JP2011099908A - Optical device, optical scanner, and image-forming device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To keep a relative positional relation between a datum, which positions an optical member, and a spring member, which holds the optical member, compared with a case in which this composition is not used. <P>SOLUTION: A relation between the sizes x1 in the longitudinal direction of a reflection mirror of datums 116A, 116B, and the size x2 in width of a lengthwise hole part 120 is set to a tolerance which makes the datums 116A, 116B firmly fitted to the lengthwise hole part 120. Consequently, when a leaf spring member 118 is accommodated in a groove part 100A, the leaf spring member 118 is surely (strictly) positioned to the longitudinal direction of a reflection mirror 112M. Furthermore, the bending direction of a pressing part 126 is made to orthogonally cross the longitudinal direction of the reflection mirror 112M. In this case, even if a degree of the bend varies, a pressing position does not change in the longitudinal direction of the reflection mirror 112M. In other words, the relative positional relation between the datums 116A, 116B and the pressing position of the pressing part 126 does not collapse, and consequently the deflection amount of the reflection mirror 112M does not vary. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an optical device, an optical scanning device, and an image forming apparatus.

  In Patent Document 1, a holding member functioning as a leaf spring formed by bending a metal plate is attached to each of holes provided in a pair of movable carriages, and sandwiched between the pair of holding members. It is described that both ends of the scanning light reflecting mirror are inserted and the scanning light reflecting mirror is held by an elastic force.

  In this cited document 1, when attaching the holding member to the carriage, the longitudinal direction of the scanning light reflecting mirror of the holding member is performed by abutting the flange formed on the holding member against the peripheral edge of the hole provided in the carriage. Yes.

  Further, the holding member bends a part of the holding member in a substantially U shape parallel to the longitudinal direction of the scanning light reflecting mirror, makes line contact with the scanning light reflecting mirror, and presses and holds the scanning light reflecting mirror. Like to do.

JP-A-9-321194

  The present invention provides an optical device, an optical scanning device, and an optical device capable of maintaining the relative positional relationship between a positioning portion that positions an optical member and a spring member that holds the optical member, as compared with a case without this configuration. An object is to obtain an image forming apparatus.

  According to the first aspect of the present invention, a rectangular optical member that deflects incident light, and both longitudinal ends of the optical member are spanned, and a width direction intersecting the longitudinal direction of the optical member, the longitudinal direction And the attachment part in which the positioning part for performing each positioning of the thickness direction which intersects both of the width directions is formed, and the longitudinal direction is positioned with respect to the attachment part using the positioning part, And a spring member provided with a holding portion that presses and holds the optical member with an elastic force in the thickness direction.

  According to a second aspect of the present invention, in the first aspect of the present invention, the rotation direction of the spring member with the thickness direction as the rotation center is positioned by the positioning portion.

According to a third aspect of the present invention, in the first or second aspect of the present invention, the holding portion has a leaf spring shape bent along the width direction, and faces the optical member. A spherical projection is formed.
A fourth aspect of the present invention is the datum according to any one of the first to third aspects, wherein the positioning portion protrudes in a block shape, and the optical member is projected by a protruding front end surface of the datum. Is positioned, and the spring member is positioned by the side surface of the datum.

  The invention according to claim 5 is the invention according to claim 4, wherein the optical member is sandwiched and held between the datum and the holding portion of the spring member, and is within the range of the protruding tip surface of the datum. The pressing point of the holding portion is positioned so as to face the surface.

  According to the sixth aspect of the present invention, when light is scanned in one direction by a scanning mechanism, a longitudinal dimension is set in accordance with the scanning width, and the optical member that deflects the scanned light, and the optical Positioning portions for positioning in the width direction intersecting the longitudinal direction of the optical member, and in the thickness direction intersecting both the longitudinal direction and the width direction are respectively spanned at both longitudinal ends of the member. A spring provided with a formed mounting portion and a holding portion that is positioned in the longitudinal direction with respect to the mounting portion using the positioning portion and presses and holds the optical member with an elastic force in the thickness direction. And a member.

  According to a seventh aspect of the present invention, in the invention of the sixth aspect, the spring member is positioned by the positioning portion in a rotational direction centered on the longitudinal direction and the thickness direction.

  The invention according to claim 8 is the invention according to claim 6 or claim 7, wherein the holding portion is a leaf spring shape bent along the width direction, and is a spherical surface facing the optical member. Shaped protrusions are formed.

  A ninth aspect of the present invention is the datum according to any one of the sixth to eighth aspects, wherein the positioning portion projects in a block shape, and the optical member is projected by a projecting tip surface of the datum. Is positioned, and the spring member is positioned by the side surface of the datum.

  According to a tenth aspect of the present invention, in the invention according to the ninth aspect, the optical member is held between the datum and the holding portion of the spring member, and is within the range of the protruding front end surface of the datum. The pressing point of the holding portion is positioned so as to face the surface.

  According to an eleventh aspect of the present invention, an electrostatic latent image is formed on an image carrier using the optical scanning device according to any one of the sixth to tenth aspects and the optical scanning. An image forming unit that develops and transfers an image onto a recording sheet.

  According to the first, sixth, and eleventh aspects, the relative positional relationship between the positioning portion that positions the optical member and the spring member that holds the optical member is maintained as compared with the case where the present configuration is not provided. be able to.

  According to invention of Claim 2, 7, the attitude | position of a spring member can be stabilized.

  According to invention of Claim 3, 8, the press position of the optical member with respect to datum can be stabilized.

  According to invention of Claim 4, 9, a spring member can be arrange | positioned between a mirror and a housing attachment space, and it can reduce in size.

  According to the fifth and tenth aspects of the present invention, it is possible to reduce factors that cause the optical member to bend in the longitudinal direction as compared with the case where the present configuration is not provided.

1 is a perspective view showing an image forming apparatus according to an embodiment of the present invention. It is sectional drawing which shows the image forming apparatus shown in FIG. FIG. 2 is a side view illustrating a state in which a main opening / closing portion and an intermediate transfer belt unit are opened and closed with respect to a main body of the image forming apparatus illustrated in FIG. 1 and a state in which an image forming unit is attached to and detached from the main body. It is a perspective view of the optical scanning device concerning this embodiment. It is a side view of the optical scanning device concerning this embodiment. It is a top view of the optical scanning device concerning this embodiment. FIG. 6 is an exploded perspective view showing a holding structure for a reflecting mirror spanned between side walls of an optical scanning device according to the present embodiment. It is the VIII-VIII sectional view taken on the line of FIG. FIG. 9 is an exploded perspective view showing a holding structure of a reflection mirror spanned between side walls of an optical scanning device according to Modification 1; FIG. 10 is a sectional view taken along line XX in FIG. 9. FIG. 14 is an exploded perspective view showing a holding structure for a reflection mirror spanned between side walls of an optical scanning device according to Modification 2. It is the XII-XII sectional view taken on the line of FIG.

(Overall configuration of image forming apparatus)
1 and 2 show an image forming apparatus 10 according to an embodiment of the present invention.

  As shown in FIGS. 1 and 2, the image forming apparatus 10 includes an image forming apparatus main body 12, and the image forming apparatus main body 12 includes a front opening / closing portion 18 so as to be openable / closable with respect to the exterior cover 14. The main opening / closing part 20 is mounted.

  The front opening / closing part 18 opens and closes with respect to the image forming apparatus main body 12 so as to rotate about the central axis 24. An operation unit 34 is attached to the front opening / closing unit 18. The operation unit 34 includes, for example, a numeric keypad for inputting the number of recording media on which image formation is performed, a start button that is operated when image formation is started, and the like.

  Further, a supply opening / closing part 30 is attached to the front opening / closing part 18 so as to open / close with respect to the front opening / closing part 18. The supply opening / closing part 30 is normally closed with respect to the front opening / closing part 18 as shown in FIGS. 1 and 2. When a recording medium different from a recording medium stored in a recording medium supply device 510 described later is used, the supply opening / closing part 30 is opened with respect to the front opening / closing part 18.

  The main opening / closing part 20 opens and closes with respect to the image forming apparatus main body 12 so as to rotate about the central axis 26. The main opening / closing unit 20 is normally closed with respect to the image forming apparatus main body 12 and is opened when the image forming units 200Y, 200M, 200C, and 200K are attached to and detached from the image forming apparatus main body 12.

  Further, the front opening / closing part 18 is attached to the main opening / closing part 20, and prior to opening the main opening / closing part 20 in order to prevent the support roll 70, the intermediate transfer belt 62 and the like from interfering with the front opening / closing part 18. be opened. When closing the front opening / closing part 18 with respect to the image forming apparatus main body 12, the main opening / closing part 20 is closed with respect to the image forming apparatus main body 12 prior to closing the front opening / closing part 18.

  The main opening / closing part 20 is attached with a sub opening / closing part 32 so as to open / close with respect to the main opening / closing part 20. The sub opening / closing unit 32 can be opened / closed independently of the main opening / closing unit 20, and the main opening / closing unit 20 is closed with respect to the image forming apparatus main body 12 and is open with respect to the main opening / closing unit 20. can do. The sub opening / closing unit 32 is opened when all or part of the cleaning device 96 is attached to or detached from the image forming apparatus main body 12. Further, the upper surface of the sub opening / closing part 32 is used as a discharge part for discharging a recording medium on which an image is formed.

  In the image forming apparatus main body 12, an image forming unit 40 for forming an image on a recording medium is provided. The image forming unit 40 includes, for example, four image forming units 200Y, 200M, 200C, and 200K.

  Each of the image forming units 200Y, 200M, 200C, and 200K is used as an image forming structure, and each includes a photosensitive drum 210Y, 210M, 210C, and 210K, and each is attached to and detached from the image forming apparatus main body 12. can do. The image forming units 200Y, 200M, 200C, and 200K are arranged in the order of the image forming units 200Y, 200M, 200C, and 200K from the rear side (the right side in FIG. 2) of the image forming apparatus main body 12.

  Each of the photosensitive drums 210Y, 210M, 210C, and 210K is used as an image holding body that holds an image.

  Further, the image forming unit 40 includes an optical scanning device 41. The optical scanning device 41 applies light to each of the photosensitive drums 210Y, 210M, 210C, and 210K (exposure light LY, LM, LC, LK / hereinafter sometimes referred to as “exposure light L”). Irradiation forms latent images on the surfaces of the photosensitive drums 210Y, 210M, 210C, and 210K.

  The image forming unit 40 includes developing devices 46Y, 46M, 46C, and 46K. The developing device 46Y develops the latent image formed on the photosensitive drum 210Y using yellow toner stored therein. The developing device 46M develops the latent image formed on the photosensitive drum 210M using magenta toner stored therein. The developing device 46C develops the latent image formed on the photosensitive drum 210C using cyan toner stored therein. The developing device 46K develops the latent image formed on the photosensitive drum 210K using black toner stored therein.

  The image forming unit 40 includes a transfer device 58. The transfer device 58 includes an intermediate transfer belt unit 60 and a secondary transfer device 84. The intermediate transfer belt unit 60 includes an intermediate transfer belt 62.

  The intermediate transfer belt 62 is at least one of an image (toner image) transferred from the photosensitive drums 210Y, 210M, 210C, and 210K and a recording medium (paper) onto which the image is transferred from the photosensitive drums 210Y, 210M, 210C, and 210K. It is used as a conveying member that conveys. Further, the intermediate transfer belt 62 is endless, and is stretched around the support rolls 64, 66, 68, 70, 72 so as to be able to rotate in the direction indicated by the arrow in FIG.

  In addition, the intermediate transfer belt unit 60 includes primary transfer rolls 80Y, 80M, 80C, and 80K that are used as a primary transfer device. The primary transfer rolls 80Y, 80M, 80C, and 80K are provided with a yellow toner image, a magenta toner image, a cyan toner image, and a black toner image respectively formed on the surfaces of the photosensitive drums 210Y, 210M, 210C, and 210K. Then, the image is transferred to the intermediate transfer belt 62.

  The secondary transfer device 84 has a secondary transfer roll 86. The secondary transfer roll 86 further transfers the yellow toner image, magenta toner image, cyan toner image, and black toner image transferred to the intermediate transfer belt 62 to the recording medium.

  Further, the transfer device 58 has a cleaning device 96, and the cleaning device 96 has a scraping member 98. The scraping member 98 scrapes off the toner of each color remaining on the surface of the intermediate transfer belt 62 after the toner image of each color is transferred to the recording medium by the secondary transfer roll 86. In the main body of the cleaning device 96, the toner scraped off by the scraping member 98 is collected. The cleaning device 96 can be attached to and detached from the image forming apparatus main body 12 through an opening formed by opening the sub opening / closing portion 32.

  Of the members constituting the transfer device 58, the intermediate transfer belt unit 60 and the cleaning device 96 are mounted on the main opening / closing portion 20 side. Of the transfer device 58, the secondary transfer roll 86 is mounted on the image forming apparatus main body 12 side.

  In the image forming apparatus main body 12, a fixing device 50 is provided for fixing the toner image transferred to the recording medium by the secondary transfer roll 86 to the recording medium.

  A collection container 260 is provided in the image forming apparatus main body 12. In the collection container 260, excess developer discharged from the developing devices 46Y, 46M, 46C, and 46K is collected. The collection container 260 is integrated with the image forming unit 200K, for example.

  A recording medium supply device 510 that supplies a recording medium to the image forming unit 40 is mounted in the image forming apparatus main body 12. The recording medium supply device 510 can be pulled out to the front side (left side in FIG. 2) of the image forming apparatus main body 12, and the recording medium can be loaded with the recording medium supply apparatus 510 pulled out from the image forming apparatus main body 12. To be replenished.

  The recording medium supply device 510 includes a recording medium storage container 512 that stores recording media such as plain paper in a stacked state. In addition, the recording medium supply device 510 includes a transport roll 514 that extracts the uppermost recording medium stored in the recording medium storage container 512 and transports the extracted recording medium toward the image forming unit 40. The recording medium supply device 510 has a retard roll 516 that is used to roll over the recording medium and prevent a plurality of recording media from being conveyed to the image forming unit 40 in an overlapping state.

  Further, a conveyance path 530 used for conveying the recording medium is formed in the image forming apparatus main body 12. The conveyance path 530 includes a main conveyance path 532, a reverse conveyance path 534, and a sub conveyance path 536.

  The main conveyance path 532 is used for conveying the recording medium supplied from the recording medium supply device 510 to the image forming unit 40 and discharging the recording medium on which the image is formed to the outside of the image forming apparatus main body 12. In order from the upstream side in the direction in which the recording medium is transported along the main transport path 532, the transport roll 514, the retard roll 516, the resist roll 542, the secondary transfer roll 86, the fixing device 50, and the discharge are sequentially discharged. A roll 544 is disposed.

  The registration roll 542 temporarily stops the leading end of the recording medium conveyed from the recording medium supply device 510 side, and causes the recording medium to match the timing at which each color toner image is transferred to the intermediate transfer belt 62. It sends out toward the secondary transfer roll 86.

  The discharge roll 544 discharges the recording medium on which the toner of each color is fixed by the fixing device 50 to the outside of the image forming apparatus main body 12.

  The reverse conveyance path 534 is a conveyance path that is used for reversing and supplying the recording medium having the toner image fixed on one surface thereof to the image forming unit 40. For example, two reverse transfer rolls 548 and 548 are arranged along the reverse transfer path 534. A recording medium is supplied to the reverse conveyance path 534 from the rear end side by rotating the discharge roll 544 in a reverse direction with the rear end of the recording medium interposed therebetween, and the supplied recording medium is supplied to the reverse conveyance roll 548. By 548, the sheet is conveyed to a position upstream of the registration roll 542.

  The sub-transport path 536 is a transport path for supplying a recording medium different from the recording medium stored in the recording medium supply apparatus 510 to the image forming unit 40. A recording medium is supplied to the sub-transport path 536 from the front side of the image forming apparatus main body 12 with the supply opening / closing part 30 opened. A transport roll 552 and a retard roll 554 are provided along the sub-transport path 536. The transport roll 552 is supplied to the sub transport path 536 and transports the recording medium toward the image forming unit 40. The retard roll 554 is used to roll the recording medium supplied to the sub-conveying path 536 and prevent the recording medium from being conveyed to the image forming unit 40 in a state where a plurality of recording media are overlapped.

  FIG. 3 shows how the main opening / closing unit 20 and the intermediate transfer belt unit 60 are opened and closed with respect to the image forming apparatus main body 12 and how the image forming unit 200 is attached to and detached from the image forming apparatus main body 12. ing.

  As shown in FIG. 3, when the main opening / closing portion 20 is opened with respect to the image forming apparatus main body 12, the intermediate transfer belt unit 60 and the cleaning device 96 of the transfer device 58 move together with the main opening / closing portion 20. That is, the intermediate transfer belt unit 60 and the cleaning device 96 are opened and closed integrally with the main opening / closing portion 20 with respect to the image forming apparatus main body 12.

  When the main opening / closing part 20, the intermediate transfer belt unit 60 and the cleaning device 96 are integrally opened with respect to the image forming apparatus main body 12, an opening 36 is formed in the image forming apparatus main body 12. Then, the image forming units 200Y, 200M, 200C, and 200K are attached to and detached from the image forming apparatus main body 12 through the openings 36, respectively. The collection container 260 is integrated with the image forming unit 200K as described above. Therefore, the collection container 260 is attached to and detached from the image forming apparatus main body 12 integrally with the image forming unit 200K.

  In FIG. 3, an area A surrounded by an alternate long and short dash line is densely arranged with various units and parts including the electrical system. Securing is essential.

(Optical scanning device)
As shown in FIGS. 4 to 6, the optical scanning device 41 is composed of one unit common to the four image forming units 200Y, 200M, 200C, and 200K, and includes four semiconductor lasers 102Y, 102M, 102C, 102K is modulated according to color material gradation data of each color, and exposure light LY, LM, LC, LK is emitted from these semiconductor lasers according to the gradation data.

  Further, the optical scanning device 41 has a structure in which a box-shaped housing 100 is closed with a lid 101, and the light source of each exposure light L and the exposure light L are scanned in the main scanning direction in the internal space. The optical member for attaching is suitably attached to the location. On the cover 101 attached to the upper surface of the housing 100, four exposure lights LY, LM, LC, and LK are applied to the photosensitive drums 210Y, 210M, 210C, and 210K of the image forming units 200Y, 200M, 200C, and 200K. A window (not shown) is provided for exiting toward the screen.

  Here, the exposure lights LY, LM, LC, and LK output from the optical scanning device 41 are scanned and exposed at exposure points on the photosensitive drums 210Y, 210M, 210C, and 210K.

  As shown in FIGS. 4 to 6, the housing 100 of the optical scanning device 41 is molded into a rectangle (generally a rectangle) in plan view (see FIG. 6). In addition, the arrow F shown to each figure (FIGS. 4-6) has each shown the same direction.

  The shape of the housing 100 is not particularly limited, but a space for arranging the components described later and the optical paths of the exposure light LY, LM, LC, and LK to be main-scanned as described above are secured. Set based on each of the spaces.

  The housing 100 has a two-stage structure for component placement. On the lower side of this two-stage structure, semiconductor lasers 102Y, 102M, 102C, and 102K, which are light emission sources of exposure light LY, LM, LC, and LK, and polygon mirror 104, and semiconductor lasers 102Y, 102M, 102C, and 102K, and polygons Light source optical systems such as collimator lenses 103Y, 103M, 103C, and 103K disposed on the optical path between the mirror 104 and the fθ lens 108 and fθ lens 108 disposed on the downstream side of the optical path of the polygon mirror 104. An all-exposure light reflecting mirror 110 that guides the exposure light L to the upper stage is disposed (see FIG. 5).

  On the other hand, a plurality of reflecting mirrors 112YM and 112M for securing the necessary optical path length by selectively entering and reflecting the exposure light reflected by the all-exposure light reflecting mirror 110 on the upper stage of the two-stage structure. , 112CK, and 112C, and finally cylinder mirrors 114Y, 114M, 114C, and 114K serving as final stage reflecting mirrors for guiding the exposure light LY, LM, LC, and LK in the directions of the photosensitive drums 210Y, 210M, 210C, and 210K Has been. More specifically, the four light (CMYK) exposure lights LY, LM, LC, and LK necessary for color image formation are supplied to the photosensitive drums 210Y, 210M, 210C, and 210K for the respective colors with the same optical path length. The exposure light L reflected by the total exposure light reflecting mirror 110 is reflected twice or three times by the reflecting mirrors 112YM, 112M, 112CK, 112C and the final stage reflecting mirrors 114Y, 114M, 114C, 114K. It is configured.

  Note that an SOS sensor 115 is disposed at the corner of the housing (upper right corner of FIG. 6), and the exposure timing LS is input to synchronize the image recording timing.

  By the way, in the optical path of the exposure light L in the housing 100, the main scanning length becomes longer as it becomes downstream. For this reason, the reflecting mirrors 112YM, 112M, 112CK, and 112C and the final stage reflecting mirrors 114Y, 114M, 114C, and 114K arranged on the upper stage of the housing 100 are matched to the main scanning lengths of the exposure lights LY, LM, LC, and LK. Thus, the length of the housing 100 is required to be spanned between the side walls facing each other (left and right side wall portions 100S in FIG. 6). On the other hand, since the exposure light L is condensed in the sub-scanning direction orthogonal to the main scanning direction by the cylinder lens or the like, the reflecting mirrors 112YM, 112M, 112CK, 112C arranged in the upper stage and the final stage The reflecting mirrors 114Y, 114M, 114C, and 114K have an elongated structure in the main scanning direction (longitudinal direction)> sub-scanning direction (short side direction). Further, the thickness dimension is suppressed to the minimum necessary to secure the upper optical path space of the housing 100. Note that “elongated” as used herein is merely a sensory expression when visually observed, and it is essential to maintain the relationship of main scanning dimension> sub-scanning dimension as in the present embodiment. Although not a requirement, in reality, a shape (rectangular shape) that a person skilled in the art feels as “elongate” is applied.

  Here, the representative reflecting mirror 112 </ b> M is positioned in a state where both ends in the longitudinal direction are accommodated in rectangular grooves 100 </ b> A formed in the side walls 100 </ b> S facing each other of the housing 100. In addition, the positioning structure of the reflecting mirror 112M described below can be applied to other reflecting mirrors.

  The positioning of the reflection mirror 112M is based on rectangular block datums 116A to 116C provided on the inner wall of the groove 100A.

  7 and 8 show enlarged views of the groove 100A formed in the side wall 100S.

  As shown in FIGS. 7 and 8, two rectangular datums 116A and 116B protrude from the vertical wall surface portion of the inner wall of the side wall portion 100S, and one rectangular datum 116C protrudes from the bottom surface portion. The rectangular parallelepiped datums 116A, 116B, and 116C are basically formed when the housing 41 is molded. However, the dimensional tolerance of the protruding shape is stricter than other molding points, and the positioning standard ( Datum).

  The datums 116A and 116B are abutted against the vertical surface (reflection surface or the back surface thereof) of the reflecting mirror 112M, and the datum 116C is abutted with the downward surface (thick surface) of the reflecting mirror 112M. The abutted state is the positioning position of the reflecting mirror 112M. The longitudinal direction of the reflecting mirror 112M does not require a particularly strict positioning.

  The reflecting mirror 112 </ b> M that is abutted against the three datums 116 </ b> A to 116 </ b> C is held by the elastic force of the leaf spring member 118.

  The leaf spring member 118 in the present embodiment is made of metal, and is bent in a substantially U shape in accordance with the shape (both vertical wall surface portions and bottom surface portion) of the groove portion 100A.

  The leaf spring member 118 is accommodated in the groove portion 100A. At this time, the datums 116A to 116C are present on the movement locus during the accommodation.

  For this reason, the leaf spring member 118 has a width dimension x2 of a dimensional tolerance that fits closely to the longitudinal dimension x1 of the reflecting mirror 112M in the datum 116A, 116B on the vertical plate portion facing the datum 116A, 116B. A vertical hole 120 is formed.

  The vertical hole portion 120 passes through a corner of the leaf spring member 118 and the bottom plate portion and extends to the bottom plate portion. A rectangular strip escape hole 122 having a width dimension x3 larger than the width dimension x2 is formed in the bottom plate portion of the leaf spring member 118, and the longitudinal groove 120 (an extension thereof) communicates with the escape hole section 122. is doing. The escape hole 122 serves to avoid interference with the datum 116C formed on the bottom surface of the groove 100A, but fits closely to the datum 116C, similar to the vertical hole 120. It is good also as such a dimension.

  The leaf spring member 118 in which the vertical hole portion 120 and the relief hole portion 122 are formed is in close contact with the vertical wall surface portion and the bottom surface portion of the groove portion 100A without interfering with the datums 116A to 116C when being accommodated in the groove portion 100A. . At this time, the position of the leaf spring member 118 in the longitudinal direction of the reflecting mirror 112M is strictly determined by the fitting dimension tolerance between the dimension x1 of the datums 116A and 116B and the dimension x2 of the vertical hole 118. .

  In this leaf spring member 118, a tongue piece 123 bent at 90 ° is formed so as to face the longitudinal end face of the reflecting mirror 112M from the side end face of the longitudinal plate part in which the longitudinal hole part 120 is formed. ing. The tongue piece 123 serves as a stopper for the reflection mirror 112M in the longitudinal direction.

Further, a U-shaped groove in which the U-shaped shape of the leaf spring member 118 and the top and bottom are reversed is provided on the vertical plate portion on the opposite side of the vertical plate in which the vertical hole portion 120 is formed. The inner portion of the vertical plate is bent outward based on a line connecting both ends of the groove. Hereinafter, the bent portion is referred to as a locking portion 124. On the other hand, a concave portion 100B is formed in the vertical wall surface portion of the groove portion 100A of the side wall portion 100S. The locking portion 124 is accommodated in the recess 100B.

  That is, when the leaf spring member 118 is accommodated in the groove portion 100A from above in FIG. 7, the locking portion 124 hits the upper end corner portion of the groove portion 100A, and the protrusion amount decreases against its urging force. If the leaf spring member 118 is continuously accommodated and reaches the bottom surface of the groove 100A, the locking portion 124 faces the recess 100B and returns to the protruding state of the base by its own urging force. In this state, the locking portion 124 is prevented from coming off, and the leaf spring member 118 is held in the groove portion 100A.

  Further, in the leaf spring member 118, the upper end of the vertical wall surface portion on which the locking portion 124 is formed is bent and extended in a U shape (or a V shape, such as an acute angle). Hereinafter, this extended portion is referred to as a pressing portion 126.

  The pressing portion 126 is formed with a hemispherical pressing protrusion 126A. The pressing portion 126 has a role of pressing the reflecting mirror 112M that is positioned by being abutted against the datums 116A to 116C in the direction of the datums 116A and 116B by its own elastic force, and actually contacts the reflecting mirror 112M. This is the pressing protrusion 126A. That is, the reflecting mirror 112M is pressed with a point (pressing protrusion 126A).

  Here, since the leaf spring member 118 itself is positioned on the datums 116A to 116B, the pressing point does not move in the longitudinal direction of the reflecting mirror 112M, and the pressing portion 126 (pressing) facing the datums 116A and 116B is pressed. The relative positional relationship with the protrusion 116A) does not change. In the present embodiment, the two are opposed to each other, and since the reflecting mirror 112M that is abutted and positioned on the datums 116A to 116C is disposed therebetween, the force that deflects the reflecting mirror 112M in the longitudinal direction does not work. And this holding state is maintained.

  The operation of this embodiment will be described below.

(Image formation procedure)
The image data is further converted into color material gradation data of four colors of yellow (Y), magenta (M), cyan (C), and black (K), and sequentially output to the optical scanning device 41. In the optical scanning device 41, each exposure light L is emitted according to the color material gradation data of each color, and the photosensitive drums 210Y, 210M, 210C, and 210K are scanned and exposed, and latent images (electrostatic latent images). Is formed.

  The electrostatic latent images formed on the photosensitive drums 210Y, 210M, 210C, and 210K are respectively yellow (Y), magenta (M), cyan (C), and black (K) toner images by the developing unit. (Development). The toner images of each color sequentially formed on the photosensitive drums 210Y, 210M, 210C, and 210K of the image forming units 200Y, 200M, 200C, and 200K are intermediated by the four primary transfer rolls 80Y, 80M, 80C, and 80K. Multiple transfer is sequentially performed on the transfer belt 62.

  The toner images of each color transferred onto the intermediate transfer belt 62 are secondarily transferred onto the conveyed recording paper by the secondary transfer roll 86. Then, the toner images of the respective colors on the recording paper are fixed by the fixing device 50, and the recording paper after fixing is discharged.

  Residual toner, paper dust, and the like are removed from the surfaces of the photosensitive drums 210Y, 210M, 210C, and 210K after the toner image transfer process is completed. Further, residual toner, paper dust and the like on the intermediate transfer belt 62 are removed by the cleaning device 96.

(Reflecting mirror holding structure in optical scanning device)
In the image forming process, particularly in the case of a color image, the four color scanning lines may be displaced. There are various kinds of deviation such as deviation in the main scanning direction, sub-scanning direction, oblique deviation, arcuate deviation, magnification deviation, etc., but in this embodiment, mainly in the optical scanning device 41. As means for eliminating the factor of magnification shift, an attachment structure of a reflection mirror (for example, the reflection mirror 112M) is shown.

  The reflection mirror 112M is stretched over the side wall portions 100S facing each other of the housing 100 of the optical scanning device 41. In other words, the reflection mirror 112M has an elongated shape having a length corresponding to the dimension between the pair of side wall portions 100S of the housing 100. The longer the reflecting mirror 112M is, the easier it is to bend in the longitudinal direction, and this bending causes a magnification shift.

  If the amount of deflection of the reflecting mirror 112M is constant, for example, it can be corrected in a controlled manner. However, each time the holding state of the reflecting mirror 112M changes, in a configuration in which the amount of deflection is different, it is necessary to change the correction amount according to the performance of each optical scanning device, or beyond the assumed correction range. There is a possibility.

  Therefore, in the present embodiment, when the reflecting mirror 112M is housed in the groove portion 100A of the side wall portion 100S of the housing 100 and is held using the leaf spring member 118, the leaf spring member 118 positions the reflecting mirror 112M. A structure in which the holding position does not change with respect to the datum (see holding structures 1 and 2) was adopted.

(Holding structure 1)
The leaf spring member 118 was positioned by applying at least one of the datums 116A to 116C for positioning the reflecting mirror 112M.

  In this embodiment, two datums 116A and 116B are applied. A longitudinal hole 120 is provided in the leaf spring member 118 along the two datums 116A and 116B aligned in the longitudinal direction.

  Here, the relationship between the reflection mirror longitudinal dimension x1 of the datums 116A and 116B and the width dimension x2 of the vertical hole 120 is set to a tolerance that allows the datums 116A and 116B to closely fit the vertical hole 120. Therefore, when the leaf spring member 118 is accommodated in the groove portion 100A, the position in the longitudinal direction of the reflection mirror 112M is determined reliably (strictly).

  In addition, since the two datums 116A and 116B are applied (two-point support), rotation during one-point support is prevented. In this embodiment, since the datums 116A to 116C themselves are rectangular blocks and have sufficient vertical dimensions, even if the leaf spring member 118 is positioned with reference to one term 116A (or 116B or 116C), It does not rotate.

(Holding structure 2)
The bending direction of pressing for pressing the reflecting mirror 112M against the datums 116A and 116B by the elastic force of the leaf spring member 118 is set to a direction orthogonal to the longitudinal direction of the reflecting mirror 112M.

  When the pressing portion 126 is formed on the leaf spring member 118, when the bending direction of the pressing portion 126 is the longitudinal direction of the reflecting mirror 112M, the pressing position changes in an arc shape depending on the degree of bending. For example, an attachment error of the leaf spring member 118 to the groove portion 100A (thickness direction of the reflection mirror 112M), an error in forming the pressing portion 126, a thickness dimension error of the reflection mirror 112M, and the like can be given. Although the change in the pressing position itself is basically no problem, the relative position of the pressing input points on the front and back surfaces (the reflecting surface and the back surface) of the reflecting mirror 112M changes as the relative positional relationship with the datums 116A and 116B changes. The change affects the amount of deflection of the reflecting mirror 112M.

  Therefore, in the present embodiment, the bending direction of the pressing portion 126 is a direction orthogonal to the longitudinal direction of the reflecting mirror 112M. In this case, even if the bending degree changes, the pressing position does not change in the longitudinal direction of the reflecting mirror 112M. In other words, since the relative positional relationship between the datums 116A and 116B and the pressing position of the pressing portion 126 is not lost, the deflection amount of the reflecting mirror 112M does not vary.

  In this embodiment, the pressing portion 126 is provided with a hemispherical pressing protrusion 126A, and the pressing point of the pressing protrusion 126A and the supporting points (supporting regions) of the datums 116A and 116B are sandwiched between the reflecting mirrors 112M. Therefore, the reflection mirror 112M is not bent by the support.

  Since the plate spring portion 118 having the above-described configuration does not protrude from the upper opening of the groove portion 100A, the height dimension of the optical scanning device 41 is prevented from being increased compared to the case where the plate spring member protrudes.

  In the present embodiment, the reflection mirror 112M is applied as the target of the holding structure, but other optical members such as the reflection mirrors 112YM, 112CK, and 112C or the final stage reflection mirrors 114Y, 114M, 114C, and 114K are targets. It is good.

  In the present embodiment, the plate spring member 118 is formed by bending a metal plate material into a U-shape so as to face the vertical wall surface and bottom surface of the groove 100A of the housing 100. It is not limited. Below, the modification (refer the modification 1, 2) of the leaf | plate spring member 118 is shown. In the first and second modified examples, the same components as those in the present embodiment are denoted by the same reference numerals, and the description of the configurations may be omitted.

(Modification 1)
As shown in FIGS. 9 and 10, the first modification of the present embodiment is characterized in that an L-shaped leaf spring member 128 is applied.

  The plate spring member 128 has a vertical plate portion and a bottom plate portion formed with an engaging portion 124 and a pressing portion 126 (pressing projection portion 126A) bent in an L shape.

  A cutout portion 130 having a width dimension equivalent to that of the vertical hole portion 120 according to the present embodiment is formed in the bottom plate portion. The width dimension x3 of the notch 130 and the reflection mirror longitudinal dimension x1 of the datum 116C have a dimensional tolerance relationship that fits closely.

  That is, the leaf spring member 128 of Modification 1 is configured such that the reflecting mirror 112M is positioned in the longitudinal direction by the notch 130 and the datum 116C. At this time, even if it is a single datum 116C, the leaf spring member 130 does not rotate because the datum 116C itself has a sufficient dimension z in the reflection mirror thickness direction.

  Note that the pressing portion 126 (the pressing protrusion 126A) and the locking portion 124 are formed on the vertical plate portion facing the vertical plate portion on which the vertical hole portion 120 is formed, as in the present embodiment.

(Modification 2)
As shown in FIGS. 11 and 12, the modification 2 in the present embodiment is characterized in that the reflecting mirror 112M is first positioned in the groove 100A (positioning by contacting the datums 116A to 116C) as an assembling process. After that, the leaf spring member 138 is attached to the groove portion 100A.

  For this reason, the leaf spring member 118 does not face the bottom surface portion of the groove portion 100A, but instead has a U-shape in which a ceiling plate portion is formed so as to close the opening of the groove portion 100A.

  The other shapes are the same as in the present embodiment. A notch 140 and a tongue piece 123 having the same function as the vertical hole 120 are formed on one of the vertical plate portions, and a pressing portion 126 (pressing protrusion) is formed on the other side. 126A) and a locking portion 124 are formed. In addition, since the leaf | plate spring part 138 has made the top-and-bottom direction reverse with respect to this Embodiment, the press part 126 is bent and formed from the front-end | tip (lower end part) of said other vertical board part. However, the condition of bending in the direction orthogonal to the longitudinal direction of the reflecting mirror 112M is kept.

  In the second modification, a part (ceiling board) of the leaf spring member 138 exists above the reflecting mirror 112M, so that the reflecting mirror 112M is prevented from falling off and an impact is not transmitted from the outside to the reflecting mirror 112M. The

  The holding structure shown in the present embodiment and each of the first and second modifications may be applied not only to the optical scanning device for writing an image but also to an optical member used in a scanning system for reading an image. .

10 Image forming apparatus 41 Optical scanning device (optical device)
100 Housing 100A Groove (Mounting part)
100S Side wall part 101 Cover body 110 Total exposure light reflection mirror 112YM, 112M, 112CK, 112C Reflection mirror (optical member)
114Y, 114M, 114C, 114K Final reflection mirror (optical member)
116A, 116B, 116C Datum (positioning part)
118 Leaf spring member 120 Vertical hole portion 122 Escape hole portion 123 Tongue piece portion 124 Locking portion 126 Pressing portion 126A Pressing projection portion

Claims (11)

A rectangular optical member that deflects incident light;
Positioning for positioning in the thickness direction intersecting both the longitudinal direction and the width direction intersecting the longitudinal direction of the optical member, and the thickness direction intersecting both the longitudinal direction and the width direction. A mounting portion formed with a portion;
A spring member provided with a holding part that is positioned in the longitudinal direction with respect to the attachment part using the positioning part and presses and holds the optical member with an elastic force in the thickness direction;
An optical device.   The optical device according to claim 1, wherein the spring member is positioned in a rotation direction around the thickness direction by the positioning unit.   The optical device according to claim 1, wherein the holding portion has a leaf spring shape bent along the width direction, and a spherical protrusion is formed facing the optical member. .   4. The datum according to claim 1, wherein the positioning portion is a datum protruding in a block shape, the optical member is positioned by a protruding front end surface of the datum, and the spring member is positioned by a side surface of the datum. 2. An optical device according to item 1.   The said optical member is pinched | interposed and hold | maintained between the said datum and the holding part of the said spring member, The said press point of the said holding part is located so that it may oppose within the range of the protrusion front end surface of the said datum. The optical device described. When the light is scanned in one direction by the scanning mechanism, an optical member for setting a longitudinal dimension according to the scanning width and deflecting the scanned light;
Positioning for positioning in the thickness direction intersecting both the longitudinal direction and the width direction intersecting the longitudinal direction of the optical member, and the thickness direction intersecting both the longitudinal direction and the width direction. A mounting portion formed with a portion;
A spring member provided with a holding part that is positioned in the longitudinal direction with respect to the attachment part using the positioning part and holds the optical member by pressing it in the thickness direction with an elastic force;
An optical scanning device.   The optical scanning device according to claim 6, wherein the spring member is positioned by the positioning portion in a rotational direction centered on the longitudinal direction and the thickness direction.   8. The optical scanning according to claim 6, wherein the holding portion has a leaf spring shape bent along the width direction, and a spherical protrusion is formed facing the optical member. 9. apparatus.   The datum in which the positioning portion protrudes in a block shape, the optical member is positioned by a protruding front end surface of the datum, and the spring member is positioned by a side surface of the datum. 2. An optical scanning device according to item 1.   The said optical member is pinched | interposed and hold | maintained between the said datum and the holding part of the said spring member, The said pressing point of the said holding part is located so that it may oppose within the range of the protrusion front end surface of the said datum. The optical scanning device described. The optical scanning device according to any one of claims 6 to 10, and
An image forming unit that forms an electrostatic latent image on the image carrier using the optical scanning, and then develops and transfers the image onto a recording sheet;
An image forming apparatus.

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