JP2019132932A - Image forming apparatus and method for calculating power consumption - Google Patents

Abstract

To calculate power consumption not deviating from the actual power consumption regardless of the change of the degree of temperature rise of a fixing unit or a print condition.SOLUTION: An image forming apparatus of the present invention comprises a fixing unit 20 that has a halogen heater 21 for thermally fixing an image formed on a transfer sheet, and a timer 44 that measures the time of heating performed by the halogen heater 21 at a predetermined interval. The image forming apparatus has power consumption value calculation means 41a that calculates the power consumption value of the halogen heater 21 on the basis of information on the power consumption of the halogen heater 21 that is sequentially updated with the lapse of the heating time; and power consumption calculation means 41b that calculates the power consumption of the halogen heater 21 on the basis of the calculated power consumption value and the heating time.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an image forming apparatus and a power consumption calculation method.

  Conventionally, there is a configuration disclosed in Patent Documents 1 and 2 as this type of image forming apparatus. FIG. 10 is an explanatory diagram illustrating calculation of the power consumption of the image forming apparatus disclosed in Patent Document 1. In FIG. 10, the vertical axis shown in the upper part shows ON / OFF of the fixing control, the vertical axis shown in the lower part shows the power consumption value, and the horizontal axis shows time. FIG. 10 shows an example in which the power consumption is calculated by multiplying the fixed value of 550 W by the ON time of the control signal.

In the image forming apparatus disclosed in Patent Document 1, power consumption values in each operation mode of a fixing heater and a DC (Direct Current) unit are stored, and an energization on time is measured by a CPU (Central Processing Unit). doing. Then, the power consumption amount in the AC (Alternating Current) section is calculated by multiplying the measured power-on time by the power consumption value of the fixing heater.
In addition, the result of transition time measurement in each operation mode such as printing conditions and the power consumption value in the DC unit according to the power consumption value of each operation mode in the DC unit are added together to calculate the power consumption of the entire apparatus by adding these two calculation results. Calculated.

On the other hand, the image forming apparatus disclosed in Patent Document 2 does not store the power consumption value of each operation mode of the fixing heater and the DC unit, but the power consumption value in a transient state immediately after the operation is started and immediately before the operation is stopped. The power consumption amount of the fixing heater is calculated from the input power value and the energization time while correcting the power consumption amount based on the change in the power consumption.
By the way, in the image forming apparatus, when the printing conditions such as color, monochrome, thin paper / thick paper are different, the power consumption value of the fixing unit is different. FIG. 11 is a diagram illustrating a change over time in the power consumption value in a fixing unit of a general image forming apparatus, where the vertical axis indicates the power consumption value and the horizontal axis indicates the elapsed time.

  In FIG. 11, what is indicated by (A) is the power consumption value in the fixing unit during monochrome printing, and this average power consumption value is 583W. Also, what is indicated by (A) is the power consumption value at the time of color printing, and this average power consumption value is 660 W. That is, it is clear that the power consumption value varies depending on the printing conditions.

  However, since each of the image forming apparatuses described in Patent Documents 1 and 2 uses a predetermined value as the power consumption value of the fixing unit, the power consumption value varies depending on the temperature rise of the fixing unit and the printing conditions. It does not consider the point where For this reason, the problem that the power consumption to be calculated deviates from the actual power consumption remains unsolved.

  Further, although the power consumption value of the fixing unit is stabilized with time as the temperature rises, conventionally, the power consumption value of the fixing unit that varies depending on various conditions is not taken into consideration. Further, in the image forming apparatus described in Patent Document 2, since the power consumption is calculated while correcting the power consumption value during the printing period, the number of software processing steps increases, and information for correction is held. Therefore, the storage capacity occupied in the ROM has increased.

  SUMMARY An advantage of some aspects of the invention is that it provides an image forming apparatus capable of calculating a power consumption amount that does not deviate from an actual power consumption amount regardless of a temperature rise of a fixing unit or a change in printing conditions.

  In order to solve the above problems, the present invention includes a fixing unit having a heating unit for heating and fixing an image formed on a medium, and a heating time measuring unit that measures a heating time by the heating unit at a predetermined interval. A power consumption value calculating unit that calculates a power consumption value of the heating unit based on power consumption information of the heating unit that is sequentially updated as the heating time elapses, and a heating unit that is sequentially updated. Power consumption value calculation means for calculating the power consumption value of the heating means based on the power consumption information of the heating means, power consumption value of the heating means based on the power consumption value calculated by the power consumption value calculation means and the heating time Power consumption calculating means for calculating the amount.

  According to the present invention, it is possible to calculate a power consumption amount that does not deviate from the actual power consumption amount regardless of the degree of temperature rise of the fixing unit or a change in printing conditions.

1 is a cross-sectional view illustrating a schematic configuration of an image forming apparatus according to an embodiment of the present invention. 2 is a block diagram illustrating a power supply circuit of a digital multi-function peripheral according to an example of the image forming apparatus according to the embodiment. FIG. It is a flowchart which shows the 1st example of the processing content which calculates electric power consumption from the heating electric power value calculated | required using the heater lighting ratio (lighting duty) with progress of heating time, and heating time. It is a figure which shows the effect obtained with the digital multifunctional device which concerns on an example same as the above. It is the figure which calculated the power consumption when three sheets of color printing were performed with the prior art, this invention, and the actual machine measured value, and showed the effect of this invention quantitatively. It is a flowchart which shows the 2nd example of the processing content which calculates power consumption from the power consumption value and heating time which were calculated | required using the heater lighting ratio (lighting duty) accompanying progress of heating time. It is a flowchart which shows the 3rd example of the processing content which calculates power consumption from the heating electric power value calculated | required using the heater lighting ratio (lighting duty) with progress of heating time, and heating time. It is a flowchart which shows the 4th example of the processing content which calculates electric energy consumption from the heating electric power value calculated | required using the heater lighting ratio (lighting duty) with progress of heating time, and heating time. It is a flowchart which shows the 5th example of the processing content which calculates electric energy consumption from the heating electric power value calculated | required using the heater lighting ratio (lighting duty) with progress of heating time, and heating time. 10 is an explanatory diagram illustrating calculation of power consumption of the image forming apparatus disclosed in Patent Literature 1. FIG. FIG. 7 is a diagram illustrating a change with time of a power consumption value in a fixing unit of a general image forming apparatus.

  Hereinafter, an image forming apparatus according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view showing a schematic configuration of an image forming apparatus according to an embodiment of the present invention. In the present embodiment, a digital multifunction machine having a copying function, a printer function, a facsimile function, and the like will be described as an example of an image forming apparatus.

  The digital multifunction peripheral A according to an example has a configuration in which an operation unit 10, an automatic document feeder 11, an image reading device 12, a writing unit 13, and a printer unit 14 are arranged in multiple upper and lower stages.

The operation unit 10 is provided with an application switching key (not shown) for sequentially switching and selecting a copying function, a printer function, and a facsimile function.
That is, by selecting a copy function, a printer function, and a facsimile function by operating an application switching key, a copy mode, a printer mode, and a facsimile mode are set, respectively.

The automatic document feeder 11 is for sequentially feeding a bundle of documents to the image reading device 12.
The image reading device 12 is for reading image information of a document fed from the automatic document feeder 11.
The writing unit 13 is for converting image information read by the image reading device 12 into optical information.

The printer unit 14 includes a developing device 15, a photosensitive drum 16, a conveyance belt 17, and a fixing unit 20.
The photosensitive drum 16 is for forming an electrostatic latent image by being uniformly charged by a charger (not shown) and then exposed by the optical information from the writing unit 13.
The developing device 15 is for developing the formed electrostatic latent image into a toner image.
The conveyor belt 17 is disposed below the photosensitive drum 16 and is for transferring the developed toner image onto a transfer sheet (not shown) as a medium.

  The fixing unit 20 has a heating unit for heating and fixing an image formed on the transfer paper, and fixes the toner image transferred to the transfer paper by the heating unit. In the present embodiment, the halogen heater 21 (shown in FIG. 2) is exemplified as the heating means, but is not limited thereto.

A series of operations in the copying mode of the digital multi-function peripheral A having the above configuration will be described with reference to FIG.
In the copy mode, the document bundle is sequentially fed to the image reading device 12 by the automatic document feeder 11 and then image information is read by the image reading device 12.

The read image information is converted into optical information by the writing unit 13, and the photosensitive drum 16 is uniformly charged by a charger (not shown) and then exposed by the optical information from the writing unit 13. An electrostatic latent image is formed.
The electrostatic latent image on the photosensitive drum 16 is developed by the developing device 15 to become a toner image. The toner image is transferred onto the transfer paper by the transport belt 17, and the transfer paper on which the toner image is transferred is discharged and transported outside the apparatus after the toner image is fixed by the fixing device 20.

FIG. 2 is a block diagram showing a power supply circuit of the digital multi-function peripheral A shown in FIG.
The power supply circuit shown in FIG. 2 includes a display unit 30, a control board 40, and a PSU (power supply unit) 50, and the fixing unit 20 described above is included in the fixing control circuit 52 that forms part of the PSU 50. Is connected.

The control board 40 has a central processing unit (CPU) 41 serving as a control center of the apparatus, a read only memory (ROM) 42 and a random access memory (RAM) 43 serving as a storage unit.
The PSU 50 includes a voltage detection circuit 51 and a fixing control circuit 52, and an AC-DC converter 53 and a DC-DC converter 54 are connected in series between the voltage detection circuit 51 and the control board 40. ing.

  The voltage detection circuit 51 is for detecting the voltage value of the power supply 55 in the power supply environment, the current consumption value and the power consumption value of the machine A during operation. The detected power supply voltage value, current consumption value, and power consumption value are A / D converted by the CPU 41 and stored in the ROM 42 and RAM 43 as information.

The ROM 42 and RAM 43 store information such as the heater lighting ratio (lighting duty) of the halogen heater 21 and the heating time, which are used for calculating the power consumption, in addition to the detected voltage value. The heating time is counted by the timer 44.
In the present embodiment, the timer 44 is a heating time measuring unit that measures the heating time by the halogen heater (heating means) 21 at a predetermined interval.

The fixing control circuit 52 is connected to the fixing unit 20 and controls to switch energization / non-energization to the fixing unit 20 in accordance with an output signal from the CPU 41.
CPU41 implement | achieves the following function by execution of the required program memorize | stored in the memory | storage part.

(1) A function of calculating the power consumption value in the halogen heater 21 based on the power consumption information of the halogen heater 21 that is sequentially updated as the heating time by the halogen heater 21 serving as a heating means elapses. This function is referred to as “power consumption value calculation means 41a”.
“Elapsed heating time” means “real time” and is synonymous with “real time”.
The “power consumption information” includes the heater lighting ratio (lighting duty) of the halogen heater 21, the heating time, the temperature target, the power target, the detection voltage value stored in the ROM 42 and the RAM 43, and the like.

(2) A function of calculating the power consumption amount of the halogen heater 21 based on the power consumption value calculated by the power consumption value calculation means 41a and the heating time. This function is referred to as “power consumption calculation means 41b”.

In the present embodiment, the power consumption amount of the halogen heater 21 is calculated based on the above-described power consumption information, and the calculation result is stored in the ROM 42 and the RAM 43. The calculation result is also displayed on the display unit 30 in accordance with a user operation.
In other words, the power consumption information of the fixing unit 20 is calculated by using the power consumption information such as the temperature rise of the fixing unit 20 and the heater lighting ratio that changes depending on the printing conditions such as monochrome and thin color paper / thick paper. The amount of power is derived.

FIG. 3 is a flowchart showing a first example of processing content for calculating the power consumption amount from the power consumption value obtained by using the heater lighting ratio (lighting duty) with the elapse of the heating time and the heating time.
The power consumption calculation method used for the image forming apparatus having the above-described configuration is as follows.
Based on the power consumption information of the halogen heater 21 that is sequentially updated as the heating time elapses, the power consumption value of the halogen heater 21 is calculated, and the halogen heater 21 of the halogen heater 21 is calculated based on the calculated power consumption value and the heating time. It is characterized by calculating power consumption. The details are shown below.

Step (abbreviated as “S1” in the figure. The same applies hereinafter) 1: Acquisition of lighting duty log is started.
Step 2: The acquisition start time (T ₁ ) of the lighting duty log is stored in the storage unit.
Step 3: Set the number of times to store the lighting duty log (K = 0).
Step 4: Store the lighting duty log (D _x ).
Step 5: Count up the number of times the lighting duty log is stored (K _x = K + 1).

Step 6: It is determined whether or not the lighting duty log is end. When it is determined that the lighting duty log is end, the process returns to step 4;
Step 7: The acquisition completion time (T ₂ ) of the lighting duty log is stored, and the process proceeds to Step 8.
Step 8: Calculate power consumption.
The power consumption in this example is calculated as follows.
[[Va ÷ Vb] ^1.54 * (Wa ÷ [D ₁ + D ₂ ... D _x ] ÷ K _x ) * Va] ÷ (T ₂ −T ₁ ) ÷ 3600

Va: Device rated voltage (stored in ROM 42 in advance, for example, 100 V)
Vb: Rated heater voltage (stored in ROM 42 in advance, for example, 97 V)
Wa: Heater W (previously stored in ROM 42, eg, 800 W)
D _x : lighting duty log K _x : lighting duty log storage count T ₁ : lighting duty log acquisition start time T ₂ : lighting duty log acquisition end time

  By such processing, it is possible to calculate a power consumption amount that does not deviate from the actual power consumption amount regardless of the temperature rise degree of the fixing unit 20 or a change in printing conditions.

FIG. 4 is a diagram illustrating the effect obtained by the digital multifunction peripheral A described above, in which the vertical axis indicates the power consumption value and the horizontal axis indicates the heating time.
In the region (c) shown in FIG. 4, the power consumption value changes greatly as the heating time elapses because the temperature of the fixing unit 20 is not stable. For this reason, in this digital multi-function peripheral A, the lighting duty is acquired in the area (c) in real time, and the power consumption is calculated from the power consumption value and the heating time using the acquired lighting duty.

FIG. 5 is a diagram that quantitatively shows the effect of the present invention by calculating the power consumption when three sheets of color printing are performed using the prior art, the present invention, and actual machine measurement values.
As shown in FIG. 5, the divergence between the prior art and the actual machine measurement value is 24.5 kwh, and the divergence between the present invention and the actual machine measurement value is 1.0 kwh, and the divergence increases as one month, one year, and month and day pass. It is clear.

  Power consumption that does not deviate from the actual power consumption by calculating the AC power consumption by the halogen heater 21 using the power consumption information of the heater lighting ratio (lighting duty) that changes according to the printing conditions and the information of various operation times. The amount can be calculated.

FIG. 6 is a flowchart showing a second example of processing contents for calculating the power consumption amount from the power consumption value obtained by using the heater lighting ratio (lighting duty) with the elapse of the heating time and the heating time.
In the case of this example, the CPU 41 realizes the following functions by executing a required program stored in the storage unit.

(3) A function for determining whether or not fluctuations in the power consumption value are stable (this function is referred to as “first power consumption determination unit 41 c”).
When the first power consumption determination unit 41c determines that the fluctuation in power consumption is stable, the power consumption amount calculation unit 41b uses the power consumption information acquired at the measurement interval of the heating time and the consumption calculated based on the heating time. Based on the power value, the power consumption of the heating means (halogen heater 21) is calculated.
Detailed processing contents are shown below.

Step (abbreviated as “SA1” in the figure. The same applies hereinafter) 1: Acquisition of lighting duty log is started.
Step 2: The acquisition start time (T ₁ ) of the lighting duty log is stored in the storage unit.
Step 3: Set the number of times to store the lighting duty log (K = 0).
Step 4: Store the lighting duty log (D _x ).
Step 5: Calculate the transition of the lighting duty log (Ds = D _x -D _x-1 ).

Step 6: It is determined whether or not the transition Ds> 5.0% of the lighting duty log. If Ds> 5.0%, the process proceeds to step 7; otherwise, the process proceeds to step 7a.
Step 7: Count up the number of times the lighting duty log is stored (K _x = K + 1).
Step 8: It is determined whether or not the lighting duty log is at the end. If it is determined that the lighting duty log is at the end, the process returns to step 4;

Step 7a: Since Ds> 5.0% is not satisfied in Step 6, the storage time (T ₃ ) of the lighting duty log with Ds ≦ 5.0% is stored.
Step 8a: The lighting duty log (U _x ) is stored.
Step 9a: Count up the number of times the lighting duty log is stored (Ly = L + 1).

Step 10a: It is determined whether or not the lighting duty log is end. When it is determined that the lighting duty log is end, the process proceeds to step 12; otherwise, the process proceeds to step 11a.
Step 11a: It is determined whether or not the lighting duty log storage count Ly is a multiple of “5”. If it is a multiple of “5”, the process proceeds to Step 8a, and if not, the process returns to Step 9a.

Step 12: The acquisition completion time (T ₂ ) of the lighting duty log is stored, and the process proceeds to Step 13.
Step 13: Calculate power consumption.
The power consumption in this example is calculated as follows.
[[Va ÷ Vb] ^1.54 * (Wa ÷ [D ₁ + D ₂ ... D _x ] ÷ K _x ) * Va] ÷ (T ₂ −T ₁ + T ₃ ) ÷ 3600 + [(Va ÷ Vb) * (Wa ÷ [U ₁ + U ₂ ... U _x ) * 5] ÷ Ly) * Va] ÷ (T ₂ −T ₃ ) ÷ 3600

Va: Device rated voltage value (stored in ROM 42 in advance, for example, 100 V)
Vb: Heater rated voltage value (stored in ROM 42 in advance, eg 97 V)
Wa: Heater W (previously stored in ROM 42, eg, 800 W)
D _x : lighting duty log K _x : lighting duty log storage count Ds: lighting duty log transition D _x + D _x−1
U _x : lighting duty log after Ds ≦ 5.0% (5.0% is an example)
Ly: Number of times the lighting duty log is stored after Ds ≦ 5.0% T ₁ : Acquisition start time of lighting duty log T ₂ : Acquisition end time of lighting duty log T ₃ : lighting duty log when Ds ≦ 5.0% Storage time

  As shown in FIG. 4 described above, when the region (d) where the fluctuation of the power consumption value of the fixing unit 20 is gradual is determined based on the transition of the lighting duty log, the power consumption information and the heating time acquired at a measurement interval are used. Calculate the power consumption value. Then, the power consumption amount of the halogen heater 21 is calculated based on the calculated power consumption value. As a result, the software load and the amount of information retained in the ROM 42 can be reduced together with the effects described above.

FIG. 7 is a flowchart showing a third example of the processing content for calculating the power consumption amount from the power consumption value obtained by using the heater lighting ratio (lighting duty) with the elapse of the heating time and the heating time.
In the case of this example, the CPU 41 realizes the following functions by executing a required program stored in the storage unit.
(4) A function for determining whether or not fluctuations in the power consumption value are stable (this function is referred to as “second power consumption determination unit 41d”).
When the power consumption determining unit 41d determines that the fluctuation of the power consumption value is stable, the power consumption calculating unit 41b is configured to use the halogen heater based on the power consumption value calculated based on the preset power consumption information and the heating time. 21 power consumption is calculated.
Detailed processing contents are shown below.

Step 1 (abbreviated as “SB1” in FIG. 7, the same applies hereinafter): Acquisition of the lighting duty log is started.
Step 2: The acquisition start time (T ₁ ) of the lighting duty log is stored in the storage unit.
Step 3: Set the number of times to store the lighting duty log (K = 0).
Step 4: Store the lighting duty log (D _x ).
Step 5: Calculate the transition of the lighting duty log (Ds = D _x -D _x-1 ).
Step 6: It is determined whether or not Ds> 2.0%. If Ds> 2.0%, the process proceeds to Step 7; otherwise, the process proceeds to Step 7a.
Step 7: Count up the number of times the lighting duty log is stored (K _x = K + 1).
Step 8: It is determined whether or not the lighting duty log is end. When it is determined that the lighting duty log is end, the process returns to step 4;

Step 7a: Since Ds> 2.0% is not satisfied in Step 6, the lighting duty log (Da) of Ds ≦ 2.0% is stored.
Step 8a: The lighting duty log storage time of Ds ≦ 2.0% is stored (T3).
Step 9a: The lighting duty log is ended, and the process proceeds to step 10.

Step 10: Store the acquisition completion time of the lighting duty log, and proceed to Step 12.
Step 11: Calculate power consumption.
The power consumption in this example is calculated as follows.
[[Va ÷ Vb] ^1.54 * (Wa ÷ [D ₁ + D ₂ ... D _x ] ÷ K _x ) * Va] ÷ (T ₂ −T ₁ + T ₃ ) ÷ 3600 + [(Va ÷ Vb) ^1.54 * (Wa ÷ Da * Va) ÷ (T ₂ −T ₃ ) ÷ 3600

Va: Device rated voltage value (stored in ROM 42 in advance, for example, 100 V)
Vb: Heater rated voltage value (stored in ROM 42 in advance, eg 97 V)
Wa: Heater W (previously stored in ROM 42, eg, 800 W)
D _x : lighting duty log K _x : lighting duty log storage count Ds: lighting duty log transition D _x -D _x-1
Da: lighting duty log when Ds ≦ 2.0% (2.0% is an example)
T ₁ : Acquisition start time of lighting duty log T ₂ : Acquisition end time of lighting duty log T ₃ : Storage time of lighting duty log when Ds ≦ 2.0%

  As shown in FIG. 4, a stable region (e) in which the fluctuation of the power consumption value of the fixing unit 20 is stable is determined based on the transition of the lighting duty log. Then, the power consumption amount of the halogen heater 21 is calculated based on the power consumption value calculated by the average lighting duty predicted from the fluctuations so far. As a result, the software load and the amount of information retained in the ROM 42 can be reduced together with the effects described above.

  FIG. 8 is a flowchart showing a fourth example of the processing content for calculating the power consumption amount from the heating power value and the heating time obtained using the heater lighting ratio (lighting duty) with the elapse of the heating time.

Step (abbreviated as “SC1” in the figure. The same applies hereinafter) 1: The voltage value is detected.
Step 2: Store the detection result of the voltage value (Va).
Step 3: Start obtaining the lighting duty log.
Step 4: The acquisition start time (T ₁ ) of the lighting duty log is stored in the storage unit.
Step 5: Set the number of times to store the lighting duty log (K = 0).
Step 6: Store the lighting duty log (D _x ).
Step 7: Count up the number of times the lighting duty log is stored (K _x = K + 1).

Step 8: It is determined whether or not the lighting duty log is at the end. If it is determined that the lighting duty log is at the end, the process returns to step 6;
Step 9: The acquisition completion time (T ₂ ) of the lighting duty log is stored, and the process proceeds to Step 10.

Step 10: Calculate power consumption.
The power consumption in this example is calculated as follows.
[[Va ÷ Vb] ^1.54 * (Wa ÷ [D ₁ + D ₂ ... D _x ] ÷ Kx) * Va] ÷ (T ₂ −T ₁ ) ÷ 3600

Va: voltage detection result Vb: heater rated voltage value (stored in ROM 42 in advance, for example, 97 V)
Wa: Heater W (previously stored in ROM 42, eg, 800 W)
Dx: lighting duty log Kx: lighting duty log storage count T ₁ : lighting duty log acquisition start time T ₂ : lighting duty log acquisition end time

  According to this example, the detected voltage value by the voltage detection circuit 51, the power consumption value calculated by the power consumption information such as the heater lighting ratio (lighting duty), the temperature target, the power target, etc., and the heating time are used. Thus, the deviation from the actual power consumption can be further reduced.

FIG. 9 is a flowchart showing a fifth example of the processing content for calculating the power consumption amount from the power consumption value obtained by using the heater lighting ratio (lighting duty) with the elapse of the heating time and the heating time.
Step (abbreviated as “SD1” in the figure. The same applies hereinafter) 1: Acquisition of the lighting duty log is started.
Step 2: The acquisition start time (T ₁ ) of the lighting duty log is stored in the storage unit.
Step 3: Set the number of times to store the lighting duty log (K = 0).
Step 4: Store the lighting duty log (D _x ).
Step 5: Count up the number of times the lighting duty log is stored (Ks = K + 1).

Step 6: It is determined whether or not the number of times Ks of storing the lighting duty log is 30 or more. If it is determined that the number of stored times Ks is 30 or more, the process proceeds to Step 7. Otherwise, the process proceeds to Step 7a.
Step 7: It is determined whether or not the lighting duty log is end. When it is determined that the lighting duty log is end, the process proceeds to step 12; otherwise, the process returns to step 4.

Step 7a: Since the stored number of times of lighting duty Ks> 30 in step 6, the lighting duty log storage time (T ₃ ) of Ks ≦ 30 is stored in the storage unit.
Step 8a: The lighting duty log (U _x ) is stored in the storage unit.
Step 9a: Count up the number of times the lighting duty log is stored (Ly = L + 1).

Step 10a: It is determined whether or not the lighting duty log is end. When it is determined that the lighting duty log is end, the process proceeds to step 12; otherwise, the process proceeds to step 11a.
Step 11a: It is determined whether or not the lighting duty log storage count Ly is a multiple of “5”, and if it is a multiple of “5”, return to Step 8a, otherwise return to Step 9a to continue the processing.

Step 12: The acquisition completion time (T ₂ ) of the lighting duty log is stored, and the process proceeds to Step 13.
Step 13: Calculate power consumption.
The power consumption in this example is calculated as follows.
[[Va ÷ Vb] ^1.54 * (Wa ÷ [D ₁ + D ₂ ... D _x ] ÷ Kx) * Va] ÷ (T ₂ −T ₁ + T ₃ ) ÷ 3600 + [(Va ÷ Vb) * (Wa ÷ [U ₁ + U ₂ ... U _x ) * 5] ÷ Ly) * Va] ÷ (T ₂ −T ₃ ) ÷ 3600

Va: Device rated voltage value (stored in ROM 42 in advance, for example, 100 V)
Vb: Heater rated voltage value (previously stored in ROM 42, eg 97 V)
Wa: Heater W (previously stored in ROM 42, eg, 800 W)
D _x : lighting duty log K _x : number of times the lighting duty log is stored Ds: transition of lighting duty log D _x -D _x-1
Lighting duty log after U _x : K _x > 30 (30 is an example)
Ly: Number of times of storage of lighting duty log after K _x > 30 T ₁ : Acquisition start time of lighting duty log T ₂ : Acquisition end time of lighting duty log T ₃ : Storage time of lighting duty log when Kx> 30

  According to this example, an area where the fluctuation of the power value is gentle is determined based on the elapsed time from the start of printing, and the power consumption amount is determined based on the power consumption value and the heating time based on the lighting duty log acquired at predetermined time intervals. Calculated. As a result, the software load and the amount of information retained in the ROM 42 can be reduced.

  In the above-described embodiment, the flowcharts showing the first to fifth examples of the processing content for calculating the power consumption amount are individually shown, but it is needless to say that the processing content may be a combination of these. .

DESCRIPTION OF SYMBOLS 10 Operation part 11 Automatic document feeder 12 Image reading device 13 Writing unit 14 Printer unit 15 Developing device 16 Photosensitive drum 17 Conveying belt 20 Fixing part 21 Halogen heater (heating means)
30 Display Unit 40 Control Board 41 CPU
41a Power consumption value calculating means 41b Power consumption calculating means 41c Power consumption determining means 41d Power consumption determining means 42 ROM
44 Timer (heating time measuring part)
50 PSU
51 Voltage Detection Circuit 52 Fixing Control Circuit 53 DC Converter A Digital Multifunction Machine (Image Forming Apparatus)

JP 2011-085796 A JP 2013-083732 A

Claims (6)

In an image forming apparatus having a fixing unit having a heating unit for heating and fixing an image formed on a medium, and a heating time measuring unit for measuring a heating time by the heating unit at a predetermined interval.
Based on power consumption information of the heating means that is sequentially updated as the heating time elapses, a power consumption value calculating means that calculates a power consumption value of the heating means,
An image forming apparatus comprising: a power consumption amount calculating unit that calculates a power consumption amount of the heating unit based on the power consumption value calculated by the power consumption value calculating unit and the heating time. Comprising first power consumption determining means for determining whether or not fluctuations in the power consumption value are stable;
When it is determined by the first power consumption determination means that the fluctuation of the power consumption is stable, the power consumption amount output means acquires the power consumption information and the heating time acquired at intervals of the heating time measured by the heating means. The image forming apparatus according to claim 1, wherein the power consumption amount of the heating unit is calculated based on the power consumption value calculated by the step. A second power consumption determining means for determining whether or not the fluctuation of the power consumption is stable;
When it is determined by the second power consumption determining means that fluctuations in power consumption are stable, the power consumption calculating means is configured to use the heating means based on the power consumption value and the heating time calculated based on power consumption information set in advance. The image forming apparatus according to claim 1, wherein the power consumption amount is calculated. Having a voltage detection circuit,
The power consumption calculating means calculates the power consumption of the heating means based on a detected voltage value detected by the voltage detection circuit, a power consumption value calculated by power consumption information, and a heating time. Item 4. The image forming apparatus according to Item 1, 2 or 3. It has a third power consumption determination means for determining whether or not the fluctuation of the power consumption is stable, and when it is determined by the third power consumption determination means that the fluctuation of the power consumption value is stable,
The power consumption amount calculating means calculates the power consumption amount of the heating means based on the power consumption value calculated from the elapsed time from the start of printing and the power consumption information acquired at an acquisition time interval. Item 2. The image forming apparatus according to Item 1. Calculation of power consumption used in an image forming apparatus having a fixing unit having a heating unit for heating and fixing an image formed on a medium and a heating time measuring unit for measuring a heating time by the heating unit at a predetermined interval. In the method
Based on the power consumption information of the heating means that is sequentially updated as the heating time elapses, the power consumption value of the heating means is calculated,
A power consumption calculation method, wherein the power consumption of the heating means is calculated based on the calculated power consumption value and heating time.