JP2016171386A - Image formation device with human body detection sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image formation device that returns from a power saving mode in response to the approximation of a person, and on the other hand, that can prevent unnecessary return with a simple configuration.SOLUTION: An image formation device with a human body detection sensor comprises: an operation unit for accepting operation; a communication unit for receiving an instruction from the outside; an image formation unit for performing a job involved in image formation on the basis of the operation or instruction; a storage unit for storing the performed job as history; a human body detection sensor that detects a human body situated in a detection region within a predetermined range and its sensitivity can be set; and a control unit that cancels a power saving mode responding to detection by the human body detection sensor or accepted operation during the power saving mode and causes the image formation unit to perform a job, or cancels the power saving mode responding to an instruction and causes the image formation unit to perform a job. If the ratio of jobs based on operation to the history is less than a predetermined threshold value, the control unit sets the sensitivity of the human body detection sensor to a value lower than normal setting.SELECTED DRAWING: Figure 4

Description

  The present invention relates to an image forming apparatus with a human body sensor, and more particularly to an image forming apparatus that returns from a power saving mode in response to a user's detection by the human body sensor.

  There is known an image processing apparatus having a plurality of power modes including a power saving mode and a normal mode in which the power consumption of the apparatus is different from each other. In such an image forming apparatus, a human sensor that senses the human body is mounted, and when the human sensor detects that a person (user) is approaching, the operation panel is displayed and the power saving mode is canceled and the normal mode is released. What is known to return to Compared with the display and cancellation of the power saving mode after the operation panel is operated, the user can feel that the return time from the power saving mode has been shortened. This is because the completion of the return from the power saving mode is advanced for the user during the period from when the human sensor detects the user until the user approaches the operation panel and performs the operation.

However, even when a person approaches the image forming apparatus for other reasons than for using the image forming apparatus, the power saving mode is restored by the detection of the human sensor, resulting in useless power consumption. .
On the other hand, when the human sensor detects the approach of a person during the power saving mode, it communicates with an RFID tag owned by the approaching person to acquire a user ID, and whether the approaching person is a preset excluded person or not. A job processing apparatus for determining whether or not is proposed has been proposed (for example, see Patent Document 1).
In this job processing apparatus, when the person is not an excluded person, the power saving mode is canceled and the normal mode is switched. However, in the case of an excluded person, the power saving mode is not canceled due to the approach of the person, and the power saving mode is canceled in response to an operation or document setting by the person. With such a configuration, it is possible to cancel the power saving mode in response to the approach of a person after excluding a person who has approached for purposes other than the purpose of using the device.

JP2013-55618A

In Patent Document 1, it is necessary that each target person has an RFID. Further, in order to specify a person from the RFID, a process for registering an excluded person in advance, a server for managing registration data, and the like are required. It is.
Even if there is some misdetection, there is a need for a method that can return from the power saving mode in response to the approach of a person with a simpler configuration, while preventing unnecessary return. In recent years, the number of image forming apparatuses having a single function has decreased, and the ratio of apparatuses that execute a plurality of types of jobs, such as digital multifunction peripherals, has increased. In a digital multi-function peripheral, there are jobs that are executed based on user operations accepted by the operation unit, such as copy jobs and scanner jobs, and jobs that are executed based on instructions received from external devices, such as print jobs. For copy jobs and scanner jobs, the apparent time required to return from the power saving mode is reduced by detecting the user and releasing the power saving mode before the user approaches the operation unit. However, if a user who simply picks up a print sheet output in a print job is detected and the power saving mode is canceled, power is wasted due to the return from the unnecessary power saving mode.
The present invention has been made in view of the above circumstances, and provides an image forming apparatus capable of returning from the power saving mode in response to the approach of a person while preventing unnecessary return with a simple configuration. To do.

  The present invention relates to an operation unit that accepts an operation from a user related to image formation processing, a communication unit that receives an instruction from an external device, and an image formation that executes a job related to image formation based on the operation or the instruction , A storage unit that stores the executed job as a history, a human body sensor that senses a human body located in a sensing area within a predetermined range from the operation unit, and can set sensitivity, and in a power saving mode In response to sensing of the human body or in response to the operation, the power saving mode is canceled, and the image forming unit is caused to execute a job based on the operation or a newly received operation, or in response to the instruction. A control unit that cancels the power mode and executes the job, and the control unit, when a ratio of the job based on the operation to the history is lower than a predetermined threshold Serial to provide sensitivity of the human body sensing image forming apparatus with a sensor for lower than normal setting of the human body detection sensor.

In the image forming apparatus according to the present invention, when the proportion of the job history based on the operation is lower than a predetermined threshold, the sensitivity of the human body sensor is lower than a normal setting, so While reacting and returning from the power saving mode, an unnecessary return can be prevented with a simple configuration.
In other words, the type of job executed is determined based on the history, and the sensitivity of the human body sensor is set to cancel the power saving mode and switch to the normal mode in accordance with the actual state of use of the image forming apparatus. , That is, switching between both modes can be controlled. For example, by setting the sensitivity of the human body sensor low for a user who has many print jobs, it is possible to reduce useless recovery from the power saving mode.

1 is a perspective view showing an external appearance of a digital multi-function peripheral that is an embodiment of an image forming apparatus of the present invention. FIG. 2 is a plan view of the digital multifunction peripheral shown in FIG. 1. FIG. 2 is a cross-sectional view illustrating a mechanical configuration of a main body portion of the digital multifunction peripheral illustrated in FIG. 1. FIG. 2 is a block diagram illustrating an electrical configuration of the digital multifunction peripheral illustrated in FIG. 1. 3 is a flowchart illustrating processing in which the control unit of the digital multi-function peripheral illustrated in FIG. 1 determines whether to cancel a power saving mode based on detection by a human body sensor. It is explanatory drawing which shows an example of the log | history stored in the memory shown in FIG. It is explanatory drawing which shows an example from which the log | history stored in the memory shown in FIG. 4 differs. It is explanatory drawing which shows an example of the threshold value stored in the memory shown in FIG. It is explanatory drawing which shows an example from which the threshold value stored in the memory shown in FIG. 4 differs.

Hereinafter, the present invention will be described in more detail with reference to the drawings. In addition, the following description is an illustration in all the points, Comprising: It should not be interpreted as limiting this invention.
(Embodiment 1)
FIG. 1 is a perspective view showing an external appearance of a digital multi-function peripheral which is an embodiment of an image forming apparatus according to the present invention. FIG. 2 is a plan view of the digital multifunction peripheral shown in FIG. FIG. 3 is a cross-sectional view showing a mechanical configuration of a main body portion of the digital multi-function peripheral 100 shown in FIG. As shown in FIGS. 1 and 2, the digital multi-function peripheral 100 includes an operation unit 103, a human body sensor 51, and discharge trays 39a and 39b.

As shown in FIG. 3, the digital multifunction peripheral 100 includes a document conveying device 112 that conveys a document to a reading unit, a document reading device 111 that reads a document, an operation unit 103, and an image forming unit 102 that forms an image. . The digital multi-function peripheral 100 executes scanner, print, and copy jobs based on instructions from the user received via the operation unit 103 or a communication unit (not shown in FIGS. 1 and 2).
Further, if the period during which these jobs are not executed or the instruction from the user is not received exceeds a predetermined period, the mode is shifted from the normal mode in which job execution can be started as soon as the instruction is received to the power saving mode. Note that the transition to the power saving mode is performed not only when the standby state has continued for a predetermined period as described above, but also when an explicit user operation is accepted or when a preset time arrives. Also good. Alternatively, it may be performed when the surrounding environment (for example, illuminance or noise level) is set in advance.

  During the power saving mode, energization to each part of the digital multifunction peripheral 100 is cut off or reduced, so that the power consumption is significantly reduced compared to the normal mode. On the other hand, a certain amount of return time is required to return to a state where job execution can be started as soon as an instruction is received. The return time is a period from when energization of each blocked unit is resumed to start execution of the job until each unit is returned to an operable standby state. In other words, it is time to return to the normal mode.

Here, the internal configuration of the digital multifunction peripheral 100 shown in FIG. 3 will be briefly described.
In the digital multifunction peripheral 100, a color image using each color of black (K), cyan (C), magenta (M), and yellow (Y) is printed on a printing sheet. Alternatively, a monochrome image using a single color (for example, black) is printed on a print sheet. Therefore, four each of the developing device 12, the photosensitive drum 13, the drum cleaning device 14, and the charger 15 are provided. In order to form four types of toner images corresponding to each color, four image stations Pa, Pb, Pc, and Pd are configured in association with black, cyan, magenta, and yellow, respectively.

  In each of the image stations Pa, Pb, Pc, and Pd, a toner image is formed as follows. A drum cleaning device 14 removes and collects residual toner on the surface of the photosensitive drum 13. Thereafter, the charger 15 uniformly charges the surface of the photosensitive drum 13 to a predetermined potential. The optical scanning device 11 exposes the uniformly charged surface to form an electrostatic latent image on the surface. Thereafter, the developing device 12 develops the electrostatic latent image. As a result, a toner image of each color is formed on the surface of each photosensitive drum 13.

  Further, the intermediate transfer belt 21 moves around in the arrow direction C. The belt cleaning device 22 removes and collects residual toner from the intermediate transfer belt 21 that moves around. Each color toner image on the surface of each photoconductor drum 13 is sequentially transferred to the intermediate transfer belt 21 and superimposed thereon, so that a color toner image is formed on the intermediate transfer belt 21.

  The print sheet is pulled out from any one of the four feeding trays 18 by the pickup roller 33 and is fed to the secondary transfer device 23 via the sheet conveyance path R1. Alternatively, the sheet is fed from the manual feed tray 19 by a pickup roller (not shown) and is fed to the secondary transfer device 23 via the sheet conveyance path R1. In the sheet conveyance path R1, a registration roller 34 that temporarily stops the printing sheet and aligns the leading edge of the printing sheet is disposed. Further, a conveyance roller 35 and the like for urging conveyance of the print sheet are disposed. The registration roller 34 temporarily stops the print sheet, and then conveys the print sheet to the nip area between the intermediate transfer belt 21 and the transfer roller 23a in accordance with the transfer timing of the toner image.

A nip area is formed between the transfer roller 23 a of the secondary transfer device 23 and the intermediate transfer belt 21. When the print sheet passes through the nip, a color toner image formed on the surface of the intermediate transfer belt 21 is transferred to the print sheet. After passing through the nip region, the print sheet is sandwiched between the heating roller 24 and the pressure roller 25 of the fixing device 17 and heated and pressed. By this heating and pressurization, the color toner image is fixed on the print sheet.
The print sheet that has passed through the fixing device 17 is discharged to a discharge tray 39a or 39b through a discharge roller 36a or 36b. The print sheet discharge destination is controlled by an image formation control unit 101a described later, and the conveyance path is switched so that the print sheet is guided to one of the discharge trays 39a and 39b by a switching mechanism (not shown). Since the printing sheet conveyance path switching mechanism is well known in the technical field of image forming apparatuses, detailed illustration thereof is omitted.

Next, the electrical configuration of the digital multifunction peripheral 100 will be briefly described.
FIG. 4 is a block diagram illustrating an electrical configuration of the digital multifunction peripheral 100 according to the present embodiment. In FIG. 4, a control unit 101 controls the digital multifunction peripheral 100 in an integrated manner, and includes a CPU, a RAM, a ROM, various interface circuits, and the like. The control unit 101 includes the functions of the image formation control unit 101a and the power saving control unit 101b. The image formation control unit 101 a manages job execution based on the operation received by the operation unit 103 and job execution based on an instruction received by the communication unit 55 and controls the operation of the image formation unit 102. The power saving control unit 101 b manages switching between the power saving mode and the normal mode and controls the human body sensor 51.
The image forming unit 102 prints a print image on a print sheet by an electrophotographic method. The image forming unit 102 includes electrical components related to the optical scanning device 11, the developing device 12, the photosensitive drum 13, the drum cleaning device 14, and the charger 15 in FIG. 1. Further, it includes electrical components relating to the intermediate transfer belt 21, the fixing device 17, the sheet conveyance path R1, the feeding tray 18, and the discharge trays 39a and 39b.

The human body sensor 51 will be described later.
The communication unit 55 is a communication interface circuit and firmware that exchanges communication data with an external device and receives a print job execution request from, for example, an external computer.
The operation unit 103 includes a plurality of input keys and a liquid crystal display device. The memory 104 is a non-volatile storage unit such as a hard disk device (HDD) or a flash memory, for example, and stores various data and programs including a history 104a of executed jobs and a threshold 104b related to sensitivity setting of the human body sensor 51. Store.

For example, the control unit 101 controls the image reading device 111 and the document conveying device 112 to convey the document by the document conveying device 112. Then, an image of the original is read by the image reading device 111, and image data indicating the image of the original is stored in the memory 104. Further, the image forming unit 102 is controlled to cause the image forming unit 102 to print an image of a document indicated by the image data in the memory 104 on a print sheet.
The above is the outline of the configuration of the digital multifunction peripheral 100.

Return to the description of the power saving mode.
In this embodiment, since the image forming unit 102 forms an image by electrophotography, the image forming unit 102 includes a fixing device 17 that heats the toner transferred to the print sheet to a predetermined temperature and fixes the toner on the print sheet. The control unit 101 realizes power saving by lowering the control temperature of the heating roller 24 of the fixing device 17 during the power saving mode as compared with the normal mode. When returning to the normal mode, it takes time to raise the temperature of the heating roller 24 to the predetermined temperature.

Further, the control unit 101 realizes power saving by cutting off the power supply to the document reading device 111 that reads the document during the power saving mode. When returning to the normal mode, it takes time until the characteristics are stabilized by resuming energization of the document reader 111. A calibration operation may be performed as necessary.
When receiving a print job instruction in the power saving mode, the control unit 101 serves as the power saving control unit 101b to temporarily return each part of the digital multifunction peripheral 100 from the power saving mode to the normal mode. Further, after the completion of the return from the power saving mode, the control unit 101 starts execution of a print job based on the instruction received by the communication unit 55 as the image formation control unit 101a. After the print job is completed, the control unit 101 performs a process of shifting to the power saving mode as the power saving control unit 101b.
In the case of a copy job or a scanner job, a job start instruction is received from the user via the operation unit 103. In other words, the image formation control unit 101a starts executing a copy job or a scanner job based on the operation accepted by the operation unit 103. The human body sensor 51 senses that the user has come to the operation unit 103 to operate the operation unit 103, and cancels the power saving mode before the user operates the operation unit 103.

In FIG. 2, a semicircular sensing area 53 indicates an area where the human body sensor 51 senses a human body. When the user enters the sensing area 53, the human body sensor 51 senses the user.
The human body sensor detects an approximate distance to the sensed human body. As the human body sensor 51, an ultrasonic sensor or a pyroelectric sensor can be applied.

The digital multifunction peripheral 100 has two discharge trays 39a and 39b. One of them, the discharge tray 39 a, is disposed below the operation unit 103.
For example, when receiving a request for a print job, the image formation control unit 101a discharges the print sheet to the discharge tray 39a. On the other hand, when a request for a copy job is received, control is performed to discharge the print sheet to the discharge tray 39b.

≪Processing and history of power saving control unit, threshold value≫
Processing as the power saving control unit 101b of the control unit 101 will be further described.
FIG. 5 is a flowchart illustrating processing in which the control unit 101 of the digital multi-function peripheral illustrated in FIG. 1 determines whether to cancel the power saving mode based on detection by the human body sensor 51. That is, when the human body sensor 51 detects a human body during the power saving mode, the power saving control unit 101b refers to the history 104a and the threshold value 104b stored in the memory 104 to determine whether or not to cancel the power saving mode. The procedure to judge is shown.

As shown in FIG. 5, the control unit 101 as the power saving control unit 101b first checks whether or not the current mode is the power saving mode (step S9). If it is not the power saving mode, no processing related to the cancellation of the power saving mode is performed (No loop in step S9).
On the other hand, if in the power saving mode (Yes in step S9), the power saving control unit 101b sequentially checks whether the human body sensor 51 has detected a person (step S11). When the human body sensor 51 detects a person (Yes in step S11), the power saving control unit 101b refers to the history 104a in response (step S13). The history 104a is data indicating attributes of jobs executed in the past. The power saving control unit 104a calculates the ratio of the number of print jobs to the total number of jobs stored in the history, that is, the print job rate.
FIG. 6 is an explanatory diagram showing an example of the contents of the history stored in the history 104a. As shown in FIG. 6, the history 104a stores, for each user, how many times each user has executed a print job, a copy job, or a scanner job in the digital multifunction peripheral 100 during a certain past period (for example, six months). Yes.

For example, in FIG. 6, the user with the user ID 0001 has executed a print job 150 times, a copy job once, and a scanner job once in the past six months. Most of the executed jobs are print jobs. For other users (user IDs 0002, 0003, 0004, and 0005), the number of times that a print job, a copy job, and a scanner job are executed is stored. In order to make the explanation easy to understand, the number of users is limited to five in FIG. 6, but more user histories may be stored.
When using the digital multifunction peripheral 100, each user performs user authentication and then uses the digital multifunction peripheral 100. The control unit 101 associates a job executed based on the user authentication with each user in the history 104a. Store.

  FIG. 7 is an explanatory diagram showing an example of the history stored in the history 104a that is different from FIG. For example, the history of the image forming apparatus installed in a different place from the image forming apparatus according to FIG. 6 and used by different users. Compared to FIG. 6, the history of FIG. 7 accounts for a large proportion of the copy job and the scanner job. The number of users is limited to five so that it can be easily compared with FIG. 6, but more user histories may be stored.

Return to the description of the flowchart. After calculating the print job rate based on the history 104a (step S13), the power saving control unit 101b refers to the threshold 104b (step S15). The threshold 104b is data storing a threshold value to be compared with the calculated print job rate.
FIG. 8 is an explanatory diagram illustrating an example of the threshold value stored in the threshold value 104b. As shown in FIG. 8, the threshold 104b stores values divided into a plurality of stages according to the print job rate. Here, the specific contents of the threshold are the width of the sensing area of the human body sensor and the sensing period. The example shown in FIG. 8 has three stages: setting A corresponding to a print job rate of less than 20%, setting B corresponding to a case of 20% or more and less than 80%, and setting C corresponding to a case of 80% or more. An example is shown. Of course, this is only an example.

The power saving control unit 101b is configured such that the distance of the person detected by the human body sensor 51 is within the range of the sensing area defined according to the print job rate with the threshold 104b, and the period during which the person is detected is It is determined whether or not a period longer than the sensing period defined by the threshold 104b is detected. When it is determined that the detected person has been detected within the sensing area beyond the sensing period (Yes in Step S17), the power saving control unit 101b cancels the power saving mode and returns to the normal mode (Step S17). S19). Thereafter, the routine returns to step S9 described above.
On the other hand, when the detection of the human body sensor 51 does not satisfy the condition of step S17 (No in step S17), the routine returns to the above-described step S11 and sequentially monitors the detection result of the human body sensor.
The above is the flow of processing in which the power saving control unit 101b cancels the power saving mode based on the detection of the human body sensor 51.

Here, the threshold value 104b will be further described.
The power saving control unit 101b determines the sensitivity of the human sensor, that is, the width of the sensing area and the sensing period, according to the print job rate for all users. For example, when the calculated print job rate is 81%, this corresponds to a case where the print job rate is 80% or more, and the power saving control unit 101b applies the threshold value of setting C. In other words, the smallest sensing area of the three predetermined areas is applied as the sensing area. Further, the longest period among the three stages determined in advance as the sensing period is applied.

When the print job rate is 81%, it can be said that the printer is mainly used. In other words, among the people detected by the human body sensor 51, it can be considered that many people come to pick up the printed sheet. Therefore, even if the human body sensor 51 detects a person, the above threshold value is set so as to avoid as much as possible that a person who has just come to pick up a print sheet will not wastefully return from the power saving mode. ing.
Specifically, when setting C is applied, the power saving mode is canceled when a person is detected over a long period in the determination of step S17 in the flowchart shown in FIG. Since the sensitivity for detecting a person is substantially reduced, it is expected that the power saving mode is erroneously canceled. In addition, a person is not detected unless the sensing area is within the minimum area (for example, the distance from the human body sensor 51 is 30 cm). Even if there is only a person passing near the operation unit 103, it is difficult to detect, and it is expected that the power saving mode is erroneously canceled.

On the other hand, when the print job rate is low, it can be said that copy jobs or scanner jobs are mainly used. Under such a usage environment, when it is detected that a person has approached the operation unit 103, the power saving mode is more positively canceled and the normal mode is restored, and the waiting time of the user before starting the job is shortened. It is preferable to do.
Specifically, when the setting A corresponding to a print job rate of 18% and less than 20% is applied, for example, a person is detected in a short period in the determination of step S17 of the flowchart shown in FIG. Even if a person is detected. In effect, the sensitivity of the human body sensor 51 is set large.

(Embodiment 2)
As described in the first embodiment, the threshold shown in FIG. 8 defines the sensitivity of the human body sensor 51 as a combination of the width of the sensing area and the sensing period. However, this is only an example. For example, the threshold may be only the width of the sensing area. Or only a sensing period may be sufficient, and also a different element may be sufficient.
FIG. 9 is an explanatory diagram showing an aspect different from FIG. 8 of the threshold value stored in the threshold value 104b. In FIG. 9, the sensitivity of the human body sensor 51 is defined as the width of the sensing area, and the sensing period is fixed to a predetermined value.
The power saving control unit 101b determines a value to be applied as the width of the sensing range of the human body sensor 51 according to the print job rate of all users. When the print job rate is 80% or more, it is determined that the print job is mainly used, and it is not determined that a person has been detected unless a person is detected within 30 cm from the human body sensor 51. As a result, a person who simply passes in front of the operation unit 103 is not detected. As a result, it is expected that the human body sensor 51 detects a person who only passes nearby and cancels the power saving mode in vain.
On the other hand, when the print job rate is less than 20%, it can be determined that the copy job and / or the scanner job are the main usage. Therefore, the detection area is expanded to the maximum, and people are detected in a wide range. Then, by returning from the power saving mode to the normal state in response to human detection, the waiting time of the user who executes the copy job and the scanner job can be omitted or shortened, and convenience is improved.

(Embodiment 3)
In the first embodiment, as shown in FIG. 8, the width of the sensing area and the sensing period are not related to each other, and each is determined only by the print job rate. However, for example, the threshold may be defined in such a manner that the print job rate is further subdivided from FIG. 8, the width of the sensing area is changed as a major classification, and the sensing period is changed as a minor classification in the major classification. . In that case, the values of the small classifications (sensing periods) belonging to different classes of the large classifications may be equal to each other.

(Embodiment 4)
In the first embodiment, the sensitivity of the human body sensor 51 is changed according to the print job rate, but the human body sensor 51 functions in all cases. However, for example, when the print job rate is 90% or more, a mode in which the human body detection sensor 51 is turned off and does not function is conceivable. According to this aspect, when the print job rate is 90% or more, the power saving mode is not canceled even if the user approaches the operation unit 103, and the power saving mode is canceled by operating the operation unit 103. .

As mentioned above,
(I) An image forming apparatus with a human body sensor according to the present invention is based on an operation unit that receives an operation from a user related to an image forming process, a communication unit that receives an instruction from an external device, and the operation or the instruction An image forming unit that executes a job related to image formation, a storage unit that stores the executed job as a history, and a human body located in a sensing region within a predetermined range from the operation unit is detected and sensitivity is set. Possible human body sensor and canceling the power saving mode in response to the human body sensing or the operation during the power saving mode, and executing the job to the image forming unit based on the operation or the newly accepted operation Or a control unit that cancels the power saving mode and executes the job in response to the instruction, and the control unit occupies the history of the job based on the operation When the ratio is lower than a predetermined threshold, the sensitivity of the human body sensor is set lower than a normal setting.
In the present invention, the image forming apparatus executes processing relating to image formation in units of jobs. Specific examples of jobs include print jobs, copy jobs, and scanner jobs. The copy job in the above-described embodiment corresponds to a job executed based on an operation, and the print job corresponds to a job executed based on reception.
The memory in the above-described embodiment corresponds to the storage unit of the present invention.

Furthermore, the preferable aspect of this invention is demonstrated.
(Ii) The control unit may set the human body sensor to one of at least three levels of sensitivity by comparing the ratio with at least two predetermined thresholds.
In this way, by setting the sensitivity of the human body sensor in multiple stages, fine adjustment according to the proportion of the job based on the above operation is realized.

(Iii) The control unit may turn off the human body sensor when the ratio is less than a predetermined threshold.
In this way, when the percentage of the job based on the operation is very small, the cancellation of the power saving mode in response to the detection of the human body sensor is eliminated, and the operation or instruction received by the operation unit is not received. It is possible to cancel the power saving mode in response to any of the above, and it is possible to eliminate the return from the useless power saving mode.

(Iv) When the control unit determines that the ratio of the job based on the operation to the history is equal to or greater than a predetermined threshold in a state where the sensitivity of the human body sensor is set lower than normal, the human body The sensitivity of the sensor may be returned to the normal setting.
In this way, the sensitivity of the human body sensor can be increased as well as lowered according to the processing status of the job stored in the history.

(V) The human body sensor may change the size of the sensing area in accordance with a sensitivity setting.
(Vi) The human body sensor may change a sensing period that is a basis for determining whether or not a human body is located in the sensing area in accordance with a sensitivity setting.
Preferred embodiments of the present invention include combinations of any of the plurality of embodiments described above.
In addition to the embodiments described above, there can be various modifications of the present invention. These modifications should not be construed as not belonging to the scope of the present invention. The present invention should include the meaning equivalent to the scope of the claims and all modifications within the scope.

11: optical scanning device, 12: developing device, 13: photosensitive drum, 14: drum cleaning device, 15: charger, 17: fixing device, 18: feeding tray, 19: manual feed tray, 21: intermediate transfer belt, 22: belt cleaning device, 23: secondary transfer device, 23a: transfer roller, 24: heating roller, 25: pressure roller, 33: pickup roller, 34: registration roller, 35: transport roller, 36a, 36b: discharge roller 39a, 39b: discharge tray, 51: human body sensor, 53: sensing area, 55: communication unit, 100: digital multi-function peripheral, 101: control unit, 101a: image formation control unit, 101b: power saving control unit 102: Image forming unit 103: Operation unit 104: Memory 104a: History 104b: Threshold value 111: Document reading device 112: Document transport devices Pa, Pb, Pc, Pd: Image station, R1: Sheet transport path

Claims (6)

An operation unit that receives an operation from a user related to the image forming process;
A communication unit that receives instructions from an external device;
An image forming unit that executes a job related to image formation based on the operation or the instruction;
A storage unit for storing the executed job as a history;
A human body sensor that senses a human body located in a sensing region within a predetermined range from the operation unit and can set sensitivity.
Canceling the power saving mode in response to sensing of the human body or the operation during the power saving mode, causing the image forming unit to execute a job or responding to the instruction based on the operation or a newly received operation And a control unit for canceling the power saving mode and executing the job,
The control unit is an image forming apparatus with a human body sensor that lowers the sensitivity of the human body sensor to a normal setting when a ratio of the job based on the operation to the history is lower than a predetermined threshold.   The image forming apparatus according to claim 1, wherein the control unit sets the human body sensor to one of at least three levels of sensitivity by comparing the ratio with at least two predetermined threshold values.   The image forming apparatus according to claim 1, wherein the control unit turns off the human body sensor when the ratio is less than a predetermined threshold.   When the control unit determines that the ratio of the job based on the operation to the history is equal to or more than a predetermined threshold in a state where the sensitivity of the human body sensor is set lower than normal, the control unit of the human body sensor The image forming apparatus according to claim 1, wherein the sensitivity is returned to a normal setting.   The image forming apparatus according to claim 1, wherein the human body sensor changes a width of the sensing area according to a sensitivity setting.   The image forming apparatus according to claim 1, wherein the human body sensor changes a sensing period as a basis for determining whether or not a human body is located in the sensing area according to a sensitivity setting. .