JPH0657037B2 - Contact image sensor unit - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a contact type sensor unit, and more particularly to a contact type sensor unit that presses a guide plate against a roller to convey and read a document.

[Conventional technology]

Conventionally, as shown in FIG. 5, the guide plate document passage surface is screwed in a direction perpendicular to the original passage surface.
The holder had a receiving surface. The guide plate is made of a SUS (stainless steel) plate material having a plate thickness of 2 mm or more in order to increase the strength.

[Problems that the invention is trying to solve]

In the above-mentioned conventional example, a light source for illumination is provided on a side surface of the portion where the guide plate and the roller are in contact with each other, and the guide plate cannot be pressed from this side surface. Therefore, there is a drawback that the guide plate is easily deformed. If the flatness of the guide plate is not uniform, the document conveying force becomes uneven, which causes light shielding.

In the conventional example, in order to compensate for this drawback, the thickness of the guide plate is increased to increase the strength, and the receiving surface is increased to prevent the deformation. However, in the former case, since the position of the illumination light source is farther from the reading position and the light source is blocked, the light quantity is likely to be insufficient. In the latter case, as shown in FIG.
The unit size increases in the vertical direction in the figure, and eventually
It has a drawback that the entire device becomes large.

[Means for solving problems]

According to the present invention, the guide plate can be thinned by bending the guide plate to the roller side. By bending it into an L-shape, the receiving surface of the guide plate is not required, and the size and weight of the device can be reduced.

〔Example〕

 FIG. 1 is a sectional view showing an embodiment of the present invention.

In particular, the description has been made on a document reading apparatus in which a document is conveyed in a U-turn shape from the lower side to the upper side, and a type using a sensor of the same size for the light receiving element.

In FIG. 1, reference numeral 1 denotes a document, which has image information to be read on the arrow A side. A drive roller 2 conveys the document in the direction of arrow B, and reads the image information of the document 1 while rotating in the direction of arrow C by a drive source (not shown). 3 is a structural frame of the apparatus, 3a and 3b are originals 1 and rollers 2
It is a pair of guides to guide you. 3a is an upper guide, 3
b is the lower guide. Reference numeral 4 is a discharge guide for guiding the original 1 to the outside of the apparatus, 5 is an upper cover of the apparatus, and 5a is a cover which also serves as a guide of the discharge section, which can be rotated in the direction of arrow C and can be repaired when jammed. It has a simple structure. 6 is a bottom cover of the device. Reference numeral 7 denotes a guide plate that applies a conveying force to the original 1 by holding the original 1 between the rollers 2 by a pressing unit, which will be described later, for guiding the original 1.
Reference numeral 8 denotes a reading unit structure to which an illumination unit, a unity-magnification lens unit, a sensor, and the like, which will be described later, are fixed and fixed to the main body.

The structure 8 is made of a material such as an aluminum drawing material, an aluminum die cast material, or a resin. Reference numeral 9 denotes a rotation center hole fixedly provided in the structure (hereinafter referred to as a holder), and the holder 8 is rotatably supported by the main body and the rotation center 9 from both sides. Reference numeral 32 is a pressing means for pressing the reading unit toward the roller 2. Reference numeral 11 is a document reading position, and 12 is a light receiving line on the light receiving element. Reference numeral 13 is an equal-magnification imaging lens for guiding the reflected light at the document reading position to the light receiving position 12. Reference numeral 14 is a light receiving element having a photoelectric light receiving portion at the light receiving position 12.

Reference numeral 20 is an actuator that rotates in synchronization with the insertion of the original 1, 21 is a detector that detects that the actuator has rotated, 3 is a mounting plate that fixes the light receiving element 14, and 31 is a drive substrate that drives the light receiving element 14. Is connected to a system controller (not shown), the light receiving element is driven by an input signal from the system controller, and the optical output signal of the light receiving element 14 is signal processed so as to be transmitted to the system controller and output. Reference numeral 34 is a connector for electrically connecting the light receiving element 14 and the drive circuit 31.

With the configuration described above, in the document reading apparatus of the embodiment, the document 1 is conveyed from the arrow B direction to the B'direction by the roller 2 rotating in the arrow C direction. Manuscript 1
As for the image information on the A side of, the light emitted from the LED chip 10l is condensed and irradiated by the rod lens 10a, and the reflected light is reflected by the lens 13.
Is incident on the light receiving portion of the light receiving element 14 via the
It becomes possible to read the image information which is photoelectrically converted in 4.

FIG. 2 is a perspective view showing more specifically the structure of the unit of the reading section shown in FIG.

Here, the document 1 is inserted from the direction of the arrow B and is made a U-turn in the direction of B'and discharged. The configuration not described in FIG. 1 will be described below. The symbols used are the same as those in FIG.

Reference numeral 2a is a pulley on one side of the roller 2, and 2b is a belt for transmitting a driving force from a driving system (not shown).

Reference numerals 7a and 7b are set screws for fixing the pressing guide 7 to the holder 8, and 8a to 8c are set screws for fixing the lens to the holder 8 from a direction orthogonal to the optical axis of the imaging lens 13, for example, a self-locking lens. The screws 8d to 8e are holes formed in the holder 8 so that the side surface of the lens 13 can be touched from above in FIG. It is possible to adjust the position of the lens 13 in the optical axis direction using the holes by using needle-like projections of a jig (not shown). Reference numerals 8f and 8e are shaft support holes provided on the side surface of the holder 8, 8e is a circular hole, and 8f is an elongated hole. 8
g and 8h are taps provided at both ends of the holder,
This is for fixing the light receiving element mounting plate 30 described in FIG.

9a and 9b are taps provided on the frame 3 from both sides of the device, and the pin portion at the tip thereof is used to hold the holder 8 described above.
Is a stepped screw that fits into the hole, elongated hole, 8f, 8g, and the holder 8 is pivotally supported in the direction of arrow M about this pin as a rotation center.

Reference numeral 10 is an illuminating means as described above. Reference numeral 10e is a minute square light emitting LED chip bonded on the substrate 10b. Reference numeral 10a is a reading position 1 which collects the light emitted from the chip.
A rod-shaped lens for illuminating the original document in 1 and 10d is L
The rod-shaped lens 10a is located on each side of the ED array
A lens house for fixing to the substrate 10b, 10c is L
An external resistor provided for limiting and adjusting the current value of the ED, which is soldered on the LED substrate.

30 is a light receiving element mounting plate, and 30a and 30b are holders 8.
It is a hole through which a fixing screw 33 for fixing is fixed and is larger than the screw diameter and can be fixed by adjusting the position with respect to the mounting plate 30 and the holder 8.

Reference numerals 30c, 30d denote cut-and-raised portions for abutting and positioning the glass end surface of the light receiving element 14, 30e, f,
Similarly, g and h are embossments for abutting the end faces thereof, and 30i and j are fixing surfaces for fixing the drive circuit 31 (hereinafter referred to as PCB), which are provided with taps. 30k, e,
m and n are hooking claws for preventing the PCB from floating (floating), 30 and 30p are spring hooking claws as pressing means, and 31a and b are for fixing the PCB to the mounting plate 30. It is a stop screw.

Here, the operation of the present invention will be described with reference to the drawings.

FIG. 4 is a partial cross-sectional view of the embodiment of the present invention, which is taken from the horizontal axis of the center axis of the roller 2 in FIG.

Here, FIG. 4 (a) shows the time when the guide plate 7 and the roller start to contact each other.

As mentioned above, the CS unit (contact type sensor unit)
Can be released in the direction of arrow D for a jam treatment or the like.
In FIG. 4 (a), the guide plate according to the present invention is used.

That is, the guide plate is curved in a convex shape in the direction of arrow F (direction along the axis of the roller 2), and when the release is stopped, the center of the guide plate first contacts the roller. After that, the pressing springs 32 at both ends are actuated, and the pressing force in the directions of the arrows E and E ′ acts, and the state shown in FIG. 4B is obtained. At this time, the pressing force indicated by the arrow G has a uniform distribution. By the way, FIGS. 6A and 6B show a conventional example using a flat plate guide instead of the conventional convex type. (A) and (b) are different in the length of the roller. However, since the spring 32 is applied to the outside in both cases, the pressing force at the roller central portion tends to be small.

On the other hand, as shown in FIG. 4 (b), L ₁ : width of the guide plate (abutting width on the back side), L ₂ : roller length, L ₃ :
It is assumed to be the length of the spring hook portion. A uniform pressing force can be obtained by appropriately determining the convex amount of the guide plate from the thickness of the guide plate, the gum strength of the rubber roller, and L ₁ , L ₂ , and L ₃ .

〔The invention's effect〕

As described above, a simple structure in which the guide plate is curved in a convex shape on the roller side can provide uniform pressing force, suppress image defects such as skewing, and use thick plates as in the past. The size of the device can be reduced and the price can be reduced because the amount of light can be secured without increasing the size of the device.

[Brief description of drawings]

 FIG. 1 is a sectional view of an embodiment of the present invention, FIG. 2 is a perspective view of the same apparatus, FIG. 3 is a perspective view of a CS unit, FIG. 4 is a sectional view showing a pressed state, and FIG. An example cross-sectional view, FIG. 6 is a cross-sectional view similarly showing a pressed state. 1 is original 2 is roller 7 is guide plate 8 is frame of CS unit 32 is pressing spring

Claims (1)

[Claims] 1. A contact type image sensor unit of a document reading device, which comprises a roller as a document conveying means and sends a document to read image information of the document, and an illuminating means for illuminating the image information surface of the document. Image forming means for forming an image of the reflected light of the document surface by the means, a light receiving element on the image surface of the reflected light for photoelectrically converting the reflected light to read image information, the above-mentioned illumination means, image forming means Positioning the structure that integrally holds the light receiving element and the structure that integrally holds the illumination / imaging / light receiving element described above such that the optical axis of the image forming unit faces substantially the roller. A guide plate which is in contact with the outer periphery of the roller and constitutes a document conveyance path for nipping and conveying the document during conveyance of the document, the guide plate being arranged along the axial direction of the roller. On the roller surface side A close contact type image sensor unit characterized by being bent.