JP6862802B2 - Image forming device - Google Patents

Description

The present invention relates to an image forming apparatus.

Conventionally, when controlling heating of a plurality of resistance heat generating portions or the like, an image forming apparatus has been proposed that selects an energization pattern having the least overlap of energization periods from a plurality of energization patterns (see, for example, Patent Document 1). Further, an electronic device for shifting the phase of clocks supplied to a plurality of circuits for receiving data has also been proposed (see, for example, Patent Document 2).

Japanese Unexamined Patent Publication No. 2011-221106 Japanese Unexamined Patent Publication No. 2013-191932

However, the prior art described in Patent Document 1 does not reduce the power consumption as a whole including the members related to the control other than the heating control, although the permissible current at the time of energization is taken into consideration. Further, although the conventional technique described in Patent Document 2 shifts the current waveforms flowing through the plurality of circuits for data reception from each other, the power consumption is reduced as a whole including the circuits other than the plurality of circuits for data reception. It's not a thing. Therefore, since the maximum peak current value may increase due to the superposition of currents as a whole, it is necessary to have a circuit scale that matches the maximum peak current value. Therefore, there is a situation in which the cost of circuit components of the entire device increases.

The present disclosure has been made in view of such a situation, and makes it possible to reduce the cost of circuit components of the entire apparatus.

The image forming apparatus according to the first aspect of the present disclosure is an image forming apparatus including an image reading unit and an image forming unit and capable of communicating with an external device, and includes a power supply circuit for supplying power and the power supply. The state of the circuit, the control command regarding the image reading unit or the image forming unit, and the control unit that executes the control based on the control command are provided, and the control command is the execution timing of the external command arriving from the external device. It includes an adjustment instruction for adjusting the execution timing of an internal command issued at a fixed cycle at different timings, and the adjustment instruction is executed when at least a part of the power supply circuit has transitioned to the standby state. Is.

When at least a part of the power supply circuit is in the standby state, the image forming apparatus adjusts the execution timing of the internal command issued at a fixed cycle at a timing different from the execution timing of the external command arriving from the external device. To do. Therefore, since the peak of the current generated by the execution of the external command and the peak of the current generated by the execution of the internal command do not occur at the same time, there is no possibility that the peaks of the currents overlap each other. That is, the current consumption in the standby state is smoothed, so that the maximum peak current value decreases. Therefore, it is not necessary to use a circuit having a large maximum rated current that matches the maximum peak current value, so that the cost of circuit components of the entire device can be reduced.

Further , the power supply circuit further includes a volatile memory controlled at the execution timing of the internal command based on the operation reference clock, and an external interface controlled at the execution timing of the external command different from the operation reference clock. Is to supply power to the volatile memory based on the internal command, or to supply power to at least one of the image reading unit and the image forming unit based on the external command, and the adjustment instruction is the adjustment instruction. If the external interface is in operation, compared to the execution timing of the external command, Ru der those for delaying the execution timing of the internal command.

Further , a current detection unit that detects the current of the external interface and a storage unit that stores a current threshold used for determining the state of the external interface are further provided, and the control command is a detection result of the current detection unit. Further includes a determination instruction for determining the state of the external interface based on the current threshold value stored in the storage unit, and the adjustment instruction indicates that the state of the external interface is the operating state according to the determination instruction. When it is determined, the refresh timing of the volatile memory is delayed as the execution timing of the internal command, and the refresh timing of the volatile memory controls the execution timing of the refresh command of the volatile memory. Oh Ru.

Further, the current threshold value includes a first threshold value and a second threshold value larger than the first threshold value, and in the determination instruction, the detection result of the current detection unit sets the first threshold value and the second threshold value. If it exceeds, it is preferable that the current of the external interface tends to increase and the state of the external interface is determined to be in the operating state.

Further, the refresh command sends a load current to the volatile memory at a fixed cycle, and the adjustment instruction is from the issuance of the internal command to the flow of the load current to the volatile memory. In addition, when it is determined that the state of the external interface is in the operating state, it is preferable that the execution of the refresh command is suspended.

Further, it is preferable that the adjustment instruction delays the refresh timing according to the delay amount based on the request from the external interface.

According to the first aspect of the present disclosure, the cost of circuit components of the entire device can be reduced.

It is a figure which shows an example of the control structure formed on the substrate 17 of the image forming apparatus 1 in Embodiment 1 to which this disclosure is applied. It is a figure which intuitively explains the concept that the maximum rated current is suppressed in Embodiment 1. It is a figure which shows an example of the control structure formed on the substrate 17 of the image forming apparatus 1 in Embodiment 2. FIG. It is a figure which intuitively explains the concept of shifting a load current in Embodiment 2. It is a figure which intuitively explains the concept that the maximum rated current is suppressed in Embodiment 2. It is a figure which shows an example of the control structure formed on the substrate 17 of the image forming apparatus 1 in Embodiment 3. FIG. It is a figure which shows an example of the power supply system in Embodiment 3. It is a figure which shows an example of the state transition of the power supply circuit 31 in Embodiment 3. It is a timing chart which shows an example of the execution timing of the internal command in Embodiment 3. It is a figure explaining the change example of the current value of the external interface 41 in Embodiment 4. It is a timing chart which shows an example of the execution timing of an internal command in Embodiment 5. It is a figure which shows an example of the control structure formed on the substrate 17 of the image forming apparatus 1 in Embodiment 6. It is a timing chart which shows an example of the execution timing of the internal command in Embodiment 6.

Hereinafter, embodiments of the present disclosure will be described with reference to the drawings, but the present disclosure is not limited to the following embodiments.

Embodiment 1.
FIG. 1 is a diagram showing an example of a control configuration formed on the substrate 17 of the image forming apparatus 1 in the first embodiment to which the present disclosure is applied. FIG. 2 is a diagram that intuitively explains the concept of suppressing the maximum rated current in the first embodiment. The image forming apparatus 1 includes an image reading unit 11 and an image forming unit 13, and can communicate with the external device 15. The image reading unit 11 sequentially reads the documents sent by the automatic document feeding device by the image sensor. The image forming unit 13 includes an exposure device, a photosensitive drum, a developing device, a transfer belt, and a fixing device, and forms an image on paper based on the image data of the original document read by the image reading unit 11. The substrate 17 controls the image reading unit 11 and the image forming unit 13 by communicating with the external device 15 or the like. The board 17 includes a control unit 21, a power supply circuit 31, and the like. The power supply circuit 31 includes a current detection unit 31a and a power conversion unit 31b to supply electric power. The current detection unit 31a is realized by, for example, a Hall element or a shunt resistor, and detects the current of the external interface 41. The power conversion unit 31b converts commercial AC power into preset DC power.

The control unit 21 includes a ROM, a RAM, a CPU, and an I / O interface 21a. The control unit 21 realizes the functions of the determination unit 21b, the power management unit 21d, and the like when the CPU executes, for example, one or more programs. The control unit 21 includes a storage unit 21c, and the storage unit 21c is realized by a RAM or the like provided in the control unit 21. The I / O interface 21a is an interface for connecting the control unit 21 and peripheral devices. The determination unit 21b is a function of determining the state of the external interface 41 according to the determination instruction included in the control command. The storage unit 21c stores the current threshold value used for determining the state of the external interface 41. The power management unit 21d is a function that comprehensively manages the transition to the standby state, which is the energy saving mode.

The substrate 17 includes a volatile memory 23a and an external interface 41. The volatile memory 23a is controlled at the execution timing of an internal command based on the operation reference clock. The external interface 41 is controlled at an execution timing of an external command different from the operation reference clock. Since the external command arrives at random, it is preferable that the external command is detected by, for example, a detection clock having a period shorter than the operation reference clock. The power supply circuit 31 supplies electric power to the volatile memory 23a based on an internal command. The power supply circuit 31 supplies electric power to at least one of the image reading unit 11 and the image forming unit 13 based on an external command. The volatile memory 23a is, for example, a DRAM of DDR3, specifically DDR3-SDRAM. The external interface 41 includes, for example, a LAN interface 41a described later.

Specifically, when the image forming apparatus 1 is activated by the FAX function when the image forming apparatus 1 is in the standby state, the image forming apparatus 1 is required to be activated quickly in order to shift to the preparation for receiving the FAX reception data. Therefore, it is preferable that the image forming apparatus 1 is started quickly by using the program data stored in the volatile memory 23a. In the volatile memory 23a, each block in the chip is refreshed at a fixed cycle based on the operation reference clock as described above in order to hold the program data. Therefore, the refresh timing of the volatile memory 23a can be controlled. On the other hand, the external interface 41 may temporarily consume current due to access to the MAC address storage table by ping and its response processing in order to confirm the network connection. In the ping cycle, a plurality of terminals and the like connected as the external device 15 transmit packets at various timings. Therefore, since external commands such as ping and the like arrive at random as described above, they arrive from the external device 15 at an uncontrollable timing.

Therefore, conventionally, the maximum rated current may increase due to the overlap of the response processing by the external interface 41 and the refresh timing of the volatile memory 23a. Therefore, in the present disclosure, as shown in FIGS. 1 and 2, the maximum rated current is smoothed by monitoring the current of the external interface 41 and shifting the phase of the refresh command, and the increase in the maximum rated current is suppressed. There is. Specifically, the control unit 21 executes control based on the state of the power supply circuit 31 and the control command regarding the image reading unit 11 or the image forming unit 13. The control command includes an adjustment instruction for adjusting the execution timing of the internal command issued at a fixed cycle at a timing different from the execution timing of the external command arriving from the external device 15. The adjustment instruction is executed when at least a part of the power supply circuit 31 has transitioned to the standby state.

In other words, when at least a part of the power supply circuit 31 is in the standby state, the image forming apparatus 1 is issued at a fixed cycle at a timing different from the execution timing of the external command coming from the external device 15. Adjust the execution timing of internal commands. Therefore, since the peak of the current generated by the execution of the external command and the peak of the current generated by the execution of the internal command do not occur at the same time, there is no possibility that the peaks of the currents overlap each other. That is, the current consumption in the standby state is smoothed, so that the maximum peak current value decreases. Therefore, it is not necessary to use a circuit having a large maximum rated current that matches the maximum peak current value, so that the cost of circuit components of the entire device can be reduced.

Embodiment 2.
As described above, the LAN interface 41a of the second embodiment is included in the external interface 41 of the first embodiment. In the second embodiment, the adjustment instruction of the first embodiment will be described more specifically. FIG. 3 is a diagram showing an example of a control configuration formed on the substrate 17 of the image forming apparatus 1 in the second embodiment. FIG. 4 is a diagram that intuitively explains the concept of shifting the load current in the second embodiment. FIG. 5 is a diagram that intuitively explains the concept of suppressing the maximum rated current in the second embodiment.

When at least a part of the power supply circuit 31 transitions to the standby state and the external interface 41 is in the operating state, the adjustment instruction executed by the control unit 21 of FIG. 3 is an internal command as compared with the execution timing of the external command. It delays the execution timing. Therefore, as shown in FIGS. 4 and 5, the phase of the instantaneous current peak value generated in the volatile memory 23a and the phase of the instantaneous current peak value generated in at least one of the image reading unit 11 and the image forming unit 13 Therefore, the peak of the current consumption of the volatile memory 23a and the peak of the current consumption of the external interface 41 do not overlap. Therefore, the current consumption of the entire device can be smoothed, and the efficiency of the entire device can be improved.

Embodiment 3.
In the third embodiment, the adjustment instruction of the first embodiment and the determination instruction of the second embodiment will be described more specifically. FIG. 6 is a diagram showing an example of a control configuration formed on the substrate 17 of the image forming apparatus 1 in the third embodiment. FIG. 7 is a diagram showing an example of the power supply system according to the third embodiment. As shown in FIG. 7, the power conversion unit 31b includes an AC / DC conversion unit 311, a DC / DC conversion unit 312a, a DC / DC conversion unit 312b, and a DC / DC conversion unit 313. The AC / DC conversion unit 311 converts a commercial AC power supply into a DC power supply. The DC power converted by the AC / DC conversion unit 311 is used for standby state control or operating state control. When used for standby state control, it is used for first standby state control or second standby state control. The DC / DC conversion unit 312a converts the DC power converted by the AC / DC conversion unit 311 into DC power suitable for the first standby state control. The load on which the first standby state control is performed is, for example, the volatile memory 23a. The DC / DC conversion unit 312b converts the DC power converted by the AC / DC conversion unit 311 into DC power suitable for the second standby state control. The load on which the second standby state control is performed is, for example, the image reading unit 11 used when copying. On the other hand, the DC / DC conversion unit 313 converts the DC power converted by the AC / DC conversion unit 311 into DC power suitable for operating state control. The load for which the operation state control is performed is, for example, the external interface 41. FIG. 8 is a diagram showing an example of the state transition of the power supply circuit 31 in the third embodiment. As shown in FIG. 8, the power supply circuit 31 has transition states of T04, which is a cutoff state in which the power is turned off, T03, which is a second standby state, T02, which is a first standby state, and T01, which is an operating state. Yes, in the energy saving mode, the state of the power supply circuit 31 transitions to T02 or T03.

FIG. 9 is a timing chart showing an example of the execution timing of the internal command in the third embodiment. In one example of FIG. 9, by delaying the internal command by the delay interval t, the load current of the volatile memory 23a is generated after the load current of the external interface 41 is generated. That is, if it is determined that the state of the external interface 41 is the operating state based on the load current of the external interface 41 detected by the current detection unit 31a, the refresh of the volatile memory 23a is delayed by delaying the internal command. Let me.

Specifically, the determination instruction executed by the control unit 21 causes the state of the external interface 41 to be determined based on the detection result of the current detection unit 31a and the current threshold value stored in the storage unit 21c. .. Therefore, when the image forming apparatus 1 determines that the state of the external interface 41 is the operating state based on the current detection result of the external interface 41 and the current threshold value, as shown in FIG. The refresh timing of the volatile memory 23a is delayed as the execution timing. Therefore, since the timing of the response processing of the external command arriving at the external interface 41 and the refresh timing of the volatile memory 23a do not overlap, the maximum rated current is smoothed. Therefore, the efficiency can be improved while suppressing the cost of the power supply circuit 31. The refresh timing of the volatile memory 23a controls the execution timing of the refresh command of the volatile memory 23a.

Embodiment 4.
The fourth embodiment more specifically describes the current threshold value of the second embodiment. FIG. 10 is a diagram illustrating an example of a change in the current value of the external interface 41 in the fourth embodiment. As shown in FIG. 10, the current threshold includes a first threshold and a second threshold. The second threshold value is set to a value larger than the first threshold value. In the pattern A, the current value of the external interface 41 exceeds the first threshold value and the second threshold value. That is, in the pattern A, since the current value of the external interface 41 tends to increase and the external interface 41 is in the operating state, the internal command is delayed and controlled. On the other hand, in the pattern B, the current value of the external interface 41 is lower than the second threshold value. That is, in the pattern B, since the current value of the external interface 41 tends to decrease, the delay control of the internal command is released.

Specifically, in the image forming apparatus 1, when the current detection result of the external interface 41 exceeds the first threshold value and the second threshold value, the current of the external interface 41 tends to increase and the state of the external interface 41 is changed. Judge that it is in the operating state. That is, by setting the current threshold value in two stages, it is determined whether or not the current of the external interface 41 may reach the peak value instantaneously. Therefore, since the state of the external interface 41 can be accurately assumed, the internal command can be delayed at an appropriate timing.

Embodiment 5.
In the fifth embodiment, the adjustment instructions of the first to third embodiments will be described more specifically. FIG. 11 is a timing chart showing an example of the execution timing of the internal command in the fifth embodiment. As shown in FIG. 11, when the load current of the external interface 41 is generated after the internal command is issued, the load current of the volatile memory 23a is delayed and controlled by the control stop command. Specifically, when the image forming apparatus 1 determines that the state of the external interface 41 is in the operating state between the time when the internal command is issued and the time when the load current flows through the volatile memory 23a, the refresh command is used. Pause execution. That is, when an external command arrives at an uncontrollable timing, the response corresponding to the controllable internal command is postponed. Therefore, when the external command is executed, the phase of the refresh command can be reliably shifted by not executing the refresh command with the control stop command.

Embodiment 6.
In the sixth embodiment, the adjustment instructions of the first to third and fifth embodiments will be described more specifically. FIG. 12 is a diagram showing an example of a control configuration formed on the substrate 17 of the image forming apparatus 1 according to the sixth embodiment. In one example of FIG. 12, in addition to the volatile memory 23a, the non-volatile memory 23b is mounted on the substrate 17. The non-volatile memory 23b is controlled by the memory control unit 21e, which is one of a plurality of functions realized by the control unit 21. When the volatile memory 23a and the non-volatile memory 23b are generically referred to, they are referred to as a semiconductor memory 23. The external interface 41 includes a telephone line interface 41b and a USB interface 41c in addition to the LAN interface 41a. A print JOB arrives at the LAN interface 41a as an external command. The telephone line interface 41b receives fax reception data as an external command. In the USB interface 41c, various data arrive from the mounted device.

FIG. 13 is a timing chart showing an example of the execution timing of the internal command in the sixth embodiment. In an example of FIG. 13, when a request is made from the external interface 41 to the control unit 21, the load current of the volatile memory 23a is delayed. Specifically, the image forming apparatus 1 delays the refresh timing according to the amount of delay based on the request from the external interface 41. Therefore, by appropriately setting the delay amount, the refresh timing can be set at an arbitrary execution timing. In one example of FIG. 13, the request from the external interface 41 is realized by a square wave. Further, the volatile memory 23a is set to be refreshed when the square wave rises. Therefore, the amount of delay can be controlled by controlling this rectangular wave.

Although the image forming apparatus 1 which is one aspect of the present disclosure has been described above based on the embodiment, the present disclosure is not limited to this, and changes may be made without departing from the gist of the present disclosure. Good. For example, an example in which the volatile memory 23a is a RAM of DDR3 has been described, but the present invention is not particularly limited thereto. For example, the volatile memory 23a may be a DDR4 RAM. Further, for example, an example in which a rectangular wave is used as an example of controlling the delay amount has been described, but the present invention is not particularly limited to this. For example, various waveforms such as a sine wave, a triangular wave, and a sawtooth wave are possible.

As described above, the control command is one or more programs. That is, one or more programs include an adjustment instruction for adjusting the execution timing of the internal command issued at a fixed cycle at a timing different from the execution timing of the external command coming from the external device 15, and detection by the current detection unit 31a. It includes a determination instruction for determining the state of the external interface 41 based on the result, the current threshold value stored in the storage unit 21c, and the determination instruction.

1 image forming device, 11 image reading unit, 13 image forming unit, 15 external device,
17 board, 21 control unit, 21a I / O interface, 21b judgment unit,
21c storage unit, 21d power management unit, 21e memory control unit,
23 Semiconductor memory, 23a volatile memory, 23b non-volatile memory,
31 power supply circuit, 31a current detector, 31b power converter,
311 AC / DC converter,
312a, 312b, 313 DC / DC converter,
41 external interface, 41a LAN interface,
41b telephone line interface, 41c USB interface,
A, B pattern, t delay interval

Claims (4)

An image forming apparatus having an image reading unit and an image forming unit and capable of communicating with an external device.
Power supply circuit that supplies power and
A control unit that executes control based on the state of the power supply circuit and a control command regarding the image reading unit or the image forming unit.
Volatile memory controlled by the execution timing of internal commands based on the operation reference clock,
An external interface controlled by the execution timing of an external command different from the operation reference clock,
A current detector that detects the current of the external interface and
A storage unit that stores the current threshold value used for determining the state of the external interface, and a storage unit.
With
The power supply circuit
Powering or powering the volatile memory based on the internal command
Power is supplied to at least one of the image reading unit and the image forming unit based on the external command.
The control command is
Wherein the timing different from the execution timing of the external command coming from the external device, adjustment instruction for adjusting the execution timing of the internal commands issued at a predetermined period,
A determination instruction for determining the state of the external interface based on the detection result of the current detection unit and the current threshold value stored in the storage unit.
Including
The adjustment instruction is
All SANYO at least a part of the power supply circuit is performed when the transition of the standby state,
When the state of the external interface is determined to be the operating state by the determination instruction, the refresh timing of the volatile memory is delayed as the execution timing of the internal command as compared with the execution timing of the external command.
The refresh timing of the volatile memory is
It controls the execution timing of the volatile memory refresh command.
Image forming device. The current threshold is
The first threshold and
A second threshold value larger than the first threshold value and
Including
The judgment instruction is
When the detection result of the current detection unit exceeds the first threshold value and the second threshold value, it is determined that the current of the external interface tends to increase and the state of the external interface is in the operating state. ,
The image forming apparatus according to claim 1. The refresh command is
A load current is passed through the volatile memory at regular intervals.
The adjustment instruction is
When it is determined that the state of the external interface is in the operating state between the time when the internal command is issued and the time when the load current flows through the volatile memory, the execution of the refresh command is suspended. is there,
The image forming apparatus according to claim 1 or 2. The adjustment instruction is
The refresh timing is delayed according to the amount of delay based on the request from the external interface.
The image forming apparatus according to any one of claims 1 to 3.

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