JP2002171387A - Image reader - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide technique concerning the fitting structure of a CCD unit which realizes a radiation effect to a CCD line sensor so that picture deterioration such as discoloration, is avoided and the number of components, the assembling man-hours of the CCD unit and the production cost are reduced. SOLUTION: A reading substrate 12 is fixed and held by a holding member 11 to improve the rigidity of the substrate 12 itself and a thermally-conductive rigid member is used for the member 11. The member 11 pressurizes and holds the CCD line sensor 10 in a vertical direction by an elastic member provided on one face to improve the rigidity also of the sensor 10. An aperture part 19 is formed. Thus, constitution tough against disturbance such as the thermal expansion, vibration, etc., of the sensor 10 causing picture deterioration such as discoloration is obtained. The CCD unit 13 avoids the use of a radiation panel 17, a socket 18 and a spacer so that the number of the components, the cost and the assembling man-hours are reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image reading apparatus such as a digital copying machine, an image scanner, and a facsimile provided with a reduction optical system using a CCD line sensor as a reading element.

[0002]

2. Description of the Related Art In recent years, with the development of digital technology, digital copiers and the like have realized higher speed and higher accuracy. Accompanying this, the reading speed of the image reading unit has been increased, and the scan clock of pixels in the CCD line sensor used in these devices has also been increasing in speed.
Since the calorific value of the line sensor is also increasing, sufficient consideration is required.

In a digital copying machine, in a color copying machine, a CCD line sensor has a three-line configuration of RGB, and when an image forming unit has only one photoconductor, an image reading unit is also one. Four document reading scans must be performed in one copy job.

[0004] At this time, if different disturbances such as vibrations are intervened during each original reading scan, different points are read in each of the RGB lines, causing serious image deterioration such as color misregistration. . Further, even when the original is scanned once, if the CCD line sensor is subjected to disturbance such as vibration, serious image deterioration such as image fluctuation is caused.

In an image reading apparatus having a conventional optical system, a copy original placed on an original platen glass is illuminated by illumination.
A second mirror and a third mirror mounted on a unit that reflects reflected irradiation light by a first mirror mounted on the same unit as the illumination and moves at a speed of に in the same direction as the movement direction of the unit To form an image on a CCD line sensor via an imaging lens.
In this optical system, the CCD is
It was necessary to adjust the position so that the reading axis of the line sensor was aligned with the optical axis.

In a CCD unit equipped with a CCD line,
CCD line sensor 10 for reading a copy original as shown in FIG.
And a reading board 12 for driving the CCD line sensor, a fixing member 11 for fixing the CCD line sensor 10, a leaf spring, and a heat radiating plate 1 for radiating heat generated from the CCD line sensor 10 into the air.
7, and a spacer for securing the distance between the CCD line sensor 10 and the reading substrate 12 and fixing the reading substrate 12. On the reading board, a socket 18 for insertion fitting with a lead 10c extending from the CCD line sensor 10 was mounted.

[0007]

However, in the case of the above-described prior art, the following problems have occurred.

In the CCD line sensor 10, a load caused by disturbance such as thermal expansion or vibration due to heat generation causes the lead 10c to float or come off, and a member for backing up the reading substrate is also required for the countermeasure. Was. Further, the floating of the lead 10c causes a shift with respect to the optical axis of the CCD line sensor 10, and causes a problem such as a change in one-side magnification. Further, if the leads 10c are not sufficiently fixed, disturbances such as vibrations may affect the CCD line sensor 10 and the reading substrate 12 to cause color shift and image fluctuation of the read image.

On the other hand, the socket 18 is provided with a lead 10c.
For example, when a plurality of sockets 18 are used, the number of parts and cost increase, and the number of assembling steps also needs to be increased in order to adjust the heights and positions. .

The present invention has been made to solve the above-mentioned problems of the prior art, and an object thereof is to provide a CCD.
It is an object of the present invention to provide a technology relating to a CCD unit mounting structure capable of reducing a heat radiation effect on a line sensor, eliminating image deterioration such as color misregistration, reducing the number of components and the number of assembly steps, and reducing the cost associated therewith.

[0011]

The CCD comprises: a reading substrate formed by soldering the CCD line sensor on a printed circuit board; and a holding member that holds the reading substrate on one surface and the CCD line sensor on the back surface. Unit and the CCD
Provide an imaging lens facing the line sensor and an adjustable lens unit, and displace the CCD unit and the imaging lens relatively to align the optical axis of the imaging lens with the reading line of the CCD line sensor. In the image reading apparatus provided with the reading optical system described above, a holding member of the CCD unit is provided between the CCD line sensor fixed by fixing means and the reading base, and the CCD line sensor is pressed against the holding member. It is characterized by being retained.

The holding member has one surface to which the surface to be read of the CCD line sensor is abutted, and the other surface fixed to the reading substrate. An elastic member is provided on one surface of the holding member.

The elastic members are provided at both ends in the axial direction of the CCD line sensor, and at least one end of the CCD line sensor is arranged such that a side surface of the CCD line sensor is perpendicular to a positioning member protruding from one surface of the holding member. Is characterized in that position control is performed by energizing.

[0014] On the bonding surface between the holding member and the reading substrate,
An opening as a heat radiating mechanism is provided on a surface where a holding member used for a heat radiating purpose of the CCD unit is in contact with a purpose of avoiding a lead connecting the CCD line sensor and the reading substrate.

As a result, the rigidity of the reading substrate itself is increased by fixing and holding the reading substrate to the holding member, and a rigid member having high thermal conductivity is used as the holding member, and the holding member is provided on one surface. The rigidity of the CCD line sensor is also increased by urging and holding the CCD line sensor in the vertical direction by the elastic member provided, and the CCD line sensor and the reading substrate are connected to the bonding surface between the holding member and the reading substrate. Thermal expansion, vibration, etc. of the CCD line sensor that causes image deterioration such as color misregistration by providing an opening as a heat radiation mechanism on the surface where the holding member used for the heat radiation of the CCD unit is in contact with the use to avoid the lead Obtain a configuration that is strong against external disturbances.

The CCD unit does not use a heat radiating plate, a socket and a spacer used in the prior art, so that the number of components and the cost can be reduced, and the number of assembling steps can be reduced.

[0017]

Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. However, the dimensions of the components described in this embodiment,
The materials, shapes, relative arrangements, and the like are not intended to limit the scope of the present invention only to them unless otherwise specified.

Further, in the following drawings, the same reference numerals are given to members described in the drawings used in the above description of the prior art and members similar to the members described in the drawings described above.

An image reading storage according to an embodiment of the present invention will be described with reference to FIGS.

FIG. 1 is a diagram showing the overall configuration of an image reading device in a digital color copying machine. In an image reading apparatus having an optical system, a copy original placed on a platen glass 1 is illuminated by illumination 2, and reflected illumination light is reflected by a first mirror 3 mounted on a first optical unit 4 same as the illumination. The second mirror 5 mounted on the second optical system unit 7 moves at a speed of １ ／ in the same direction as the direction of movement of the first optical system unit 4 (horizontal direction in the figure). In this optical system, the light is further reflected in the 90 ° direction by the third mirror 6 and is imaged on the CCD line sensor 10 through the imaging lens 8. Are adjusted so that the optical axes coincide.

A CCD line sensor 10, a holding member 11 for fixing the CCD line sensor 10, and a reading substrate 12 are mainly constituted.
The adjustment of the CCD unit 13 is performed after the unit is assembled.

Each elastic member (for example, a leaf spring 14) and a pin-shaped positioning member 15 protruding from one surface of the holding member 11 are provided on one surface of the holding member 11 at both axial ends of the CCD line sensor 10. Have been.

As shown in FIG. 4, the CCD line sensor 10 is urged toward the holding member 11 by leaf springs 14a and 14b provided at both ends in the axial direction. And
The leaf spring 14c at one end in the axial direction urges the CCD line sensor 10 on the holding surface in the other axis end direction (right direction in the figure) and in the width direction (down direction in the figure), and moves toward the other axis end direction. Are locked by the positioning member 15a, and the bias in the width direction is locked by the positioning member 15b.

Further, the leaf spring 14d urges the CCD line sensor 10 on the holding surface in the width direction (downward in the figure), and the urging force is locked by the positioning member 15b via the CCD line sensor 10. Have been.

As described above, one axis end (left end) of the CCD line sensor 10 is urged in the width direction and the axial direction, and the other end (right end) is urged only in the width direction. As a result, between the leaf springs 14a to 14d on one surface of the holding member 11,
Just by inserting the CCD line sensor 10, each leaf spring 14a
Accurate positioning of the CCD line sensor 10 is realized by the biasing force of the positioning members 15a to 15d and the urging force of the positioning members 15a to 15d.

As described above, since the CCD line sensor 10 and the holding member 11 are not bonded and fixed, even if the CCD line sensor 10 or the holding member 11 is thermally deformed,
Damage can be prevented.

As the holding member 11, a rigid member having high thermal conductivity such as aluminum is used, and the heat radiation of the CCD unit is taken into consideration so as to secure a space and a positional relationship between the holding member 11 and the reading substrate 12. The opening 19 was provided as a heat radiation mechanism used in the above-mentioned application. This opening 19
Is used to guide the lead 10c extending from the CCD line sensor 10 and connected to the reading substrate 12 to the back surface of the surface in contact with the CCD line sensor 10 to avoid the lead 10c. At this time, the CCD line sensor 10 is guided so as not to be deformed because it has a supporting portion that can always support the back surface of the CCD line sensor 10.

Further, it has a mounting portion for fixing the holding member 11 and the reading substrate 12, and here, for example, a tap for screw fitting is cut.

Next, a lead 10c extending from the CCD line sensor 10 is inserted into a hole formed in the reading substrate 12 in advance, and the reading substrate 12 is held so as not to warp. The reading substrate 12 is fixed to the holding member 11 by screws 16 for fitting. Thereafter, the lead 10c of the CCD line sensor 10 protruding from the fixedly held reading substrate 12 is fixed by a conductive adhesive member such as solder.

When a load is applied to the reading substrate 12 so as to deform the copy original into a concave shape, the deformation is prevented because the CCD line sensor 10 is guided by the holding member 11. Conversely, when a load is applied to the reading substrate 12 such that the reading substrate 12 is deformed in a convex shape, the reading substrate 12
As a result, deformation is prevented. Therefore, the CCD line sensor 10 and the reading substrate 12 assembled in the CCD unit 13 can have higher rigidity than the rigidity of the single unit.

The assembled CCD unit 13 is adjusted so that an image is formed on a CCD reading line.
It is fixed to a lens unit 9 on which the imaging lens 8 is mounted by an adhesive member such as solder.

According to such a configuration, even if heat is generated from the CCD line sensor 10 and the reading substrate 12, the holding member 1
1, the heat radiation effect is obtained, and the uniformity of the heat distribution of the CCD line sensor 10 can be ensured.

Further, the CCD unit 13 having a secured rigidity
Is strong against stress that causes deformation and also against low-frequency vibration that induces color shift of the copied image, resulting in a structure that is strong against disturbances such as thermal expansion and vibration. This can greatly contribute to forming a copy image with a small number of images.

Further, the holding member 11 and the reading substrate 12 which are conventionally engaged with the CCD 18 by fitting the CCD line sensor 10 and the reading substrate 12 with the socket 18 or through the spacer.
As compared with the fitting of the above, it is possible to contribute to the reduction of the number of assembling steps and the improvement of workability, and the cost reduction is also realized.

[0035]

As described above, according to the present invention, in a CCD unit constituting an image reading apparatus, in which a CCD line sensor is directly soldered to a reading substrate, a guide, a heat radiating plate, and a reading substrate of the CCD line sensor are provided. By providing a CCD line sensor holding member that has various functions as well as a guide, a CCD line sensor and a spacer for the reading substrate, and a fixing of the reading substrate, a unit having higher rigidity can be formed.
It becomes strong against disturbances such as vibrations, so that the problem of color misregistration can be solved, and deformation due to heat generated from the inside can be eliminated, and the problem of variation in half magnification can also be solved.
Furthermore, the number of parts is reduced compared to conventional CCD units, which leads to cost reduction. In addition, a heat sink and spacers are not required in the assembly process, and sockets are not required, so that various lead-type CCD line sensors can be supported, leading to a reduction in the number of assembly steps.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating an overall configuration of an image reading apparatus.

FIG. 2 is a plan view illustrating a configuration of a CCD unit.

FIG. 3 is a plan view of a CCD line sensor.

FIG. 4 is a front view of the CCD unit.

FIG. 5 is a plan view showing a configuration of a conventional CCD unit.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Original platen glass 2 Lighting 3 First mirror 4 First optical system unit 5 Second mirror 6 Third mirror 7 Second optical system unit 8 Imaging lens 9 Lens unit 10 CCD line sensor 10a Cover glass 10b CCD line sensor body 10c Lead 11 Holding member 12 Reading board 13 CCD unit 14 Leaf spring 14a-d Leaf spring 15 Positioning member 15a-c Positioning member 16 Screw 17 Heat radiating plate 18 Socket 19 Opening

 ────────────────────────────────────────────────── ─── Continued on front page F term (reference) 5B047 AA01 AB04 BA02 BB02 BC02 BC05 BC09 BC11 5C051 AA01 BA03 DA03 DB01 DB04 DB22 DB24 DB28 DB34 DB35 DC02 DC04 DC07 DE22 FA01 5C072 AA01 BA12 CA02 DA02 DA04 DA21 EA05 RA12 XA01

Claims (4)

[Claims] 1. A CCD (charge coupled device)
A CCD unit including a reading substrate formed by soldering a line sensor on a printed circuit board, a reading substrate on one surface, and a holding member for holding a CCD line sensor on the back surface, and an imaging lens facing the CCD line sensor. And a reading unit that adjusts the optical axis of the imaging lens to the reading line of the CCD line sensor by displacing the CCD unit and the imaging lens relatively. In the image reading apparatus, a holding member of the CCD unit is provided between the CCD line sensor fixed by fixing means and the reading substrate, and the CCD line sensor is pressed and held by the holding member. Image reading device. 2. The CCD line sensor according to claim 1, wherein the holding member has one surface to which a surface to be read of the CCD line sensor abuts and the other surface fixed to the reading substrate. 2. The image reading apparatus according to claim 1, wherein an elastic member is provided on one surface of the holding member to fix and hold the image reading device. 3. The CCD unit, wherein the elastic members are provided at both ends in the axial direction of the CCD line sensor, and at least one end side of the CCD line sensor is positioned relative to a positioning member protruding from one surface of the holding member. 3. The image reading apparatus according to claim 2, wherein position control is performed by urging a line sensor in a direction of the holding member and in an axial direction and a width direction of the CCD line sensor. 4. The CCD unit according to claim 1, further comprising, on an adhesive surface between the holding member and the reading substrate, an application for avoiding a lead connecting the CCD line sensor and the reading substrate.
The image reading apparatus according to claim 3, wherein an opening is provided as a heat radiation space of the D unit.