JP2011215312A - Optical scanner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress movement in an optical axis direction and a main-scanning direction of a lens.SOLUTION: An optical scanner includes: a lens (fθ lens 54) through which a light beam passes; and a housing 50 which supports the lens. The lens has: a lens portion 54A having a pair of oblong lens surfaces 54D and 54E opposite to each other; a first positioning portion 110 provided on one of surfaces facing the optical axis direction of a flange portion 54B; and a second positioning portion 120 provided to project from a side surface 54F of a rib portion 54C. The housing 50 has: two first abutting portions 130 each abutting on the first positioning portion 110; and a second abutting portion 140 abutting on the second positioning portion 120 at two points. In the second positioning portion 120 and the second abutting portion 140, two contacts C1 and C2 hold the second positioning portion 120 in between in a longitudinal direction, and the second abutting portion 140 abuts on the second positioning portion 120 in a pressed state so as to press the lens toward the first abutting portion 130.

Description

  The present invention relates to an optical scanning device.

  In general, an image forming apparatus such as a laser printer is provided with an optical scanning device that exposes the surface of a photoreceptor. As such an optical scanning device, for example, as shown in Patent Document 1, a light source (semiconductor laser), a deflector (rotating polygonal mirror) that deflects and scans laser light, and laser light that is deflected and scanned includes A lens having a long lens (f-theta lens) that passes therethrough and a housing (optical box) that supports the lens or the like is known.

Japanese Patent Laid-Open No. 11-183819

  By the way, in the optical scanning device, in order to accurately scan the laser beam on the surface to be scanned such as the photosensitive member, the positional accuracy of the lens with respect to the housing is important. In particular, if the long lens is shifted (moved) in the optical axis direction or the longitudinal direction (main scanning direction), it becomes difficult to scan the laser beam on the surface to be scanned with high accuracy.

  The present invention has been made in view of the background as described above, and an object thereof is to provide an optical scanning device capable of suppressing movement of a lens in the optical axis direction and the main scanning direction.

  In order to achieve the above object, an optical scanning device of the present invention includes a light source, a deflector that deflects and scans a light beam from the light source in a main scanning direction, and a light beam that is deflected and scanned by the deflector. An optical scanning device comprising a lens that passes through and a housing that supports the lens, the lens having a pair of elongated surfaces facing each other, at least one of which has lens characteristics A lens portion that is a lens surface; flange portions provided at both ends in the longitudinal direction of the lens portion; a first positioning portion provided on one of the surfaces of the flange portion facing the optical axis direction; and the pair of pairs A second positioning portion provided at a position shifted in the sub-scanning direction with respect to the long surface, and the housing includes two first contact portions that contact the first positioning portion, and the lens. In the longitudinal direction of the two A second abutting portion that is provided between the abutting portions and abuts on the second positioning portion at two locations, and the second positioning portion and the second abutting portion are provided at the two locations. A contact point sandwiches the second positioning portion or the second contact portion in the longitudinal direction, and the contact is made with one side pressed against the other so as to push the lens toward the first contact portion. And

  According to the optical scanning device configured as described above, the second positioning portion of the lens and the second contact portion of the housing have two contact points sandwiching the second positioning portion or the second contact portion in the longitudinal direction. Therefore, the movement of the lens in the main scanning direction can be suppressed. Further, since the second positioning portion and the second contact portion are in contact with each other while pressing the other so as to push the lens toward the first contact portion, the movement of the lens in the optical axis direction is suppressed. be able to.

  According to the present invention, the second positioning portion of the lens and the second abutting portion of the housing have two contact points sandwiching the second positioning portion or the second abutting portion in the longitudinal direction, and the lens is in the first position. Since one abuts against the other so as to push toward the abutment portion, the lens can be prevented from moving in the optical axis direction and the main scanning direction.

1 is a diagram illustrating a schematic configuration of a laser printer including an optical scanning device according to a first embodiment of the present invention. It is a top view of the optical scanning device concerning a 1st embodiment. 1 is a cross-sectional view of an optical scanning device according to a first embodiment. It is a perspective view of an fθ lens. It is a perspective view which shows the structure of the principal part of a base frame. FIG. 6 is a plan view (a) when the fθ lens is assembled to the base frame, and an enlarged view (b) showing the second positioning portion and the second contact portion at that time. It is a figure for demonstrating the 2nd positioning part and 2nd contact part of 2nd Embodiment, The top view (a) when an f (theta) lens is assembled | attached to a base frame, and the 2nd positioning part and 2nd at that time It is an enlarged view (b) which shows 2 contact parts. It is a figure for demonstrating the 2nd positioning part and 2nd contact part of 3rd Embodiment, the top view (a) when an f (theta) lens is assembled | attached to a base frame, the 2nd positioning part at that time, and 2nd It is an enlarged view (b) which shows 2 contact parts.

[First Embodiment]
Next, a first embodiment of the present invention will be described in detail with reference to the drawings as appropriate. In the following description, first, a schematic configuration of the image forming apparatus including the optical scanning device according to the present embodiment will be described, and then a detailed configuration of the optical scanning device will be described.

<Schematic configuration of laser printer>
As shown in FIG. 1, a laser printer 1 (image forming apparatus) includes a paper feeding unit 3 for feeding paper S and an image forming unit 4 for forming an image on the paper S in a main body casing 2. Mainly prepared.

  Here, in the description of the schematic configuration of the laser printer 1, the direction will be described with reference to the user who uses the laser printer 1. That is, the right side in FIG. 1 is “front”, the left side is “rear”, the front side is “left”, and the back side is “right”. Also, the vertical direction in FIG.

  The paper feed unit 3 is provided at a lower portion in the main body casing 2 and mainly includes a paper feed tray 31, a paper pressing plate 32, and a paper feed mechanism 33. The paper S stored in the paper feed tray 31 is moved upward by the paper pressing plate 32 and supplied to the image forming unit 4 by the paper feed mechanism 33.

  The image forming unit 4 mainly includes an optical scanning device 5, a process cartridge 6, and a fixing device 7.

  The optical scanning device 5 is arranged at the upper part in the main casing 2 and is configured to emit a laser beam (see a chain line) based on image data and expose the surface of the photosensitive drum 61 to form an electrostatic latent image. Has been. The detailed configuration of the optical scanning device 5 will be described later.

  The process cartridge 6 is disposed below the optical scanning device 5 and is configured to be detachably mounted to the main casing 2 through an opening formed when a front cover (reference number omitted) provided on the main casing 2 is opened. It has become. The process cartridge 6 includes a photosensitive drum 61, a charger 62, a transfer roller 63, a developing roller 64, a layer thickness regulating blade 65, a supply roller 66, and a toner storage unit that stores toner (developer). 67 mainly.

  In the process cartridge 6, the surface of the photosensitive drum 61 is uniformly charged by the charger 62 and then exposed to the laser beam from the optical scanning device 5, so that the photosensitive drum 61 is based on the image data. An electrostatic latent image is formed. Further, the toner in the toner container 67 is supplied to the developing roller 64 via the supply roller 66 and enters between the developing roller 64 and the layer thickness regulating blade 65 to form a thin layer having a constant thickness. Supported on.

  The toner carried on the developing roller 64 is supplied from the developing roller 64 to the electrostatic latent image formed on the photosensitive drum 61. As a result, the electrostatic latent image is visualized and a toner image is formed on the photosensitive drum 61. Thereafter, the sheet S is conveyed between the photosensitive drum 61 and the transfer roller 63, whereby the toner image on the photosensitive drum 61 is transferred onto the sheet S.

  The fixing device 7 is provided behind the process cartridge 6, and mainly includes a heating roller 71 and a pressure roller 72 that is disposed to face the heating roller 71 and presses the heating roller 71. In the fixing device 7, the toner image transferred onto the paper S is thermally fixed while the paper S passes between the heating roller 71 and the pressure roller 72. The sheet S on which the toner image has been heat-fixed is conveyed on the conveyance path 23 by the conveyance roller 73 and is discharged from the conveyance path 23 onto the paper discharge tray 22 by the discharge roller 24.

<Detailed configuration of optical scanning device>
Next, a detailed configuration of the optical scanning device 5 will be described. In the following description, the downstream side in the traveling direction of the laser light emitted from the light source device 51 is simply referred to as “downstream side”.

  As shown in FIGS. 2 and 3, the optical scanning device 5 includes a light source device 51, a polygon mirror 52 as an example of a deflector, a polygon motor 53, and an fθ lens 54 as an example of a lens. And a reflecting mirror 55 and a cylindrical lens 56 are mainly provided.

  The light source device 51 is a semiconductor laser light source 51A as an example of a light source that emits laser light (light beam), or a coupling lens 51B that condenses the laser light emitted from the semiconductor laser light source 51A and converts it into a parallel light beam. It is a well-known apparatus comprised including such as.

  The polygon mirror 52 is disposed on the downstream side of the light source device 51, and the six side surfaces of the hexagonal prism are reflecting surfaces. The polygon mirror 52 reflects the laser light from the light source device 51 while rotating at high speed, and deflects it in the main scanning direction (substantially left-right direction in FIG. 2) and scans it at an equal angular velocity. The polygon motor 53 is a known motor for driving the polygon mirror 52 to rotate.

  The fθ lens 54 is a scanning lens that is disposed on the downstream side of the polygon mirror 52 and through which the laser light deflected and scanned by the polygon mirror 52 passes. The fθ lens 54 converts the laser beam scanned by the polygon mirror 52 at a constant angular speed so as to scan at a constant speed.

  As shown in FIGS. 4 and 5, the fθ lens 54 mainly includes a lens portion 54A, a pair of flange portions 54B, a pair of rib portions 54C, a pair of first positioning portions 110, and a second positioning portion 120. Have.

  The lens portion 54A is a portion through which the laser beam passes, and has a pair of long surfaces (two lens surfaces 54D and 54E) that are long in the main scanning direction facing each other. This pair of long surfaces condenses the laser beam scanned at a lens characteristic, specifically, an equiangular velocity, onto the surface (surface to be scanned) of the photosensitive drum 61 and scans at an equal velocity. Thus, the lens surfaces 54D and 54E have a function of conversion.

  The flange portion 54B is provided so as to extend outward in the longitudinal direction from both end portions in the longitudinal direction of the lens portion 54A.

  The rib portion 54C protrudes from the lens portion 54A (the portion on the lens surface 54D side) and the flange portion 54B toward the outside in the sub-scanning direction, and is provided so as to extend along the longitudinal direction (main scanning direction).

  The first positioning portion 110 is one of the surfaces facing the optical axis direction of the flange portion 54B, specifically, out of the plane on the lens surface 54E side out of the plane orthogonal to the optical axis direction of the flange portion 54B. It protrudes toward The first positioning portion 110 is formed in a substantially cylindrical shape having a circular top surface, and when the fθ lens 54 is assembled to the housing 50, the top surface is in contact with a first contact portion 130 described later. Abut (see FIG. 2).

  The second positioning unit 120 is located at a position (viewed from the optical axis direction) that is shifted in the sub-scanning direction (a direction perpendicular to the main scanning direction and the optical axis direction) with respect to the two lens surfaces 54D and 54E (a pair of long surfaces). The lens surfaces 54D and 54E are positioned so as not to overlap the lens surfaces 54D and 54E. Specifically, the rib surfaces 54C (fθ lenses 54) are provided so as to protrude outward in the sub-scanning direction. More specifically, the second positioning portion 120 is provided on the lens surface 54E side of the central portion in the longitudinal direction of the side surface 54F (fθ lens 54).

  The second positioning portion 120 is formed in a substantially triangular prism shape having a triangular top surface. More specifically, as shown in FIGS. 6A and 6B, the second positioning portion 120 includes a surface 123 extending in the main scanning direction along the end surface of the rib portion 54C on the lens surface 54E side, and a surface 123. Are substantially triangular prisms having two inclined surfaces 121 and 122 extending from both ends in the main scanning direction to the lens surface 54D side and toward the optical axis of the fθ lens 54 indicated by a chain line. With such a configuration, the two inclined surfaces 121 and 122 have a V-shape that tapers toward the optical axis direction, specifically, toward the lens surface 54D when viewed from the sub-scanning direction.

  In the present embodiment, the configuration in which the second positioning unit 120 is provided on both of the pair of side surfaces 54F (see FIG. 5) of the fθ lens 54 is shown, but the present invention is not limited to this. It is good also as a structure provided only in one of a pair of side surfaces 54F.

  2 and 3, the reflecting mirror 55 is disposed on the downstream side of the fθ lens 54, reflects the laser light that has passed through the fθ lens 54, and folds the optical path thereof, so that the laser light is transmitted to the cylindrical lens 56. It is intended.

  The cylindrical lens 56 is a scanning lens that is disposed on the downstream side of the reflecting mirror 55 and through which the laser light reflected by the reflecting mirror 55 passes. The cylindrical lens 56 refracts the laser light and converges it in the sub-scanning direction.

  In the optical scanning device 5, the laser light (see the chain line) based on the image data emitted from the light source device 51 is reflected or passed through the polygon mirror 52, the fθ lens 54, the reflecting mirror 55, and the cylindrical lens 56 in this order. High speed scanning is performed on the surface (scanned surface) of the drum 61 (see FIG. 1). As a result, the surface of the photosensitive drum 61 is exposed, and an electrostatic latent image based on the image data is formed on the photosensitive drum 61.

  The housing 50 is a substantially box-shaped member that supports the light source device 51, the fθ lens 54, and the like. More specifically, the housing 50 includes a box-shaped (container-shaped) base frame 50A whose upper part (the upper part in FIG. 3) is opened, and a lid frame 50B that is attached so as to cover the opened part of the base frame 50A. have.

  As shown in FIG. 5, the base frame 50 </ b> A mainly has a first contact portion 130, a second contact portion 140, and a leaf spring portion 150 on the bottom wall 50 </ b> C of the box (vessel). .

  The first contact portion 130 is provided so as to protrude upward from the bottom wall 50C in the figure. More specifically, the first abutting portions 130 are provided one by one (two in total) at positions that abut on the first positioning portion 110 of the fθ lens 54 assembled to the base frame 50A (housing 50). (See FIG. 2).

  The second contact portion 140 is a pin-like (substantially cylindrical) portion that protrudes upward from the bottom wall 50C in the figure, and is 2 in the longitudinal direction of the fθ lens 54 (the direction in which the first contact portions 130 are arranged). Two are provided between the first contact portions 130.

  As shown in FIGS. 6A and 6B, the two second abutting portions 140 have a curved surface relative to the second positioning portion 120 when the fθ lens 54 is assembled to the housing 50. Abut at two places (one place at a time). More specifically, the second contact portion 140 contacts the two inclined surfaces 121 and 122 of the second positioning portion 120 in the longitudinal direction of the fθ lens 54. Accordingly, the second positioning portion 120 and the two second contact portions 140 have two contact points C1 and C2 sandwiching the second positioning portion 120 in the longitudinal direction.

  The second contact portion 140 is elastically deformable. Specifically, the second contact portion 140 is provided so as to be elastically bent in the direction of a white arrow when the fθ lens 54 is assembled. As a result, the second contact portion 140 bends in the direction of the white arrow by assembling the fθ lens 54 to the housing 50, and the second positioning portion 120 is moved by the restoring force (force to return to the original shape). Press in the direction of the thick arrow.

  The force with which the second contact portion 140 presses the second positioning portion 120 acts as a force that presses the second positioning portion 120 (fθ lens 54) toward the lens surface 54E. Therefore, the second positioning part 120 and the two second abutting parts 140 are configured so that the second abutting part 140 is the second abutting part so as to push the first positioning part 110 (the fθ lens 54) toward the first abutting part 130. It abuts in a state where the positioning part 120 is pressed.

  The second contact portion 140 may be integrally formed with the base frame 50A (housing 50) or a member attached to the base frame 50A (housing 50) by being inserted into the bottom wall 50C. Also good.

  The leaf spring portion 150 sandwiches both end portions (the flange portion 54B and the first positioning portion 110) in the longitudinal direction of the fθ lens 54 between the leaf spring portion 150 and the first contact portion 130. This is a portion that is biased toward 130. The fθ lens 54 is supported by the base frame 50 </ b> A (housing 50) by sandwiching both end portions in the longitudinal direction between the first contact portion 130 and the leaf spring portion 150.

According to the above, the following effects can be obtained in the present embodiment.
Since the second positioning portion 120 of the fθ lens 54 and the second contact portion 140 of the housing 50 have the two contact points C1 and C2 sandwiching the second positioning portion 120 in the longitudinal direction, the main scanning of the fθ lens 54 is performed. Movement in the direction can be suppressed. Further, the second positioning portion 120 and the second contact portion 140 are contacted with the second contact portion 140 pressed against the second positioning portion 120 so as to press the fθ lens 54 toward the first contact portion 130. Therefore, the movement of the fθ lens 54 in the optical axis direction can be suppressed.

  Further, in the present embodiment, the force with which the second contact portion 140 presses the second positioning portion 120 (see the thick arrow in FIG. 6B) is that the two second contact portions 140 are second in the longitudinal direction. It also acts as a force for pressing the positioning part 120. With such a configuration, the main scanning of the second positioning portion 120 (fθ lens 54) is compared with a configuration in which the second contact portion 140 merely sandwiches the second positioning portion 120 (a configuration in which the second contact portion 140 is not pressed). Movement in the direction can be more reliably suppressed.

  Since the second positioning portion 120 is provided at the center in the longitudinal direction (main scanning direction) of the fθ lens 54, each first positioning portion 110 is directed toward the corresponding first contact portion 130 with a substantially uniform force. Can be pressed. Thereby, the movement of the fθ lens 54 in the optical axis direction can be more reliably suppressed. Moreover, since the force which presses each 1st positioning part 110 toward the corresponding 1st contact part 130 becomes substantially uniform, since the 2nd positioning part 120 can be clamped stably, the f (theta) lens 54 can be held. The movement in the main scanning direction can also be more reliably suppressed. Furthermore, since the second positioning portion 120 is provided at the center in the longitudinal direction, it is possible to suppress the positional deviation of the fθ lens 54 (especially the optical axis) due to a temperature change.

  The second positioning portion 120 has two inclined surfaces 121 and 122 having a V-shape that tapers in the optical axis direction, and the two second contact portions 140 sandwich the two inclined surfaces 121 and 122. Therefore, the force by which the second contact portion 140 presses the second positioning portion 120 (see the thick arrow in FIG. 6B) is the force that pushes the fθ lens 54 toward the first contact portion 130. Then, the two second contact portions 140 can be used as a force for pressing the second positioning portion 120 in the longitudinal direction. Thereby, the movement of the fθ lens 54 in the optical axis direction and the main scanning direction can be more reliably suppressed.

  In the present embodiment, the second positioning portion 120 has two inclined surfaces 121 and 122, and two second contact portions 140 are provided so as to sandwich the two inclined surfaces 121 and 122. Although the structure which contact | abuts was illustrated, it is not limited to this. That is, the second abutting portion has two inclined surfaces that are tapered toward the optical axis direction, and two second positioning portions are provided to abut on the two inclined surfaces. It is good also as a structure. In this case, the two contact points sandwich the second contact portion in the longitudinal direction.

[Second Embodiment]
Next, a second embodiment of the present invention will be described. In the embodiment described below, the same components as those in the above-described embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  As shown in FIG. 7A, the fθ lens 54 of this embodiment includes a lens portion 54A having two lens surfaces 54D and 54E, a pair of flange portions 54B, a pair of rib portions 54C, and a pair of first lenses. It mainly has a first positioning part 110 and a second positioning part 220.

  The second positioning portion 220 is provided at a position shifted in the sub-scanning direction with respect to the two lens surfaces 54D and 54E, specifically, at the central portion in the longitudinal direction of the rib portion 54C. The second positioning portion 220 has a groove 221 having a V-shape in a plan view provided so as to cut out the end surface on the lens surface 54D side of the central portion in the longitudinal direction of the rib portion 54C. The groove 221 has a V shape that tapers in the optical axis direction, specifically toward the lens surface 54E side.

  The base frame 50A (housing 50) of the present embodiment mainly has two first contact portions 130, one second contact portion 240, and two leaf spring portions 150 on the bottom wall 50C. is doing.

  The second contact portion 240 is a cylindrical portion that protrudes from the bottom wall 50 </ b> C, and is provided between the two first contact portions 130 in the longitudinal direction of the fθ lens 54. The second contact portion 240 enters the groove 221 provided in the fθ lens 54 when the fθ lens 54 is assembled to the housing 50, and is against the inner surface (second positioning portion 220) of the groove 221. Abuts at two locations on the curved surface.

  The second contact portion 240 is provided so as to be elastically bent in the direction of the white arrow shown in FIG. 7B when the fθ lens 54 is assembled. Accordingly, the second contact portion 240 bends in the direction of the white arrow by assembling the fθ lens 54 to the housing 50, and presses the second positioning portion 220 in the direction of the thick arrow by the restoring force.

  According to such a configuration, the second positioning unit 220 and the second contact unit 240 cause the second contact unit 240 to push the fθ lens 54 toward the first contact unit 130. Since the contact is made in a pressed state, the movement of the fθ lens 54 in the optical axis direction can be suppressed. In addition, since the second positioning portion 220 and the second contact portion 240 have two contact points C1 and C2 sandwiching the second contact portion 240 in the longitudinal direction, the fθ lens 54 moves in the main scanning direction. Can be suppressed.

  The second contact portion 240 may be integrally formed with the housing 50, or may be a member attached to the housing 50 by being inserted into the bottom wall 50C.

  In the present embodiment, the second positioning portion 220 has the V-shaped groove 221 and the second contact portion 240 enters the groove 221 and contacts at two locations. It is not limited. That is, the second contact portion may have a V-shaped groove that tapers in the optical axis direction, and the second positioning portion may enter the groove and contact at two locations. In this case, the two contact points sandwich the second positioning portion in the longitudinal direction.

[Third Embodiment]
Next, a third embodiment of the present invention will be described.
As shown in FIG. 8A, the fθ lens 54 of the present embodiment includes a lens portion 54A having two lens surfaces 54D and 54E, a pair of flange portions 54B, a pair of rib portions 54C, and a pair of first lenses. The first positioning unit 110 and the second positioning unit 320 are mainly included.

  The second positioning portion 320 has a columnar shape, and similarly to the second positioning portion 120 of the first embodiment described above, a position shifted in the sub-scanning direction with respect to the two lens surfaces 54D and 54E, specifically Are provided so as to protrude from the center in the longitudinal direction of the side surface 54F of the rib portion 54C (fθ lens 54) toward the outside in the sub-scanning direction.

  The base frame 50A (housing 50) of the present embodiment mainly has a first contact portion 130, a second contact portion 340, and a leaf spring portion 150 on the bottom wall 50C.

  The second contact portions 340 are pin-like portions protruding from the bottom wall 50 </ b> C, and two second contact portions 340 are provided between the two first contact portions 130 in the longitudinal direction of the fθ lens 54. As shown in FIG. 8B, the two second contact portions 340 have a cylindrical shape, and are arranged such that the distance D1 between them is smaller than the diameter D2 of the second positioning portion 320. . Thereby, when the fθ lens 54 is assembled to the housing 50, the second abutting portion 340 abuts so as to sandwich the second positioning portion 320 (a portion near the lens surface 54D).

  Similarly to the second contact portion 140 of the first embodiment, the second contact portion 340 is provided so as to be elastically bent in the direction of the white arrow when the fθ lens 54 is assembled. ing. Accordingly, the second contact portion 340 is bent in the direction of the white arrow by assembling the fθ lens 54 to the housing 50, and presses the second positioning portion 320 in the direction of the thick arrow by the restoring force.

  According to such a configuration, the second positioning portion 340 and the two second abutting portions 340 cause the second abutting portion 340 to perform the second positioning so as to push the fθ lens 54 toward the first abutting portion 130. Since the contact is made in a state where the portion 320 is pressed, the movement of the fθ lens 54 in the optical axis direction can be suppressed. Further, since the second positioning portion 320 and the two second contact portions 340 have two contact points C1 and C2 sandwiching the second positioning portion 320 in the longitudinal direction, the fθ lens 54 moves in the main scanning direction. Can be suppressed.

  The second contact portion 340 may be integrally formed with the housing 50 or may be a member attached to the housing 50 by being inserted into the bottom wall 50C.

  Further, in the present embodiment, the second positioning portion 320 has a columnar shape, the second contact portion 340 has a columnar shape, two are provided, and the distance D1 between them is the second positioning portion 320. Although the configuration smaller than the diameter D2 is exemplified, the configuration is not limited to this. That is, one second abutting portion has a cylindrical shape, the second positioning portion has a cylindrical shape, and two are provided so that the distance between them is smaller than the diameter of the second abutting portion. Also good. In this case, the two contact points sandwich the second contact portion in the longitudinal direction.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to the said embodiment. About a concrete structure, it can change suitably in the range which does not deviate from the meaning of this invention.

  In the above embodiment, the second abutting portions 140, 240, and 340 press the second positioning portions 120, 220, and 320 so that the fθ lens 54 (lens) is pushed toward the first abutting portion 130. Although the structure which touches was illustrated, it is not limited to this. In other words, as long as the lens abuts so as to push the lens toward the first abutting portion, the second positioning portion may abut against the second abutting portion.

  In the above-described embodiment, the second contact portions 140, 240, and 340 themselves are provided so as to be elastically deformable, thereby realizing a configuration in which the fθ lens 54 (lens) is pushed toward the first contact portion 130. It is not limited. For example, the second contact portion may be provided so as to be slidable in the optical axis direction with respect to the housing, and may be biased toward one side in the optical axis direction by a biasing member such as a coil spring or a leaf spring. At this time, the urging member is elastically deformed (for example, compressed or bent) when the lens is assembled to the housing and the second positioning portion and the second contact portion come into contact with each other. It arranges in. According to this, when a lens is assembled | attached to a housing | casing, the structure which pushes a lens toward a 1st contact part is realizable.

  In the above-described embodiment, the configuration in which the second positioning portions 120, 220, and 320 overlap with the lens portion 54A when viewed from the sub-scanning direction is illustrated (see FIGS. 6 to 8). It is not a thing. That is, if the second positioning portion is provided at a position displaced in the sub-scanning direction with respect to the pair of long surfaces (a position that does not overlap with the pair of long surfaces when viewed from the optical axis direction), the arrangement position Is not particularly limited. For example, the second positioning portion may be provided at a portion (a position that does not overlap with the lens portion 54A when viewed from the sub-scanning direction) extended from the surface on the lens surface 54D side of the rib portion 54C toward the outside in the optical axis direction. .

  In the embodiment, the configuration in which the second positioning portions 120, 220, and 320 are provided in the central portion in the longitudinal direction of the fθ lens 54 (lens) is exemplified, but the present invention is not limited to this. You may provide in a part.

  In the embodiment, the configuration in which the first positioning portion 110 is provided on the surface on the lens surface 54E side among the surfaces facing the optical axis direction of the flange portion 54B is exemplified, but the present invention is not limited thereto, and the lens surface 54D is not limited thereto. It may be provided on the side surface. Further, the shape of the first positioning portion is not limited to a cylindrical shape, and may be, for example, a triangular prism shape or a quadrangular prism shape. Furthermore, the first positioning portion is not limited to the protruding column shape, and may be, for example, the surface of the flange portion that faces the optical axis direction (a surface orthogonal to the optical axis direction) itself.

  In the above-described embodiment, the configuration in which the leaf spring portion 150 is provided in the housing 50 is illustrated. However, the configuration is not limited thereto. For example, the leaf spring portion 150 may not be provided. Moreover, you may form the 1st contact part in the clip shape which clamps a lens (flange part).

  In the embodiment, the semiconductor laser light source 51A is exemplified as the light source, but the present invention is not limited to this. For example, a solid laser light source such as a YAG laser may be adopted.

  In the above-described embodiment, the polygon mirror 52 that deflects and scans the laser light (light beam) by rotating the reflecting surface is illustrated as the deflector. However, the present invention is not limited to this, and for example, the reflecting surface swings. A vibrating mirror that deflects and scans the light beam may be employed.

  In the embodiment, the fθ lens 54 is exemplified as the lens, but the lens is not limited to this. That is, the lens of the present invention is not particularly limited as long as it is a lens supported by a housing, and may be, for example, a cylindrical lens.

  In the above-described embodiment, the fθ lens 54 (lens), which is the lens surfaces 54D and 54E, both of which have lens characteristics, of the pair of long surfaces of the lens portion 54A is exemplified, but the present invention is not limited thereto. Is not to be done. In other words, it is sufficient that at least one of the long pair of long surfaces has lens characteristics. For example, one of the long long surfaces may be a lens surface having lens characteristics, and the other may be a flat surface having no lens characteristics.

  In the above-described embodiment, the laser printer 1 is exemplified as the image forming apparatus. However, the image forming apparatus is not limited thereto, and may be a copying machine, a multifunction machine, or the like. In the above embodiment, the optical scanning device of the present invention is applied to the image forming apparatus (laser printer 1). However, the present invention is not limited to this. For example, the optical scanning device may be applied to a measuring device or an inspection device. Good.

5 Optical Scanning Device 50 Housing 50A Base Frame 51 Light Source Device 51A Semiconductor Laser Light Source 52 Polygon Mirror 54 fθ Lens 54A Lens Portion 54B Flange Portion 54C Rib Portion 54D Lens Surface 54E Lens Surface 110 First Positioning Portion 120 Second Positioning Portion 121 Inclination Surface 122 Inclined surface 130 1st contact part 140 2nd contact part 220 2nd positioning part 221 Groove 240 2nd contact part 320 2nd positioning part 340 2nd contact part C1 contact C2 contact D1 space | interval D2 Diameter

Claims (5)

A light source; a deflector that deflects and scans a light beam from the light source in a main scanning direction; a lens through which the light beam deflected and scanned by the deflector passes; and a housing that supports the lens. An optical scanning device,
The lens has a pair of elongated surfaces facing each other, at least one of which is a lens surface having lens characteristics, and flange portions provided at both ends in the longitudinal direction of the lens portion And a first positioning portion provided on one of the surfaces of the flange portion facing the optical axis direction, and a second positioning portion provided at a position shifted in the sub-scanning direction with respect to the pair of long surfaces. Have
The casing is provided between the two first contact portions that contact the first positioning portion and the two first contact portions in the longitudinal direction of the lens, A second abutting portion that abuts at two locations,
In the second positioning portion and the second contact portion, the two contact points sandwich the second positioning portion or the second contact portion in the longitudinal direction, and the lens is used as the first contact portion. An optical scanning device, wherein one of the optical scanning devices is in contact with the other while pressing the other.   The optical scanning device according to claim 1, wherein the second positioning portion is provided at a central portion in a longitudinal direction of the lens.   One of the second positioning portion and the second contact portion has two inclined surfaces that are tapered toward the optical axis direction, and the other has two inclined surfaces, and the two inclined surfaces are provided. The optical scanning device according to claim 1, wherein the optical scanning device is in contact with the surface therebetween.   One of the second positioning portion and the second abutting portion has a V-shaped groove that tapers in the optical axis direction, and the other enters the groove and contacts at two locations. The optical scanning device according to claim 1, wherein the optical scanning device is in contact with the optical scanning device.   One of the second positioning portion and the second contact portion has a cylindrical shape, and the other has a cylindrical shape, and two are provided, and the distance between them is smaller than the diameter of the one. The optical scanning device according to claim 1 or 2.

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