JP2550880Y2 - Image reading device - Google Patents

Description

[Detailed description of the invention]

[0001]

This invention reads a plurality of originals at a high speed and stores the image data in an image memory, a printer,
The present invention relates to an image reading device for sending out to image data input means such as a facsimile device.

[0002]

2. Description of the Related Art In recent years, as this kind of image reading apparatus,
After reading a plurality of sheet-shaped originals at high speed, converting the read signals into digital signals, performing necessary processing to generate image data, and using the image data in a database, an image memory of a printer, or a communication line. 2. Description of the Related Art An image reading device such as a high-speed sheet feed scanner device (hereinafter, referred to as a scanner device) that transmits an image data to an image data input device serving as a transmission / reception device of a facsimile device or the like via the other party has become popular.

In particular, the development of high-speed line image sensors (CCD) and contact image sensors (CIS) has recently made it possible to read documents at high speed.
However, in the image data input unit, processing such as compression, decompression, transmission, and compounding of the transmitted image data takes time, and the image data input unit may not be able to catch up with the original reading speed. Therefore, a stop request command is issued from the image data input unit to the image reading unit to stop the temporary reading operation.

FIG. 4 is a diagram schematically showing a document conveying / reading section of a conventional image reading apparatus. In FIG. 4, reference numeral 1 denotes a plurality of documents set on a document table, reference numeral 2 denotes a separating / transport roller for separating and transporting one document from the plurality of documents, and a forward roller 2a transports the document. The document is transported while rotating in the direction, and the retard roller 2b rotates in the direction opposite to the transport direction, thereby preventing double feeding of the document and separating one document. Reference numeral 3 denotes a leading edge detection sensor that detects the leading edge of the document that is separated and conveyed. A movable lever 3a receiving an upward force by a spring (not shown) is driven by a weight of the document about an axis 3c. When rotated,
By cutting off the light beam of the photo interrupter 3b, the leading edge of the document is detected. Reference numeral 4 denotes a feed roller for conveying a document sent from the separation / conveyance roller 2 to a reading position. Reference numeral 5 denotes a discharge roller that discharges the document that has been read. Reference numeral 6 denotes an end detection sensor for detecting that the document has separated from the separation / conveyance roller 2. When the end of the document passes through this sensor, the movable lever 6 is detected.
The end of the document is detected by changing from a state in which the photo-interrupter 6b is shielded from light by a to a state in which light is incident.

Next, the operation of the configuration shown in FIG. 4 will be described. First, when the document 1 is separated and conveyed by the separation / conveyance roller 2, the end detection sensor 6 is turned on, and then the front end detection sensor 3 is turned on. From the leading end detection position A where the leading end detection sensor 3 is turned on, the document is transported to the reading position B by a distance Lr. The calculation of this distance Lr
Conveyance rollers 2 and calculated in terms of the number of pulses of the pulse signal to the stepping motor (not shown) for driving the feed roller 4. At the reading position B, the document is read by a reading image sensor (not shown) while being transported at a predetermined transport speed. The document that has been read is discharged by the discharge roller 5.

[0006] In this case, if the distance between the conveyed documents is too long, not only the scanning efficiency is reduced, but also in the case of facsimile transmission, the billing time without data transmission increases. Become. Therefore,
Even if the previous document is still being read, the next document is separated and conveyed from the separation / conveyance roller 2 at a predetermined interval.

On the other hand, when the processing speed of the image data cannot keep up with the document reading speed in the image data input means (not shown), a read stop request command is sent from the image data input means to the image reading apparatus. In this case, in order to avoid the deterioration of the image quality or from the viewpoint of software processing of the control system, the reading of the document currently being read is completed, and before the next document is drawn into the separation / conveyance roller 2, It is desirable to stop the driving of the separation / transport roller 2. However, when the reading of the current document is completed, the next document passes the leading edge detection position A. For this reason, an end detection sensor 6 is provided after the separation / transport roller 2 to detect the end of the document currently being read, and drives the separation / transport roller 2 immediately after the document is separated from the separation / transport roller 2. The document is stopped and the conveyance of the next document is stopped.

[0008]

However, in the above-mentioned conventional example, it is necessary to provide a special termination detection sensor, which not only causes an increase in cost but also an obstacle to downsizing of the apparatus in order to secure a space for this sensor. There was a problem of becoming.

The present invention is intended to solve such a conventional problem, and does not provide a sensor for detecting the end of the document. An object of the present invention is to provide an image reading apparatus capable of stopping driving of a separation / conveyance roller before drawing in.

[0010]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a separating means for separating one original from a plurality of originals, a conveying means for conveying the original, and the conveyed original. Detecting means for detecting the leading edge of the document, reading means for reading the conveyed document to generate image data, transmitting and receiving means for sending the image data to the outside and receiving a signal from the outside, Control means for controlling the driving of the means, and storage means for storing a predetermined distance value , wherein the control means transmits the image data from the transmission / reception means.
When a stop request command for image data transmission is received,
Means for detecting the leading edge of the document,
When a predetermined distance value stored in the storage means is reached
Thus, a stop means for stopping the driving of the separation means is provided .

[0011]

According to the present invention, when a stop request for image data transmission is received from the transmission / reception means according to the above structure, the conveyance distance after the detection means has detected the leading edge of the document has reached a predetermined distance. Since the driving of the separating means is stopped, the driving of the separating / transporting roller can be stopped before the next document is pulled in without providing a separate sensor for detecting the end of the document.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows the structure of a document conveying / reading unit in the image reading apparatus of the present embodiment. As shown in FIG. 4, reference numeral 1 denotes a plurality of documents set on a document table.
Reference numeral 2 denotes a separation / conveyance roller as separation / conveyance means for separating / conveying one document from the plurality of documents, and a forward roller 2a constitutes conveyance means for rotating the document in the conveyance direction to convey the document. The retard roller 2b rotates in a direction opposite to the conveying direction to prevent double feed and constitute a separating unit for separating one document. Reference numeral 3 denotes a leading edge detection sensor as a detecting means for issuing a detection signal when the leading edge of the separated and conveyed document reaches the leading edge detection position A, and is a movable lever which receives an upward force by a spring (not shown). When the document 3a rotates about the axis 3c by the weight of the document, the leading end of the document is detected by blocking the light beam of the photo interrupter 3b. Reference numeral 4 denotes a feed roller that conveys the document sent from the separation / conveyance roller 2 to the reading position B. Reference numeral 5 denotes a discharge roller that discharges the document that has been read.

FIG. 2 is a block diagram of a system configuration to which the image reading apparatus of the present embodiment is applied. 2, reference numeral 10 denotes a CPU as control means for controlling the scanner device 20, reference numeral 11 denotes a document presence / absence sensor for detecting that a document is set on a document table, and reference numeral 12 denotes a leading end of the document. This is a tip detection sensor (same as reference numeral 3 in FIG. 1). Reference numeral 13 denotes a separation / conveyance roller drive unit that rotationally drives the separation / conveyance roller, and reference numeral 14 denotes a feed roller drive unit. Reference numeral 15 denotes a document reading unit as reading means for reading a document, and reference numeral 16 denotes a discharge roller driving unit that discharges the read document. Reference numeral 17 denotes an operation unit for inputting a command to start a document reading operation, a command such as a document size, a reading linear density, and the like, and data. These are CPU 10 and bus 1
9.

Reference numeral 30 denotes an image data input device as a transmission / reception means for inputting image data from the scanner device 20 and transmitting the input image data to the outside, and is connected to the scanner device 20 by an interface bus 23. . Reference numeral 31 denotes a signal line for sending a read stop request command to the CPU 10.

Next, the operation of this embodiment will be described with reference to FIG.
A description will be given based on a flowchart showing the operation performed by the PU 10. First, the length of the original in the reading direction, that is, the transport direction of the original, by the operation of the operator or automatically,
It is stored in a memory (not shown) in the CPU 10 in advance.
In the present embodiment, however, the stored document length is a predetermined distance value from the time when the document 1 reaches the leading edge detection position A in FIG. 1 until the document 1 separates from the separation / conveyance roller 2. It is stored as the length Ld.

When a document is set on the document table, the separation / transport roller 2 is driven (step S1), and the feed roller 4 is driven (step S2). Thereafter, it is determined whether or not the tip detection sensor 3 is turned on (step S).
3) It is determined whether or not the conveyance length X of the document from the leading edge detection position A has reached the distance Lr to the reading position B (step S4), and if so, reading of the document is started. (Step S5). During this reading, it is determined whether or not there is a read stop request command from the image data input device 30 (step S6). If there is no stop request command, the reading operation is continued until the reading is completed.

If there is a stop request command, it is determined whether or not the transport length X has reached the stored planned length Ld (step S7), and when it has reached, the separation / transport roller 2 is driven. It stops (step S8).

As described above, the planned length until the document is separated from the separation / conveyance roller 2 is stored in advance, and when the document is conveyed, the conveyance length is compared with the planned length.
The end detection sensor in the conventional example can be omitted.

In the above embodiment, a separate signal line is provided for the signal of the stop request command. However, the stop request command may be transmitted using an image data interface bus.

[0021]

As described above, in the image reading apparatus according to the present invention, as is apparent from the above-mentioned embodiment, when the image data transmission stop request command is received from the transmission / reception means, the detection means sets the original to the original. When the transport distance from the detection of the leading edge reaches a predetermined distance, the driving of the separation unit is stopped.Therefore, without providing a sensor for detecting the end of the document, the separation unit is separated before the next document is pulled in. The driving of the conveyance roller can be stopped to stop the conveyance of the next document. As a result, there is no need to provide a sensor for detecting the end of the document, so that the cost can be reduced and the effect of realizing the downsizing of the apparatus can be obtained.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a document conveying / reading unit in an embodiment of an image reading apparatus of the present invention.

FIG. 2 is a system configuration diagram to which the image reading device of the present invention is applied.

FIG. 3 is a flowchart of an operation of document conveyance performed by a CPU in FIG. 2;

FIG. 4 is a configuration diagram of a document conveying / reading unit of a conventional image reading apparatus.

[Explanation of symbols]

 Reference Signs List 1 original 2a forward roller (conveying means) 2b retard roller (separating means) 3 leading edge detection sensor (detecting means) 4 feed roller 5 discharge roller 10 CPU 30 image data input device (transmitting / receiving means)

Claims (2)

(57) [Scope of request for utility model registration] A separating unit that separates one original from a plurality of originals; a conveying unit that conveys the original; a detecting unit that detects a leading end of the conveyed original; and a reading of the conveyed original. Reading means for generating image data by transmitting the image data, transmitting and receiving means for transmitting the image data to the outside and receiving a signal from the outside, control means for controlling the driving of the separating means, and storing a predetermined distance value And a control unit that, when receiving the image data transmission stop request command from the transmission / reception unit, sets the transport distance after the detection unit detects the leading end of the document to the control unit. Stop means for stopping the driving of the separation means when the predetermined distance value stored in the storage means is reached .
Characterized in that that, the image reading apparatus. 2. The storage unit stores, as the predetermined distance value, a length from when the detecting unit detects the leading end of the document to when the document leaves the separating unit. An image reading device according to claim 1.