Background

[0001] A printing device can deliver a print material to a print medium to form an image on the print medium. In some examples, a printing device can be an electrophotographic printing device that supplies a toner (which is a type of print material) to an electrostatic latent image formed on a photoreceptor to form a visible toner image on the photoreceptor. The electrophotographic printing device transfers the toner image to a print medium, and then fixes the transferred toner image to the print medium, to form an image on the print medium

Brief Description of the Drawings

[0002] Some implementations of the present disclosure are described with respect to the following figures.

[0003] FIG. 1 is a sectional schematic diagram of an image forming device according to some examples.

[0004] FIG. 2 is an enlarged view of a portion of a developer device including a developing roller, a regulating blade, and removable films adhered to the regulating blade, according to some examples.

[0005] FIG. 3 is a sectional view of a regulating blade and removable films adhered to surfaces of the regulating blade, according to some examples.

[0006] FIG. 4 is a side perspective view of a regulating blade and a removable film adhered to a surface of the regulating blade, according to some examples.

[0007] FIG. 5 is a top view of a regulating blade and a removable film adhered to a surface of the regulating blade, according to some examples. [0008] FIGS. 6A-6B are views of a regulating blade, a removable film adhered to a surface of the regulating blade, and a driven roller actuatable to remove the removable film, according to further examples.

[0009] FIG. 7 is a block diagram of a cartridge according to some examples.

[0010] FIG. 8 is a flow diagram of a process of forming a developer device according to some examples.

[0011] Throughout the drawings, identical reference numbers designate similar, but not necessarily identical, elements. The figures are not necessarily to scale, and the size of some parts may be exaggerated to more clearly illustrate the example shown. Moreover, the drawings provide examples and/or implementations consistent with the description; however, the description is not limited to the examples and/or implementations provided in the drawings.

Detailed Description

[0012] In the present disclosure, use of the term "a," "an," or "the" is intended to include the plural forms as well, unless the context clearly indicates otherwise. Also, the term "includes," "including," "comprises," "comprising," "have," or "having" when used in this disclosure specifies the presence of the stated elements, but do not preclude the presence or addition of other elements.

[0013] An image forming device such as an electrophotographic printing device can employ a photoreceptor on which an electrostatic latent image is formed, for use in transferring an image to a target medium (e.g., a print medium such as a paper substrate or a substrate of another material). The photoreceptor can be in the form of a photosensitive drum that includes a cylindrical tubular structure and a photosensitive layer on the cylindrical tubular structure.

[0014] A charging element can be used to charge a surface of the photosensitive drum to a uniform electrical potential (e.g., a negative electrical potential). In some examples, the charging element can include a charging roller. In other examples, a charging element can be in the form of a corona charger that can charge the surface of the photosensitive drum to a uniform electrical potential without making physical contact with the surface of the photosensitive drum.

[0015] A light source (e.g., a laser source, light emitting diode(s) (LEDs), etc.) can be activated by a controller of the image forming device to irradiate selected portions of the charged surface of the photosensitive drum, to form an electrostatic latent image on the photosensitive drum.

[0016] A developer device in the image forming device includes a developer (e.g., a developing roller) onto which a developing agent including an electrically charged toner is adhered. During operation of the image forming device, as the developing roller rotates relative to the photosensitive drum (which rotates in the same or opposite rotational direction of the developing roller), the toner in the developing agent on the developing roller is conveyed to the photosensitive layer of the photosensitive drum on which the electrostatic latent image has been formed, which develops the electrostatic latent image on the surface of the photosensitive drum to form a visible toner image on the photosensitive drum.

[0017] The developer device can also include a toner regulator, such as in the form of a regulating blade (also referred to as a "doctor blade"), that can regulate a thickness of a toner adhered to the outer surface of the developing roller. In other examples, the toner regulator can have a different form, such as a roller and so forth. A "nip" refers to a space between the toner regulator and the developing roller through which a layer of toner can pass.

[0018] During operation of the developer device, contamination can build up on the toner regulator, such as one a surface or multiple surfaces of the toner regulator. For example, if the toner regulator is in the form of a regulating blade, then contamination can build up on a first surface of the regulating blade facing the developing roller, as well as on a second surface (opposite the first surface) of the regulating blade facing away from the developing roller. [0019] The contamination can be caused by toner agglomeration in which toner material can build up and stick to the toner regulator, for example. The contamination on surfaces of the toner regulator can interfere with the nip between the toner regulator and the developing roller, and can cause various image quality issues in images formed on a print medium. Examples of such image quality issues include any or some combination of the following: streaking in the images formed on a print medium, blurring in the images formed on a print medium, and so forth.

[0020] In some examples, a developer device may be part of a removable cartridge that can be removably installed in an image forming device. If a user observes an image quality issue (such as that caused by contamination on the toner regulator), the user may replace the cartridge with a new cartridge. However, the replaced cartridge with the image quality issue may still have toner that can be used for image forming operations. If the replaced cartridge is discarded, then the toner remaining in the replaced cartridge is wasted, which can increase costs experienced by users that replace cartridges prematurely.

[0021 ] In accordance with some implementations of the present disclosure, cleaning mechanisms or techniques are provided to remove a contaminant built up on a toner regulator. In some examples, a cleaning mechanism includes a removable film adhered to a side (or alternatively, multiple sides) of the toner regulator.

[0022] A "film" can refer to a layer (or multiple layers) of material, which can be a pliable material to allow peeling of the film from the toner regulator. The film can conform to a shape of a surface of the toner regulator. Examples of materials that can be used to form removable films can include mylar, polycarbonate, polytetrafluoroethylene (PTFE), polyvinyl chloride (PVC), ultra high molecular weight polyethylene, polypropylene, polyethylene terephthalate (PET), and so forth.

[0023] In some examples, if the toner regulator includes a regulating blade that has a first surface facing a photoreceptor and a second surface that is on an opposite side of the regulating blade from the first surface, the cleaning mechanism can include a removable film adhered to the first surface or the second surface, or alternatively, the cleaning mechanism can include removable films adhered to both the first surface and the second surface of the regulating blade.

[0024] Removal of the first removable film and possibly the second removable film (in examples where the second removable film is implemented) can remove contaminants that have built up on the first surface and/or the second surface of the regulating blade. The first and/or second removable films can be used for other purposes in other examples, such as to refresh the regulating blade or another purpose.

[0025] FIG. 1 is a block diagram of an image forming device 100 that includes a developer device 102 that is to provide a developing agent including a toner to a photoreceptor, which can be in the form of a photoconductive drum 104 in some examples. The photoconductive drum 104 is rotatable during an operation of the image forming device 100 with respect to a rotational axis 105. In some examples, the photoconductive drum 104 is rotatable in a rotational direction 108. The photoconductive drum 104 may include a cylindrical metal pipe and a photoconductive layer formed on an outer surface of the cylindrical metal pipe.

[0026] A charging element, which can be in the form of a charging roller 110, can be used to charge a surface of the photoconductive drum 104 to have a uniform surface electric potential. The charging roller 110 is in contact with the photoconductive drum 104. The charging roller 110 is rotated (such as in a rotational direction 112) with respect to the photoconductive drum 104. A charging bias voltage is applied to the charging roller 110 to cause charging of the surface of the photoconductive drum 104. In other examples, instead of the charging roller 110, a corona charger can be used to charge the surface of the photoconductive drum 104.

[0027] The image forming device 100 includes an optical scanner 116 that is to form an electrostatic latent image on the surface of the photoconductive drum 104 by irradiating light corresponding to an image to be formed on the print medium 115 onto the surface of the photoconductive drum 104. The light can include a laser, for example. The irradiation of the surface of the photoconductive drum 104, which is charged, forms the electrostatic latent image on the photoconductive drum 104.

[0028] The developer device 102 includes a developer housing 120 that defines an inner space 122 in which a developing roller 124 is contained. The housing 120 includes an opening 125 through which the developing roller 124 faces the photoconductive drum 104. The developing roller 124 is rotatable about a rotational axis 126 in a rotational direction 127, for example. The developing roller 124 is in contact with the photoconductive drum 104.

[0029] The developing roller 124 when rotated attaches the developing agent in the inner space 122 of the developer device 102 to the surface of the developing roller 124. For example, the developing roller 124 may attach the developing agent to the outer surface of the developing roller 124 by a magnetic force.

[0030] In some examples, the developing roller 124 may include a developing sleeve and a magnet within the developing sleeve. The magnet is used to adhere the developing agent to the outer surface of the developing sleeve of the developing roller 124.

[0031 ] During operation of the image forming device 100, the toner of the developing agent on the developing roller 124 is transferred to the charged surface of the photoconductive drum 104, to develop a toner image on the photoconductive drum 104. The toner image developed on the photoconductive drum 104 corresponds to the electrostatic latent image formed on the photoconductive drum based on irradiated light from the optical scanner 116.

[0032] A cleaning blade 114 can be used to remove toner remaining on the surface of the photoconductive drum 104 after a transfer operation to transfer a toner image on the photoconductive drum 104 to a print medium 115. The removed toner can be provided to a waste toner container (not shown) of the image forming device 100. [0033] The cleaning blade 114 is located downstream (in the rotational direction 108 of the photoconductive drum 104) of the contact point between the developing roller 124 and the photoconductive drum 104. Note that the charging roller 110 is located upstream (in the rotational direction 108 of the photoconductive drum 104) of the contact point between the developing roller 124 and the photoconductive drum 104.

[0034] The image forming device 100 includes a transfer roller 118 that is rotatable with respect to the photoconductive drum 104 along a rotational direction 119, for example.

[0035] Although FIG. 1 shows various example rotational directions of rollers of the image forming device 100, in other examples, the rollers can have different rotational directions.

[0036] The transfer roller 118 faces the photoconductive drum 104 to form a transfer nip, and the print medium 115 is provided through the transfer nip. A transfer bias voltage can be applied to the transfer roller 118. The toner image developed on the surface of the photoconductive drum 104 is transferred to the print medium 115 by an electric field formed by the transfer bias voltage. The toner image transferred to the print medium 115 is attached to the print medium 115 by an electrostatic force.

[0037] The developer device 102 further includes a toner regulator to regulate the thickness of the developing agent on the outer surface of the developing roller 124. In some examples, the toner regulator is in the form of a regulating blade 128 (also referred to as a doctor blade). In other examples, the toner regulator can be in a different form, such as a regulating roller and so forth.

[0038] The regulating blade 128 is in contact with the developing roller 124. A regulating nip 130 (shown in a cross-sectional view of the regulating blade 128 and the developing roller 124 in FIG. 2) is provided between the regulating blade 128 and the developing roller 124. [0039] In accordance with some implementations of the present disclosure, a removable film is adhered to a surface of the regulating blade 128. For example, a contact surface of the removable film can have a layer of adhesive to allow the removable film to stick to the surface of the regulating blade 128. According to FIGS. 1 and 2, a removable film 140-1 is adhered to a first surface 128-1 of the regulating blade 128, and a removable film 140-2 is adhered to a second surface 128-2 of the regulating blade 128. The first surface 128-1 of the regulating blade 128 faces a first direction, e.g., generally toward the developing roller 124. The second surface 128-2 the regulating blade 128 faces an opposite second direction, e.g., generally away from the developing roller 124. Stated differently, the first surface 128-1 is on a first side of the regulating blade 128 that is opposite a second side of the regulating blade 128 on which the second surface 128-2 is provided.

[0040] In other examples, just one removable film (either 140-1 or 140-2) is adhered to one of the surfaces 128-1 and 128-2 the regulating blade 128.

[0041] The image forming device 100 also includes a developer supply 132 to supply the developing agent to the developer device 102. A supply roller 134 (or multiple supply rollers) when rotated can cause the developing agent to be transferred from the developer supply 132 to the inner space 122 of the developer device 102. In other examples, different mechanisms can be employed to transfer the developing agent from the developer supply 132 to the developer device 102.

[0042] In some examples, the developer device 102 may be removably mounted in the image forming device 100. For example, a depleted developer device 102 may be removed from the image forming device 100 and replaced with a new developer device.

[0043] In some examples, the developer device 102 can be part of a removably mounted print cartridge in the image forming device 100. A cartridge can include a volume containing a developing agent, and the developing agent in the volume can be transferred to the developing roller 124. Generally, a "cartridge" can refer to any container of a developing agent. The removably mounted print cartridge can include further components in addition to the developer device 102, such as the photoconductive drum 104 and so forth.

[0044] In further examples, multiple removable films can be provided on a surface of the regulating blade 128. For example, as shown in the cross-sectional view of the regulating blade 128 in FIG. 3, three removable films 140-2, 140-3, and 140-4 are provided on the surface 128-2 of the regulating blade 128. The removable film 140-2 is directly adhered to the surface 128-2 of the regulating blade 128, the removable film 140-3 is directly adhered to the removable film 140-2 (and indirectly adhered to the surface 128-2 through the removable film 140-2), and the removable film 140-4 is directly adhered to the removable film 140-3 (and indirectly adhered to the surface 128-2 through the removable films 140-3 and 140-2).

[0045] The removable films 140-2, 140-3, and 140-4 form a stack of removable films on the surface 128-2 of the regulating blade 128. In the stack, the removable film 140-4 is removed first, by peeling away from the remainder of the stack including the removable film 140-3 and the removable film 140-2. After removal of the removable film 140-4, the removable films 140-3 and 140-2 remain on the surface 128-2 of the regulating blade 128.

[0046] Next, after the removable film 140-4 has been removed, the removable film 140-3 can be peeled away from the removable film 140-2, which remains adhered to the surface 128-2 of the regulating blade 128. After removal of the removable film 140-3, the removable film 140-2 can be peeled away from the surface 128-2 of the regulating blade 128 at a later time.

[0047] The separate removals of the removable films 140-4, 140-3, and 140-2 can be performed as part of respective separate operations (e.g., cleaning operations to remove contaminants, or operations for other purposes) in the developer device 102. After some amount of use of the developer device 102, a first cleaning operation can be initiated, such as due to a user observing image quality issues on images printed on print media. In the first cleaning operation, the removable film 140-4 is removed to clean contaminants away from the regulating blade 128. As an example, the contaminant may be caused by agglomeration of toner material on surfaces of the regulating blade 128. After the first cleaning operation, the developer device 102 can be used again in image forming operations.

[0048] After further use of the developer device 102, a second cleaning operation can be initiated, in which the removable film 140-3 is removed to clean contaminants away from the regulating blade 128. After the second cleaning operation, the developer device 102 can be used again in image forming operations.

[0049] After additional use of the developer device 102, a third cleaning operation can be initiated, in which the removable film 140-2 is removed to clean contaminants away from the regulating blade 128. After the third cleaning operation, the developer device 102 can be used again in image forming operations.

[0050] Although examples depict three removable films provided on the surface 128-2 of the regulating blade 128, a different quantity (2 or more than 3) of removable films can be provided on the surface 128-2 of the regulating blade 128 in other examples.

[0051] In the example of FIG. 1 , one removable film 140-1 is adhered to the surface 128-1 of the regulating blade 128. In other examples, multiple removable films can be provided as a stack on the surface 128-1 of the regulating blade 128.

[0052] FIG. 4 is a perspective view of the regulating blade 128 with the removable film 140-2 adhered to the surface 128-2 of the regulating blade 128. The removable film 140-2 has a grip structure 402 (such as a pull tab or another type of structure) formed on a first end 406-1 of the removable film 140-2. In some examples, the grip structure 402 may be integrally formed with the removable film 140-2.

[0053] The grip structure 402 can be gripped by a user or by an automated force applicator (discussed further below) of the image forming device 100 to apply a tension on the removable film 140-2 generally along a direction of an arrow 404. [0054] In some examples, the tension can be applied on the grip structure 402 of the removable film 140-2 while the developer device 102 remains in the image forming device 100. In other examples, the tension can be applied on the grip structure 402 of the removable film 140-2 after removing the developer device 102 (such as in examples where the developer device 102 is part of a removable cartridge) from the image forming device 100.

[0055] In some examples, a loop structure 408 can be formed at a second end 406-2 of the removable film 140-2, where the second end 406-2 is opposite the first end 406-1 on the removable film 140-2.

[0056] FIG. 5 is a top view of the regulating blade 128 and the removable film 140-2 formed on the surface 128-2 of the regulating blade 128. The removable film 140-1 is omitted in the view of FIG. 5.

[0057] In the example of FIG. 5, a layer that makes up the removable film 140-2 has a first layer portion 410-1 that extends from the first end 406-1 to the second end 406-2 of the removable film 140-2, generally along a length axis 420 of the regulating blade 128. The regulating blade 128 has a length along the length axis 420.

[0058] At the second end 406-2, the layer folds over itself to form a second layer portion 410-2 of the removable film 140-2. The folding of the layer of the removable film 140-2 at the second end 406-2 forms the loop structure 408. The second layer portion 410-2 extends from the second end 406-2 to the first end 406-1 , also generally along the length axis 420.

[0059] The grip structure 402 (also referred to as a "primary" grip structure 402 in some examples) is integrally attached to the second layer portion 410-2. In some examples, a secondary grip structure 412 is integrally attached to the first layer portion 410-1 at the first end 406-1 of the removable film 140-2. In other examples, the secondary grip structure 412 can be omitted. For example, the secondary grip structure 412 can be used if multiple removable films in a stack are employed, but can be omitted if just one removable film is provided on a surface of the regulating blade 128.

[0060] To remove the removable film 140-2, a user or an automated force applicator grips the grip structure 402 and pulls on the grip structure 402 to apply a tension (along the direction of the arrow 404 shown in FIG. 4) to peel the removable film 140-2 away from the surface 128-2 of the regulating blade 128. The presence of the loop structure 408 allows the tension applied on the second layer portion 410-2 (as applied at the grip structure 402) to translate to a force having a force component F generally in a direction of an arrow 414. The force component F in the direction of the arrow 414 causes a peeling action of the first layer portion 410-1 away from the surface 128-2 of the regulating blade 128.

[0061] The primary grip structure 402 (and if present, the secondary grip structure 412) is (are) exposed to an outside of the developer device 102.

[0062] In some examples, the removable film 140-2 can pass through seals 502 and 504 (e.g., seals formed of an elastomer material or another type of material such as silicone (e.g., room-temperature-vulcanizing silicone), open celled foam polyurethane, etc.). The seals 502 and 504 can be engaged with a housing and/or other parts of the developer device 102, to keep the developing agent inside an inner space 122 of the developer device 102. When the removable film 140-2 is peeled away from the surface 128-2 of the regulating blade 128, the removable film 140-2 is pulled out of the developer device 102 through a gap between the seals 502 and 504. Once the removable film 140-2 is removed from the developer device 102, the seals 502 and 504, which are pliable, can expand to engage one another to form a seal to keep the developing agent inside an inner space 122 of the developer device 102.

[0063] In further examples, the seals 502 and 504 can be substituted with flaps that allow pulling of the removable film 140-2 through a gap between the flaps while keeping the developing agent inside the developer device 102. [0064] More generally, a retainer (which can be in the form of the seals 502, 504, or flappers, or any other retaining structure) allows the removable film 140-2 to pass through the retainer as the grip structure 402 is pulled to pull the removable film 140- 2 away from the regulating blade 128, while the retainer holds the developing agent inside the inner space 122 of the developer device 102.

[0065] FIG. 6A is a side view of the regulating blade 128 with the removable film 140-2 adhered to the surface 128-2 of the regulating blade 128. FIG. 6B is a top view of the arrangement of FIG. 6A.

[0066] As shown in FIGS. 6A and 6B, a driven roller 602 (which is an example of an automated force applicator) is attached to an end of the grip structure 402. The driven roller 602 is part of an image forming device, and can be driven by a motor or another type of actuator.

[0067] When the driven roller 602 is actuated to rotate, such as in a rotational direction 604, the driven roller 602 applies a tension on the grip structure 402. The applied tension peels the removable film 140-2 from the surface 128-2 of the regulating blade 128.

[0068] In other examples, other types of automated force applicators can be used to pull on the grip structure 402, such as a slider that can be actuated to move along an axis, and so forth.

[0069] If an automated force applicator such as the driven roller 602 is used, a controller in an image forming device can track an amount of toner of the developer device 102 that has been used, such as by counting the quantity of pages printed or measuring, using a sensor, an amount of toner remaining in the developer device 102. The controller can detect an amount of use condition of the developer device 102 (e.g., a page count has exceeded a threshold, the amount of toner used has exceeded a threshold, etc.) that indicates that toner contamination may have built up. In response to detecting the amount of use condition of the developer device 102 that indicates toner contamination buildup, the controller can activate the automated force applicator to remove a removable film from the regulating blade 128.

[0070] In other examples, the controller can detect image quality issues of images printed onto print media, such as by using an optical sensor. In response to detecting the image quality issues, the controller can activate the automated force applicator to remove a removable film from the regulating blade 128.

[0071] In examples where removal of the removable film is manually performed by a user, the controller can issue an alert to the user when contamination removal is desired, such as in response to any of the foregoing conditions.

[0072] FIG. 7 is a block diagram of a cartridge 700 for an image forming device, such as the image forming device 100 of FIG. 1 .

[0073] The cartridge 700 includes a photoreceptor 702. The photoreceptor 702 can be a photosensitive drum (e.g., 104 in FIG. 1 ). The cartridge 700 also includes a developing roller 704 to transfer a toner to an electrostatic latent image on the photoreceptor 702.

[0074] The cartridge 700 includes a regulator 706 that has a length along a length axis 708 of the regulator 706. In some examples, the regulator 706 can be in the form of a regulating blade.

[0075] The cartridge 700 includes a nip 710 between the regulator 706 and the developing roller 704, where a developing agent including the toner is to pass through the nip 710.

[0076] The cartridge 700 includes a removable film 712 adhered to a surface of the regulator 706, the removable film 712 extending along the length axis 708 of the regulator 706 and removable from the regulator 706 in response to an applied tension.

[0077] FIG. 8 is a flow diagram of a process 800 of forming a developer device for an image forming device, according to some examples. [0078] The process 800 includes arranging (at 802) a developing roller in the developer device. The process 800 includes arranging (at 804) a regulator in the developer device. The regulator to interact with the developing roller to define a layer of a developing agent on the developing roller.

[0079] The process 800 includes removably adhering (at 806) a removable film to a surface of the regulator, the removable film extending along a length axis of the regulator and removable from the regulator in response to an applied tension.

[0080] In the foregoing description, numerous details are set forth to provide an understanding of the subject disclosed herein. However, implementations may be practiced without some of these details. Other implementations may include modifications and variations from the details discussed above. It is intended that the appended claims cover such modifications and variations.