JPH033562A - Position adjustment mechanism for picture reader - Google Patents

Abstract

PURPOSE:To attain fine adjustment easily and accurately without interference between a photoelectric conversion element (CCD) and a lens mutually by mounting the CCD so as to turn around 1st and 2nd support shafts and so as to slide and turn around a 3rd support shaft orthogonal to both the support shafts. CONSTITUTION:CCDs 1-3 are adjusted turnably and movably around a 1st support shaft 33 having its shaft axis prolonged in the optical axis direction of image forming lenses 4-6, around a 2nd support shaft 35 having its shaft axis prolonged in the optical axis direction of image forming lenses 4-6, and around a 3rd support shaft 64 and in its axial direction prolonged in the direction orthogonal to both the support shafts 33, 35 while the CCDs are independently without mutual disturbance. When the CCD is positioned, the adjustment of the picture element array in the main scanning direction, the adjustment in the subscanning direction, the adjustment in the lens optical axis direction and the adjustment around the axis in the direction orthogonal to the lens optical axis are implemented minutely easily with accuracy without mutual interference.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention provides photoelectric conversion of an original image by relatively moving an original image projected by an imaging lens and a photoelectric conversion element that reads the original image in the sub-scanning direction. The present invention relates to a position adjustment mechanism for an image reading device that reads images.

[Prior Art] In recent years, optical reading devices for document images have been widely used in office equipment such as copying machines and facsimile machines. The size of documents to be read in general is limited to a maximum of A3 size,
In certain fields such as industrial drawings, the target manuscript size is @841nu (JISAO size) to 3.
Some are larger, such as 671 (941no) (ANSI E size). For such a large document, one photoelectric conversion device (hereinafter referred to as COD) is required.

), it is impossible to reduce the image and read it.
Conventional reading devices for general office use cannot perform reading with sufficient image density.

Therefore, an apparatus has been proposed in which a large document image is dividedly projected onto a plurality of CCDs using a plurality of imaging lenses, and the image is read in correspondence with each projected image.

[Problems to be Solved by the Invention] However, in such a split-type reading device, for example, not only the main scanning direction of each CCD is completely the same in the width direction of the original image, but also each CCD is It is impossible to photoelectrically read the original image unless the COD is positioned so that it is perpendicular to the optical axis and the original image and the photoelectric conversion element are moved relative to each other.

In particular, for high-density COD linear sensors used when high-density reading is required, highly accurate position adjustment must be performed in relation to the projection magnification or reading overlap amount for each CCD, as well as temperature changes. .

Conventionally, JP-A-51-51217, JP-A-59-
Although various CCD support structures have been proposed in Japanese Patent Application Laid-open No. 201572, Japanese Patent Application Laid-open No. 59-201575, Japanese Patent Application Laid-open No. 62-277852, and even Japanese Patent Application Laid-Open No. 62-89916, COD pixels None of the above discloses a technique for adjusting the surface angle of the array with respect to the optical axis of the imaging lens, a technique for adjusting the parallelism with respect to the original image exposure surface, or a technique for adjusting the seam of the read image. It is not fully compatible with the current situation. Furthermore, the locking technology for adjusting the position of the COD is also insufficient, resulting in the problem that the COD cannot be properly adjusted.

In positioning the COD, the present invention prevents the adjustment of the pixel row in the main scanning direction, the sub-scanning direction, the lens optical axis direction, and the adjustment around the axis in the direction orthogonal to the lens optical axis to interfere with each other. It is an object of the present invention to provide a position adjustment mechanism for an image reading device that allows fine adjustment to be made accurately and easily without any problems.

[Means for Solving the Problems] In order to achieve the above object, the invention described in claim 1 projects a document image onto a photoelectric conversion element using an imaging lens, and combines the document image and the photoelectric conversion element. In the position adjustment mechanism of the image reading device, the position adjustment mechanism of the image reading device is configured to photoelectrically read the original image by relatively moving the image forming lens in the sub-scanning direction. The shaft and a second support shaft having an axis extending in a direction perpendicular to the optical axis direction of the imaging lens are sandwiched between each other so as to be rotatable around the axis of the other side. With,
The photoelectric conversion element is held on one of the first support shaft and the second support shaft, and the photoelectric conversion element is attached to the first support shaft and the second support shaft. A rotating device yA adjusting means for rotating around a support shaft is attached, and the first support shaft and the second support shaft are connected to a third support shaft extending in a direction perpendicular to both support shafts. The shaft is configured to be slidably and rotatably mounted on the shaft.

Further, the invention described in claim 2 is the position adjustment mechanism of the image reading device described in claim 1, which includes:
The photoelectric conversion element is provided with a rotation fine adjustment means for rotating the photoelectric conversion element around a third support shaft.

Furthermore, the invention described in claim 3 is based on claim 1.
In the position adjustment mechanism for an image reading device described in , the photoelectric conversion element is provided with a sliding fine adjustment means for sliding the photoelectric conversion element along a third support shaft. .

[Function] In the means having such a configuration, the rotation is performed around a first supporting shaft having an axis extending in the optical axis direction of the imaging lens.
and a second supporting shaft having an axis extending in a direction perpendicular to the optical axis direction of the imaging lens, and a third supporting shaft extending in a direction perpendicular to both the above-mentioned supporting shafts. The rotation and movement of the CCDs are adjusted separately and independently in a non-interfering manner in the axial direction and periaxial direction of the support shaft.

[Example] Hereinafter, an example of the present invention will be described in detail based on the drawings.

As shown in FIG. 1, the yK H12 is illuminated by a long illumination lamp 11, and thereby
The upper image is a one-dimensional photoelectric conversion element (hereinafter referred to as C
The image is projected onto a 1.2°3 pixel column (abbreviated as CD).

Each light beam 7°8.9 in the imaging lenses 4, 5.6 is transmitted to a predetermined area 2□! on the exposure line 13. -122
3 are overlapped, and the CCDI, 2, 3
When the read signal is output to a writing device (not shown), control is performed to prevent omissions, duplications, shifts, etc. from occurring at predetermined positions in each overlap area.

The document 12 is conveyed by a conveying means (not shown) along an exposure line 13 on a transparent flat glass plate from its leading edge to its trailing edge in the direction of the arrow shown in the figure at a speed corresponding to a predetermined reading speed. This allows all images of the document to be read.

Further, as shown in FIG. 2, the area Q2 on the exposure line 13 of Mai12 is 0.0.
It is reduced in size by 1102 times and is imaged on a pixel column of CCD2. C0D2 consists of a linear sensor having 5000 pixels (7 μm×7 μm), and the length of the pixel row is set to 35a++. Therefore, the length of the region Q2 is 317.5n
m. Here, the width of the original 12 on the exposure line 13, that is, the maximum reading IllΩ, is 914.4 am.
Then, the amount of overlap on the exposure line 13 is □
QZ3 is 6.35 peng, and on the pixel column 2a of C0D2, it is Q, 7 am (100 pixels).

In this way, the image of the original 12 is transferred to multiple CCDIs.

In order to read the image separately according to 2.3, each C0DI, the reading magnification and position of the read image in 2.3,
The range etc. needs to be positioned with a predetermined accuracy. Therefore, in this embodiment, as shown in FIG.
The position of 2 is movable for parallel fine adjustment in each direction: the X-axis direction which is the main scanning direction, the Y-axis direction which is the sub-scanning direction, and the Z-axis direction which is the optical axis direction of the imaging lens 5. , can be rotated and finely adjusted around each of the X-axis direction, Y-axis direction, and Z-axis direction.

As shown in FIGS. 3, 4, and 5, the reading unit 15 has an imaging lens 5 with respect to the base 200.
A base plate 100 having a U-shaped cross section is mounted for parallel fine adjustment movement in the optical axis direction (Z-axis direction), and the optical center of the imaging lens 5 is perpendicular to the optical axis with respect to this base plate 100. , and a rotary base plate 8o mounted for fine rotational adjustment around a conical shaft 94 having an axis in the sub-scanning direction, and a rotary base plate 8o mounted on the upper wall 80d of the rotary base plate 80 in a direction perpendicular to the optical axis. a shading correction plate 97 movably screwed to the
The optical center of the imaging lens 5 is screwed to approximately the center of the front side wall 80c of the rotary base plate 80 so as to allow fine rotational adjustment around a conical shaft 94 having an axis perpendicular to the optical axis and in the sub-scanning direction. A support shaft 64 is provided between the lens unit 300 and the right boss 81 and left boss 82 screwed to the lower parts of the right side wall 80a and left side wall 80b of the rotating base plate 80. , and a CCD base plate unit 30 mounted on the support shaft 64 so as to be finely adjustable in rotation and finely adjustable in the axial direction.

A COD unit 20 is held in the CCD base plate unit 30, and a sealing member 310 having light-shielding properties, dust-proofing properties, and air permeability is installed between the COD unit 2o and the lens unit 300. .

Further, as shown in FIGS. 14, 15, and 16, the base 200 is connected to the exposure line 13 of the original image.
The left support frame 230 is provided as an immovable member.
It is rotatably supported on the right support frame 231 via a left main shaft 215 and a right main shaft 217. The rotation plane is set to a plane that includes the optical center of the imaging lens 5 and is orthogonal to the optical axis of the imaging lens 5, and the left main axis 215 and the right main axis 217 are in the main scanning direction of the CCD, that is, the exposure direction. It has an axis in a direction parallel to the line 13. Further, two stop shafts 214 are provided on both sides of the left main shaft 215 in the direction perpendicular to the axis, and when these stop shafts 214 are tightened or loosened by set screws 222 and 223, the base 200 is rotated. The movement can be fine-tuned.

The CCD 2 of the COD unit 20 is fitted into a substantially rectangular positioning hole 21g provided in the metal plate 21, as shown in FIGS. 7 and 8. At the edge of the positioning hole 21g, three support pieces are formed to protrude inward, and a main scanning direction base 1911+2 is formed at the tip of each support piece.
1a and the sub-scanning direction reference edges 21b and 21c,
The end face in the main scanning direction and the end face in the sub-scanning direction of the ceramic case of the CCD 2 are held in contact with each other.

Furthermore, the reference edge 21a in the main scanning direction and the reference edges 21b, 21c in the sub-scanning direction are accurately positioned with respect to the two mounting holes 21e provided in the metal plate 21, so that the pixel row 2a of the CCD 2 Positioning is performed with a predetermined accuracy. At this time, the cover glass 2b of C0D2 and the upper surface of the metal plate 21 are positioned on the same plane. Furthermore, a two-component epoxy resin is injected and hardened into the gap between the ceramic case of C0D2 and the positioning hole 21g, so that the CCD 2 remains immovable.

In addition, the CCD control board PCB-122, which includes an amplification circuit for amplifying the image reading signal by the C0D2, is connected to the CCD2.
It is held by soldering to two connecting pins 2C.

There are two connectors 23 on the COD control board PCB-122.
are soldered, and flat cables 24 made up of a plurality of lead wires are each removably attached. C.O.
Mounting hole 22a provided on D control board PCB-122
A thermistor 25 for detecting the temperature of the CCD 2 is attached to the holder, and is held in contact with the ceramic case of the CCD 2 by adhesion with an epoxy resin.

Furthermore, the CCD control board PCB-122 has a connector 23.
is soldered, and one end of a flat cable 24 is inserted into this connector 23. The other end of the flat cable 24 is connected to a CCD control board PC.
It is inserted and connected to a connector 401 soldered to the B-2400 (see FIGS. 3 and 5). The CCD control board PCB-2400 constitutes a drive control circuit for the CCD 2, and is larger than the CCD control board PCB-122 and is equipped with more control electronic components, so it also generates less heat. big. Therefore, it is desirable that this COD control board PCB-2400 is installed as far away from the CCD 2 as possible, and in this embodiment, the COD control board PCB-2400 is installed with respect to the right support leg 100d and the left support leg 100e extending downward from the base plate 100. screw 404
By being locked by the CCD control board PCB-1
The heat generated by the CCD 22 is prevented from affecting the CCD 2.

The CCD control boards PCB- which are spaced apart from each other in this way
122 and the COD control board PCB-2400 using the flat cable 24, it is conceivable that electrical noise will be picked up through the flat cable 24, making it impossible to output accurate signals corresponding to the original image. However, in this example, as mentioned above, C0D
The CCD control board PCB-122, which is directly connected to the PCB-2, has a read signal amplification function, thereby minimizing the effects of electrical noise. As a result, the flat cable 24 can be lengthened to a certain extent, which alleviates the positional restrictions on the CCD control board PCB-2400, and also allows the CCD 2 to be adjusted in position over a relatively large range without applying undue force to the CCD 2. This makes it possible to eliminate poor connection between the flat cable 24 and the connectors 23, 401 without imposing any load.

9 and 10 show other mounting structures for the CCD 2. In other words, at the edge of the positioning hole 21g,
Main scanning direction reference 121a and sub scanning direction reference J321
In addition to the reference edges 21f in the optical axis direction, three reference edges 21f in the optical axis direction are provided in addition to reference edges 21f in the optical axis direction.
The cover glass 2b of 0D2 is brought into contact and positioned. A two-component epoxy resin is injected and hardened into the gap 21d between the ceramic case of the CCD 2 and the positioning hole 21g, so that the CCD 2 remains immovable. In this way, positioning of the C0D2 with respect to the metal plate 21 in the optical axis direction can be facilitated.

Furthermore, FIG. 11 shows another mounting structure for the CCD control board PCB-122.
A socket 26 is connected to the CB-122 via a connecting pin 26a, and a connecting pin 2C of the CCD 2 is inserted into the socket 26. In this way, the CCD 2 can be replaced by inserting the connecting pin 2c of the CCD 2 into the socket 26, or the CC
The D control board PCB-122 can be replaced easily and inexpensively.

Next, the lens unit 300 will be explained with reference to FIGS. 13, 5, and 3. The lens holder 301 is formed from an aluminum casting with a cross-sectional shape, and the rear part 301b of the lens holder 301 has three protrusions 301.
e is formed, and an attachment hole 303 to the rotating base plate 80 is also formed. The protruding end flat portion of the convex portion 301a and the holder lower surface portion 301d are cut so as to have a perpendicular relationship, and furthermore, with these both surfaces 301e and 301d as a reference, a fitting portion for housing the imaging lens 5 is formed. A hole 304 is formed through the optical axis direction. That is, the axis of the fitting hole 304 is precisely positioned to be perpendicular to the holder lower surface 301d of the lens holder 301 and parallel to the flat surface of the protruding end of the convex portion 301e. The imaging lens 5 is fitted into the fitting hole 304 so as to be slid back and forth in the direction of its front axis.

Further, a fitting hole 302 is formed in the rear part 301b of the lens holder 301, into which the outer circumference of the cylindrical female thread 95 is fitted. The cylindrical female screw 95 is used to lock the conical shaft 94 to the front wall 80c of the rotating base plate 80. At this time, the formation position of the fitting hole 302 is precisely set on the optical center of the imaging lens 5 in a direction perpendicular to the optical axis of the lens and perpendicular to the flat surface of the protruding end of the convex portion 301e. There is. On the other hand, a movable base plate 5o holding the CCD base plate unit 3o is rotatably and slidably supported on the support shaft 64, and the lens unit 30.0 can be rotated around the fitting hole 3o2. After adjusting and setting the holder lower surface portion 301d to be parallel to the support shaft 64, it is secured to the rotating base plate 8o with three screws 309. This ensures the required perpendicular precision between the optical axis of the imaging lens 5 and the support shaft 64.

Further, the tip of the plate spring 325 screwed to the front part 301a of the lens holder 301 is connected to the imaging lens 5.
The lens 5 is pressed against the upper part of the lens 5, so that the imaging lens 5 is pressed downward in the optical axis direction.

A fitting hole 305 is formed in the front part 301a of the lens holder 301 in a direction perpendicular to the lens optical axis.
A focus adjustment shaft 306 is rotatably fitted into the fitting hole 305 for finely adjusting and moving the imaging lens 5 in the optical axis direction for focusing and locking. Further, a screw hole 301f is formed in the front part 301a of the lens holder 301 so as to be perpendicular to the axis of the fitting hole 305, and a pressure rod 307 loosely fitted into the screw hole 301f is screwed into the screw hole 301f. By being pressed by 308, the focus adjustment shaft 306 is pressed in a direction perpendicular to the axis, thereby locking the focus yA adjustment axis 306 at a predetermined position as described later. The pressure rod 307 is made of a flexible hard resin.

On the other hand, a groove 322 of a predetermined depth is formed in an annular shape on the outer periphery of the lens barrel 321 of the imaging lens 5.
A cylindrical eccentric cam 306a is formed at the rear end of the focus adjustment shaft 306, and this eccentric cam 306a is engaged in the groove 322. The eccentric cam 306a is formed to have a diameter of 8awn, and is offset by 1.5 mm with respect to the main axis 306c of the focus adjustment shaft 306.

The length in the axial direction is set longer than the depth of the groove 322. The main shaft 306c of the focus adjustment shaft 306 is formed into a cylindrical shape with a diameter of 12 mm, and a conical portion 306d with an apex angle of 90° is formed on the opposite side of the eccentric cam 306c, and this conical portion 306d is connected to the small diameter shaft 306e. It is integrally connected to the auxiliary shaft 306f via. Auxiliary shaft 306f
is formed to have the same diameter as the main shaft 306c, and the auxiliary shaft 306
A slotted portion 306g into which a driver can be fitted is formed on the end face of f. A conical portion 307a formed at the tip of the pressure rod 307 described above is pressed into contact with the conical inclined side surface of the conical portion 306d. Component forces Pl and P2 of the pressing force of the pressure rod 307 at these pressure contact points are directed in the axial direction and the direction perpendicular to the axis of the black spot adjustment shaft 306, respectively, and the axial component force P1 causes the tip of the eccentric cam 306a to The surface 306b is pressed against the groove bottom surface 322a of the groove 322, and thereby the lens barrel 321
is pressed against the wall surface of the fitting hole 304 and maintained without any play. In addition, the upper shaft 306c of the focus adjustment shaft 306 and the auxiliary shaft 3
06 is pressed against the wall surface of the fitting hole 305 and maintained without any play, and rotation of the focus adjustment shaft 306 is braked by frictional force. At this time, the pressing force against the groove bottom surface 322a by the end surface 30Gb of the eccentric cam 306a, that is, the frictional force between the lens barrel 321 and the fitting hole 304, is based on the pressing force from the set screw 308 against the pressure rod 307. However, at least when the imaging lens 5 focuses the projected image on the CCD 2, the frictional force between the lens barrel 321 and the fitting hole 304 is applied to the lens barrel 32.
The pressing force from the set screw 308 against the pressure rod 307 is adjusted to such an extent that it does not become larger than the pressing force from the leaf spring 325 against the pressure rod 307 .

To adjust the focus of the imaging lens 5, first, a driver is engaged with the slotted portion 306g to rotate the focus g alignment axis 306. As a result, the eccentric cam 306a is eccentrically rotated, and the imaging lens 5 is moved in the optical axis direction, so that the CCD 2
The focus of the projected image is adjusted. At this time, the imaging lens 5 is prevented from rotating around the optical axis by the pressing force of the leaf spring 325, and the groove 3
The groove side surface 322b of No. 22 is maintained in pressure contact with the cam surface of the eccentric cam 306a.

As a result, the imaging lens 5 is always movable for fine focusing adjustment in the most desirable direction for reading the original image, that is, in the direction to eliminate single-focal blur in the main scanning direction, and at this time, in the optical axis direction. It is intended to be maintained in a state of no play.

After the focus adjustment is completed, the set screw 308 is further screwed in to increase the above-mentioned axial component force P and axis-perpendicular component force P2, thereby causing the imaging lens 5 to move against the lens holder 3047. The focus adjustment shaft 306 is reliably locked without any positional deviation, and the rotation of the focus adjustment shaft 306 is restrained.

Next, regarding the adjustment mechanism for CCD2, see Figures 3 and 4.
The explanation will be given based on FIG. 5, FIG. 12, FIG. 18, and FIG. 19.

First, as described above, the rotary machine IA adjustment mechanism of the tilt in the X-axis direction, which is the main scanning direction of the CCD 2, that is, the rotary machine IA adjustment mechanism around the Y-axis α, and the rotation fine adjustment mechanism around 24 times γ, which is the optical axis direction of the imaging lens 5, are as follows. A CCD unit 2o, which has a metal plate 21 that holds the CCD 2 at a fixed reference position, attaches countersunk screw pins 32 to two circular pedestals 31d formed on the upper surface of the channel 31 corresponding to the two reference mounting holes 21e. It is fixed by screwing it on. This allows C0
D2 can be easily replaced within a positional deviation range of 200 to 300 μm.

The CCD control board PCB-122 is positioned so as to protrude downward from a rectangular mounting hole 31a formed in the channel 31.

A substantially cylindrical horizontal shaft 33 is attached to the lower surface side of the right end portion of the channel 31 in the X-axis direction in FIG. 12 so as to extend in the Y-axis direction. This horizontal axis 33 is
Both end portions are cut out into a substantially semi-cylindrical shape, and the plane portions of the semi-cylindrical cutout portions 33C are brought into contact with the lower surface side of the channel 31 and fixed by countersunk screws 34.

Further, two conical portions 33a are formed in the central portion of the horizontal shaft 33 so as to face each other, and both of these conical portions 33a form a rectangular notch portion 31c formed in the channel 31. is housed within. On the other hand, on the upper surface side of the right end portion in FIG. 12 in the X-axis direction of the movable base plate 50, a vertical shaft 35 is erected in the Z-axis direction (optical axis direction).
A cylindrical portion 35a formed at the upper end portion of this vertical shaft 35
The lower outer circumferential edge of is in contact with the conical inclined side surfaces of two conical portions 33a formed on the horizontal shaft 33. As a result, the channel 31 including the CCD unit 20
The entire body is rotatable about a horizontal axis 33 and a vertical axis 35.

A square bar 38 is fastened to the left end portion of the channel 31 in the X-axis direction in FIG. They are screwed together. This adjustment screw 39 is
It protrudes downward through a large diameter hole (not shown) formed in the channel 31, and its spherical tip portion 3
9a is the upper surface 50i of the movable base plate 50 having a U-shaped cross section.
is in contact with.

On the other hand, single-stage pins 36a and 36b are provided on the front wall 31e and rear wall 31f of the channel 31 in the Y-axis direction.
are respectively screwed in the vicinity of the square rod 38, and the upper ends of tension springs 37a and 37b are hung on these stepped pins 36a and 36b, respectively. The lower ends of the tension springs 37a and 37b are hung on stepped pins 54a and 54b screwed onto the front wall 50g and rear wall 50h of the movable base plate 50, respectively. These tension springs 37a and 37b
The square bar 38 extends obliquely to form an angle of about 45'' with respect to the Z axis (optical axis), and its tensile force causes the square bar 38 to
A component force is generated inside the vicinity that presses the channel 31 downward and to the right in FIG. Then, due to the rightward suppressing force by the tension springs 37a and 37b, the lower outer peripheral edge 35a of the cylindrical portion of the vertical shaft 35 is moved into the conical shape of the two conical portions 33a formed on the horizontal shaft 33. At the same time as being pressed against the inclined side surface,
The lower surfaces of the cylindrical portions 33b at both ends of the horizontal shaft 33 are brought into pressure contact with the upper surface 50a of the movable base plate 50 by the downward suppressing force exerted by the tension springs 37a and 37b. As a result, the entire channel 31 including the CODCD unit 2 is connected to the vertical shaft 35 via the horizontal shaft 33 and the movable base plate 5.
0, the three-point support state is maintained. Further, due to the downward pressing force of the tension springs 37a and 37b, the spherical tip portion 39a of the adjustment screw 39 screwed onto the square rod 38 is pushed against the upper surface 50 of the movable base plate 50.
It is designed to be pressed against i. Therefore, by rotating the adjustment screw 39, the channel 31 is adjusted to the horizontal axis 33.
It is rotated around the Y axis, that is, in the α direction, and positioned.

At this time, the stepped pins 36a and 36b are connected to the horizontal axis 3.
3 and the adjustment screw 39, and the adjustment screw 39
Since the lower surfaces of the cylindrical portions 33b on both end sides of the horizontal shaft 33 are urged to be more strongly pressed against the upper surface 50a of the movable base plate 50, the two are separated from each other. It is designed to be closely attached without any problems. Further, the biasing force of the stepped pins 36a and 36b is set to such an extent that the channel 31 is not prevented from rotating around the vertical axis 35.

Furthermore, a spring hook portion 38g is formed to protrude from the left end portion of the channel 31 in the X-axis direction in FIG. It is being On the other hand, a square bar S1 is screwed and fixed to the side surface of the movable base plate 50, and the other end of the tension spring 40 is hung on a stepped pin 52 provided upright on the square bar 51. ing.

Due to the biasing force of this tension spring 4o, the channel 31
The whole can be rotated toward the front about a vertical axis 35. Also, the screw hole 5 provided in the square bar 51
An adjustment screw 53 is screwed into 1a, and a spherical tip portion 53a of this adjustment screw 53 is in contact with the front side wall surface 31a of the channel 31 in the Y-axis direction. Therefore, by rotating the adjustment screw 53, the channel 31
is rotated about the vertical axis 35 around the Z axis, that is, in the γ direction, and positioned.

The fine adjustment mechanism having such a configuration allows fine adjustment of the inclination in the X-axis direction, which is the main scanning direction, that is, the rotational fine adjustment in the α direction around the Y-axis, and the rotational fine adjustment in the α direction, which is the optical axis direction of the imaging lens 5.
Fine rotational adjustment of the direction is performed accurately. That is, by first rotating the adjustment screw 39, the tension spring 37a
, 37b, the channel 31 is rotated about the horizontal axis 33, thereby positioning the CCD 2 in the α inclination direction. At this time, since the rotation center position and the adjustment action position are separated from each other, fine adjustments can be made without using a complicated mechanism such as a differential screw. Note that when adjusting the inclination using the adjustment screw 39, the spherical tip portion 53a of the adjustment screw 53 is slid while being in contact with the front side wall surface 31e of the channel 31 in the Y-axis direction. Since the perpendicularity of the side wall surface 31e to the horizontal axis 33 is maintained at the required precision, the channel 31 is hardly rotated around the vertical axis 35 due to the sliding movement, and there is no problem in adjustment. . Further, since the horizontal axis 33 is provided at a position sufficiently apart from the CCD 2, the CCD
2, the CCD 2 is hardly displaced in the X-axis direction, which is the main scanning direction.

- By rotating the force adjustment screw 53, the channel 31 is rotated about the vertical axis 35 in the γ direction around the Z axis against the tension spring 40, and positioning is performed, and the exposure shown in FIG. The parallelism of the pixel row of the CCD 2 with respect to the line 13 is adjusted. Even in this case, since the rotation center position and the adjustment position are spaced apart, fine adjustment can be made without using a complicated mechanism such as a differential screw. Note that when adjusting the rotation with this adjustment screw 53, the upper surface 50 of the movable base plate 5o
The spherical tip portion 53a of the adjustment screw 39 is slid onto the top surface S of the movable base plate 50, and the cylindrical portion 33b of the horizontal shaft 33 is in contact with the upper surface S of the movable base plate 50.

However, it will be slid while being in contact with a.

Since the perpendicularity of the upper surfaces 50i and 50a of the movable base plate 50 to the vertical axis 35 is maintained at the required precision, the channel 31 is hardly rotated around the horizontal axis 33 by the sliding movement.

There are no problems with adjustment. Further, since the vertical axis 35 is provided at a position sufficiently spaced from the CCD 2, the CCD 2
During adjustment in the γ direction around the Z axis, the CCD 2 is hardly displaced in the X axis direction, which is the main scanning direction.

Next, position adjustment of the CCD 2 in the Y-axis direction, which is the sub-scanning direction, and the X-axis direction, which is the main scanning direction, will be explained.

A square rod 55.57 is attached to the rear wall 50h of the movable base plate 50 in the Y-axis direction.

Adjusting screws 56.degree. 58 are screwed onto these square rods 55.57. The tip portions of the adjustment screws 56 and 58 are formed into a spherical shape, and the spherical tip portions are connected to the rotating base plate 8.
It is in contact with the front wall 80c of o.

On the other hand, the right side wall 50d of the movable base plate 50 in the X-axis direction
Fitting holes 50f are formed through the left side wall 50e, and each of these fitting holes 50f is connected to a support shaft 64 extending between a right boss 81 and a left boss 82, which will be described later. It is fitted so that it can slide and rotate freely. Further, as particularly shown in FIG. 4, L-shaped plates 59 and 60 are screwed onto the upper sides of the right side wall 50d and left side wall 50e, respectively. One ends of tension springs 61a and 61b are attached to holes 59a and 60a formed at the tips of these L-shaped plates 59 and 6o. Further, as shown in FIGS. 3 and 4, the support shaft 64 includes a right lever 62 and a left lever 6.
3 is rotatably attached. Fitting holes 62a and 63a are formed in the right lever 62 and left lever 63, and these fitting holes 62a and 63a are connected to the support shaft 6.
It is designed to be installed on 4. The right lever 62 and the left lever 63 are arranged on the outside of the right side wall 50cl and the left side wall 50e of the movable base plate 50, respectively, and are inserted into elongated holes 62a formed in their upper arm parts 62d and 63d.
The locking screws 68 and 69 are engaged in the locking screws 63e and 63e, so that the rotation of the right lever 62 and the left lever 63 with respect to the support shaft 64 is restrained, respectively. Note that the locking screws 68 and 69 are attached to the rotating base plate 8.
They are screwed to the right side wall 80a and the left side wall 80b of 0 so as to penetrate in the X-axis direction.

Further, holes 62c and 63c are formed in the middle arm parts 62b and 63b which extend in a direction perpendicular to the upper arm parts 62d and 63d, that is, toward the front wall 80c of the rotating base plate 80. One ends of the aforementioned tension springs 61a and 61b are hung on 63c.

In the state shown in FIG. 4, the tension spring 61a
and 61b are energized.

The movable base plate 50 is about to be rotated clockwise by the biasing force of the tension springs 61a and 61b, but the spherical tip portions 56a and 58a of the adjustment screws 56 and 58 are on the front wall 80c of the rotary base plate 8o. It is designed to be stopped by being pressed against it. The tension spring 61a is extended so that its biasing force generates component forces in the tangential direction and the normal direction around the support shaft 64, whereby the movable base plate 50 is urged against the support shaft 64. , will be held in a fixed position.

Further, as shown in FIG. 6, a lower arm portion 62f is formed below the right lever 62, and a bent portion provided on the lower arm portion 62f forms the right side wall 50d of the movable base plate 50.
is in contact with the lower edge of the

When the COD unit 20 is rotated toward the front to the state shown in FIG. 6 for maintenance or replacement, the tension spring 61a, which is in a predetermined deenergized state, is held so as not to fall off. It has become so. Further, around the fitting holes 62a and 63a formed in the right lever 62 and the left lever 63, circular arc holes 62g, 62h and 63g, 63h are provided so as to face each other. 62g and 63
An adjustment screw 83 is passed through g in a non-contact manner, and locking screws 73 are loosely fitted into the other arcuate holes 62h and 63h.

The fine adjustment mechanism having such a configuration allows precise position movement fine adjustment in the Y-axis direction, which is the sub-scanning direction. That is, by rotating the adjustment screws 56 and 58, the movable base plate 50 is rotated about the support shaft 64 against the tension springs 61a and 61b, thereby positioning the CCD 2 in the Y-axis direction. It has become. At this time, since the rotation center position and the adjustment action position are spaced apart from each other compared to the distance between the rotation center position and the CCD 2, fine adjustments can be made without using a complicated mechanism such as a differential screw. can be set. Note that this adjustment screw 56.
The movement adjustment operation in the sub-scanning direction by 58 is performed by a rotational movement around the support shaft 64, but the CCD 2 is spaced apart from the support shaft 64 and the amount of movement for position adjustment is 1. Since it is ~2 nm, C0D
2, the deviation in the inclination β direction in the sub-scanning direction is extremely small, and there is no problem. Furthermore, when a linear sensor with extremely small pixel dimensions (7 μm×7 μm) is used as in this embodiment, the slight inclination β of the pixel row in the sub-scanning direction does not pose any problem in reading the projected image. Rather C
It is preferable to slightly tilt the CD 2 in the sub-scanning direction with respect to the optical axis, since this prevents the reflected image of the projected image by the cover glass 2b of the CCD 2 from being reprojected onto the pixel row.

Further, fitting holes 81a and 82a are formed through the center portions of the right boss 81 and the left boss 82, which are screwed to the right side walls 80a and 80b of the rotating table plate 8o, respectively. Both end portions of the support shaft 64 are fitted into the matching holes 81a and 82a, and are locked by set screws 81b and 82b.

Further, a compression spring 65 is fitted to the outside of the support shaft 64 . One end portion of this compression spring 65 is attached to the movable base plate 50.
The compression spring 65 is supported on the inner surface of the right side wall 50d, and the other end portion of the compression spring 65 is pressed into contact with a pin 67 fixed through a support shaft 64 through a washer 66 and locked. As a result, the movable base plate 50 is urged toward the right in FIG. 3, that is, toward the right boss 81. On the other hand, the right boss 81 has an adjustment screw 8.
3 are screwed together so that they pass through, and this adjustment screw 83
The spherical tip portion 83a of is in contact with the right side wall 50d of the movable base plate 50. Movable base plate 5 by the compression spring 65
The right side wall 50d of the movable base plate 5o is brought into pressure contact with the spherical tip portion 83a of the g adjustment screw 83 by a moving force of 0. Hence the above! l! By rotating the l adjustment screw 83, the movable base plate 5o is moved in the main scanning direction. The thread pitch of the adjustment screw 83 is 0.5a
n+, and in order to satisfy the position adjustment accuracy of 63.5 μm for the pixel row 2a of the CCD 2, it is only necessary to rotate the adjustment screw 83 with an accuracy of about 45 degrees, which makes the adjustment operation extremely easy. It is supposed to be done. The main scanning direction (X-axis direction) of the CCD 2 by this adjustment screw 83
In the adjustment operation, the position of the CCD 2 is in the sub-scanning direction (Y
axial direction), main scanning tilt direction (α direction), direction around the optical axis (
There is no deviation in either the γ direction) or the Z axis direction. This is configured so that the surface angle between the support shaft 64 and the optical axis of the imaging lens 5 can be adjusted with an accuracy of ±1', and the parallelism of the support shaft 64 to the exposure line 13 of the original image is also ±1'. 1', and that the movable base plate 5o is pressed in the radial direction of the support shaft 64 by the urging force of the tension springs 61a and 61b, and at the same time, the rotary base plate 5o is pressed through the adjusting screws 56 and 58. This is because the position of the movable base plate 50 is maintained by the front wall 80c.

Further, as in this embodiment, the dimensions of the pixel row 2a of the CCD 2 (
The spindle 64 has sufficient spacing (180nu) for
), the positional accuracy of the right boss 81 and left boss 82 supporting the support shaft 64 in the sub-scanning direction (Y-axis direction) is within the normal machining accuracy (for example ±O, la
a), the positional deviation in the sub-scanning direction (Y-axis direction) is about 2 μm for a position adjustment amount of 2 µm in the main-scanning direction X of the CCD 2, and there is no problem in adjustment.

Next, a mechanism for adjusting the perpendicularity of the optical axis of the imaging lens 5 with respect to the original exposure surface shown in FIG. 1, that is, the plane for reading the original 12 with the exposure line 13 will be explained.

As shown in FIG. 3, FIG. 4, and FIG. A hole 96 is formed perpendicular to the axis, and this hole 96
A conical shaft 94 is fitted into the conical shaft 94, and the conical shaft 94 is tightened by a cylindrical female screw 95 so that the front surface M
It is fixed at right angles to l 80 c. Further, the rotating base plate 80 is a base plate 10 having a U-shaped cross section.
The circular arc hole portion 120a of the engagement hole 120 (see FIG. 5(b)) provided in the front wall 100a of the base plate 100 is arranged so as to face the front wall 100a of the base plate 100.
In contrast, the larger diameter side of the conical shaft 94 passes through and projects inside the base plate 100. At this time, the circular arc hole portion 120a of the engagement hole 120 is formed to be smaller than the maximum diameter of the conical portion of the one conical shaft 94 and larger than the minimum diameter, so that the conical inclined surface 94a of the conical shaft 94 engages. It is engaged with the circular arc hole portion 120a of the mating hole 120. As a result, the rotating base plate 80 is made rotatable about the conical shaft 94 with respect to the front wall 100a of the base plate 1o○.

On the other hand, a pedestal 101 is welded to the front wall 100a of the base plate 100 on the right side in FIG.
For the screw hole formed in 1! l! Jm screw 10
2 are screwed together so that they pass through.

The spherical tip portion 102a of the adjustment screw 102 is in contact with the upper surface 90a of the square rod 90 that is welded to the right side wall 80a of the rotating base plate 80. Further, a stepped pin 9 is provided on the left side portion of the front wall 100a of the base plate 100 in FIG.
3 are erected, and stepped pins 91 are erected on the left side wall 80b of the rotating base plate 80, and tension springs 92 are installed between the stepped pins 93 and the stepped pins 91. is spread across the board. As a result, the base plate 10
The rotating base plate 8o is connected to the conical shaft 94 with respect to the front wall 100a of
It is urged to rotate around the third diagram around , and
The upper surface 90a of the square bar 9o welded to the right side wall 80a of the rotating base plate 8o is the spherical tip portion 10 of the adjustment screw 102.
2a, and the rotating base plate 80 is stopped.

At this time, the conical shaft 94 is pressed downward perpendicularly to the conical shaft 94, but as described above, the conical inclined surface 94a of the conical shaft 94 By engaging with the conical shaft 94, the conical shaft 94 receives a component force directed to the left in FIG. 5, and this component force presses the rotating base plate 80 toward the base plate 100. Also, the base plate 1
On the front g1ooa of 00, three circular pedestals 100f are formed on the circumference centered on the conical axis 94 at an even pitch of approximately 120°, and these circular pedestals 100
The outer surface of the front wall 8°C of the rotating base plate 80 is brought into contact with the upper surface f, and the rotating base plate 8o is supported at three points, so that the rotating base plate 8o can be rotated stably. It has become. Further, in the front wall 80c of the rotating plywood 80, three elongated holes 8 are formed at equal intervals of approximately 120° on the circumference around the conical shaft 94.
4,85,86 are formed, and these elongated holes 84,
Set screws 86, 87°88 passing through 85, 86 are attached to the base plate 1.
It is screwed onto the front wall 100a of 00 to fix the rotating base plate.

Therefore, if the adjustment screw 102 is rotated with the pressure screws 86, 87, and 88 loosened, the rotating base plate 80 is rotated about the conical shaft 94, and the optical axis of the imaging lens 5 is rotated at right angles to the optical axis of the imaging lens 5. will be adjusted.

In the perpendicularity adjustment operation of the optical axis using the adjustment screw 102, the position of the CCD 2 is adjusted in the main scanning direction (X-axis direction), the sub-scanning direction (Y-axis direction), the main scanning tilt direction (α direction), and the direction around the optical axis. No deviation occurs in either the γ direction or the Z axis direction. Further, the three-point support structure of the rotating base plate 80 prevents the rotating base plate 8o from deforming.

In the perpendicularity adjustment mechanism in the sub-scanning direction between the optical axis of the imaging lens 5 and the original image exposure surface, as shown in FIGS. 14, 15 and 16, the base plate 100
is screwed onto the front wall 200a of the base 200, and three circular pedestals 203 are welded to the front wall 200a, and a left side plate is welded to the left and right ends of the pedestals 203, respectively. A left main shaft 215 and a right main shaft 217 are attached to the right side plate 213 and the right side plate 216 so as to be coaxially arranged. Two shafts 214 are provided at positions symmetrical to the left main shaft 215 on the left side plate 213 so that they are parallel to the left main shaft 215 and their axes are arranged on the same plane. The left support frame 230 and the right support frame 231, which are provided as immovable members with respect to the original exposure line 13, have the base 200 attached to the left main shaft 215.
A left support plate 218 and a right support plate 225, which are rotatably supported around the right main shaft 217, are welded to each other.

A recess 218a is formed in the center of the left support plate 218, and a bottom surface 21 of the recess 218a
A bearing portion 218b having an arcuate cross section is recessed in the center portion of 8f. The left main shaft 21 is attached to this bearing portion 218b.
5 is fitted.

Further, the left main shaft 21 is located at the bottom surface 218f of the recess 218a.
A square bar 219 for positioning 5 is fixed by two setscrews 220. - Grooves 21 on the right and left main shafts 215
5a is formed in an annular shape, and the square rod 219 is brought into contact with the groove bottom 215b of the annular groove 215a, so that the left main shaft 215 is positioned immovably in the left and right main axis direction, that is, in the main scanning direction (X-axis direction). It is becoming regulated.

Also, a set screw 22 is screwed onto the square rod 219.
1 is pressed against the groove bottom 215b of the groove 215a.

Furthermore, grooves 318c and 218d are formed in the upper and lower end portions of the left support plate 218 to accommodate the shaft 214 in a loosely fitted state.

Adjustment screws 222 and 223 to press the shaft 214.
are screwed onto the upper and lower end portions of the left support plate 218, respectively. By rotating the adjusting screws 222 and 223, the left support plate 218 is rotated about the biaxial shaft.

Further, a bearing portion 225a having an arcuate cross section is recessed in the center portion of the right support plate 225.
A right main shaft 217 is fitted into the main shaft 217 . Also, the right support plate 22
5 has a corner 4$2 for positioning the right main shaft 217.
26 is fixed by two set screws 226, and the tip of the set screw 228 screwed onto the square bar 226 is pressed against the surface of the right main shaft 217.

In FIG. 15, the optical axis of the imaging lens 5 is the axis 214.
The imaging lens 5 is set parallel to the straight line connecting the axis of the left main axis 215 and the left main axis 215, and extends in the sub-scanning direction through the left main axis 215 and the right main axis 217.
The optical center of the imaging lens 5 is arranged, and the optical axis position of the imaging lens 5 is arranged near the left and right axes. In such a configuration, if the adjusting screws 222 and 223 are rotated, the optical axis of the imaging lens 5 is rotated integrally with the base 200, and the inclination in the sub-scanning direction (Y-axis direction) is adjusted. It will be fine-tuned to v8.

In this adjustment operation, the angle between the optical axis of the imaging lens 5 and the original exposure surface in the sub-scanning direction is finely adjusted. axial direction) or in the inclination direction (α direction) of the main scanning direction. Further, after adjusting the inclination of the optical axis of the imaging lens 5 in the sub-scanning direction, the set screw 221.
228 and adjusting screws 222, 223
0 is fixed in position, and therefore the position of the imaging lens 5 is fixed.

Next, lens unit 1-300 and CCD unit 2
The movement adjustment mechanism in the optical axis direction of the lens will be described.

Next, Lens Units l-300 and CCD unit 2
The following describes the movement adjustment structure i in the optical axis direction of the lens.

In FIGS. 1, 2, 3, 4, and 14, the left support frame 230 and the right support frame 230 are provided as immovable members with respect to the exposure line 13 of the original image, as described above. With respect to the frame 231, the base 200 is aligned with the exposure line 1.
A left main shaft 215 and a right main shaft 2 which are parallel to and coaxial with 3.
This base 20 is rotatably supported by a base 17.
Fitting holes 2 are provided in the upper wall 200b and lower wall 200c of 0.
01 and 202 are formed so as to face each other. In these fitting holes 201 and 202, the left main shaft 231
and the support shaft 11 at right angles to both axes of the right main shaft 217.
3 is inserted. On the other hand, the upper wall 10 of the base plate 100
0b and the lower wall 100c have both fitting holes 201,
Elongated hole 1 extending long in the sub-scanning direction at a position corresponding to 202
11.degree. 112 are formed respectively, and both upper and lower end portions of the support shaft 113 are fitted into these elongated holes 111 and 112. Further, retaining rings 114 are respectively engaged on the upper and lower sides of the upper wall 100b and the lower wall 100C of the upper plate 100 of the support shaft 113, so that the support shaft 113 and the base plate 100 are fixed to the imaging lens 5. It is supported so that it can slide in the optical axis direction. At this time, the base plate 100 is movable in the sub-scanning direction (Y-axis direction).

In addition, it remains stationary in the main scanning direction (X-axis direction).

Furthermore, among the three circular pedestals 203 welded to the front wall 200a of the base 200, two circular pedestals 203 are placed apart from each other by a predetermined distance on a line parallel to the axis of the support shaft 113. Along with the remaining one circular pedestal 20
3 is arranged on a line parallel to the axes of the left main shaft 215 and right main shaft 217. The surface portions of these three circular pedestals 203 are formed so as to be arranged in the same plane, and are each formed with a female thread portion 203b into which a screw 104, which will be described later, is screwed. On the other hand, in the front wall 100a of the base plate 100, there are three vertically long elongated holes 103 at positions corresponding to the three circular pedestals 203.
The screws 104 pass through each of these elongated holes 103. A compression spring 106 is attached to the outside of the screw 104, and this compression spring 106
A tube 105 is attached to the outside of the tube. compression spring 106
One end portion of the compression spring 106 is pressed against the screw head of the screw 104 through a washer 107, and the other end portion of the compression spring 106 is pressed against the base plate 100 through a washer 108. As a result, the base plate 100 is pressed toward the circular base 203, and the base plate 100 is moved along the support shaft 113 while being pressed against the circular base 203 by the urging force of the compression springs 106 at three locations. It is made slidable in the direction of the lens optical axis. At this time, the base plate 100 remains stationary in the sub-scanning direction.

Further, a square rod 109 is screwed to the right end of the upper wall 100b of the base plate 100 near the support shaft 113, and an adjustment screw 110 is screwed to pass through the square rod 109. Spherical tip portion 11 of the adjustment screw 110
0a passes through a large diameter hole (not shown) formed in the base plate 10 and abuts on the upper wall 200b of the base 200.

In this embodiment, one base plate 100, a rotary base plate 8o attached thereto, and further a lens unit 300, a CCD unit 20, and a CCD unit 20 attached to the rotary base plate 80 are shown.
5 due to the weight of the CD base plate unit 30, support shaft 64, etc.
The force that presses and slides the base plate 100 downward along the support shaft 113 is applied to the base plate 100 by the compression of the three compression springs 10.6.
The friction resistance force between the front wall 100a of the circular base 203 and the front surface 203a of the circular pedestal 203 is larger than that of the front wall 100a of the circular base 203.
In particular, no spring is used to press and bias the base plate 100 downward. However, if necessary, a compression spring may be inserted into the support shaft 113, for example, between the lower wall 100c of the base plate 100 and the lower wall 200C of the base 200.

In such a configuration, by rotating the adjustment screw 110, the base plate 100 is finely adjusted and moved along the support shaft 113 while being in contact with the circular base 203. Therefore, by moving the adjusting screw 110 back and forth, the lens unit 300 and the CCD unit 20 can be finely adjusted in the direction of the lens optical axis without causing any mutual positional deviation. And with this, exposure line 1
Fine adjustment of the distance between CCD 3 and CCD 2, that is, the conjugate length (L in FIG. 2) at a predetermined projection magnification, can be easily and accurately performed. Moreover, during such adjustment, the imaging lens 5 and C0D2 are rotated in the main scanning direction (X-axis direction), the sub-scanning direction (Y-axis direction), the u-turn direction (γ direction) around the lens optical axis, No deviation occurs in the inclination direction (α direction) in the main scanning direction and the inclination direction (β direction) in the sub-scanning direction.

Next, the light shielding and dustproof seal structure of the CCD 2 will be explained.

3 and 5, a seal body 31 is attached to the lower part 301d of the lens holder 301 of the lens unit 300.
An upper plate 311 which is adhesively fixed to the top plate 311 is fitted.

The upper plate 311 is formed with a bent portion 311a for positioning in the main scanning direction and the sub-scanning direction. On the other hand, the lower side of the seal body 310 is bonded to a lower plate 312, and this lower plate 312 is formed with a notch 312a that engages with two countersunk screw pins 32 that screw the CCD unit 20 into the channel 31. has been done. The above seal body 31
0 is attached and positioned so as to shield the peripheral area outside the imaging optical path of the imaging lens 5 between the lens holder 301 and the metal plate 21 that adhesively holds the C0D 2.

The seal body 310 is made of a soft foamed resin having fine mesh and light-shielding properties and air permeability formed into a rectangular tube shape, and its elastic force allows the lens holder 301 and the metal plate 2 to be attached to each other.
1 through an upper plate 311 and a lower plate 312.

No gaps are formed between the upper plate 311 and the lens holder 301 and between the lower plate 312 and the metal plate 21. With such a seal body 310, the CCD 2
External light that would degrade the image reading signal is blocked, and the adhesion of dirt, dust, etc. to the CCD 2 is prevented.

Further, the sealing body 310 is made of a material and having a shape and dimensions that do not impair air permeability, so that the image reading function of the CCD 2 is sufficiently prevented from being inhibited or degraded. Furthermore, the hardness and size of the seal body 310 are such that the lens holder 301 or the metal plate 21 will not be deformed or misaligned with each other due to the elastic force of the seal body 310, and the lens holder 301 and the metal plate It is set to such an extent that it is possible to separate from between 21 and 21. Therefore, the sealing body 310 in which the upper plate 311 and the lower plate 312 are vertically bonded can be easily attached and detached between the lens holder 301 and the metal plate 21, and the upper plate 31
1 and the lower plate 312, the mounting position of the metal plate 21 does not shift when adjusting the position of the metal plate 21 relative to the lens holder 301, and the flexibility of the seal body 301 prevents the lens from shifting. Holder 301. This prevents excessive force from being applied to the metal plate 21.

In the cooling system shown in FIG. 5(,), the air that is forced into the air by the blower 206 is filtered by the dust filter 208 attached to the duct 2o7, and then filtered to the base. flowed into the stand 200,
From the square hole 205 of the base 200 to the square hole 100g of the base plate 100
The liquid passes through the square hole 80a of the rotating base plate 80 and is sprayed toward the sealing body 310, the lower part of the CCD 2, and the PCB-1'22. This blower 206
The air blowing action is controlled based on a temperature detection signal of the CCD 2 emitted from a thermistor 25 that is in contact with and bonded to the back surface of the CCD 2.

With such a cooling device for the CCD unit 20, C
This prevents expansion and deformation of the CCD 2 due to heat generated from the CD 2 itself or the PCB-122 soldered to the CCD 2. This prevents image reading abnormalities from occurring, and also prevents the electronic components on the PCB-122 from expanding or deforming. Malfunctions due to heat generation are also prevented.

Although the CCD 2 installed in the document reading device is designed to prevent dust such as dust from adhering to the surface of the cover glass 2b, it may interfere with normal reading during long-term use. Since dirt and dust may adhere to the surface, it is desirable to clean it as necessary. Furthermore, it is desirable that the CCD 2 be constructed so that it can be easily replaced if it breaks down or its performance deteriorates for some reason.

Therefore, in this embodiment, the mounting member of the CCD 2 is made rotatable in the sub-scanning direction.

A configuration is adopted in which the CCD 2 is retracted out of the imaging optical path in the form of a CCD unit 20 that is integrally formed with a metal plate 21 that is a holding member thereof, and this makes it easy to attach and detach the CCD 2 to the member. There is. Further, when simply cleaning the CCD 2 without replacing it, the CCD unit 2o is configured to expose the CCD unit 2o at an angle to the front, making the cleaning operation extremely easy. Furthermore, when cleaning, and even when replacing the CCD unit 2o, the CC
The position of the mounting member D2 is configured so that it can be accurately returned to its original position by the biasing force of an adjustment screw and a spring, and it is extremely easy to make fine adjustments due to dimensional variations in the CCD unit 20. It is configured to be easy to use.

That is, as shown in FIGS. 3, 4, and 6, the tip of the screw 68 screwed into the right side wall 80a of the rotating base plate 80 is connected to the upper arm 62d of the right lever 62. Although the right lever 62 is retracted to the position where it is removed from the elongated hole 62e, the right lever 62 is rotated around the support shaft 64 in the direction shown in FIG. 6 by the biasing force of the tension spring 61a. A bent portion of the lower arm portion 62f of the movable base plate 50 is brought into contact with the lower edge of the right wall 50d of the movable base plate 50.

As a result, the movable base plate 50 and the support shaft 6 of the right lever 62
The relative position around 4 is made stable. Similarly, when the screw 69 screwed into the left side wall 80b is removed from the elongated hole 63e of the upper arm 63d of the left lever 63, the bent portion of the lower arm 63f of the left lever 63 is attached to the movable base plate 50.
As a result, the relative positions of the movable base plate 50 and the left lever 63 around the support shaft 64 are brought into a stable state.

In this state, as shown in FIG.
The movable base plate 50 on which the D-Units I-20 is attached can rotate integrally with the right lever 62 and the left lever 63 to a point outside the projection optical path of the imaging lens 5. The circular hole 6 of the right lever 62 is connected to the screws 73 and 74 that are screwed into the right boss 81 and the left boss 82, respectively.
2h and one end of the arcuate hole 63h of the left lever 63 are brought into contact with each other to be regulated. In this state, the COD unit 2o is exposed at the front of the apparatus, and cleaning of the CCD 2 and replacement and attachment/detachment of the COD unit 20 are extremely easy. In addition, in this state, the arcuate hole 62g of the right lever 62 does not come into contact with the adjustment screw 83 that cooperates with the compression spring 65 to position the movable base plate 5o on which the COD unit 20 is attached in the main scanning direction. The position and size of the arcuate hole 62g are set so as to prevent the adjustment screw 83 from being displaced or deformed due to excessive force being applied to it. . At this time, the movable base plate 5
The holding member (channel 31 in FIG. 3) of the COD unit 20, which is held so as to be adjustable in position with respect to the movable base plate 50, is maintained in a completely unchanged state with respect to the movable base plate 50.

After completing the necessary work such as cleaning and replacing the CCD 2 and COD unit 20, the movable base plate 50 is rotated back to its original position. That is, if the right lever 62 and the left lever 63 are locked in predetermined positions by screws 68 and 69, respectively, the tension springs 61a and 6
The movable base plate 50 is rotated around the support shaft 64 by the biasing force of the movable base plate 1b. The plate 5o is returned to its original position in a state where it is accurately positioned. Also at this time, the movable base plate 50
The right side wall 50d is also brought into contact with the adjustment screw 83 at its original position, so that its position in the main scanning direction can also be accurately returned to its original position.

In the image reading virtual display in the embodiment of the present invention, the position adjustment of the COD with respect to the imaging lens, the imaging lens 5. A position adjustment mechanism that uses the steps of a screw is used to adjust the position of the CCD2. That is, in this embodiment, a means for pressing the male thread and the female thread in the radial direction is used in order to prevent problems in fine adjustment due to play in the axial and radial directions of the screw.

As shown in FIGS. 17 and 18, the square bar 3
8 and the movable base plate 50 are urged toward each other by a tension spring or gravity, and an adjustment screw 39 is screwed into a female thread 38a formed in the square bar 38. The hemispherical tip portion 39a of this adjustment screw 39 is in contact with the upper surface 50i of the movable base plate 50.

The mutual positions of the square rod 38 and the movable base plate 5o are determined by the cooperation of tension springs or gravity. Also, a female thread 38 formed on the square bar 38
A female thread 73 is formed in a direction perpendicular to the screw axis of a, and has a diameter equal to or slightly smaller than the root diameter of this female screw 73, and a length approximately equal to the root diameter of the female screw 73. A cylindrical brake element 71 made of nylon is fitted into the female thread 73. A set screw 72 is screwed into the female thread 73 from behind the brake element 71, and a planar tip 72a of the set screw 72 presses the brake element 71.

The planar tip 72a of the set screw 72 is connected to the brake member 71.
When the set screw 72 is screwed in more strongly from the state in which it is in contact with the nylon brake element 71, the tip part of the nylon brake element 71 is pressed against the adjustment screw 39 while undergoing compressive deformation, and the tip part 71a of the brake element 71 becomes: A. As it bites into the threads and valleys of the setting screw 39, the peripheral surface 71b of this brake 71 in contact with the female thread 73 also undergoes plastic deformation so as to bite into the threads and valleys of the female thread 73. becomes. In this state, the male thread of the adjusting screw 39 presses the female thread 38a in the radial direction, and the axial center of the adjusting screw 39 is maintained slightly deviated from the axial center of the female thread 38a. The shaft center position can be rotated without shifting due to rotation. Therefore, the tip 39a of the adjusting screw 39 is not moved in the radial direction of the screw. Female thread 38a
The relative position between the square bar 38 and the movable base plate 50 is adjusted by the steps of the adjusting screw 39 when rotating the adjusting screw 39, which has a male thread that engages with the adjusting screw 39. The contact position of the tip end 39a of the adjusting screw 39 with respect to the upper surface 50i of the movable base plate 50 does not shift due to play in engagement with the screw 38a.

Furthermore, when the nylon brake 71 is plastically deformed as described above, elastic stress is generated in itself, so the brake 71
1 and the setscrew 72 are prevented from unintentionally loosening. Further, the braking force applied to the adjusting screw 39 by the suppressing force of the brake element 71 does not change regardless of whether the adjusting screw advances or retreats, and can be further adjusted as necessary.

In such a configuration, after the relative position between the movable base plate 50 and the square bar 38 is adjusted by moving the adjustment screw 39 back and forth, the set screw 72 is further screwed in, thereby further pressing and deforming the brake element 71. Adjustment screw 39 is female thread 38
It is immovably locked with respect to a. In this case, the adjustment screw 39 will not be displaced from the female thread 38a by screwing in the set screw 72. Therefore, no other fastening means is required for locking the adjustment screw 39 to the female thread 38a.

If the adjusting screw 39 has been rotated for some reason and it becomes necessary to readjust the mutual positions of the movable base plate 5o and the square bar 38, loosen the set screw 72 slightly and adjust the position of the brake 71 relative to the adjusting screw 39. Reduce the pressing force. By doing this, the adjustment screw 39 can be rotated with its axial center position maintained at a predetermined position by the required pressing force, and there is no damage to the threaded portion of the adjustment screw 39. Also, no indentation is caused, and therefore the smooth rotation of the adjusting screw 39 is not hindered in any way.

Such an adjustment screw 39. Square bar 38. Upper surface 501 of movable base plate 50. The position adjustment device constituted by the brake 71 and the set screw 72 is similarly employed in other position adjustment devices, that is, position adjustment devices using adjustment screws 53, 513, 58°, 102, 110, 83.

[Effects of the Invention] As described above, according to the present invention, in positioning the photoelectric conversion element, adjustment of the main scanning direction of the pixel row, adjustment of the sub-scanning direction, adjustment of the lens optical axis direction, and adjustment of the lens optical axis are performed. Adjustments around axes in orthogonal directions can be accurately and easily fine-tuned without mutual interference.

[Brief explanation of the drawing]

Fig. 1 is an external perspective view showing the main parts of the optical system of an apparatus in an embodiment of the present invention, and Fig. 2 shows a set of imaging lenses and C
FIG. 3 is an explanatory front view showing a set of CCD reading units, and FIGS. 4 and 5 (a) show the CCD shown in FIG. 3. 5(b) is a front explanatory view showing the shape of the hole provided in the base plate; FIG. is C
FIG. 7 is a plan view showing the positioning and fixing structure of the CCD, and FIG. 8 is a cross-sectional view taken along line A-A' in FIG. 7. 9 is an explanatory plan view showing another embodiment of the CCD positioning and fixing structure, FIG. 10 is an explanatory cross-sectional view taken along the line B-B' in FIG. 9, and FIG. 11 is an explanatory plan view showing the CCD connection. FIG. 12 is an exploded perspective view showing a CCD fine adjustment structure, and FIG. 13 is a focus adjustment mounting structure for an imaging lens. 14 is a front explanatory view showing a state in which the reading unit shown in FIG. 3 is removed from the base;
Fig. 15 is an explanatory cross-sectional view taken along the line A-A' in Fig. 14, Fig. 16 is an explanatory cross-sectional view taken along the line B-B' in Fig. 14, and Figs. 17 and 18 are the adjustment screws. FIG. 1.2, 3...CCD, 4,5,6...imaging lens. 12... Document, 13... Exposure line, 15... Reading unit, 20... CCD unit 1-131...
Channel, 33...Horizontal axis (first spindle), 35...
・Vertical axis (second support axis), 50...Movable base plate, 64...
・Third pivot. -q Kuni Knee β Form 40 Curse 74 Kuni? Shape 16 Figure 47 Figure 4 Figure 173

Claims (1)

[Claims] 1. A document image is projected onto a photoelectric conversion element by an imaging lens, and the document image is read photoelectrically by relatively moving the document image and the photoelectric conversion element in a sub-scanning direction. In the position adjustment mechanism of an image reading device. a first support shaft having an axis extending in the optical axis direction of the imaging lens; a second support shaft having an axis extending in a direction perpendicular to the optical axis direction of the imaging lens; are held between each other so as to be rotatable around the axis of the other side, and the photoelectric conversion element is held with respect to either one of the first support shaft and the second support shaft. , the photoelectric conversion element is provided with rotation fine adjustment means for rotating the photoelectric conversion element around the first support shaft and the second support shaft, and the first support shaft and the second support shaft The supporting shaft is relative to the third supporting shaft extending in a direction perpendicular to both supporting shafts.
A position adjustment mechanism for an image reading device, characterized in that the mechanism is slidably and rotatably mounted. 2. In the position adjustment mechanism for an image reading device according to claim 1, the photoelectric conversion element is provided with rotation fine adjustment means for rotating the photoelectric conversion element around a third support shaft. A position adjustment mechanism for an image reading device, characterized in that: 3. In the position adjustment mechanism for an image reading device according to claim 1, the photoelectric conversion element is provided with a sliding fine adjustment means for sliding the photoelectric conversion element along the third support shaft. A position adjustment mechanism for an image reading device, characterized in that: