JP2009119718A - Optical print head and image forming apparatus equipped with the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical print head which can make a focus adjusting mechanism thin. <P>SOLUTION: This optical print head is equipped with an LED array 3, a lens array 6, and the focus adjusting mechanism 10 which carries out focusing by adjusting a position in a Z direction of the lens array 6. The focus adjusting mechanism 10 includes at least a movable member 11 arranged movably in the Z direction in a state of coupling with the lens array 6, an adjusting belt 12 which adjusts a movement amount in the Z direction of the movable member 11, and a gear 13 which transmits a driving force from the adjusting belt 12 to the movable member 11. The driving force is transmitted from the adjusting belt 12 to the movable member 11 via the gear 13 by moving the adjusting belt 12 in a Y direction, whereby the movable member 11 is moved in the Z direction. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an optical print head and an image forming apparatus including the same.

  Conventionally, an optical print head capable of selectively emitting light from a plurality of light emitting units arranged in a line is known, and an image is used as an exposure unit for forming an electrostatic latent image on a photoreceptor. It is mounted on a forming apparatus (see, for example, Patent Document 1). Conventionally, an optical print head in which an LED (light emitting diode) functions as a light emitting unit in the above-described configuration is also known.

  FIG. 12 is a diagram schematically showing an example of the structure of a conventional optical print head. Referring to FIG. 12, as a conventional optical print head structure, a plurality of LED array chips 102 are mounted on a predetermined circuit board 101. Each of the plurality of LED array chips 102 includes a predetermined number of LEDs 102a arranged in a line.

  In the conventional optical print head shown in FIG. 12, the light L emitted from the LED array chip 102 becomes diffused light. Therefore, the lens array 103 for condensing the light and forming an image on the photoconductor 110. Is provided. The lens array 103 includes a plurality of lenses 103a arranged in a line, and is arranged at a predetermined interval from the LED array chip 102 in the Z direction.

In the conventional configuration described above, it is necessary to provide a focus adjustment mechanism unit for adjusting the position of the lens array 103 in the Z direction in order to suppress a decrease in print quality due to the shift of the focus position. Although not shown, the focus adjustment mechanism unit includes at least an adjustment member coupled to the lens array 103, and adjusts the position of the lens array 103 in the Z direction by moving the adjustment member in the Z direction. It is configured as follows.
JP 2007-7933 A

  In the conventional configuration described above, when the lens array 103 including a plurality of lenses 103a having a relatively short focal length is used, the height of the structure including the lens array 103 in the Z direction, the lens array 103, the photoconductor 110, and the like. The interval in the Z direction becomes smaller. In this case, it is necessary to reduce the height in the Z direction of the focus adjustment mechanism (not shown).

  However, the conventional focus adjustment mechanism (not shown) described above is configured to adjust the position of the lens array 103 in the Z direction by moving an adjustment member connected to the lens array 103 in the Z direction. Therefore, if the height in the Z direction is reduced, the adjustment width when adjusting the position of the lens array 103 in the Z direction is narrowed. That is, the conventional focus adjustment mechanism has a problem that it is difficult to reduce the thickness by reducing the height in the Z direction.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide an optical print head capable of reducing the thickness of the focus adjustment mechanism and an image forming apparatus including the same. Is to provide.

  In order to achieve the above object, an optical print head according to a first aspect of the present invention is mounted on a predetermined surface of a base and includes a light emitting element array including a plurality of light emitting elements that generate light, and a light emitting element array. An imaging element that includes a plurality of imaging elements that are arranged at a predetermined interval in a first direction perpendicular to a predetermined surface of the table, and that focus light from the light emitting element array to form an image on an image carrier An array and a focus adjustment mechanism that is provided on a predetermined surface of the base and performs focusing by adjusting the position of the imaging element array in the first direction. The focus adjustment mechanism unit is a movable member that is connected to the imaging element array so as to be movable in the first direction, and an adjustment member that adjusts the amount of movement of the movable member in the first direction. And at least a transmission member that transmits power from the adjustment member to the movable member, and is movable from the adjustment member via the transmission member by moving the adjustment member in a second direction horizontal to a predetermined surface of the base. Power is transmitted to the member, and the movable member is configured to move in the first direction.

  In the optical print head according to the first aspect, the adjustment member is moved in the second direction to adjust the position of the imaging element array in the first direction by using the focus adjustment mechanism as described above. Can be performed. That is, the adjustment width when adjusting the position of the imaging element array in the first direction is determined by the movement width of the adjustment member in the second direction. Accordingly, when the height of the focus adjustment mechanism portion in the first direction is limited, even if the height of the focus adjustment mechanism portion in the first direction is reduced, the movement width of the adjustment member in the second direction is reduced. Is not affected, the adjustment width at the time of adjusting the position of the imaging element array in the first direction is not narrowed. As a result, the focus adjustment mechanism can be thinned without narrowing the adjustment width when adjusting the position of the imaging element array in the first direction.

  In the optical print head according to the first aspect, preferably, the transmission member rotates as the adjustment member moves in the second direction, and the rotation axis extends along the first direction. The movable member is provided with a male screw extending along the first direction, and a female screw portion into which the male screw of the movable member is screwed is formed at the rotation center of the transmission member. . If comprised in this way, the position of the imaging element array connected to the movable member in the first direction can be adjusted by adjusting the screwing amount of the male screw of the movable member with respect to the female screw portion of the transmission member. Since the transmission member rotates as the adjustment member moves in the second direction, the position of the imaging element array in the first direction can be easily adjusted by moving the adjustment member in the second direction. It becomes possible to adjust.

  In this case, preferably, the transmission member is a gear that is rotatably installed around a rotation axis extending along the first direction, and the adjustment member includes a plurality of gears arranged along the second direction. A tooth portion is formed, and a gear meshes with the tooth portion of the adjusting member. If comprised in this way, a transmission member (gear) can be easily rotated centering | focusing on the rotating shaft extended along a 1st direction by moving an adjustment member to a 2nd direction.

  In the optical print head according to the first aspect, preferably, the focus adjustment mechanism unit further includes a base member fixed to the base, and the movable member is provided with a guide pin extending along the first direction. In addition, a guide hole into which a guide pin of the movable member is inserted is formed in the base member. If comprised in this way, the guide pin of a movable member will be in the state inserted in the guide hole of the base member, and the shakiness of the movable member at the time of moving a movable member to a 1st direction is suppressed. be able to. Thereby, the movement of the movable member in the first direction can be performed smoothly.

  In this case, preferably, the focus adjustment mechanism unit further includes a pressing member that presses the guide pin of the movable member in the second direction. According to this structure, after performing focusing by adjusting the position of the imaging element array connected to the movable member in the first direction, the guide pin of the movable member is moved in the second direction by the pressing member. By pressing, the movable member (imaging element array) can be fixed so as not to move. Accordingly, it is possible to suppress the occurrence of inconvenience that the focus is shifted despite the fact that the focusing is performed.

  In the optical printhead according to the first aspect, the light emitting element may be a light emitting diode, and the light emitting element array may be a light emitting diode array including a plurality of light emitting diodes.

  An image forming apparatus according to a second aspect of the present invention is an image forming apparatus including the optical print head according to any one of claims 1 to 6. With this configuration, it is possible to easily obtain an image forming apparatus capable of reducing the thickness of the focus adjustment mechanism.

  As described above, according to the present invention, it is possible to easily obtain an optical print head capable of reducing the thickness of the focus adjustment mechanism and an image forming apparatus including the same.

  FIG. 1 is an overall perspective view of an optical print head according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view taken along line 100-100 in FIG. 3 is a plan view of an LED array (light emitting element array) of the optical print head according to the embodiment shown in FIG. 1, and FIG. 4 is a lens array of the optical print head according to the embodiment shown in FIG. It is a top view of an imaging element array. FIG. 5 is a diagram for explaining the function of the lens array (imaging element array) shown in FIG. FIG. 6 is a perspective view of the focus adjustment mechanism of the optical print head according to the embodiment shown in FIG. 7 is a plan view of the focus adjustment mechanism portion shown in FIG. 6 when viewed from below, and FIG. 8 is a cross-sectional view taken along line 200-200 in FIG. FIG. 9 is an exploded perspective view of the focus adjustment mechanism shown in FIG. 10 is a perspective view of a movable member included in the focus adjustment mechanism shown in FIG. 6, and FIG. 11 is a perspective view of a base member included in the focus adjustment mechanism shown in FIG. First, the structure of the optical print head according to the present embodiment will be described with reference to FIGS. Note that the optical print head of this embodiment is used in an image forming apparatus such as an electrophotographic printer.

  As the structure of the optical print head of this embodiment, as shown in FIGS. 1 and 2, a multilayer wiring board 2 is attached to a heat sink 1, and an LED array 3 is mounted on the multilayer wiring board 2. The heat sink 1 is an example of the “base” of the present invention, and the LED array 3 is an example of the “light emitting element array” of the present invention.

  The heat sink 1 has a smooth predetermined surface 1a formed in a rectangular shape when seen in a plan view. The LED array 3 mounted on the multilayer wiring board 2 is mounted on a predetermined surface 1 a of the heat sink 1. Thereby, it is possible to easily dissipate heat generated in the LED array 3.

  In addition, a plurality of fin portions 1b are formed on a portion (lower portion) opposite to the predetermined surface 1a of the heat sink 1 so as to protrude downward. The plurality of fin portions 1b of the heat sink 1 are formed in an elongated shape extending along the X direction (longitudinal direction of the predetermined surface 1a of the heat sink 1) and the Y direction (predetermined surface of the heat sink 1) orthogonal to the X direction. 1a in the short direction of 1a) and arranged at a predetermined interval. By using the heat sink 1 provided with a plurality of such fin portions 1b, the heat dissipation characteristics can be further improved.

  Further, at both ends in the X direction of the heat sink 1, screw holes 1c for screwing the heat sink 1 to a housing (not shown) of the image forming apparatus are formed one by one. The optical print head is fixed to the housing of the image forming apparatus by screwing the heat sink 1 to the housing of the image forming apparatus.

  The multilayer wiring board 2 is formed in a rectangular shape in which the X direction is the longitudinal direction (Y direction is the short direction) when viewed in plan. The multilayer wiring board 2 is placed on a predetermined surface 1a of the heat sink 1 so that screw holes 1c formed at both ends of the heat sink 1 are exposed. The multilayer wiring board 2 is screwed to the heat sink 1 with screws 8.

  As shown in FIGS. 2 and 3, the LED array 3 mounted on the multilayer wiring board 2 includes a plurality of LED array chips 3a arranged in a line in the X direction, and the plurality of LED arrays. Each of the chips 3a includes a predetermined number of LEDs 3b that generate light. The predetermined number of LEDs 3b included in each LED array chip 3a has a light emitting direction (a direction in which light having the highest luminance is emitted) in a Z direction (a direction perpendicular to the predetermined surface 1a of the heat sink 1). While being adjusted, they are arranged in a line at a predetermined density (for example, 600 dpi (dot per inch)) in the X direction. A predetermined number of LEDs 3 b included in each LED array chip 3 a are driven by a driver IC 4 mounted on the multilayer wiring board 2. The LED 3b is an example of the “light emitting element” in the present invention.

  Further, as shown in FIGS. 1 and 2, a cover member 5 screwed to the heat sink 1 by a screw 8 together with the multilayer wiring board 2 is provided on a predetermined surface 1 a of the heat sink 1. The cover member 5 is formed in a rectangular shape so that the X direction is the longitudinal direction (Y direction is the short direction) when viewed in plan, and the length of the cover member 5 in the X direction is a multilayer wiring. It is smaller than the length of the substrate 2 in the X direction. The cover member 5 covers a portion other than both end portions in the X direction of the multilayer wiring board 2.

  Further, the cover member 5 is formed with a concave portion 5a having an opening end on the multilayer wiring board 2 side. The LED array 3 and the driver IC 4 mounted on the multilayer wiring board 2 are covered with the recess 5a of the cover member 5 so that the surrounding space is substantially blocked from the outside. Thereby, it can suppress that a foreign material penetrate | invades on the optical path of the emitted light from LED array 3 in the vicinity of LED array 3. FIG. In addition, although not shown in figure, the recessed part 5a of the cover member 5 is formed in the elongate shape extended in a X direction seeing planarly.

  In addition, a slit 5 b for taking out the emitted light from the LED array 3 is formed in a portion of the cover member 5 that overlaps the LED array 3 when seen in a plan view. The slit 5b of the cover member 5 is formed in an elongated shape extending in the X direction when seen in a plan view. The lens array 6 is fitted in the slit 5 b of the cover member 5 while being sandwiched by the lens holder 7. That is, the lens array 6 is arranged at a predetermined interval from the LED array 3 in the Z direction. The lens array 6 is an example of the “imaging element array” in the present invention.

  As shown in FIGS. 4 and 5, the lens array 6 is composed of a plurality of lenses 6a arranged in a line in the X direction, and the plurality of lenses 6a has an optical axis oriented in the Z direction. It has been adjusted. The plurality of lenses 6a are arranged at a predetermined interval from each other and are bonded to each other by an adhesive member 6b. The lens array 6 collects the light L from the LED array 3 and forms an image on the photoconductor (image carrier) 20. The lens 6a is a refractive index distribution type collecting optical fiber lens that can form an equal magnification image, and is an example of the “imaging element” in the present invention.

  Further, as shown in FIG. 1, a focus adjustment mechanism portion 10 that is screwed to the heat sink 1 with a screw 8 together with the multilayer wiring board 2 is provided on a predetermined surface 1 a of the heat sink 1. The focus adjustment mechanism unit 10 has a function of performing focusing by adjusting the position of the lens array 6 in the Z direction, and is disposed one by one on both ends of the lens array 6 in the X direction. . The focus adjustment mechanism unit 10 according to the present embodiment is configured to be able to convert the movement in the horizontal direction (Y direction) into the vertical direction (Z direction). Below, the structure of the focus adjustment mechanism part 10 of this embodiment is demonstrated in detail.

  As shown in FIGS. 6 to 11, the focus adjustment mechanism unit 10 of the present embodiment includes a movable member 11 that is connected to the lens array 6 (see FIG. 1) and is movably installed in the Z direction. It includes at least an adjustment belt 12 that adjusts the amount of movement of the movable member 11 in the Z direction, and a gear 13 that transmits power from the adjustment belt 12 to the movable member 11. The adjustment belt 12 is an example of the “adjustment member” in the present invention, and the gear 13 is an example of the “transmission member” in the present invention.

  The movable member 11 has a connecting hole 11a formed at the base thereof. And the lens array 6 (refer FIG. 1) is connected with the movable member 11 via the pin (not shown) inserted in the connection hole 11a. The movable member 11 is provided with a male screw 11b extending along the Z direction. Furthermore, the movable member 11 is also provided with a guide pin 11c extending along the Z direction.

  The adjustment belt 12 is installed so as to be movable in the Y direction, and is configured by an elongated plate-like member extending along the Y direction. In addition, a plurality of tooth portions 12 a arranged along the Y direction are formed in a predetermined portion of the plate-like member constituting the adjustment belt 12. The plurality of tooth portions 12 a of the adjustment belt 12 have a shape that meshes with the gear 13.

  The gear 13 is installed such that its rotation axis extends along the Z direction. That is, the gear 13 is rotatable around a rotation axis extending along the Z direction. Further, the gear 13 meshes with the tooth portion 12a of the adjustment belt 12 so as to rotate as the adjustment belt 12 moves in the Y direction.

  The Z direction, which is the direction in which the movable member 11 is movable, is an example of the “first direction” in the present invention, and the Y direction, in which the adjustment belt 12 is movable, is the “second direction” in the present invention. Is an example.

  Here, in the present embodiment, a female screw portion 13 a to which the male screw 11 b of the movable member 11 is screwed is formed at the rotation center of the gear 13. Thereby, if the gear 13 rotates with the movement of the adjustment belt 12 in the Y direction, the movable member 11 is moved in the Z direction. That is, by moving the adjustment belt 12 in the Y direction, power is transmitted from the adjustment belt 12 to the movable member 11 via the gear 13, and the movable member 11 is moved in the Z direction. As a result, the position in the Z direction of the lens array 6 (see FIG. 1) connected to the movable member 11 can be adjusted.

  In the present embodiment, the movable member 11 is attached to the base member 14 fixed to the heat sink 1 (see FIG. 1). Specifically, the movable member 11 is fitted in a recess 14 a formed in the upper part of the base member 14. An insertion hole 14b penetrating in the Z direction is formed at the bottom of the recess 14a of the base member 14, and the male screw 11b of the movable member 11 is inserted into the insertion hole 14b of the base member 14. Further, a counterbore portion 14c in which the gear 13 is disposed is formed at the lower end portion of the insertion hole 14b of the base member 14. The male screw 11 b of the movable member 11 is screwed into the female screw portion 13 a of the gear 13 through the insertion hole 14 b of the base member 14.

  Furthermore, a guide hole 14d penetrating in the Z direction is formed at the bottom of the recess 14a of the base member 14, and a guide pin 11c of the movable member 11 is inserted into the guide hole 14d of the base member 14. . That is, the movement of the movable member 11 in the Z direction is guided by the guide hole 14 d of the base member 14.

  In addition, a guide groove 14 e that guides the movement of the adjustment belt 12 in the Y direction is formed in the lower portion of the base member 14. The guide groove 14e of the base member 14 extends along the Y direction, and a part of the guide groove 14e is connected to the counterbore portion 14c. The tooth portion 12a of the adjustment belt 12 and the gear 13 are engaged with each other through a portion where the counterbore portion 14c of the base member 14 and the guide groove 14e are connected.

  The base member 14 is formed with a female screw portion 14f reaching the guide hole 14d so as to extend along the Y direction. A fixing bolt 15 that presses the guide pin 11c of the movable member 11 in the Y direction is screwed to the female screw portion 14f of the base member 14 at its tip. The fixing bolt 15 is an example of the “pressing member” in the present invention.

  A leaf spring 16 is provided between the movable member 11 and the base member 14 so as to urge the movable member 11 in the Z direction. By providing such a leaf spring 16, the movable member 11 is always urged in the Z direction, so that the movable member 11 can be prevented from rattling in the Z direction.

In the focus adjustment mechanism 10 described above, when the pitch of each of the male screw 11b of the movable member 11 and the female screw portion 13a of the gear 13 is 0.25 mm, the gear 13 rotates once, so that the movable member 11 is rotated. Move 0.25 mm in the Z direction. In this case, if the number of teeth of the gear 13 is 36, 0.25 mm / 36 = 6.94 × 10 ⁻³ mm, so that adjustment can be performed at a pitch of about 7 μm. Thereby, since the position of the lens array 6 (see FIG. 1) connected to the movable member 11 can be adjusted with high accuracy, the focal depths of the plurality of lenses 6a constituting the lens array 6 are compared. Even if it is shallow, it is possible to perform focusing easily.

  Next, as an operation for performing focusing, first, the adjustment belt 12 is moved in the Y direction. At this time, since the tooth portion 12a of the adjustment belt 12 meshes with the gear 13, the gear 13 rotates around the rotation axis extending along the Z direction. Furthermore, when the gear 13 rotates, the screwing amount of the male screw 11b of the movable member 11 with respect to the female screw part 13a of the gear 13 changes. That is, by moving the adjustment belt 12 in the Y direction, the movable member 11 to which the lens array 6 is connected moves in the Z direction. Then, after performing focusing while moving the lens array 6 (movable member 11) in the Z direction, the guide pin 11c of the movable member 11 is pressed in the Y direction by the fixing bolt 15. Thus, the lens array 6 is fixed so as not to move in the Z direction in a focused state.

  In the present embodiment, by using the focus adjustment mechanism unit 10 as described above, the adjustment of the position of the lens array 6 in the Z direction (vertical direction) is performed by moving the adjustment belt 12 in the Y direction (horizontal direction). Can be done. That is, the adjustment width when adjusting the position of the lens array 6 in the Z direction is determined by the movement width of the adjustment belt 12 in the Y direction. Therefore, when the height of the focus adjustment mechanism unit 10 in the Z direction is limited, even if the height of the focus adjustment mechanism unit 10 in the Z direction is reduced, the movement width of the adjustment belt 12 in the Y direction is affected. Therefore, the adjustment width when adjusting the position of the lens array 6 in the Z direction is not narrowed. As a result, the focus adjustment mechanism unit 10 can be thinned without narrowing the adjustment width when adjusting the position of the lens array 6 in the Z direction.

  In the present embodiment, as described above, the gear 13 is installed so that the rotation axis extends along the Z direction, the male screw 11b extending along the Z direction is provided on the movable member 11, and the male screw of the movable member 11 is provided. The internal thread portion 13a into which the gear 11b is screwed is formed at the rotation center of the gear 13, thereby adjusting the screwing amount of the male screw 11b of the movable member 11 with respect to the internal thread portion 13a of the gear 13 to be connected to the movable member 11. The position of the lens array 6 in the Z direction can be adjusted. In this case, if the gear 13 rotates as the adjustment belt 12 moves in the Y direction, the position of the lens array 6 in the Z direction can be easily adjusted by moving the adjustment belt 12 in the Y direction. It becomes possible to do.

  In the present embodiment, as described above, the plurality of tooth portions 12 a arranged along the Y direction are formed on the adjustment belt 12, and the tooth portions 12 a of the adjustment belt 12 are engaged with the gear 13. By moving the adjustment belt 12 in the Y direction, the gear 13 can be easily rotated around the rotation axis extending along the Z direction.

  In the present embodiment, as described above, the guide pin 11c extending along the Z direction is provided in the movable member 11, and the guide hole 14d into which the guide pin 11c of the movable member 11 is inserted is formed in the base member 14. As a result, the guide pin 11c of the movable member 11 is inserted into the guide hole 14d of the base member 14, thereby suppressing rattling of the movable member 11 when the movable member 11 is moved in the Z direction. be able to. Thereby, the movable member 11 can be smoothly moved in the Z direction.

  In the present embodiment, as described above, the female screw portion 14f into which the fixing bolt 15 is screwed is formed on the base member 14, and the female screw portion 14f of the base member 14 reaches the guide hole 14d. By extending 14 f along the Y direction, the fixing bolt 15 is screwed into the female screw portion 14 f of the base member 14 until the tip of the fixing bolt 15 reaches the guide hole 14 d of the base member 14, whereby the guide hole 14 d of the base member 14. It becomes possible to press the guide pin 11c of the movable member 11 inserted into the Y in the Y direction with the tip of the fixing bolt 15. Thus, after performing focusing by adjusting the position in the Z direction of the lens array 6 connected to the movable member 11, the guide pin 11 c of the movable member 11 is pressed in the Y direction with the tip of the fixing bolt 15. Thus, the movable member 11 (lens array 6) can be fixed so as not to move in the Z direction.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above description of the embodiments but by the scope of claims for patent, and further includes all modifications within the meaning and scope equivalent to the scope of claims for patent.

  For example, in the above embodiment, an example in which the present invention is applied to an optical print head using LEDs has been described. However, the present invention is not limited to this, and an optical print head other than an optical print head using LEDs (for example, an organic print head) The present invention can also be applied to an optical print head using an EL).

1 is an overall perspective view of an optical print head according to an embodiment of the present invention. It is sectional drawing along the 100-100 line of FIG. It is a top view of LED array (light emitting element array) of the optical print head by one Embodiment shown in FIG. FIG. 2 is a plan view of a lens array (imaging element array) of the optical print head according to the embodiment shown in FIG. 1. It is a figure for demonstrating the function of the lens array (imaging element array) shown in FIG. It is a perspective view of the focus adjustment mechanism part of the optical print head by one Embodiment shown in FIG. It is a top view at the time of seeing the focus adjustment mechanism part shown in FIG. 6 from the lower side. It is sectional drawing along the 200-200 line | wire of FIG. It is a disassembled perspective view of the focus adjustment mechanism part shown in FIG. It is a perspective view of the movable member contained in the focus adjustment mechanism part shown in FIG. FIG. 7 is a perspective view of a base member included in the focus adjustment mechanism shown in FIG. 6. It is the figure which showed simply an example of the structure of the conventional optical print head.

Explanation of symbols

1 Heat sink (base)
1a Predetermined surface 3 LED array (light emitting element array)
3b LED (light emitting element)
6 Lens array (imaging element array)
6a Lens (imaging element)
DESCRIPTION OF SYMBOLS 10 Focus adjustment mechanism part 11 Movable member 11b Male screw 11c Guide pin 12 Adjustment belt (adjustment member)
12a Tooth part 13 Gear (Transmission member)
13a Female thread part 14 Base member 14d Guide hole 15 Fixing bolt (pressing member)
20 photoconductor (image carrier)

Claims (7)

A light emitting device array mounted on a predetermined surface of the base and including a plurality of light emitting devices for generating light;
The light-emitting element array is disposed at a predetermined interval in a first direction perpendicular to a predetermined surface of the base, and the light from the light-emitting element array is condensed and formed on an image carrier. An imaging element array including a plurality of image elements;
A focus adjustment mechanism provided on a predetermined surface of the base and performing focusing by adjusting a position of the imaging element array in the first direction;
The focus adjustment mechanism adjusts a movable member installed to be movable in the first direction while being connected to the imaging element array, and an amount of movement of the movable member in the first direction. An adjustment member; and at least a transmission member that transmits power from the adjustment member to the movable member. The transmission is performed by moving the adjustment member in a second direction horizontal to a predetermined surface of the base. An optical print head characterized in that power is transmitted from the adjustment member to the movable member via a member so that the movable member moves in the first direction. The transmission member is installed such that the adjustment member rotates as the adjustment member moves in the second direction, and a rotation shaft extends along the first direction.
The movable member is provided with a male screw extending along the first direction, and a female screw portion into which the male screw of the movable member is screwed is formed at the rotation center of the transmission member. The optical print head according to claim 1. The transmission member is a gear installed rotatably about a rotation axis extending along the first direction;
The adjustment member is formed with a plurality of teeth arranged along the second direction,
The optical print head according to claim 2, wherein the gear is meshed with a tooth portion of the adjustment member. The focus adjustment mechanism unit further includes a base member fixed to the base,
The movable member is provided with a guide pin extending along the first direction, and the base member is formed with a guide hole into which the guide pin of the movable member is inserted. The optical print head according to claim 1.   The optical print head according to claim 4, wherein the focus adjustment mechanism unit further includes a pressing member that presses the guide pin of the movable member in the second direction. The light emitting element is a light emitting diode,
The optical print head according to claim 1, wherein the light emitting element array is a light emitting diode array including a plurality of the light emitting diodes.   An image forming apparatus comprising the optical print head according to claim 1.

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