heads are arranged in the rotation direction of the transport member,
As the number of droplet discharge heads that discharge droplets increases, the cleaning state varying means increases the contact pressure of the cleaning member to the transport member and the amount of coating liquid applied to the transport member by the coating member. 6. The droplet discharge device according to claim 1 , wherein at least one of the number of the droplets is increased . Monochrome printing mode and full color printing mode can be selected,
The cleaning state varying means increases at least one of a contact pressure of the cleaning member with the transport member and an application amount of the coating liquid onto the transport member by the application member when a full color printing mode is selected. the apparatus according to any one of claims 1 to 6, characterized in. A treatment liquid discharge head for discharging a treatment liquid containing a flocculant for aggregating the liquid;
The cleaning state varying means is configured to at least one of a contact pressure of the cleaning member with the transport member and an application amount of the coating liquid onto the transport member by the application member when the processing liquid discharge head discharges the processing liquid. The liquid droplet ejection apparatus according to claim 1 , wherein the liquid droplet ejection apparatus according to claim 1 is increased . Having charging means for charging the conveying member;
The droplet discharge apparatus according to claim 2, wherein the dirt level detection unit is a surface potential detection unit that detects a surface potential of the transport member . Having charging means for charging the conveying member;
3. The droplet discharge device according to claim 2, wherein the contamination level detection unit is a current value detection unit that detects a current value supplied to the charging unit .

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