Image forming device and method of manufacturing the same

In an image forming device, at an end portion of a middle frame, a first protrusion and a second protrusion are arranged so as to protrude substantially parallel to each other. A plate-shaped arm extends from a leading end of the second protrusion in a direction towards a leading end of the first protrusion. A control protrusion is integrally arranged at a leading end of the plate-shaped arm. On the other hand, a rear side frame has a recessed portion. When the first protrusion, the second protrusion, and the plate-shaped arm are inserted into the recessed portion, the control protrusion passes a latching protrusion provided to the recessed portion, and the control protrusion and the latching protrusion are latched by facing each other.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a configuration and a manufacturing method of an image forming device such as a printer, a facsimile machine, and a copier, constructed to form an image including characters and graphics, etc. onto a paper as a recording medium.

2. Description of the Related Art

A conventional image forming device includes a photoconductive drum, a process unit that can be removably inserted into a device main body, a Light Emitting Diode (LED) head that exposes the photoconductive drum, an LED head supporting unit, and a rack gear.

The conventional image forming device further includes a supporting member, a pinion gear that engages with the rack gear, and an operation member having an operation portion for rotating the pinion gear. The supporting member can move in parallel between an adjacent position at which the LED head is positioned adjacent to the photoconductive drum and a distant position at which the LED head is positioned apart from the photoconductive drum.

In a configuration of the conventional image forming device, it has been considered to assemble a main body with frames formed of metal plates, and to attach an LED head supporting mechanism to the frames.

However, when assembling each of the frames, it requires considerable work to connect the large frames to each other. Moreover, the frames can tumble during an assembly operation, requiring time to manufacture, and efficiency has often been reduced. With this problem in mind, jigs etc. can be used for the assembly operation, however, it is hardly preferable since the cost of the jigs, securing of storage space for the jigs, and a moving operation of the jigs, etc. are additionally required.

SUMMARY OF THE INVENTION

In order to overcome the above-described problems, preferred embodiments of the present invention provide a solution to such problems. The features and aspects of the solution and its advantages will be described below.

According to a preferred embodiment of the present invention, an image forming device includes a metal plate first chassis, and a metal plate second chassis that is connected substantially vertically to the first chassis. A plate-shaped first protrusion, a plate-shaped second protrusion, a plate-shaped arm, a control protrusion, and a contact surface are arranged on an end portion of the first chassis. The first protrusion and the second protrusion protrude parallel or substantially parallel to each other. The plate-shaped arm is integrally arranged extending from the second protrusion in a direction at substantially 90 degrees with respect to a protruding direction of the second protrusion. The control protrusion is integral with the plate-shaped arm such that the control protrusion protrudes in a thickness direction of the plate-shaped arm. The contact surface is substantially vertical to the protruding direction of the first and the second protrusions, and can make contact with the second chassis. The second chassis has a recessed portion in which the first protrusion, the second protrusion, and the plate-shaped arm can be inserted. The recessed portion has a control surface and a latching protrusion. The control surface controls movement of the first protrusion and the second protrusion inserted in the recessed portion except for the movement in an inserting direction. The latching protrusion can make contact with the control protrusion of the plate-shaped arm inserted into the recessed portion.

With the above-described configuration, the first chassis and the second chassis can be vertically connected to each other easily without jigs. Accordingly, assembly of the chassis can be simplified, and an assembly operation can be improved.

In the above-described image forming device, it is preferable that the recessed portion has a circular or substantially circular protrusion with a control surface arranged at a leading end of the circular protrusion.

With the above-described configuration, since excessive friction is not generated when inserting the first protrusion and the second protrusion into the recessed portion, the assembly operation can be further improved.

In the above-described image forming device, it is preferable that the control protrusion protrudes such that a protruding amount thereof gradually increases from a front side in the inserting direction into the recessed portion.

With the above-described configuration, when inserting the first and the second protrusions into the recessed portion, simultaneously, the control protrusion is gradually pressed by the latching protrusion, and then elastically deforms the plate-shaped arm so that the control protrusion can easily pass the latching protrusion. Accordingly, the assembly operation can be improved more.

In the above-described image forming device, it is preferable that the first chassis and the second chassis are fixed preferably by a tapping screw used as a fixing member, for example.

With the above-described configuration, the first chassis and the second chassis can be reliably fixed by using the tapping screw. Further, since the tapping screw is preferably used, screw cutting at a hole in advance is not required, and it is convenient. Furthermore, when performing the screw cutting by the tapping screw, substantial force is applied onto the chassis, however, both of the chassis can prevent separation by the above-described connection structure. Thus, both of the chassis can be fixed by reliably performing the screw cutting.

According to a second preferred embodiment of the present invention, in a method for manufacturing the image forming device, temporary assembly is carried out by inserting the first protrusion, the second protrusion, and the plate-shaped arm of the first chassis into the recessed portion of the second chassis. Then, the first chassis and the second chassis are fixed by a fixing member.

With the above-described configurations, the first chassis and the second chassis can be vertically and temporarily assembled easily without jigs, and then can be fixed by the fixing member. Accordingly, the assembly of the chassis is simplified, and an assembly operation is improved.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

As illustrated in an external perspective view ofFIG. 1, a copy-and-facsimile MFP501as an image forming device includes an image scanning unit511, an operation panel512, a main body513, and a paper feed cassette514. The image scanning unit511functions as a flatbed scanner and an auto document feed scanner. The operation panel512is used for instructing a number of copies and a facsimile destination etc. The main body513has an image forming unit, etc. which forms an image onto a paper as a recording medium. The paper feed cassette514sequentially supplies the paper.

The copy-and-facsimile MFP501includes a front cover521arranged on a front side (a side on which the operation panel512is provided) of the main body513, and includes a jam access cover522arranged on one side surface of the main body513. The front cover521and the jam access cover522can be opened and closed. For example, when performing maintenance, etc., an inside of the main body513can be accessed by opening the front cover521and the jam access cover522.

FIG. 2illustrates an inside of the main body513of the copy-and-facsimile MFP501. As illustrated inFIG. 2, the paper feed cassette514for supplying a paper100is arranged at a lower portion of the main body513. The paper feed cassette514can be drawn out to a front side of the device (i.e. a front side of the paper ofFIG. 2). An image forming unit11is arranged above the paper feed cassette514. A fixing portion91and a paper discharge tray515are arranged further above.

In the inside of the main body513, a transportation path531is provided to transport the paper100from the paper feed cassette514to the paper discharge tray515. The transportation path531extends upward from one end side of the paper feed cassette514and reaches the image forming unit11. Then, after extending further upward and passing through the fixing portion91, the transportation path531curves in a horizontal direction and reaches onto the paper discharge tray515. Although not illustrated inFIG. 2, the image scanning unit511and the operation panel512are arranged above the paper discharge tray515.

The paper feed cassette514is opened on its upper side, and is provided with a flapper532on its bottom portion in a manner that the flapper532can turn upward and downward. A plurality of papers100are stacked on the flapper532. A paper feed roller21is arranged above the flapper532. When the flapper532is pushed up by a biasing spring (not illustrated) and the paper feed roller21is driven, an uppermost paper100is separated, picked up, and transported towards the transportation path531.

A separation roller22is arranged on an immediately downstream side of the paper feed roller21in the transportation path531. The separation roller22and a roller arranged opposite the separation roller22are driven, nip the paper100therebetween, and then separate the papers100one sheet at a time. A resist roller23is arranged on a downstream side of the separation roller22. The resist roller23and a roller arranged opposite the resist roller23are driven, nip the paper100therebetween, and then transport the paper100to the image forming unit11on a downstream side, adjusting oblique movement of the paper100.

As illustrated inFIGS. 2 and 3, which is an enlarged view of a relevant portion ofFIG. 2, the image forming unit11is provided with a photoconductive drum12, a charger13, an LED head14, a developing unit15, a transfer roller16, and a cleaner17. The charger13, the LED head14, the developing unit15, the transfer roller16, and the cleaner17are arranged around the photoconductive drum12.

A photoconductive layer formed of an organic photoreceptor is formed on a surface of the photoconductive drum12. The photoconductive drum12is rotationally driven by a driving motor (not illustrated). The charger13is what is called a scorotron charger, which uses a noncontact corona charging method. The surface of the photoconductive drum12is uniformly, and negatively, for example, charged by the charger13.

The LED head14as an exposing unit is arranged on a downstream side (i.e., a downstream side in a rotating direction of the photoconductive drum12. Hereinafter, like description will be applied to descriptions of the developing unit15, the transfer roller16, and the cleaner17) of the charger13, and is provided with a great number of light emitting diodes (LED) collaterally arranged in a paper width direction. A lens array in which a great number of gradient index lens are collaterally arranged is provided on a surface of the LED head14. The LED head14selectively emits light according to image data of a facsimile original document received via a telephone line and to image data scanned at the image scanning unit511. As a result, the surface of the photoconductive drum12is selectively exposed, and an electrostatic latent image is formed when charge energy on an exposed portion disappears.

The developing unit15is arranged on a downstream side of the LED head14. The developing unit15uses a binary developing system using toner and carrier as developer. Specifically, the developing unit15includes a synthetic resin-made developer container35, two screw-shaped agitating members31,32arranged inside the developer container35, a developer carrier33which is arranged adjacent to the photoconductive drum12with a slight space therebetween and is supported by the developer container35, and a control blade34arranged adjacent to a surface of the developer carrier33.

The agitating members31and32are rotationally driven, and circulate binary developer inside the developer container35while uniformly mixing the toner and the carrier by rotation. The developer carrier33preferably has a substantially cylindrical shape and is made of a nonmagnetic material. The developer carrier33rotationally fits around an outer side of a substantially cylindrically-shaped magnetic body36. The magnetic body36inside the developer carrier33magnetically absorbs the binary developer onto a surface of the developer carrier33. By rotating the developer carrier33under the above-described state, the binary developer is transported to a side of the photoconductive drum12while being maintained on the surface of the developer carrier33. A thickness of the binary developer on the surface of the developer carrier33is controlled by the control blade34to be even.

Then, at an adjacent portion where the photoconductive drum12and the developer carrier33come close to each other, the toner of the binary developer on the surface of the developer carrier33is selectively transferred onto the surface of the photoconductive drum12only to a portion exposed by the LED head14. As a result, a toner image according to the electrostatic latent image is formed onto the surface of the photoconductive drum12. The carrier of the binary developer and the remaining toner which has not been transferred to the side of the photoconductive drum12are collected into the developer container35.

The transfer roller16is arranged on a downstream side of the developing unit15and on an opposite side of the photoconductive drum12across the transportation path531. Prescribed voltage from a voltage source is impressed on the transfer roller16. Accordingly, the toner image formed on the surface of the photoconductive drum12is moved towards a side of the transfer roller16by rotation of the photoconductive drum12and transferred onto the paper100by electric field attraction force of the transfer roller16.

The cleaner17is arranged on a downstream side of the transfer roller16. The cleaner17removes electricity from the remaining toner which has not been transferred onto the paper100at the transfer roller16, scrapes the remaining toner off the surface of the photoconductive drum12, and accumulates the scraped toner.

In the above-described image forming unit11, at least the photoconductive drum12, the charger13, the developing unit15, and the cleaner17are preferably contained in a synthetic resin-made cartridge, and constitute a process cartridge5(a process unit). The paper100on which the toner image has been transferred at the image forming unit11is transported by the rotation of the photoconductive drum12to the fixing portion91arranged on a downstream side of the transportation path531.

As illustrated inFIGS. 2 and 3, the fixing portion91includes a heating source (such as a halogen lamp), a rotationally driven heat roller92, and a press roller93arranged opposite the heat roller92. The press roller93is pressed against the heat roller92by a biasing spring (not illustrated). In the above-described configuration, when the paper100passes between the heat roller92and the press roller93, the toner of the toner image is melted and fixed to the paper100by heat of the highly-heated heat roller92and pressure of the press roller93. The fixing portion91is provided with a separating claw94for preventing the paper100from sticking to and winding around the heat roller92.

As illustrated inFIG. 2, a transportation roller95is arranged on a downstream side of the fixing portion91, and a discharge roller96is arranged on a further downstream side. In the above-described configuration, the paper100transported from the fixing portion91is nipped between the transportation roller95and a driven roller arranged opposite the transportation roller95, and transported to a downstream side. Furthermore, the paper100is nipped between the discharge roller96and a driven roller arranged opposite the discharge roller96, and discharged onto the paper discharge tray515.

Next, a description will be made of frames which constitute the main body513with reference to a schematic perspective view ofFIG. 4. As illustrated inFIG. 4, the main body513includes a front side frame601, a rear side frame602, and a side frame603. The frames601,602, and603are vertically arranged. The rear side frame602is provided with a plurality of reinforcing frames630fixed thereto, and also provided with a driving unit (not illustrated) attached thereto for driving the image forming unit11, etc.

A middle frame605is horizontally arranged between the front side frame601and the rear side frame602. The middle frame605connects a middle portion in a height direction of the front side frame601and a middle portion in a height direction of the rear side frame602. Accordingly, the front side frame601, the rear side frame602, and the middle frame605jointly form a framework which is shaped like a capital “H”. As illustrated inFIG. 2, space for containing the paper feed cassette514is arranged on a lower side of the middle frame605, and space for containing the image forming unit11, the fixing portion91, and a power source unit18, which supplies power to each unit and portion of the device, etc. is arranged on an upper side of the middle frame605.

Now, with reference toFIG. 5, a description will be made of a configuration that facilitates assembly of the front side frame601, the rear side frame602, and the middle frame605. The frames601,602, and605are preferably made of metal plates.

As illustrated inFIG. 5A, at an end portion of the middle frame605horizontally arranged as a first chassis, a plate-shaped first protrusion571and a plate-shaped second protrusion572are integrally formed such that the first protrusion571and the second protrusion572protrude parallel or substantially parallel to each other in a horizontal direction. A horizontal plate-shaped arm573is integrally formed such that the plate-shaped arm573extends from a leading end of the second protrusion572in a direction at subtantially 90 degrees with respect to a protruding direction of the second protrusion572(i.e., in a direction extending towards a leading end of the first protrusion571).

Further, a control protrusion575is integrally formed at a leading end portion of the plate-shaped arm573such that the control protrusion575protrudes in a thickness direction of the plate-shaped arm573. The first protrusion571, the second protrusion572, the plate-shaped arm573, and the control protrusion575are punched out by press working when manufacturing the middle frame605.

Furthermore, an end portion of the middle frame605is bent with an appropriate width to form a vertical portion576. Moreover, one side of a base portion of the first protrusion571and the second protrusion572is tiered, and a small contact surface577is respectively arranged at each tiered portion. The contact surface577is substantially vertical to the protruding direction of the first protrusion571and the second protrusion572. The contact surface577can make contact with an adjacent portion of a recessed portion581to be described below. The recessed portion581is provided to the rear side frame (a second chassis)602.

On the other hand, the rear side frame602provided as the second chassis has the punched-out recessed portion581. The recessed portion581has an elongated substantially rectangular shape. The first protrusion571, the second protrusion572, and the plate-shaped arm573of the middle frame605can be inserted into the recessed portion581. The recessed portion581is punched out by press working when manufacturing the rear side frame602.

The recessed portion581is formed to surround all four sides of the first protrusion571and the second protrusion572, and is provided with control surfaces582for controlling movement of the inserted first protrusion571and second protrusion572except for the movement in an inserting direction. The recessed portion581is provided on its upper edge with circular protrusions583and584respectively positioned with respect to the protrusions571and572. The control surface582is respectively arranged on a lower end of the protrusions583and584. Furthermore, a latching protrusion585is arranged between the circular protrusions583and584on the upper edge of the recessed portion581.

The control protrusion575arranged on a side of the middle frame605protrudes such that a protruding amount thereof gradually increases from a front side in the inserting direction into the recessed portion581of the rear side frame602. A gradual slope is formed on an upper surface of the control protrusion575.

In the above-described configuration, the first protrusion571, the second protrusion572, and the plate-shaped arm573are inserted into the recessed portion581in a direction indicated by a heavy-line arrow ofFIG. 5A. Since the control surface582is respectively arranged preferably only at a leading end of the circular protrusions583and584at the upper edge of the recessed portion581, friction is not excessively generated upon insertion, and an inserting operation can be smoothly performed.

During the above-described inserting operation, the control protrusion575makes contact with the latching protrusion585. When inserted further, since the gradual slope of the control protrusion575is pressed downward by the latching protrusion585, the plate-shaped arm573is elastically deformed downward. Then, the control protrusion575passes through a lower side of the latching protrusion585. The contact surface577of the middle frame605makes contact with the rear side frame602, and almost simultaneously, the control protrusion575fully passes the latching protrusion585. The plate-shaped arm573is moved back to its original form by a restoring force, and the control protrusion575is latched by the latching protrusion585when facing the latching protrusion585in the inserting direction.

Thus, temporary assembly is carried out as illustrated inFIG. 5B, and the middle frame605can be vertically connected to be temporarily assembled without moving or coming off with respect to the rear side frame602. In addition, a similar connection structure illustrated inFIG. 5Ais provided between the middle frame605and the front side frame601, and by connecting to temporarily assemble similarly, the front side frame601, the rear side frame602, and the middle frame605can be temporarily assembled in the shape of capital “H”. As a result, the rear side frame602and the front side frame601can independently stand. Accordingly, since an assembly worker does not need to support the rear and front side frames602and601nor use jigs so that the frames602and601will not tumble, the assembly can be efficiently carried out.

After carrying out the temporary assembly, as illustrated inFIG. 5B, by screwing a tapping screw590as a fixing mechanism into a screw fixing hole591, the rear side frame602, the front side frame601, and the middle frame605are reliably fixed to each other. In addition, when screwing the tapping screw590, the middle frame605is pressed with substantial force via the tapping screw590for screw cutting of the screw fixing hole591, however, due to latching function between the latching protrusion585and the control protrusion575, the rear side frame602(or the front side frame601) does not come off the middle frame605nor tumble. Therefore, a fixing operation via the tapping screw590can be easily performed.

According to preferred embodiments of the present invention, the tapping screw590is preferably used, however, other screws can be used, and another fixing member can also be applied. In addition, the temporal assembly illustrated inFIGS. 5A and 5Bcan be applied not only to a case in which the frames are connected in the shape of capital “H”, but also to a case in which the frames are connected in the shape of capital “I” or “T”, for example. Moreover, shapes and other characteristics of the first protrusion571, the second protrusion572, the plate-shaped arm573, and the recessed portion581can be changed accordingly.

Now, with reference toFIG. 4again, a description will be made of a configuration of the frames. As illustrated inFIG. 4, a connecting frame604is horizontally arranged between the front side frame601and the rear side frame602, which are connected to each other via the middle frame605. The connecting frame604has an elongated shape, and connects the front side frame601and the rear side frame602by fixing one end of the connecting frame604in its longitudinal direction to the front side frame601, and by fixing the other end to the rear side frame602via a fixing mechanism such as screws (not illustrated).

A synthetic resin-made ventilation duct621is substantially horizontally arranged to connect the side frame603and the connecting frame604. The ventilation duct621is opened on its upper side, and has a lateral wall (a lower wall)622and vertical walls623arranged such that the vertical walls623vertically extend respectively from each end of the lateral wall622. A width of the lateral wall622gradually decreases from one end towards the other end of the ventilation duct621while a height of the vertical walls623gradually increases from one end towards the other end of the ventilation duct621.

As illustrated inFIG. 2etc., one end side of the ventilation duct621(i.e., a side on which the width of the lateral wall622is greater than the width thereof on the other side) is arranged adjacent to the photoconductive drum12, the charger13, and the fixing portion91, etc. Moreover, the lateral wall622has a penetrated circular hole624on the end side of the ventilation duct621. An exhaust fan (an exhaust mechanism)631and an ozone filter632are fixed on the other end side of the ventilation duct621. The lateral wall622has an inhaling hole637(shown inFIG. 2) on the other end side of the ventilation duct621, i.e. at a position adjacent to the power source unit18.

Accordingly, a substantially horizontal exhaust air stream635is provided inside the ventilation duct621so that the toner scattered from the photoconductive drum12, ozone generated by the charger13, and heated air generated by the fixing portion91can be discharged via the exhaust air stream635by driving the exhaust fan631. The air that has flowed through the exhaust air stream635eventually passes through a resin cover that covers the main body513or through an exhaust hole636provided to the paper discharge tray515, and then, is discharged outwards. Moreover, heated air around the power source unit18is also introduced from the inhaling hole637into the ventilation duct621and discharged by the exhaust fan631. Since the ozone generated by the charger13is absorbed by the ozone filer632, the ozone is not discharged to an outside of the main body513.

The paper discharge tray515is arranged directly above the ventilation duct621and covers the opened side of the ventilation duct621. Accordingly, an upper side of the exhaust air stream635is covered by the paper discharge tray515.

Next, a description will be made in detail of attachment of the ventilation duct621to the side frame603and the connecting frame604. As illustrated inFIG. 6, i.e., in an enlarged view of a relevant part ofFIG. 4, rib portions625and626are integrally formed at a portion corresponding in position to an end portion on a downstream side of the exhaust air stream635such that the rib portions625and626protrude laterally outward respectively from the vertical walls623respectively arranged at each side of the ventilation duct621. The rib portions625and626are positioned slightly higher than the lateral wall622. A round bar-shaped protrusion627respectively protrudes downward from a lower surface of the rib portions625and626. Moreover, the lateral wall622is provided with a penetrated inserting hole628. A shaft portion of a screw629provided as a fixing mechanism can be inserted into the inserting hole628.

On the other hand, the vertically arranged side frame603is bent at its upper end portion with a prescribed width, and is provided with a horizontal portion641. The horizontal portion641is provided with penetrated inserting holes642respectively positioned with respect to the protrusions627. The side frame603is also provided on its upper end portion with a concave portion643arranged between the inserting holes642so that an end portion of the ventilation duct621can fit to the concave portion643. The concave portion643is provided with a screw fixing hole644.

In the above-described configuration, the ventilation duct621can be fixed to the side frame603by inserting the screw629from above through the inserting hole628and by fixing the screw629to the screw fixing hole644under a state in which the protrusions627are respectively inserted from above into the inserting holes642.

The ventilation duct621is provided with an inserting hole651arranged at a middle portion of the ventilation duct621(i.e., a middle portion in a direction of the exhaust air stream635). The connecting frame604is provided with a screw fixing hole652arranged at a position with respect to the inserting hole651. Accordingly, the ventilation duct621can be fixed to the connecting frame604by inserting a screw653from above into the inserting hole651and fixing the screw653to the screw fixing hole652.

As described above, the side frame603and the connecting frame604can be connected via the ventilation duct621. Thus, since the synthetic resin-made ventilation duct621also functions as a reinforcing member which reinforces by connecting the side frame603and the connecting frame604, rigidity of a frame construction can be improved by the simple and lightweight configuration. In addition, since the ventilation duct621includes the integrally formed lateral wall622and the vertical walls623, although the ventilation duct621is preferably made of synthetic resin, the ventilation duct621can effectively improve rigidity of the frame construction. In particular, since the ventilation duct621is substantially horizontally arranged, the frame construction can endure external force in a horizontal direction.

In the ventilation duct621, an elongated harness guide portion661is arranged at an edge portion of the rib625so as to protrude to one of the vertical walls623. The harness guide portion661is provided with a guide wall662and an intermittent wall663which are arranged parallel or substantially to each other. The guide wall662and the intermittent wall663are integrally formed such that the walls662and663protrude upward from an end portion of the rib portion625. A harness containing space665is arranged between the guide wall662and the intermittent wall663. The intermittent wall663is provided with a plurality of interspaces arranged iteratively in its longitudinal direction. At each interspaced portion of the intermittent wall663, a fixing protrusion666is arranged protruding from an upper end portion of the guide wall662in a direction towards a side of the intermittent wall663.

In the above-described configuration, a harness633for supplying the exhaust fan631with power is set by being pressed into an inside of the harness containing space665. As a result, the harness633can be protected by being prevented from catching on other components, etc. Thus, according to the preferred embodiments of the present invention, since the ventilation duct621is also provided as a guide member for the harness633, the configuration can be more simplified and a number of components can be reduced.

Further, according to the preferred embodiments of the present invention, the inserting hole628and the protrusion627are arranged at an end portion on a downstream side of the exhaust air stream635of the ventilation duct621. On the other hand, the side frame603is provided with the inserting hole642. The ventilation duct621can be fixed to the side frame603by inserting the screw629into the inserting hole628and fixing the screw629to the side frame603under a state in which the protrusion627of the ventilation duct621is inserted into the inserting hole642. In the above-described configuration, the side frame603can be positioned by the protrusion627and the inserting hole642. Moreover, since a plurality of protrusions627(two protrusions627) are provided, the ventilation duct621and the side frame603can be fixed at many portions (at three portions in total), and bending of the side frame603can be controlled.

Since the paper discharge tray515is arranged to cover the upper side of the exhaust air stream635(refer toFIG. 2), the paper discharge tray515also guides the exhaust air stream635along with the ventilation duct621. Accordingly, the configuration can be more simplified.

Furthermore, more than three or only one protrusion(s)627and inserting hole(s)642can be provided. However, in order to prevent the side frame603from bending, it is preferable that a plurality of protrusions627and the inserting holes642are provided. Moreover, a connecting configuration using the protrusion627and the inserting hole642can be applied at a connecting portion of the ventilation duct621and the connecting frame604. A shape of the ventilation duct621, and a position and a shape of the harness guide portion661can be accordingly changed if required for its layout.

Next, a description will be made of the process cartridge5with reference toFIG. 7, etc. As illustrated in an external perspective view ofFIG. 7, the process cartridge5includes a synthetic resin-made housing201, which supports the photoconductive drum12therein in a manner that the photoconductive drum12can rotate. As illustrated inFIG. 3, the housing201is also provided as the developer container35in the developing unit15and as a retention container for the remaining toner in the cleaner17or the like.

As illustrated inFIG. 7, the housing201is provided with an elongated opening202. The LED head14arranged on a side of the main body513can be inserted into the opening202(refer toFIG. 3). A developing unit cover203is arranged on a lower side of the opening202. The developing unit cover203constitutes a part of the housing201, and as illustrated inFIG. 3, the developing unit cover203is arranged to cover an upper side of the developer container35of the developing unit15.

As illustrated inFIG. 7, the developing unit cover203horizontally extends towards an inner side of the opening202, and then bends near the photoconductive drum12. The developing unit cover203has a sloped surface204beyond a bent portion such that the sloped surface204gains altitude towards the photoconductive drum12.

In an inside of the opening202, upwardly protruding ribs205are respectively provided at each end of the sloped surface204(i.e., at each end in an axial direction of the photoconductive drum12). A longitudinal direction of the rib205is arranged substantially parallel to the sloped surface204. Moreover, positioning hole forming members206are respectively provided at each end side of the photoconductive drum12. The positioning hole forming member206has a positioning hole207. Positioning can be performed by inserting a positioning pin46(to be described below) into the positioning hole207. The positioning hole207of one of the positioning hole forming members206preferably has a round hole shape to which the positioning pin46can be fit with no space therebetween, and positions by a portion (a positioning portion) uniformly round shaped in its axial cross section. The positioning hole207of the other positioning hole forming member206has an elongated hole shape which facilitates the positioning by the positioning pin46.

The housing201of the process cartridge5has a small protruding portion208protruding in a horizontal direction at a center in the axial direction of the photoconductive drum12. In the developing unit15, a concentration sensor (not illustrated) for measuring toner concentration is provided near the protruding portion208. A first electrical connector211is arranged on one side of the protruding portion208, and can output a signal from the concentration sensor.

Next, a description will be made of a configuration for inserting the process cartridge5into the main body513with reference toFIG. 8. In a perspective view of a relevant portion, i.e. inFIG. 8, reference numeral221refers to a resin-made interior cover which is fixed to a front side of the front side frame601(FIG. 4). The interior cover221is exposed when the front cover521illustrated inFIG. 1is opened.

As illustrated inFIG. 8, the interior cover221has an insertion opening222into which the process cartridge5is inserted. An (overall) contour of the insertion opening222is substantially identical to a contour O2of the process cartridge5including the protruding portion208. Insertion space225for the process cartridge5is arranged inside the main body513beyond the interior cover221. A second electrical connector212which can be electrically connected to the first electrical connector211is provided inside the insertion space225.

An opening and closing door223is arranged on a side of the main body513so as to partially close the insertion opening222. The opening and closing door223is rotatably pivoted around a vertical shaft224. The opening and closing door223can be switched between a closed position illustrated inFIG. 8and an opened position where the opening and closing door223is turned from the closed position to an inside of the main body513(refer toFIG. 10). Moreover, the opening and closing door223is provided with a biasing spring (a first biasing member)231which biases the opening and closing door223towards the closed position.

Inside the main body513beyond the opening and closing door223, a control flapper (a control member)241is arranged on a lower side of the insertion space225. The control flapper241has a plate-shaped configuration and is rotatably pivoted around a horizontal shaft242on its one end. Thus, the control flapper241can be switched between a control position illustrated inFIG. 8and a releasing position where the control flapper241is turned downward from the control position (refer toFIG. 9). Although not illustrated, the control flapper241is provided with a biasing spring (a second biasing member) which biases the control flapper241towards the control position.

A first control claw (a first protrusion)251and a second control claw (a second protrusion)252are arranged on an upper surface of the control flapper241such that the first control claw251and the second control claw252protrude upward. The first control claw251and the second control claw252make contact with a lower portion of the opening and closing door223so that the first and second claws251and252can control turning of the opening and closing door223.

A control releasing cam253is arranged on the upper side of the control flapper241in a manner that the control releasing cam253protrudes upward. The control releasing cam253has a gradually sloped pushed surface. On the other hand, a pushing rib215is arranged protruding from a lower surface of the housing201of the process cartridge5. When the process cartridge5is inserted into the insertion opening222, the pushing rib215makes contact with the control releasing cam253. A longitudinal direction of the pushing rib215is arranged virtually along an inserting direction of the process cartridge5.

In the above-described configuration,FIG. 8illustrates a state in which the process cartridge5is to be inserted into the main body513. Under the state ofFIG. 8, the opening and closing door223is positioned at the closed position, and the control flapper241is positioned at the upper control position by the biasing spring (not illustrated). Accordingly, the first control claw251of the control flapper241is in contact with the lower portion of the opening and closing door223to control the turning of the opening and closing door223.

Under the state shown inFIG. 8, the process cartridge5is inserted into the insertion opening222in a direction parallel or substantially parallel to the axial direction of the photoconductive drum12. Since the insertion opening222is partially closed by the opening and closing door223under the state ofFIG. 8, the contour of the insertion opening222is substantially identical to a contour O1of a front portion of the process cartridge5in the inserting direction. Therefore, since a user can adjust the contour O1of the front portion of the process cartridge5to the contour of the insertion opening222, the process cartridge5can be easily inserted without any trouble in positioning the process cartridge5.

As illustrated inFIG. 9, when the process cartridge5is being inserted into the insertion space225, the pushing rib215makes contact with the control releasing cam253of the control flapper241. Accordingly, the control flapper241is pushed downward via the pushed surface of the control releasing cam253. Thus, since the control flapper241turns downward against the biasing spring (not illustrated) to be positioned at the releasing position, contact between the first control claw251and the opening and closing door223is eliminated. As a result, the opening and closing door223can be switched to the opened position. In addition, since the pushing rib215has an elongated shape, the control flapper241can be maintained under a control released state until the process cartridge5is inserted to a certain point from a state ofFIG. 9.

As illustrated inFIG. 10, when the process cartridge5is inserted into the insertion space225further, the protruding portion208of the process cartridge5makes contact with the opening and closing door223, and pushes towards a side of the insertion space225. As a result, the protruding portion208pushes and opens the opening and closing door223switching to the opened position, and can pass through the insertion opening222.

When the process cartridge5is inserted slightly further from a state ofFIG. 10, the pushing rib215passes a portion where the control releasing cam253is provided. As a result, the control flapper241is turned upward by the biasing spring (not illustrated) as indicated by an arrow, and returned to the control position. Accordingly, since the second control claw252makes contact with the lower portion of the opening and closing door223positioned at the opened position, the opening and closing door223is controlled at the opened position by the control flapper241and is fixed at the opened position after the protruding portion208passes through the insertion opening222.

When the process cartridge5is inserted further from the state ofFIG. 10, a state is established in which most portions of the process cartridge5are inside the insertion space225. Thus, insertion of the process cartridge5into the main body513is completed. At this time, since the first electrical connector211of the process cartridge5is electrically connected to the second electrical connector212on the side of the main body513, a signal indicating the toner concentration in the developing unit15of the process cartridge5is recognized at a control unit (not illustrated) provided in the copy-and-facsimile MFP501.

As described above, according to the preferred embodiments of the present invention, although the contour O2(the contour including the protruding portion208) at a middle portion of the process cartridge5is larger than the contour O1at an end portion of the process cartridge5, the process cartridge5can be easily inserted only by adjusting the contour O1at the end portion to the contour of the insertion opening222(the contour under a state in which the insertion opening222is partially closed by the opening and closing door223). Thus, a portion of the large contour O2can smoothly pass through the insertion opening222by pushing and opening the opening and closing door223. Accordingly, an inserting operation of the process cartridge5can be easily performed. In addition, since the opening and closing door223is controlled at the opened position under a state in which the process cartridge5is completely inserted, the opening and closing door223does not hinder when the protruding portion208passes through upon removing the process cartridge5.

When removing the process cartridge5from the main body513, an operation reverse to the above described operation can be carried out. That is, when the process cartridge5is being drawn out from the insertion opening222, while the protruding portion208passes through the insertion opening222, the pushing rib215pushes the pushed surface of the control releasing cam253downward. Thus, the control flapper241turns downward from the control position to the releasing position. As a result, since the control by the second control claw252of the control flapper241is released, the opening and closing door223can be switched to the closed position. Then, the protruding portion208passes through the insertion opening222completely, and simultaneously, the opening and closing door223is switched to the closed position by biasing force of the biasing spring231. When the process cartridge5is drawn out further, the pushing rib215passes the control releasing cam253. Thus, the control flapper241is turned upward to the control position by the biasing spring (not illustrated). As a result, since the first control claw251makes contact with the lower portion of the opening and closing door223positioned at the closed position, the opening and closing door223is controlled at the closed position by the control flapper241.

As described above, when removing the process cartridge5, the portion of the large contour O2including the protruding portion208passes through the insertion opening222, and simultaneously, the opening and closing door223is closed. Then, the opening and closing door223is controlled at the closed position. Accordingly, when inserting the process cartridge5again after its removal, the process cartridge5can be easily inserted just by adjusting the contour O1at the end portion to the contour of the insertion opening222(i.e., the contour of the insertion opening222when the insertion opening222is partially closed by the opening and closing door223).

The control flapper241is provided with the first control claw251and the second control claw252. The first control claw251makes contact with the opening and closing door223positioned at the closed position. The second control claw252makes contact with the opening and closing door223positioned at the opened position. Therefore, the opening and closing door223can be controlled at each of the positions with a simple configuration.

The control flapper241is also provided with the control releasing cam253arranged on its surface facing the process cartridge5(i.e., a surface facing the insertion space225, that is, an upper surface of the control flapper241). The control releasing cam253has the sloped pushed surface. Moreover, the pushing rib215for pushing the control flapper241via the control releasing cam253is arranged on a surface (the lower surface) of the process cartridge5that faces a side of the control flapper241. The longitudinal direction of the pushing rib215is arranged along the inserting direction of the process cartridge5. Therefore, by setting a length and a position of the pushing rib215accordingly, it is easy to set the right time to control or release the control of the opening and closing door223when inserting the process cartridge5.

According to the preferred embodiments of the present invention, while the protruding portion208of the process cartridge5is provided with the first electrical connector211, the second electrical connector212is arranged on the side of the main body513. When the process cartridge5is inserted into the main body513, the first electrical connector211is electrically connected to the second electrical connector212. Accordingly, when the toner concentration sensor is arranged near the protruding portion208, electrical wiring can be simplified. Moreover, the toner concentration can be reliably detected on the main body side when the process cartridge5is inserted into the main body513.

Alternatively, for example, the opening and closing door223and the control flapper241may be arranged such that the opening and closing door223and the control flapper241can move in parallel instead of being able to turn. Furthermore, a shape of the housing201and the protruding portion208, a shape and a position of the opening and closing door223, a shape of the insertion opening222, a shape and a position of the control flapper241, and a position and a shape of the control claws251and252, etc. can be accordingly modified.

Next, a detailed description will be made of a configuration for positioning the LED head14adjacent to or apart from the photoconductive drum12. That is, as described above, the photoconductive drum12, the charger13, the developing unit15, and the cleaner17preferably are integrally provided as the process cartridge5, and can be removed from the main body513and exchanged if required. However, as illustrated inFIG. 3, the photoconductive drum12and the LED head14are positioned adjacent to each other when forming an image. Accordingly, if the process cartridge5is inserted or removed under such a state (FIGS. 8 to 10), the LED head14may be damaged. In order to overcome such problem, the copy-and-facsimile MFP501according to the preferred embodiments of the present invention is provided with an LED head supporting mechanism41which can position the LED head14away from the photoconductive drum12if required.

FIGS. 11 and 12are external perspective views of the LED head supporting mechanism41viewed from different directions respectively.FIG. 13is a front view of the LED head supporting mechanism41under a state in which a slide member is positioned at an adjacent position. As illustrated inFIGS. 11 and 12, the LED head supporting mechanism41is provided with LED supporting frames42and43arranged parallel to each other. As illustrated inFIG. 12, etc., a guide rail44is respectively provided on a mutually facing surface of the LED supporting frames42and43.

A slide member51is arranged between the LED supporting frames42and43. The LED head14is attached to the slide member51. The slide member51is provided with a base side member52and a leading end side member (a head holder)53, which are made of synthetic resin (in the present preferred embodiment, made of acrylonitrile butadiene styrene resin). The base side member52has a slightly elongated substantially rectangular shape. Both end portions of the base side member52in its longitudinal direction are respectively supported with respect to the LED supporting frames42and43via the guide rail44. Thus, the base side member52can slide along the guide rail44in a horizontal direction (a first direction D1).

The leading end side member53is connected to an end portion of the base side member52on a side closer to the photoconductive drum12. The LED head14is attached to a leading end portion of the leading end side member53. As illustrated inFIG. 13, a leading end side of the LED head14is slightly lifted obliquely upward from the horizontal direction. Therefore, a light irradiating direction with respect to the photoconductive drum12faces obliquely upward. As illustrated inFIG. 11, a lens array45in which a great number of gradient index lens are aligned is arranged on a surface of the LED head14. In the LED head14, an uneven portion (a corner portion)49is respectively arranged near each end in a longitudinal direction of the lens array45.

The positioning pin (a positioning body)46is respectively fixed to the LED head14at each end thereof in the longitudinal direction. The positioning pin46faces substantially parallel to a direction of the LED head14(i.e., substantially parallel to the light irradiating direction). The positioning pin46can accurately position the LED head14with respect to the photoconductive drum12by being fit into the positioning hole207provided on the positioning hole forming member (a counterpart member)206of the process cartridge5. The positioning pin46has a round-bar shape with a semispherical portion on its leading end, and positions by its cylindrical portion (a positioning portion), which has an even round shape in its axial cross section.

As illustrated inFIG. 13, a guide plane47is arranged on a leading end portion of the base side member52. The guide plane47is arranged in a direction vertical relative to the light irradiating direction of the LED head14(i.e. in a direction vertical to the positioning pin46). On the other hand, the leading end side member53is provided with a plurality of polyacetal resin cylindrical co-rotating rollers (rolling body)48such that the cylindrical co-rotating rollers48are rotatably supported and can roll on the guide plane47. Accordingly, the leading end side member53can move with respect to the base side member52in a direction along the guide plane47, i.e. in a direction (a second direction D2) slightly oblique to the vertical direction.

As illustrated inFIGS. 11 and 12, a metallic operation transmission shaft55is arranged between the LED supporting frames42and43such that the operation transmission shaft55is rotatably supported. One end of the operation transmission shaft55penetrates and extends through the LED supporting frame42. An operation lever (an operation member)56is fixed to a leading end of the operation transmission shaft55. On the other hand, the other end of the operation transmission shaft55penetrates and extends through the LED supporting frame43. A biasing spring (not illustrated) is attached to the other leading end of the operation transmission shaft55.

Pinion gears57are respectively fixed to each end portion of the operation transmission shaft55. The pinion gears57are respectively provided with a plurality of teeth58aligned in an arc. The pinion gears57preferably are composed of identical components. The operation transmission shaft55has a shape of capital “D” in its cross section. The pinion gears57arranged similarly in phase and fixed to the operation transmission shaft55.

A rack59is respectively arranged on a surface (an upper surface) of the base end member52of the slide member51in a manner that each of the racks59respectively engages with the pinion gears57. The racks59are preferably provided as a pair, and respectively have teeth similarly positioned with respect to each other. A tooth top surface of rack59is flush with the surface of the base side member52(i.e., there is no difference in level between the tooth top surface and the surface of the base side member52). Meanwhile, a base surface of the tooth is concave from the surface of the base side member52. In addition, the leading end side member53of the slide member51is provided with a linear concave groove60such that the concave groove60extends from an end portion of the rack59.

FIGS. 11 through 13illustrate a state in which the LED head14is positioned adjacent to the photoconductive drum12. A position of the slide member51in the above-described state will be hereinafter referred to as an adjacent position. When a user performs a rotating operation of the operation lever56from the above-described state, such operational force is transmitted to the pinion gear57via the operation transmission shaft55. Accordingly, accompanying rotation of the pinion gear57, the slide member51withdraws along the first direction D1from the photoconductive drum12. As a result, as illustrated inFIG. 14, the LED head14can be positioned apart from the photoconductive drum12. A position of the slide member51under the above-described state will be hereinafter referred to as a distant position. Thus, by operating the operation lever56, the slide member51, and consequently, the LED head14can also be switched between the adjacent position and the distant position.

As illustrated inFIGS. 11 and 12, a metallic supporting plate70is fixed between the LED supporting frames42and43to connect each upper end thereof. A circuit board78is arranged on an upper surface of the supporting plate70to control the LED head14. A cover79is arranged to cover and guard the circuit board78. As illustrated inFIG. 13, the circuit board78is positioned opposite the slide member51across the operation transmission shaft55.

A flexible flat cable80is drawn from the circuit board78. The flexible flat cable80electrically connects between the circuit board78and the LED head14.

A cable guiding member71is fixed to the supporting plate70and arranged between the circuit board78and the slide member51. The cable guiding member71is provided with two guide portions72for guiding the flexible flat cable80. Each of the guide portions72is respectively positioned adjacent to the operation transmission shaft55. The cable guiding member71is preferably made of insulating synthetic resin, and as illustrated inFIG. 11, the cable guiding member71is integrally formed to connect between the guide portions72.

As illustrated inFIG. 13, each of the guide portions72respectively preferably has a stepped form, and respectively guides the flexible flat cable80along each stepped path. An end portion (a lower end portion) of the guide portion72on a side of the slide member51is positioned closer to the slide member51than the operation transmission shaft55.

As illustrated inFIG. 11, the base side member52of the slide member51is provided with a cable containing groove75for containing the flexible flat cable80. The cable containing groove75is concavely arranged on the upper surface of the base side member52such that the cable containing groove75is opened on a side close to the cable guiding member71. As illustrated inFIG. 13, a sloped guide surface (a guide surface)76is arranged on one side of the cable containing groove75. The flexible flat cable80is guided by the sloped guide surface76such that the flexible flat cable80is drawn out from the upper surface of the slide member51in an obliquely upward direction (a third direction D3) apart from the photoconductive drum12towards the circuit board78.

As illustrated inFIG. 11, a lid cover77is provided to close the opened side of the cable containing groove75. A surface of the lid cover77is flushed with the surface of the base side member52.

As described above, the flexible flat cable80can be guided by the guide portion72of the cable guiding member71so that the flexible flat cable80does not make contact with the metallic supporting plate70and the operation transmission shaft55. Accordingly, noise can be prevented from intruding into a control signal that moves down a signal line provided in the flexible flat cable80, and erroneous operations of the LED head14can be avoided. Moreover, the flexible flat cable80can avoid being damaged by scraping against the operation transmission shaft55.

Further, the end portion of the cable guiding member71on the side of the slide member51is positioned closer to the slide member51than the operation transmission shaft55. Therefore, the flexible flat cable80can be reliably prevented from making contact with the metallic supporting plate70and the operation transmission shaft55.

Furthermore, the cable guiding member71has the stepped configuration so that the cable guiding member71does not interfere with the operation transmission shaft55. The cable guiding member71is positioned adjacent to the operation transmission shaft55. Therefore, space adjacent to the operation transmission shaft55can be effectively utilized as space for placing the flexible flat cable80. Moreover, the LED head supporting mechanism41can be downsized.

In addition, the end portion of the cable guiding member71on the side of the slide member51is positioned apart from the photoconductive drum12farther than the operation transmission shaft55. Therefore, even if the flexible flat cable80is loosened due to movement of the slide member51, the flexible flat cable80can be reliably prevented from making contact with the operation transmission shaft55.

As for a relation with a cleaning mechanism64of the LED head14to be described below, the end portion of the cable guiding member71on the side of the slide member51is positioned on a side closer to the slide member51than to the cleaning mechanism64, and positioned on a side farther from the photoconductive drum12than the cleaning mechanism64. Therefore, the flexible flat cable80can be prevented from making contact with the cleaning mechanism64, and consequently, signal noise or damage of the flexible flat cable80caused by such contact can be prevented.

Further, the slide member51is provided with the sloped guide surface76. The guide surface guides the flexible flat cable80so that the flexible flat cable80can be drawn out from the slide member51in the direction (in the third direction D3) from the photoconductive drum12towards the circuit board78. As illustrated inFIG. 14, a position at which the flexible flat cable80is drawn out from the slide member51when the slide member51is positioned at the distant position is farther than the guide portion72of the cable guiding member71from the photoconductive drum12. Accordingly, even when the slide member51is switched to the distant position, the flexible flat cable80is loosened at a position apart from the operation transmission shaft55as illustrated inFIG. 14. Therefore, the flexible flat cable80can be reliably prevented from making contact with the operation transmission shaft55.

Next, a description will be made of the cleaning mechanism64for cleaning a light irradiating surface (a front surface of the lens array45) of the LED head14. That is, when forming an image, as illustrated inFIG. 3, etc., since the LED head14is positioned adjacent to the photoconductive drum12, the remaining toner and paper scraps, etc. scattered from the photoconductive drum12are adhered to and contaminate the LED head14, negatively affecting exposure. According to the preferred embodiments of the present invention, in order to overcome the above-described problem, the LED head supporting mechanism41is provided with the cleaning mechanism64for cleaning the LED head14.

A description will be made of a configuration of the cleaning mechanism64. As illustrated inFIG. 11, a cleaning guide rail (a guide member)66is bridged between the LED supporting frames42and43. The cleaning guide rail66is arranged above the slide member51and in parallel with a longitudinal direction of the LED head14.

A sliding body67is slidably attached along the cleaning guide rail66. One end of a rod68is connected to the sliding body67, and the other end of the rod68penetrates and extends through the LED supporting frame42. A cleaning operation lever (a cleaning operation member)69is fixed to the penetrating and extending end of the rod68. Accordingly, by operating to press or draw out the cleaning operation lever69, the sliding body67can slide in a direction parallel to the longitudinal direction of the LED head14.

As illustrated inFIG. 15(an enlarged view of a relevant part ofFIG. 15), a turning arm (a cleaning arm)81is axially supported on the sliding body67. The turning arm81can turn around an axis line arranged along a longitudinal direction of the guide rail66, and can move in parallel along the axis line along with the sliding body67.

An attaching member82is attached to the turning arm81, and includes a brush (a cleaning body)85. A contacting arm83is arranged at a middle portion of the turning arm81. A leading end surface (a sliding surface)89of the contacting arm83makes contact with the upper surface of the base side member52of the slide member51and can slide. A width w1of the sliding surface89is preferably wider than a width w2of the rack59arranged on the base side member52.

Further, a biasing spring (a biasing member)84is positioned between the sliding body67and the turning arm81. The biasing spring84biases the turning arm81in a clockwise direction inFIG. 14.

The attaching member82includes the brush (the cleaning body)85, which is preferably made of acrylic moquette, for example. The brush85can clean the front surface of the lens array45of the LED head14. As illustrated inFIG. 15, two attaching pins97and97are protrudingly arranged at a leading end of the turning arm81. The attaching member82includes attaching holes98arranged such that each of the attaching holes98is arranged concavely to respectively fit to the attaching pins97. The attaching member82further includes a snap fit portion (a latching portion)86, which can be latched at a groove87provided to the turning arm81. In the above-described configuration, the snap fit portion86is latched at the groove87by inserting the attaching pin97of the turning arm81into the attaching hole98of the attaching member82. Thus, the attaching member82can be attached to the turning arm81.

With the above-described configuration, at the adjacent position illustrated inFIGS. 11 through 13and15, the base side member52of the slide member51lifts up the turning arm81via the contacting arm83. In other words, since the sliding surface89of the contacting arm83makes contact with the slide member51against biasing force of the biasing spring84, the brush85does not make contact with the slide member51. Thus, since the brush85does not make contact with any other components when the slide member51is positioned at the adjacent position, the brush85does not wear out, and its cleaning effect on the LED head14does not decrease.

On the other hand, at the distant position as illustrated inFIG. 14, since the slide member51does not lift up the turning arm81, the turning arm81is turned by the biasing force of the biasing spring84in a direction in which a leading end of the brush85approaches the LED head14. Accordingly, as illustrated in full line ofFIG. 14, the brush85is pressed against the front surface of the lens array45of the LED head14. Under this state as illustrated inFIG. 14, if a user operates to push or draw out the cleaning operation lever69illustrated inFIG. 11etc., the turning arm81moves in parallel along with the sliding body67. Accordingly, the brush85of the attaching member82moves along the longitudinal direction of the LED head14. Thus, the brush85can smoothly clean the entire front surface of the lens array45.

As illustrated inFIG. 11, etc., slant cams (a parting member or a cam body)88are respectively arranged at each end of a sliding direction of the sliding body67(i.e., a sliding direction of the turning arm81) such that the slant cams88can make contact with the turning arm81. The slant cams88protrude in a ribbed configuration and respectively arranged on the mutually facing surface of the LED supporting frames42and43, which respectively support an end of the cleaning guide rail66. The slant cam88protrudes towards a central side of a slide stroke (a parallel movement stroke of the turning arm81) of the sliding body67.

With the above-described configuration, a state will be described in which the brush85makes contact with the LED head14as illustrated in full line ofFIG. 14, and the brush85cleans according to pushing/drawing out operation of the cleaning operation lever69. When the turning arm81presently positioned near a center of the parallel movement stroke moves towards either end portion of the stroke, the turning arm81makes contact with a sloped surface of the slant cam88. Then, the turning arm81is pressed by the sloped surface of the slant cam88, and turned in a direction against the biasing spring84as illustrated in chained line ofFIG. 14. Thus, the brush85at the leading end of the turning arm81moves away from the LED head14.

Normally, the cleaning operation lever69is pressed into one end of an operation stroke thereof (i.e., pressed into an inner side of the main body513). When cleaning the LED head14, the pushing/drawing out operation of the cleaning operation lever69is repeated for several times, and at last, the cleaning operation lever69is pressed into the inner side of the main body513again. As described above, under a state in which the cleaning operation lever69is pressed in, the turning arm81is turned by the slant cam88against the biasing spring84as illustrated in chain line ofFIG. 14. Thus, even when the slide member51is positioned at the distant position, normally, the brush85is positioned apart from the LED head14by the slant cam88. As a result, the brush85is not worn out by being pressed against the LED head14for a long time. Moreover, the cleaning effect does not decrease.

In particular, when the brush85passes either uneven portion49(illustrated inFIG. 11) respectively arranged at each end of the lens array45of the LED head14, the sloped surface of the slant cam88is set at a position where the brush85is spaced apart from the LED head14. Thus, the brush85can avoid falling off the attaching member82and being damaged by making contact with the uneven portion49.

Further, the slant cams88are protrudingly arranged in the ribbed configuration respectively at the LED supporting frames42and43, which respectively support each of the ends of the cleaning guide rail66. The slant cam88protrudes towards the central side of the parallel movement stroke of the turning arm81(i.e., towards a central side of a slide stroke of the sliding body67). Accordingly, the configuration can be simplified and downsized.

Furthermore, since the attaching member82is removably attached to the turning arm81, when foreign materials such as the toner are accumulated in the brush85, the brush85can be easily exchanged along with the attaching member82. Thus, maintenance can be improved. Moreover, since the attaching member82can be removably attached via the snap fit portion86, attaching screws etc. are not necessary, and the above described exchanging operation can be easily performed.

In addition, the brush85may be directly provided to the turning arm81without the attaching member82. Moreover, in place of the brush85, some fabric may clean the LED head14.

Although the cleaning operation lever69is operated when the slide member51is moved to the distant position (FIG. 14), it is possible that the user performs the pushing/drawing out operation of the cleaning operation lever69by mistake at the adjacent position illustrated inFIG. 11, etc. However, according to the preferred embodiments of the present invention, since the tooth top surface of the rack59is flush with the surface of the slide member51, the turning arm81can smoothly move in parallel along the cleaning guide rail66, intersecting the rack59without damaging the teeth of the rack59and the turning arm81by catching the end surface (the sliding surface)89of the contacting arm83on a portion of the rack59. Moreover, since the cable containing groove75of the base side member52is closed by the lid cover77, and the surface of the lid cover77is also flushed with the surface of the base side member52, the turning arm81can also move in parallel smoothly intersecting a portion of the cable containing groove75.

As illustrated inFIG. 15, the width w1of the sliding surface89at the leading end of the contacting arm83provided to the turning arm81is wider than the width w2of the rack59. Accordingly, even if the sliding surface89at the leading end of the contacting arm83faces a tooth base of the rack59when the contacting arm83intersects the rack59by an erroneous operation of the user as described above, the contacting arm83does not get hooked or caught on the tooth base of the rack59. Therefore, the teeth of the rack59and the turning arm81can be prevented from being damaged.

As illustrated inFIG. 11, etc., when the turning arm81is positioned at the farthest end portion of the parallel movement stroke, the sliding surface89provided to the turning arm81does not overlap with the rack59at all. Even in such a layout, since the parallel movement of the turning arm81is not restricted by the rack59, the LED head14can be reliably cleaned in its entire longitudinal direction. Particularly, according to the preferred embodiments of the present invention, when the turning arm81is positioned at the farthest end portion of the parallel movement stoke, since the brush85is displaced from a cleaned area (substantially corresponds to an area between the uneven portions49) of the LED head14, the entire cleaned area can be reliably cleaned.

The above-described advantage offers greater flexibility to an arranging position of the rack59. Accordingly, as described in the preferred embodiments of the present invention, the racks59may be provided as a pair respectively arranged at each end side of the parallel movement stroke of the turning arm81, and each of the rack59may be respectively arranged at a position closer to the center than the end portion in a longitudinal direction of the cleaned area of the LED head14. Accordingly, with the above-described layout, the LED head supporting mechanism41can be downsized to utilize space effectively.

Further, according to the preferred embodiments of the present invention, the turning arm81is preferably made of polyacetal resin, i.e. the turning arm81is preferably made of a material that slides more easily than that of the slide member51(the base side member52and the leading end side member53). Accordingly, in a case in which the slide member51is switched between the adjacent position and the distant position, or in a case in which the cleaning operation lever69is operated by mistake when the slide member51is at the adjacent position, the turning arm81can smoothly slide with respect to the slide member51. Moreover, compared to a case in which a surface side of the slide member51is made of a material of high slidability, a material cost can be reduced.

Furthermore, the turning arm81including an axial portion (an axial hole) with respect to the sliding body67preferably is integrally formed of polyacetal resin entirely. Accordingly, the turning arm81can smoothly turn, and the sliding surface89with respect to the slide member51can smoothly slide. At the same time, a manufacturing cost can be reduced.

Alternatively, instead of forming the turning arm81with polyacetal resin entirely, for example, only the sliding surface89maybe formed of polyacetal resin. In addition, other resin with high slidability, such as polytetrafluoroethylene resin, may be adopted.

Moreover, the tooth top surface of the rack59may be arranged at a position concave from the surface of the base side member52. In such a case, the contacting arm83of the turning arm81can also pass intersecting the rack59without damaging the teeth of the rack59. However, as described in the preferred embodiments of the present invention, when the tooth top surface of the rack59is flushed with the surface of the base side member52, it is preferable in that the contacting arm83can pass the rack59more smoothly.

Next, a description will be made of positioning of the LED head14with respect to the photoconductive drum12with reference toFIG. 16.FIG. 16illustrates a state in which the slide member51is being switched from the distant position illustrated in FIG.14to the adjacent position illustrated inFIG. 13.

As illustrated inFIG. 16, when the slide member51is inserted into the opening202, the slide member51is supported on a side farther from the photoconductive drum12(i.e., on a rear side) in a cantilever state. Accordingly, there is a problem in that the slide member51slants and lowers a side of the LED head14, an angle of the positioning pin46also slants, and the positioning pin46does not fit into the positioning hole207.

In order to overcome the above-described problem, according to the preferred embodiments of the present invention, when the slide member51is inserted into the opening202and comes close to the adjacent position, a lower surface of a leading end side (the leading end side member53) of the slide member51is guided by an upper surface (a guide surface) of the ribs205. As a result, the leading end side member53is supported by the ribs205, and the positioning pin46provided to the LED head14can be guided to be smoothly inserted into the positioning hole207.

According to the preferred embodiments of the present invention, a sliding direction of the slide member51(the first direction D1) is horizontal. On the other hand, the light irradiating direction from the LED head14to the photoconductive drum12faces obliquely upward, and the direction of the positioning pin46also faces obliquely upward. When the sliding direction of the slide member51is different from the direction of the positioning pin46as described above, the positioning pin46may be required to have a tapered shape and the positioning hole207may be required to have a tapered shape in which an opening end side of the positioning hole207broadens. Otherwise, the positioning pin46cannot be inserted into the positioning hole207. However, in such a state, the positioning cannot be reliably carried out, and oscillation of the LED head14may occur.

According to the preferred embodiments of the present invention, in the slide member51, the leading end side member53moves in the second direction D2with respect to the base side member52. The second direction D2is vertical to the light irradiating direction of the LED head14and to the direction of the positioning pin46. Accordingly, the LED head14can be accurately and smoothly positioned with respect to the photoconductive drum12without bending the slide member51or damaging the positioning hole207by the positioning pin46. Thus, the adjacent position illustrated inFIG. 13can be set.

Since the cylindrical co-rotating roller48is provided between the leading end side member53and the base side member52, the configuration can be simplified, and the leading end side member53can smoothly move via rolling movement of the cylindrical co-rotating roller48. In addition, since the guide plane47on which the cylindrical co-rotating roller48rolls is parallel or substantially parallel to the second direction D2, i.e. parallel or substantially parallel to a moving direction of the leading end side member53, the configuration can be simplified.

The rib205is provided for guiding so that the positioning pin46can be smoothly inserted into the positioning hole207. When the round-shaped portion at the leading end of the positioning pin46is inserted into the positioning hole207, almost simultaneously, a lower side of the leading end side member53moves slightly away from the rib205. Thus, the rib205does not prevent the positioning by the positioning pin46.

According to the preferred embodiments of the present invention, an upper surface of the rib205guides by making contact with the leading end side member53of the slide member51, however, the rib205may guide by directly making contact with the LED head14.

Alternatively, a positioning hole forming member may be provided to a side of the LED head14, and a positioning pin may be provided to a side of the photoconductive drum12. In such a case, the positioning hole forming member corresponds to a positioning body.

Next, a description will be made of assembly of the LED head supporting mechanism41with reference toFIG. 17. As illustrated inFIG. 17, when assembling the LED head supporting mechanism41, the slide member51is inserted between the LED supporting frames42and43in a direction of a heavy-lined arrow, and a side portion of the base side member52fits to the guide rail44.

Accompanying the above-described inserting operation, the rack59engages with the pinion gear57. In such a state, the teeth of the rack59need to be engaged with the teeth58of the pinion gear57at the right phase. For example, even if engagement of the rack59and the pinion gear57is displaced just by one pitch, the LED head14at the adjacent position illustrated inFIG. 13is displaced accordingly, and an electrostatic latent image cannot be normally formed on the photoconductive drum12.

In order to overcome the above-described problem, in the pinion gear57according to the preferred embodiments of the present invention, a pitch p1between teeth (an end portion pitch p1) is greater than a pitch p2between teeth (a normal pitch p2) (i.e., p1>p2). The pitch p1is provided between a tooth58e, which is positioned at the farthest end portion in a circumferential direction of the teeth58aligned in the arc, and the tooth58that is positioned next to the tooth58e. The pitch p2is provided between the other teeth58.

According to the preferred embodiments of the present invention, the pinion gear57is preferably made of synthetic resin in the above-described shape. Moreover, in the leading end side member53, which is positioned on a leading end side in an inserting direction of the slide member51, the concave groove60is arranged such that the concave groove60extends from the rack59. A depth of the concave groove60is substantially the same as a depth of the base surface of the teeth of the rack59.

In the above-described configuration, when inserting the slide member51between the LED supporting frames42and43, a rotational phase (an angle of the pinion gear57) of the operation transmission shaft55is adjusted so that only the tooth58eat the farthest end portion of the pinion gear57is to be positioned inside the concave groove60, and the other teeth58are to be positioned outside the concave groove60. As described above, in the pinion gear57, since the pitch p1between the tooth58e, which is positioned at the farthest end portion of the teeth58aligned in the arc, and the next tooth58, is greater than the pitch p2between the other teeth58, only the tooth58eat the farthest end position can be easily positioned inside the concave groove60.

When inserting the slide member51from the above-described state, a tooth at the leading end portion of the rack59makes contact with the tooth58eat the farthest end portion of the pinion gear57as illustrated inFIG. 17, and the pinion gear57starts rotating at this time. In other words, when the tooth58eat the farthest end portion makes contact with the tooth at the leading end portion of the rack59, a rotational position of the pinion gear57is accurately set. Immediately after the pinion gear57starts rotating, the tooth58next to the tooth58eat the farthest end of the pinion gear57, and its following teeth58sequentially engage with the rack59. Thus, in the LED head supporting mechanism41according to the preferred embodiments of the present invention, the rack59and the pinion gear57can be easily engaged at an accurate position when assembling, and are easily manufactured.

Further, the pitch p1at the end portion is twice as wide as the normal pitch p2(i.e. p1=p2×p2). In other words, after placing the teeth on the pitch equal to the normal pitch p2, the pinion gear57has a tooth cutout portion which is formed by pruning away the tooth next to the tooth at the farthest end. Thus, the shape of the pinion gear57can be simplified, and the pinion gear57can be easily manufactured.

Furthermore, according to the preferred embodiments of the present invention, not only at one end in the circumferential direction of the pinion gear57but also at the other end thereof, the end portion pitch p1is twice as wide as the normal pitch p2. In other words, a plurality of teeth58and the tooth58eof the pinion gear57are symmetrically arranged with respect to a center of the arc. Accordingly, even if the pinion gear57is reversely placed, a portion on which the end portion pitch p1greater than the normal pitch p2is arranged faces the rack59. Therefore, since a user does not have to consider an attaching direction of the pinion gear57when assembling, components can be conveniently handled, and assembling error can be prevented.

The above-described configuration is effective in that when the racks59are preferably provided as a pair, and a plurality of the pinion gears57are provided to respectively engage with the racks59as in the preferred embodiments, identical components can be used as the pinion gear57, and control man hours of the components can be reduced. Further, according to the preferred embodiments of the present invention, the racks59have each respective tooth at a similar position with respect to each other, and the pinion gears57are fixed to the operation transmission shaft55similarly in phase with respect to each other. Therefore, the pinion gears57can easily and simultaneously engage with the racks59, respectively

Alignment of the teeth58of the pinion gear57may not be symmetrical. The end portion pitch p1is not limited to be twice as wide as the normal pitch p2, and the end portion pitch p1is preferably greater than the normal pitch p2(i.e., p1>p2). However, it is preferable that the end portion pitch p1is an integral multiple of the normal pitch p2.

Instead of providing two racks59and two pinion gears57respectively as a pair, more than three or only one rack(s)59or pinion gear(s)57may be provided. When providing the leading end side member53and the base side member52such that the leading end side member53does not move with respect to the base side member52, the rack59may extend to the base side member52.

The configuration according to the preferred embodiments of the present invention can be applied not only to the copy-and-facsimile MFP501but also to a printer, a copying machine, and a facsimile machine or the like.