JP5499003B2 - Optical scanning device and image forming apparatus using the same - Google Patents

Description

  The present invention relates to an optical scanning device using a multi-beam type light source and an image forming apparatus using the same.

  Laser printers, copiers, and the like are equipped with an optical scanning device that scans and exposes the peripheral surface (scanned surface) of a photosensitive drum with laser light to form an electrostatic latent image on the peripheral surface. The optical scanning device is provided with a BD (Beam Detect) sensor into which a part of the laser beam is incident in order to synchronize the writing start timing to the photosensitive drum. Usually, the laser light source that emits the laser light is mounted on a circuit board (APC board) on which an APC (Auto Power Control) circuit is mounted, and the BD sensor is mounted on a circuit board different from the APC board. Yes.

  Patent Document 1 discloses an optical scanning device in which a laser light source and a BD sensor are mounted on the same circuit board in a single beam type optical scanning device. According to this apparatus, it is possible to reduce the number of circuit boards used and to share both drive circuits.

  Patent Document 2 discloses an optical scanning device in which a multi-beam laser light source and a BD sensor are mounted on the same circuit board in a multi-beam optical scanning device. In the multi-beam method, it is necessary to adjust the beam pitch in the sub-scanning direction on the photosensitive drum according to the set resolution (dpi) of the image. This adjustment is performed by slightly rotating the laser light source around the optical axis. However, when the laser light source and the BD sensor are mounted on the same circuit board, the position of the BD sensor changes with the rotation around the optical axis, causing a problem that the laser beam does not enter the light receiving surface of the BD sensor. . In the apparatus of Patent Document 2, an optical element (anamorphic lens) that converts a spot of a detection light beam toward the BD sensor into a spot that is long in the sub-scanning direction is used. Even if the position of the BD sensor is shifted by the rotation, The BD sensor can detect the detection light beam.

Japanese Patent Laid-Open No. 2-118612 JP 2002-189180 A

  However, according to the method disclosed in Patent Document 2, a special optical element for shaping the detection laser beam incident on the BD sensor is separately required. This leads to an increase in the number of parts and an increase in cost.

  The present invention has been made in view of the above circumstances, and employs a configuration in which a light source and a sensor for synchronizing writing timing are mounted on the same circuit board in a multi-beam optical scanning device. It is another object of the present invention to provide an optical scanning device that does not require a special optical element and an image forming apparatus using the same.

  An optical scanning device according to one aspect of the present invention includes a light source that includes a plurality of light emitting points that emit a light beam, a light source that supplies power to the light emitting unit, and a light source that reflects and deflects the light beam. A deflecting body to be scanned, an imaging optical system that forms an image on the scanning surface of the light beam that has been deflected and scanned, a housing that houses at least the deflecting body and the imaging optical system, and the deflection scanned By receiving a light beam and outputting a detection signal indicating the received light, a circuit board on which the light source and the synchronization sensor are mounted, and rotating the light emitting unit around its optical axis, Adjusting means for adjusting the interval on the surface to be scanned of light beams emitted from a plurality of light emitting points, and the light emitting portion is erected at a predetermined height on the circuit board by the lead portion. And said adjustment The stage includes a holding member that holds the light emitting unit fixedly, first fixing means for fixing the holding member to a first position of the housing in a state where the distance is adjusted, and fixing the holding member And a second fixing means for fixing the circuit board to the second position of the housing, and the circuit board and the holding member are connected by the lead part at a predetermined interval, and the lead part Is twisted according to the rotation around the optical axis of the light-emitting portion in accordance with the adjustment of the distance during the fixing by the second fixing means.

  According to this configuration, the holding member that fixedly holds the light emitting portion of the light source is fixed to the first position of the housing by the first fixing means, and the circuit board is fixed to the second position of the housing by the second fixing means. . That is, the substrate and the light emitting unit are separately fixed at different positions on the housing. For this reason, even if the light emitting portion is rotated around the optical axis together with the holding member, the rotation can be absorbed by twisting of the lead portion. Therefore, after the interval is adjusted and the holding member is fixed to the housing by the first fixing means, the synchronization sensor and the incident light beam are aligned to align the circuit board with the second housing. The position can be fixed.

  In the above configuration, the holding member is a bracket having a holder portion into which the light emitting portion is press-fitted, and the first fixing means includes a plurality of first screw holes provided in the bracket and the first screw. Preferably, a plurality of first screws for attaching the bracket to the first position of the housing through a hole are included.

  According to this configuration, the first fixing means is configured by the plurality of first screw holes provided in the bracket and the first screws inserted through the first screw holes, so that the bracket is adjusted for adjusting the distance. A simple adjustment method in which the first screw is fastened after being rotated can be realized. Therefore, the rotation operation around the optical axis of the light emitting unit in the adjustment of the interval by the adjusting means can be easily performed.

  In this case, the circuit board is disposed so as to overlap the bracket, and the circuit board has a notch portion that exposes the first screw hole when viewed in the direction in which the circuit board and the bracket overlap. It is desirable to be provided.

  According to this structure, since the 1st screw hole provided in the said bracket is exposed through the notch part of the said circuit board, the workability | operativity of the user who adjusts the said space | interval can be improved.

  In the above configuration, the second fixing means includes a plurality of second screw holes provided in the circuit board, and a plurality of second screws for attaching the circuit board to the second position of the housing through the second screw holes. It is desirable that at least one of the second screw holes is disposed in the vicinity of the mounting position of the synchronous sensor.

  According to this configuration, since the vicinity of the mounting position of the synchronous sensor is set to the fixed position by the second screw, it is possible to make it difficult for the synchronous sensor to be affected by, for example, vibration caused by driving the deflecting body.

  An image forming apparatus according to another aspect of the present invention includes the optical scanning device described above, and an image carrier including an electrostatic latent image carrying surface serving as the scanned surface.

  According to the present invention, while adopting a configuration in which a light source and a synchronization sensor for synchronizing writing timing are mounted on the same circuit board, an optical axis of a light emitting unit without requiring a special optical element Both the rotation adjustment and the incidence of the detected light beam to the synchronous sensor can be ensured. Accordingly, it is possible to reduce the number of parts and the cost of the optical scanning device and the image forming apparatus provided with the same.

1 is a cross-sectional view illustrating an internal configuration of an image forming apparatus according to an embodiment of the present invention. It is a perspective view which shows typically the internal structure of an optical scanning device. It is a typical perspective view for demonstrating the exposure aspect of the photoreceptor drum by a multi-beam system. It is a perspective view which shows the light emission part of a multi-beam laser light source. It is a top view of the front view of a bracket and a circuit board. It is a top view in the rear view of a bracket and a circuit board. It is a perspective view which shows the attachment state of the bracket and BD sensor to a circuit board. It is a perspective view which shows the housing of an optical scanning device, the bracket mounted in the housing, and a circuit board.

  Hereinafter, an optical scanning device according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view schematically showing a configuration of an image forming apparatus 1 on which an optical scanning device 11 according to an embodiment of the present invention is mounted. In this embodiment, a printer is exemplified as the image forming apparatus. However, the present invention is also applicable to a copying machine, a facsimile machine, and a multifunction machine having various functions. The image forming apparatus 1 includes an optical scanning device 11, a developing device 12, a charger 13, a photosensitive drum 14 (image carrier), a transfer roller 15, a fixing device 16, and a paper feed cassette 17.

  The photosensitive drum 14 is a cylindrical member, and an electrostatic latent image and a toner image are formed on the peripheral surface thereof. The photosensitive drum 14 receives a driving force from a motor (not shown) and is rotated in the clockwise direction in FIG. The charger 13 charges the surface of the photosensitive drum 14 substantially uniformly.

  The optical scanning device 11 is a multi-beam optical scanning device, and includes an imaging optical system such as a multi-beam laser light source, a deflector, a scanning lens, and an optical element, and is substantially uniformly charged by a charger 13. An electrostatic latent image of the image data is formed by irradiating the peripheral surface (scanned surface) of the photosensitive drum 14 with laser light corresponding to the image data. The optical scanning device 11 will be described in detail later.

  The developing device 12 supplies toner to the peripheral surface of the photosensitive drum 14 on which the electrostatic latent image is formed, thereby forming a toner image. The developing device 12 includes a developing roller that carries toner and a screw that stirs and conveys the toner. The toner image formed on the photosensitive drum 14 is transferred from the sheet feeding cassette 17 to the recording paper conveyed through the conveyance path P. The developing device 12 is supplied with toner from a toner container (not shown).

  A transfer roller 15 is disposed below the photosensitive drum 14 so as to face each other, and a transfer nip portion is formed by both. The transfer roller 15 is made of a conductive rubber material or the like and is given a transfer bias to transfer the toner image formed on the photosensitive drum 14 onto the recording paper.

  The fixing device 16 includes a fixing roller 160 having a built-in heater and a pressure roller 161 provided at a position facing the fixing roller 160, and is formed on the recording paper by heating and conveying the recording paper on which the toner image is formed. The toner image is fixed.

  Next, an image forming operation of the image forming apparatus 1 will be briefly described. First, the surface of the photosensitive drum 14 is charged almost uniformly by the charger 13. The peripheral surface of the charged photosensitive drum 14 is exposed by the optical scanning device 11, and an electrostatic latent image of an image formed on the recording paper is formed on the surface of the photosensitive drum 14. The electrostatic latent image is made visible as a toner image by supplying toner from the developing device 12 to the peripheral surface of the photosensitive drum 14. On the other hand, the recording paper is fed from the paper feed cassette 17 to the transport path P. The toner image is transferred to the recording paper when the recording paper passes through the nip portion between the transfer roller 15 and the photosensitive drum 14. After this transfer operation is performed, the recording paper is conveyed to the fixing device 16 and the toner image is fixed to the recording paper.

  FIG. 2 is a perspective view schematically showing the internal configuration of the optical scanning device 11. The optical scanning device 11 sensitizes a housing 20, a laser light source 30 (light source) accommodated in the housing 20, a deflector 40 that reflects and scans a light beam emitted from the laser light source 30, and the light beam that has been deflected and scanned. An imaging optical system that forms an image on the peripheral surface of the body drum 14 and first and second BD (Beam Detect) sensors 6A and 6B (synchronous sensors) are included. The imaging optical system includes a collimator lens 51, a cylindrical lens 52, a first scanning lens 53, a second scanning lens 54, a mirror 55, and first and second condenser lenses 56A and 56B.

  The laser light source 30 includes a light emitting unit 30A that has a plurality of light emitting points and emits a multi-beam laser, and a lead unit 35 for supplying power to the light emitting unit 30A. FIG. 3 is a schematic perspective view for explaining an exposure mode of the photosensitive drum 14 by the multi-beam method, and FIG. 4 is a perspective view showing the light emitting unit 30A. The light emitting unit 30A includes a cylindrical plug member, and four laser diodes (LDs) 31, 32, 33, and 34 (light emitting points) arranged in a line at regular intervals are arranged on the tip surface F thereof. A monolithic multi-laser diode. The four LD31 to LD34 are arranged on a line having an inclination angle with respect to each of the main scanning direction and the sub-scanning direction. In the present embodiment, a monolithic multi-laser diode having four LDs will be described as an example. However, any monolithic multi-laser diode in which two or more LDs are arranged on the same chip may be used.

  The collimator lens 51 is a lens that converts a diffused light emitted from the laser light source 30 into parallel light. The cylindrical lens 52 is a lens that converts the parallel light beam into linear light that is long in the main scanning direction and forms an image on the deflecting body 40 (polygon mirror 41).

  The deflecting body 40 reflects and scans the light beam formed by the cylindrical lens 5 and includes a polygon mirror 41 and a polygon motor 42. The polygon mirror 41 rotates at a predetermined speed in the direction of arrow R in the figure, and deflects the light beam so that the light beam is scanned in the longitudinal direction (main scanning direction) of the photosensitive drum 14. The polygon motor 42 generates a rotational force that rotates the polygon mirror 41 at a predetermined speed. A polygon mirror 41 is connected to the rotation shaft 43 of the polygon motor 42, and the polygon mirror 41 rotates around the rotation shaft 43. Note that a MEMS (Micro Electro Mechanical Systems) mirror may be used as the deflecting body 40.

  The first scanning lens 53 and the second scanning lens 54 are lenses having fθ characteristics and are provided with a lens surface (rotationally asymmetric refracting surface) made of a special toric surface. These scanning lenses 53 and 54 are arranged to face each other on the optical axis from the polygon mirror 41 toward the circumferential surface of the photosensitive drum 14. The first and second scanning lenses 53 and 54 collect the deflected light beam reflected by the polygon mirror 41 and form an image on the peripheral surface of the photosensitive drum 14.

  The mirror 55 reflects the deflected light beam output from the first scanning lens 53 and the second scanning lens 54 toward an opening (not shown) provided in the housing 20 and irradiates the photosensitive drum 14. The first condensing lens 56A and the second condensing lens 56B are installed on the optical path outside the effective scanning area of the peripheral surface of the photosensitive drum 14 by the polygon mirror 41, and the deflected light flux is respectively sent to the first BD sensor 6A and It is a lens that forms an image on the second BD sensor 6B.

  The first BD sensor 6 </ b> A and the second BD sensor 6 </ b> B detect the deflected light beam in order to synchronize the writing timing that is the timing for starting the irradiation of the deflected light beam on the peripheral surface of the photosensitive drum 14 for one main scanning line. . The first BD sensor 6A is disposed on the scanning start side of the main scanning line, and the second BD sensor 6B is disposed on the scanning end side of the main scanning line. The first and second BD sensors 6A and 6B are composed of photodiodes or the like, and output a high level signal when no light beam is detected, and output a low level signal while the light beam passes through the light receiving surface. Output.

  As shown in FIG. 3, four laser beams LB- 1 to LB- 4 are emitted from the LD 31 to LD 34 of the laser light source 30 toward the polygon mirror 41. In FIG. 3, the description of the imaging optical system is omitted. The polygon mirror 41 is rotated at high speed in the direction of arrow R around the axis of the rotation shaft 43 by the polygon motor 42. The polygon mirror 41 has six reflecting mirror surfaces 41A, 41B, 41C, 41D, 41E, and 41F. At a certain timing, the four laser beams LB-1 to LB-4 are applied to one reflecting mirror surface (the reflecting mirror surface 41B in FIG. 3), and are refracted and reflected by the reflecting mirror surface 41B in the circumferential direction of the photosensitive drum 14. Is done. With the rotation of the polygon mirror 41, the four laser beams LB-1 to LB-4 scan the peripheral surface of the photosensitive drum 14 along the main scanning direction D2. As a result, four scanning lines SL are drawn on the peripheral surface of the photosensitive drum 14. Since the laser beams LB-1 to LB-4 are modulated according to the image data, an electrostatic latent image corresponding to the image data is formed on the circumferential surface of the photosensitive drum 14.

  Here, the four laser beams LB-1 to LB-4 are laser beams LB-1, LB-2, LB-3, and LB- in the sub-scanning direction D1 (the rotation direction of the photosensitive drum 14 in FIG. 3). In a state of being arranged in the order of 4, four scanning lines SL are drawn in the main scanning direction D2. This is because, as shown in FIG. 4, the four LD31 to LD34 are arranged in a straight line at regular intervals. Therefore, the beam pitch in the sub-scanning direction of the laser beams LB-1 to LB-4, that is, the resolution (dpi) of the image to be drawn depends on the arrangement pitch of the four LD31 to LD34.

  The beam pitch can be adjusted by rotating the light emitting unit 30A around the core of the holder member. Specifically, the arrangement pitch of the four LD31 to LD34 is apparent by rotating the light emitting unit 30A in the direction of the arrow in the drawing with the normal G passing through the center O of the tip surface F of the light emitting unit 30A as the rotation axis. The top can be changed. That is, when the light emitting unit 30A is rotated clockwise around the axis of the normal G, the beam pitch in the sub-scanning direction is decreased, and conversely, when rotated in the counterclockwise direction, the beam pitch in the sub-scanning direction is increased. . Therefore, the beam pitch according to the set resolution of the image can be obtained by adjusting the rotation of the light emitting unit 30A.

  In FIG. 2, for simplicity of illustration, the laser light source 30 and the first and second BD sensors 6 </ b> A and 6 </ b> B are drawn apart from each other, but in this embodiment, the laser light source 30 and the first and second BD sensors 6 </ b> A are drawn. 6B (hereinafter referred to as BD sensor 6) is mounted on the same circuit board 70. 5 to 7 are views showing a state in which the laser light source 30 (bracket 36) and the BD sensor 6 are attached to the circuit board 70. FIG. 5 is a plan view in front view, and FIG. 6 is a plan view in rear view. FIG. 7 shows a perspective view of the circuit board 70 and the bracket 36 as viewed from the side in the stacking direction.

  The circuit board 70 is mounted with circuit components (not shown) such as a driving circuit for the laser light source 30 and an APC (Automatic Power Control) circuit for controlling the amount of light emitted from the LD 31 to LD 34. In this embodiment, the circuit board 70 is a bracket 36. This is a substrate on which the held laser light source 30 and the BD sensor 6 are mounted. The circuit board 70 has a rectangular shape.

  First and second cutout portions 701 and 702 are provided on a pair of long sides of the circuit board 70, respectively. The first notch 701 is provided in the vicinity of the end portion of the upper long side and has a substantially right-angled triangular notch shape. The second notch 702 is provided near the center of the lower long side, and has a substantially isosceles triangular notch shape. Further, in the vicinity of each long side of the circuit board 70, a first board screw hole 703 and a second board screw hole 704 (part of the second fixing means / second screw hole) are formed, respectively. The first board screw hole 703 and the second board screw hole 704 are disposed at substantially diagonal positions of the circuit board 70 with the mounting position of the laser light source 30 interposed therebetween.

  The BD sensor 6 is mounted at a position close to one short side of the circuit board 70. The second substrate screw hole 704 is drilled at a position near the short side where the BD sensor 6 is close. Accordingly, the distance L between the BD sensor 6 and the second substrate screw hole 704 is relatively short, and the BD sensor 6 is mounted in the vicinity of the second substrate screw hole 704.

  The bracket 36 (a holding member / a part of the adjusting means) is a member that holds the laser light source 30 in a fixed manner, and is a rectangular flat plate member having a first end 361 and a second end 362 in the longitudinal direction. is there. A holder portion 36H into which a cylindrical plug member in the light emitting portion 30A of the laser light source 30 is inserted is drilled at the center position of the bracket 36. The inner diameter of the holder portion 36H is slightly smaller than the outer diameter of the plug member of the light emitting portion 30A, and the light emitting portion 30A is press-fitted into the holder portion 36H. By this press-fitting, the light emitting unit 30A and the bracket 36 are integrated. A first holding hole 363 and a second holding hole 364 (part of the first fixing means / first screw hole) are formed in the vicinity of the first end 361 and the second end 362 of the bracket 36, respectively. ing.

  The laser light source 30 is mounted on the circuit board 70 in such a manner that the lower end of the lead part 35 is inserted into a mount hole provided in the circuit board 70 and soldered at the insertion part. In other words, the circuit board 70 and the bracket 36 are connected only by the lead portion 35. The lead part 35 has a predetermined length. As shown in FIG. 7, the light emitting part 30A stands on the circuit board 70 in a state where a predetermined interval H is interposed between the circuit board 70 and the bracket 36. It is installed. The predetermined interval H is a length that allows the lead portion 35 to be twisted when adjusting the rotation of the light emitting portion 30A around the optical axis.

  FIG. 8 is a perspective view showing a state in which the assembly of the bracket 36 and the circuit board 70 is mounted on the housing 20 of the optical scanning device 11. The bracket 36 and the circuit board 70 are separately fixed to the mounting plate 21 that constitutes a part of the side wall of the housing 20. The bracket 36 is fixed to a predetermined position (first position) of the mounting plate 21 by a first holding screw 371 and a second holding screw 372 (part of the first fixing means / first screw). The circuit board 70 is fixed to a predetermined position (second position) of the mounting plate 21 by a first board screw 71 and a second board screw 72 (part of the second fixing means / second screw).

  Specifically, the first holding screw 371 is inserted into the first holding hole 363, and the second holding screw 372 is inserted into the second holding hole 364, and fastened to the screw holes provided at the first position of the mounting plate 21, respectively. As a result, the bracket 36 is fixed to the mounting plate 21 (housing 20). On the other hand, the first board screw 71 is inserted into the first board screw hole 703, and the second board screw 72 is inserted into the second board screw hole 704, and fastened to the screw holes provided at the second positions of the mounting plate 21. As a result, the circuit board 70 is fixed to the mounting plate 21 (housing 20).

  Here, both are attached to the housing 20 in such a manner that the circuit board 70 covers the bracket 36. That is, it is fixed to the mounting plate 21 in the state shown in FIG. The bracket 36 is mounted obliquely with respect to the circuit board 70, and the first end of the bracket 36 is viewed from the first notch 701 of the circuit board 70 when viewed in the direction in which the circuit board 70 and the bracket 36 overlap. A part of the part 361 is mounted so that a part of the second end part 362 is exposed from the second notch part 701. Accordingly, even when the bracket 36 rotates about the lead portion 35 as a rotation axis, and particularly when the bracket 36 rotates counterclockwise in FIG. 6, the first holding hole 363 and the second holding hole 364 are not cut off. It is exposed through the notch 701 and the second notch 702. Therefore, the fastening workability of the first holding screw 371 and the second holding screw 372 by the user can be improved.

  The BD sensor 6 is mounted in the vicinity of the second substrate screw hole 704. That is, the vicinity of the mounting position of the BD sensor 6 is a fixing position by the second substrate screw 72. For this reason, it is possible to make it difficult for the BD sensor 6 to be affected by vibration or the like caused by the rotational driving of the polygon mirror 41.

  Next, a procedure for fixing the assembly of the bracket 36 and the circuit board 70 to the housing 20 with the rotation adjustment of the light emitting unit 30A of the laser light source 30 will be described. First, the operator adjusts the beam pitch in the sub-scanning direction of the laser beams LB-1 to LB-4 emitted from the laser light source 30 using a jig (not shown). The jig is used to press and hold the bracket 36 against a predetermined contact surface of the housing 20 so that the bracket 36 faces the housing 20.

  In a state where the bracket 36 is held by the jig, the operator rotates the bracket 36 so that the light emitting unit 30A is appropriately rotated around the axis of the optical axis (normal line G). In this rotation process, a position where the beam pitch in the sub-scanning direction matches the specified resolution (dpi) is detected. After finishing the rotation adjustment of the light emitting unit 30A, the operator fixes the bracket 36 to the mounting plate 21 of the housing 20 with the first holding screw 371 and the second holding screw 372 (the first fixing member is held by the first fixing means). Fixed to 1 position). At this stage, the circuit board 70 itself is not directly fixed to the mounting plate 21 but is indirectly held by the mounting plate 21 via the lead portion 35. In addition, since the lead portion 35 has a length such that the predetermined distance H exists between the circuit board 70 and the bracket 36, the circuit board 70 can move to some extent by deformation (twisting) of the lead portion 35. It is.

  Subsequently, the operator positions the circuit board 70 so that the BD sensor 6 is disposed at a predetermined position. At this time, the lead portion 35 is twisted according to the rotation state of the bracket 36, that is, the rotation state around the optical axis of the light emitting portion 30A. With the BD sensor 6 aligned, the operator fixes the circuit board 70 to the mounting plate 21 of the housing 20 with the first board screw 71 and the second board screw 72 (circuit by the second fixing means). Fixing the substrate to the second position).

  As described above, according to the present embodiment, even when the light emitting unit 30 </ b> A is rotated around the optical axis together with the bracket 36, the rotation is absorbed by the twist of the lead unit 35. For this reason, after adjusting the beam pitch in the sub-scanning direction and fixing the bracket 36 to the housing 20, the BD sensor 6 and the incident light beam are aligned to fix the circuit board 70 to the housing 20. Can be made. Accordingly, while adopting a configuration in which the laser light source 30 and the BD sensor 6 are mounted on the same circuit board 70, the adjustment of the light emitting unit 30A around the optical axis and the BD sensor 6 are possible without requiring a special optical element. Both of the incident detection light beams can be ensured. Therefore, it is possible to reduce the number of parts and the cost of the optical scanning device 11 and the image forming apparatus 1 provided with the same.

DESCRIPTION OF SYMBOLS 1 Image forming apparatus 11 Optical scanning apparatus 14 Photosensitive drum (Image carrier)
30 Laser light source
31, 32, 33, 34 Laser diode (multiple emission points)
35 Lead part 36 Bracket (holding member)
363, 364 First and second holding holes (part of first fixing means / first screw hole)
36H Holder portions 371, 372 First and second holding screws (part of first fixing means / first screw)
40 Deflector 51 Collimator Lens 52 Cylindrical Lenses 53 and 54 First and Second Scan Lenses (Imaging Optical System)
55 Mirror (imaging optical system)
6A, 6B First and second BD sensors (synchronous sensors)
70 circuit boards 71, 72 first and second board screws (part of second fixing means / second screws)
701, 702 First and second cutout portions 703, 704 First and second substrate screw holes (part of second fixing means / second screw holes)

Claims (5)

A light source including a light emitting unit having a plurality of light emitting points that emit a light beam, and a lead unit for supplying power to the light emitting unit;
A deflector that reflects and deflects the luminous flux;
An imaging optical system that forms an image of the deflected and scanned light beam on a surface to be scanned;
A housing that houses at least the deflector and the imaging optical system;
A synchronous sensor that receives the deflected and scanned light beam and outputs a detection signal indicating the received light;
A circuit board on which the light source and the synchronization sensor are mounted;
Adjusting the light emitting unit by rotating the light emitting unit about its optical axis, thereby adjusting the interval on the scanned surface of the light beams emitted from the plurality of light emitting points;
The light emitting part is erected at a predetermined height on the circuit board by the lead part,
The adjusting means includes a holding member that fixedly holds the light emitting unit, a first fixing means that fixes the holding member to a first position of the housing in a state where the distance is adjusted, and the holding member Second fixing means for fixing the circuit board to a second position of the housing after fixing
The circuit board and the holding member are connected by the lead portion at a predetermined interval,
The optical scanning device, wherein the lead portion is twisted according to the rotation around the optical axis of the light emitting portion in accordance with the adjustment of the interval during the fixing by the second fixing means. The optical scanning device according to claim 1,
The holding member is a bracket having a holder portion into which the light emitting portion is press-fitted,
The first scanning means includes a plurality of first screw holes provided in the bracket, and a plurality of first screws for attaching the bracket to the first position of the housing through the first screw holes. apparatus. The optical scanning device according to claim 2,
The circuit board is arranged in a manner to overlap the bracket,
The optical scanning device, wherein the circuit board is provided with a notch for exposing the first screw hole when viewed in a direction in which the circuit board and the bracket overlap. The optical scanning device according to claim 1,
The second fixing means includes a plurality of second screw holes provided in the circuit board, and a plurality of second screws for attaching the circuit board to the second position of the housing through the second screw holes,
The optical scanning device, wherein at least one of the second screw holes is disposed in the vicinity of the mounting position of the synchronous sensor. An optical scanning device according to any one of claims 1 to 4,
An image carrier having an electrostatic latent image carrying surface serving as the scanned surface;
An image forming apparatus.

Images