Image forming apparatus and method for controlling the image forming apparatus

Abstract

To reduce power consumption compared to before.SOLUTION: An image forming apparatus that can be transitioned to an operating state, a first power saving state (power saving mode) lower in power consumption than the operating state, and a second power saving state (sleep mode) lower in power consumption than the first power saving state. The image forming apparatus comprises: a fixing unit that fixes a toner image transferred onto a medium to the medium; a fixing control unit that controls the fixing unit; and a state management unit that, when the apparatus is transitioned to the first power saving state (power saving mode), and if the state before the transition is the second power saving state (sleep mode), instructs the fixing control unit not to apply heat to the fixing unit, and if the state before the transition is not the second power saving state, instructs the fixing control unit to apply heat to the fixing unit.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to an image forming apparatus and a control method for an image forming apparatus. [Background technology]

[0002] Conventionally, some image forming devices such as printers have an e-mail receiving function. Some image forming devices of this type access a mail server in a power-saving state that consumes less power than a normal operating state, and when the mail server contains e-mail that needs to be processed in an operating state, the image forming device shifts from the power-saving state to an operating state to receive e-mail from the mail server (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 5632802 Summary of the Invention [Problem to be solved by the invention]

[0004] However, with conventional image forming devices, even when performing operations that do not involve printing, such as receiving e-mail, the device would switch from a power-saving state to an operating state and heat the fixing unit to its standby temperature, resulting in a problem of wasting electricity.

[0005] The present invention has been made in consideration of the above points, and aims to propose an image forming apparatus and a method for controlling an image forming apparatus that can reduce power consumption compared to the prior art. [Means for solving the problem]

[0006] The image forming apparatus of the present invention is an image forming apparatus that can be shifted between an operating state, a first power saving state in which power consumption is lower than that of the operating state, and a second power saving state in which power consumption is lower than that of the first power saving state, the image forming apparatus including: a fixing unit that fixes a toner image transferred onto a medium onto the medium; and a fixing control unit that controls the fixing unit; A receiving unit for receiving data; a state management unit that, when transitioning to the first power saving state, if a state before the transition is the second power saving state, instructs the fixing control unit not to heat the fixing unit, and, if a state before the transition is not the second power saving state, instructs the fixing control unit to heat the fixing unit. and when the data received by the receiving unit while in the second power saving state is data that does not involve printing, the state management unit transitions from the second power saving state to the first power saving state. I made it so that.

[0007] A control method for an image forming apparatus of the present invention is a control method for an image forming apparatus capable of transitioning between an operating state, a first power saving state having lower power consumption than the operating state, and a second power saving state having lower power consumption than the first power saving state, wherein, when transitioning to the first power saving state, if the state before the transition is the second power saving state, a state management unit instructs a fixing control unit that controls a fixing unit that fixes a toner image transferred onto a medium onto the medium not to heat the fixing unit, and if the state before the transition is not the second power saving state, instructs the fixing control unit to heat the fixing unit. and when data received by a receiving unit while in the second power saving state is data that does not involve printing, the state management unit transitions from the second power saving state to the first power saving state. I made it so.

[0008] In this way, when the printer transitions to the first power saving state, if the state before the transition is the second power saving state, the fixing unit is not heated. In other words, even when the printer transitions to the first power saving state, the fixing unit is not necessarily heated, but is heated or not heated depending on the state before the transition. This makes it possible to reduce power consumption compared to when the fixing unit is necessarily heated when the printer transitions to a predetermined state (for example, the first power saving state). Effect of the Invention

[0009] The present invention can realize an image forming apparatus and a method for controlling an image forming apparatus that can reduce power consumption compared to the conventional art. [Brief description of the drawings]

[0010] [Figure 1] FIG. 2 is a diagram illustrating a configuration of a printing mechanism of the image forming apparatus. [Diagram 2] FIG. 2 is a diagram illustrating a functional configuration of an image forming apparatus (in an operating mode and a power saving mode). [Diagram 3] FIG. 2 is a diagram illustrating a functional configuration of an image forming apparatus (in a sleep mode). [Figure 4] FIG. 2 is a diagram illustrating the functional configuration of a controller unit and an engine unit. [Diagram 5] 11 is a timing chart showing the transition of operation modes when the power saving mode is set to "fixing OFF." [Figure 6] 13 is a timing chart showing the transition of operation modes when the power saving mode is set to "low temperature control." [Figure 7] 11 is a flowchart showing an operation procedure at the time of switching between operation modes. [Figure 8] This is a flowchart continuing from Figure 7. [Figure 9] This is a flowchart continuing from Figure 8. [Figure 10] This is a list of protocols that cannot be processed by the unit operating in power-saving mode and involve printing, and a list of protocols that cannot be processed by the unit operating in power-saving mode and do not involve printing. [Figure 11] 13 is a timing chart showing the transition of the operation modes when the power saving mode is set to "low temperature control" and the fixing unit is always heated when the power saving mode is entered. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, modes for carrying out the invention (hereinafter referred to as embodiments) will be described in detail with reference to the drawings.

[0012] [1. Configuration of image forming device] 1 shows the printing mechanism of an image forming apparatus 100. This image forming apparatus 100 is an electrophotographic printer, and on a conveying path R connecting a medium cassette 102 provided at the bottom of an apparatus housing 101 and a medium stacker 103 provided at the top of the apparatus housing 101, a plurality of conveying rollers 104-108, an image forming unit 109, a transfer unit 110, and a fixing unit 111 are provided as the printing mechanism.

[0013] The medium cassette 102 contains the printing medium P. The transport rollers 104 to 108 transport the printing medium P fed from the medium cassette 102 onto the transport path R to the medium stacker 103 along the transport path R. The image forming unit 109 forms a toner image using toner as a developer on a photosensitive drum 112 as an image carrier by an electrophotographic process. The transfer unit 110 transfers the toner image formed on the photosensitive drum 112 by the image forming unit 109 onto the printing medium P transported along the transport path R. The fixing unit 111 fixes the toner image to the printing medium P by applying heat and pressure to the printing medium P to which the toner image has been transferred using a heating roller 113 and a pressure roller 114. The medium stacker 103 stacks the printing medium P to which the toner image has been fixed.

[0014] Furthermore, the image forming apparatus 100 is provided at a predetermined location on the apparatus housing 101 with an operation panel 115 for displaying various types of information and accepting operation inputs.

[0015] Next, Fig. 2 shows an outline of the functional configuration of image forming apparatus 100. Image forming apparatus 100 has a control unit 120, an I / F unit 121, a power saving operation unit 122, a power supply unit 123, and a power switch 124. In Fig. 2, black solid arrows indicate the flow of data, white solid arrows indicate the flow of control, and black dotted arrows indicate the supply of power.

[0016] The control unit 120 has a controller unit 125 and an engine unit 126. The controller unit 125 controls the entire image forming apparatus 100 including the engine unit 126. The engine unit 126 controls the operations of the conveying rollers 104 to 108, the image forming unit 109, the transfer unit 110, and the fixing unit 111, which serve as a printing mechanism, to perform printing on the print medium P.

[0017] The I / F unit 121 has a network I / F 127 and a USB I / F 128. The network I / F 127 connects to an external host PC via a network, and the USB I / F 128 connects to the external host PC via a USB cable.

[0018] The power-saving operation unit 122 monitors the I / F unit 121 in place of the controller unit 125 when the image forming apparatus 100 is in a sleep mode, which will be described later. The power supply unit 123 turns the power to each unit on and off. As indicated by the black dotted arrows in Fig. 2, the power supply unit 123 can turn the power to the control unit 120, the I / F unit 121, and the power-saving operation unit 122 on and off individually.

[0019] In other words, when a user turns on the power switch 124 of the image forming device 100, the power supply unit 123 supplies power to the control unit 120 (controller unit 125 and engine unit 126), the I / F unit 121, and the power-saving operation unit 122, and these are started up to enter an operating state.

[0020] The image forming apparatus 100 has a power saving mode which is a first power saving state in which power consumption is reduced compared to when the apparatus is in operation, and a sleep mode which is a second power saving state in which power consumption is further reduced compared to when the apparatus is in the power saving mode.

[0021] In the power saving mode, power is supplied by the power supply unit 123 to all of the control unit 120 (controller unit 125 and engine unit 126), I / F unit 121, and power saving operation unit 122, but power consumption is reduced compared to the operating state by, for example, setting the temperature of the fixing unit 111 lower than in the operating state. On the other hand, in the sleep mode, as shown in Fig. 3, power supply to the control unit 120 is stopped, thereby further reducing power consumption compared to the power saving mode. The outline of the functional configuration of the image forming apparatus 100 is as described above.

[0022] In this image forming device 100, except in sleep mode, data received from the host PC via I / F unit 121 is processed by controller unit 125 of control unit 120, and if the received data is print data, the print data is passed from controller unit 125 to engine unit 126, and printing based on the print data is performed by engine unit 126.

[0023] On the other hand, in the sleep mode, the power supply to the control unit 120 is stopped, so in the image forming apparatus 100, as described above, the power saving operation unit 122 monitors data reception by the I / F unit 121.

[0024] The power saving operation unit 122 is configured to have only the minimum necessary functions, such as monitoring data reception, in order to reduce the power consumption of the image forming device 100. It has lower processing power than the controller unit 125 and cannot process complex data such as print data.

[0025] For this reason, when the data received by the I / F unit 121 is data that the power-saving operation unit 122 cannot process itself, it instructs the power supply unit 123 to turn on the power of the controller unit 125 (i.e., turn on the power of the control unit 120). Then, the power-saving operation unit 122 stores the data received by the I / F unit 121 in a memory (not shown) accessible from both the power-saving operation unit 122 and the controller unit 125, and hands over the processing of the data to the controller unit 125.

[0026] Here, the functional configuration of the controller unit 125 and engine unit 126 of the control unit 120 will be described in more detail with reference to Fig. 4. Note that the black arrows in Fig. 4 indicate the flow of print data.

[0027] The controller unit 125 has a system control unit 130 , a transmission / reception unit 131 , an image processing unit 132 , an engine communication unit 133 , a status management unit 134 , a panel control unit 135 , and a non-volatile memory 136 .

[0028] The transmitting / receiving unit 131 transmits and receives data to and from the host PC via the network I / F 127 and USB I / F 128 shown in FIG. 2. The image processing unit 132 processes the received print data into image data. The engine communication unit 133 communicates with the engine unit 126. The status management unit 134 manages the status of the image forming apparatus 100. The panel control unit 135 displays various information on the operation panel 115 and accepts operation inputs. The non-volatile memory 136 stores information handled by the controller unit 125. The system control unit 130 manages the operation of the controller unit 125 by issuing instructions to each unit of the controller unit 125.

[0029] On the other hand, the engine unit 126 has an engine control unit 140 , a transport control unit 141 , an image formation control unit 142 , and a fixing control unit 143 .

[0030] The conveyance control unit 141 controls the conveyance rollers 104 to 108 by a motor / clutch (not shown) and the like to convey the print medium. The image formation control unit 142 controls the image forming unit 109 and the transfer unit 110, and forms a toner image on the print medium by an electrophotographic process based on image data processed by the controller unit 125. The fixing control unit 143 controls the fixing unit 111 to fix the toner image transferred onto the print medium to the print medium. The engine control unit 140 issues instructions to each unit of the engine unit 126 based on instructions from the controller unit 125, and controls the image formation process (i.e., the printing operation). The functional configurations of the controller unit 125 and the engine unit 126 of the control unit 120 are as described above.

[0031] [2. Status of image forming device] Next, a detailed description will be given of the states of the image forming apparatus 100. As described above, the state of the image forming apparatus 100 is managed by the state management unit 134 of the controller unit 125. The state of the image forming apparatus 100 includes an operating state in which power is supplied to the controller unit 125 and the engine unit 126, and the image forming apparatus 100 is executing a printing operation, or is waiting to immediately start a printing operation.

[0032] In the image forming apparatus 100 in the operating state, the controller unit 125 is in an operating mode or a standby mode, and executes a printing operation in the operating mode and waits in the standby mode. When the controller unit 125 is in the operating mode, the printing operation is performed with the fixing unit 111 heated to the printing temperature, and when in the standby mode, the fixing unit 111 is kept at a standby temperature (high) lower than the printing temperature.

[0033] Furthermore, the image forming apparatus 100 can be in a first power saving state in which power consumption is reduced more than in the operating state, and a second power saving state in which power consumption is further reduced more than in the first power saving state.

[0034] In the image forming apparatus 100 in the first power saving state, the controller unit 125 is in the power saving mode. In this power saving mode, it is possible to select between "fusing OFF", which is a setting in which the fusing unit 111 is not heated at all in order to reduce power consumption, and "low temperature control", which is a setting in which the fusing unit 111 is kept at a standby temperature (low) lower than the standby temperature (high) in the standby mode. The user can select the setting for the power saving mode (i.e., the selection between "fusing OFF" and "low temperature control") via the operation panel 115. The setting for the power saving mode selected via the operation panel 115 is stored in the non-volatile memory 136 by the system control unit 130 of the controller unit 125.

[0035] When the controller unit 125 is in the power saving mode and set to "fusing OFF," it is configured not to heat the fusing unit 111. On the other hand, when the controller unit 125 is in the power saving mode and set to "low temperature control," it is configured to keep the fusing unit 111 at a standby temperature (low).

[0036] In the second power saving state of the image forming apparatus 100, the controller unit 125 enters the sleep mode. In the sleep mode, as described above, the power supply to the controller unit 125 and the engine unit 126 is stopped.

[0037] In this way, image forming apparatus 100 has an operating mode, a standby mode, a power saving mode, and a sleep mode prepared as operation modes of controller unit 125. The operation modes of controller unit 125 are the operation modes of image forming apparatus 100 as a whole.

[0038] Incidentally, although details will be described later, in the image forming apparatus 100, an operating mode, a standby mode, a power saving mode, and a sleep mode are prepared as operation modes for the engine unit 126 in addition to the controller unit 125. Among these, the standby mode is an operation mode in which the fixing unit 111 is heated to a standby temperature (high) or a standby temperature (low), and the power saving mode is an operation mode in which the fixing unit 111 is not heated.

[0039] [3. Transition of operation mode of image forming device] Here, the transition of the operation modes of the image forming apparatus 100 will be described with reference to the timing charts shown in FIGS.

[0040] Incidentally, FIG. 5 is a timing chart showing an example of operation mode transition when the setting of the controller unit 125 in the power saving mode is "fixing OFF", and FIG. 6 is a timing chart showing an example of operation mode transition when the setting of the controller unit 125 in the power saving mode is "low temperature control".

[0041] First, an example of the transition of operation modes when the power saving mode is set to "fixing OFF" will be described with reference to the timing chart shown in FIG.

[0042] 5, first, at time t0, the image forming apparatus 100 receives print data from the Host PC. Upon receiving the print data, the controller unit 125 goes into operation mode and performs a printing operation based on the received print data. At this time, the engine unit 126 goes into operation mode in response to an instruction from the controller unit 125, heats the fixing unit 111 to a printing temperature, and performs printing on the print medium while maintaining the temperature at the printing temperature.

[0043] When the printing operation ends at time t1, the controller unit 125 transitions from the operating mode to the standby mode. At this time, the engine unit 126 enters the standby mode in response to an instruction from the controller unit 125, and keeps the fixing unit 111 at a standby temperature (high) that is lower than the printing temperature.

[0044] After that, at time t2 after a certain period of time has elapsed, the controller unit 125 transitions from the standby mode to the power saving mode ("fusing OFF"). At this time, since the power saving mode setting is "fusing OFF", the controller unit 125 transitions the engine unit 126 from the standby mode to the power saving mode and stops heating the fusing unit 111.

[0045] At time t3 after a certain period of time has elapsed, the controller unit 125 transitions from the power saving mode to the sleep mode. That is, at this time, the power supply to the controller unit 125 and the engine unit 126 is stopped, and the engine unit 126 also transitions to the sleep mode. After that, at time t4, the power saving operation unit 122 receives data that it cannot process itself and that does not involve printing via the I / F unit 121. Then, the power saving operation unit 122 returns the controller unit 125 from the sleep mode to the power saving mode ("fuser OFF"), and the controller unit 125 takes over the processing of the received data. At this time, because the power saving mode is set to "fuser OFF," the controller unit 125 transitions the engine unit 126 to the power saving mode, thereby keeping the heating of the fuser unit 111 stopped.

[0046] When data processing by controller unit 125 ends at time t5, controller unit 125 and engine unit 126 transition from the power saving mode to the sleep mode. The above is an example of the transition of operation modes when controller unit 125 is set to "fusing OFF" in the power saving mode.

[0047] Next, an example of the transition of the operation mode when the setting of the controller unit 125 in the power saving mode is "low temperature control" will be described with reference to the timing chart shown in FIG.

[0048] 6, first, at time t10, the image forming apparatus 100 receives print data from the Host PC. Upon receiving the print data, the controller unit 125 goes into operation mode and performs a printing operation based on the received print data. At this time, the engine unit 126 goes into operation mode in response to an instruction from the controller unit 125, heats the fixing unit 111 to a printing temperature, and performs printing on the print medium while maintaining the temperature at the printing temperature.

[0049] When the printing operation ends at time t11, the controller unit 125 transitions from the operating mode to the standby mode. At this time, the engine unit 126 enters the standby mode in response to an instruction from the controller unit 125, and keeps the fixing unit 111 at a standby temperature (high) that is lower than the printing temperature.

[0050] After that, at time t12 after a certain period of time has elapsed, the controller unit 125 transitions from the standby mode to the power saving mode ("low temperature control"). At this time, since the power saving mode is set to "low temperature control", the controller unit 125 switches the temperature of the fixing unit 111 from the standby temperature (high) to the standby temperature (low) while keeping the engine unit 126 in the standby mode.

[0051] At time t13 after a certain period of time has elapsed, the controller unit 125 transitions from the power saving mode to the sleep mode. That is, at this time, the power supply to the controller unit 125 and the engine unit 126 is stopped, and the engine unit 126 also transitions to the sleep mode. After that, at time t14, the power saving operation unit 122 receives data that it cannot process itself and that does not involve printing via the I / F unit 121. Then, the power saving operation unit 122 returns the controller unit 125 from the sleep mode to the power saving mode ("low temperature control"), and the processing of the received data is handed over to the controller unit 125. At this time, the power saving mode setting of the controller unit 125 is "low temperature control", but since the previous operation mode was the sleep mode, the engine unit 126 transitions to the power saving mode, thereby keeping the heating of the fixing unit 111 stopped.

[0052] In other words, in the image forming apparatus 100, when the controller unit 125 transitions from sleep mode to power saving mode ("low temperature control") to process data that does not involve printing, even if the power saving mode is set to "low temperature control", the engine unit 126 transitions to the power saving mode instead of the standby mode, and the heating of the fixing unit 111 is kept stopped, so that the fixing unit 111 is not unnecessarily heated.

[0053] When data processing by the controller unit 125 ends at time t15, the controller unit 125 and the engine unit 126 transition from the power saving mode to the sleep mode. The above is an example of the transition of the operation mode when the setting of the controller unit 125 in the power saving mode is "low temperature control."

[0054] [4. Operational procedure when switching between operation modes of image forming devices] Next, the operation procedure of image forming apparatus 100 when switching between operation modes will be described in detail with reference to the flowcharts shown in FIGS.

[0055] 7 is a flowchart showing the operation procedure of the startup process by the controller unit 125. This startup process is executed when the power supply unit 123 turns on the controller unit 125 when the image forming apparatus 100 is powered on or when the image forming apparatus 100 returns from a sleep mode.

[0056] 8 and 9 are flowcharts showing the procedure of the operation mode transition process executed by the controller unit 125 after the start-up process shown in FIG. 7 is completed.

[0057] Here, first, an operational procedure from when the image forming apparatus 100 is turned on until it transitions to a sleep mode will be described with reference to FIGS.

[0058] When the image forming apparatus 100 is powered on, when the power supply unit 123 detects that the power switch 124 has been turned ON, the power supply unit 123 supplies power to the control unit 120, the I / F unit 121, and the power saving operation unit 122, the image forming apparatus 100 enters an operating state, and the startup process shown in FIG. 7 is started.

[0059] When the startup process is started, in the first step SP1, the status management section 134 of the controller section 125 reads out a controller status, which is information indicating the status of the controller section 125, from the nonvolatile memory 136. When the controller section 125 transitions to the sleep mode, a controller status indicating that the controller section 125 is in the sleep mode is stored in the nonvolatile memory 136. For this reason, if the current startup is not a startup resulting from recovery from the sleep mode but a startup resulting from power-on, the controller status indicating that the controller section 125 is in the sleep mode is not stored in the nonvolatile memory 136.

[0060] In the next step SP2, the state management unit 134 obtains a negative result in step SP2 because the controller state indicating the sleep mode is not stored in the non-volatile memory 136, and proceeds to step SP6. In other words, since this startup is not a startup upon returning from the sleep mode but a startup due to power-on, the state management unit 134 proceeds to step SP6. In step SP6, the state management unit 134 sets the controller state to the operating mode, and puts the controller unit 125 into the operating mode.

[0061] Thereafter, in step SP11 shown in FIG. 8, the state management unit 134 waits for the operation (printing operation, initial operation, etc.) of the image forming apparatus 100 to end, and when the operation ends, the process proceeds from step SP11 to step SP12.

[0062] In step SP12, the state management unit 134 instructs the engine unit 126 to transition to standby mode. When the engine control unit 140 of the engine unit 126 receives this instruction via the engine communication unit 133 of the controller unit 125, it instructs the fixing control unit 143 to keep the fixing unit 111 at a standby temperature (high), and transitions the engine unit 126 to standby mode. This keeps the temperature of the fixing unit 111 at the standby temperature (high).

[0063] In the next step SP13, the state management unit 134 of the controller unit 125 sets the controller state to standby mode, putting the controller unit 125 into standby mode, and in the next step SP14, starts a timer for transitioning to the power saving mode. In the next step SP15, the state management unit 134 waits for the timer to time out.

[0064] Here, if an operation event such as receiving print data occurs in step SP16 before the timer times out, the status management unit 134 sets the controller status to the operation mode in the following step SP17, places the controller unit 125 in the operation mode, returns to step SP11, and waits for the image forming device 100 to finish operating.

[0065] On the other hand, if the timer times out without an operation event occurring, in step SP18, the state management unit 134 determines whether the current controller state is standby mode or sleep mode. Here, since the controller state was set to standby mode in step SP13, the state management unit 134 determines that the controller state is standby mode and proceeds to step SP19.

[0066] In step SP19, the state management section 134 reads the setting for the power saving mode ("fixing OFF" or "low temperature control") from the non-volatile memory 136, and if the setting is "fixing OFF", the process proceeds to step SP20.

[0067] In step SP20, state management unit 134 issues an instruction to engine unit 126 to transition to the power saving mode. When engine control unit 140 of engine unit 126 receives this instruction via engine communication unit 133 of controller unit 125, it issues an instruction to fixing control unit 143 to turn off heating of fixing unit 111, and transitions engine unit 126 to the power saving mode. Therefore, at this time, heating of fixing unit 111 is not performed.

[0068] On the other hand, if the setting for the power saving mode read from the non-volatile memory 136 is "low temperature control" in step SP19, the state management section 134 proceeds to step SP21.

[0069] In step SP21, the state management unit 134 instructs the engine unit 126 to switch the standby temperature. When the engine control unit 140 of the engine unit 126 receives this instruction via the engine communication unit 133 of the controller unit 125, it instructs the fixing control unit 143 to switch the temperature of the fixing unit 111 to the standby temperature (low) while keeping the engine unit 126 in the standby mode. This causes the temperature of the fixing unit 111 to be switched from the standby temperature (high) to the standby temperature (low).

[0070] After step SP20 or step SP21, in the following step SP22, the state management section 134 sets the controller state to the power saving mode, puts the controller section 125 into the power saving mode, and proceeds to step SP23 shown in FIG.

[0071] In step SP23, the state management unit 134 starts a timer for transitioning to the sleep mode. In the following step SP24, the state management unit 134 waits for the timer to time out.

[0072] Here, if an operation event such as receiving print data occurs in step SP25 before the timer times out, the status management unit 134 sets the controller status to the operation mode in the following step SP26, places the controller unit 125 in the operation mode, returns to step SP11, and waits for the image forming device 100 to finish operating.

[0073] On the other hand, if the timer times out without an operation event occurring, in step SP27, the state management unit 134 first issues an instruction to the engine unit 126 to transition to the sleep mode as preparation processing for transitioning to the sleep mode (i.e., preparation processing for power OFF). When the engine control unit 140 of the engine unit 126 receives this instruction via the engine communication unit 133 of the controller unit 125, it executes power-off preparation processing for transitioning to the sleep mode, and when the power-off preparation processing is completed, it notifies the controller unit 125 of the completion of the power-off preparation processing.

[0074] After instructing the engine unit 126 to transition to the sleep mode, the state management unit 134 of the controller unit 125 instructs the system control unit 130 of the controller unit 125 to execute power-off preparation processing for transitioning to the sleep mode in the following step SP28. Upon receiving this instruction, the system control unit 130 executes the power-off preparation processing, and upon completion of the power-off preparation processing, notifies the state management unit 134 of the completion of the power-off preparation processing.

[0075] After the state management unit 134 issues an instruction to the system control unit 130 to execute power-off preparation processing to transition to sleep mode, in the following step SP29, it sets the controller state to sleep mode, and in the following step SP30, it stores the controller state in non-volatile memory 136.

[0076] In the next step SP31, the state management unit 134 waits for notification of the end of the power-off preparation process from both the engine control unit 140 and the system control unit 130, and when notification is received from both, the state management unit 134 proceeds to step SP32. In step SP32, the state management unit 134 issues an instruction to the power-saving operation unit 122 to power off the control unit 120.

[0077] When power-saving operation unit 122 receives an instruction from controller unit 125 to power off control unit 120, it issues an instruction to power supply unit 123 to power off control unit 120. This causes power to be turned off for control unit 120, and image forming apparatus 100 enters sleep mode. After issuing an instruction to power supply unit 123 to power off control unit 120 and transitioning to sleep mode, power-saving operation unit 122 starts monitoring I / F unit 121 in place of controller unit 125. The above is the operational procedure from when image forming apparatus 100 is powered on until it transitions to sleep mode.

[0078] Next, an operation procedure when the image forming apparatus 100 returns from the sleep mode will be described with reference to FIGS.

[0079] In the sleep mode, the power-saving operation unit 122, which monitors data reception by the I / F unit 121, issues an instruction to the power supply unit 123 to turn on the power supply of the control unit 120 if the data received via the I / F unit 121 is data that the power supply unit 122 cannot process itself. This causes power to be supplied to the control unit 120, and the startup process shown in FIG. 7 is started.

[0080] At this time, if the power-saving operation unit 122 receives data that it cannot process itself and that does not involve printing, it stores the received data and startup information indicating that the current startup does not involve printing in a memory (not shown) that is accessible from both the power-saving operation unit 122 and the controller unit 125.

[0081] Specifically, the power saving operation unit 122 has, for example, a non-volatile memory (not shown), and this non-volatile memory stores and holds a list P1 of protocols involving printing that the unit cannot process itself, and a list P2 of protocols that the unit cannot process itself and do not involve printing, as shown in Figures 10(A) and (B).

[0082] List P1 includes protocols that the power-saving operation unit 122 cannot process by itself and involve printing, such as Line Printer Remote protocol (LPR), Port9100, Internet Printing Protocol (IPP), NetBIOS over TCP / IP (NBT), etc. List P2 includes protocols that the power-saving operation unit 122 cannot process by itself and do not involve printing, such as Simple Network Management Protocol (SNMP), Domain Name System (DNS), Simple Network Time Protocol (SNTP), Teletype Network (Telnet), etc.

[0083] Incidentally, in list P1, LPR is a protocol for network printing, Port9100 is a simple protocol used for printing, IPP is a protocol for exchanging print data etc. between a printer in a remote location and a computer, and NBT is a protocol that allows NetBIOS to be used over TCP / IP.

[0084] Also included in list P2, SNMP is a protocol for monitoring and controlling devices on a network, DNS is a protocol used to manage the correspondence between domain names on the Internet and IP addresses, SNTP is a time synchronization protocol, and Telnet is a protocol for operating servers, routers, etc. in remote locations.

[0085] The power saving operation unit 122 identifies the protocol used for transmitting and receiving data from the data received via the I / F unit 121, and if the protocol is included in list P1, determines that the received data is data involving printing that the unit cannot process, and if the protocol is included in list P2, determines that the received data is data that the unit cannot process and does not involve printing.

[0086] In other words, when the protocol of the received data is included in list P2, the power-saving operation unit 122 stores the received data and startup information indicating that the current startup does not involve printing in a memory (not shown) accessible from both the power-saving operation unit 122 and the controller unit 125.

[0087] When the start-up process is started, the state management section 134 of the controller section 125 reads the controller state from the non-volatile memory 136 in the first step SP1 shown in Fig. 7. Since the current start-up is a start-up after returning from the sleep mode, the non-volatile memory 136 stores the controller state indicating the sleep mode.

[0088] In the next step SP2, the state management unit 134 obtains a positive result in step SP2 because the controller state indicating the sleep mode is stored in the non-volatile memory 136, and proceeds to step SP3. In other words, since the current startup is a startup after returning from the sleep mode, the state management unit 134 proceeds to step SP3.

[0089] In step SP3, the state management unit 134 deletes the controller state stored in the non-volatile memory 136. In the following step SP4, the state management unit 134 determines whether the current startup is a startup accompanied by printing. Specifically, the state management unit 134 determines whether the current startup is a startup accompanied by printing based on the startup information stored in the memory by the power-saving operation unit 122. That is, when startup information indicating that the current startup is a startup not accompanied by printing is stored in the memory, the state management unit 134 determines that the current startup is a startup not accompanied by printing, and otherwise determines that the current startup is a startup accompanied by printing.

[0090] If it is determined that the current startup is associated with printing, the state management unit 134 obtains a positive result in step SP4 and proceeds to step SP6. The operational procedure from step SP6 onwards has been described above, so a description thereof will be omitted.

[0091] On the other hand, if it is determined that the current startup does not involve printing, the state management unit 134 obtains a negative result in step SP4 and proceeds to step SP5. In step SP5, the state management unit 134 sets the controller state to sleep mode, and proceeds to step SP18 shown in Fig. 8. Note that here, the controller state is simply set to sleep mode to indicate that the previous operating mode was sleep mode, and the controller unit 125 is not actually powered off to enter sleep mode.

[0092] In step SP18, the state management unit 134 judges whether the current controller state is the standby mode or the sleep mode. Here, since the controller state was set to the sleep mode in step SP4, the state management unit 134 judges that the controller state is the sleep mode and proceeds to step SP33.

[0093] In step SP33, since the current startup is a return from sleep mode and does not involve printing, the state management unit 134 instructs the engine unit 126 to transition to the power saving mode. When the engine control unit 140 of the engine unit 126 receives this instruction via the engine communication unit 133 of the controller unit 125, it instructs the fixing control unit 143 to turn off the heating of the fixing unit 111, and transitions the engine unit 126 to the power saving mode. Therefore, at this time, the heating of the fixing unit 111 is not performed.

[0094] In the next step SP34, the state management unit 134 sets the controller state to the power saving mode, and puts the controller unit 125 into the power saving mode. Then, in step SP35, the state management unit 134 waits until the processing of the currently received data (i.e., processing not involving printing) is completed, and when completed, proceeds to step SP27 shown in Fig. 9. The operational procedure from step SP27 onwards has been described above, so a description thereof will be omitted. The operational procedure when the image forming apparatus 100 returns from the sleep mode is as described above.

[0095] [5. Summary and Effects] As described above, the image forming apparatus 100 of the present embodiment is capable of transitioning between an operating state (operating mode and standby mode), a first power saving state (power saving mode) which consumes less power than the operating state, and a second power saving state (sleep mode) which consumes less power than the first power saving state, and is provided with a fixing unit 111 which fixes a toner image transferred onto a printing medium onto the printing medium, a fixing control unit 143 which controls the fixing unit 111, and a state management unit 134 which, upon transition to the first power saving state (power saving mode), instructs the fixing control unit 143 not to heat the fixing unit 111 if the state before the transition is the second power saving state (sleep mode) (and the power saving mode is set to "low temperature control"), and instructs the fixing control unit 143 to heat the fixing unit 111 if the state before the transition is not the second power saving state (sleep mode).

[0096] In this way, when the state before the transition to the first power saving state (power saving mode) is the second power saving state (sleep mode), the fixing unit 111 is not heated. In other words, even when the state before the transition to the first power saving state (power saving mode) is entered, the fixing unit 111 is not necessarily heated, but is heated or not heated depending on the state before the transition.

[0097] In this way, in image forming apparatus 100, power consumption can be reduced compared to a case where fixing unit 111 is always heated upon transition to a predetermined state (for example, the first power saving state).

[0098] Here, in order to clarify the effect of this embodiment, for comparison, a timing chart in which the fixing unit 111 is heated when the power saving mode is switched to "low temperature control" regardless of the previous state is shown in Fig. 11. Note that the timing chart shown in Fig. 11 is a timing chart in the case where the power saving mode is set to "low temperature control".

[0099] 11, the image forming apparatus 100 goes into the sleep mode at time t23, and returns from the sleep mode to the power saving mode at time t24. At this time, although the previous operating mode is the sleep mode, the fixing unit 111 is heated to the standby temperature (low) according to the setting for the power saving mode ("low temperature control").

[0100] In contrast, in this embodiment, as shown in FIG. 6, the sleep mode is entered at time t13, and the sleep mode is returned to the power saving mode at time t14. At this time, since the previous operating mode is the sleep mode, the fixing unit 111 is not heated even though the setting in the power saving mode is "low temperature control."

[0101] It can also be seen from the timing charts shown in FIGS. 6 and 11 that image forming apparatus 100 of the present embodiment is able to reduce power consumption.

[0102] Furthermore, in the image forming apparatus 100 of this embodiment, if the data received by the I / F unit 121 as a receiving unit while in the second power saving state (sleep mode) is data that does not involve printing, the state management unit 134 transitions from the second power saving state (sleep mode) to the first power saving state (power saving mode).

[0103] That is, in the image forming apparatus 100, when the power-saving operation unit 122 operating in the second power-saving state (sleep mode) receives data via the I / F unit 121 that the power-saving operation unit 122 cannot process by itself and does not involve printing, the power-saving operation unit 122 activates the controller unit 125 and the engine unit 126 via the power supply unit 123, and the state management unit 134 of the controller unit 125 transitions from the second power-saving state (sleep mode) to the first power-saving state (power-saving mode). On the other hand, when the data received via the I / F unit 121 is data that the power-saving operation unit 122 cannot process and involves printing, the power-saving operation unit 122 activates the controller unit 125 and the engine unit 126 via the power supply unit 123, and the state management unit 134 transitions from the second power-saving state (sleep mode) to the operating state (operating mode).

[0104] In this manner, when the image forming apparatus 100 transitions from the second power saving state (sleep mode) to the first power saving state (power saving mode), since printing is not involved, power consumption can be reduced without heating the fixing unit 111, and when the image forming apparatus 100 transitions from the second power saving state (sleep mode) to the operating state (operating mode), since printing is involved, the fixing unit 111 is heated and printing can be started promptly.

[0105] [6. Other embodiments] [6-1. Another embodiment 1] In the above-described embodiment, the power-saving operation unit 122 operating in the sleep mode is configured to determine whether or not the data received via the I / F unit 121 is data that the unit cannot process itself and does not involve printing. However, the power-saving operation unit 122 may be configured to determine whether or not the data received via the I / F unit 121 is data that the unit can process itself, and the state management unit 134 of the controller unit 125 may determine whether or not the data received via the I / F unit 121 is data that does not involve printing when the unit returns (starts up) from the sleep mode.

[0106] [6-2. Other embodiment 2] In the above-described embodiment, the power-saving operation unit 122 determines whether the data is data that the power-saving operation unit 122 cannot process by itself and does not involve printing, based on the protocol of the data received via the I / F unit 121. However, the power-saving operation unit 122 may determine whether the data is data that the power-saving operation unit 122 cannot process by itself and does not involve printing, based on the size, type, commands included in the data, etc. Similarly, the state management unit 134 may determine whether the data is data that does not involve printing, based on the size, type, commands included in the received data, etc.

[0107] [6-3. Other embodiment 3] In the above-described embodiment, the present invention is applied to image forming device 100 that can transition between an operating mode and a standby mode as operating states, a power saving mode as a first power saving state that consumes less power than the operating state, and a sleep mode as a second power saving state that consumes less power than the first power saving state. However, the present invention is not limited to this, and can be applied to various image forming devices that can transition between an operating state, a first power saving state, and a second power saving state.

[0108] Furthermore, in each of the above-described embodiments, the present invention is applied to image forming apparatus 100 configured as a monochrome printer, but is not limited thereto, and can be applied to image forming apparatuses configured as color printers, and image forming apparatuses such as copiers, facsimiles, and multifunction machines (i.e., image forming apparatuses equipped with a fixing unit).

[0109] [6-4. Other embodiment 4] Furthermore, the present invention is not limited to the above-described embodiments, and the scope of application of the present invention extends to embodiments in which some or all of the above-described embodiments are combined in any manner, or in which some of the embodiments are extracted. [Industrial Applicability]

[0110] The present invention can be widely used in, for example, image forming apparatuses equipped with a fixing unit. [Explanation of symbols]

[0111] 100: image forming apparatus, 101: apparatus housing, 102: media cassette, 103: media stacker, 104-108: transport rollers, 109: image forming unit, 110: transfer unit, 111: fixing unit, 120: control unit, 121: I / F unit, 122: power saving operation unit, 123: power supply unit, 125: controller unit, 126: engine unit, 130: system control unit, 134: status management unit, 140: engine control unit, 143: fixing control unit, P: printing medium.

Claims

1. An image forming apparatus capable of shifting between an operating state, a first power saving state in which power consumption is lower than that of the operating state, and a second power saving state in which power consumption is lower than that of the first power saving state, a fixing section for fixing the toner image transferred onto the medium; A fixing control unit that controls the fixing unit; A receiving unit for receiving data; a state management unit that, when transitioning to the first power saving state, if a state before the transition is the second power saving state, instructs the fixing control unit not to heat the fixing unit, and, if a state before the transition is not the second power saving state, instructs the fixing control unit to heat the fixing unit; Equipped with When the data received by the receiving unit while in the second power saving state is data that does not involve printing, the state management unit transitions from the second power saving state to the first power saving state. The image forming apparatus according to claim 1,

2. An engine section for printing; a controller unit including the state management unit and controlling the engine unit; a power-saving operation unit that is activated when the device is in the second power-saving state; Equipped with When in the second power saving state, the receiving unit and the power saving operation unit are activated, When the data received by the receiving unit in the second power saving state is data that cannot be processed by the power saving operation unit, the controller unit and the engine unit are started, and when the data is data that does not involve printing, the state management unit transitions from the second power saving state to the first power saving state.

2. The image forming apparatus according to claim 1,

3. The power saving operation unit is It is determined whether the data received by the receiving unit while in the second power saving state is data that cannot be processed by the device itself and does not involve printing.

3. The image forming apparatus according to claim 2,

4. The power saving operation unit is determining whether the data received by the receiving unit while in the second power saving state is data that the device can process; The state management unit At the time of startup, it is determined whether the data is data that does not involve printing.

3. The image forming apparatus according to claim 2,

5. the first power saving state is a state in which the fixing unit is set to be heated to a predetermined temperature that is lower than that in the operating state; When the state management unit transitions to the first power saving state, if the state before the transition is the second power saving state, it instructs the fixing control unit not to heat the fixing unit, and when the state before the transition is not the second power saving state, it instructs the fixing control unit to heat the fixing unit to the predetermined temperature.

5. The image forming apparatus according to claim 1, wherein the image forming apparatus is a liquid crystal display.

6. When a predetermined time has elapsed since the operation performed in the operating state is completed, the state management unit transitions from the operating state to the first power saving state.

2. The image forming apparatus according to claim 1,

7. When the data received by the receiving unit while in the second power saving state is data involving printing, the state management unit transitions from the second power saving state to the operating state.

2. The image forming apparatus according to claim 1,

8. 1. A method for controlling an image forming apparatus capable of transitioning to an operating state, a first power saving state having lower power consumption than the operating state, and a second power saving state having lower power consumption than the first power saving state, comprising: When transitioning to the first power saving state, if the state before the transition is the second power saving state, a state management unit instructs a fixing control unit that controls a fixing unit that fixes a toner image transferred onto a medium onto the medium not to heat the fixing unit, and if the state before the transition is not the second power saving state, instructs the fixing control unit to heat the fixing unit; When data received by a receiving unit in the second power saving state is data that does not involve printing, the state management unit transitions from the second power saving state to the first power saving state. 2 is a control method for an image forming apparatus according to claim 1 .

Images