Patent ID: 12256048

DESCRIPTION OF THE EMBODIMENTS

Hereinafter, the present embodiment will be described with reference toFIGS.1to25. First, a schematic configuration of an image forming apparatus of the present embodiment will be described with reference toFIG.1.FIG.1is a cross-sectional view illustrating an image forming apparatus1of the present embodiment. In the present embodiment, the image forming apparatus1is a full-color copying machine that includes a plurality of photosensitive drums. However, the image forming apparatus1is not limited to this. For example, the image forming apparatus1may be a monochrome or monocolor copying machine or printer that includes a single photosensitive drum, or may be an ink-jet printer.

Image Forming Apparatus

Next, the image forming apparatus1will be described with reference toFIG.1. The image forming apparatus1has a configuration in which an image reading apparatus10is disposed above an image forming apparatus body2. The image forming apparatus1conveys a sheet P conveyed from a sheet cassette105, to an image forming portion106; and forms a toner image on the sheet P. Then the image forming apparatus1conveys the sheet P, on which the toner image has been formed in the image forming portion106, to a fixing apparatus107; and causes the fixing apparatus107to fix the toner image, still not fixed to the sheet P, to the sheet P by applying heat and pressure to the sheet P. That is, the image forming portion106forms an image that has been read by the image reading apparatus10, on the sheet. The sheet P may be a paper sheet such as a thin paper sheet or a thick paper sheet, a plastic film such as a sheet (OHP) used for overhead projectors, a paper sheet, such as a coated paper sheet, on which surface treatment has been performed, a specialized shape of sheet such as an envelope, or a cloth sheet.

The image forming portion106includes stations111,112,113, and114. The image forming apparatus1also includes an intermediate transfer belt115and a secondary transfer outer roller116. The stations111,112,113, and114respectively form toner images of yellow, magenta, cyan, and black on the intermediate transfer belt115. The configurations of the stations111,112,113, and114are the same as each other, except that the colors of toner are different from each other. The toner images formed by the stations111,112,113, and114are transferred onto the intermediate transfer belt115. The secondary transfer outer roller116transfers the toner image formed on the intermediate transfer belt115, onto the sheet P conveyed from the sheet cassette105. The fixing apparatus107fixes the toner image transferred onto the sheet P, to the sheet P by applying heat and pressure to sheet P. The sheet P to which the toner image has been fixed is discharged to a discharging tray119.

Image Reading Apparatus

FIG.2is a perspective view illustrating the image reading apparatus10. As illustrated inFIG.2, the image reading apparatus10includes a reader103and an auto document feeder (ADF)102, which are disposed above the image forming apparatus body2. The reader103reads the image of a document that is set by a user.FIG.3is a cross-sectional view illustrating the image reading apparatus10. As illustrated inFIG.3, the ADF102conveys a plurality of documents that is set on a document tray200, into the interior of the image reading apparatus10, so that a first reading unit306and a second reading unit307, which are disposed in the image reading apparatus10, can read the image of the document. Specifically, the document placed on the document tray200is conveyed along a conveyance path11by a conveyance portion14. The conveyance portion14includes a feeding roller300, a conveyance roller301, a conveyance roller302, a conveyance roller303, a conveyance roller304, a discharging roller305, and a guide member. The guide member forms the conveyance path11.

The image information of a first side of the document is read, via a first document-feeding-reading glass312, by the first reading unit306disposed in the reader103. The document is further conveyed by the conveyance roller304, and the image information of a second side of the document, opposite to the first side, is read, via a second document-feeding-reading glass313, by the second reading unit307disposed in the ADF102. The second reading unit307reads the image of a document in a position in which the second reading unit307is fixed with respect to the conveyance portion14relatively. After the image of the document is read, the document is discharged to a discharging tray201by the discharging roller305. In addition, the reader103includes a document platen glass104, and a document can be placed on the document platen glass104by opening and closing the ADF102. In this case, the reader103can read the image of the document by moving the first reading unit306in a sub-scanning direction and causing the first reading unit306to scan the document.

In the present embodiment, the ADF102includes an outer cover12that is one example of a first cover, a conveyance guide member507, a separation guide member500, the second reading unit307, and a reading-guide member403. The outer cover12can move between a first closed position in which the outer cover12is closed and a first open position in which the outer cover12is opened. In the first closed position, the outer cover12forms an upper conveyance path11aof the conveyance path11, formed between the outer cover12and both the conveyance guide member507and the second reading unit307. The upper conveyance path11ais one example of a first portion of the conveyance path11. In the first open position, the outer cover12opens the upper conveyance path11a. In the present embodiment, in the first closed position, the outer cover12forms the upper conveyance path11abetween the outer cover12and both the conveyance guide member507and the separation guide member500. The reading-guide member403is disposed opposite to the separation guide member500with respect to the second reading unit307, and forms a lower conveyance path11bbetween the reading-guide member403and the second reading unit307. The lower conveyance path11bis a portion of the conveyance path11, and is continuous with the upper conveyance path11a.

Second Reading Unit

FIG.4is a cross-sectional view of the second reading unit307. The second reading unit307is one example of a reading portion and a second reading portion. As illustrated inFIG.4, the second reading unit307includes a first casing member400and a second casing member401that are one example of a casing, a CIS311that is a contact image sensor, and the second document-feeding-reading glass313. The second reading unit307moves relative to the conveyance guide member507(seeFIGS.5to8) by pivoting and linearly moving with respect to the conveyance guide member507. Note that although the second reading unit307pivots and linearly moves with respect to the conveyance guide member507in the present embodiment, the present disclosure is not limited to this. For example, the second reading unit307may simply pivot with respect to the conveyance guide member507, may simply move linearly with respect to the conveyance guide member507, or may perform other relative movement with respect to the conveyance guide member507. The CIS311is one example of an image sensor (reading element) that reads the image of a document, and is housed by the first casing member400and the second casing member401. The CIS311is connected to a below-described FFC9, and reads the image of a sheet conveyed along the lower conveyance path11bof the conveyance path11.

A portion of the first casing member400on a side of the conveyance path is provided with an opening portion402for reading the image information of a sheet conveyed. The opening portion402is one example of an opening portion. That is, the first casing member400includes an edge portion402athat is one example of an opening-portion forming portion. The edge portion402aforms the opening portion402, through which the optical path of the CIS311extends toward the lower conveyance path11b. That is, the first casing member400includes the opening portion402through which light passes to the CIS311. The second document-feeding-reading glass313is stuck on the edge portion402aso as to cover the opening portion402. That is, the second document-feeding-reading glass313is one example of a transparent member, and covers the opening portion402when stuck on the first casing member400. The reading-guide member403that serves as a conveyance guide member is disposed on the outer side of the second document-feeding-reading glass313, that is, on the side of the conveyance path of the second document-feeding-reading glass313. The reading-guide member403is provided with a white sheet405and a protective glass404, disposed so as to face the CIS311. The protective glass404protects the white sheet405. The white sheet405is disposed for performing the shading compensation of the CIS311before the image information of a document is read. The protective glass404is disposed so that the surface of the white sheet405is not damaged (e.g., scratched) by a document conveyed.

Next, how the second reading unit307pivots in the ADF102of the present embodiment will be described with reference toFIGS.5to8.FIGS.5to8are front views illustrating a configuration for pivoting the second reading unit307of the present embodiment. As illustrated inFIG.5, in the interior of the ADF102, the separation guide member500, the conveyance guide member507, and the reading-guide member403constitute the conveyance guide. The separation guide member500is one example of a second cover, and constitutes a half side of the conveyance guide of the feeding and separation portion. That is, the separation guide member500is disposed closer to the upper conveyance path11athan the second reading unit307is. The separation guide member500can move between a second closed position (FIG.5) in which the separation guide member500is closed and a second open position (FIG.8) in which the separation guide member500is opened. In the second closed position, the separation guide member500covers the second reading unit307and an exposed portion90; in the second open position, the separation guide member500opens the second reading unit307and the exposed portion90. The second reading unit307is disposed so as to be able to pivot on a pivot shaft314. The second reading unit307can pivot between a reading position in which the second document-feeding-reading glass313faces the reading-guide member403and an exposed position in which the second document-feeding-reading glass313is exposed, when viewed from above, to the outside of the apparatus. The reading position is a position in which the second reading unit307reads the image of a document. Note that as illustrated inFIG.3, when the outer cover12is located in the first closed position, the outer cover12covers the upper portion of the separation guide member500. Thus, if the outer cover12is opened until the outer cover12is located in the first open position, it becomes possible to pivot the separation guide member500.

The conveyance guide member507guides a document in a position positioned downstream of the separation guide member500in the document conveyance direction. The conveyance guide member507constitutes a half side of the conveyance guide that is bent. The reading-guide member403constitutes a conveyance guide that the second reading unit307faces. The separation guide member500is provided with the pivot shaft502, and can be pivoted by a user for performing the jam handling and cleaning the second document-feeding-reading glass313disposed on the second reading unit307and the protective glass404disposed for the white sheet405. Note that in the present embodiment, members necessary for describing the configuration of the present invention are mainly described schematically.

Next, a state where the second reading unit307and the separation guide member500are located in closed positions, as illustrated inFIG.5, will be described. In this state, a pressing portion505formed in the separation guide member500pushes down a pressed portion506formed in the second reading unit307, downward from above. Thus, the second document-feeding-reading glass313of the second reading unit307abuts against the reading-guide member403that faces the second document-feeding-reading glass313, with a predetermined clearance being formed, so that the conveyance path is formed. Furthermore, a cam member501that serves as an interlocking member is disposed on the pivot shaft502of the separation guide member500. In addition, the separation guide member500is provided with a first contact portion503, and the cam member501is provided with a second contact portion504.

FIG.6is a front view illustrating a state where the separation guide member500has been pivoted in a D1direction. If the separation guide member500is pivoted by a predetermined angle or more, the cam member501also pivots in synchronization with the separation guide member500(seeFIGS.6to8). Furthermore, the separation guide member500is provided with a first projection portion510. Thus, if the separation guide member500is pivoted by a predetermined angle or more, the first projection portion510abuts against a below-described second projection portion1901, so that the pivoted state is kept.

On the other hand, the second reading unit307is provided with the pivot shaft314.FIG.7is a front view illustrating a state where the separation guide member500is pushing up the second reading unit307in a D2direction via the cam member501. As illustrated inFIG.7, if the separation guide member500is pivoted by a predetermined angle or more, a cam portion509of the cam member501, which pivots in synchronization with the separation guide member500, abuts against the second reading unit307. Thus, the second reading unit307starts to pivot on the pivot shaft314in the D2direction, in synchronization with the pivot motion of the separation guide member500.

FIG.8is a front view illustrating a state where the second reading unit307and the separation guide member500are located in open positions. As illustrated inFIG.8, if the second reading unit307is pivoted by a predetermined angle, the pressed portion506formed in the second reading unit307abuts against an angle regulation portion508formed in the conveyance guide member507, so that the second reading unit307is prevented from pivoting. In addition, the second reading unit307that is prevented from pivoting is caused to slide in a D3direction, by the cam member501. In the state illustrated inFIG.8, the pivoted state of the separation guide member500is finally kept by the second projection portion1901, which is a pivot regulation portion, and the pivoted state of the second reading unit307is also kept by the separation guide member500whose pivoted state is kept.

When documents are being conveyed, a user was not able to access the second document-feeding-reading glass313and the protective glass404of the white sheet405, as illustrated inFIG.5. In the present embodiment, however, as illustrated in HG8, a user can access both the second document-feeding-reading glass313and the protective glass404of the white sheet405by pivoting the second reading unit307and the separation guide member500. In particular, since the second reading unit307slides, as illustrated inFIG.8, in the D3direction in the latter half of the pivot motion, it becomes possible to secure a cleaning space801for cleaning the protective glass404of the white sheet405.

FFC

Next, a configuration of the FFC9, which is connected to the second reading unit307, will be described with reference toFIGS.9to13.FIG.9is a perspective view illustrating a positional relationship between the second reading unit307and the FFC9.FIGS.10to12are diagrams illustrating the position of the exposed portion90of the FFC9, and the arrangement of an FFC earth sheet3that serves as a conductive sheet member.

As illustrated inFIG.9, the FFC9, which is one example of a flexible cable, is connected to the CIS311disposed in the second reading unit307; and an FFC cover member901covers the connection portion of the FFC9so as to conceal the connection portion. As illustrated inFIG.10, since the second reading unit307is configured so as to be able to pivot in the ADF102, a portion of the FFC9, which serves as the exposed portion90, is exposed to the outside of the apparatus, when viewed from above, in a state where both the outer cover12and the separation guide member500are opened. That is, the exposed portion90of the FFC9bridges a space between the conveyance guide member507and the second reading unit307, and the FFC9transmits an electric signal (i.e., an image signal). The exposed portion90is one example of a bridging portion. The exposed portion90is located between the main-body unit102aand the second reading unit307, and exposes to an outside of the main-body unit102aand the second reading unit307. However, if the portion of the FFC9is exposed to the outside of the apparatus, the static electricity may fly from fingertips of a user to the exposed portion of the FFC9when the user performs work, and may cause the failure of an electric component. Note that the exposed portion90is a portion of the FFC9that is exposed to the outside in the clearance between the conveyance guide member507fixed to the main-body unit102aand the second reading unit307, in a state where the outer cover12is located in the first open position and the separation guide member500is located in the second open position.

In the present embodiment, as illustrated inFIG.11, the FFC earth sheet3that is a conductive sheet member is disposed so as to cover the exposed portion90from above. That is, the FFC earth sheet3covers a surface of the portion of the FFC9that is exposed to a user side. In addition, one end of the FFC earth sheet3is electrically grounded, via an earth wire1101. That is, the FFC earth sheet3is one example of a shield member that has conductivity, and that is grounded. The FFC earth sheet3is disposed closer to the upper conveyance path11athan the exposed portion90is. The FFC earth sheet3has conductivity and is grounded, so that the FFC earth sheet3discharges the static electricity, which is applied from the outside to the exposed portion90, to the ground. The width of the FFC earth sheet3is substantially equal to the width of the FFC9. However, the present disclosure is not limited to this. That is, the width of the FFC earth sheet3may be larger or smaller than the width of the FFC9.

FIG.12is a cross-sectional view of the ADF102viewed from the front side of the ADF102, and illustrates the arrangement of the FFC earth sheet3. In the present embodiment, since a user accesses the components from above, the FFC earth sheet3is disposed so as to cover the upper side of the exposed portion90of the FFC9.

Since the second reading unit307pivots as illustrated inFIGS.5to8, the exposed portion90of the FFC9and a portion of the FFC earth sheet3that corresponds to the exposed portion90will be both bent an expected number of times of pivot motion of the second reading unit307. Thus, it is necessary that the FFC earth sheet3be made of a material that can endure the expected number of bendings. In the present embodiment, the FFC earth sheet3is made of a metal-foil composite film. The metal-foil composite film is a composite material in which an aluminum foil is laminated on a PET base material made of polyester film. That is, the FFC earth sheet3is a film in which a metal layer and a polyester layer are laminated on each other.

Preferably, the FFC earth sheet3is disposed such that the aluminum-foil surface faces a direction from which the static electricity flies to the FFC9, and that the PET base material faces the FFC9. Specifically, in the present embodiment, the aluminum-foil surface is disposed above the FFC9inFIG.12. That is, in the present embodiment, the FFC earth sheet3is disposed such that the polyester layer is closer to the FFC9than the metal layer is. With this arrangement, the FFC earth sheet3shields the FFC9against the static electricity while making the durability against bending higher than that of an FFC earth sheet3that is a simple aluminum sheet.

FIG.13illustrates a state where the FFC cover member901, provided to the second reading unit307, is removed from the second reading unit307. With reference toFIG.13, how the FFC earth sheet3is disposed in the second reading unit307will be described.FIG.13is a diagram illustrating the arrangement of the FFC earth sheet3disposed in the second reading unit307. The second casing member401, which constitutes the second reading unit307, is provided with positioning projections1302. The positioning projections1302are positioned at positions that correspond to the positions of positioning hole portions1305of an FFC positioning sheet1304, and to the positions of positioning hole portions1303of the FFC earth sheet3. The FFC positioning sheet1304is stuck on the FFC9for positioning the FFC9. In the present embodiment, for preventing the FFC9and the FFC earth sheet3from becoming oblique in the pivot motion of the second reading unit307, two positioning projections1302are disposed, separated from each other in the width direction. For the same reason, two positioning hole portions1303are disposed, separated from each other in the width direction; and two positioning hole portions1305are disposed, separated from each other in the width direction.

The FFC9is fixed to the second reading unit307by inserting (fitting) the positioning hole portions1305of the FFC positioning sheet1304in the positioning projections1302. After the FFC9is fixed to the second reading unit307, the positioning hole portions1303of the FFC earth sheet3are fit, from above, to the positioning projections1302for covering the upper side of the FFC9with the FFC earth sheet3.

The FFC cover member901that serves as a fixing member is provided with an FFC fixing surface1300. The FFC9and the FFC earth sheet3are nipped and fixed by the FFC fixing surface1300of the FFC cover member901and the top surface of the second casing member401. In this configuration, the FFC9and the FFC earth sheet3are positioned and fixed in the second reading unit307.

Second Document-Feeding-Reading Glass

Next, a configuration for fixing the second document-feeding-reading glass313disposed in the second reading unit307will be described with reference toFIGS.14to17.FIGS.14to17are diagrams illustrating configurations of a glass earth sheet1400disposed on a portion of the second document-feeding-reading glass313of the present embodiment. As illustrated inFIGS.14and15, the second document-feeding-reading glass313is stuck on the first casing member400, which constitutes the second reading unit307, by using the glass earth sheet1400such that the glass earth sheet1400does not cover the opening portion402of the first casing member400. Thus, the glass earth sheet1400has a shape that does not cover the opening portion402. In this manner, the second document-feeding-reading glass313is stuck on the first casing member400via the glass earth sheet1400. The glass earth sheet1400is one example of a shield member. In addition, the glass earth sheet1400is stuck on the second document-feeding-reading glass313, while having conductivity and grounded. In the present embodiment, the glass earth sheet1400is disposed between the first casing member400and the second document-feeding-reading glass313. That is, the glass earth sheet1400is sandwiched between the first casing member400and the second document-feeding-reading glass313.

The glass earth sheet1400is a conductive sheet member having adhesiveness. The glass earth sheet1400may be a double-sided conductive tape, or may be a member in which an aluminum-foil tape and a double-sided tape are combined with each other. The aluminum-foil tape has an adhesive layer on one side. In the present embodiment, both sides of the glass earth sheet1400are adhesive, so that the second document-feeding-reading glass313is stuck on the first casing member400via the glass earth sheet1400. That is, the glass earth sheet1400fixes the second document-feeding-reading glass313on the first casing member400by pasting. In another case, as illustrated inFIG.15, the glass earth sheet1400may include a first sticking portion1500that serves as a double-sided tape, a conductive sheet member1501, and a second sticking portion1502that serves as a double-sided tape. In this case, the conductive sheet member1501may be stuck on the first sticking portion1500, and the second sticking portion1502may be stuck on the conductive sheet member1501. In another case, both sides of the conductive sheet member may be applied with adhesive, and the second document-feeding-reading glass313may be stuck on the first casing member400via the conductive sheet member1501. In another case, the conductive sheet member1501may be directly sandwiched between the second document-feeding-reading glass313and the first casing member400. In this case, the second document-feeding-reading glass313may be fixed to the first casing member400via a hook portion formed in the first casing member400, or via screws.

The glass earth sheet1400includes an electrical-connection portion1401that serves as an electrical contact, for electrically grounding the glass earth sheet1400, via the FFC cover member901, as described below. That is, in the configuration illustrated inFIG.15, the first sticking portion1500is disposed for bonding the first casing member400and the conductive sheet member1501. Thus, the first sticking portion1500and the conductive sheet member1501have an identical shape, and the electrical-connection portion1401of the conductive sheet member1501, as well as the other portion of the conductive sheet member1501can be stuck on the first casing member400. Unlike the first sticking portion1500, the second sticking portion1502does not have a shape that corresponds to the shape of the electrical-connection portion1401of the conductive sheet member1501. This is because the second sticking portion1502has only to be used for sticking the second document-feeding-reading glass313on the conductive sheet member1501.

In the present embodiment, the conductive sheet member1501is made of the above-described metal-foil composite film. That is, the metal-foil composite film that serves as the conductive sheet member1501is a composite material in which an aluminum foil is laminated on a PET base material made of polyester film. Thus, the conductive sheet member1501is a film in which the metal layer and the polyester layer are laminated on each other. The reason is that since the glass earth sheet1400has a shape1503that does not cover the opening portion402, the glass earth sheet1400is required to have a certain level of hardness for sticking the glass earth sheet1400on the first casing member400. If the glass earth sheet1400does not have the certain level of hardness, it will become difficult to stick the glass earth sheet1400on the first casing member400. However, if it is ensured by using a jig or the like that the glass earth sheet1400can be stuck on the first casing member400, a simple metal foil may be used instead of the metal-foil composite film.

Note that if the glass earth sheet1400is not disposed, a problem as described below may occur. That is, when a user performs work, such as the jam handling or the cleaning work for the second document-feeding-reading glass313, in the vicinity of the second document-feeding-reading glass313, static electricity may fly from fingertips of the user into the second reading unit307through a slight gap between the second document-feeding-reading glass313and the first casing member400. Similarly, static electricity may fly from a document that is being conveyed, into the second reading unit307through a slight gap between the second document-feeding-reading glass313and the first casing member400. If the static electricity enters the second reading unit307through the slight gap between the second document-feeding-reading glass313and the first casing member400, the static electricity may flow to an electric component, such as an LED element disposed in the CIS311; and may cause the failure of the electric component. Conventionally, the second document-feeding-reading glass313is stuck on the first casing member400via a simple double-sided tape that is not conductive. However, the double-sided tape is the same as an air layer, in terms of electricity. Thus, it is known that even if no gap seems to be formed, the static electricity passes through the double-sided tape, and may cause the failure of an electric component.

In the present embodiment, however, the whole circumference of the second document-feeding-reading glass313is stuck on the first casing member400via the conductive sheet member1501, as illustrated inFIG.15. Thus, the risk caused by the static electricity can be avoided. That is, the glass earth sheet1400is disposed on the edge portion402aor the first casing member400so as to surround the whole circumference of the opening portion402. In this configuration, the glass earth sheet1400discharges the static electricity applied from the lower conveyance path11bside to the second document-feeding-reading glass313.

Next, the relationship between the size of the glass earth sheet1400and the size of the opening portion402will be described. In the present embodiment, the glass earth sheet1400is formed such that the size and width of the glass earth sheet1400are equal to those of the edge portion402a. As a result, the sticking area of the double-sided tape can be increased, so that the force for sticking the second document-feeding-reading glass313to the first casing member400and keeping the second document-feeding-reading glass313on the first casing member400can be increased. In another case, the glass earth sheet1400may be formed like a thin line for discharging the static electricity. In this case, however, since the sticking area of the double-sided tape is decreased, it is necessary to dispose another member, in addition to the glass earth sheet1400, that keeps the second document-feeding-reading glass313on the first casing member400. The glass earth sheet1400may overlap with the opening portion402unless the glass earth sheet1400interferes with the reading operation of the CIS311.

Note that there is a case where it is not necessary to cover the whole circumference of the second document-feeding-reading glass313with the conductive sheet member1501because of the layout of electric elements. In this case, one portion of the glass earth sheet1400may be cut out, for example, as illustrated inFIG.16. That is, the glass earth sheet1400may be disposed on the edge portion402aor the first casing member400so as to extend along a portion of the opening portion402. Furthermore, if necessary for the ease of assembly or the like, the glass earth sheet1400may be constituted by a plurality of glass earth sheets, as illustrated inFIG.17, disposed on different portions of the edge portion402a. That is, the edge portion402aor the opening portion402includes a first portion402b, and a second portion402cdifferent from the first portion402b. The first portion402bis provided with a first glass earth sheet1700that is one example of a first shield member, and the second portion402cis provided with a second glass earth sheet1701that is one example of a second shield member. The first glass earth sheet1700and the second glass earth sheet1701have the same structure as that of the glass earth sheet1400, except that they have shapes different from the shape of the glass earth sheet1400.

If the glass earth sheet1400has a shape, as illustrated inFIGS.16and17, which does not extend along the whole circumference of the opening portion402, the glass earth sheet1400is required to have a configuration for compensating for the shape. That is, since the area of the double-sided adhesive tape decreases, it is desirable to fully check whether the second document-feeding-reading glass313will peel off, and use a double-sided tape in addition to the glass earth sheet, as appropriate. In addition, in a portion of the edge portion402aon which the glass earth sheet1400is not stuck, foreign matter may enter the second reading unit307through a gap between the second document-feeding-reading glass313and the edge portion402a. Thus, it is desirable that the gap be sealed with a double-sided tape.

Next, the relationship between the arrangement of LED elements of the CIS311and the shape of the glass earth sheet1400will be described with reference toFIGS.25A and25B. If the glass earth sheet1400is disposed separated from electric elements, such as LEDs of the CIS311, by a predetermined distance, the risk that the static electricity is applied to the electric elements can be reduced. For example, the predetermined distance is in a range from about 10 to 20 mm, or is about 15 mm. Thus, if an LED array315is used in the CIS311as illustrated inFIG.25A, it is desirable that the glass earth sheet1400be disposed so as to extend along the whole circumference of the opening portion402. As illustrated inFIG.25B, if LEDs316disposed in end portions of the CIS311are used in the CIS311, the glass earth sheet1400has only to be disposed in the vicinity of each of the LEDs316, separated from the LED316by a predetermined distance or less. In the present embodiment, the LEDs are disposed in end portions of the CIS311, as illustrated inFIG.25B, but the glass earth sheet1400is disposed so as to extend along the whole circumference of the opening portion402, as illustrated inFIG.25A. This arrangement of the glass earth sheet1400is used for reducing the deterioration of adhesive force that causes the second document-feeding-reading glass313to be stuck on the first casing member400, and for reducing the possibility that the foreign matter enters the second reading unit307through a gap of a portion of the edge portion402a, on which the glass earth sheet1400is not stuck.

Next, a configuration for grounding the electrical-connection portion1401of the glass earth sheet1400via the FFC cover member901will be described with reference toFIG.18.FIG.18is a diagram illustrating a configuration of the FFC cover member901that covers the FFC earth sheet3of the present embodiment. As illustrated inFIG.18, the FFC cover member901is provided with a surface1801that abuts against the first casing member400, and the surface1801also abuts against the electrical-connection portion1401of the glass earth sheet1400. On the abutment surface1801, a catching portion1800is formed for catching a hole portion formed in the first casing member400. The FFC cover member901includes the FFC fixing surface1300that fixes the FFC9and the FFC earth sheet3. The FFC9and the FFC earth sheet3are nipped by the FFC fixing surface1300and the top surface of the second casing member401, and thereby fixed.

The FFC cover member901is provided with snap-fit portions1301. The snap-fit portions1301and the catching portion1800can be detachably attached to the second reading unit307. In addition, four sponges1802that serve as elastic members are provided. Two of the sponges1802are disposed on the abutment surface1801of the FFC cover member901, and the other two of the sponges1802are disposed on the FFC fixing surface1300of the FFC cover member901. In addition, two conductive sheet members1803are provided. One of the conductive sheet members1803is disposed so as to connect the abutment surface1801and one of the sponges1802stuck on the FFC fixing surface1300, and the other of the conductive sheet members1803is disposed so as to connect the abutment surface1801and the other of the sponges1802stuck on the FFC fixing surface1300. The conductive sheet members1803are not required to have particular hardness and durability against bending. Thus, in the present embodiment, each of the conductive sheet members1803is an aluminum tape in which an adhesive layer is formed on an aluminum foil.

In this configuration, when the FFC cover member901is assembled to the second reading unit307, one end portion of each of the conductive sheet members1803is brought into pressure contact with the electrical-connection portion1401of the glass earth sheet1400by the elastic force of a corresponding sponge1802. In addition, the other end portion of each of the conductive sheet members1803is brought into pressure contact with the FFC earth sheet3. As a result, all of the glass earth sheet1400, the FFC earth sheet3, and the earth wire1101are electrically connected with each other, and are electrically grounded. This configuration can make the number of components smaller than that in a configuration in which the glass earth sheet1400and the FFC earth sheet3are separately grounded.

Self-Supporting Operation

Next, a self-supporting state of the separation guide member500and the second reading unit307will be described with reference toFIGS.19to24. The self-supporting state is produced when the separation guide member500is pivoted until the separation guide member500enters the open state illustrated inFIG.23or24. In the self-supporting state, the separation guide member500and the second reading unit307are regulated from pivoting.FIG.19is a diagram illustrating the second projection portion1901formed on the front side-plate1900of the present embodiment.FIG.20is a diagram illustrating a relationship between the separation guide member500and the cam member501of the present embodiment.FIG.21is a diagram illustrating a relationship between the separation guide member500and the front side-plate1900of the present embodiment.FIGS.22to24are diagrams each illustrating a relationship between the second projection portion1901and the first projection portion510of the present embodiment.

As illustrated inFIG.19, the front side-plate1900, which constitutes the frame in the ADF102, is provided with a fitting groove portion1003that corresponds to a front pivot shaft314disposed in the second reading unit307. The front pivot shaft314fits in the fitting groove portion1003. In addition, the front side-plate1900is provided with a fitting hole portion1002that corresponds to a front pivot shaft502disposed in the separation guide member500. The front pivot shaft502fits in the fitting hole portion1002. In addition, the front side-plate1900is provided with the second projection portion1901that is formed in the vicinity of the fitting hole portion1002, and that serves as a pivot regulation portion. The second projection portion1901abuts against the first projection portion510of the separation guide member500, so that the second projection portion1901keeps the pivoted posture of the separation guide member500and prevents the separation guide member500from returning to its original posture.

As illustrated inFIG.20, the cam member501is attached to the pivot shaft502of the separation guide member500on the front side-plate1900side. The cam member501is engaged with the pivot shaft502so as to be able to pivot around the pivot shaft502. If the separation guide member500pivots by a predetermined angle or more, the first contact portion503formed in the separation guide member500and the second contact portion504formed in the cam member501abut against each other. As a result, the separation guide member500and the cam member501pivot in synchronization with each other. In the vicinity of the pivot shaft502of the separation guide member500, the first projection portion510is formed.

As illustrated inFIGS.21to23, the front side-plate1900and the separation guide member500are assembled to each other such that the pivot shaft502of the separation guide member500fits in the fitting hole portion1002of the front side-plate1900. If the first projection portion510of the separation guide member500climbs over the second projection portion1901formed on the front side-plate1900, the separation guide member500is prevented from returning to its original posture even if a user releases a hand from the separation guide member500, so that the pivoted posture of the separation guide member500can be kept.

In addition, since the first contact portion503of the separation guide member500and the second contact portion504of the cam member501are in contact with each other, the pivoted posture of the cam member501is also kept. Furthermore, since the cam portion509of the cam member501supports the second reading unit307, the pivoted posture of the second reading unit307is also kept. Thus, a user can perform the cleaning work for the second document-feeding-reading glass313, which is disposed on the second reading unit307, and the protective glass404, which protects the white sheet405, and the jam handling in a state where the hand of the user is separated from the separation guide member500. Note that although the second projection portion1901is used, in the present embodiment, as the pivot regulation portion, the pivot regulation portion is not limited to this. For example, as illustrated inFIG.24, the pivot regulation portion that corresponds to the first projection portion510may be a recess portion2400, which corresponds to the first projection portion510. Note that on the back side of the ADF102, a back side-plate (not illustrated) is disposed, and in the back side-plate, a fitting groove portion and a fitting hole portion that are the same as those of the front side-plate1900are formed. The back side-plate supports the second reading unit307and the separation guide member500, like the front side-plate1900does.

As described above, in the image forming apparatus1of the present embodiment, the glass earth sheet1400is disposed between the second document-feeding-reading glass313and the edge portion402aof the first casing member400. Thus, the static electricity is grounded via the glass earth sheet1400, without entering the second reading unit307through a gap between the second document-feeding-reading glass313and the edge portion402a. As a result, the possibility that the static electricity causes the failure of the electric component that constitutes the image reading apparatus can be reduced.

In addition, in the image forming apparatus1of the present embodiment, since both sides of the glass earth sheet1400have adhesiveness, the second document-feeding-reading glass313can be fixed to the edge portion402awithout using another member. As a result, the increase in the number of components and assembly processes can be suppressed.

In addition, in the image forming apparatus1of the present embodiment, the glass earth sheet1400is a film that includes the metal layer and the polyester layer, which are laminated on each other. Thus, the glass earth sheet1400has appropriate stiffness. As a result, the sticking work of the glass earth sheet1400can be made easier.

Note that in the above-described embodiment, the description has been made for the case where the glass earth sheet1400is disposed between the second document-feeding-reading glass313and the edge portion402aof the first casing member400. However, the present disclosure is not limited to this. That is, the glass earth sheet1400may be stuck on another portion as long as the static electricity applied from the lower conveyance path11bside to the second document-feeding-reading glass313is discharged by the glass earth sheet1400. For example, the glass earth sheet1400may be stuck on a surface of second document-feeding-reading glass313on the lower conveyance path11bside, or may be stuck on an edge portion of the second document-feeding-reading glass313. In these cases, however, since the second document-feeding-reading glass313cannot be stuck on the edge portion402avia the glass earth sheet1400, the use of an additional member, such as a double-sided tape, is required.

In the above-described embodiment, the description has been made for the case where the second reading unit307is used as the reading portion. However, the present disclosure is not limited to this. For example, the reading portion may be a reading sensor of an adjusting apparatus of the image forming apparatus1. In this case, the adjusting apparatus causes the reading sensor to read the image of a sheet, on which the image has been fixed to the sheet, for performing image adjustment.

The present invention can suppress the static electricity from entering the reading portion through a gap between the transparent member and the casing of the reading portion.

Other Embodiments

While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention 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. 2022-147717, filed Sep. 16, 2022 which is hereby incorporated by reference herein in its entirety.