JP2022023753A - Conveyance device, image reading device, and image forming device - Google Patents

Abstract

To accurately detect a sheet at a prescribed position of a sheet tray in a conveyance device.SOLUTION: The conveyance device comprises: a sheet tray on which sheets are placed; and conveyance means for conveying the sheets placed on the sheet tray. The sheet tray includes first detection means for detecting placing of the sheets. The conveyance device comprises second detection means for detecting location of tips of the downstream-side sheets on the downstream side of the conveyance means in a sheet conveying direction.SELECTED DRAWING: Figure 2

Description

The present invention relates to a transport device, an image reader and an image forming device.

In an image reading device that reads a recording medium on which a document is represented as an image, there is an image reading device provided with an automatic document transporting device (ADF: Auto Document Feeder) for automatically transporting the document to a scanning position. Further, an image forming apparatus for forming a document read by an image reading apparatus on a recording medium is also known.

It is known that the ADF is provided with a document tray (paper tray) on which documents are placed, and the document tray is provided with a sensor for detecting that a document has been set. When the sensor detects a document, the ADF takes the document with a pickup roller (conveyor roller; transport roller) provided near the paper feed port of the ADF and sends it to the image reader. In order to prevent the pickup roller from spinning, it is necessary to accurately detect whether or not the document is set at a position on the document tray that can be captured by the pickup roller.

For example, there is a technique in which two detection means are provided on a document tray (see, for example, Patent Document 1). In the technique disclosed in Patent Document 1, two types of detection means, a manuscript detection sensor and a weight detection unit, are provided, the presence or absence of a manuscript is detected by the manuscript detection sensor, and then the weight is detected when the presence or absence of a manuscript is detected. The unit detects whether the weight of the mounted document is heavy or light by the pressure, and changes the ascending speed of the document tray according to the weight of the document.

Even if the technique disclosed in Patent Document 1 is used, it may not be possible to determine whether or not the document placed for automatic transportation is set at a position where it can be taken in by the pickup roller.

If this is to be detected by an optical sensor on the surface of the document tray, it must be installed at the position closest to the pickup roller of the document tray, that is, at the position of the tip of the document. Then, for example, if the original has a chipped state such as a punched hole, it may not be detected.

Further, for example, there is a case where the document is detected by a filler provided in the paper feed port instead of the optical sensor on the document tray. However, in the case of the type in which the document tray moves up and down, the filler must be lengthened so that the document tray can be detected even when it is in the lowest position. In that case, peripheral parts cannot be arranged in the operating range of the filler, the strength of the peripheral structure is lowered, and the filler itself becomes large.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a technique for accurately detecting paper at a predetermined position on a paper tray.

In order to solve the above technical problem, one aspect of the present invention is a transport device including a paper tray on which paper is placed and a transport means for transporting the paper placed on the paper tray.
The paper tray has a first detection means for detecting that the paper is placed, and the transport device has the tip of the paper on the downstream side in the paper transport direction on the downstream side of the transport means. It is characterized by being provided with a second detection means for detecting the above.

According to the present invention, the paper at a predetermined position on the paper tray can be detected with high accuracy.

It is a schematic block diagram of the image forming apparatus of embodiment of this invention. (A) is a cross-sectional view of a main part of the transport device according to the embodiment of the present invention, (b) is an enlarged view of a document tray portion of the transport device, and (c) is a view of the document tray portion of the same document tray. It is a schematic top view. It is a hardware block diagram of the control part of the Embodiment of this invention. It is a functional block diagram of the control part of the Embodiment of this invention. It is a flowchart of the document detection transport process of embodiment of this invention. (A) to (c) are explanatory views for explaining the document detection and transport process of the embodiment of the present invention. (A) to (c) are explanatory views for explaining a modification of the detection means of embodiment of this invention. It is a schematic block diagram of the image forming apparatus of the modification of embodiment of this invention.

Hereinafter, embodiments of a transport device, an image reading device, and an image forming device according to the present invention will be described with reference to the drawings.

In this embodiment, two document detecting means are provided in the document tray section. The two document detecting means are an optical first detecting means provided on the document tray on the upstream side in the transport direction in front of the transport means (convey roller; pickup roller) and a downstream side in the transport direction ahead of the transport means. It is a filler contact type second detection means provided in the above. In the present embodiment, first, the first detecting means detects that the document has been placed, then the document tray is raised, and the second detecting means detects the tip of the document by raising the document tray.

As a result, there are no restrictions on the placement position of the first detection means. Therefore, it is not necessary to arrange the first detection means at the tip of the document tray in order to prevent the transport roller from idling. For example, even a document with punch holes or the like at the tip of the document can be detected without any problem. .. Further, as the tray rises, the tip of the document is detected by the filler contact type second detection means provided before the transport roller, so that the idle rotation of the transport roller can be prevented. Further, in the filler used as the second detection means, since the tip of the document may be detected by raising the tray, it is not necessary to lengthen the tip of the document so as to come into contact with the tip of the document from the beginning, and it is possible to avoid an increase in the size of the device. That is, according to the present embodiment, it is possible to realize a configuration that is small in size and can detect a document at a predetermined position on the document tray with high accuracy.

The image forming apparatus 100 of the present embodiment that realizes this will be described. FIG. 1 is a schematic configuration diagram of the image forming apparatus 100 of the present embodiment.

[Image forming device]
As shown in this figure, the image forming apparatus 100 of the present embodiment includes an automatic document conveying device (hereinafter, simply referred to as a conveying device) 200, a paper feeding device 130, an image reading device 140, an image drawing device 150, and the like. An operation panel 160 on the outer surface of the image forming apparatus 100 and a control unit 300 (see FIGS. 3 and 4) are provided.

The transport device 200 includes a document tray section 210 and a transport section 230 having various rollers and the like. The transport device 200 transports the document placed on the document tray section 210 by the transport section 230 onto the slit glass 260 (see FIG. 2A), and the image reading device 140 completes reading through the slit glass 260. After passing the original document through the slit glass 260, the paper is ejected to the output tray 250 (see FIG. 2A). Further, the transport device 200 is movably attached to the image reading device 140 via an opening / closing mechanism (not shown).

The paper feed device 130 is a paper feed cassette 131, 132, 133 that stores recording papers of different sizes, and a movable paper feed table that can be raised and lowered in the paper feed cassettes 131, 132, 133, and is up and down with the base end as a fulcrum. A paper feeding means including a bottom plate serving as a paper tray that rotates in a direction and various rollers for transporting the recording paper P stored on the bottom plates in the paper feed cassettes 131, 132, 133 to the image forming position of the image forming apparatus 150. It is equipped with 134. The recording paper P stored in the selected paper cassette 131 is fed by the paper feeding means 134 and transported toward the transport path K. The recording paper P passes through the transport path K in which a plurality of transport rollers are arranged and reaches the resist roller pair 156 of the image forming apparatus 150 described later.

The image reader 140 includes a first carriage 141 equipped with a light source and a mirror member, a second carriage 142 equipped with a mirror member, an imaging lens, and an image pickup unit 143, and is an image on a document (original image). To read. The image reader 140 irradiates the document passing over the slit glass 260 with the light source mounted on the first carriage 141, and from the document by each mirror member mounted on the first carriage 141 and the second carriage 142. The reflected light of the above is folded back, and the reflected light is imaged by an imaging lens and read by the imaging unit 143.

The image forming apparatus 150 includes an exposure apparatus 151, a photoconductor drum 152, a developing apparatus 153, a transfer unit 154, a fixing device 155, a resist roller pair 156, a fixing roller 157, and a pressure roller 158. .. The image forming apparatus 150 exposes the photoconductor drum 152 by the exposure apparatus 151 that irradiates the exposure light L based on the original image read by the imaging unit to form a latent image on the photoconductor drum 152, and the developing apparatus 153. To the photoconductor drum 152, toners of different colors are supplied and developed. Then, the image forming apparatus 150 transfers the image developed on the photoconductor drum 152 by the transfer unit 154 to the recording paper supplied from the paper feeding device 130, and then transfers the toner image transferred to the recording paper by the fixing device 155. The toner is melted to fix the color image on the recording paper.

The operation panel 160 is a visual user interface for confirming the state of the image forming apparatus 100 and the operation mode set by the user, and is realized by a display device such as an LCD (Liquid Crystal Display). The operation panel 160 is also a user interface for the user to input the setting of the operation mode of the image forming apparatus 100. The operation panel 160 includes an input unit and a display unit, provides various information such as device information to the user, and accepts operations by various users such as operation settings and operation instructions. Further, in the present embodiment, if the document is not correctly set in the document tray unit 210, a warning to the user is displayed.

The image forming apparatus 100 may also include a warning lamp, a buzzer sound output device, and the like.

The control unit 300 controls the overall operation of the image forming apparatus 100. Details will be described later.

[Transporting device]
Next, the details of the transport device 200 will be described with reference to FIGS. 2 (a), 2 (b) and 2 (c). FIG. 2A is a cross-sectional view of a main part of the transport device 200 of the present embodiment. Further, FIG. 2B is an enlarged view of the document tray portion 210. Further, FIG. 2C is a schematic top view of the document tray portion 210.

As shown in this figure, the transport device 200 includes a document tray unit 210, a transport unit 230, a paper output tray 250, a slit glass 260, and a close contact image sensor (CIS) 270.

The document tray section 210 includes a document tray 201, an optical sensor 202, a filler 203, an upper cover 204, a tray drive device 205 (see FIGS. 3 and 4), and a side fence 207.

The document tray 201 is a movable table on which documents are placed and can be raised and lowered, and is a rotating plate that rotates in the vertical direction with the base end portion 206 as a fulcrum. As a result, the document tray 201 can adjust the front end portion of the document placed on the document tray 201 in the transport direction (hereinafter referred to as the document transport direction) to an appropriate height.

The optical sensor 202 is a sensor (first detection means) provided on the document tray 201. When the document is placed on the document tray 201, the optical sensor 202 outputs a detection signal. The detection signal output by the optical sensor 202 is used for processing in the control unit 300, which will be described later, and serves as a trigger for detecting that the document is placed on the document tray 201.

The optical sensor 202 is provided upstream of the pickup roller 231 which is a transport roller of the transport unit 230, which will be described later, in the document transport direction. In other words, the optical sensor 202 is provided closer to the base end 206 than the pickup roller 231. The position where the optical sensor 202 is provided corresponds to a position farther from the front end portion of the document tray 201 than the pickup roller 231.

The position of the optical sensor 202 is a position where a document placed in a position where the pickup roller 231 can transport the document downstream in the transport direction can be detected. Further, the position of the optical sensor 202 is provided at a position where the distance from the pickup roller 231 in the transport direction is shorter than the minimum length of the document (the document to be detected) that can be handled by the image reading device 140. For example, when the smallest document that can be handled is the size of a business card, even if the business card is placed on the document tray so that the direction of the short side of the business card is the transport direction, the optical sensor 202 is located at the position where the business card is detected. Is placed. However, the optical sensor 202 according to the present embodiment is in a position where even a document having punch holes or the like can be reliably detected. Therefore, the position where the optical sensor 202 is arranged corresponds to a distance longer than the distance between the punch hole and the pickup roller 231 in the document transport direction when the optical sensor 202 is placed in a state where it can be transported by the pickup roller 231 in the document transport direction. It is a position to do. Further, as shown in FIG. 2C, the optical sensor 202 is located within the long side of the size of the business card placed at the substantially center of the direction orthogonal to the document transport direction (hereinafter referred to as the width direction). ..

Since the optical sensor 202 is arranged as described above, in the present embodiment, the document placed on the document tray 201 can be detected with high accuracy. In particular, documents of various sizes can be detected with high accuracy.

The filler 203 includes a filler member and a set sensor. The filler member is a rod-shaped or plate-shaped member that is detected by contacting the tip of a document placed on the document tray 201. The filler member is rotatably attached to the upper cover 204 provided on the upper part of the document tray 201. Further, the filler member that comes into contact with the document is arranged downstream of the pickup roller 231 in the document transport direction. The set sensor is provided at a position facing the filler member of the document tray 201. When the document is placed on the document tray 201, the filler member rotates, and the tip portion of the filler member facing the set sensor is disengaged from the set sensor. As a result, the filler 203 functions as a second detection means for detecting the tip of the document on the downstream side in the document transport direction.

Further, as shown in FIG. 2C, the filler 203 is arranged outside the widthwise end portion of the pickup roller 231 in the width direction. However, it is arranged inside the edge in the width direction of the smallest document to be detected. Since the filler 203 can be arranged in this way, in the present embodiment, the peripheral configurations such as the upper cover 204 and the lower cover, the reverse roller 232, and the pull-out roller 233 on the downstream side in the transport direction of the filler 203 are arranged. It is small enough not to get in the way.

When the filler 203 detects the tip of the document, it outputs a detection signal to the control unit 300. In this embodiment, the filler 203 detects the tip of the document when the document tray 201 is raised. Therefore, the length of the filler member may be such that the original tray 201 can be touched and detected in a state of being raised to the uppermost end.

The tray drive device 205 is an elevating means for raising and lowering the document tray 201 according to an instruction from the control unit 300. In the present embodiment, for example, it is realized by a motor or the like, and the document tray 201 is rotated clockwise or counterclockwise with the base end portion 206 as a fulcrum. Details of the drive control of the tray drive device 205 will be described later.

Each side fence 207 is movable with a member that regulates the position of the document placed on the document tray 201 in the width direction, but only one of the side fences 207 may be movable. It is omitted in FIGS. 2 (a) and 2 (b).

The transport unit 230 transfers the document placed on the document tray 201 to the image reading unit 245 (between the slit glass 260 and the document holding member facing the slit glass 260) located between the reading inlet roller 235 and the first reading outlet roller 236. Transport toward. The transport unit 230 includes a transport roller which is a transport means, a paper detection means, and a roller drive device 249 (see FIGS. 3 and 4).

The transport rollers include a pickup roller 231, a reverse roller 232, a pull-out roller 233, a skew roller pair 239, an intermediate roller 234, a reading inlet roller 235, a first reading outlet roller 236, and a second reading outlet roller. 237 and a paper ejection roller 238 are provided.

Further, as the paper detecting means, for example, a bumping sensor 241 and 242, a reading inlet sensor 243, a resist sensor 244, and a paper ejection sensor 246 are provided.

In the transport unit 230, the pickup roller 231 transfers a document to the top-level document of the document bundle placed on the document tray 201, thereby feeding the document into the paper feed port. Then, the original document is conveyed by the reverse roller 232 arranged so as to face the pull-out roller 233 with the conveying path interposed therebetween. Here, the pull-out roller 233 rotates in the transport direction, and the reverse roller 232 rotates in the direction opposite to the transport direction. Further, the reverse roller 232 rotates in the opposite direction to the paper feed belt when the original is double-fed, but when the reverse roller 232 is in contact with the paper feed belt, or only one original is conveyed. If so, the torque limiter works to rotate the paper feed belt. A paper feed belt may be used instead of the pull-out roller 233.

The document is further aligned by the primary abutment according to the drive timing of the pull-out roller 233 and the pickup roller 231, and is pulled out and conveyed after the alignment. The pull-out roller 233 may be provided with a paper thickness measuring sensor for measuring the paper thickness.

The document pulled out and conveyed by the intermediate roller 234 is turned by being conveyed by the curved portion, and is conveyed to the vicinity of the slit glass 260 by the reading inlet roller 235 with the surface of the document facing downward.

The reading inlet roller 235 conveys the document conveyed to the vicinity of the slit glass 260 while contacting the slit glass 260, and the first reading outlet roller 236 further conveys the document after the scanning is completed, and the close contact image sensor 270. Pass through the reading surface. The second scanning outlet roller 237 transports the scanned document by the close contact image sensor 270 toward the paper ejection port. When double-sided scanning is not performed, the original is passed through without being scanned by the close contact image sensor 270.

The original document conveyed by the second reading outlet roller 237 is ejected to the paper ejection tray 250 by the paper ejection roller 238.

The abutting sensor 241 and 242, the reading inlet sensor 243, the resist sensor 244, and the paper ejection sensor 246 are provided along the transport path, respectively, and control the transport of the original, such as the transport distance and the transport speed. Used for.

Further, a document width sensor for detecting the document width may be provided between the pull-out roller 233 and the intermediate roller 234. The document width sensor is composed of, for example, a plurality of light receiving elements arranged in the width direction of the document, and detects the document width based on the light receiving result from the irradiation light provided at opposite positions across the transport path.

The roller drive device 249 drives each transfer roller according to an instruction from the control unit 300. The roller drive device 249 is realized by, for example, a motor or the like.

[Control unit]
The control unit 300 controls the operation of the image forming apparatus 100. In the present embodiment, for example, when the optical sensor 202 detects that the document is placed on the document tray 201, the optical sensor 202 controls the document tray 201 to be raised. Further, when the filler 203 detects the tip of the document, the pickup roller 231 is rotated to start the transfer of the document.

[Hardware configuration of control unit 300]
First, the hardware configuration of the control unit 300 will be described. FIG. 3 is an example of the hardware configuration of the control unit 300, and includes a configuration similar to that of a general information processing device. The control unit 300 according to the present embodiment includes a CPU (Central Processing Unit) 301, a RAM (Random Access Memory) 302 as a storage unit, a ROM (Read Only Memory) 303 as a storage unit, and an HDD as a storage unit. (Hard Disk Drive) 304 and I / F 305 as an interface are connected via a bus 309 as a communication means.

The CPU 301 is a calculation means and controls the entire operation of the image forming apparatus 100. The RAM 302 is a volatile storage medium capable of high-speed reading and writing of information, and is used as a work area when the CPU 301 processes information. The ROM 303 is a read-only non-volatile storage medium, and stores programs such as firmware. The HDD 304 is a non-volatile storage medium capable of reading and writing information, and stores an OS (Operating System), various control programs, application programs, and the like.

The I / F 305 connects and controls the bus 309 with various hardware, networks, and the like. In the present embodiment, the operation panel 160 and the dedicated device 308 are connected to the I / F 305.

The dedicated device 308 is hardware for realizing a function of performing a dedicated operation in the image forming apparatus 100. For example, in the present embodiment, the tray drive device 205, the roller drive device 249, the optical sensor 202, and the filler 203 are used. , Each hardware configuration such as various sensors in the transport unit 230.

The control unit 300 is a software control unit that realizes a predetermined function by reading a program stored in a ROM 303, an HDD 304, or the like into a RAM 302 and executing the program by the CPU 301 using each hardware configuration included in the dedicated device 308. To configure.

[Function block of control unit]
Next, among the functions realized by the CPU 301 executing the program in the control unit 300, the functions related to the present embodiment will be described. FIG. 4 is an example of a functional block diagram of the control unit 300 of the present embodiment. As shown in this figure, the control unit 300 includes a first detection unit 321, a second detection unit 322, a document tray drive unit 323, a transport roller drive unit 324, and a warning output unit 325.

When the first detection unit 321 receives the detection signal from the optical sensor 202, the first detection unit 321 outputs the reception signal to the document tray drive unit 323 and the second detection unit 322.

When the second detection unit 322 receives the detection signal from the filler 203 within a predetermined period after receiving the reception signal from the first detection unit 321, the second detection unit 322 outputs the reception signal to the transport roller drive unit 324. On the other hand, if the detection signal is not received from the filler 203 within a predetermined period, the non-received signal is output to the warning output unit 325 and the document tray drive unit 323.

When the document tray driving unit 323 receives the received signal from the first detection unit 321, the document tray driving unit 323 raises the document tray 201. Further, when the non-received signal is received, the document tray 201 is lowered. In the present embodiment, when a received signal is received, an ascending signal is output to the tray driving device 205, and when a non-received signal is received, a descending signal is output to the tray driving device 205. When the tray drive device 205 receives the rising signal, the tray driving device 205 rotates the document tray 201 in the direction in which the tip portion in the document transporting direction rises. On the other hand, when the descending signal is received, the tip portion is rotated in the descending direction.

When the transfer roller drive unit 324 receives the received signal from the first detection unit 321 and receives the received signal from the second detection unit 322, the transfer roller drive unit 324 drives the roller drive device 249 that rotates the transfer roller including the pickup roller 231.

When the warning output unit 325 receives the non-received signal from the second detection unit 322, the warning output unit 325 outputs a warning to the user. The warning output is, for example, a message indicating that the original is not set correctly is output to the operation panel 160, a warning lamp is turned on, a buzzer sound is output, and the like.

The first detection unit 321 may also output a received signal to the warning output unit 325. In this case, when the warning output unit 325 receives the received signal from the first detection unit 321, the warning output unit 325 outputs a predetermined output. The predetermined output is, for example, an output indicating that the original is set correctly, and may be displayed to that effect on the operation panel 160, or a sound may be output.

As a result, the user can know that the document has been correctly set in the document tray 201. On the contrary, if the user has set the document in the document tray 201 but there is no output indicating that the document has been set correctly, the user can take measures such as resetting the document.

[Original detection and transport processing]
Next, the flow of the document detection and transport processing in the transport device 200 of the present embodiment will be described. FIG. 5 is a processing flow of the document detection and transport processing of the present embodiment. Initially, as shown in FIG. 6A, it is assumed that the document tray 201 is arranged at the lowermost end.

The first detection unit 321 determines whether or not a detection signal has been received from the optical sensor 202 at predetermined time intervals (step S1101). Upon receiving the detection signal, the first detection unit 321 outputs the received signal to the document tray drive unit 323 and the second detection unit 322.

When the document tray driving unit 323 receives the received signal from the first detection unit 321, the document tray driving unit 323 raises the document tray 201 (step S1102). As a result, as shown in FIG. 6B, when the document is set at the correct position, the position of the tip of the document in the document transport direction is located downstream of the pickup roller 231 in the document transport direction.

At this time, as shown in FIG. 6B, when the original is placed in the correct position of the original tray 201, the filler 203 can detect the tip of the original. On the other hand, as shown in FIG. 6C, when the tip of the document is located upstream of the pickup roller 231 in the document transport direction, that is, when the pickup roller 231 is arranged at a position where it may idle. The filler 203 cannot detect the original.

Then, the second detection unit 322 determines whether or not the detection signal has been received from the filler 203 within a predetermined period after receiving the reception signal from the first detection unit 321 (step S1103). Then, when the second detection unit 322 receives the detection signal within a predetermined period, the second detection unit 322 outputs the reception signal to the transport roller drive unit 324. On the other hand, if it is not received, the second detection unit 322 outputs a non-reception signal to the warning output unit 325 and the document tray drive unit 323.

When the transport roller drive unit 324 receives the received signal from the second detection unit 322, the transport roller drive unit 324 performs transport control to drive the document transport unit (step S1104), and ends the process.

On the other hand, the warning output unit 325 that has received the non-received signal outputs a warning, and the document tray driving unit 323 lowers the document tray 201 (step S1105). Return to step S1101.

As described above, in the image forming apparatus 100 of the present embodiment, the document is set in the document tray 201 and the document is set in a position where it can be conveyed by the transfer roller (pickup roller 231). It is detected by an independent detection means. Specifically, the optical sensor 202 detects that the document has been set in the document tray 201, and the filler 203 detects that the document has been set in a position where it can be conveyed by the transfer roller.

As described above, in the present embodiment, since the detection is performed in two steps, it is possible to accurately detect whether the original is set at a position where it can be conveyed. Therefore, the possibility that the transport roller (pickup roller 231) is idle is reduced.

Further, the degree of freedom in the arrangement position of the optical sensor 202 arranged on the document tray 201 is increased. Therefore, for example, the optical sensor 202 can be arranged so as to avoid the positions of punch holes in the document. Moreover, even a small document can be placed in a detectable position.

Then, after the detection by the optical sensor 202, the document tray 201 is raised, and then the detection is performed by the filler 203. Therefore, the length of the filler 203 can be shortened. Therefore, the transport device 200 and the image forming device 100 provided with the transfer device 200 do not become large.

By urging the document tray 201 to the pickup roller 231 side with a spring or the like, the document regulating portion of the lower cover can be eliminated and the document tray 201 can be flattened. At this time, the original can be set by pulling it beyond the filler 203 to the vicinity where the reverse roller 232 and the pull-out roller 233 on the downstream side face each other. Then, the time for raising the document tray 201 after the detection by the optical sensor 202 can be omitted, and the document can be quickly transported by the transport roller based on the detection result of the optical sensor 202 and the filler 203.

As described above, according to the present embodiment, it is possible to accurately detect that a wide range of size documents are correctly detected regardless of the state of the document such as having or not punched holes. Therefore, the idle rotation of the transport roller can be reduced. In addition, the transport device 200 and the image forming device 100 are not enlarged.

<Modification 1>
In the above embodiment, the case where an optical sensor, which is a reflective sensor for non-contact detection by optical means, is used as the first detection means arranged on the document tray 201 has been described as an example. The first detection means is not limited to this. For example, as shown in FIG. 7A, the filler may be pushed in (filler contact type sensor 202a).

<Modification 2>
Further, in the above embodiment, the filler 203 is used to detect the tip of the document by raising the document tray 201, but the present invention is not limited to this. For example, optical sensors 203a and 203b (see FIGS. 7 (b) and 7 (c)) that are wide in the width direction on the surface of the document tray 201 may be used.

For example, as shown in FIG. 7B, the optical sensor 203a may be arranged at the tip of the document tray 201. Further, as shown in FIG. 7C, the optical sensor 203b may be arranged on the upper part of the document tray 201 (on the upper cover 204).

By using optical sensors 203a and 203b that are wide in the width direction, even an original with punched holes or the like can be detected.

<Modification 3>
Further, as shown in FIG. 8, in the case of the image forming apparatus 100 in which the paper feed device 130 or the manual feed tray 290 is provided with the transfer paper, the present embodiment may be applied to the paper feed device 130 or the manual feed tray 290. .. That is, the optical sensor 202 and the filler 203 may be provided in the same arrangement as in the above embodiment, and the paper feed (paper) at a predetermined position of the paper feed device 130 or the manual feed tray 290 may be detected.

100: Image forming device, 130: Feeding device, 131: Feeding cassette, 132: Feeding cassette, 133: Feeding cassette, 134: Feeding means, 140: Image reading device, 141: First carriage, 142: Second carriage, 143: image pickup unit, 150: image drawing device, 151: exposure device, 152: photoconductor drum, 153: development device, 154: transfer unit, 155: fixing device, 156: resist roller pair, 157: fixing Roller, 158: Pressurized roller, 160: Operation panel, 200: Conveyor, 201: Document tray, 202: Optical sensor, 202a: Filler contact type sensor, 203: Filler, 203a: Optical sensor, 203b: Optical sensor , 204: Top cover, 205: Tray drive, 206: Base end, 207: Side fence, 210: Document tray, 230: Transport, 231: Pickup roller, 232: Reverse roller, 233: Pullout roller, 234 : Intermediate roller, 235: Reading inlet roller, 236: First reading outlet roller, 237: Second reading outlet roller, 238: Paper ejection roller, 239: Skew roller pair, 241: Lump sensor, 242: Lump sensor, 243: Reading inlet sensor, 244: Resist sensor, 245: Image reader, 246: Paper ejection sensor, 249: Roller drive, 250: Paper ejection tray, 260: Slit glass, 270: Adhesion image sensor, 290: Manual feed tray ,
300: Control unit, 301: CPU, 302: RAM, 303: ROM, 304: HDD, 305: I / F, 308: Dedicated device, 309: Bus, 321: First detection unit, 322: Second detection unit, 323: Document tray drive unit, 324: Conveyor roller drive unit, 325: Warning output unit,
K: transport path, L: exposure light, P: recording paper

Japanese Unexamined Patent Publication No. 2008-30939

Claims (7)

A transport device including a paper tray on which paper is placed and a transport means for transporting the paper placed on the paper tray.
The paper tray has a first detection means for detecting that the paper is placed, and the transport device has the tip of the paper on the downstream side in the paper transport direction on the downstream side of the transport means. A transport device characterized by comprising a second detection means for detecting. The transport device according to claim 1.
The first detecting means is upstream of the transporting means in the paper transporting direction, and the distance from the transporting means is shorter than the length of the smallest paper to be detected in the paper transporting direction. Conveyor device. The transport device according to claim 1 or 2.
The paper tray can be raised and lowered.
The transport device further includes an elevating means for elevating and lowering the paper tray.
After the paper is detected by the first detecting means, the elevating means raises the paper tray to a position where it comes into contact with the conveying means.
The second detection means is a transport device characterized in that the paper tray is raised to detect the tip end. The transport device according to any one of claims 1 to 3.
The transport device, wherein the first detection means is either an optical sensor or a filler. The transport device according to any one of claims 1 to 4.
The second detecting means is a transport device characterized by being either a filler provided on the upper part of the paper tray, an optical sensor provided on the paper tray or the upper cover of the paper tray. An image reading device comprising a reading means for reading an image of paper conveyed by the conveying device according to any one of claims 1 to 5. The transport device according to any one of claims 1 to 5.
An image forming apparatus comprising: an image forming apparatus for forming an image.

Images