Image forming apparatus

Abstract

To provide an image forming apparatus which further reduces power consumption.SOLUTION: In an image forming apparatus 1, a state detection sensor 24 comprising a light emitting part 24a and a light receiving part 24b, detects a light receiving state of the light receiving part 24b as a state of a predetermined portion. In addition, a state detection sensor management part 42, when a power mode is set to a power-saving mode, intermittently activates the light emitting part 24a based on human body detection conditions corresponding to the output of a human detection sensor part 12, and sets an emission cycle of the light emitting part 24a.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to an image forming apparatus. [Background technology]

[0002] One automatic document feeder is equipped with a document detection means that detects when a document is set in a document tray.The document detection means has a light-emitting element and a light-receiving element, and optically detects the document.The light-emitting element emits light continuously while the document is being transported, and emits light intermittently when the document is not being transported (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2006-243238 Summary of the Invention [Problem to be solved by the invention]

[0004] As described above, power consumption can be reduced by causing the light emitting section to emit light intermittently, but it is preferable to reduce power consumption even further.

[0005] The present invention has been made in view of the above problems, and has an object to provide an image forming apparatus that consumes less power. [Means for solving the problem]

[0006] The image forming apparatus according to the present invention includes a power mode management unit that switches the power mode between a normal mode and a power saving mode that consumes less power than the normal mode, a status detection sensor that optically detects the status of a predetermined part, a status detection sensor management unit, and a human presence sensor unit. The status detection sensor includes a light-emitting unit and a light-receiving unit that can receive light from the light-emitting unit, and detects the light-receiving state of the light-receiving unit as the status of the predetermined part. When the power mode is the power saving mode, the status detection sensor management unit causes the light-emitting unit to emit light intermittently and sets the light emission cycle of the light-emitting unit based on a human body detection condition for the output of the human presence sensor unit. [Effects of the Invention]

[0007] According to the present invention, an image forming apparatus that consumes less power can be obtained.

[0008] The above and other objects, features and advantages of the present invention will become more apparent from the following detailed description taken in conjunction with the accompanying drawings. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a perspective view showing an image forming apparatus according to an embodiment of the present invention. [Figure 2] FIG. 2 is a block diagram showing the electrical configuration of the image forming apparatus shown in FIG. [Figure 3] FIG. 3 is a diagram illustrating the light emission control of the status detection sensor 24 in FIG. [Figure 4] FIG. 4 is a diagram illustrating an example of the correspondence relationship between the human detection distance and the light emission period according to the first embodiment. [Figure 5] FIG. 5 is a diagram illustrating an example of the correspondence relationship between the continuous human detection time and the light emission period in the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0011] Embodiment 1

[0012] Fig. 1 is a perspective view showing an image forming apparatus according to an embodiment of the present invention. Fig. 2 is a block diagram showing the electrical configuration of the image forming apparatus shown in Fig. 1. The image forming apparatus 1 shown in Fig. 1 is a multifunction peripheral having a printing function, an image reading function, a facsimile function, etc.

[0013] 1, the image forming apparatus 1 includes a main body 1a of the image forming apparatus 1, an operation panel 11, and a motion sensor unit 12. As shown in FIG. 2, the image forming apparatus 1 further includes an image reading device 21, a printing device 22, a storage device 23, a status detection sensor 24, and a controller 25 in the main body 1a.

[0014] The operation panel 11 includes a display device 11a such as a liquid crystal display and an input device 11b such as a touch panel, and displays an operation screen to the user and detects user operations. The display device 11a displays the operation screen to the user, and the input device 11b accepts user operations input by the user.

[0015] The human sensor unit 12 is a sensor that detects a human body (a user of the image forming apparatus 1) within a predetermined range in front of the image forming apparatus 1 using infrared rays, ultrasonic waves, or the like.

[0016] The image reading device 21 is an internal device that optically reads an original image from an original and generates image data of the original image. The image reading device 21 includes an image reading unit, an automatic document feeder, etc. The image reading unit irradiates the original with light and detects the light reflected from the original as an original image using a light receiving element such as a line sensor, and outputs image data of the original image. The automatic document feeder feeds originals one by one from a paper feed tray, transports them to the image reading unit, and transports them from the image reading unit to a paper output tray.

[0017] The printing device 22 is an internal device that prints an image on a printing sheet by, for example, electrophotography. In a copy job, the printing device 22 prints a copy image based on the above-mentioned original image on a printing sheet.

[0018] The storage device 23 is a non-volatile storage device (such as a flash memory) that stores programs and data required for the operation of the image forming apparatus 1.

[0019] The status detection sensor 24 is a sensor that optically detects the status of a predetermined portion. Specifically, the status detection sensor 24 includes a light-emitting portion 24a such as an LED and a light-receiving portion 24b such as a phototransistor that can receive light from the light-emitting portion 24a, and detects the status of the predetermined portion as the light-receiving state of the light from the light-emitting portion 24a by the light-receiving portion 24b.

[0020] For example, the status detection sensor 24 detects whether or not a document is placed on the automatic document feeder of the image reading device 21, detects whether the document cover (including the automatic document feeder) of the image reading device 21 is open or closed, detects whether the paper feed cassette of the printing device 22 is open or closed, and detects whether the toner container of the printing device 22 is attached or detached.

[0021] The controller 25 also includes a computer having a CPU (Central Processing Unit), ROM (Read Only Memory), RAM (Random Access Memory), etc. (not shown), and by loading a program stored in the ROM or a non-volatile storage device (not shown) into the RAM and executing the program on the CPU, it controls internal devices such as the image reading device 21 and the printing device 22 and executes jobs requested by the user.

[0022] The controller 25 also operates as a power mode management unit 41 and a status detection sensor management unit 42 .

[0023] The power mode management unit 41 switches the power mode of the image forming apparatus 1 between a normal mode and a power saving mode that consumes less power than the normal mode. Specifically, in the power saving mode, the power mode management unit 41 uses a power control unit (not shown) to stop the operation of predetermined functional parts and stop the supply of power to predetermined functional parts, thereby reducing power consumption compared to the normal mode.

[0024] For example, the power mode management unit 41 sets the power mode to the normal mode when the image forming apparatus 1 is started up, and then switches the power mode to the power saving mode if a predetermined length of no operation period or a predetermined user operation is detected in the normal mode. Also, if a predetermined user operation or receipt of a job request is detected in the power saving mode, the power mode management unit 41 returns the power mode from the power saving mode to the normal mode.

[0025] Fig. 3 is a diagram illustrating light emission control of the status detection sensor 24 in Fig. 1. When the above-mentioned power mode is the power saving mode, the status detection sensor management unit 42 causes the light emitting unit 24a of the status detection sensor 24 to emit light intermittently and sets the light emission cycle of the light emitting unit 24a based on the human body detection condition for the output of the human sensor unit 12, for example, as shown in Fig. 3.

[0026] Here, the length of the light emission period is fixed, and a light emission period of a length corresponding to the human body detection condition is set. Also, here, when the above-mentioned power mode is the normal mode, the status detection sensor management unit 42 causes the light emitting unit 24a of the status detection sensor 24 to emit light continuously, or sets the light emission period of the light emitting unit 24a to a light emission period equal to or shorter than the minimum light emission period in the power saving mode.

[0027] FIG. 4 is a diagram illustrating an example of the correspondence relationship between the human detection distance and the light emission cycle in the first embodiment. In the first embodiment, for example, as shown in FIG. 4, the human body detection condition is a condition of the distance at which a human body is detected, and the status detection sensor management unit 42 lengthens the light emission cycle as the distance (i.e., the human detection distance) increases. Note that the light emission cycle may be increased or decreased linearly according to the human detection distance, as shown in FIG. 4, for example, or may be increased or decreased in stages according to the human detection distance. In the case shown in FIG. 4, when the human detection distance is 50 cm or less, the light emission cycle is set to the lower limit (100 ms), and when the human detection distance is in the range of 50 cm to 200 cm, the light emission cycle is linear with respect to the human detection distance and ranges from 100 ms to 1000 ms.

[0028] Furthermore, as shown in FIG. 4, for example, the status detection sensor management unit 42 turns off the light emitting unit 24a when the human detection distance exceeds a predetermined threshold value (for example, 200 cm).

[0029] Next, the operation of the image forming apparatus 1 according to the first embodiment will be described.

[0030] As described above, after the image forming apparatus 1 is started up, the power mode management unit 41 appropriately sets the power mode to the normal mode or the power saving mode.

[0031] When the power mode is the power saving mode, the status detection sensor management unit 42 determines whether to cause the light emitting unit 24a of the status detection sensor 24 to emit light intermittently or to turn off the light, depending on the output of the human presence sensor unit 12, as described above, and if the light emitting unit 24a of the status detection sensor 24 is to emit light intermittently, it sets the light emission cycle as described above.

[0032] In this way, the light emission control of the status detection sensor 24 is performed, and when the light emitting section 24a of the status detection sensor 24 emits light intermittently, the controller 25 identifies the state of the specific part corresponding to the status detection sensor 24 based on the output of the status detection sensor 24 (light receiving section 24b), and performs processing corresponding to the identified state.

[0033] As described above, according to the first embodiment, the status detection sensor 24 includes the light-emitting unit 24a and the light-receiving unit 24b, and detects the light-receiving state of the light-receiving unit 24b as the state of a predetermined part. When the power mode is the power saving mode, the status detection sensor management unit 42 causes the light-emitting unit 24a to emit light intermittently and sets the light emission cycle of the light-emitting unit 24a based on the human body detection condition for the output of the human sensor unit 12.

[0034] As a result, in the power saving mode, when it is not necessary to detect the condition of a specific part based on the human body detection conditions, the light emitting unit 24a is turned off, and when the light emitting unit 24a is made to emit light intermittently, the light emission cycle is appropriately set based on the human body detection conditions, thereby further reducing power consumption.

[0035] Embodiment 2

[0036] 5 is a diagram illustrating an example of the correspondence relationship between the continuous human detection time and the light emission cycle in the second embodiment. In the second embodiment, the human body detection condition is the time during which a human body is continuously detected. If the time (continuous human detection time) is equal to or greater than a predetermined threshold (e.g., 5 seconds), the status detection sensor management unit 42 causes the light-emitting unit 24a to emit light intermittently at a predetermined light emission cycle (e.g., 100 milliseconds). If the time (continuous human detection time) is less than the predetermined threshold, the status detection sensor management unit 42 turns off the light-emitting unit 24a. In this way, if a human body simply passes in front of the image forming apparatus 1, the light-emitting unit 24a remains off, preventing light emission by the light-emitting unit 24a due to erroneous detection by the user and reducing power consumption.

[0037] However, if the human detection distance exceeds a predetermined threshold, the light emitting unit 24a is turned off regardless of the continuous human detection time.

[0038] The other configurations and operations of the image forming apparatus according to the second embodiment are the same as those of the first embodiment, and therefore the description thereof will be omitted.

[0039] Embodiment 3

[0040] The third embodiment is a combination of the first and second embodiments, and in the third embodiment, the human body detection conditions are the human detection distance and the continuous human detection time. For example, the status detection sensor management unit 42 turns off the light-emitting unit 24a when the human detection distance exceeds a predetermined first threshold (e.g., 100 cm), and when the human detection distance does not exceed the first threshold, causes the light-emitting unit 24a to emit light intermittently at a predetermined light-emitting cycle (e.g., 100 milliseconds) if the continuous human detection time is equal to or greater than a predetermined second threshold (e.g., 2 seconds), and turns off the light-emitting unit 24a if the continuous human detection time is less than the second threshold.

[0041] Here, if the continuous human detection time exceeds a predetermined second threshold, the status detection sensor management unit 42 may cause the light emitting unit 24a to emit light intermittently at an emission cycle according to the human detection distance, as in embodiment 1, for example, and may turn off the light emitting unit 24a if the continuous human detection time does not exceed the predetermined second threshold.

[0042] The other configurations and operations of the image forming apparatus according to the third embodiment are the same as those of the first or second embodiment, and therefore the description thereof will be omitted.

[0043] It should be noted that various changes and modifications to the above-described embodiments will be apparent to those skilled in the art. Such changes and modifications may be made without departing from the spirit and scope of the subject matter and without diminishing its intended advantages. In other words, it is intended that such changes and modifications be included within the scope of the claims. [Industrial Applicability]

[0044] The present invention is applicable to image forming apparatuses such as multifunction peripherals. [Explanation of symbols]

[0045] 1. Image forming device 12 Human sensor unit 24 Status detection sensor 24a Light-emitting part 24b Light receiving part 41 Power mode management unit 42 Condition detection sensor control unit

Claims

1. a power mode management unit that switches the power mode between a normal mode and a power saving mode that consumes less power than the normal mode; a condition detection sensor that optically detects the condition of a predetermined portion; a status detection sensor management unit; Equipped with a human sensor unit, the state detection sensor includes a light-emitting unit and a light-receiving unit capable of receiving light from the light-emitting unit, and detects a light-receiving state of the light-receiving unit as a state of the predetermined portion; the state detection sensor management unit, when the power mode is the power saving mode, causes the light emitting unit to emit light intermittently and sets a light emission cycle of the light emitting unit based on a human body detection condition for an output of the human presence sensor unit; An image forming apparatus comprising:

2. the human body detection condition is a condition of a distance at which a human body is detected, the status detection sensor management unit extends the light emission period as the distance increases; 2. The image forming apparatus according to claim 1, wherein:

3. 3. The image forming apparatus according to claim 2, wherein the state detection sensor management unit turns off the light emitting unit when the distance is equal to or greater than a predetermined threshold value.

4. the human body detection condition is a condition for a time period during which a human body is continuously detected; the status detection sensor management unit causes the light emitting unit to emit light intermittently when the time is equal to or greater than a predetermined threshold, and turns off the light emitting unit when the time is less than the predetermined threshold; 2. The image forming apparatus according to claim 1, wherein:

5. 2. The image forming apparatus according to claim 1, wherein the human body detection conditions are a distance at which a human body is detected and a time period during which a human body is continuously detected.

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