CN211628008U - Image forming apparatus with a toner supply device - Google Patents

Abstract

The utility model provides an image forming device. An image forming apparatus of an embodiment includes: a photosensitive drum; an exposure portion facing the photosensitive drum and fixed in position in a first direction with respect to the image forming apparatus, the exposure portion having protrusions formed at both ends in the first direction; a housing that holds the photosensitive drum, and in which inclined portions that face the protruding portions are formed at both ends in the first direction, respectively, and the inclined portions are in contact with the protruding portions so as to be slidable on the protruding portions; a biasing member that presses the exposure portion toward the housing; and a first adjusting portion provided on the housing, adjusting a position of the housing in the first direction with respect to the image forming apparatus. Through the utility model discloses, can adjust the distance between exposure portion and the sensitization drum to form the image that the quality is good.

Description

Image forming apparatus with a toner supply device

Technical Field

Embodiments of the present invention relate to an image forming apparatus.

Background

In the related art, an image forming apparatus exposes a photosensitive drum by an exposure portion to form an electrostatic latent image on the photosensitive drum and prepare for subsequent image transfer. In order to miniaturize the image forming apparatus, a compact system in which the distance between the exposure portion and the photosensitive drum is shortened may be used. At this time, if the distance (focal distance) between the exposure portion and the photosensitive drum is shifted, an electrostatic latent image formed on the photosensitive drum may be incorrect, and the quality of the final image formation may be affected, resulting in poor image quality.

SUMMERY OF THE UTILITY MODEL

The utility model provides an image forming apparatus for preventing image quality degradation through adjusting the focus distance between exposure portion and the sensitization drum.

An image forming apparatus of an embodiment includes: a photosensitive drum; an exposure portion that faces the photosensitive drum and is fixed in position in a first direction with respect to the image forming apparatus, and in which protrusions are formed at both ends in the first direction of the exposure portion, respectively; a housing that holds the photosensitive drum, and has inclined portions formed at both ends in a first direction so as to face the protruding portions, the inclined portions being in contact with the protruding portions so as to be slidable on the protruding portions; a biasing member that presses the exposure section toward the housing; and a first adjusting portion provided on the housing, adjusting a position of the housing in a first direction with respect to the image forming apparatus.

An image forming apparatus according to another embodiment includes: a photosensitive drum; a housing that holds the photosensitive drum and is fixed in position in a first direction with respect to the image forming apparatus, and in which protruding portions are formed at both ends in the first direction of the housing, respectively; an exposure portion facing the photosensitive drum, the exposure portion having inclined portions facing the protrusions formed at both ends in a first direction, the inclined portions being in contact with the protrusions so as to be slidable on the protrusions; a biasing member that presses the exposure section toward the housing; and a first adjusting section provided on the exposing section, the first adjusting section adjusting a position of the exposing section in a first direction with respect to the image forming apparatus.

Through the utility model discloses, can finely tune the distance between exposure portion and the sensitization drum to form the image that the quality is good.

Drawings

FIG. 1 is a schematic view of an image forming apparatus according to the present invention;

FIG. 2 is a schematic view of a partial structure in an image forming apparatus according to the present invention;

FIG. 3 is an enlarged partial cross-sectional view of portion A of FIG. 2;

FIG. 4 is a partially enlarged cross-sectional view of portion B of FIG. 2;

fig. 5 is a partially enlarged perspective view of a portion a in fig. 2;

fig. 6 is a partially enlarged perspective view of a portion B in fig. 2.

Detailed Description

Hereinafter, an image forming apparatus according to an embodiment will be described with reference to the drawings. In the drawings, the same components are denoted by the same reference numerals.

For convenience of explanation, coordinate axes are shown in the drawings. The X-axis direction is a lateral direction (hereinafter also referred to as a horizontal direction) of the image forming apparatus 1. The Y-axis direction is a longitudinal direction (hereinafter also referred to as a vertical direction, second direction) of the image forming apparatus 1. The Z-axis direction is a depth direction (hereinafter also referred to as a first direction) of the image forming apparatus 1. The direction of the image forming apparatus 1 along the X-axis arrow is the right side, the direction of the image forming apparatus 1 along the Y-axis arrow is the upper side, and the direction of the image forming apparatus 1 along the Z-axis arrow (outward in fig. 1) is the front side, i.e., the left side, the lower side, and the rear side, which are opposite to the above. The X-axis direction, the Y-axis direction and the Z-axis direction are orthogonal to each other. In the drawings, the structure is shown enlarged, reduced, or omitted as appropriate for convenience of explanation.

Fig. 1 is a schematic configuration diagram of an image forming apparatus 1 according to the present invention.

As shown in fig. 1, the image forming apparatus 1 of the present embodiment is, for example, a multifunction machine, a printer, a copier, or the like. The image forming apparatus 1 forms an image on a recording medium based on image data read on a document. Next, a case where the image forming apparatus 1 is a multifunction peripheral will be described.

The image forming apparatus 1 has a main body 11, and the main body 11 of the image forming apparatus 1 has a frame 11a (shown in fig. 2) therein, the frame 11a fixing components for image formation inside the image forming apparatus 1. An image reading portion 12 is provided on an upper portion of the main body 11, and the image reading portion 12 is used to read an original to generate image data of the original. The image reading portion 12 is composed of a document conveying portion 13 and a scanner portion 14.

A scanner unit 14 is provided below the document conveying unit 13. The original conveying portion 13 conveys an original to be transferred to the scanner portion 14. The scanner portion 14 has an optical mechanism 15, and the scanner portion 14 reads the original to be transferred conveyed by the original conveying portion 13 or the original to be transferred placed directly on a platen glass of the scanner portion 14 through the optical mechanism 15.

The optical mechanism 15 moves in the lateral direction along the platen glass when reading an image of an original directly placed on the platen glass of the scanner section 14. The optical mechanism 15 reads an original image on one original page line by line. When reading an image of a document conveyed by the document conveying portion 13, the optical mechanism 15 reads the conveyed document at a fixed position shown in fig. 1.

An operation display unit 16 is provided on the front side of the scanner unit 14 and above the main body 11. The operation display unit 16 has a function of receiving an operation by an operator and displaying a state of the image forming apparatus 1. The operation display unit 16 is, for example, a touch panel type liquid crystal display.

The main body 11 has a transfer portion 17 at the center in the longitudinal direction. The main body 11 has a paper feed cassette 18 for feeding a recording medium to the transfer unit 17 at a lower portion. The paper feed cassette 18 accommodates recording media (paper sheets) P of various sizes.

The sheet feeding cassette 18 has a sheet feeding mechanism 19. The paper feed mechanism 19 takes out the recording media P one by one from the paper feed cassette 18 and conveys the recording media P to a conveyance path. For example, the paper feeding mechanism 19 may include a pickup roller, a separation roller, and a paper feeding roller.

The transfer portion 17 forms an image on the recording medium P using toner from the image data read by the scanner portion 14, or image data made by a personal computer or the like.

The transfer portion 17 has a plurality of image forming units 51 that form images using different color toners (e.g., yellow, magenta, cyan, black, etc.), an exposure portion 32, and an intermediate transfer belt 53. The transfer unit 17 converts the image data into color signals of the respective colors, and controls the exposure unit 32 based on the color signals of the respective colors.

The configuration of the transfer section 17 is not limited to this, and the transfer section may have two or three image forming units, or the transfer section may have five or more image forming units.

The image forming units 51 are arranged in parallel below the intermediate transfer belt 53 (in a direction from the left side to the right side in fig. 1).

The exposure section 32 irradiates exposure light to each image forming unit 51. The exposure section 32 may generate a laser scanning beam as exposure light. The exposure section 32 may be configured to include a solid-state scanning element such as a light-emitting diode that generates exposure light.

The structures of the respective image forming units 51 are the same as each other except that the colors of the toners are different. Examples of the toner include a decolorable toner which can be decolored (invisible) by an external stimulus (e.g., temperature, light having a specific wavelength, or pressure), and a normal non-decolorable toner. A toner that is decolored by temperature decolors when it reaches a specific decoloring temperature or higher, and develops color when it is equal to or lower than a specific restoration temperature.

The image forming unit 51 has a photosensitive drum 31 as an image carrier. The photosensitive drum 31 has a photosensitive body (e.g., an organic photoconductor) on an outer circumferential surface. The exposure portion 32 irradiates exposure light to each of the photosensitive drums 31.

Around the photosensitive drum 31, a charger, a developer, a primary transfer roller, a drum cleaner, and the like are arranged.

The exposure section 32 generates exposure light modulated in accordance with image data. The exposure light exposes the surface of the photosensitive drum 31. The potential of the region on the photosensitive drum 31 irradiated with light is changed to form an electrostatic latent image.

The developer develops the electrostatic latent image, and forms a toner image on the surface of the photosensitive drum 31.

The intermediate transfer belt 53 is an endless belt member that circulates, and the intermediate transfer belt 53 is stretched over a driving roller 69 and a plurality of driven rollers 70.

The intermediate transfer belt 53 contacts the photosensitive drum 31 from above. The toner image formed on the photosensitive drum 31 is transferred onto the intermediate transfer belt 53 by applying a primary transfer voltage. After the toner images on the photosensitive drums of the plurality of image forming units are sequentially transferred onto the intermediate transfer belt 53 in such a manner as to overlap each other, toner images formed of the toners of the respective colors are formed.

The secondary transfer roller 71 faces the drive roller 69 across the intermediate transfer belt 53. The contact portion between the intermediate transfer belt 53 and the secondary transfer roller 71 constitutes a secondary transfer position. The driving roller 69 drives the intermediate transfer belt 53 to rotate. When the recording medium P passes through the secondary transfer position, a secondary transfer voltage is applied to the secondary transfer roller 71, and the secondary transfer roller 71 secondarily transfers the toner image on the intermediate transfer belt 53 onto the recording medium P.

A supply section 66 is also disposed above the transfer section 17.

The supply unit 66 includes a plurality of toner cartridges that store toners of different colors, and supplies the toners to the developers of the respective image forming units.

Each toner cartridge is provided with a not-shown marker for detecting the type of toner stored in the image forming apparatus 1. The identification portion includes at least information of a color of toner of the toner cartridge and information identifying whether the toner is normal toner or achromatic toner.

As shown in fig. 1, a belt cleaner 72 is disposed at a position facing one of the driven rollers 70 across the intermediate transfer belt 53. The belt cleaner 72 removes the residual transfer toner on the intermediate transfer belt 53 from the intermediate transfer belt 53. Specifically, the belt cleaner 72 may be a resin member made of urethane or the like.

A conveying path from the paper feed cassette 18 to the secondary transfer roller 71 is provided with a pair of conveying rollers 75 and a pair of registration rollers 76. The pair of transport rollers 75 transport the recording medium P taken out of the paper feed cassette 18 by the paper feed mechanism 19.

The pair of registration rollers 76 align the positions of the leading ends of the recording medium P fed from the pair of transport rollers 75 at the positions where they abut against each other. The positions of the pair of registration rollers 76 in contact with each other constitute registration positions. The pair of registration rollers 76 conveys the recording medium P such that the leading end of the region on the recording medium P to which the toner image is to be transferred reaches the secondary transfer position when the leading end of the toner image reaches the secondary transfer position.

A fixing portion 81 is disposed downstream (upper side in fig. 1) of the secondary transfer roller 71 in the conveying direction of the recording medium P. The fixing unit 81 heats and pressurizes the recording medium P to fix the toner image to the recording medium P.

The discharge roller pair 21 is disposed downstream (upper left side in fig. 1) of the fixing section 81 in the conveying direction of the recording medium P. The discharge roller pair 21 discharges the recording medium P to the sheet discharge portion 22.

The reverse conveyance path 10 is disposed downstream (right side in fig. 1) of the fixing section 81 in the conveyance direction of the recording medium P. The reverse conveyance path 10 reverses the recording medium P and guides the recording medium P to the secondary transfer roller 71. The reverse conveyance path 10 is used when performing duplex printing.

Next, the structure of the photosensitive drum 31, the exposure section 32, and the periphery thereof in the image forming apparatus 1 will be described with reference to fig. 2.

Fig. 2 is a schematic diagram showing a partial configuration of the photosensitive drum 31, the exposure unit 32, and the periphery thereof in the image forming apparatus 1 according to the present invention.

As shown in fig. 2, the image forming apparatus 1 includes a photosensitive drum 31, an exposure unit 32, a housing 33, and an urging member 34.

The photosensitive drum 31 in the image forming apparatus 1 is formed in a cylindrical shape with its axis extending in the first direction, that is, the photosensitive drum 31 is formed to extend in the first direction, and the photosensitive drum 31 has a photosensitive body on its outer surface. The exposure section 32 is a line-type exposure apparatus, the exposure section 32 is provided on the lower side of the photosensitive drum 31 in the second direction, that is, the exposure section 32 is provided opposite to the photosensitive drum 31 in the second direction, and the exposure section 32 forms an electrostatic latent image on the photosensitive drum 31 by irradiating the photosensitive drum 31 with exposure light.

The housing 33 is used for holding the photosensitive drum 31 so that the photosensitive drum 31 can rotate about its own axis, the housing 33 is provided on the frame 11a of the image forming apparatus 1, and the housing 33 is fixedly held by the frame 11a in the second direction, that is, the position of the housing 33 is fixed in the second direction with respect to the image forming apparatus 1 (i.e., the frame 11 a). An opening is formed in the casing 33 on the side facing the exposure portion 32 so that there is no obstruction between the photosensitive drum 31 and the exposure portion 32, and the photosensitive drum 31 is irradiated with exposure light from the exposure portion 32 through the opening.

The lower surface of the exposure section 32 in the second direction is further provided with an urging member 34 which abuts against the lower surface, and the urging member 34 applies a force to move the exposure section 32 toward the housing 33 which holds the photosensitive drum 31, that is, the urging member 34 presses the exposure section 32 toward the housing 33 in the second direction, and the exposure section 32 is pressed by the urging member 34 in the second direction and abuts against the housing 33. Specific examples of the urging member 34 include a spring, elastic rubber, and the like. For example, the biasing member 34 is a spring having one end fixed inside the image forming apparatus 1 and the other end connected to the exposure unit 32. The distance between the exposure portion 32 and the photosensitive drum 31 is determined by the elastic force of the urging member 34, and the distance between the exposure portion 32 and the photosensitive drum 31 is made to meet the requirements for image formation by appropriately selecting the elastic force of the urging member 34.

Since the image forming apparatus 1 tends to be miniaturized, when the image forming apparatus 1 is constructed using a compact system in which the distance between the exposure section 32 and the photosensitive drum 31 is short, the exposure section 32 and the photosensitive drum 31 are compact in position, and accurate positioning is not easily performed at the time of mounting, resulting in a phenomenon in which the focal distance does not coincide with a prescribed distance, thereby causing deterioration in image formation. Further, since the elastic force of the urging member 34 is a fixed value, if the distance between the exposure section 32 and the photosensitive drum 31 slightly varies due to vibration or the like, if the distance between the photosensitive drum 31 and the exposure section 32 cannot be adjusted, the quality of image formation is affected by a deviation in the focal distance.

Next, an embodiment of the first invention in which the distance between the exposure section 32 and the photosensitive drum 31 can be adjusted will be described exemplarily with reference to fig. 2 to 6.

Fig. 3 is a partially enlarged cross-sectional view of a portion a in fig. 2.

Fig. 4 is a partially enlarged cross-sectional view of part B in fig. 2.

Fig. 5 is a partially enlarged perspective view of a portion a in fig. 2.

Fig. 6 is a partially enlarged perspective view of a portion B in fig. 2.

In fig. 5 and 6, the exposure portion is not shown in order to clearly show a part of the structure.

In the present embodiment, as shown in fig. 2, the exposure section 32 is fixed in position in the first direction with respect to the image forming apparatus 1 (i.e., the frame 11a), that is, the exposure section 32 is fixed in the first direction with respect to the image forming apparatus 1. The position of the exposure section 32 in the second direction with respect to the image forming apparatus 1 (i.e., the frame 11a) can be changed, and the urging member 34 presses the exposure section 32 against the housing 33 of the photosensitive drum 31 in the second direction.

Specifically, the exposure unit 32 may be fixed in the first direction with respect to the image forming apparatus 1 by inserting a positioning shaft 39 in the exposure unit 32 in the second direction, the positioning shaft 39 being fixedly provided in the image forming apparatus 1, and the positioning shaft 39 blocking the exposure unit 32 when the exposure unit 32 tends to move in the first direction, that is, restricting the movement of the exposure unit 32 in the first direction.

In the present embodiment, the position of the housing 33 in the first direction with respect to the image forming apparatus 1 and the exposure section 32 is adjustable. Specifically, as shown in fig. 2 and 4, one of both end portions of the housing 33 in the first direction near the front side is formed with a convex wall portion 40 that protrudes upward. The image forming apparatus 1 further includes a first adjusting portion 35, the first adjusting portion 35 being provided on the housing 33, specifically, the first adjusting portion 35 being provided on the housing 33 so as to penetrate a protruding wall portion 40 formed on the housing 33, the first adjusting portion 35 adjusting a position of the housing 33 in the first direction with respect to the image forming apparatus 1 and the exposure portion 32.

In the present embodiment, a set screw is exemplarily described as a specific embodiment of the first adjustment portion 35.

As shown in fig. 2 and 4, a set screw as the first adjustment portion 35 is provided in the first direction, one end of the set screw abuts against the frame 11a, and the set screw penetrates through a convex wall portion 40 formed on the housing 33 in the first direction and is screwed to the convex wall portion 40.

Since the set screw is screwed to the housing 33, by rotating the other end of the set screw opposite to the one end abutting on the frame 11a, the housing 33 can be moved to the front side or the rear side in accordance with the screwing direction of the screw, that is, moved in the first direction with respect to the frame 11a, and since the exposure section 32 is fixed in the first direction with respect to the image forming apparatus 1 (that is, the frame 11a), the housing 33 is also moved in the first direction with respect to the exposure section 32. The specific movement amount can be set according to requirements by the parameters of the threads.

The first adjustment unit is described by way of example only, and is not limited to this, and any configuration may be used that can adjust the position of the housing 33 in the first direction with respect to the image forming apparatus 1 and the exposure unit 32, and may be, for example, a jack screw, a positioning bolt, or another configuration.

As shown in fig. 2, the exposed portion 32 has projections 36 formed at both ends in the first direction. Specifically, as shown in fig. 3, one protruding portion 36 is formed on one of both end portions of the exposure portion 32 in the first direction. As shown in fig. 4, another protruding portion 36 is formed on the other of the two ends of the exposure portion 32 in the first direction. The two protruding portions 36 protrude toward the housing 33 of the photosensitive drum 31.

As shown in fig. 2, inclined portions 37 opposed to the protruding portions 36 are formed at both end portions in the first direction of the housing 33 holding the photosensitive drum 31, respectively. The inclined portion 37 is in contact with the protrusion portion 36 so as to be slidable on the protrusion portion 36. Specifically, as shown in fig. 3, one inclined portion 37 opposed to one of the projecting portions 36 is formed on one of both end portions of the housing 33 in the first direction, and the inclined portion 37 is in contact with the projecting portion 36 in a manner slidable on the projecting portion 36. As shown in fig. 4, another inclined portion 37 is formed at the other of the two ends of the housing 33 in the first direction so as to face the other projection portion 36, and the inclined portion 37 is in contact with the projection portion 36 so as to be slidable on the projection portion 36.

The two inclined portions 37 are formed so as to have the same inclination direction, and for example, both the two inclined portions 37 are formed so as to be inclined closer to the exposure portion 32 toward the front side (direction in which the Z axis is directed) of the housing 33 in the image forming apparatus 1 in the first direction.

However, the present invention is not limited to this, and the two inclined portions 37 may be formed to be inclined in the direction opposite to the above-described direction, or the inclined portions 37 may be formed in a step shape having a step difference, or the like.

Hereinafter, a method of adjusting the focal distance between the exposure unit 32 and the photosensitive drum 31 will be described.

As shown in fig. 3 and 4, as described above, the exposure unit 32 is fixed to the image forming apparatus 1 in the first direction, the exposure unit 32 is movable in the second direction with respect to the image forming apparatus 1, and is pressed by the urging member 34, the housing 33 is movable in the first direction with respect to the image forming apparatus 1 and the exposure unit 32, and the position of the housing 33 is fixed in the second direction with respect to the image forming apparatus 1.

The exposure section 32 is urged by the urging member 34 to abut on the outer side surface of the housing 33, whereby the two projections 36 of the exposure section 32 abut on the two inclined portions 37 of the housing 33, respectively, by the urging force of the urging member 34. When the housing 33 is not moved in the first direction relative to the image forming apparatus 1, the focal distance between the exposure portion 32 and the photosensitive drum 31 is kept fixed.

When it is necessary to finely adjust the focal distance between the exposure section 32 and the photosensitive drum 31, for example, when it is necessary to increase the focal distance between the exposure section 32 and the photosensitive drum 31, the first adjustment section 35 is operated to move the housing 33 rearward in the first direction with respect to the image forming apparatus 1 and the exposure section 32, and at this time, since the projection sections 36 at both ends of the exposure section 32 are constantly pressed by the urging member 34 and abut against the inclined sections 37 at both ends of the housing 33, when the housing 33 is moved, the inclined sections 37 at both ends slide along the projection sections 36 at both ends, and the contact position between the projection sections 36 and the inclined sections 37 is changed, the inclined sections 37 press the projection sections 36, and the projection sections 36 are moved downward in the second direction against the force of the urging member 34. That is, the focal distance between the exposure section 32 and the photosensitive drum 31 is increased.

Thereby, adjustment of the distance in the second direction between the exposure section 32 and the photosensitive drum 31 is achieved by the movement of the housing 33 in the first direction. When it is necessary to reduce the focal distance between the exposure section 32 and the photosensitive drum 31, the housing 33 may be moved to the front side with respect to the image forming apparatus 1 and the exposure section 32, in contrast to the above operation.

The position of the projection 36 formed on the exposure section 32 in the first direction may be arbitrarily set according to circumstances, and it is preferable that the projection is formed at a position facing the urging member 34 on the surface of the exposure section 32 contacting the urging member 34 through the exposure section 32, so that the displacement of the urging member 34 and the projection 36 in the first direction is minimized, and the deflection of the exposure section 32 due to uneven force applied to both surfaces is avoided.

In addition, in a preferred embodiment, the protrusion 36 is formed in a hemispherical shape, so that relative movement between the inclined portion 37 and the protrusion 36 can be made smooth, and the adjustment accuracy can be further improved.

With the above-described embodiment, the projection portions are provided at both ends of the exposure portion in the first direction, the inclined portions opposite to the projection portions are provided at both ends of the housing in the first direction, and the position of the housing in the first direction is adjusted by the first adjustment portion, so that fine adjustment of the focal distance between the exposure portion and the photosensitive drum can be realized, and the problem of mismatch of the focal distance between the photosensitive drum and the exposure portion can be avoided by adjusting the focal distance even in different types of image forming apparatuses. Even in a miniaturized image forming apparatus, when the distance between the exposure unit and the photosensitive drum varies, the focal length can be adjusted, and deterioration of image quality can be prevented to form an image with good quality.

In addition, in the present embodiment, it is preferable that the distance (distance in the second direction) between one of the two ends of the housing 33 in the first direction and the exposure portion 32 can be adjusted independently.

As shown in fig. 2, 4, and 6, the housing 33 is provided with a second adjustment portion 38. The second regulating portion 38 is regulated in the same manner as the first regulating portion 35, and the second regulating portion 38 individually regulates the position of one of the inclined portions 37 in the first direction with respect to the housing 33. One of the two inclined portions 37 is formed integrally with the housing 33, and the other is a separate member. Specifically, as shown in fig. 5, the position of the inclined portion 37 formed integrally with the housing 33 is fixed with respect to the housing 33. As shown in fig. 6, the housing 33 is formed with a groove portion 41 provided with the inclined portion 37 as a separate member, and the groove portion 41 leaves only a space allowing a certain movement of the inclined portion 37 as a separate member in the first direction with respect to the housing 33. That is, when the inclined portion 37 as the independent member is provided in the groove portion 41, both ends in the first direction of the groove portion 41 leave certain moving spaces from both ends in the first direction of the inclined portion 37 as the independent member, and the inclined portion 37 as the independent member has no moving space in the horizontal direction (X-axis direction).

As a specific embodiment, a set screw is exemplarily described as one specific embodiment of the second adjustment portion 38. The set screw is connected to the housing 33 so as to pass through the groove portion 41 of the housing 33, and the set screw as the second adjusting portion 38 is rotatable only about its axis in the housing 33 and fixed in position relative to the housing 33 in other directions. The inclined portion 37 as a separate member is provided in the recessed groove portion 41 so as to be penetrated by a set screw. The inclined portion 37 as a separate member is screwed with a set screw.

Since the set screw is screwed with the inclined portion 37 as a separate member and the space in the groove portion 41 does not allow the inclined portion 37 as a separate member to rotate with the set screw, by rotating the set screw, the inclined portion 37 as a separate member can only move toward the front side or the rear side in accordance with the screwing direction of the screw, that is, in the first direction with respect to the housing 33, that is, the position of the inclined portion 37 as a separate member in the first direction with respect to the housing 33 is adjusted by the second adjusting portion 38. Since the exposure section 32 is fixed in the first direction with respect to the image forming apparatus 1 (i.e., the frame 11a), the inclined section 37 as an independent member also moves in the first direction with respect to the exposure section 32. The specific movement amount can be set according to requirements by the parameters of the threads.

When it is necessary to individually adjust the distance (distance in the second direction) between one of the two ends of the housing 33 in the first direction and the exposure section 32, the inclined section 37 as an independent member is moved in the first direction with respect to the housing 33 by rotating the second adjustment section 38 as in the first adjustment section 35, whereby the inclined section 37 as an independent member presses the corresponding protrusion section 36 to move it in the second direction.

Thus, the distance in the second direction between one of the two ends of the housing 33 in the first direction and the exposure portion 32 is adjusted independently by moving the inclined portion 37 as an independent member in the first direction relative to the housing 33, so that the angle between the exposure portion 32 and the photosensitive drum 31 is adjusted, and a phenomenon that the exposure portion 32 and the photosensitive drum 31 cannot be adjusted when they are deflected to cause a malfunction is avoided.

The second adjustment unit is described by way of example only, and is not limited to this, and any configuration may be used that can adjust the position of the inclined portion 37 as an independent member in the first direction with respect to the housing 33 and the exposure unit 32, and may be, for example, a jack screw, a positioning bolt, or another configuration.

In the following, a second embodiment of the present invention, in which the distance between the exposure section and the photosensitive drum can be adjusted, will be briefly described, differently from the first embodiment. In addition, the same parts as those in the above embodiments are not described again, and only different parts will be described.

In the present embodiment, the position of the exposure unit in the first direction with respect to the image forming apparatus and the housing is adjusted by changing the manner in which the first adjustment unit is provided in the housing in the above-described embodiment to the manner in which the first adjustment unit is provided in the exposure unit, and the positioning shaft that restricts the position of the exposure unit in the first direction is not provided, that is, the first adjustment unit adjusts the position of the exposure unit in the first direction with respect to the image forming apparatus and the housing in the present embodiment. Similarly, any structure that can adjust the position of the exposure portion in the first direction with respect to the image forming apparatus or the housing may be used, and examples of the structure may include a set screw, a jack screw, a set bolt, and other structures. In addition, unlike the first embodiment, the position of the housing in the first direction with respect to the image forming apparatus is fixed, and specifically, the movement of the housing in the first direction is restricted in the same manner as the movement of the exposure section in the first direction in the above-described embodiment, that is, the movement is restricted by the positioning shaft. This is achieved in that the exposure section is moved in the first direction relative to the housing by the first adjustment section.

Further, it is different from the case of the first embodiment in that the inclined portion is formed and the projection portion is formed in the exposure portion. In the present embodiment, the case has protrusions formed at both ends in the first direction. The two protrusions protrude in a direction approaching the exposure portion. Inclined portions facing the protruding portions are formed at both ends of the exposure portion in the first direction. The inclined portion is in slidable contact with the protrusion portion. Also, as a preferred embodiment, the protrusion is formed in a hemispherical shape.

Thus, the distance between the exposure portion and the photosensitive drum in the second direction is adjusted by moving the exposure portion in the first direction by the first adjustment portion, as in the principle of the first embodiment.

In addition, in the present embodiment, it is preferable that the distance (distance in the second direction) between one of the two ends of the exposure section in the first direction and the housing be adjusted independently.

Unlike the first embodiment in which the second adjustment portion is provided in the housing, the present embodiment is provided with the second adjustment portion in the exposure portion. One of the two inclined portions on the exposure section is formed integrally with the exposure section and is fixed in position relative to the exposure section, and the other is an independent member and is adjusted in position in the first direction relative to the exposure section by the second adjustment section.

The inclined portion as an independent member is moved in the first direction with respect to the exposure portion by operating the second adjustment portion, whereby the inclined portion as an independent member presses the corresponding protrusion portion to move in the second direction.

The individual adjustment of the distance in the second direction between one of the two ends of the exposure section in the first direction and the housing is achieved by the movement of the inclined section as an independent member in the first direction relative to the exposure section.

Similarly, any structure that can adjust the position of the inclined portion as an independent member in the first direction with respect to the housing and the exposure portion may be used, and examples thereof include a set screw, a jack screw, a set bolt, and other structures.

According to at least one embodiment described above, fine adjustment of the focal distance between the exposure section and the photosensitive drum can be achieved, and the problem of the mismatch of the focal distance between the photosensitive drum and the exposure section can be avoided by adjusting the focal distance even in different types of image forming apparatuses. Even in a miniaturized image forming apparatus, when the distance between the exposure unit and the photosensitive drum varies, the focal length can be adjusted, and deterioration of image quality can be prevented to form an image with good quality.

While several embodiments of the present invention have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the invention. These new embodiments can be implemented in other various manners, and various omissions, substitutions, combinations, and changes can be made without departing from the gist of the present invention. These embodiments and modifications are included in the scope and gist of the present invention, and are included in the present invention described in the claims and the equivalent scope thereof.

Claims (10)

1. An image forming apparatus, comprising:

a photosensitive drum;

an exposure portion that faces the photosensitive drum and is fixed in position in a first direction with respect to the image forming apparatus, and in which protrusions are formed at both ends in the first direction of the exposure portion, respectively;

a housing that holds the photosensitive drum, and has inclined portions formed at both ends in a first direction so as to face the protruding portions, the inclined portions being in contact with the protruding portions so as to be slidable on the protruding portions;

a biasing member that presses the exposure section toward the housing; and

a first adjustment portion provided on the housing, which adjusts a position of the housing in a first direction with respect to the image forming apparatus.

2. The image forming apparatus according to claim 1,

a second regulating portion is provided on the housing, and one of the inclined portions is fixed in position with respect to the housing, and the other of the inclined portions is regulated in position in the first direction with respect to the housing by the second regulating portion.

3. The image forming apparatus according to claim 2,

the first adjusting part and the second adjusting part are set screws.

4. The image forming apparatus according to claim 3,

the protrusion is formed in a hemispherical shape.

5. The image forming apparatus according to claim 4,

the force application component is a spring.

6. An image forming apparatus, comprising:

a photosensitive drum;

a housing that holds the photosensitive drum and is fixed in position in a first direction with respect to the image forming apparatus, and in which protruding portions are formed at both ends in the first direction of the housing, respectively;

an exposure portion facing the photosensitive drum, the exposure portion having inclined portions facing the protrusions formed at both ends in a first direction, the inclined portions being in contact with the protrusions so as to be slidable on the protrusions;

a biasing member that presses the exposure section toward the housing; and

and a first adjusting section provided on the exposing section, the first adjusting section adjusting a position of the exposing section in a first direction with respect to the image forming apparatus.

7. The image forming apparatus according to claim 6,

a second adjustment portion is provided on the exposure portion, one of the inclination portions is fixed in position with respect to the exposure portion, and the other of the inclination portions is adjusted in position in the first direction with respect to the exposure portion by the second adjustment portion.

8. The image forming apparatus according to claim 7,

the first adjusting part and the second adjusting part are set screws.

9. The image forming apparatus according to claim 8,

the protrusion is formed in a hemispherical shape.

10. The image forming apparatus according to claim 9,

the force application component is a spring.

Images