JPH10243170A - Image reader - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent dirt on an inner face of a glass plate of an original platen by providing a means cleaning the inner face of the glass plate. SOLUTION: An optical image on an original face obtained by the scanning of an exposure light source unit 8 in the image reader is formed on a solid-state image pickup element such as an image sensor 3 aligned with an optical axis via an image pickup lens. A cleaner brush 9 is placed to the exposure light source unit (lighting unit) 8 and the brush 9 is used to clean an inner face of a glass plate in the case of scanning the exposure light source unit (lighting unit) 8. A fan is used in the reader to cool the original platen glass plate with air flowing from an air suction to an exhaust port and also to remove dust and condensation of the inner face. Thus, the position of the image sensor 3 is maintained with high precision and an advantageous design in terms of the luminous quantity is attained.

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, and more particularly, to a reading optical system used for a copying machine, a facsimile, and the like.

[0002]

2. Description of the Related Art Japanese Unexamined Patent Publication No. 1-194567 (image reading apparatus) discloses that, out of a machine frame side plate of a document reading device, a ventilation means is provided on one side plate and the other side plate facing the side plate is provided on the other side plate. It has been proposed to provide an opening and form a flow of air inside the device to lower the temperature inside the device.

[0003]

However, Japanese Patent Application Laid-Open Publication No.
In the conventional image reading apparatus described in JP-A-194567, since outside air is taken into the image reading apparatus, moisture and dust outside the apparatus are taken in at the same time to stain the inner surface of the platen glass and the mirror. There were drawbacks.

According to the present invention, there is provided an image reading apparatus having an outside air intake opening and an exhaust means as described above, which is provided with a means for cleaning the inner surface of a glass platen of a document table, thereby solving the above-mentioned disadvantages of the prior art. .

[0005]

According to a first aspect of the present invention, an original on a platen glass is scanned and exposed by an exposure light source, a light beam exposed on the original is formed into an image in an image pickup unit, and the outside air is sucked. In an image reading apparatus having an opening for air and an exhaust means, a scanning body for scanning the exposure light source unit is provided with means for cleaning the inner surface of the glass of the platen,
Thus, the inner surface of the glass of the platen is cleaned.

According to the first aspect of the present invention, the inner surface of the platen glass and the cleaner brush are charged by friction or the like.
There is a problem in that charged dust and originals on the outer surface of the platen glass are stuck to the inner surface of the glass. According to a second aspect of the present invention, in the image reading apparatus according to the first aspect, the cleaning means is made of a conductive material, and a casing of the image reading apparatus and the cleaning means are engaged so as to have the same potential. Characterized in that
Thus, the problem of charging as described above has been solved.

According to the second aspect of the present invention, there is a problem that the air cooling effect is not improved because the outside air sucked by the cleaner brush is still hard to flow. According to a third aspect of the present invention, in the image reading device according to the first or second aspect,
The cleaning means and a wing-shaped receiving surface oriented in a direction substantially perpendicular to each other are provided on a receiving shaft, the receiving shaft is rotatable about the shaft, and the cleaning means is provided on a holding member provided on the exposure light source unit. It is engaged by an elastic member, the exposure light source unit is scanned near both ends of the scanning range in the sub-scanning direction,
When the wing-shaped receiving surface hits a pin provided inside the image reading apparatus, the cleaning unit is rotated about the receiving shaft, and the cleaning unit comes into contact with or separates from the inner glass surface of the document table. The present invention is characterized in that the above-mentioned problem of the air cooling effect is solved.

In the first and second aspects of the present invention, there is still a problem that the cleaning effect is reduced if the cleaner brush is soiled. According to a fourth aspect of the present invention, in the image reading apparatus according to any one of the first to third aspects, the cleaning unit engaged with the illumination unit is provided near the end of a scanning range in the sub-scanning direction. A comb-shaped projection is provided in the image reading apparatus so that the crossing is performed, thereby solving the problem of the cleaning effect as described above.

In the invention of claim 4, there is still a problem in that dust generated when the cleaner brush is cleaned adheres to the inner surface of the glass again. The invention of claim 5 is the invention of claim 4
Wherein the illumination unit is scanned in the sub-scanning direction, and a container having an opening is provided near a position where the protrusion and the cleaning unit intersect near an end of a scanning range. The present invention has solved the problem of dust adhering to the inner surface of glass as described above.

In the invention of claim 5, there is still a problem in that dust that has been cleaned from the cleaner brush and leaked from the container adheres to the inner surface of the glass again. According to a sixth aspect of the present invention, in the image reading apparatus according to the fourth or fifth aspect, there is provided means for distributing the sucked air to the inner surface of the platen glass to cover an upper portion of the intersection of the cleaning means and the protrusion. Thus, the problem of leakage of garbage from the container as described above is solved.

[0011] The invention of claim 5 has a problem in that dust falling in the container still floats due to vibration or the like and adheres again to the inner surface of the glass. According to a seventh aspect of the present invention, there is provided the image reading apparatus according to the fifth or sixth aspect, wherein a detachable sheet having a viscous member attached to a surface thereof is disposed in the container. This solves the problem of redeposition.

According to the fifth aspect of the present invention, there is a problem in that when the dust in the container is full, the overflowed dust adheres to the inner surface of the glass again. The invention of claim 8 is
The image reading apparatus according to claim 5, further comprising a discharge port having a mechanism that can be opened and closed so as to discharge dust in the container. Is a solution to the overflow problem.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a schematic diagram showing a main part of an image reading apparatus to which the present invention is applied, wherein 1 is a platen glass, 2 is an exposure light source, and 3 is an exposure light source. An image sensor, 4 is an imaging unit, 5 is a cooling fan, 6 is a suction port, 7 is an exhaust port, 8 is a lighting unit (exposure light source), and in a conventional image reading apparatus, as shown in FIG. A light image of the document surface obtained by the exposure scanning is formed on a solid-state imaging device such as an image sensor provided around an optical axis via an imaging lens.

More specifically, the temperature of the platen glass 1 on which the original is placed is raised by the exposure light source 2 which irradiates the original (not shown). If the image reading apparatus is continuously operated for a long time, the temperature of the platen glass 1 rises, and the placed document may stick to the platen glass 1. The heat source for raising the ambient temperature in the image reading device is, in addition to the light source 2, an image sensor 3 (CC).
D and the like, a drive circuit of the image sensor, an AD conversion circuit, a drive motor in the apparatus, and conduction heat and radiant heat from outside the apparatus. In particular, the position accuracy of the imaging unit 4 is slightly changed due to a change in the surroundings, so that the image output becomes inaccurate. Conventionally, in order to maintain and stabilize high accuracy, the temperature of the solid-state imaging device 3 and the radiant heat and heat conduction from the light source 2 and other heat sources are reduced to detect an increase in the ambient temperature in the apparatus. The cooling fan 5 is operated to draw in outside air from a suction port 6 in the side plate to cool it, and to exhaust the raised air in the apparatus from an exhaust port 7 in the side plate at the opposite position. .

However, when moisture enters through the opening and dew condensation occurs on the inner surface of the platen glass surface 1,
Turbulent airflow inside the apparatus due to the intake of outside air may enter the inside of the apparatus or from a gap in the apparatus, or may attach fine dust passing through the filter unit. FIG. 2 is a schematic diagram of a main part for explaining an embodiment of the first aspect of the present invention. As shown in FIG. 2, an exposure light source unit (illumination unit) 8 is provided with a cleaning means (cleaner brush) 9. . Therefore, not only the conventional effect of cooling the platen glass 1, but also the dew condensation and dust on the inner surface can be removed, the position of the image sensor 3 can be maintained with high accuracy, and a design advantageous in terms of light quantity can be made.

(Invention of Claim 2) FIG. 3 is a view for explaining an embodiment of the invention of Claim 2, in which a conductive member 10 is engaged with a cleaner brush 9 as shown in FIG. As a result, the platen glass surface 1 and the cleaner brush 9 can be prevented from being charged, and the charged dust floating in the apparatus can be prevented from adhering. Further, it is possible to prevent the original placed on the platen glass surface from sticking and dust.

(Invention of Claim 3) FIG. 4 is a view for explaining an embodiment of the invention of claim 3, wherein the lighting unit 8 is provided with a cleaning means 11 as shown in FIG. As shown in FIG. 5, the means 11 has a cleaner brush 9, a blade-shaped receiving surface 12 and a blade-shaped receiving surface 13 integrally formed, and is rotatable by a receiving shaft 16. It is configured to be engaged with the extended holding member 15 by the engagement spring 14.

FIG. 6 is a diagram for explaining the operation of the third aspect of the present invention. First, as shown in FIG. 6A, when the illumination unit 8 is scanning in one direction, the cleaner brush is used. 9 cleans the platen glass surface 1. As shown in FIG. 6B, when the lighting unit 8 approaches the pin 17, the cleaning unit 1
6, the cleaner brush 9 rotates around the receiving shaft 16, and the cleaner brush 9 faces downward as shown in FIG. Move away from Even if the illumination unit 8 scans in the opposite direction, since the engagement brush 14 is engaged, the cleaner brush 9 is scanned by the illumination unit 8 facing downward, and during that time, the platen glass surface 1 is air-cooled. (See FIG. 6D). Further, when the illumination unit 8 is scanned and reaches the end of the scanning range, as shown in FIG.
The pin 18 hits the wing-shaped receiving surface 12, and the cleaner brush 9 rotates about the receiving shaft 16, and hits the original table glass surface 1 again. When the illumination unit 8 starts scanning in the original direction, the original table glass surface 1 is cleaned again. As a result, it is possible to perform cleaning with an air cooling effect as compared with the case of the first aspect.

(Invention of Claim 4) FIG. 7 is a view for explaining an embodiment of the invention of claim 4, wherein a brush 19 for cleaning the cleaner brush 9 is provided at one end as shown. As shown in FIG. 7B, when the cleaner brush 9 reaches the end of the scanning unit and rotates about the receiving shaft 16, the cleaner brush 9 adheres to or is caught by the brush 19. Garbage is cleaned. By repeating this operation, the cleaning effect of the cleaner brush 9 can be maintained for a long time.

(Invention of Claim 5) FIG. 8 is a view for explaining an embodiment of the invention of claim 5, in which a container 20 is provided as shown in FIG. The possibility that the refuse cleaned by the brush 19 by being stored in the brush 20 is stirred again by the inhaled air is reduced, and the inside of the apparatus can be stably cleaned.

(Invention of Claim 6) FIG. 9 is a view for explaining an embodiment of the invention of claim 6, wherein a cover 21 is provided on the upper part of a container 20 as shown. In this way, the air sucked from the opening 6 rises along the cover 21 and is guided to the platen glass surface 1 and avoids the container 20, so that the dust collected by the brush 19 is less likely to be stirred, The air cooling effect is also improved.

(Invention of Claim 7) FIG. 10 is a view for explaining an embodiment of the invention of claim 7, and in this invention, a viscous member 24 is provided on a container 20.
It is possible to prevent dust accumulated in 0 from flying up due to turbulence or the like in the apparatus, thereby increasing the cleaning effect and maintaining high-precision performance.

(Invention of Claim 8) FIG. 11 is a view for explaining an embodiment of the invention of claim 8, wherein an opening 22 having a lid 23 is provided on the apparatus main body so that the container 20 can be taken out. It is provided. Thus, even if the container 20 is full of dust, the container 20 can be replaced with an empty container 20, and the cleaning effect can be maintained for a long time.

[0024]

According to the first aspect of the present invention, an original on a platen glass is scanned and exposed by an exposure light source to form an image of a light beam exposed on the original in an image pickup unit. In the image reading apparatus having the air discharging means, since the scanning body for scanning the exposure light source and the like is provided with the means for cleaning the inner surface of the glass of the platen, the inner surface of the glass of the platen can be cleaned.

According to a second aspect of the present invention, in the image reading apparatus of the first aspect, the cleaning means is made of a conductive material,
The housing of the image reading device and the cleaning means are engaged so as to have the same potential, so that the inner surface of the platen glass and the cleaning brush may be charged by friction or the like, so that the inner surface of the glass may be charged. And the problem that a document on the outer surface of the platen glass is stuck.

According to a third aspect of the present invention, in the image reading apparatus according to the first or second aspect, the cleaning means and a wing-shaped receiving surface oriented substantially perpendicular to each other are provided on a receiving shaft, and the receiving shaft is provided. Is rotatable about an axis, the cleaning unit is engaged with a holding member provided on the illumination unit by an elastic member, and the illumination unit is scanned near both ends of a scanning range in the sub-scanning direction, and the image is scanned. A mechanism in which the cleaning means is rotated about the receiving shaft when the wing-shaped receiving surface hits a pin provided inside the reading device, and the cleaning means contacts or separates from the inner surface of the glass of the platen; Therefore, it is possible to solve the problem that the outside air sucked by the cleaner brush becomes difficult to flow and the air cooling effect does not increase.

According to a fourth aspect of the present invention, in the image reading apparatus according to any one of the first to third aspects, the cleaning means engaged with the illumination unit is provided near an end of a scanning range in the sub-scanning direction. A comb-shaped protrusion is provided in the image reading device so that the cleaning means intersects with each other, thereby solving the problem that the cleaning brush is soiled and the cleaning effect is reduced.

According to a fifth aspect of the present invention, in the image reading apparatus according to the fourth aspect, the illumination unit scans in the sub-scanning direction, and the projection and the cleaning unit intersect near an end of a scanning range. Is provided with a container having an opening in the vicinity of the above, so that the problem that dust when the cleaner brush is cleaned adheres to the inner surface of the glass again can be solved.

According to a sixth aspect of the present invention, in the image reading apparatus according to the fourth or fifth aspect, means for distributing the sucked air to the inner surface of the platen glass to cover an upper portion of the intersection of the cleaning means and the projection. This solves the problem that dust that has leaked from the container due to dust that has cleaned the cleaner brush adheres to the inner surface of the glass again.

According to a seventh aspect of the present invention, in the image reading apparatus according to the fifth or sixth aspect, a detachable sheet having a viscous member attached to a surface thereof is disposed in the container. It is possible to solve the problem that dust falling inside floats due to vibration or the like and adheres again to the inner surface of the glass.

According to an eighth aspect of the present invention, in the image reading apparatus according to any one of the fifth to seventh aspects, a discharge port having an openable and closable mechanism is provided to discharge dust in the container. Therefore, it is possible to solve the problem that the dust in the container becomes full and the dust overflows and adheres again to the inner surface of the glass.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of a main part for explaining an example of an image reading apparatus to which the present invention is applied.

FIG. 2 is a main part configuration diagram for explaining an embodiment of the invention of claim 1;

FIG. 3 is a diagram for explaining an embodiment of the invention of claim 2;

FIG. 4 is a diagram for explaining an embodiment of the invention of claim 3;

FIG. 5 is a diagram showing details of a cleaning unit 11;

FIG. 6 is a diagram for explaining the operation of the invention of claim 3;

FIG. 7 is a view for explaining an embodiment of the invention of claim 4;

FIG. 8 is a diagram for explaining an embodiment of the invention of claim 5;

FIG. 9 is a diagram for explaining an embodiment of the invention according to claim 6;

FIG. 10 is a diagram for explaining an embodiment of the invention of claim 7;

FIG. 11 is a diagram for explaining an embodiment of the invention of claim 8;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Platen glass 2 ... Exposure light source 3 ... Image sensor 4 ... Imaging unit 5 ... Cooling fan 6 ... Suction port
7 ... exhaust port, 8 ... lighting unit, 9 ... cleaner brush, 10 ... conductive member, 11 ... cleaning means, 12, 13 ...
Blade-shaped receiving surface, 14: engagement spring, 15: holding member, 16
... Receiving shaft, 17, 18 ... Pin, 19 ... Brush, 20 ... Container, 21 ... Cover, 22 ... Opening, 23 ... Lid, 24 ... Viscous member.

Claims (8)

[Claims] 1. An image reading apparatus for scanning and exposing a document on a platen glass with an exposure light source to form an image of a light beam exposed on the document in an image pickup unit. In an image reading apparatus having a wind means,
An image reading apparatus comprising: a scanning member that scans an exposure light source unit; 2. The image reading apparatus according to claim 1, wherein
An image reading apparatus, wherein the cleaning means is made of a conductive material, and a housing of the image reading apparatus and the cleaning means are engaged so as to have the same potential. 3. An image reading apparatus according to claim 1, wherein said cleaning means and a wing-shaped receiving surface oriented substantially perpendicular to each other are provided on a receiving shaft, and said receiving shaft is centered on said shaft. The cleaning unit is rotatable, the cleaning unit is engaged with a holding member provided in the exposure light source unit by an elastic member, and the exposure light source unit is scanned near both ends of a scanning range in the sub-scanning direction, and the inside of the image reading device is The cleaning means is rotated about the receiving shaft when the wing-shaped receiving surface comes into contact with a pin provided on the platen, and the cleaning means has a mechanism for coming into contact with or separating from the inner glass surface of the document table. An image reading apparatus characterized by the above. 4. The image reading apparatus according to claim 1, wherein the cleaning unit engaged with the exposure light source unit is located near an end of a scanning range in a sub-scanning direction, and the cleaning unit is provided with the cleaning unit. An image reading device comprising a comb-shaped projection in the image reading device so as to intersect. 5. The image reading apparatus according to claim 4, wherein the exposure light source unit scans in the sub-scanning direction, and an opening is provided near an end of a scanning range near a position where the projection intersects with the cleaning unit. An image reading device comprising a container having a portion. 6. The image reading apparatus according to claim 4, further comprising means for distributing the sucked air to the inner surface of the platen glass to cover an upper portion of the intersection of the cleaning means and the projection. Image reading device. 7. The image reading apparatus according to claim 5, wherein a detachable sheet having a viscous member attached to a surface thereof is disposed in the container. 8. The image reading apparatus according to claim 5, further comprising a discharge port having an openable and closable mechanism for discharging dust in the container.