JP2011158773A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus where a plurality of optical scanners are inserted from one side surface of a casing in line and attaching/detaching work of the plurality of optical scanners and positioning work during attaching can be easily performed. <P>SOLUTION: In the image forming apparatus, a plurality of optical scanners 3a and 3b are inserted from one side surface of the casing 1 in line. The image forming apparatus includes a coupling means and a positioning means. The coupling means has a coupling claw 35 disposed in the backward optical scanner 3b of the insertion direction and a coupling hole 36 disposed in the forward optical scanner 3a of the insertion direction, and inter-couples the optical scanners 3a and 3b in a butted state. The positioning means has a positioning claw 37 disposed in the foremost optical scanner 3a of the insertion direction and a positioning hole 38 disposed in a wall surface 13 abutting on the optical scanner 3a, and determines the position of the horizontal direction (insertion direction and lateral direction) of the optical scanner 3a when the optical scanner 3a is inserted to a determined attaching position. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an electrophotographic image forming apparatus, and more particularly, to an image forming apparatus including a plurality of optical scanning devices that scan light beams for writing an electrostatic latent image on a photosensitive drum.

An electrophotographic image forming apparatus such as a printer or a copying machine includes a photosensitive drum, an exposure device for writing an electrostatic latent image on the photosensitive drum, and development for developing the electrostatic latent image on the surface of the photosensitive drum as a toner image. Equipment and the like.
The exposure apparatus includes a laser light source that emits a beam light for writing an electrostatic latent image, and an optical system that scans in the rotation axis direction (main scanning direction) of the photosensitive drum while reflecting the emitted beam light. And an optical scanning device for writing an electrostatic latent image on the surface of the photosensitive drum by the scanned light beam. The optical system that scans the light beam is scanned by an optical scanner including a polygon mirror and its driving motor, an fθ lens that stabilizes the scanning speed of the beam light scanned in a fan shape in the main scanning direction, and the like. A reflection mirror that reflects the beam light is included.

In recent years, so-called tandem image forming apparatuses are provided with a photosensitive drum, a developing device, etc., as disclosed in Patent Document 1, for example, and write and develop an electrostatic latent image on the photosensitive drum. After that, many image forming units for transferring an image to an intermediate transfer belt are provided, and the above-described optical scanning device is disposed below the image forming unit.
Accordingly, the secondary transfer process for transferring the toner image on the intermediate transfer belt from the primary transfer process for transferring the toner image to the intermediate transfer belt from the image forming unit to the recording paper vertically conveyed upward. Can be shortened. As a result, there is an advantage that the time from the start of the image forming process to the completion of the image forming process for the first recording sheet is shortened, and the processing efficiency is improved.
However, in an image forming apparatus in which such an optical scanning device is disposed below the image forming unit, the upper image forming unit, intermediate transfer belt, or the like is used in order to remove the optical scanning device for maintenance of the optical scanning device. It took a lot of time to remove it.
For this reason, a contrivance is made such that a detachable opening is provided in the housing of the image forming apparatus so that the detaching operation can be performed from the side of the image forming apparatus. The operator can easily attach / detach the optical scanning device by inserting / removing the optical scanning device laterally from the attachment / detachment opening portion even if there is an image forming unit or the like above.

JP 2006-231707 A JP 2009-96037 A

By the way, from the viewpoint of downsizing and cost reduction of the apparatus, there are many apparatuses in which the optical scanning apparatus is divided into a plurality of parts as in the image forming apparatus disclosed in Patent Document 2. In this way, even in an image forming apparatus including a plurality of optical scanning devices below the image forming unit, if possible, optical scanning can be performed from a detachable opening provided on the side surface of the housing, similarly to the image forming apparatus described in Patent Document 1. It is desirable to configure the device to be inserted and removed.
However, since there are many members such as a paper feeding device, a fixing device, and a conveying means in the housing, providing a detachable opening for each of the plurality of optical scanning devices is a problem in terms of space in the housing. Therefore, it is difficult. Therefore, as a second best measure, a method of inserting / removing a plurality of optical scanning devices from one attachment / detachment opening provided on the end side of the optical scanning devices arranged in a row is adopted. In this method, a plurality of optical scanning devices are sequentially inserted and attached from one attachment / detachment opening, and are sequentially pulled out from one attachment / detachment opening and removed. For this reason, it is difficult for the operator to reach the optical scanning device (the optical scanning device on the back side when viewed from the attachment / detachment opening) arranged on the front side in the insertion direction. In other words, there is a problem that workability of pulling out the optical scanning device on the back side and positioning work at the time of mounting is extremely poor.
Further, even if the plurality of optical scanning devices are not image forming devices arranged below the image forming unit, other members such as an image reading device such as a multi-function device are located above the plurality of optical scanning devices. In the image forming apparatus in which the optical scanning device is inserted and removed from the side surface of the housing, there is the same problem as described above.
Accordingly, the present invention has been made in view of the above circumstances, and an object of the present invention is to provide a plurality of light beams in an image forming apparatus in which a plurality of optical scanning devices are inserted in a row from one side surface of a housing. An object of the present invention is to provide an image forming apparatus capable of easily performing a detaching operation of a scanning device and a positioning operation at the time of mounting.

In order to achieve the above object, the present invention includes a plurality of image forming units each having at least a photosensitive drum and a plurality of optical scanning devices that cause the photosensitive drum to scan with beam light. Is basically inserted and mounted in a direction perpendicular to the rotation axis direction of the photosensitive drum from one side surface of the housing.
Of the plurality of optical scanning devices, two optical scanning devices adjacent to each other in the insertion direction are connected by a connecting means in a state where they are in contact with each other. Further, among the plurality of optical scanning devices, the horizontal position of the foremost optical scanning device in the insertion direction is the position of the foremost optical scanning device when inserted to a predetermined mounting position inside the housing. Positioning is performed by positioning means for determining a horizontal position. By providing the connecting means, two adjacent optical scanning devices in the front and rear in the insertion direction are connected in contact with each other, so that the optical scanning device in the front in the insertion direction (the optical scanning device on the back side) is an operator. Is inserted to the specified mounting position simply by pushing in the optical scanning device at the rear in the insertion direction (front optical scanning device), and the operator pulls out the optical scanning device on the rear side by pulling out the optical scanning device on the rear side. The optical scanning device is also connected by the connecting means, pulled out, and taken out. That is, a plurality of optical scanning devices can be easily inserted / removed without requiring the operator to reach the back of the housing.
Further, by providing the positioning means, the foremost optical scanning device in the insertion direction (the innermost optical scanning device) is inserted in the horizontal direction (insertion direction) when inserted to a predetermined mounting position inside the housing. And a direction parallel to the rotational axis direction of the photosensitive drum). That is, when the innermost optical scanning device reaches the predetermined mounting position, the position in the horizontal direction is determined as it is, so that the operator can easily determine the position of the innermost optical scanning device by simply inserting it. Can do.
The horizontal direction here refers to a direction parallel to the insertion direction and the rotation axis direction of the photosensitive drum as described above, and does not necessarily indicate a direction perpendicular to the ground axis. If the connecting direction of the optical scanning device is inclined with respect to the ground axis, this horizontal direction is also inclined.
By having both the connecting means and the positioning means, the operator can easily insert and position the innermost optical scanning device up to a predetermined mounting position by pushing in the front optical scanning device. be able to. Further, since the back side optical scanning device and the near side optical scanning device are connected in contact with each other, the farthest side optical scanning device is positioned in the horizontal direction, and the near side optical scanning device is also positioned. Positioning is also performed sequentially.
As described above, it is possible to easily perform the attaching / detaching operation and the positioning operation at the time of mounting the plurality of optical scanning devices that are inserted and mounted in a row horizontally from one side surface of the housing.

The connecting means includes a front engagement hole or a front engagement claw provided at a rear end portion of the optical scanning device located in front of the insertion direction among two adjacent optical scanning devices in the front and rear of the insertion direction, and insertion A so-called snap-fit type, which is provided at the front end of the optical scanning device located rearward in the direction and includes a rear engagement claw or a rear engagement hole that engages with the front engagement hole or the front engagement claw. Can be adopted.
In the case of the snap-fit method, the front or rear engagement claw is made of an elastic member, and when the two optical scanning devices adjacent to the front and rear in the insertion direction approach each other, the rear side or front side engagement When the two optical scanning devices come into contact with each other while being deformed into a joint hole, the two optical scanning devices return to their original shape due to elasticity and connect the two optical scanning devices.
Since the connecting means is of such a snap-fit type, the operator simply inserts a plurality of optical scanning devices in sequence, and the optical scanning devices on the back side and the near side are contacted automatically at the same time. Is done. Conversely, the connected front and rear optical scanning devices return to their original shape due to their elasticity after the front or rear engagement pawl is pushed into the rear or front engagement hole as described above. It will not come off even if pulled. For this reason, the operator simply pushes the optical scanning device one by one, does not need to bother to connect, and pulls out the optical scanning device on the near side, so that the optical scanning device on the back side Since it is pulled out sequentially, a plurality of optical scanning devices can be inserted and removed more easily.
Further, as the positioning means, a snap-fit type similar to the connecting means can be adopted. However, in this case, when the foremost optical scanning device in the insertion direction is inserted into the housing up to a predetermined mounting position in the housing, there is a wall surface against which the front end of the optical scanning device abuts. It must be formed.
Positioning means for positioning the foremost optical scanning device with respect to the wall surface is provided at a foremost engagement hole provided in the wall surface and a front end portion of the foremost optical scanning device in the insertion direction. It is conceivable that the foreground engaging pawl is inserted into and engaged with the side engaging hole.
Thus, the foremost engaging claw and the foremost engaging hole engage with the front or rear engaging claw in the same manner as the rear or front engaging hole, so that the foremost optical scanning in the insertion direction is performed. The device is positioned horizontally.
In the connection using the engaging claw and the engaging hole as described above, it is necessary to position each optical scanning device in the vertical direction (the direction of the surface that supports the connected optical scanning device from below). In order to prevent the occurrence of such an error in the vertical direction, a guide member for forming a horizontal plane is provided inside the casing, and the plurality of optical scanning devices are inserted by sliding on the horizontal plane. Is preferred.
The plurality of optical scanning devices are smoothly inserted into the predetermined mounting position along the guide member and are disposed on the horizontal plane, so that the entire optical scanning device is positioned in the vertical and horizontal directions.
The horizontal plane and the horizontal direction referred to here mean a plane and a direction parallel to the insertion direction and the rotation axis direction of the photosensitive drum, as in the horizontal direction described above.

According to the present invention, among a plurality of optical scanning devices that are inserted and mounted in a row in a direction orthogonal to the rotation axis direction of the photosensitive drum from one side surface of the housing, two adjacent optical scanning devices that are adjacent in the insertion direction are adjacent to each other. By providing the connecting means for connecting the two optical scanning devices in contact with each other, the two adjacent optical scanning devices in the insertion direction are connected in contact with each other. (The optical scanning device on the back side) is inserted to a predetermined mounting position by simply performing a simple operation in which the operator pushes the optical scanning device (front optical scanning device) behind in the insertion direction. By pulling out the side optical scanning device, the back side optical scanning device is also connected by the connecting means, and is pulled out and taken out together. That is, a plurality of optical scanning devices can be easily inserted / removed without requiring the operator to reach the back of the housing.
Further, by providing the positioning means, the foremost optical scanning device in the insertion direction (the innermost optical scanning device) is inserted in the horizontal direction (insertion direction) when inserted to a predetermined mounting position inside the housing. And a direction parallel to the rotational axis direction of the photosensitive drum). That is, when the innermost optical scanning device reaches the predetermined mounting position, the position in the horizontal direction is determined as it is, so that the operator can easily determine the position of the innermost optical scanning device by simply inserting it. Can do.
By having both the connecting means and the positioning means, the operator can easily insert and position the innermost optical scanning device up to a predetermined mounting position by pushing in the front optical scanning device. be able to. Further, since the back side optical scanning device and the near side optical scanning device are connected in contact with each other, the farthest side optical scanning device is positioned in the horizontal direction, and the near side optical scanning device is also positioned. Positioning is also done.
As described above, it is possible to easily perform the attaching / detaching operation and the positioning operation at the time of mounting the plurality of optical scanning devices that are inserted and mounted in a row horizontally from one side surface of the housing.
Further, since the connecting means is of a snap-fit type, the operator simply inserts a plurality of optical scanning devices in sequence, and the optical scanning devices on the back side and the near side are automatically connected at the same time as they abut. . Conversely, the connected front and rear optical scanning devices return to their original shape due to their elasticity after the front or rear engagement pawl is pushed into the rear or front engagement hole as described above. It will not come off even if pulled. For this reason, the operator simply pushes the optical scanning device one by one, does not need to bother to connect, and pulls out the optical scanning device on the near side, so that the optical scanning device on the back side Since it is pulled out sequentially, a plurality of optical scanning devices can be inserted and removed more easily.

1 is a schematic side sectional view showing an internal structure of an image forming apparatus according to the present invention. FIG. 6 is a view for explaining an attaching / detaching operation of a plurality of optical devices of the image forming apparatus according to the present invention. FIG. 3 is a diagram illustrating an example of a connecting unit of the image forming apparatus according to the present invention. FIG. 6 is a view for explaining the operation of the connecting means of the image forming apparatus according to the present invention. FIG. 6 is a view for explaining the removing operation of the positioning means of the image forming apparatus according to the present invention.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings so that the present invention can be understood. The following embodiment is an example embodying the present invention, and does not limit the technical scope of the present invention.
First, the outline of the image forming apparatus X according to the embodiment of the present invention will be described. The image forming apparatus X will be described by taking a printer as an example, but is not limited to this, and may be a copier, a facsimile machine, or a multifunction machine.
1 is a schematic cross-sectional view of the image forming apparatus X as viewed from the right side. In FIG. 1, the left side is the front (front) side of the image forming apparatus X, and the right side is the back (rear) side of the image forming apparatus X. . Further, the horizontal direction of the image forming apparatus X means a direction orthogonal to the paper surface in FIG.

The image forming apparatus X is a so-called tandem type image forming apparatus. As shown in FIG. 1, the image forming apparatus X includes four image forming units 2, two optical scanning devices 3a and 3b, and an intermediate transfer as shown in FIG. Belt 4. Further, a paper feeding device 5, a secondary transfer device 6, a fixing device 7, a paper discharge unit 8 and the like are provided.
Each image forming unit 2 writes a photosensitive drum 21 that carries a toner image, a charging device that charges the surface of the photosensitive drum 21, and irradiation (exposure) of the laser beam on the surface of the charged photosensitive drum 21. A developing device for developing the electrostatic latent image with toner, a primary transfer device for transferring the toner image developed and formed on the photosensitive drum 21 to the intermediate transfer belt 4, and toner remaining on the photosensitive drum 21. A cleaning device and the like for removal are provided.
Here, the four image forming units 2 execute an image forming process for transferring toner images of black, yellow, cyan, and magenta to the intermediate transfer belt 4, respectively. 4 in the order of black, yellow, cyan, and magenta.
The photosensitive drums 21 of the four image forming units 2 are arranged with the left-right direction of the image forming apparatus X as the rotation axis direction so that the rotation axes thereof are parallel to each other.
Note that the image forming process of these image forming units 2 is not different for each color but has the same configuration, and is therefore generally referred to as an image forming unit 2.
The two optical scanning devices 3a and 3b are disposed below the image forming unit 2, and one of them is a laser beam (beam) for writing an electrostatic latent image on the photosensitive drum 21 for black and yellow. 1 is a light scanning device 3a (right side in FIG. 1), and the other is a light scanning device 3b that scans a cyan and magenta photosensitive drum 21 with laser beam light for writing an electrostatic latent image. (Left side in FIG. 1). Since the optical scanning devices 3a and 3b have the same configuration, they are collectively referred to as the optical scanning device 3.
The intermediate transfer belt 4 is an endless belt made of a material such as rubber or urethane.
The drive roller 41 and the driven roller 42 are wound around and supported, and are driven to rotate.

The image forming operation on the transfer material such as recording paper by the image forming apparatus X is not particularly different from that of a general image forming apparatus. The outline of the operation is as follows. As the laser beam is rotated, the laser beam is irradiated by the optical scanning device 3 to be exposed, and an electrostatic latent image is written on the surface of the photosensitive drum 21. This electrostatic latent image is developed by a developing device, and a toner image is formed on the surface of the photosensitive drum 21. This is performed in the image forming unit 2 for each color.
The toner images formed on the surface of the photosensitive drums 21 of the respective colors are sequentially transferred and stacked on the intermediate transfer belt 4 by the respective primary transfer devices, and a full color toner image is formed on the intermediate transfer belt 4. The full-color toner image formed on the intermediate transfer belt 4 is transferred by the secondary transfer device 6 onto the recording paper fed one by one from the paper feeding device 5. Thereafter, the toner is fixed on the recording paper by the fixing device 7, and the recording paper on which the image is formed is discharged to the paper discharge unit 8.
As described above, the image forming apparatus X forms a color image on a transfer material such as recording paper.

  The optical scanning device 3 scans a light source (not shown) such as a laser diode that emits laser beam light for writing an electrostatic latent image, or the laser beam light in the rotation axis direction (main scanning direction) of the photosensitive drum 21. For example, an optical system composed of various optical devices, and an optical casing 31 for housing the optical system. The optical equipment that constitutes the optical system includes a collimator lens (not shown) that collimates the laser beam light emitted from the light source, a cylindrical lens (not shown) that condenses the parallel light into a linear shape, and reflects the laser beam light. An optical scanner 32 equipped with a polygon mirror that rotates while rotating and a motor for driving the mirror, an fθ lens 33 that makes the scanning speed of the laser beam scanned in a fan shape constant in the main scanning direction, and a reflection that reflects the scanned laser beam. A mirror 34 and the like are included, and these are accommodated in the optical casing 31. The light source may be housed in the optical housing 31, but may be housed in a holding member dedicated to the light source attached to the outer surface of the optical housing 31.

The optical scanning device 3 is often detached from the housing 1 for cleaning or maintenance when the above-described optical system is contaminated with dust such as toner.
Hereinafter, the detachment of the optical scanning devices 3a and 3b will be described.
In the image forming apparatus X of the present embodiment, as described above, the four image forming units 2 are arranged such that the rotation axis direction of each photosensitive drum 21 is parallel to the left-right direction of the image forming apparatus X. The two optical scanning devices 3a and 3b are disposed below the optical scanning devices 3a and 3b.
Therefore, the housing 1 has a front cover 11 that can be opened and closed and an opening that can be opened and closed inside the housing 1 so that the two optical scanning devices 3a and 3b can be detached from the front surface (front side surface) of the housing 1. An attachment / detachment opening 12 covered with a cover 12a is provided (see FIG. 1).
The two optical scanning devices 3a and 3b are attached / detached from the attaching / detaching opening 12 with the front cover 11 and the opening cover 12a being opened. Mounting of the optical scanning device 3 is performed by inserting 3a and 3b in order from the detachable opening 12, and detaching is performed in the order of 3b and 3a. In the following description, the insertion direction means the front-rear direction (the left-right direction in FIG. 1) of the image forming apparatus X, the front in the insertion direction means the rear side of the image forming apparatus X, and the rear in the insertion direction means the image forming apparatus X. It means the front side.
Although the front cover 11 and the opening cover 12a are both rotated and opened and closed in FIG. 1, the present invention is not limited to this. May be used. The front cover 11 may also be used as a paper feed tray connected to the paper feeder 5.

A horizontal rail 9 that forms a horizontal plane so as to extend forward from the lower end of the attachment / detachment opening 12 in the insertion direction is disposed inside the housing 1. As shown in FIG. 2, when the optical scanning devices 3a and 3b are slid on the horizontal rail 9 and inserted in the insertion direction, the optical scanning devices 3a and 3b are not only inserted smoothly but also vertically by the own weight of the optical scanning devices 3a and 3b. Directional positioning is made. Although not shown, for example, if a highly accurate guide member such as a roller follower is provided on the back surface of the optical casing 31 of the optical scanning device 3 as a wheel, positioning in the vertical direction is easily performed. The horizontal rail 9 is not particularly limited, but, for example, if it is configured to form a horizontal plane by arranging plate members side by side as schematically shown in FIG. 2, it is possible to contribute to a reduction in processing costs and assembly adjustment man-hours. There is. In addition to this, when a groove-like recess extending in the insertion direction is provided and a horizontal surface is formed on the bottom surface of the groove-like recess, there is an advantage that the side surface of the recess can be positioned in the left-right direction.
Here, the horizontal plane means a plane parallel to the insertion direction and the rotation axis direction of the photosensitive drum 21, and does not necessarily indicate a direction perpendicular to the ground axis. If the connecting direction of the optical scanning devices 3a and 3b is inclined with respect to the ground axis, the horizontal plane is also inclined. The vertical direction means a direction perpendicular to the horizontal plane. Hereinafter, the terms “horizontal” and “vertical” in this specification have the same meaning.

A wall surface 13 perpendicular to the horizontal rail 9 is formed at the front end of the horizontal rail 9 in the insertion direction. The wall surface 13 is a front-rear direction positioning member with which the front end portion of the optical scanning device 3a comes into contact when the optical scanning device 3a disposed in front of the insertion direction is inserted to a predetermined mounting position. In other words, the wall surface 13 is a member that determines the mounting position of the optical scanning device 3a in the insertion direction.
In this embodiment, the wall surface 13 is a plate-like member arranged perpendicular to the horizontal rail 9 along the front end portion of the optical scanning device 3a that forms a plane perpendicular to the horizontal rail 9. It is not limited to the shape following the front end of the scanning device 3a.

The image forming apparatus X according to the present invention includes, for example, a connection claw 35 (an example of a rear engagement claw) provided at the front end of the optical scanning device 3b behind the insertion direction, as shown by an arrow in FIG. A connecting means is provided at the rear end of the optical scanning device 3a forward in the direction, and includes a connecting hole 36 (an example of a front engaging hole) that engages with the connecting claw 35. This connecting means connects two optical scanning devices 3 adjacent to each other in the insertion direction, that is, the optical scanning device 3a and the optical scanning device 3b in contact with each other. The connecting claw 35 may be provided at the rear end portion (being a front side connecting claw) of the optical scanning device 3a, and the connecting hole 36 may be provided at the front end portion (being a rear side connecting hole) of the optical scanning device 3b. Further, the connecting means is not necessarily limited to the connecting claw 35 and the connecting hole 36, and may be a catch clip, for example.
Since the optical scanning device 3a and the optical scanning device 3b are connected in contact with each other, the operator simply pushes the optical scanning device 3b at the rear in the insertion direction and moves forward in the insertion direction. A certain optical scanning device 3a can be inserted to a predetermined mounting position, and by pulling out the optical scanning device 3b, the optical scanning device 3a can be pulled out and removed together. That is, all of the plurality of optical scanning devices 3 can be easily inserted / removed without the operator having to reach the back of the housing 1.
It is preferable that the connection claw 35 and the connection hole 36 constituting the connection means be of a so-called snap fit type. In the snap-fit method, an engaging part made of an elastic member is inserted into an engaged part while being elastically deformed. When the insertion is completed, the engaging part returns to its original shape by its elastic force and is engaged. Engage with a part. In the present embodiment, the connecting claw 35 corresponds to this engaging part, and the connecting hole 36 corresponds to the engaged part.
3 and 4 show an example of the snap-fitting type connection claw 35 and the connection hole 36, and the engagement operation will be described. 3A is a perspective view showing the connection claw 35, FIG. 3B is a cross-sectional view of the connection claw 35, and FIGS. 4A to 4C start insertion of the connection claw 35 into the connection hole 36. FIG. It is a figure which shows from insertion completion to insertion completion.
The connecting claw 35 is provided so as to protrude forward from the plane of the front end of the optical scanning device 3b in the insertion direction, and has a tip A that has a conical appearance and an arrow shape in cross section, and a cylindrical shape. It consists of inlay part B. The conical portion of the tip portion A has a flexible portion A1 at the rear in the insertion direction, and is provided with several cuts A2 along the generatrix. The diameter of the circle formed by the rear end portion in the insertion direction of the flexible portion A1, that is, the circle corresponding to the bottom surface of the conical portion, is larger than the diameter of the spigot portion B. The connecting hole 36 is a hole provided in the plane at the rear end of the optical scanning device 3a in the insertion direction, and has a circular shape with a diameter that fits the inlay portion B.
First, when the optical scanning device 3b approaches the optical scanning device 3a, the tip A of the coupling claw 35 enters (see FIG. 4A). Further, when the two optical scanning devices 3a and 3b approach each other, the connecting claw 35 is inserted into the connecting hole 36 while the flexible portion A1 of the connecting claw 35 is restricted by the connecting hole 36 and deformed (FIG. 4B). )reference). When the optical scanning devices 3a and 3b come into contact with each other, the insertion of the coupling claw 35 into the coupling hole 36 is completed, and the flexible portion A1 returns to its original shape by the elastic force. At this time, the rear end of the flexible portion A1 in the insertion direction is engaged with the optical scanning device 3a, and the optical scanning devices 3a and 3b are connected in contact with each other.
As described above, when the connecting means (the connecting claw 35 and the connecting hole 36) are of the snap-fit type, the operator simply inserts the plurality of optical scanning devices 3a and 3b in sequence, and the optical scanning devices 3a and 3b. Are automatically connected as soon as they abut. On the contrary, after the connecting claw 35 is pushed into the connecting hole 36, the connected optical scanning devices 3a and 3b will not come off even if they return to their original shape due to their elasticity. Therefore, the operator simply pushes the optical scanning devices 3a and 3b one by one, does not need to bother to connect them, and only pulls out the optical scanning device 3b on the near side. Since the optical scanning device 3a is also sequentially pulled out, a plurality of optical scanning devices 3 can be more easily inserted and removed.
In addition, the shape of the connection nail | claw 35 and the connection hole 36 is not limited to what is shown in FIG. For example, if the connecting claw 35 has the shape shown in FIGS. 3 and 4 and the connecting hole 36 is a vertically long slot (elliptical hole) as shown in FIG. 2, the connecting claw 35 and the connecting hole 36 are arranged in the vertical direction. Since there is a clearance, there is an advantage that it is easy to insert. In addition to this, the connecting claw 35 may be a claw type so that it can be easily molded.

The image forming apparatus X is provided on the wall surface 13 and a positioning claw 37 (an example of the foremost engaging claw) provided at the front end of the optical scanning device 3a forward in the insertion direction, for example, as shown in FIG. , Positioning means including a positioning hole 38 (an example of the foremost engagement hole) that engages with the positioning claw 37 is provided. This positioning means is provided in the horizontal direction of the optical scanning device 3a when the front end portion of the optical scanning device 3 in the insertion direction, that is, the front end of the optical scanning device 3a contacts the wall surface 13 among the plurality of optical scanning devices 3. The position in the insertion direction and the rotation axis direction of the photosensitive drum is determined.
That is, when the optical scanning device 3a comes into contact with the wall surface 13, the position in the horizontal direction (the insertion direction and the rotation axis direction of the photosensitive drum) is determined as it is, so that the operator can place the optical scanning device 3a into contact with the wall surface 13. It is possible to position the optical scanning device 3a only by inserting up to.
The positioning claw 37 and the positioning hole 38 that constitute the positioning means can be of a snap-fit type, similarly to the coupling claw 35 and the coupling hole 36 that constitute the coupling means.
As shown in FIGS. 3 and 4, if a positioning claw 37 similar to the coupling claw 35 is provided on the plane at the front end in the insertion direction of the optical scanning device 3a and a positioning hole 38 similar to the coupling hole 36 is provided in the wall surface 13, the optical scanning is performed. The position in the horizontal direction is automatically determined at the same time when the device 3a contacts the wall surface 13. That is, since the flexible portion A1 of the positioning claw 37 engages with the wall surface 13, the optical scanning device 3a is regulated in the insertion direction while being in contact with the wall surface 13, and positioned in the insertion direction. Then, the inlay portion B is fitted into the positioning hole 38, whereby the positioning in the left-right direction (the rotation axis direction of the photosensitive drum 21) is performed.
Moreover, in this embodiment, since the spigot part B and the positioning hole 38 are circular shapes that fit each other, positioning in the vertical direction as well as in the left-right direction can be performed.
The shapes of the positioning claw 37 and the positioning hole 38 are not particularly limited as in the case of the connecting claw 35 and the connecting hole 36. For example, the positioning hole 38 is similar to the connecting hole 36 as shown in FIG. It is good also as an elongate vertically long hole (elliptical hole).
Here, if the positioning means is of the snap fit type as described above, the positioning claw 37 and the positioning hole 38 must be disengaged in order to remove the optical scanning device 3a from the wall surface 13. For this, for example, a cup-shaped jig T having the same inner diameter as the diameter of the positioning hole 38 as shown in FIG. 5 is used. If the jig T is placed on the positioning claw 37 from the front in the insertion direction of the wall surface 13, the flexible portion A1 can be deformed and the engagement is released, so that the optical scanning device 3a can be pulled out easily.
As described above, since the image forming apparatus X has both the connecting means including the connecting claw 35 and the connecting hole 36 and the positioning means including the positioning claw 37 and the positioning hole 38, the operator pushes the optical scanning device 3b. The optical scanning device 3a can be easily inserted into a predetermined mounting position and can be easily positioned.
Further, since the optical scanning device 3a and the optical scanning device 3b are connected in contact with each other, the optical scanning device 3a is positioned in the horizontal direction, and the optical scanning device 3b is also positioned in the horizontal direction.
The positioning means is not necessarily limited to the positioning claw 37 and the positioning hole 38. For example, the optical scanning device 3a is guided inside a U-shaped frame that is open at the rear in the insertion direction, and is positioned by pressing the optical scanning device 3a with a positioning plunger or the like from the left and right sides of the frame. It may be.

Further, the image forming apparatus X may be provided with a second positioning hole 39 on the plane at the rear end in the insertion direction of the optical scanning device 3b and a second positioning claw (not shown) on the opening cover 12a. . As a result, the plurality of optical scanning devices 3 positioned in the horizontal direction by the positioning claws 37 and the positioning holes 38 are also positioned at the rear end portion in the insertion direction, so that the optical scanning by the vibration of the image forming apparatus X itself or the like. The horizontal displacement of the device 3 is less likely to occur.
If the connecting claw 35 and the positioning claw 37 and the connecting hole 36 and the second positioning hole 39 have the same shape, the optical casings 31 of the optical scanning devices 3a and 3b can be made common. It can also contribute to reducing manufacturing costs.
Further, after the optical scanning devices 3a and 3b are inserted and positioned, there may be provided fixing means for pressing the optical scanning devices 3a and 3b from the vertical direction. By providing the fixing means, the positioned optical scanning devices 3a and 3b can be securely fixed, so that the optical scanning device 3 can be prevented from being displaced due to vibrations of the image forming apparatus X itself. Therefore, it is possible to prevent a decrease in the accuracy of writing the electrostatic latent image on the photosensitive member 21, that is, a decrease in image quality.
Examples of the fixing means include a clamp that vertically holds the optical scanning device 3 between the horizontal rail 9 and the like, and a bolt that is inserted from above the housing 1 and fastens the optical scanning device 3 to the horizontal rail 9 and the like.

  The image forming apparatus X described above includes the two optical scanning devices 3 below the plurality of image forming units 2, but this is only an embodiment, and the present invention is limited to this. It is not a thing. The present invention can be applied to, for example, an image forming apparatus including one optical scanning device for each color, that is, four optical scanning devices. Further, even if the optical scanning device is disposed above the image forming unit, a plurality of optical scanning devices are arranged on the side surface of the housing in a multifunction device or the like in which the image reading device is disposed at the top of the housing. It is applicable also to what is desorbed from.

DESCRIPTION OF SYMBOLS 1 Case 13 Wall surface 2 Image forming unit 21 Photosensitive drum 3 Optical scanning device 35 Connection nail | claw (an example of a rear side engagement nail)
36 connection hole (an example of front engagement hole)
37 Positioning claw (an example of the foremost engaging claw)
38 Positioning hole (an example of the foremost engagement hole)
9 Horizontal rail (guide member)
X image forming device

Claims (4)

A plurality of image forming units having at least a photosensitive drum and a plurality of optical scanning devices for scanning the photosensitive drum with beam light are provided inside the housing,
In the image forming apparatus in which the plurality of optical scanning devices are inserted and mounted in a row from a side surface of the housing in a direction orthogonal to the rotation axis direction of the photosensitive drum,
A coupling means for coupling two optical scanning devices adjacent to each other before and after in the insertion direction among the plurality of optical scanning devices;
Positioning that determines the horizontal position of the foremost optical scanning device when the foremost optical scanning device in the insertion direction is inserted to a predetermined mounting position in the housing among the plurality of optical scanning devices. And an image forming apparatus. The connecting means includes a front engagement hole or a front engagement claw provided at a rear end portion of the optical scanning device located in front of the insertion direction, and the insertion direction, of two optical scanning devices adjacent to each other in the insertion direction. A rear engagement claw or a rear engagement hole which is provided at a front end portion of the optical scanning device located rearward and which engages with the front engagement hole or the front engagement claw;
The front and rear engagement claws are made of an elastic member, and are deformed into the rear or front engagement holes when two adjacent optical scanning devices approaching in the insertion direction approach each other. 2. The image forming apparatus according to claim 1, wherein when the two optical scanning devices are inserted, the two optical scanning devices return to their original shapes by elasticity and are connected so as not to disengage the two optical scanning devices. A wall surface is formed in the housing so that when the foremost optical scanning device in the insertion direction is inserted to a predetermined mounting position inside the housing, the front end of the optical scanning device abuts.
The positioning means is provided at the foremost engagement hole provided in the wall surface and at the front end of the foremost optical scanning device in the insertion direction, and is inserted into and engaged in the foremost engagement hole. Consisting of engaging claws,
The foremost engaging claw is made of an elastic member, and is deformed into the foremost engaging hole when the front end of the foremost optical scanning device in the insertion direction approaches the wall surface to come into contact with the wall surface. When the front end of the foremost optical scanning device in the insertion direction comes into contact with the wall surface, it returns to its original shape due to elasticity, and the horizontal positioning of the foremost optical scanning device in the insertion direction is performed. The image forming apparatus according to claim 1. The image forming apparatus according to claim 1, wherein the plurality of optical scanning devices are inserted by sliding on a horizontal plane formed by a guide member provided inside the housing.

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