KR20070018534A - Cassette for Image Forming Device - Google Patents

Abstract

The present invention relates to a cassette for an image forming apparatus including a document stacking unit on which a document is loaded and a document guide movably provided at both ends of the document stacking unit to prevent flow of documents. A document detection unit configured to detect the presence of a document; A document guide transfer unit for moving the document guide to a document guide position capable of contacting the document at a predetermined initial position when the document sensing unit detects a document; A transport time sensing unit for sensing a time required for the document guide to move from the initial position to the document guide position; And a document size discriminating unit for comparing the conveying time detected by the conveying time detecting unit with a predetermined conveying time table provided for each paper size to determine the document size loaded on the document loading unit. Thereby, it is possible to provide a paper feed cassette capable of automatically recognizing a paper size effectively with a simple configuration.

Description

Cassette for image forming apparatus {CASSETTE FOR IMAGE FORMING APPARATUS}

1 is a perspective view showing the configuration of a general copier,

2 is a schematic diagram schematically showing the structure of a cassette of a conventional copier;

3A and 3B are schematic views showing the configuration of the upper and lower surfaces of the cassette according to the present invention;

4 is a block diagram schematically showing the configuration of a cassette according to the present invention;

5 is an exemplary view illustrating an example of a transfer time table according to the present invention;

6 is a flowchart illustrating a document size automatic detection process of a cassette according to the present invention.

* Explanation of symbols for the main parts of the drawings

1: copier 200: cassette

210: loading plate 220: document guide

230: document detection unit 240: contact sensor

250: document guide transfer unit 251: pinion

253 rack 255 drive motor

260: transfer time detection unit 270: document size determination unit

The present invention relates to a cassette for an image forming apparatus, and more particularly, to a cassette structure for automatically detecting a paper size loaded in a cassette.

The image forming apparatus includes a laser printer, an LED printer, an ink jet printer, which forms an image on paper, a scanner that scans a document and outputs the image data, a scanner that transmits the scanned image data through a communication line, and an image of the document. There is a copying machine for scanning and copying into a plurality of documents, there is a multi-function product (MFP) including all the above-described functions.

1 is a perspective view showing an appearance configuration of a general copier 1. As shown in FIG. 1, the copier 1 has an automatic document feeder cassette (ADF) 20 for automatically supplying a loaded document to the scanning unit 10, and a stage glass unit for manually loading documents into the scanning unit ( An image forming unit (not shown) and an image forming unit (not shown) which form an image corresponding to an image of a document supplied through the automatic document feed cassette 20 on a plurality of copy papers. A control unit (not shown) for controlling the formation process.

Since the copying machine 1 makes copies of documents of various sizes, the paper feeding cassette 20 automatically detects the size of the document loaded on the upper surface and informs the controller (not shown). It includes a function to make a copy by selecting a copy paper corresponding to the size.

As shown in FIG. 2, the conventional document feed cassette 20 is provided separately with means (A, B, C) for detecting the size of the document loaded at a position corresponding to each standard document size. The size of the document was detected by the combination of signals detected by each means.

That is, when a document corresponding to the standard document A4 size is loaded in the document feed cassette 20, a contact signal is generated while the paper is contacted by the second paper detection means 25 provided at a position corresponding to the width of the paper. The third sheet detecting means 27 provided in a wide range of documents corresponding to the letter size does not generate a contact signal, so the size of the document is determined by the combination of the generated contact signals.

However, the paper feed cassette 20 of the conventional copier 1 should automatically match the type of document to be automatically detected in size and the number of paper detecting means, and detect the size of the document by a combination of a plurality of paper detecting means. Since the document size detection method is complicated.

In addition, the time required for detecting the paper size is increased by the complicated document size detection method, which further reduces the copying speed of the copier. On the other hand, since a number of paper detection means is required, there is a problem that the manufacturing cost of the copier increases.

Accordingly, it is an object of the present invention to provide a paper cassette for an image forming apparatus with a simple configuration and a short time for automatic document size detection.

The above object is, according to the present invention, in the cassette for an image forming apparatus comprising a document loading portion on which a document is loaded and a document guide movably provided at both ends of the document loading portion to prevent the flow of documents. A document sensing unit provided at a central portion of the upper surface of the unit for sensing the presence of documents; A document guide transfer unit for moving the document guide to a document guide position capable of contacting the document at a predetermined initial position when the document sensing unit detects a document; A transport time sensing unit for sensing a time required for the document guide to move from the initial position to the document guide position; And a document size discriminating unit for comparing the conveying time detected by the conveying time detecting unit with a predetermined conveying time table provided for each paper size to determine the document size loaded on the document loading unit. Is achieved.

Here, the document guide conveying unit, the lower end of the document loading portion extending in the vertical direction of the document guide and a transport shaft including a rack; A pinion engaged with the rack of the feed shaft; According to the detection of the document detection unit may be made of a drive motor for transmitting a driving force to the pinion.

Here, the transfer time sensing unit may calculate a drive pulse of the drive motor.

       The document guide may further include a paper contact sensor which determines whether contact with the document loaded in the document loading part is performed and controls the power of the driving motor.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

3A and 3B are perspective views showing the top and bottom surfaces of the paper feed cassette 200 according to the present invention, and FIG. 4 is a block diagram schematically showing the configuration of the paper feed cassette 200.

As shown in FIGS. 3A, 3B, and 4, the paper feeding cassette 200 according to the present invention is provided on both sides of the stacking plate 210 and the stacking plate 210 on which documents are stacked. It consists of a document guide 220 for preventing the flow of the loaded document, and a document guide transfer unit 250 for reciprocating the document guide 220 on the loading plate 210.

In addition, the transfer time detection unit 260 and the transfer time detection unit 260 for counting the time until the document guide 220 is in contact with the document and the pulse of the driving motor 255 by the document guide transfer unit 250 Document size discrimination unit 270 for determining the size of the document through the time and pulse detected by the.

The stacking plate 210 is manufactured in the shape of a plate into which a document to be copied can be stacked, and a document sensing unit 230 for detecting the presence of a document is provided at the center of the upper surface of the stacking plate 210 so that the paper guide 220 can move. 215.

 When the document is loaded on the upper surface of the loading plate, the document detecting unit 230 notifies the document guide transfer unit 250 which will be described later to signal that the document is loaded. Document detection unit 230 is preferably loaded in a position that can detect the presence of any size paper is loaded on the loading plate 210, it may be implemented as a photo sensor, a contact sensor, a pressure sensor, etc. .

The movement hole 215 is formed to move the rack 253 of the document guide moving part 250 provided on the lower surface of the loading plate 210 so that the document guide 220 can move. The moving hole 215 is preferably formed to be narrower than the width of the rack 253.

The document guide 220 is provided to be movable between the document guide position (Y) from the initial position (X) of the loading plate 210, so that the document loaded on the loading plate 210 does not flow by disturbance Support both ends. The document guide 220 is preferably formed of a length sufficient to support the document.

The document guide 220 includes a contact sensor 240 for detecting the contact with the document inside the contact with the document. When the document guide 220 is in contact with the document when the document guide 220 moves from the initial position X to the document guide position Y, the contact sensor 240 outputs a signal indicating that the document is in contact with the document to the document guide transfer unit 250 described later.

The contact sensor 240 may be implemented as a pressure sensor and a micro switch to detect an increase in the load of the driving motor for transferring the document guide when the contact with the document is in contact with the document. Other known techniques for determining the contact can be used.

As shown in FIG. 3B, the document guide conveying unit 250 is formed to be engaged with the pinion 251 by extending in the horizontal direction of the pair of document guides and the pinion 251 provided on the lower surface of the stacking plate 210. It consists of a pair of rack 253 and a drive motor 255 for transmitting a driving force to the pinion 251.

The driving motor 255 is rotated when a signal indicating that the document is loaded on the loading plate 210 from the document detecting unit 230 is rotated, and the pinion 251 connected to the driving motor 255 is also rotated. On the other hand, when the document guide 220 is contacted with the document from the contact sensor 240, the driving motor 255 stops the rotation and the pinion 251 also stops so that the transfer of the feed guide stops.

The pinion 251 is provided at the center of the lower surface of the loading plate 210 to drive the rack 253 extending at both ends of the loading plate 210.

The rack 253 extends in the horizontal direction of the document guide 220 and is engaged with the pinion 251. When the pinion 251 is rotated by the drive motor 255, the rack 253 meshes with the pinion 251 and moves to the document guide position (Y).

The transfer time detection unit 260 includes a timer and a counter of a measurer to measure a time required when the document guide 220 moves from the initial position X to the document guide position Y and pulses of the driving motor to be described later. The size determining unit 270 informs. The transfer time detection unit 260 counts the time required from when the drive motor 255 starts to rotate until the drive motor 255 stops by using a timer, or the drive motor 255 starts to rotate. Pulses of the rotating drive motor from the time when the motor stops until the motor stops can be counted using a counter.

The document size determination unit 270 stores the time or pulse detected by the transfer time detection unit 260 for each document size and the time and pulse required for the document guide 220 to contact the document, as illustrated in FIG. 4. The paper size is determined by comparison with the transfer time table 300.

That is, for example, when the paper transfer guide 220 informs the transfer time detecting unit 260 that the time required for moving from the initial position X to the document guide position Y is 2 seconds, the document size discriminating unit 270. ) Detects that the document loaded on the stacking plate 210 is a standard paper A4 size.

The operation of the copier using the cassette 200 according to the present invention having such a configuration will be described in detail with reference to FIGS. 1, 3A, and 5.

First, the user loads a document to be copied in the automatic document feeder 200 of the copier 1 and applies a copy signal through the input unit 60. The document detecting unit 230 of the stacking plate 210 determines whether the document to be copied and notifies the document guide transfer unit that the document is loaded (S10).

The drive motor 255 of the document guide transfer unit 250, which has received a signal that the document is loaded on the loading plate 210 by the document detection unit 230, starts to rotate and pinion 251 interlocked with the drive motor 255. Also rotates. The rack 253 meshed with the pinion 251 by the rotation of the pinion 251 moves from the initial position X to the paper guide position Y (S20).

On the other hand, when the drive motor 255 starts to rotate, the transfer time detection unit 260 operates a timer and a counter to count the transfer time and pulses required until the drive motor 255 stops (S30).

When the document guide 220 moves, the contact sensor 230 detects whether the document is in contact with the document (S40), and when the document guide 220 is in contact with the document, informs the result of the driving motor 255. The driving motor 255, which is authorized to contact the document guide 220 and the document through the contact sensor 230, stops rotating (S50). At the same time, the transfer time detection unit 260 stops the operation of the timer and the counter, and informs the document size determination unit 270 of the time measured by the timer and the pulse measured by the counter.

The document size discriminating unit 270 determines the size of the loaded document by comparing the time and pulse received with the transfer time table 300 (S60).

The determined document size is notified to a controller (not shown) of the copier, and the controller (not shown) controls the paper feeders 40 and 50 to feed the print paper corresponding to the document size.

As described above, according to the present invention, the size of the document can be effectively determined by the interaction between the document sensor and the contact sensor of the document guide provided on the stacking plate, eliminating the paper sensing means used for each paper type. .

Through this, the capacity of the allocation port allocated by the control unit to recognize the sensing means can also be reduced and the sensing time can be shortened, thereby improving the copy speed.

In addition, since expensive sensors are not used, manufacturing cost can be reduced.

As described above, according to the present invention, the size of the document can be determined simply and effectively by the interaction between the document detection sensor provided on the loading plate and the contact sensor of the document guide. There is provided a cassette for an image forming apparatus.

Claims (4)

       A cassette for an image forming apparatus, comprising: a document loading portion into which a document is loaded, and a document guide movably provided at both ends of the document loading portion to prevent the flow of documents;       A document sensing unit provided at a central portion of the upper surface of the document stacking unit to detect the presence or absence of a document;       A document guide transfer unit for moving the document guide to a document guide position capable of contacting the document at a predetermined initial position when the document sensing unit detects a document;       A transport time sensing unit for sensing a time required for the document guide to move from the initial position to the document guide position;       And a document size discriminating unit for comparing the conveying time detected by the conveying time detecting unit with a predetermined conveying time table provided for each paper size to determine the document size loaded on the document loading unit.        The method of claim 1,        The document guide transfer unit,        A transport shaft extending in a vertical direction of the document guide at a lower end of the document loading part and including a rack;       A pinion engaged with the rack of the feed shaft;       And a drive motor for transmitting a driving force to the pinion in response to the detection of the document detection unit.        The method of claim 2,        And the transfer time sensing unit calculates a driving pulse of the driving motor.        The method of claim 1,        The document guide,       And a document contact sensor for controlling the power supply of the driving motor by determining whether the document is in contact with the document loaded in the document loading unit.

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