JPH05308478A - Reader - Google Patents

Abstract

PURPOSE:To provide the reader by which a defect such as choking of originals is prevented to attain smooth feeding of the original when the original is recipro cated for subscanning. CONSTITUTION:The cross section of original guides 21, 22 along the original drive direction is formed to be high in the middle and to have a projection having a slope whose slope angle is 45 deg. or below at both sides, and the height of the original guides 21, 22 in the vicinity of the light transparent plate is formed lower than the height of an original drive face 13a and the height in the middle of the original guides 21, 22 is higher than the height of the original drive face 13a.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a contact type reader used in a facsimile, a card reader or the like.

[0002]

2. Description of the Related Art FIG. 7 is a schematic sectional view showing an example of a conventional reading device. The reading device includes a transparent plate 53 made of glass or acrylic resin, a plurality of light sources 51 in which LEDs (light emitting diodes) and the like are linearly arranged, an imaging optical system 55 such as a rod lens array, and a large number of light sources. It is composed of a light receiving element 56 having a photoelectric conversion element, and a housing 59 for holding the translucent plate 53, the light source 51 and the imaging optical system 55.

Document guides 61 and 6 are provided on both sides of the transparent plate 53.
2 is formed, the document 50 passes over the document guide portion 61, is conveyed at a constant speed in the sub-scanning direction by the rotation of the feed roller 60 while being in contact with the translucent plate 53, and further, the document guide portion 62. Pass over. Along with this operation, the light source 51 fixed to the substrate 52 emits light and illuminates the original 50 obliquely through the transparent plate 53, and the reflected light from the original 50 again passes through the transparent plate 53. The light enters the image forming optical system 55 and a document image is formed. The light receiving element 56 fixed on the bottom plate 58 receives the original image and outputs a read signal corresponding to the original to the circuit board 57. In this way, the image information of the document or the card is read and converted into an electric signal.

[0004]

However, in the conventional reading device, since the sub-scanning of the original 50 is designed on the premise that the original 50 is fed in only one direction, the original 50 is reciprocated back and forth. There is a problem that an accident such as a document jam occurs during bidirectional feeding for scanning.

As shown in FIG. 7, in the area A surrounded by the chain double-dashed line, the height of the original running surface of the light transmitting plate 53 is lower than the height of the original guide section 61, so the original 50 is placed in the original guide section 6.
Even in the case of the forward feed from 1 to the transparent plate 53, the front end of the document 50 is transported without being caught by the end of the transparent plate 53.

On the other hand, also in the area B surrounded by the chain double-dashed line, the original guide portion 62 is formed due to the height of the original traveling surface of the transparent plate 53.
Since the height of the document is low, the front end of the document 50 can pass without being caught even in the forward feeding.

However, in the case where the document 50 is fed from the document guide portion 62 toward the light transmitting plate 53 in the backward direction, the area A is used.
Further, in the area B, a portion having a step is likely to be caught, and a document jam occurs.

As a countermeasure against this, it is conceivable that the height of the original running surface of the transparent plate 53 and the height of the original guides 61 and 62 are formed to be the same (JP-A-3-219759).
Gazette), the thickness error of the transparent plate 53 and the document guide portions 61, 6
If the height of the original running surface of the light transmitting plate 53 becomes higher than the height of the original guide portions 61 and 62 due to the processing error of No. 2, as shown in FIG. At this time, in the area B, the edge of the document 50 is easily caught.

Further, as shown in FIG. 9, the document guide portion 6
When the heights of 1 and 62 are higher than the height of the document traveling surface of the translucent plate 53, the edge of the document 50 is likely to be caught in the region B during the forward feeding and in the region A during the backward feeding. ..

In order to solve the above-mentioned problems, an object of the present invention is to prevent an accident such as a document jam when a document is reciprocally reciprocally scanned in a sub-scan manner and to perform a smooth document feeding. Is to provide.

[0011]

SUMMARY OF THE INVENTION According to the present invention, a light-transmitting plate that holds a document to be conveyed, a light source that illuminates the document, and light reflected from the document are imaged to form a document image. In a reading device including an image optical system, a light receiving element for receiving the original image, and a housing for holding the light transmitting plate, the light source, and the image forming optical system, a document is provided on both sides of the light transmitting plate in the conveying direction. A guide portion is formed, and a cross-sectional shape of at least one of the document guide portions along the document conveyance direction is
The reading device has an inclined portion on the light transmitting plate side, and an inclination angle of the inclined portion is 45 ° or less with respect to a document traveling surface of the light transmitting plate.

[0012]

According to the present invention, the document guide portions are formed on both sides of the light transmitting plate, and the cross-sectional shape of at least one of the document guide portions along the document conveying direction has the inclined portion on the light transmitting plate side. Since the inclined portion has the inclination angle of 45 ° or less with respect to the document traveling surface of the light-transmitting plate, the edge of the document is not caught by the document guide portion and is smooth as described later. The document can be conveyed.

[0013]

1 is a schematic sectional view showing a reading apparatus according to an embodiment of the present invention. The reading device includes a transparent plate 13 made of glass or acrylic resin, a plurality of light sources 11 in which LEDs (light emitting diodes) and the like are linearly arranged, an imaging optical system 15 such as a rod lens array, and a large number of light sources. Light receiving element 16 having a photoelectric conversion element, transparent plate 13, light source 11
And a housing 19 that holds the imaging optical system 15.

Documents such as prepaid cards, telephone cards, shopping cards, documents, and photographs 1
0 is conveyed at a constant speed in the sub-scanning direction by the rotation of the feed roller 20 while being in contact with the transparent plate 13. Along with this operation, the light source 11 fixed to the substrate 12 emits light and illuminates the original 10 obliquely through the transparent plate 13, and the reflected light from the original 10 again passes through the transparent plate 13. ,
It is incident on the imaging optical system 15 and a document image is formed. In addition,
The optical reading surface 14 is affected by the refractive index of the transparent plate 13.
Moves from the actual position on the document surface.

Light receiving element 16 fixed on the bottom plate 18
Receives a document image and outputs a read signal corresponding to the document. The light receiving element 16 is formed by forming a large number of photoelectric conversion elements on a semiconductor substrate such as silicon by a well-known photolithography technique or ion beam processing method, and is formed on a circuit board 17 made of glass epoxy resin or the like. Wired to the conductor pattern.

The housing 19 made of a metal such as aluminum or a resin such as glass fiber reinforced plastic or glass-filled polycarbonate has a hollow structure for passing the reading light and blocking the external light. In addition to being elongated along the (main scanning direction),
The light source 11 and the substrate 12 are held on the inclined surface 23 of the inner surface of the housing 19.

FIG. 2 is a schematic configuration diagram showing a document feeding mechanism of a facsimile using the reading device according to the present invention.

From the opening of the facsimile body 30, the original 1
When 0 is inserted, an optical sensor including an LED (light emitting diode) 31a and a PT (phototransistor) 31b detects the original 10 and the transport rollers 32a, 32b, 3 are detected.
4a and 34b are rotated, and the conveyance guide 3 is provided until the optical sensor including the LED 35a and the PT 35b detects the original 10.
The document 10 is fed along the lines 3a and 33b.

When the leading edge of the original 10 reaches the feed roller 20 and the trailing edge of the original passes the optical sensor composed of the LEDs 35a and PT 35b, the feed roller 20 rotates and the reading device 1 biased by the spring 36 is released. Reading is started while closely contacting the original 10.

When the optical sensor composed of the LED 38a and the PT 38b detects the original 10, the conveying rollers 39a, 39 are fed.
b, 41a, 41b rotate, LED42a and PT42
The conveyance guide 40 until it passes the optical sensor composed of
The document 10 is fed along the a, 40b, and 43.

On the contrary, when the document 10 is conveyed in the opposite direction to the above, the rotation direction of the feed roller 20 is reversed and the control order of the front and rear optical sensors and the respective conveyance rollers is reversed.

In the above structure, a contact sensor such as a micro switch may be used instead of the non-contact sensor such as an optical sensor.

Next, the document guide portions 21 and 22 formed on both sides of the transparent plate 13 will be described.

FIG. 3 is a partial cross-sectional view showing a contact state between the original 10 and the original guide portion 22. Assuming that the friction coefficient between the document 10 and the document guide portion 22 is so small as to be negligible, the inclination angle of the document guide portion is θ, and the vertical reaction force that the document 10 receives from the surface of the document guide portion 22 is N, The component force M for returning the manuscript 10 can be represented by N cos θ, and the manuscript 1
The component force L that pushes 0 upward can be expressed by Nsin θ. If the tilt angle θ is less than 90 °, L = Nsin θ> 0
Therefore, the original 10 can be pushed upward, but at that time, the component force M for returning the original 10 is close to the magnitude of the vertical reaction force N, so that the original 10 buckles and the original jams. Will occur.

Therefore, the condition that at least the component force L is equal to or more than the component force M, that is, Nsin θ ≧ Nc
In order to satisfy osθ, the inclination angle θ needs to be 45 ° or less. If the friction coefficient between the document 10 and the document guide portion 22 is too large to be ignored, it is preferable that the inclination angle θ be smaller than 45 °.

As shown in the partial sectional view of FIG. 4, the document guides 21 and 22 are formed in a convex shape having a high central portion and inclined portions on both sides thereof along the document traveling direction. ..

In the areas A and B surrounded by the two-dot chain line,
The height of the document guide portion near the light-transmitting plate is formed lower than the height of the document traveling surface 13a of the light-transmissive plate 13, while the height of the central portion of the document guide portions 21 and 22 is equal to the height of the document traveling portion. Even when using the translucent plate 13 which is formed higher than the height of the surface 13a and has a variation in thickness for each sheet, each height is determined so as to satisfy these conditions. The height difference between the highest portion of the document guide portion and the document traveling surface 13a is preferably about 2 mm or less.

The original 10 is transferred from the original guide 21 to the light-transmitting plate 13.
In the case of the forward feeding in which the document 10 is fed to the document, the document 10 enters the document guide portion 21 in a substantially horizontal state, and the portion beyond the contact point in the central portion draws a bending curve determined by the weight and rigidity of the document 10. .. Therefore, the difference in height between the vicinity of the transparent plate of the document guide portion and the document traveling surface 13a is determined so that the front end of the document 10 does not contact the end surface of the transparent plate 13 even when the document 10 is bent. ..

The front end portion of the original 10 which has passed through the area A enters the area B by being fed in the forward direction. In the region B, the vicinity of the light guide plate of the document guide portion 22 is formed lower than the document traveling surface 13a as in the case described above, so that the front end of the document 10 can smoothly pass through the region B. Further, since the inclined portion of the document guide portion 22 on the light-transmitting plate side is formed at an angle of 45 ° or less with respect to the document traveling surface 13a, the front end of the document 10 can be smoothly moved without being caught. You can

On the other hand, also in the case where the original 10 is conveyed from the original guide 22 toward the translucent plate 13 in the reverse direction, the original 10 enters the original guide 22 in a substantially horizontal state, and the original 10 is placed at the center. The portion beyond the contact point draws a bending curve which is determined by the weight and rigidity of the original document 10, and the front end portion of the original document 10 (in the case of reverse feeding, it is opposite to the front end portion of forward feeding).
However, the height difference between the vicinity of the transparent plate of the document guide portion 22 and the document traveling surface 13a is determined so as not to contact the end surface of the transparent plate 12.

When subsequently conveyed in the opposite direction and approaching the area A, the inclined portion of the document guide portion 21 on the light transmitting plate side is at an angle of 45 ° or less with respect to the document traveling surface 13a, as described above. Since it is formed, the front end of the document 10 can be smoothly moved without being caught.

FIG. 5 is a partial sectional view of a reading device according to another embodiment of the present invention. As compared with the reading apparatus shown in FIG. 1, the document guide portions 21 and 22 are different in that a cross-sectional shape has a flat portion at the center. Even with such a configuration, similar to the above, smooth document feeding can be performed by either forward feeding or backward feeding of the original.

FIG. 6 is a partial sectional view of a reading device according to another embodiment of the present invention. The difference from the reading device of FIG. 1 is that the document guide portions 21 and 22 are formed in an arc shape having a predetermined curvature. Even with this configuration,
Similar to the above, smooth document feeding can be performed by either forward feeding or backward feeding of the original.

In each of the above embodiments, an example in which the document guide portions 21 and 22 are formed to have the same cross-sectional shape has been described. For example, the document guide portion 21 in FIG. 1 and FIG.
The cross-sectional shape of each document guide unit may be appropriately selected, such as a combination with the inside document guide unit 22. If the original is fed only in the forward direction, for example, in area A in FIG. 4, the height of the original guide portion 21 in the vicinity of the light-transmitting plate may be higher than the original traveling surface 13a. The inclined portion of the document guide portion 21 on the side of the transparent plate in the area A may not be formed.

Further, in each of the above-mentioned embodiments, the example in which the respective document guide portions 21 and 22 are formed integrally with the housing 19 has been described, but a member different from the housing 19 is processed into a predetermined cross-sectional shape. The original guides 21 and 22 are used as the housing 19
You can fix it to.

[0036]

As described above in detail, according to the present invention,
When the document travels in the predetermined direction on the traveling surface of the translucent plate, it is possible to prevent the edge of the document from being caught or jammed, so that the document can be smoothly transported. In particular, smooth document transportation can be performed even in the case of bidirectional feeding in which a document is reciprocally reciprocally scanned.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view showing a reading device according to an embodiment of the present invention.

FIG. 2 is a schematic configuration diagram showing a document conveying mechanism of a facsimile using the reading device according to the present invention.

FIG. 3 is a partial cross-sectional view showing a contact state between a document 50 and a document guide portion 62.

FIG. 4 is a partial cross-sectional view showing a reading device according to an embodiment of the present invention.

FIG. 5 is a partial cross-sectional view of a reading device according to another embodiment of the present invention.

FIG. 6 is a partial cross-sectional view of a reading device according to another embodiment of the present invention.

FIG. 7 is a schematic sectional view showing an example of a conventional reading device.

FIG. 8 is a partial cross-sectional view showing another example of a conventional reading device.

FIG. 9 is a partial cross-sectional view showing another example of a conventional reading device.

[Explanation of symbols]

 Reference numeral 10 originals 11 light source 12 substrate 13 translucent plate 14 reading surface 15 imaging optical system 16 light receiving element 17 circuit board 18 bottom plate 19 housing 20 feed rollers 21 and 22 original guide section

Claims (1)

[Claims] 1. A light-transmitting plate for holding a document to be conveyed, a light source for illuminating the document, an image forming optical system for forming reflected light from the document to form a document image, the document image In a reading device including a light receiving element for receiving a light, and a housing for holding the light transmitting plate, the light source, and the image forming optical system, document guide portions are formed on both sides of the light transmitting plate in a conveyance direction, The cross-sectional shape of at least one of the document guide portions along the document transport direction has an inclined portion on the light transmitting plate side, and the inclination angle of the inclined portion is the original traveling surface of the light transmitting plate. A reading device characterized in that the angle is 45 ° or less with respect to.