JP2006276340A - Image reading apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image reading apparatus the operability of which is satisfactory when a document is set on a document placing table. <P>SOLUTION: Inlets 8 and document detection sensors 9 are disposed at positions on the left and right sides and front sides of the upper face of a frame 7 supporting a contact glass 6, When a document detection sensor 9 detects that a document larger than the size of the contact glass 6 is placed on the document placing face and the tilt angle of a document pressing plate 2 is set to a predetermined range of angle θ(°) from 0°, negative pressure at the inlets 8 is produced in each inlet 8 by ducts 12 and a fan 13. Thus, the document is sucked toward the document placing surface. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention belongs to the technical field of image reading apparatuses, and particularly relates to a technique for improving workability when setting a document on a document table.

  For example, a copying machine has a document placing table constituted by a contact glass supported by a frame, and a document pressing plate for pressing a document on the document placing table against the contact glass. While the original placed on the glass is pressed against the original placement table by the original pressing plate, the image of the original is optically read through the contact glass.

  At that time, if the document to be copied is larger than the size of the document table, especially if it is large enough to protrude from the document table and hang down, contact the document with the document pressing plate. Until the sheet is pressed against the glass, the document placement state on the document placement table becomes unstable, and there is a risk that the document is displaced or the document is dropped downward.

  Therefore, to avoid this, the operator closes the document pressing plate with one hand while pressing the document against the contact glass with one hand, and immediately before the document pressing plate comes into close contact with the document placing table, Although the work of releasing the hand pressed against the contact glass is performed, this work is very troublesome and cannot be said to have good workability.

  In order to solve this problem, Japanese Patent Application Laid-Open No. H10-228561 has a long plate-like auxiliary plate whose one end is rotatably supported in the same plane as the surface of the document table, and is attached to a predetermined position of the document table. When the original is set, there is a structure in which the auxiliary plate is rotated so that one end of the auxiliary plate protrudes from the apparatus main body, or a flat auxiliary plate supported so as to be movable in parallel with the surface of the original table. A configuration is disclosed in which, when a large-size document is provided on a document placing table, the auxiliary plate is moved in parallel so that one end of the auxiliary plate protrudes laterally from the apparatus main body.

Further, in Patent Document 2 below, a plate-like pressing member that covers this surface is provided on the surface of the original pressing plate that can be in close contact with the contact glass, and through holes that penetrate the front and rear surfaces of the pressing member are provided on the entire surface. A structure in which a plurality of suction pumps are formed to suck air through the space formed between the document pressing plate and the pressing member and the through hole, and the document is sucked to the document pressing plate by the suction pump Is disclosed.
JP-A-6-230620 Japanese Patent Laid-Open No. 5-323474

  However, in the technique of the above-mentioned Patent Document 1, although the document misalignment and the possibility that the document will drop downward are reduced for a document of a certain size, the position of the document is still maintained for a very large document. Misalignment may occur. In addition, when the original is a curled large-size original, the troublesome work of fixing the original with the hand as described above is necessary, and there is room for improvement in terms of workability.

  Further, the technique of Patent Document 2 is provided with a mechanism for sucking a document on a document pressing plate, and there is no disclosure about a configuration in which a mechanism for sucking a document is provided on the document placing table side.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an image reading apparatus with good workability when setting a document on a document table.

  According to the first aspect of the present invention, a document placement surface on which a document is placed and a predetermined portion that is pivotally supported by a rotation shaft with respect to the apparatus main body are pivotally supported on the document placement surface. An image reading apparatus provided with a document pressing plate configured to be able to contact and separate from the document loading plate, further comprising suction means for sucking a document placed on the document placement surface toward the document placement surface. It is what.

  According to a second aspect of the present invention, in the image reading apparatus according to the first aspect of the present invention, a detection unit that detects the presence or absence of a document at a predetermined position on the document placement surface, and the presence of a document by the detection unit. And a first suction control unit that, when detected, causes the suction unit to perform a suction operation.

  According to a third aspect of the present invention, in the image reading apparatus according to the second aspect, the first suction control unit performs the suction until the document pressing plate is separated from the document placement surface by a predetermined distance. When the document pressing plate is separated from the document placement surface by a predetermined distance or more, the suction operation by the suction unit is released.

  According to a fourth aspect of the present invention, in the image reading apparatus according to any one of the first to third aspects, the input operation means for inputting an instruction to cause the suction means to perform a suction operation, and the input operation means. And a second suction control unit that causes the suction unit to perform a suction operation when an input is performed.

  According to a fifth aspect of the present invention, in the image reading device according to the fourth aspect, the input operation means includes a pressable foot pedal installed at a lower portion of the image reading device, and the foot pedal pressed. A switch that outputs a press signal indicating that to the second suction control means, and the second suction control means receives the press signal from the switch, and It is characterized by causing the means to perform a suction operation.

  According to a sixth aspect of the present invention, in the image reading apparatus according to any one of the first to fifth aspects, the suction unit includes an air intake duct, a fan, and an air inlet formed at a predetermined position on the document placement surface. A negative pressure is generated in the air inlet through the air intake duct by the operation of the fan, and the original placed on the original placement surface is sucked to the original placement surface side. It is characterized by.

  According to a seventh aspect of the present invention, in the image reading device according to the sixth aspect, the document placement surface includes a contact glass and a frame that supports the contact glass, and the intake air The mouth is provided at a portion of the frame body on the document placement surface.

  According to the first aspect of the present invention, the suction means for sucking the document placed on the document placement surface toward the document placement surface is provided. The document can be fixed on the document placement surface without performing an operation of pressing the document placement surface. Thereby, it is possible to improve the workability when setting the document on the document table.

  According to the second aspect of the present invention, when the presence of a document is detected at a predetermined position on the document placement surface, the suction operation is performed by the suction means. Thus, it is possible to realize a configuration to perform, and it is possible to further improve the workability when setting the document on the document table.

  According to the third aspect of the present invention, the suction operation by the suction means is performed until the document pressing plate is separated from the document placing surface by a predetermined distance, and the document pressing plate is separated from the document placing surface by a predetermined distance. Since the suction operation is canceled when the document is separated from the document, the lifting of the document that may occur when the document pressing plate is separated from the document placing surface can be prevented. When the document is separated from the document placement surface by a predetermined distance or more, the document can be easily taken out.

  According to the fourth aspect of the present invention, the input operation means for inputting an instruction to cause the suction means to perform the suction operation, and the input by the input operation means causes the suction means to perform the suction operation. Since the second suction control means is provided, the operator can arbitrarily determine the execution timing of the suction operation.

  According to the fifth aspect of the present invention, the input operation means includes a pressable foot pedal installed at a lower portion of the image reading device and a pressing signal indicating that when the foot pedal is pressed. Since it has a switch that outputs to the second suction control unit, it is possible to realize a configuration that arbitrarily determines the execution timing of the suction operation by the suction unit with a relatively simple configuration. It is possible to instruct the execution timing of the suction operation with no posture.

  According to a sixth aspect of the present invention, the suction means includes an intake duct, a fan, and an intake port formed at a predetermined position on the document placement surface, and the intake duct is formed by the operation of the fan. Since a negative pressure is generated at the air intake port through which the document placed on the document placement surface is sucked to the document placement surface side, the document placement is relatively simple. It is possible to realize a configuration in which the document placed on the placement surface is sucked to the document placement surface side.

  According to the seventh aspect of the present invention, the document placement surface is configured to include a contact glass and a frame body that supports the contact glass, and the intake port is the frame body of the document placement surface. Therefore, it is possible to avoid an increase in the size of the image reading apparatus as compared with a case where an air inlet is provided separately from the mounting table constituting the document mounting surface.

  Hereinafter, an embodiment of a copier as an example of an image processing apparatus according to the present invention will be described with reference to the drawings. FIG. 1 is an external view showing an external configuration of the copying machine according to the first embodiment, and FIG. 2 is a block diagram showing an electrical configuration of the copying machine according to this embodiment.

  The copying machine 1 is a casing having a substantially rectangular parallelepiped shape having a document pressing plate 2 pivotally supported at a rear part on the upper surface, and includes a document reading unit 3 that reads a document image and a document reading unit 3. An image forming unit 4 that forms a read document image on recording paper and an operation panel 5 for inputting an instruction to the copying machine 1 to perform a desired operation regarding the copying operation of the copying machine 1 are provided.

  The document reading unit 3 includes the document pressing plate 2, a contact glass 6 on which the document is placed, and an image sensor that is disposed so as to be movable along the contact glass 6 at a position facing the contact glass 6. And an optical system unit (not shown).

  The contact glass 6 is supported by a frame body 7 having a predetermined width, and the surface (upper surface) of the contact glass 6 and the upper surface of the frame body 7 are substantially flush, and the upper surface of the contact glass 6 and the upper surface of the frame body 7 A document is placed on the surface composed of Hereinafter, this surface is referred to as a document placement surface.

  An intake port 8 and a document detection sensor 9 are disposed at positions on the upper and lower sides of the frame 7 on the left and right sides and the front side of the contact glass 6, respectively. The air inlet 8 is an opening capable of sucking outside air, and is formed to suck a document placed on the document placement surface, as will be described later.

  In the present embodiment, the document detection sensor 9 is installed corresponding to the intake port 8 and detects the presence or absence of a document on the document placement surface. The document detection sensor 9 includes a pair of light projectors / receivers, and the light output from the light projector that always outputs light is reflected by the document when the document is placed on the document placement surface. Is received by the light receiver. At this time, the document detection sensor 9 (light receiver) outputs an ON signal indicating that the reflected light has been received to the control unit 18 described later.

  In order to distinguish between a case where an original is placed on the original placement surface and a case where the original pressing plate 2 is closed in close contact with the original placement surface, an original detection sensor on the original pressing plate 2. A member that absorbs light output from the projector of the document detection sensor 9 and a member that reflects light from the projector toward a direction different from that of the light receiver may be installed at a position opposite to the projector 9. The document detection sensor 9 is an example of detection means in the claims.

  A document pressing plate detection sensor 10 is disposed at an appropriate position on the upper surface of the frame body 7. The document pressing plate detection sensor 10 includes a button 21 that can be moved in and out of the document placement surface, and an on / off switch (not shown) connected to the button 21. FIG. 3 is a side view seen from the direction of arrow A in FIG. As shown in FIG. 3, the button 21 is pushed down by the document pressing plate 2 in the range where the inclination angle of the document pressing plate 2 with respect to the document placement surface is from 0 degree to a predetermined angle θ (°), and the on / off state is changed. When the switch is turned on and the inclination angle of the document pressing plate 2 with respect to the document placement surface exceeds the predetermined angle θ (°), the pressing of the button 21 by the document pressing plate 2 is released, and the on / off switch is turned off. It is configured. The document pressing plate detection sensor 10 outputs a signal (an on / off signal of an on / off switch) corresponding to the posture of the document pressing plate 2 to the control unit 18 described later.

  The image forming unit 4 forms an image on a recording sheet based on the image data read by the document reading unit 3, and is not shown in detail, but faces the photosensitive drum and the peripheral surface of the photosensitive drum. A charging unit disposed on the downstream side of the charging unit and facing the circumferential surface of the photosensitive drum, and a downstream side of the exposing unit facing the circumferential surface of the photosensitive drum. And a cleaning unit disposed downstream of the developing unit and facing the peripheral surface of the photosensitive drum.

  Although not shown, the operation panel 5 includes a liquid crystal display unit, a numeric keypad, a start button for instructing the start of copying, a function button for instructing execution of various functions installed in the copying machine 1, and the like. Although not shown in the drawings, the copying machine 1 includes a paper feed cassette that stores recording paper to be supplied to the image forming unit 4, and recording paper on which the recording paper on which an image is formed by the image forming unit 4 is discharged. It has a discharge part.

  In addition to the above configuration, the copying machine 1 of the present embodiment includes a document suction mechanism 11 including a duct 12 and a fan 13 in the apparatus main body 1A. The duct 12 is configured to communicate with each of the intake ports 8 and an unillustrated exhaust port formed at an appropriate position of the apparatus main body 1 </ b> A, and upstream of the fan 13 installed at a predetermined position in the duct 12. And an exhaust duct 15 on the downstream side of the fan 13. The intake duct 14 is provided corresponding to each intake port 8 and has a configuration in which each intake duct 14 communicates at a predetermined position, and the fan 13 is installed at this communicated position.

  In the document suction mechanism 11, air is sucked from the intake port 8 by the operation of the fan 13, and air is discharged from the exhaust duct 15 and the exhaust port. As a result, negative pressure is generated at the intake port 8. Suction and fix the original. The document suction mechanism 11 is an example of a suction unit in the claims.

  Further, the copying machine 1 of the present embodiment includes a suction instruction operation unit 16 for performing input for instructing the operation timing of the document suction mechanism 11. The suction instruction operation unit 16 includes a foot pedal 17 attached to a lower portion of the front surface of the housing, and a switch (not shown) that is turned on / off according to the posture of the foot pedal 17. Is depressed (pressed) with the foot, the switch is turned on, and an ON signal indicating that the foot pedal 17 has been depressed with the foot is output to the control unit 18 from the switch. The suction instruction operation unit 16 is an example of input operation means in the claims.

  The control unit 18 includes a CPU that executes arithmetic processing, a ROM that stores processing programs, data, and the like, and a microcomputer that includes RAM that temporarily stores data, and the recording set in the operation panel 5. Each operation in the document reading unit 3 and the image forming unit 4 is controlled based on image forming conditions such as paper size, magnification, density, and number of copies.

  Further, the control unit 18 functionally determines the document 19, the document pressing plate detection sensor 10, the document suction mechanism 11, and the suction instruction operation unit 16 to operate in association with each other. Have The determination unit 19 and the suction control unit 20 constitute first and second suction control means in the claims.

  The determination unit 19 determines whether or not a suction operation by the document suction mechanism 11 is necessary based on signals from the document detection sensor 9, the document pressing plate detection sensor 10, and the suction instruction operation unit 16. That is, the determination unit 19 outputs an ON signal indicating that the document is detected from the document detection sensor 9 and the inclination angle of the document pressing plate 2 from the document pressing plate detection sensor 10 is 0 degree with respect to the document placement surface. When an on signal indicating that the foot pedal 17 is depressed is output from the suction instruction operation unit 16, and when an on signal indicating that the foot pedal 17 is depressed is output. Then, it is determined that the suction operation by the document suction mechanism 11 is necessary.

  The suction control unit 20 operates the fan 13 of the document suction mechanism 11 when the determination unit 19 determines that the suction operation by the document suction mechanism 11 is necessary.

  A suction process by the control unit 18 of the copying machine 1 will be described. FIG. 4 is a flowchart showing a process of automatically setting the suction timing in the suction process.

  As shown in FIG. 4, the control unit 18 first determines whether or not the document pressing plate 2 is in the first state based on the detection signal of the document pressing plate detection sensor 10 (step # 1). This first state refers to a state in which the inclination angle of the document pressing plate 2 is in a range from 0 degree to a predetermined angle θ (°) with respect to the document placement surface. A state where the angle exceeds the predetermined angle θ (°) with respect to the document placement surface is referred to as a second state.

  As a result, when the document pressing plate 2 is not in the first state (in the second state) (NO in step # 1), the control unit 18 stands by while the document pressing plate 2 is in the first state. If it is in the state (YES in Step # 1), it is determined whether or not the document is placed on the document placement surface based on the detection signal of the document detection sensor 9 (Step # 2).

  The control unit 18 stands by when no document is placed on the document placement surface (NO in step # 2), while when the document is placed on the document placement surface ( YES at step # 2, and the fan 13 is operated to generate a negative pressure at the intake port 8 (step # 3). As a result, the document placed on the document placement surface is sucked to the document placement surface side by the negative pressure and fixed on the document placement surface.

  Next, the control unit 18 determines whether or not a copy operation instruction (copy instruction) has been issued (step # 4). If a copy operation instruction has not been issued (NO in step # 4). On the other hand, the process returns to the process of step # 1, while if a copy operation instruction is issued (YES in step # 4), the copy operation is executed, and then the document pressing plate 2 based on the detection signal of the document pressing plate detection sensor 10. Is determined to be in the second state (step # 5).

  As a result, when the document pressing plate 2 is not in the second state (the first state) (NO in step # 5), the control unit 18 continues to operate the fan 13 while the document pressing plate 2 Is in the second state (YES in step # 5), the operation of the fan 13 is stopped (step # 6).

  Thus, when the document pressing plate 2 is opened (taken from the first state to the second state) in order to take out the document from the document placing surface, the document is placed on the document as the document pressing plate 2 moves. It is possible to prevent the document from being lifted from the surface and falling downward or making it difficult to remove the document.

  Next, processing for manually setting the suction timing among the suction processing by the control unit 18 of the copying machine 1 will be described. FIG. 5 is a flowchart showing this process.

  When the foot pedal 17 is pressed (YES in step # 11), the control unit 18 operates the fan 13 to generate a negative pressure at the intake port 8 (step # 12). Thereafter, the control unit 18 determines whether or not the foot pedal 17 is released (step # 13). If the foot pedal 17 is not released (NO in step # 13), step # 13 is performed. Returning to step 12, the fan 13 is continuously operated. On the other hand, when the foot pedal 17 is released (YES in step # 13), the operation of the fan 13 is stopped (step # 14).

  As described above, when a document exceeding the size of the contact glass 6 is placed on the document placement surface, when the document pressing plate 2 is changed from the second state to the first state, the document is regarded as a document. Since the suction is automatically performed on the placement surface side, it is not necessary to manually press the document onto the document placement surface when the document pressing plate 2 is closed. Thereby, the workability at the time of setting a document on the document table can be improved. This is particularly effective in the case of a document having a large size such that the document protrudes from the document placement surface and hangs downward.

  Further, when the original is removed from the original placement surface after the original is copied, the original suction operation is continued until the original pressing plate 2 is changed from the first position to the second position. Therefore, it is possible to prevent the original from being lifted from the original placement surface with the movement of the original pressing plate 2, and dropping the original downward or making it difficult to take out the original. When the document pressing plate 2 is changed from the first position to the second position, the document suction operation is released (stopped), so that the document can be easily taken out.

  Further, since the suction instruction operation unit 16 for inputting an instruction for instructing the operation timing of the document suction mechanism 11 is provided, the document suction operation to the document placement surface side can be performed at a desired timing. The workability when setting a document on the mounting table can be further improved. Further, since the document suction mechanism 11 includes the foot pedal 17 and the switch, it is possible to realize a configuration that arbitrarily determines the execution timing of the document suction operation with a relatively simple configuration.

  In particular, since the foot pedal 17 configured to be stepped on with a foot is used as the input member for instructing the operation timing of the document suction mechanism 11, the execution timing of the suction operation can be instructed with a reasonable posture. Further, since the document suction mechanism 11 includes the air intake duct 12 and the fan 13, a configuration in which the document placed on the document placement surface is sucked to the document placement surface side with a relatively simple configuration. can do.

  Further, since the intake port 8 is installed in the frame body 7 that supports the contact glass 6, it is possible to avoid an increase in the size of the copying machine 1 as compared with a configuration in which a member having an intake port is provided separately from the frame body 7. Can be suppressed.

  In addition to the said embodiment, it can replace with the said embodiment and the deformation | transformation form demonstrated to the following form [1]-[4] is also employable for this invention.

  [1] Instead of the foot pedal 17, another operation member may be used. For example, you may make it arrange | position the button which has a function substantially equivalent to a foot pedal in the vicinity of an operation panel or this operation panel.

  [2] In the above embodiment, when the foot pedal 17 is depressed, the operation of the fan 13 is turned on. However, the foot pedal 17 is depressed and the document pressing plate 2 is changed from the second state to the first state. The operation of the fan 13 may be turned on when the setting is made. In the above embodiment, when the foot pedal 17 is stepped on, the original is sucked with a constant suction force. However, the present invention is not limited to this, and the magnitude of the suction force is adjusted according to the stepping amount of the foot pedal 17. You may comprise.

  [3] In the first embodiment, the air inlets 8 are installed at the left and right sides and the front side of the contact glass 6. However, the number and positions of the air inlets 8 can be changed as appropriate. . Further, the device for generating the negative pressure at the intake port 8 is not limited to the fan 13 described above, and may be a pump or the like. Further, when a plurality of intake ports 8 are installed, a configuration may be adopted in which a negative pressure is generated for each intake port 8. Further, in this case, when the intake port 8 and the document detection sensor 9 are installed in correspondence with each other, a portion of the document protruding from the contact glass 6 is detected by the document detection sensor 9 corresponding to that portion, and the document detection is performed. The suction force may be generated only at the intake port 8 corresponding to the sensor 9.

  [4] The present invention is not limited to a copying machine, but can be applied to any apparatus having a mechanism for reading a document image such as a scanner.

1 is an external view showing an external configuration of a copying machine as an example of an image reading apparatus according to the present invention. 2 is a block diagram showing an electrical configuration of a copying machine. FIG. It is the side view seen from the direction of arrow A of FIG. 6 is a flowchart showing a process of automatically setting the suction timing among the suction processes performed by the control unit of the copying machine. 6 is a flowchart showing processing for manually setting the suction timing in the suction processing by the control unit of the copying machine.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Copy machine 2 Original press plate 3 Original reading part 6 Contact glass 7 Frame body 8 Inlet 9 Original detection sensor 10 Original press plate detection sensor 11 Original suction mechanism 12 Duct 13 Fan 16 Suction instruction operation part 17 Foot pedal 18 Control part 19 Determination unit 20 Suction control unit

Claims (7)

A document placement surface on which a document is placed and a predetermined portion of the apparatus main body are pivotally supported by a pivot shaft so as to be able to contact and separate from the document placement surface. In an image reading apparatus provided with a manuscript pressing plate,
An image reading apparatus comprising: suction means for sucking a document placed on a document placement surface toward the document placement surface. Detecting means for detecting the presence or absence of a document at a predetermined position on the document placement surface;
The image reading apparatus according to claim 1, further comprising: a first suction control unit that causes the suction unit to perform a suction operation when the detection unit detects the presence of a document.   The first suction control unit causes the suction unit to perform a suction operation until the document pressing plate is separated from the document placement surface by a predetermined distance, and the document pressing plate is moved from the document placement surface to a predetermined value. The image reading apparatus according to claim 2, wherein the suction operation by the suction unit is canceled when the distance is greater than the distance. Input operation means for inputting an instruction to cause the suction means to perform a suction operation;
The image reading apparatus according to claim 1, further comprising a second suction control unit that causes the suction unit to perform a suction operation when an input is performed by the input operation unit.   The input operation means includes a pressable foot pedal installed at a lower portion of the image reading device, and a switch that outputs a press signal indicating the fact to the second suction control means when the foot pedal is pressed. 5. The image reading according to claim 4, wherein the second suction control unit causes the suction unit to perform a suction operation when the pressing signal is output from the switch. apparatus.   The suction means includes an intake duct, a fan, and an intake port formed at a predetermined position on the document placement surface, and generates negative pressure at the intake port through the intake duct by the operation of the fan. The image reading apparatus according to claim 1, wherein the document placed on the document placement surface is sucked toward the document placement surface.   The document placement surface is configured to include a contact glass and a frame body that supports the contact glass, and the intake port is installed in the frame body portion of the document placement surface. The image reading apparatus according to claim 6, wherein the image reading apparatus is an image reading apparatus.

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