JP2013195285A - Image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technique capable of preventing erroneous detection due to a single electromagnetic wave noise in detecting the presence or absence of a user operation for an operation part of an image forming apparatus.SOLUTION: An image forming apparatus 10 comprises: an operation part 6 (such as a touch panel 25); approach detection sensors 21 (21a to 21d); a noise detection sensor 27; and a determination part. The approach detection sensors detect approach of fingers of a user to the operation part 6. In addition, the noise detection sensor 27 detects the electromagnetic wave noise from the image forming apparatus. Meanwhile, the noise detection sensor 27 does not detect approach of fingers of a user to the operation part 6 by providing a shielding member 24 or the like. The determination part determines that a user operation to the operation part 6 is performed under such conditions that an approach detection signal by the approach detection sensors 21 is acquired and a noise detection signal by the noise detection sensor 27 is not acquired.

Description

  The present invention relates to an image forming apparatus such as an MFP (Multi-Functional Peripheral).

  Power saving is promoted in image forming apparatuses such as MFPs. For example, when print output or the like is not performed for a certain period, the image forming apparatus is shifted to a sleep mode or the like.

JP 2011-47779 A

  By the way, in order to further promote power saving in the sleep mode, for example, a technique for not only turning off the touch panel of the operation panel unit but also stopping the power supply to the display control chip of the touch panel in the sleep mode can be considered. More specifically, a proximity sensor that requires relatively low power consumption is arranged in the vicinity of the touch panel, and the proximity sensor indicates that the user's finger has approached the touch panel during sleep mode (not the touch panel in which power supply is stopped). To detect. In response to the approach detection signal, the image forming apparatus is returned from the sleep mode to the normal mode.

  However, in such a technique, a single electromagnetic noise (particularly a single electromagnetic noise) generated from an image forming apparatus or the like is mixed into the proximity sensor, and erroneous detection may occur due to the electromagnetic noise.

  The technique described in Patent Document 1 is a technique for suppressing the influence of stationary noise. Therefore, it is difficult for the technique described in Patent Document 1 to suppress the influence of a single (sudden) noise.

  Accordingly, an object of the present invention is to provide a technique capable of suppressing erroneous detection caused by a single electromagnetic wave noise when detecting the presence / absence of a user operation on an operation unit of an image forming apparatus.

  In order to solve the above-mentioned problem, the invention of claim 1 is an image forming apparatus, comprising: an operation unit; an approach detection sensor that detects an approach of a user's finger to the operation unit; and a user's finger to the operation unit. A noise detection sensor that detects electromagnetic wave noise from the image forming apparatus without detecting an approach, and a determination unit that determines whether or not a user operation has been performed on the operation unit, wherein the determination unit includes the proximity detection sensor It is characterized in that it is determined that a user operation has been performed on the operation unit on the condition that a noise detection signal from the noise detection sensor is not acquired in addition to an approach detection signal being acquired.

  According to a second aspect of the present invention, in the image forming apparatus according to the first aspect of the present invention, the influence of the user operation on the operation unit on the noise detection sensor is arranged between the proximity detection sensor and the noise detection sensor. It further comprises an electromagnetic shielding member to be suppressed.

  According to a third aspect of the present invention, in the image forming apparatus according to the first aspect of the present invention, the influence of the user operation on the operation unit on the noise detection sensor is arranged between the proximity detection sensor and the noise detection sensor. It further comprises an electromagnetic wave absorbing member to be reduced.

  According to a fourth aspect of the present invention, in the image forming apparatus according to any one of the first to third aspects, the noise detection sensor is provided closer to the main body of the image forming apparatus than the proximity detection sensor. It is characterized by that.

  According to a fifth aspect of the present invention, in the image forming apparatus according to the second or third aspect of the present invention, the operation unit has an operation panel unit, and the proximity detection sensor is on a front side of the operation panel unit. The noise detection sensor is provided on the back side of the operation panel unit.

  According to a sixth aspect of the present invention, in the image forming apparatus according to the fifth aspect of the invention, the operation unit includes an operation panel unit, and the proximity detection sensor is provided on a front side of the operation panel unit. The noise detection sensor is provided in a loop shape on the back side of the operation panel unit.

  According to a seventh aspect of the present invention, in the image forming apparatus according to the fifth aspect of the invention, the operation unit includes an operation panel unit, and the proximity detection sensor is provided on a front side of the operation panel unit. The noise detection sensor is linearly provided on the back side of the operation panel unit.

  According to an eighth aspect of the present invention, in the image forming apparatus according to the fifth aspect of the invention, the operation unit has a detachable operation panel unit, and the proximity detection sensor is located on a front side of the operation panel unit. The noise detection sensor is disposed away from an outer edge portion of the operation panel unit at a central portion on the back side of the operation panel unit, and the sensitivity of the noise detection sensor is determined by the noise detection sensor. It is reduced to such an extent that it does not react to a user operation from the front side with respect to the outer edge portion of the operation panel portion.

  According to a ninth aspect of the present invention, in the image forming apparatus according to the first aspect of the invention, the operation section includes a detachable operation panel section that can be attached to and detached from a main body of the image forming apparatus. The detection sensor is provided in the operation panel unit, and the noise detection sensor is provided on the main body side of the image forming apparatus, and the noise detection sensor and the operation panel unit are provided on the main body side of the image forming apparatus. An electromagnetic shielding member or an electromagnetic wave absorbing member is disposed between the two.

  According to a tenth aspect of the present invention, in the image forming apparatus according to the first aspect of the present invention, the image forming apparatus further includes an adjusting unit that adjusts the sensitivity of the noise detection sensor, and the operation unit is attached to and detached from the main body of the image forming apparatus. A detachable operation panel unit, wherein the proximity detection sensor is provided in the operation panel unit, and the noise detection sensor is provided on a main body side of the image forming apparatus, The adjustment unit is configured so that the noise detection sensor performs the adjustment when a user operation for adjustment, which is a test user operation on the operation unit, is performed in a state where the operation panel unit is detached from the main body of the image forming apparatus. It is characterized in that the sensitivity of the noise detection sensor is reduced until no response is made to a user operation.

  According to an eleventh aspect of the present invention, in the image forming apparatus according to any one of the first to tenth aspects, the proximity detection sensor and the noise detection sensor are proximity sensors of the same type.

  A twelfth aspect of the present invention is the image forming apparatus according to any one of the first to eleventh aspects, wherein the proximity detection sensor is provided around the touch panel on the front side of the operation panel portion of the operation portion. It is characterized by being.

  According to a thirteenth aspect of the present invention, in the image forming apparatus according to any one of the first to twelfth aspects, when it is determined that a user operation has been performed on the operation unit, the image forming apparatus is placed in a power saving mode. It is further characterized by further comprising state control means for returning from the state.

  According to the first to thirteenth aspects of the present invention, the user with respect to the operation unit is also provided that the proximity detection signal from the proximity detection sensor is acquired and the noise detection signal from the noise detection sensor is not acquired. It is determined that an operation has been performed. In other words, when single electromagnetic wave noise is detected by the noise detection sensor, it is not determined that a user operation on the operation unit has been performed. Therefore, it is possible to suppress erroneous detection caused by a single electromagnetic wave noise.

1 is a diagram illustrating an image forming apparatus (MFP). It is a figure which shows the functional block of an image forming apparatus. It is a front view of an operation panel part. It is a rear view of an operation panel part. It is a side view of an operation panel part. FIG. 4 is a side view of a state where an operation panel unit is attached to an MFP. It is a figure which shows the connection state of a proximity detection sensor signal etc. and IC chip. It is a figure which shows the basic principle regarding user operation detection (at the time of noise generation). It is a figure which shows the basic principle regarding user operation detection (when no noise occurs). It is a rear view of an operation panel part (2nd Embodiment). It is a side view of an operation panel part. It is a rear view of an operation panel part (3rd Embodiment). It is a side view of an operation panel part. It is a top view of an operation panel part. FIG. 9 is a view showing the vicinity of an operation panel unit of an image forming apparatus (third embodiment). FIG. 10 is a view showing the vicinity of an operation panel unit of an image forming apparatus (fourth embodiment). FIG. 10 is a view showing the vicinity of an operation panel unit of an image forming apparatus (fifth embodiment). It is a figure which shows the functional block of an image forming apparatus. It is a flowchart which shows the adjustment operation of the sensitivity of a noise detection sensor.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

<1. First Embodiment>
<1-1. Outline of configuration>
FIG. 1 is a diagram illustrating an image forming apparatus 10 (also referred to as 10A) according to the first embodiment. FIG. 2 is a diagram showing functional blocks of the image forming apparatus 10. Here, an MFP (Multi-Functional Peripheral) is exemplified as the image forming apparatus 10. In FIG. 2, functional blocks of the MFP 10 are shown.

  The MFP 10 is a device (also referred to as a multi-function device) having a scan function, a copy function, a facsimile function, a box storage function, and the like. Specifically, as shown in the functional block diagram of FIG. 2, the MFP 10 includes an image reading unit 2, a print output unit 3, a communication unit 4, a storage unit 5, an operation unit 6, and a controller 9. Various functions are realized by operating these components in a complex manner.

  The image reading unit 2 optically reads (that is, scans) a document placed at a predetermined position of the MFP 10 and generates image data of the document (also referred to as a scanned image). It is. The image reading unit 2 is also referred to as a scanning unit.

  The print output unit 3 is an output unit that prints out an image on various media such as paper based on data related to a print target.

  The communication unit 4 is a processing unit capable of performing facsimile communication via a public line or the like. Further, the communication unit 4 can perform network communication via the network NW. In this network communication, for example, various protocols such as TCP / IP (Transmission Control Protocol / Internet Protocol) are used. By using the network communication, the MFP 10 can exchange various data with a desired partner (for example, a computer).

  The storage unit 5 includes a storage device such as a hard disk drive (HDD). The storage unit 5 stores data related to the print job.

  The operation unit 6 includes an operation input unit 6a that receives an operation input to the MFP 10 and a display unit 6b that displays and outputs various types of information. The MFP 10 (specifically, its operation panel unit 20 (FIG. 1)) is provided with a touch panel (also referred to as a touch screen) 25 (FIG. 1) configured by embedding a piezoelectric sensor or the like in a liquid crystal display panel. . The touch panel 25 functions as a part of the operation input unit 6a and also functions as a part of the display unit 6b.

  The controller 9 is a control device that is built in the MFP 10 and controls the MFP 10 in an integrated manner. The controller 9 is configured as a computer system including a CPU and various semiconductor memories (RAM and ROM). The controller 9 implements various processing units by executing a predetermined software program (hereinafter also simply referred to as a program) PG1 stored in a ROM (for example, EEPROM) in the CPU. The program (specifically, a program module group) PG1 may be installed in the MFP 10 via a portable recording medium such as a USB memory, or a network NW.

  Specifically, as shown in FIG. 2, the controller 9 implements various processing units including a communication control unit 11, a display control unit 15, a determination unit 17, and a state control unit 19 by executing a program PG1. .

  The communication control unit 11 is a processing unit that controls communication operations between the MFP 10 and other devices.

  The display control unit 15 is a processing unit that controls display contents on the touch panel 25 or the like of the MFP 10. The display control unit 15 controls the operation of the touch panel 25 in cooperation with a control chip (a CPU or the like different from the controller 9) 28 (see FIG. 7) that controls display on the touch panel 25. Note that, in the sleep mode of the MFP 10, power supply to the part including the touch panel 25 and the control chip 28 is stopped, and power consumption is reduced. When the MFP 10 returns from the sleep mode to the normal mode, power supply to the control chip 28, the touch panel 25, and the like is resumed.

  The determination unit 17 is a processing unit that determines the presence / absence of a user operation on the operation unit 6 (specifically, the operation panel unit 20) based on detection signals from the proximity detection sensors 21 and the noise detection sensor 27.

  The state control unit 19 is a processing unit that controls the state (operation mode) of the MFP 10. The state control unit 19 controls switching operations related to a plurality of operation modes including a normal mode and a power saving mode (also referred to as a sleep mode). For example, when the determination unit 17 determines that a user operation has been performed on the operation unit 6, the state control unit 19 returns the MFP 10 from the power saving mode to the normal mode.

  As described above, the MFP 10 includes the operation panel unit 20, and the operation panel unit 20 includes the touch panel 25 on the front side thereof (see FIG. 3). The touch panel 25 is disposed near the center of the operation panel unit 20. FIG. 3 is a front view of the operation panel unit 20. FIG. 4 is a rear view of the operation panel unit 20, and FIG. 5 is a side view of the operation panel unit 20. FIG. 6 is a side view (partially sectional view) showing a state where the operation panel unit 20 is attached to the MFP 10.

  As shown in FIG. 3, on the front side of the operation panel unit 20, an approach detection sensor 21 (specifically, an antenna unit thereof) is provided so as to surround the outer peripheral edge of the substantially rectangular touch panel 25. The proximity detection sensor 21 is a proximity sensor that detects the approach of the user's finger to the operation unit 6 (specifically, the touch panel 25). Here, four approach detection sensors 21 are provided. Specifically, the proximity detection sensor 21a is provided on the upper side of the touch panel 25, the proximity detection sensor 21b is provided on the lower side of the touch panel 25, the proximity detection sensor 21c is provided on the left side of the touch panel 25, and on the right side of the touch panel 25. An approach detection sensor 21d is provided.

  The proximity detection sensor 21 also detects electromagnetic noise as will be described later.

  As shown in FIG. 4, a noise detection sensor 27 (specifically, an antenna portion thereof) is provided on the back side of the operation panel portion 20. Specifically, a linear noise detection sensor 27 is extended in the horizontal direction at a substantially central portion on the back side of the operation panel unit 20.

  The noise detection sensor 27 is a sensor that detects electromagnetic wave noise from the MFP 10. Here, the noise detection sensor 27 is configured as a proximity sensor of the same type as the proximity detection sensor 21.

  As each of the sensors 21 and 27, for example, a capacitive proximity sensor or an electromagnetic induction proximity sensor is used. The noise detection sensor 27 is preferably the same type (same type) sensor as the proximity detection sensor 21 in order to easily detect the same electromagnetic noise as the electromagnetic wave noise erroneously detected by the proximity detection sensor 21.

  The noise detection sensor 27 is configured not to detect the approach of the user's finger to the operation unit 6. Specifically, in this embodiment, as described below, by providing the shielding member 24 (electromagnetic shielding member), the noise detection sensor 27 performs the approaching operation even when the user's finger approaches the operation unit 6. Configured not to detect.

  As shown in FIG. 5 and the like, the operation panel unit 20 includes a plate-shaped shielding member 24 (24A) therein. The shielding member 24 is disposed on the back side of the touch panel 25 provided on the front side of the operation panel unit 20.

  The shielding member 24 is formed of a metal plate or the like, and is provided as a shield member (electromagnetic shield member). The shielding member 24 is a member that suppresses the influence of the user operation on the operation unit 6 on the noise detection sensor 27. Specifically, the shielding member 24 is provided so that the noise detection sensor 27 does not detect a change in capacitance (change in electromagnetic field) caused by a user operation on the touch panel 25. The shielding member 24 is disposed between the approach detection sensor 21 and the noise detection sensor 27. In other words, the noise detection sensor 27 is disposed on the opposite side of the proximity detection sensor 21 with the shielding member 24 interposed therebetween. The noise detection sensor 27 is electromagnetically shielded by the shielding member 24 so as not to detect the approach of the user's finger from the front side.

  The noise detection sensor 27 is provided at a position closer to the main body 30 of the MFP 10 than the proximity detection sensor 21. Thereby, electromagnetic wave noise from the MFP 10 side is detected better than the proximity detection sensor 21.

  Further, as shown in FIG. 6, an arm portion 33 is provided on the front side of the MFP 10. The arm portion 33 is provided so as to protrude further from the main body portion 30 of the MFP 10 to the front side (left side in the drawing). The operation panel unit 20 is held at the front end of the arm unit 33 at a predetermined angle. The operation panel unit 20 is held so as to be rotatable about a horizontal axis, and the holding angle of the operation panel unit 20 can be changed. As described above, the operation panel unit 20 is fixed (held) to the MFP 10 main body 30 so as to be rotatable, and is also expressed as a fixed operation panel unit 20.

  Here, an example in which the proximity detection sensor 21 and the noise detection sensor 27 are provided so as to protrude from the surface of the operation panel unit 20 is illustrated, but the present invention is not limited thereto. For example, the proximity detection sensor 21 and the noise detection sensor 27 may be embedded in the vicinity of the surface of the operation panel unit 20 so as not to protrude from the surface of the operation panel unit 20.

  By the way, it is also possible to determine that a user operation has been detected only by detecting signals exceeding the threshold value by the proximity detection sensors 21a to 21d in the sleep mode, and to perform a return operation from the sleep mode to the normal mode. It is. Such a technique is referred to as a “comparative example”.

  However, the proximity detection sensors 21a to 21d may detect electromagnetic noise. Examples of such noise include noise generated in a motor and a light emitting unit in the MFP 10. Specifically, noise generated in driving various motors, more specifically, noise associated with generation of an inrush current at the start of motor driving (or when the load fluctuates) is exemplified. Even in the sleep mode, the MFP 10 accepts print output data from another computer or the like connected via a network (such as a LAN), resumes power supply to only a required part such as the print output unit 3 and prints. It is possible to output (also referred to as sleep print). Thus, noise may occur even in the sleep mode.

  Therefore, in the above comparative example, if it is determined that the user operation is detected only by detecting signals that are equal to or higher than the threshold value by the proximity detection sensors 21a to 21d, electromagnetic wave noise may be erroneously detected as the user operation. . That is, when the movement of the user's finger is detected only by the proximity detection sensor 21, there is a possibility that a false detection due to noise (electromagnetic wave noise) generated in the vicinity of the MFP 10 may be performed.

  Therefore, in this embodiment, the presence or absence of a user operation on the operation unit 6 using not only the proximity detection sensor 21 but also the noise detection sensor 27 (specifically, an operation in which the user's finger approaches the operation unit 6). The mode which determines presence / absence) is illustrated.

  FIG. 8 and FIG. 9 are diagrams illustrating the basic principle regarding user operation detection. The upper part of each figure shows the output signal of the approach detection sensor 21 (specifically, any one of the approach detection sensors 21a to 21d), and the lower part of each figure shows the output signal of the noise detection sensor 27. ing. FIG. 8 shows each signal when electromagnetic noise (machine noise) from the MFP 10 is generated, and FIG. 9 shows each signal when electromagnetic noise from the MFP 10 is not generated. It is shown.

  Specifically, as described above, the determination unit 17 of the MFP 10 detects the approach of the user's finger within the certain period (minute period) Δt by the proximity detection sensor 21 and detects the electromagnetic wave noise by the noise detection sensor 27. When the device is detected (see FIG. 8), it is determined that there is no user operation on the operation unit 6. In other words, when both the approach detection signal from the approach detection sensor 21 and the noise detection signal from the noise detection sensor 27 are acquired (see FIG. 8), it is determined that there is no user operation on the operation unit 6. Here, it is determined that the approach of the user's finger is detected (in other words, the approach detection signal is detected) when the signal intensity by the approach detection sensor 21 is larger than the predetermined threshold value TH1. To do. Similarly, it is determined that electromagnetic wave noise is detected (in other words, a noise detection signal is detected) when the signal intensity by the noise detection sensor 27 is larger than the predetermined threshold value TH2.

  On the other hand, when an approach of the user's finger is detected by the proximity detection sensor 21 and no electromagnetic wave noise is detected by the noise detection sensor 27 within a certain period Δt (see FIG. 9), a user operation on the operation unit 6 is performed. It is determined. In other words, when the approach detection signal by the approach detection sensor 21 is acquired and the noise detection signal by the noise detection sensor 27 is not acquired (see FIG. 9), the determination unit 17 performs a user operation on the operation unit 6. Determine that it has been done.

  As described above, when the noise detection signal is acquired (detected) by the noise detection sensor 27, it is determined that there is no user operation on the operation unit 6. Therefore, it is possible to avoid erroneous detection (false determination) caused by a single electromagnetic wave noise, compared to the case where the presence or absence of a user operation is determined only by the proximity detection sensors 21a to 21d.

  FIG. 7 is a diagram illustrating a state in which detection signals from the proximity detection sensors 21 a to 21 d and the noise detection sensor 27 are input to the determination IC chip 29.

  As shown in FIG. 7, in the sleep mode of the MFP 10, the controller 9 receives detection signals from the proximity detection sensors 21 a to 21 d and the noise detection sensor 27 via the determination IC chip 29. Here, it is assumed that the determination IC chip 29 has five input channels. Among these, the input channels CH1 to CH4 accept output signals from the proximity detection sensors 21a to 21d, respectively, and the input channel CH5 accepts an output signal from the noise detection sensor 27. The determination IC chip 29 outputs an interrupt signal to the controller 9 on condition that the received signal exceeds a predetermined threshold value. The determination IC chip 29 also outputs a detection channel number (a channel number where a signal exceeding a predetermined threshold is detected) to the controller 9. Further, the controller 9 (specifically, the determination unit 17) that has received the interrupt signal specifies a detection source channel based on the data signal from the determination IC chip 29.

  When the detection source channel is channel CH5 (when the detection source channel includes channel CH5), the controller 9 determines that noise detection by the noise detection sensor 27 has been performed. That is, even when the signal is detected by the proximity detection sensor 21, when the signal detection by the noise detection sensor 27 is also performed, it is determined that noise is detected, and the detection signal ( The user operation detection signal is determined to be invalid.

  On the other hand, when the channel CH5 is not included in the detection source channel (when the signal detection is performed only by the proximity detection sensor 21), the controller 9 determines that the signal detection by the proximity detection sensor 21 is normally performed. To do. That is, when a signal is detected by the proximity detection sensor 21 and no signal is detected by the noise detection sensor 27, it is determined that any of the proximity detection sensors 21 has detected a user operation, and the proximity detection sensor 21 is detected. The proximity detection signal (also referred to as user operation detection signal) is determined to be valid.

  When the controller 9 (determination unit 17) determines that the approach detection signal (user operation detection signal) is valid, the controller 9 returns the MFP 10 from the sleep mode to the normal mode. When it is determined that the user operation detection signal is invalid, the determination unit 17 does not perform a return operation from sleep, and the MFP 10 is maintained in the sleep mode.

  According to the operation described above, the user operation on the operation unit is performed on the condition that the proximity detection signal from the proximity detection sensor 21 is acquired and the noise detection signal from the noise detection sensor 27 is not acquired. It is determined. In other words, when a single electromagnetic wave noise is detected by the noise detection sensor 27, it is not determined that a user operation has been performed on the operation unit. Therefore, it is possible to suppress erroneous detection caused by a single electromagnetic wave noise.

<2. Second Embodiment>
The second embodiment is a modification of the first embodiment. Below, it demonstrates centering on difference with 1st Embodiment.

  In the first embodiment, the linear noise detection sensor 27 (also referred to as 27A) is illustrated, but in the second embodiment, a loop-shaped noise detection sensor 27 (also referred to as 27B) is provided. A mode is illustrated (refer FIG. 10 etc.).

  10 and 11 are diagrams showing the operation panel unit 20 (20B) of the MFP 10 (also referred to as 10B) according to the second embodiment. FIG. 10 is a rear view of the operation panel unit 20B, and FIG. 11 is a side view of the operation panel unit 20B.

  As shown in FIG. 10, a noise detection sensor 27B configured as a loop antenna is arranged on the back side of the operation panel unit 20B. By using the loop-shaped noise detection sensor 27B, it is possible to detect electromagnetic wave noise with a relatively high sensitivity as compared with the case where the noise detection sensor 27A configured as a linear antenna as in the first embodiment is used. Is possible. In particular, it is possible to detect electromagnetic wave noise in a relatively wide range on the back side of the operation panel unit 20B.

  The operation in the second embodiment is the same as that in the first embodiment.

<3. Third Embodiment>
The third embodiment is a modification of the first embodiment. Below, it demonstrates centering on difference with 1st Embodiment.

  In each of the above embodiments, the fixed operation panel unit 20 (20A, 20B) is illustrated, but in this third embodiment, the detachable operation panel unit 20 that can be attached to and detached from the main body of the MFP 10 is shown. (20C) is illustrated.

  12 to 14 are diagrams showing the operation panel unit 20 (20C) of the MFP 10 (also referred to as 10C) according to the third embodiment. 12 is a rear view of the operation panel unit 20C, FIG. 13 is a side view of the operation panel unit 20C, and FIG. 14 is a top view of the operation panel unit 20C.

  FIG. 15 is a side view of the vicinity of the operation panel unit 20C. FIG. 15 shows a state in which the operation panel unit 20 </ b> C is attached to the base unit 32 that holds the detachable operation panel unit 20. However, the operation panel unit 20 can be detached from the base unit 32.

  As shown in these drawings, a noise detection sensor 27C configured as a linear antenna is disposed on the back side of the operation panel unit 20C.

  The shielding member 24C is formed so as to cover the front surface side and the side surface side of the noise detection sensor 27C. Specifically, the shielding member 24C includes a planar portion 24p substantially parallel to the touch panel 25, and a protruding portion (a bent portion) that is bent at a substantially right angle from the parallel portion 24p toward the back side and protrudes to the back side. ) 24q (see FIG. 13).

  Here, it is noted that when the user starts an operation on the operation panel unit 20, the user's finger often approaches from the front side of the operation panel unit 20. The position, size, and sensitivity of the noise detection sensor 27 are adjusted so that the noise detection sensor 27 does not react when the user's finger approaches the operation panel unit 20 from the front side of the operation panel unit 20. . According to this, when the user approaches the operation panel unit 20 (particularly when the user approaches the operation panel unit 20 from the front side of the operation panel unit 20), the noise detection sensor 27 does not react in principle. Therefore, the noise detection sensor 27 can accurately detect noise.

  More specifically, the linear noise detection sensor 27 (27 </ b> C) is arranged at a central portion on the back side of the operation panel unit 20 so as to be separated from the outer edge portion of the operation panel unit 20. Specifically, the relatively short linear noise detection sensor 27 </ b> C is provided at a position that is offset from four upper, lower, left, and right edge portions of the substantially rectangular operation panel unit 20. It is arranged in a state where the upper, lower, left and right extended portions (access areas of the user's fingers) are left open. Further, the sensitivity of the noise detection sensor 27 is reduced (adjusted) to such an extent that the noise detection sensor 27 does not react to a user operation from the front side with respect to the outer edge portion of the operation panel unit 20.

  Here, as described above, the shielding member 24 </ b> C is formed so as to cover the front surface side and the side surface side of the noise detection sensor 27. Specifically, the shielding member 24C includes a flat portion 24p substantially parallel to the touch panel 25, and a protruding portion (a bent portion) that is bent at a substantially right angle from the flat portion 24p toward the back side and protrudes to the back side. ) 24q. Accordingly, in particular, the user tries to grasp the left end portion and the right end portion of the operation panel unit 20 in order to remove the operation panel unit 20 mounted on the MFP main body side member (arm unit 33) from the base unit 32. The noise detection sensor 27 does not react to the approaching operation even when the fingers are brought closer to the operation panel unit 20 from the front side of the unit 20.

  The noise detection sensor 27 (27C) can detect electromagnetic wave noise emitted from the MFP 10 satisfactorily as in the first embodiment. When the electromagnetic wave noise is detected by the proximity detection sensor 21, the electromagnetic wave noise can be detected by the noise detection sensor 27. Therefore, it is possible to appropriately detect a user operation on the operation panel unit 20 by performing the same operation as in the first embodiment.

<4. Fourth Embodiment>
The fourth embodiment is a modification of the third embodiment. Below, it demonstrates centering on difference with 3rd Embodiment.

  In the said 3rd Embodiment, the aspect by which the noise detection sensor 27 is arrange | positioned at 20 C of detachable operation panel parts is illustrated. In the fourth embodiment, the noise detection sensor 27 is not arranged on the detachable operation panel unit 20 (20D) but is arranged on the main body side (more specifically, the base unit 32) of the MFP 10. To do.

  FIG. 16 is a diagram illustrating a state where the operation panel unit 20 (20D) is removed from the MFP 10 (also referred to as 10D) according to the fourth embodiment.

  As shown in FIG. 16, the operation panel unit 20 (20D) according to the fourth embodiment is also detachable from the main body unit 30 of the MFP 10 similarly to the operation panel unit 20C. That is, the operation panel unit 20D is also a detachable operation panel unit.

  The proximity detection sensor 21 is provided in the operation panel unit 20 as in the above embodiments. On the other hand, the noise detection sensor 27 (27D) is not provided in the operation panel unit 20, and is a main body side member of the MFP 10 (specifically, the back side of the base unit 32 holding the detachable operation panel unit 20). Is provided. Further, the shielding member 24 (24D) is not provided in the operation panel unit 20, but is disposed on the main body side of the MFP 10. The shielding member 24 </ b> D is disposed between the noise detection sensor 27 and the operation panel unit 20 and suppresses the influence exerted on the noise detection sensor 27 by a user operation on the operation panel unit 20. The shielding member 24 and the noise detection sensor 27 are provided on other main body side members (such as an arm portion (also referred to as a connecting member) 33 provided so as to protrude from the main body portion 30 and hold the operation panel portion 20). You may do it.

  According to such a configuration, the noise detection sensor 27D can detect the electromagnetic wave noise from the MFP 10 without detecting the approach of the user's finger to the operation unit 6 (operation panel unit 20).

  Similarly to the above embodiments, when electromagnetic wave noise is detected by the proximity detection sensor 21, the electromagnetic wave noise (from the MFP 10) can be detected by the noise detection sensor 27. Therefore, it is possible to suppress erroneous detection caused by a single electromagnetic wave noise, and it is possible to appropriately detect a user operation on the operation panel unit 20.

<5. Fifth Embodiment>
The fifth embodiment is a modification of the fourth embodiment. Below, it demonstrates centering on difference with 4th Embodiment.

  In the fourth embodiment, the noise detection sensor 27 is arranged not on the detachable operation panel unit 20 but on the main body side of the MFP 10 and shielded by the shielding member 24. The fifth embodiment exemplifies a mode in which the noise detection sensor 27 (27E) is disposed on the main body side of the MFP 10 and is not shielded by a shielding member.

  FIG. 17 is a view showing the vicinity of the operation panel 20 (20E) of the MFP 10 (10E) according to the fifth embodiment. As shown in FIG. 17, as can be seen from comparison with FIG. 16, the MFP 10 </ b> E is not provided with the shielding member 24 for the noise detection sensor 27.

  Here, it is assumed that the operation panel unit 20E is arranged at a position separated from the main body unit 30 of the MFP 10. Specifically, the operation panel unit 20E is placed on a table adjacent to the MFP 10 after the operation panel unit 20E is removed from the main body side of the MFP 10 as indicated by a white arrow in FIG. To do.

  In the fifth embodiment, in such an arrangement state, an adjustment operation for adjusting the sensitivity of the noise detection sensor 27 in advance is performed. Specifically, an adjustment user operation that is a test user operation on the operation unit is performed. At that time, the sensitivity of the noise detection sensor is reduced until the noise detection sensor 27 does not respond to the adjustment user operation. Thereby, the excessive reaction of the noise detection sensor 27 is avoided.

  Such an adjustment operation is executed using the noise detection sensor 27, the approach detection sensor 21, and the like under the control of the sensitivity adjustment unit 13 (see FIG. 18) in the controller 9. FIG. 18 is a diagram showing functional blocks of the MFP 10 according to the fifth embodiment. As shown in FIG. 18, the controller 9 further includes a sensitivity adjustment unit 13 that adjusts the sensitivity of the noise detection sensor.

  FIG. 19 is a flowchart showing the adjustment operation of the noise detection sensor 27. Such an adjustment operation may be performed at an appropriate timing as required. Further, it is assumed that the sensitivity of the noise detection sensor 27 is initially set to a predetermined value (relatively high value) that appropriately detects noise from the MFP 10.

  In step S11, a sensitivity adjustment operation by the user (specifically, an adjustment user operation that is a test user operation) is performed. Specifically, the user performs an operation (operation) in which his / her finger approaches the touch panel 25.

  In step S12, the approach detection sensor 21 detects a signal (approach detection signal) corresponding to the adjustment user operation in step S11.

  In step S13, it is determined whether or not the noise detection sensor 27 has detected a signal (noise detection signal) resulting from the adjustment user operation.

  When the noise detection sensor 27 does not detect a signal, it is determined that the sensitivity of the noise detection sensor 27 is sufficiently low, and this process is terminated as it is.

  On the other hand, when the noise detection sensor 27 is also detecting a signal, it is determined that the sensitivity of the noise detection sensor 27 is still high, and the process proceeds to step S14. In step S14, the sensitivity of the noise detection sensor 27 is reduced by a predetermined amount (a minute amount). And it progresses to step S11 again.

  Thereafter, the same processing is repeated. Thus, when the adjustment user operation is performed, the sensitivity of the noise detection sensor 27 is reduced until the noise detection sensor 27 does not respond to the adjustment user operation.

  According to this, it is possible to avoid an excessive reaction of the noise detection sensor 27 without using the shielding member 24.

  Thereafter, it is assumed that the MFP 10 is in the sleep mode while the operation panel unit 20E is placed on a table adjacent to the MFP 10. In other words, a situation is assumed in which the operation panel unit 20E is disposed at a position separated from the main body unit 30 of the MFP 10 and is in the sleep mode. In such a situation, the presence / absence of a user operation on the operation panel unit 20 is determined using the proximity detection sensor 21 and the noise detection sensor 27 as in the above embodiments, and the sleep result is determined using the determination result. It is determined whether or not to return from the mode to the normal mode.

  In such a determination operation, the detection result of electromagnetic wave noise using the noise detection sensor 27 is used as in the above embodiments. Therefore, it is possible to suppress erroneous detection caused by a single electromagnetic wave noise, and it is possible to appropriately detect a user operation on the operation panel unit 20.

<6. Modified example>
Although the embodiments of the present invention have been described above, the present invention is not limited to the contents described above.

  For example, in each said embodiment, although the aspect in which the four proximity detection sensors 21 are arrange | positioned so that the outer periphery part of the touch panel 25 may be enclosed is illustrated, it is not limited to this. For example, other numbers (for example, two) of proximity detection sensors 21 may be arranged so as to surround the outer peripheral edge of the touch panel 25. Alternatively, one or a plurality of proximity detection sensors 21 may be arranged so as to surround both the touch panel 25 and the operation keys 22 (see FIG. 3).

  Moreover, in the said 1st-4th embodiment, although the aspect in which mixing of the electromagnetic wave noise to the noise detection sensor 27 is prevented using the shielding member 24 is illustrated, it is not limited to this. For example, an electromagnetic wave absorbing member that absorbs electromagnetic waves may be provided in place of the shielding member (electromagnetic shield member) 24.

10, 10A to 10E MFP (image forming apparatus)
20, 20A to 20E Operation panel unit 21 Proximity detection sensor 24, 24A to 24E Shield member (electromagnetic shield member)
25 Touch Panel 27, 27A to 27E Noise Detection Sensor 30 Body Part 32 Base Part 33 Arm Part

Claims (13)

An image forming apparatus,
An operation unit;
An approach detection sensor for detecting an approach of a user's finger to the operation unit;
A noise detection sensor for detecting electromagnetic wave noise from the image forming apparatus without detecting an approach of a user's finger to the operation unit;
Determining means for determining presence or absence of a user operation on the operation unit;
With
The determination means includes
It is determined that a user operation on the operation unit has been performed on the condition that a noise detection signal from the noise detection sensor is not acquired in addition to an acquisition of a proximity detection signal from the proximity detection sensor. Image forming apparatus. The image forming apparatus according to claim 1.
An electromagnetic shielding member that is disposed between the proximity detection sensor and the noise detection sensor and suppresses an influence on the noise detection sensor by a user operation on the operation unit;
An image forming apparatus further comprising: The image forming apparatus according to claim 1.
An electromagnetic wave absorbing member that is disposed between the proximity detection sensor and the noise detection sensor and reduces an influence on the noise detection sensor by a user operation on the operation unit;
An image forming apparatus further comprising: The image forming apparatus according to any one of claims 1 to 3,
The image forming apparatus, wherein the noise detection sensor is provided closer to the main body of the image forming apparatus than the proximity detection sensor. The image forming apparatus according to claim 2 or 3,
The operation unit has an operation panel unit,
The proximity detection sensor is provided on the front side of the operation panel unit,
The image forming apparatus, wherein the noise detection sensor is provided on a back side of the operation panel unit. The image forming apparatus according to claim 5.
The operation unit has an operation panel unit,
The proximity detection sensor is provided on the front side of the operation panel unit,
The image forming apparatus, wherein the noise detection sensor is provided in a loop shape on the back side of the operation panel unit. The image forming apparatus according to claim 5.
The operation unit has an operation panel unit,
The proximity detection sensor is provided on the front side of the operation panel unit,
The image forming apparatus, wherein the noise detection sensor is linearly provided on a back side of the operation panel unit. The image forming apparatus according to claim 5.
The operation unit has a detachable operation panel unit,
The proximity detection sensor is provided on the front side of the operation panel unit,
The noise detection sensor is disposed away from the outer edge portion of the operation panel unit in the central portion on the back side of the operation panel unit,
The sensitivity of the noise detection sensor is reduced to such an extent that the noise detection sensor does not react to a user operation from the front side with respect to the outer edge portion of the operation panel unit. The image forming apparatus according to claim 1.
The operation unit has a detachable operation panel unit that can be attached to and detached from the main body of the image forming apparatus.
The proximity detection sensor is provided in the operation panel unit,
The noise detection sensor is provided on the main body side of the image forming apparatus,
An image forming apparatus, wherein an electromagnetic shielding member or an electromagnetic wave absorbing member is disposed between the noise detection sensor and the operation panel unit on a main body side of the image forming apparatus. The image forming apparatus according to claim 1.
Adjusting means for adjusting the sensitivity of the noise detection sensor;
Further comprising
The operation unit has a detachable operation panel unit that can be attached to and detached from the main body of the image forming apparatus.
The proximity detection sensor is provided in the operation panel unit,
The noise detection sensor is provided on the main body side of the image forming apparatus,
The adjustment unit is configured such that when the adjustment user operation, which is a test user operation on the operation unit, is performed in a state where the operation panel unit is detached from the main body of the image forming apparatus, the noise detection sensor An image forming apparatus, wherein the sensitivity of the noise detection sensor is reduced until no response is made to an adjustment user operation. The image forming apparatus according to any one of claims 1 to 10,
The image forming apparatus, wherein the proximity detection sensor and the noise detection sensor are proximity sensors of the same type. 12. The image forming apparatus according to claim 1, wherein:
The image forming apparatus according to claim 1, wherein the proximity detection sensor is provided around a touch panel on a front side of the operation panel unit of the operation unit. The image forming apparatus according to any one of claims 1 to 12,
A state control unit for returning the image forming apparatus from a power saving mode when it is determined that a user operation is performed on the operation unit;
An image forming apparatus further comprising:

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