Patent Grant
12197162
This application is based on and claims priority under 35 USC 119 from Japanese Patent Application No. 2023-004080 filed Jan. 13, 2023.
The present invention relates to a cleaning device that cleans hot-melt powder remaining on an object-to-be-cleaned, and a powder processing apparatus using the cleaning device.
In the related art, as a cleaning device of this type, for example, devices described in JP2007-163611A (DETAILED DESCRIPTION and
JP2007-163611A (DETAILED DESCRIPTION and
JP1993-307346A (Example and
In JP2018-054646A (DETAILED DESCRIPTION and
Aspects of non-limiting embodiments of the present disclosure relate to a cleaning device in which in cleaning a hot-melt powder remaining on an object-to-be-cleaned by an elastic plate-shaped cleaning unit, even in a low temperature environment in which the cleaning unit is likely to be cured, a good contact state of the cleaning unit with the object-to-be-cleaned is maintained and a deterioration of cleaning performance by the cleaning unit is improved, and a powder processing apparatus using the cleaning device.
Aspects of certain non-limiting embodiments of the present disclosure overcome the above disadvantages and/or other disadvantages not described above. However, aspects of the non-limiting embodiments are not required to overcome the disadvantages described above, and aspects of the non-limiting embodiments of the present disclosure may not overcome any of the disadvantages described above.
According to an aspect of the present disclosure, there is provided a cleaning device including: an elastic plate-shaped cleaning unit that has a tip portion disposed in contact with a surface of an object-to-be-cleaned which moves in a predetermined direction, is provided to be inclined in a direction facing a moving direction of the object-to-be-cleaned, and cleans hot-melt powder remaining on the object-to-be-cleaned; a facing unit that is disposed in contact with a back surface side of the object-to-be-cleaned and is provided to face the cleaning unit across the object-to-be-cleaned; and a heating unit that heats a contact portion of the cleaning unit to a temperature lower than a softening point of the powder by heating the facing unit.
Exemplary embodiment(s) of the present invention will be described in detail based on the following figures, wherein:
In
The cleaning device of this type is incorporated in a powder processing apparatus including a processing unit (not shown) that performs a predetermined process using the hot-melt powder 6, and cleans the powder 6 remaining on the object-to-be-cleaned 5 that moves in a predetermined direction.
In such technical units, the object-to-be-cleaned 5 is not limited to the object that circulates and rotates, and includes an object that moves in one direction. Further, the present invention is not limited to an image holding unit (photoreceptor, intermediate transfer body, or the like) that holds an image by the powder 6, and also broadly includes a transfer member of a transfer device to which the powder 6 adheres.
Further, the powder 6 is not limited to, for example, a toner used as an image forming powder in an electrophotographic method, and broadly includes coating particles as a coating powder. In this case, the powder 6 often contains the external additive 6a widely. The external additive 6a adheres to the surface of the powder 6 and controls chargeability, fluidity, and the like of the powder 6.
Further, the cleaning unit 1 may be an elastic plate-shaped unit, and a cleaning member made of an elastic material may be supported on the support bracket, or widely includes those having a plate-shaped cleaning member using an elastic material such as rubber via a metal base material for the support bracket. In addition, in the present exemplary embodiment, it is needless to say that a device provided with a cleaning unit (for example, a brush-shaped cleaning member) having an aspect different from the cleaning unit 1 is also applied.
Further, there is a method of preventing the powder 6 from slipping by supplying a band-shaped image (toner band) of the powder (for example, toner) periodically or irregularly to the edge portion of the cleaning unit 1, and forming a dam (reservoir portion) by the external additive 6a contained in the powder 6. Although this method is based on the premise that the contact state of the cleaning unit 1 is poor and compensates for the poor contact state, excessive consumption of the powder 6 may occur. However, in the present exemplary embodiment, although it is not necessary to use this method, it is possible to use this method in combination.
Further, the facing unit 2 may be a separate body from the object-to-be-cleaned 5, or may be provided integrally. Further, in an aspect in which the facing unit 2 is a separate body, the facing unit 2 may be a rotating body that rotates following the movement of the object-to-be-cleaned 5, or includes any non-rotating body that does not rotate following the movement. Further, in addition to an aspect in which the facing unit 2 faces a contact portion region of the cleaning unit 1, there is an aspect in which the facing unit 2 faces the cleaning unit 1 at a position close to the cleaning unit 1 without facing the contact portion region of the cleaning unit 1.
Further, the heating unit 3 heats the tip portion of the cleaning unit 1 in order to prevent the tip portion of the cleaning unit 1 from being easily cured, for example, in a low temperature environment. Here, the heating unit 3 broadly includes the facing unit 2 as a heating target. Further, it is necessary to heat the contact portion of the cleaning unit 1 in a range lower than the softening point of the powder 6. In a case where the contact portion of the cleaning unit 1 is heated to a temperature equal to or higher than the softening point of the powder 6, the powder 6 may melt and the cleaning performance may be impaired.
As described above, in the cleaning device of the present exemplary embodiment, even in a low temperature environment, the tip portion of the cleaning unit 1 is softened by heating the facing unit 2, and a good contact state of the cleaning unit 1 with the object-to-be-cleaned 5 is maintained. Therefore, even in a case where the powder 6 is not supplied to the tip portion of the cleaning unit 1 periodically or irregularly, a dam caused by the external additive 6a contained in the powder 6 is secured at the tip portion of the cleaning unit 1, and the slip-through of the powder 6 is prevented. Further, since only the tip portion of the cleaning unit 1 is heated, a required heating temperature is low, and the powder 6 to be cleaned does not melt.
Next, for example, a representative aspect or a preferable aspect of the cleaning device according to the present exemplary embodiment will be described.
First, as a typical aspect of the heating unit 3, there is an aspect in which the facing unit 2 is heated to a temperature lower than the softening point of the powder 6. In this way, for example, it is preferable to control the heating temperature of the facing unit 2, because the contact portion of the cleaning unit 1 with the object-to-be-cleaned 5 is prevented from reaching a temperature equal to or higher than the softening point of the powder 6.
Further, from a viewpoint of maintaining good heat transferability of the heating unit 3, for example, an aspect is preferable in which the heating unit 3 heats the facing unit 2 in contact with the facing unit 2.
The followings are typical aspects of the present example.
(1) An aspect in which the facing unit 2 has a hollow portion, and the heating unit 3 is provided in the hollow portion.
(2) An aspect in which the heating unit 3 is disposed in contact with the surface of the facing unit 2.
(3) An aspect in which the facing unit 2 has a roll body made of a synthetic resin around a shaft made of metal, and the heating unit 3 heats the facing unit 2 in contact with both ends of the shaft made of metal.
Further, from a viewpoint that the heating unit 3 does not have a dedicated heat source, it is also possible to locally heat the facing unit 2 in a non-contact state by using the heat from another heat source.
As a typical aspect of the present example, an aspect is mentioned in which the heating unit 3 has an air flow unit (not shown) disposed between another heat source and the facing unit 2, and guides heat generated by the other heat source through the air flow unit to the facing unit 2.
Further, as a typical layout of the facing unit 2, an aspect in which the facing unit 2 is disposed to face the contact portion region of the cleaning unit 1 may be mentioned.
In the present example, in a case where the facing unit 2 moves in a state of being in contact with the object-to-be-cleaned 5, in order to maintain a relative positional relationship between the facing unit 2 and the cleaning unit 1, for example, it is preferable that the cleaning unit 1 moves following the movement of the facing unit 2.
Further, there is an aspect in which the facing unit 2 may be disposed to face the cleaning unit 1 at a position close to the contact portion region of the cleaning unit 1. In this case, since the facing unit 2 does not face the contact portion region of the cleaning unit 1, the amount of heat of the facing unit 2 heated by the heating unit 3 is transferred to the contact portion region of the cleaning unit 1 through the object-to-be-cleaned 5, and it is necessary that the contact portion region of the cleaning unit 1 is indirectly heated. Therefore, the term “close position” as used herein means a position sufficiently close to transfer the heat of the facing unit 2 to the contact portion region of the cleaning unit 1 in consideration of the thermal conductivity of the object-to-be-cleaned 5 and the like.
Further, in the powder processing apparatus including the cleaning device described above, for example, it is preferable to efficiently operate the heating unit 3 in a low temperature environment in which the cleaning unit 1 is likely to be cured. In this case, a temperature detecting unit (not shown) that detects the ambient environment temperature of the object-to-be-cleaned 5 and a control unit (not shown) that operates the heating unit 3 of the cleaning device in a case where the temperature detecting unit reaches a predetermined low temperature environment temperature condition may be provided.
Hereinafter, the present invention will be described in more detail on the basis of the exemplary embodiments shown in the accompanying drawings.
Overall Configuration of Image Forming Apparatus
In
In the present example, in the image forming engine 30, image forming units 31 (specifically, 31a to 31d) that forms the image of the plurality of colors are arranged in a substantially horizontal direction, a transfer module 40 including, for example, a belt-shaped intermediate transfer body 45 that circulates and moves along the arrangement direction of the image forming unit 31 is disposed above the image forming unit 31, and an image of each color formed by each of the image forming units 31 is transferred to the medium via the transfer module 40.
In the present exemplary embodiment, as shown in
Reference numerals 37 (specifically, 37a to 37d) indicate toner cartridges for supplying the color component toners to the corresponding developing devices 35.
Further, in the present exemplary embodiment, the transfer module 40 includes the belt-shaped intermediate transfer body 45 made of, for example, a polyimide resin spanned over a plurality of tension rolls 41 to 44, and for example, the tension roll 41 is used as a drive roll to circulate and move the intermediate transfer body 45. A transfer device (transfer roll in this example) 46 for primary transfer is disposed on a back surface of the intermediate transfer body 45 corresponding to the photoconductor 32 of each of the image forming units 31, and by applying a transfer voltage having a polarity opposite to a charging polarity of the toner to the transfer device 46, the toner image on the photoconductor 32 is electrostatically transferred to the intermediate transfer body 45 side.
Furthermore, a cleaning device 47 for the intermediate transfer body is disposed upstream of the image forming unit 31a on the most upstream side of the intermediate transfer body 45 to remove the residual toner on the intermediate transfer body 45.
In the present exemplary embodiment, the transfer device 60 for secondary transfer is disposed at a portion corresponding to the tension roll 42 downstream of the image forming unit 31d on the most downstream side of the intermediate transfer body 45 such that a primary transfer image on the intermediate transfer body 45 is secondarily transferred (collectively transferred) to the medium.
In the present example, the transfer device 60 includes a secondary transfer roll 61 disposed in pressure contact with the toner image holding surface side of the intermediate transfer body 45, and a backup roll (also serving as the tension roll 42 in the present example) that is disposed on the back surface side of the intermediate transfer body 45 and forms the counter electrode of the secondary transfer roll 61. For example, the secondary transfer roll 61 is grounded, and a secondary transfer voltage having the same polarity as the charging polarity of the toner is applied to the backup roll (the tension roll 42).
Further, a supply roll 51 that supplies the medium is provided in the medium supply apparatus 50, a transfer roll (not illustrated) is disposed in the medium conveying path 55, and a positioning roll 56 that supplies the medium to a secondary transfer portion at a predetermined timing is disposed in the medium conveying path 55 located immediately before the secondary transfer portion.
Furthermore, a fixing device 70 is provided in the medium conveying path 55 located downstream of the secondary transfer portion, and the fixing device 70 includes, for example, a heating fixing roll 71 having a built-in heater (not shown) is embedded, and a pressurizing fixing roll 72 that is arranged in pressure contact with the heating fixing roll 71 to rotate following the heating fixing roll 71. A discharge roll 57 that discharges the medium in the apparatus housing 21 is provided downstream of the fixing device 70 to sandwich, convey, and discharge the medium, and the medium is accommodated in a medium storage receiver 58 formed on the upper portion of the apparatus housing 21.
Although not illustrated in the present example, of course, a manual supply apparatus for medium or a double-sided recording module capable of double-sided recording of the medium may be separately provided.
Cleaning Device for Intermediate Transfer Body
Basic Configuration of Cleaning Device
In the present example, as illustrated in
In the present example, the cleaning device 47 includes an facing roll 110 (corresponding to the facing unit 2 shown in
Configuration Example of Cleaning Member
In the present example, as shown in
In the present example, the cleaning member 101 is disposed to be inclined such that the tip end side toward the intermediate transfer body 45 side faces the movement direction of the intermediate transfer body 45, and the inclination angle is selected within a predetermined range with respect to the tangential direction of the contact portion with the intermediate transfer body 45.
In the present example, as schematically shown in
In the present example, the cleaning member 101 is configured by one plate-shaped member, but the present invention is not limited to this, and for example, a configuration in which a plurality of plate-shaped members are stacked may be used.
Relationship Between Facing Roll and Cleaning Member
Further, in the present example, although the cleaning member 101 is positioned on the cleaning container 100 as shown in
In the present example, since the facing roll 110 also serves as the tension roll 41 used as the drive roll, the position of the facing roll 110 may change instead of being fixed. However, in a case where the position of the tension roll 41 changes, the cleaning container 100 follows and moves via the intermediate transfer body 45 stretched over the tension roll 41, and along with this, the cleaning member 101 positioned in the cleaning container 100 follows and moves. Therefore, even in a case where the position of the facing roll 110 changes, the relative positional relationship between the cleaning member 101 and the facing roll 110 is maintained.
In the present example, the facing roll 110 also serves as the tension roll 41 used as a drive roll. However, the tension roll 41 may be a tension applying roll that applies tension to the intermediate transfer body 45. In this case, the position of the tension roll 41 changes in a case where the tension of the intermediate transfer body 45 is adjusted, but the cleaning member 101 moves following the movement of the facing roll 110.
Necessity of Heating Component
In the present example, since the cleaning member 101 is made of an elastic material using a rubber material, for example, in a low temperature environment, the nip pressure of the cleaning member 101 against the intermediate transfer body 45 may be reduced due to the curing of the rubber, the dam caused by the external additive 104 collapses, and the toner may slip through.
Therefore, in the present example, the heating component 120 for heating the edge portion E of the cleaning member 101 is adopted such that the rubber curing of the cleaning member 101 does not occur even in a low temperature environment.
Configuration Example of Heating Component
As shown in
In the present example, the heat generation resistance layer 121 is supplied with the heat generation current Ih from the energization circuit 151 based on the heating control signal HS from the control device 150, the heat generation resistance layer 121 generates heat, and the facing roll 110 is heated.
Other Configuration Examples of Heating Component
The heating component 120 is not limited to the one shown in
In
In the present example, in a case where the heat roll 122 generates heat, the heat of the heat roll 122 is transferred through the roll body 111, so that the surface of the facing roll 110 is heated.
In
In the present example, since the external heat roll 123 directly heats the surface of the facing roll 110, it is possible to increase the heat transfer efficiency as compared with a case where the facing roll 110 is heated from the inside. Further, in the present example, since the facing roll 110 has a structure having the hollow portion 113, the heat radiation efficiency is high, and it is effective in accelerating the temperature drop of the facing roll 110 in a case where the heating by the external heat roll 123 is stopped.
Cleaning Device Control System
In the present example, as shown in
The control device 150 is configured by a microcomputer including various types of processors. In the embodiments above, the term “processor” refers to hardware in a broad sense. Examples of the processor include general processors (e.g., CPU: Central Processing Unit) and dedicated processors (e.g., GPU: Graphics Processing Unit, ASIC: Application Specific Integrated Circuit, FPGA: Field Programmable Gate Array, and programmable logic device). In the embodiments above, the term “processor” is broad enough to encompass one processor or plural processors in collaboration which are located physically apart from each other but may work cooperatively. The order of operations of the processor is not limited to one described in the embodiments above, and may be changed.
Further, the control device 150 receives temperature information from an environment temperature sensor 152 as a temperature detecting unit that detects the temperature of the ambient environment of the intermediate transfer body 45, and the surface temperature sensor 153 that detects the surface temperature of the facing roll 110, in the vicinity of the facing roll 110.
In the present example, the upper limit of the target temperature Ta (see
Then, the control device 150 installs in advance a necessary program such as a “cleaning device heating control program (see
Heating Control Operation of Cleaning Device
As shown in
The term “in a low temperature environment” as used herein refers to a temperature environment condition in which the cleaning member 101 is cured to reach a poor contact state with the intermediate transfer body 45, and means a low temperature and low humidity environment, for example, a temperature of 10° C. or less and a humidity of 15% or less.
In the present example, the control device 150 determines whether or not the number of consecutive low-density images has reached a specified value N, for example, considering the status of past print jobs, in a low temperature environment, and under a condition that the number of consecutive low-density images has reached the specified value N, the control device 150 determines that the cleaning member 101 may be rolled up.
In this case, as shown in
In this state, the heat generation resistance layer 121 generates heat, heat from the heat generation resistance layer 121 is transferred to the surface of the facing roll 110 through the roll body 111, and the facing roll 110 is heated.
Here, since the control device 150 sets the target temperature Ta of the surface of the facing roll 110 to a temperature lower than the softening point of the toner, the facing roll 110 is heated until the surface of the facing roll 110 reaches the target temperature Ta. That is, since the surface of the facing roll 110 is detected by the surface temperature sensor 153, in a case where the surface temperature sensor 153 detects the target temperature Ta, the control device 150 stops the output of the heating control signal HS to the energization circuit 151, and the supply of the heat generation current Ih from the energization circuit 151 is stopped.
In this state, as shown in
Further, since the contact portion region of the edge portion E of the cleaning member 101 comes into contact with the remaining toner 103 at the temperature Tc, a situation in which the toner 103 to be cleaned is softened and adheres to the edge portion E of the cleaning member 101 does not occur.
In this way, in a case where the edge portion E of the cleaning member 101 reaches the desired temperature condition, the control device 150 starts the print job.
Then, the control device 150 performs on/off control of heating of the heat generation resistance layer 121 as the heating component 120 such that the surface of the facing roll 110 is maintained at the target temperature Ta.
After that, the control device 150 determines whether or not a heating release condition is reached. The term “heating release condition” as used herein refers to a condition in which the print job is completed, the environment is no longer in a low temperature environment, or the number of consecutive low-density images is less than the specified value N.
In a case where the control device 150 determines that the “heating release condition” is reached, the control device 150 stops the heating operation of the facing roll 110.
In a case where the environment is not in a low temperature environment, or the environment is in a low temperature environment but the number of consecutive low-density images does not reach the specified value N, the control device 150 ends a series of processes without performing a heating operation on the cleaning device 47.
In the present exemplary embodiment, the facing roll 110 is disposed to face the contact portion region of the edge portion E of the cleaning member 101, but the present invention is not limited to this, and as in the third modification form shown in
In the present example, the facing roll 110 is disposed to face the cleaning member 101 at a position close to the contact portion region of the edge portion E of the cleaning member 101. In the present example, the amount of heat of the facing roll 110 heated by the heating component 120 is transferred to the contact portion region of the edge portion E of the cleaning member 101 through the intermediate transfer body 45, and the contact portion region of the cleaning member 101 is indirectly heated.
In this case, assuming that the distance between the contact portion region of the edge portion E of the cleaning member 101 and the contact portion region of the facing roll 110 with the intermediate transfer body 45 is d, it is presumed that as the distance d increases, the heat loss increases by the increase of the distance d in the process of heat transfer through the intermediate transfer body 45. Therefore, in a case where the heat loss can be obtained within an allowable range (for example, 20% or less), it is considered that the positional relationship may be treated as an offset arrangement due to “close position”.
Here, the offset amount (corresponding to the distance d) is, for example, preferably 1 to 5 mm, although the offset amount depends on the member (thermal conductivity) and the configuration. In a case where the offset amount is large, the posture of the plate-shaped cleaning member 101 is not stable, and the cleaning performance may be deteriorated.
Next, in evaluating the performance of the cleaning device according to the present exemplary embodiment, the performance is compared with the performance of the cleaning device according to the first and second comparative forms.
The cleaning device 47′ according to a first comparative form does not include the heating component of the first exemplary embodiment.
In this case, under an environmental condition that is not a low temperature environment, as shown in
However, assuming a case where continuous printing of low-density images is performed in a low temperature environment, as shown in
In order to eliminate such a situation, as shown in
In
In the present example, for example, the heater 160 heats the support bracket 102 in a low temperature environment. In this case, as shown in
In the present example, the basic configuration of the cleaning device 47 includes the cleaning member 101, and the facing roll 110 that faces the cleaning member 101 across the intermediate transfer body 45, as in the first exemplary embodiment, but is different from the first exemplary embodiment in that as the heating component 120 that heats the facing roll 110, the facing roll 110 is locally heated in a non-contact state by using the heat of another heat source.
In the present example, as another heat source 130, as shown in
In particular, in the present example, the air exhaust duct 131 is disposed close to the lower side of the facing roll 110.
Therefore, in the present exemplary embodiment, the heat Q generated in the fixing device 70, which is another heat source 130, is discharged to the outside together with the air through the air exhaust duct 131, but while passing through the air exhaust duct 131, the heat Q heats the air in the vicinity of the upper part of the air exhaust duct 131. Therefore, when the heated air in the air exhaust duct 131 passes through the portion corresponding to the facing roll 110, the heated air heats the air in the region between the air exhaust duct 131 and the facing roll 110. As a result, the heated air 132 rises toward the facing roll 110 and is guided to locally heat the facing roll 110.
As described above, in the present example, it is possible to heat the facing roll 110 without using the dedicated heating component 120 as in the first exemplary embodiment.
In
In the present example, the transfer device 60 for secondary transfer uses the tension roll 42 facing the secondary transfer roll 61 across the intermediate transfer body 45 as a backup roll, the power supply roll 66 is disposed in contact with the backup roll, and a transfer power supply 67 is connected to the power supply roll 66 to apply a transfer bias.
Further, the cleaning device 140 has a cleaning container 141 that accommodates a residue on the coating tube 65 formed on the surface of the secondary transfer roll 61 as the object-to-be-cleaned 5 (see
Further, in the present example, the secondary transfer roll 61 has a roll body 63 made of a synthetic resin such as urethane foam around the rotating shaft 62 made of metal, and a coating tube 65 made of, for example, polyimide is provided on the surface of the roll body 63.
In particular, in the present example, the object-to-be-cleaned is the coating tube 65 of the secondary transfer roll 61.
Further, in the present example, the roll body 63 of the secondary transfer roll 61 functions as the facing roll 210 facing the cleaning member 142 across the coating tube 65, and the facing roll 210 is integrated with the coating tube 65, but also serves as an element of the cleaning device 140.
Further, in the present example, the facing roll 210 is provided with a heating component 120 (corresponding to the heating unit 3 shown in
The heating components 120, as shown in
As described above, in the present example, the cleaning device 140 applied to the transfer device 60 for secondary transfer is disclosed, and it is possible to properly clean the covering tube 65 of the secondary transfer roll 61 with the cleaning member 142 even when continuous printing low-density images in a low temperature environment.
(((1)))
A cleaning device comprising:
In the cleaning device according to (((1))),
In the cleaning device according to (((1))) or (((2)))),
In the cleaning device according to (((3)))),
In the cleaning device according to (((3)))),
In the cleaning device according to (((3)))),
In the cleaning device according to (((1))) or (((2)))),
In the cleaning device according to (((7)))),
In the cleaning device according to any one of (((1))) to (((8))),
In the cleaning device according to (((9)))),
In the cleaning device according to any one of (((1))) to (((8))),
A powder processing apparatus comprising:
In the powder processing apparatus according to (((12)))),
The foregoing description of the exemplary embodiments of the present invention has been provided for the purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise forms disclosed. Obviously, many modifications and variations will be apparent to practitioners skilled in the art. The embodiments were chosen and described in order to best explain the principles of the invention and its practical applications, thereby enabling others skilled in the art to understand the invention for various embodiments and with the various modifications as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the following claims and their equivalents.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2023-004080 | Jan 2023 | JP | national |
| Number | Name | Date | Kind |
|---|---|---|---|
| 20160313679 | Mukai | Oct 2016 | A1 |
| 20200249603 | Ishigaya | Aug 2020 | A1 |
| Number | Date | Country |
|---|---|---|
| H05-307346 | Nov 1993 | JP |
| 2007-163611 | Jun 2007 | JP |
| 2018-054646 | Apr 2018 | JP |
| Number | Date | Country | |
|---|---|---|---|
| 20240241473 A1 | Jul 2024 | US |
