JPH06164798A - Image forming device - Google Patents

Abstract

PURPOSE:To effectively reduce production of noise by comparing environmental noise measured at plural prescribed locations and reducing either of the noises when the result of comparison indicates a specified or large level. CONSTITUTION:Only the noise generated by a cooling fan 35 is a noise source in the standby state and a microphone 2 is placed on a position P where office workers are usually resident. In this case, a CPU 36 stops the fan 35 once and allows the microphone 2 to measure the environmental noise in a state that no noise is generated from a main body 1. The output signal of the microphone is fetched and stored in a memory 38. Then the CPU 36 rotates the fan 35 to allow the microphone 2 to measure the environmental noise L1 at the location in the standby state and fetches the output signal and stores it in the memory 38. Then the CPU 36 compares the noise levels between L0, L1 stored in the memory 38 and calculates the difference to compare the calculated value with the standard noise DELTAL0 in a memory 37. When the calculated value is larger, the fan 35 is stopped to reduce the noise generated in the main body to reduce the environmental noise.

Description

Detailed Description of the Invention

[0001]

The present invention relates to a copying machine, a facsimile,
The present invention relates to an image forming apparatus such as a printer.

[0002]

2. Description of the Related Art In recent years, there has been an increasing movement to improve the office environment. The equipment used in the office is required to be quiet in order to improve the living environment of the office. Image forming apparatuses such as copiers, facsimiles, printers, etc. are called office automation equipments, and are often used in offices, and noises often cause problems.

By the way, the noise generated by the image forming apparatus may or may not be a problem depending on the environmental noise of the office and the place where the office worker normally operates. As an example of environmental noise in an office, in an office along a road with heavy traffic, the noise of the image forming device does not pose a problem due to heavy traffic noise during the day, but the amount of traffic decreases in the morning and evening and image formation is performed. Device noise becomes a problem.

Further, in a place where an office worker is present, the noise intensity (sound pressure) is inversely proportional to the distance from the noise source. Therefore, a person who is in the immediate vicinity of the image forming apparatus is concerned about the noise, but a person who is far from the image forming apparatus does not notice the noise so much. Sound has directivity. If the noise source is attached to the back of the image forming apparatus, a person at the back of the image forming apparatus feels noisy due to the noise generated by the image forming apparatus, but a person at the front of the image forming apparatus feels noisy. I don't feel too noisy about the generated noise.

In an image forming apparatus such as a copying machine,
Noise is generated during standby when the power is on and copying is not performed, and during image formation during copying. A cooling fan for cooling the fixing device and the electric system generates noise during standby, and noise due to driving of an image forming device (developing device, optical system, etc.) and a paper feeding device occurs during image formation. In addition, the cooling fan is often attached to the paper discharge side of the copying machine, and the noise generated by the cooling fan is often heard by a person on the paper discharging side of the copying machine.

As a means for reducing the noise during standby of the image forming apparatus, there is a means of reducing noise by stopping the cooling fan during standby in the copying machine.
No. 6 publication. Further, in a copying machine, environmental noise is measured, and the measured value is compared with a preset value. When the measured value is larger than the preset value, the cooling fan is stopped to reduce the noise generated by the copying machine. Something like that is proposed. Further, a copying machine using an active control (measuring noise at a certain place and outputting a sound wave having a wavelength opposite to that of the noise to cancel the noise) has been proposed.

[0007]

In the above copying machine, since the noise is reduced by stopping the cooling fan during standby, it is necessary to stop the heating of the fixing device when the cooling fan is stopped. Even if the temperature drops when the cooling fan is stopped during standby and it is desired to make a copy immediately, it is inconvenient because a copy cannot be made until the fixing device reaches a certain temperature and copying is possible. Further, where the environmental noise is so great that the noise of the cooling fan is not noticeable, it is not necessary to stop the cooling fan during standby to reduce the noise.

Further, in the above copying machine, the environmental noise is measured, and when the measured value is larger than a preset value, the cooling fan is stopped to reduce the noise generated by the copying machine. When environmental noise is too loud to be noticeable, it is now possible to make a copy. However, the influence of the noise generated by the copying machine on the environmental noise of the place where the noise is measured is ignored. Although the environmental noise at a distance from the copying machine is measured and the noise generated by the copying machine has almost no influence on the environmental noise, the cooling fan may be stopped when the environmental noise is large.

For example, it is assumed that the cooling fan is stopped when the measured noise is 47 dB or less. When the noise generated by the cooling fan has a very small effect on the environmental noise of the place by measuring the noise at a place away from the copying machine (for example, the environmental noise when there is no cooling fan is about 46.8 dB). Also, the measured noise is 47d
If it is B, the cooling fan is stopped. In this case, since it is not necessary to stop the cooling fan, the cooling fan is stopped. Therefore, even if a user wants to make a copy immediately, there is a problem that a copy cannot be taken until the fixing device reaches a constant temperature.

Further, although the above-mentioned copying machine uses the active control means, the active control means requires complicated signal processing means, a speaker, etc., which complicates the apparatus and raises the cost. In addition, the area where noise can be canceled is quite narrow, and there is a high possibility that the area outside the area may become noisy due to the use of the active control means.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an image forming apparatus capable of improving the above-mentioned drawbacks, suppressing complication and cost increase of the apparatus and effectively reducing generated noise.

[0012]

In order to achieve the above object, the invention according to claim 1 is an image forming apparatus having a main body for generating an image by generating noise, which is a predetermined place apart from the main body. And a first environmental noise measured at the predetermined location by the noise measuring means when the main body is not generating noise, and when the main body is generating noise And a noise reducing unit for comparing the second environmental noise measured at the predetermined place by the noise measuring unit and reducing the second environmental noise when the comparison result is equal to or more than a specified value. Is.

According to a second aspect of the present invention, there is provided an image forming apparatus having a main body which forms an image and generates different noises during standby and during image formation, and measures the noise at a predetermined location away from the main body. A noise measuring unit, a first environmental noise measured at the predetermined place by the noise measuring unit when the main body does not generate noise, and a first environmental noise measured at the predetermined place by the noise measuring unit during standby. When the comparison result is compared with the second environmental noise and the comparison result is equal to or more than a predetermined value, the second environmental noise is reduced during standby and the second reduced noise during standby during image formation. When the environmental noise is compared with the third environmental noise measured at the predetermined location by the noise measuring means when the image of the main body is formed, the comparison result is equal to or more than a predetermined value, the above-mentioned Third If the result of comparison between the first environmental noise and the second environmental noise is less than or equal to a prescribed value that has been prescribed in advance, the environmental noise is reduced. Noise that compares the noise with the third environmental noise measured at the predetermined location by the noise measuring means, and reduces the third environmental noise when the comparison result is equal to or more than a predetermined prescribed value. And reduction means.

According to a third aspect of the present invention, there is provided an image forming apparatus having a main body that forms an image and generates different noises during standby and during image formation, and environmental noise is generated at a plurality of locations apart from the main body. A plurality of noise measuring means for measuring, an average value of the first environmental noises respectively measured at the plurality of places by the plurality of noise measuring means when the main body does not generate noise, and the main body is noisy. Is generated, the average values of the second environmental noises respectively measured at the plurality of places by the plurality of noise measuring means are obtained, and these average values are compared, and the comparison result is equal to or more than a specified value. In this case, noise reducing means for reducing the noise generated by the main body is provided.

[0015]

According to the first aspect of the present invention, the noise at a predetermined place apart from the main body is measured by the noise measuring means. Then, the noise reduction means includes the first environmental noise measured at the predetermined location by the noise measuring means when the main body does not generate noise, and the predetermined environmental noise measured by the noise measuring means when the main body generates noise. The second environmental noise measured at the place is compared, and the second environmental noise is reduced when the comparison result is equal to or more than a specified value. Therefore, the noise reduction unit can surely judge how much the noise generated by the image forming apparatus affects the predetermined place, and can reduce the noise generated by the image forming apparatus only when the influence is large. Moreover, the region where the noise is desired to be reduced by the output of the sound wave does not become loud on the contrary. Therefore, the generated noise can be effectively reduced, and the complexity and cost of the device can be suppressed.

According to the second aspect of the present invention, the noise at a predetermined place apart from the main body is measured by the noise measuring means. The noise reduction means includes a first environmental noise measured at the predetermined location by the noise measurement means when the main body does not generate noise, and a second environmental noise measured at the predetermined location by the noise measurement means during standby. When the comparison result is equal to or more than a predetermined value, the second environmental noise is reduced during standby and the second environmental noise reduced during standby during image formation. , The third environmental noise measured by the noise measuring means at the predetermined place during image formation of the main body is compared, and when the comparison result is equal to or more than a predetermined prescribed value, the third environmental noise is detected. Reduced, first
When the comparison result of the environmental noise of No. 2 and the second environmental noise is less than a specified value which is specified in advance, the second environmental noise at the time of standby when the image is formed on the main body and the noise measuring unit measures at the predetermined place. The third environmental noise is reduced when the comparison result is equal to or more than a predetermined value that is specified in advance.

Therefore, the noise reduction means surely determines how much the noise generated during the standby time of the image forming apparatus and the noise generated during the image formation affect the predetermined place, and only when the influence is large, the image is reduced. It is possible to reduce the noise generated by the forming device during standby and during image formation. Moreover, the region where the noise is desired to be reduced by the output of the sound wave does not become loud on the contrary. Therefore, the generated noise can be effectively reduced, and the complexity and cost of the device can be suppressed.

According to the third aspect of the present invention, the environmental noise is measured by a plurality of noise measuring means at a plurality of places apart from the main body. Then, the noise reduction means is an average value of the first environmental noises measured at the plurality of locations by the plurality of noise measuring means when the main body is not producing noise, and when the main body is producing noise. The average value of the second environmental noise measured at each of the plurality of locations by the plurality of noise measuring means is calculated, and these average values are compared.
When the comparison result is equal to or more than the specified value, the noise generated by the main body is reduced.

Therefore, the noise reducing means can surely judge how much the noise generated by the image forming apparatus has an influence, and can reduce the noise generated by the image forming apparatus only when the influence is great. Moreover, the region where the noise is desired to be reduced by the output of the sound wave does not become loud on the contrary. Therefore, the generated noise can be effectively reduced, and the complexity and cost of the device can be suppressed.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIGS. 3 and 4 show a first embodiment of the present invention. The first embodiment is an embodiment of the invention described in claim 1 and is an example of a digital copying machine. This copying machine comprises a main body 1 installed at a predetermined place in an office and a microphone 2 arranged at a predetermined place apart from the main body 1 in the same office. The main body 1 is provided with a document placing table 3 and a pressure plate 4 made of contact glass on the upper part, and an operation panel 5 on the front side. Also, the main body 1 is
An air outlet 6 and a paper discharge tray 7 are provided on the left side, and paper feed cassettes 8 and 9 are provided on the right side.

A copy start key 10 is provided on the operation panel 5.
Also, various operation keys 11 for setting the number of copies, setting of reduction / enlargement ratio, etc. are provided, and the number of copies, setting of reduction / enlargement ratio, etc. are performed by operating the operation key 11, and the copy start key 10 is operated. By the operation, the main body 1 starts the copying operation. The microphone 2 constitutes noise measuring means for measuring environmental noise.

FIG. 2 shows the internal structure of the main body 1. The main body 1 has an image reading unit 12 and a printer unit 13. In the image reading unit 12, the original placed on the contact glass 3 is illuminated by the light source 14, and the reflected light is imaged on the CCD on the image reading plate 19 by the lens 18 via the mirrors 15 to 17. While being photoelectrically converted, the original is scanned by the movement of the light source 14 and the mirrors 15 to 17 to read an image. Image reading board 1
Reference numeral 9 A / D converts the output image signal of the CCD and outputs it to an image processing unit (not shown). This image processing unit performs predetermined processing on the image signal from the image reading plate 19 and outputs it to the printer unit 13. To do.

In the printer unit 13, the image carrier 20 formed of an organic photoconductor drum is rotationally driven in the direction of the arrow by the motor during the copying operation, and is uniformly charged by the charging charger 21 and then exposed by the writing device 22 to form an image. Written to form an electrostatic latent image. In the writing device 22, the semiconductor laser is driven by the modulation drive circuit by the image signal from the image processing section, and outputs a laser beam whose intensity changes according to the image signal. This laser light is deflected by the polygon mirror 23 and is applied to the photoconductor drum 20 through the optical system, and the photoconductor drum 20 is exposed with the laser light 24 to form an image and an electrostatic latent image is formed. The polygon mirror 23 is rotationally driven by a polygon motor 25.

The electrostatic latent image on the photosensitive drum 20 is developed into a visible image by the developing device 26, and the transfer paper in the paper feed cassettes 8 and 9 is selectively fed by the paper feed rollers 27 and 28. The paper is sent and sent to the registration roller 29. This transfer paper is sent out with its front end aligned with the visible image on the photosensitive drum 20, the transfer charger 30 transfers the visible image on the photosensitive drum 20, and the separating charger 31 separates it from the photosensitive drum 20. It is conveyed by the conveyor belt 32.

Further, a visible image is fixed on the transfer paper by the fixing device 33, and the transfer paper is discharged to the paper discharge tray 7. Also,
The photoconductor drum 20 has a cleaning device 3 after the transfer paper is separated.
The residual toner is removed by 4 and the residual charge is removed by the quenching lamp. The cooling fan 35 is installed near the fixing device 33, and discharges the air in the printer unit 13 from the exhaust port 6 during rotation to cool the fixing device 33 and the electrical system. The above-described copying operation is started by turning on the copy start key 10 and is repeated continuously by the number of copies set by the operation key 11.

FIG. 1 shows the circuit configuration of the first embodiment. The microcomputer (CPU) 36 takes in the output signal of the microphone 2 and the standard value in the memory 37 and reads / writes necessary data from / into the memory 38 while charging the charger 21, the writing device 22, the developing device 26, the transfer charger 30, and the separation. Charger 32, cleaning device 3
Image forming system 39 including 4 and fixing system 40 including fixing device 33
A paper feed system 39 including the paper feed cassettes 8 and 9, paper feed rollers 27 and 28, and registration rollers 29, and a cooling fan 35.
And controls the optical system 40 including the light source 14 and the mirrors 15 to 17.

The CPU 36 normally drives the cooling fan 35 during standby of the main body 1 and during copying, and the noise generated by the main body 1 includes the noise generated by the cooling fan 35 during standby. The first embodiment is an example of reducing the noise caused by the cooling fan 35 at a predetermined place in the office.

FIG. 5 shows a part of the processing flow of the CPU 36.

It is assumed that only the noise generated by the cooling fan 35 is a noise source during standby. The microphone 2 is placed in a place P where an office worker normally exists (for example, on a desk) P. C
The PU 36 first stops the cooling fan 35 during standby so that the main body 1 does not generate noise, and the environmental noise L0
Is measured by the microphone 2 and the output signal of the microphone 2 is captured and stored in the memory 38. Environmental noise L
0 is the environmental noise at the location P when there is no first embodiment (when the copying machine of the first embodiment does not generate noise).

Next, the CPU 36 rotates the cooling fan 35 to cause the microphone 2 to measure the environmental noise L1 at the place P at the time of standby (when the main body 1 is making noise), and the microphone 2 is measured. Of the output signal of the above and is stored in the memory 38. Next, the CPU 36 causes the memory 3
The environmental noises L0 and L1 stored in 8 are compared and the difference (L
1-L0) is calculated, and the difference (L1-L0) and the memory 3
It is determined whether (L1-L0) is smaller than the standard value ΔL0 by comparing with a standard value ΔL0 defined in advance in 7.

In the CPU 36, (L1-L0) is the standard value Δ
If it is smaller than L0, the noise generated by the main body 1 is at the above-mentioned location P.
The cooling fan 35 is rotated as it is because it is determined that the environmental noise in the above is not so affected. Also, C
When (L1-L0) is not smaller than the standard value ΔL0, the PU 36 determines that the generated noise of the main body 1 makes the environmental noise at the place P large (the place P is noisy), In order to reduce the noise generated by the main body 1 and reduce the environmental noise at the place P, the cooling fan 35 is stopped to stop the heating of the fixing device 33.

The noises L0 and L1 are preferably equivalent noise levels per certain time (for example, several seconds) so as not to be affected by the impact noise. As a specific example, assuming that ΔL0 = 2 dB and L0 = 42 dB, if L1 = 43 dB, then (L1−L0) <ΔL0, and the noise generated by the main body 1 is cooled at place P so that it is not so noisy. The fan 35 will be rotated as it is.

If L1 = 46 dB, (L1−L0)> ΔL0, and the cooling fan 35 is stopped because the noise generated by the main body 1 makes the place P noisy.

By doing so, it is surely judged whether or not the influence of the noise generated in the first embodiment on the environmental noise at the place P is large, and the first noise is judged from the environmental noise at the place P. When the influence of noise generated in the above embodiment is large, this can be reduced. Therefore, as compared with the case where the cooling fan 35 is always stopped, when the influence of the noise generated in the first embodiment on the environmental noise at the place P is small, the fixing device 33 is used when a copy is desired.
There is no need to wait until the temperature reaches the fixing temperature.

In the second embodiment of the present invention, a timer 43 is provided as shown in FIG. 6 in the first embodiment, and a CPU 43 is provided every time the timer 43 measures a fixed time.
36 executes the processing shown in FIG. For example, ΔL0 = 2
dB at some hour during the day, L0 = 52.0d
If B and L1 = 52.8 dB, then (L1−L0) <ΔL0, and it is assumed that the noise generated in the first embodiment is not so noisy at the place P, and the cooling fan 35 is rotated as it is. Such an operation is performed for a certain time (for example, 3
It is performed every 0 minutes.

At night, L0 = 45 dB, L1 = 48 d
When it becomes B, (L1−L0)> ΔL0, and it is judged that the noise generated in the first embodiment makes the place P noisy, and the cooling fan 35 is stopped.

By having the timer 43 in this way, even if the environmental noise changes with time, it is surely judged whether or not the influence of the noise generated by the copying machine on the environmental noise at that location is great at that time. This can be reduced when the influence of the noise generated by the copying machine on the environmental noise in the place is large.

Further, in the third embodiment of the present invention, the CPU 36 performs the processing shown in FIG. 7 in place of the processing shown in FIG. 5 in the second embodiment. The cooling fan 35 can be controlled in two stages. When the cooling fan 35 is rotating at a high speed (in a normal state), the fixing roller of the fixing device 33 is at a high temperature (for example, about 180 ° C.), and copying is possible without waiting time. When the cooling fan 35 is rotating at a low speed, the fixing device 33
The fixing roller of No. 1 is not hot enough to make a copy immediately, but it can make a copy in a shorter waiting time than when the cooling fan 35 is stopped.

As shown in FIG. 7, the CPU 36 temporarily stops the cooling fan 35 during standby to cause the microphone 2 to measure the environmental noise L0 in a state where the main body 1 does not generate noise, and fetches the output signal of the microphone 2. To be stored in the memory 38. Next, the CPU 36 causes the cooling fan 3
By rotating 5 at a high speed, the microphone 2 is caused to measure the environmental noise L1 at the place P in the standby state (in the normal state), and the output signal of the microphone 2 is captured and stored in the memory 38. Next, the CPU 36 compares the environmental noises L0 and L1 stored in the memory 38 and compares the difference (L1-L).
0) is calculated, and the difference (L1−L0) is compared with a standard value ΔL0 defined in advance in the memory 37 (L1−L0).
L0) is smaller than the standard value ΔL0.

In the CPU 36, (L1-L0) is the standard value Δ
When it is smaller than L0, it is determined that the noise generated in the third embodiment does not significantly affect the environmental noise at the location P, and the cooling fan 35 is rotated at high speed as it is. Further, in the CPU 36, (L1-L0) is the standard value ΔL.
If it is not less than 0, the cooling fan 35 is rotated at a low speed to control the temperature of the fixing device 33 to a low temperature, and the microphone 2 is caused to measure the environmental noise L1 ′ at the place P,
The output signal of the microphone 2 is captured and stored in the memory 38.
Remember.

Next, the CPU 36 compares the environmental noises L0 and L1 'stored in the memory 38 and compares them (L1'-L).
0) is calculated, and the difference (L1′−L0) is compared with a standard value ΔL0 defined in advance in the memory 37 (L0).
1'-L0) is smaller than the standard value ΔL0. When (L1'-L0) is smaller than the standard value ΔL0, the CPU 36 determines that the noise generated in the third embodiment is the above-mentioned location P.
Therefore, the cooling fan 35 is rotated at a low speed as it is. Also, C
When (L1′−L0) is not smaller than the standard value ΔL0, the PU 36 determines that the noise generated in the third embodiment makes the place P noisy and stops the cooling fan 35 to fix the fixing device. Stop heating of 33.

By doing so, it is surely judged whether or not the influence of the noise generated in the third embodiment on the environmental noise at the place P where the microphone 2 is present is large, and the environmental noise at the place P is judged. On the other hand, when the influence of the noise generated in the third embodiment is large, it is possible to judge how much the influence is, and to reduce the generated noise of the third embodiment stepwise according to the degree of the influence. it can. Therefore,
When it is desired to make a copy, it is possible to minimize the waiting time until the temperature of the fixing device rises to the copy enable temperature.

The fourth embodiment of the present invention is an example in which the generated noise is different during standby and during image formation (during copying). The fourth embodiment is an embodiment of the invention described in claim 2, and in the first embodiment, the CPU 36 performs the processing shown in FIG. 8 instead of the processing shown in FIG. CPU 36
As shown in FIG. 8, the cooling fan 35 is temporarily stopped during standby to cause the microphone 2 to measure the environmental noise L0 while the main body 1 does not generate noise, and the output signal of the microphone 2 is captured and stored in the memory 38. .

Next, the CPU 36 rotates the cooling fan 35 to wait for the environmental noise L1 at the place P during standby.
Is measured by the microphone 2 and the output signal of the microphone 2 is captured and stored in the memory 38. Next, CP
U36 compares the environmental noises L0 and L1 stored in the memory 38, calculates the difference (L1−L0), and calculates the difference (L1
-L0) and a standard value Δ defined in advance in the memory 37
By comparing L0 with (L1−L0) and determining whether or not (L1−L0) is smaller than the standard value ΔL0, it is determined whether or not the noise generated by the main body 1 is acceptable at the location P.

In the CPU 36, (L1-L0) is the standard value Δ
If it is smaller than L0, it is determined that the noise generated in the fourth embodiment does not significantly affect the environmental noise at the location P, and the cooling fan 35 is rotated as it is. CP
When the copy start key 10 is pressed in this state, the U 36 ends the copying operation by the image forming system 39 or the like if the number of copies set by the operation key 11 is one. Further, when the number of copies set by the operation key 11 is plural, the CPU 36 sets 1 by the image forming system 39 or the like.
The copying operation of the first sheet is performed, and the environmental noise L2 at the place P is measured by the microphone 2 during that time, and the output signal of the microphone 2 is captured and stored in the memory 38.

Next, the CPU 36 compares the environmental noises L1 and L2 stored in the memory 38 and compares them (L2-L1).
Is calculated, and this difference (L2-L1) is compared with a standard value ΔL0 'defined in advance in the memory 37 (L2-L1).
It is determined whether 1) is smaller than the standard value ΔL0 ′. C
When (L2-L1) is smaller than the standard value ΔL0 ′, the PU 36 determines that the noise generated in the fourth embodiment does not significantly affect the environmental noise at the place P, and the second and subsequent sheets are determined. Image forming operation (copying operation).

When (L2-L1) is not smaller than the standard value .DELTA.L0 ', the CPU 36 increases the environmental noise at the location P (the location P is noisy). Noise is generated by the main body 1 by controlling each unit of the printer unit 13 to switch the image forming speed (copying speed) to a speed lower than the normal speed after the completion of the copying operation for the first sheet. And the copying operation for the second and subsequent sheets is performed.

When (L1-L0) is not smaller than the standard value ΔL0, the CPU 36 increases the environmental noise at the place P (the place P is noisy). Cooling fan 3
5 and the fixing roller heating of the fixing device 33 are stopped to reduce the noise of the main body 1. When the copy start key 10 is pressed in this state, the CPU 36 starts heating the fixing roller of the fixing device 33. When the temperature of the fixing roller of the fixing device 33 reaches the temperature at which copying can be performed, the CPU 36 ends the copying operation by the image forming system 39 or the like if the number of copies set by the operation key 11 is one.

When the number of copies set by the operation key 11 is plural, the CPU 36 causes the image forming system 39 or the like to perform the copying operation of the first sheet, and the environmental noise L2 at the place P is generated during the copying operation. The microphone 2 is caused to measure the output signal of the microphone 2 and stored in the memory 38.

Next, the CPU 36 compares the environmental noises L2 and L0 stored in the memory 38 and compares them (L2-L0).
Is calculated, and the difference (L2-L0) is compared with a standard value ΔL0 'defined in advance in the memory 37 (L2-L0).
0) is smaller than the standard value ΔL0 ′. C
When (L2-L0) is smaller than the standard value ΔL0 ', the PU 36 determines that the noise generated in the fourth embodiment does not significantly affect the environmental noise at the place P, and the second and subsequent sheets. Image forming operation (copying operation).

When (L2-L0) is not smaller than the standard value .DELTA.L0 ', the CPU 36 increases the environmental noise at the location P (the location P is noisy when the noise generated in the fourth embodiment is large). Noise is generated by the main body 1 by controlling each unit of the printer unit 13 to switch the image forming speed (copying speed) to a speed lower than the normal speed after the completion of the copying operation for the first sheet. And the image forming operation (copying operation) for the second and subsequent sheets is performed.

As described above, in the fourth embodiment, the environmental noise L2 at the time of copying is compared with the environmental noise (L0 or L1) before performing the copying, and when this is large, the noise generated by the main body 1 at the time of copying. To reduce. It should be noted that the environmental noise L2 at the time of copying should be measured during the copying of the first sheet and set to the equivalent noise level. The reason is that the noise during copying is often impact noise, and the noise during copying cannot be evaluated simply by measuring a momentary noise.

The fourth embodiment can only reduce the noise generated by the main body 1 during the second and subsequent copies when a plurality of copies are continuously made. However, in the fourth embodiment, it is possible to reduce the noise generated by the main body 1 even when a timer is provided and copying is performed one by one. In this case, the CPU 36 first causes the microphone 2 to measure the environmental noise L2 when the first copy is made, and stores it in the memory memory 38. From this time, it is assumed that the environmental noise at the place P at the time of copying the main body 1 is L2 for a predetermined time (for example, 30 minutes) measured by the timer. The CPU 36 stores L2 and L stored in the memory 38.
1 or the difference between L2 and L0 (depending on the size relationship between L1 and L0) is calculated, and the difference is defined value Δ
It is determined whether it is smaller than L0 and stored in the memory 38. After copying the first sheet, place P at the time of copying another sheet within the above predetermined time (30 minutes).
The CPU 36 considers that the environmental noise of the
The difference between 2 and L1 or the difference between L2 and L0 is the specified value ΔL
If it is not smaller than 0, each unit is controlled to switch the image forming speed (copying speed) to a slow speed.

In many cases, there are a plurality of office workers in the office. People near the copier and people far from the copier feel differently about the noise generated by the copier. The copying machine may not be so noisy in a normal copying mode, but may be noisy in a special mode such as the double-sided copying mode because the generated noise has directivity. Therefore, in the fifth embodiment of the present invention,
In the first embodiment, the microphone 2 shown in FIG.
Multiple microphones 51, 52, 53.
.. is provided, and noises at a plurality of places in the office are measured by the microphones 51, 52, 53, respectively, and there is a place where the noise generated by the main body 1 has a strong influence on the environmental noise in the office. For example, the noise generated by the main body 1 is reduced. The number of microphones 51, 52, ... May be three, for example. The fifth embodiment is the embodiment of claim 1.

In the fifth embodiment, the CPU 36 performs the processing shown in FIG. 10 instead of the processing shown in FIG. 5 in the first embodiment. Here, the microphones are n microphones 51, 52, ... Installed at n locations P1 to Pn, respectively, where n office workers are usually located.
The noise reduction of the main body 1 is based on the stop of the cooling fan 35 during standby.

First, the CPU 36 temporarily stops the cooling fan 35 during standby so that the main body 1 does not generate noise, and the environmental noises L0p1, L0p2 ...
-L0pn is measured by the microphones 51 to 5n, and the output signals of the microphones 51 to 5n are captured and stored in the memory 38. Environmental noise L0p1, L0p2 ... L
0pn is the environmental noise at the locations P1 to Pn when the main body 1 is not present (when the main body 1 does not generate noise).

Next, the CPU 36 rotates the cooling fan 35 and stands by (when the main body 1 is making noise), and the environmental noises L1p1 and L1 at the above-mentioned places P1 to Pn.
The microphones 51 to 5n are caused to measure p2 ... L1pn, and the output signals of the microphones 51 to 5n are captured and stored in the memory 38. Next, the CPU 36 causes the environmental noises L0p1, L0p2, ... L0 stored in the memory 38.
pn, L1p1, L1p2 ... L1pn are compared, and the difference (L1p1-L0p1) for each of the locations P1 to Pn,
(L1p2-L0p2) ... (L1pn-L0pn)
And the difference (L1p1-L0p1), (L1p2
-L0p2) ... (L1pn-L0pn) and memory 3
(L1p1−L0p1), (L1p2−L0p)
2) ... Of (L1pn-L0pn), the standard value ΔL
It is determined whether or not there is even one that is not less than 0.

The CPU 36 uses (L1p1-L0p1),
(L1p2-L0p2) ... (L1pn-L0pn)
If none of them is less than the standard value ΔL0, it is determined that the noise generated by the main body 1 does not significantly affect the environmental noise in the office, and the cooling fan 3 is used.
Rotate 5 as it is. Further, the CPU 36 uses (L1
(p1-L0p1), (L1p2-L0p2) ... (L
1 pn-L0pn), if there is at least one that is not less than the standard value ΔL0, it is judged that the noise generated by the main body 1 increases the environmental noise in the office, and the noise generated by the main body 1 is reduced. In order to reduce the environmental noise in the office, the cooling fan 35 is stopped to fix the fixing device 33.
Stop heating.

By doing so, if the noise generated by the main body 1 affects the environmental noise even at any one of the plurality of places P1 to Pn, the copying machine of the fifth embodiment will be described. It is possible to reduce the generated noise and reduce the environmental noise in the office.

In the fifth embodiment, the standard value ΔL0 is the same for all the locations P1 to Pn. However, different people have different feelings of annoyance with the same noise. Therefore, the standard value ΔL0 is set to a value ΔL which is different for each of the locations P1 to Pn.
01, ΔL02, ΔL03 ... Set to ΔL0n (L1p1-L0p1), (L1p2-L0p2) ...
-(L1pn-L0pn) may be compared. For example, the microphones 51, 52, 53 ...
In the case of a book, the standard value ΔL0 is different for each of the locations P1 to P ΔL01 = 3 dB, ΔL02 = 3 dB, ΔL03 =
It may be 2 dB. By doing so, if a person who is extremely annoyed by noise is at a place where the microphone is located, even if the noise from the body 1 is smaller than that at the location where other microphones are located, the noise from the body 1 is reduced. Can be reduced to reduce environmental noise.

The noise generated by the image forming apparatus such as a copying machine may make the entire office loud. The sixth embodiment of the present invention is an example capable of preventing it.
It is an example of the described invention. In the sixth embodiment, the CPU 36 performs the processing shown in FIG. 11 instead of the processing shown in FIG. 10 in the fifth embodiment.

First, the CPU 36 temporarily stops the cooling fan 35 during standby so that the main body 1 does not generate noise, and the environmental noises L0p1, L0p2 ...
-L0pn is measured by the microphones 51 to 5n, and the output signals of the microphones 51 to 5n are captured and stored in the memory 38. Next, the CPU 36 causes the cooling fan 3
Environmental noise L1p at the above-mentioned places P1 to Pn during standby by rotating 5 (when the main body 1 is generating noise)
1, L1p2 ... L1pn are microphones 51 to 5n
, And output signals of the microphones 51 to 5n are captured and stored in the memory 38.

Next, the CPU 36 calculates the average value / L0 of the environmental noises L0p1, L0p2 ... L0pn stored in the memory 38 as /τ0=(L0p1+L0p2+...+L0
pn) / n and the average value of environmental noises L1p1, L1p2 ... L1pn stored in the memory 38 / L1
/L1=(L1p1+L1p2+...+L1pn)
/ N is calculated. / L0 is the environmental noise of the entire office when there is no copying machine of the sixth embodiment, and / L1 is the environmental noise of the entire office when there is noise generated from the copying machine of the sixth embodiment. Next, the CPU 36 compares the average values / L0 and / L1 and compares the difference (/ L1− / L).
0) is calculated, and the difference (/ L1− / L0) and the memory 37 are calculated.
In comparison with the standard value ΔL0 defined in
It is determined whether (L1− / L0) is smaller than the standard value ΔL0.

When (/ L1− / L0) is smaller than the standard value ΔL0, the CPU 36 determines that the noise generated by the main unit 1 does not significantly affect the environmental noise of the entire office, and the cooling fan 35 is turned on. Rotate as it is. Also,
When (/ L1- / L0) is not smaller than the standard value ΔL0, the CPU 36 determines that the noise generated by the main body 1 increases the environmental noise of the entire office, and reduces the noise generated by the main body 1. In order to reduce the environmental noise of the entire office, the cooling fan 35 is stopped to stop the heating of the fixing device 33.

There are a plurality of noise sources in the copying machine. In the seventh embodiment of the present invention, in the first embodiment, the cooling fan 35 and the polygon motor 25 serve as noise sources during standby. As shown in FIG. 12, a cooling fan 35
Generates noise S1 on the paper discharge side of the main body 1, and the polygon motor 2
5 causes noise S2 mainly on the back side of the main body 1 due to the mounting method. Further, the CPU 36 has a configuration shown in FIG. 13 instead of the process shown in FIG.
The processing shown in is performed.

The CPU 36 controls the cooling fan 35 during standby.
Also, the polygon motor 25 is once stopped to cause the microphone 2 to measure the environmental noise L0 while the main body 1 does not generate noise, and the output signal of the microphone 2 is captured and stored in the memory 38. Next, the CPU 36 rotates the cooling fan 35 and the polygon motor 25 to cause the microphone 2 to measure the environmental noise L1 at the place P in the standby state, captures the output signal of the microphone 2 and stores it in the memory 38. .

Next, the CPU 36 compares the environmental noises L0 and L1 stored in the memory 38 and compares them (L1-L0).
Is calculated, and this difference (L1-L0) is compared with a standard value ΔL0 defined in advance in the memory 37 (L1-L0).
0) is smaller than the standard value ΔL0. CP
When (L1-L0) is smaller than the standard value ΔL0, U36 determines that the noise generated in the seventh embodiment does not significantly affect the environmental noise at the location P, and the cooling fan 35 and The polygon motor 25 is rotated as it is.

If (L1−L0) is not smaller than the standard value ΔL0, the CPU 36 determines that the noise generated by the main body 1 has a great influence on the environmental noise at the place P, and the noise generated by the main body 1 is determined. In order to reduce the noise, first, the polygon motor 25 is stopped, and in this state, the environmental noise L1 ′ at the place P is measured by the microphone 2, and the output signal of the microphone 2 is captured and stored in the memory 38.

Next, the CPU 36 compares the environmental noises L0 and L1 'stored in the memory 38 and compares them (L1'-L).
0) is calculated, and the difference (L1′−L0) is compared with a standard value ΔL0 defined in advance in the memory 37 (L0).
1'-L0) is smaller than the standard value ΔL0. When (L1′−L0) is smaller than the standard value ΔL0, the CPU 36 determines that the noise generated by the main body 1 slightly affects the environmental noise at the location P, and stops the polygon motor 25. The cooling fan 35 is rotated as it is.

When (L1'-L0) is not smaller than the standard value .DELTA.L0, the CPU 36 determines that the noise generated by the main body 1 makes the place P noisy, and rotates the polygon motor 25 to cool it. The fan 35 is stopped.
Then, the CPU 36 in this state is the environmental noise L at the place P.
1 "is measured by the microphone 2 and the microphone 2
Of the output signal of the above and is stored in the memory 38.

Next, the CPU 36 compares the environmental noises L0 and L1 "stored in the memory 38 and compares the difference (L1" -L).
0) is calculated, and the difference (L1 ″ −L0) is compared with a standard value ΔL0 defined in advance in the memory 37 (L0).
1 "-L0) is smaller than the standard value ΔL0. If (L1" -L0) is smaller than the standard value ΔL0, the CPU 36 determines that the noise generated by the main body 1 is the environmental noise at the location P. It is determined that the influence on the fixing device 33 is reduced, and heating of the fixing roller of the fixing device 33 is stopped. Also, CPU
If (L1 ″ -L0) is not smaller than the standard value ΔL0, it is determined that the noise generated by the main body 1 has a large influence on the environmental noise at the location P, and the polygon motor 25 is stopped and fixed. The heating of the fixing roller of the device 33 is stopped.

In this way, when the environmental noise of the place P where the microphone 2 is located is increased due to the noise generated by the main body 1, while selecting the means that can preferentially reduce the environmental noise of the place P where the microphone 2 is located, Reduce environmental noise. Here, the reason why the polygon motor 25 is stopped before the cooling fan 35 is that it is shorter when the polygon motor 25 is set to a predetermined rotation speed than when the fixing device 33 is set to a predetermined copy-enabling temperature. This is because the rise time at the time of taking it becomes shorter.

By doing so, when there is a place where noise from the main body 1 causes noise, pay attention to the directivity of the noise and preferentially select and reduce each noise from the main body 1 accordingly. be able to. Therefore, the waiting time when making a copy can be minimized.

Since noise having a relatively high frequency (1 kHz or more) has little sound wave diffraction, the noise at a certain place can be reduced by the shielding plate. Therefore, in the eighth embodiment of the present invention, as shown in FIG.
As shown in FIG. 17, the shield plate 44 is attached to the left side portion of the main body 1 so as to be upside down. The noise source of the main body 1 is the cooling fan 35, and the noise S3 generated by the cooling fan 35 is the discharge port 4 through which the transfer paper from the fixing device 33 side to the discharge tray 7 passes.
Go out from 5 The microphone 2 is arranged at a predetermined place P on the front side of the main body 1, and measures the environmental noise at this place P. The shielding plate 44 is normally laid down on the side surface of the main body 1 and does not block the noise emitted from the paper discharge port 45 on the left side of the main body 1 to the outside. The shield plate 44 is driven by a drive unit to lie on the left side surface of the main body 1 or set so as to stand vertically on the left side surface of the main body 1.
Controlled by.

In the eighth embodiment, the CPU 36 has the configuration shown in FIG.
The process shown in FIG. 18 is performed instead of the process shown in FIG. CPU3
First, the reference numeral 6 first stops the cooling fan 35 during standby, causes the microphone 2 to measure the environmental noise L0 in a state where the main body 1 does not generate noise, and captures the output signal of the microphone 2 and stores it in the memory 38.

Next, the CPU 36 rotates the cooling fan 35 to cause the microphone 2 to measure the environmental noise L1 at the place P during standby (when the main body 1 is making noise), and the microphone 2 is measured. Of the output signal of the above and is stored in the memory 38. Next, the CPU 36 causes the memory 3
The environmental noises L0 and L1 stored in 8 are compared and the difference (L
1-L0) is calculated, and the difference (L1-L0) and the memory 3
It is determined whether (L1-L0) is smaller than the standard value ΔL0 by comparing with a standard value ΔL0 defined in advance in 7.

In the CPU 36, (L1-L0) is the standard value Δ
If it is smaller than L0, the noise generated by the main body 1 is at the above-mentioned location P.
The cooling fan 35 is rotated as it is because it is determined that the environmental noise in the above is not so affected. Also, C
When (L1-L0) is not smaller than the standard value ΔL0, the PU 36 determines that the generated noise of the main body 1 makes the environmental noise at the place P large (the place P is noisy), The shield plate 44 is set upright on the left side surface of the main body 1.

Next, the CPU 36 causes the microphone 2 to measure the environmental noise L1 'at the place P in this state, captures the output signal of the microphone 2 and stores it in the memory 38. Next, the CPU 36 compares the environmental noises L0 and L1 ′ stored in the memory 38, calculates a difference (L1′−L0) between them, and the difference (L1′−L0) and a predetermined value in the memory 37. Compared with the standard value ΔL0 that is present (L1′-L
0) is smaller than the standard value ΔL0. CP
When (L1′−L0) is smaller than the standard value ΔL0, U36 determines that the influence of the noise generated by the main body 1 on the environmental noise at the location P is acceptable, and the cooling fan 3
Rotate 5 as it is. Further, the CPU 36 uses (L
1′-L0) is not smaller than the standard value ΔL0, it is determined that the noise generated by the main body 1 is still making the place P noisy, and the cooling fan 35 is stopped to stop the heating of the fixing device 33. .

In each of the above embodiments, the specified value may be predetermined, or the office worker may be allowed to freely set it. Further, the environmental noise measured by the microphone 2 may be filtered by the A characteristic or the like. Also, noise reduction control was performed during standby,
Noise reduction control may be similarly performed during copying. Furthermore, the present invention can be similarly implemented in image forming apparatuses other than copying machines.

[0080]

As described above, according to the first aspect of the present invention, the noise measuring means for measuring the noise at a predetermined place apart from the main body and the noise measuring means for determining the predetermined noise when the main body does not generate noise. Of the first environmental noise measured at the location and the second environmental noise measured at the predetermined location by the noise measuring means when the main body is producing noise, and the comparison result is the specified value or more. And a noise reducing means for reducing the second environmental noise when it is, it is possible to reliably judge how much the noise generated by the image forming apparatus affects a predetermined place, and only when the influence is large, the image is displayed. It is possible to reduce the noise generated by the forming apparatus, and it is not necessary to suppress the image forming operation of the image forming apparatus more than necessary to reduce the noise. Moreover, the region where the noise is desired to be reduced by the output of the sound wave does not become loud on the contrary. Therefore, the generated noise can be effectively reduced, and the complexity and cost of the device can be suppressed.

According to the second aspect of the present invention, the noise measuring means for measuring the noise at the predetermined location apart from the main body and the noise measuring means for measuring the noise at the predetermined location when the main body does not generate noise. The first environmental noise is compared with the second environmental noise measured by the noise measuring means at a predetermined place during standby, and when the comparison result is equal to or more than a predetermined value, the second environmental noise is waited. This comparison is made by comparing the second environmental noise that has been reduced at the time of standby during image formation with the third environmental noise and the third environmental noise measured at a predetermined place by the noise measuring means during image formation of the main body. When the third environmental noise is reduced when the result is equal to or more than a prescribed value set in advance, and the comparison result of the first environmental noise and the second environmental noise is equal to or less than the prescribed value set in advance Stands by when the image is formed on the main unit Noise that reduces the third environmental noise when the environmental noise of 2 and the third environmental noise measured at a predetermined place by the noise measuring means are compared and the comparison result is equal to or more than a predetermined prescribed value. Since the reduction means is provided, it is possible to reliably judge how much the noise generated during standby of the image forming apparatus and the noise generated during image formation affect a predetermined place, and only when the influence is large, the image forming apparatus It is possible to reduce the noise generated at each time of standby and image formation. Moreover, the region where the noise is desired to be reduced by the output of the sound wave does not become loud on the contrary. For this reason,
The generated noise can be effectively reduced, and the complexity and cost of the device can be suppressed.

According to the third aspect of the present invention, a plurality of noise measuring means for measuring environmental noise at a plurality of places apart from the main body and a plurality of noise measuring means when the main body does not generate noise are provided. The average value of the first environmental noise measured at each location and the average value of the second environmental noise measured at each of the multiple locations by the plurality of noise measuring means when the main body is producing noise. And the average value is compared and the noise reduction means for reducing the noise generated by the main body when the comparison result is equal to or greater than the specified value is provided. The noise generated by the image forming apparatus can be reduced only when the influence is great. Moreover, the region where the noise is desired to be reduced by the output of the sound wave does not become loud on the contrary. Therefore, the generated noise can be effectively reduced, and the complexity and cost of the device can be suppressed.

[Brief description of drawings]

FIG. 1 is a block diagram showing a circuit configuration of a first exemplary embodiment of the present invention.

FIG. 2 is a sectional view showing a main body of the first embodiment.

FIG. 3 is a perspective view showing an appearance of the first embodiment.

FIG. 4 is a perspective view showing a part of the first embodiment.

FIG. 5 is a flowchart showing a processing flow of a CPU in the first embodiment.

FIG. 6 is a block diagram showing a circuit configuration of a second exemplary embodiment of the present invention.

FIG. 7 is a flowchart showing a processing flow of a CPU in the third embodiment of the present invention.

FIG. 8 is a flowchart showing a processing flow of a CPU in the fourth embodiment of the present invention.

FIG. 9 is a perspective view showing a fifth embodiment of the present invention.

FIG. 10 is a flowchart showing a processing flow of a CPU in the fifth embodiment.

FIG. 11 is a flowchart showing a processing flow of a CPU in the sixth embodiment of the present invention.

FIG. 12 is a plan view showing a seventh embodiment of the present invention.

FIG. 13 is a flowchart showing a processing flow of a CPU in the seventh embodiment.

FIG. 14 is a schematic view showing a part of an eighth embodiment of the present invention.

FIG. 15 is a side view showing a left side surface of the eighth embodiment.

FIG. 16 is a schematic view showing a part of the eighth embodiment.

FIG. 17 is a schematic view showing a part of the eighth embodiment.

FIG. 18 is a flowchart showing the processing flow of the CPU in the eighth embodiment.

[Explanation of symbols]

 1 Main Body 2 Microphone 25 Polygon Motor 35 Cooling Fan 36 CPU 44 Shielding Plate

Claims (3)

[Claims] 1. An image forming apparatus having a main body for generating an image by generating noise, wherein noise measuring means for measuring noise at a predetermined place apart from the main body, and the main body does not generate noise. Sometimes a first environmental noise measured at the predetermined place by the noise measuring means, and a second environmental noise measured at the predetermined place by the noise measuring means when the main body is producing noise. And a noise reducing unit that reduces the second environmental noise when the comparison result is equal to or more than a specified value. 2. An image forming apparatus having a main body that forms an image and generates different noises during standby and during image formation, and noise measuring means for measuring noise at a predetermined location distant from the main body. A first environmental noise measured at the predetermined location by the noise measuring means when the main body does not generate noise, and a second environmental noise measured at the predetermined location by the noise measuring means during standby. If the comparison result is greater than or equal to a predetermined specified value, the second environmental noise is reduced during standby and the second environmental noise reduced during standby during image formation, and the main body. When the image is formed, the third environmental noise measured by the noise measuring means at the predetermined place is compared, and if the comparison result is equal to or more than a predetermined value, the third environmental noise is Reduce the above When the comparison result of the environmental noise of No. 1 and the second environmental noise is less than or equal to a specified value that is specified in advance, the second environmental noise at the time of standby during the image formation of the main body and the noise measuring unit And a noise reducing means for comparing the third environmental noise measured at a predetermined place and reducing the third environmental noise when the result of the comparison is equal to or more than a prescribed value which is prescribed in advance. A characteristic image forming apparatus. 3. An image forming apparatus having a main body which forms an image and generates different noises during standby and during image formation, wherein a plurality of noise measurements are performed to measure environmental noise at a plurality of locations apart from the main body. Means, an average value of the first environmental noises respectively measured by the plurality of noise measuring means at the plurality of places when the main body is not generating noise, and when the main body is generating noise A second measured at each of the plurality of locations by the plurality of noise measuring means;
And an average value of the environmental noise of the above, and compares these average values, and when the comparison result is a specified value or more, a noise reducing unit for reducing the noise generated by the main body is provided. apparatus.