JP2006126250A - Image recording device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To takes a measure against a temperature rise by rotating a fan even in standby mode while suppressing noise by using the fan which can reverse when the fan has larger temperature rise suppression effect when serving as an air discharge side, and making the fan operates as the discharge side in printing mode and as a suction side in the standby mode. <P>SOLUTION: An image recording device having a cooling fan motor whose blade rotating direction can be switched between normal rotation and reversing rotation and a printing state detecting means of detecting the printing state and standby state is characterized in that the rotating direction of the cooling fan motor is switched between the printing state and the standby state. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an image recording apparatus according to a cooling fan control method of an image forming apparatus using an electrophotographic process such as a copying machine or a laser printer.

Conventionally, in this type of image recording apparatus, a heater is provided to fix the toner. The influence of the heat generated by the heater, a power supply board and a control board having electronic components in the image recording apparatus, a cartridge, a mechanical part, etc. In order to suppress the temperature rise, a cooling fan is provided, for example, as in Patent Document 1, and the temperature inside the image recording apparatus is suppressed by rotating the cooling fan to form an air path.
Japanese Patent Laid-Open No. 06-202398

  However, when the fan is rotated, noise due to the wind noise of the wing caused by the rotation of the fan becomes a problem.

  In particular, the rotation in the direction in which hot air in the image recording apparatus is discharged outside the apparatus, that is, the noise when the fan is rotated in the discharge direction is increased.

  Therefore, rotation is set in the discharge direction when the temperature suppression effect is greater when the fan blades are rotated toward the discharge side than when the fan blades are rotated toward the suction side.

  In this case, there is no problem even if the fan is rotated in the discharge direction because the sound of transporting paper other than the fan and the driving sound of the motor, etc. is loud during printing, but when printing is stopped, that is, during standby There was a problem that the fan had to be stopped and the temperature rise could not be suppressed during standby.

  The present invention has been made paying attention to the above points, and when the fan wind direction has a greater effect of suppressing the temperature rise on the discharge side, the fan can be rotated in the forward and reverse directions to use the discharge side at the time of printing and suction at the time of standby. Accordingly, an object of the present invention is to provide an image recording apparatus that can take measures against temperature increase by rotating a fan while suppressing noise even during standby.

  In the image recording apparatus having the cooling fan motor capable of switching the rotation direction of the wing of the cooling fan motor between forward rotation and reverse rotation and the print state detection means for detecting the print state and the standby state, the print state and standby The rotation direction of the cooling fan motor is switched in the state, and control such as discharge direction rotation is performed in the print state, and suction direction rotation is performed in the standby state.

  Further, the direction of rotation is switched depending on the temperature inside the machine by means of the temperature inside the machine that detects the temperature inside the machine.

  By performing such control, it is possible to suppress a rise in temperature and to reduce noise by driving the fan even during standby.

  In an image recording apparatus having a cooling fan motor capable of switching the rotation direction of the wing of the cooling fan motor between forward rotation and reverse rotation and a print state detection means for detecting a print state and a standby state, cooling is performed in the print state and the standby state. Switch the direction of rotation of the fan motor.

  By performing such control, it is possible to suppress a rise in temperature and to reduce noise by driving the fan even during standby.

  Embodiments of the present invention will be described below with reference to the drawings.

  Hereinafter, description will be given based on the drawings.

  FIG. 1 is a schematic configuration diagram of an image forming apparatus using an electrophotographic process, and shows, for example, a laser beam printer.

  The laser beam printer main body 101 (hereinafter referred to as the main body 101) has a cassette 102 for storing the recording paper S, a cassette presence / absence sensor 103 for detecting the presence or absence of the recording paper S in the cassette 102, and the size of the recording paper S in the cassette 102. A cassette size sensor 104 (consisting of a plurality of microswitches) for detection, a paper feed roller 105 for feeding the recording paper S from the cassette 102, and the like are provided. A registration roller pair 106 that synchronously conveys the recording paper S is provided downstream of the paper supply roller 105. Further, an image forming unit 108 that forms a toner image on the recording paper S based on the laser beam from the laser scanner unit 107 is provided downstream of the registration roller pair 106. Further, a fixing device 109 that thermally fixes the toner image formed on the recording paper S is provided downstream of the image forming unit 108, and a top sensor 150 that detects the fed paper upstream of the fixing device 109. Downstream of the fixing device 109, a paper discharge sensor 110 that detects the conveyance state of the paper discharge unit, a paper discharge roller 111 that discharges the recording paper S, and a stacking tray 112 on which the recording paper S that has been recorded are stacked are provided. ing.

  Further, a door 151 that opens and closes in order to replace the toner is provided.

  The door 151 has a door open / close switch 152 connected to an open / close detection circuit, and can detect a door open / closed state.

  The laser scanner 107 emits a laser beam modulated based on an image signal (image signal VDO) transmitted from an external device 128 described later, and the laser beam from the laser unit 113 is described later. It comprises a polygon motor 114 for scanning on the photosensitive drum 117, an imaging lens 115, a folding mirror 116, and the like.

  The image forming apparatus 108 includes a photosensitive drum 117, a primary charging roller 119, a developing device 120, a transfer charging roller 121, a cleaner 122, and the like necessary for a known electrophotographic process. The fixing device 109 includes a fixing film 109a, a pressure roller 109b, a ceramic heater 109c having a heating element provided inside the fixing film, and a thermistor 109d for detecting the surface temperature of each heating element of the ceramic heater 109c. Yes.

  The main motor 123 applies a driving force to the paper feed roller 105 via a paper feed roller clutch 124, and a resist roller pair 106 via a resist roller 125, and further includes an image forming unit including a photosensitive drum 117. Driving force is also applied to each unit 108, the fixing device 109, and the paper discharge roller 111.

  Reference numeral 129 denotes a cooling fan motor capable of switching between forward and reverse rotation directions.

  Reference numeral 309 denotes an in-machine temperature sensor that detects the in-machine temperature, and detects the in-machine temperature.

  An engine controller 126 controls the electrophotographic process by the laser scanner unit 107, the image forming unit 108, and the fixing unit 109, controls the conveyance of the recording paper in the main body 101, and controls the rotation of the cooling fan motor 129. .

  A CPU 135 for performing control is provided in 126, and performs drive control of the cooling fan motor 129 and general control of the LBP main body.

  Reference numeral 127 denotes a video controller, which is connected to an external device 131 such as a personal computer via a general-purpose interface (Centronics, RS232C, etc.) 130, and develops image information sent from this general-purpose interface into bit data. The bit data is sent to the engine controller 126 as a VDO signal.

  FIG. 2 shows a control circuit for the cooling fan 129 and the in-machine temperature sensor 309 according to the present invention.

  In this circuit diagram, from the CPU 135 through the resistor 501 to the base of the transistor 502, the emitter is GND, the collector is through the resistor 503 to Vcc, the collector of the transistor 502 is to the base of the transistor 504, the base of 504 is to Vcc, the collector Is connected to a cooling fan 129.

  The fan can be driven by switching the signal of the CPU 135 between H and L.

  The CPU 135 is connected to the cooling fan 129 via the resistor 505. When the cooling fan 129 is locked, a predetermined signal is sent to the CPU 135.

  Further, the CPU 135 is connected to the cooling fan 129 via a resistor 505, and the rotation direction of the cooling fan 129 can be switched between forward rotation and reverse rotation.

  One of the in-machine temperature sensor 309 is connected to GND, the other is connected to Vt through a resistor 507, and connected to the CPU 135 through a resistor 508, and detects the temperature in the machine.

  The CPU 135 includes a ROM 135a and a comparator 135b, and can compare a preset set temperature T1 and a detected temperature Tt.

  Now, the present embodiment will be described based on a flowchart.

  FIG. 3 shows a flowchart of this embodiment.

  First, it is determined whether a print signal has been sent (step S1). If printing is in progress, the SWCH signal is set to H level, that is, the discharge direction (S2), and the FON signal is set to H level (S3). Drive. Next, it is determined whether or not printing is stopped (S4). If printing is stopped, the FON signal is set to L level (S5), and the process proceeds to S6. If the print signal is not sent in S1, the SWCH signal is set to L level, that is, the suction direction (S6), the FON signal is set to H level (S7), and the fan 129 is driven. Next, it is determined whether a print signal has been sent (S8). If a print has been sent, the FON signal is set to L level (S9), and the process proceeds to S2.

  By performing such control, the fan can be rotated in the discharge direction during printing, and the fan can be rotated in the suction direction when printing is stopped, that is, during standby.

  Although the overall configuration of the present embodiment is almost the same as that of the first embodiment, the rotation direction is switched between printing and standby in the first embodiment, whereas in the present embodiment, the temperature in the apparatus is detected and the temperature is changed. The direction of rotation is switched.

  Example 2 will be described based on a flowchart.

  FIG. 4 shows a flowchart of this embodiment.

  First, it is determined whether or not a print signal has been sent (step S11). If a print signal has been sent, it is determined whether or not the detected temperature Tt is lower than a predetermined set value T1 (S12). If it is higher, the SWCH signal is set to the H level, that is, the discharge direction (S21), the FON signal is set to the H level (S22), and the fan 129 is driven. Next, it is determined whether or not printing is stopped (S23). If printing is stopped, it is determined whether or not the detected temperature Tt is lower than a predetermined set value T1 (S24). The signal is set to L level (S25), the fan is stopped, and the SWCH signal is set to L level, that is, the suction direction (S26), and the process proceeds to S19.

  If the temperature is lower than T1 in step S12, the SWCH signal is set to L level, that is, the suction direction (S13), the FON signal is set to H level (S14), and the fan 129 is driven. Next, it is determined whether or not printing is stopped (S15). If printing is stopped, it is determined whether or not the detected temperature Tt is higher than a predetermined set value T1 (S16). The signal is set to the L level (S17), the fan is stopped, the SWCH signal is set to the H level, that is, the discharge direction (S18), and it is determined whether or not the printing is stopped (S20).

  If there is no print instruction in S11, the SWCH signal is set to L level, that is, the suction direction (S27), the FON signal is set to H level (S28), and the fan 129 is driven. Next, it is determined whether a print signal has been sent (S29). If a print has been sent, the process proceeds to S12.

  By performing such control, the fan is rotated in the discharge direction when printing and the internal temperature is high, and the fan is rotated in the suction direction when the internal temperature is low. Can be made as small as possible.

Schematic diagram of an image recording apparatus according to the present invention The figure which shows the control circuit of the fan motor in invention The flowchart which shows this invention Example 1. The flowchart which shows this invention Example 2.

Explanation of symbols

101 Image forming apparatus 109 Thermal fixing device 129 Cooling fan 135 CPU
309 In-flight detection sensor

Claims (2)

  In an image recording apparatus having a cooling fan motor capable of switching the rotation direction of the wing of the cooling fan motor between forward rotation and reverse rotation and a print state detection means for detecting a print state and a standby state, cooling is performed in the print state and the standby state. An image recording apparatus characterized by switching a rotation direction of a fan motor.   2. The image recording apparatus according to claim 1, further comprising an in-machine temperature detecting means for detecting an in-machine temperature, and switching a rotation direction according to the detected temperature.

Images