JP2009205115A - Fan control device and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fan control device, capable of reporting a state of a fan in detail based on the past state of the fan stored in time series, and an image forming apparatus using the fan control device. <P>SOLUTION: A plurality of values R obtained by dividing the rotating speed of the fan by a drive signal (voltage or duty ratio) input to the fan is stored as logs in time series. When R is out of an allowable range (Rmin-Rmax) (S3: Y or S6: Y), or when a state in which R is higher than a target value (R1-Rh) within the allowable range is continued for a fixed period or more (S13: Y), service error is determined. When a state in which R is lower than the target value within the allowable range is continued for a fixed period (S23: Y), disturbance of rotation of the fan by inclusion of foreign matter such as dust is determined, and an error display is performed to urge cleaning of the fan. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a fan control device that controls a fan, and more particularly, to a fan control device provided with means for notifying the state of the fan, and an image forming apparatus using the fan control device.

Conventionally, in various apparatuses such as an image forming apparatus, cooling with a fan has been considered. In addition, this type of fan changes its state due to changes over time. Thus, for example, when the current consumption of the fan increases due to changes over time, it has been proposed to reduce the number of resistance elements connected in series with the fan to suppress the decrease in the rotational speed (see, for example, Patent Document 1).
JP 2006-280162 A

  However, in the above-mentioned patent document, if the current consumption of the fan is large at that time, the number of the resistance elements is reduced, and the control classified in detail based on the past state of the fan stored in time series. Can not do. Therefore, the present invention provides a fan control device capable of notifying the fan state in detail based on the past state of the fan stored in time series, and image formation using the fan control device. It was made for the purpose of providing equipment.

  The fan control device of the present invention made to achieve the above object includes a fan driving means for inputting a drive command to the fan, a rotation speed detecting means for detecting the rotation speed of the fan, and a drive input by the fan driving means. A storage means for storing a plurality of parameters representing a correspondence relationship between the command and the rotation speed detected by the rotation speed detection means in a time series, and a state of the fan based on the plurality of parameters stored in the storage means. And a notification means for notifying.

  In the fan control device of the present invention configured as described above, the fan drive means drives the fan by inputting a drive command to the fan. The storage means stores a plurality of parameters indicating the correspondence relationship between the drive command input by the fan drive means and the rotation speed detected by the rotation speed detection means in time series, and the plurality of parameters stored in the storage means are stored in the storage means. Based on the parameters, the notification means notifies the fan status. For this reason, the notification means of this invention can notify in detail the state of a fan based on the said parameter memorize | stored in time series.

  Although the present invention is not limited to the following configuration, the values of the parameters stored by the storage means are continuously within a predetermined range of the target range within a permissible range, and the rotation speed is high. The notification means may notify an error corresponding to the state. In this case, it is possible to determine an error in the circuit or the like and perform an error notification corresponding to it.

  In addition, when the value of the plurality of parameters stored by the storage means deviates from the target range within the allowable range within the permissible range to the low speed side, the notification means returns an error corresponding to the state. May be announced. In this case, it can be determined that a foreign substance such as dust is mixed, and an error notification corresponding to the determination can be made.

  In addition, when the value of the parameter stored by the storage unit changes beyond a predetermined amount to the lower side of the rotation speed than the parameter value stored in the past, the notification unit is in that state. The corresponding error may be announced. In this case, it can be determined that the rotation of the fan has been hindered by an abnormality other than dust, and an error notification corresponding to the fan rotation can be made. Note that the value of the parameter stored in the past may be a value stored last time, a past average value, or other values.

  Furthermore, in any one of the above fan control devices, various parameters can be applied as the parameters. For example, the rotation speed detection unit detects the parameter based on the voltage applied by the fan drive unit to the fan as the drive command or the duty ratio of the PWM signal input to the fan by the fan drive unit as the drive command. It may be a value obtained by dividing the number of rotations.

  Further, an image forming apparatus according to the present invention uses any one of the fan control devices described above. In the image forming apparatus of the present invention configured as described above, the state of the fan for cooling the inside or the like can be notified in detail as described above.

  Next, embodiments of the present invention will be described with reference to the drawings. As described below, the present embodiment applies the present invention to a so-called laser printer as an example of an image forming apparatus.

1. FIG. 1 is a perspective view showing the appearance of a laser printer 1 according to the present embodiment. The laser printer 1 is installed with the upper side of the paper as the upper side in the direction of gravity, and usually the left front side of the paper is the front side. Used as.

  The housing 3 of the laser printer 1 is formed in a substantially box shape (a rectangular parallelepiped shape), and a recording medium discharged from the housing 3 after printing is placed on the upper surface side of the housing 3. A paper discharge tray 5 is provided. In the present embodiment, paper such as paper or an OHP sheet is assumed as the recording medium.

  Further, the paper discharge tray 5 is configured with an inclined surface 5a that is inclined so as to descend from the upper surface of the housing 3 toward the rear side, and printing is finished on the rear end side of the inclined surface 5a. A discharge unit 7 for discharging the recording medium is provided.

  The upper cover 9 formed in a substantially U-shape so as to surround the paper discharge tray 5 (inclined surface 5a) in the casing 3 includes a case where the laser printer 1 is connected to the network and a case where the laser printer 1 is disconnected from the network. A line switch 1a for switching between, a job cancel switch 1b for forcibly ending (interrupting) printing, a display panel 1c as an example of notification means for displaying various information, and the like.

  The laser printer 1 is provided with a paper feed cassette 11 detachably below the housing 3, and an image is recorded on a recording medium housed in the paper feed cassette 11 by electrophotography in the housing 3. A known printer engine (not shown) for forming (printing) and discharging from the discharge unit 7 is provided. In addition, fans 41 and 42 for cooling the printer engine, the power supply unit, and the like housed therein are provided on the side surface of the housing 3.

2. Next, the configuration of the drive system of the fans 41 and 42 as an example of the fan control device will be described. Since the drive systems of the fans 41 and 42 have substantially the same configuration, the drive system of the fan 41 will be described in the following description.

  FIG. 2 is a circuit diagram illustrating the configuration of the drive system of the fan 41. As shown in FIG. 2, the fan 41 (FAN) is controlled by an ASIC (application specific integrated circuit) 50 including a CPU 51, a ROM 52, and a RAM 53. An FG (Freqency Generator) signal is input from the fan 41 to the FGIN terminal as an example of the rotational speed detection means of the ASIC 50. The display panel 1c is also connected to the ASIC 50. Further, the ASIC 50 includes a FAN_H terminal for driving the fan 41 at a high speed, a FAN_M terminal for driving the fan 41 at a medium speed, and a FAN_L terminal for driving the fan 41 at a low speed. The driving voltage is supplied to the input terminal FAN_IN of the fan 41 via 60. That is, the FAN_H terminal, the FAN_L terminal, the FAN_M terminal, and the driving circuit 60 correspond to the fan driving unit.

  Next, the configuration of the drive circuit 60 will be described in detail. As shown in FIG. 2, the FAN_H terminal is connected via a resistor R2 to the base of a transistor Tr1 whose base and emitter are connected via a resistor R1. The emitter of the transistor Tr1 is grounded, and the collector is connected via a resistor R4 to the base of the transistor Tr2 whose base and emitter are connected via a resistor R3. The emitter of the transistor Tr2 is connected to a 24V DC power supply, and the collector is connected to the input terminal FAN_IN of the fan 41. Therefore, when an “H” level signal is output from the FAN_H terminal, a DC voltage of approximately 24 V is supplied to the input terminal FAN_IN, and the fan 41 can be driven at high speed.

  The FAN_M terminal is connected via a resistor R7 to the base of a transistor Tr3 whose base and emitter are connected via a resistor R6. The emitter of the transistor Tr3 is grounded, and the collector is connected via a resistor R9 to the base of the transistor Tr4 whose base and emitter are connected via a resistor R8. The emitter of the transistor Tr4 is connected to a 24V DC power supply via a Zener diode D1, and the collector is connected to the input terminal FAN_IN of the fan 41. Therefore, when an “H” level signal is output from the FAN_M terminal, a DC voltage obtained by subtracting the voltage drop due to the Zener diode D1 from 24V is supplied to the input terminal FAN_IN, so that the fan 41 can be driven at medium speed. it can.

  The FAN_L terminal is connected via a resistor R12 to the base of a transistor Tr5 whose base and emitter are connected via a resistor R11. The emitter of this transistor Tr5 is grounded, and its collector is connected via a resistor R14 to the base of a transistor Tr6 whose base and emitter are connected via a resistor R13. The emitter of the transistor Tr12 is connected to a 24V DC power supply via the Zener diodes D2 and D3, and the collector is connected to the input terminal FAN_IN of the fan 41. For this reason, when an “H” level signal is output from the FAN_L terminal, a DC voltage obtained by subtracting the voltage drop due to the Zener diodes D2 and D3 from 24V is supplied to the input terminal FAN_IN to drive the fan 41 at a low speed. Can do. Further, there may be further steps such as ultra-low speed driving (three Zener diodes connected in series).

  In FIG. 2, the case where an analog DC voltage is supplied to the input terminal FAN_IN of the fan 41 has been described as an example. However, when the PWM signal can be input to the input terminal FAN_IN of the fan 41 and driven, Can also be configured as follows. That is, in this case, as shown in FIG. 3, a CTL signal as a PWM signal is directly input from the FAN_CTL signal terminal of the ASIC 50 to the input terminal FAN_IN of the fan 41, and the fan 41 is driven at a speed corresponding to the duty ratio of the CTL signal. Can be driven.

3. Fan Control Processing In any case, as shown in FIG. 4, the larger the voltage input to the fan 41 or the greater the duty ratio (PWM DUTY) of the CTL signal input to the FAN 41, the larger the fan 41 The number of rotations increases. The rotational speed of the fan 41 increases substantially in proportion to the voltage or duty ratio until the rotational speed reaches a certain value, and does not further increase when the rotational speed reaches a certain value.

  Therefore, in the present embodiment, the rotation speed is divided by the voltage or duty ratio as a parameter representing the correspondence between the drive command (the voltage or duty ratio) input to the fan 41 and the rotation speed of the fan 41. The value R is adopted and the following control is executed. FIG. 5 is a flowchart showing a control process for the fan 41. This process is started when the laser printer 1 is turned on, and the same control is performed on the fan 42 in parallel. Further, a plurality of the parameters R are stored in a time series as a log in the RAM 53 as an example of a storage unit during execution of this processing.

  As shown in FIG. 5, in this process, the fan 41 is first rotationally driven in S1 (S represents a step: the same applies hereinafter). In subsequent S2, counters Nh and Nl described later are reset to zero. Further in S3, it is determined whether or not R exceeds the allowable maximum value Rmax. If it exceeds (S3: Y), in S4, “Fan error” “Call a service person” or the like. An error message is displayed on the display panel 1c, and the process proceeds to S5. In S5, the apparatus (that is, the entire laser printer 1 including the fan 41) is stopped, and the process is temporarily terminated. On the other hand, if R ≦ Rmax (S3: N), the process proceeds to S6, and it is determined whether or not R is below the allowable minimum value Rmin. If R <Rmin (S6: Y), the process proceeds to S4 described above, and if R ≧ Rmin (S6: N), the process proceeds to S10.

  In S10, it is determined whether or not R exceeds the upper limit value Rh of the target value as an example when the target range is out of the allowable range and the rotational speed is higher. If R ≦ Rh (S10: N), after the counter Nh is reset to 0 in S11, the process proceeds to S20 described later. On the other hand, if R> Rh (S10: Y), after the counter Nh is incremented by 1 in S12, it is determined whether or not the counter Nh exceeds 100 in S13. S13: N), the process proceeds to S20. That is, the counter Nh is a counter that counts the number of times that R has continuously exceeded the target upper limit value Rh within an allowable range (Rmin ≦ R ≦ Rmax). If the counter Nh exceeds 100 (S13: Y), an error message such as “Fan error” or “Call a serviceman” is displayed on the display panel 1c in S14, and the processing is performed in S5 described above. Migrate to

  On the other hand, when the counter Nh does not exceed 100 (S13: N) or R does not exceed the upper limit value Rh of the target value (S10: N), R is the lower limit value of the target value in S20. It is determined whether or not it is below Rl (an example when the target range is within the allowable range and the rotational speed deviates to the low side). If R ≧ Rl (S20: N), after the counter Nl is reset to 0 in S21, the process proceeds to S30 described later. On the other hand, if R <Rl (S20: Y), after the counter Nl is incremented by 1 in S22, it is determined whether or not the counter Nl exceeds 100 in S23. That is, the counter Nl is a counter that counts the number of times that R has continuously exceeded the lower limit value Rl of the target value within the allowable range (Rmin ≦ R ≦ Rmax). If the counter Nl exceeds 100 (S23: Y), an error message such as “Fan error” “Please clean the fan” is displayed on the display panel 1c in S24, and the processing is as described above. The process proceeds to S5.

  If the counter Nl does not exceed 100 (S23: N), in S25, the difference d obtained by subtracting the previously acquired R from the currently acquired R is the allowable value (negative value) of the difference. ) It is determined whether or not it is below D. If the difference d is less than the permissible value D (S25: Y), an error message such as “Fan error” “Call a serviceman” is displayed on the display panel 1c in S26, and the processing is as described above. The process proceeds to S5. On the other hand, if D ≦ d (S25: N), it is determined in S27 whether or not the value obtained by doubling the currently acquired R is below the average value Rave of R acquired so far. The If 2R is below Rave (S27: Y), an error message such as “Fan error” or “Call a serviceman” is displayed on the display panel 1c in S28, and the process proceeds to S5 described above. To do.

  On the other hand, if 2R ≧ Rave (S27: N), the process proceeds to S30 as in the case of R ≧ Rl (S20: N). In S30, after waiting for one hour, the process proceeds to S3 described above.

  With the above processing, in the present embodiment, the state of the fan 41 can be notified in detail as follows based on the parameter R stored in time series. That is, as illustrated in FIG. 6, a target value defined by Rh and Rl and an allowable range defined by Rmax and Rmin are set for R. In FIG. 6, the vertical axis is “rotational speed / voltage”, but this corresponds to the drive system shown in FIG. 2, and when the drive system shown in FIG. It becomes the same figure as "rotational speed / duty ratio".

  If R is out of the allowable range (S3: Y or S6: Y), the ASIC 50 determines that an error has occurred, displays an error, and then stops the apparatus (S4, S5). In addition, when the state where R is within the allowable range and higher than the target value continues for a certain period or longer (S13: Y), the ASIC 50 determines that the drive circuit 61 that drives the fan 41 is defective and displays an error. The apparatus is stopped above (S14, S5).

  Furthermore, when the state where R is within the allowable range and lower than the target value continues for a certain period or longer (S23: Y), the ASIC 50 determines that the foreign matter such as dust is mixed and the rotation of the fan 41 is prevented, After displaying an error message prompting cleaning of the fan 41, the apparatus is stopped (S24, S5). Furthermore, when R is extremely reduced (S25: Y or S27: Y), the ASIC 50 determines that the rotation of the fan 41 has been hindered by an abnormality other than dust, displays an error, and stops the device. (S26, S28, S5). Thus, in the present embodiment, the state of the fan 41 can be notified in detail.

  In addition, this invention is not limited to the said embodiment at all, It can implement with a various form in the range which does not deviate from the summary of this invention. For example, in the above embodiment, when the rotation of the fan 41 is hindered by foreign matters such as dust (S23: Y), an error message such as “Fan error” “Please clean the fan” is displayed. Although the apparatus is stopped (S4, S5), the fan 41 may be automatically rotated at a high speed to remove dust and the like. In that case, the fan 41 is rotated at a high speed during a time when there are few people such as midnight, or when the same laser printer 1 is connected to the same network, the fan 41 is rotated at a high speed by communication between the laser printers 1. It is also possible to shift the time to be shifted. By doing so, it is possible to reduce the problem of noise accompanying the high-speed rotation of the fan 41.

  In the above embodiment, the same error message is displayed in S4, S14, S26, and S28. However, an error code corresponding to each error is also displayed and displayed according to each error cause. May be different. Furthermore, the present invention can be applied not only to an image forming apparatus other than a laser printer, but also to various apparatuses using a fan. Further, various parameters other than the above can be adopted as parameters.

1 is a perspective view illustrating an appearance of a laser printer to which the present invention is applied. It is a circuit diagram showing the structure of the drive system of the fan of the laser printer. It is a circuit diagram showing the structure of the other form which concerns on the drive system of the fan. It is explanatory drawing showing the relationship between the drive command in each said drive system, and rotation speed. It is a flowchart showing the control process with respect to the said fan. It is explanatory drawing showing the relationship of the various values in the control processing.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Laser printer 1c ... Display panel 41, 42 ... Fan 60 ... Drive circuit 50 ... ASIC 51 ... CPU
52 ... ROM 53 ... RAM

Claims (6)

Fan drive means for inputting a drive command to the fan;
A rotational speed detecting means for detecting the rotational speed of the fan;
Storage means for storing a plurality of parameters representing a correspondence relationship between the drive command input by the fan drive means and the rotation speed detected by the rotation speed detection means in time series;
Notification means for notifying the state of the fan based on the plurality of parameters stored in the storage means;
A fan control device comprising:   When the value of the plurality of parameters stored by the storage means deviates from the target range within the allowable range within the permissible range to the higher rotation speed, the notification means notifies an error corresponding to the state. The fan control device according to claim 1, wherein:   When the value of the plurality of parameters stored by the storage means deviates from the target range within a permissible range for a predetermined number of times to the low speed side, the notification means notifies an error corresponding to the state. The fan control device according to claim 1, wherein the fan control device is a fan control device.   When the value of the parameter stored by the storage means changes more than a predetermined amount to the lower side of the rotational speed than the parameter value stored in the past, the notification means corresponds to the state. The fan control device according to any one of claims 1 to 3, wherein an error is notified.   The parameter is the rotation detected by the rotation speed detection means based on the voltage applied by the fan drive means to the fan as the drive command or the duty ratio of the PWM signal input to the fan by the fan drive means as the drive command. The fan control device according to claim 1, wherein the fan control device is a value obtained by dividing the number.   An image forming apparatus using the fan control device according to claim 1.

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