JPH067622Y2 - Image reader - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image reading device used in a copying machine, a facsimile, or the like to read an image recorded on a sheet.

2. Description of the Related Art An image reading apparatus normally illuminates a sheet on which an image is recorded and reads the image based on the amount of light reflected from the sheet. One of them is (a) an image reading head that includes a light emitting unit that emits light toward a sheet on which an image is printed and a light receiving unit that receives reflected light from the sheet, and reads the image on the sheet set at the reading position. And (b) a first support member that includes a paper support surface that supports the paper from the image reading head side, and that creates a constant gap between the image read head and the paper, and (c) the first support member. It is provided so that it can approach and separate from the other side, contacts the paper from the side opposite to the first supporting member, supports the paper in cooperation with the first supporting member, and has a reference reflectance at a position facing the reading head. Some include a second supporting member having a reference reflecting surface having (1) and (d) a biasing unit that biases the second supporting member toward the first supporting member.

In this image reading device, the light receiving portion emits a signal according to the amount of light received, and the image of the portion of the paper illuminated by the light is read based on the signal, but there is a manufacturing error in the light emitting portion and the light receiving portion. In this case, an error occurs in the signal emitted by the light receiving section, and the image cannot be read accurately. Therefore, the light emission amount of the light emitting unit is adjusted in advance before the image is read so that the image can be read accurately. This adjustment is performed by shining light on the reference reflecting surface when the paper is not set and determining whether or not the signal emitted by the light receiving unit is at a predetermined value. The light emission amount is adjusted so that

Further, conventionally, the reference reflecting surface has been provided at a position retracted from the surface of the second supporting member that contacts the paper. That is, the concave portion is provided on the surface of the second supporting member that contacts the paper, and the bottom surface of the concave portion serves as the reference reflecting surface.

In this way, the paper does not come into contact with the reference reflection surface during image reading, so the reference reflection surface does not get dirty, and the light emitted from the light emitting unit has the reference reflectance. Therefore, the amount of emitted light can be accurately adjusted. However, the reference reflection surface is located farther from the light emitting unit than the paper support surface, and the light emission amount is adjusted with reference to the surface at a position different from the position where the image is actually read. There is a problem that the image reading accuracy is reduced.

Means for Solving the Problems In order to solve the above problems, the present invention provides (a) an image reading head, (b) a first supporting member, (c) a second supporting member, (d).
In an image reading apparatus having a biasing means, the second support member is brought into contact with the second support member when the paper is supported between the second support member and the first support member by contacting the second support member. Is provided at a position where the reference reflection surface does not contact the paper, and the first support member receives the projection when the paper is not supported, and the reference reflection surface has the first support member. A recess is provided to allow the second support member to approach the first support member until the second support member is positioned on the extension surface of the support surface.

Functions and Effects Even in the image reading apparatus configured as described above, the amount of light emitted from the light emitting section is adjusted in the same manner as before, when no paper is set.In this state, the projection is received in the recess. Thus, the reference reflection surface is positioned on the extension surface of the paper support surface. Since the reference reflection surface is located exactly at the same position as the image recording surface of the paper, the amount of light emission can be adjusted in the same state as when actually reading the image, making it suitable for reading the image. The amount of light emission can be adjusted to a large size, and the reading accuracy can be improved.

In addition, when the image is read, the reference reflection surface is kept in a position where it does not come into contact with the paper due to the projections coming into contact with the paper, so it does not get dirty and does not interfere with the adjustment of the light emission amount, and the effect of improving the reading accuracy is sufficient. Can be enjoyed.

Embodiment Hereinafter, an embodiment embodying the present invention will be described in detail with reference to the drawings.

FIG. 1 is a diagram showing a main part of the image recording apparatus. In the figure, 10 is an image reading unit for reading an image,
On both sides of the image reading unit 10, an introducing unit 14 that feeds the paper 12 in the horizontal direction and introduces the paper 12 into the image reading unit 10 and a discharge unit 16 that discharges the paper 12 from the image reading unit 10 are provided. The introduction portion 14 includes a small diameter roller 18 and a large diameter roller 20 each having a surface made of rubber, and a pair of guide plates 22 and 24 provided on both sides of the rollers 18 and 20 at regular intervals in the vertical direction. Is equipped with. The small-diameter roller 18 is biased by a leaf spring (not shown) in such a direction as to approach the large-diameter roller 20, and the large-diameter roller 2 is sandwiched between the rollers 18 and 20.
When the 0 is rotated, the paper 12 is fed. Similarly, the discharge unit 16 includes a small diameter roller 26, a large diameter roller 28, and a pair of guide plates 30 and 32.

The image reading unit 10 is provided with an image reading head 40. The image reading head 40 is long in the direction orthogonal to the paper feeding direction so that the image recorded on the paper 12 can be read as the paper 12 is fed. A light source 42 is provided in the reading head 40 and constitutes a light emitting section together with the light emitting side fiber 44. The light emitting side fiber 44 is connected to the light source 42 at one end thereof,
The other end is exposed on the upper surface 46 of the reading head 40, and the light emitted from the light source 42 is transmitted by the light emitting side fiber 44 and applied to the paper 12.

A photoelectric conversion element 48 is also provided in the reading head 40, and constitutes a light receiving section together with the light receiving side fiber 50. The light receiving side fiber 50 has a photoelectric conversion element 4 at one end thereof.
8, the other end is exposed on the upper surface of the read head 40. The light emitted from the light emitting unit and reflected by the paper 12 is received by the light receiving side fiber 50, transmitted to the photoelectric conversion element 48, converted into an electric signal in the photoelectric conversion element 48, and then determined by a predetermined reference in the determination circuit. Paper 1
It is determined whether or not an image is recorded in 2. In addition,
A large number of the light emitting side fibers 44 and the light receiving side fibers 50 are respectively arranged, and their exposed end faces to the upper surface 46 are aligned along the longitudinal direction of the read head 40.
It is fixed by ABS resin.

L-shaped spacers 52 and 54 are fixed to both edges of the upper portion of the reading head 40 on the side orthogonal to the paper feeding direction. Although it is necessary that there is a certain gap between the upper surface 46 of the reading head 40 and the paper 12, the spacers 52 and 54 have a thickness necessary to form the gap, and The paper 12 is supported on the upper surfaces 56 and 58 at a constant distance from the reading head 40. The spacers 52 and 54 form the first supporting member, and the upper surfaces 56 and 58 form the paper supporting surface.

The spacers 52 and 54 are fixed so as not to cover the exposed portions of the light emitting side fiber 44 and the light receiving side fiber 50 of the reading head 40. The spacers 52 and 54 are orthogonal to the paper feeding direction by the reading head 40 and the spacers 52 and 54. And a recess 60 that is open upward is formed. Further, the corner portion of the spacer 52 on the upstream side has the upper surface 5 on the upstream side.
6 is bent in a direction inclining away from 6,
The guide portion 62 guides the entry of the second vehicle. On the other hand, the upstream end of the downstream spacer 54 is bent into a recess 64 provided in the reading head 40 and serves as a guide portion 65 for guiding the feeding of the paper 12.

A paper pressing member 66 as a second supporting member is arranged above the spacers 52 and 54. The paper pressing member 66 includes the spacers 52,
54 is supported so as to be able to approach / separate from the spacer 54 and to be able to sit on the spacers 52, 54 without the paper 12, and the spacer 52 is provided by a spring 70 as an urging means arranged in the groove 68. , 54 is urged in the direction of approaching. As shown in FIG. 2, the paper pressing member 66 has a long block shape in the direction orthogonal to the paper feeding direction, and the upstream and downstream edges of its lower end are cut away to form an inclined surface 72. , 74 are formed.

The light emitting side fiber 4 on the lower surface of the paper pressing member 66.
4. A white reference reflecting surface 76 having a reference reflectance is provided in a portion facing the light receiving side fiber 50.
Further, it is upstream of the reference reflecting surface 76 on the lower surface of the sheet pressing member 66 in the sheet feeding direction, and the spacer 5
2, 54, the concave portion 6 formed by the read head 40
In the portion corresponding to 0, one protrusion 78 protruding toward the read head 40 side is provided. The protrusion 78 is formed in such a size that the sheet pressing member 66 can be received in the recess 60 while the sheet pressing member 66 is seated on the spacers 52 and 54. Further, the side surface of the protrusion 78 on the upstream side in the paper feeding direction is
The lower side is an inclined surface 80 that is inclined toward the downstream side.

In the image reading apparatus configured as described above, the light emission amount of the light emitting unit is adjusted before reading. This adjustment is performed by shining light on the reference reflecting surface 76 when the paper 12 is not set.
When there is no sheet, the protrusion 78 is received in the recess 60, and the sheet pressing member 66 is seated on the spacers 52 and 54.
Since the reference reflection surface 76 is located on the extension surface of the upper surfaces 56 and 58 that are the paper support surfaces, the light emission amount can be adjusted in the same state as when reading the image recorded on the paper 12, and the image reading can be performed. Will be done accurately.

After the light emission amount of the light emitting unit is set to an appropriate value in this way, reading is performed. The sheet 12 is fed by the guide plates 22, 24 and the rollers 18, 20 and enters between the sheet pressing member 66 and the spacer 52 while lifting the sheet pressing member 66 against the urging force of the spring 70. At this time, the sheet 12 is guided by the guide portion 62 of the spacer 52 and the sheet feeding member 66.
It is possible to easily enter between the spacer 52 and the paper feeding member 66 by being guided by the inclined surface 72 of the.

When the sheet 12 reaches the protrusion 78, the sheet 12 is guided by the inclined surface 80 to enter the lower side of the protrusion 78, pushes up the sheet pressing member 66, and is further moved to the downstream side to be guided by the guide portion 65 and the spacer 54 and the sheet. Enter between the pressing member 66,
The downstream end of the paper pressing member 66 is pushed up. As a result, the sheet 12 is pressed against the spacers 52, 54 by the urging force of the spring 70 via the sheet pressing member 66, and is supported at a constant distance from the upper surface of the reading head 40. Located in. In this state, as shown in FIG. 3, the sheet pressing member 66 keeps the reference reflecting surface 76 away from the sheet 12 with the projection 78 contacting the upper surface of the sheet 12.

In this way, the image reading is started with the sheet 12 set at the reading position. The front end portion of the paper 12 in the feeding direction has the paper pressing member 6 when the paper 12 is set.
Reading is not performed due to being sandwiched between 6 and the spacer 54, but this portion is small and there is no problem in recording an image on the paper 12. And paper 1
2 is intermittently fed at a constant pitch and an image is read, and the portion of the paper 12 that has been read is sent by the guide plates 30, 32 and the rollers 26, 28 and the paper pressing member 66 and the spacers 52, 54. Is discharged from between. When the sheet 12 is set at the reading position as described above, the sheet pressing member 66 is seated on the sheet 12 at the lower end portion side of the downstream side thereof. Since the part is cut out, the paper 12
It does not bite into and prevent its discharge.

Further, since the projection 78 contacts the upper surface of the paper 12, the reference reflection surface 76 is separated from the paper 12,
When the paper 12 is fed, it does not come into contact with and become dirty, and the amount of light emission can be adjusted accurately.

In the above embodiment, the protrusion 78 is the reference reflection surface 7.
Although it is provided only on the upstream side of 6, it may be provided on the downstream side. Further, when a sheet is set in a state where the sheet pressing member 66 is largely separated from the reading head 40, the protrusion may be provided only on the downstream side of the reference reflection surface.

Further, the read head 40, the spacers 52, 54 are formed in the recess 6
Although 0 is formed, a recess may be formed in the spacer 52, or a protrusion that protrudes toward the sheet pressing member 66 side may be integrally provided on the reading head 40 to serve as the first support member.

Furthermore, the present invention can be implemented with various modifications and improvements made to the reading head, the biasing means, etc. based on the knowledge of those skilled in the art.

[Brief description of drawings]

FIG. 1 is a front sectional view showing a main part of an image reading apparatus according to an embodiment of the present invention. FIG. 2 is a perspective view showing a sheet pressing member of the image reading apparatus. FIG. 3 is a front sectional view showing a state in which a sheet is set in the image reading device. 12: paper, 40: image reading head 42: light source, 44: light emitting side fiber 48: photoelectric conversion element, 50: light receiving side fiber 52, 54: spacer, 56, 58: upper surface 60: concave portion, 66: paper holding member 70 : Spring, 76: Reference reflective surface 78: Protrusion

Claims (1)

[Scope of utility model registration request] 1. A light emitting section for emitting light toward a sheet on which an image is printed, and a light receiving section for receiving reflected light from the sheet,
An image reading head that reads an image of a sheet set at a reading position, and a sheet supporting surface that supports the sheet from the side of the image reading head, and a first gap that creates a constant gap between the image reading head and the sheet. The support member and the first support member are provided so that they can approach and separate from each other,
The sheet comes into contact with the sheet from the side opposite to the first supporting member, supports the sheet together with the first supporting member, and has a reference reflecting surface having a reference reflectance at a position facing the reading head. An image reading apparatus comprising: a second supporting member; and a biasing unit that biases the second supporting member toward the first supporting member, wherein the second supporting member includes the second supporting member and the first supporting member. In a state where the sheet is supported between the supporting member and the supporting member, at least one protrusion is provided for keeping the second supporting member in a position where the reference reflecting surface does not contact the sheet by contacting the sheet, and When the paper is not supported by the one support member, the second support member first receives the protrusion until the reference reflection surface is positioned on the extension surface of the paper support surface of the first support member. Approach the support member Image reading apparatus is characterized in that a recess for allowing the.