JPH079479Y2 - Image input device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of use] The present invention relates to an image input device for reading an original such as an original or a photograph such as an image scanner or a facsimile.

[Outline of device]

In order to reduce the size, which is the greatest feature of using the contact type image sensor, the present invention has a single conveying roller, and the original guide mechanism of the sensor unit presses the original guide plate of the sensor unit against the conveying roller to feed the original to feed the original. Also, a document detection mechanism consisting of a document sensor that detects the presence or absence of a document and a document cue sensor that replaces the contact type image sensor that detects the cue of a document is provided. A small and inexpensive image input device was obtained.

[Conventional technology]

In a conventional document moving type image input apparatus using a contact type image sensor, two sets of a conveying roller 1 and a facing roller 2 are provided as shown in the sectional view of FIG. The reason for this is that it is necessary to reliably convey the document, because the part to be read and the part to which the document is fed are separated from each other. Reference numerals 3a and 3b denote document detection sensors for detecting whether or not a document is inserted, and are composed of, for example, an infrared photo interrupter. Similarly to the document detection sensor 3, 4a and 4b are also necessary to locate the document. Although not shown in general, a stepping motor is used to rotate the conveying roller 1 by using a gear or a timing belt, and if the leading edge of the document is known by the document cueing sensor 4, after a predetermined number of steps, It is possible to ensure that the leading edge of the original 6 comes on the contact type image sensor 5. 7 is a rod lens array, and 6 is the original.
A real image of 1 × is formed on the contact image sensor 5.
Reference numeral 8 denotes a light source including an LED bar light source, which illuminates the document 6. The contact type image sensor 7, the light source 6, and the rod lens array 7 are attached to a sensor base 9, and a glass plate 10 is provided to avoid dust and to keep the distance between the original 6 and the contact type image sensor 5 accurate. It was Reference numeral 11 is a document guide for guiding the document 6,
They are arranged with a gap of contacting or not contacting the document 6.

[Problems to be solved by the invention]

A conventional document moving type image input device using a contact image sensor has a document detection sensor, a conveyance roller, a document cueing sensor, a sensor unit, and a conveyance roller arranged in this order, and the distance from the insertion of the document to the ejection is extremely long. Therefore, the contact image sensor cannot be downsized while using the contact image sensor, the number of parts is large, and it cannot be provided at a low price. Furthermore, because of the layout, the contact image sensor is under the original,
There was the inconvenience of inserting the manuscript inside out.

An object of the present invention is to solve the above-mentioned conventional problems and to provide an image input device that is small in size, has a small number of parts, is inexpensive, and has good operability.

[Means for solving problems]

In order to solve the problems of the prior art, the present invention provides an original document feeding mechanism in which a single feeding roller is provided, and the original document guide plate attached to the sensor unit is brought into pressure contact with the original document to feed it. A document detection mechanism is constructed by using the output of the contact image sensor for reading the document, and the contact image sensor is arranged above the document.

[Action]

First, when a document is inserted, it is detected by a document detection sensor such as a photo interrupter or a micro switch, and the stepping motor is rotated to rotate the conveying roller. Then, since the document guide is in pressure contact with the transport roller, the document is bite and transported by the frictional force of the transport roller. When the document detection sensor detects, the light source is turned on and the contact image sensor is activated, so that the output of the contact image sensor can be used to find out whether the document comes on the contact image sensor. Further, the sensor unit is arranged in pressure contact with the upper part of the conveying roller, and the weight of the sensor unit and a spring or the like can be added to bring the sensor unit into contact with it at an optimum pressure.

〔Example〕

The present invention will be described below with reference to the drawings of the embodiments. FIG. 1 is a sectional view of an image input device according to an embodiment of the present invention. In particular, the document conveying mechanism and the document detecting mechanism are shown. 21 is a conveyance roller, and there is only one. The transport roller 21 is made by winding a rubber material such as silicon rubber or fluorinated rubber around the iron core 22. Although not shown, the iron core 22 is attached to a bearing of the chassis. Reference numeral 23 denotes a guide plate, which is provided so that the document 24 is not caught. If the transport roller 21 is provided with a recess in the middle in the longitudinal direction and the guide plate 23 is passed therethrough, there is no risk of the original being caught. A document guide 25 is fixed to the sensor base 26. The document guide 25 is made of a material having rigidity such as stainless steel, and the sensor base 26 is made of a polymer material or a metal.
A light source 27 such as an LED bar light source for illuminating the document 24, a contact image sensor 28, and a rod lens array 29 for forming an erect image of the document on the contact image sensor 28 are attached to the sensor base 26. Has been. These sensor bases
The sensor unit 30 is formed by generically referring to 26 and those attached to the sensor base 26. The sensor unit 30 has a rotating shaft 31, and is attached to the chassis to which the transport roller 21 is attached. Then, the sensor unit 30 can rotate around the rotation shaft 31, and the document guide 25 comes into pressure contact with the conveyance roller 21.
In addition to the self-weight of the sensor unit 30, this pressing force is increased by pulling down the sensor unit 30 with a spring (not shown), for example. When the pressure is increased, the transportation of the document 24 is stabilized, but the friction load increases, so
Since it is necessary to increase the torque of the stepping motor, it is advisable to set it to the optimum pressure. This single transport roller
The document transport mechanism in which 21 and the document guide 25 are pressed against each other simultaneously inserts and ejects the document 24.

Next, the original detection mechanism will be described with reference to the same FIG. Reference numeral 32 is an infrared LED, 33 is a phototransistor, and these form a photointerrupter. In this embodiment, the infrared LED 32 is mounted on the chassis side and the phototransistor 33 is mounted on the sensor base 26, but the invention is not limited to this. When the document 24 passes between them, the light is blocked so that the presence or absence of the document 24 can be detected. At the detection stage, the light source 27 is turned on and the transport roller 21 is rotated, so that the document is guided by the document guide.
It is conveyed by being bitten between the 25 and the conveyance roller 21. Further, when the original 24 comes on the contact image sensor 28, the cue of the original can be known from the output of the contact image sensor 28, and this can be easily achieved by a known comparator. As described above, of the document detection mechanisms for presence / absence of the document and for the cueing, the cueing of the document uses the output of the contact image sensor, and thus no special sensor is provided.

[Effect of device]

As described above, according to the present invention, a single conveyance roller is used, and a document conveyance mechanism in which a document guide of a sensor unit having a rotary shaft is pressed against the conveyance roller, and a contact type image for reading the original of the originals. The original detection mechanism that uses the output of the sensor can significantly reduce the number of parts to provide a small and inexpensive image input device.Furthermore, since the sensor unit is provided above the transport roller, the original is set face up. It is possible to provide an image input device having various characteristics such as being able to be made and less affected by dust, and the effect is remarkably large.

[Brief description of drawings]

FIG. 1 is a sectional view of an image input device according to an embodiment of the present invention,
FIG. 2 is a sectional view of a conventional image input device. 21 …… Conveying roller, 22 …… Iron core 23 …… Guide plate, 24 …… Original 25 …… Original guide, 26 …… Sensor base 27 …… Light source 28 …… Contact type image sensor 29 …… Rod lens array 30 ...... Sensor unit 31 …… Rotary shaft 32 …… Infrared LED 33 …… Phototransistor

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Shinichi Miyazaki Inventor Shinichi Miyazaki 6-31-1 Kameido, Koto-ku, Tokyo Seiko Electronics Co., Ltd. (56) Reference JP-A-61-1167 (JP, A) JP SHO 62-104366 (JP, A) JP 62-183256 (JP, A) ACT 59-27660 (JP, U) ACT 59-48534 (JP, U) ACT 58-22353 (JP , Y2)

Claims (1)

[Scope of utility model registration request] 1. A document moving type image input device using a contact type image sensor, wherein a sensor base accommodating a document detecting sensor, a contact type image sensor, a rod lens array and a light source, and a sensor base fixed to the lower surface of the sensor base. A sensor unit that includes a document guide and is rotatable by providing a rotary shaft on the sensor base; a single conveying roller that has a concave portion at an intermediate position in the longitudinal direction and is in pressure contact with the document guide; A document feeding mechanism including a guide plate extending through almost the entire surface of the sensor unit and passing through the recess of the sensor unit, and turns on the light source when the document is detected by the document detecting sensor. When the original is conveyed to the position of the contact type image sensor by rotating the conveying roller, the output of the contact type image sensor is output. An image input device characterized in that it is possible to further know the beginning of the original.