The present disclosure relates to an electrophotographic image forming apparatus.
In an electrophotographic image forming apparatus, such as a laser beam printer, a light-emitting diode (LED) printer, and a copying apparatus, a configuration in which a cartridge including a process member such as a developing roller is attachable to and detachable from an apparatus main body is widely adopted. In the configuration, it is necessary to supply power from the apparatus main body to the process member of the cartridge. A configuration in which the cartridge includes a cartridge electrical contact electrically connected to the process member, and the apparatus main body includes a main body electrical contact so as to come into contact with the cartridge electrical contact, is discussed (Japanese Patent Application Laid-Open No. 2010-190974).
In the main body electrical contact discussed in Japanese Patent Application Laid-Open No. 2010-190974, one end on the cartridge side is a spring, which is easily changed in position. Thus, in a case where power having different magnitudes are supplied from a plurality of main body electrical contacts to a plurality of cartridge electrical contacts, it is necessary to increase intervals of the plurality of main body electrical contacts so as not to come into contact with one another. This leads to an issue that the apparatus is easily upsized.
According to an aspect of the present disclosure, an image forming apparatus includes an apparatus main body including an electric substrate, and a first main body electrical contact and a second main body electrical contact which are electrically connected to the electric substrate, and a cartridge configured to be attachable to and detachable from the apparatus main body. The cartridge includes a first process member, a second process member, a first cartridge electrical contact electrically connected to the first process member, and a second cartridge electrical contact electrically connected to the second process member. The apparatus main body includes a common holding member holding a first end portion of the first main body electrical contact on a side of the cartridge and a second end portion of the second main body electrical contact on a side of the cartridge so as not to cause the first end portion and the second end portion to be electrically connected to each other. The holding member is configured to move between a contact position and a separation position, the contact position being a position at which the first end portion is contactable with the first cartridge electrical contact and the second end portion is contactable with the second cartridge electrical contact, the separation position being a position at which the first end portion is separated from the first cartridge electrical contact so as not to comes into contact with the first cartridge electrical contact and the second end portion is separated from the second cartridge electrical contact so as not to comes into contact with the second cartridge electrical contact.
Further features of the present disclosure will become apparent from the following description of exemplary embodiments with reference to the attached drawings.
Exemplary embodiments of the present disclosure will be described in detail below with reference to accompanying drawings. However, dimensions, materials, shapes, relative arrangement, etc. of components described in the exemplary embodiments are to be appropriately modified depending on a configuration of an apparatus to which the disclosure is applied and various conditions, and do not limit the scope of the present disclosure to the following exemplary embodiments.
(Image Forming Apparatus)
A first exemplary embodiment of the present disclosure will be described below.
An image forming apparatus 1 includes an apparatus main body 100A and four cartridges PY, PM, PC, and PK (hereinafter, referred to as cartridges P) attachable to and detachable from the apparatus main body 100A.
Each cartridge P includes a corresponding one of photosensitive drums 6Y, 6M, 6C, and 6K (hereinafter, referred to as photosensitive drums 6) and a corresponding one of developing rollers 8Y, 8M, 8C, and 8K (hereinafter, referred to as developing rollers 8). Each cartridge P includes a corresponding one of charging rollers 61Y, 61M, 61C, and 61K (hereinafter, referred to as charging rollers 61).
The apparatus main body 100A includes, as main components, a conveyance unit for feeding and conveying a recording material S, image forming units each forming an image on the recording material S, and a fixing unit for fixing the image on the recording material S.
The conveyance unit includes a feeding roller 2 and conveyance rollers 3. The recording material S stored in a feeding tray 1 is fed by the feeding roller 2, and is sent, via the conveyance rollers 3, to a transfer nip portion formed by an inner belt driving roller 4 and a secondary transfer roller 5 with an intermediate transfer belt 10 in between.
The image forming units include a laser scanner 70 and the intermediate transfer belt 10 in addition to the photosensitive drums 6 and the developing rollers 8 provided in the cartridges P. The photosensitive drums 6 rotate in a counterclockwise direction in
To form a color image, toner images of yellow, magenta, cyan, and black are each developed on the corresponding one of the photosensitive drums 6, and the formed toner images are sequentially transferred to the intermediate transfer belt 10 by the primary transfer units 9. Next, the toner images formed on the intermediate transfer belt 10 are collectively transferred to the recording material S sent to the transfer nip portion. Further, the recording material S on which the toner images have been transferred is sent to a fixing nip portion formed by a heating unit 12 and a pressurizing roller 13. The toner images are fixed onto the recording material S by being heated and pressurized by the fixing nip portion. The recording material S onto which the toner images have been fixed is conveyed and discharged by a discharge roller 14 and a discharge driven roller 15.
(Cartridge Tray)
The apparatus main body 100A includes the cartridge tray 35 on which the cartridges P are mountable.
The cartridge tray 35 is movable between a first position (image formation position) at which image formation is performable by using the cartridges P and a second position (attachment and detachment position) at which the cartridges P are attachable to and detachable from the cartridge tray 35. The apparatus main body 100A has an opening 200 through which the cartridges P pass when the cartridge tray 35 moves from the second position to the first position. The first position is inside the apparatus main body 100A.
As illustrated in
An electric substrate 30 for supplying necessary power to the cartridges P and the like is disposed on the left side surface of the apparatus main body 100A. Further, a control substrate 31 that processes image information transmitted from an external information apparatus such as a computer is disposed behind and above the electric substrate 30. The control substrate 31 is connected to the external information apparatus with an external connection cable connector, and the electric substrate 30 and the control substrate 31 are electrically coupled by bundled wires and a flexible flat cable (not illustrated).
Interlock switches 32 and 33 are respectively disposed on a front side and a rear side of the apparatus main body 100. The interlock switches 32 and 33 respectively detect opening and closing operation of the front cover 20 and a rear cover 21, and prevents operation of the apparatus main body 100A while the rear cover 21 is opened. The rear cover 21 is provided to enable, when a sheet conveyed by the conveyance rollers 3 and the secondary transfer roller 5 is jammed, removal of the jammed sheet. When the front cover 20 is opened, the cartridge tray 35 becomes movable between the first position and the second position. The cartridge tray 35 is slidable in a front-rear direction of the apparatus main body 100A, or in a direction orthogonal to a rotation axis direction of each of the photosensitive drums 6. A feeding motor 36 transmits driving force to the feeding roller 2 and the conveyance rollers 3.
(Cartridge Electrical Contact)
Each developing blade 7 includes a blade 7a and a supporting member 7b for supporting the blade 7a. In the present exemplary embodiment, the blade 7a is a thin plate (metal plate) made of stainless steel (SUS). The supporting member 7b is a plate that is made of iron and has an L-shaped cross-section orthogonal to a longitudinal direction. Thus, the developing blade 7 has conductivity.
Each developing unit D includes a developing electrical contact 810 (first cartridge electrical contact) electrically connected to the corresponding developing roller 8, and a blade electrical contact 710 (second cartridge electrical contact) electrically connected to the corresponding developing blade 7.
Here, a phrase “two members are electrically connected” may mean that the two members come into direct contact with each other, or one or a plurality of conductive members is provided between the two members and a conductive path is formed between the two members through the conductive members.
The developing electrical contact 810 includes a first contact portion 810a which comes into contact with a main body electrical contact of the apparatus main body 100A, a first bearing portion 810b for rotatably supporting the corresponding developing roller 8, and a first contact portion 810c (coupling portion) which is connected to the first contact portion 810a and the bearing portion 810b. The developing electrical contact 810 is made of a conductive resin.
The blade electrical contact 710 includes a second contact portion 710a (contact portion) configured to come into contact with a main body electrical contact as illustrated in
(Main Body Electrical Contact)
A configuration of the main body electrical contacts of the apparatus main body 100A according to the present exemplary embodiment will be described.
The coils 42 are electrically connected to the developing rollers 8 (first process members) of the developing units D, the developing blades 7 (second process members), and the charging rollers 61 (third process members). The coils 42 holds an interlock of the rear cover 21. Two coils 42 are disposed also on a rear cover holder 34, and supply power to the primary transfer units 9 and the secondary transfer roller 5.
The coils 42 includes coils 42a, 42b, 42c, 42d, 42e, and 42f (hereinafter, referred to as coils 42a to 42f). The coils 42a to 42f respectively include coil spring portions 42a1, 42b1, 42c1, 42d1, 42e1, and 42f1 (hereinafter, referred to as coil spring portions 42a1 to 42f1) each wound in a spiral shape at ends thereof on a side close to the electric substrate 30. The coils 42a to 42f further include linear portions 42a2, 42b2, 42c2, 42d2, 42e2, and 42f2 (hereinafter, referred to as linear portions 42a2 to 42f2) extending from the coil spring portions 42a1 to 42f1, respectively. The coil spring portions 42a1 to 42f1 are in electrical contact with respective contacts (not illustrated) of the electric substrate 30 while being compressed.
As illustrated in
In the image forming apparatus 1 according to the present exemplary embodiment, the power having different magnitudes are supplied to the developing rollers 8 and the developing blades 7 in order to prevent toner melt adhesion. More specifically, a developing roller bias applied to the respective developing rollers 8 is −500 V, and a developing blade bias applied to the respective developing blades 7 is −600 V. Thus, it is necessary for the conductive paths which supply the power to the developing rollers 8 and the conductive paths which supply the power to the developing blades 7 to be independent of each other.
In the present exemplary embodiment, the power is independently supplied to the developing units D of the colors and the developing unit D of black, in order to make the power supplied to the developing rollers 8 and the developing blades 7 of the colors in monochrome printing less than the power in color printing, or to make the power in monochrome printing zero. The color printing described herein indicates that an image is formed on the recording material S by using the image forming units of both of the colors and monochrome, and the monochrome printing indicates that an image is formed on the recording material S only by using the image forming unit of black.
Next, the main body electrical contacts which form, with the coils 42, the conductive paths for supplying power to the developing rollers 8 and the developing blades 7 will be described. In a case of the image forming unit of yellow among the image forming units of the four colors, the apparatus main body 100A includes a first main body electrical contact 81Y and a second main body electrical contact 71Y which serve as the main body electrical contacts as illustrated in
The linear portion 42a2 of the coil 42a is in contact with second main body electrical contacts 71Y, 71M, and 71C. The linear portion 42b2 of the coil 42B is in contact with first main body electrical contacts 81Y, 81M, and 81C.
As illustrated in
As illustrated in
As illustrated in
The first holding portion 43b (first press-fitted portion) and the second holding portion 43c (second press-fitted portion) of the holding member 43 illustrated in
The first coil spring portion 81b and the second coil spring portion 71b are easily changed in position. However, since the first bent portion 81a and the second bent portion 71a at the ends on the cartridge P side are held by the common holding member 43, a distance between the first bent portion 81a and the second bent portion 71a can be maintained with high accuracy. Thus, the distance between the first bent portion 81a (first main body electrical contact 81) and the second bent portion 71a (second main body electrical contact) can be reduced. This makes it possible to downsize the main body electrical contacts. Further, the areas of the first contact portion 810a of the developing electrical contact 810 and the second contact portion 710a of the blade electrical contact 710 of each cartridge P can be reduced, which makes it possible to downsize each developing unit D (each cartridge P).
As illustrated in
The first bent portion 81a of the first main body electrical contact 81 and the second bent portion 71a of the second main body electrical contact 71 are respectively in contact with the first contact portion 810a of the developing electrical contact 810 and the second contact portion 710a of the blade electrical contact 710. The electric substrate 30, the coil 42b, the first main body electrical contact 81, the developing electrical contact 810, and the developing roller 8 form the conductive path in this order, and the power is supplied to the developing roller 8. The electric substrate 30, the coil 42a, the second main body electrical contact 71, the blade electrical contact 710, and the developing blade 7 form the conductive path in this order, and the power is supplied to the developing blade 7.
(Moving Mechanism for Holding Member)
A moving mechanism for the holding member 43 will be described.
The slide member 45 is a member for swinging the holding member 43. Relationship between the slide member 45 and the holding member 43 will be described with reference to
When the slide member 45 is at the downstream-side position as illustrated in
When the slide member 45 moves from the downstream-side position to the upstream-side position in conjunction with movement of the front cover 20 from the closing position to the opening position, the holding member 43 moves by the inclined surface 45a of the slide member 45 and comes into contact with the restriction surface 45b as illustrated in
When the cartridge tray 35 mounted with the cartridge P is moved between the first position and the second position via the opening 200 with the front cover 20 at the open position, the holding member 43 is located at the separation position by the moving mechanism of the holding member 43 described above. Thus, in the state where the front cover 20 is located at the opening position, the first main body electrical contact 81 and the second main body electrical contact 71 do not respectively come into contact with the developing electrical contact 810 and the blade electrical contact 710 of the cartridge P. This makes it possible to smoothly move the cartridge tray 35 relative to the apparatus main body 100.
When the front cover 20 is moved from the opening position to the closing position, the holding member 43 is moved from the separation position to the contact position, and the first main body electrical contact 81 and the second main body electrical contact 71 respectively come into contact with the developing electrical contact 810 and the blade electrical contact 710 of each cartridge P. In such a manner, the image forming apparatus 1 is enabled to supply power to the developing roller 8 and the developing blade 7 of each cartridge P.
In the present exemplary embodiment, the ends of the main body electrical contacts are fixed to the holding member 43 by the holding portions of the holding member being press-fitting into the ends of the main body electrical contacts; however, the configuration is not limited thereto. Each of the main body electrical contacts and the corresponding holding portion may have a gap therebetween to the extent that the ends of the plurality of main body electrical contacts do not come into contact with one another.
In the present exemplary embodiment, the coil springs are used as the main body electrical contacts; however, the main body electrical contacts may be plate springs each formed of a thin metal plate.
In the present exemplary embodiment, the cartridges P are attached to and detached from the apparatus main body 100A by using the cartridge tray 35; however, the user may directly attach and detach the cartridges P to and from the apparatus main body 100A.
In the present exemplary embodiment, the process members to which power is supplied from the apparatus main body are the developing rollers and the developing blades; however, the process members are not limited thereto. In a case of using a cartridge provided with a toner supply roller which supplies toner to the corresponding developing roller, the toner supply roller is also the process member to which power is supplied from the apparatus main body.
In the present exemplary embodiment, the holding member is movable; however, the holding member may not be movable.
A second exemplary embodiment of the present disclosure will be described below. A configuration according to the present exemplary embodiment will be described.
In the first exemplary embodiment, the configuration in which the power having different magnitudes are suppliable to the developing unit D of black and the developing units D of yellow, magenta, and cyan has been described. In the present exemplary embodiment, a configuration in which power having the same magnitude is supplied to all of the developing units D of black, yellow, magenta, and cyan.
A coil 42g forms a part of the conductive path for supplying the same power to the developing rollers 8 of yellow, magenta, cyan, and black. A coil 42h forms a part of the conductive path for supplying the same power to the developing blades 7 of yellow, magenta, cyan, and black.
The coils 42g and 42h respectively include coil spring portions 42g1 and 42h1 each wound in a spiral shape at ends on the electric substrate 30 side. The coils 42g and 42h further include linear portions 42g2 and 42h2 extending from the coil spring portions 42g1 and 42h1, respectively. The coil spring portions 42g1 and 42h1 are in electrical contact with respective contacts (not illustrated) of the electric substrate 30 while being compressed.
The linear portion 42g2 of the coil 42g is in contact with the first main body electrical contacts 81Y, 81M, 81C, and 81K. The linear portion 42h2 of the coil 42h is in contact with the second main body electrical contacts 71Y, 71M, 71C, and 71K. The first main body electrical contact 81Y and the second main body electrical contact 71Y are held by the common holding member 43Y as in the first exemplary embodiment. Similarly, the first main body electrical contact 81M and the second main body electrical contact 71M are held by a common holding member 43M. The first main body electrical contact 81C and the second main body electrical contact 71C are held by a common holding member 43C. The first main body electrical contact 81K and the second main body electrical contact 71K are held by a common holding member 43K. The configurations of the first main body electrical contact 81 and the second main body electrical contact 71, and the holding method by the holding member 43 are the same as in the first exemplary embodiment.
Accordingly, as in the first exemplary embodiment, the distance between the first main body electrical contact 81 and the second bent portion 71a can be reduced. Thus, the present exemplary embodiment makes it possible to downsize the main body electrical contacts and the developing units D (cartridges P).
While the present disclosure has been described with reference to exemplary embodiments, it is to be understood that the disclosure is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions.
This application claims the benefit of Japanese Patent Application No. 2021-090732, filed May 31, 2021, which is hereby incorporated by reference herein in its entirety.
Number | Date | Country | Kind |
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2021-090732 | May 2021 | JP | national |
Number | Name | Date | Kind |
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20170075293 | Fukasawa | Mar 2017 | A1 |
20180246461 | Nakayashiki | Aug 2018 | A1 |
Number | Date | Country |
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2000122511 | Apr 2000 | JP |
2010190974 | Sep 2010 | JP |
2014038353 | Feb 2014 | JP |
2014112175 | Jun 2014 | JP |
2015148726 | Aug 2015 | JP |
Entry |
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Computer Translation of J:P2000-122511A to Sunahara Masaru. |
Number | Date | Country | |
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20220382205 A1 | Dec 2022 | US |