JP4782632B2 - An optical component fixing device and an original reading device including the same. - Google Patents

Description

  The present invention relates to an optical component fixing device that fixes an optical component at a predetermined position, and an original reading device including the optical component fixing device.

  In general, in an optical apparatus, it is required to accurately place an optical component at a predetermined position in an optical path. In addition, from the viewpoint of cost, a mechanism capable of accurately fixing optical components with a small number of components is desired. The simplification of the attachment mechanism also contributes to downsizing of the device.

Typical optical components include lenses, mirrors, light emitting elements, light receiving elements, and the like. Various mechanisms have been proposed for attaching these optical components to a support with high accuracy. For example, there is known a technique in which a groove is formed in a holding body, and a light source or a lens is positioned on two planes among the surfaces on which the groove is formed (for example, see Patent Document 1).
In addition, there is known one that performs positioning by urging a lens in one direction by an elastic member (for example, see Patent Document 2).
Japanese Utility Model Publication No. 63-162310 JP 2003-172896 A

The shape of the optical component is often symmetrical with respect to the axis. For example, there are a cylindrical shape, a polygonal column shape, a shape obtained by flattening them in a direction orthogonal to the axis, a shape having a deformed portion such as a protrusion, and a shape having a step in the axial direction. The axis should often coincide with the optical axis, i.e. the axis of the optical path. Alternatively, the optical axis of the optical system may be determined by the axis of the optical component. A mechanism for attaching optical components having these shapes to predetermined positions of a support tends to be complicated. For example, also in the above-mentioned patent document, there are a plurality of members for supporting the lens, and each member has a complicated shape. A mechanism that determines the position of the optical component in each of the three-dimensional directions with a simple structure, in other words, a mechanism that can accurately determine and fix the position and direction of the optical axis and the position of the optical component in the optical axis direction with a simple structure. It is desired.
The present invention has been made in consideration of the above-described circumstances, and provides a mechanism that can fix the optical component by accurately determining the position in each direction in three dimensions with a small number of components.

The present invention includes a support portion that supports a columnar optical component, an axial direction regulating portion that determines the position of the optical component in the axial direction, and a fixing member that surrounds and fixes the peripheral surface of the optical component to the support portion, The fixing member includes an elastic member that urges the optical component toward the support portion and urges the optical component toward the axial restriction portion.
The present invention also provides an original reading device comprising the optical component fixing device, wherein the optical component is an imaging lens for forming an image of an original on a reading surface.
Here, the optical component is not limited to the imaging lens described above, and may be, for example, a condensing lens that condenses the laser beam in an image forming apparatus that exposes the photosensitive member with the laser beam. If it is an optical component having a columnar outer shape, its function and type are not limited.
The document reading device is a scanning type document reading device including a reduction optical system that scans a document placed on a document table with a scanning unit and forms a scanned document image on an image sensor. Also good.

  In the optical component fixing device according to the present invention, the fixing member includes an elastic member that urges the optical component toward the support portion and urges the optical component toward the axial direction restricting portion. It is possible to fix the optical component by determining the position in each direction in three dimensions.

The optical component has a step portion in the axial direction on the entire circumference or a part of the circumference, the fixing member has a belt-like shape, an attachment portion at both ends and fixed to the support portion, and an optical You may have the pressing part which hold | suppresses the surrounding surface of components, and the engaging part engaged with the level | step-difference part of an optical component. In this way, the fixing member can urge the optical component toward the support portion at the body portion, and can urge the optical component toward the axial direction restriction portion at the engagement portion. The member can bias the optical component in two directions orthogonal to each other.
Further, the optical component may have a shape that is bilaterally symmetric about an axis, and the support portion may support the peripheral surface at a plurality of positions that are symmetric with respect to the axis. In this way, the optical component is supported at a position symmetrical to the axis, so that the axis direction is stable.
Furthermore, the optical component is partially inserted, and the peripheral surface of the inserted optical component has an opening that contacts the edge, and the support portion is a portion of the portion that contacts the peripheral surface of the optical component. It may be an edge. If it does in this way, an optical component can be supported by the simple composition of providing an opening. In addition, the optical component can be stably supported by the edges of the edges of the opening that face each other.

Furthermore, the axial direction restricting portion may be an edge portion of a portion that comes into contact with one end face of the inserted optical component. If it does in this way, in addition to a support part, an axial direction regulation part can also be realized by simple composition of providing an opening.
The optical component may have a circular or regular polygonal cross section perpendicular to the axis.
Further, the fixing member may have one or more projecting portions projecting from the end portion in the width direction of the band as the engaging portion. In this way, the fixing member engages with the optical component at the protruding portion and does not engage at other locations, so that the position for biasing the optical component in the axial direction becomes clear. Accordingly, the optical component can be urged in the axial direction with a stable force.
The optical component has a symmetrical shape about an axis, the support portion supports a peripheral surface of the optical component at a plurality of positions symmetrical with respect to the axis, and the fixing member is configured with respect to the axis. The protrusion part may be arrange | positioned so that it may engage with the level | step-difference part of an optical component in the left-right symmetrical several position. In this way, since the optical component is urged in the axial direction at a position symmetrical to the axis, the urging in the axial direction is stabilized.

  Hereinafter, the present invention will be described in more detail with reference to the drawings. The following description will provide a better understanding of the present invention. In addition, the following description is an illustration in all the points, Comprising: It should be understood that it is not restrictive.

In this embodiment, as a typical example of an optical component, attachment of an imaging lens used in a reduction optical system of a document reading apparatus will be described. First, the overall configuration of the document reading apparatus will be briefly described.
FIG. 9 is an explanatory view schematically showing a mechanical configuration of the document reading apparatus according to the present invention.
FIG. 10 is a block diagram showing the flow of image information in the document reading apparatus according to the present invention. In FIG. 10, the mechanical part of the document reading apparatus shown in FIG. 9 corresponds to the document reading unit 2.

  As shown in FIG. 10, the document reading device 1 includes a document reading unit 2, an image processing unit 5, a storage unit 6, and a communication unit 8. The document reading unit 2 irradiates the document with light, guides the light reflected from the document to the imaging optical system, and reads it with the image sensor 14. The document image signal read by the image sensor 14 is output to the image processing unit 6. The image processing unit 5 performs A / D conversion on the image signal from the image sensor 14 to convert it into image data, and performs image processing such as color conversion processing and filter processing on the converted image data. The storage unit 6 temporarily stores image data to be processed when the image processing unit 5 performs image processing on the image data. In addition, the storage unit 6 holds the processed image data until it has been transferred to an external device via the communication unit 8. The communication unit 8 receives the image data from the storage unit 6 via the image processing unit 5 and transfers it to an external device.

  The image processing unit 5 and the communication unit 8 include, for example, a CPU, a ROM that stores a program to be executed by the CPU, a RAM that provides a working storage area, a nonvolatile memory that stores setting values of each block that performs image processing, It can be configured by a circuit using an LSI or the like in which circuit blocks for image processing and communication are integrated. The storage unit 6 can be composed of a DRAM or other type of memory element. In addition, a storage device such as an HDD can be applied to the storage unit 6.

  The document reading unit 2 shown in FIG. 9 receives a light from a document table 12 having a document placement surface 11, a light source 13 that illuminates a document placed on the document placement surface 11, and a document illuminated by the light source 13. And an imaging optical system 15 that forms an image of light from the original on the imaging device 14. The document table 12 is made of transparent glass and is formed in a rectangular plate shape. The document placement surface 11 is a surface on one side in the thickness direction of the document table 12. A document to be read is placed on the document placement surface 11 by the user of the document reading device. Around the light source 13, a reflecting plate 13 a that collects light from the light source on the document placement surface 11 is provided. The light source 13, the image sensor 14, and the imaging optical system 15 are disposed on the opposite side of the document placement surface 11 with respect to the document table 12. For example, a charge coupled device (abbreviated as CCD) is used as the imaging device 14.

  The imaging optical system 15 includes an imaging lens 16 and a mirror group 17 that guides light from the document to the imaging lens 16. The imaging lens is obtained by fixing a plurality of lenses to a substantially cylindrical frame member, and aluminum, glass-containing resin, or the like is used as the frame member. The mirror group 17 includes a first mirror 17a, a second mirror 17b, and a third mirror 17c. The light emitted from the light source 13 is irregularly reflected on the surface of the document placed on the document placement surface 11. The light reflected downward from the surface of the original is reflected by the first mirror 17 a, and then sequentially reflected by the second mirror 17 b and the third mirror 17 c and guided to the imaging lens 16. The first mirror 17 a is mounted on the first scanning unit 21 together with the light source 13. The second and third mirrors 17 b and 17 c are mounted on the second scanning unit 22.

  The first scanning unit 21 is driven by a drive system including a drive motor, a pulley, and a wire (not shown), and moves at a constant speed V in the direction of the arrow A1 (reading direction). Hereinafter, the reading direction A1 and the direction A2 opposite to the reading direction A1 are referred to as a sub-scanning direction A. The second scanning unit 22 is driven by the drive system and moves in the reading direction A1 at a speed (V / 2) that is a half of the speed V of the first scanning unit 21. As the first scanning unit 21 and the second scanning unit 22 move, the mirror group 17 moves along the document table 12. The position (reading position) of the document imaged on the image sensor 14 moves from the scanning start end P1 to the scanning end P2 as the mirror group 17 moves. During the movement of the first scanning unit 21 and the second scanning unit 22, the speed ratio between them is maintained at 2: 1, so that the optical path length from the document surface to the imaging lens 16 is kept constant. As a result, an image of the document on the document placement surface 11 is formed on the image sensor 14 at each reading position from the scanning start end P1 to the scanning end P2.

FIG. 9A shows a state where the first scanning unit 21 is at a scanning start position outside the scanning start end P1, and FIG. 9B shows a scanning where the first scanning unit 21 is outside the scanning end P2. Indicates the state at the end position.
In FIG. 9, a direction indicated by B (a direction perpendicular to the paper surface) is referred to as a main scanning direction. The main scanning direction B is orthogonal to the sub scanning direction A.

  FIG. 4 is a perspective view showing an example of the shape of each part of the document reading unit 2 according to the present invention. As shown in FIG. 4, the imaging lens 16 is attached to a flat bottom plate 33 as an imaging unit 31 integrated with the imaging device 14. For the bottom plate 33, for example, a steel plate whose surface is galvanized is used. Further, the first scanning unit 21 and the second scanning unit 22 are attached so as to pass in the sub-scanning direction along the bottom plate 33 through the imaging lens 16. Both the first scanning unit 21 and the second scanning unit 22 are supported by guide rails and move on the guide rails.

  The drive motor 35 is a stepping motor that drives the first scanning unit 21 and the second scanning unit 22, and its rotation is controlled by a motor control circuit (not shown). The rotation of the output shaft of the drive motor 35 is transmitted to the drive shaft 39 via a timing belt (not shown), and the drive pulleys 37a and 37b attached to both ends of the drive shaft are rotated. Drive wires 41a and 41b are wound around the drive pulleys 37a and 37b, respectively, and the drive wires 41a and 41b are fixed to both ends of the first scanning unit 21 and the second scanning unit 22, respectively. The rotation of the drive pulleys 37a and 37b is converted into a linear motion by the drive wires 41a and 41b, and reciprocates the first scanning unit 21 and the second scanning unit 22 in the sub-scanning direction. The drive shaft and the drive pulley are made of steel, and a steel wire is used as the drive wire.

  In order to form a sharp original image on the image sensor 14 with such an imaging optical system 15, the first scanning unit 21 and the second scanning unit 22 with respect to the original placement surface 11, the imaging lens 16, and The relative mounting positions of the image sensor 14 are adjusted and assembled one by one. Therefore, it is important to fix the attachment position of the imaging lens 16 accurately and firmly in each of the three-dimensional directions. If the position and direction of the optical axis of the imaging lens 16 are deviated, the image is distorted or the reading position is deviated. Further, when the imaging lens 16 is displaced in the optical axis direction, the image is blurred or the magnification in the main scanning direction is changed. Further, when the ambient temperature changes after adjustment, the relative position between the imaging lens 16 and the image sensor 14 changes due to the difference in linear expansion coefficient between the lens frame member and the support member. For this reason, the imaging lens 16 can be urged and attached to the support member so that one end of the imaging lens 16 is always in contact with the reference surface of the support member in accordance with the characteristics of the image plane drift amount with respect to the temperature of the imaging lens 16. preferable.

(Fixing the imaging lens)
FIG. 1 is a perspective view showing a state in which the imaging lens 16 is attached to the image pickup unit 31 of this embodiment. As shown in FIG. 1, the imaging unit 31 is a lens support plate 53 to which the imaging element 14 and the imaging lens 16 are attached. The image sensor 14 is attached to the image sensor attachment plate 57a, and the image sensor attachment plate 57a is attached to the lens support plate 53 via the image sensor support plate 57b. As the image sensor mounting plate 57a, the image sensor support plate 57b, and the lens support plate 53, for example, a steel plate whose surface is galvanized is used.

  The image sensor 14 is a CCD, and is a linear image sensor in which light receiving elements corresponding to the respective pixels are arranged in the horizontal direction. The mounting position of the image sensor 14 can be adjusted in the main scanning direction in which the light receiving elements are arranged and the optical axis direction of the imaging lens 16. The image signal from the image sensor 14 is connected to a circuit board (not shown) on which the image processing unit 5 of FIG.

  The lens support plate 53 is provided with an opening, and the imaging lens 16 is fixed by the lens fixing band 51 in a state where a part of the peripheral surface is inserted into the opening. Band attachment portions 53 a and 53 b for fixing both ends of the lens fixing band 51 are provided at the edge of the opening of the lens support plate 53. At both ends of the fixed band 51, mounting portions 51a and 51b for mounting the fixed band 51 to band mounting portions 53a and 53b of the lens support plate are provided. From the direction of FIG. 1, the band attaching portion 53 a appears, but the band attaching portion 53 b is hidden behind the imaging lens 16. The attachment of the fixing band will be described in more detail below. The fixed band 51 is attached to the band attaching portion 53a of the lens support plate 53 by the attaching portion 51a. The lens support plate 53 is provided with mounting holes 55a to 55d for mounting the lens support plate 53 to the bottom plate 33 with screws. The attachment holes 55 a to 55 d are elongated holes, and the lens support plate 53 can be adjusted in the optical axis direction of the imaging lens 16 with respect to the bottom plate 33.

  Although not shown in FIG. 1 for easy understanding of the state in which the imaging lens 16 is fixed to the lens support plate 53, stray light enters the imaging element 14 between the imaging element 14 and the imaging lens 16. In order to prevent this, it is covered with a resin dark box 59. At one end of the dark box, a lens holder portion 59a is formed so as to reduce the gap with the imaging lens 16. FIG. 2 is a perspective view showing the imaging unit 31 in a state where the dark box 59 is attached in the embodiment of the present invention. 3 is a perspective view showing a state when the imaging unit 31 is viewed from a side surface different from that in FIG. As shown in FIG. 3, the fixed band 51 is attached to the band attaching portion 53 b of the lens support plate 53 with a screw at the attaching portion 51 b.

  FIG. 5 is a perspective view showing one aspect of the shape of the lens fixing band 51 according to the present invention. As shown in FIG. 5, the lens fixing band 51 is a band-shaped member. For example, stainless steel can be used as the material, but the material is not limited thereto, and any material having flexibility may be used. For example, phosphor bronze can be used.

One end portion 51a of the lens fixing band 51 is provided with a mounting portion 51a that is thinned by cutting out both ends in the width direction into a rectangular shape. As will be described later, the attachment portion 51 a engages with a band attachment portion 53 a that is a notch portion of the lens support plate 53, and fixes one end of the fixed band 51 to the lens support plate 53.
A bent portion is provided at the other end of the lens fixing band 51, and an attachment portion 51b having an elongated screw hole and a circular boss hole is provided at the end of the bent portion. As will be described later, the attachment portion 51b is attached to the band attachment portion 53b of the lens support plate 53 with screws.

  A region near the middle between the attachment portions 51a and 51b at both ends of the lens fixing band 51 is a body portion 51e. As shown in FIG. 1, the lens fixing band 51 presses the imaging lens 16 against the lens support plate 53 with the body 51e. In addition, projecting portions 51 c and 51 d are provided on the edge in the width direction of the lens fixing band 51. The lens fixing band 51 abuts against a step on the peripheral surface of the imaging lens 16 at the protrusions 51c and 51d, and presses the imaging lens 16 in one direction along the optical axis.

  FIG. 7 is an explanatory diagram showing the details of fixing the imaging lens 16 with the lens fixing band 51 in this embodiment. FIG. 8 is an explanatory diagram showing the shape of the opening 61 viewed from the bottom surface side of the lens support plate 53 in this embodiment. The opening 61 has a substantially rectangular shape, and in the vicinity of one of the edges along the optical axis of the imaging lens 16 inserted into the opening, band attaching portions 53a and 53b are provided via the opening. It is provided at an opposing position.

  As shown in FIG. 8, the band attaching portion 53a is a rectangular notch provided at the edge. One end of the lens fixing band 51 is fixed by inserting a portion where the width of the mounting portion 51a of the lens fixing band 51 is narrowed into the notch (see FIGS. 1 and 2). The band attaching portion 53b is provided with a screw hole tapped on the inner periphery and a convex boss on the upper surface side (see the inside of the dotted line ahead of the reference numeral 53b). A boss hole of the mounting portion 51b of the lens fixing band 51 is fitted into the boss, and the mounting portion 51b is positioned. A mounting screw into which the screw hole of the lens fixing band 51b is fitted is screwed into the screw hole (see FIG. 3).

  FIG. 7A is a cross-sectional view showing a C-C ′ cross section of the lens support plate 53 of FIG. 8. A hatched portion indicates a cross section, and a region 62 b where no hatched line is drawn is one edge of the opening 61. The imaging lens 16 is inserted into the opening 61 from above (arrow Y direction). The imaging lens 16 has two steps in the optical axis direction such that the diameters at both ends are larger than those in the middle portion, and the cross section in the direction perpendicular to the optical axis is circular. As a modification, the cross section in the direction perpendicular to the optical axis of the imaging lens 16 may be a regular polygon. Alternatively, even if it is not such an axial target shape, it may be a shape that is symmetrical with respect to the optical axis when viewed from above. Furthermore, there may be partial convex portions or step portions that are not completely axially symmetrical or bilaterally symmetric and do not hinder the positioning of the imaging lens.

  FIG. 7B is a side view showing a state in which the imaging lens 16 inserted into the opening 61 is fixed by the lens fixing band 51. FIG. 7C is a side view showing the imaging lens 16 fixed by the lens fixing band 51 from the side surface on the opposite side to FIG. As shown in FIGS. 7B and 7C, when the lens fixing band 51 is fixed to the lens support plate 53 by the attachment portions 51a and 51b at both ends, tension is generated in the lens fixing band 51, and image formation is performed. The lens 16 is pressed against the lens support plate 53 by the body 51e. The arrows Y in FIGS. 7B and 7C indicate this biasing direction. The peripheral surface of the lens is in contact with both edges 62a and 62b of the opening, and the direction and position of the optical axis are fixed. Here, both edge portions 62a and 62b are within the range surrounded by the dotted lines at the ends of the respective arrows 62a and 62b of the edge of the opening shown in FIG. This is the part that supports the surface. The lens support plate 53 is a support member referred to in the claims, and both edge portions 62a and 62b are support portions referred to in the claims.

  Further, the lens fixing band 51 has a bent portion on the side of the mounting portion 51b. When the lens fixing band 51 is fixed to the lens support plate 53 by the mounting portions 51a and 51b at both ends, the body portion 51e is attached to the mounting portion 51a, It tries to be positioned in the direction directly above 51b. However, in the lens fixing band 51, one end surface of the imaging lens is in contact with the edge 63 of the opening, and the engaging portions 51 c and 51 d of the lens fixing band 51 are in contact with the step portion of the imaging lens 16. When fixed in the above state, it is slightly inclined with respect to the vertical direction. In other words, the positions of the band fixing portions 53a and 53b are set so that the lens fixing band 51 is slightly inclined with the imaging lens 16 fixed. As a result, the mounting portion of the lens fixing band 51 is twisted, and the imaging lens 16 is urged in the direction of the arrow X (the optical axis direction) by the flexibility of the lens fixing band 51, and the end surface contacts the edge 63. Positioned in contact. Here, the edge 63 is within the range surrounded by the dotted line of the arrow of the reference numeral 63 among the edges of the opening 61 shown in FIG. 8, and one end face in the optical axis direction of the imaging lens 16 is in contact with the edge 63. It is the part that touches. The edge portion 63 is an axial direction restricting portion referred to in the claims.

  Although the example of FIG. 5 has two engaging portions, the number of engaging portions may be an even number of two or more, such as four or six. The position at which the engaging portion is engaged with the step portion of the imaging lens 16 is preferably symmetrical with respect to the optical axis when viewed from above. This is because a rotating moment that rotates the imaging lens 16 in the horizontal plane is not generated in a state where the end surface of the imaging lens 16 is in contact with the edge portion 63 and is biased. In addition, it is preferable to engage with a position closer to the lens support plate 53 (lower position) than near the top of the imaging lens 16. This is because the rotational moment in the direction in which the imaging lens is lifted from the support portion is reduced in a state where the end surface of the imaging lens 16 is in contact with the edge 63 and is urged.

  FIG. 6 is a perspective view showing a different aspect of the lens fixing band 51 according to the present invention. The lens fixing band 51 shown in FIG. 6 has only one engaging portion 51c. As shown in FIG. 5, it is more stable to bias the imaging lens 16 toward the edge 63 with a plurality of engaging portions. However, it is also possible to bias the imaging lens 16 in the X direction with one engaging portion. In this way, the work of fixing the lens fixing band 51 in contact with the step portion of the imaging lens 16 is facilitated. That is, the assembly operation of the imaging unit 31 is facilitated.

  Note that, as in this embodiment, since the member for fixing the imaging lens has a belt-like shape, there is an advantage that the fixing member does not protrude from the peripheral surface of the imaging lens 16. In the document reading apparatus of this embodiment, the first scanning unit 21 passes immediately above the imaging lens 16. In general, the original reading apparatus 1 is required to be thin. However, by fixing the imaging lens 16 with a belt-like member as shown in FIG. 5 or FIG.

(Other variations)
In the above embodiment, the imaging lens used in the reduction optical system of the document reading apparatus has been described as an example of the optical component. However, the optical component according to the present invention is not limited thereto. For example, there is an image forming apparatus having a laser writing optical system for condensing a laser beam and exposing a photosensitive member. This laser writing optical system can also be applied to a condenser lens for condensing a laser beam.

  The imaging lens 16 shown in FIG. 7 has a step portion on the entire circumference. However, the stepped portion may be only in a part of the circumference. FIG. 11 is a side view showing a shape having a step on a part of the circumference of the imaging lens 16 as a different embodiment of the imaging lens according to the present invention. FIG. 11A shows a shape having a step only on the upper portion of the imaging lens 16, and FIG. 11 (c) shows an example in which a pin is erected on a part of the peripheral surface of the lens and the side wall of the pin corresponds to a stepped portion. In this case, the engaging portion of the lens fixing band 51 is a hole formed so as to engage with the pin.

  Finally, it is apparent that there can be various modifications of the present invention in addition to the above-described embodiment. Such variations should not be construed as not belonging to the features and scope of the invention. The scope of the present invention is intended to include all modifications within the meaning and range equivalent to the scope of the claims.

It is a perspective view which shows a mode that the imaging lens 16 is attached to the imaging unit 31 of this embodiment. In the embodiment of the present invention, it is a perspective view showing the imaging unit 31 with a dark box 59 attached. It is a perspective view which shows a mode when the imaging unit 31 is seen from the side different from FIG. 3 is a perspective view showing an example of the shape of each part of the document reading section 2 according to the present invention. FIG. It is a perspective view showing one mode of shape of lens fixed band 51 concerning this invention. It is a perspective view which shows the different aspect of the lens fixing band 51 which concerns on this invention. In this embodiment, it is explanatory drawing which shows the detail of a mode that the imaging lens 16 is fixed with the lens fixing band 51. FIG. In this embodiment, it is explanatory drawing which shows the shape of the opening part 61 seen from the bottom face side of the lens support plate 53. FIG. It is explanatory drawing which shows typically the mechanical structure of the document reader concerning this invention. FIG. 3 is a block diagram showing a flow of image information in the document reading apparatus according to the present invention. It is a side view which shows the shape which has a level | step difference in a part of periphery of an imaging lens as different embodiment of the imaging lens which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Original reading apparatus 2 Original reading part 5 Image processing part 6 Memory | storage part 8 Communication part 11 Original mounting surface 12 Original stand 13 Light source 13a Reflecting plate 14 Imaging element, CCD
15 imaging optical system 16 imaging lens 17 mirror group 17a first mirror 17b second mirror 17c third mirror 21 first scanning unit 22 second scanning unit 31 imaging unit 33 bottom plate 35 drive motors 37a and 37b drive pulley 39 drive shaft 41a, 41b Drive wires 43a, 43b
51 Lens fixing bands 51a and 51b Attachment portions 51c and 51d Engagement portions 51e Body 53 Lens support plates 53a and 53b Band attachment portions 55a to 55d Attachment holes 57a Image sensor attachment plates 57b Image sensor support plates 59 Dark box 59a Lens holder 61 Openings 62a, 62b Support 63 Axial restricting portion

Claims (7)

A support for supporting the columnar optical component;
An axial restriction that defines the position of the optical component in the axial direction;
A fixing member that surrounds the peripheral surface of the optical component and is fixed to the support portion;
The optical component has an axial step on the entire circumference or a part of the circumference,
The fixing member is made of an elastic member having a belt-like shape, and is engaged with a mounting portion at both ends and fixed to the support portion, a pressing portion for pressing the peripheral surface of the optical component, and a step portion of the optical component. And at least one projecting portion projecting from the end portion in the width direction of the belt , and biasing the optical component toward the support portion and biasing toward the axial direction restricting portion. An optical component fixing device. The optical component has a symmetrical shape about an axis,
The optical component fixing device according to claim 1, wherein the support portion supports the peripheral surface at a plurality of positions symmetrical to the axis. The optical component is partially inserted, and the peripheral surface of the inserted optical component has an opening that comes into contact with the edge,
The optical component fixing device according to claim 1, wherein the support portion is an edge portion of a portion that abuts on a peripheral surface of the optical component. 4. The optical component fixing device according to claim 3, wherein the axial direction restricting portion is an edge portion of a portion that abuts against one end face of the inserted optical component.   The optical component fixing device according to claim 1, wherein the optical component has a circular or regular polygonal cross section orthogonal to the axis. The optical component has a symmetrical shape about an axis,
The support part supports the peripheral surface of the optical component at a plurality of positions symmetrical to the axis,
The fixing member, an optical component fixing device of the optical component formed by protrusions arranged to engage with the step portion according to claim 1, wherein at symmetrical plurality of positions with respect to the axis. Comprising the optical component fixing device according to any one of claims 1 to 6 ,
An original reading apparatus, wherein the optical component is an imaging lens for forming an image of an original on a reading surface.

Images