JPH0535946B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a document conveying device that conveys documents one after another in order to continuously transmit a plurality of documents in a calligraphic information transmitting device such as a facsimile transmitting device.

BACKGROUND ART As shown in FIG. 2, a conventional device of this type includes a document detection A detector 2 disposed slightly in front of a document input position to detect the presence or absence of a document 1 to be sent.
, a document detection B detector 3 located slightly in front of the document reading position to detect the start and end edges of the transmitted document 1, and document transport rollers 4 and 5 that transport the document from the input position to the reading position. and a document reading device 6 that reads the document and converts it into an image signal.
A document reading roller 7 that supports and conveys a document between the document reading device 6 and a drive motor 8 that is connected to the document conveyance roller 5 and the document reading roller 7 via a drive system and drives both rollers 5 and 7. , a connection device 9 such as a clutch disposed between the drive motor 8 and the document transport roller 5 , a drive control circuit 10 that controls the drive motor 8 , and a connection device 9 that controls the drive motor 8 from the drive control circuit 10 as necessary. Counts the drive signals applied to the drive control circuit 10 and the amount of document feeding by the conveyance roller or reading roller, and outputs control signals to the drive control circuit 10 and the connection device 9, respectively, when the value reaches a certain value. It had a counting circuit 11.

The operation of this document conveying device when a plurality of documents are continuously sent out will be described. When the document detection A detector 2 detects the presence of a document and the transmission operation is started after the connection device 9 is connected, the drive control circuit 10 sends a constant speed drive signal to the drive motor 8.
This causes the document conveying rollers 4 and 5 to rotate at a constant speed, thereby conveying the document 1 toward the document reading device 6 at a constant speed. When the document detection B detector 3 detects the starting edge of the conveyed document, this detection signal causes the counting circuit 11 to start counting.
starts counting the drive signals output from the drive control circuit 10 to the drive motor 8. On the other hand, the original continues to be fed at a constant speed by the original transport rollers 4 and 5, which still rotate at a constant speed. When the count value of the counting circuit 11 reaches the distance between the document detection B detector 3 and the reading position of the document reading device 6 (hereinafter referred to as M), the counting circuit 11 controls the drive control circuit 10. In contrast, a control signal for ending counting is output. When the drive control circuit 10 receives this signal from the counting circuit 11, it converts the signal output to the drive motor 9 from a constant speed drive signal to a drive signal corresponding to the reading speed by the document reading device 6. At this time, when the starting edge of the document is fed into the document reading roller 7, the connecting device 9
A control signal for cutting is output to the document transport rollers 4 and 5, and the document conveying rollers 4 and 5 are brought into a non-driving state. In this state, the original is read and sent. During this document sending, when the end of the document is detected by the document detection B detector 3, the counting circuit 11 similarly starts counting. Counting circuit 11
When the count value becomes M, the trailing edge of the document has reached the reading position, and the reading operation is ended. Note that if the next document is detected by the document detection A detector 2, and the distance from the end of the previous document to the start of the next document exceeds M, a connection is made from the counting circuit 11. A control signal indicating connection is output to the device 9, the document conveying rollers 4 and 5 are connected to the drive motor 8, and their rotation is placed under the control of the drive control circuit 10. Therefore, the next document located at the document conveyance rollers 4 and 5 is sent toward the reading device. below,
By repeating similar operations, multiple sheets of originals are continuously transmitted.

Problems to be Solved by the Invention However, according to this configuration, after the trailing edge of the previous document has completely left the document conveying rollers 4 and 5, the starting edge of the next document is conveyed by the document conveying rollers 4 and 5. It is necessary to maintain a minimum distance M between the two originals caused by the start of the process, and to do this, the connecting device 9 and its control are required, which makes the device configuration complicated and its control also complicated. There was a problem.

The above problem arises for the following reasons. First, in the above configuration, the reason why the distance between two originals must be set to a minimum of M is that if we consider a case where the distance between them is less than M, then the first original is sent out. When the end of the document is detected by the document detection B detector 3, the counting circuit 11 starts counting the output from the drive control circuit 10, and when it reaches the specified value M, the counting circuit 11 starts counting the output from the drive control circuit 10. After the original reading is completed, preparation for reading the next original is started. In this case, 1
When the end of the original sheet reaches the reading position of the original reading device 6, the starting edge of the next original has already passed the original detection B detector 3, so the counting circuit 11
Even if the counting operation for the second document is started immediately at this point, since the position of the starting edge of the document is not clear from the beginning, it becomes impossible to move the document to the reading position accurately. Put it away. For this reason, it is necessary to ensure a minimum distance M between the two transmission originals.

In order to satisfy the above conditions, it is necessary to provide a connecting device 9 like the one described above, but if this device is attached, the device configuration becomes complicated, the overall volume increases, and the material cost increases. The disadvantage was that it was also expensive.

The present invention has been made in view of the above-mentioned problems, and when sending out a plurality of documents, it is possible to minimize the It is an object of the present invention to provide a document conveying device that can accurately grasp the starting edge position of each document and completely feed the documents with a limited equipment configuration.

Means for Solving the Problems The present invention provides a reading means for reading an original, a first original conveying means for conveying the original to the reading means, an original detecting means for detecting the leading and trailing edges of the original to be read, a second document conveyance means located upstream in the conveyance direction from the document detection means and whose conveyance speed is slower than the first document conveyance means; and a counter for counting the document feed amount M from the document detection means to the reading means. means, storage means for storing the counted value _M1 of the counting means from when the document detecting means detects the trailing edge of the document to be read in advance until the leading edge of the document to be read next; When the trailing edge of the original to be read reaches the reading means by the completion of counting by the counting means, the storage means stores the feeding amount M of the original to be read next from the original feeding amount M to be counted by the counting means. The configuration is such that counting is started as a value M- _M1 obtained by subtracting the count value _M1 .

Effects According to the present invention, with the above-described configuration, when a plurality of originals are sent out in succession, when the original detecting means arranged before the reading position detects the end of the original being sent, the counting means detects the original. When the feeding amount starts to be counted and the counted value reaches a predetermined value, that is, when the end of the document reaches the reading position, the document reading operation by the reading means is ended. Since the conveyance roller continues to rotate, when the next document is being fed and the leading edge of the document is detected by the document detection means, the count value of the counting means at that time is outputted to the storage means and stored by the detection signal. When the end of the previous document reaches the reading position, that is, when the counting means counts up a predetermined count value, the stored value is read out from the storage means to the counting means, and the counting means reads out the stored value. By starting counting the starting edge of the next document based on , it is possible to accurately determine the position of the starting edge of the second and subsequent documents. This eliminates the need for a configuration in which a large gap is left between the scanner and the document, a predetermined value is counted from the detection of the end of the document during scanning, and after that, the start of the next document is detected and a new count is started. , it becomes possible to omit a connecting device such as a clutch disposed between the drive motor and the document conveyance roller, which is necessary to increase the distance between the document being read and the subsequent document.

Examples Examples of the present invention will be described below. FIG. 1 shows a schematic configuration of a document conveying device according to an embodiment of the present invention. This document conveying device includes a document detection A detector 2 located slightly in front of the document input position to detect the presence or absence of the document 1 to be sent, and a document reading device 2 to detect the start and end edges of the document 1. A B-detector 3 for detecting an original placed slightly in front of the original position, original transport rollers 4 and 5 that transport the original from the input position to the reading position, and an original reading device 6 that reads the original and converts it into an image signal. A document reading roller 7 that supports and conveys a document between the document reading device 6 and a pulse motor that is connected to the document conveyance roller 5 and the document reading roller 7 via a drive system and drives both rollers 5 and 7. a drive motor 8, a drive control circuit 10 that controls the drive motor 8, and a drive signal (pulse) applied from the drive control circuit 10 to the drive motor 8 as necessary, and counts the drive signal (pulse) applied to the drive motor 8, and therefore controls the transport roller or reading roller. The apparatus includes a counting circuit 11, etc., which counts the amount of document feed due to the amount of the original and outputs a control signal to the drive control circuit 10 when the value reaches a certain value. No connecting device is provided between the drive motor 8 and the document conveyance roller 5 to separate them. Instead, the counting circuit 11
A storage circuit 12 for storing the counted value is connected to. This memory circuit 12 is stored in the memory circuit 12 so that while the previous document is being read during transmission transmission, the starting edge of the next document is in the document detection B.
Counting circuit 1 is activated by the detection signal when it reaches detector 3.
The count value of 1 is input and stored, and the count value of 1 is input and stored.
1 causes the counting circuit 11 to read out the stored value using an output signal when counting a predetermined count value.

The operation of the document conveying device configured as described above when continuously feeding a plurality of documents will be described below.

When the document detection A detector 2 detects the presence of a document and enters the transmission operation, the drive control circuit 10 outputs a constant-speed drive signal to the drive motor 8 to control the document conveyance rollers 4, 5, and document reading roller 7 at a constant speed. The document is rotated at a constant speed and the document is conveyed at a constant speed in the direction of the reading position. Continuing this operation, the document detection B detector 3 detects the document 1 being conveyed.
When the starting edge of the drive control circuit 10 is detected, the counting circuit 11 starts operating based on the detection signal and starts counting the drive signals output from the drive control circuit 10. Counting circuit 11
When the count value reaches the distance between the document detection B detector 3 and the reading position of the document reading device 6 (hereinafter referred to as M), the counting circuit 11 sends a control signal to the drive control circuit 10 to end counting. The counting operation ends at the same time as the output. The drive control circuit 10 converts the output signal of the drive motor 8 from constant speed drive to a drive signal corresponding to the reading speed of the document reading device 6 . As a result, the original 1 is being read and sent by the original reading roller 7 at a speed corresponding to the reading speed. When the document continues to be sent out in this manner and the document detection B detector 3 detects the end of the sent document, the counting circuit 11 starts counting in the same manner as described above. In this state, while sending out the previous document, the document detection B detector 3 continues to confirm the presence of the starting edge of the next document. Even while the document reading roller 7 is rotating and feeding the document being read, the document conveyance rollers 4 and 5 are both rotating, and therefore feeding the next document. At this time, considering the case where the interval between the end of the document being read and the start of the next document is smaller than the above-mentioned M, the counting by the counting circuit 11 does not end before the sending of the previous document ends. Before that, the document detection B detector 3 detects the starting edge of the next document. This detection signal is used to store the count value of the counting circuit 11 at that point in time, that is, the value corresponding to the distance between the document detection B detector 3 and the end of the previous document at that point in time (hereinafter referred to as _M1 ). 12 to be memorized. On the other hand, the counting circuit 11 continues counting. Next, when the end of the previous document reaches the reading position, that is, when the counting circuit 11
When the count value of reaches the predetermined value M, the counting circuit 11
A control signal for ending counting is output to the drive control circuit 10, and the counting operation is ended. The drive control circuit 10 converts a drive signal corresponding to the reading speed into a constant speed drive signal and outputs the same to the drive motor 8 . At this time, the starting edge of the next original has already exceeded the B detector 3 for detecting the original by a distance corresponding to the count value M - M ₁ , so if the counting operation in the counting circuit 11 is performed from the beginning, the starting edge of the next original will be cannot be moved to the reading position accurately. Therefore, in order to prevent this, the value _M1 stored in the storage circuit 12 is read out, and counting in the counting circuit 11 is started based on this value. That is, the counting circuit 11 starts counting from a count value (M-M ₁ ) corresponding to the distance that the starting edge of the next document has moved beyond the B-detector 3 for detecting the document, and
When the count value reaches M, it can be determined that the starting edge of the next document has accurately arrived at the reading position. By repeating this operation, continuous transmission becomes possible.

In addition, in order to prevent the end of the previous document and the start of the next document from being fed in an overlapping manner, causing a detection error by the document detection B detector 3, the conveyance speed of the document conveyance rollers 4 and 5 is adjusted by the document reading roller 7. The speed should be slower than the transport speed so that a gap is created between the two. At this time, it is necessary to correct the count value in the counting circuit 11 depending on whether the original is transported by the original transport rollers 4 and 5 or the original reading roller 7. In addition, a slip clutch is installed between the document conveyance roller 5 and the drive motor 8 to prevent excessive tension from being applied to the document when the document is conveyed by both the document conveyance rollers 4 and 5 and the document conveyance and reading roller 7. It is preferable to intervene. Further, in the above embodiment, the counting circuit 11 counts the drive signal from the drive control circuit 10 to count the amount of document feed, but instead of this, the number of rotations of the document transport roller and the document reading roller is measured and the document is fed. The amount may be counted.

Effects of the Invention As is clear from the above description, the present invention provides a reading means for reading an original, a first original transporting means for transporting the original to the reading means, and an original for detecting the leading and trailing edges of the original to be read. a detection means, a second document conveyance means located upstream of the document detection means in the conveyance direction and whose conveyance speed is slower than the first document conveyance means, and a document feed amount M from the document detection means to the reading means. a storage means for storing the counted value _M1 of the counting means from when the original detecting means detects the trailing edge of the original to be read in advance to when the leading edge of the original to be read next is detected; ,
When the trailing edge of the original to be read in advance reaches the reading means after the counting of the counting means is completed, the storage means calculates the feeding amount M of the original to be read next from the feeding amount M of the original to be counted by the counting means. By configuring to start counting as a value M - M ₁ obtained by subtracting the stored count value M ₁ , the document detection means detects the end of the document being read, and the detection circuit starts counting. When the starting edge of the next original reaches the original detecting means later and before the counting is completed, the memory circuit stores the counted value of the counting means at that time, and the ending edge of the previous original reaches the reading position and the counting by the counting means is started. When the process is completed, the stored value is read out to the counting means, and based on this, the counting means starts counting the starting edge of the next document, making it possible to accurately grasp the position of the starting edge of the second and subsequent documents. , Therefore, the two before and after
There is no need to keep the distance between sheets of originals constant, and there is no need to specify a minimum value.
This has the effect of simplifying the device configuration, without requiring a connecting device such as a clutch for intermittent power transmission between the drive motor and the document conveyance roller, as in the prior art.

[Brief explanation of drawings]

FIG. 1 is a block diagram schematically showing a document conveying device according to an embodiment of the present invention, and FIG. 2 is a block diagram schematically showing a conventional document conveying device. 1...Document, 3...B detector for document detection, 4,
5...Document transport roller, 6...Document reading device, 7
...Document reading roller, 8...Drive roller, 10...
... Drive control circuit, 11 ... Counting circuit, 12 ... Memory circuit.

Claims (1)

[Claims] 1. A reading means for reading a document, a first document conveying means for conveying the document to the reading means, a document detecting means for detecting the leading edge and a trailing edge of the document to be read, and a document detecting means located upstream of the document detecting means in the conveying direction. A second document conveying means whose conveyance speed is slower than the first document conveying means, a counting means for counting the document feed amount M from the document detecting means to the reading means, and the document detecting means are arranged in advance. storage means for storing the count value _M1 of the counting means from detecting the trailing edge of the document to be read until detecting the leading edge of the document to be next read; The feeding amount M of the document to be read next when reaching the reading means upon completion of counting is a value M- obtained by subtracting the count value _M1 stored in the storage means from the feeding amount M of the original to be counted by the counting means. A document conveying device characterized in that counting starts as _M1 .